DESCRIPTION TITLE OF INVENTION ROCKER SWITCH
TECHNICAL FIELD
[0001] The invention relates to a rocker switch, which includes a handle configured to be manipulated in two (opposite) directions and which is configured to be switched between ON and OFF in response to the respective directional manipulations of the handle.
BACKGROUND ART
[0002] Japanese Patent Application Publication No. 52-009878 discloses a rocker switch including: a housing! a handle for switching between ON and OFF of the switch; a movable frame disposed so as to be swingable between an ON position and an OFF position; and an inversion spring disposed between the handle and the movable frame. The movable frame is formed in a substantially U-shape. The movable frame is disposed in the housing so that an open end of the movable frame faces the handle and the movable frame can turn over (rock; swing) around a closed end thereof. The movable I frame has electric conductivity, and is provided with a movable contact. A stationary terminal provided with a stationary contact is disposed in the housing. One end of the inversion spring is fixed to a bottom of a recess formed in the handle, and the other end of the inversion spring is inserted and fixed in the U-shaped movable frame. The expansion/contraction

direction of the inversion spring is substantially perpendicular to an operation face (top face) of the handle. The handle is held stably under the spring force of the inversion spring. In this switch, when the handle is manipulated to be turned over (swinging operation), the movable frame and the inversion spring together turn over in response to the manipulation (swinging operation) of the handle. Thus, the contacts are switched between a closed state (in which the movable contact is in contact with the stationary contact) and an opened state (in which the movable contact is apart from the stationary contact) in response to the swinging operation of the handle.
[0003] In the conventional rocker switch, because the movable frame is subjected to stress by the expansion/contraction of the inversion spring when the handle is being turned over, there is a concern that the movable frame, which is swingably attached to the housing, may be deformed (and be displaced in position in the housing) due to repetitive operation of the handle. If the movable frame is deformed, the accuracy of closing and opening of the contacts may be deteriorated.
DISCLOSURE OF INVENTION
[0004] The invention is developed in view of the above problem, and it is an object of the present invention to avoid deformation of a component of the rocker switch caused by the spring force.
[0005] A rocker switch of the invention includes^ a housing having an opening, the opened direction of the opening defining upward,' a first

terminal and a second terminal which are disposed in the housing and
configured to be connected with an external circuit; a stationary contact
disposed in the housing and electrically connected with the first terminal; a
movable contact plate having an electric conductivity, the movable contact
plate being supported so as to be swingable between an ON position and an
OFF position with respect to the housing, a length direction of the movable
contact plate defining a front-rear direction; a handle attached to the
movable contact plate so as to be swingable together with the movable
contact plate with respect to the housing, the handle having an operation
face exposed from the opening of the housing, the; a movable contact
connected to the movable contact plate so as to be made in contact with the
stationary contact when the movable contact plate is positioned at the ON
position? a support member electrically connecting the movable contact plate
and the second terminal therethrough; an inversion spring provided tensely
between the movable contact plate and the support member! and a base
supporting the support member to fix the position of the support member in
the housing. The movable contact plate is shaped like a plate having a front
part and a rear part in the length direction, the movable contact plate being
provided at the front part thereof with the movable contact, the movable
contact plate being provided at the rear part thereof with a first hook on
which one end of the inversion spring is put. The support member has a
second hook on which the other end of the inversion spring is put. The
support member has a pivot support portion for pivotally supporting an
intermediate part in the length direction of the movable contact plate,

