JP4041472B2 - Press switch unit - Google Patents

Description

  The present invention relates to a push switch unit in which a switch is turned on by a push operation on a knob.

A conventional press switch unit is shown in FIG. A circular opening 1b is formed in the surface plate 1a of the flat rectangular case 1, a knob 2 is arranged in the case 1 so as to close the opening 1b, a membrane switch 3 is attached to the inner surface of the back plate 1c, and the knob 2 and the membrane switch 3, the click plate 4 is arranged on the side of the knob 3, the convex side of the click plate 4 is the knob 2 side, the center of the click plate 4 faces the switch 3, and the knob 2 is the surface plate by the elastic force of the click plate 4. It is press-contacted to 1a.
When the knob 2 is pressed into the case 1, the knob 2 moves toward the back plate 1 c, and when the pressing force exceeds a certain value, the click plate 4 is reversely elastically deformed, and the switch 3 is moved by the center of the click plate 4. Is pushed by the back plate 1c, and the switch 3 is turned on. When the pressing force is released, the click plate 4 returns to its original shape by the elastic force, the knob 2 is pressed against the surface plate 1a, and the switch 3 is turned off.

In the conventional push switch unit, the knob diameter _{D C} of the click plate 4 is small become soluble with respect to the diameter _{D N} of the second pressing portion 2a that case bulging outwardly, for example _D N = 10 mm when _{D C} of 3 About 6 mm. Therefore, as shown in an enlarged view in FIG. 15, when the center of the pressing portion 2 a is pressed as indicated by a solid line arrow, the center point 4 a of the click plate 4 is on the back plate 1 c side on the center line 5 of the click plate 4. Are pressed at right angles to each other, and the portions on the entire periphery of the click plate 4 are uniformly subjected to the reaction force from the back plate 1c.
However, when the pressing portion 2a is pressed at one place close to the periphery of the pressing portion 2a as shown by a broken line arrow, and the so-called end pressing is performed, the curvature radius of the curved surface of the click plate 4 is relatively small. As shown, the pressing portion 2a is inclined, and a point 4b shifted from the center point 4a of the click plate 4 receives a pressing force in a direction inclined with respect to the center line 5 and the back plate 1c as indicated by a broken line 6. That is, since the distance from the opening surface of the click plate 4 to the action point 4b is smaller than the distance b1 from the center point 4a, the reaction force that the entire periphery of the click plate 4 receives from the back plate 1c is not uniform in each part, and is greatly different. As a result, the click plate may be permanently deformed, the life is short, and the touch is remarkably impaired.

The pressure switch unit according to the present invention includes a case in which an opening is formed in a surface plate, a knob provided in the case and facing the outside from the opening, and a curve made of an elastic material disposed between the knob and the back plate of the case. A member, and a switch disposed between the knob and the back plate of the case and operated by pressing the knob. The knob includes a reinforcing plate that is movable in a direction perpendicular to the back plate, a knob cover that is provided on the front plate side of the reinforcing plate and includes a plurality of divided pressing portions, and each divided pressing portion between the knob cover and the reinforcing plate. A plurality of first-stage press detection units that are provided for each and are operated by a press that is weaker than the reaction force of the bending member against the split press part. The bending member has an annular peripheral portion that contacts the periphery of the reinforcing plate, and a flat plate portion that is located on the outer peripheral side of the peripheral portion and supports the peripheral portion via the support portion.

Since the bending member has an annular peripheral portion that contacts the periphery of the reinforcing plate and a flat plate portion that is positioned on the outer peripheral side of the peripheral portion and supports the peripheral portion via the support portion, even if the knob is pushed to the end. The force in the rotational direction does not substantially act on the bending member. For this reason, there is no possibility that the lifetime of the bending member will be shortened, and it is difficult for permanent deformation to occur.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below. Corresponding components in a plurality of drawings to be referred to are assigned the same reference numerals, and redundant descriptions are omitted.
[First Embodiment]
A first embodiment of the present invention will be described with reference to FIGS. An opening 21b is formed in the surface plate 21a of the case 21, and a knob 22 is disposed so as to substantially close the opening 21b and face the outside. A switch 23 is attached to the inner surface (back surface) of the knob 22, and the switch 23 and the case 21 A curved member 24 made of an elastic material having a convex on the back plate 21c side is interposed between the back plate 21c and the back plate 21c. The bending member 24 has a size that substantially includes the pressing portion 22 a of the knob 22. When the knob 22 is pressed and displaced toward the back plate 21c, the bending member 24 is elastically deformed. Due to the deformation, the switch 23 is operated and turned on. When the pressing is released, the bending member 24 is elastically restored to its original shape. Then, the knob 22 is returned to the original position, and the switch 23 is turned off.

