JPH078918U - Leaf switch - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to obtain a highly accurate leaf switch by securely attaching the fixed piece and the movable piece to the housing. A supporting wall parallel to the side wall is provided in the housing, a projecting portion that abuts at the other end of the fixing piece is provided, and one end side of the fixing piece is supported by the side wall in a direction intersecting the longitudinal direction. A convex portion that fits into the fitting groove formed between the wall and the wall is provided. [Effect] There is an advantage that a leaf switch with extremely high operation accuracy can be obtained.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to a leaf switch operated by a plunger.

[0002]

[Conventional switch and its problems]

 Conventionally, this type of switch is provided with a movable piece 26 having a movable contact point 34 between a pair of fixed contacts 33 and 53, as shown in FIG. The first fixed contact 33 is pressed against the elasticity and has the fixed contact 53 on the other side, or the first fixed contact 33 and the second fixed contact 53 have the first fixed contact 53 between them as shown in FIG. A first movable piece 26 having a contact 34 that is in constant contact with the fixed contact 33 of the second movable piece 46, and a second movable piece 46 having a contact 54 that is open with respect to the second fixed contact 53. A plunger 61 is engaged with the free end of the movable piece so as to maintain both movable pieces at a predetermined distance, and by operating this plunger, the movable contacts 34 and 54 are respectively fixed to the first position. Pair the contact 33 and the second fixed contact 53 There are those that open and close.

However, since the movable contacts 34, 54 are attached by caulking to the free ends of the movable pieces 26, 46 formed by a single strip, the movable contacts 34, 54 of the movable pieces 26, 46 cannot be separated. The portion from the attachment point to its free end is not collinear with the portion from the movable contact 34, 54 to the start point of the movable piece 26, 46, that is, at different angles for each movable piece. have. In other words, the portions of the movable pieces 26, 46 on the free end side of the movable contacts 26, 46 are inclined toward or away from the fixed contacts 33, 53 to be paired. Therefore, when the plunger 61 is in direct contact with the movable pieces 26 and 46, the contact pressures of the movable contacts 34 and 54 with respect to the fixed contacts 33 and 53 vary, and in particular, they are located on the upper side in FIG. In the case of the movable contact 34, which is always pressed in the closing direction by the switching element 41, that is, the plunger 61, the accuracy is lowered. Further, in the case of the normally open type such as the switching element 51 located on the lower side of FIG. 10, the movable piece 46 is pressed by the plunger 61, and the second movable contact 54 with respect to the second fixed contact 53. If the plunger 61 is further pressed in the state of being in contact with the movable piece 46, stress may be applied to a portion of the movable piece 46 in contact with the movable contact 54 and a supporting point of the movable piece 46, and the movable piece 46 may be broken. In order to prevent this, it is necessary to reduce the amount of movement of the plunger 61, but not only it becomes a switch that is difficult to use in operation, but also it is necessary to reduce the gap between the movable contact 54 and the fixed contact 53 so that insulation is not achieved. Since the performance deteriorates, the operating position is inaccurate, and the displacement of the movable piece 46 is naturally limited, the switch operation, especially the movement after the closing operation, that is, the overtravel cannot be sufficiently obtained, and the desired contact is obtained. There is a drawback that pressure cannot be obtained.

In general, a cantilever beam-shaped movable piece needs to simultaneously satisfy the trade-off conditions of stress fatigue and contact pressure.

Now, the state shown by the dotted line in FIG. 11 is set to the free state, and when an external force F is applied to the free end in this state, the movable piece 26 becomes the state shown by the solid line. The force F at this time is F = 3 EIy / 1. Here, E is Young's modulus, I is the second moment of area, and y is the gap between the contacts.

The bending stress S is s = F1 / Z. Here, Z is a section modulus. Note that I and Z are constants determined by the plate thickness and width of the movable piece.

That is, as the contact pressure, which substantially corresponds to the force F, increases, the stress S also increases, so that the movable piece 26 is easily fatigued and therefore easily broken. In particular, in the case of a small leaf switch, since the effective length 1 of the movable piece 26 is limited in use, it is very difficult to reduce the stress of the movable piece 26 and increase the contact pressure.

