CN111936778A

CN111936778A - Overflow valve

Info

Publication number: CN111936778A
Application number: CN201980021520.1A
Authority: CN
Inventors: 柳田保昌; 药师神忠幸; 平松浩司; 森田智也
Original assignee: Fujikin Inc
Current assignee: Fujikin Inc
Priority date: 2018-03-26
Filing date: 2019-03-25
Publication date: 2020-11-13
Also published as: WO2019188883A1; KR20200121865A; TW201940797A; JPWO2019188883A1

Abstract

The invention provides a relief valve, which is simple in adjustment of set pressure and can monitor the change of the set pressure after setting. The overflow valve includes: a valve body (2) provided with a fluid inflow passage (2 a); an annular valve seat (3) provided to the valve body (2); and a valve element (4) that is housed in the valve body (2) and is biased toward the valve seat by a biasing member (7), wherein in the relief valve (1), the valve element (4) is moved by the fluid pressure in the fluid inflow passage (2a) to open and close the fluid inflow passage (2a), the biasing force of the biasing member (7) is adjustable, and the relief valve (1) is provided with a sensor (22) that detects the biasing force on at least one end side of the biasing member (7).

Description

Overflow valve

Technical Field

The present invention relates to a relief valve for setting a pressure of a fluid to a predetermined value or less.

Background

In some devices using a fluid, it is required to reduce the fluid pressure to a predetermined value or less when the fluid pressure becomes a predetermined value or more for safety or the like.

As a relief valve, there is known a structure including: a valve body provided with a recess and a fluid inflow passage communicating with the recess; an annular valve seat provided on the valve body; and a valve element that is housed in the valve body and is biased against the valve seat by a biasing member, and the valve element moves by a fluid pressure in the fluid inflow passage to open and close the fluid inflow passage (patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese Kokai publication Sho 63-154874

Disclosure of Invention

Problems to be solved by the invention

According to the relief valve described above, when the fluid pressure exceeds a predetermined value (the biasing force of the biasing member), the valve body moves to open the fluid inflow passage, so that the fluid pressure automatically returns to the predetermined value or less, thereby ensuring the safety of the device provided with the relief valve.

The urging member is, for example, a compression coil spring. When a compression coil spring is used as the urging member, the set pressure of the relief valve can be adjusted by changing the degree of compression of the compression coil spring. In order to set the degree of compression of the compression coil spring, a fluid such as a gas having a plurality of pressures is actually caused to flow into the relief valve, and the following operation is repeated to adjust the relief valve to operate at the set pressure: if the relief valve is operated before the set pressure is reached, the compressibility of the compression coil spring is improved, and if the relief valve is not operated at the set pressure, the compressibility of the compression coil spring is reduced. This operation is very troublesome, and the fluid such as gas is wasted because it is discarded after one use.

Further, the biasing member such as a compression coil spring has a reduced elastic constant due to so-called spring fatigue caused by long-term use, and a reduction in biasing force occurs. Further, the biasing force changes due to a change in the elastic constant in a low-temperature environment or a high-temperature environment, a loosening of a screw mechanism or the like that biases the compression coil spring, or the like.

The invention aims to provide a relief valve which is simple in adjustment of set pressure and can monitor change of set pressure after setting.

Means for solving the problems

The relief valve of the present invention includes: a valve body provided with a fluid inflow passage; an annular valve seat provided on the valve body; and a valve element that is housed in the valve body and is urged toward the valve seat by an urging member, the valve element being movable by a fluid pressure in the fluid inflow passage to open and close the fluid inflow passage, the relief valve being characterized in that the urging force of the urging member is adjustable, and a sensor that detects the urging force is provided on at least one end side of the urging member.

According to the relief valve of the present invention, since the sensor for detecting the biasing force is provided on at least one end side of the biasing member, the set pressure of the relief valve can be directly set based on information from the sensor. If the sensor is a pressure sensor, the pressure can be set to the set pressure directly from the information of the pressure sensor, and if the sensor is a load sensor, the pressure at that time can be obtained by dividing the detected load by the pressure receiving area of the load sensor. Further, a strain gauge or the like can also be used as the sensor.

