阅读说明：本技术 一种液压机压力控制系统及控制方法 (Hydraulic machine pressure control system and control method ) 是由 陈之现 马敬磊 张海英 于 2020-06-16 设计创作，主要内容包括：本发明公开了一种液压机压力控制系统及控制方法,所述液压机压力控制系统包括螺堵,所述螺堵内设有安装孔,所述安装孔的下端固定安装有阀套,所述阀套内设有第一滑孔和第二滑孔,所述第一滑孔的下端安装下螺套,所述下螺套的下端为P口,所述阀套的侧面设有T口,所述第一滑孔内滑动连接有阀芯,所述阀芯上设有塞体；所述安装孔的上端固定安装有上螺套,所述上螺套的上端开口处固定安装有导磁管,所述导磁管内滑动连接有衔铁,所述衔铁的下端安装有滑套,所述导磁管内设有用第一弹簧,所述导磁管的外侧设有线圈；所述安装孔内形成控制腔,所述控制腔内设有第二弹簧；该液压机压力控制系统不仅结构简单,而且可以实现安全阀和泄压阀的功能。(The invention discloses a pressure control system and a control method of a hydraulic machine, wherein the pressure control system of the hydraulic machine comprises a plug, a mounting hole is arranged in the plug, a valve sleeve is fixedly mounted at the lower end of the mounting hole, a first sliding hole and a second sliding hole are arranged in the valve sleeve, a lower screw sleeve is mounted at the lower end of the first sliding hole, the lower end of the lower screw sleeve is a P port, a T port is arranged on the side surface of the valve sleeve, a valve core is connected in the first sliding hole in a sliding manner, and a plug body is arranged on the valve core; an upper threaded sleeve is fixedly mounted at the upper end of the mounting hole, a magnetic conduction pipe is fixedly mounted at an opening at the upper end of the upper threaded sleeve, an armature is connected in the magnetic conduction pipe in a sliding manner, a sliding sleeve is mounted at the lower end of the armature, a first spring is arranged in the magnetic conduction pipe, and a coil is arranged on the outer side of the magnetic conduction pipe; a control cavity is formed in the mounting hole, and a second spring is arranged in the control cavity; the hydraulic press pressure control system is simple in structure and can realize the functions of a safety valve and a pressure release valve.)

1. A pressure control system of a hydraulic machine is characterized by comprising a plug, wherein a vertically-penetrating mounting hole is formed in the plug, a valve sleeve is fixedly mounted at the lower end of the mounting hole, a first sliding hole and a second sliding hole are sequentially formed in the valve sleeve from bottom to top along the axial direction of the mounting hole, the upper end of the second sliding hole is communicated with the mounting hole, the first sliding hole is communicated with the second sliding hole and is coaxially arranged, a lower screw sleeve is fixedly mounted at the opening at the lower end of the first sliding hole, the lower end of the lower screw sleeve is a P port, a T port communicated with the first sliding hole is formed in the side surface of the valve sleeve, a valve core used for controlling the connection and disconnection of the P port and the T port is connected in the first sliding hole in a sliding mode, a plug body extending into the second sliding hole is arranged on the valve core, and the diameter of the valve core is larger than that of the plug body; an upper threaded sleeve is fixedly mounted at the upper end of the mounting hole, a magnetic conduction pipe is fixedly mounted at an opening at the upper end of the upper threaded sleeve, a plug is fixedly mounted at the upper end of the magnetic conduction pipe, an armature is connected in the magnetic conduction pipe in a sliding manner, a sliding sleeve extending into the mounting hole is fixedly mounted at the lower end of the armature, a first spring for forcing the armature to move downwards is arranged between the armature and the plug in the magnetic conduction pipe, and a coil is arranged on the outer side of the magnetic conduction pipe; a control cavity is formed between the sliding sleeve and the valve sleeve in the mounting hole, and a second spring for forcing the plug body to move downwards is arranged in the control cavity; when the coil is electrified, the armature moves upwards and compresses the second spring, and the control cavity is communicated with the T port; when the coil is powered off, the armature moves downwards under the action of the second spring, and the control cavity is communicated with the port P.

2. The hydraulic machine pressure control system according to claim 1, characterized in that the outer circumferential side of the sliding sleeve is provided with a first ring groove, and the side wall of the sliding sleeve is provided with a first through hole for communicating the control cavity and the first ring groove; a second through hole for communicating the mounting hole with the T port is formed in the plug; a communicating cavity communicated with the port P is formed at the upper end of the valve sleeve in the plug, and a third through hole used for communicating the communicating cavity with the mounting hole is formed in the plug; when the coil is electrified, the first ring groove is communicated with the second through hole, and when the coil is powered off, the first ring groove is communicated with the third through hole.