Further, since the conventional fixed piece and movable piece are simply engaged with the side wall of the housing, they are stable against external force in the longitudinal direction thereof, but in the width direction and the plate thickness direction thereof. There was a drawback that could not be expected to be fixed sufficiently against force.

[0009]

[Problems to be solved by the device]

 The problem to be solved is that the fixed piece and the movable piece cannot be sufficiently fixed especially in the width direction and the plate thickness direction.

[0010]

【Purpose】

 In view of such conventional problems, the present invention aims to obtain a highly accurate leaf switch by securely attaching the fixed piece and the movable piece to the housing.

[0011]

[Means for Solving the Problems]

 A support wall parallel to the side wall is provided in the housing, and a protruding portion that abuts at the other end of the fixed piece is provided.One end side of the fixed piece has a side wall and a support wall in a direction intersecting the longitudinal direction. A convex portion that fits into the fitting groove formed between the two is provided.

[0012]

【Example】

 Hereinafter, a position embodiment of the present invention will be described with reference to the drawings.

That is, in FIGS. 1 to 4, the housing 1 is formed into a substantially rectangular shape, and a supporting wall 3 that is substantially parallel to the first side wall 1a is provided on one end side thereof on the longitudinal axis. The second side wall 1b and the guide wall 4 which is substantially parallel to each other are formed integrally with each other on the other end side at a predetermined interval. A guide groove 5 is formed between them by the two walls. Further, a partition wall 6 is integrally formed in the housing 1 along the longitudinal axis thereof so as to project from the bottom wall portion thereof, and the partition wall allows the housing 1 to have two chambers, that is, a first chamber 7 and a first chamber 7. It is divided into two chambers 8. The partition wall 6 is transformed at one end thereof into a reinforcing portion 11 that connects the first side wall 1a of the housing 1 and the support wall 3 to each other, and a mounting screw (not shown in the figure) is provided at an intermediate portion of the partition wall. ) Is formed with a through-hole 12 through which a through hole 12 penetrates, and a contact portion 15 is formed on the other end side of the partition wall 6 so as to intersect with the partition wall. Moreover, the reinforcing portion 11 is provided with a fitting hole 17 having a predetermined depth from the opening side of the housing 1 toward the bottom wall portion thereof, and the cylindrical portion 14 is concentric with the through hole 12 and penetrates the same. A circular fitting recess 19 having a larger diameter than the hole is formed from the opening side of the housing 1. On the first chamber 7 side, the first side wall 1a and the support wall 3 have a pair of fitting grooves 21 having a shorter dimension than the dimension between the opening side end of the housing 1 and the bottom wall 9 thereof. , 21 are provided at predetermined intervals in the direction in which they intersect with both walls 1a, 3 and further, on the second chamber 8 side, the fitting groove 21 is formed in the first side wall 1a and the support wall 3. A pair of fitting grooves 22 identical to the above are provided symmetrically around the partition wall 6, that is, the longitudinal axis of the housing 1. Then, in the fitting groove 21 on the first chamber 7 side, the first fixing piece 25 having a predetermined elasticity is fitted in the fitting groove 21a near the third side wall 1c of the housing 1. This fixing piece is formed of a band-shaped single plate, and two pairs of convex portions 27 and 28 extending in the width direction thereof are provided on one end side of the fixing piece at predetermined intervals. The width b1 of the protrusions 28a, 28b in the axial direction of the fixing piece 25 is set to be equal to or slightly larger than the distance b2 between the first side wall 1a and the support wall 3, and the adjacent protrusions 27, 2 The interval b3 between the eight is set to be larger than the thickness b4 of the first side wall 1a. A pair of protrusions 29a and 29b extending in the width direction are provided on the other end side of the fixing piece 25 so that one of the protrusions 29a is attached to the bottom wall 9 of the housing in a state of being attached to the housing. It is configured to come into contact with the protruding receiving portion 31. A circular fixed contact 33 is provided at the other end of the fixed piece 25. In the chamber 7 of the housing 1, the third side wall 1c is provided with a protrusion 32 for receiving the other end of the fixed piece 25 on the surface opposite to the surface on which the fixed contact 33 is located, substantially on the axis thereof. Has been. Further, in the first chamber 7, the first movable piece 26 is fitted in the fitting groove 21b near the reinforcing portion 11. This movable piece is formed from an elastic strip-shaped plate, and one end side of the movable piece is formed to have a thickness almost double by bending and stacking a plate body having a width of two times or more. The thickness of the fixing piece 25 is made substantially equal to. Then, in this doubled portion, convex portions 37, 38 are projected on one side thereof at a predetermined interval, and the width b1 of the convex portion 38 is fixed in the axial direction of the movable piece 26. Similar to the convex portion 28a of the piece 25, it is set to be equal to or slightly larger than the distance b2 between the first side wall 1a and the support wall 3, and the distance b6 between the adjacent convex portions 37 and 38 is also fixed. The distance b3 between the convex portions 27a and 28a is set to be larger than the thickness b4 of the first side wall 1a. The other end of the movable piece 26, that is, the free end, is provided with a movable contact 34 that selectively contacts the fixed contact 33, and this movable contact is formed in a circular shape like the fixed contact 33. The first movable piece 26 is urged so that its movable contact 34 is always separated from the fixed contact 33. That is, the first fixed piece 25 and the first movable piece 26 form a first switching element 41 that opens and closes a load having a relatively large capacity.

