JPH0656573U - safety valve - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention improves the positioning accuracy of the compression coil spring in the fitting portion of the plate and the compression coil spring,
It also extends the life of the press die during press working,
Further, another object of the present invention is to obtain a safety valve using an inexpensive plate that facilitates surface treatment after press molding. According to the safety valve of the present invention, a body 1 of the safety valve formed in a cylindrical shape is provided with a pressure introducing port 2, and a convex ring-shaped valve seat 3 is provided on the periphery thereof, and above the valve seat 3, a central bottom surface is provided. A valve body 6 having a packing 7 fitted in the opening 4 thereof, a compression coil spring 8, and a cylindrical portion 10 formed by burring.
In a safety valve sequentially accommodating a plate 11 with a through hole 9 formed therein, a ring-shaped burr groove 14 is formed by pressing at the intersection of the lower surface 12 of the plate 11 and the outer peripheral edge of the tubular portion 10. It is characterized by.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a safety valve to be installed in a refrigeration circuit, a boiler circuit, etc. of a car air conditioner, and particularly, to improve the positioning accuracy of the compression coil spring 8 in the fitting portion of the plate 11 and the compression coil spring 8 which are components of the safety valve. The plate 11 is improved and the plate 11 can be easily manufactured.

[0002]

[Prior art]

 FIG. 2 shows a conventional safety valve. A cylinder-shaped safety valve body 1 is provided with a pressure inlet 2 at the bottom and a convex ring-shaped valve seat 3 at its periphery. On the other hand, a shoulder portion 5 for mounting a plate 11 described later is provided on the upper opening edge. Above the valve seat 3, a valve body 6 in which a packing 7 is fitted in an opening 4 at the center of the lower surface, a compression coil spring 8, and a tubular portion 10 and a passage 9 by burring are formed. The formed plates 11 are sequentially accommodated, and these parts are fixed by caulking the upper opening edge of the body 1 to the upper edge of the plate 11. Reference numeral 15 in the drawing is a male screw provided at the end portion on the pressure introducing side, which can be connected to a piping system or the like of the fluid to be controlled. 16 is an O-ring for the seal. When the pressure of the refrigerant circuit becomes higher than the set pressure, the valve body 6 overcomes the pressing force of the compression coil spring 8 and leaves the valve seat 3, and the refrigerant gas is directed from the passage 9 of the plate 11 in the axial direction of the body 1. Is released into the atmosphere, and when the pressure in the circuit drops, it is restored by the force of the compression coil spring 8.

[0003]

[Problems to be solved by the device]

 The compression coil spring 8 that defines the operating pressure of the safety valve is fixed by fitting the upper end of the compression coil spring 8 into the tubular portion 10 of the plate 11. However, since the compression coil spring 8 is functionally ground on the end face for the purpose of reducing the eccentric load, the corners are at right angles. As a result, the end surface of the compression coil spring 8 rests on the R portion, the positioning accuracy deteriorates, and the set length fluctuates, causing a problem that the valve opening pressure, which is a characteristic of the safety valve, varies. Therefore, a cutting process can be considered to eliminate the inner radius R, but the processing cost is high and it is impossible in practice. Although it is possible to make the radius R extremely small by press working, it has a bad influence on the life of the press die. Also, surface treatment such as plating is performed depending on the material of the plate 11, but since the plate upper surface 13 has no protrusions at all, the plate upper surfaces 13 are in contact with each other and cannot be adhered with the surface treatment material. As the surface treatment becomes defective, it is necessary to attach it to jigs one by one so that the plates do not easily overlap each other as a preventive measure, which is a factor of cost increase.

[0004]

[Means for Solving the Problems]

 The object of the present invention is to solve the above problems, to improve the positioning accuracy of the compression coil spring in the fitting portion of the plate and the compression coil spring, and to perform the press working. The purpose is to extend the life of the press die at that time and to obtain a safety valve using an inexpensive plate that facilitates the surface treatment after press molding.

