Entitled load detection sensor and the load detection sensor unit

Technical field

[0001]

　The present invention is, inside the vehicle seat, below the vehicle seat, or about the load sensor and the load detection sensor unit is provided, between the cover covering the vehicle seat and the vehicle seat.

Background technique

[0002]

　One of the safety system in a vehicle, the alarm system to warn the seat belt is not worn while riding has been put into practical use. This alarm system, when the wearing of the seat belt is not detected in the state in which the seating of a person is detected, a warning is issued. As the load detection sensor used like in such alarm systems have been proposed Patent Document 1.

[0003]

　The load sensor of Patent Document 1 includes a plurality of spaced one electrode connected with the film surface secured to and electrically single line of the first film, opposite the first film surface in the second film a plurality of spaced apart other electrode is secured to the film surface and are connected in an electrically single line that is disposed between the first film and the second film as between the electrodes is spaced apart opposed It was and a spacer.

[0004]

Patent Document 1: Laid-Open Publication No. 9-315199

Summary of the Invention

[0005]

　However, the load detection sensor of Patent Document 1, the switch is a multiple composed of the one electrode and the other electrode, there is a case where the switches are connected in series. In such cases, one of a pair of terminals in the load detection sensor disposed on the first film, it is required to place the other to the second film.

[0006]

　Thus the load detection sensor of Patent Document 1, for example, for the case of connecting a resistor to be parallel with the switch, it is necessary to provide a resistance to the outside of the first film and the second film, to provide the resistance there is a tendency to increase the size of an increase in the number of parts.

[0007]

　The present invention aims to provide a load sensor capable of placing a pair of terminals to one of the pair of sheets.

[0008]

　Load detection sensor of the present invention for solving the above problems, at least one or more of the first electrode, and a first electrode sheet having a first contact portion, the second electrode being opposed to the first electrode, a second electrode sheet having a second contact portion which is opposed to the first contact portion connected to the second electrode is disposed between the first electrode sheet and the second electrode sheet, at least the a spacer having an opening and between the first electrode and the first contact portion and the second contact portion and between the second electrode, and one terminal electrically connected to the first electrode, the first and a second terminal electrically connected to the first contact portion, said switch between the first electrode and the second electrode is configured, if the external pressure is not applied between the first contact portion and second contact portion electrical connection connection maintenance portion is maintained is also configured to, before Series number of the switch that one terminal to be electrically connected to in series between the other terminal, characterized in that it is an odd number.

[0009]

　In such a load sensor, formed on the circuit portion formed on the first electrode sheet through a first contact portion of the first electrode sheet and a second contact portion of the second electrode sheet and the second electrode sheet It is always in continuity state and the circuit portion. Therefore, as long as the series number of switches connected in series in the circuit in the load detecting sensor is odd, it is possible to arrange the pair of terminals of the circuit to the first electrode sheet in the load detecting sensor. Thus, the load sensor capable of placing a pair of terminals to the first electrode sheet is provided.

[0010]

　Also, a portion including the second contact portion in the second electrode sheet is preferably a plate spring that presses the second contact portion to the first contact portion.

[0011]

　In such a case, it is possible to maintain the state in which even without other member and the first contact portion and second contact portion is always connected, it is possible to prevent a connection failure.

[0012]

　Further, the second electrode sheet is preferably made of a metal sheet.

[0013]

　In such a case, the second electrode sheet is a metal, for thermal effects is small, whether used load sensor in a high temperature environment reduction and a low-temperature environment, the sensitivity of the load sensor is stabilized. Moreover, since a metal, it is possible to reduce the damage, it is possible to improve the durability.

[0014]

　Moreover, against the said first electrode sheet and the second electrode sheet, preferably further comprises a pressing member for maintaining a state in which the a first contact portion and second contact portion are in contact.

[0015]

　In such a case, it is possible to increase the pressing force of the second contact portion with respect to the first contact portion. Thus, for example, sites pressing the second contact unit against the first contact portion due to vibration of the vehicle seat is displaced, that the first contact portion and second contact portion can be reduced to be a non-connected state it can.

[0016]

　The first electrode covering at least the second contact portion of the first contact portion and the second electrode sheet in the sheet, covering member for fixing the state of the a first contact portion and second contact portion are in contact preferably further comprising a.

[0017]

　In such a case, such as site-pressing of the second contact portion with respect to the first contact portion due to vibration of the vehicle seat is displaced, that the first contact portion and second contact portion is disconnected it can be reduced.

[0018]

　The first electrode sheet includes a first sheet through hole penetrating to the other surface opposite to the one face from one face to be opposed to the second electrode sheet, the first electrode , the through the first conductive member provided on the first sheet through hole, said to be the other connecting circuits sites and electrically arranged in face preferred.

[0019]

　In such a case, it is possible to retrieve the one terminal to the other surface of the first electrode sheet, a simplified when connecting to another electronic component. Moreover, since it is possible to provide a circuit portion on the other side, it is not necessary on one face providing the circuit portion, it is possible to reduce the unevenness by the circuit portion of one surface. Thus, it is possible to stabilize the sensitivity of the load sensor.

[0020]

　The first of the one surface side of the sheet through hole opening, the is positioned in the region where the first electrode is arranged on one surface, the first sheet through hole provided in the first electrode through are electrodes through hole preferably has an air hole that communicates with the opening between the first electrode and the second electrode.

[0021]

　In such a case, the sheet through holes, a first electrode disposed on one surface of the first electrode sheet, connected to the circuit portion electrically connected to the other surface side of the first electrode sheet not use holes only, so that also serves as an exhaust hole for discharging air of the spacer to the outside. Therefore, it is possible to improve the durability of the first electrode sheet in comparison with the case where the the connecting hole and the exhaust hole separately. Moreover, it is not necessary to provide the exhaust holes separately, it is possible to save space.

[0022]

　The first electrode sheet, a position different from the first sheet through hole, the penetrating from one surface to be opposed to the second electrode sheet to the opposite other surface and one surface has a second sheet through hole, wherein the first contact portion, said through second conductive member provided in the second sheet through hole, said to be the other surface to the circuit portion electrically connected to be arranged It is preferred.

[0023]

　In such a case, the other surface of the first electrode sheet can be taken out of the pair of terminals, a simplified when connecting to another electronic component. Moreover, since it is possible to provide a circuit portion on the other side, it is not necessary on one face providing the circuit portion, it is possible to reduce the unevenness by the circuit portion of one surface. Thus, it is possible to stabilize the sensitivity of the load sensor.

