JPH02260331A - Switch - Google Patents

Abstract

PURPOSE:To enlarge the stroke of a push button without any break of a movable piece by rotatably constituting the base end part side of the movable piece. CONSTITUTION:When a movable piece 42 is pushed by a push button 27, the base end part of a movable piece 24 is locked by the locking piece 35 of a terminal 33 and made rotatable, so that no stress is generated in the base end part, which has no possibility of break. Further, as the movable piece 42 is moved on the longitudinal contact side when pushed by the push button 24, a movable contact point 46 is separated while wiping a first fixed contact point 47, resulting in an improvement in depositing property to the fixed contact point 47 and also an increase in contact reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a slow type switch that switches contacts by directly transmitting pressing force from a push button to a movable piece.

(Prior art) There are two types of switches: slow type switches that transfer the external force applied to the pushbutton directly to the movable piece to switch the contacts, and switches that transfer the external force applied to the pushbutton to the movable piece through a snap action mechanism. There is also a quick type that allows you to switch instantly. Slow type and quick type each have their advantages and disadvantages, but slow type switches are used in cases where the diaphragm instantly reverses and presses the push button, such as in switches used in diaphragm pressure switches. be done.

An example of such a pressure switch is shown in FIG. A flow path 3 is formed in the axial center of a stainless steel joint 2, which has a threaded portion 1 at one end screwed into a mounting portion of a fluid device or its piping. The other end of the joint 2 is a large-diameter flange 4, and a thin seal diaphragm 5 made of stainless steel is welded to the periphery of the end surface.

The 7-flange portion 4 of the joint 2 is inserted into one tube portion of a cylindrical outer case 7 made of stainless steel and has a partition wall 6 in the middle portion, and the end edge 7a of the outer case 7 is swaged. is attached to the outer case 7.

A circular recess 8 is formed in the end 6a of the partition wall 6 of the outer case 7 on the side of the joint 2, and a pressure receiving diaphragm 9 made of stainless steel, which is thicker than the seal diaphragm 5, is installed in the recess 8.
is supported.

A hole 11 is formed in the center of the partition wall 6 of the outer case 7, which serves as a stopper for the pressure receiving diaphragm 9, through which a rod-shaped push button 10 passes. A switch case 12 made of heat-resistant resin that constitutes the outside of the built-in switch is inserted into the other cylindrical portion defined by the partition wall 6 of the outer case 7, and the other end edge 7b of the outer case 7 is inserted into the outer stepped portion of the switch case 12. The switch case 12 is attached to the outer case 7 by caulking.

The opening of the switch case 12 on the partition wall 6 side is covered with a cover 14 via a seal packing 13. A guide hole 15 is formed in the center of the cover 14, through which the push button 10 passes. A movable piece 18 is attached to the intermediate wall 16 of the switch case 12 via a terminal 1a, and a movable contact 19 is fixed to the tip of the movable piece 18. On both sides of this movable contact 19, intermediate walls 1 are provided, respectively.
Terminal 20 fixed to 6. Fixed contact 2 fixed to 21
2.23 are arranged facing each other, and each terminal 17.20
．． 21 are connected to lead wires 24°, 25.26, respectively.

In FIG. 6, the pressure of the fluid introduced into the flow path 3 of the joint 2 first deflects the seal diaphragm 5, and then when the pressure exceeds a certain value defined by the seal diaphragm 5 and the pressure receiving diaphragm 9, both are both reversed, the push button 10 is pushed, and the movable piece 18 is also pushed, and the contact of the movable contact 19 is switched from one fixed contact 22 to the other fixed contact 23, and this switching is caused by the lead wires 24 and 25. It is electrically taken out through .26.

When the pressure of the fluid introduced into the flow path 3 drops below the specified pressure, the seal diaphragm 5 and the pressure receiving diaphragm 9 are reversed again to their original states, and the movable piece 18 returns due to its own elasticity and becomes movable. The contact of the contact 19 is switched from the other fixed contact 23 to the one fixed contact 22.

(Problem to be Solved by the Invention) In such a diaphragm pressure switch, the stroke of 100 push buttons when the diaphragm is reversed is, for example, about 0.5 to 0.6 ma+, so it is difficult to switch the contact with just this stroke. cannot be done reliably. Therefore, as shown in the figure, the approximately central portion of the movable piece 19 is pressed by the push button 10 to approximately double the stroke of the movable contact 19 at the tip thereof.

By the way, when the fixed contacts 22.23 are arranged facing each other on both sides of the movable contact 19, each fixed contact 22.2
3, it is desirable that the stroke of the movable contact 19 be larger. however,
If the stroke of the movable contact 19 is large, the movable piece 18
There is a problem in that stress concentrates on the fixed portion of the movable piece 18 to the terminal 17, causing the movable piece 18 to break.

SUMMARY OF THE INVENTION An object of the present invention is to provide a switch that can extend the stroke of a push button without breaking the movable piece.

