CN108454151B

CN108454151B - Energy-saving hydraulic press

Info

Publication number: CN108454151B
Application number: CN201810115803.XA
Authority: CN
Inventors: 乔礼惠; 陆烨
Original assignee: Yangli Group Corp ltd
Current assignee: Yangli Group Corp ltd
Priority date: 2018-02-06
Filing date: 2018-02-06
Publication date: 2023-05-30
Anticipated expiration: 2038-02-06
Also published as: CN108454151A

Abstract

The invention relates to an energy-saving hydraulic machine, wherein the bottom center of a hydraulic cushion is connected with a hydraulic cushion piston cylinder, four corners of the hydraulic cushion are respectively connected with the top of the hydraulic cushion piston cylinder, the outlet of a servo pump is respectively connected with a hydraulic cushion control oil way, an eleventh cartridge valve and the inlets of a twentieth cartridge valve, the eleventh cartridge valve is controlled by an eighth electromagnetic reversing valve, and the outlet of the eleventh cartridge valve is connected with an energy accumulator; the outlet of the twenty-first cartridge valve is connected with the oil way of the lower cavity of the main cylinder of the sliding block, the twenty-first cartridge valve is controlled by the sixteenth electromagnetic reversing ball valve, and the eighth electromagnetic reversing ball valve and the sixteenth electromagnetic reversing ball valve are two-position three-way electromagnetic reversing valves. The bottom of the energy accumulator is connected with the inlet of a ninth cartridge valve, the outlet of the ninth cartridge valve is connected with the inlet of an eighth cartridge valve, and the outlet of the eighth cartridge valve is connected with the total oil pipe of each hydraulic cushion plunger cylinder. The hydraulic machine can pre-charge the energy accumulator by utilizing the oil outlet of the lower cavity when the sliding block is fast lowered, so that energy sources can be effectively saved, and the sliding block is fast lowered to smoothly transition in work.

Description

Energy-saving hydraulic press

Technical Field

The invention relates to a hydraulic machine, in particular to an energy-saving hydraulic machine, and belongs to the technical field of machine tool control systems.

Background

The hydraulic cushion action control of the current hydraulic press basically follows the control of the slide block, namely the hydraulic press slide block motion control and the hydraulic cushion motion control share a hydraulic pump station, and the action of the hydraulic cushion can be carried out only after the slide block action is stopped due to the existence of a shared pump source in the action process, so that a plurality of users hope to synchronously eject the hydraulic cushion in the process of the slide block return stroke, and the waiting time can be reduced while the return stroke speed of the slide block is not influenced, thereby improving the production efficiency.

Some manufacturers deliberately control the sliding block movement and the hydraulic cushion movement of the hydraulic machine by adopting two groups of pump stations according to the requirements of customers, namely, the operation control of the sliding block is controlled by an upper pump station, the up-down control of the hydraulic cushion is controlled by a lower pump station, and the two groups of pump stations are in a completely independent state, so that the installed power is increased, the investment cost is increased, and the energy waste is caused. Under the condition, individual manufacturers change the driving oil cylinders of the hydraulic cushion into a multi-cylinder structure, usually a mode of a middle piston cylinder and two side plunger cylinders, oil is supplied to the middle piston cylinder through an oil pump so as to drive the hydraulic cushion to move upwards, the peripheral plunger cylinders realize quick ejection by means of oil supplementing through a one-way valve, and when the hydraulic cushion moves to be close to an upper limit, oil is supplied to all the oil cylinders through the oil pump, so that full tonnage ejection is realized, but a pause phenomenon occurs when the quick ejection rotates to full tonnage ejection, even small-amplitude falling occurs, ejection speed conversion is unstable, and the phenomenon is caused by the fact that the plunger cylinders only rely on negative pressure oil supplementing in the quick ejection process.

Disclosure of Invention

The invention aims to overcome the problems in the prior art and provide an energy-saving hydraulic machine, which can fully utilize the energy of a slide block during quick descending and realize the stable transition of the quick descending operation of the slide block.

In order to solve the technical problems, the energy-saving hydraulic machine comprises a sliding block 1 and a hydraulic cushion 2, wherein the top center of the sliding block 1 is connected to the lower end of a sliding block plunger cylinder 1b, sliding block main cylinders 1a are symmetrically arranged on the left side and the right side of the sliding block plunger cylinder 1b, and the lower ends of pistons of the sliding block main cylinders 1a are respectively connected with the sliding block 1; the center of the bottom of the hydraulic cushion 2 is connected with a hydraulic cushion piston cylinder 2a, four corners of the hydraulic cushion 2 are respectively connected with the top of a hydraulic cushion plunger cylinder 2B, an inlet of a servo pump B1 is connected with an oil tank, an outlet of the servo pump B1 is connected with an inlet of a first one-way valve D1, an outlet of the first one-way valve D1 is respectively connected with a hydraulic cushion control oil path, an inlet of an eleventh cartridge valve C11 and an inlet of a twentieth cartridge valve C20, a hydraulic control port of the eleventh cartridge valve C11 is connected with a P port of an eighth electromagnetic reversing valve YV8, an A port of the eighth electromagnetic reversing valve YV8 is connected with an inlet of the twentieth cartridge valve C20, a B port of the eighth electromagnetic reversing valve YV8 is connected with the oil tank, the eighth electromagnetic reversing valve YV8 is a two-position four-way electromagnetic reversing valve, and an outlet of the eleventh cartridge valve C11 is connected with an accumulator AC; the outlet of the twenty-first cartridge valve C20 is connected with the oil way G1 of the lower cavity of the main cylinder of the sliding block, the hydraulic control port of the twenty-first cartridge valve C20 is connected with the A port of the sixteenth electromagnetic reversing ball valve YV16, the P port of the sixteenth electromagnetic reversing ball valve YV16 is connected with the outlet of the twenty-first cartridge valve C20, the T port of the sixteenth electromagnetic reversing ball valve YV16 is connected with the inlet of the twenty-first cartridge valve C20, and the sixteenth electromagnetic reversing ball valve YV16 is a two-position three-way electromagnetic reversing valve.

Compared with the prior art, the invention has the following beneficial effects: the hydraulic cushion driving cylinder adopts a structure that the hydraulic cushion piston cylinder 2a positioned in the center and the four corners are respectively provided with the hydraulic cushion plunger cylinder 2b, so that the stretching force of the hydraulic cushion 2 is uniformly distributed, and four corners of the stretching force of the hydraulic cushion can be respectively adjustable through the cooperation of a hydraulic system and an electric control system. The structural characteristics of the slider main cylinder 1a and the slider plunger cylinder 1b are fully utilized, when the slider 1 is fast down, the sixteenth electromagnetic reversing ball valve YV16 is powered on, and the twentieth cartridge valve C20 is opened; meanwhile, the eighth electromagnetic directional valve YV8 is powered on, the eleventh cartridge valve C11 is opened, oil discharged from the rod cavity of the slider main cylinder 1a is pre-pressurized to the accumulator AC through the oil way G1 of the lower cavity of the slider main cylinder, the twentieth cartridge valve C20 and the eleventh cartridge valve C11, so that the weight of the slider 1 is balanced, the smooth transition of the fast-down operation of the slider is realized, and the energy conversion is fully realized.

As an improvement of the invention, the hydraulic cushion control oil way comprises a first to a ninth cartridge valves, the bottom of the accumulator AC is connected with the inlet of the ninth cartridge valve C9, the outlet of the ninth cartridge valve C9 is connected with the inlet of the eighth cartridge valve C8, and the outlet of the eighth cartridge valve C8 is connected with the total oil pipe of each hydraulic cushion plunger cylinder 2 b; the eighth cartridge valve C8 is provided with an opening adjusting handle, the hydraulic control port of the ninth cartridge valve C9 is connected with the A port of the seventh electromagnetic directional valve YV7, the seventh electromagnetic directional valve YV7 is a two-position four-way electromagnetic directional valve, the P port of the seventh electromagnetic directional valve YV7 is connected with the inlet of the ninth cartridge valve C9, and the T port of the seventh electromagnetic directional valve YV7 is connected with an oil tank. When the hydraulic cushion 2 is rapidly ejected, the eighth electromagnetic reversing valve YV8 and the sixteenth electromagnetic reversing ball valve YV16 are powered off, and the eleventh cartridge valve C11 and the twentieth cartridge valve C20 are closed; the seventh electromagnetic reversing valve YV7 is electrified, the ninth cartridge valve C9 is opened, the flow is regulated by regulating the opening regulating handle of the eighth cartridge valve C8, and the pressure oil stored in the accumulator AC enters the four hydraulic cushion plunger cylinders 2b through the ninth cartridge valve C9 and the eighth cartridge valve C8, so that the hydraulic cushion plunger cylinders 2b positioned around are rapidly supplemented by the accumulator AC. Because the hydraulic cushion plunger cylinder 2b is subjected to quick oil filling with pressure by the accumulator AC during ejection operation, the phenomenon of falling and stopping during quick ejection to slow ejection is eliminated, and the whole ejection movement realizes stable transition. And by combining the servo pump control technology, the accurate control of pressure and torque can be realized, and the energy is effectively saved.

