JPH0590760U - switch - Google Patents

Abstract

(57) [Abstract] [Purpose] We propose a switch that can be supplied at a low price by reducing the number of parts, downsizing. A cover 7 is fitted on a space of a box-shaped body 1 having a pair of fixed terminals 5 and 6, a coil spring 12 is housed in the body 1, and a lower end portion of the coil spring 12 is a fixed terminal at all times. 5, the bent portion (contact portion) 12a of the coil spring 12 is in contact with the contact portion 5b of the actuator 1.
When pushing down 3, the contact portion 6b of the fixed terminal 6 is contacted by the twisting force of the coil spring 12.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a switch suitable for application to detection of a hole or a recess formed in a cassette of a camcorder or a case of an optical mini disk, which is used for preventing accidental erasure or malfunction.

[0002]

[Prior Art]

 A switch shown in Japanese Utility Model Publication No. 57-17698 has been proposed as this type of switch. This will be briefly described with reference to FIG. 6A. A pair of terminals 22a and 22b are provided on the bottom wall of the insulating case 21, and a pair of terminals 22a and 22b are normally short-circuited (ON) by a coil spring 24 that pushes the push button 23 upward. By pushing down the push button 24, as shown in FIG. 6B, the terminal 22b is pushed and bent, and is separated from the coil spring 24, so that the pair of terminals 22a and 22b is turned off.

As shown in FIG. 7B, the one disclosed in Japanese Utility Model Laid-Open No. 1-132025 is provided with a pair of terminals 26a and 26b on the inner surfaces of the left and right walls of the insulating body 25, and the coil spring 27 shown in FIG. A movable contact piece 29 is attached to the push button 28 that is biased upward, and when the push button 28 is pressed down, the movable contact piece 29 is configured to interrupt between the pair of terminals 26a and 26b to turn them on.

[0004]

[Problems to be solved by the device]

 In the former switch, the curved portion of the terminal 22b is bent and stretched every time the push button 23 is operated, and the force is intensively applied to the curved portion, so that there is a problem that the durability of this portion deteriorates during long-term use. In addition, the latter switch has a problem that the number of parts such as the movable contact piece 29 increases and this hinders downsizing of the entire switch. This device proposes a switch that avoids these problems.

[0005]

In order to solve the above problems, in the present invention, a bottom wall 2 and four side walls 3a to 3d are provided, and a pair of fixed terminals 5 and 6 are attached so as to be insulated from each other. The box-shaped body 1 that has been led out to the above, the cover 7 that covers the space of the body 1 and is fitted to the body, and the through hole 10 formed in the cover 7 so as to be slidably penetrated. It is composed of an actuator 13 and a coil spring 12 housed in the body 1 and constantly pressing the actuator 13 outward. One fixed terminal 5 is arranged along the inner surface of the side wall 3c of the body 1 or the bottom wall 2. The other fixed terminal 6 is arranged along the inner surface of the side wall 3a of the body 1, and when the coil spring 12 is housed in the body 1, both ends 12a and 12b of the coil spring 12 are twisted by the torsional force. 1 is pressed against the inner surfaces of the opposite side walls 3a and 3c, one end 12b or a portion in the vicinity thereof is constantly in contact with one fixed terminal 5, and the other end 12a is connected to the other fixed terminal 6 with respect to the actuator 13 It is configured to make contact within a predetermined movement range of.

[0006]

[Action]

 According to this invention, the coil spring 12 itself also serves as a movable contact, the number of parts is gradually reduced, and the size can be reduced. Part) 12a and the contact part 6b of the fixed terminal 6 are brought into contact with each other, and a good contact state can be obtained without the need for a movable contact piece.

[0007]

【Example】

 An example of the switch according to the present invention will be described with reference to FIGS. As is apparent from FIG. 2, the body 1 is composed of a bottom wall 2 and four side walls 3a to 3d in a box shape, and a pair of protrusions having a downward wall thickness on the outer surfaces of the side walls 3a and 3c. 4a and 4b are formed. A pair of strip-shaped fixed terminals 5 and 6 are embedded in the bottom wall 2, one end of each of which is led out of the body 1 to serve as lead-out portions 5a and 6a, and the other ends of which are inside the body 1. To be contact portions 5b and 6b. The body 1 is formed by resin injection molding or the like with the fixed terminals 5 and 6 inserted in the mold.