(Means for Solving the Problems) A switch according to the present invention includes a movable contact at the tip,
A movable piece whose base end is rotatably locked in the locking part of the movable terminal in the fixed contact switching direction side, whose middle part is pressed by a push button, and whose distal end is integrated with the distal end of the movable piece. became
and a movable spring whose base end is fixed to the movable terminal and curved toward the push button.

(Embodiment) FIG. 1 shows an embodiment of the present invention. A stainless steel joint 22 having a threaded portion 21 at one end screwed into a mounting portion of a fluid device or its piping has a passage 23 penetrating through its axial center. The other end of the joint 22 is a large-diameter flange 24 made of stainless steel with the same diameter as the periphery of this flange 24! The peripheral edges of four stainless steel diaphragms 26 are sandwiched between the peripheral edge of the I-made stopper 25, and these three are integrated by welding on their respective outer peripheral surfaces. 7. The opposing surfaces of the flange portion 24 and the stopper 25 are recessed to allow the diaphragm 26 to be reversed. At the center of the stopper 25 is a rod-shaped push button 27.
A hole 28 is formed for movably guiding the push button 27.
The tip end surface of the diaphragm 26 is in contact with the lower surface of the diaphragm 26.

The built-in switch in this pressure switch is the stopper 2.
The switch case 29 is made of resin and has the same diameter as the switch case 5, and the cover 30 is made of resin and has the same diameter as the case 29, closing the front opening of the switch case 29. A hole 31 for movably guiding the push button 27 is formed in the center of the cover 30. A movable side terminal 33 has a tip end protruding inside the case 29 and a rear end thereof attached to the bottom part 32 of the bottomed cylindrical case 29.
It is press-fitted into the hole 34 so as to protrude outward.

As shown in FIG. 2, this terminal 33 has a locking piece 35, which is a locking part, formed at the center of the tip, and arm parts 36 on both sides of the locking piece 35.
is formed, and the chest 37, the waist 38, and the legs 39 are formed at the bottom.
are formed sequentially. A locking protrusion 40 is formed at the tip of the locking piece 35, and step portions 41 are formed on both sides of the locking protrusion 40. A locking hole 43 formed at the proximal end of the movable piece 42 is inserted into the locking protrusion 40, and the periphery thereof is supported by the stepped portion 41, so that the movable piece 42 is connected to the locking piece 35 as shown in the figure. The movable piece 42 is locked so as to be rotatable in the vertical direction, that is, in the fixed contact switching direction, and movable in the longitudinal direction of the movable piece 42 . The locking hole 43 may be a U-shaped cut that is open on the proximal end side. Also, on the chest 37 of the terminal 33, there are two bosses 4.
4 are formed protruding toward the other side, and the bifurcated base end portions of a conductive movable spring 45, which is U-shaped and curved upwardly as a whole, are fixed to these bosses 44 by crimping. . The distal ends of the movable piece 42 and the movable spring 45 are overlapped with each other and are integrated with each other by a movable contact 46. Reference numeral 42a indicates a protrusion with which the lower end surface of the push button 27 comes into contact. In addition, the movable piece 42 and the movable spring 45 may be integrally formed from the beginning with - sheets of conductive leaf spring material.

When the terminal 33 assembled in this way is press-fitted from the inside of the case 29 into the hole 34 formed in the bottom part 32 of the case 29 from the leg part 39 in FIG. The side portion of the hole 34 is engaged with the peripheral edge of the hole 34 to determine the position in the press-fitting direction. After being positioned in this manner, both sides of the leg portions 39 of the terminal 33 are bent inward so that the entire leg portion 39 forms a U-shape as shown in FIG. As a result, the terminal 33 is prevented from being pulled out in both directions by the arm part 36 on the inside of the case bottom part 32 and by the bent leg part 39 on the outside, and is securely fixed to the bottom part 32.

When the terminal 33 is fixed to the switch bottom 32 in this manner, the movable contact 46 at the tip of the movable piece 42 assumes a position in which it contacts the first fixed contact 47 on the push button 27 side. A second fixed contact 4 is placed at a predetermined distance from this first fixed contact 47.
8 is facing.

The first fixed contact 47 is crimped to the tip of the horizontal tip 50 of the first fixed terminal 49 . First fixed terminal 49
The intermediate portion of the switch is bent at a substantially right angle toward the switch bottom 32, and is press-fitted into the hole 51 of the bottom 32, as shown in FIG. The rear end portion of the first fixed terminal 49 also has a single-shaped leg portion similar to the terminal 33, and has a leg portion 52 protruding from the hole 51 to the outside of the bottom portion 32, as shown in FIG. Then, fold both sides inward into a U-shape and fasten the ends.

Similarly, the second fixed contact 48 is crimped to the tip of the horizontal tip 54 of the second fixed terminal 53, and the middle part of the second fixed terminal 53 is bent at a substantially right angle toward the bottom 32. It is press-fitted into the hole 55 of the bottom part 32, and the one-shaped leg part 56 protruding from the bottom part 32 is bent inward into a U-shape to stop handling.

