JPH02982Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a snap switch that is used by being incorporated into the mechanism of a tape recorder, for example, and is particularly intended to provide a snap switch that has a simplified structure and can be manufactured at low cost.

<Conventional Description> Fig. 1 shows a conventional snap switch. This snap switch is also called a skeleton switch, and when a movable mechanism (not particularly shown) of a tape recorder, for example, engages with a resin piece 1b constituting the operating lever 1 and rotates the operating lever 1 in the direction of the arrow 2, the movable contact 3 performs the operation of switching from fixed contact 4 to 5, and this switching is used, for example, to switch the tape drive direction or to switch the recording and reproducing circuits.

The operating lever 1 is composed of a spring piece 1a whose one end is supported by an insulating body 6, and an insulating resin piece 1b attached to the free end of this spring 1a.

The switch consists of a movable contact piece 7 whose one end is supported by an insulating body 6, fixed contact pieces 8 and 9, a movable contact 3 attached to the free end side of the movable contact piece 7, and each loose member of the fixed contact pieces 8 and 9. It is composed of fixed contacts 4 and 5 attached to the ends, and a biasing spring 11 attached between the operating lever 1 and the free end of the movable contact piece 7.

The biasing spring 11 has the function of pressing the movable contact 3 against the fixed contact 4 when the operating lever 1 is not operated, and the direction of the biasing force of the biasing spring 11 is reversed when the operating lever 1 is rotated in the direction of arrow 2. It has a function of bringing the movable contact 3 into contact with the fixed contact 4 and the fixed contact 5. This reversal action is generally referred to as a snap action, and this snap action increases the speed at which the movable contact 3 separates from the fixed contact 4, thereby suppressing arcing and preventing deterioration of the contact.

<Conventional disadvantages> According to the conventional snap switch shown in FIG.
and a biasing spring 11 are required. For this reason, there are disadvantages that the number of parts increases, the structure becomes complicated, and the cost increases because assembly is troublesome.

Further, the amount of rotation of the operating lever 1 is limited at the position where the biasing spring 11 abuts against the insulating body 6. For this reason, the amount of movement of the mechanism for operating the operating lever 1 must be limited, and this has to be taken into consideration when designing the mechanism, resulting in a disadvantage that the design becomes complicated.

Furthermore, in the state where the movable contact 3 is switched to the fixed contact 5, the contact pressure between the movable contact 3 and the fixed contact 5 is only applied from the biasing spring 11, and even if the amount of rotation of the operating lever 1 increases, the contact pressure increases. do not.
Therefore, in order to increase the contact pressure, the biasing force of the biasing spring 11 must be increased. If the biasing force of the biasing spring 11 is large, the operating force that must be applied to the operating lever 1 becomes large, which also has the drawback of increasing the burden on the mechanism that operates the switch.

Furthermore, since the biasing spring 11 must be installed between the movable contact piece 7 and the operating lever 1 during assembly, there is also a drawback that the assembly cannot be automated.

<Purpose of the invention> The purpose of this invention is to provide a snap switch that has a simple structure, can be manufactured at low cost, is easy to assemble, and can be automated.

<Summary of the invention> In this invention, the leaf spring constituting the operating lever is made to have a flat spring, a tongue piece is formed in the part that has this flat spring, and a movable contact is provided at the free end of this tongue piece, so that the operating lever can be moved. When the tongue is rotated, the tongue piece snaps due to the force exerted on the leaf spring, and the contact is switched by this snapping action.

Therefore, according to this invention, the biasing spring 11 shown in FIG. 1 is not required, and the leaf spring 1a constituting the operating lever 1 can be used in common with the movable contact piece 7, so that the number of parts can be reduced. .

FIG. 2 shows an embodiment of this invention. 1st in the diagram
Parts corresponding to those in the drawings are given the same reference numerals, and redundant explanation thereof will be omitted, but in this invention, a movable contact piece is integrally molded on the leaf spring 1a that constitutes the operating lever 1, and furthermore, the operating lever 1 is constructed. The leaf spring is provided with a flat spring, and the free end of the tongue piece, which operates as a movable contact piece, is configured to snap into action.

