CN219933132U - Foot-operated unloading valve - Google Patents

Abstract

The utility model discloses a foot-operated unloading valve, which comprises a valve body, a first valve seat, a second valve seat, a first valve rod and a second valve rod, wherein one end of the first valve seat is arranged in an inner cavity of the valve body, the other end of the first valve seat is positioned outside the valve body and is in sealing connection with an opening of the inner cavity, one end of the second valve seat is in contact with a stepped surface arranged on the inner wall of the valve body, the other end of the second valve seat is in sealing contact with the first valve seat, a cavity is arranged in the first valve seat along the axial direction of the first valve seat, two annular grooves are arranged on the first valve seat at intervals along the axial direction of the first valve seat, water through holes for communicating the annular grooves with the cavity are formed between each annular groove and the cavity, a high-pressure water source joint and a high-pressure water outlet joint are connected to the side wall of the valve body close to one annular groove of the second valve seat, and a backflow water outlet joint is connected to the side wall of the valve body at the other annular groove. The utility model adopts the secondary pilot valve core structure and the secondary lever structure, can effectively improve the reaction speed of the system, improves the use safety, and saves more labor and is convenient to use.

Description

Foot-operated unloading valve

Technical Field

The utility model belongs to the technical field of unloading valves, and particularly relates to a pedal unloading valve.

Background

The application range of the high-pressure water jet cleaning technology is quite wide, and the high-pressure water jet cleaning device generally comprises a high-pressure nozzle, a conveying pipeline, an unloading valve, a water tank and a high-pressure pump, wherein the high-pressure pump is used for pumping clear water in the water tank and pressurizing the clear water in a normal use state, and jetting high-pressure water through the conveying pipeline and the high-pressure nozzle to perform jet cleaning; when the high-pressure water is in a to-be-used state, the high-pressure water discharged by the high-pressure pump flows back to the water tank through the unloading valve connected to the conveying pipeline, so that the high-pressure pump is in an idle running state, and further the high-pressure water pump is prevented from being frequently started and stopped, the pressure stability of the system is ensured, and the unloading valve can realize the function of water flow reversing.

At present, most of unloading valves used under the conditions of explosion-proof areas and insufficient field conditions are manual unloading valves, and in the high-pressure water jet cleaning process, operators usually need to hold a cleaning gun provided with a nozzle to clean equipment, at the moment, the unloading valves are controlled in a manual mode, and the manual mode overcomes the pressure of high-pressure water to realize water flow reversing, so that the manual type unloading valve is more laborious and inconvenient to use. In addition, when the unloading valve in the prior art is manually adjusted, the system response speed is difficult to cope with emergency situations that sudden unexpected needs of rapid pressure relief on a working site, and the safety and the reliability are poor. Therefore, there is a need to improve the existing manual unloading valve structure to provide a pedal unloading valve which is labor-saving in use, convenient to operate and capable of improving the reaction speed of the system.

Disclosure of Invention

Aiming at the defects in the background technology, the utility model provides a pedal unloading valve which is labor-saving in use and convenient to operate.

In order to achieve the above purpose, the technical solution of the present utility model is as follows:

a foot operated unloading valve, characterized in that: including valve body, first disk seat, second disk seat, first valve rod and second valve rod, first disk seat one end is located in the inner chamber of valve body, and the other end is located the valve body outside and with the opening part sealing connection of inner chamber, second disk seat one end is inconsistent with the step surface of establishing on the valve body inner wall, and the other end is connected with first disk seat sealing contact, first disk seat is inside to be equipped with the cavity along its axial, be equipped with two ring channels along its axis direction interval on the first disk seat, every all be equipped with the water hole with its intercommunication between ring channel and the cavity, be connected with high-pressure water source joint and high-pressure water outlet joint on the valve body lateral wall that is close to a ring channel department of second disk seat, be connected with backward flow water outlet joint on the valve body lateral wall of another ring channel department, the cavity is by first cavity, second cavity and third cavity's internal diameter is less than the internal diameter of second cavity, and be less than the external diameter that the second disk seat is close to first one end, first valve rod one end and third cavity sliding connection are located along its axial through-hole, the internal diameter of second valve seat is close to the second valve rod is close to the internal diameter of first valve rod, the second valve rod is close to the second valve rod is equipped with the external diameter of first valve rod and the axial through-hole is connected with the valve rod, the inside the second valve rod is connected with the through-hole.