[0024]

　Moreover, the disposed on the other surface preferably has an electrically connects resistor and said first electrode and said first contact portion.

[0025]

　In such a case, even if the thickness of the resistance is large, it is possible to prevent the sensitivity of the load sensor by the thickness deteriorates.

[0026]

　Moreover, the disposed on one surface, preferably has a printed resistor connecting said first electrode and said first contact portion electrically.

[0027]

　If this is done, it thin as compared with the case of arranging the chip resistor. The printing resistance, because it is housed inside covered with a first insulating sheet and the spacer, the influence of static electricity as compared with the case of arranging a resistance on the outer surface of the first insulating sheet is reduced.

[0028]

　Moreover, the the load detection sensor according to any, disposed on the switch, may be a load detecting sensor unit and a switch pressing portion for pressing the switch when the external pressure is applied.

[0029]

　Further, the load sensing sensor unit comprises a housing having an accommodation space for accommodating the load detection sensor, and a housing cover for covering the accommodating space, the switch pressing unit, to ensure that is provided in the housing cover It can also be.

[0030]

　In such a load detecting sensor unit, since the switch pressing portion disposed on the load detection sensor switch presses the switch, it can be transmitted properly load via the switch pressing portion to the load sensor.

[0031]

　According to the present invention as described above, the load sensor and the load detection sensor unit capable of placing a pair of terminals to one of the pair of sheets is achieved.

BRIEF DESCRIPTION OF THE DRAWINGS

[0032]

FIG. 1 is an exploded view showing the construction of a load detection sensor unit.
Is an exploded view showing the FIG. 2 of the load sensor configuration.
3 is a diagram showing a cross-section of the load sensor.
4 is a diagram showing an equivalent circuit of the load detection sensor.
FIG. 5 is an exploded view showing the construction of a load detection sensor in the second embodiment.
6 is a diagram showing a cross section of line Z-Z in FIG.
7 is a diagram showing an equivalent circuit of the load sensor in the second embodiment.
8 is a diagram showing a state of a cross section of the load sensor according to another embodiment.

DESCRIPTION OF THE INVENTION

[0033]

(1) First Embodiment
　will be described in detail with reference to the drawings for the first embodiment for carrying out the present invention. Figure 1 is an exploded view showing the structure of a load detection sensor unit. As shown in FIG. 1, the load sensor unit 1 includes the base 2, the housing 3, the housing cover 4 and the load detection sensor 5 as main components.

[0034]

　Base 2 has a mounting portion 21 that the housing 3 is placed, and a pair of hook portions 22 connected to the mounting portion 21. The mounting portion 21 has a plurality of through holes 23 which penetrates over to the surface of the opposite side is formed with its mounting surface from the mounting surface to be mounted to housing 3.

[0035]

　A pair of hook portions 22 are opposite sides of the mounting portion 21 are fitted to the two spring portions of the adjacent ones of the plurality of springs that are strung side by side in the opening of the vehicle frame. If the pair of hook portions 22 is fitted to the two spring portions of the adjacent placement portion 21, a lower seat to be mounted in a plurality of springs, between the two springs It is placed.

[0036]

　The housing 3 includes a connector portion 31 connected to the vehicle control unit, and a switch housing portion 32 that is connected to the connector unit 31. Switch housing portion 32 has a bottom wall and the frame wall, a housing space for a load detection sensor 5 by the bottom wall and the frame wall is formed.

[0037]

　The bottom wall of the switch housing portion 32, is provided fixing pins 33 and connecting pins 34. Fixing pins 33 are pins for fixing the load sensor 5 to be accommodated in the housing 3. Connecting pins 34 are electrically connected to the connector terminal of the connector portion 31. The connection pin 34, the first electrode sheet 50 constituting the load sensor 5, of the second electrode sheet 60 and the spacer 70 is inserted into the first electrode sheet 50 serving as the lower side of the load detection sensor 5 Load detecting sensor 5 and is electrically connected. In FIG. 1, for convenience, the connector terminal of the connector portion 31 is omitted.

[0038]

　The outer surface of the frame wall of the switch housing portion 32 protruding piece 35 is provided at the lower end of the frame wall hooks 36 to be fitted into the through hole 23 of the base 2 is provided. If the hook piece 36 is fitted into the through hole 23 of the base 2, the housing 3 is fixed to the base 2.

[0039]

　The housing cover 4 is a cover member for covering the housing space of the switch housing portion 32 has a top wall and the frame wall. A pair of arms 41 is provided at the lower end of the frame wall of the housing cover 4, the opening 42 of the protruding piece 35 of the switch housing portion 32 of the housing 3 is fitted to the arm 41 is bored. Housing cover 4 is fixed to the housing 3 by projecting pieces 35 of the housing 3 with respect to the opening 42 of the pair of arms 41 is fitted.

[0040]

　The top wall of the housing cover 4, the switch pressing portion 43 which protrudes from the inner surface which is opposed to the bottom wall of the switch housing portion 32 of the housing 3 is provided. Switch pressing portion 43, when the housing cover 4 is fixed to the housing 3 is disposed with a switch portion and a gap of the load sensor 5.

[0041]

　Outer surface of the top wall of the housing cover 4 is a surface facing the lower surface of the vehicle seat. That is, the base 2 a lower vehicle seat is placed on the plurality of springs between the two springs are arranged, if the housing cover 4 to the housing 3 fixed to the base 2 is attached, the housing cover 4 is positioned at a lower surface and clearance of the vehicle seat. When a person in this case is seated on the vehicle seat, for the vehicle seat housing cover 4 is pressed depressed downward, switch portion of the load sensor 5 is pressed by the switch pressing portion 43 of the housing cover 4. As the material of the housing cover 4, polycarbonate (PC), polyamide (PA), polybutylene terephthalate (PBT), a phenol resin, resins such as epoxy resins include those obtained by incorporating a glass fiber to the resin.

[0042]

　Figure 2 is an exploded view showing the structure of a load detection sensor, FIG. 3 is a diagram showing a cross-section of the load sensor. Of (A) is specifically Figure 3 is a diagram showing a cross-section through the X-X in FIG. 2, (B) in FIG. 3 is a diagram showing a cross-section through the Y-Y of FIG.

