CN2122291U

CN2122291U - Pressure release valve

Info

Publication number: CN2122291U
Application number: CN 91229230
Authority: CN
Inventors: 今田义夫
Original assignee: NIIAWA INDUSTRIAL Co Ltd
Current assignee: NIIAWA INDUSTRIAL Co Ltd
Priority date: 1991-09-11
Filing date: 1991-11-18
Publication date: 1992-11-18
Also published as: JPH0571651A

Abstract

The utility model discloses a pressure reducing device, comprising a cylinder body 1, a valve rod 2 and a ring piston 7 and other components. The time difference in the occurrence period of pressure reducing function after the rated operation pressure is obtained can be provided. The valve rod 5 is extruded by a spring 4 with strong elasticity and the ring piston 7 is extruded by a spring 6 with weak elasticity. The valve rod 5 can freely slide in the ring piston 7. The valve rod 5 is provided with a combination surface 8a. The ring piston 7 rapidly upward moves before contacting the combination surface 8a and further upward moves in the deceleration state after contacting the combination surface. A discharging hole completely opens on the upper limit position of the ring piston 7.

Description

Pressure release valve

The utility model relates to a kind of relief valve unit, and it is used for reducing pressure automatically distribution system, a plurality of positions supply of lubricant that this system lubricates to needs by distributor.

As everyone knows, the automatic decompression distribution system in past, the distribution system of being announced as " special public clear 59-22111 communique " is when by distributor during toward the many places supply of lubricant, at first, by pump oil is pressed in the distributor from the person in charge, make its oil storage, when pump stops to drive, make decompression in the person in charge by relief valve unit, thus, the oil that is stored up is supplied with each lubricating point.The characteristics of this reduction valve are to reach decompression in the following cases, that is, pump is out of service, fluid does not flow, fluid resistance reduces; Or tube fluid becomes decompression state by pressurized state.

Following bad working condition can appear in this in the past relief valve unit, promptly, along with the increase of being responsible for length, different at fluid upper reaches end with the pressure loss that dirty end is caused by the pipe internal resistance, therefore, when the mounting point of relief valve unit was incorrect, even the lubricating point fuel feeding of upper reaches end is good, the lubricating point fuel feeding situation of dirty end can be not good yet.The viscosity variation that causes along with the ambient temperature difference also causes same bad condition.For this situation of unlikely generation, will prolong the driving time of pump, and so, cause following problems again, that is, unnecessary load is added to the pump motor and installs everywhere, thereby will shorten the working life of device.

The purpose of this utility model is to overcome above-mentioned shortcoming, in certain time lag before promptly carrying out according to decompression, can give the regular hour delay.After working pressure reached before decompression took place, install self and detect, then carry out decompression.

The utility model includes cylindrical shell, valve rod and annular piston, and cylindrical shell has a clack box that is connected with Working-fluid intaking; Valve rod is contained in the valve rod extrusion spring effect in the clack box, the switching of control fluid input; Annular piston is inlaid in the clack box, can be free to slide, and it is subjected to the annular piston extrusion spring effect in the clack box on the one hand, guarantees again that on the other hand valve rod is free to slide.The elastic strength of above-mentioned annular piston extrusion spring is littler than valve rod extrusion spring; Form on the above-mentioned valve rod one can with the contacted junction plane in annular piston top; Above-mentioned cylindrical shell upper punch is provided with the access hole that the fluid letting out the hole and can make the annular piston back side is come in and gone out, when the upper end of above-mentioned annular piston near cylinder inboard wall and even with upper limit position that cylindrical shell contacts the time, letting out the hole is full-gear.

Surpassing under the given working pressure situation of this device, when fluid enters clack box from inflow entrance, because the extrusion spring intensity of the extrusion spring strength ratio valve rod of annular piston is little, thereby, annular piston rises quickly than valve rod, makes annular piston contact (fast rise stage in early stage) with the junction plane of valve rod.After both contacts, owing to must compress two extrusion springs of valve rod and annular piston, therefore, annular piston further rises under deceleration regime with valve rod, soon, the upper-end surface of annular piston is just approaching and even directly contact cylinder inboard wall (later stage low speed ascent stage), under this state, let out the hole and open, present the overflow decompression.That is to say that after pipeline surpassed given working pressure, this device self detected, and then, according to certain time difference of fast rise stage in early stage and later stage low speed ascent stage, just can carry out the decompression of pipeline.

Details are as follows to the utility model below in conjunction with preferred embodiment and accompanying drawing, wherein:

Fig. 1 is the state profile before the relief valve unit work of the present utility model;

Fig. 2 is the sectional drawing of Fig. 1 decompressor work initial state;

Fig. 3 is the annular piston sectional drawing of propradation further of relief valve unit among Fig. 2;

Fig. 4 is the section that its decompression of relief valve unit among Fig. 3 begins the state that takes place;

Fig. 5 is the valve rod reset mode.

Fig. 1 is an embodiment of the present utility model, and among the figure, cylindrical shell 1 is made of top end cap 1a and bottom cylindrical shell 1b, and both are spun on together by screw thread, and the internal cavities of cylindrical shell 1 constitutes clack box 3, and clack box 3 is communicated with the inflow entrance 2 of working fluid.Top end cap 1a upper punch has fluid access hole 10, and screw thread 11 is installed in addition in addition, relief valve unit can be fixed on a plurality of appropriate positions by screw thread is installed.The side of bottom cylindrical shell 16 dashes and lets out hole 9, and there is valve seat 12 end of fluid input 2.

