BACKGROUND OF THE INVENTION
[0001] The present invention relates to an electromagnetic relay.
[0002] Heretofore, as disclosed in Japanese Patent Laid-Open Publication No.
2011-009002 (hereinafter, referred to as Patent Literature 1), an electromagnetic relay has been
known, which includes: a card that moves by driving a drive unit; movable springs
bridged by the card; movable contact points fixedly attached to one-side ends of the
movable springs; and fixed contact points arranged opposite to the movable contact
points.
[0003] In this Patent Literature 1, the card is moved by driving the drive unit, and the
movable springs are displaced by such movement of the card, whereby contact and separation
between the movable contact points and the fixed contact points are switched.
SUMMARY OF THE INVENTION
[0004] Incidentally, when a current is made to flow through the electromagnetic relay in
a state where the movable contact points and the fixed contact points are brought
into contact with each other, the movable contact points and the fixed contact points
may be fused with each other in some case. In the above-described conventional technology,
the movable springs have flexibility. Therefore, when the card is moved so that the
movable contact points and the fixed contact points can be spaced apart from each
other in the event where the movable contact points and the fixed contact points are
fused with each other at the time of being brought into contact with each other, there
is a possibility that the movable springs only warp and that it may become impossible
to space the movable contact points and the fixed contact points apart from each other.
[0005] In this connection, it is an object of the present invention to obtain an electromagnetic
relay capable of more surely spacing the movable contact points and the fixed contact
points apart from each other.
[0006] A first feature of the present invention is summarized to be an electromagnetic relay
including: a drive unit; a moving body that moves by driving the drive unit; a movable
spring attached to the moving body; a movable contact point fixedly attached to the
movable spring; and a fixed contact point arranged opposite to the movable contact
point, wherein a peeling mechanism that peels off the movable contact point and the
fixed contact point from each other in an event where the movable contact point and
the fixed contact point are fused with each other is provided on at least either one
of the moving body and the movable spring.
[0007] A second feature of the present invention is summarized in that the peeling mechanism
has a protruding portion provided on the moving body, and in an event of peeling off
the movable contact point and the fixed contact point from each other, the protruding
portion abuts against a region between a point on the movable spring where force is
applied by the moving body and the movable contact point, and presses the movable
spring in a direction that the movable contact point is spaced apart from the fixed
contact point.
[0008] A third feature of the present invention is summarized in that the peeling mechanism
has a projection portion formed between the point on the movable spring where force
is applied by the moving body and the movable contact point.
[0009] A fourth feature of the present invention is summarized in that the movable spring
has a plate shape, and the projection portion is formed by extruding the movable spring
from one surface side thereof toward the other surface side thereof.
[0010] A fifth feature of the present invention is summarized in that a region of the projection
portion which abuts against the movable body is a planar surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011]
Fig. 1 is a partially exploded perspective view of an electromagnetic relay according
to a first embodiment of the present invention.
Fig. 2 is a partially exploded perspective view of an electromagnetic relay body portion
according to the first embodiment of the present invention.
Fig. 3 is a longitudinal cross-sectional view schematically showing the electromagnetic
relay body portion according to the first embodiment of the present invention.
Fig. 4 is a plan view schematically showing the electromagnetic relay body portion
according to the first embodiment of the present invention, showing a state before
a drive unit is driven.
Fig. 5 is a plan view schematically showing the electromagnetic relay body portion
according to the first embodiment of the present invention, showing a state after
the drive unit is driven.
Fig. 6 is a partially cutaway plan view schematically showing the electromagnetic
relay body portion according to the first embodiment of the present invention, showing
the state before the drive unit is driven.
Fig. 7 is a perspective view showing a movable contact point portion according to
the first embodiment of the present invention.
Fig. 8 is a perspective view showing a moving body according to the first embodiment
of the present invention.
Fig. 9 is a front view showing the moving body according to the first embodiment of
the present invention.
Figs. 10 (a) and 10 (b) are partially enlarged plan views of an electromagnetic relay
body portion shown as a comparative example of the present invention in which Fig.
