CN2343438Y

CN2343438Y - Liquid controlled unloader with pressure limiting function

Info

Publication number: CN2343438Y
Application number: CN 98219396
Authority: CN
Inventors: 季志刚
Original assignee: SUZHOU AGRICULTURAL CHEMICAL MACHINERY FACTORY
Current assignee: SUZHOU AGRICULTURAL CHEMICAL MACHINERY FACTORY
Priority date: 1998-08-21
Filing date: 1998-08-21
Publication date: 1999-10-13
Anticipated expiration: 2008-08-21

Abstract

The utility model relates to a liquid controlled unloading valve with a pressure limiting function for a mobile cleaner and a power sprayer. The utility model is composed of a valve body, a water outlet valve, a water back valve, a sliding valve, etc. The utility model is characterized in that the lower end of a regulating screw thread of the sliding valve is provided with a screw thread recess. After screwed to the bottom, the regulating cap can not be screwed, and a limit of maximum pressure for a system is reached. The utility model can prevent machines and tools from being damaged caused by incorrect use. A safety valve does not need to be additionally arranged, and requirements of a safety standard can be reached. The utility model has the advantages of simple structure, low cost, and multiple functions.

Description

A kind of hydraulic unloading valve of limited compression functions

The utility model relates to the safety valve in a kind of mechanical engineering, is specially adapted to mobile cleanser and engine-driven atomiser.

At present, the engine-driven atomiser of China also all uses traditional manual discharging type pressure regulator valve.What the automatic deloading valve that uses on washing machine was seen in document has CN87212912, a CN87213516 etc.These several valves all have pressure regulation and unloading function, and particularly back two kinds of patent valves all are hydraulic control automatic deloading, have played sizable effect working life for saving energy and reduce the cost of washing machine reaches to improve.Though the deficiency of this valve is the problem that has solved hydraulic control automatic deloading, but because it has considered stepless voltage regulation, thereby get the adjusting screw thread design on the guiding valve very long, this just makes heightens pressure and has not had restriction, so all do not have the pressure limiting function, after surpassing the regulation working pressure even exceeding maximum pressure, can also continue up pressure regulation; Particularly after the flow of pump and injection flow equate, screw the situation that the maximum pressure that the constant and actual pressure unloading of pressure gauge indicated value but allows well beyond facility can appear in pressure adjusting roller again.Also have some not users of by specification operation, under off-mode, screw pressure adjusting roller driftlessness, the maximum pressure that pressure unloading is allowed well beyond facility, pressure gauge is broken in the meeting that its consequence is light, serious meeting damages the moving element of pump, thereby causes the complete machine paralysis.

The purpose of this utility model is to overcome the deficiency of above-mentioned valve and a kind of hydraulic control automatic deloading valve with pressure limiting function is provided.

The technical solution of the utility model is: this hydraulic unloading valve, form by valve body, outlet valve, back-water valve (BWV) and guiding valve etc., outlet valve and back-water valve (BWV) are separated into water-inlet cavity, water chamber and backwater cavity with valve body, the piston place of guiding valve is communicated with water chamber, guiding valve is provided with regulates cap and spring, and its main feature is that the adjusting screw thread lower end of guiding valve is provided with Gewindefreistiche.Like this, just make to regulate and again can not revolve after cap is screwed into the end, thereby reach the control of the maximum pretightening force of spring, also just reached the restriction of system's maximum pressure.

Consider the foozle of part, the foozle of spring size and stiffness particularly, the utility model is provided with the adjusting pad regulating between cap and the spring, thereby makes the maximum pretightening force of spring obtain controlling comparatively accurately.

Because pressure-regulating device is locked, the facility that the utility model can be avoided causing because of incorrect use damage, and do not need to be provided with separately safety valve and can reach the safety standard requirement; It is simple in structure, cost is low, and has the multi-functional characteristics of a valve.

Describe the technical solution of the utility model in detail below in conjunction with accompanying drawing (embodiment).

Fig. 1 is a structural representation of the present utility model.

Fig. 2,3,4 is respectively relevant parts guiding valve, the big nut of valve, the structural representation of latch bracket.