[0043]

　As shown in FIGS. 2 and 3, the first electrode sheet 50 of the load sensor 5 has an insulating substrate 51 having no example flexibility. As the material of the substrate 51, and the like phenolic resin or epoxy resin. In this substrate 51 on one surface F1 which is opposite to the second electrode sheet 60, first electrode 52 and the first contact portion 53 is disposed.

[0044]

　The first electrode 52 is the one of the switching elements constituting the switch SW, for example, a circular metal printing layer. Incidentally, other switch elements constituting the switch SW is a second electrode 62 provided in the second electrode sheet 60 side.

[0045]

　The first contact portion 53 is a one of the members constituting the connection maintaining unit AP that electrical connection can be maintained even when no external pressure is applied to the load detection sensor unit 1 (in to FIG. 3 (B)) of, for example, is a metal printed layer. The first contact portion 53 of the present embodiment, the contact area AR1 in which the second contact portion 63 of the second electrode sheet 60 which is the other member constituting the connection maintaining unit AP contacts electrically to the contact area AR1 the second contact portion 63 is connected is composed of a non-contact area AR2 as a non-contact. Incidentally, external pressure is a pressure applied from the vehicle seat to the load sensor unit 1 in accordance with the seating of a person.

[0046]

　The other surface F2 opposite to the one surface F1 at the substrate 51 is the lower surface of the load sensor 5, the resistance 54 is disposed on the other surface F2. Resistor 54 is a resistor for detecting breakage, are electrically connected in parallel with the configured switch SW between the first electrode 52 and the second electrode 62. In this embodiment, resistor 54 is a chip resistor.

[0047]

　The substrate 51, sheet through-hole 55 penetrating from one surface F1 of the substrate 51 to the other surface F2 is formed. This sheet through hole 55, the first sheet through hole 55A, the second sheet through hole 55B, fixing through holes 55C, 55D and the pin hole 55E, include 55F.

[0048]

　The first sheet through hole 55A is a sheet through hole opening is positioned in the first region where the electrode 52 is disposed within the one surface F1 of the substrate 51. Inside the first sheet through hole 55A is provided with a first conductive member CPA, through the first conductive member CPA, circuit portion disposed on the other surface F2 of the substrate 51 and the first electrode 52 and are electrically connected.

[0049]

　The first conductive member CPA is provided along the inner peripheral surface of the first sheet through hole 55A, the air hole SP surrounded by the first conductive member CPA electrode through-hole provided in the first electrode 52 It communicates with the opening 71 of the spacer 70 via 52A. That is, the first sheet through hole 55A via the electrode through-hole 52A which penetrates the first electrode 52 has a first electrode 52 of an air hole SP in communication with the opening 71 between the second electrode 62 ing.

[0050]

　The first sheet through hole 55A in this way, not only holes to connect the circuit portion disposed on the first electrode 52 and the other surface F2 side is one disposed on the surface F1 of the substrate 51 only, the spacer 70 exhaust hole for discharging air in the opening 71 to the outside of the load sensor 5 also serves as.

[0051]

　The second sheet through hole 55B is a sheet through hole opened in the first region of the contact portion 53 is arranged is positioned among the one surface F1 of the substrate 51. In the present embodiment, the opening of the second sheet through hole 55B is positioned in the non-contact area AR2 of the first contact portion 53.

[0052]

　Inside the second sheet through hole 55B is filled with a second conductive member CPB, via the second conductive member CPB, circuit portion disposed on the other surface F2 of the substrate 51 and the first contact point part 53 and are electrically connected. Incidentally, the second conductive member CPB because it is filled in the second sheet through hole 55B, there is no space corresponding to the air holes SP of the first sheet through hole 55A.

[0053]

　Fixing through holes 55C, 55D (FIG. 2) is a through hole fixing pin 33 provided in the bottom wall of the switch housing portion of the housing 3 is inserted. The fixing through-holes 55C, the diameter of 55D is the outer diameter and the same degree of fixing pins 33.

[0054]

　Pin hole 55E, 55F is a through hole connecting pin 34 provided in the housing 3 is inserted. Terminal 5A is one end portion of an electric circuit is provided in the load sensor 5 in the inside of the pin hole 55E, the other end portion of the electric circuit of the load detection sensor 5 in the inside of the pin hole 55F terminal 5B is provided is. Terminals 5A, 5B is the corresponding pin hole 55E, it is provided along the inner peripheral surface of 55F, the width of the space surrounded the terminals 5A, and 5B is the outer diameter and the same degree of connection pins 34 that.

[0055]

　Second electrode sheet 60, the metal sheet 61, second electrode 62, and a second contact portion 63.

[0056]

　Metal sheet 61 is a thin metal sheet having flexibility, has a shorter vertical width than the longitudinal width of the substrate 51 in the present embodiment, thin rectangular parallelepiped having a width equal to the width of the substrate 51 It is. As the material of the metal sheet 61 is not particularly limited as long as it is metal, and the like for example stainless steel or copper.

[0057]

　The metal sheet 61, fixing through holes 65C penetrating from one surface of the metal sheet 61 to the other surface, 65D are formed. Fixing through holes 65C, 65D is a through-hole fixing pin 33 provided in the bottom wall of the switch housing portion of the housing 3 is inserted, fixing through-hole 55C formed in the substrate 51 of the first electrode sheet 50 , it is the 55D and the same shape and size.

[0058]

　The second electrode 62 is the other of the switching elements constituting the switch SW, in the present embodiment is a member which faces the first electrode 52 via a spacer 70 in the metal sheet 61. That is, part of the metal sheet 61 also serves as the second electrode 62. Incidentally, for example, a metal layer of the same material or different material as the metal sheet 61, the second electrode 62 may be disposed at a portion facing the first electrode 52 via a spacer 70 in the metal sheet 61.

[0059]

　The second contact portion 63 is one member constituting the connection maintaining unit AP, in the present embodiment is formed as a leaf spring.

[0060]

　That is, the metal in the sheet 61, a pair of notches 61A and 61B which extend toward the other end from one end of the metal sheet 61 (FIG. 1) is provided at a predetermined interval, these notches 61A and 61B ( site sandwiched Figure 1) is a second contact portion 63. Further, by the second contact portion 63 so as to be inclined with respect to the seat surface of the metal sheet 61 is folded on the side base of the second contact portion 63 is opposed to the spacer 70, the second contact portions 63 There is formed as a leaf spring. Site in this manner differs from the portion to be the second electrode 62 in the metal sheet 61 also serves as the second contact portion 63. The shape of the leaf spring which is formed as a second contact portion 63 is, for example, may be the root of the width larger trapezoidal shape than the width of the open end, is applicable various shapes other than a rectangle or a trapezoid is there.

