JPH0141143Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-action pressure switch that is attached to a high-pressure side refrigerant passage in an automobile cooling system to detect the high-pressure side pressure of a refrigeration cycle.

A conventional example of this type of pressure switch is, for example, Japanese Utility Model Application No. 58-5253. That is, a lower body 42 having a cylindrical housing 41 and a gas inlet 42
A reversing plate 48 accommodated in an operating chamber 47 provided at the lower part of a movable body 46 springed from above by a coil spring 45 is brought into contact with the upper surface of the diaphragm 44 whose peripheral edge is held between the diaphragm 44 and the diaphragm 44 . A first switch 53 consisting of a movable contact 51 and a fixed contact 52 is provided in a contact accommodation chamber 50 provided in the movable body 46, and the movable contact 51 and the reversing plate 48 are inserted through a hole 54 provided in the movable body 46. Latch it with the rod 55. In addition, the mounting portion 5 provided on the housing 41
Rods 59 and 60 attached to a holder 58 fixed to the movable body side at 7 open and close a second switch 63 consisting of a fixed contact 61 and a movable contact 62 by the movable body 46 pushed up against the coil spring 45. One rod 60 engages with the actuating piece 62b,
The other rod 59 engages with the actuating piece 62a, and the actuating piece 62a and the actuating piece 62b are interlocked by a U-shaped spring 65. The first fixed contact 52 and the first terminal 66a are connected with a lead wire 67, and the first
The movable contact 51 and the second terminal 66b are connected by a second lead wire 68.

However, the lead wires 67 and 68 that connect the first switch 53 and the terminal, which are separated from the terminal 66 fixed to the upper part of the housing 41, expand and contract following the movable body 46, which moves up and down in response to pressure changes. This makes the electric circuit complicated and difficult to actually manufacture.Furthermore, since the coil spring 45 is used, the vertical movement distance of the movable body 46 is large, resulting in a large device. In addition, the number of parts was large, the lead wires were easily damaged by metal fatigue due to expansion and contraction, and the switch lacked durability.

The present invention was developed in view of these points.In addition to providing two independent pressure switches to finely control the pressure on the high pressure side, the present invention also uses two reversing disks with different reversing pressures instead of a coil spring. The vertical movement of the piston is reduced using
Its structure is such that a pressure receiving chamber communicating with a pressure inlet is provided above a diaphragm whose peripheral edge is sandwiched between an upper body and a lower body, and a large-diameter first chamber is provided at the upper part of the lower body.
A second storage chamber with a small diameter is formed at the bottom of the storage chamber via a locking step, and a recessed portion is provided at the bottom of the second storage chamber, and a piston is inserted into the upper surface of the piston accommodated in the first storage chamber so as to be movable up and down. A second reversing disk having a snap function and protruding upward and having its upper surface abutted against the lower surface of the diaphragm is installed, and the second reversing disk has a snap function and protrudes upward with a smaller reversing pressure than the second reversing disk. on the first inverted disk attached to the bottom of the second storage chamber,
A holder having an annular protrusion on the lower surface and a concave space on the upper side is placed, the upper surface of the holder is brought into contact with the lower surface of the piston, and the lower end of the holder is made to protrude outside the lower body. The bent piece provided at the upper end of the terminal is hooked into the recessed space of the holder, and the second fixed contact attached to one side of the second terminal and the tip of the second leaf spring attached to the other side are urged upward. The second
The movable contact forms a second electric opening/closing part, and the second leaf spring and the second reversing disc are engaged with a rod passing through a hole provided in the piston, and the lower end is projected outside the lower body to connect the second leaf spring and the second reversing disc. A bent piece provided at the top of the first terminal forming a shape is arranged in a recessed part provided at the bottom of the second storage chamber, and a first fixed contact provided on one first terminal and a first fixed contact provided on the other first terminal are connected to each other.
A first electrical switching section is provided with a first movable contact provided at the tip of a first leaf spring attached to a terminal and biased upward, and a convex part provided on the first leaf spring is engaged with a first reversing disk. It is characterized by stopping.

An embodiment of the present invention will be described with reference to the drawings. The peripheral part of the diaphragm 4 and the packing 5 are airtightly sandwiched between an upper body 2 having a pressure introduction port 1 and a lower body 3 made of an insulating material. and a lower body are fixed together to form a main body 6, and a pressure receiving chamber 7 communicating with the pressure introduction port 1 is formed above the diaphragm 4 in the upper body 2.

