JPH0125470Y2 - - Google Patents

Description

[Detailed description of the invention] "Industrial application field" This invention is installed on the high-pressure side of the refrigeration cycle of an automobile cooling system, and when the pressure on the high-pressure side of the refrigeration cycle circuit abnormally increases or decreases, the compressor This relates to a two-action pressure switch that has the function of turning off a series of electrical contacts.

``Prior art'' Conventionally, this type of pressure switch, for example,
To explain No. 127543 with reference to FIGS. 9 and 10, a lower body 54 is fitted into an upper body 51 having a pressure introduction port 55 above through a locking plate 53 having a large diameter opening 52 in the center. The lower end of the upper body 51 is caulked, and the peripheral edge of the diaphragm 56 is airtightly clamped together with the seal packing between the upper body and the locking plate, thereby providing a pressure receiving chamber 57 above the diaphragm.

The outer periphery of the disc spring 60 is hooked to a locking step 59 provided at the lower part of the working chamber 58 formed inside the upper part of the lower body 54, and the switch 61 is installed in a small diameter accommodation chamber provided below the working chamber 58. .

A hooking portion 64 is provided on the lower inner surface of a piston 62 which is housed in the working chamber 58 so as to be able to move up and down in contact with the lower surface of the diaphragm 56 . Further, an annular convex portion 69 is provided on the holder 66, which has a cylindrical portion 67 in the center of which a rod 68 is mounted so as to be movable up and down.

The peripheral edge of the reversing disk 2 protruding downward is latched to a latching portion 64 inside the piston, and the reversing disk comes into contact with an annular convex portion 69 of the holder and is housed in the piston and the holder in a free state. , and is housed in a working chamber 58 of the lower body so as to be vertically movable.

Therefore, when the pressure inside the pressure receiving chamber 57 is not applied to the inversion disk 2, or when the applied pressure P is smaller than the pressure P2 shown in FIG. 8 (however, P>P1),
The inversion disk 2 is in the state shown in FIG. 9 with almost no deformation. Therefore, the overstroke A (Fig. 10) in which the piston 62 and the holder 66 move downward to turn on the switch 61 and further push down the rod 68 at the pressure P1 shown in Fig. 8 (Fig. 10) is reversed as shown in Fig. 7. It must be the same as the free height b of the disc 2. That is, unless the stroke b to the jumping center S when the reversing disk 2 is reversed from the free state N is equal to the overstroke A, the pressure will increase to P2 and the reversing disk 2 will reverse upward. The jump center S and the timing at which the switch 61 was turned off were not the same.

Here, after the piston 62 is pushed down by pressure and latched to the locking step 59, the pressure causes the leaf spring of the switch to be bent downward by the rod via the piston and the reversing disk. Represents distance, ie overstroke. b represents the stroke from the free state N to the jump center S when the inversion disk is inverted, that is, the free height of the inversion disk. C represents the stroke from when the piston receives almost no pressure until it is pushed down and locked into the locking step.

"Problem to be solved by the invention" In this way, in the conventional pressure switch, the overstroke A and the stroke b from the free state N to the jumping center S when reversing are equal (A
=b) As a result, stroke C at low pressure of P1
must be at least greater than overstroke A.

Also, when the pressure is lower than P1, switch 61
It is necessary to have a sufficient contact gap for practical purposes.
It must be made larger by about 0.3mm. That is, in a practical product, the stroke b is about 0.6 mm, so the stroke C had to be 0.3+0.6=0.9 mm. This size has been a big problem in practice because it is difficult to increase the stroke of the diaphragm with a small pressure switch.

"Means for Solving Problems" In view of the above problems, the present invention incorporates an inversion disk in a compressed state rather than in a free state into a piston and a holder, and its configuration includes a pressure introduction port. The periphery of the diaphragm is airtightly fixed between the upper body and the lower body to form a pressure receiving chamber in the upper body, and the pressure switch has an electric switch in the lower body. A piston is provided with a latching part on the inside of the lower part and has a plurality of claw pieces protruding from the outer periphery, an actuating convex part for reversing the reversing disk upwards, a guide cylinder part is provided in the center, and a plurality of claws are provided on the inside of the upper part. and a holder having a locking pawl, and the peripheral edge of the reversing disk that comes into contact with the operating convex part of the holder and protrudes downward is hooked to the latch part of the piston and compressed. The holder is assembled into a piston and a holder, and the claws of the piston are engaged with the locking claws of the holder.The holder is housed in the working chamber of the lower body so as to be movable up and down, and the center of the holder is made to protrude upward, and the guide cylinder part is inserted into the holder. The outer periphery of a disc spring, which has a through hole for insertion, is hooked to a locking step provided at the lower part of the working chamber, and the upper end of the rod, which is vertically movably inserted through the guide tube, is attached to the reversing disc, and the lower end is characterized in that it is brought into contact with an electric switch.

