CN218845235U - Novel freely-adjustable pressure limiting valve - Google Patents

Abstract

The utility model discloses a novel freely adjustable pressure limiting valve, which comprises: a shell, which has a water outlet end and a water inlet end; There is a pressure limiting hole connecting the water inlet and the water outlet; the piston moving part is arranged between the water inlet and the water outlet in the housing, and when the piston moving part moves to the water inlet to the limit, the head of the piston moving part Resist against the pressure limiting seat to block the pressure limiting hole; the adjustment seat, its movement is set on the outer periphery of the piston moving part; the elastic part, which is sandwiched between the adjustment seat and the tail of the piston moving part, when the water pressure at the water outlet increases, the piston will When the moving part moves toward the water inlet, the elastic part provides the piston moving part with a force toward the water outlet. The utility model can realize the pressure limiting effect of different pressure levels, and the adjustment is convenient and quick, and the practicability is strong.

Description

New freely adjustable pressure limiting valve

technical field

The utility model relates to the technical field of fluid control components, in particular to a novel freely adjustable pressure limiting valve.

Background technique

The demand for various types of water in the daily water supply system is constantly increasing, and the water supply pressure of the daily water supply system is often relatively high. The use pressure of household water, industrial water, and boiler systems at the household end does not need to be too high, and the water supply pressure is high. It will cause damage to household water appliances, industrial equipment, boiler facilities or pipelines, so installing a pressure limiting device at the entrance of the household is a safety protection measure, which can ensure the safe use of household water appliances, industrial equipment, boiler facilities, pipelines There will be no pipe burst phenomenon. With the improvement of people's safety awareness, the use of pressure limiting devices is becoming more and more extensive. At present, the pressure output of the commonly used specifications in the domestic and foreign markets is 350kPa, 500kPa, and 600kPa. The pressure limiting valve of each specification can only output a single pressure, and the output pressure cannot be adjusted freely according to the actual use needs. If the output pressure needs to be changed, the pressure limiting valve needs to be replaced, which is time-consuming and laborious.

Utility model content

An object of the present invention is to solve at least the above-mentioned problems and provide at least the advantages which will be described later.

Another purpose of this utility model is to provide a new type of freely adjustable pressure limiting valve, which can flexibly adjust the elastic force of the elastic member surrounding the piston moving part by setting a movable adjustment seat to change the direction of the piston moving part. The magnitude of the force provided in the direction of the water outlet can further change the pressure that the piston moving part can bear in the direction of the water inlet provided by the water pressure of the water outlet when the piston is in balance, so as to achieve the purpose of changing the water pressure of the water outlet.

In order to achieve these objects and other advantages according to the present invention, a novel freely adjustable pressure limiting valve is provided, comprising:

a housing having a water outlet and an inlet;

A pressure limiting seat, which is arranged in the housing and is sealed and detachably connected with the housing, and the pressure limiting seat is provided with a pressure limiting hole communicating with the water inlet end and the water outlet end;

The piston moving part is arranged between the water inlet end and the water outlet end in the housing. When the piston moving part moves to the water inlet end to the limit, the head of the piston moving part and the The pressure limiting seat is offset to block the pressure limiting hole;

An adjustment seat, which is arranged on the outer periphery of the moving part of the piston;

An elastic piece, which is sandwiched between the adjustment seat and the tail of the piston moving piece, when the water pressure at the water outlet increases to move the piston moving piece to the water inlet, the elastic piece is The piston moving part provides a force in the direction of the water outlet.

Preferably, in the novel freely adjustable pressure limiting valve, an adjustment ring is provided on the outer circumference of the housing, and a plurality of adjustment holes are provided on the uniform ring on the housing; the adjustment seat includes an annular component, A plurality of adjustment blocks are provided at one end of the ring member and protrude outward, and a limit block is provided at the other end of the ring member and protrude inward; the plurality of adjustment blocks pass through their corresponding adjustment holes and The adjustment ring is threaded, and the elastic member is sandwiched between the limit block and the tail of the piston moving part. When the adjustment ring is rotated, the adjustment seat is driven toward the water outlet or the The water inlet end moves in the direction to squeeze the elastic member to different degrees, so as to realize the pressure limitation of different pressure levels.