[0061]

　Incidentally, fixing through-hole 65C of the second electrode sheet 60, and the placement site of the second electrode 62 and the second contact portion 63 with respect to 65D, fixing through-hole 55C of the first electrode sheet 50, first electrode 52 and against 55D the placement site of the first contact portion 53 is relatively the same positional relationship.

[0062]

　The spacer 70 includes a first electrode sheet 50 is an insulating member of thin sandwiched between the second electrode sheet 60, in the present embodiment is a metal sheet 61 and the same shape and size. As the material of the spacer 70 PET, like PI (polyimide) or the resin such as PEN is.

[0063]

　This spacer 70 opening 71 is formed. The opening 71 includes a first electrode 52 disposed on the substrate 51, a between the second electrode 62 of a metal sheet 61 which is opposite to the first electrode 52, first electrode 52 and the in the vertical direction It is disposed at a position overlapping the second electrode 62. The size of the opening 71 is slightly smaller state than the size of the first electrode 52.

[0064]

　Also the spacer 70 opening 72 slit is formed. The opening 72 includes a first contact portion 53 disposed on a substrate 51, a between the second contact portion 63 of the metal sheet 61 which is opposite to the first contact portion 53, the first contact in the vertical direction It is disposed at a position overlapping the part 53 and the second contact portion 63. The size of the opening 72 is slightly larger state than the size of the leaf spring which is formed as a second contact portion 63 in the metal sheet 61.

[0065]

　More spacer 70, fixing through holes 75C penetrating from one surface of the spacer 70 to the other surface, 75D are formed. Fixing through holes 75C, 75D is a through-hole fixing pin 33 provided in the bottom wall of the switch housing portion of the housing 3 is inserted, fixing through-hole 55C formed in the substrate 51 of the first electrode sheet 50 , it is the 55D and the same shape and size.

[0066]

　Incidentally, fixing through-hole 75C in the spacer 70, the arrangement site of the opening 71 and the opening 72 for 75D, fixing through-hole 55C of the first electrode sheet 50, the placement site of the first electrode 52 and the first contact portion 53 for 55D It is relatively the same positional relationship with.

[0067]

　Thus the first electrode sheet 50, and the second electrode sheet 60 and the load detection sensor 5 Spacers 70 are superimposed is formed. In the present embodiment, as shown in FIG. 1, the first pin hole of the electrode sheet 50 55E, is 55F are passed through a pair of connecting pins 34 of the housing 3. Thus the pin hole 55E, terminals 5A provided inside the 55F, 5B are in contact with the corresponding connection pins 34 are electrically connected to the connector terminal of the connector portion 31 of the housing 3 via the connection pin 34 that. Further, the fixing pin 33 in the housing 3 fixing through-hole 75C of the spacer 70, 75D and the second fixing through-hole of the electrode sheet 60 65C, 65D is passed sequentially. Then, one surface F1 of the substrate 51 is brought into contact with one surface of the spacer 70, in a state where one side of the metal sheet 61 is in contact with the other surface of the spacer 70, the first electrode sheet 50, the spacer 70 and second electrode sheet 60 is fixed to the fixing pin 33.

[0068]

　Note that the second contact portion 63 which constitutes the connection maintaining unit AP (to FIG. 3 (B)) in the load sensor 5 is in a state inclined at all times by plastic deformation to the sheet surface of the metal sheet 61. Therefore, if the spacer 70 is the first electrode sheet 50 and the second electrode sheet 60 are overlapped in a state of interposing the second contact portion 63 through the opening 72, is facing the second contact portion 63 It will continue to press the first contact portion 53. Thus, the connection maintaining unit AP, electrical connection state even when no external pressure is applied to the load detection sensor unit 1 and the first contact portion 53 and the second contact portion 63 is maintained.

[0069]

　Meanwhile, the first electrode sheet 50, the load sensor 5 to the second electrode sheet 60 and the spacer 70 are overlapped, when a person in the vehicle seat is seated, the switch pressing portion 43 of the housing cover 4 (Fig. 1) It is pressed against the second electrode sheet 60 side. In this case, the load detecting sensor 5, a metal sheet 61 of the second electrode sheet 60 is flexed so as to enter the opening 71 of the spacer 70, the first electrode 52 and the second electrode 62 which is opposed to each other through the opening 71 bet is to contact. As a result, the switch SW of the load sensor 5 is turned on, the circuit of the load detection sensor 5 is turned on. Thus, since the switch pressing portion 43 disposed on the switch SW of the load sensor 5 is pressed against the switch SW, it is possible to transmit the appropriate load via the switch pressing portion 43 to the load sensor 5.

[0070]

　Incidentally, the opening 71 of the spacer 70, as described above, the first sheet through hole 55A via the electrode through-hole 52A of the first electrode 52 is in communication (in Figure 3 (A)). Therefore, when the metal sheet 61 of the second electrode sheet 60 is flexed, air openings 71 is discharged to the outside of the load sensor 5 without staying in the opening. Thus, bending of the metal sheet 61 of the second electrode sheet 60 is avoided that such is suppressed by the air in the opening 71, the first electrode 52 tends second electrode 62 is in contact, the sensitivity of the load sensor 5 There will be improved.

[0071]

　Figure 4 is a diagram showing an equivalent circuit of the load sensor 5. As shown in FIG. 4, a pair of terminals 5A is a circuit terminal of the load sensor 5, between 5B, the switch SW (the first electrode 52 and the second electrode 62), connection maintaining unit AP (first contact parts 53 and the second contact portion 63) and is provided.

[0072]

　The switch SW is a pair of terminals 5A, electrically connected in series between 5B, the pair of terminals 5A, connector terminal 3A provided in the connector portion 31 of the housing 3 through 5B, is connected to 3B. The resistance 54 to the switch SW is electrically connected in parallel.

[0073]

　As described above, the load sensor unit 1 of this embodiment includes a spacer 70 disposed between the first electrode sheet 50, and the second electrode sheet 60 and the first electrode sheet 50 and the second electrode sheet 60 there. The first electrode sheet 50 is one of the first electrode 52, and has a first contact portion 53, the second electrode 62 and the second electrode sheet 60 is opposed to the first electrode 52, and the first contact portion 53 having opposed by the second contact portion 63 is electrically connected to the second electrode 62. The spacer 70 has at least a first electrode 52 and the opening 71, 72 and between the between the first contact portion 53 and the second contact portion 63 of the second electrode 62.