A second fixing piece 45 having a predetermined elasticity is fitted in the fitting groove 22b near the fourth side wall 1d of the housing 1. This fixing piece has the same shape as the first fixing piece 25.

Further, a linear fixed contact 53 having a mountain-shaped cross section is provided at the other end of the fixed piece 45 in a direction intersecting with the axial center line of the fixed piece 45. In the second chamber 8 of the housing 1, a bottom wall portion 9 thereof is provided with a holding portion 43 having a groove 42 for receiving the convex portion 29a provided on the other end side of the second fixing piece 45. As a result, the other end of the second fixing piece 45 is prevented from moving in the plate thickness direction. Further, on the fourth side wall 1d of the housing 1, there is provided a protruding portion 44 for receiving the other end of the second fixed piece 45 on the surface opposite to the surface on which the fixed contact 53 is located and substantially on the axis thereof. It is provided. The second movable piece 46 is fitted in the fitting groove 22a near the reinforcing portion 11 inside the second chamber 8. The second movable piece has the same material and structure as the first movable piece 26. The difference from the first movable piece 26 is that the dimension 12 from the support wall 3 to the free end is longer than that 11 of the first movable piece 26. Further, on the free end side of the second movable piece 46, there is provided a movable contact 54 extending in the axial direction thereof, that is, intersecting with the fixed contact 53, and having a chevron-shaped cross section like this fixed contact. There is. The second movable piece 46 is urged so that its movable contact 54 always contacts the fixed contact 53. That is, the second fixed piece 45 and the second movable piece 46 are formed with a pair of intersecting chevron points, thereby forming the second switching element 51 for opening and closing a comparatively small load.