Preferably, in the novel freely adjustable pressure limiting valve, the housing includes a detachably connected water outlet housing and a water inlet housing, the outer periphery of the water outlet housing is provided with a first boss, and the outer circumference of the water inlet housing is A second boss is arranged on the periphery, and the adjustment ring is clamped between the first boss and the second boss.

Preferably, in the novel freely adjustable pressure limiting valve, the elastic member is a spring, and the spring is sleeved on the outer circumference of the piston moving part and clamped between the limiting block and the piston moving part between the tails.

Preferably, in the novel freely adjustable pressure limiting valve, the inside of the pressure limiting seat is open and one end is sealed, the pressure limiting hole is provided on the side wall of the pressure limiting seat, and the piston moving part is provided with There is a through hole connecting the water inlet, the pressure limiting hole, and the water outlet. The head of the piston moving part is inserted into the pressure limiting seat for sliding sealing and when the piston moving part moves toward the When the water inlet end moves to the limit, the head of the piston moving part is in contact with the sealing end of the pressure limiting seat to block the pressure limiting hole and the through hole, and the tail of the piston moving part is in contact with the casing. Slip seal connection.

Preferably, in the novel freely adjustable pressure limiting valve, the piston moving part includes:

The piston is provided with the through hole, and the head of the piston is inserted into the pressure limiting seat for sliding sealing. When the moving part of the piston moves to the water inlet end to the limit, the head of the piston part against the sealing end of the pressure limiting seat to block the pressure limiting hole and the through hole;

A locking piece is arranged around the outer circumference of the piston and is sealingly and detachably connected to the tail of the piston, and the locking piece is in sliding and sealing connection with the housing.

Preferably, in the novel freely adjustable pressure limiting valve, seals are provided at the contact surface between the inner wall of the housing and the locking member, and at the contact surface between the piston and the inner wall of the pressure limiting seat. .

Preferably, in the novel freely adjustable pressure limiting valve, the outer wall of the head of the piston is provided with an inclined surface.

Preferably, in the novel freely adjustable pressure limiting valve, the pressure limiting seat includes:

The main body of the pressure limiting seat is open inside and open at both ends, and the pressure limiting hole is provided on the side wall of the main body of the pressure limiting seat;

A sealing plug is sealed and detachably connected to one end of the pressure limiting seat body.

Preferably, in the novel freely adjustable pressure limiting valve, an inner wall step is provided in the housing, and when the piston moving part moves to the water outlet to the limit, the tail of the piston moving part and the housing The inner wall steps of the body offset each other.

The utility model at least includes the following beneficial effects: the new freely adjustable pressure limiting valve of the utility model can freely adjust the output pressure according to the actual use, and is a general-purpose pressure limiting valve covering various specifications such as 350kPa, 500kPa, 600kPa, etc. , suitable for different places with different output pressure requirements, by moving the adjustment seat to different positions corresponding to different positions to adjust and change the elastic force of the elastic member, the pressure limiting effect of different pressure levels can be realized; the utility model is convenient and fast to adjust and easy to use Flexible and practical.

Other advantages, objectives and features of the utility model will partly be embodied through the following description, and partly will be understood by those skilled in the art through the research and practice of the utility model.

Description of drawings

Fig. 1 is a schematic cross-sectional structure diagram of a new freely adjustable pressure limiting valve in one of the technical solutions of the present invention;

Fig. 2 is a perspective view of a novel free-adjusting pressure limiting valve in one of the technical solutions of the utility model;

Fig. 3 is a structural schematic diagram of the adjusting seat in one of the technical solutions of the utility model;

Among them, 1-water outlet housing, 2-inner wall step, 3-sealing member, 4-elastic member, 5-adjusting ring, 6-adjusting block, 7-adjusting seat, 8-limiting block, 9-pressure limiting hole, 10-Water inlet housing, 11-Water inlet end, 12-Auxiliary moving block, 13-Seal plug, 14-Pressure limiting seat body, 15-Second boss, 16-Piston, 17-First boss, 18- Locking piece, 19-through hole, 20-water outlet, 21-ring component.

Detailed ways

The utility model will be described in further detail below in conjunction with the accompanying drawings, so that those skilled in the art can implement it by referring to the description.