In this example, the case 21 has a thin rectangular parallelepiped shape, and the opening 21b is circular. The knob 22 has a disk shape, and the inner surface thereof is a plane parallel to the back plate 21c, and the surface (the outer surface of the case) is a part of a spherical surface having the same axis as the axis of the knob 22 and a large radius. Thus, the pressing portion 22 bulges outwardly, and a collar 22b is formed on the peripheral surface of the pressing portion 22a so as to extend in the radial direction. The collar 22b is in contact with the peripheral edge of the opening 21b of the surface plate 21a by the elastic force of the curved portion 24.
In this example, the switch 23 is a membrane switch. That is, as shown in a cross-sectional view in FIG. 5, a spacer 23c is interposed between flexible films 23a and 23b such as a polyethylene film, and a pair of fixed contacts 23d and 23e and the outside thereof are provided on the inner surface of one flexible film 23a. A lead wire (not shown) is printed and wired, and a movable contact 23f is formed on the other flexible film 23b so as to face the fixed contacts 23d and 23e by a printed wiring technique. In this example, the flexible films 23a and 23b constituting the membrane switch 23 are extended and extended in a square shape to form a membrane sheet 23g, and a central portion of one side thereof is a signal lead-out portion (tail portion) 23h and is provided outside the case 21. Is derived. Lead wires for the fixed contacts 23d and 23e are printed in the signal lead-out portion 23h. 2 and 3, since the membrane switch 23 is thin, it is difficult to understand each contact, and therefore, the membrane switch 23g is shown as a blank portion.

  A rectangular notch 21e is formed in the side wall 21d of the case 21, and a signal lead-out portion 23h is passed through the notch 21e so as to be brought out of the case 21. The back plate 21c of the case 21 is a separate metal plate, and the front plate 21a and the side wall 21d of the case 21 are molded products of hard resin such as ABS resin and polycarbonate, and are formed on the back side end surface of the side wall 21d. The back plate 21c is fixed in contact. For example, the inner peripheral surface of the case 21 is circular, and the bosses 21f are integrally formed on the back surface of the side wall 21d in contact with the inner peripheral surface of the case 21 so as to correspond to the corners of the case 21, and these bosses 21f are formed in a rectangular metal back It passes through holes 21c1 formed in the corners of the face plate 21c, and its protruding end is heated and expanded, and the back plate 21c is fixed to the side wall 21d by so-called heat caulking.

In this example, as the bending portion 24, when the center portion is reversed with a click feeling when a pressure of a predetermined value or more is used, an elastic metal plate click plate is used as the bending member 24 with the click feeling. Is used. The click plate 24 is arranged such that a circular elastic metal plate is curved in a shallow dish shape, and its convex side is a back plate 21c. The diameter _{D N} of the same degree of pressure portion 22a of the diameter _{D C} is the knob 22 of the circular dish-shaped click plate 24, that is more than 0.7 times the diameter _{D N} of the pressing portion 22a _{(D C} ≧ 0.7D _N) It is said. However, the distance b1 between the opening surface of the bending member 24 and the center point of the outer surface is set to be approximately the same as that in the conventional press switch unit. Further, in this example, a projection 21c2 is formed at the center of the inner surface of the back plate 21c so as to face the center of the bending member 24 so that the click plate 24 is reversed with a predetermined pressing force. In this example, the protrusion 21c2 is formed by pressing the back plate 21c of a metal plate. Length of one side of the membrane sheet 23g is set to be larger than the diameter D _C of the click plate 24, the peripheral edge of the click plate 24 is always in contact with the membrane sheet 23g.

  Although the membrane sheet 23g is not shown in the drawing, the knob 22 is attached to the knob 22 by, for example, a double-sided adhesive tape, and the membrane switch 23 is visually aligned with, for example, a marker attached when the knob 22 is formed. It is assumed that the flexible film of the membrane switch 23 is transparent. Similarly, the click plate 24 is visually aligned with the membrane switch 23. For example, the click plate 24 is covered and an adhesive tape 25 (see FIG. 4, not shown in FIGS. 2 and 3) is attached to the membrane sheet 23g. Then, the click plate 24 is attached to the knob 22. Thereafter, the knob 22 with the click plate 24 is put into the case 21 from the back side, and the back plate 21c is fixed to the side wall 21d as described above, for example. In this configuration, when the pressing portion 22a of the knob 22 is pressed toward the inside of the case 21, the center portion of the click plate 24 is pressed against the knob 22 side by the projection 21c2, and the pressing force becomes a predetermined value or more, FIG. As shown, the center portion of the click plate 24 is inverted with a click feeling, the membrane switch 23 is pressed against the knob 22 by the inverted center portion, the flexible film 23b is bent, and the movable contact 23f is fixed contact 23d. And the switch 23 is turned on. At this time, the knob 22 is displaced to the back plate 21c side. When the pressure on the knob 22 is released, the click plate 24 is restored to its original shape by its elastic restoring force, the knob 22 is displaced to the surface plate 21a side, and the collar 22b comes into contact with the surface plate 21a. The restoring force of 23b returns to the original shape, and the switch 23 is turned off.

