JP2562919Y2 - Unload valve - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unload valve provided in a washing machine, a sprayer, and the like, and more particularly, to an unload valve capable of adjusting an unload time.

[0002]

2. Description of the Related Art In a washing machine, a chemical spraying machine, or the like, a liquid such as water is pressure-fed from a pump to a trigger nozzle held by an operator via a hose, and the operator manually operates a trigger of the trigger nozzle. The ejection of liquid from the tip of the trigger nozzle is controlled. During the closing of the trigger nozzle, no liquid is consumed and no pumping of the liquid through the hose is necessary, so the unload valve is connected to the discharge side of the pump,
When the trigger nozzle is opened or closed, the pump discharge side is opened while the trigger nozzle is closed to reduce the power loss of the pump.

[0003] In a general structure of a conventional unload valve,
As the trigger nozzle is closed, the check valve in the unload valve closes, sealing the liquid at the outlet side, increasing the hydraulic pressure at the outlet, and the piston increasing the hydraulic pressure at the outlet. The unloading valve body is displaced integrally with the unloading valve body against the urging member, and the unloading valve body is switched from the loading position to the unloading position to discharge the liquid from the excess liquid port. . Conventional unload valve (Example: Japanese Utility Model Laid-Open No. 1-139179)
In FIG. 2 (FIG. 2), the axial position of the piston is fixed to the valve stem connecting the piston to the unloading valve body, and it is difficult to adjust the axial position. Further, in order to transmit the hydraulic pressure at the outlet to the end face of the piston, the piston guide into which the piston is inserted on the inner peripheral side has a plurality of through holes that allow the inner and outer circumferences to communicate with each other at the end on the side of the communication path to the outlet. Has been processed.

[0004]

When the trigger nozzle is closed, the unloading valve element of the unloading valve is switched to the unloading position, but the liquid leaks from the hose connection and the pressure at the check valve. Due to the leak, the hydraulic pressure at the outlet decreases, and the unloading valve body may switch from the unload position to the load position again (hunting). The unload time affects the life of the pump and the like. In the conventional unload valve, it is difficult to adjust the lift amount (= the amount of movement in the axial direction) of the piston and the unloading valve body, and therefore, it is also difficult to adjust the unload time during hunting or the like. In addition, since a through hole that communicates the inner and outer circumferences is required at the end of the piston guide, processing of the piston guide becomes complicated, and in order to ensure that the hydraulic pressure from the through hole acts on the end face of the piston, So that the piston does not block the through hole
The length of the piston guide increases.

It is an object of the invention of claim 1 to provide an unload valve whose unload time can be appropriately adjusted.
An object of the invention of claim 2 is to provide an unload valve which can omit complicated processing of the piston guide and can shorten the length of the piston guide.

[0006]

The present invention will be described with reference to the drawings corresponding to the embodiments. The unload valve (10) of the first aspect has the following components (a) to (e). (A) a check valve (28) which allows a one-way flow of liquid from the inlet (14) to the outlet (24); (b) the check valve (28) is displaced with the axial displacement of the valve stem (40); )
Unloading valve (36) that controls the connection between the fluid and the spill port (16) (c) The axial position is fixed to the valve stem (40) so that it can be adjusted, and the outlet
When the pressure of (24) becomes high, the piston (4) is displaced in the axial direction together with the unloading valve (36) to open the unloading valve (36).
2) (d) an urging member (74) for urging the piston (42) in the closing direction of the unloading valve element (36) and the preload is adjustable freely; (e) an unloading valve element (36) Piston in the opening direction of the (42)
Stopper to limit the displacement of (76)

[0007] The unload valve (10) according to claim 2 further comprises:
It has the following components (f) to (k). (F) The piston guide (56) into which the piston (42) is slidably inserted. (G) The valve rod (40) penetrates and the unloading valve element (36) side with respect to the piston guide (56). Partitioning member (46) (h) Sealing member (50) fitted from the piston guide (56) side into the penetrating portion of the valve rod (40) in the partitioning member (46) (i) Partitioning members (46) from both sides and Piston guide (56)
(J) A washer (52) for preventing the seal member (50) from coming off from the partition member (46) and being formed on the outer peripheral side of the end of the piston guide (56) on the washer (52) side. An annular space (60) communicating with the outlet (24) via the (66) (k) A cut formed in the washer (52) to allow the annular space (60) and the inner peripheral side of the end of the piston guide (56) to communicate with each other. Missing (54)

