JP2766438B2 - Push button switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small push button switch suitable for taping packaging and automatic mounting.

[0002]

2. Description of the Related Art Generally, a push button switch of this type is derived from an insulating case made of synthetic resin molded into a bottomed cylindrical shape, a pair of fixed contacts exposed on the inner bottom surface of the insulating case, and each fixed contact. And a pair of terminals protruding outward from the insulating case, and a movable contact that comes into contact with and separate from the fixed contacts in the insulating case, and a pair of strip-shaped metal plates extending parallel to each other are formed when the insulating case is formed. Insert it in the mold,
By cutting or bending each band-shaped metal plate after molding, a part of each band-shaped metal plate is formed as a fixed contact and a terminal. Then, when a pressing operation force is applied to the movable contact facing the inner bottom surface of the insulating case and the movable contact is brought into contact with both fixed contacts, both fixed contacts are conducted through the movable contact and switched to a switch-on state. When the operating force is removed, the movable contact automatically returns to the initial position and returns to the switch-off state. As a specific example for realizing such a configuration with a small number of parts, the movable contact is formed into a substantially bowl shape. 2. Description of the Related Art There is widely known a push button switch in which a movable contact is provided on a ceiling surface of a rubber member and an elastically deformable rubber contact is used, and a top portion of the rubber contact is pressed and driven. Also, pushbutton switches that use a reversing spring as a movable contact and that press the reversing spring with a stem have been widely used.

[0003] Such a small push button switch is shown in FIG.
As shown in (1) above, a large number of units can be efficiently stored and stored in a lump and can be easily supplied to an automatic mounting machine. That is, in the same figure, each push button switch which is taped and wrapped in a line at a predetermined interval has a terminal 2 protruding downward from the insulating case 1 in a long carrier tape made of cardboard or the like. 3, and the carrier tape 3 is folded in a zigzag manner, whereby a large number of pushbutton switches can be efficiently stored and stored in a component storage case (not shown). When mounting on a printed circuit board, the push button switch is taken out of the component storage case and supplied to the automatic mounting machine while being taped and packaged. First, the terminal 2 is cut at a chain line position in FIG. 12 using a lead cutter (not shown). By doing so, the push button switch is separated from the carrier tape 3,
Next, as shown in FIG. 13, the tip of the terminal 2 is brought into contact with the tip surface of the lead guide pin 7 inserted into the terminal mounting hole 6 of the printed circuit board 5 to move the lead guide pin 7 downward. Then, the terminal 2 is inserted into a predetermined terminal mounting hole 6, and thereafter, the terminal 2 is cut and bent by using a cut / clinch blade (not shown). Position. Reference numeral 4 in the drawing denotes a substantially round rubber contact incorporated in each push button switch. A movable contact (not shown) is provided on the ceiling surface of the rubber contact 4 and the inside of the insulating case 1 A fixed contact (not shown) is provided at a position facing the movable contact on the bottom surface.

[0004]

When the push button switch of this type is cut off from the carrier tape 3 or attached to the printed circuit board 5, the terminal 2 is connected to the terminal 2 using a lead cutter or a cut / clinch blade as described above. At this time, the terminal 2 made of a strip-shaped metal plate cannot be cut unless a relatively large shearing force is applied.
In the cutting step, the blade is worn abruptly, in other words, the life of the blade is short, and this has caused a cost increase of the push button switch.

Therefore, it is conceivable to use a round wire or each wire that is easy to cut in place of the strip-shaped metal plate as the metal member that forms the fixed contact and the terminal. However, an ordinary wire is inserted to form an insulating case. However, it is difficult to secure high reliability because sufficient strength cannot be obtained, and the wire may be turned or pulled out of the insulating case.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the prior art, and an object thereof is to provide a highly reliable push-button switch in which abrasion of a terminal cutting blade is suppressed and material cost can be reduced. is there.

[0007]

A first means of the present invention is as follows.
An insulating case made of a synthetic resin material, a fixed contact formed by exposing a part of a metal member inserted at the time of molding the insulating case to an inner bottom surface of the insulating case, and insulating the other part of the metal member by the insulating member In a push button switch including a terminal protruding outside the case and a movable contact that comes into contact with and separates from the fixed contact in the insulating case, a wire material partially crushed as the metal member is used. The crushed portion of the wire is buried in the insulating case.

