Claims:[0056] Claims:
We claim:
1) An electromagnetic switching apparatus for start/stop starter motor, the apparatus comprising:
a) a plurality of solenoids, wherein one solenoid comprises pinion movement arrangement (200), and another solenoid comprises of contact closure and inrush current reduction arrangement (100);
b) the pinion movement solenoid comprising:
a. an outer sleeve (207), wherein the outer sleeve (207) rigidly fixed to a starter motor frame (601);
b. an electromagnetic coil (201) arranged in a bobbin (206), wherein the bobbin (206) is arranged in axial direction to the outer sleeve (207) at one end;
c. a nonmagnetic plate (205) fixed at the other end of the outer sleeve (207) in axial direction;
d. a plunger (202) arranged in an inner circumference of the electromagnetic coil (201) which moves in axial direction towards the core plate (204);
e. a shift lever (701) connected to the plunger (202) at one end through an operating rod (203) and another connected to the pinion (702);
c) the contact closure and inrush current reduction solenoid (100) comprising:
a. an outer sleeve (112), wherein the outer sleeve (112) is rigidly fixed to the starter motor frame (601) adjacent to the pinion movement solenoid (200);
b. a first electromagnetic coil (111) placed in a first bobbin (113), wherein the first bobbin (113) is arranged in axial direction to the outer sleeve (112);
c. a first core plate (103) placed after the first bobbin (113);
d. a second core plate (109) arranged after the second bobbin (114) in axial direction;
e. a first plunger (102) arranged in an inner circumference of the first electromagnetic coil (111) which moves in axial direction towards the first core plate (103);
f. a nonmagnetic material spindle (107) connected to one end of the second plunger (104);
g. the nonmagnetic material spindle (107) is integrally connected to the second plunger (104), wherein the spindle (107) carries two moving contact plates (105a and 105 b), which are arranged at an offset distance;
h. a terminal base (106) containing plurality of sets of fixed contact terminals which are arranged rigidly to the outer sleeve (112) in axial direction, wherein the first set of two terminals, one terminal is connected to battery terminal and another terminal is interconnected to a third terminal of the second set, and the second set of two terminals, wherein one terminal is connected to starter motor and another terminal is interconnected with the terminal of the first set of terminals via a high resistance material.
2) The apparatus as claimed in claim 1, wherein the pinion movement solenoid and the contact closure and inrush current reduction solenoid are rigidly fixed to the engine.
3) The apparatus as claimed in claim 1, wherein said high resistance is added during cranking and after a predefined time the high resistance is removed, wherein the high resistance is added and removed using the second plunger (104).
4) The apparatus as claimed in claim 1, wherein said high resistance material (305) reduces inrush current during the cranking process.
5) The apparatus as claimed in claim 1, wherein said shift lever arrangement increases the acceleration of the pinion movement.
6) The apparatus as claimed in claim 1, wherein said plunger (202) move away from the fixed non-magnetic plate (205).
7) The apparatus as claimed in claim 1 wherein the first electromagnetic and the second electromagnetic coil are single winding coils.
8) The apparatus as claimed in claim 7, wherein the plunger air gap required for pinion movement in the shift lever arrangement decreases as the shift lever ratio increases.
9) The apparatus as claimed in claim 1, wherein said pinion movement and contact assembly have independent operations.
, Description:[0001] DESCRIPTION OF THE INVENTION:
[0002] The following specification particularly describes the invention and the manner in which it is to be performed:
[0003] Technical field of the invention
[0004] The present invention relates an electromagnetic switching apparatus for start/stop starter motor, which has separate pinion movement and contact closure to have an independent operation. The present invention also relates to producing faster pinion movement operating at a small air gap and to add and remove the high resistance to reduce inrush current during cranking.
[0005] Background of the invention
[0006] Generally, in the starting devices for engines, a motor circuit is energized through an electromagnetic switch. When solenoid is energized, plunger moves and pinion gets meshed with the ring gear via lever. At this moment, the motor is energized by connecting the starter terminal and battery terminal using a movable contact plate. During this, a huge amount of current is drawn by starter motor from battery.
[0007] Various types of conventional starting devices for engines are known in the prior art, wherein most of them use the devices in which the pinion movement and contact closure are aligned in same line, axially and are dependent on each other for operation.
[0008] In the existing starting devices for engines, a huge amount of current is drawn by starter motor from battery during cranking process, which in return reduces the shelf life the motor.
[0009] Also, in the existing starting devices, two separate solenoids for contact closure and inrush current reduction are used, which have a loss wire to connect the contact closure and inrush current reduction solenoids. This loss wire leads to failure due to vibration and shock. The pinion movement arrangements in the current systems enable a slower rate (acceleration) pinion movement at the pinion side. Since the lever ratio is smaller, hence plunger air gap for pinion movement is larger.