[0074]

　Further, the first electrode 52 is switch SW is composed of a second electrode 62, connection maintenance portion even when the first contact portion 53 is not external pressure applied by the second contact portion 63 is electrically connected is maintained AP is configured. The serial number of the switch SW to be connected electrically in series between one terminal 5A and the other terminal 5B at the load sensor 5 is taken as one.

[0075]

　In such a load sensor unit 1, a first contact portion 53 of the first electrode sheet 50 and the circuit portion formed on the first electrode sheet 50 via the second contact portion 63 of the second electrode sheet 60 second a circuit portion which is formed on the second electrode sheet 60 is always in continuity state. Therefore, it is possible to arrange the respective pair of terminals 5A, 5B to the first electrode sheet 50. Thus, the load sensor unit 1 capable of placing a pair of terminals to the first electrode sheet 50 is provided.

[0076]

　In this embodiment, a portion including the second contact portion 63 in the second electrode sheet 60 is a plate spring that presses the second contact portion 63 to the first contact portion 53.

[0077]

　Accordingly, since even without other member can be maintained between the first contact portion 53 and the second contact portion 63 is always connected state, it is possible to prevent a connection failure. Also, when the first contact portion 53 and the second contact portion 63 are connected only by the leaf spring, because the other member to press the second contact portion 63 to the first contact portion 53 is avoided, parts correspondingly score is reduced, it can be miniaturized.

[0078]

　In this embodiment, the second electrode sheet 60 is formed of a metal sheet 61. Therefore, since there is less affected by the heat in the second electrode sheet 60, be used in a high temperature environment reduction and a low-temperature environment, the sensitivity of the load sensor 5 is stabilized. Further, since the second electrode sheet 60 is a metal, it is possible to reduce the damage, it is possible to improve the durability. Furthermore, since the second contact portion 63 which is a plate spring in the second electrode sheet 60 is also a metal, a second contact portion of the resin sheet as compared with the case where the leaf springs are formed as the leaf spring malleability and ductility of the part 63 can be increased. Therefore, it is possible to reduce the damage, such as the second contact portion 63 formed as a leaf spring is broken, to improve the durability of the leaf spring.

[0079]

　In the case of this embodiment, a substrate 51 made of a sheet of the first electrode sheet 50 has a first sheet through hole 55A that penetrates from one surface F1 which is opposite to the second electrode sheet 60 to the other surface F2 . The first electrode 52, through the first conductive member CPA provided in the first sheet through hole 55A, and is the other connection circuit part and electrically disposed on the surface F2 of the substrate 51.

[0080]

　Therefore, it is possible to take out one of the terminals 5A on the other surface F2 of the substrate 51. As in the present embodiment, it is possible to the first sheet through hole 55A to place the terminal 5A inside another pin hole 55E. Therefore, the simplified when connecting the load sensor unit 1 and other electronic parts, such as connectors 31. Moreover, since it is possible to provide a circuit portion on the other side F2, it is not necessary to provide a circuit portion on one surface F1, it is possible to reduce the unevenness by the circuit portion of one surface F1. Thus, it is possible to stabilize the sensitivity of the load sensor 5.

[0081]

　Furthermore, in the case of this embodiment, one side of the opening in the first sheet through hole 55A is located in the region where the first electrode 52 is arranged at one surface F1 of the substrate 51. The first sheet through hole 55A via the electrode through-holes 52A provided in the first electrode 52 has an air hole SP in communication with the opening 71 between the first electrode 52 and the second electrode 62.

[0082]

　Therefore, the first sheet through hole 55A is, one of the first electrode 52 disposed on the surface F1, the other circuit portions on the side electrically connected hole for connection of the substrate 51 of the substrate 51 not only, so that also serves as an exhaust hole for discharging air of the spacer to the outside. Therefore, it is possible to improve the durability of the substrate 51 as compared with the case where the the connecting hole and the exhaust hole separately. Moreover, it is not necessary to provide the exhaust holes separately, it is possible to save space.

[0083]

　Furthermore, in the case of this embodiment, a substrate 51 made of a sheet of the first electrode sheet 50, a position different from the first sheet through hole 55A, the other surface F2 from one side F1 which is opposite to the second electrode sheet 60 a second sheet through hole 55B penetrating to the. The first contact portion 53, via the second conductive member CPB provided in the second sheet through hole 55B, which is the other of the connecting circuit part and electrically disposed on the surface F2 of the substrate 51.

[0084]

　Therefore, it is possible to retrieve a pair of terminals 5A, 5B on the other surface F2 of the substrate 51. As in the present embodiment, the first sheet through hole 55A and the through-holes 55E for another pin, it is also possible to arrange terminals 5A, and 5B in the interior of 55F. Therefore, the simplified when connecting the load sensor unit 1 and other electronic parts, such as connectors 31. Moreover, since it is possible to provide a circuit portion on the other side F2, it is not necessary to provide a circuit portion on one surface F1, it is possible to reduce the unevenness by the circuit portion of one surface F1. Thus, it is possible to stabilize the sensitivity of the load sensor 5.

[0085]

　Further in this embodiment, it is disposed on the other surface F2 of the substrate 51, and a resistor 54 which connects the first electrode 52 and the first contact portion 53. Therefore, even if the thickness of the resistor 54 is large, it is possible to prevent the sensitivity of the load sensor unit 1 by its thickness is deteriorated.

[0086]

　In the present embodiment, the second electrode sheet 60 circuit sites and a resistor 54 in provided on the other surface F2 of the substrate 51, a pair of terminals 5A, 5B are provided pin hole 55E, in the 55F . Therefore, the first electrode 52 on one surface F1 of the substrate 51, and, almost no components other than the first contact portion 53, there is no unevenness due to other components, the sensitivity of the load sensor unit 1 is further improved.

[0087]

(2) Second Embodiment
　will be described in detail with reference to the accompanying drawings a second embodiment for implementing the present invention. However, components such as the first embodiment and the same or similar among the components of the load sensor unit in the second embodiment are denoted by the same reference numerals, and a duplicate description thereof will be omitted as appropriate.

[0088]

　Figure 5 is an exploded view showing the structure of a load detection sensor in the second embodiment. Figure 6 is a diagram showing a cross section of line Z-Z in FIG. Figure 7 is a diagram showing an equivalent circuit of the load sensor in the second embodiment.