A second means of the present invention is to provide an insulating case made of a synthetic resin and another part of a metal member inserted into a cavity of a mold at the time of molding the insulating case on an inner bottom surface of the insulating case. A fixed contact that is exposed; a terminal in which a part of the metal member is protruded outside the insulating case; and a movable contact that is incorporated into the insulating case and that can be separated from and connected to the fixed contact. In the push-button switch, a wire is used as the metal member, and a concave portion to be embedded in the insulating case is provided on the back side of the fixed contact surface.

[0009]

According to the above-mentioned means, the wire can be cut with a relatively small shearing force, so that the wear of the blade for cutting the terminal is suppressed, and the use of the wire reduces the material cost.
If the crushed portion of the wire is buried in the insulating case, the wire can be prevented from turning and coming off.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. Here, FIG. 1 is a plan view showing a manufacturing process of the push button switch according to the embodiment, FIG. 2 is a cross-sectional view along the line AA in FIG. 1, and FIG. 3 is a side view showing a completed state of the push button switch. 4 and 5 described above are denoted by the same reference numerals.

In FIGS. 1 to 3, an insulating case 1 of a push button switch is formed by molding a synthetic resin material into a substantially cylindrical shape with a bottom. When the insulating case 1 is formed, a predetermined position is previously crushed. The two wire rods 8 placed in parallel are inserted in a mold in parallel, and after molding, the terminal forming portions 8a of the respective wire rods 8 protruding outward from the insulating case 1 are bent at substantially right angles to remove unnecessary portions. By cutting 8b,
A fixed contact 9 and a terminal 2 are obtained from each wire 8,
The crushed portion 8c of each wire 8 is the bottom plate 1a of the insulating case 1.
Buried inside. That is, in the completed push button switch, a portion of each wire 8 exposed on the inner bottom surface of the insulating case 1 becomes the fixed contact 9 and the insulating case 1
The portion protruding outward is the terminal 2, and the remaining portion of each wire 8 including the crushed portion 8 c is embedded in the bottom plate 1 a of the insulating case 1. A substantially round rubber contact 4 is provided on the inner wall of the insulating case 1.
An annular groove 1b for inserting the annular bottom portion and an air escape groove 1c for eliminating a pressure difference between the inside and the outside of the rubber contact 4 are provided on the ceiling surface of the rubber contact 4 facing the pair of fixed contacts 9. Is provided with a movable contact (not shown).

In this embodiment, the wire 8 is
Since a hoop-shaped round wire whose surface is covered with silver is used, good conductivity of the fixed contact 9 and the terminal 2 is guaranteed, and a large number of insulating cases 1 are connected until they are taken out of a molding die. By doing so, insert molding can be performed efficiently. In this embodiment, the crushing portion 8c is formed by performing a crushing process so that the diameter of each wire 8 becomes approximately half.

As described above, a large number of the push button switches completed in the parts storage case are taped and wrapped in a line at predetermined intervals, and the long carrier tapes carrying the terminals 2 are spelled and folded. Can be stored. Also,
At the time of mounting on a printed circuit board, the push button switch is taken out of the component storage case while being taped and packaged, and supplied to the automatic mounting machine.First, the push button switch is separated from the carrier tape by cutting the terminal 2 using a lead cutter, and then. The tip of the terminal 2 is brought into contact with the tip surface of the lead guide pin to guide the terminal 2 to the terminal mounting hole of the printed circuit board. Thereafter, the terminal 2 is cut and bent by using a cut / clinch blade, whereby the push button switch is pressed. Can be automatically mounted at a predetermined position on a printed circuit board.

When the fixed contact 9 and the terminal 2 of the push button switch are formed using the wire 8 as in the above embodiment,
As compared with the conventional product in which the fixed contact and the terminal are formed by processing a strip-shaped metal plate, the material cost is reduced and the processing is easy, and the wire 8 can be cut with a relatively small shearing force. The wear of the blades (lead cutters and cut / clinch blades) is suppressed and the life thereof is extended, so that the manufacturing cost of the push button switch can be greatly reduced.

Further, as in the above embodiment, a crushed portion 8c is formed in the wire 8 in advance, and the crushed portion 8c is embedded in the bottom plate portion 1a of the insulating case 1 by insert molding. Since the synthetic resin material filled in the periphery strongly restricts the movement of the wire 8 in the bottom plate portion 1a, the wire 8 is firmly fixed to the insulating case 1, so that even if it is a round wire, it is sufficiently attached. Strength is obtained. That is, in each wire 8, the squeezed portion 8c is buried in the insulating case 1 to enhance the detent effect and the detent effect, thereby ensuring reliability.