[0010] Hence, there is need of a starting device with a system that has single structure contact closure operation and inrush current reduction technique, which eliminates the loss wire connection between contact closure operation and inrush current solenoids. The system must also eliminate pinion movement with slow rate (acceleration) and large air gap.
[0011] Summary of the invention
[0012] The present invention overcomes the drawbacks in the prior art and provides an electromagnetic switching apparatus for start/stop starter motor, wherein a single structure with contact closure operation and also inrush current reduction technique is employed. In the present invention the plunger air gap required for pinion movement is small. Both the pinion movement and contact closure operate independently in the present invention. Also, in the present invention a high resistance is added during cranking and after a predefined time the high resistance is removed. Therefore the pinion movement and contact closure have an independent operation, and the in rush current is reduced.
[0013] The present invention comprises of a plurality of solenoids, wherein one solenoid comprises pinion movement arrangement, and another solenoid comprises of contact closure and inrush current reduction arrangement.
[0014] In one embodiment of the present invention, an electromagnetic switching apparatus for start/stop starter motor comprises a pinion movement solenoid, wherein the pinion movement solenoid comprises an outer sleeve, wherein the outer sleeve is rigidly fixed to a starter motor frame. An electromagnetic coil is arranged in a bobbin, wherein the bobbin is arranged in axial direction to the outer sleeve at one end. The core plate is fixed at the other end of the outer sleeve in axial direction and a plunger is arranged in an inner circumference of the electromagnetic coil, which moves in axial direction towards the core plate. The shift lever is connected to the plunger at one end through an operating rod and another connected to the pinion.
[0015] According to another embodiment of the invention, the electromagnetic switching apparatus for start/stop starter motor comprises of a contact closure and inrush current reduction solenoid, wherein the contact closure and inrush current reduction solenoid comprises of an outer sleeve, wherein the outer sleeve is rigidly fixed to the starter motor frame at the side of the pinion movement solenoid. A first electromagnetic coil is placed in a first bobbin, wherein the first bobbin is arranged in axial direction to the outer sleeve. A first core plate is placed after the first bobbin and a second core plate is arranged after the second bobbin in axial direction. The first plunger is arranged in an inner circumference of the first electromagnetic coil, which moves in axial direction towards the first core plate.
[0016] Further, a nonmagnetic material spindle is connected to one end of the second plunger. The nonmagnetic material spindle is integrally connected to the second plunger, wherein the spindle carries two moving contact plates, which are arranged at an offset distance. The terminal base containing plurality of sets of fixed contact terminals are arranged rigidly to the outer sleeve in axial direction. In the first set of two terminals, one terminal is connected to battery terminal and another terminal is interconnected to a third terminal of the second set. In the second set of two terminals, one terminal is connected to starter motor and another terminal is interconnected with the terminal of the first set of terminals via a high resistance.
[0017] According to preceding embodiments of the invention, the said shift lever arrangement accelerates pinion movement at a fast rate and the plungers move away from the non-magnetic plate. The shift lever ratio is higher because of pivoting the lever at the top, the plunger air gap required for pinion movement is small. The pinion movement and contact assembly have independent operations.
[0018] According to preceding embodiments of the invention, the high resistance is added during cranking and after a predefined time, the high resistance is removed, wherein the high resistance is added and removed using the second plunger, wherein said high resistance reduces inrush current during the cranking process.
[0019] The invented electromagnetic switching apparatus uses a shift lever, wherein the top end of the shift lever is pivoted to the starter motor. Hence, the pinion movement accelerates at a fast rate. In the present invention, since the shift lever ratio is high, the plunger air gap required for pinion movement is small. Both the pinion movement and contact closure operate independently in the present invention. The present invention also uses an inrush current reduction technique, wherein the high resistance is added during cranking and after a predefined time the high resistance is removed. Hence, the high resistance material reduces inrush current during the cranking process. In the present invention, since the inrush current is reduced, the shelf life of the starter motor is increased.
[0020] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
[0021] Brief description of the drawings:
[0022] The foregoing and other features of embodiments will become more apparent from the following detailed description of embodiments when read in conjunction with the accompanying drawings. In the drawings, like reference numerals refer to like elements.
[0023] Figure 1 shows a cross sectional view of the contact closure and inrush current reduction solenoid, according to one embodiment of the invention.
[0024] Figure 2 shows a cross sectional view of the pinion movement solenoid, according to one embodiment of the invention.
[0025] Figure 3 shows a cross sectional view of the terminal base assembly, according to one embodiment of the invention.
[0026] Figure 4 shows a circuit diagram of an electromagnetic switching apparatus for start/stop starter motor, according to one embodiment of the invention.
[0027] Figure 5 shows a perspective view of arrangement of pinion movement solenoid, and contact closure and inrush current reduction solenoid, according to one embodiment of the invention.