Preferably, the first valve seat is of a sectional structure and is formed by movably connecting a first valve seat A and a first valve seat B, one annular groove is arranged on the first valve seat A, the other annular groove is arranged on the first valve seat B, the first valve seat A is in threaded connection with the side wall of the inner cavity of the valve body, two sealing gaskets are arranged between the first valve seat B and the side wall of the inner cavity of the valve body, and the two sealing gaskets are positioned on two sides of the annular groove on the first valve seat B.

Preferably, a positioning groove is formed in one end of the first valve seat A, a positioning block is arranged at one end of the first valve seat B, and the positioning block is connected with the positioning groove in a matched mode.

Preferably, the pedal lever driving mechanism comprises a shell, a swing arm, a connecting rod and a pedal, one end of the swing arm is rotationally connected with a first positioning shaft arranged on the inner wall of the shell, the other end of the swing arm is hinged with one end of the connecting rod, a second positioning shaft rotationally connected with the inner wall of the shell is arranged on the pedal, one end of the pedal, which is close to the second positioning shaft, is hinged with the other end of the connecting rod, the other end of the pedal extends out of the shell and is provided with a pedal part, a torsion spring is connected between the second positioning shaft and a positioning rod arranged on the inner wall of the shell and close to one end of the second valve rod, which is far away from the second valve seat, is abutted against one end of the swing arm, which is close to the connecting rod, a limiting component for limiting the displacement travel of the second valve rod is arranged in the inner cavity of the valve body, and a limiting spring is sleeved on the second valve rod and is positioned between the second valve seat and the limiting component.

Preferably, the limiting assembly comprises a limiting boss arranged on the second valve rod and a limiting groove arranged on the side wall of the inner cavity of the valve body, the limiting spring is arranged between the second valve seat and the limiting boss, a clamping ring is embedded in the limiting groove and is arranged between the limiting boss and the swing arm and matched with the limiting boss.

Preferably, the bottom of the shell is provided with a base which is convenient for combining and connecting the base with the valve body, and the base is assembled and connected with the shell and the valve body by bolts or screws.

Preferably, the base is connected with an adjusting screw rod for adjusting the rotation angle range of the pedal along the second positioning shaft in a threaded manner, and the adjusting screw rod is located right below the pedal part and is matched with the bottom end surface of the pedal part.

Preferably, the base is connected with an inverted U-shaped protective cover, and the inverted U-shaped protective cover is positioned right above the pedal part.

Preferably, the inverted U-shaped protective cover extends to the upper part of one end of the valve body far away from the pedal part, and is provided with an observation port.

Preferably, the number of the backflow water outlet connectors is two, and the two backflow water outlet connectors are symmetrically distributed on two sides of the valve body.

Compared with the prior art, the utility model has the following beneficial effects:

(1) The utility model utilizes the first valve rod, the second valve rod, the first valve seat and the second valve seat to form a secondary pilot valve core structure, thereby not only effectively improving the reaction speed of the system to meet the emergency requirement of rapidly releasing pressure in response to sudden accidents on a working site, improving the safety, but also facilitating the control of an operator on the first valve rod, reducing the effort required by overcoming the pressure of high-pressure water to realize water flow reversing and saving more labor in use;

(2) The secondary lever structure composed of the swing arm, the connecting rod, the pedal and other parts can realize the purpose of applying smaller external force to the pedal to output larger thrust to the second valve rod, effectively reduce the effort required by an operator to control the unloading valve and is more convenient to use.

Drawings

Other features, objects and advantages of the present utility model will become more apparent upon reading of the detailed description of non-limiting embodiments, made with reference to the following drawings.