Even if the pressing portion 22a is pressed away from the central portion thereof, for example, the portion indicated by the solid line arrow in FIG. 3, the click plate 24 has a large area and faces almost the entire pressing portion 22a. Therefore, the distance between the pressing action point received by the click plate 24 and the opening surface of the click plate 24 is substantially the same as b1, and the pressing force is uniformly distributed and applied to the entire peripheral portion of the click plate 24. The force component that the knob 22 tries to rotate around the protrusion 21c2 does not occur.
Note the area surrounding the periphery of the click plate 24, be slightly smaller than the area surrounding the peripheral edge of the pressing portion 22a, also for example the diameter D _C of the click plate 24 is 0.7 times the diameter D _N of the pressing portion 22b Specifically, even if D _N = 20 mm and D _C = 14 mm, even if one part of the peripheral edge of the pressing portion 22b is pressed as shown by a broken line arrow in FIG. The component that tries to rotate the knob 22 by the received pressing force on the entire periphery of the click plate 24 is the pressing force when the distance between the pressing point and the periphery of the click plate 24 is d1 when viewed from the direction perpendicular to the back plate 21c. It is very small divided by the ratio of d1: D _C / 2, and does not affect the touch feeling of the switch operation.

As described above, according to the present invention, the force received by the knob 22 acts in a direction perpendicular to the back plate 21c regardless of which portion in the pressing portion 22a is pressed, that is, the end is pressed. 21c is displaced to the back plate 21c side in a state parallel to 21c, and can always be operated with the same switch operation feeling, the click plate (curved member) 24 is not permanently deformed, has a long life, and in this example is always the same. A click feeling is obtained.
[Second Embodiment]
In the second embodiment, the present invention is applied to a two-stage press switch unit in which a first-stage switch as a first-stage press detection unit is operated by a pressing operation, and the second-stage switch is operated by further pressing. .

  As shown in FIGS. 7 to 9, a knob cover 22 d is used as the knob 22 in parallel with the back plate 21 c and displaceable in a direction perpendicular to the back plate 21 c, and the front plate side of the reinforcement plate 22 c. The knob cover 22d is provided with a plurality of divided pressing portions 22a1. Corresponding to each of the divided pressing portions 22a1, the reinforcing plate 22c is provided with a first step switch 31a as a first step pressing detection portion. A switch 23, in this example a membrane sheet 23g, is attached to the surface of the reinforcing plate 22c on the back plate 21c side. A bending member 24 is interposed between the reinforcing plate 22c and the back plate 21c.

  Specific examples of each part will be described below. In this example, the knob cover 22d is configured by forming a split pressing portion 22a1 on a very flexible elastic sheet 22d1 made of thermoplastic elastomer or silicone rubber, and the pressing surface 22a2 of each split pressing portion 22a1 protrudes from the elastic sheet 22d1 to the front side. Yes. Further, in this example, a hard resin key operation base 22e is provided between the knob cover 22d and the reinforcing plate 22c, and a pressing hole 22e1 is formed in the key operation base 22e corresponding to each position of the first-stage switch 31a. Each divided pressing portion 22a1 is at least partially located in the pressing hole 22e1 of the key operation base 22e, and a small protrusion 22a3 protrudes from the surface opposite to the pressing surface 22a2, and each small protrusion 22a3. Is in proximity to or in contact with the corresponding first stage switch 31a.

  The peripheral portion 22d2 of the elastic sheet 22d1 is formed in a stepped shape by shifting to the back plate 21c side, and extended portions 22d3 are integrally formed radially outward at a plurality of locations on the peripheral portion 22d2. A receiving piece 22e2 is formed integrally with the extension 22d3 on the back plate 21c side of the circumferential surface of the key operation base 22e. In FIG. 9, the knob cover 22d and the key operation base 22e are shown as separate bodies, but these are integrally formed. Further, the reinforcing plate 22c, the key operation base 22e, and the membrane sheet 31 have the same outer shape as viewed from the direction perpendicular thereto.