3. The hydraulic machine pressure control system according to claim 2, wherein the inner side wall of the second sliding hole is provided with a second ring groove, and a fourth through hole for communicating the second ring groove and the communication cavity is arranged in the valve sleeve; and fifth through holes for communicating the port P with the second annular groove are formed in the valve core and the plug body.

4. The hydraulic machine pressure control system according to claim 1, wherein a stud is connected in the plug in a threaded manner, a mandril which passes through the armature and extends into the control cavity is arranged at the lower end of the stud, the upper end of the second spring abuts against the lower end of the mandril through a spring pad, and the lower end of the second spring abuts against the upper end of the plug body.

5. The pressure control system of the hydraulic machine as claimed in claim 1, wherein a rod chamber is formed between the upper end of the first sliding hole and the spool, and a communication hole communicating with the rod chamber is provided in a side surface of the valve housing.

6. The hydraulic machine pressure control system of claim 1 wherein the plug is threadably connected to a limit nut and the coil is positioned between the limit nut and the upper threaded sleeve.

Technical Field

The invention belongs to the technical field of valves, and particularly relates to a hydraulic machine pressure control system and a control method.

Background

The hydraulic press is a machine for processing products such as metal, plastic, rubber, wood, powder and the like by using hydrostatic pressure. It is commonly used in press processes and press forming processes, such as: forging, stamping, cold extruding, straightening, bending, flanging, sheet drawing, powder metallurgy, press fitting and the like. The existing hydraulic machines are divided into four-column type, horizontal type, vertical type and multilayer steel strip winding frames according to the structural form. Wherein: the medium and small vertical hydraulic machines usually use a single column type, also called C-shaped frame type, and the single column type hydraulic machine has three open sides and is convenient to operate. In order to protect the hydraulic machine from overload, a pressure protection device is usually arranged on a hydraulic system of the hydraulic machine to limit the highest output pressure of the hydraulic system, and the pressure protection device of the existing hydraulic machine usually adopts a safety valve. However, in order to reduce the energy consumption of the hydraulic machine and protect the motor, the hydraulic pump of the hydraulic system is generally started in no-load mode, that is, when the hydraulic pump is started, the hydraulic system is unloaded, so that no pressure exists at the outlet of the hydraulic pump, so that an electromagnetic valve is connected in parallel with a safety valve in a hydraulic pump station, the electromagnetic valve plays an unloading role, the safety valve is connected in parallel with the electromagnetic valve, the cost of the hydraulic machine is increased, the complexity and the overall volume of pipeline connection are increased, and the integrated design of the miniaturization of the hydraulic machine is not facilitated.

Disclosure of Invention

The invention aims to provide a hydraulic machine pressure control system which is simple in structure and can realize the functions of a safety valve and a pressure release valve.

In order to achieve the purpose, the invention provides the following technical scheme:

a pressure control system of a hydraulic machine comprises a plug, wherein a vertically-penetrating mounting hole is formed in the plug, a valve sleeve is fixedly mounted at the lower end of the mounting hole, a first sliding hole and a second sliding hole are sequentially formed in the valve sleeve from bottom to top along the axial direction of the mounting hole, the upper end of the second sliding hole is communicated with the mounting hole, the first sliding hole and the second sliding hole are communicated and coaxially arranged, a lower screw sleeve is fixedly mounted at the opening at the lower end of the first sliding hole, the lower end of the lower screw sleeve is a P port, a T port communicated with the first sliding hole is formed in the side surface of the valve sleeve, a valve core used for controlling the connection and disconnection of the P port and the T port is slidably connected in the first sliding hole, a plug body extending into the second sliding hole is arranged on the valve core, and the diameter of the valve core is larger than that of the plug body; an upper threaded sleeve is fixedly mounted at the upper end of the mounting hole, a magnetic conduction pipe is fixedly mounted at an opening at the upper end of the upper threaded sleeve, a plug is fixedly mounted at the upper end of the magnetic conduction pipe, an armature is connected in the magnetic conduction pipe in a sliding manner, a sliding sleeve extending into the mounting hole is fixedly mounted at the lower end of the armature, a first spring for forcing the armature to move downwards is arranged between the armature and the plug in the magnetic conduction pipe, and a coil is arranged on the outer side of the magnetic conduction pipe; a control cavity is formed between the sliding sleeve and the valve sleeve in the mounting hole, and a second spring for forcing the plug body to move downwards is arranged in the control cavity; when the coil is electrified, the armature moves upwards and compresses the second spring, and the control cavity is communicated with the T port; when the coil is powered off, the armature moves downwards under the action of the second spring, and the control cavity is communicated with the port P.