Be provided with valve rod 5 in the clack box 3, it is pushed by the valve rod extrusion spring 4 in the clack box; There is the steel ball spool 13 that can float in the front axle termination portion of valve rod 5, and it is pressed in and just can makes above-mentioned fluid input 2 be in closed condition on the valve seat 12.Steel ball 13 also can be general spool.The rear portion axle head setting-in of valve rod 5 flange spring seat 8, is the spring seat of above-mentioned valve rod extrusion spring 4 above the flange, be below the flange can with annular piston 7 contacted junction plane 8a.Also available ring, the circle (not shown) that is fixed on the valve rod 5 of flange spring seat 8 replaces.

Also be provided with annular piston 7 in the clack box 3, it is the cylindrical form that the end is arranged, and can be inlaid in the clack box with being free to slide, and the annular piston that is installed in the clack box 3 pushes with extrusion spring 6.The bottom centre position of annular piston 7 is equipped with flanged sleeve 14, and it guarantees that above-mentioned valve rod 5 is free to slide.The elastic strength of annular piston extrusion spring 6 is littler than valve rod extrusion spring 4, and its reason hereinafter describes in detail.

When the main line of the automatic decompression of this device connection distribution system and fluid inflow entrance 2, its working condition is as follows:

Usually, the pressure that is loaded on after the abundant oil storage of distributing valve of main line is roughly 8-14kg/cm ², therefore, with the rated working pressure of this value as this device.Out of service when pump (not shown), the hydrodynamic pressure at fluid input 2 places is when rated working pressure is following, and as shown in Figure 1, because the acting in conjunction of valve rod extrusion spring 4 and annular piston extrusion spring 6, steel ball 13 is pushed down valve seat 12, and fluid input 2 is closed.And enter the mouth the hydrodynamic pressure at 2 places when surpassing rated working pressure when the pump driving fluid, and as shown in Figure 2, steel ball 13 is lifted off a seat and 12 is risen, and fluid enters clack box 3.So, as indicated above, because the elastic strength of the extrusion spring 6 of annular piston 7 is littler than the elastic strength of the extrusion spring 4 of valve rod 5, therefore, annular piston 7 fast rise, on the other hand, the fluid at the annular piston back side drains into the outside from access hole 10, soon just reach the state as Fig. 3, that is, the end top that is loaded on the sleeve 14 of annular piston 7 bottom centre positions contacts with following (being junction plane 8a) of the flange spring seat 8 of valve rod 5.

Annular piston 7 rises owing to compressing two

extrusion springs

4,6 simultaneously with after the junction plane 8a of valve rod 5 contacts, and therefore, the rate of climb of annular piston 7 slowed down than in the past.Soon just become the state of Fig. 4, that is, the top of annular piston 7 near so that directly contact the inwall of cylindrical shell top end cap, when reaching this upper limit position, let out hole 9 standard-sized sheets.Thereby the feed fluid that fluid input 2 is come in is discharged through letting out hole 9, and the decompression of main pipe system promptly takes place thus.Pressure under the decompression state is 0.5-2.5kg/cm ²About.

The state of Fig. 4 can be maintained to pump out of service before.Since the effect of the time relay (not shown), when pump is out of service, as shown in Figure 5, since the resilient beam of valve rod extrusion spring 4, the position recovering of the at first past fluid input 2 of valve rod 5.After a while, annular piston 7 resets toward original position.Though valve rod 5 had been closed valve seat 12 when annular piston 7 resetted, because the fluid in the clack box flows into annular piston 7 behind via the narrow and small slit between annular piston 7 peripheries and clack box 3 inwalls, therefore, annular piston 7 slowly presses down, and finally gets back to the state of Fig. 1.

From following explanation as seen, this structure of the present utility model has following characteristics, that is, can detect voluntarily after reaching rated operating pressure; Start to the time that depressurization takes place at annular piston, can obtain desired time delay; In addition, aspect increasing or shortening its time delay, be easy to regulate. Therefore, even in the following cases, also can in above-mentioned time delay, make the pressure of the terminal oil site of pipeline position reach set-point. This situation, that is, trunk line is longer, and relief valve unit fluid intake place has reached rated operating pressure, and the oil site position of pipeline end does not also reach enough pressure because of the impact of pipe internal resistance. These characteristics of this device have superiority aspect the choosing of its installation site.

Claims

1, a kind of relief valve unit is characterized by: it is made up of cylindrical shell 1, valve rod 5 and annular piston 7, and cylindrical shell 1 has a clack box that is communicated with Working-fluid intaking 3; Valve rod 5 is contained in valve rod extrusion spring 4 effects in this clack box 3, control the switching of above-mentioned fluid input 2, annular piston is inlaid in the clack box 3, can be free to slide, it is subjected to being contained in annular piston extrusion spring 6 effects in the clack box 3 on the one hand, guarantee again that on the other hand valve rod 5 is free to slide, the elastic strength of above-mentioned annular piston extrusion spring 6 is littler than valve rod extrusion spring 4, a junction plane 8a that can collide and connect with annular piston 7 is arranged on the above-mentioned valve rod 5, cylindrical shell 1 upper punch is provided with the access hole 10 of the fluid discrepancy of letting out hole (overflow hole) 9 and can make the annular piston back side, when the upper end of annular piston 7 in upper limit position that cylinder inboard wall contacts the time, let out hole 9 and be in full-gear.

2, relief valve unit as claimed in claim 1.It is characterized by: above-mentioned junction plane 8a is below flange spring seat 8, and flange spring seat 8 is inlaid in the rear portion axle head of valve rod 5.