10(a) is a plan view showing a state where a movable contact point and a fixed contact
point are brought into contact with each other; and Fig. 10 (b) is a plan view showing
a state where a moving body is moved so that the movable contact point and the fixed
contact point can be separated from each other when the movable contact point and
the fixed contact point are fused with each other.
Figs. 11 (a) to 11 (c) are partially enlarged plan views of the electromagnetic relay
body portion according to the first embodiment of the present invention in which Fig.
11 (a) is a plan view showing a state where the movable contact point and a fixed
contact point are brought into contact with each other; FIG. 11 (b) is a plan view
showing a state where the moving body is moved so that the movable contact point and
the fixed contact point can be separated from each other at a normal time; and Fig.
11 (c) is a plan view showing a state where the moving body is moved so that the movable
contact point and the fixed contact point can be separated from each other when the
movable contact point and the fixed contact point are fused with each other.
Fig. 12 is a perspective view showing a movable contact point portion according to
a second embodiment of the present invention.
Figs. 13 (a) and 13 (b) are partially enlarged plan views of an electromagnetic relay
body portion according to the second embodiment of the present invention in which
Fig. 13 (a) is a plan view showing a state where the movable contact point and a fixed
contact point are brought into contact with each other; and Fig. 13 (b) is a plan
view showing a state where the moving body is moved so that the movable contact point
and the fixed contact point can be separated from each other when the movable contact
point and the fixed contact point are fused with each other.
Fig. 14 is a perspective view showing a movable contact point portion according to
a first modification example of the second embodiment of the present invention.
Fig. 15 is a perspective view showing a movable contact point portion according to
a second modification example of the second embodiment of the present invention.
Fig. 16 is a perspective view showing a movable contact point portion according to
a third modification example of the second embodiment of the present invention.
Fig. 17 is a perspective view showing a movable contact point portion according to
a fourth modification example of the second embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] A description is made below in detail of embodiments of the present invention while
referring to the drawings. Note that similar constituent elements are included in
a plurality of the following embodiments. Hence, common reference numerals are assigned
to these similar constituent elements, and a duplicate description is omitted.
(First Embodiment)
[0013] An electromagnetic relay 1 according to this embodiment is formed into a substantially
box shape in such a manner that an electromagnetic relay body portion 10 is covered
with a case 20 from the above, and that the case 20 is adhered and fixed to a body
40.
[0014] The case 20 has a substantially box shape in which a lower portion is open, and covers
an electromagnet device (drive unit) 30 and a plurality of contact point mechanisms
60, which will be described later, from the above in a state where the electromagnet
device 30 and the contact point mechanisms 60 are assembled to the body 40 (refer
to Fig. 1). In this embodiment, an outer circumferential portion 20a of the case 20
is adhered to an outer circumferential groove 43 by an adhesive, whereby the case
20 is fitted and attached to the body 40 from the outside. Note that reference numeral
23 in Fig. 1 denotes an air relief hole for preventing a rise of an inner pressure
in the case 20 in the event of adhering the case 20 to the body 40 and curing the
adhesive.
[0015] As shown in Fig. 1 and Fig. 2, the electromagnetic relay body portion 10 is formed
in such a manner that the electromagnet device (drive unit) 30 and the plurality of
contact point mechanisms 60 are assembled to the body 40.
[0016] Then, the electromagnet device (drive unit) 30 is driven by being electrically switched
on/off, and such drive of the electromagnet device (drive unit) 30 is transmitted
to a card 50, by which opened state/closed state of the plurality of contact point
mechanisms 60 can be switched.
[0017] As this electromagnet device (drive unit) 30, a publicly known one can be used. In
this embodiment, the electromagnet device 30 is composed of a core 31, a movable block
32, and a coil (not shown). The movable block 32 is moved by energizing the coil (not
shown), and following such movement of the movable block 32, the card 50 attached
to the movable block 32 is allowed to move in a longitudinal direction of the body
40.
[0018] Moreover, in the electromagnet device 30, a board-connecting terminal 30a for connecting
the electromagnet device 30 to a board (not shown) is provided. This board-connecting
terminal 30a is inserted through a terminal insertion hole (not shown) formed in a
recessed portion 44 of the body 40, which is used for mounting the electromagnet device
(drive unit) thereon. Then, the board-connecting terminal 30a is inserted through
the terminal insertion hole (not shown), and the electromagnet device 30 is press-fitted
into the body 40 so that the terminal 30a can protrude to a lower surface side of
the body 40, by which the electromagnet device 30 is assembled to a center portion
in the longitudinal direction of the body 40.