thereby supporting the movable contact plate swingably around the pivot
support portion as a fulcrum between the ON position in which the movable
contact makes in contact with the stationary contact and the OFF position in
which the movable contact is away from the stationary contact. The
inversion spring is provided between the first hook and the second hook in a
tensioned state to apply the spring force so that the movable contact plate is
held stable in the ON position and the OFF position, respectively. The
support member includes a support body and a clip body, the support body
being formed in a substantially U-shape having a front piece and a pair of
side pieces extending rearward from respective lateral sides of the front piece,
the support body being attached to the base by means of the clip body. The
second hook is formed at an upper end of the front piece, and the pivot
support portion is formed at upper parts of the side pieces. The clip body
includes^ a support piece extending rearward from a lower end of the front
piece of the support body; a leg piece extending downward from one side of
the support piece! and an attachment piece extending from a lower end of the
leg piece so as to face the support piece. A part of the second terminal and
the base are inserted between the support piece and the attachment piece,
whereby the support member is fixed to the base. Lower ends of the side
pieces of the support body are supported by a top face of the support piece of
the clip body.
[0006] In one embodiment, the movable contact plate has an elongated hole elongated in the front-rear direction at a center of the movable contact plate. The elongated hole has a widened portion formed at front side and a

narrowed portion formed at rear side which are formed continuously via a step part. The step part has an edge at the tip, which defines a fulcrum for swingably supporting the movable contact plate. The step part has a thickness gradually thinned toward the tip of the step part. [0007] In one embodiment, the second terminal includes a terminal frame having an upper piece, a bottom piece and a pair of side pieces. The housing has a terminal hole in which the terminal frame is disposed. The base has a thinned-bottom part to define a storing recess in which the support member is fitted. The thinned-bottom part of the storing recess and the upper piece of the terminal frame are held between the support piece and the attachment piece while the upper piece of the terminal frame is in contact with a lower surface of the thinned-bottom part of the storing recess.
[0008] In one embodiment, the inversion spring is disposed so that expansion/contraction direction is substantially in parallel with the length direction of the movable contact plate.
[0009] In one embodiment, the movable contact plate has an elongated hole elongated in the front-rear direction at a center of the movable contact plate. The inversion spring is disposed inside the elongated hole.
BRIEF DESCRIPTION OF DRAWINGS
[0010] Preferred embodiments of the invention will now be described in further details. Other features and advantages of the present invention will become better understood with regard to the following detailed description and accompanying drawings where:

FIG. 1 is a perspective view of a rocker switch according to an embodiment;
FIG. 2 is an exploded perspective view of the rocker switch according to the embodiment;'
FIG. 3A is a perspective view of a support member, a movable contact plate and an inversion spring of the rocker switch according to the embodiment, and FIG. 3B is a perspective vie of the support member, the movable contact plate and the inversion spring which are assembled together;
FIG. 4 is a sectional view of the rocker switch according to the embodiment;
FIG. 5A is a sectional view of the rocker switch according to the embodiment in an ON state, and FIG. 5B is a sectional view of the rocker switch according to the embodiment in an OFF state,"
FIG. 6A is a front view of the support member of the rocker switch according to the embodiment, and FIG. 6B is a side view of the support member of the rocker switch according to the embodiment; and
FIG. 7A is a plan view of the movable contact plate of the rocker switch according to the embodiment, and FIG. 7B is a sectional view of the movable contact plate taken along the line A-A in FIG. 7A.
DESCRIPTION OF EMBODIMENTS
[0011] It will be described a rocker switch 100 according to an embodiment of the invention with reference to FIGS. 1 to 7. In the following description,

components of the switch 100 are described as that the left end in FIG. 1 of the switch 100 corresponds to "front". That is, the rocker switch 100 includes: a housing 20 having an opening; and a movable contact plate 70 supported so as to be swingable between an ON position and an OFF position with respect to the housing 20. The opened direction of the opening of the housing 20 determines "upward". The length direction of the movable contact plate 70 determines a front-rear direction.
[0012] The rocker switch 100 includes: the housing 20 designed to be
installed in a wall or the like! and a handle 10 swingably disposed with
respect to the housing 20 between an ON position and an OFF position. As
shown in FIG. 2, a first terminal 30, a second terminal 35 and a stationary
contact 31 are disposed in the housing 20. The first terminal 30 and the
second terminal 35 are configured to be connected to an external circuit.
The stationary contact 31 is electrically connected with the first terminal 30.
The movable contact plate 70 is disposed inside the handle 10 and is
supported so as to be swingable between the ON position and the OFF
position with respect to the housing 20. A movable contact 71 is provided on
a front part of the movable contact plate 70 such that the movable contact 71
is made in contact with the stationary contact 31 when the movable contact
plate 70 is positioned at the ON position. A support member 50 is disposed
in the housing 20. The movable contact plate 70 is swingably supported by
the support member 50. The support member 50 electrically connects the
movable contact plate 70 and the second terminal 35 therethrough (i.e., the
movable contact plate 70 and the second terminal 35 are electrically