In other words, the operating lever 1 shown in FIG. 2 is composed of a leaf spring 1a whose one end is supported by the insulating body 6, and a resin piece 1b attached to the free end of the leaf spring 1a. However, in this invention, a tongue piece 12 protruding from the operating section side is formed on the leaf spring 1a as shown in FIG. 3, a movable contact 3 is attached to the free end of this tongue piece 12, Tongue piece 12
The structure is such that it is used as a movable contact piece.

In this example, as shown in FIG. 3, the leaf spring 1a has a rectangular frame-shaped portion 13 formed at its center, and a support portion 14 that is held by the insulating body 6 is formed protruding from one end of this frame-shaped portion 13. It has a structure in which an operating part 15 for attaching the resin piece 1b is formed protrudingly on the other end side,
The tongue piece 12 is formed to extend in the protruding direction of the support part 14 from the side where the operation part 15 is formed to protrude inside the frame part 13, and further, the tongue piece 12 is formed to extend in the direction of protrusion of the support part 14 from the side where the operating part 15 is formed to protrude from the inside of the frame part 13. Fold it downward as shown in Figure 4. By this bending, the frame-shaped portion 13
It is possible to give it a peco-like character.

When the support part 14 is fixed and the operating part 15 is pressed downward due to this flatness, the frame-shaped part 13 is curved, but when the frame-shaped part 13 is bent to a certain extent, the free end of the tongue piece 12 is suddenly bent due to the flatness. be thrown upwards. This invention attempts to utilize the movement of this tongue piece 12 as a movable contact piece of a snap switch.

That is, the support part 14 is supported by the insulating body 6 as shown in FIG. 2, and the resin piece 1b is attached to the operating part 15. A claw 17 formed on the operating portion 15 is a claw for locking the resin piece 1b. The resin piece 1b attached to the operating part 15 is pressed against the stopper 18 projected from the insulating body 6 and the tip 22 of the support plate 21 due to the spring properties of the leaf spring 1a, and is held in a so-called preloaded state.

Two protrusions 19 are further formed protruding from the insulating body 6 along the leaf spring 1a at a distance corresponding to the width of the frame of the frame-shaped portion 13, and the tips of the two protrusions 19 are attached to the respective leaf springs. Frame-shaped portion 13 formed in 1a
Abut on approximately the center of the longitudinal direction.

This contact position is selected to correspond to the tip of the tongue piece 12.

The free end of the fixed contact piece 8 is provided at a position opposite to the movable contact 3 attached to the free end of the tongue piece 12, and the fixed contact 5 is formed on this free end by, for example, bending.
In this example, a fixed contact on the normally closed side is not provided, but a fixed contact piece is arranged within the opposing interval between the two protrusions 19, and the free end of the tongue piece 12 is always connected to the free end portion of this fixed contact piece. It is also possible to make a switch with a normally closed contact.

The distal end side of the resin piece 1b constituting the operating lever 1 engages with the distal end portion 22 of two support plates 21 formed parallel to the protrusion 19 from the insulating body 6, and the resin piece 1b
The structure is such that it does not swing due to vibrations, etc.

Also, a pair of round holes 2 formed in the insulating body 6
3 indicates a hole for attaching a switch with a screw or the like. Further, a pair of legs 25 having claws 24 at the ends are locking legs that are fitted into holes formed in a printed circuit board and used when a switch is embedded in the printed circuit board, for example.

<Operations and Effects of the Invention> According to the above-mentioned snap switch of this invention, the resin piece 1b is normally biased upward in FIG. A preload is applied to the tip 22 of the support plate 21.

