JPH09320397A - Switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a structure, and reduce the load of contact pieces so as to enhance stroke accuracy by fitting a moving contact piece to an actuator directly, journalling the same to a board in which contact patterns are embedded through integrally molding with an operation element, and slidingly touching the arc-like contact pieces to the contact patterns in the turning direction of the actuator. SOLUTION: A switch 40 is composed of a board 41 in which contact patterns are embedded, an operation element 45 integrally molded with an actuator 43 to which a moving contact piece 42 is fitted, a coil spring 46 which elastically biases the actuator 43. The respective patterns 53a, 51a, and 52a of a common contact, a normally-closed contact, and a normally-opened contact are successively arranged in the radial direction of a shaft hole 54 provided in the plate portion 48 of the board 41 journalling the actuator 43, and are elastically touched by the arc-like contact pieces 64 of the moving contact piece 42, and are slidingly touched with the turning of the actuator 43. The respective contact pieces 64 extend and slide arc-like along the turning direction of the actuator 43 so that the load thereof is little, and the contact pieces is hardly deformed so as to obtain excellent and stable stroke accuracy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch suitable for use as, for example, a micro switch for position detection.

[0002]

2. Description of the Related Art As a switch of this type, a switch for switching contacts in a snap action system has been widely used, and an example of its structure is shown in FIG. A movable contact piece 12 is swingably engaged with and supported by the common terminal 11, and a tip end side of the movable contact piece 12 and an extension portion 11 a of the common terminal 11 are supported.
A reversing spring 13 made of a leaf spring is arranged between and. In this example, the movable contact piece 12 and the reversing spring 13 are integrally formed, and the tip of the movable contact piece 12 is positioned between the normally closed contact 14 and the normally open contact 15 to form a movable contact 16. It

An actuator 18 whose one end is rotatably supported by the case 17 is pressed to operate the actuator 18.
Movable contact piece 1 by push button 19 pushed in by
By pressing and displacing the intermediate portion of 2, the reversing spring 1
3 performs a snap operation, whereby contact switching by the movable contact 16 is performed. The actuator 18 is attached in order to lengthen the operation stroke.

In the snap action type switch 10 shown in FIG. 9, the movable contact 16 comes into contact with the normally open contact 15 or the normally closed contact 14 by the switching operation and has a so-called batting contact structure, so that the same portion is always present. As a result, contact deterioration is likely to occur and the contact does not have a self-cleaning function. Therefore, if an oxide film or dirt is generated on the contact, there is a problem that contact instability easily occurs, for example, when the operating current is very small. Furthermore, the reversing spring 1
Since 3 is used, a low contact load results in a low contact pressure, and when vibration or impact is applied, for example, a contact in an ON state is likely to be turned OFF instantly, and this also causes a problem in contact stability. It was a thing.

On the other hand, a switch adopting a sliding contact structure can be considered as a structure capable of avoiding the above-mentioned problems. FIG. 10 shows a switch described in Japanese Patent Laid-Open No. 7-6661 as this type of switch. The switch 20 includes a slider 22 slidably held on a wafer 21 which also serves as a lower case, a movable contact 23 attached to the slider 22, a slider 22 and the wafer 21.
The conductive return spring 25 is arranged between the common contact 24 arranged on the bottom surface of the slider and biases the slider 22 upward in the drawing.
A normally closed contact 26 and a normally open contact 27 arranged on the wall surface of the wafer 21, and a slider 22 mounted on the wafer 21.
Of the elastic cap 28 that covers the operator 22a of the
And a movable contact 23 and a common contact 24. The upper case 31 accommodates the cap 28 protruding from the opening 29 and the actuator 32 pivotally supported by the upper case 31 and abutting the cap 28. Is the return spring 25
It is always conducted through.

The elastic piece 23a of the movable contact 23 is the wafer 21.
Of the normally closed contact 26 and the normally open contact 27 are slidably contacted, and the actuator 32 is pushed to push the operating element 22a, that is, by moving the slider 22 in the vertical direction, The piece 23a slides to switch the contacts.

[0007]

Since the switch 20 shown in FIG. 10 has a sliding contact structure,
Due to the self-cleaning function, a good contact state of the contact can be obtained, and since the pressing direction (contact pressure direction) of the elastic piece 23a of the movable contact 23 is different from the pressing operation direction of the actuator 32, the contact pressure is increased. Also, the increase rate of the operating load on the actuator 32 is small, that is, a high contact pressure can be realized at a low operating load, and a stable contact state can be obtained even when vibration or shock is applied.