connected through the support member 50). The support member 50 is held by a base 40 which is fixed to the housing 20. The support member 50 and the movable contact plate 70 are connected by an inversion spring 80 such that the movable contact plate 70 is held stably in each of the ON position and the OFF position under the spring force of the inversion spring 80. In the ON position, as shown in FIG. 5A, the movable contact 71 is in contact with the stationary contact 31, so that the first terminal 30 and the second terminal 35 are electrically connected through the movable contact plate 70. In the OFF position, as shown in FIG. 5B, the movable contact 71 is apart from the stationary contact 31, so that electrical connection between the first terminal 30 and the second terminal 35 is broken.
[0013] The housing 20 is made of synthetic resin, and has storage space 21 in which the support member 50, the handle 10 and the like are put. The storage space 21 is formed continuously with the above-mentioned opening formed at the top face of the housing 20. As shown in FIGS. 5A, 5B, the housing 20 has terminal holes (22, 23) each of which is opened downward and also is communicated with the storage space 21. The first terminal 30 is disposed in the terminal hole 22, and the second terminal 35 is disposed in the terminal hole 23. As shown in FIG. 2, the housing 20 has wiring holes 24 each of which is opened on the lateral side of the housing 20 and is communicated with the terminal hole (22 or 23). An external wire can be inserted in the terminal hole (22 or 23) through a wiring hole 24. [0014] As shown in FIG. 2, each of the first terminal 30 and the second terminal 35 is formed in a rectangular (closed-)frame shape having openings

on both lateral sides thereof. The first terminal 30 and the second terminal
35 are disposed in the terminal holes (22, 23), respectively so that the
openings of the terminals (30, 35) face to be communicated with the wiring
holes 24 (note that, the housing 20 has wiring holes 24 on both the lateral
sides). The stationary contact 31 is provided on a top face of the first
terminal 30. Each of the first terminal 30 and the second terminal 35 has a
screw hole 33 which is formed at a lower side of the terminal and configured
to be screwed with a terminal screw 32. External wires are inserted inside
the terminals (30, 35) through the wiring holes 24 of the housing 20, and are
electrically connected with the first terminal 30 and the second terminal 35,
respectively by screwing the respective terminal screws 32.
[0015] As shown in FIGS. 5A, 5B, the handle 10 is made of synthetic resin,
and is formed in a box-shape with an opening which is opened downward to
form a recess 11. The handle 10 has, on the top side, an operation face 101
exposed from the housing 20. The movable contact plate 70 and the
inversion spring 80 are put inside the recess 11 formed on the lower side
(reverse side) of the handle 10. The movable contact plate 70 has an electric
conductivity. The movable contact plate 70 is formed in an elongated shape
having a front part and a rear part (see FIG. 5A, 5B). A hole 72 is formed at
the front part of the movable contact plate 70. The movable contact 71 is
fixed to the hole 72. A hole 73 is formed at the rear part of the movable
contact plate 70. A screw 13 is inserted in the hole 73 and is screwed with a
screw hole 12 formed in the handle 10, whereby the movable contact plate 70
is fixed to the handle 10.