[0008]

The unload valve according to claim 1, wherein the outlet (2)
4) When the side is closed, the hydraulic pressure at the outlet (24) increases, the check valve (28) is closed, and the communication between the inlet (14) and the outlet (24) is cut off. As a result, the liquid on the outlet (24) side of the check valve (28) is in a sealed state, and the hydraulic pressure at the outlet (24) is greatly increased. The piston (42) is transmitted the increased hydraulic pressure of the outlet (24) through the communication path (66), displaces against the urging member (74), and comes into contact with the stopper (76). . Valve stem (40) is stopper
The piston (42) is displaced in the axial direction with the displacement of the piston (42) toward (76), whereby the unloading valve element (36) is switched from the load position to the unload position, and the liquid at the inlet (14) is Is discharged to the surplus liquid port (16), and the liquid pressure at the inlet (14) decreases.

On the other hand, when the outlet (24) is open, the hydraulic pressure at the outlet (24) decreases, and the check valve (28) is opened, and the inlet (14) and the outlet (24) are opened. And communicate. Piston (42)
Is transmitted the reduced hydraulic pressure of the outlet (24), and the urging member (7
It is displaced by the biasing force of 4). The valve stem (40) is axially displaced toward the unloading valve element (36) with this displacement of the piston (42), whereby the unloading valve element (36) is moved from the unload position to the load position. The liquid at the inlet (14) is sent to the outlet (24).

In order to adjust the unloading time, that is, the axial displacement (= lift) until the displacement of the unloading valve body (36) is limited by the stopper (76), the valve stem (4) is adjusted.
Change the axial position of the piston (42) in (0). Valve stem
The axial position of the piston (42) in (40) is the stopper (76)
From the load position to the unload position, the amount of displacement until the piston (42) comes into contact with the stopper (76) increases, and the unload valve increases. The lift of the body (36) increases.

According to the second aspect of the present invention, the outlet (2)
The hydraulic pressure of 4) is transmitted to the annular space (60) through the communication path (66), and further from the annular space (60) to the piston guide (56) through the notch (54) of the washer (52). It is transmitted to the inner peripheral side and acts on the end face of the piston (42).

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a vertical sectional view of the unload valve 10. The body 12 has an inlet 14 and a spill port 16 on the side and bottom respectively, and the inlet 14 and the spill port 16 are connected to a pump outlet and a liquid source, respectively. The valve seat 18 is located on the opposite side of the body from the inlet 14.
12 is inserted into the body 12 from the side, and the inlet 14
Connected to 16. The valve body 20 is slidably fitted in the hose connecting member 22 in the axial direction, and the valve seat 18 and the valve body 20 are connected to the check valve 28.
Is configured. The hose connecting member 22 is inserted and screwed into the body 12 following the valve seat 18, presses the valve seat 18 against the step in the body 12, and has an outlet at the end exposed from the body 12. Has 24. The hose connecting member 22 has a hose (not shown) attached to an end on the outlet 24 side, and connects the outlet 24 to a trigger nozzle (not shown) via the hose. The compression coil spring 26 is inserted into the hose connection member 22 on the back side of the valve body 20, and biases the valve body 20 toward the valve seat 18. The through hole 30 is opened at the end face of the valve body 20 on the outlet 24 side, communicates with the outlet 24, extends along the center line of the valve body 20, and the end of the valve body 20 on the valve seat 18 side. And communicates with an annular space 32 on the periphery. When the valve body 20 is separated from the valve seat 18, the inner hole of the valve seat 18 is formed in the annular space 32 and the through hole 30.
To the exit 24 via.

The valve seat 34 has an inlet 14 and a valve seat 18 on the upper side.
The body 12 is fitted upward into the body 12 so as to communicate with the fluid, and communicates with the surplus liquid port 16 on the lower side. The unloading valve element 36 can be freely seated on the valve seat 34, and the valve seat 34 and the unloading valve element
36 constitutes an on-off valve 38. The valve stem 40 is screwed to the unloading valve body 36 at the lower end, extends upward in the body 12, and has a piston 42 screwed to the upper end. piston
42 is capable of changing the axial position of the valve stem 40 in accordance with the change of the screwing position with the valve stem 40, and the lock nut 44 is screwed to the valve stem 40 above the piston 42, and the piston 42
The contact of the valve stem 40 prevents the piston 42 from loosening in the valve stem 40. The seal plate 46 is inserted from above into the step in the body 12 to partition between the unloading valve body 36 and the piston 42. The O-ring 48 is fitted in an annular groove in the peripheral portion of the seal plate 46 to seal the peripheral portion of the seal plate 46. The O-ring 50 is connected to the valve stem 40 of the seal plate 46.
In order to seal the sliding penetrating part, the upper part is inserted into the penetrating part from above.