[0028] Figure 6 shows a side view of arrangement of pinion movement solenoid, and contact closure and inrush current reduction solenoid, according to one embodiment of the invention.
[0029] Figure 7 shows the front view of the arrangement of pinion movement solenoid with starting motor via shift lever, according to one embodiment of the invention.
[0030] Detailed description of the invention:
[0031] Reference will now be made in detail to the description of the present subject matter, one or more examples of which are shown in figures. Each embodiment is provided to explain the subject matter and not a limitation. These embodiments are described in sufficient detail to enable a person skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, physical, and other changes may be made within the scope of the embodiments. The following detailed description is, therefore, not be taken as limiting the scope of the invention, but instead the invention is to be defined by the appended claims.
[0032] The term “Shift lever ratio” as claimed in the embodiments refers to the ratio of the distance between the pivot and the pinion to the distance between the operating rod and the pivot.
[0033] The present invention provides an apparatus for electromagnetic switching in a starter motor. The present invention comprises of a single structure having contact closure operation and also inrush current reduction technique is employed. The single winding coil is used for the operation of pinion movement and contact closure. In the present invention, the plunger air gap required for pinion movement is small. Both the pinion movement and contact closure operate independently in the present invention. Also, in the present invention a high resistance is added during cranking and after a predefined time the high resistance is removed. Therefore the pinion movement and contact closure have an independent operation, and the in rush current is reduced.
[0034] The present invention comprises of a plurality of solenoids, wherein one solenoid comprises of pinion movement arrangement, and another solenoid comprises of contact closure and inrush current reduction arrangement.
[0035] Figure 1 shows a cross sectional view of the contact closure and inrush current reduction solenoid (100), according to one embodiment of the invention. The contact closure and inrush current reduction solenoid comprises of an outer sleeve (112), wherein the outer sleeve (112) is rigidly fixed to the starter motor frame adjacent to the pinion movement solenoid (200). A first electromagnetic coil (111) is placed in a first bobbin (113), wherein the first bobbin (113) is arranged in axial direction to the outer sleeve (112). A first core plate (103) is placed after the first bobbin (113) and a second core plate (109) is arranged after the second bobbin (114) in axial direction. The first plunger (102) is arranged in an inner circumference of the first electromagnetic coil (111) which moves in axial direction towards the first core plate (103).
[0036] Further, a nonmagnetic material spindle (107) is connected to one end of the second plunger (104). The nonmagnetic material spindle (107) is integrally connected to the second plunger (104), wherein the spindle (107) carries two moving contact plates (105a and 105 b), which are arranged at an offset distance. The terminal base (106) containing plurality of sets of fixed contact terminals are arranged rigidly to the outer sleeve in axial direction. In the first set of two terminals, one terminal is connected to battery terminal and another terminal is interconnected to a third terminal of the second set and in the second set of two terminals, one terminal is connected to starter motor and another terminal is interconnected with the terminal of the first set of terminals via a high resistance.
[0037] A single winding coil is used for pinion movement operation and contact closure operation.
[0038] The high resistance is added during cranking and after a predefined time the high resistance is removed, wherein the high resistance is added and removed using the second plunger (104), wherein said high resistance reduces inrush current during the cranking process.
[0039] Figure 2 shows a cross sectional view of the pinion movement solenoid (200), according to one embodiment of the invention. The pinion movement solenoid (200) comprises an outer sleeve (207), wherein the outer sleeve (207) is rigidly fixed to a starter motor frame (601). The outer sleeve (207) closed at one end forms a core plate (204). An electromagnetic coil (201) is arranged in a bobbin (206), wherein the bobbin (206) is arranged in axial direction to the outer sleeve (207) at one end. The non-magnetic plate (205) is fixed at the other end of the outer sleeve (207) in axial direction, and a plunger (202) is arranged in an inner circumference of the electromagnetic coil (201) which moves in axial direction towards the core plate (204). The shift lever (701) is connected to the plunger at one end through an operating rod (203) and another connected to the pinion (702) as shown in FIGURE 7.
[0040] The plunger (202) engages with the operating rod (203), wherein the operating rod (203) is connected to the shift lever (701). The operating rod (203) is engaged with the plunger (202) through an engagement spring. The top end of the shift lever (701) is pivoted at the top of the starter motor frame (601), wherein the operating rod (203) is connected to the shift lever (701) at a smaller distance from the pivot and the bottom end of the shift lever (701) is connected to the pinion (702) which is at a larger distance from the pivot. This arrangement of the shift lever (701) enables the shift lever (701) to accelerate at a great speed and increases the speed of the pinion movement.
[0041] The shift lever arrangement accelerates pinion movement at a fast rate and the plungers move away from the non-magnetic plate (205). The shift lever ratio is higher because of pivoting the lever at the top, the plunger air gap required for pinion movement is small. The pinion movement and contact assembly have independent operations.