As a further improvement of the invention, the inlets of the third cartridge valve C3 and the fifth cartridge valve C5 are respectively connected with the outlet of the first check valve D1, the outlet of the third cartridge valve C3 is respectively connected with the inlets of the first cartridge valve C1, the second cartridge valve C2 and the fourth cartridge valve C4, the outlet of the first cartridge valve C1 is connected with the lower cavity of the hydraulic cushion piston cylinder 2a, and the outlet of the second cartridge valve C2 and the inlet of the seventh cartridge valve C7 are respectively connected with the oil ports of the hydraulic cushion plunger cylinder 2 b; the outlet of the fifth cartridge valve C5 is respectively connected with the inlet of the sixth cartridge valve C6 and the upper cavity of the hydraulic cushion piston cylinder 2a, the outlets of the fourth cartridge valve C4, the sixth cartridge valve C6 and the seventh cartridge valve C7 are respectively connected with an oil tank, and a hydraulic cushion displacement sensor S1 is arranged on one side of the hydraulic cushion 2. Hydraulic cushion fast roof: the hydraulic cushion 2 is rapidly ejected, the ninth cartridge valve C9 is opened, the first cartridge valve C1 and the third cartridge valve C3 are opened, pressure oil output by the servo pump B1 sequentially flows through the third cartridge valve C3 and the first cartridge valve C1 to enter the lower cavity of the hydraulic cushion piston cylinder 2a, and oil in the upper cavity of the hydraulic cushion piston cylinder 2a flows back to the oil tank through the sixth cartridge valve C6. Hydraulic cushion slow top: when the hydraulic cushion displacement sensor S1 detects that the hydraulic cushion 2 rises to a set position, the seventh electromagnetic directional valve YV7 is powered off to enable the ninth cartridge valve C9 to be closed, the accumulator AC stops supplementing oil to the four hydraulic cushion plunger cylinders 2B, the second cartridge valve C2 is opened, pressure oil output by the servo pump B1 enters the hydraulic cushion plunger cylinders 2a and the four hydraulic cushion plunger cylinders 2B at the same time, the hydraulic cushion 2 is ejected slowly, and ejection control of the hydraulic cushion 2 can be achieved by adopting the servo pump B1 with small displacement. The servo pump B1 is combined with the hydraulic cushion displacement sensor S1, and accurate control of the ejection position of the hydraulic cushion 2 can be realized through closing operation control, so that the one-time forming rate of parts is improved. The cylinders of the hydraulic cushion retract: the first cartridge valve C1 and the second cartridge valve C2 are kept open, the third cartridge valve C3 is closed, the fourth cartridge valve C4 is opened, and oil in the lower cavity of the hydraulic cushion piston cylinder 2a returns to the oil tank through the first cartridge valve C1 and the fourth cartridge valve C4; meanwhile, the seventh cartridge valve C7 is opened, and oil in the hydraulic cushion plunger cylinder 2b returns to the oil tank through the second cartridge valve C2, the fourth cartridge valve C4 and the seventh cartridge valve C7. The hydraulic cushion is stretched, and each cylinder is forced to retract: the first cartridge valve C1, the second cartridge valve C2 and the fourth cartridge valve C4 are kept open, the seventh cartridge valve C7 is closed, and oil in the lower cavity of the hydraulic cushion piston cylinder 2a returns to the oil tank through the first cartridge valve C1 and the fourth cartridge valve C4; the oil in the hydraulic cushion plunger cylinder 2b passes through the second cartridge valve C2 and the fourth cartridge valve C4 to return to the oil tank, and the stretching force is controlled by the fourth cartridge valve C4.

As a further improvement of the invention, the hydraulic control port of the first cartridge valve C1 is connected with the A port of the first electromagnetic reversing ball valve YV1, the first electromagnetic reversing ball valve YV1 is a two-position three-way electromagnetic reversing valve, the P port of the first electromagnetic reversing ball valve YV1 is connected with the outlet of the first cartridge valve C1, and the T port of the first electromagnetic reversing ball valve YV1 is connected with an oil tank; the hydraulic control port of the second cartridge valve C2 is connected with the A port of the second electromagnetic directional valve YV2, the second electromagnetic directional valve YV2 is a two-position four-way electromagnetic directional valve, the P port of the second electromagnetic directional valve YV2 is connected with the inlet of the second cartridge valve C2, and the T port of the second electromagnetic directional valve YV2 is connected with an oil tank; the hydraulic control port of the third cartridge valve C3 is connected with the middle outlet of the first shuttle valve SF1, the right inlet of the first shuttle valve SF1 is connected with the outlet of the third cartridge valve C3, the left inlet of the first shuttle valve SF1 is connected with the A port of the third electromagnetic directional valve, the third electromagnetic directional valve is a three-position four-way electromagnetic directional valve with the middle position function of P, and the B port of the third electromagnetic directional valve is connected with the hydraulic control port of the fifth cartridge valve C5; the P port of the third electromagnetic directional valve is connected with the outlet of the fourth cartridge valve C4, the T port of the third electromagnetic directional valve is connected with the outlet of the third one-way valve D3, and the inlet of the third one-way valve D3 is connected with the inlet of the fifth cartridge valve C5; the port B of the third electromagnetic directional valve is connected with the inlet of a second one-way valve D2, the outlet of the second one-way valve D2 is connected with the hydraulic control port of a fourth cartridge valve C4, and the hydraulic control port of the fourth cartridge valve C4 is also connected with an oil tank through a third pressure regulating valve F3; the port A of the third electromagnetic directional valve is also connected with the outlet of a fourth one-way valve D4, the inlet of the fourth one-way valve D4 is connected with the hydraulic control port of a sixth cartridge valve C6, and the hydraulic control port of the sixth cartridge valve C6 is also connected with an oil tank through a fourth pressure regulating valve F4; the hydraulic control port of the seventh cartridge valve C7 is connected with the port B of the fifth electromagnetic directional valve YV5, the fifth electromagnetic directional valve YV5 is a two-position four-way electromagnetic directional valve, and the port T of the fifth electromagnetic directional valve YV5 is connected with the outlet of the seventh cartridge valve C7. Hydraulic cushion fast roof: the hydraulic cushion 2 is rapidly ejected, the ninth cartridge valve C9 is opened, the first electromagnetic reversing ball valve YV1 is powered on, and the first cartridge valve C1 is opened; the left electromagnet YV4 of the third electromagnetic reversing valve is electrified, and the third cartridge valve C3 is opened; the pressure oil output by the servo pump B1 sequentially flows through the third cartridge valve C3 and the first cartridge valve C1 to enter the lower cavity of the hydraulic cushion piston cylinder 2a, and the oil in the upper cavity of the hydraulic cushion piston cylinder 2a flows back to the oil tank through the sixth cartridge valve C6. Hydraulic cushion slow top: when the hydraulic cushion displacement sensor S1 detects that the hydraulic cushion 2 rises to the set position, the seventh electromagnetic reversing valve YV7 is powered off to close the ninth cartridge valve C9, and the accumulator AC stops supplementing oil to the four hydraulic cushion plunger cylinders 2 b; the second electromagnetic reversing valve YV2 is electrified to enable the second cartridge valve C2 to be opened, pressure oil output by the servo pump B1 simultaneously enters the hydraulic cushion piston cylinder 2a and the four hydraulic cushion piston cylinders 2B, the hydraulic cushion 2 is slowly ejected, and ejection control of the hydraulic cushion 2 can be realized by adopting the small-displacement servo pump B1. The servo pump B1 is combined with the hydraulic cushion displacement sensor S1, and accurate control of the ejection position of the hydraulic cushion 2 can be realized through closing operation control, so that the one-time forming rate of parts is improved. The cylinders of the hydraulic cushion retract: the first electromagnetic reversing ball valve YV1 and the second electromagnetic reversing valve YV2 are kept powered, so that the first cartridge valve C1 and the second cartridge valve C2 are kept open; the right electromagnet YV3 of the third electromagnetic reversing valve is electrified to close the third cartridge valve C3; the fourth cartridge valve C4 is opened due to pressure relief of the hydraulic control port, and oil in the lower cavity of the hydraulic cushion piston cylinder 2a returns to the oil tank through the first cartridge valve C1 and the fourth cartridge valve C4; meanwhile, the seventh cartridge valve C7 is opened by the power supply of the fifth electromagnetic directional valve YV5, and oil in the hydraulic cushion plunger cylinder 2b returns to the oil tank through the second cartridge valve C2, the fourth cartridge valve C4 and the seventh cartridge valve C7. The hydraulic cushion is stretched, and each cylinder is forced to retract: the first electromagnetic reversing ball valve YV1 and the second electromagnetic reversing valve YV2 are kept powered, so that the first cartridge valve C1 and the second cartridge valve C2 are kept open; the right electromagnet YV3 is powered off to enable the third electromagnetic reversing valve to return to the middle position, and the fourth cartridge valve C4 is kept open; the fifth electromagnetic reversing valve YV5 is powered off to enable the seventh cartridge valve C7 to be closed, and oil in the lower cavity of the hydraulic cushion piston cylinder 2a returns to the oil tank through the first cartridge valve C1 and the fourth cartridge valve C4; the oil in the hydraulic cushion plunger cylinder 2b passes through the second cartridge valve C2 and the fourth cartridge valve C4 to return to the oil tank, and the stretching force is controlled by the third pressure regulating valve F3 of the fourth cartridge valve C4.

As a further improvement of the present invention, the main oil pump outlet line G2 is connected to the inlets of the thirteenth cartridge valve C13, the fourteenth cartridge valve C14 and the fifteenth cartridge valve C15, respectively, the outlet of the thirteenth cartridge valve C13 is connected to the inlet of the twelfth cartridge valve C12, and the outlet of the twelfth cartridge valve C12 is connected to the upper chambers of the slider plunger cylinder 1b and the slider master cylinder 1 a; the outlet of the fifteenth cartridge valve C15 is respectively connected with the inlets of the sixteenth cartridge valve C16, the seventeenth cartridge valve C17, the eighteenth cartridge valve C18 and the nineteenth cartridge valve C19, the outlet of the eighteenth cartridge valve C18 is connected with the lower cavity oil path G1 of the slider main cylinder, and the outlets of the fourteenth cartridge valve C14, the sixteenth cartridge valve C16, the seventeenth cartridge valve C17 and the nineteenth cartridge valve C19 are respectively connected with the oil tank. The first-stage quick-down of the sliding block: the thirteenth cartridge valve C13 is opened, and oil is fed into the upper cavity of the slider main cylinder 1a and the slider plunger cylinder 1b through the thirteenth cartridge valve C13 and the twelfth cartridge valve C12; the sixteenth cartridge valve C16, the seventeenth cartridge valve C17 and the eighteenth cartridge valve C18 are opened; a nineteenth cartridge valve C19 support; the twentieth cartridge valve C20 is opened, the eleventh cartridge valve C11 is opened, and the discharged oil of the rod cavity of the slider master cylinder 1a is pre-charged to the accumulator AC through the slider master cylinder lower cavity oil path G1, the twentieth cartridge valve C20 and the eleventh cartridge valve C11. The second-stage fast-down of the sliding block: the rest remains unchanged, the sixteenth cartridge valve C16 is closed, ready for a slow transition to the slider. The sliding block is slowly arranged: the rest is kept unchanged, the twentieth cartridge valve C20 is closed, and the pre-charging of the accumulator AC by the oil way G1 of the lower cavity of the main cylinder of the sliding block is finished; the servo pump B1 continues to charge the accumulator AC through the eleventh cartridge valve C11, and after the charging is completed, the eleventh cartridge valve C11 and the seventeenth cartridge valve C17 are closed to prepare for the slider to be pressurized. And (3) carrying out slider working pressurization: the supporting force of the lower chamber of the slider master cylinder 1a is controlled by a nineteenth cartridge valve C19. Decompression is performed after the pressure maintaining of the sliding block: the thirteenth cartridge valve C13, the eighteenth cartridge valve C18, and the nineteenth cartridge valve C19 are closed, and the remaining cartridge valves are held. Slider return stroke: the fourteenth cartridge valve C14 is closed, and the pressure of the main oil pump outlet pipeline G2 is built; the fifteenth cartridge valve C15 is opened and the pressurized oil of the main oil pump outlet line G2 passes through the fifteenth cartridge valve C15 and pushes open the eighteenth cartridge valve C18 into the lower chamber of the slider master cylinder 1 a.