Further, a prismatic plunger 61 is slidably accommodated in the guide groove 5, and one end of the plunger 61 penetrates the third side wall of the housing 1 and projects outward. On the other hand, a notch 10 having a predetermined length is provided in the middle of the guide wall 4. In the middle of the blanker 61, a notch 10 extends through the notch 10 toward the inside of the housing 1, and a tip of the protrusion is located on the axis of the movable contact 34 of the first movable piece 26. The first actuator 62 is integrally provided. A second actuator 63, which is a recess having a predetermined dimension h2 in the axial direction, is formed from the guide wall 4 side near the other end of the plunger 61, and a mountain-shaped convex portion is formed on the other end side. 64 are formed. The free end of the second movable piece 46 extends into the second actuator 63, that is, the recess. That is, the distance from the support wall 3 of the first movable piece 26 to the first actuator 62 is 11, while the distance from the support wall 3 of the second movable piece 46 to the second actuator, that is, the convex shape. The distance to the section 64 is set to 12. When the plunger 61 is in the first position, that is, in the upper position as shown in FIG. 1, the movable contact 34 is moved by the first actuator 62 against the biasing force of the first movable piece 26 on this axis. The movable contact 54 is separated from the fixed contact 53 against the biasing force of the second movable piece 46 by the convex portion 64, and the plunger is connected to the fixed contact 33. In the second position, that is, in the lower position as shown in FIG. 2, the first actuator 62 separates from the first movable piece 26, that is, its movable contact 34, and opens the first switching element 41. The convex portion 64 is separated from the second movable piece 46, and the movable contact 54 is brought into contact with the fixed contact 53 by the biasing force of the movable piece 46 itself.

Further, on the surface of the plunger 61 adjacent to the surface on which the first actuator 62 and the second actuator 63 are provided, an elongated hole 65 having a predetermined length h3 along the axis thereof is formed. On the other hand, the bottom wall portion of the guide groove 5 is provided with a convex portion 66 slidably engaged with the elongated hole 65. Then, when one end of the long hole 65 collates with the convex portion 66, the plunger 61 is stopped at the first position, and when the other end of the long hole 65 collides with the convex portion 66, the plunger 61 is moved to the second position. It is designed to stop at the position. A coil spring 71 is housed in the guide groove 5, one end of which is engaged with an engaging protrusion 67 provided at the other end of the plunger 61, and the other end of which is an inner surface of the fourth side wall 1d of the housing 1. Is in contact with. The coil spring has a much larger biasing force than the sum of the biasing forces of the first movable piece 26 and the second movable piece 46. Therefore, when the plunger 61 is in the non-operated state, the plunger is held in the first position, whereby the first switching element 41 forms a normally closed contact and the second switching element 51 forms a normally open contact. is doing. In the operating state of the plunger 61, that is, in the second position, the contact portion 15 prevents the first movable piece 26 from moving too far to the second switching element 51 side.

A projecting wall 16 having a fitting hole 18 of the same shape as the fitting hole 17 is integrally formed on the second side wall 1b of the housing 1 on the axis of the partition wall 6. Further, in the fourth side wall 1d of the housing 1, a through hole 13 having the same diameter as the through hole 12 is provided in a portion close to the guide wall. On one surface of the cover 81 that covers the opening of the housing 1, there are provided protrusions 83 and 84 that fit into the fitting holes 17 and 18, respectively. The diameters of these protrusions are the inner diameters of the fitting holes 17 and 18. Is set to be the same as or slightly larger than. Further, the cover 81 is provided with through holes 85 and 86 corresponding to the through holes 12 and 13. A cylindrical portion 87 that fits into the fitting recess 19 provided in the housing 1 is integrally formed at the hole edge portion of the one through hole 85. A protrusion 88 is provided on one surface of the cover 81 so as to slidably guide the plunger 61 between the cover 81 and the housing bottom wall when the cover is attached to the housing 1. In the portions corresponding to the first side wall 1a and the support wall 3, projecting walls 89 and 89 that abut against the other end edges of the fixed pieces 25 and 45 and the movable pieces 26 and 46 in the width direction are formed. Moreover, a tapered guide protrusion 90 for guiding the lower end of the sprink 71 is provided at a portion corresponding to the lower end of the guide groove 5 of the housing 1. It should be noted that both fixing pieces 25 and 45 are warped outward in advance so that the fixed contact points 33 and 53 are elastically abutted with the projecting portions 32 and 44 in a fitted state with the fitting grooves 21 and 22, respectively. It is slightly curved.

