CN1156211A

CN1156211A - Hydraulic impact device for stepless independently regulating impact energy and impact frequency

Info

Publication number: CN1156211A
Application number: CN 96118034
Authority: CN
Inventors: 杨襄璧; 晏从高; 赵宏强; 胡均平; 罗春雷
Original assignee: Central South University
Current assignee: Central South University
Priority date: 1996-02-02
Filing date: 1996-02-02
Publication date: 1997-08-06
Anticipated expiration: 2016-02-02
Also published as: CN1049471C

Abstract

The present invention discloses a kind of hydraulic impact device for stepless independently regulating impact energy and impact frequency. It adopts the HD pump to supply oil, the impact fequency can be stepless regulated by changing the flow rate of HD pump. The out put of HD pump connects via the oil way to the normally high pressure chamber of the oil distributing valve, back stroke push valve chamber and cone valve. The oil way connects through the control of cone valve to the stroke push valve chamber. The opening of the cone valve controls the pressure to be continuously adjustable and makes the impact energy be capable of adjusting independently and stepless. There are stroke limiting stairs on piston and corresponding stroke limiting cavities in the cylinder. Said invention features small leakage, high efficient, low frequency lower limit, capable of fully using the installed capacity and heightening the impact energy.

Description

The hydraulic impact device of stepless independent regulation impact energy and frequency of impact

The present invention relates to a kind of by operating cylinder and oil distributing valve are formed, dynamic hydraulic combined drives impact shock machinery.

The hydraulic impact device that uses at present domestic and international hydraulic gate, the hydraulic lithotriptor, some can regulate impact energy and frequency of impact.As the disclosed a kind of impactor of Chinese utility application CN85202026 (on June 11st, 1986), be that a plurality of valve openings that push away are set on oil cylinder, adjust adjusting plug the valve opening that pushes away of diverse location is communicated with oil distributing valve, can obtain several impact energys and frequency of impact.The MKB1300 hydraulic impactor made of Mitsubishi business Co., Ltd. for another example, in the normal high pressure chest of oil cylinder, radially have two adjustment holes, communicate with high-pressure oil passage respectively, the junction of two oil circuits has a control valve to control the break-make of two oil circuits, thereby the change piston stroke obtains two kinds of frequency of impacts and the corresponding two kinds of impact energys of 15Hz or 7.5Hz.Above-mentioned hydraulic impactor all can only be accomplished grade adjusting that has of impact energy and frequency of impact, be difficult to adapt to the needs of various operating modes, and the impact energy of impactor and percussion power be to change synchronously in adjustment process, when impact energy increases, percussion power also increases, and this just requires to increase installed capacity.Like this, under low impact energy condition, installed capacity is not in full use, and the un-reasonable phenomenon that little percussion power is joined in big installed capacity occurs.In addition, SU1084485A of the former Soviet Union disclosed " a kind of ground lithotriptor " and Chinese patent application CN88105670 (on October 7th, 1992) disclosed " stepless frequency-adjusting and cone valve controlled hydraulic shocking device ", its oil cylinder adopts the impact piston of separate unit shoulder, and make frequency of impact controlled the return interval that is prolonged impact piston by throttle valve control oil extraction speed.Its weak point is to regulate frequency of impact, can not regulate impact energy, and the throttle valve adjustment pressure loss is big, and fluid generates heat easily, and has the high-low pressure oil of short time directly to communicate, and has leakage loss, and efficient is low.Above-mentioned all percussion mechanisms also exist the frequency of impact can not too low common drawback, promptly install capacity one regularly, and impact energy can not be too big.

For overcoming the deficiencies in the prior art, the objective of the invention is to design a kind of can stepless independent regulation impact energy and frequency of impact, oil liquid leakage is few, lower-frequency limit is low, efficient is high hydraulic impact device.