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is a schematic view of the internal structure of the protective cover of the present utility model;

FIG. 3 is a schematic cross-sectional view of the present utility model;

FIG. 4 is a schematic cross-sectional view of a valve body according to the present utility model;

FIG. 5 is a schematic view of the internal structure of the valve body and the housing of the present utility model;

FIG. 6 is a schematic view of the connecting structure of the components inside the valve body of the present utility model;

FIG. 7 is a schematic diagram showing the split structure of a first valve seat A and a first valve seat B according to the present utility model;

FIG. 8 is a schematic view of a pedal lever driving mechanism according to the present utility model;

in the figure: 1. valve body, 2, first valve seat, 201, first valve seat a,2011, constant head tank, 202, first valve seat B,2021, positioning block, 3, second valve seat, 4, first valve rod, 5, second valve rod, 6, inner cavity, 7, cavity, 701, first cavity, 702, second cavity, 703, third cavity, 8, annular groove, 9, water passing hole, 10, high-pressure water source joint, 11, high-pressure water outlet joint, 12, backflow water outlet joint, 13, through hole, 14, inserting groove, 15, shell, 16, swing arm, 17, connecting rod, 18, pedal, 1801, pedal, 19, first positioning shaft, 20, second positioning shaft, 21, torsion spring, 22, limit spring, 23, limit boss, 24, limit groove, 25, collar, 26, base, 27, bolt or screw, 28, adjusting screw, 29, inverted U-shaped shield, 30, observation port, 31, sealing gasket, 32, positioning rod.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments.

In the description of the present utility model, it should be understood that the terms "middle," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate describing the present utility model and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

In the present utility model, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," "secured," and the like are to be construed broadly and may be, for example, fixedly connected or detachably connected; may be a mechanical connection; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

As shown in fig. 1, 2 and 3, a foot-operated unloading valve comprises a valve body 1, a first valve seat 2, a second valve seat 3, a first valve rod 4 and a second valve rod 5, wherein one end of the first valve seat is arranged in an inner cavity 6 of the valve body, the other end of the first valve seat is positioned outside the valve body and is in sealing connection with an opening of the inner cavity, the outer diameter of one end of the first valve seat positioned outside the valve body is larger than the inner diameter of the inner cavity, a sealing gasket 31 is arranged between the first valve seat and the side wall of the inner cavity of the valve body, one end of the second valve seat is in contact with a stepped surface arranged on the inner wall of the valve body, the other end of the second valve seat is in sealing contact with the first valve seat, a cavity 7 is arranged inside the first valve seat along the axial direction of the first valve seat, two annular grooves 8 are arranged on the first valve seat along the axial direction of the first valve seat at intervals, the water passing holes 9 for communicating the annular grooves with the cavities are formed in the position, close to the second valve seat, of the side wall of the valve body at one annular groove is connected with the high-pressure water source connector 10 and the high-pressure water outlet connector 11, the side wall of the valve body at the other annular groove is connected with the backflow water outlet connector 12, high-pressure water entering the inner cavity of the valve body through the high-pressure water source connector can flow out through the high-pressure water outlet connector and be connected with the high-pressure cleaning nozzle, and also can flow out through the cavities through the backflow water outlet connector and be used for backflow of the high-pressure water into the high-pressure water tank, the water flow direction is regulated by controlling the position of the first valve rod, in the embodiment, the backflow water outlet connectors are symmetrically distributed on two sides of the valve body, and the use is safer.

As shown in fig. 3 and 4, the cavity is formed by sequentially connecting a first cavity 701, a second cavity 702 and a third cavity 703, the inner diameter of the third cavity is smaller than the inner diameter of the second cavity and smaller than the outer diameter of the second valve seat, which is close to one end of the first valve seat, one end of the first valve rod is slidably connected with the third cavity, the other end of the first valve rod is arranged in the second cavity, the diameter of the first valve rod is larger than the inner diameter of the first cavity, which is close to one end of the second cavity, when the first valve rod moves to the end of the first cavity, sealing between the first cavity and the second cavity can be realized, high-pressure water is blocked from flowing to the backflow water joint, when the first valve rod is separated from the first cavity, high-pressure water can flow into the first cavity and flow out from the backflow water joint, one end of the second valve rod penetrates the second valve seat and is in conflict with the first valve rod, the other end extends to the outside of the second valve seat and is connected with a pedal lever driving mechanism (shown in figure 5) capable of driving the second valve seat to axially slide along the valve body, a through hole 13 axially distributed along the first valve rod is arranged in the first valve rod, a plugging slot 14 communicated with the through hole is arranged in the middle part of one end of the first valve rod, which is close to the second valve rod, the inner diameter of the plugging slot is smaller than that of the through hole, the first valve rod and the second valve rod are in split design, when the second valve rod moves towards the direction close to the first valve rod, the first valve rod can be driven to move towards the first cavity, when the second valve rod moves towards the direction far away from the first valve rod under the action of a limiting spring, the second valve rod is separated from the first valve rod, the second valve rod and the first valve rod form a secondary pilot valve core structure, the reaction speed of the system can be improved, the emergency requirement for rapidly relieving sudden unexpected demands on working sites can be met, the safety is improved, the control of an operator on the first valve rod can be facilitated, the force required by overcoming the pressure of high-pressure water to realize water flow reversing is reduced, the use is more labor-saving, meanwhile, the secondary pilot valve core structure is adopted, the displacement of water flow can be ensured to be improved in unit time in the same proportion.