[0016] As shown in FIGS. 3A, 3B, an elongated hole 74 elongated in the
front-rear direction is formed at a center of the movable contact plate 70.
The elongated hole 74 has a widened portion 77 formed at front side and a
narrowed portion 78 formed at rear side which are continued via a step part
76. The widened portion 77 has a wider width in comparison with the
narrowed portion 78, in a direction perpendicular to the length direction of
the movable contact plate 70. The step part 76 has an edge at a tip thereof.
A fulcrum for swingably supporting the movable contact plate 70 is defined
by the edge of the step part 76 together with a pivot support portion 56 of the
support member 50. As shown in FIG. 7, the step part 76 has a tapered
shape in which the thickness of the step part 76 gradually thinned toward
the tip. The movable contact plate 70 is swingably supported by the pivot
support portion 56 while either upper face or lower face of the edge slidingly
engages with a curved surface of the pivot support portion 56. Because the
tip part of the step part 76 has a tapered shape, it is possible to reduce the
friction caused at a contacting point between the movable contact plate 70
and the support member 50. Because the friction can be reduced, it is
possible to suppress occurrence of such a failure that the handle is stopped at
an intermediate position, and therefore the switch can has a longer life.
The movable contact plate 70 further has a first hook 75. The first hook 75
is formed to extend upward from a rear end of the narrowed portion 78. A
rear end (first end) of the inversion spring 80 is put (hooked) on the first hook
75.
[0017] As shown in FIG. 3A, the support member 50 includes- a support

body 50A for supporting the movable contact plate 70; and a clip body 50B
for attaching therethrough the support body 50A to the base 40. The
support body 50A is formed in a substantially U-shape having: a front piece
51; and a pair of side pieces 52 extending rearward from respective lateral
ends (sides) of the front piece 51. A second hook 55 is formed at an upper
end of the front piece 51. A front end (second end) of the inversion spring 80
is put (hooked) on the second hook 55. Protrusions 53 are formed on a front
face of the front piece 51 so that the support member 50 is accurately
positioned with respect to the base 40 by the protrusions 53 coming in
contact with a front wall of the base 40. Substantially V-shaped recesses
are formed at upper parts of the side pieces 52. The V-shaped recess is
engaged with the step part 76 (i.e., engaged with the edge serving as the
fulcrum). That is, the V-shaped recess defines (serves as) the pivot support
portion 56 configured to be engaged with the edge of the movable contact
plate 70. With this configuration, the movable contact plate 70 can be
swingably supported between the ON position and the OFF position around
the fulcrum, where the movable contact 71 makes in contact with the
stationary contact 31 at the ON position, and the movable contact 71 is apart
from the stationary contact 31 at the OFF position.
[0018] The clip body 50B includes: a support piece 57 extending rearward from a lower end of the front piece 51 of the support body 50A,' a leg piece 58 extending downward from a lateral end (side) of the support piece 57; and an attachment piece 59 extending from a lower end of the leg piece 58 so as to face the support piece 57. A recess 41 is formed on an upper face of the base

40. The attachment piece 59 is inserted below a bottom part
(thinned/bottom part) of the recess 41. The support member 50 is fixed to
the base 40 by holding the bottom part of the recess 41 and a part of the
second terminal 35 between the support piece 57 and the attachment piece
59. The attachment piece 59 is connected to the second terminal 35, so that
the second terminal 35 is electrically connected to the movable contact 71 of
the movable contact plate 70 through the support member 50. As shown in
FIGS. 5A, 5B, in the support member 50, (lower ends of) the side pieces 52,
52 included in the support body 50A are, in contact with the support piece 57
(which is disposed on the upper face of the bottom part of the recess 41) or
face the support piece 57 with leaving little clearance therebetween. With
this configuration, the pair of the side pieces 52 can prevent the front piece
51 from being inclined rearward caused by the tensile stress of the inversion
spring 80, and therefore can prevent a rearward displacement of the pivot
support portion 56 formed at the upper parts of the side pieces 52. As a
result, it is possible to keep the fulcrum for supporting the movable contact
plate 70 at a fixed position, and to provide a stable contact operation.
[0019] As shown in FIGS. 2, 4, the base 40 has latch nails 42 which are
formed at front and rear ends on respective lateral sides of the base 40. As
shown in FIG. 4, the housing 20 has latch holes 26 which are formed at
lateral walls of the storage space 21. The base 40 can be fixed to the
housing 20 by engaging the latch nails 42 with the respective latch holes 26.
As shown in FIG. 2, the upper face of the base 40 has inclined surfaces at
positions front and rear of the recess 41. Accordingly, it is possible to