Furthermore, a first ring groove is formed in the side face of the outer circumference of the sliding sleeve, and a first through hole for communicating the control cavity with the first ring groove is formed in the side wall of the sliding sleeve; a second through hole for communicating the mounting hole with the T port is formed in the plug; a communicating cavity communicated with the port P is formed at the upper end of the valve sleeve in the plug, and a third through hole used for communicating the communicating cavity with the mounting hole is formed in the plug; when the coil is electrified, the first ring groove is communicated with the second through hole, and when the coil is powered off, the first ring groove is communicated with the third through hole.

Further, a second ring groove is formed in the inner side wall of the second sliding hole, and a fourth through hole for communicating the second ring groove with the communicating cavity is formed in the valve sleeve; and fifth through holes for communicating the port P with the second annular groove are formed in the valve core and the plug body.

Furthermore, a stud is connected with the inner thread of the plug, a mandril which penetrates through the armature and extends into the control cavity is arranged at the lower end of the stud, the upper end of the second spring is abutted against the lower end of the mandril through a spring pad, and the lower end of the second spring is abutted against the upper end of the plug body; the set pressure of the second spring can be adjusted by rotating the stud, and the set safety pressure can be changed by rotating the stud to change the compression amount of the second spring.

Furthermore, a rod cavity is formed between the upper end of the first sliding hole and the valve core, and a communication hole communicated with the rod cavity is formed in the side face of the valve sleeve.

Furthermore, the plug is connected with a limit nut in a threaded manner, and the coil is located between the limit nut and the upper threaded sleeve.

The invention also provides a control method of the hydraulic press pressure control system, when the hydraulic press pressure control system plays a role of safety protection, the control coil is powered off, the armature moves downwards under the action of the first spring to enable the first ring groove to be communicated with the third through hole, at the moment, the control cavity is communicated with the P port through the first through hole, the first ring groove, the third through hole, the communication cavity, the fourth through hole, the second ring groove and the fifth through hole, so that the upper pressure and the lower pressure of the plug body are equal, at the moment, because the area of the valve core is larger than the area of the plug column, the pressure of the P port generates upward thrust on the valve core, when the action force generated by the pressure of the P port on the valve core is larger than the action force of the second spring, the valve core moves upwards to enable the P port to be communicated with the T port, so that the overflow protection effect is achieved; when the pressure of the port P is reduced, the valve core moves downwards and tightly presses the upper end of the lower threaded sleeve to separate the port P from the port T again under the action of a second spring;

when the hydraulic press pressure control system needs unloading, the control coil is electrified, the armature moves upwards under the action of a magnetic field and compresses the first spring, so that the first annular groove is communicated with the second through hole, the control cavity is communicated with the T port through the first through hole, the first annular groove and the second through hole at the moment, the upward force of the valve core is far greater than the pre-tightening force of the first spring under the action of the pressure of the P port on the valve core, the valve core can move upwards to open the valve port under the very small pressure of the P port, and the unloading function is achieved.

Advantageous effects

Compared with the prior art, the technical scheme of the invention has the following advantages:

(1) according to the hydraulic press pressure control system, when the coil is not electrified, the hydraulic press pressure control system plays a role of a safety valve and can limit the highest pressure of the hydraulic press; when the coil is electrified, the invention plays the role of an unloading valve, and can unload the pressure at the outlet of the hydraulic pump, so that the hydraulic pump is started in no-load, the energy consumption is reduced, and the motor is protected;

(2) the invention has compact volume, simple structure and low use cost, and simplifies the pipeline of the hydraulic system of the hydraulic machine.

Drawings

FIG. 1 is a block diagram of the present invention, now in a secure functional state;

fig. 2 is a block diagram of the present invention, now in an unloaded state.