"Operation" Since the reversing disk is assembled into the piston and holder in a compressed state rather than in a free state, the distance from the assembled state of the reversing disk to the jump center is shortened, and the reversing disk is The stroke before reversing can be made smaller.

"Example" An example of the present invention will be described based on the drawings.
The peripheral edge of the diaphragm 14 is held between an annular seal packing 13 housed in an upper body 12 having a pressure introduction port 11 and a locking plate 15, and a lower portion is placed below the locking plate 15 in the upper body 12. The lower end of the upper body 12 is caulked to accommodate the body 16.

A fixed contact 23 is attached to the upper part of one terminal piece 21 of a pair of terminal pieces 21 and 22 whose lower ends protrude to the outside in the lower part of the lower body 16, and a fixed contact 23 is attached to the top of the other terminal piece 22. Attach the rear end of the leaf spring 25 having the movable contact 24, and connect the fixed contact 23 and the movable contact 2.
An electric switch 26 formed by 4 is attached.

An annular locking step 28 is formed at the lower part of the working chamber 18 provided inside the upper part of the lower body 16, and a holder 29 is housed in the working chamber 18 so as to be movable up and down.
A piston 35 is housed within the holder 29.

The large diameter opening 15 of the locking plate is located at the center of the piston 35.
A circular head 39 located inside the head is provided, and an annular hook that hooks the peripheral edge of the inversion disk 2 is provided on the lower inner surface of the slope portion 35a that hooks with the locking plate 15 provided below the head. A stop portion 36 is provided, and a plurality of claw pieces 37 are provided protruding outward from the bottom of the piston.

Reference numeral 29 denotes a holder, which has a guide cylinder part 30 with its central part protruding downward, a rising wall 31 formed by raising the outer peripheral edge of the holder upward, and a holder which is separate from the rising wall 31 and further outside. The upper ends of the plurality of standing parts 32 placed upright are bent inward to attach the locking claws 33.
A piston 35 is formed and housed in the upright wall 31.
is rotated in either direction to lock the claw piece 37 to the lower side of the locking claw 33, and the reversing disk 2 is assembled into the piston and holder in a compressed state.

An annular operating convex portion 34 is provided by protruding upward from the center of the holder 29 by approximately 1/2 radius, and serves as a fulcrum when the reversing disk 2 is reversed. Also, a disc spring 3 is attached to the inner end of the locking step portion 28.
8, and insert the guide cylinder portion 30 of the holder into the through hole 38a provided in the center of the disc spring. The lower end of the rod 40, which is inserted into the guide tube 30 so as to be able to move up and down, is in contact with the upper surface of the leaf spring 25, and the upper end is in contact with the lower surface of the reversing disk 2.

In the figure, 42 is a pressure receiving chamber formed in the upper body 12 and communicating with the pressure introduction port 11 above the diaphragm 14.

Next, to explain the operation of this embodiment, when the pressure inside the pressure receiving chamber 42 increases, it is transmitted to the piston 35 via the diaphragm 14, and the pressing force of the piston 35 is applied to the peripheral edge of the latch 36 in the piston 2. The force is transmitted to the stopped reversing disk 2, and pushes down the disc spring 38 via the holder 29 housing the piston 35 (FIG. 1).

When the pressure inside the pressure receiving chamber 42 reaches a low pressure P1 determined by the piston 35 and the disc spring 38, the disc spring 38 bends downward, and the guide cylinder part 30 of the holder
The leaf spring 2 that the lower end of the rod 40 attached to comes into contact with
5 downward to turn on the electric switch 26 (Fig. 2). In this case, the inversion disk 2 is not yet inverted upwards.