[0042] Figure 3 shows a cross sectional view of the terminal base assembly (106), according to one embodiment of the invention. The terminal base assembly (106) carries a plurality of sets of fixed contact terminals, which are fixed rigidly to the outer sleeve (112) of the contact closure and inrush current reduction solenoid (100) in axial direction.
[0043] The first set of terminals comprises plurality of terminals, wherein one terminal (304) is connected to a battery and other terminal (302) is interconnected to a third terminal (303) which is present in the second set of terminals. The second set of terminals comprises of, one or more terminals, wherein one terminal (301) is connected to starter motor and other terminal (303) is interconnected with a high resistance material (305) is added in between the terminal (301) and the terminal (303).
[0044] The high resistance is added during cranking and after a predefined time the high resistance is removed, wherein the high resistance is added and removed using the second plunger, wherein said high resistance reduces inrush current during the cranking process.
[0045] Figure 4 shows a circuit diagram of an electromagnetic switching apparatus for start/stop starter motor, according to one embodiment of the invention.
[0046] During cranking process the high resistance is added and after a predefined time the high resistance is removed. This is achieved by using a dual contact arrangement which adds high resistance to reduce the huge amount of inrush current during cranking process, and removes the high resistance after a predefined time, wherein the dual contact material used is cupper.
[0047] Considering the terminals T1, T2, T3 and T4 in circuit diagram as shown in the FIGURE 4. The circuit is connected to the two sets of fixed contact terminals, wherein the first set has fixed terminals T1 and T3 and second set has fixed terminals T2 and T4 as shown in the FIGURE 3. In the first set of fixed terminals (T1 and T3), the terminal T1 is connected to the battery terminal.
[0048] In the second set of fixed terminals (T2 and T4), the terminal T4 is connected to the starter motor terminal. The terminal T2 and T4 are interconnected via resistance material (305) and the terminal T3 and T4 are short circuit through a copper wire.
[0049] In the present invention, when the restart signal is obtained from Engine Control Unit (ECU), the battery terminal connects the contact closure and inrush current reduction solenoid terminal S2 and pinion movement solenoid terminal S1. In the contact closure and inrush current reduction solenoid, the first electromagnetic coil gets energized and first plunger (111) starts moving towards the first core plate (103). At the same time contact plate (105a) starts moving axially and closes the first set of fixed terminals (T1 and T3). Further the motor gets energized through the high resistance, wherein the high resistance reduces the inrush current and simultaneously the pinion movement starts operating in the pinion movement solenoid.
[0050] After a predefined time, in the contact closure and inrush current reduction solenoid, the second electromagnetic coil gets energized, wherein the predefined time is achieved by a delay circuit (D). Then, the second plunger starts moving in the axial direction and closes the second set of fixed terminal (T2 and T4). Hence the contact closure of second set of fixed terminal (T2 and T4) causes the resistor (305) to short/bypass.
[0051] Figure 5 shows a perspective view of arrangement of pinion movement solenoid, and contact closure and inrush current reduction solenoid, according to one embodiment of the invention. The outer sleeve (207) of the pinion movement solenoid (200), and the outer sleeve (112) of the contact closure and inrush current reduction solenoid (100) is firmly fixed to a starter motor frame (601), wherein the starter motor frame (601) is rigidly fixed to the engine as shown in the FIGURE 5.
[0052] Figure 6 shows a side view of arrangement of pinion movement solenoid (200), and contact closure and inrush current reduction solenoid (100), according to one embodiment of the invention. The outer sleeve (207) of the pinion movement solenoid (200), and the outer sleeve (112) of the contact closure and inrush current reduction solenoid (100) is firmly fixed to a starter motor frame (601), wherein the starter motor frame (601) is rigidly fixed to the engine as shown in the FIGURE 6. The pinion movement solenoid (200), and contact closure and inrush current reduction solenoid (100) fixed to the starter motor frame (601) are adjacent to each other.
[0053] Figure 7 shows the front view of the arrangement of pinion movement solenoid with starting motor via shift lever, according to one embodiment of the invention.
[0054] The invented electromagnetic switching apparatus uses a shift lever, wherein the top end of the shift lever is pivoted to the starter motor. Hence, the pinion movement accelerates at a fast rate. In the present invention, since the shift lever ratio is high, the plunger air gap required for pinion movement is small. Both the pinion movement and contact closure operate independently in the present invention. The present invention also uses an inrush current reduction technique, wherein the high resistance is added during cranking and after a predefined time the high resistance is removed. Hence, the high resistance material reduces inrush current during the cranking process. In the present invention, since the inrush current is reduced, the shelf life of the starter motor is increased.
[0055] It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.