Preferably, the valve body is biased via a support member that supports the biasing member, and the sensor is interposed between the valve body and the support member.

The urging member is a compression coil spring, and a receiving member for supporting the compression coil spring is provided, and a sensor is provided between the compression coil spring and the valve body, whereby information from the sensor can be stably acquired.

Preferably, the relief valve has a transmission unit that transmits information detected by the sensor. The transmitter may be built in the sensor itself or may be provided independently of the sensor.

The relief valve is preferably combined with a monitoring device provided with a personal computer or the like to form a valve monitoring system, and in this case, the monitoring device includes: a communication unit that receives signals from the sensors; a determination unit that determines whether or not the sensor is acceptable based on the signals received from the sensors; and a storage unit that stores the result determined by the determination unit.

Effects of the invention

According to the relief valve of the present invention, the setting of the set pressure is facilitated by providing the sensor for detecting the biasing force of the biasing member, and the change in the set pressure with time can be confirmed, so that the resetting of the set pressure and the like can be facilitated.

Drawings

Fig. 1 is a longitudinal sectional view showing one embodiment of a relief valve of the present invention.

Fig. 2 is a diagram showing a monitoring system of a valve using the relief valve of the present invention.

Detailed Description

Embodiments of the present invention are explained with reference to the following drawings. In the following description, the upper, lower, left, and right refer to the upper, lower, left, and right of fig. 1.

Fig. 1 shows an entire embodiment of a relief valve according to the present invention.

As shown in fig. 1, the relief valve 1 is configured to maintain the pressure of the fluid flowing into the passage 2a at or below a predetermined value by discharging a part of the fluid when the pressure of the fluid flowing into the passage 2a 0 exceeds the predetermined value, and includes: a valve body 2 having a fluid inflow passage 2a, a fluid outflow passage 2b, and a recess 2 c; an annular valve seat 3 provided at the periphery of the upward opening of the fluid inflow passage 2 a; a rod-shaped valve element 4 that is pressed against the valve seat 3 (moved in the closing direction) or separated from the valve seat 3 (moved in the opening direction) to open and close the fluid inflow passage 2 a; a cylindrical bonnet 5, the lower part of which is inserted into the upper part of the recess 2c of the valve body 2 and extends upward; a cylindrical cap 6 having a lower end fixed to an upper end of the bonnet 5; a compression coil spring (urging member) 7 that urges the valve element 4 downward; an O-ring 8 embedded in the valve seat 3; a cylindrical O-ring pressing portion 9 that is fixed to the valve body 2 and presses the O-ring 8 from above; and a sensor 22 for detecting the urging force (e.g., pressure) generated by the helical spring 7.

The fluid inflow passage 2a opens downward and extends upward and downward, and has an upper end opening at the bottom surface of the recess 2c of the valve body 2. The fluid outflow passage 2b opens to the right of the valve body 2, extends to the left and has its left end opening to the right side surface of the recess 2 c.

The valve seat 3 is formed as a separate member from the valve body 2, is detachably fitted into the recess 2c of the valve body 2, and is supported by the bottom surface of the recess 2 c. The inner diameter of the valve seat 3 is formed slightly smaller than the diameter of the fluid inflow passage 2 a.

The valve seat 3 includes: an abutment portion 11 whose lower surface abuts against the bottom surface of the recess 2c of the valve body 2; and a support portion 12 integrally provided above the contact portion 11 and supporting the O-ring 8. The valve seat 3 may be a separate member from the valve body 2, or the bottom surface of the recess 2c may be formed directly as the valve seat 3.

The valve body 4 includes a large diameter portion 13 and a small diameter portion 14, and the small diameter portion 14 is located above the large diameter portion 13 and has an outer diameter smaller than the large diameter portion 13. The outer diameter of the large diameter portion 13 is formed slightly larger than the inner diameter of the valve seat 3.