FIG. 2 is a front view of the washer 52. Washer 52
At the center, it is slidably penetrated by the valve stem 40 and the sealing plate 46
It is applied to the upper surface. The washer 52 has an arc-shaped notch 54 at a position directly opposite to the circumferential direction.

The piston guide 56 is screwed into the body 12 from above, contacts the washer 52 at a thin end portion 58 at the lower end, and presses the seal plate 46 and the washer 52 downward. The annular space 60 is formed on the outer peripheral side of the thin end portion 58 and communicates with the notch 54. The O-ring 62 is fitted in an annular groove on the outer peripheral side of the lower end of the piston guide 56 above the annular space 60, and seals the lower end of the piston guide 56. The piston ring 64 is fitted around the piston 42 and slidably contacts the inner periphery of the piston guide 56.
Seal between 56 inner circumference. The communication passage 66 is a body
It extends obliquely in 12 and connects the annular spaces 32 and 60 to each other.

The pressure adjusting cap 68 is screwed to the upper end of the piston guide 56, and the lock nut 70 is screwed to the piston guide 56 below the pressure adjusting cap 68 so that the pressure adjusting cap 68 is screwed.
To prevent loosening. A cylindrical collar 72 is inserted into the piston guide 56 above the piston 42, and a compression coil spring
74 is contracted between the upper surface of the cylindrical collar 72 and the lower surface of the end surface of the pressure regulating cap 68 to urge the cylindrical collar 72 downward. The annular projecting portion 76 is integrally formed on the inner peripheral side of the piston guide 56 so as to project radially inward above the piston 42, and is displaced upward by contact with the upper surface of the piston 42. Restrict. L is a piston when the unloading valve element 36 is seated on the valve seat 34.
The distance from 42 to the annular overhang portion 76, and therefore, the lift amount of the unloading valve body 36 is shown.

The operation of the embodiment will be described. piston
42 receives the acting force due to the hydraulic pressure on the lower surface side and the urging force of the compression coil spring 74 to face each other, and is displaced in the axial direction according to the relationship between the two. Notch of washer 52 on the underside of piston 42
It communicates with the annular space 32 via the annular space 60 and the communication passage 66, and is equal to the hydraulic pressure of the outlet 24 in a steady state. Further, by adjusting the screwing amount of the pressure adjusting cap 68 to the piston guide 56, the hydraulic pressure on the lower surface side of the piston 42 when the piston 42 starts rising against the urging force of the compression coil spring 74, that is, the outlet 24 Is adjusted.

When the trigger nozzle communicating with the outlet 24 via the hose is closed, the hydraulic pressure at the outlet 24 increases and the valve body
20 is seated on the valve seat 18 and the check valve 28 is closed. Thereby, the communication between the inlet 14 and the outlet 24 is cut off, and the liquid from the pump is prevented from being sent to the outlet 24, and the liquid is sealed on the outlet 24 side of the check valve 28. , The hydraulic pressure at the outlet 24 increases greatly. This increased hydraulic pressure is
Is transmitted to the lower surface side of the piston 42 through the
42 is raised against the urging force of the compression coil spring 74,
It is brought into contact with the annular overhang portion 76. On the other hand, since the unloading valve element 36 of the on-off valve 38 is screwed onto the valve rod 40, it rises integrally with the piston 42, separates from the valve seat 34, and the on-off valve 38 is opened. As a result, the liquid pressure-fed from the pump to the inlet 14 is sent to the surplus liquid port 16 via the on-off valve 38, returned to the liquid source, and the pump is unloaded.