In this example, the case 21 is composed of an integral side wall 21d of a hard resin material, and a cover 21a and a back surface plate 21c as surface plates fixed to the surface side end surface and the back surface side end surface of the side wall 21d, respectively. The knob cover 22d, the key operation base 22e, the first-stage press detection part 31a, and the reinforcing plate 22c are fixed to each other to constitute the knob 22.
The front plate 21a is formed by subjecting a metal plate to required processing, and U-shaped locking portions 21a1 having short legs are vertically bent and extended toward the back plate 21c on each side of the square.
The knob cover 22d has a circular top surface outside the opening 21b of the front plate 21a with the elastic sheet 22d1 leaving the peripheral edge portion 22d2, and in this example, five divided pressing portions 22a1 protrude from the top surface. Triangular divided pressing portions 22a1 are provided on the front, rear, left and right sides of the central circular divided pressing portion 22a1, respectively. As shown in FIG. 8, each inner surface of each divided pressing portion 22a1 protrudes to the back plate 21c side from the elastic sheet 22d1, and a small protrusion 22a3 is formed at the center of the protruding end surface. In this example, the divided pressing portion 22a1, the small protrusion 22a3, and the elastic sheet 22d1 are integrally formed of a thermoplastic elastomer, that is, made of a very flexible material.

The key operation base 22e is formed of a hard resin such as ABS resin or polycarbonate, and has a disk shape corresponding to the circular top surface of the knob cover 22d. In the key operation base 22e, a pressing hole 22e1 having the same shape as that of the divided pressing portion 22a1 is formed so as to penetrate in accordance with the position of each divided pressing portion 22a1. In FIG. 9, the key operation base 22e and the knob cover 22d are shown separately. In this example, these are integrally formed, and the elastic sheet 22d1 is fixed to the key operation base 22e without slack.
In this example, the first-stage switch 31a is a case where the membrane sheet 31 including the membrane switch 31a having the same configuration as the membrane switch 23 described with reference to FIG. 5 is used, and is shown in detail in FIGS. However, five membrane switches 31a are formed corresponding to each small protrusion 22a3. In FIG. 8, these first-stage switches (membrane switches) 31a are indicated by blank portions (the same applies to the following).

  The reinforcing plate 22c is made of, for example, a stainless steel plate and has substantially the same shape as the membrane sheet 31. In this example, the switch 23 is formed by integrally forming a membrane switch with the membrane sheet 31 including the first-stage switch 31a, that is, the membrane sheet 23g and the membrane sheet 31 are connected by the connecting portion 31b. A signal lead-out portion (tail portion) 23h is provided on the membrane sheet 31 side, and lead wires for the membrane switches 31a are also formed in the signal lead-out portion 23h. The connecting portion 31b is bent and the membrane sheets 23g and 31 are positioned on both sides of the reinforcing plate 22c.

In this example, the bending member 24 is elastically deformed when the knob 22 is pressed and the switch 23 is operated. When the pressing is released, the bending member 24 is restored to the original shape by the elastic restoring force, and the knob 22 is returned to the original position, and the click feeling is separately provided. The click plate 32 is used. A click plate 32 is provided between the membrane sheet 23 g and the bending member 24. The click plate 32 is made of a spring metal plate and has a dish shape.
The bending member 24 is made of rubber, and a flat plate portion 24a having the same outer shape as that of the case 21 is formed such that the apex of the bending member 24 is located on substantially the same plane and is integrally connected by the peripheral edge of the bending member 24 and the support portion 24b. Yes. As shown in FIG. 8, the support portion 24b is a short one that is obliquely outward from the peripheral edge of the bending member 24 toward the back plate 21c. A protrusion 24 c is provided at the center of the inner surface of the bending member 24. In FIG. 9, the bending member 24 and the case 21 are shown separately, but in this example, they are formed by integral molding.

  The case 21 is made of a hard resin such as ABS resin or polycarbonate, the surface side is open, and it has a shallow rectangular shape with rounded corners. One side of the rectangular side wall 21d slightly protrudes outward, and a notch 21e is formed on the surface side end face. This is an example for configuring the outlet to the outside of the tail part (signal lead part) 23h. Further, in order to connect the side wall 21d of the case 21 and the cover 21a, a pair of small locking projections 21d3 are formed on the outer surface of the side wall 21d, and the outer surfaces of the other three side walls 21d are extended in the side direction. A locking projection 21d3 is formed.

A boss and a hole are formed in each part in order to position and attach each part. A boss 22e3 is formed at the position of each receiving piece 22e2 on the reinforcing plate 22c side of the key operation base 22e, and holes 31c and 22c1 through which these four bosses 22e3 are inserted are respectively formed in the membrane sheet 31 and the reinforcing plate 22c. Four are formed.
Four bosses 24d are formed at 90 ° intervals on the periphery of the bending member 24, and four holes 22c2 through which the bosses 24d are inserted are formed in the reinforcing plate 22c. The membrane sheet 31 and the key operation base 22e are each formed with four holes 31d and 22e4 as reliefs for the boss 24d.