As shown in fig. 4, fig. 6 and fig. 7, the first valve seat is of a sectional structure and is formed by movably connecting a first valve seat a201 and a first valve seat B202, one annular groove is arranged on the first valve seat a, the other annular groove is arranged on the first valve seat B, the first valve seat a is in threaded connection with the side wall of the inner cavity of the valve body, two sealing gaskets 31 are arranged between the first valve seat B and the side wall of the inner cavity of the valve body, the two sealing gaskets are positioned on two sides of the annular groove on the first valve seat B, high-pressure water cannot permeate through a gap between the first valve seat B and the valve body when the first valve rod is tightly attached to the first cavity, a positioning groove 2011 is arranged at one end of the first valve seat a, a positioning block 2021 is arranged at one end of the first valve seat B, the positioning block is connected with the positioning groove in a matched manner, the disassembly and the maintenance are convenient, and the manufacturing and using costs are reduced.

As shown in fig. 3, fig. 5 and fig. 8, the pedal lever driving mechanism includes casing 15, swing arm 16, connecting rod 17, footboard 18, swing arm one end rotates with the first locating shaft 19 of locating on the shells inner wall to be connected, the other end is articulated with connecting rod one end, be equipped with on the footboard and rotate the second locating shaft 20 of being connected with shells inner wall, the one end that the footboard is close to second locating shaft is articulated with the other end of connecting rod, the footboard other end extends to the casing outside and is equipped with pedal portion 1801, be connected with torsional spring 21 between the locating lever 32 that the second locating shaft is close to second valve rod one end on shells inner wall, the one end that the second valve rod kept away from the second disk seat is inconsistent with the one end that the swing arm is close to the connecting rod, be equipped with the spacing subassembly of restriction second valve rod displacement stroke in the valve body inner chamber, the cover is equipped with spacing spring 22 on the second valve rod, spacing spring is located between second disk seat and the spacing subassembly, combine the spacing subassembly to be shown in fig. 4 and fig. 6, spacing spring is located between second disk seat and the spacing groove, be equipped with collar 25 in the spacing groove, be located between spacing disk seat and the spacing boss, and with the lever, and the pedal lever is close to the mutual effect is compared with the lever, the pedal lever structure has reduced the efficiency and can be realized, the more and the pedal lever structure is more convenient to the cost is reduced. When an operator steps on the pedal part of the pedal by foot, the pedal part moves downwards, the other end of the pedal drives the connecting rod to swing, and the connecting rod drives the swing arm to rotate so as to move the second valve rod towards the direction close to the first valve rod; when an operator stops stepping, the limiting spring pushes the limiting boss on the second valve rod to move in the direction away from the first valve rod, so that the swing arm, the connecting rod and the pedal are reset.

As shown in fig. 1, 2, 3 and 5, the bottom of the shell is provided with a base 26 which is convenient for combining and connecting the base with the valve body, and the base is assembled and connected with the shell and the valve body by bolts or screws 27, and the base is also convenient for fixing and installing the utility model. The screw thread is connected with the adjusting screw 28 that is used for adjusting footboard along second locating shaft rotation angle scope on the base, and adjusting screw is located pedal portion under and mutually support with pedal portion's bottom face, can adjust according to operating personnel's actual conditions, avoids the too big with the power, increases the impact of first valve rod to first cavity, reduction in service life of equipment. As shown in fig. 1, an inverted U-shaped protective cover 29 is connected to the base, and is located right above the pedal portion, so as to prevent foreign objects from falling on the feet of an operator or the pedal portion of the pedal, and to cause personal injury or influence the normal use of the pedal unloading valve. The inverted U-shaped protective cover extends to the upper part of one end of the valve body far away from the pedal part and is provided with an observation port 30, so that the service condition of the unloading valve can be observed conveniently.