It should be understood that terms such as "having", "comprising" and "including" used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

It should be noted that the experimental methods described in the following embodiments, if no special instructions, are conventional methods, and the reagents and materials, if no special instructions, can be obtained from commercial sources; in the description of the utility model , It should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "setup" should be understood in a broad sense, for example, they can be fixedly connected, set up, or detachably connected, set up, Or connect and set integrally. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present utility model in specific situations. The terms "landscape", "portrait", "top", "bottom", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", The orientation or positional relationship indicated by "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply the new type of free adjustment pressure Restriction valves or elements must have a particular orientation, be constructed and operate in a particular orientation, and thus should not be construed as limitations on the invention.

In one of the technical solutions, as shown in Figure 1, the utility model provides a new type of freely adjustable pressure limiting valve, including:

a housing having a water outlet 20 and an inlet 11;

A pressure limiting seat, which is arranged in the housing and is sealed and detachably connected with the housing, and the pressure limiting seat is provided with a pressure limiting hole 9 communicating with the water inlet end 11 and the water outlet end 20;

The piston moving part is arranged between the water inlet 11 and the water outlet 20 in the housing. When the piston moving part moves to the water inlet 11 to the limit, the piston moving part The head is against the pressure limiting seat to block the pressure limiting hole 9;

Adjusting seat 7, the movement of which is arranged on the outer periphery of the moving part of the piston;

The elastic member 4 is interposed between the adjustment seat 7 and the tail of the piston moving part. When the water pressure at the water outlet 20 increases to move the piston moving part to the water inlet 11, the The elastic member 4 provides the piston moving member with a force in the direction of the water outlet 20 .

The new freely adjustable pressure limiting valve provided by this technical solution includes a housing with a water inlet 11 and a water outlet 20 and a pressure limiting seat located inside the housing, a piston moving part, an adjusting seat 7, and an elastic member 4, wherein the pressure limiting The seat is sealed and detachably connected with the housing, and the pressure limiting seat is provided with a pressure limiting hole 9, through which the water flow can flow from the water inlet 11 of the housing to the water outlet 20, and the size of the pressure limiting hole 9 can be limited from the inlet The flow rate of the water flow from the water end 11 to the water outlet 20 can change the flow pressure of the water outlet 20. A seal 3 can be arranged between the pressure limiting seat and the housing for sealing. The piston moving part is located between the water outlet 20 and the water inlet 11. And can move to these two ends, the adjusting seat 7 is arranged on the outer circumference of the piston moving part and can move along the moving direction of the piston moving part, the elastic part 4 is sandwiched between the adjusting seat 7 and the tail of the piston moving part, when the water outlet 20 When the water pressure increases and the piston moving part moves toward the water inlet 11, the elastic part 4 is compressed to provide the piston moving part with a force in the direction of the water outlet 20. Adjusting the position of the adjustment seat 7 can change the compression state of the elastic part 4, thereby changing the elasticity Part 4 is the force provided by the piston moving part. When the piston moving part moves to the water inlet 11 to the limit, the head of the piston moving part and the pressure limiting seat will block the pressure limiting hole 9.

The working principle of the new freely adjustable pressure limiting valve provided by this technical solution is: when the water flow at the water outlet 20 of the casing is fully opened, the size of the pressure limiting hole 9 remains unchanged, and the water flow is kept unimpeded; when the water flow at the water outlet 20 of the casing is closed or When the water outlet is reduced, the water pressure at the water outlet 20 increases continuously so that the piston moving part is forced to move toward the water inlet 11, and the pressure limiting hole 9 is continuously reduced, so that the water flow decreases and the pressure at the water outlet 20 is reduced. At the same time, the elastic member 4 compresses Provide force to the direction of the water outlet 20 for the piston moving part, until the piston moving part is balanced and stationary, at this time, the elastic force of the elastic part 4 is the same as the water pressure of the housing water outlet 20; move the adjustment seat 7 along the moving direction of the piston moving part , the compression state of the elastic member 4 can be changed, that is, the force provided by the elastic member 4 for the piston moving member toward the water outlet 20 can be changed, thereby changing the maximum water pressure of the water outlet 20 .

The utility model can preferentially adjust the position of the adjusting seat according to the known limit pressure of the water equipment to be connected at the water outlet, change the compression state of the elastic member, and then limit the maximum water pressure at the water outlet, and then install it between the water equipment and the water supply pipe ; It is also possible to freely adjust the position of the adjustment seat during the use of water, change the compression state of the elastic member, and then change the water pressure at the water outlet to meet the needs of use.