Bosses 21d4 are formed at each corner on the back side of the side wall 21d, and four holes 24a1 and 21c2 through which these four bosses 21d4 are inserted are formed in the flat plate part 24a and the back plate 21c. In this example, the case 21 and the bending member 24 are integrally formed, so that the hole 24a1 of the flat plate portion 24a is a relief with respect to the position of the boss 21d4.
On the other hand, on the surface plate 21a side of the side wall 21d, a boss 21e1 is formed in the notch 21e from which the tail portion 23h is led out, and a hole 31e through which the boss 21c1 is inserted is formed in the membrane sheet 31. . Further, bosses 21d5 are formed at a pair of opposite corners of the side wall 21d on the surface plate 21a side, and a pair of holes 21a2 into which these bosses 21d5 are inserted are formed in the cover (surface plate) 21a. The holes 21a3 formed at the four corners of the cover 21a are used for mounting the two-stage switch unit.

Next, the assembly of the above-described components will be described separately for the assembly of the knob 22, the assembly of the case 21, and the total assembly.
First, the assembly of the knob 22 will be described in order.
(1) The reinforcing plate 22c is fixed to the lower surface of the key operation base 22e which is integrally formed with the knob cover 22d and is arranged on the inner surface of the knob cover 22d and supports the knob cover 22d via the membrane sheet 31. In this fixing, four bosses 22e3 formed on the lower surface of the key operation base 22e are inserted into the four holes 31c of the membrane sheet 31 and the four holes 22c1 of the reinforcing plate 22c, and the tips of these bosses 22e3 are heat caulked. Do by.
(2) The membrane sheet 23g formed integrally with the membrane sheet 31 is bonded and fixed using a double-sided adhesive tape or the like by bending the connecting portion 31b so as to face the lower surface of the reinforcing plate 21c.
(3) On the lower surface of the membrane sheet 23g, the click plate 32 is arranged as a convex downward with its center aligned with the position of the switch contact. The click plate 32 is positioned and fixed to the membrane sheet 23g by covering it with an adhesive tape, for example. Thereby, knob assembly is completed.

The case assembly is performed by arranging and fixing the back plate 21c to the lower surface of the bending member 24 formed integrally with the side wall 21d. This fixing is performed by inserting the four bosses 21d4 of the side wall 21d into the four holes 21c1 of the back plate 21c and thermally crimping the tips of the bosses 21d4.
Next, total assembly will be described.
First, the knob assembly is incorporated into the case assembly. Assembling is performed by inserting the boss 24d of the bending member 24 into the four holes 22c2 provided in the reinforcing plate 22c, and inserting the boss 21e1 of the side wall 21d into the hole 31e of the membrane sheet 31. Is positioned and accommodated in case assembly.

Finally, the cover (surface plate) 21a is attached to complete the assembly, and the two-stage switch unit is completed. The cover 21a is attached by fitting the pair of holes 21a2 into the bosses 21d5 of the side wall 21d and locking the four U-shaped locking portions 21a1 to the locking claws 21d3 of the side wall 21d.
The two-stage switch unit assembled as described above has a structure as shown in FIGS. 7 and 8, and the curved portion 24, the click plate 32, and the membrane sheets 31 and 23 g are sequentially arranged on the back plate 21 c of the case 21. A reinforcing plate 22c held on the upper and lower surfaces and a key operation base 22c integrated with the knob cover 22d are mounted. That is, the reinforcing plate 22c, the membrane switch 31, the key operation base 22e, and the knob cover 22d constitute the knob 22. The knob 22 is pressed against the surface plate 21a by the bending member 24, and the case 22 of the knob 22 is received by the receiving piece 22d2 of the key operation base 22e. 21 and the split pressing portion 22a1 of the knob cover 22d faces the outside through the opening 21b. Note that the click plate 32 is protruded downward on the projection 24c of the bending member 24, and the center thereof is aligned.

As shown in FIG. 8, the size (diameter) of the bending member 24 is set to include the positions of all the small protrusions 22a3 of the divided pressing portion 22a1, and the reinforcing plate 22c is formed by the periphery of the bending member 24b. As described above, it is supported and inserted and positioned by the boss 24d.
The flat plate portion 24a is connected and integrated with the side wall 21d and is located on the back plate 21c.
Next, the operation of the two-stage switch unit having the above configuration will be described.
When lightly pressing one of the arbitrary divided pressing portions 22a1 in the knob 22, for example, the central divided pressing portion, the elastic sheet 22d1 around the divided pressing portion 22a1, that is, the pressing portion hole 22e1 of the elastic sheet 22d1. A portion between the peripheral edge and the divided pressing portion 22a1 bends, and the small protrusion 22a3 is pushed. The membrane switch 31a as the first-stage switch is pressed by the small protrusion 22a3, and the opposing contacts (not shown) come into contact with each other, whereby the first-stage switch 31a is turned on and the pressing is detected.