A large-diameter first storage chamber 8 provided in the upper part of the lower body 3
A small-diameter second storage chamber 10 is formed via a locking step 9 provided continuously at the lower part of the holder, and a small-diameter recessed chamber 11 is formed below a tapered surface 12 provided at the bottom of the second storage chamber.
A recessed portion 13 is formed at approximately the same depth as the second storage chamber 10 on a straight line passing through the center of the recessed chamber.

14 is a piston housed in the first storage chamber 8 so as to be able to move up and down, and a raised part 15 is provided along the periphery of the upper surface.
A recessed chamber 16 is formed inside the recessed chamber 16, and a hole 17 is formed in the vertical direction in the center of this recessed chamber 16. Second storage room 10
A recessed space 19 is formed in the diametrical direction on the upper surface of the holder 18, which is housed in a vertically movable manner, and an annular protrusion 20 is formed along the periphery of the bottom surface of the holder.

Reference numerals 21 and 22 designate a pair of second terminals whose lower ends protrude outside the lower body 3, and the upper ends of the second terminals protrude into the second storage chamber 10, and the upper ends are bent inward, respectively. The pieces 21a and 22a have a stopper function to restrict upward movement of the holder 18 by positioning them in the recessed space 19.

A second fixed contact 23 is provided on one of the second terminals 21, and a second fixed contact is provided at the tip of the second leaf spring 24, which has an upward elastic force and has a base attached to the upper part of the other second terminal 22. A second movable contact 25 that comes into contact with and separates from 23 is provided, and both contacts 23 and 25 form a second electrical switching section 26.

The upper end of the rod 27 inserted through the hole 17 provided at the center of the piston 14 is engaged with the lower surface of the second reversing disk 28 housed in the concave chamber 16, and the rod 27
The lower end of the second plate spring 24 is engaged with the upper surface of the second plate spring 24 .

Reference numeral 30 denotes a first reversing disk having a snap function, which is engaged with the tapered surface 12 provided on the bottom surface of the second storage chamber 10, and is provided on the lower surface of the holder 18 on the upper surface of the periphery of the first reversing disk 30. The protrusion 20 is locked.

Reference numerals 31 and 32 indicate first terminals located within the recessed portion 13 and having their lower ends protruding outside the lower body 3. A first fixed contact 33 is provided on the bent piece 31a of the terminal 31, and a first fixed contact is provided on the lower surface of the tip of the first leaf spring 34, which has a base attached to the other first terminal 32 and has an upward elastic force. A first movable contact 35 that comes into contact with and separates from 33 is provided, and both contacts 33 and 35
An electrical switching section 36 is formed. A protrusion 37 that engages with the lower surface of the first reversing disk 30 is attached to the intermediate upper surface of the first leaf spring 34 .

first and second reversible discs 30 having a snap function;
28 always protrudes upward, and the first inversion disk 30 inverts downward when the pressure is higher than the first set pressure P1.
The upward return operation is performed at a pressure lower than the second set pressure P2, which is lower than the first set pressure P1. Also, the second inversion disk 28
is reversed downward when it becomes higher than the third set pressure P3, and the fourth set pressure P is smaller than the third set pressure P3.
If it is smaller than 4, it will return upward.

Next, to explain the operation of this embodiment, FIG. 2 shows a state in which the pressure P entering the pressure receiving chamber 7 from the pressure introduction port 1 is lower than the first set pressure P1, and the piston 14 is still lowered. Therefore, the second leaf spring 24 does not fall, and the second electrical switching section 26 is open.

In this case, the holder 18 is not lowered either, so the first electrical switching section 36 is open (FIG. 3).

When the pressure P in the pressure receiving chamber 7 is higher than the first set pressure P1 and lower than the fourth set pressure P4, the second reversing disk 28 does not reverse downward and the piston 14 is pushed down. The holder 18 that locks with the piston 14 is also pushed down, and the first inversion disk 30 is inverted downward by the protrusion 20 on the lower surface of the holder 18, and the protrusion 37
The first leaf spring 34 having a ? In this case, the second inversion disk 28 has not yet been inverted downward, and the second electrical switch 26 is open (FIG. 4).