[0089]

　In the first embodiment, as shown in FIG. 4, the number of switch SW in the load sensor 5 have been considered one, electrically connected in series a pair of terminals 5A of the load detection sensor 5, between 5B the number of series that switch SW was one.

[0090]

　In contrast, in the present embodiment, as shown in FIG. 7, the number of switches in the load sensor 5 is 4 Tsutosa. Since these switches SW1 ~ SW4 are connected in parallel, so that each said switches SW1 ~ SW4 are electrically connected in series a pair of terminals 5A of the load sensor 5, between 5B. That is, in this embodiment, the number of switches in the load sensor 5 is more, the load pair of terminals 5A detection sensor 5, the series number of switches that are electrically connected in series between 5B 1 Tsutosare that.

[0091]

　Incidentally, one of the switching elements constituting the switch SW1 ~ SW4 is a first electrode 82A ~ 82D, other switch elements constituting the switches SW1 ~ SW4 are second electrodes 92A ~ 92D.

[0092]

　In the first embodiment, as shown in FIGS. 1 and 3, at a second electrode sheet 60 and the gap of the load sensor 5, one switch located above the switch SW of the load sensor 5 the pressing portion 43 is provided on the top wall of the housing cover 4.

[0093]

　In contrast, in the present embodiment, instead of the switch pressing portion 43, at a second electrode sheet 60 and the gap of the load sensor 5, respectively located above the respective switches SW1 ~ SW4 of the load sensor 5 four switch pressing portion (not shown) is provided in the top wall of the housing cover 4.

[0094]

　In the first embodiment, as shown in FIG. 2, the flexible insulating substrate 51 having no is employed as a sheet of the first electrode sheet 50, the metal sheet 61 as the sheet of the second electrode sheet 60 It had been adopted. The different part of the metal sheet 61 is a second electrode 62 and the second contact portions 63.

[0095]

　In contrast, in the present embodiment, as shown in FIG. 5, the first insulation sheet 81 having flexibility as a sheet of the first electrode sheet 50 is employed, the flexibility as a sheet of the second electrode sheet 60 the second insulating sheet 91 having is employed. As the material of the first insulation sheet 81 and the second insulating sheet 91, PET, include resins, such as PI or PEN.

[0096]

　Second electrodes 92A ~ 92D to be part facing the first electrode 82A ~ 82D via a spacer 70 for example with a metal printing layer are respectively provided in the second insulating sheet 91. The second contact portion 93 comprising a portion facing the first contact portion 83 via a spacer 70 for example with a metal printed layer in the second insulating sheet 91 is provided. And the second contact portion 93 and the first contact portion 83 is shaped and of the same order of magnitude.

[0097]

　In the first embodiment, as shown in (B) of FIG. 3, the second contact portion 63 provided in the site containing the edge of the metal sheet 61 is a plate spring. The second contact portion 63 of the leaf spring continues to push the first contact portion 53, electrical also when no external pressure is applied to the load detection sensor unit 1 and the first contact portion 53 and the second contact portion 63 connection state is maintained.

[0098]

　In contrast, in the present embodiment, as shown in FIG. 6, the first contact portion 83 and a second contact portion 93 at least covering a state in which the first contact portion 83 and the second contact portion 93 is in contact the covering member 120 is provided to fixed. The covering member 120 is provided, for example, by molding, a first contact portion 83 which is in physical contact with the cover member 120 and the second contact portion 93 is fixed and maintained. Therefore, simply connected between the first contact portion 83 and the second contact portion 93 as compared with the case of the first embodiment to press a plate spring is maintained more further firmly. Thus, for example, sites pressing the second contact portion 93 with respect to the first contact portion 83 due to vibration of the vehicle seat is displaced, that the first contact portion 83 and the second contact portion 93 is disconnected it can be reduced. In FIG. 5, for convenience, the covering member 120 is omitted.

[0099]

　In the first embodiment, as shown in FIG. 3, the pin hole 55E, 55F are provided on the substrate 51, the pin hole 55E, terminals 5A along the inner circumferential surface of the 55F, 5B are provided It is to have. These terminals 5A, 5B, the connector terminal 3A through the connection pin 34 which is inserted the pin hole 55E, the 55F, was connected with 3B.

[0100]

　In contrast, in the present embodiment, as shown in FIG. 5, the pin hole 55E, 55F is omitted, among the one surface F1 of the first insulation sheet 81, the terminal in the area AR which is not covered by the spacer 70 5A, 5B are provided. As shown in FIG. 6, the terminal 5A, the 5B is connected to one end of a lead wire 200 through the lead wire 200, the connector terminal 3A connected to the other end of the lead wire 200, 3B and the terminal 5A, 5B and are electrically connected.

[0101]

　In the present embodiment, one end of the terminal 5A of the lead wire 200, the connection portion between 5B, the cover member 120 described above, is covered with the first contact portion 83 and the second contact portions 93. Therefore, not only by the covering member 120 and the first contact portion 83 only connection between the second contact portion 93, one end of the terminal 5A of the lead wire 200, the connection to the 5B is maintained more further firmly. In addition, it is also possible to suppress such contamination external static electricity. The first sheet through hole 55A, the second sheet through hole 55B and the pin hole 55E, since 55F is omitted, the durability of the first insulation sheet 81 only omitted min the through-hole is improved.

[0102]

　In the first embodiment, as shown in FIG. 2, the first sheet through hole 55A via the electrode through-hole 52A of the first electrode 52 is communicated with the opening 71 of the spacer 70, the first sheet through hole 55A There was also serves as an exhaust hole not only holes for electrical connection.

[0103]

　In contrast, in the present embodiment, as shown in FIG. 5, the electrode through-hole 52A is not provided on the first electrode 82A ~ 82D. Further, the first sheet through hole 55A separately exhaust holes 85 are provided in the first insulation sheet 81, openings 101A ~ 101E of the spacer 70 to the first insulation sheet 81 is communicated.

[0104]

　That is, the spacer 70 of this embodiment includes a first electrode 82A ~ 82D, a between the second electrode 92A ~ 92D which are opposed to the first electrode 82A ~ 82D, the first electrode 82A ~ 82D and the opening 101A ~ 101D are formed in the position overlapping the second electrodes 92A ~ 92D and a vertical direction. Further, the first contact portion 83 a between the second contact portion 93, an opening 101E is formed at a position overlapping in the vertical direction with the first contact portion 83 and the second contact portions 93. The opening 101E is an opening for allowing physical contact with the first contact portion 83 and a second contact portion 93, the first electrode sheet 50 and the second electrode sheet 60 are superimposed in a state where the spacer 70 is interposed when, in a state in which with the first contact portion 83 is closed by the second contact portion 93. The opening 101E corresponds to the slit-like opening 72 in the first embodiment.