  Further, when the divided pressing portion 22a1 is pressed, the knob 22 is pushed into the case 21 against the biasing force of the bending member 24, whereby the peripheral portion of the bending member 24 is pressed and the bending member 24 is crushed and deformed. Thus, the projection 24c of the bending member 24 presses the click plate 32 toward the switch 23. The center of the click plate 32 that has been pressed is reversed with respect to the peripheral portion of the click plate 32 with a click feeling (hereinafter, this phenomenon is simply referred to as reversal), and the membrane switch 23 as the second-stage switch is reversed. Pressed by the center of the click plate 32, the membrane switch 23 is turned on when its opposing contacts (not shown) contact each other.

As the pressure is released, the knob 22 returns to the original position by the elastic restoring force of the bending member 24 and the click plate 32, that is, the peripheral edge thereof is pressed against the surface plate 21a, and the second-stage switch 23 is turned off. When the pressing is completely released, the divided pressing portion 22a1 and the small protrusion 22a3 are returned to their original positions by the restoring force of the membrane sheet 31, and the first-stage switch 31a is turned off.
In this example, since the membrane switch 31a as the first-stage switch is located inside the switch unit, the contact point can be formed on a very thin, for example, polyethylene film by a printed wiring technique, and the reaction force is extremely small. can do. Further, by bending only the elastic sheet 22d1 made of a flexible thermoplastic elastomer, the first-stage switch 31a is turned on, so the on-load of the first-stage switch 31a can be extremely reduced. In other words, the key operation surface of the two-stage switch unit is configured such that the knob cover 22d is held by the key operation base 22e, and the key operation surface can be moved by stroking the key operation surface with a finger so that the finger contacts the pressing portion 22a. The stage switch can be turned on. Moreover, the outer shape of the knob cover 22d is maintained by the key operation base 22e, there is no possibility of damage even if it contacts an external object, and the key operation surface is held.

  Further, the small protrusions 22a3 of all the divided pressing portions 22d1 are located on the opening of the bending member 24, the curvature radius of the bending surface of the bending member 24 is large, and the peripheral edge of the bending member 24 is the flat plate portion 24a. Is supported by the support portion 24b positioned on the back plate 21c by the above, so that it is supported stably in parallel with the back plate 21c, and even if the peripheral divided press portion 22a1 is pressed, the bending member 24 is The reaction force received from the face plate 21c is substantially parallel to the center line of the bending member 24, the force in the rotational direction does not substantially act on the bending member 24, and a good stroke feeling (operation feel) is obtained. There is no possibility that the life of the member 24 and the click plate 32 will be shortened, and it is difficult for permanent deformation to occur.

Further, since the key operation base 22e is received by the cover 21a with the receiving piece 22e2, even if the end pressing operation is performed, the opposite side of the key operation base 22e is prevented from moving in the direction opposite to the pressing direction, that is, the key operation base 22e. Therefore, even when the switch 23 at the second stage is pressed, the variation in operation feeling is small. The receiving piece 22e2 is not limited to this example, and may be provided on the entire circumference of the key operation base 22e. In this case, the extension 22d3 of the knob cover 22d is also provided along the entire circumference.
Further, in this example, the click plate 32 has a large diameter, and its opening is sized to include the positions of the small protrusions 22d3 of all the divided pressing portions 22d1 as shown in FIG. Even so, the reaction force of the click plate 32 is obtained on the extended line of the small protrusion 22d3 of the divided pressing portion 22d1, and thus the rotation of the knob 22 is also suppressed in this respect, and the reverse feeling of the click plate 32 is also achieved. Is good, there is no risk of permanent deformation, and the life is extended.

In addition, in this example, the reinforcing plate 22c is supported by the bending member 24, and its four holes 22c2 are inserted and positioned by the four bosses 24d of the bending member 24. There is no backlash in the in-plane direction of the top surface, and the operation feel is also excellent in this respect.
Further, the extension 22d3 of the knob cover 22d is positioned on the receiving piece 22e2 of the key operation base 22e, and the receiving piece 22e2 is configured to abut against the cover 21a via the flexible extension 22d3. A high-quality two-stage switch unit can be provided that can suppress the sound that is generated when the knob 22 that has been pressed and released is restored, and that has a low return sound.