As a further improvement of the invention, the hydraulic control port of the thirteenth cartridge valve C13 is connected with the A port of the ninth electromagnetic directional valve YV9, the P port of the ninth electromagnetic directional valve YV9 is connected with the inlet of the thirteenth cartridge valve C13, and the T port of the ninth electromagnetic directional valve YV9 is connected with the oil tank; the hydraulic control port of the fourteenth cartridge valve C14 is connected with the port B of the tenth electromagnetic directional valve YV 10; the hydraulic control port of the fifteenth cartridge valve C15 is connected with the middle outlet of the second shuttle valve SF2, the left inlet of the second shuttle valve SF2 is connected with the outlet of the fifteenth cartridge valve C15, the right inlet of the second shuttle valve SF2 is connected with the A port of the eleventh electromagnetic directional valve YV11, and the P port of the eleventh electromagnetic directional valve YV11 is connected with the inlet of the fifteenth cartridge valve C15; the hydraulic control port of the sixteenth cartridge valve C16 is connected with the A port of the twelfth electromagnetic directional valve YV12, and the P port of the twelfth electromagnetic directional valve YV12 is connected with the inlet of the sixteenth cartridge valve C16; the hydraulic control port of the seventeenth cartridge valve C17 is connected with the A port of the thirteenth electromagnetic directional valve YV13, and the P port of the thirteenth electromagnetic directional valve YV13 is connected with the inlet of the seventeenth cartridge valve C17; the hydraulic control port of the eighteenth cartridge valve C18 is connected with the A port of the fourteenth electromagnetic reversing ball valve YV14, and the P port of the fourteenth electromagnetic reversing ball valve YV14 is connected with the outlet of the eighteenth cartridge valve C18; the hydraulic control port of the eighteenth cartridge valve C18 is connected with the A port of the fifteenth electromagnetic directional valve YV15, is connected with the P port of the fifteenth electromagnetic directional valve YV15 through a ninth pressure regulating valve F9, and is connected with the B port of the fifteenth electromagnetic directional valve YV15 through a tenth pressure regulating valve F10; the port T of the tenth electromagnetic directional valve YV10, the eleventh electromagnetic directional valve YV11, the twelfth electromagnetic directional valve YV12, the thirteenth electromagnetic directional valve YV13 and the fourteenth electromagnetic directional ball valve YV14 are respectively connected with an oil tank, and the port B of the fifteenth electromagnetic directional valve YV15 is connected with the oil tank; the fourteenth electromagnetic reversing ball valve YV14 is a two-position three-way electromagnetic reversing valve, and the tenth, eleventh, twelfth, thirteenth and fifteenth electromagnetic reversing valves are two-position four-way electromagnetic reversing valves. The first-stage quick-down of the sliding block: the thirteenth cartridge valve C13 is opened by powering the ninth electromagnetic directional valve YV9, and oil is fed into the upper cavity of the slider main cylinder 1a and the slider plunger cylinder 1b through the thirteenth cartridge valve C13 and the twelfth cartridge valve C12; the twelfth electromagnetic directional valve YV12 is powered to enable the sixteenth cartridge valve C16 to be opened, the thirteenth electromagnetic directional valve YV13 is powered to enable the seventeenth cartridge valve C17 to be opened, and the fourteenth electromagnetic directional ball valve YV14 is powered to enable the eighteenth cartridge valve C18 to be opened; the fifteenth electromagnetic directional valve YV15 is powered to enable the nineteenth cartridge valve C19 to obtain the support of the ninth pressure regulating valve F9; the sixteenth electromagnetic reversing ball valve YV16 is powered to enable the twentieth cartridge valve C20 to be opened, the eighth electromagnetic reversing valve YV8 is powered to enable the eleventh cartridge valve C11 to be opened, and oil discharged from the rod cavity of the slider main cylinder 1a is subjected to pre-charging on the accumulator AC through the slider main cylinder lower cavity oil way G1, the twentieth cartridge valve C20 and the eleventh cartridge valve C11. The second-stage fast-down of the sliding block: the rest is kept unchanged, the twelfth electromagnetic reversing valve YV12 is powered off to enable the sixteenth cartridge valve C16 to be closed, and the sliding block is ready to be slowly transited. The sliding block is slowly arranged: the rest is kept unchanged, the sixteenth electromagnetic reversing ball valve YV16 is powered off to enable the twentieth cartridge valve C20 to be closed, and the pre-charging of the accumulator AC by the oil way G1 of the lower cavity of the main cylinder of the sliding block is finished; the servo pump B1 continuously charges the accumulator AC through an eleventh cartridge valve C11, after the charging is completed, the eighth electromagnetic directional valve YV8 is powered off, the eleventh cartridge valve C11 is closed, the thirteenth electromagnetic directional valve YV13 is powered off, the seventeenth cartridge valve C17 is closed, and the slide block is ready to be charged for pressurization. And (3) carrying out slider working pressurization: the supporting force of the lower chamber of the slider master cylinder 1a is controlled by a nineteenth cartridge valve C19 through a ninth pressure regulating valve F9. Decompression is performed after the pressure maintaining of the sliding block: the thirteenth cartridge valve C13 is closed by the power failure of the ninth electromagnetic directional valve YV9, the eighteenth cartridge valve C18 is closed by the power failure of the fourteenth electromagnetic directional ball valve YV14, the nineteenth cartridge valve C19 is closed by the power failure of the fifteenth electromagnetic directional valve YV15, and the rest electromagnetic directional valves are all kept in a power failure state. Slider return stroke: the tenth electromagnetic directional valve YV10 is powered to close the fourteenth cartridge valve C14, and the pressure of the outlet pipeline G2 of the main oil pump is built; the eleventh electromagnetic directional valve YV11 is powered on, and the fifteenth cartridge valve C15 is opened; the pressure oil of the main oil pump outlet pipeline G2 passes through the fifteenth cartridge valve C15 and pushes the eighteenth cartridge valve C18 to enter the lower cavity of the slider main cylinder 1 a; the return force is controlled by a tenth pressure regulating valve F10; the charging valve control oil pipe G3 builds pressure, the charging valves CF1 are opened, and the oil in the upper cavity of the slider main cylinder 1a and the oil in the slider plunger cylinder 1b return to the oil tank through the charging valves CF 1.

As a further improvement of the invention, the upper cavity of the hydraulic cushion piston cylinder 2a is connected with the outlet of the fifth one-way valve D5, and the inlet of the fifth one-way valve D5 is connected with the oil tank; the outlet of the servo pump B1 is connected with the inlet of a tenth cartridge valve C10, the hydraulic control port of the tenth cartridge valve C10 is connected with the B port of a sixth electromagnetic directional valve YV6, the outlet of the tenth cartridge valve C10 and the T port of the sixth electromagnetic directional valve YV6 are connected with an oil tank, and the sixth electromagnetic directional valve YV6 is a two-position four-way electromagnetic directional valve. When the hydraulic cushion is down, the fifth one-way valve D5 is sucked open, and the oil in the oil tank enters the upper cavity of the hydraulic cushion piston cylinder 2a through the fifth one-way valve D5. When the sixth electromagnetic reversing valve YV6 is powered off, the tenth cartridge valve C10 is opened, and oil at the outlet of the servo pump B1 circulates through an oil return tank of the tenth cartridge valve C10; when the hydraulic cushion is quickly jacked, the sixth electromagnetic directional valve YV6 is electrified, the tenth cartridge valve C10 is closed, the pressure is built up in the outlet oil way of the servo pump B1, the hydraulic control port of the tenth cartridge valve C10 is controlled by the sixth pressure regulating valve F6, and the operation safety of the servo pump B1 is ensured. When the hydraulic cushion stretches and the cylinders are forced to retract, the sixth electromagnetic directional valve YV6 returns to the power-off state, and the tenth cartridge valve C10 is opened.