[0105]

　More spacer 70, communicating slits 102A ~ 102D for communicating the openings 101A ~ 101E each other are formed. Communicating slit 102A communicates the opening 101A and 101B to each other corresponding to the switches SW1 and SW2 are adjacent is connected in series. Communicating slit 102B communicates the opening 101B and 101C to each other corresponding to the switches SW2 and SW3 are adjacent is connected in series. Communicating slit 102C communicates the opening 101D and the communication slit 102B corresponding to the switch SW4. Communicating slit 102D communicates the opening 101E and the communication slit 102A formed between the first contact portion 83 and the second contact portions 93. The example aperture 101A of such an opening 101A ~ 101E, exhaust slit 103 for connecting the exhaust holes 85 of the first insulation sheet 81 is formed.

[0106]

　In the first embodiment, as shown in FIGS. 3 and 4, resistor 54 made of a chip resistor on the other surface F2 of the substrate 51 is disposed, is the resistor 54 is connected in parallel with the switch SW It was.

[0107]

　In contrast, in the present embodiment, as shown in FIG. 6, the resistor 84 made in one printing face F1 resistance of the first insulation sheet 81 is disposed, the resistor 84 is in parallel with the switches SW1 ~ SW4 It is connected. Thus, in this embodiment, the load sensor 5 is thinned in comparison with the first embodiment. The resistor 84 is covered by the first insulating sheet 81 and the spacer 70, to be housed inside the load detecting sensor 5, the resistance of the first embodiment is disposed on the outer surface of the load detection sensor 5 54 effects such as static electricity is reduced as compared to the.

[0108]

　The load detection sensor of the present embodiment, as in the first embodiment, the first contact portion 83 and the second contact portion 93 is in a state external pressure which is electrically connected even if not applied . Further, the load detection sensor of the present embodiment, a pair of terminals 5A, the number of series switches that are electrically connected in series between 5B is one, is an odd number.

[0109]

　Thus, formed in the first contact portion 83 and the second insulating first circuit portion formed in the insulating sheet 81 and the second insulating sheet 91 via the second contact portion 93 of the seat 91 of the first insulation sheet 81 and a circuit portion that is always made conductive state. Therefore, as in the first embodiment, it can be disposed a pair of terminals 5A, respectively 5B on the first insulating sheet 81.

[0110]

　(3) Other embodiments
　above, the first and second embodiments have been described as an example. However, the present invention is not limited to the above embodiment.

[0111]

　For example, in the above embodiment, a pair of terminals 5A, the number of series switches that are electrically connected in series between 5B was considered one. However, if the number of series is an odd number, it may not be one. Unless the number of series is an odd number, as in the above embodiment, it is possible to place the terminal 5A is a pair of terminals of the circuit in the load detecting sensor, a 5B to the first electrode sheet 50 side. As described above, when two or more switches in the circuit of the load sensor 5 is connected in parallel, each switch of the switch group connected to the parallel connected in series between a pair of terminals 5A, 5B It is is will be. Therefore, the number of switches even more, becomes one as serial number of switches connected to a pair of terminals 5A, the electrical series between 5B in the switch group.

[0112]

　In the above first embodiment, the metal sheet 61 is employed as a sheet of the second electrode sheet 60. However, PET, a resin sheet such as a PI or PEN may be employed in place of the metal sheet 61. The resin sheet and the second electrode 62, since the second contact portion 93 and the second electrode 62 can not serve as a circuit connecting the second contact portion 93, the first such on one surface of the resin sheet for example, a metal printing layer 2 electrodes 62, the circuit is provided for connecting the second contact portion 93 and the second electrode 62 and the second contact portion 93. Also in this case the same effect as the first embodiment. However, as described above, since the resin sheet tends to malleability and ductility is reduced as compared with the metal sheet 61, thereby reducing the damage such as the second contact portion 63 formed as a leaf spring is broken durability in view of improving the the metal sheet 61 is preferred.

[0113]

　In the first embodiment, a pair of terminals 5A, 5B is the pin hole 55E, but provided within the 55F, one surface F1 or the other of the pair on the face F2 of the terminal 5A of the substrate 51, 5B may be provided.

[0114]

　In the above second embodiment, the first insulating sheet 81 as the sheet of the first electrode sheet 50 is employed, the second insulating sheet 91 is employed as a sheet of the second electrode sheet 60. However, the second insulation sheet 91 may be a metal sheet. In this case, as in the case of the metal sheet 61 of the first embodiment, the second electrodes 92A ~ 92D and a second contact portion 93 for also serves as a metal sheet, the number of parts can be reduced.

[0115]

　In the above second embodiment, the second contact portion 93 was not formed in a plate spring, it may be the second contact portion 93 as in the first embodiment as a leaf spring.

[0116]

　In the above second embodiment, the first contact portion 83 and the second contact portion 93 is covered by a covering member 120. However, in place of the covering member 120, as shown in FIG. 8, the surface facing the first electrode sheet 50 in the second electrode sheet 60 from the opposite side, through the second electrode sheet 60 second pressing member 300 for pressing the second contact portion 93 to the first contact portion 83 may be provided. Further, the surface facing the second electrode sheet 60 in the first electrode sheet 50 from the opposite side, the pressing member for pressing the first contact portion 83 via the first electrode sheet 50 to the second contact portion 93 it may be provided. Furthermore, both may be provided with a pressing member for the pressing together of the first electrode sheet 50 and the second electrode sheet 60. In short, the first electrode sheet 50 is pressed against at least one of the second electrode sheet 60, a first contact portion 83 and the second contact portion 93 may be a pressing member for maintaining a state of contact. If such pressing members are provided, the second contact portion 93 may not be be a leaf spring. One end and the terminal 5A of the lead wire 200, the connection portion between 5B are fixed, for example, by soldering or the like. Further, the pressing member 300 or the aforementioned cover member 120 may be provided in the first embodiment.

[0117]

　In the above first embodiment is provided resistor 54 made of a chip resistor, it said although the resistance 84 consisting of a printed resistor provided in the second embodiment, the resistor 54, 84 may be omitted. The resistor 54, 84 may be provided in plurality.