Detailed Description

Referring to fig. 1-2, a pressure control system of a hydraulic machine includes a plug 4, a mounting hole 4a penetrating up and down is provided in the plug 4, a valve sleeve 2 is fixedly mounted at a lower end of the mounting hole 4a, a first sliding hole 2a and a second sliding hole 2b are sequentially provided in the valve sleeve 2 from bottom to top along an axial direction of the mounting hole, an upper end of the second sliding hole 2b is communicated with the mounting hole 4a, the first sliding hole 2a and the second sliding hole 2b are communicated and coaxially disposed, a lower threaded sleeve 1 is fixedly mounted at an opening at a lower end of the first sliding hole 2a, a P port is provided at a lower end of the lower threaded sleeve 1, a T port communicated with the first sliding hole 2a is provided at a side surface of the valve sleeve 2, a valve core 31 for controlling the connection and disconnection of the P port and the T port is slidably connected in the first sliding hole 2a, a plug body 3 extending into the second sliding hole 2b is provided on the valve core 31, the diameter D1 of the valve core 31 is larger than the diameter D2 of the plug body 3; an upper threaded sleeve 71 is fixedly mounted at the upper end of the mounting hole 4a, a magnetic conduction pipe 7 is fixedly mounted at an opening at the upper end of the upper threaded sleeve 71, a plug 8 is fixedly mounted at the upper end of the magnetic conduction pipe 7, an armature 10 is slidably connected in the magnetic conduction pipe 7, a sliding sleeve 5 extending into the mounting hole 4a is fixedly mounted at the lower end of the armature 10, a first spring 11 for forcing the armature 10 to move downwards is arranged between the armature 10 and the plug 8 in the magnetic conduction pipe 7, a coil 12 is arranged on the outer side of the magnetic conduction pipe 7, a limit nut 81 is connected to the plug 8 in a threaded manner, and the coil 12 is positioned between the limit nut 81 and the upper threaded sleeve 71; a control cavity 4b is formed between the sliding sleeve 5 and the valve sleeve 2 in the mounting hole 4a, and a second spring 6 for forcing the plug body 3 to move downwards is arranged in the control cavity 4 b; when the coil 12 is electrified, the armature 10 moves upwards and compresses the second spring 6, and the control cavity 4b is communicated with the T port; when the coil 12 is de-energized, the armature 10 moves downwards under the action of the second spring 6, and the control chamber 4b is communicated with the port P. A rod chamber 2c is formed between the upper end of the first slide hole 2a and the valve core 31, and a communication hole 2d communicated with the rod chamber 2c is formed in the side surface of the valve housing 2.

The side surface of the outer circumference of the sliding sleeve 5 is provided with a first annular groove 51, and the side wall of the sliding sleeve 5 is provided with a first through hole 52 for communicating the control cavity 4b with the first annular groove 51; a second through hole 41 for communicating the mounting hole 4a with the T port is formed in the plug 4; a communicating cavity 4c communicated with the port P is formed in the upper end of the valve sleeve 2 in the plug 4, and a third through hole 42 used for communicating the communicating cavity 4c with the mounting hole 4a is formed in the plug 4; when the coil 12 is energized, the first ring groove 51 communicates with the second through hole 41, and when the coil 12 is de-energized, the first ring groove 51 communicates with the third through hole 42. A second ring groove 21 is formed in the inner side wall of the second sliding hole 2b, and a fourth through hole 22 for communicating the second ring groove 21 with the communication cavity 4c is formed in the valve sleeve 2; and a fifth through hole 32 for communicating the port P with the second annular groove 21 is formed in the valve core 31 and the plug body 3.

A stud 9 is connected with the plug 8 through an internal thread, a push rod 91 which penetrates through the armature 10 and extends into the control cavity 4b is arranged at the lower end of the stud 9, the upper end of the second spring 6 abuts against the lower end of the push rod 91 through a spring pad 61, and the lower end of the second spring 6 abuts against the upper end of the plug body 3; the set pressure of the second spring 6 can be adjusted by rotating the stud 9, and the set safety pressure can be changed by changing the compression amount of the second spring 6 by rotating the stud 9.

The invention also provides a control method of the hydraulic press pressure control system, when the hydraulic press pressure control system plays a role of safety protection, the control coil 12 is powered off, under the action of the first spring 11, the armature 10 moves downwards, so that the first annular groove 51 is communicated with the third through hole 42, at the moment, the control cavity 4b is communicated with the port P through the first through hole 52, the first annular groove 51, the third through hole 42, the communication cavity 4c, the fourth through hole 22, the second annular groove 21 and the fifth through hole 32, so that the upper pressure and the lower pressure of the plug body 3 are equal, at the moment, because the area of the valve core 31 is larger than that of the plug column, the pressure of the port P generates upward thrust on the valve core 31, when the force generated by the P port pressure acting on the spool 31 is larger than the force of the second spring 6, the valve core 31 moves upwards to communicate the port P with the port T, so that the overflow protection effect is achieved, and the pressure of the port P cannot rise continuously; when the pressure of the port P is reduced, the valve core 31 moves downwards to press the upper end of the lower screw sleeve 2 to separate the port P from the port T again under the action of the second spring 6.

In addition, when the hydraulic press pressure control system needs unloading, the control coil 12 is electrified, the armature 10 moves upwards under the action of a magnetic field and compresses the first spring 11, so that the first annular groove 51 is communicated with the second through hole 41, the control cavity 4b is communicated with the T port through the first through hole 52, the first annular groove 51 and the second through hole 41, the upward force of the valve core 31 is far greater than the pretightening force of the first spring 11 under the action of the pressure of the P port on the valve core 31, so that the valve core 31 can move upwards to open the valve port under the small pressure of the P port, and the unloading function is achieved.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the technical principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.