JPS645328Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention includes a switch that is installed on the high pressure side of the refrigerant passage of the refrigeration cycle in an automobile cooling system, and opens a contact to stop the compressor when the pressure on the high pressure side increases or decreases abnormally; The present invention relates to a three-operation type pressure switch having a switch that can arbitrarily determine a second pressure for opening and closing a contact when the high pressure side pressure is in a normal state.

Conventionally, this type of switch has the following background. If the refrigerant in the refrigeration cycle leaks and becomes insufficient, the compressor may be destroyed. In particular, if there is a large shortage of refrigerant, the pressure on the high pressure side will drop abnormally, so a switch that operates at low pressure is required to sense this and open a contact to stop the compressor and prevent damage. If the refrigerant load in the refrigeration cycle is too large or the capacity of the condenser decreases due to some kind of defect, the pressure on the high pressure side will rise abnormally, but at that time it is necessary to stop the operation of the refrigeration cycle, and the abnormal pressure is detected and the contact is closed. I needed a switch to open it.
However, when the compressor is stopped, the pressure drops quickly, the contact is restored, and the compressor starts operating again. In this case, if there were no hysteresis in the pressures for opening and closing the pressure switch, the contacts would open and close frequently, so it was necessary to give a hysteresis to the opening and closing pressures of the high-pressure side switch. When the pressure is normal, the condensing capacity of the condenser may be controlled in order to keep the high pressure side pressure within the normal range depending on the size of the refrigeration load, etc. Therefore, a mechanism is required that closes the contact when the high-pressure side pressure exceeds a predetermined level and increases the condensing capacity, and opens the contact and reduces the condensing capacity when the pressure drops below another predetermined pressure. A pressure switch with hysteresis in the pressure at which the contacts open and close was required.

The above pressure switches are all installed in the refrigerant passage on the high pressure side of the refrigeration cycle, and the present invention aims to have the above three functions at the same time. A pressure receiving chamber is provided in the upper body above the diaphragm, and a small hole communicating with the outside is provided at the bottom of the storage chamber provided in the lower body below the diaphragm. A small diameter concave chamber is provided, and the rod at the bottom is protruded out of the small hole, and a stop ring is attached to restrict the rising position of the holder.The holder, which has an upright part with a space at the top, is loaded with a spring from below. A second electric switch is provided at the tips of first and second leaf springs fixed to the upper ends of a pair of fixed terminals, which are housed in a storage chamber so as to be biased and movable up and down, and whose lower ends protrude outside and are fixed to the lower body. a second disk is accommodated in the space of the holder, a second inversion disk is accommodated in the upper surface of the second disk that abuts the upper end of the upright portion and engages with the first leaf spring, and a hole is provided in the center of the second disk. The lower end of the second rod inserted into the lower body is hooked to the second leaf spring, and the upper end of the second rod is positioned below the second reversing disc so that it can move up and down through the insertion hole bored in the bottom of the lower body. A pair of elongated terminals inserted through the piston with their lower ends protruding outward are fixed, and an annular convex portion provided on the lower surface of the piston is brought into contact with the second reversing disk, and a second elongated terminal is attached between the two elongated terminals on the piston. A first electric switching section is provided with three leaf springs and a fixed contact, and a first desk is provided with an operating chamber for accommodating the first electrical switching section on the lower surface, and a first reversing disk attached to the upper surface of the desk is attached to a diaphragm. The lower end of the first rod that abuts the lower surface and is inserted through a hole provided in the center of the first desk is hooked to the third leaf spring, and the upper end is located below the second reversing disk. do.

An example of the present invention will be described based on the drawings.
The periphery of the diaphragm 5 and the packing 45 are sandwiched between the upper body 2 and the lower body 3 having the pressure inlet 1 and fixed together, and the pressure receiving chamber 4 communicating with the inlet 1 is inserted into the upper body 2. A small-diameter recess 7 is formed at the bottom of a storage chamber 6 provided in the lower body 3 formed of an insulating material on the upper side of the diaphragm, and a small hole 8 communicating with the outside is provided at the bottom of the recess 7. 10 is the recessed part 7
A small diameter rod 12 provided at the bottom through a step 11 projects out of the small hole 8, and is fixed at the lower end of the rod for regulating the ascending position of the holder 10. Ring 13 is attached.

A space 17 is formed on the upper surface of the holder 10 which is biased upward by a spring 15 between the locking collar 14 provided on the upper outer periphery of the holder 10 and the bottom of the recessed part 7.
A pair of raised parts 16 are provided.