As a further improvement of the invention, a servo motor M1 and each electromagnetic directional valve of a servo pump B1 are controlled by a control system, the control system comprises a PLC controller and a servo controller SDR, a pressure switch H1 is connected to a pipeline between an accumulator AC and an outlet of an eleventh cartridge valve C11, a signal output end of a hydraulic cushion displacement sensor S1 is connected to a hydraulic cushion displacement signal input end IN1 of the PLC controller, a high-voltage closed normally open contact H1-1 of the pressure switch H1 is connected IN series between a high-voltage signal input end 000 port of the PLC controller and a direct-current power supply negative pole VDC-, and a low-voltage open normally closed contact H1-2 of the pressure switch H1 is connected IN series between a low-voltage signal input end 001 port of the PLC controller and the direct-current power supply negative pole VDC-; the 002 port of the high-low voltage switching signal output end of the PLC is connected with the MC of the servo pump switching signal input end of the SDR; the flow increasing signal output end OUT1 of the PLC is connected with the flow increasing signal input end AI3 of the servo controller SDR, and the flow decreasing signal output end COM1 of the PLC is connected with the flow decreasing signal input end FAC3 of the servo controller SDR; the pressure increasing signal output end OUT2 of the PLC is connected with the pressure increasing signal input end AI2 of the servo controller SDR, and the pressure decreasing signal output end COM2 of the PLC is connected with the pressure decreasing signal input end FAC2 of the servo controller SDR; the servo enabling button SB1 is connected between a start signal input end DI3 of the servo controller SDR and the common end COM; the pump port pressure sensor P1 for detecting the output pressure of the servo pump B1 is connected to the servo pump pressure signal input AI1 of the servo controller SDR. The servo enable button SB1 is pressed, and the servo controller SDR is put into operation. When the sliding block is fast down, the oil outlet of the rod cavity of the main cylinder 1a of the sliding block pre-charges the energy accumulator AC, after the sliding block is slowly rotated down, the servo pump B1 continues to charge the energy accumulator AC until the high-voltage closed normally open contact H1-1 of the pressure switch H1 is closed, a signal of the energy accumulator AC reaching high voltage is input to a high-voltage signal input end 000 port of the PLC controller, the PLC controller causes the eighth electromagnetic reversing valve YV8 to lose electricity, the eleventh cartridge valve C11 is closed, and the sliding block is ready to enter the working pressure of the sliding block. When the hydraulic cushion 2 is rapidly ejected, the pressure oil stored in the accumulator AC is rapidly replenished into the four hydraulic cushion plunger cylinders 2 b. When the hydraulic cushion slowly pushes up, when the hydraulic cushion displacement sensor S1 detects that the hydraulic cushion 2 rises to a set position or the accumulator AC is lowered to low pressure, the low-pressure disconnection normally-closed contact H1-2 of the pressure switch H1 is disconnected, the PLC controller causes the seventh electromagnetic reversing valve YV7 to lose electricity, the ninth cartridge valve C9 is closed, and the accumulator AC stops supplementing oil to the four hydraulic cushion plunger cylinders 2 b; the second electromagnetic reversing valve YV2 is electrified to enable the second cartridge valve C2 to be opened, and pressure oil output by the servo pump B1 simultaneously enters the hydraulic cushion piston cylinder 2a and the four hydraulic cushion piston cylinders 2B, so that the hydraulic cushion 2 is ejected slowly. The servo pump B1 is combined with the hydraulic cushion displacement sensor S1, and accurate control of the ejection position of the hydraulic cushion 2 can be realized through closing operation control, so that the one-time forming rate of parts is improved. The servo pump B1 comprises a low-pressure pump and a high-pressure pump driven by the same servo motor M1, and when the hydraulic cushion is fast-topped and the hydraulic cushion is slow-topped, a high-low pressure switching signal output end 002 port of the PLC controller inputs a low-pressure operation signal of the servo pump B1 into a servo pump switching signal input end MC of the servo controller SDR, so that the servo motor M1 drives the low-pressure pump to operate. When each cylinder of the hydraulic cushion retreats, the high-low pressure switching signal output end 002 port of the PLC controller inputs the high-pressure operation signal of the servo pump B1 into the servo pump switching signal input end MC of the servo controller SDR, so that the servo motor M1 drives the high-pressure pump to operate. When the flow rate increase signal output terminal OUT1 of the PLC controller transmits a flow rate increase analog signal to the flow rate increase signal input terminal AI3 of the servo controller SDR, the servo motor M1 controls the servo pump B1 to increase the flow rate output. When the flow rate reduction signal output terminal COM1 of the PLC controller transmits a flow rate reduction analog signal to the flow rate reduction signal input terminal FAC3 of the servo controller SDR, the servo motor M1 controls the servo pump B1 to reduce the flow rate output. When the pressure increase signal output terminal OUT2 of the PLC controller transmits a pressure increase analog signal to the pressure increase signal input terminal AI2 of the servo controller SDR, the servo motor M1 controls the servo pump B1 to increase the oil pressure. When the pressure-decrease signal output terminal COM2 of the PLC controller transmits a pressure-decrease analog signal to the pressure-decrease signal input terminal FAC2 of the servo controller SDR, the servo motor M1 controls the servo pump B1 to decrease the oil pressure.

As a further development of the invention, each working cycle of the hydraulic machine comprises the following actions in sequence: quick down of slider one-level: the thirteenth cartridge valve C13 is opened, and oil is filled into the upper cavity of the slider main cylinder 1a and the slider plunger cylinder 1b; the eleventh cartridge valve C11, the sixteenth cartridge valve C16, the seventeenth cartridge valve C17, the eighteenth cartridge valve C18 and the twentieth cartridge valve C20 are opened, and the oil outlet of the rod cavity of the slider main cylinder 1a pre-charges the accumulator AC; second grade of slider is fast down: the sixteenth cartridge valve C16 is closed when the twelfth electromagnetic directional valve YV12 is powered off; the sliding block is slowly lowered: the twentieth cartridge valve C20 is closed and the precharge of the accumulator AC is ended; continuously charging the accumulator AC by the servo pump B1, and closing the eleventh cartridge valve C11 and the seventeenth cartridge valve C17 after the charging is finished; fourth, slider working pressurization: the supporting force of the lower cavity of the slider main cylinder 1a is controlled by a ninth pressure regulating valve F9; pressure relief is performed after pressure maintaining of the sliding block: the thirteenth cartridge valve C13, the eighteenth cartridge valve C18 and the nineteenth cartridge valve C19 are closed, and all other electromagnetic directional valves are kept in a power-off state; sixth step of slider return stroke: the fourteenth cartridge valve C14 is closed, the fifteenth cartridge valve C15 is opened, and the pressure oil of the main oil pump outlet pipeline G2 enters the lower cavity of the slider main cylinder 1 a; the return force is controlled by a tenth pressure regulating valve F10; the charging valves CF1 are opened, and the oil in the upper cavity of the slider main cylinder 1a and the oil in the slider plunger cylinder 1b pass through the charging valves CF1 and return to the oil tank. According to the hydraulic machine, the accumulator AC is pre-pressurized by utilizing oil discharged from the rod cavity when the sliding block is quickly lowered, so that energy sources can be effectively saved.

As a further development of the invention, each working cycle of the hydraulic machine comprises in turn the following actions: and (3) a hydraulic cushion fast roof: the eleventh cartridge valve C11 and the twentieth cartridge valve C20 are closed, the ninth cartridge valve C9 is opened, and the pressure oil in the accumulator AC is rapidly fed into the four hydraulic cushion plunger cylinders 2b; simultaneously, the first cartridge valve C1 and the third cartridge valve C3 are opened, pressure oil output by the servo pump B1 enters a lower cavity of the hydraulic cushion piston cylinder 2a, and oil in an upper cavity of the hydraulic cushion piston cylinder 2a flows back to an oil tank through a sixth cartridge valve C6; slow top of hydraulic cushion: when the hydraulic cushion 2 rises to the set position, the ninth cartridge valve C9 is closed, and the accumulator AC stops supplementing the four hydraulic cushion plunger cylinders 2b with oil; the second cartridge valve C2 is opened, and the pressure oil output by the servo pump B1 simultaneously enters the hydraulic cushion piston cylinder 2a and the four hydraulic cushion plunger cylinders 2B; the cylinders of the hydraulic cushion retract: the third cartridge valve C3 is closed, the fourth cartridge valve C4 and the seventh cartridge valve C7 are opened, and the oil in the lower cavity of the hydraulic cushion piston cylinder 2a and the oil in the hydraulic cushion plunger cylinder 2b return the oil tank; the hydraulic cushion is stretched, and the cylinders are forced to retract: the third electromagnetic directional valve returns to the middle position, the seventh cartridge valve C7 is closed, the lower cavity of the hydraulic cushion piston cylinder 2a and the oil in the hydraulic cushion piston cylinder 2b return to the oil tank, and the stretching force is controlled by the third pressure regulating valve F3. When the hydraulic cushion is rapidly ejected, the energy accumulator AC is utilized to rapidly supplement oil to the four hydraulic cushion plunger cylinders 2b, and the phenomenon of falling and stopping when the rapid ejection is changed to the slow ejection is eliminated, so that the whole ejection movement realizes stable transition.

Drawings

The invention will now be described in further detail with reference to the drawings and the detailed description, which are provided for reference and illustration only and are not intended to limit the invention.

Fig. 1 is a hydraulic system diagram of an energy-efficient hydraulic machine according to the invention.

Fig. 2 is an enlarged view of the hydraulic cushion system of fig. 1.

FIG. 3 is an enlarged view of the slider system of FIG. 1.

Fig. 4 is an electrical control schematic diagram of the energy-saving hydraulic machine of the present invention.

In the figure: 1. a slide block; 1a, a slider main cylinder; 1b, a sliding block plunger cylinder; 2. a hydraulic cushion; 2a, a hydraulic cushion piston cylinder; 2b, a hydraulic cushion plunger cylinder; B1. a servo pump; the method comprises the steps of M1, a servo motor; ac, accumulator; C1. a third cartridge valve; C2. a second cartridge valve; C3. a third cartridge valve; C4. a fourth cartridge valve; C5. a fifth cartridge valve; C6. a sixth cartridge valve; C7. a seventh cartridge valve; C8. an eighth cartridge valve; C9. a ninth cartridge valve; C10. a tenth cartridge valve; C11. an eleventh cartridge valve; C12. a twelfth cartridge valve; C13. a thirteenth cartridge valve; C14. a fourteenth cartridge valve; C15. a fifteenth cartridge valve; C16. a sixteenth cartridge valve; C17. seventeenth cartridge valve; C18. an eighteenth cartridge valve; C19. nineteenth cartridge valve; C20. a twentieth cartridge valve; CF1, a liquid filling valve; D1. a first one-way valve; D2. a second one-way valve; D3. a third one-way valve; D4. a fourth one-way valve; D5. a fifth check valve; H1. a pressure switch; yv1, a first electromagnetic reversing ball valve; yv2, a second electromagnetic directional valve; YV3, YV4 third electromagnetic directional valve; yv5 fifth electromagnetic directional valve; yv6 sixth electromagnetic directional valve; yv7 seventh electromagnetic directional valve; yv8 eighth electromagnetic directional valve; yv9 ninth electromagnetic directional valve; yv10 tenth electromagnetic directional valve; yv11. Eleventh electromagnetic directional valve; yv12 twelfth electromagnetic directional valve; yv13. Thirteenth electromagnetic directional valve; yv14. Fourteenth electromagnetic reversing ball valve; yv15 fifteenth electromagnetic directional valve; yv16 sixteenth electromagnetic reversing ball valve; G1. a lower cavity oil circuit of the main cylinder of the sliding block; G2. a main oil pump outlet line; G3. a liquid filling valve control oil pipe; SF1, a first shuttle valve; sf2. a second shuttle valve; s1, a hydraulic cushion displacement sensor; F1. a first pressure regulating valve; F2. a second pressure regulating valve; F3. a third pressure regulating valve; F4. a fourth pressure regulating valve; F5. a fifth pressure regulating valve; F6. a sixth pressure regulating valve; F7. a seventh pressure regulating valve; F8. an eighth pressure regulating valve; F9. a ninth pressure regulating valve; F10. a tenth pressure regulating valve; F11. an eleventh pressure regulating valve; SDR, servo controller; pg, encoder; SB1, servo enabling button; EM1, a filter; and R, braking resistance.