Next, a second embodiment of the present invention will be described with reference to FIGS.
The description will be made based on FIG.

FIG. 4 is a cross-sectional view of the push-button switch, FIG. 5 is a cross-sectional view of the push-button switch viewed from a different direction from FIG. 4, and FIG. FIG. 7 is a perspective view of the fixed mold of the mold as viewed obliquely from above, FIG. 8 is a perspective view of a main part of a round wire as a component of the push button switch, and FIG. 9 is an insert of the push button switch. FIG. 10 is an explanatory view showing a state in which the mold is completely clamped in the molding step, FIG. 10 is an explanatory view showing a state in which the cavity is filled with the molten resin in the molding step, and FIG. 11 is a state in which the mold is opened in the molding step. FIG.

The push-button switch shown in FIGS. 4 and 5 has a synthetic resin insulating case 11 formed in a substantially cylindrical shape with a bottom.
A pair of fixed contacts 12, 12 exposed on the inner bottom surface 11a of the insulating case 11,
It comprises a terminal 13 projecting outward from the insulating case 11 and a rubber contact 14 which is incorporated into the bottom of the insulating case 11 and which can be brought into contact with and separated from the fixed contacts 12 and 12 and has conductive rubber inside. The base material of the fixed contact 12 and the terminal 13 in a conductive relationship is a single round wire having a good adhesion to the insulating case 11 at a predetermined position, and a total of two round wires 17, 17 are connected to the insulating case 11. It is used in a partially buried state. That is, two wires 1 extending parallel to each other
The recesses 1 and 7 are respectively formed by crushing processing.
7a, 17a are formed and these round wires 17, 17
Into the cavity of the mold and insert the insulating case 11
Are formed, the recesses 17a, 17a are buried in the insulating case 11, so that these round wires are
It is hard to turn and hard to come off. In addition, round wire 17
Is coated with silver.

When the operator pushes down a key top (not shown) downward, the rubber contact 14 facing the inner bottom surface 11a of the insulating case 11 receives a pressing driving force and moves downward. Move to both fixed contacts 1
Since the two fixed contacts 12 and 12 are in contact with each other via the rubber contact 14, the two fixed contacts 12 and 12 are turned on to switch on. Further, when the pushing operation force against the rubber contact 14 is removed in the switch-on state, the rubber contact 14 returns to its original position due to its own elasticity, so that the conduction of the two fixed contacts 12, 12 is released and the switch is switched to the switch-off state. .

Next, a method of manufacturing the above push button switch will be described. The insulating case 11 of the push button switch is formed by inserting a round wire 17 into a cavity 20 using a mold formed by combining a movable mold 18 shown in FIG. 6 and a fixed mold 19 shown in FIG. By inserting a movable pin 22 that can move up and down in accordance with the movement of the slide cam 21 into the center of the fixed mold, the round wire 17 is moved to the position shown in FIG. It is designed to be crushed as shown.

That is, first, as shown in FIG. 9, the round wire 17 is inserted into the cavity 20 into which the movable pin 22 has penetrated, and the mold is clamped. 22a and recess 18 of movable mold 18
The recessed portion 17a is formed by crushing the portion sandwiched between the recesses 17a and 17a.

Next, as shown in FIG. 10, the slide cam 21 is moved in the direction of arrow A to move the movable pin 22 out of the cavity 20, and then the cavity 20 is filled with a molten resin 23 and cooled and solidified. By doing so, a resin is formed around the concave portion 17a.

Thereafter, as shown in FIG. 11, the mold is opened and the hoop-shaped wire 17 is fed by a predetermined amount, so that the insulating case 11 is transferred out of the mold and the slide cam 21 is moved in the direction of arrow B. The unprocessed round wire 1 is moved between the movable pin 22 and
Since 7 is arranged, insert molding can be performed continuously by repeating the above operation. Note that reference numeral 1 in FIG.
Reference numeral 5 denotes a known eject pin used for opening the mold.