As shown in FIG. 3C, the bottom surfaces of the lead-out portions 5 a, 6 a of the fixed terminals 5, 6 are located in the same plane as the bottom surface of the bottom wall 2 of the body 1, and the fixed terminals 5 are arranged above the contact portions 5 b thereof. The surface is bent in the bottom wall 2 so as to be substantially flush with the upper surface of the bottom wall 2 of the body 1 and exposed inside the body 1. Further, a raised portion is partially formed on this exposed surface, which will be described later. It is a contact portion 5c with the coil spring.

The fixed terminal 6 is bent inside the bottom wall 2 of the body 1 along the strip-shaped plate surface that constitutes the fixed terminal 6 into an L-shape (see FIG. 3B). Is bent upward along the side wall 3a of the body 1 (see FIG. 3A), and the upward bent portion is selected to be the same as the inner surface of the side wall 3a of the body 1, that is, exposed inside the body 1 6b.

A cover 7 is fitted on the upper surface of the body 1. As shown in FIG. 2, the cover 7 includes a lid portion 8 for covering the space of the body 1 and a pair of mounting pieces 9a, 9b extending continuously downward from both shoulders of the lid portion 8. The cover 8 is formed with a through hole 10 and the mounting pieces 9a and 9b are formed with grooves 11a and 11b downward from their shoulders, respectively. When fitted from above, the lower edges of the grooves 11a and 11b are engaged with the lower ends of the protrusions 4a and 4b of the body 1 and the cover 7 is fitted onto the body 1. The cover 7 shown in this example is configured so that the two bodies 1 described above can be connected to each other. In FIG. 2, the right side mounting piece 9b of the left side cover 7 and the left side mounting piece 9a of the right side cover 7 are integrated. It shows the case of being formed.

A coil spring 12 is housed in the body 1. As shown in FIGS. 4A and 4B, the coil spring 12 is formed by winding a wire having elasticity into a coil shape, and in a state of being manufactured, that is, before being housed in the body 1, as shown in FIG. The openings at their ends, viewed, are chosen to have an angle θa. Further, both ends thereof are bent inwardly in a dogleg shape to form bent portions 12a and 12b, respectively, and the bent portion 12a at the upper end is a contact portion with the contact 6b described above.

In order to store the coil spring 12 in the body 1, an external forcing force that makes the angle θa sufficiently small is applied against the twisting force (the force that causes the coil winding to return to its original position). It is stored in the state, and the force is released inside the body 1. As a result, the opening angle θb of the coil spring 12 (see FIG. 3B) becomes smaller than θa at the time of manufacturing (θa> θb), and the bent portion 12a of the coil spring 12 is located on the inner surface (upward) of the left side wall 3a of the body 1. The bent portion 12b is pressed against the inner surface (downward) of the right side wall 3c by the twisting force of the coil spring 12, respectively. In this state, the lower end portion of the coil spring 12 is in contact with the contact portion 5b of the fixed terminal 5. The contact portion 5b may extend in a direction orthogonal to the lead-out portion 5a as shown in FIG. 3B.

The cover 7 is fitted to the body 1 with the actuator 13 penetrating through the through hole 10, and the actuator 13 is always outward due to the restoring force of the coil spring 12 in the body 1 in the axial direction (winding direction). Pressed (upward). The actuator 13 has a cylindrical shape, its head is formed in a hemispherical shape, and the lower part thereof has a plate portion 14 formed in a substantially quadrangular shape so as to be inserted into the body 1, as shown in FIG. A column portion 15 formed on the lower surface of the plate portion 14 and a meat pressure portion 16 formed in almost half of the plate portion 14 are formed, and between the meat pressure portion 16 and the cylinder portion 15. An arcuate groove 17 is formed. The latter half of the circular portion of the upper end of the coil spring 12 is inserted and fitted into the arc-shaped groove 17 (see FIG. 4B), and the actuator 13 is always biased upward.