The bonnet 5 is fixed to the upper portion of the valve body 2 by screwing an external thread portion provided at the lower portion thereof with an internal thread portion provided at the upper portion of the recess 2c of the valve body 2. A small-diameter inner peripheral portion 16 that slidably guides the small-diameter portion 14 of the valve body 4, and a large-diameter inner peripheral portion 17 that slidably guides the upper portion of the large-diameter portion 13 of the valve body 4 are provided on the inner periphery of the bonnet 5.

An annular recess 17a is provided at a lower end portion of the large-diameter inner peripheral portion 17 of the bonnet 5, and an X-ring 19 supported by the holder 18 is disposed in the recess 17 a. Instead of the X-ring 19, a member capable of supporting the large-diameter inner peripheral portion 17 may be an O-ring or the like.

The cap 6 is fixed to the upper end portion of the bonnet 5 by screwing the lower end portion of the female screw portion provided on the inner periphery thereof with the upper end portion of the male screw portion provided on the upper portion of the bonnet 5. A lock nut 20 for preventing loosening of screwing of the cap 6 and the bonnet 5 is screwed to the middle of the external thread portion of the bonnet 5.

The compression coil spring 7 is sandwiched between the lower surface of the top wall 6a of the cap 6 and the upper surface of a spring seat (receiving member) 15 disposed in the bonnet 5. The lower surface of the spring seat 15 is supported by the upper end of the small diameter portion 14 of the valve body 4.

The sensor 22 in fig. 1 is interposed between the receiving member 15 of the compression coil spring 7 and the small diameter portion 14 of the upper portion of the valve body 4. With such a configuration, the downward urging force generated by the compression coil spring 7 can be accurately detected.

The cover 6 and the valve body 2 are connected by the wire 10, whereby the cover 6 is fixed not only to the bonnet 5 but also to the valve body 2.

The O-ring pressing portion 9 is fixed to the lower portion of the valve body 2 by screwing a male screw portion provided at the upper portion thereof with a female screw portion provided at the lower portion of the recess 2c of the valve body 2.

A female screw is formed in the center of the top wall 6a of the cap 6 to screw a bolt 21 having a male screw portion to be screwed with the female screw.

A recess is provided in the lower surface of the spring seat 15, the sensor 22 can be provided in the recess by bonding or press-fitting, and the lower surface of the sensor 22 is formed to abut against the upper end surface of the small diameter portion 14 above the valve element 4.

According to this relief valve 1, when the pressure of the fluid in the fluid inflow passage 2a rises and exceeds the elastic force (biasing force) of the compression coil spring 7 that biases the valve element 4, the valve element 4 moves upward, whereby the fluid inflow passage 2a is opened, and a part (or all) of the fluid flows through the recess 2c of the valve element 2 and is discharged to the outside from the fluid outflow passage 2 b. Thereby, the pressure of the fluid in the fluid inflow passage 2a is reduced, the elastic force of the compression coil spring 7 exceeds the pressure of the fluid, and the fluid inflow passage 2a is restored to the closed state. The amount of screwing of the cap 6 and the bonnet 5 can be adjusted, and the elastic force of the compression coil spring 7 can be increased by tightening the cap 6 more against the bonnet 5. Therefore, the set value of the pressure of the fluid in which the fluid inflow passage 2a is opened can be arbitrarily set by adjusting the elastic force of the compression coil spring 7.

When the sensor 22 is a pressure sensor and a signal relating to the pressure detected by the sensor 22 is taken out to the outside by wire or wirelessly to grasp the detected pressure, the pressure at which the relief valve 1 is actually operated can be grasped. If the detected pressure is lower than the set pressure, the amount of screwing the cap 6 and the bonnet 5 is increased to tighten the cap more, and the adjustment is performed. Further, if the detected pressure is higher than the set pressure, the amount of screwing between the cap 6 and the bonnet 5 may be reduced and the tightening may be reduced.

Fig. 2 is a schematic diagram showing an example of a monitoring system including a monitoring device 40 and the relief valve 1 incorporating the sensor 22.