[0019] Moreover, on both end portions in the longitudinal direction of the substantially
rectangular body 40, a plurality of slit holes 41 for fixing a contact point mechanism
extended in a lateral direction thereof are formed.
[0020] Then, the outer circumferential groove 43 for adhering the body 40 to the case 20
is formed on an outer circumferential portion of the body 40. Then, the outer circumferential
portion 20a of the case 20 is fitted and adhered to this outer circumferential groove
43 from the outside, whereby the case 20 is fitted and attached to the body 40 from
the outside.
[0021] Moreover, guide recessed portions 45 extended in the longitudinal direction of the
body 40 are formed in center portions in the lateral direction of the body 40 on both
sides of a recessed portion 44 for mounting the electromagnet device (drive unit).
Then, tip ends of the card 50 are made capable of moving in the guide recessed portions
45 while being guided therein.
[0022] Furthermore, each of the plurality of contact point mechanisms 60 includes a movable
contact point portion 61 and a fixed contact point portion 62.
[0023] Each of the movable contact point portions 61 includes: a thin plate-like plate spring
(movable spring) 61a sandwiched by the card 50; and a fixed plate 61b attached to
a root portion of the plate spring 61a. Moreover, the movable contact point portion
61 includes: a board-connecting terminal 61c provided on the fixed plate 61b; and
a movable contact point 61d provided on a tip end portion of the plate spring 61a.
[0024] Meanwhile, each of the fixed contact point portions 62 includes: an upper fixed plate
62a; a lower fixed plate 62b; a board-connecting terminal 62c provided on the lower
fixed plate 62b; and a fixed contact point 62d that is provided on the upper fixed
plate 62a and is capable of being brought into contact with and separated from the
movable contact point 61d.
[0025] Then, the respective terminals 61c and 62c are inserted through the slit holes 41
so as to individually protrude to the lower surface side of the body 40, and the movable
contact point portions 61 and the fixed contact point portions 62 are press-fitted
into the slit holes 41, whereby the movable contact point portions 61 and the fixed
contact point portions 62 are assembled to the body 40.
[0026] Note that, in this embodiment, one contact point 61d and one contact point 62d are
provided on the movable contact point portion 61 and fixed contact point portion 62
of each of the contact point mechanisms 60, respectively.
[0027] Moreover, in this embodiment, among three contact point mechanisms 60 on a right
side in Fig. 4, two contact point mechanisms 60 close to the electromagnet device
(drive unit) 30 are set as normally-closed contact points. In each of the contact
point mechanisms 60 as the normally-closed contact points, the contact points 61d
and 62d are brought into contact with each other in a state where the electromagnet
device (drive unit) 30 is not excited, and when the electromagnet device (drive unit)
30 is excited, the contact points 61d and 62d are separated from each other.
[0028] Meanwhile, other contact point mechanisms 60 are set as normally-opened contact points.
In each of the contact point mechanisms 60 as the normally-opened contact points,
the contact points 61d and 62d are separated from each other in such a state where
the electromagnet device (drive unit) 30 is not excited, and when the electromagnet
device (drive unit) 30 is excited, the contact points 61d and 62d are brought into
contact with each other.
[0029] As described above, in this embodiment, in Fig. 4, from the electromagnet device
(drive unit) 30 toward a right end of the electromagnetic relay 1, the contact point
mechanism 60 as the normally-closed contact point, the contact point mechanism 60
as the normally-closed contact point, and the contact point mechanism 60 as the normally-opened
contact point are arranged in this order. On the other hand, in FIG. 4, from the electromagnet
device (drive unit) 30 toward a left end of the electromagnetic relay 1, three contact
point mechanisms 60 as the normally-opened contact points are arranged.
[0030] As described above, the electromagnetic relay 1 is made as a multipolar electromagnetic
relay, whereby one electromagnetic relay becomes usable for various circuits, and
corresponds to various purposes such as a signal-controlling electromagnetic relay
and a high current-controlling electromagnetic relay.