The working principle of the utility model is as follows:

as shown in fig. 1 to 8, the present utility model is characterized in that a high-pressure water source connector 10 is connected with a high-pressure water source, a high-pressure water outlet connector 11 is connected with a high-pressure nozzle which needs to be used, and a backflow water outlet connector 12 can be connected with a water tank of the high-pressure water source before the present utility model is used. When the high-pressure water supply valve is used, the first valve rod 4 is separated from the first cavity 701 of the first valve seat 2, at the moment, the first cavity 701 is communicated with the second cavity 702, and the water outlet of the nozzle is smaller than the water outlet backflow joint 12, so that the water pressure between the high-pressure water outlet joint 11 and the nozzle is larger than the water pressure between the water outlet backflow joint 12 and the high-pressure water tank, and therefore, after high-pressure water flowing into the valve body 1 from the high-pressure water source joint 10 enters the second cavity 702, most of the high-pressure water flows into the water outlet backflow joint 12 through the first cavity 701 and finally flows back to the high-pressure water tank to be convenient to reuse, and a very small amount of water flows out from the high-pressure water outlet joint 11 and the outflow water cannot form high pressure and destructive power; when high-pressure water is required to be output, an operator can push the swing arm 16 to extrude the second valve rod 5 and push the second valve rod 5 to move towards the direction close to the first valve rod 4 by stepping the pedal part 1801 of the pedal 18 through a secondary lever structure until the first valve rod 4 is driven to be in contact with the end part of the first cavity 701, the joint of the first cavity 701 and the second cavity 702 is blocked, and as two sealing gaskets 31 are arranged on two sides of the annular groove 8 at the second cavity 702, the sealing between the first valve seat B202 and the valve body 1 is realized, the high-pressure water can only flow out through the high-pressure water connector 11 and is finally sprayed out through the nozzle, and the water sprayed out by the nozzle is high-pressure water and has extremely strong destructive power and can be used for cleaning. Meanwhile, high-pressure water flows to one end of the second valve rod 5 through a gap between the first valve rod 4 and the side wall of the third cavity 703 and finally flows into the plugging groove 14, because the second valve rod 5 plugs the through hole 13 of the first valve rod 4, water in the plugging groove 14 cannot circulate, the water pressure in the plugging groove 14 is the same as the water pressure in the second cavity 702, and an operator only needs to provide small force to tightly press the first valve rod 4 against the end part of the first cavity 701. When the cleaning work is completed and the output of high-pressure water is required to be stopped, a worker releases the pedal 18, the second valve rod 5 moves to one side of the swing arm 16 under the action of the limiting spring 22, the swing arm 16, the connecting rod 17 and the pedal 18 are driven to reset, meanwhile, the second valve rod 5 is separated from the first valve rod 4, water in the plug-in groove 14 instantaneously flows to the first cavity 701 from the through hole 13 in the first valve rod 4, at the moment, the water pressure in the plug-in groove 14 is rapidly reduced, the high-pressure water in the second cavity 702 pushes the first valve rod 4 to move to one end of the second valve rod 5, the first cavity 701 is communicated with the second cavity 702 again, and the high-pressure water flows back to the high-pressure water tank through the first cavity 701 and the backflow water outlet joint 12.