However, in the switch 20, the elastic piece 23a of the movable contact 23, which is in sliding contact with the normally closed contact 26 and the normally open contact 27, is slidable in the direction perpendicular to the extending direction, that is, in the width direction. Therefore, the elastic piece 23
The structure is such that a is easily loaded, that is, it is easily bent or deformed in the width direction. Therefore, the contact switching timing may be deviated, and the contact ON / OFF good and stable stroke accuracy may not be obtained. Has become.

The displacement of the actuator 32 is transmitted to the elastic piece 23a via the cap 28 and the slider 22, and the actuator 32 is transferred to the upper case 31 which is separate from the wafer 21 on which the contacts 26 and 27 are arranged. Since it is attached, the stroke accuracy is difficult to obtain even with such a complicated structure, and the number of parts is large.

An object of the present invention is to solve these drawbacks, to provide a switch having a sliding contact structure having a small number of parts, a simple structure and excellent stroke accuracy.

[0011]

According to the first aspect of the invention, a switch that performs a switching operation by depressing an operator has a substrate having at least two contact patterns embedded in a plate surface and one end thereof. An actuator that is engaged with the substrate and is rotatable around one end of the substrate along the plate surface of the substrate, and has an arc shape that is substantially along the rotation direction of the actuator. One end is fixed to the actuator and the other end A movable contact piece whose side is slidably contactable with each of the contact patterns, a substrate, a box-shaped cover for accommodating the actuator and the movable contact piece, and the other end of the actuator are integrally formed so as to project in the rotation direction, It is composed of an operator protruding to the outside through an opening formed on the upper surface of the cover, and means for elastically biasing the actuator in a direction in which the operator protrudes from the opening.

According to a second aspect of the present invention, in the first aspect of the present invention, one end of the actuator is integrally provided with a shaft serving as a rotation center, and the shaft is axially supported by a shaft hole formed in the substrate. According to the invention of claim 3, in the invention of claim 2, the elastic biasing means is a torsion coil spring attached to the shaft, one arm of the torsion coil spring is locked to the actuator, and the other arm is fixed to the cover. Be locked.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, the operating element has a tapered shape in which a cross section of a plane parallel to the rotation plane of the actuator is substantially triangular, and is perpendicular to the upper surface of the cover. The actuator is rotated by the pressing operation in either the direction or the parallel direction. According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, a normally-closed contact pattern, a normally-open contact pattern, and a common contact pattern are embedded in the substrate, and the common contact pattern is on a center side in a radial direction of rotation of the actuator. The normally-closed contact pattern and the normally-open contact pattern are arranged in the circumferential direction on the outer side in the radial direction of rotation.

According to the invention of claim 6, in the invention of claim 5, the shapes of the normally closed contact pattern and the normally open contact pattern are:
It is selected so that the shorting switching is performed.

[0015]

Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows the appearance of an embodiment of the present invention, and FIG. 2 shows the internal structure thereof. In this example, the switch 40 includes a substrate 41 having a contact pattern embedded therein, an actuator 43 to which a movable contact piece 42 is attached and which rotates along a plate surface of the substrate 41, and a cover 4 formed integrally with the actuator 43.
4 and an actuator 4 protruding outside the actuator 4
3 and a torsion coil spring 46 that elastically biases the element 3. First, the configuration of each component will be described below.

The substrate 41 has a base portion 4 as shown in FIG.
7 and a plate portion 48 standing upright from the base portion 47, and the metal terminal is insert-molded. This example has a three-terminal structure, and a normally closed terminal 51, a normally open terminal 52, and a common terminal 53 are projected from the lower surface of the base portion 47. The other end sides of these terminals 51, 52 and 53 are embedded in the plate surface of the plate portion 48 to form a normally closed contact pattern 51a, a normally open contact pattern 52a and a common contact pattern 53a, respectively.

A shaft hole 54 for pivotally supporting the actuator 43 is formed in a corner portion on the upper end side of the plate portion 48, and a common contact pattern 53a is formed on the center side in the radial direction centered on the shaft hole 54. Is located, and the normally-closed contact pattern 51a and the normally-open contact pattern 52a are arranged in the circumferential direction outside thereof. In addition, each contact pattern 51a-
53a are separated from each other by a predetermined amount. The pair of through holes 55 provided in the base portion 47 are holes for screws to which the switch 40 is attached.

The actuator 43 has a shape as shown in FIG. 4, and a protrusion 57 is integrally formed on the center of the fan of the substantially fan-shaped movable portion 56, and a shaft 58 is provided on the protrusion 57.
Are integrally formed so as to be perpendicular to the plate surface of the movable portion 56. The shaft 58 is rotatably supported by the shaft hole 54 of the base plate 41 described above, so that the actuator 43 is supported by the shaft 5.
It is rotatable about the plate 8 along the plate portion 48 of the base portion 41.