In this state, when a downward force is applied to the resin piece 1b from above, the leaf spring 1a gradually bends from the operating portion 15 side. When this curvature reaches a certain amount, the free end of the tongue piece 12 is suddenly flipped upward due to the flatness of the leaf spring 1a. Due to this flip-up action, that is, the snap action, the movable contact 3 abuts against the fixed contact 5 at a high speed, and conduction is established between the leaf spring 1a and the fixed contact piece 8. This conductive signal is connected to the free end 14 of the support part 14.
a and the free end 8a of the fixed contact piece 8.

On the other hand, when the resin piece 1b is returned upward from the position indicated by the dotted line in FIG.
The free end of 2 suddenly moves downward, causing the fixed contact 5 to open the movable contact 3. At this time, the movable contact 3 separates from the fixed contact 5 due to the snap action caused by the flatness of the leaf spring 1a.
can increase the speed at which it leaves. This shortens the arc generation time and reduces contact deterioration.

As described above, the snap switch according to this invention has the function of a snap switch because the opening and closing operations of the movable contact 3 and the fixed contact 5 are performed by snapping the tongue piece 12 by utilizing the flatness of the leaf spring 1a. can be set.

However, the structure can be simplified because it does not require the use of a biasing spring as in the conventional case for the snap operation. Automatic assembly is possible since there is no particular need to attach a biasing spring.

Further, since there is no problem even if the resin piece 1b is rotated by a large amount, there is no need to limit the amount of movement of the mechanical part of the operating side, for example, a tape recorder. Therefore, there is no need to take into consideration the amount of movement of the mechanism, which provides the advantage of ease of design.

Furthermore, the resin piece 1b is rotated downward, and the movable contact 3
is in contact with the fixed contact 5, the resin piece 1b
When the movable contact 3 rotates further downward, the pressure contact force from the movable contact 3 toward the fixed contact 5 is applied in a direction that gradually increases. Therefore, the amount of rotation of the resin piece 1b and the contact pressure between the movable contact 3 and the fixed contact 5 have a proportional relationship, and a large contact pressure can be applied. As a result, contact resistance can be reduced.

Furthermore, when the resin piece 1b is rotated while the movable contact 3 and the fixed contact 5 are in contact with each other, the movable contact 3 and the fixed contact 5 slide relative to each other, so that the contact portion can be self-cleaned. .
As a result, a snap switch with stable contact resistance over a long period of time can be obtained.

As mentioned above, according to this invention, the structure is simple and easy to assemble, so it can be manufactured at low cost, and there is no limit to the amount of rotation of the movable part when it functions as a switch. Various effects can be obtained, such as being able to apply a large contact pressure between the two to reduce the contact resistance, and being able to maintain the contact resistance stably over a long period of time due to the self-cleaning effect. Therefore, if this idea is put into practical use, its effects will be greatly demonstrated.

In the above description, the case where the snap switch according to this invention is applied to a skeleton switch has been explained, but this invention can be applied not only to a skeleton switch but also to a micro switch. Further, by using a bimetal as the leaf spring 1a, an automatic circuit breaker can be made, and the effect is extremely great in practical use.

[Brief explanation of the drawing]

Fig. 1 is a side view for explaining a conventional snap switch, Fig. 2 is a side view showing an embodiment of this invention, Fig. 3 is a plan view showing an example of the shape of a leaf spring used in this invention; FIG. 4 is a perspective view for explaining the shape of the leaf spring used in this invention. DESCRIPTION OF SYMBOLS 1: Operation lever, 1a: Leaf spring constituting the operation lever, 1b: Resin piece, 3: Movable contact, 5: Fixed contact, 6: Insulating body, 12: Tongue piece, 13: Frame-shaped part, 14: Support part , 15: Operation section.

Claims (1)

[Scope of Claim for Utility Model Registration] A: A plate spring having a flattening property, with one end fixed and the other end serving as an operating part, and B: A tongue formed protruding from the above-mentioned operating part side of the leaf spring toward the fixed part side. A snap switch comprising: a C tongue; and a fixed contact provided opposite the free end of the tongue.