Hydraulic impact device of the present invention adopts HD pump variable flow control mode, and high pressure fuel source P is provided by the HD variable delivery pump, change the flow of HD pump, can obtain different frequency of impacts, because of the flow of HD pump stepless adjustable, thereby make frequency of impact of the present invention independent stepless adjustable.The output of HD pump pushes away valve pocket and cone valve through normal high pressure chest, the backhaul that oil circuit connects oil distributing valve respectively, the oil sources that connects cone valve is controlled its break-make through cone valve, the stroke of receiving oil distributing valve again pushes away valve pocket, the unlatching controlled pressure of cone valve is adjustable continuously, but thereby make also step-less adjustment of impact energy of the present invention, the present invention adopts traditional travel feedback mode, but carries out pressure feedback control by cone valve, and stroke signal is controlled by the cone valve opening pressure.The impact piston that is assemblied in the cylinder body has two shoulders, form four cavity volumes in the cylinder body, be followed successively by from front to back: the normal high pressure chest that has oilhole, can be communicated with the normal low pressure chamber that backhaul feedback signal hole communicates with oil return T, the transformation chamber at rear portion and airtight nitrogen chamber, the anterior normal high pressure chest of oil cylinder communicates with high pressure fuel source through oil circuit and oil distributing valve, and is provided with high pressure accumulator.The impact piston rear end is provided with the stroke limit step, piston/cylinder is provided with corresponding with it stroke limit chamber, before the stroke limit step enters the stroke limit chamber, stroke limit chamber and transformation chamber interconnect, the transformation chamber forms closed chamber, the degree of leaveing position and buffering effect after the stroke limit step enters the stroke limit chamber.

Hydraulic impact device of the present invention, impact energy and frequency of impact can independent step-less adjustment be controlled, and installed capacity one timing is no matter the height requirement of impact energy and frequency of impact all can make full use of installed capacity.

Fig. 1 is the structural representation of backhaul initial state of the present invention;

Fig. 2 is the structural representation of stroke initial state of the present invention.

Now details are as follows to concrete condition of the present invention in conjunction with the accompanying drawings:

The impact piston 1 that is assemblied in the cylinder body 14 has shoulder 4 and shoulder 7 and a stroke limit step 9, form four cavity volumes in the cylinder body, promptly have the normal high pressure chest 2 of oilhole 20, the normal low pressure chamber 6 that can be communicated with backhaul feedback signal hole 19 and hole 18, with the transformation chamber 10 that the oilhole 17 of oil pocket 12 communicates, airtight nitrogen chamber 15.Oil cylinder is provided with the stroke limit chamber 11 corresponding with piston stroke limited step 9, before stroke limit step 9 enters stroke limit chamber 11, chamber 11, chamber 10 are communicated with oil pocket 12, after stroke limit step 9 enters cylinder body stroke limit chamber 11, chamber 10 becomes closed chamber, the degree of leaveing position and returning buffering effect.The anterior normal high pressure chest 2 of oil cylinder communicates with high pressure fuel source P through the normal high pressure chest 37 of oilhole 20 by oil circuit 24 and oil distributing valve, and the oil sources passage is provided with high pressure accumulator 38.Oilhole 19 pushes away valve pocket 41 by the oil circuit 22 and the stroke of oil distributing valve and is communicated with, and oilhole 18 is communicated with oil return T by the normal low pressure chamber 31 of oil circuit 26 and oil distributing valve, and is provided with low pressure accumulator 32 on drainback passage.Stroke is finally the time, and oilhole 19 is crossed in shoulder 4 right sides 5, and oil pocket 6 is communicated with oilhole 19 and oilhole 18.Oil cylinder rear portion oil pocket 12 is communicated with the transformation chamber 34 of oil distributing valve by oil circuit 25 through oilhole 17.If the area of the useful effect face 3 of piston 1, acting surface 8, acting surface 13 is respectively f1, f2, f3 should meet relational expression f1＜f2+f3.Piston also has a nitrogen acting surface 16.

Valve body 27 has a plurality of cavity volumes with the oil distributing valve that spool 28 is formed.Stroke pushes away valve pocket 41 and communicates with pressure control cone valve 21 through oil circuit 23, control the break-make of itself and high pressure fuel source P by cone valve, the high pressure fuel source P of HD pump output leads to cone valve through oil circuit 40, and cone valve can be the cone valve of any standard, also can be special controllable pressure sequence valve; The opening pressure of pressure control cone valve 21 determines that by control oil pressure Px Px is big, and I is regulated continuously by reducing valve.The left side sealing shoulder 36 of spool 28, the right sealing shoulder 33, alternately control the break-make in normal high pressure chest 37 of oil distributing valve and transformation chamber 34 and normal low pressure chamber 31 of oil distributing valve and transformation chamber 34 respectively, when chamber 37 is communicated with chamber 34, chamber 31 and chamber 34 blocking-up, when blocked with chamber 34 in chamber 37, chamber 31 was communicated with chamber 34, and the area of the useful effect face of spool 39 is greater than the area of acting surface 30.Backhaul pushes away valve pocket 29 and communicates with high pressure fuel source P through oil circuit 35, and the normal high pressure chest 37 of oil distributing valve also directly communicates with high pressure fuel source by oilhole.