According to this configuration, the lower end portion of the coil spring 12 is always in contact with the contact portion 5b of the fixed terminal 5, and the bent portion 12a at the upper end portion is the inner surface of the side wall 3a at all times (states of FIGS. 3A and 3C). Touches (upper). Therefore, the fixed terminals 5 and 6 are not always short-circuited and are in the off state. When the actuator 13 is pushed down from this state, the bent portion (contact portion) 12a of the coil spring 12 slides and descends on the inner surface of the side wall 3a, and the contact portion 6b of the fixed terminal 6 is lowered at the La lowered position shown in FIG. 3A. , And the contact state continues below that, and the fixed terminals 5 and 6 are short-circuited (ON). When the pressing of the actuator 13 is stopped, the actuator 13 returns to its original state due to the elasticity of the coil spring 12, the contact of the bent portion 12a of the coil spring 12 with the contact portion 6b is released, and the fixed terminals 5 and 6 are separated from each other. Turns off.

In the above description, the contact portion 6b is exposed inside the body 1 at the lower half of the side wall 3a of the body 1. On the contrary, as shown in FIG. 3D, it is exposed at the upper half of the side wall 3a. It may be configured as follows. In this case, the fixed terminals 5 and 6 are short-circuited (on) in a steady state where the actuator 13 is not pushed down, and it is turned off when the actuator 13 is pushed down. Furthermore, as shown in FIG. 3E, the bent portion 12a of the coil spring 12 may contact the contact portion 6b only while the actuator 13 is being pushed down, and the actuator 13 may not contact at the steady position and the full stroke state. it can.

Further, the contact portion 5b of the fixed terminal 5 is not limited to the above example, but rises along the inner surface of the side wall 3c as shown by reference numeral 5d in FIG. 3B, so that the bent portion 12b of the coil spring 12 comes into contact therewith. You may comprise. Further, although the case where two bodies 1 are connected has been described, the present invention is not limited to this, and it is also possible to use a single body, or three or more pieces may be connected.

[0017]

[Effect of the device]

 The switch according to the present invention includes the body 1, the cover 7, the coil spring 12 and the actuator 13, and has an effect that it can be configured with a small number of parts. Moreover, only the coil spring 12 and the lower part of the actuator 13 are housed in the body 1, and the coil spring 12 itself also serves as the movable contact piece (movable terminal) conventionally required, so that the size of the entire switch is small. There is an effect that it can be realized, and there is an effect that this switch can be supplied at a low price. Further, since the contact portion 12a and the contact portion 6b of the fixed terminal 6 are brought into contact with each other by the twisting force of the coil spring 12, there is an effect that a good contact state can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a switch according to the present invention.

FIG. 2 is a perspective view of the switch shown in FIG. 1 in an exploded state.

3A is a front view in which a part of the switch shown in FIG. 1 is shown as a cross section, B is a top view with a cover removed, and C is a cross section taken along the line AA of FIG. 3A. , D and E are cross-sectional views of a state in which a part of the configuration shown in FIG. 3A is changed.

FIG. 4A is a front view showing a coil spring before being housed in a body, and B is a top view thereof.

FIG. 5 is a perspective view showing an example of an actuator that can be used in the present invention.

FIG. 6A is a sectional view showing an example of a conventional switch, and B is a sectional view showing its operating state.

FIG. 7A is a perspective view of another example of a conventional switch in an exploded state, and B is a partial cross-sectional view thereof.

Claims (1)

[Scope of utility model registration request] 1. A box-shaped body, which is composed of a bottom wall and four side walls, has a pair of fixed terminals that are insulated from each other and is attached to the outside, and is fitted to the body by covering a space in the body. The cover is attached, an actuator slidably penetrated through a through hole formed in the cover, and a coil spring housed in the body and constantly pressing the actuator outward. One of the fixed terminals is arranged along one of the opposite side walls of the body or the inner surface of the bottom wall, and the other of the pair of fixed terminals is formed along the inner surface of the other side wall of the opposite side walls of the body. The coil spring is disposed in the body, and both ends of the coil spring are pressed against the inner surfaces of the opposite side walls of the body by a torsional force of the coil spring. A switch characterized in that one end thereof is always in contact with the one fixed terminal and the other end is in contact with the other fixed terminal within a predetermined movement range of the actuator.