That is, in the safety valve of the present invention, a pressure introducing port 2 is provided in a body 1 of the safety valve formed in a cylindrical shape, and a convex ring-shaped valve seat 3 is provided on the periphery thereof, and above the valve seat 3. A safety valve in which a valve body 6 in which a packing 7 is fitted in an opening 4 at the center of the lower surface, a compression coil spring 8, and a plate 11 having a cylindrical portion 10 and a through hole 9 formed by burring are sequentially housed. A ring-shaped groove 14 is provided at the intersection of the lower surface 12 of 11 and the outer peripheral edge of the tubular portion 10 by press working.

[0006]

[Action]

 Since the plate 11 used in the safety valve of the present invention is provided with a ring-shaped groove 14 at the intersection of the lower surface 12 and the outer peripheral edge of the tubular portion 10 by pressing, the tubular portion 10 is pressed. Since the inner side R due to bending is at a position deeper than the flat surface of the plate lower surface 12, the end surface of the compression coil spring 8 does not rest on the R portion at the corner of the tubular portion 10, and the valve opening pressure characteristic of the safety valve is used. It is possible to improve the accuracy of the above.

[0007]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional view of a safety valve according to an embodiment of the present invention. The safety valve of the present invention includes a body 1 having a pressure release port 2 and a valve seat 3, a valve body 6 fitted with a packing 7, a compression coil spring 8, and a cylindrical portion 10 and a through port 9 formed by burring. Although it is constituted by the formed plate 11, the role of these components is exactly the same as that of the conventional product, and therefore detailed description thereof will be omitted.

The difference of the safety valve of the present invention from the conventional product is only the plate 11 formed by press working such as burring, and this point will be described below. The plate 11 of the present invention has a semi-circular ring-shaped groove 14 formed by pressing at the intersection of the lower surface 12 and the outer peripheral edge of the tubular portion 10. That is, since the ring-shaped groove 14 is located deeper than the flat surface of the plate lower surface 12, the end surface of the compression coil spring 8 is formed by pressing the cylindrical portion 10 inside as in the conventional case. It never appears in the R section. Therefore, the position of the compression coil spring 8 can be reliably determined. Further, since the R of the ring-shaped groove 14 does not have to be particularly small, the life of the press die can be remarkably extended as compared with the conventional case. In addition, since the ring-shaped groove 14 allows the plate upper surface 13 to be raised, the plate upper surfaces 13 do not overlap each other during the surface treatment. Therefore, unlike the conventional case, it is not necessary to attach plates one by one to a jig or the like. Good.

[0009]

[Effect of device]

 According to this invention, the ring-shaped groove 14 is formed at the intersection of the lower surface 12 of the plate 11 used for the safety valve and the outer peripheral edge of the tubular portion 10 by press working. Since the inner side R by press bending is at a position deeper than the flat surface of the plate lower surface 12, the end surface of the compression coil spring 8 does not rest on the R portion of the corner of the tubular portion 10, which is a characteristic of the safety valve. The accuracy of pressure and the like can be improved. In addition, it is possible to obtain a safety valve which is excellent in both performance and price, which prolongs the life of the press die during press working and facilitates the surface treatment after press molding.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a safety valve of the present invention.

FIG. 2 is a vertical sectional view of a conventional safety valve.

[Explanation of symbols]

1 Body 2 Pressure Inlet 3 Valve Seat 4 Opening 5 Shoulder 6 Valve Body 7 Packing 8 Compression Coil Spring 9 Passage 10 Cylindrical Part 11 Plate 12
Plate lower surface 13 Plate upper surface 14 Ring-shaped groove.

Claims (1)

[Scope of utility model registration request] 1. A cylindrical safety valve body (1) is provided with a pressure introduction port (2), and a convex ring-shaped valve seat (3) is provided on the periphery of the body, and above the valve seat (3), an opening (4) at the center of the lower surface is provided. A valve body 6 in which a packing 7 is fitted, a compression coil spring 8,
Also, in a safety valve in which a cylindrical portion 10 and a plate 11 having a through hole 9 are sequentially accommodated by burring, a ring-shaped burr groove is formed at an intersection of a lower surface 12 of the plate 11 and an outer peripheral edge of the cylindrical portion 10. A safety valve characterized in that 14 is provided by press working.