Reference numeral 20 denotes first and second fixed terminals whose lower ends protrude outside the lower body, and a mounting portion 2 bent at different heights at the upper end.
The first and second leaf springs provided at the tips of the first and second leaf springs 21 and 22 whose rear ends are fixed to 0a and 20b, respectively
The contacts 23 and 24 form a second electrical switching section 25.

26 is a second desk placed on the upright part 16, and the lower end of the second rod 28 inserted into the hole 27 provided in the center passes through the opening 21a provided in the first leaf spring 21 and connects to the second leaf. Spring 22
Hang on. A second desk 26 that operates to reverse and return is installed in an annular locking portion 29 provided on the upper outer periphery of the second desk 26.
The inversion disk 30 is accommodated.

31 is a piston made of an insulating material located above the second reversing disk 30 housed in the center of the upper surface of the second desk 26 and housed in the accommodation chamber 6 so as to be able to move up and down;
A pair of elongated terminals 32 and 33, whose upper ends are bent and fixed on both sides, are inserted into insertion holes 3a provided in the lower body 31.
The lower end is inserted into the lower body 3 so as to be movable up and down, and the lower end thereof is made to protrude outside the lower body 3. The lower surface of the piston 31 is provided with an annular convex portion 31a that engages with the second reversing disk 30. or,
A third terminal whose rear end is fixed to the upper part of one long terminal 33
A movable contact 35 is attached downward to the tip of the leaf spring 34, and together with a fixed contact 32a formed on the upper part of the other fixed terminal 32, a first electrical switching section 36 is formed.

Reference numeral 37 denotes a first disk which is vertically movable on the piston 31, and the diaphragm 5 is brought into contact with a first reversing disk 39 housed in an annular locking portion 38 provided on the upper surface of the disk 37.

An operating chamber 40 for accommodating the first electrical switch section 36 is formed inside the lower surface of the first desk 37.
A hole 42 penetrating the center of the desk 37 accommodates a first rod 41 that opens and closes the first electrical switching section 36 so as to be movable up and down.

In addition, the long terminals 32 and 33 and the first and second fixed terminals 2
Although they are located 90 degrees apart from each other, they are shown on the same plane for convenience.

Next, to explain the operation of this embodiment, the pressure inside the pressure receiving chamber 4 is set to the first set pressure P1 shown in FIG.
In the following case, the holder 10 shown in FIG.
5, the second desk 26 is pushed up by the raised part 16 of the holder, and the second electric opening/closing part 2
6 is open. Further, the second reversible disk 30 is not reversed but has an upwardly convex shape, and as a result, no pressing force is applied to the second rod 28. Second inversion disk 30
The piston 31 is raised via the annular convex portion 31a, and the first reversing disk 39 mounted on the second desk 37 placed on the piston 31 is also convex without being reversed. No downward force is applied to the first rod 41 inserted into the hole 42 of the third leaf spring 37, and the third leaf spring 34, to which the lower end of the first rod 41 is engaged, does not descend, and the first electrical opening/closing portion 36 is open. Here, the force exerted by the pressure inside the pressure receiving chamber 4 on the second leaf spring 26 is determined by the effective pressure receiving area S (cm ² ) formed by the first desk 37, the lower body 3, and the diaphragm 5 and the pressure P (Kg/cm ² ) Force multiplied by F1 (Kg)
is applied downward to the second desk 26 via the first desk 37, the long terminals 32, 33, the piston 31, and the second reversing disk 30. For this, spring 1
5 force F2 (Kg) is holder 10, first desk 2
6. The piston 31 is lifted upward. As a result, PxS=F1<F2 The piston and the 1st and 2nd desks move upward PxS=F1>F2 The piston and the 1st and 2nd desks move downwards The value of pressure P that makes F1=F2 is the first set pressure Therefore, when the pressure is lower than the first set pressure, the piston and the first and second disks move upward and are lifted.

Figure 3 shows that the pressure inside the pressure receiving chamber 4 is the second set pressure P2.
The pressure inside the pressure receiving chamber 4 pushes down the first desk 37 against the elastic force of the spring 15 via the diaphragm 5, and the pushing force pushes the piston 31. The second desk 26 is also pressed down via the button. In this case, only the first contact 23 is pressed down by the second desk 26, and the first and second contacts 23,
24 are in contact with each other, and the second electrical switching section 25 is closed. In this case, both the first and second reversing disks 39 and 30 have not yet been reversed, and the first electrical switching section 36 is open.