An arm 59 is provided on the outer peripheral side of the movable portion 56 so as to project in the radial direction of rotation, the arm 59 is bent and extended in the rotational direction (circumferential direction), and an operating element 45 is provided at the tip thereof. To be In this example, the operator 45 provided so as to project from the actuator 43 in the rotation direction has a tapered shape in which a cross section of a plane parallel to the rotation plane of the actuator 43 forms a substantially triangular shape. A through hole 61 is provided in the central portion of. A pair of mounting shafts 62 for mounting the movable contact piece 42 and a positioning boss 63 are projectingly provided on the plate surface of the movable portion 56.

As shown in FIG. 5, the movable contact piece 42 is a so-called brush-like member made of a leaf spring material. In this example, the movable contact piece 42 has three arc-shaped contact pieces 64 connected at one end side. The tip side of the piece 64 is further divided into two pieces, and is bent to form contacts. Each contact piece 64 is bent so as to form a predetermined rising angle with respect to the connecting portion 65. A pair of mounting holes 66 are formed in the connecting portion 65.

The movable contact piece 42 is attached to the actuator 43 by passing the attachment hole 66 through the attachment shaft 62 and then crushing the head of the attachment shaft 62 to prevent it from coming off. FIG. 6 shows this mounting state. In this state, the arcuate contact pieces 64 of the movable contact piece 42 are substantially along the turning direction of the actuator 43.

The cover 44 is constructed as shown in FIG. That is, it is formed into a box shape having a substantially rectangular parallelepiped shape with one surface open, and a pair of oval notches 67 are formed at the open end edges of both side surfaces 44a and 44b along the longitudinal direction thereof. The notch 67 is formed in the base portion 47 of the substrate 41 described above.
This is a relief for the portion where the through hole 55 is formed. Further, a rectangular hole 68 is formed between the notches 67 on the side surface 44a, and a locking portion 69 slightly protruding from the notches 67 is formed at the end edge between the notches 67 on the other side surface 44b. ing. An opening 71 for projecting the operator 45 is formed on one side of the upper surface of the cover 44.

FIG. 8 shows a torsion coil spring 46 that elastically biases the actuator 43. Next, the assembly of the switch 40 will be described. As shown in FIG. 6, after the torsion coil spring 46 is attached to the shaft 58 of the actuator 43 to which the movable contact piece 42 is attached, the shaft 58 is inserted into the shaft hole 54 of the substrate 41. Then, the cover 44 is covered from the plate portion 48 side of the substrate 41. The engagement portion 69 of the cover 44 is engaged with the step portion 72 provided on the base portion 47 of the substrate 41, and the hole 68 is provided with a protrusion (not shown) protruding from the back surface of the plate portion 48. The switch 40 is completed by attaching the cover 44 in this manner.

The plate portion 48 of the substrate 41, the actuator 43, the movable contact piece 42 and the torsion coil spring 46 are accommodated in the cover 44, and the operator 45 is projected to the outside through the opening 71 of the cover 44. The torsion coil spring 46
As shown in FIG. 2, one arm 46 a is pressed by a stopper 73 projecting from the actuator 43 and locked by the actuator 43, and the other arm 46 b is brought into contact with the inner wall of the cover 44 and attached to the cover 44. Be locked. Therefore, the actuator 43 is elastically biased by the torsion coil spring 46 in the direction in which the operating element 45 projects from the opening 71.

Each contact piece 64 of the movable contact piece 42 attached to the actuator 43 has each contact pattern 51a.
It is elastically contacted with the plate surface of the plate portion 48 in which 53a is embedded, and is slidably contacted with these contact patterns 51a to 53a by the rotation of the actuator 43. In the switch 40, as shown in FIG. 2, the normally closed contact pattern 51a and the common contact pattern 53a are always connected to each other through the movable contact piece 42, and the operator 45 is pressed to rotate the actuator 43. By doing so, the movable contact piece 42 slides to perform contact switching, and the normally open contact pattern 52a and the common contact pattern 53a are electrically connected. In FIG. 2, the position of the operator 45 indicated by the chain double-dashed line indicates the position pushed in by the pressing operation. By releasing the pressing, the operator 45 returns to the position indicated by the solid line.

In this example, the operation element 45 can be pushed in either vertically (arrow A) or vertically (arrow B) on the upper surface of the cover 44. That is, in this example, since the operator 45 has a substantially triangular cross section, the operator 45 is pushed in by the force of the inclined surface 45a even when operated in the direction of the arrow B, and the actuator 43 is rotated.