Further, when the cover 81 is attached to the housing 1, the convex portions 28b, 28b of the two fixing pieces 25, 45 are located in the recess 80 of the cover 81 as shown in FIG. Convex portions 29b, 29b of the cover 81 come into contact with the inner surface of the cover 81, and the side ends of the fixed pieces 25, 45 and the movable pieces 26, 46 come into contact with the projecting walls 89, 89 of the cover 81. The pieces 25 and 45 and the two movable pieces 26 and 46 are fixed.

[0020]

【motion】

 1, the plunger 61 is at the first position, that is, at the upper side, and the projection 66 is at one end of the elongated hole 65, that is, near the lower end. Therefore, the movable contact 34 is in contact with the fixed contact 33 by the first operating element 62 located immediately below the movable contact 34. Therefore, the first switching element 41 is in the closed state. At the same time, the movable contact 54 is separated from the fixed contact 53 by the convex portion 64, so that the second switching element 51 is in the open state.

Next, when the plunger 61 is pressed and moved to the second position, that is, downward as shown in FIG. 2, the convex portion 66 abuts against the other end of the elongated hole 65, that is, the upper end, and thus the first portion The operator 62 is separated from the movable contact 34 and opens the first movable contact 26. Therefore, the movable contact is separated from the fixed contact 33 by the urging force of the first movable piece 26. Then, the first movable piece 26 comes into contact with the abutting portion 15 and is held at this position, so that the first switching element 41 is in an open state. At the same time, the convex portion 64 separates from the second movable piece 46 and opens the movable piece. Therefore, the movable piece moves to the second fixed piece 45 side by the urging force, and the movable contact 54 comes into contact with the fixed contact 53, so that the second switching element 51 is closed.

In this state, the plunger 61 does not come into contact with the first movable piece 26 or the second movable piece 46, that is, the first movable piece 26 and the second movable piece 46 have the plunger 61. Is free to. Next, when the pressing of the plunger 61 is stopped, the plunger returns to its original state by the urging force of the coil spring 71, and the first switching element 41 and the second switching element 51 are also shown in FIG. The state shown in 1 is restored.

[0023]

[Effect of device]

 According to this invention, as described above, the housings 1 are provided with the protrusions 32 and 44 that abut at the other ends of the fixing pieces 25 and 45 in the fitted state of the fixing pieces 25 and 45 with respect to the housing 1. On one end side of the fixing pieces 25, 45, convex portions 28a, 28b, 38 having a width b1 which is equal to or slightly wider than the distance between the one side wall 1a and the supporting wall 3 in a direction intersecting the longitudinal direction thereof. Of the two fixed pieces 25, 45 and the two movable pieces 26, 46 are fitted into the fitting grooves 21, 22, respectively, and the respective convex portions 28a, 28b, 38 are formed on the side wall 1a and the support wall 3 respectively. The fixing pieces 25, 45 are pressed into each other, and the fixing pieces 25, 45 are abutted against the protrusions 32, 44 by the elasticity of the respective fixing pieces, and the cover 81 is attached to the housing 1. And both movable pieces 2 , 46 are fixed, and further, both fixed pieces 25, 45 and both movable pieces 26, 46 are prevented from moving in the width direction, so that there is an advantage that a switch with extremely high operation accuracy can be obtained. .

Generally, since the movable piece having a spring property has a small plate thickness, it is difficult to form the fitting groove 21 as shown in FIG. This is because the mold 100 is formed by a thin metal piece 101 as shown in FIG. 13, and is caused by deformation during molding. However, according to the present invention, since each metal piece 101 of the mold 100 can be reinforced by the connecting portion 102 as shown in FIG. 14, there is no fear that the metal piece 101 will be deformed even when the molding material is pressed in. .

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a leaf switch according to the present invention with a cover removed.

FIG. 2 is a front view for explaining the operation of the leaf switch according to the present invention.

FIG. 3 is an exploded perspective view of a leaf switch according to the present invention.

FIG. 4 is an external perspective view of a leaf switch according to the present invention.

FIG. 5 is a perspective view of an essential part of a leaf switch according to the present invention.

6 is a sectional view taken along line 6-6 of FIG.

7 is a cross-sectional view taken along line 7-7 of FIG.