The part of the bottom 32 from which the legs 39,52,56 of each terminal protrude is formed with a frustoconical seat 57,58,59, into which each leg 39,52,56 faces outward. A bag-shaped hole 60.61°62 is formed from the hole. Then, from the legs 39, 52.56 of these terminals, the holes 60.6
1.62, each lead wire 63. as shown in FIG.
Insert and hold the 64°65 core wires, and each core wire has three legs.

Solder to 52.56.

A cover 30 is placed over the front opening of the case 29 where the terminals 33, 49.5.15 and lead wires 63, 64.65 are assembled in this way, and the push button 27 is then inserted into the hole 31 of the cover 30. After that, the cover 30 of these switch assemblies is attached to the stopper 2 of the diaphragm assembly.
5, and both assemblies are joined together by an outer case 66 made of stainless steel.

The outer case 66 has a stepped cylindrical shape, and its intermediate step is placed against the bottom 32 of the switch case 29, and the peripheral edge of one end is crimped to the flange 24 of the joint 22, so that both assemblies are integrated. be converted into An outer case 6 extends to cover the lead wire connection portion of the switch assembly.
A sealing material 67 such as epoxy resin is filled into the outer case 66 from the other end of the outer case 66 to prevent dust, water, and rust within the outer case 66.

Next, the operation of this pressure switch will be explained.

When the pressure of the fluid introduced into the flow path 23 of the joint 22 becomes higher than a specified value, the diaphragm 26 reverses and pushes the push button 27. As a result, the push button 27 pushes the movable piece 42, so the movable contact 46 switches from contact with the first fixed contact 47 to contact with the second fixed contact 48, which causes the movable spring 45 to move the terminal 33 and the first, Second fixed terminal 49
, 537'l' are output as electrical signals to the outside through lead wires 63, 64, and 65.

When the movable piece 42 is pressed by the push button 27, the base end of the movable piece 42 is locked to the locking piece 35 of the terminal 33 and can rotate, so that no stress is generated at the base end. There is no risk of breakage. Further, when the movable piece 42 is pushed by the push button 27, the movable piece 42 moves toward the contact in the longitudinal direction, so the movable contact 46 separates while wiping the first fixed contact 47, and the weldability to the fixed contact 47 is reduced. As the contact quality improves, the contact reliability also increases.

When the pressure of the fluid introduced into the flow path 34 falls below the specified value, the diaphragm 26 is reversed again to its original state, and the movable contact 46 is moved to the second fixed contact 4 by the return force of the movable spring 45.
8 is switched to contact with the first fixed contact 47, and the movable piece 35 pushes the push button 27 back to its original state.

Although the above embodiment is an example in which the present invention is applied to a built-in pressure switch, the present invention can be applied to various slow type switches. Further, the locking between the base end of the movable piece and the locking portion of the movable terminal may be of any configuration as long as it is rotatable in the fixed contact switching direction.

(Effects of the Invention) As described above, the switch according to the present invention includes a movable contact at the distal end, and the base end is locked to the locking portion of the movable terminal so as to be rotatable in the fixed contact switching direction. A movable piece whose intermediate part is pressed by a push button, and a movable spring whose distal end is integrated with the distal end of the movable piece, whose base end is fixed to the movable terminal and is curved toward the push button. Therefore, even if the stroke of the push button is greatly expanded on the movable contact side, the base end side of the movable piece can rotate, so the movable piece will not break and the contact pressure against the fixed contact will be reduced. If enough is taken, contact reliability will increase. Furthermore, by variously changing the locking position of the base end of the movable piece with the terminal, various lever ratios, that is, stroke magnifications can be obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a pressure switch showing an embodiment of the present invention, FIG. 2 is a perspective view of a movable terminal assembly in the same pressure switch, and FIG. 3 is a sectional view of a built-in switch in the same pressure switch. Figure 4 is a right side view of Figure 3 and Figure 5 is a right side view of Figure 3.
The figure is a left side view of FIG. 3 with the cover removed, and FIG. 6 is a sectional view showing an example of a conventional pressure switch. 22...Joint, 23...Flow path, 25...Stopper, 26...Diaphragm, 27...Push button, 29
...Switch case, 30...Cover, 33...
Movable side terminal, 35...locking piece (locking part>, 39, 52
．． 56... Leg portion, 42... Movable piece, 45... Movable spring, 46... Movable contact, 47.48... Fixed contact, 49.53... Fixed terminal, 60.61. 62...
Bag-shaped hole, 63.64°65...Lead wire, 66...
・Outer case, 67...Sealing material.

Claims (1)

[Claims] The distal end has a movable contact, the proximal end is rotatably locked in the locking part of the movable terminal in the fixed contact switching direction, the intermediate part is pressed by a push button, and the distal end is a movable piece. A switch comprising: a movable spring integrated with a distal end portion of the movable piece, a proximal end portion fixed to the movable side terminal, and curved toward the push button side.