According to the switch 40 described above, each contact piece 64 of the movable contact piece 42 is extended in an arc shape substantially along the rotation direction of the actuator 43 and is slid in the extension direction, so that a load is less likely to be applied. In that direction, it has excellent rigidity and is hard to deform. In addition, the operator 45
The movable contact piece 4 is directly movable to the actuator 43 integrally formed with
2 is attached, and the actuator 43 is directly supported by the substrate 41 in which the contact patterns 51a to 53a are embedded. Therefore, the number of parts is small, the configuration is simple, and the dimensional accuracy is easy to obtain. From these points, it is possible to obtain good and stable stroke accuracy with a simple configuration.

Although the three-terminal structure is used in the above-mentioned example, a two-terminal structure is also possible.
2 (normally open contact pattern 52a) or a normally closed terminal 51 (normally closed contact pattern 51a) may be omitted. By making the operator 45 have a shape as shown in this example, the actuator 43 can be favorably rotated, that is, the switch 40 can be favorably operated even by the operation in the direction of the arrow B shown in FIG. Become a thing,
Therefore, it is suitable when such a usage state is required. In addition, for example, when the operation element 45 is used by the operation in the direction of the arrow A, the operation element 45 may have another shape having no inclined surface 45a.

Further, in this example, the substrate 41 is provided with the shaft hole 54 and the actuator 43 is formed with the shaft 58 pivotally supported by the shaft hole 54.
A shaft hole may be formed in the actuator 43. The shapes of the normally closed contact pattern 51a and the normally open contact pattern 52a are
Contact piece 64 of movable contact piece 42 when actuator 43 rotates
Shorting switching can be realized if there is a timing at which they are conducted through, while non-shorting switching is performed if they are not conducted. Any of the toning products can be easily manufactured.

[0030]

As described above, according to the present invention, a switch having a sliding contact structure which is excellent in contact stability against vibration, shock, or minute current can be simply and inexpensively constructed with a small number of parts. In addition, it is possible to obtain a switch having good and stable stroke accuracy.

Further, according to the invention of claim 4, the operator 4
It is possible to obtain a switch that operates well even by an operation in the direction of the arrow B parallel to the upper surface of the cover 44 from which 5 projects, and thus a switch with excellent versatility can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a partial sectional view of FIG.

FIG. 3 is a perspective view of the substrate shown in FIG.

FIG. 4 is a perspective view of the actuator shown in FIG.

5A is a front view of the movable contact piece in FIG. 2, and B is a side view thereof.

FIG. 6 is a front view showing a state where a movable contact piece is attached to an actuator.

FIG. 7 is a perspective view of the cover in FIG.

FIG. 8 is a perspective view of the torsion coil spring in FIG.

FIG. 9A is a partial cross-sectional view showing an example of a conventional switch,
B is the perspective view which abbreviate | omitted a part of A and was shown.

FIG. 10 is a sectional view showing another example of a conventional switch.

Claims (6)

[Claims] 1. A switch which is switched by pressing an operating element, a substrate having at least two contact patterns embedded in a plate surface, one end of which is engaged with the substrate, and one end of which is the center. An actuator that is rotatable along the plate surface of the substrate, and has an arc shape that extends substantially along the rotation direction of the actuator, one end side is fixed to the actuator, and the other end side is in sliding contact with each contact pattern. A movable contact piece that is made possible, a box-shaped cover that accommodates the substrate, the actuator, and the movable contact piece, is integrally formed at the other end of the actuator so as to project in the rotation direction, and is formed on the upper surface of the cover. The operator protruding outward through the opened opening, and means for elastically biasing the actuator in a direction in which the operator protrudes from the opening. Switch characterized by. 2. The switch according to claim 1, wherein a shaft serving as a rotation center is integrally projectingly provided at the one end of the actuator, and the shaft is axially supported by a shaft hole formed in the substrate. Switch characterized by. 3. The switch according to claim 2, wherein the elastic biasing means is a torsion coil spring attached to the shaft, one arm of the torsion coil spring is locked to the actuator, and the other arm is A switch characterized by being locked to the cover. 4. The switch according to any one of claims 1 to 3, wherein the operating element has a tapered shape in which a cross section of a plane parallel to a rotation plane of the actuator is substantially triangular, and is perpendicular to an upper surface of the cover. A switch characterized in that the actuator is rotated by the pressing operation in both the parallel and parallel directions. 5. The switch according to claim 1, wherein a normally closed contact pattern, a normally open contact pattern and a common contact pattern are embedded in the substrate, and the common contact pattern is a turning radius of the actuator. A switch characterized in that it is located on the center side in the direction, and the normally-closed contact pattern and the normally-open contact pattern are arranged in the circumferential direction on the outer side in the radial direction of rotation. 6. The switch according to claim 5, wherein the shapes of the normally closed contact pattern and the normally open contact pattern are selected so that shorting switching is performed.