While the fundamental and principal features of the utility model and advantages of the utility model have been shown and described, it will be apparent to those skilled in the art that the utility model is not limited to the details of the foregoing exemplary embodiments, but may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the utility model being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (10)

1. A foot operated unloading valve, characterized in that: including valve body, first disk seat, second disk seat, first valve rod and second valve rod, first disk seat one end is located in the inner chamber of valve body, and the other end is located the valve body outside and with the opening part sealing connection of inner chamber, second disk seat one end is inconsistent with the step surface of establishing on the valve body inner wall, and the other end is connected with first disk seat sealing contact, first disk seat is inside to be equipped with the cavity along its axial, be equipped with two ring channels along its axis direction interval on the first disk seat, every all be equipped with the water hole with its intercommunication between ring channel and the cavity, be connected with high-pressure water source joint and high-pressure water outlet joint on the valve body lateral wall that is close to a ring channel department of second disk seat, be connected with backward flow water outlet joint on the valve body lateral wall of another ring channel department, the cavity is by first cavity, second cavity and third cavity's internal diameter is less than the internal diameter of second cavity, and be less than the external diameter that the second disk seat is close to first one end, first valve rod one end and third cavity sliding connection are located along its axial through-hole, the internal diameter of second valve seat is close to the second valve rod is close to the internal diameter of first valve rod, the second valve rod is close to the second valve rod is equipped with the external diameter of first valve rod and the axial through-hole is connected with the valve rod, the inside the second valve rod is connected with the through-hole.

2. A foot operated unloader valve as set forth in claim 1 wherein: the first valve seat is of a sectional structure and is formed by movably connecting a first valve seat A and a first valve seat B, one annular groove is formed in the first valve seat A, the other annular groove is formed in the first valve seat B, the first valve seat A is in threaded connection with the side wall of the inner cavity of the valve body, two sealing gaskets are arranged between the first valve seat B and the side wall of the inner cavity of the valve body, and the two sealing gaskets are located on two sides of the annular groove on the first valve seat B.

3. A foot operated unloader valve as set forth in claim 2 wherein: one end of the first valve seat A is provided with a positioning groove, one end of the first valve seat B is provided with a positioning block, and the positioning block is connected with the positioning groove in a matched mode.

4. A foot operated unloader valve as set forth in claim 1 wherein: the pedal lever driving mechanism comprises a shell, a swing arm, a connecting rod and a pedal, wherein one end of the swing arm is rotationally connected with a first positioning shaft arranged on the inner wall of the shell, the other end of the swing arm is hinged with one end of the connecting rod, a second positioning shaft rotationally connected with the inner wall of the shell is arranged on the pedal, one end of the pedal, which is close to the second positioning shaft, is hinged with the other end of the connecting rod, the other end of the pedal extends out of the shell and is provided with a pedal part, a torsion spring is connected between the second positioning shaft and a positioning rod which is arranged on the inner wall of the shell and is close to one end of the second valve rod, which is far away from the second valve seat, is abutted against one end of the swing arm, which is close to the connecting rod, a limiting component for limiting the displacement travel of the second valve rod is arranged in an inner cavity of the valve body, and a limiting spring is sleeved on the second valve rod and is positioned between the second valve seat and the limiting component.

5. A foot operated unloader valve as set forth in claim 4 wherein: the limiting assembly comprises a limiting boss arranged on the second valve rod and a limiting groove arranged on the side wall of the inner cavity of the valve body, the limiting spring is arranged between the second valve seat and the limiting boss, a clamping ring is embedded in the limiting groove, and the clamping ring is arranged between the limiting boss and the swing arm and is matched with the limiting boss.

6. A foot operated unloader valve as set forth in claim 4 wherein: the bottom of the shell is provided with a base which is convenient for combining and connecting the base with the valve body, and the base is assembled and connected with the shell and the valve body by bolts or screws.

7. A foot operated unloader valve as set forth in claim 6 wherein: the base is connected with an adjusting screw rod used for adjusting the rotation angle range of the pedal along the second positioning shaft in a threaded manner, and the adjusting screw rod is located right below the pedal portion and is matched with the bottom end face of the pedal portion.

8. A foot operated unloader valve as set forth in claim 6 wherein: the base is connected with an inverted U-shaped protective cover, and the inverted U-shaped protective cover is positioned right above the pedal part.

9. A foot operated unloader valve as set forth in claim 8 wherein: the inverted U-shaped protective cover extends to the upper part of one end of the valve body far away from the pedal part and is provided with an observation port.

10. A foot operated unloader valve as set forth in claim 1 wherein: the number of the backflow water outlet connectors is two, and the two backflow water outlet connectors are symmetrically distributed on two sides of the valve body.