[0031] The card 50 includes a body portion 51 extended in the longitudinal direction of
the body 40. This body portion 51 is formed so that a center portion thereof can be
thin and that both end portions thereof can be thick. On such a thin center region
of the body portion 51, an engaging protrusion 52 to be attached to the movable block
32 is formed. Then, on such thick both end regions of the body portion 51, sandwiching
pieces 53 are formed, which are extended in the lateral direction of the body 40,
and sandwich the plate springs (movable springs) 61a of the movable contact point
portions 61.
[0032] As described above, in this embodiment, as shown in Fig. 9, the card 50 is formed
into a comb tooth shape when viewed from the front, and is made capable of sandwiching
the plurality of plate springs (movable springs) 61a. Note that protruding portions
53a are formed on the respective sandwiching pieces 53. And the plate springs (movable
springs) 61a are sandwiched by the protruding portions 53a.
[0033] Here, in this embodiment, on the card (moving body) 50, peeling mechanisms 70 are
provided, which peel off the contact points (movable contact points) 61d and the contact
points (fixed contact points) 62d from each other in the event where the contact points
(movable contact points) 61d and the contact points (fixed contact points) 62d are
fused with each other.
[0034] That is to say, the peeling mechanisms 70 are provided on at least one of the card
(moving body) 50 and the plate springs (movable springs) 61a.
[0035] Specifically, protruding portions 54 as the peeling mechanisms 70 are provided on
the card (moving body) 50. Then, in the event of spacing the contact points (movable
contact points) 61d and the contact points (fixed contact points) 62d apart from each
other, the protruding portions 54 are allowed to abut against regions between points
F on the plate springs (movable springs) 61a where force is applied by the card (moving
body) 50 and the contact points (movable contact points) 61d. That is to say, in the
event of spacing the contact points (movable contact points) 61d and the contact points
(fixed contact points) 62d apart from each other, the protruding portions 54 abut
against the regions between the points F where force is applied and the contact points
(movable contact points) 61d, and press the plate springs 61a in a direction that
the contact points (movable contact points) 61d are spaced apart from the contact
points (fixed contact points) 62d.
[0036] In this embodiment, the sandwiching pieces 53 on the contact point 62d side of the
plate springs (movable springs) 61a are extended toward the contact points 62d, whereby
the protruding portions 54 are provided on the card (moving body) 50. Here, the contact
points 62d are the fixed contact points to be brought into contact with the movable
contact points 61d provided on the plate springs 61a.
[0037] The electromagnetic relay body portion 10 is formed, for example, in such a way as
below.
[0038] First, onto both sides in the longitudinal direction of the body 40 (that is, onto
both end sides of the electromagnet device 30), the plurality (three by three in this
embodiment) of contact mechanisms 60 are assembled. At this time, the contact point
mechanisms 60 are assembled so that the plate springs (movable springs) 61a in a free
state can be arranged obliquely with respect to a direction intersecting the lateral
direction of the body 40. That is to say, in a state where the contact points (movable
contact points) 61d and the contact points (fixed contact points) 62d are brought
into contact with each other, the plate springs (movable springs) 61a are biased in
a direction of being spaced apart from the contact points (fixed contact points) 62d.
Note that cutouts 53b are provided on the sandwiching pieces 53 on an opposite side
from the fixed contact points 62d to be brought into contact with the movable contact
points 61d provided on the plate springs 61a. These cutouts 53b are provided in order
to prevent the sandwiching pieces 53 from interfering with the plate springs (movable
springs) 61a in the event of spacing the contact points (movable contact points) 61d
and the contact points (fixed contact points) 62d apart from each other.
[0039] Then, components (the core 31 and the like) of the electromagnet device 30 other
than the movable block 32 are assembled to the center portion in the longitudinal
direction of the body 40. Note that, with regard to such assembling of the contact
point mechanisms 60 and such assembling of the core 31, either may be performed first,
or both may be performed simultaneously.