Operating principle of the present invention is as follows: one, backstroke (original position of piston and spool as shown in Figure 1)

Spool 28 pushes away under the effect of high pressure compression face 30 power of valve pocket 29 (this moment stroke push away valve pocket 41 be low pressure) and is in position, a left side in backhaul, hydraulic oil is through the normal high pressure chest 37 of oil distributing valve, and oil circuit 24 enters normal high pressure chest 2 by oilhole 20, piston begins backhaul, the oil in transformation chamber 10 is through oil pocket 11,12, oilhole 17, oil circuit 25, oil distributing valve transformation chamber 34, the normal low pressure chamber 31 of oil distributing valve be to the T oil return, simultaneously piston compressed nitrogen air chamber.After piston stroke limited step 9 enters stroke limit chamber 11,10 sealings of transformation chamber, not oil return, piston stops, transformation chamber 10 sealing bufferings, backhaul so far finishes.High pressure accumulator is oil-filled, system pressure raises, when system pressure is elevated to the opening pressure of pressure control cone valve 21, cone valve 21 is opened, hydraulic oil enters stroke through

oil circuit

40,23 and pushes away valve pocket 41, and spool 28 moves to right at the power difference effect bottom spool of compression face 39 with normal compression face 30, make spool be in right position, percussion mechanism changes stroke over to.Two, impact stroke (original position of piston and spool as shown in Figure 2)

Piston back cavity 12 is through oilhole 17, oil circuit 25, and oil distributing valve transformation chamber 34, normal high pressure chest 37 is connected with high pressure fuel source P, and piston rear portion active area f2+f3 is greater than anterior active area f1, and under effect of power difference and nitrogen expansion effect, piston carries out stroke to left movement.When returned signal hole 19 is crossed on piston land 4 right sides 5, stroke pushes away valve pocket 41 and is connected with oil return T through oil circuit 22, oilhole 19, chamber 6, hole 18, oil circuit 26, the normal low pressure chamber 31 of oil distributing valve, spool 28 moves to left under normal high-pressure side 30 effects, when piston impact pick rod 42 and when beginning to rebound, spool 28 has commutated and has finished and be in left side position, so far finishes impact stroke.System is in state shown in the accompanying drawing 1, restarts next circulation drawback movement.

Can find out that by above-mentioned operating principle pressure control cone valve 21 control system pressure P are after other parameters of device are fixing, regulate control oil pressure Px, the cone valve controlled pressure can steplessly change, thereby the impact energy of percussion mechanism also can steplessly change, the pressure height, impact energy is big; Pressure is low, and impact energy is little.By the flow of stepless control HD pump feed system, frequency of impact that can stepless control percussion mechanism, frequency of impact height when flow is big, flow hour frequency of impact is low, can realize the step-less adjustment of percussion mechanism impact energy and frequency of impact.

Claims

1. the hydraulic impact device of stepless independent regulation impact energy and frequency of impact comprises oil cylinder, piston, and oil distributing valve, accumulator, nitrogen chamber is characterized in that: the present invention

(1) is provided with the HD variable delivery pump of controlling this percussion mechanism flow;

(2) but be provided with and connect HD variable delivery pump output and lead to the cone valve that the oil distributing valve stroke pushes away the stepless change opening pressure of valve pocket.

2. hydraulic impact device according to claim 1 is characterized in that: described cone valve can be the cone valve of any standard, also can be special controllable pressure sequence valve.

3. hydraulic impact device according to claim 1 is characterized in that: the piston of oil cylinder has shoulder 4, shoulder 7 and step 9, and oil cylinder also is provided with the stroke limit chamber 11 that can with step 9 form sealing corresponding with step 9.

4. according to claim 1 or 2 or 3 described hydraulic impact devices, it is characterized in that: the width of shoulder 4 is less than oilhole 19 distance to cylinder ports, and stroke can be crossed oilhole 19 in shoulder 4 right sides 5 finally the time.