Detailed Description

As shown in fig. 1 to 3, the energy-saving hydraulic press of the invention comprises a slide block 1 and a hydraulic cushion 2, wherein the top center of the slide block 1 is connected with the lower end of a slide block plunger cylinder 1b, the left side and the right side of the slide block plunger cylinder 1b are symmetrically provided with a slide block main cylinder 1a, and the lower ends of pistons of the slide block main cylinder 1a are respectively connected with the slide block 1; the center of the bottom of the hydraulic cushion 2 is connected with a hydraulic cushion piston cylinder 2a, four corners of the hydraulic cushion 2 are respectively connected with the top of a hydraulic cushion plunger cylinder 2B, an inlet of a servo pump B1 is connected with an oil tank, an outlet of the servo pump B1 is connected with an inlet of a first one-way valve D1, an outlet of the first one-way valve D1 is respectively connected with a hydraulic cushion control oil path, an inlet of an eleventh cartridge valve C11 and an inlet of a twentieth cartridge valve C20, a hydraulic control port of the eleventh cartridge valve C11 is connected with a P port of an eighth electromagnetic reversing valve YV8, an A port of the eighth electromagnetic reversing valve YV8 is connected with an inlet of the twentieth cartridge valve C20, a B port of the eighth electromagnetic reversing valve YV8 is connected with the oil tank, the eighth electromagnetic reversing valve YV8 is a two-position four-way electromagnetic reversing valve, and an outlet of the eleventh cartridge valve C11 is connected with an accumulator AC; the outlet of the twenty-first cartridge valve C20 is connected with the oil way G1 of the lower cavity of the main cylinder of the sliding block, the hydraulic control port of the twenty-first cartridge valve C20 is connected with the A port of the sixteenth electromagnetic reversing ball valve YV16, the P port of the sixteenth electromagnetic reversing ball valve YV16 is connected with the outlet of the twenty-first cartridge valve C20, the T port of the sixteenth electromagnetic reversing ball valve YV16 is connected with the inlet of the twenty-first cartridge valve C20, the sixteenth electromagnetic reversing ball valve YV16 is a two-position three-way electromagnetic reversing valve, and a seventh pressure regulating valve F7 is arranged between the accumulator AC and the oil tank.

The hydraulic cushion driving cylinder adopts a structure that the hydraulic cushion piston cylinder 2a positioned in the center and the four corners are respectively provided with the hydraulic cushion plunger cylinder 2b, so that the stretching force of the hydraulic cushion 2 is uniformly distributed, and four corners of the stretching force of the hydraulic cushion can be respectively adjustable through the cooperation of a hydraulic system and an electric control system. The structural characteristics of the slider main cylinder 1a and the slider plunger cylinder 1b are fully utilized, when the slider 1 is fast down, the sixteenth electromagnetic reversing ball valve YV16 is powered on, and the twentieth cartridge valve C20 is opened; meanwhile, the eighth electromagnetic directional valve YV8 is powered on, the eleventh cartridge valve C11 is opened, oil discharged from the rod cavity of the slider main cylinder 1a is pre-pressurized to the accumulator AC through the oil way G1 of the lower cavity of the slider main cylinder, the twentieth cartridge valve C20 and the eleventh cartridge valve C11, so that the weight of the slider 1 is balanced, the smooth transition of the fast-down operation of the slider is realized, and the energy conversion is fully realized.

The hydraulic cushion control oil way comprises first to ninth cartridge valves, the bottom of the accumulator AC is connected with the inlet of the ninth cartridge valve C9, the outlet of the ninth cartridge valve C9 is connected with the inlet of the eighth cartridge valve C8, and the outlet of the eighth cartridge valve C8 is connected with the total oil pipe of each hydraulic cushion plunger cylinder 2 b; the eighth cartridge valve C8 is provided with an opening adjusting handle, the hydraulic control port of the ninth cartridge valve C9 is connected with the A port of the seventh electromagnetic directional valve YV7, the seventh electromagnetic directional valve YV7 is a two-position four-way electromagnetic directional valve, the P port of the seventh electromagnetic directional valve YV7 is connected with the inlet of the ninth cartridge valve C9, and the T port of the seventh electromagnetic directional valve YV7 is connected with an oil tank. When the hydraulic cushion 2 is rapidly ejected, the eighth electromagnetic reversing valve YV8 and the sixteenth electromagnetic reversing ball valve YV16 are powered off, and the eleventh cartridge valve C11 and the twentieth cartridge valve C20 are closed; the seventh electromagnetic reversing valve YV7 is electrified, the ninth cartridge valve C9 is opened, the flow is regulated by regulating the opening regulating handle of the eighth cartridge valve C8, and the pressure oil stored in the accumulator AC enters the four hydraulic cushion plunger cylinders 2b through the ninth cartridge valve C9 and the eighth cartridge valve C8, so that the hydraulic cushion plunger cylinders 2b positioned around are rapidly supplemented by the accumulator AC. Because the hydraulic cushion plunger cylinder 2b is subjected to quick oil filling with pressure by the accumulator AC during ejection operation, the phenomenon of falling and stopping during quick ejection to slow ejection is eliminated, and the whole ejection movement realizes stable transition. And by combining the servo pump control technology, the accurate control of pressure and torque can be realized, and the energy is effectively saved.

The inlets of the third cartridge valve C3 and the fifth cartridge valve C5 are respectively connected with the outlet of the first one-way valve D1, the outlet of the third cartridge valve C3 is respectively connected with the inlets of the first cartridge valve C1, the second cartridge valve C2 and the fourth cartridge valve C4, the outlet of the first cartridge valve C1 is connected with the lower cavity of the hydraulic cushion piston cylinder 2a, and the outlet of the second cartridge valve C2 and the inlet of the seventh cartridge valve C7 are respectively connected with the oil ports of the hydraulic cushion piston cylinder 2 b; the outlet of the fifth cartridge valve C5 is respectively connected with the inlet of the sixth cartridge valve C6 and the upper cavity of the hydraulic cushion piston cylinder 2a, the outlets of the fourth cartridge valve C4, the sixth cartridge valve C6 and the seventh cartridge valve C7 are respectively connected with an oil tank, a hydraulic cushion displacement sensor S1 is installed on one side of the hydraulic cushion 2, a first pressure regulating valve F1 is installed between the outlet of the first cartridge valve C1 and the oil tank, and a second pressure regulating valve F2 is installed between the outlet of the second cartridge valve C2 and the oil tank.

The hydraulic control port of the first cartridge valve C1 is connected with the A port of the first electromagnetic reversing ball valve YV1, the first electromagnetic reversing ball valve YV1 is a two-position three-way electromagnetic reversing valve, the P port of the first electromagnetic reversing ball valve YV1 is connected with the outlet of the first cartridge valve C1, and the T port of the first electromagnetic reversing ball valve YV1 is connected with an oil tank; the hydraulic control port of the second cartridge valve C2 is connected with the A port of the second electromagnetic directional valve YV2, the second electromagnetic directional valve YV2 is a two-position four-way electromagnetic directional valve, the P port of the second electromagnetic directional valve YV2 is connected with the inlet of the second cartridge valve C2, and the T port of the second electromagnetic directional valve YV2 is connected with an oil tank; the hydraulic control port of the third cartridge valve C3 is connected with the middle outlet of the first shuttle valve SF1, the right inlet of the first shuttle valve SF1 is connected with the outlet of the third cartridge valve C3, the left inlet of the first shuttle valve SF1 is connected with the A port of the third electromagnetic directional valve, the third electromagnetic directional valve is a three-position four-way electromagnetic directional valve with the middle position function of P, and the B port of the third electromagnetic directional valve is connected with the hydraulic control port of the fifth cartridge valve C5; the P port of the third electromagnetic directional valve is connected with the outlet of the fourth cartridge valve C4, the T port of the third electromagnetic directional valve is connected with the outlet of the third one-way valve D3, and the inlet of the third one-way valve D3 is connected with the inlet of the fifth cartridge valve C5; the port B of the third electromagnetic directional valve is connected with the inlet of a second one-way valve D2, the outlet of the second one-way valve D2 is connected with the hydraulic control port of a fourth cartridge valve C4, and the hydraulic control port of the fourth cartridge valve C4 is also connected with an oil tank through a third pressure regulating valve F3; the port A of the third electromagnetic directional valve is also connected with the outlet of a fourth one-way valve D4, the inlet of the fourth one-way valve D4 is connected with the hydraulic control port of a sixth cartridge valve C6, and the hydraulic control port of the sixth cartridge valve C6 is also connected with an oil tank through a fourth pressure regulating valve F4; the hydraulic control port of the seventh cartridge valve C7 is connected with the B port of the fifth electromagnetic directional valve YV5, the fifth electromagnetic directional valve YV5 is a two-position four-way electromagnetic directional valve, the T port of the fifth electromagnetic directional valve YV5 is connected with the outlet of the seventh cartridge valve C7, and the hydraulic control port of the seventh cartridge valve C7 is connected with an oil tank through a fifth pressure regulating valve F5.

The main oil pump outlet pipeline G2 is respectively connected with inlets of a thirteenth cartridge valve C13, a fourteenth cartridge valve C14 and a fifteenth cartridge valve C15, an outlet of the thirteenth cartridge valve C13 is connected with an inlet of a twelfth cartridge valve C12, and an outlet of the twelfth cartridge valve C12 is connected with upper cavities of the slider plunger cylinder 1b and the slider main cylinder 1 a; the outlet of the fifteenth cartridge valve C15 is respectively connected with the inlets of the sixteenth cartridge valve C16, the seventeenth cartridge valve C17, the eighteenth cartridge valve C18 and the nineteenth cartridge valve C19, the outlet of the eighteenth cartridge valve C18 is connected with the oil way G1 of the lower cavity of the main cylinder of the sliding block, the outlets of the fourteenth cartridge valve C14, the sixteenth cartridge valve C16, the seventeenth cartridge valve C17 and the nineteenth cartridge valve C19 are respectively connected with the oil tank, an eighth pressure regulating valve F8 is arranged between the hydraulic control port of the fourteenth cartridge valve C14 and the oil tank, and an eleventh pressure regulating valve F11 is arranged between the outlet of the eighteenth cartridge valve C18 and the oil tank.