[0118]

　In the above first embodiment, it separates the second electrode sheet 60 and the gap of the load sensor 5, the switch pressing portion 43 to the switch SW of the load detection sensor 5 is arranged. In the above second embodiment, at a second electrode sheet 60 and the gap of the load sensor 5, the switch pressing portion upward of the switches SW1 ~ SW4 of the load detection sensor 5 is arranged. However, in contact with state to the second electrode sheet 60 of the load sensor 5, the switch pressing portion above each switch SW, SW1 ~ SW4 may be disposed. In short, if the switch pressing portion disposed on the switch SW, SW1 ~ SW4.

[0119]

　In the above first embodiment, although recess for accommodating the resistor 54 is not provided in the bottom wall of the switch housing portion 32, the recess may be provided in the bottom wall of the switch housing portion 32.

[0120]

　In the above embodiment, the base 2, the housing 3 and the housing cover 4 is provided. However, for example, when a load sensor is disposed in the seat pan of the vehicle seat, the seat 2, all or part of the housing 3 and the housing cover 4 may be omitted. Further, the load detection sensor of the present embodiment may be used in applications other than the sensor that detects the seating of a vehicle seat. Note that the in case of omitting the housing 3 and the housing cover 4 in the second embodiment, in a state where the first contact portion 83 and the second contact portion 93 is contacted, it is preferably covered by a covering member 120 as described above. In the case of omitting the housing cover 4, the switch pressing portion 43 or the pressing member 300 is provided, for example, such as the lower surface portion of the vehicle seat.

[0121]

　Incidentally, each component in the load detection sensor unit 1, the first embodiment described above, in addition to the content shown in the second embodiment and other embodiments, as appropriate, in combination without departing from the present purposes, omitted, changes, it is possible to make and addition of known techniques.

[0122]

　The present invention has applicability unless provided in place to detect the load. For example, there is a possibility available to the vehicle seat and care for the bed of a vehicle or the like, there is a particular availability for the seat should wear a seat belt.

DESCRIPTION OF SYMBOLS

[0123]

　1 ... load sensor unit
　2 ... pedestal
　3 ... housing
　4 ... housing cover
　5 ... load detection sensor
　50 ... first electrode sheet
　51 ... substrate
　52,82A ~ 82D · · first electrode
　53,83 ... first contact portion
　54, 84 ... resistor
　55 ... sheet through hole
　60 ... second electrode sheet
　61 ... metal sheet
　62,92A ~ 92D ·· · second electrode
　63,93 ... second contact portion
　70 ... spacer
　71,72,101A ~ 101E ··· opening
　81 ... first insulation sheet
　85 ... exhaust holes
　91 ... first 2 the insulating sheet
　102A ~ 102D ... communicating slit
　103 ... exhaust slit
　120 ... cover member
　200 ... lead
　300 ... pressing member

The scope of the claims

[Claim 1]

　At least one or more of the first electrode, and a first electrode sheet having a first contact portion,
　the second electrode being opposed to the first electrode, and the second electrode electrically is opposed to the first contact portion with the second electrode sheet having a second contact portion to be connected to,
　the first electrode sheet and disposed between the second electrode sheet, wherein the period of at least the first electrode and the second electrode and the first a spacer having an opening and between the contact portion and the second contact portion,
　one terminal which is electrically connected to the first electrode,
　and the other terminal electrically connected to said first contact portion
the provided,
　the switch is a first electrode and the second electrode are configured, the connection maintaining unit is said the first contact portion is electrically connected to the case where external pressure is not applied between the second contact portion is maintained configured,
　electrically contacts in series between the one terminal the other terminal Series number of the switch is the odd number is
the load sensor, characterized in that.

[Claim 2]

　The site containing the second contact portion in the second electrode sheet is a plate spring that presses the second contact portion to the first contact portion
a load sensor according to claim 1, characterized in that.

[Claim 3]

　The second electrode sheet is formed of a metal sheet
load detection sensor according to claim 1 or 2, characterized in that.

[Claim 4]

　Against at least one of the first electrode sheet and the second electrode sheet, wherein the first contact portion and second contact portion pressing member to remain in contact
claim 1, further comprising a load detecting sensor according to any one-third aspect.

[Claim 5]

　Covering at least the second contact portion of the first contact portion and the second electrode sheet in the first electrode sheet, covering member for fixing the state of said first contact portion and second contact portion are in contact
further load detecting sensor according to any one claims 1 to 3, characterized in that it comprises.

[Claim 6]

　The first electrode sheet has a first sheet through hole penetrating from one surface to be opposed to the second electrode sheet to the opposite other surface and one surface,
　said first electrode, through the first conductive member provided in the first sheet through hole, wherein the other surface to the circuit portion electrically connected to be arranged
according to claim 5 any one of claims 1, characterized in that load detection sensor according to.

[Claim 7]

　Said first of said one side of the sheet through hole opening, the is positioned in the region where the first electrode is arranged on one surface,
　the first sheet through hole electrode provided on the first electrode through the through-hole has an air hole that communicates with the opening between the second electrode and the first electrode
load detection sensor according to claim 6, characterized in that.

[8.]

　The first electrode sheet has the position different from the first sheet through hole, the second sheet through hole penetrating from the one surface to be opposed to the second electrode sheet to the other surface,
　wherein the first contact portion, said through second conductive member provided in the second sheet through hole, wherein the other surface to the circuit portion electrically connected to be arranged
claim 6, wherein the or load detecting sensor according to claim 7.

[Claim 9]

　Wherein disposed on the other side, having electrically connecting resistance between the first electrode and the first contact portion
load detection sensor according to claim 8, characterized in that.

[Claim 10]

　Wherein arranged on one side, it has a printed resistor for connecting the first electrode and the first contact portion electrically
load detecting sensor according to any one of claims 1 to 8, wherein the.

[Claim 11]

　A load detecting sensor according to any of claims 1 to 10,
　disposed on the switch, and the switch pressing portion for pressing the switch when the external pressure is applied
the load sensor unit, characterized in that it comprises a.

[Claim 12]

　The load sensing sensor unit,
　a housing having an accommodation space for accommodating the load detecting sensor,
　a housing cover for covering the accommodation space
comprises a,
　the switch pressing unit is provided on the housing cover
claims, characterized in that load detecting sensor unit according to claim 11.