The utility model at least includes the following beneficial effects: the housing of the utility model is sealed and detachably provided with a pressure-limiting seat, and the pressure-limiting seat is provided with a pressure-limiting hole connecting the water inlet and the water outlet, and the housing is provided with a piston moving part, the piston Moving the moving part to the water outlet can change the size of the pressure limiting hole, change the water flow, and then change the pressure at the water outlet; in the utility model, the compression state of the elastic part can be changed by adjusting the position of the adjustment seat, and then the elastic part can be changed into a piston moving part The force provided in the direction of the water outlet can flexibly change the maximum water pressure that the water outlet can withstand.

In another technical solution, as shown in Fig. 1, Fig. 2 and Fig. 3, in the novel freely adjustable pressure limiting valve, an adjusting ring 5 is provided on the outer circumference of the housing, and an even The ring is provided with a plurality of adjustment holes; the adjustment seat 7 includes a ring part 21, a plurality of adjustment blocks 6 arranged at one end of the ring part 21 and protruding outward, and a plurality of adjustment blocks 6 arranged at the other end of the ring part 21 inwardly. A protruding limit block 8; a plurality of the adjustment blocks 6 are threaded through the corresponding adjustment holes and the adjustment ring 5, and the elastic member 4 is sandwiched between the limit block 8 and the piston Between the tails of the moving parts, when the adjusting ring 5 is rotated, the adjusting seat 7 is driven to move toward the water outlet or the water inlet, and the elastic member 4 is squeezed to different degrees to realize Pressure limitation for different pressure levels.

In order to make the limit block move in the adjustment hole, the length of the adjustment hole is greater than the length of the limit block. Rotating the adjusting ring can make the adjusting block move along the moving direction of the piston moving part in the adjusting hole, and then drive the ring part and the limit block to move synchronously with the adjusting block, so as to flexibly change the compression state of the elastic part and realize different levels of pressure limiting ;The adjustment ring is threadedly connected with the adjustment block, which is convenient and flexible to adjust, and the adjustment accuracy is high; the limit block can be ring-shaped and set around the outer periphery of the piston moving part to evenly compress the elastic part, so that the piston moving part is evenly stressed; the adjustment hole can be It is two, which can reduce the processing difficulty of the parts as much as possible and increase the processing efficiency under the condition that the elastic parts are evenly stressed.

In another technical solution, as shown in Figure 1 and Figure 2, in the novel freely adjustable pressure limiting valve, the housing includes a detachably connected water outlet housing 1 and a water inlet housing 10, the water outlet The outer periphery of the housing 1 is provided with a first boss 17, the outer periphery of the water inlet housing 10 is provided with a second boss 15, and the adjustment ring 5 is clamped between the first boss 17 and the second boss 15 . The adjustment ring is clamped between the first boss and the second boss to limit the position of the adjustment ring on the casing, and the casing is divided into a detachable water outlet casing and a water inlet casing to facilitate the adjustment ring and the inside of the casing Parts are overhauled, disassembled and replaced.

In another technical solution, as shown in Figure 1, in the novel freely adjustable pressure limiting valve, the elastic member 4 is a spring, and the spring is sleeved on the outer periphery of the piston moving member and sandwiched between Between the limiting block 8 and the tail of the piston moving part. The spring is a common mechanical part, which is sleeved on the outer periphery of the piston moving part, and can provide uniform force for the piston moving part.

In another technical solution, as shown in Figure 1, in the novel freely adjustable pressure limiting valve, the inside of the pressure limiting seat is open and one end is sealed, and the side wall of the pressure limiting seat is provided with the limiting Pressure hole 9, the piston moving part is provided with a through hole 19 communicating with the water inlet 11, the pressure limiting hole 9, and the water outlet 20, and the head of the piston moving part is inserted into the sliding seal In the pressure limiting seat and when the piston moving part moves to the water inlet end 11 to the limit, the head of the piston moving part will abut against the sealing end of the pressure limiting seat so that the pressure limiting hole 9, the The through hole 19 is blocked, and the tail of the piston moving part is in sliding and sealing connection with the housing.

The pressure limiting seat can be in the shape of a sleeve with one end sealed, and the piston moving part is provided with a through hole through its head and tail. Inside the pressure limiting seat, at the same time, the side wall of the piston moving part moves along the side wall of the pressure limiting seat and the overlapping area increases continuously, so that the pressure limiting hole on the side wall of the pressure limiting seat is gradually blocked by the side wall of the piston moving part. The water channel keeps getting smaller, and when the head of the piston moving part touches the sealing end of the pressure limiting seat, the pressure limiting hole is blocked by the side wall of the piston moving part, and the water inlet of the through hole located at the head of the piston moving part is pressure limited. Block the sealing end of the seat to cut off the water flow channel.