As described above, the large opening of the click plate 32 can reduce the influence of the positional deviation between the protrusion 24c that presses the click plate 32 and the click plate 32. It can be avoided that the displaced portion is pressed to cause permanent deformation and the durability life is shortened.
In this example, a flexible thermoplastic elastomer is used as a constituent material of the knob cover 22d. Alternatively, the knob cover 22d may be formed of, for example, silicon rubber.
In this example, the knob cover 22d and the key operation base 22e are integrally formed, but they may be formed separately. However, by integrally forming the knob cover 22d and the key operation base 22e, each small cover is provided with respect to the lower surface of the key operation base 22e, that is, the switch 31a of the membrane sheet 31 positioned on the lower surface of the key operation base 22e. The positional accuracy (height accuracy) of the protrusion 22d3 can be stabilized, and thereby variation in the operational feeling among the plurality of divided pressing portions 22d1 can be suppressed.

In this example, since the first-stage switch 31a and the second-stage switch 23 are both constituted by the membrane sheets 31, 23g, the thickness and size can be reduced, the number of assembling steps can be reduced, and the cost is low. Can be configured.
[Modification]
As shown in the second embodiment, the bending member 24 is made of rubber, and the click plate 32 can be omitted so that a click feeling can be obtained. A cross section corresponding to FIG. 3 is shown in FIG. The cross section including the center line is a wide isosceles triangle, that is, the apex of the conical skirt portion 24e having a wide opening is a cylindrical top portion 24f having a short axis, and the outer periphery is on the outer side in a plane perpendicular to the center line. An extended flange portion 24g is integrally formed. In this example, the outer end surface of the top portion 24 f is in contact with the back plate 21 c, and the flange portion 24 g is in contact with the inner surface of the knob 22. In this case, the opening diameter of the skirt portion 24e is 0.7 times or more the diameter of the pressing portion 22a.

In this example, a movable contact 23f is formed on the inner end surface of the top 24f, a pair of fixed contacts 23d and 23e are formed on the resin material sheet 23i so as to face the movable contact 23f, and the sheet 23i is attached to the inner surface of the knob 22. The flange portion 24g is brought into contact with the knob 22 via the seat 23i. That is, the switch 23 is a rubber switch.
When the pressing portion 22a of the knob 22 is pressed into the case 21, when the size exceeds a certain level, the skirt portion 24e is elastically deformed and reversed, and the top portion 24f is pressed by the fixed contacts 23d and 23e to be movable. The contact 23f contacts the fixed contacts 23d and 23e, and the switch 23 is turned on. A click feeling is obtained when the skirt portion 24 is reversed. When the pressing is released, the original shape is restored by the elastic restoring force of the bending member 24. The rubber bending member 24 that provides such a click feeling can also be applied to the two-stage switch shown in the second embodiment. Similarly, the switch 23 can be a rubber switch or can be applied to the second embodiment. .

  Further, the bending member 24 may have no click feeling. As an example, FIG. 11 shows a cross section corresponding to FIG. The bending member 24 has a shape of a part of a spherical surface having a large radius, and a flange portion 24g is integrally formed with a peripheral portion thereof, and a protrusion 24c is integrally formed with a rubber on an inner surface of the apex. In this example, a two-stage switch unit is used, and the knob 22 is provided on the reinforcing plate 21c and the surface opposite to the back plate 21c of the reinforcing plate 21c, and a plurality of one-stage switches 31g and a plurality of one-stage switches 31g. This is a case of comprising a knob cover 22d provided on the surface plate 21a side. The reinforcing plate 22c is formed of a hard resin material, a flexible substrate 31g1 is formed on the reinforcing plate 22c, and a fixed contact 31g2 and its wiring are formed on the flexible substrate 31g1 corresponding to each first-stage switch 31g by printed wiring technology. The knob cover 22d is provided via the spacer 31g3.

The knob cover 22d is formed integrally with a split pressing portion 22a1 protruding slightly on one surface of the flexible sheet 22d5 at a position corresponding to each one-stage switch 31g, and is movable in close proximity to the fixed contact 31g2 on the opposite surface. The contact 31g4 and its wiring are formed by a printed wiring technique.
When one divided pressing portion 22a1 is lightly pressed, the flexible sheet 22d5 is bent, the movable contact 31g4 corresponding to the divided pressing portion comes into contact with the fixed contact 31g2, and one switch 31g is turned on.