When the pressure P in the pressure receiving chamber 7 becomes higher than the third set pressure P3, the piston 14 is locked to the locking step 9 and cannot drop any further, but the second reversing disk 28 is reversed downward, Second leaf spring 2 via rod 27
4 to close the second electrical switch 26 (FIG. 6). In this case, the holder 18 is the piston 14
Since the first electrical switching section 36 remains closed (FIG. 7), the first electrical switching section 36 remains closed (FIG. 7).

Note that when the pressure P becomes smaller than the fourth set pressure P4 and larger than the first set pressure P1, the second reversing disk 28 returns upward again and the second electric switching section 2
6 open (Figure 2). Further, when the pressure P becomes smaller than the second set pressure P2, the first reversing disk 30 returns upward again and opens the first electric switching section 36 (FIG. 3).

The present invention has the following effects.

By using two reversing discs with different reversing operating pressures, we create a hysteresis in the timing of contact and separation between the two electrical switching parts, which are installed separately, to prevent chattering in each electrical switching part and increase the durability of the contacts. There is.

Since a coil spring with a long stroke is not used, the entire switch can be made smaller, and the two electrical switching parts and the reversing disc are placed close together, making it easier to inspect the product and improving work efficiency.

Each electrical switching section is fixed to the lower body, and there are no moving parts in the electrical path such as lead wires, so there is little metal fatigue and durability.

Since one pressure switch has the function of two switches for two set pressures, it can be made smaller and lighter.

Since each set pressure is independent, the pressure of the first and second electrical switching parts can be adjusted even after the terminal is attached to the lower body.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; Fig. 1 is an exploded perspective view of the entire structure with the upper body omitted;
Figures 3, 4, 5, 6, and 7 are cross-sectional views showing each operating state, Figure 8 is an explanatory diagram showing the relationship between the 1st and 2nd electric switching parts and each set pressure, and Figure 9 is a conventional It is a sectional view of a seed switch. 1...Pressure introduction port, 2...Upper body, 3...Lower body, 4
...Diaphragm, 7...Pressure receiving chamber, 8...First storage chamber,
9... Locking step part, 10... Second accommodation chamber, 13... Recessed part, 14... Piston, 15... Recessed chamber, 18... Holder, 19... Recessed space part, 20... Projection part, 21, 2
2, 31, 32... terminal, 23, 33... fixed contact,
24, 34... Leaf spring, 25, 35... Movable contact, 2
6...Second electrical switching section, 27...Rod, 28...Second
Inversion disk, 30...first inversion disk, 36...first electrical switching section, 37...convex portion.

Claims (1)

[Scope of utility model registration request] A pressure receiving chamber communicating with the pressure introduction port is provided above the diaphragm whose peripheral edge is sandwiched between the upper body and the lower body, and a locking step is provided at the lower part of the large diameter first storage chamber provided at the upper part of the lower body. A second housing chamber with a small diameter is formed through the piston, and a concave portion is provided at the bottom of the second housing chamber, and the upper surface of the piston, which is housed in the first housing chamber so as to be movable up and down, has a snap function and protrudes upward. A second reversing disk whose upper surface is in contact with the lower surface of the diaphragm is attached, and the second reversing disk has a snap function that is smaller than the reversing pressure of the second reversing disk, protrudes upward, and is attached to the bottom surface of the second storage chamber. A holder having an annular protrusion on the lower surface and a recessed space above is placed on the first reversible disk, and the upper surface of the holder is brought into contact with the lower surface of the piston, and the lower end is placed outside the lower body. A bent piece provided at the upper end of the pair of second terminals that protrudes from the side is hooked into the recessed space of the holder, and the second fixed contact attached to one side of the second terminal and the second fixed contact attached to the other side are attached upward. A second movable contact provided at the tip of the biased second leaf spring forms a second electric switching part, and the second leaf spring and the second reversing disc are passed through a hole provided in the piston. A bent piece provided on the upper part of the pair of first terminals with the lower end protruding outside the lower body is placed in a recess provided at the bottom of the second storage chamber, and one of the first terminals A first electric switching part is provided by the first fixed contact provided and a first movable contact provided at the tip of the first leaf spring attached to the other first terminal and biased upward, and the first electric switching part is provided on the first leaf spring. A two-action type operating switch in which a convex portion is engaged with a first reversing disk.