[0040] Then, the plate springs (movable springs) 61a of the respective contact point mechanisms
60 are sandwiched by the card (moving body) 50, and the movable block 32 is attached
to the engaging protrusion 52 of the card (moving body) 50. Thus, the electromagnet
relay body portion 10 is formed.
[0041] Next, a description is made of operations of the electromagnetic relay 1 based on
Fig. 3 to Fig. 6.
[0042] First, in a state where the electromagnet device (drive unit) 30 is not excited,
as shown in Fig. 3, Fig. 4 and Fig. 6, the contact point mechanisms 60 as the normally-closed
contact points are in a closed state (state where the contact points 61d and 62d are
brought into contact with each other). Meanwhile, the contact point mechanisms 60
as the normally-opened contact points are in an opened state (state where the contact
points 61d and 62d are spaced apart from each other).
[0043] When the electromagnet device (drive unit) 30 is excited, the movable block 32 rotationally
moves counterclockwise in Fig. 4. Then, following such rotational movement of the
movable block 32, the card 50 attached to the movable block 32 moves to the right
side in the longitudinal direction of the body 40. As a result, the plate springs
(movable springs) 61a sandwiched by the card 50 move to the right side in the longitudinal
direction of the body 40, and the contact point mechanisms 60 as the normally-closed
contact points turn to the opened state (state where the contact points 61d and 62d
are spaced apart from each other). Meanwhile, the contact point mechanisms 60 as the
normally-opened contact points turn to the closed state (state where the contact points
61d and 62d are brought into contact with each other).
[0044] When the excitation of the electromagnet device (drive unit) 30 is released, the
movable block 32 rotationally moves clockwise in Fig. 4. Then, following such rotational
movement of the movable block 32, the card 50 attached to the movable block 32 moves
to the left side in the longitudinal direction of the body 40. As a result, the plate
springs (movable springs) 61a sandwiched by the card 50 move to the left side in the
longitudinal direction of the body 40, and the contact point mechanisms 60 as the
normally-closed contact points turn to the closed state (state where the contact points
61d and 62d are brought into contact with each other). Meanwhile, the contact point
mechanisms 60 as the normally-opened contact points turn to the opened state (state
where the contact points 61d and 62d are spaced apart from each other). At this time,
in a normal state (state where the contact points 61d and the contact points 62d are
not fused with each other), the plate springs (movable springs) 61a move from a position
as shown in Fig. 11(a) to a position as shown in Fig. 11(b). That is to say, in the
case where the contact points 61d and the contact points 62d are not fused with each
other, the contact points 61d and 62d are spaced apart from each other by resilience
of the plate springs (movable springs) 61a themselves without allowing the protruding
portions 54 to interfere with the plate springs (movable springs) 61a.
[0045] Incidentally, when a current is made to flow through the contact points (movable
contact points) 61d and the contact points (fixed contact points) 62d in a state where
the contact points 61d and the contact points 62d are brought into contact with each
other, the contact points 61d and the contact points 62d may be fused with each other
in some case. The plate springs (movable springs) 61a have flexibility. Therefore,
in the case of using a card 100 in which the peeling mechanisms are not provided,
there is a possibility that the plate springs 61a may operate so as to turn from a
state shown in Fig. 10(a) to a state shown in Fig. 10(b). Specifically, in the case
of using the card 100, in the event of moving the card 100 so that the contact points
61d and the contact points 62d can be spaced apart from each other in the state where
the contact points 61d and 62d are fused with each other, the plate springs 61a are
warped. When the plate springs 61a are warped, sufficient force is not applied to
such fused portions between the contact points 61d and 62d, and there is a possibility
that it may become impossible to space the contact points 61d and the contact points
62d apart from each other.
[0046] As described above, in the case of using the card 100, there is a possibility that
the circuit may be caused to malfunction as a result that both of the normally-opened
contact points and the normally-closed contact points turn to the closed state.