The figure shows 1 relief valve 1 installed in a plant or a factory.

The sensor 22 provided in the relief valve 1 transmits the identification number of the relief valve 1 to the monitoring device 40 by wireless, and the identification number is received by the receiving antenna 41 of the receiving unit 42 and temporarily stored in the determination unit 43.

Next, the signal from the position sensor 22 enters the receiving unit 42 of the monitoring device 40 via a signal line (no reference numeral) and is transmitted to the determination unit 43. In addition to signal transmission via a wired signal line, a wireless signal transmission method may be used.

The determination unit 43 determines whether or not the signal from the relief valve 1 is within the allowable range of the set pressure, and stores the determination result and the identification number in the storage unit 44. The corresponding information can be displayed and confirmed on a display unit (not shown) of the monitoring device 40. The determination unit 43 may be built in the relief valve 1, or the determination result may be directly transmitted from the relief valve 1 to a mobile phone or a personal computer of a person in charge.

The monitoring system transmits information corresponding thereto to the transmission unit 45, and can transmit the information to the central management server 48 by transmitting radio waves from the transmission antenna 46 to the internet 47. The connection to the internet is not limited to wireless, and wired direct connection may be used.

When the signal from the relief valve 1 exceeds the allowable range of the set pressure, the content of exceeding the allowable range of the set pressure of the relief valve 1 is transmitted to, for example, a cellular phone or a personal computer of the person in charge by mail, whereby the person in charge can grasp in real time the abnormality of the device provided with the relief valve 1 and can take necessary measures.

The relief valve 1 is not limited to the structure shown in fig. 1, and may be any relief valve as long as the fluid inflow passage can be opened by moving the valve element by the fluid pressure, and the above-described sensor 22 is provided, whereby the operating pressure information of the relief valve can be grasped, and the relief valve can appropriately cope with an abnormality.

In the embodiment, the compression coil spring 7 is used as the urging member that urges the valve body 4, but the urging member is not limited to a spring. For example, various methods such as a method of using an elastic body such as rubber or a flexible member, a method of applying force by the pressure of fluid such as a hydraulic piston or an air pressure piston, and a method of using electric power by combining an electric motor with dimensions or the like can be employed. The position where the sensor 22 is provided is not limited to the position between the valve body 4 and the spring seat 15, and may be provided on the top wall 6a (or the plug 21) of the cap 6. In this case, a member corresponding to the spring seat 15 may be provided at the upper end portion of the compression coil spring 7. Further, the sensor 22 is interposed between the top wall 6a (or the plug 21) of the lid 6 and the spring seat 15, and the pressure can be measured.

As the method of adjusting the biasing force when using the above-described various biasing methods, for example, in the case of using an elastic body, the biasing force can be appropriately adjusted based on the same screwing amount as in the embodiment, in the case of using the fluid pressure, the biasing force can be appropriately adjusted by the pressure regulator, and in the case of using the electric power, the biasing force can be appropriately adjusted by the voltage regulation.

Description of the reference numerals

1: overflow valve

2: valve body

2 a: fluid inflow path

2 b: fluid outflow passage

2 c: concave part

3: valve seat

4: valve core

7: compression coil spring (force application component)

15: spring seat (bearing part)

22: sensor with a sensor element

Claims

1. An excess flow valve, comprising: a valve body provided with a recess and a fluid inflow passage communicating with the recess; an annular valve seat provided on the valve body; and a valve element housed in the valve body and biased toward the valve seat by a biasing member, the valve element being movable by a fluid pressure in the fluid inflow passage to open and close the fluid inflow passage,

the relief valve is characterized in that it is provided with,

the force application of the force application part can be adjusted,

the urging member includes a sensor for detecting the urging force on at least one end side thereof.

2. The relief valve according to claim 1,

the valve body is biased via a support member that supports the biasing member, and the sensor is interposed between the valve body and the support member.

3. The relief valve according to claim 1 or 2,

the apparatus further includes a transmission unit that transmits information detected by the sensor.