In another technical solution, as shown in Figure 1, in the novel freely adjustable pressure limiting valve, the piston moving part includes:

The piston 16 is provided with the through hole 19, and the head of the piston is inserted into the pressure limiting seat in a sliding seal. When the piston moving part moves to the water inlet end 11 to the limit, the The head of the piston 16 abuts against the sealing end of the pressure limiting seat so that the pressure limiting hole 9 and the through hole 19 are blocked;

The locking member 18 is arranged around the outer circumference of the piston 16 and is sealingly and detachably connected to the tail of the piston 16 , and the locking member 18 is in sliding and sealing connection with the housing.

The piston is provided with a through hole through its head and tail. If the piston is tubular, when the piston moves to the water inlet, the head of the piston will continue to penetrate into the pressure limiting seat, and the side wall of the piston will follow the side wall of the pressure limiting seat. Move and the overlapping area increases continuously, so that the pressure limiting hole located on the side wall of the pressure limiting seat is gradually blocked by the side wall of the piston, so that the water passage becomes smaller and smaller. When the head of the piston touches the sealing end of the pressure limiting seat, the pressure limiting hole The pressure hole is blocked by the side wall of the piston moving part, and the water inlet of the through hole located at the head of the piston is blocked by the sealing end of the pressure limiting seat, cutting off the water flow channel;

The piston and the pressure limiting seat, the locking part and the piston, and the locking part and the housing are all sealed, so that the water flows from the water inlet through the pressure limiting hole, the inside of the pressure limiting seat, and the through hole to the water outlet to prevent seepage. Leakage affects the pressure effect; in order to adapt to different water quality environments, the piston is made of corrosion-resistant stainless steel, and the moving part of the piston is designed as a detachable connection between the piston and the locking part, which is convenient for disassembly and replacement of the piston; a seal is set between the locking part and the piston Make a seal.

In another technical solution, as shown in FIG. 1, in the novel freely adjustable pressure limiting valve, at the contact surface between the inner side wall of the housing and the locking member 18, the piston 16 and the limiting A seal 3 is provided at the contact surface of the inner side wall of the pressure seat. The sealing member can be a sealing ring to prevent water leakage from affecting the pressure effect.

In another technical solution, as shown in FIG. 1 , in the new freely adjustable pressure limiting valve, the outer wall of the head of the piston 16 is provided with an inclined surface. The inclined surface provides guidance for the movement of the piston towards the water inlet.

In another technical solution, as shown in Figure 1, in the novel freely adjustable pressure limiting valve, the pressure limiting seat includes:

The pressure-limiting seat body 14 is open inside and open at both ends, and the pressure-limiting hole 9 is provided on the side wall of the pressure-limiting seat body 14;

A sealing plug 13 is sealed and detachably connected to one end of the pressure limiting seat body 14 .

When the piston moves to the water inlet to the limit, the piston and the sealing plug will be in contact, and the long-term interaction will easily damage the sealing plug. The sealing plug and the pressure limiting seat body can be detachably connected to facilitate the replacement of the sealing plug; when the sealing plug faces away from the pressure limiting seat One end of the opening can be provided with an auxiliary moving block 12 to facilitate the disassembly of the sealing plug. A sealing member is arranged between the sealing plug and the pressure limiting seat body for sealing.

In another technical solution, as shown in Figure 1, in the novel free-adjusting pressure limiting valve, an inner wall step 2 is provided in the housing, when the piston moving part moves to the water outlet 20 to the limit , the tail of the piston moving part is against the inner wall step 2 of the housing. The inner wall step limits the extreme position of the piston moving part when it moves to the water outlet, and prevents the piston moving part from breaking away from the casing when it moves to the water outlet due to the force of water flow or the elastic force of the elastic part.

The number of devices and the scale of processing described here are used to simplify the description of the present invention. Applications, modifications and variations of the present invention will be apparent to those skilled in the art.

Although the embodiment of the present utility model has been disclosed as above, it is not limited to the use listed in the description and the implementation, and it can be applied to various fields suitable for the present utility model. For those familiar with the art, Further modifications can be readily effected, so the invention is not limited to the specific details and examples shown and described herein without departing from the general concept defined by the claims and their equivalents.