Figure 4 shows that the pressure inside the pressure receiving chamber 4 is the second set pressure P2.
In the above state, the first inversion disk 39 is inverted downward by the pressure and becomes concave, and the first inversion disk 39 connects the third leaf spring 3 through the first rod 41.
4 to close the first electrical switching section 36. In this case, the second reversing disk 30 has not yet been reversed, and the second electrical switching section 25 remains closed.

After the second reversal disk 30 is reversed, the second set pressure P2
It is designed so that it returns upward and becomes concave at a pressure ΔP2 lower than .

Figure 5 shows that the pressure inside the pressure receiving chamber 4 is the third set pressure P3.
This shows the above state, and the second one is reversed downward.
The reversing disk 30 allows the second
The leaf spring 22 is pushed down to separate the second contact 24 from the first contact 23, opening the second electrical switching section 25. Further, as the second reversing disk 30 is reversed and moved downward, the second disk 37 and the piston 31 are also lowered. The second reversing disk 30, like the first reversing disk 39, is designed to return upward and become convex at a pressure ΔP3 lower than the third set pressure P3.

In this way, in this embodiment, the second set pressure P2 and the third set pressure P3 each have an operating hysteresis.

The present invention has the following effects.

The first and second electric opening/closing parts use the reversing load and return load of the reversing disc and the elastic force of the leaf spring, so the configuration can be simplified, and each setting pressure is independent, so pressure can be adjusted. is easy.

Since the second and third set pressures on the high pressure side utilize the reversal and return operations of the reversal disk, the electric switching section can be switched accurately.

By providing a hysteresis in the second and third set pressures when the electric switching section is opened and when it is closed, it is possible to prevent chattering at the same pressure.

By preventing chattering, it is possible to reduce the number of opening and closing operations of the electrical switching section, prevent wear on each contact, and increase the durability of the contacts.

Since this device can act as three pressure switches, it has the advantage of being small and lightweight, making it convenient to handle.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is an exploded perspective view of the whole, Figs. 2, 3, 4, and 5 are sectional views showing each operating state, and Fig. 6 shows the first and second switches. It is an explanatory view showing the relationship with each setting pressure. 2... Upper body, 3... Lower body, 4... Pressure receiving chamber,
5...Diaphragm, 6...Accommodation chamber, 10...Holder, 15...Spring, 16...Rise part,
20... fixed terminal, 23, 24, 35... contact,
25...Second electric switch section, 26...Second desk,
28, 41... Rod, 30, 39... Reversing disc, 32, 33... Long terminal, 32a... Fixed contact, 36... First electrical switching section, 37... First desk.

Claims (1)

[Scope of Claim for Utility Model Registration] The periphery of a diaphragm is sandwiched between an upper body and a lower body having a pressure introduction port, and the two are fixed together, a pressure receiving chamber is provided in the upper body above the diaphragm, and a pressure receiving chamber is provided below the diaphragm. A small diameter concave chamber with a small hole that communicates with the outside is provided at the bottom of the storage chamber provided in the lower body on the side, and the rod at the bottom is protruded outside the small hole and a stop ring is attached to set the holder in the raised position. A holder having an upright part with a space above it is biased from below by a spring and housed in a housing chamber so as to be movable up and down, and a pair of fixed terminals are fixed to the lower body with the lower ends protruding outside. A second electric opening/closing part provided at the tips of the first and second leaf springs fixed to the upper end thereof is accommodated in the space of the holder, and a second desk contacts the upper end of the upright part and engages with the first leaf spring. A second reversing disc is housed on the upper surface, the lower end of the second rod inserted through the hole provided in the second desk is hooked to the second leaf spring, and the upper end of the second rod is placed under the second reversing disc. A second annular convex portion is provided on the lower surface of the piston, to which a pair of elongated terminals are fixed, the lower ends of which are vertically movably inserted into the insertion holes drilled at the bottom of the lower body and protrude to the outside.
A first electrical switching section is provided with a fixed contact and a third leaf spring that abuts on the inversion disk and is attached between both long terminals on the piston, and an operating chamber that accommodates the first electrical switching section is provided on the lower surface. The first desk and the first inversion disk attached to the top surface of the desk are brought into contact with the bottom surface of the diaphragm, and the lower end of the first rod inserted through the hole provided in the first desk is hooked to the third leaf spring. with the top end first
Three-action pressure switch located below the reversing disc.