Next, when the pressure inside the pressure receiving chamber 42 increases to P2 or higher, a downward constriction load is applied to the peripheral edge of the reversing disk 2 that is latched to the latching portion 36 of the piston 35, and as a result, the reversing The central portion of the disk 2 is flipped upwards using the operating convex portion 34 of the holder 29 as a fulcrum (FIG. 3). Due to the upward reversing operation of the reversing disk 2, the pressing force on the rod 40 is released, and due to the elastic force of the leaf spring 25, the rod 40 rapidly rises until the upper end of the rod 40 comes into contact with the reversing disk 2, and electricity is generated. Switch 2
Turn 6 off.

The claw piece 37 provided on the piston 35 is attached to the holder 2.
The reversing disk 2, which protrudes downward, is installed between the piston and the holder in a downwardly compressed state rather than in a free state. Therefore, the stroke d from the jump center S when the reversible disk having the same free height b as the conventional one is reversed from the assembled state M (Fig. 8)
is the jump center S when reversing from the free state N
The stroke b can be made smaller than the previous stroke b (b>d).

Therefore, the overstroke a of the electric switch 26
(Fig. 2) should be the same as d, so the stroke c (Fig. 1) when the pressure is low should be larger than d. For example, if the design is made so that d=0.3mm, the stroke c will be c=0.3+0.3=0.6
mm, making it sufficiently compact for practical use compared to conventional switches.

"Effect of ideas" The present invention has the following effects.

The rod that opens and closes the electric switch has a complex configuration and requires an expensive electric switch to perform two operations, as it moves not only downward in one direction but also upwards from the middle. I don't.

Because the electric switch has a simple and thin structure, the entire switch can be made smaller and lighter, making it ideal for on-vehicle use.It also facilitates assembly work, further improves work efficiency, and reduces costs.

Since the stroke of the diaphragm can be shortened, durability can be increased.

Since the operating points of the electric switches each have a hysteresis, there is no chattering and it is quiet.

It's quiet because there's nothing to let out.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is an overall cross-sectional view, FIGS. 2 and 3 are cross-sectional views showing operating states, and FIG. 4 is a perspective view of a piston with some parts cut out.
Figure 5 is a perspective view of the reversing disc with some parts missing, Figure 6 is a perspective view of the holder with some parts missing, Figure 7 is a sectional view of the reversing disc, and Figure 8 shows how the load and the reversing disc are reversed. Explanatory diagram showing the relationship with the stroke during operation, Nos. 9 and 10
The figures are cross-sectional views showing the operating states of a conventional pressure switch. 2... Inversion disk, 11... Pressure introduction port, 12...
...Upper body, 14...Diaphragm, 16...Lower body, 18...Working chamber, 26...Electric switch, 8...
...Latching stepped portion, 29...Holder, 30...Guide cylinder portion, 33...Latching claw, 34...Operation convex portion, 35
... Piston, 36 ... Latching part, 37 ... Claw piece,
38...disc spring, 38a...through hole, 40...rod, 42...pressure receiving chamber.

Claims (1)

[Scope of utility model registration request] In a pressure switch, the peripheral edge of a diaphragm is airtightly fixed between an upper body having a pressure inlet and a lower body to form a pressure receiving chamber in the upper body, and an electric switch is provided in the lower body. A piston is provided with a latching part on the inside of the lower part, and has a plurality of claw pieces protruding from the outer periphery, an actuating convex part for reversing the reversing disk upwards, a guide cylinder part is provided in the center, and the upper part It consists of a holder with a plurality of locking claws on the inside, and the circumferential edge of the inversion disk that comes into contact with the operating convex part of the holder and projects downward is hooked to the locking part of the piston and compressed. The inverting disk is assembled into the piston and the holder, and the holder, in which the claws of the piston are engaged with the locking claws of the holder, is housed in the working chamber of the lower body so as to be movable up and down, with the center protruding upward. The outer periphery of a disc spring, which has a through hole through which the guide tube is inserted, is hooked to a locking step provided at the bottom of the working chamber, and the upper end of the rod, which is inserted through the guide tube so that it can move up and down, is connected to the inversion circle. A two-action pressure switch with the bottom end touching the plate and the bottom end touching the electric switch.