Claims (10)

1. A new type of freely adjustable pressure limiting valve, characterized in that it includes: a housing having a water outlet and an inlet; A pressure limiting seat, which is arranged in the housing and is sealed and detachably connected with the housing, and the pressure limiting seat is provided with a pressure limiting hole communicating with the water inlet end and the water outlet end; The piston moving part is arranged between the water inlet end and the water outlet end in the housing. When the piston moving part moves to the water inlet end to the limit, the head of the piston moving part and the The pressure limiting seat is offset to block the pressure limiting hole; An adjustment seat, which is arranged on the outer periphery of the moving part of the piston; An elastic piece, which is sandwiched between the adjustment seat and the tail of the piston moving piece, when the water pressure at the water outlet increases to move the piston moving piece to the water inlet, the elastic piece is The piston moving part provides a force in the direction of the water outlet. 2. The novel freely adjustable pressure limiting valve according to claim 1, wherein an adjusting ring is provided on the outer circumference of the housing, and a plurality of adjusting holes are provided on the uniform ring on the housing; the adjusting seat It includes a ring-shaped part, a plurality of adjusting blocks arranged at one end of the ring-shaped part and protruding outward, and a limit block arranged at the other end of the ring-shaped part protruding inward; a plurality of the adjusting blocks pass through their corresponding The adjustment hole is threadedly connected with the adjustment ring, the elastic member is clamped between the limit block and the tail of the piston moving part, when the adjustment ring is rotated, the adjustment seat is driven toward the The water outlet end or the water inlet end moves in a direction to squeeze the elastic member to different degrees, so as to realize pressure limitation at different pressure levels. 3. The novel free-adjusting pressure limiting valve according to claim 2, wherein the housing includes a detachably connected water outlet housing and a water inlet housing, and a first boss is arranged on the outer periphery of the water outlet housing, The outer periphery of the water inlet housing is provided with a second boss, and the adjustment ring is clamped between the first boss and the second boss. 4. The novel freely adjustable pressure limiting valve according to claim 2, wherein the elastic member is a spring, and the spring is sleeved on the outer periphery of the piston moving member and clamped between the limit block and the between the tails of the moving parts of the piston. 5. The novel freely adjustable pressure limiting valve according to claim 1, characterized in that, the inside of the pressure limiting seat is open and one end is sealed, the side wall of the pressure limiting seat is provided with the pressure limiting hole, the The piston moving part is provided with a through hole communicating with the water inlet, the pressure limiting hole and the water outlet, and the head of the piston moving part is inserted into the pressure limiting seat for sliding sealing and when the piston When the moving part moves to the water inlet end to the limit, the head of the piston moving part contacts the sealing end of the pressure limiting seat to block the pressure limiting hole and the through hole, and the tail of the piston moving part Sliding and sealing connection with the housing. 6. The novel freely adjustable pressure limiting valve according to claim 5, wherein said piston moving part comprises: The piston is provided with the through hole, and the head of the piston is inserted into the pressure limiting seat for sliding sealing. When the moving part of the piston moves to the water inlet end to the limit, the head of the piston part against the sealing end of the pressure limiting seat to block the pressure limiting hole and the through hole; A locking piece is arranged around the outer circumference of the piston and is sealingly and detachably connected to the tail of the piston, and the locking piece is in sliding and sealing connection with the housing. 7. The novel freely adjustable pressure limiting valve according to claim 6, characterized in that, the contact surface between the inner wall of the housing and the locking member, the contact surface between the piston and the inner wall of the pressure limiting seat Both are provided with seals. 8. The novel freely adjustable pressure limiting valve according to claim 6, characterized in that the outer wall of the head of the piston is provided with an inclined surface. 9. The novel freely adjustable pressure limiting valve according to claim 5, wherein the pressure limiting seat comprises: The main body of the pressure limiting seat is open inside and open at both ends, and the pressure limiting hole is provided on the side wall of the main body of the pressure limiting seat; A sealing plug is sealed and detachably connected to one end of the pressure limiting seat body. 10. The novel free-adjusting pressure limiting valve according to claim 1, wherein an inner wall step is provided in the housing, and when the piston moving part moves to the water outlet end to the limit, the piston moving part The tail part is against the inner wall step of the housing.

Images