Although not shown in the drawing, a boss is erected on the reinforcing plate 22c, and the boss is passed through the hole of the flange portion 24g and fixed to each other by heat caulking.
Also in this case, the diameter of the opening is 0.7 times or more the diameter of a circle surrounding all the divided pressing portions 22a1. Further, the protruding end of the protrusion 24c is sharpened in a hemispherical shape so that the membrane switch 23 can be surely pressed. The tail portions of the flexible sheet 22d5, the flexible substrate 31g1, and the membrane sheet 23g are overlapped and led out to the outside.
In this case, when the pressing portion 22a is pressed, the bending member 24 is gradually elastically deformed without being inverted, and the protrusion 24c presses the switch 23. It can be easily understood that this embodiment can also be applied to the first embodiment.

In the above description, the top of the bending member 24 is positioned on the back plate 1c side, but the top may be positioned on the knob side. For example, as shown in FIG. 12 in a cross-section corresponding to FIG. 3, the click plate 24 as a bending member is provided with the opening on the back plate 21c side. The switch 23 is attached to the back plate 21c so as to face the center of the click plate 24 between the bending member 24 and the back plate 21c. The diameter _{D C} of the opening of the click plate 24 is 0.7 times or more the diameter _{D N} of the pressing portion 22a of the knob 22. In this example, a protrusion 22g is integrally formed on the knob 22 so as to face the curved apex of the click plate 24, and the reverse of the click plate 24 is generated with a substantially constant pressing force as much as possible.

In this way, even when the click plate 24 is arranged with the convex side thereof as the knob 22 side, the reaction force received by the click plate 24 due to the pressing of the knob 22 is almost parallel to the center line of the click plate 24. Easy to understand. In addition, the opening side of the bending member 24 as described above can be applied to the second embodiment, and in either case, the bending member 24 may have a click feeling or may not be obtained. Moreover, what used together the bending member 24 and the click board which cannot obtain a click feeling may be used.
13A and 13B show an example in which a part of the divided pressing portion 22a1 and the elastic sheet 22d1 are made of different materials. In FIG. 13A, the divided pressing portion 22a1 and the small protrusion 22d3 are made of hard resin. In FIG. 13B, the upper surface side of the divided pressing portion 22a1 is made of hard resin.

The top view of 1st Embodiment of this invention. FIG. 2 is a cross-sectional view taken along line AA in FIG. 1. The BB sectional view taken on the line in FIG. The disassembled perspective view of 1st Embodiment shown in FIG. FIG. 6 is a cross-sectional view showing a specific example of the switch 23. Sectional drawing corresponding to FIG. 3 which shows the state by which switch operation was carried out with the press switch unit of 1st Embodiment. The top view which shows 2nd Embodiment of this invention. A is a cross-sectional view taken along line AA in FIG. 7, and B is a cross-sectional view taken along line BB in FIG. The disassembled perspective view of 2nd Embodiment shown in FIG. Sectional drawing corresponding to FIG. 3 which shows the other Example of 1st Embodiment. Sectional drawing corresponding to FIG. 8A which shows the other Example of 2nd Embodiment. Sectional drawing corresponding to FIG. 3 which shows the further another Example of 1st Embodiment. Sectional drawing which shows the example which changed the material of the division | segmentation press part of 2nd Embodiment, and an elastic sheet. Sectional drawing which shows the conventional press switch unit. The partially expanded sectional view for demonstrating the problem of the conventional press switch unit.

Claims (6)

A case in which an opening is formed in the surface plate;
A knob provided on the case and facing outside from the opening;
A curved member made of an elastic material, disposed between the knob and the back plate of the case;
Disposed between the back plate of the knob and the case, and a switch which is more operated pressing operations above Symbol knob,
The knob above
A reinforcing plate that is movable in a direction perpendicular to the back plate;
A knob cover provided on the surface plate side of the reinforcing plate and provided with a plurality of divided pressing portions;
A plurality of first-stage press detection units that are provided for each of the divided pressing portions between the knob cover and the reinforcing plate and are operated by a pressure weaker than a reaction force of the bending member against the divided pressing portions;
With
The bending member has an annular peripheral edge that contacts the periphery of the reinforcing plate, and a flat plate that is positioned on the outer peripheral side of the peripheral edge and supports the peripheral edge via a support.
A press switch unit characterized by that. The opening of the bending member has the same size as the entire pressing portion of the knob.
The press switch unit according to claim 1. Between the bending member and the switch, pressing the switch unit according to claim 1 or 2 click member for reversing with a click feeling is central by push pressure operation is characterized in that it is interposed. 4. The press switch unit according to claim 3, wherein the opening of the click member is smaller than the opening of the bending member, but is equal to substantially the entire surface of the pressing portion. The press switch unit according to any one of claims 1 to 4 , wherein a protrusion protruding toward the switch is formed at a central portion of the bending member. The press switch unit according to any one of claims 1 to 5 , wherein the bending member is 0.7 times or more of the pressing portion.

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