arrange the base 40 near the handle 10 and to make the switch thinner, in addition to avoid occurrence of a collision between the base 40 and the movable contact plate 70 while the movable contact plate 70 can swing (turn over) between the ON position and the OFF position. In addition, recesses (grooves) 43 are formed on front and rear ends of the base 40. Accordingly, as shown in FIG. 5B, it is possible to avoid the base 40 from coming in contact with a head of the screw 13 (with which the movable contact plate 70 is fixed to the handle 10).
[0020] As shown in FIG. 3B, the rear and the front ends of the inversion spring 80 are put on the first hook 75 of the movable contact plate 70 and the second hook 55 of the support member 50, respectively, so that the inversion spring 80 provides the spring force to the movable contact plate 70 and the support member 50 so that the movable contact plate 70 is held stably at each of the ON and OFF positions. Accordingly, the handle 10 is rocked between the ON position and the OFF position against the spring force of the inversion spring 80. In case of switching the position of the handle 10 between the ON position and the OFF position, the movable contact plate 70 (and the handle 10) is applied with an inversed spring force that urges the handle 10 and the movable contact plate 70 into the ON position or the OFF position when the handle 10 moves across a neutral point. And then, the handle 10 and the movable contact plate 70 attached thereto are held stably in each of the ON position (see FIG. 5A) and the OFF position (see FIG. 5B) by the spring force. As shown in FIG. 3B, the inversion spring 80 is disposed inside the elongated hole 74 so that expansion/contraction direction

of the inversion spring 80 is substantially in parallel with the length direction (front-rear direction) of the movable contact plate 70. [0021] It is notable that, in case of switching the handle 10 between the ON position and the OFF position, the spring force generated by the expansion and contraction of the inversion spring 80 acts not only on the first hook 75 but on the second hook 55. Because the second hook 55 is formed at the upper end of the front piece 51 of the support member 50, the second hook 55 is applied with the force from the inversion spring 80 to cause the front piece
51 to be deformed rearward. However, in the embodiment, the side pieces
52 are formed to extend rearward from the lateral ends of the front piece 51, and the side pieces 52 are supported by the support piece 57 which extends rearward from the lower end of the front piece 51. With this configuration, it is possible to suppress the deformation of the front piece 51 (deformation of the support body 50A), and to keep the fulcrum defined in the support body 50A in a fixed position. That is, in the embodiment, the deformation of the support body 50A caused by the spring force of the inversion spring 80 can be prevented by the support piece 57, where the support piece 57 is included in the clip body 50B and designed for attaching the support member 50 to the housing 20 through the base 40. As a result, the embodiment can provide a stable contact operation for a long time.
[0022] As shown in FIGS. 5A, 5B, the support member 50 and the second terminal 35 are fixed together to the base 40 by the clip body 50B of the support member 50, and thereby the second terminal 35 is electrically connected to the movable contact plate 70 through the support member 50.

An upper piece in the rectangular frame-shaped second terminal 35 is made
in contact with a lower face of the base 40, specifically with a lower face of
the bottom part of the recess 41. The second terminal 35 is fixed to the base
40 by holding the bottom part of the recess 41 and the upper piece of the
second terminal 35 between the attachment piece 59 and the support piece
57 of the clip body 50B. Therefore, the base 40 and the second terminal 35
are housed in the housing 20 in an assembled state. On the other hand, the
stationary contact 31 is fixed to the first terminal 30 with a fixing plate 36
which is located below an upper piece of the first terminal 30. The first
terminal 30 and the stationary contact 31 are housed in the housing 20 in an
assembled state. The first terminal 30 and the second terminal 35 are put
inside the terminal holes (22, 23) along with the respective terminal screws
32. Note that, a stopper 25 is formed at a lower part of each terminal hole
(22, 23) (see FIG. 5A, 5B). Accordingly, the terminal screw 32 is prevented
from being fallen outside the housing 20 by the stopper 25.
[0023] Although the present invention has been described with reference to
certain preferred embodiments, numerous modifications and variations can
be made by those skilled in the art without departing from the true spirit
and scope of this invention, namely claims.
INDUSTRIAL APPLICABILITY
[0024] The present invention can prevent the components in the housing from being deformed and/or displaced due to the spring force of the inversion spring.