When the insulating case 11 has been transferred to a predetermined position in this way, the rubber contact 14 is incorporated into the insulating case 11 and the upper end 16 around the rubber contact 14 is brought into contact with the ridge 11 of the case 11.
b, the movable contact is fixed to the case, and the round wire 17 protruding outward from the insulating case 11 is cut or bent to form the terminal 13, thereby forming a push button switch as shown in FIG. .

Then, the completed push button switch is taped and wrapped with a carrier tape, and is chucked by an automatic mounting machine at the time of mounting and separated from the carrier tape, so that automatic mounting at a predetermined position on a printed circuit board can be easily performed.

As described above, in the above embodiment, the round wire 17
, The strength of the round wire 17 against the insulating case 11 against the rotation and the strength of the stopper against the insulating case 11 are significantly increased. Therefore, high reliability is achieved despite the use of an inexpensive round wire. Is secured.

In the second embodiment of the present invention, the round wire 1
Although the recesses 17a, 17a are provided on the back surface of the fixed contact 12 in FIG. 7, this is an example, and other shapes may be used as long as the recesses are provided so as to be embedded in the case.

In the first and second embodiments, the push-button switch incorporating the rubber contact functioning as a movable contact and an actuating body has been described. It is needless to say that the present invention is also applicable to the pushbutton switch of the above type.

Although a round wire is used as the wire 8 in the first and second embodiments, substantially the same effect can be expected by using a square wire.

[0030]

As described above, according to the present invention in which the wire is used as the base material of the fixed contact and the terminal and the crushed portion of the wire is buried in the insulating case, the wire is used instead of the strip-shaped metal plate. As a result, the material cost can be reduced, the wear of the blade for cutting the terminal is also suppressed, and the synthetic resin material filled around the above-mentioned crushed part firmly fixes the wire, so reliability due to insufficient mounting strength Deterioration can be prevented,
It has various excellent effects.

[Brief description of the drawings]

FIG. 1 is a plan view showing a manufacturing process of a push button switch according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a side view showing a completed state of the push button switch.

FIG. 4 is a sectional view of a push-button switch according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view of the push button switch viewed from a direction different from that of FIG. 4;

FIG. 6 is a perspective view of the movable mold of the mold used at the time of insert molding of the push button switch, as viewed obliquely from below.

FIG. 7 is a perspective view of a fixed mold seen from obliquely above.

FIG. 8 is a perspective view of a main part of a round wire as a component of the push button switch.

FIG. 9 is an explanatory view showing a state in which mold clamping of a mold is completed in an insert molding step of a push button switch.

FIG. 10 is an explanatory view showing a state in which a cavity is filled with a molten resin in a molding step.

FIG. 11 is an explanatory view showing a state where a mold is opened in a molding step.

FIG. 12 is a side view for explaining taping packaging of a conventional push button switch.

FIG. 13 is a partial cross-sectional side view for explaining a mounting operation of a conventional push button switch.

[Explanation of symbols]

 1,11 ... insulating case 9,12 ... fixed contact 8,13 ... terminal 4,14 ... rubber contact 8c, 17a ... crushed part (recess)

Continuation of the front page (56) References JP-A-1-112619 (JP, A) JP-A-3-77216 (JP, A) JP-A-3-212997 (JP, A) JP-A-4-19926 (JP) JP-A-5-261822 (JP, A) JP-A-5-48148 (JP, U) (58) Fields studied (Int. Cl. ⁶ , DB name) H01H 13/00-13/76 H01H 11/00-11/06

Claims (2)

(57) [Claims] 1. An insulating case made of a synthetic resin material, a fixed contact made by exposing a part of a metal member inserted at the time of molding the insulating case to an inner bottom surface of the insulating case, In a push button switch including a terminal part of which protrudes outward from the insulating case and a movable contact which comes into contact with and separates from the fixed contact within the insulating case, a part of the push button switch is crushed as the metal member. Using the wire rod
A push button switch, wherein the crushed portion of the wire is buried in the insulating case. 2. An insulating case made of a synthetic resin, a fixed contact formed by exposing a part of a metal member inserted into a cavity of a mold at the time of molding the insulating case to an inner bottom surface of the insulating case, A push button switch including a terminal formed by projecting another part of the metal member outward from the insulating case, and a movable contact incorporated in the insulating case and capable of moving toward and away from the fixed contact; A push button switch characterized in that a recess is provided on the back side of the fixed contact surface, the recess being embedded in an insulating case.