[0047] However, in this embodiment, the protruding portions 54 as the peeling mechanisms
70 are provided on the card (moving body) 50. And in the event of spacing the contact
points (movable contact points) 61d and the contact points (fixed contact points)
62d apart from each other, these protruding portions 54 are allowed to abut against
the regions between the points F on the plate springs (movable springs) 61a where
force is applied by the card (moving body) 50 and the contact points (movable contact
points) 61d. Therefore, in the case of moving the card 50 so that the contact points
61d and the contact points 62d can be spaced apart from each other in the state where
the contact points 61d and 62d are fused with each other, the protruding portions
54 are made to abut against the warped plate springs (movable springs) 61a on the
course of the movement. Then, following the movement of the card 50, the protruding
portions 54 abut against the regions between the points F where force is applied and
the contact points (movable contact points) 61d, and press the plate springs 61a in
the direction that the contact points (movable contact points) 61d are spaced apart
from the contact points (fixed contact points) 62d (refer to Fig. 11(c)). As a result,
force to be applied to the fused portions between the contact points 61d and 62d (that
is, force to separate the contact points 61d and 62d from each other) can be increased
more, and it becomes possible to space the contact points 61d and 62d, which are fused
with each other, apart from each other.
[0048] As described above, in this embodiment, on the card (moving body) 50, the protruding
portions 54 are provided, which serve as the peeling mechanisms 70 capable of peeling
off the contact points (movable contact points) 61d and the contact points (fixed
contact points) 62d from each other in the event where the contact points (movable
contact points) 61d and the contact points (fixed contact points) 62d are fused with
each other. As a result, it becomes possible for the protruding portions 54 to peel
off the contact points (movable contact points) 61d and the contact points (fixed
contact points) 62d, which are fused with each other, from each other, and the contact
points (movable contact points) 61d and the contact points (fixed contact points)
62d can be spaced apart from each other more surely.
[0049] Moreover, in this embodiment, the protruding portions 54 as the peeling mechanisms
70 are provided by making the sandwiching pieces 53 of the card (moving body) 50 to
protrude. Therefore, it becomes possible to obtain the electromagnetic relay 1 which
is capable of spacing the contact points (movable contact points) 61d and the contact
points (fixed contact points) 62d apart from each other more reliably while simplifying
its configuration.
(Second Embodiment)
[0050] An electromagnetic relay 1 according to this embodiment basically has a similar configuration
to that of the electromagnetic relay 1 according to the above-described first embodiment.
That is to say, the electromagnetic relay 1 according to this embodiment also is formed
into a substantially box shape in such a manner that an electromagnetic relay body
portion 10 is covered with a case 20 from the above, and that the case 20 is adhered
and fixed to a body 40.
[0051] And on a card (moving body) 50, protruding portions 54 as peeling mechanisms 70 are
provided.
[0052] Here, the electromagnetic relay body portion 10 of this embodiment is mainly different
from that of the first embodiment in that the peeling mechanisms 70 have projection
portions 61e, each of which is formed between a point F on a plate spring (movable
spring) 61a where force is applied by the card (moving body) 50 and a contact point
(movable contact point) 61d.
[0053] In this embodiment, the plate spring (movable spring) 61a has a plate shape, and
the projection portion 61e is formed into an elongated quadrangular truncated pyramidal
shape in a longitudinal direction of a movable contact point portion 61 (that is,
a lateral direction of the body 40).
[0054] Moreover, in this embodiment, the projection portion 61e is formed in such a manner
that the plate spring (movable spring) 61a is extruded from one surface side thereof
(opposite side from a fixed contact point 62d to be brought into contact with the
movable contact point 61d provided on the plate spring 61a concerned) toward the other
surface side (fixed contact point 62d side) thereof.
[0055] And a planar surface 61f is formed on a region of the projection portion 61e which
abuts against the card (moving body) 50.
[0056] Also in accordance with this embodiment described above, functions and effects similar
to those of the above-described first embodiment can be achieved.
[0057] Moreover, in accordance with this embodiment, each of the peeling mechanisms 70 has
the projection portion 61e formed between the point F on the plate spring (movable
spring) 61a where force is applied by the card (moving body) 50 and the contact point
(movable contact point) 61d. Therefore, in the event of moving the card (moving body)
50 in a state where the contact point (movable contact point) 61d and the contact
point (fixed contact point) 62d are fused with each other, the plate spring (movable
spring) 61a can be suppressed from being warped. As a result, force to be applied
to such a fused portion between the contact points 61d and 62d can be increased, and
it becomes possible to peel off the contact point (movable contact point) 61d and
the contact point (fixed contact point) 62d which are fused with each other, apart
from each other more reliably.