CLAIMS 1. A rocker switch comprising:
a housing having an opening, the opened direction of the opening defining upward;
a first terminal and a second terminal which are disposed in the housing and configured to be connected with an external circuit;
a stationary contact disposed in the housing and electrically connected with the first terminal;
a movable contact plate having an electric conductivity and a length, the movable contact plate being supported so as to be swingable between an ON position and an OFF position with respect to the housing, the length direction of the movable contact plate defining a front-rear direction;
a handle attached to the movable contact plate and configured to be swingable together with the movable contact plate with respect to the housing, the handle having an operation face exposed from the opening of the housing;
a movable contact connected to the movable contact plate so as to be made in contact with the stationary contact when the movable contact plate is positioned at the ON position,"
a support member electrically connecting the movable contact plate and the second terminal therethrough;
an inversion spring provided tensely between the movable contact plate and the support member; and
a base supporting to fix the support member in the housing,

wherein the movable contact plate is shaped like a plate having a front part and a rear part, the movable contact plate being provided at the front part thereof with the movable contact, the movable contact plate being provided at the rear part thereof with a first hook on which one end of the inversion spring is put,
the support member has a second hook on which the other end of the inversion spring is put,
the support member has a pivot support portion for pivotally supporting an intermediate part in the length direction of the movable contact plate, thereby supporting the movable contact plate swingably around the pivot support portion as a fulcrum between the ON position in which the movable contact is in contact with the stationary contact and the OFF position in which the movable contact is away from the stationary contact, and
the inversion spring is provided between the first hook and the second hook in a tensioned state to apply the spring force so that the movable contact plate is held stable in the ON position and the OFF position,
wherein the support member includes a support body and a clip body, the support body being formed in a substantially U-shape having a front piece and a pair of side pieces extending rearward from respective lateral sides of the front piece, the support body being attached to the base by means of the clip body,
the second hook is formed at an upper end of the front piece, and the pivot support portion is formed at an upper part of the side piece,

wherein the clip body includes^ a support piece extending rearward from a lower end of the front piece of the support body! a leg piece extending downward from one side of the support piece! and an attachment piece extending from a lower end of the leg piece so as to face the support piece, and
a part of the second terminal and the base are inserted between the support piece and the attachment piece, whereby the support member is fixed to the base,
wherein lower ends of the side pieces of the support body are supported by a top face of the support piece of the clip body.
2. The rocker switch according to claim 1, wherein
the movable contact plate has an elongated hole elongated in the front-rear direction at a center of the movable contact plate,
the elongated hole has a widened portion formed at front side and a narrowed portion formed at rear side which are formed continuously via a step part, the step part having an edge at the tip, which defines a fulcrum for swingably supporting the movable contact plate, and
the step part has a thickness gradually thinned toward the tip of the step part.
3. The rocker switch according to claim 1 or 2, wherein
the second terminal includes a terminal frame having an upper piece, a bottom piece and a pair of side pieces,

the housing has a terminal hole in which the terminal frame is disposed,
the base has a thinned-bottom part to define a recess in which the support member is fitted, and
the thinned-bottom part of the recess and the upper piece of the terminal frame are held between the support piece and the attachment piece while the upper piece of the terminal frame is in contact with a lower face of the thinned-bottom part of the recess.
4. The rocker switch according to any one of claims 1 to 3, wherein
the inversion spring is disposed so that expansion/contraction direction is substantially in parallel with the length direction of the movable contact plate.
5. The rocker switch according to claim 4, wherein
the movable contact plate has an elongated hole elongated in the front-rear direction at a center of the movable contact plate, and the inversion spring is disposed inside the elongated hole.