The hydraulic control port of the thirteenth cartridge valve C13 is connected with the A port of the ninth electromagnetic directional valve YV9, the P port of the ninth electromagnetic directional valve YV9 is connected with the inlet of the thirteenth cartridge valve C13, and the T port of the ninth electromagnetic directional valve YV9 is connected with the oil tank; the hydraulic control port of the fourteenth cartridge valve C14 is connected with the port B of the tenth electromagnetic directional valve YV 10; the hydraulic control port of the fifteenth cartridge valve C15 is connected with the middle outlet of the second shuttle valve SF2, the left inlet of the second shuttle valve SF2 is connected with the outlet of the fifteenth cartridge valve C15, the right inlet of the second shuttle valve SF2 is connected with the A port of the eleventh electromagnetic directional valve YV11, and the P port of the eleventh electromagnetic directional valve YV11 is connected with the inlet of the fifteenth cartridge valve C15; the hydraulic control port of the sixteenth cartridge valve C16 is connected with the A port of the twelfth electromagnetic directional valve YV12, and the P port of the twelfth electromagnetic directional valve YV12 is connected with the inlet of the sixteenth cartridge valve C16; the hydraulic control port of the seventeenth cartridge valve C17 is connected with the A port of the thirteenth electromagnetic directional valve YV13, and the P port of the thirteenth electromagnetic directional valve YV13 is connected with the inlet of the seventeenth cartridge valve C17; the hydraulic control port of the eighteenth cartridge valve C18 is connected with the A port of the fourteenth electromagnetic reversing ball valve YV14, and the P port of the fourteenth electromagnetic reversing ball valve YV14 is connected with the outlet of the eighteenth cartridge valve C18; the hydraulic control port of the eighteenth cartridge valve C18 is connected with the A port of the fifteenth electromagnetic directional valve YV15, is connected with the P port of the fifteenth electromagnetic directional valve YV15 through a ninth pressure regulating valve F9, and is connected with the B port of the fifteenth electromagnetic directional valve YV15 through a tenth pressure regulating valve F10; the port T of the tenth electromagnetic directional valve YV10, the eleventh electromagnetic directional valve YV11, the twelfth electromagnetic directional valve YV12, the thirteenth electromagnetic directional valve YV13 and the fourteenth electromagnetic directional ball valve YV14 are respectively connected with an oil tank, and the port B of the fifteenth electromagnetic directional valve YV15 is connected with the oil tank; the fourteenth electromagnetic reversing ball valve YV14 is a two-position three-way electromagnetic reversing valve, and the tenth, eleventh, twelfth, thirteenth and fifteenth electromagnetic reversing valves are two-position four-way electromagnetic reversing valves.

The upper cavity of the hydraulic cushion piston cylinder 2a is connected with the outlet of a fifth one-way valve D5, and the inlet of the fifth one-way valve D5 is connected with an oil tank; the outlet of the servo pump B1 is connected with the inlet of a tenth cartridge valve C10, the hydraulic control port of the tenth cartridge valve C10 is connected with the B port of a sixth electromagnetic directional valve YV6, the outlet of the tenth cartridge valve C10 and the T port of the sixth electromagnetic directional valve YV6 are connected with an oil tank, and the sixth electromagnetic directional valve YV6 is a two-position four-way electromagnetic directional valve. When the hydraulic cushion is down, the fifth one-way valve D5 is sucked open, and the oil in the oil tank enters the upper cavity of the hydraulic cushion piston cylinder 2a through the fifth one-way valve D5. When the sixth electromagnetic reversing valve YV6 is powered off, the tenth cartridge valve C10 is opened, and oil at the outlet of the servo pump B1 circulates through an oil return tank of the tenth cartridge valve C10; when the hydraulic cushion is quickly jacked, the sixth electromagnetic directional valve YV6 is electrified, the tenth cartridge valve C10 is closed, the pressure is built up in the outlet oil way of the servo pump B1, the hydraulic control port of the tenth cartridge valve C10 is controlled by the sixth pressure regulating valve F6, and the operation safety of the servo pump B1 is ensured. When the hydraulic cushion stretches and the cylinders are forced to retract, the sixth electromagnetic directional valve YV6 returns to the power-off state, and the tenth cartridge valve C10 is opened.

As shown IN fig. 4, a servo motor M1 and each electromagnetic directional valve of a servo pump B1 are controlled by a control system, the control system comprises a PLC controller and a servo controller SDR, a pressure switch H1 is connected to a pipeline between an accumulator AC and an outlet of an eleventh cartridge valve C11, a signal output end of a hydraulic cushion displacement sensor S1 is connected to a hydraulic cushion displacement signal input end IN1 of the PLC controller, a high-voltage closed normally open contact H1-1 of the pressure switch H1 is connected IN series between a high-voltage signal input end 000 port of the PLC controller and a direct-current power supply negative pole VDC-, and a low-voltage open normally closed contact H1-2 of the pressure switch H1 is connected IN series between a low-voltage signal input end 001 port of the PLC controller and the direct-current power supply negative pole VDC-; the 002 port of the high-low voltage switching signal output end of the PLC is connected with the MC of the servo pump switching signal input end of the servo controller SDR.

The flow increasing signal output end OUT1 of the PLC is connected with the flow increasing signal input end AI3 of the servo controller SDR, and the flow decreasing signal output end COM1 of the PLC is connected with the flow decreasing signal input end FAC3 of the servo controller SDR; the pressure increasing signal output end OUT2 of the PLC is connected with the pressure increasing signal input end AI2 of the servo controller SDR, and the pressure decreasing signal output end COM2 of the PLC is connected with the pressure decreasing signal input end FAC2 of the servo controller SDR.

The servo enabling button SB1 is connected between a start signal input end DI3 of the servo controller SDR and the common end COM; the pump port pressure sensor P1 for detecting the output pressure of the servo pump B1 is connected to the servo pump pressure signal input AI1 of the servo controller SDR.

The servo enable button SB1 is pressed, and the servo controller SDR is put into operation. When the sliding block is fast down, the oil outlet of the rod cavity of the main cylinder 1a of the sliding block pre-charges the energy accumulator AC, after the sliding block is slowly rotated down, the servo pump B1 continues to charge the energy accumulator AC until the high-voltage closed normally open contact H1-1 of the pressure switch H1 is closed, a signal of the energy accumulator AC reaching high voltage is input to a high-voltage signal input end 000 port of the PLC controller, the PLC controller causes the eighth electromagnetic reversing valve YV8 to lose electricity, the eleventh cartridge valve C11 is closed, and the sliding block is ready to enter the working pressure of the sliding block.

When the hydraulic cushion 2 is rapidly ejected, the pressure oil stored in the accumulator AC is rapidly replenished into the four hydraulic cushion plunger cylinders 2 b. When the hydraulic cushion slowly pushes up, when the hydraulic cushion displacement sensor S1 detects that the hydraulic cushion 2 rises to a set position or the accumulator AC is lowered to low pressure, the low-pressure disconnection normally-closed contact H1-2 of the pressure switch H1 is disconnected, the PLC controller causes the seventh electromagnetic reversing valve YV7 to lose electricity, the ninth cartridge valve C9 is closed, and the accumulator AC stops supplementing oil to the four hydraulic cushion plunger cylinders 2 b; the second electromagnetic reversing valve YV2 is electrified to enable the second cartridge valve C2 to be opened, and pressure oil output by the servo pump B1 simultaneously enters the hydraulic cushion piston cylinder 2a and the four hydraulic cushion piston cylinders 2B, so that the hydraulic cushion 2 is ejected slowly. The servo pump B1 is combined with the hydraulic cushion displacement sensor S1, and accurate control of the ejection position of the hydraulic cushion 2 can be realized through closing operation control, so that the one-time forming rate of parts is improved.

The servo pump B1 comprises a low-pressure pump and a high-pressure pump driven by the same servo motor M1, and when the hydraulic cushion is fast-topped and the hydraulic cushion is slow-topped, a high-low pressure switching signal output end 002 port of the PLC controller inputs a low-pressure operation signal of the servo pump B1 into a servo pump switching signal input end MC of the servo controller SDR, so that the servo motor M1 drives the low-pressure pump to operate.

When each cylinder of the hydraulic cushion retreats, the high-low pressure switching signal output end 002 port of the PLC controller inputs the high-pressure operation signal of the servo pump B1 into the servo pump switching signal input end MC of the servo controller SDR, so that the servo motor M1 drives the high-pressure pump to operate.

When the flow rate increase signal output terminal OUT1 of the PLC controller transmits a flow rate increase analog signal to the flow rate increase signal input terminal AI3 of the servo controller SDR, the servo motor M1 controls the servo pump B1 to increase the flow rate output. When the flow rate reduction signal output terminal COM1 of the PLC controller transmits a flow rate reduction analog signal to the flow rate reduction signal input terminal FAC3 of the servo controller SDR, the servo motor M1 controls the servo pump B1 to reduce the flow rate output.

When the pressure increase signal output terminal OUT2 of the PLC controller transmits a pressure increase analog signal to the pressure increase signal input terminal AI2 of the servo controller SDR, the servo motor M1 controls the servo pump B1 to increase the oil pressure. When the pressure-decrease signal output terminal COM2 of the PLC controller transmits a pressure-decrease analog signal to the pressure-decrease signal input terminal FAC2 of the servo controller SDR, the servo motor M1 controls the servo pump B1 to decrease the oil pressure.

The alarm signal input terminal 104 of the PLC controller is connected to the alarm signal output terminal DO3 of the servo controller SDR. When the servo controller SDR detects a fault, an alarm signal is sent to the alarm signal input end 104 of the PLC controller, and the operation is stopped.

The alternating current power supply is connected to the power end of the servo controller SDR through a filter EM1, a brake resistor R is connected to the X4 port of the servo controller SDR, an encoder PG of the servo motor is connected to the X3 port of the servo controller SDR, the PLC controller adopts an ohm-dragon CP1H-XA40DR-A type, and the servo controller SDR adopts a NAS 4E45/81X type servo controller of Guilin star science and technology Co.