[0058] Note that, in a normal state (state where the contact point 61d and the contact point
62d are not fused with each other), the plate spring (movable spring) 61a moves from
a position as shown in Fig. 11 (a) to a position as shown in Fig. 11 (b) in a way
similar to the above-described first embodiment.
[0059] Moreover, in accordance with this embodiment, the projection portion 61e is formed
in such a manner that the plate spring (movable spring) 61a is extruded from one surface
side thereof (opposite side from the fixed contact point 62d to be brought into contact
with the movable contact point 61d provided on the plate spring 61a) toward the other
surface side (fixed contact point 62d side) thereof. Therefore, in comparison with
the case where the projection portion 61e is formed by being bent, it becomes easy
to stably obtain accuracy of its height, and its operation characteristics can be
stabilized. Moreover, there is also an advantage that there is reduced friction and
abrasion in the case where the projection portion 61e is brought into contact with
the card when the contact point 61d and the contact point 62d are slightly fused with
each other. Moreover, since the number of assembly steps of the projection point 61e
is small in comparison with the case where the projection portion 61e is formed by
adhesion, cost reduction can be achieved. Furthermore, the projection portion 61e
can be suppressed from slipping off as in the case where the projection portion 61e
is formed by the adhesion.
[0060] Furthermore, in accordance with this embodiment, the planar surface 61f is formed
on the region of the projection portion 61e, which abuts against the card (moving
body) 50. Therefore, the warp of the spring is less likely to occur even for three-dimensional
deformation of the spring, such as a twist, and it becomes possible to peel off the
contact point (movable contact point) 61d and the contact point (fixed contact point)
62d that are fused with each other more reliably from each other.
[0061] Incidentally, in this embodiment, as the projection portion, the quadrangular truncated
pyramidal projection portion 61e is illustrated, which is formed by extruding the
plate spring (movable spring) 61a from one surface side thereof to the other surface
side thereof; however, the shape of the projection portion can be formed into various
shapes without being limited to this shape.
[0062] For example, as shown in Fig. 14, as the projection portion, a semicircular columnar
projection portion 61e may be adopted, which is formed by extruding the plate spring
(movable spring) 61a from one surface side thereof to the other surface side thereof.
[0063] Moreover, as shown in Fig. 15, as the projection portion, a triangular prism projection
portion 61e may be adopted, which is formed by extruding the plate spring (movable
spring) 61a from one surface side thereof to the other surface side thereof.
[0064] Moreover, as shown in Fig. 16, a plurality (two in Fig. 16) of projection portions
61e may be formed by extruding the plate spring (movable spring) 61a from one surface
side thereof to the other surface side thereof.
[0065] Moreover, as shown in Fig. 17, the projection portion 61e may be formed by adhering
a quadrangular truncated pyramidal member as another member to the other surface side
of the plate spring (movable spring) 61a. Note that it is possible to appropriately
set a shape and number of such another member.
[0066] With the projection portions 61e as described above, substantially similar functions
and effects to those of the above-described second embodiment can be achieved.
[0067] The description has been made above of the preferred embodiments of the present invention;
however, the present invention is not limited to the above-described embodiments,
and is modifiable in various ways.
[0068] For example, in each of the above-described embodiments, the electromagnetic relay
has been illustrated in which the plurality of contact point mechanisms are arranged
on both sides of the drive unit; however, the plurality of contact point mechanisms
may be arranged on one side of the drive unit.
[0069] Moreover, in the above-described first embodiment, the electromagnetic relay has
been illustrated in which the projection portions as the peeling mechanisms are provided
on the card, and in the above-described second embodiment, the electromagnetic relay
has been illustrated in which the protruding portions as the peeling mechanisms are
provided on the card and the projection portions as the peeling mechanisms are formed
on the plate springs. However, the projection portions as the peeling mechanisms may
be formed on the plate springs without providing the protruding portions as the peeling
mechanisms on the card.
[0070] Moreover, it is also possible to appropriately change specifications (shapes, sizes,
layout and the like) of the movable springs, the contact points and other details.