The utility model mainly is made up of valve body 9, outlet valve 12, water output connector 13, backwater valve seat 10, back-water valve (BWV) 11 and pressure regulation pressure limiting combined mechanism etc., and outlet valve 12 separates into water-inlet cavity A, water chamber B and backwater cavity C with back-water valve (BWV) 11 with integral body.At first close back-water valve (BWV) 11 after flowing to the A chamber by the liquid of pump output, open outlet valve 12 and enter the B chamber and be sent to spray gun and penetrate; Simultaneously pressure is also delivered on the piston that B1 place acts on guiding valve 2, and promotion guiding valve 2 moves downward, and overcomes the power of spring force and back-water valve (BWV) 11 and backs down back-water valve (BWV), and liquid is flow to into backwater cavity C; And opening of C chamber can make system pressure descend, and the power that acts on the guiding valve 2 also reduces thereupon, and guiding valve moves upward again under the effect of spring 6 power, and back-water valve (BWV) 11 just cuts out, and system pressure rises again, and guiding valve backs down back-water valve (BWV) again downwards.When reaching balance, an osculum only left by back-water valve (BWV), has only part liquid stream to overflow from back-water valve (BWV), and system is in overflow situation.The height of system pressure can be regulated cap 3 by turn and changed the size of spring 6 power and realize this moment.When the liquid stream that is sent to spray gun when the B chamber is closed by spray gun, the liquid stream in A chamber just can not enter the B chamber, outlet valve 12 is just closed, this moment, the pressure in B chamber reduced with regard to the reduction because of the A cavity pressure no longer, the power that acts on guiding valve 2 pistons is constant with regard to keeping backing down back-water valve (BWV) 11, liquid stream just all enters backwater cavity C, and the flow stream pressure of pump output approaches zero with regard to drop to always, and system is in unloading condition.When spray gun was opened again, the B cavity pressure descended rapidly, and guiding valve 2 also rises rapidly under the effect of spring 6, and back-water valve (BWV) 11 cuts out, and liquid stream is opened outlet valve 12 again and entered the B chamber and be sent to the spray gun ejaculation, and the pressure regulation overflow situation is got back to by system.But more than be exactly the hydraulic principle that the hydraulic unloading valve can make washing machine or atomizing sprayer high pressurized overflow, automatic deloading when the pass rifle is not worked when shooting is sprayed.For solving the pressure limiting problem, the utility model adopts the maximum pretightening force of control spring to reach the pressure limiting purpose, it is exactly Gewindefreistiche 16 of adjusting screw thread processing with guiding valve 2, make to regulate and again can not revolve after cap is screwed into the end, thereby reach the control of the maximum pretightening force of spring, also just reached the restriction of system's maximum pressure.As shown in Figure 1, in fact pressure regulation pressure limiting combined mechanism is made up of nut 1, guiding valve 2, adjusting cap 3, adjusting pad 4, latch bracket 5, spring 6, elastic cylindrical pin 7 and big nut 8 etc.The control size L of guiding valve 2 deducts the size L1 of big nut 8, and the control size L2 that deducts latch bracket 5 again is (referring to Fig. 2～Fig. 4), formed the minimal compression height of spring.The effect of regulating pad is for the maximum pressure of control system more accurately, and is lower than the requirements of maximum pressure, still can regulate nut and reach stepless voltage regulation with unscrewing.In this embodiment, consider again to make a call to a hole, and be locked, mustn't the user at will dismantle, to get rid of artificial error with iron wire 14 and lead sealing 15 at nut 1 and guiding valve 2 assembling backs.

Claims

1. the hydraulic unloading valve of a limited compression functions, form by valve body (9), outlet valve (12), back-water valve (BWV) (11) and guiding valve (2) etc., outlet valve (12) and back-water valve (BWV) (11) are separated into water-inlet cavity (A), water chamber (B) and backwater cavity (C) with valve body, the piston place of guiding valve (2) is communicated with water chamber (B), guiding valve (2) is provided with regulates cap (3) and spring (6), and it is characterized in that: the adjusting screw thread lower end of guiding valve (2) is provided with Gewindefreistiche (16).

2. hydraulic unloading valve according to claim 1 is characterized in that: be provided with between adjusting cap and spring and regulate pad (4).