Each working cycle of the hydraulic machine comprises the following actions in sequence: quick down of slider one-level: the thirteenth cartridge valve C13 is opened by powering the ninth electromagnetic directional valve YV9, and oil is fed into the upper cavity of the slider main cylinder 1a and the slider plunger cylinder 1b through the thirteenth cartridge valve C13 and the twelfth cartridge valve C12; the twelfth electromagnetic directional valve YV12 is powered to enable the sixteenth cartridge valve C16 to be opened, the thirteenth electromagnetic directional valve YV13 is powered to enable the seventeenth cartridge valve C17 to be opened, and the fourteenth electromagnetic directional ball valve YV14 is powered to enable the eighteenth cartridge valve C18 to be opened; the fifteenth electromagnetic directional valve YV15 is powered to enable the nineteenth cartridge valve C19 to obtain the support of the ninth pressure regulating valve F9; the sixteenth electromagnetic reversing ball valve YV16 is powered to enable the twentieth cartridge valve C20 to be opened, the eighth electromagnetic reversing valve YV8 is powered to enable the eleventh cartridge valve C11 to be opened, and oil discharged from the rod cavity of the slider main cylinder 1a is subjected to pre-charging on the accumulator AC through the slider main cylinder lower cavity oil way G1, the twentieth cartridge valve C20 and the eleventh cartridge valve C11.

Second grade of slider is fast down: the rest is kept unchanged, the twelfth electromagnetic reversing valve YV12 is powered off to enable the sixteenth cartridge valve C16 to be closed, and the sliding block is ready to be slowly transited.

The sliding block is slowly lowered: the rest is kept unchanged, the sixteenth electromagnetic reversing ball valve YV16 is powered off to enable the twentieth cartridge valve C20 to be closed, and the pre-charging of the accumulator AC by the oil way G1 of the lower cavity of the main cylinder of the sliding block is finished; the servo pump B1 continuously charges the accumulator AC through an eleventh cartridge valve C11, after the charging is completed, the eighth electromagnetic directional valve YV8 is powered off, the eleventh cartridge valve C11 is closed, the thirteenth electromagnetic directional valve YV13 is powered off, the seventeenth cartridge valve C17 is closed, and the slide block is ready to be charged for pressurization.

Fourth, slider working pressurization: the supporting force of the lower chamber of the slider master cylinder 1a is controlled by a nineteenth cartridge valve C19 through a ninth pressure regulating valve F9.

Pressure relief is performed after pressure maintaining of the sliding block: the thirteenth cartridge valve C13 is closed by the power failure of the ninth electromagnetic directional valve YV9, the eighteenth cartridge valve C18 is closed by the power failure of the fourteenth electromagnetic directional ball valve YV14, the nineteenth cartridge valve C19 is closed by the power failure of the fifteenth electromagnetic directional valve YV15, and the rest electromagnetic directional valves are all kept in a power failure state.

Sixth step of slider return stroke: the tenth electromagnetic directional valve YV10 is powered to close the fourteenth cartridge valve C14, and the pressure of the outlet pipeline G2 of the main oil pump is built; the eleventh electromagnetic directional valve YV11 is powered on, and the fifteenth cartridge valve C15 is opened; the pressure oil of the main oil pump outlet pipeline G2 passes through the fifteenth cartridge valve C15 and pushes the eighteenth cartridge valve C18 to enter the lower cavity of the slider main cylinder 1 a; the return force is controlled by a tenth pressure regulating valve F10; the charging valve control oil pipe G3 builds pressure, the charging valves CF1 are opened, and the oil in the upper cavity of the slider main cylinder 1a and the oil in the slider plunger cylinder 1b return to the oil tank through the charging valves CF 1.

And (3) a hydraulic cushion fast roof: the eighth electromagnetic reversing valve YV8 and the sixteenth electromagnetic reversing ball valve YV16 are powered off, and the eleventh cartridge valve C11 and the twentieth cartridge valve C20 are closed; the seventh electromagnetic reversing valve YV7 is electrified, the ninth cartridge valve C9 is opened, the flow is regulated by regulating the opening regulating handle of the eighth cartridge valve C8, and the pressure oil stored in the accumulator AC enters the four hydraulic cushion plunger cylinders 2b through the ninth cartridge valve C9 and the eighth cartridge valve C8, so that the hydraulic cushion plunger cylinders 2b positioned around are rapidly supplemented by the accumulator AC.

Meanwhile, the first electromagnetic reversing ball valve YV1 is powered on, and the first cartridge valve C1 is opened; the left electromagnet YV4 of the third electromagnetic reversing valve is electrified, and the third cartridge valve C3 is opened; the pressure oil output by the servo pump B1 sequentially flows through the third cartridge valve C3 and the first cartridge valve C1 to enter the lower cavity of the hydraulic cushion piston cylinder 2a, and the oil in the upper cavity of the hydraulic cushion piston cylinder 2a flows back to the oil tank through the sixth cartridge valve C6.

Slow top of hydraulic cushion: when the hydraulic cushion displacement sensor S1 detects that the hydraulic cushion 2 rises to the set position, the seventh electromagnetic reversing valve YV7 is powered off to close the ninth cartridge valve C9, and the accumulator AC stops supplementing oil to the four hydraulic cushion plunger cylinders 2 b; the second electromagnetic reversing valve YV2 is electrified to enable the second cartridge valve C2 to be opened, pressure oil output by the servo pump B1 simultaneously enters the hydraulic cushion piston cylinder 2a and the four hydraulic cushion piston cylinders 2B, the hydraulic cushion 2 is slowly ejected, and ejection control of the hydraulic cushion 2 can be realized by adopting the small-displacement servo pump B1. The servo pump B1 is combined with the hydraulic cushion displacement sensor S1, and accurate control of the ejection position of the hydraulic cushion 2 can be realized through closing operation control, so that the one-time forming rate of parts is improved.

The cylinders of the hydraulic cushion retract: the first electromagnetic reversing ball valve YV1 and the second electromagnetic reversing valve YV2 are kept powered, so that the first cartridge valve C1 and the second cartridge valve C2 are kept open; the right electromagnet YV3 of the third electromagnetic reversing valve is electrified to close the third cartridge valve C3; the fourth cartridge valve C4 is opened due to pressure relief of the hydraulic control port, and oil in the lower cavity of the hydraulic cushion piston cylinder 2a returns to the oil tank through the first cartridge valve C1 and the fourth cartridge valve C4; meanwhile, the seventh cartridge valve C7 is opened by the power supply of the fifth electromagnetic directional valve YV5, and oil in the hydraulic cushion plunger cylinder 2b returns to the oil tank through the second cartridge valve C2, the fourth cartridge valve C4 and the seventh cartridge valve C7.

The hydraulic cushion is stretched, and the cylinders are forced to retract: the first electromagnetic reversing ball valve YV1 and the second electromagnetic reversing valve YV2 are kept powered, so that the first cartridge valve C1 and the second cartridge valve C2 are kept open; the right electromagnet YV3 is powered off to enable the third electromagnetic reversing valve to return to the middle position, and the fourth cartridge valve C4 is kept open; the fifth electromagnetic reversing valve YV5 is powered off to enable the seventh cartridge valve C7 to be closed, and oil in the lower cavity of the hydraulic cushion piston cylinder 2a returns to the oil tank through the first cartridge valve C1 and the fourth cartridge valve C4; the oil in the hydraulic cushion plunger cylinder 2b passes through the second cartridge valve C2 and the fourth cartridge valve C4 to return to the oil tank, and the stretching force is controlled by the third pressure regulating valve F3 of the fourth cartridge valve C4.

The foregoing description is only of a preferred embodiment of the invention and is not intended to limit the scope of the invention. In addition to the embodiments described above, other embodiments of the invention are possible. All technical schemes formed by equivalent substitution or equivalent transformation fall within the protection scope of the invention. The technical features of the present invention that are not described may be implemented by or using the prior art, and are not described herein.

Claims

1. The energy-saving hydraulic press comprises a sliding block (1) and a hydraulic cushion (2), wherein the top center of the sliding block (1) is connected to the lower end of a sliding block plunger cylinder (1 b), the left side and the right side of the sliding block plunger cylinder (1 b) are symmetrically provided with a sliding block main cylinder (1 a), and the lower ends of pistons of the sliding block main cylinder (1 a) are respectively connected with the sliding block (1); the bottom center of hydraulic cushion (2) is connected with hydraulic cushion piston cylinder (2 a), its characterized in that: four corners of the hydraulic cushion (2) are respectively connected with the top of a hydraulic cushion plunger cylinder (2B), an inlet of a servo pump (B1) is connected with an oil tank, an outlet of the servo pump (B1) is connected with an inlet of a first one-way valve (D1), an outlet of the first one-way valve (D1) is respectively connected with a hydraulic cushion control oil way, an inlet of an eleventh cartridge valve (C11) and an inlet of a twentieth cartridge valve (C20), a hydraulic control port of the eleventh cartridge valve (C11) is connected with a P port of an eighth electromagnetic reversing valve (YV 8), an A port of the eighth electromagnetic reversing valve (YV 8) is connected with an inlet of the twentieth cartridge valve (C20), an B port of the eighth electromagnetic reversing valve (YV 8) is a two-position four-way electromagnetic reversing valve, an outlet of the eleventh cartridge valve (C11) is connected with an Accumulator (AC), and a seventh pressure regulating valve (F7) is arranged between the Accumulator (AC) and the oil tank; the outlet of the twenty-first cartridge valve (C20) is connected with an oil way (G1) of the lower cavity of the sliding block main cylinder, the hydraulic control port of the twenty-first cartridge valve (C20) is connected with the A port of the sixteenth electromagnetic reversing ball valve (YV 16), the P port of the sixteenth electromagnetic reversing ball valve (YV 16) is connected with the outlet of the twenty-first cartridge valve (C20), the T port of the sixteenth electromagnetic reversing ball valve (YV 16) is connected with the inlet of the twenty-first cartridge valve (C20), and the sixteenth electromagnetic reversing ball valve (YV 16) is a two-position three-way electromagnetic reversing valve;

The hydraulic cushion control oil way comprises first to ninth cartridge valves, the bottom of the energy Accumulator (AC) is connected with the inlet of the ninth cartridge valve (C9), the outlet of the ninth cartridge valve (C9) is connected with the inlet of the eighth cartridge valve (C8), and the outlet of the eighth cartridge valve (C8) is connected with the total oil pipe of each hydraulic cushion plunger cylinder (2 b); the eighth cartridge valve (C8) is provided with an opening adjusting handle, a hydraulic control port of the ninth cartridge valve (C9) is connected with an A port of a seventh electromagnetic directional valve (YV 7), the seventh electromagnetic directional valve (YV 7) is a two-position four-way electromagnetic directional valve, a P port of the seventh electromagnetic directional valve (YV 7) is connected with an inlet of the ninth cartridge valve (C9), and a T port of the seventh electromagnetic directional valve (YV 7) is connected with an oil tank;

the main oil pump outlet pipeline (G2) is respectively connected with inlets of a thirteenth cartridge valve (C13), a fourteenth cartridge valve (C14) and a fifteenth cartridge valve (C15), an outlet of the thirteenth cartridge valve (C13) is connected with an inlet of a twelfth cartridge valve (C12), and an outlet of the twelfth cartridge valve (C12) is connected with upper cavities of the sliding block plunger cylinder (1 b) and the sliding block main cylinder (1 a); the outlet of the fifteenth cartridge valve (C15) is respectively connected with the inlets of the sixteenth cartridge valve (C16), the seventeenth cartridge valve (C17), the eighteenth cartridge valve (C18) and the nineteenth cartridge valve (C19), the outlet of the eighteenth cartridge valve (C18) is connected with the lower cavity oil way (G1) of the main cylinder of the sliding block, and the outlets of the fourteenth cartridge valve (C14), the sixteenth cartridge valve (C16), the seventeenth cartridge valve (C17) and the nineteenth cartridge valve (C19) are respectively connected with the oil tank.