On the other hand, when the trigger nozzle is opened, the seal on the trigger nozzle side is released from the check valve 28, and the hydraulic pressure at the outlet 24 decreases. As a result, the check valve 28 is opened to allow the inlet 14 and the outlet 24 to communicate with each other. The piston 42
The reduced hydraulic pressure at the outlet 24 is transmitted to the compression coil spring 74.
Of the on-off valve 38 by the urging force of
36 is seated on the valve seat 34, and the on-off valve 38 cuts off the communication between the inlet 14 and the spill port 16. As a result, the liquid pressure-fed from the pump is sent to the trigger nozzle held by the operator via the check valve 28 and the outlet 24, and is ejected from the trigger nozzle.

In order to adjust the unload time, that is, the amount of displacement (= lift amount) until the unloading valve body 36 is restricted from rising by the contact of the piston 42 with the annular overhang portion 76, the lock nut 44 is used. Loosen piston 42 to valve stem 40
To change the screwing position of the piston 42 on the valve stem 40. As a result, the axial position of the piston 42 on the valve stem 40 changes. As the axial position of the piston 42 in the valve stem 40 is further away from the annular overhang portion 76, the unloading valve element
When the switch 36 switches from the load position to the unload position, the displacement amount L displaced until the piston 42 comes into contact with the annular overhang portion 76 increases, and the lift amount of the unloading valve body 36 increases.

In the embodiment, the unloading valve element 36 is
The unloading valve body 36 is formed in a ball shape, and the bowl is fixed to the end of the valve stem 40, and the ball-shaped unloading valve body 36 is screwed to the concave side of the bowl. The unloading valve element 36 may not be fixed to the valve rod 40 (see FIG. 2 of Japanese Utility Model Laid-Open No. 1-139179).

[0022]

According to the first aspect of the present invention, the amount of displacement of the piston is adjusted until the piston is brought into contact with the stopper by adjusting the axial position of the valve stem, thereby increasing or decreasing the lift of the unloading valve element. In addition, the unload time of the unload valve can be appropriately adjusted.

According to the second aspect of the present invention, the washer is sandwiched between the piston guide and the partition member to be pressed, and at the same time, the seal member is prevented from coming off the through-hole of the valve stem in the partition member. With a notch, the hydraulic pressure at the outlet is a communication passage,
The power is transmitted to the end face of the piston through the annular space on the outer peripheral side of the end of the piston guide and the notch of the washer. Therefore, since the through hole for communicating the inner and outer circumferences is removed from the piston guide, the processing of the piston guide is simplified, and the length of the piston guide can be reduced.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of an unload valve.

FIG. 2 is a front view of a washer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Unload valve 14 Inlet 16 Surplus liquid port 24 Outlet 28 Check valve 36 Unloading valve element 40 Valve stem 42 Piston 46 Seal plate (Partition member) 50 O-ring (Seal member) 52 Washer 54 Notch 56 Piston guide 60 Annular space 66 Communication path 74 Compression coil spring (biasing member) 76 Annular extension (stopper)

Claims (2)

(57) [Scope of request for utility model registration] A check valve (28) for allowing a one-way flow of liquid from an inlet (14) to an outlet (24); An unloading valve element (36) for controlling the connection between (14) and the surplus liquid port (16), and the axial position is fixed to the valve rod (40) so as to be adjustable, and the outlet (24) is at a high pressure. Then, the piston (42) which is displaced in the axial direction together with the unloading valve element (36) to open the unloading valve element (36), and the piston in the closing direction of the unloading valve element (36) An urging member (74) for urging the preload (42) and adjusting the preload, and the piston (42) in the opening direction of the unloading valve element (36).
An unload valve having a stopper (76) for limiting displacement of the unload valve. 2. A piston guide (56) into which the piston (42) is slidably fitted, and the unloading valve body penetrated by the valve rod (40) and the piston guide (56). (3
6) A partition member (46) for partitioning the side, and the piston guide (5) is provided at a portion of the partition member (46) that penetrates the valve stem (40).
6) The sealing member (50) fitted from the side, and the separation member (46) and the piston guide (56) from both sides are pressed by the sealing member (50) from the partition member (46). A washer (52) for blocking, and an annular space (60) formed on the outer periphery of the end of the piston guide (56) on the washer (52) side and communicating with the outlet (24) through a communication passage (66). And the washer (52)
The annular space (60) and the piston guide (56)
The unload valve according to claim 1, further comprising a notch (54) for communicating the inner peripheral side of the end portion with each other.