FIG. 8 is a front view showing the relationship between the fixed piece of the leaf switch and the housing according to the present invention.

FIG. 9 is an operation explanatory view for explaining the operation of the conventional leaf switch.

FIG. 10 is an operation explanatory view for explaining the operation of the conventional leaf switch.

FIG. 11 is an exploded view of a conventional leaf switch.

FIG. 12 is a front view showing a part of a housing of a conventional leaf switch.

FIG. 13 is a perspective view showing a conventional mold.

FIG. 14 is a perspective view of a leaf switch mold according to the present invention.

[Explanation of symbols]

 1 Housing 1a Side Wall 1b Side Wall 1c Side Wall 1d Side Wall 3 Support Wall 4 Guide Wall 5 Guide Groove 6 Partition 7 First Chamber 8 Second Chamber 9 Bottom Wall 10 Notch 11 Reinforcement 12 Through Hole 13 Through Hole 14 Tube Part 15 Contact part 16 Projection wall 17 Fitting hole 18 Fitting hole 19 Fitting recess 21 Fitting groove 22 Fitting groove 25 First fixed piece 26 First movable piece 27 Convex section 28 Convex section 29 Convex section 31 Receiving part 32 Protruding part 33 Fixed contact 34 Movable contact 37 Convex part 38 Convex part 41 First switching element 42 Groove 43 Holding part 44 Protruding part 45 Second fixed piece 46 Second movable piece 51 Second switching element 53 Fixed contact 54 Movable contact 61 Blanker 62 First operator 63 Second operator 64 Convex portion 65 Elongated hole 66 Convex portion 67 Engaging protrusion 71 Coil spring 80 Recess 81 Cover 8 Projections 84 projections 85 through hole 86 through hole 87 tubular portion 88 rib 89 projecting walls 90 guide protrusions 100 die 101 metal pieces 102 coupling portion

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] May 2, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Fig. 10

[Correction method] Delete

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 11

[Correction method] Delete

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] Fig. 12

[Correction method] Delete

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] Fig. 13

[Correction method] Delete

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] Fig. 14

[Correction method] Delete

Claims (1)

[Scope of utility model registration request] A normally-closed switching element including a first fixed piece (25) having a fixed contact (33) and a first movable piece (26) having a movable contact (34) selectively contacting the first fixed piece. And a second movable piece (46) having a fixed contact (53) and a movable contact (54) for selectively contacting the second fixed piece (45).
A normally open switching element is constituted by the above, and a support wall (3) substantially parallel to the one side wall (1a) is integrally formed in the housing (1) accommodating both of these switching elements with a predetermined interval therebetween. Both walls (1
In a) and (3), fitting grooves (21a) and (21b) for fitting one end sides of the fixed pieces (25) (45) and the movable pieces (26) (46) in a direction intersecting these walls. (22
a) (22b) are formed with a predetermined distance between each other and with a predetermined depth, while the above-mentioned housing (1) is formed.
Inside of the two fixing pieces (25) (4), the two fixing pieces (25) (45) are fitted in the housing (1).
At the other end of 5), a protrusion (32) (44) that abuts a surface opposite to the surface on which each fixed contact is provided is provided, and one end side of both the fixing pieces (25) (45) is provided. Has a protrusion (28a) (28b) having a width (b1) which is equal to or slightly wider than the distance between the one side wall (1a) and the support wall (3) in a direction intersecting the longitudinal direction. (3
8), and the fitting grooves (21a) of the fixed pieces (25) (45) and the movable pieces (26) (46).
The protrusions (28a) (28b) (38) are press-fitted between the one side wall (1a) and the support wall (3) in a fitted state with respect to (21b) (22a) (22b) and the above-mentioned fixing Put the pieces (25) (45) on the protrusions (32) (4).
4) are made to abut against each other by the elasticity of the respective fixing pieces, and a cover (81) for covering the opening is attached to the housing (1) so that both fixing pieces (2)
5) A leaf switch adapted to fix both (45) and the movable pieces (26) (46).