2. The energy efficient hydraulic machine as defined in claim 1, wherein: the inlet of the third cartridge valve (C3) is connected with the outlet of the first check valve (D1) respectively, the outlet of the third cartridge valve (C3) is connected with the inlets of the first cartridge valve (C1), the second cartridge valve (C2) and the fourth cartridge valve (C4) respectively, the outlet of the first cartridge valve (C1) is connected with the lower cavity of the hydraulic cushion piston cylinder (2 a), and the outlet of the second cartridge valve (C2) and the inlet of the seventh cartridge valve (C7) are connected with the oil port of the hydraulic cushion piston cylinder (2 b) respectively; the outlet of the fifth cartridge valve (C5) is respectively connected with the inlet of the sixth cartridge valve (C6) and the upper cavity of the hydraulic cushion piston cylinder (2 a), the outlets of the fourth cartridge valve (C4), the sixth cartridge valve (C6) and the seventh cartridge valve (C7) are respectively connected with the oil tank, and a hydraulic cushion displacement sensor (S1) is arranged on one side of the hydraulic cushion (2).

3. The energy efficient hydraulic machine as defined in claim 2, wherein: the hydraulic control port of the first cartridge valve (C1) is connected with the A port of the first electromagnetic reversing ball valve (YV 1), the first electromagnetic reversing ball valve (YV 1) is a two-position three-way electromagnetic reversing valve, the P port of the first electromagnetic reversing ball valve (YV 1) is connected with the outlet of the first cartridge valve (C1), and the T port of the first electromagnetic reversing ball valve (YV 1) is connected with the oil tank; the hydraulic control port of the second cartridge valve (C2) is connected with the A port of the second electromagnetic directional valve (YV 2), the second electromagnetic directional valve (YV 2) is a two-position four-way electromagnetic directional valve, the P port of the second electromagnetic directional valve (YV 2) is connected with the inlet of the second cartridge valve (C2), and the T port of the second electromagnetic directional valve (YV 2) is connected with the oil tank; the hydraulic control port of the third cartridge valve (C3) is connected with the middle outlet of the first shuttle valve (SF 1), the right-end inlet of the first shuttle valve (SF 1) is connected with the outlet of the third cartridge valve (C3), the left-end inlet of the first shuttle valve (SF 1) is connected with the A port of the third electromagnetic directional valve, the third electromagnetic directional valve is a three-position four-way electromagnetic directional valve with the middle position function of P, and the B port of the third electromagnetic directional valve is connected with the hydraulic control port of the fifth cartridge valve (C5); the P port of the third electromagnetic directional valve is connected with the outlet of the fourth cartridge valve (C4), the T port of the third electromagnetic directional valve is connected with the outlet of the third one-way valve (D3), and the inlet of the third one-way valve (D3) is connected with the inlet of the fifth cartridge valve (C5); the port B of the third electromagnetic directional valve is connected with the inlet of a second one-way valve (D2), the outlet of the second one-way valve (D2) is connected with the hydraulic control port of a fourth cartridge valve (C4), and the hydraulic control port of the fourth cartridge valve (C4) is also connected with the oil tank through a third pressure regulating valve (F3); the port A of the third electromagnetic directional valve is also connected with the outlet of a fourth one-way valve (D4), the inlet of the fourth one-way valve (D4) is connected with the hydraulic control port of a sixth cartridge valve (C6), and the hydraulic control port of the sixth cartridge valve (C6) is also connected with the oil tank through a fourth pressure regulating valve (F4); the hydraulic control port of the seventh cartridge valve (C7) is connected with the B port of the fifth electromagnetic directional valve (YV 5), the fifth electromagnetic directional valve (YV 5) is a two-position four-way electromagnetic directional valve, and the T port of the fifth electromagnetic directional valve (YV 5) is connected with the outlet of the seventh cartridge valve (C7).

4. The energy efficient hydraulic machine as defined in claim 1, wherein: the hydraulic control port of the thirteenth cartridge valve (C13) is connected with the A port of the ninth electromagnetic directional valve (YV 9), the P port of the ninth electromagnetic directional valve (YV 9) is connected with the inlet of the thirteenth cartridge valve (C13), and the T port of the ninth electromagnetic directional valve (YV 9) is connected with the oil tank; the hydraulic control port of the fourteenth cartridge valve (C14) is connected with the port B of the tenth electromagnetic directional valve (YV 10); the hydraulic control port of the fifteenth cartridge valve (C15) is connected with the middle outlet of the second shuttle valve (SF 2), the left inlet of the second shuttle valve (SF 2) is connected with the outlet of the fifteenth cartridge valve (C15), the right inlet of the second shuttle valve (SF 2) is connected with the A port of the eleventh electromagnetic directional valve (YV 11), and the P port of the eleventh electromagnetic directional valve (YV 11) is connected with the inlet of the fifteenth cartridge valve (C15); the hydraulic control port of the sixteenth cartridge valve (C16) is connected with the A port of the twelfth electromagnetic directional valve (YV 12), and the P port of the twelfth electromagnetic directional valve (YV 12) is connected with the inlet of the sixteenth cartridge valve (C16); the hydraulic control port of the seventeenth cartridge valve (C17) is connected with the A port of the thirteenth electromagnetic directional valve (YV 13), and the P port of the thirteenth electromagnetic directional valve (YV 13) is connected with the inlet of the seventeenth cartridge valve (C17); the hydraulic control port of the eighteenth cartridge valve (C18) is connected with the A port of the fourteenth electromagnetic reversing ball valve (YV 14), and the P port of the fourteenth electromagnetic reversing ball valve (YV 14) is connected with the outlet of the eighteenth cartridge valve (C18); the hydraulic control port of the eighteenth cartridge valve (C18) is connected with the A port of the fifteenth electromagnetic directional valve (YV 15), is connected with the P port of the fifteenth electromagnetic directional valve (YV 15) through a ninth pressure regulating valve (F9), and is connected with the B port of the fifteenth electromagnetic directional valve (YV 15) through a tenth pressure regulating valve (F10); the T ports of a tenth electromagnetic directional valve (YV 10), an eleventh electromagnetic directional valve (YV 11), a twelfth electromagnetic directional valve (YV 12), a thirteenth electromagnetic directional valve (YV 13) and a fourteenth electromagnetic directional ball valve (YV 14) are respectively connected with the oil tank, and the B port of the fifteenth electromagnetic directional valve (YV 15) is connected with the oil tank; the fourteenth electromagnetic reversing ball valve (YV 14) is a two-position three-way electromagnetic reversing valve, and the tenth, eleventh, twelfth, thirteenth and fifteenth electromagnetic reversing valves are two-position four-way electromagnetic reversing valves.

5. The energy efficient hydraulic machine as defined in claim 4, wherein: the upper cavity of the hydraulic cushion piston cylinder (2 a) is connected with the outlet of a fifth one-way valve (D5), and the inlet of the fifth one-way valve (D5) is connected with an oil tank; the outlet of the servo pump (B1) is connected with the inlet of a tenth cartridge valve (C10), the hydraulic control port of the tenth cartridge valve (C10) is connected with the B port of a sixth electromagnetic directional valve (YV 6), the outlet of the tenth cartridge valve (C10) and the T port of the sixth electromagnetic directional valve (YV 6) are connected with an oil tank, and the sixth electromagnetic directional valve (YV 6) is a two-position four-way electromagnetic directional valve.

6. The energy efficient hydraulic machine as defined in claim 5, wherein: the servo motor (M1) and each electromagnetic directional valve of the servo pump (B1) are controlled by a control system, the control system comprises a PLC controller and a servo controller (SDR), a pressure switch (H1) is connected to a pipeline between an energy Accumulator (AC) and an eleventh cartridge valve (C11) outlet, a signal output end of a hydraulic pad displacement sensor (S1) is connected to a hydraulic pad displacement signal input end (IN 1) of the PLC controller, a high-voltage closed normally open contact (H1-1) of the pressure switch (H1) is connected IN series between a high-voltage signal input end (000 ports) of the PLC controller and a direct current power supply negative electrode (VDC-) and a low-voltage open normally closed contact (H1-2) of the pressure switch (H1) is connected IN series between a low-voltage signal input end (001 ports) of the PLC controller and the direct current power supply negative electrode (VDC-). The high-low voltage switching signal output end (002 port) of the PLC is connected with the servo pump switching signal input end (MC) of the servo controller (SDR); the flow increasing signal output end (OUT 1) of the PLC is connected with the flow increasing signal input end (AI 3) of the servo controller (SDR), and the flow decreasing signal output end (COM 1) of the PLC is connected with the flow decreasing signal input end (FAC 3) of the servo controller (SDR); the pressure increasing signal output end (OUT 2) of the PLC is connected with the pressure increasing signal input end (AI 2) of the servo controller (SDR), and the pressure reducing signal output end (COM 2) of the PLC is connected with the pressure reducing signal input end (FAC 2) of the servo controller (SDR); the servo enabling button (SB 1) is connected between a start signal input end (DI 3) and a common end (COM) of the servo controller (SDR); a pump port pressure sensor (P1) for detecting the output pressure of the servo pump (B1) is connected with a servo pump pressure signal input end (AI 1) of the servo controller (SDR).

7. The energy efficient hydraulic machine as defined in claim 6, wherein: each working cycle of the hydraulic machine comprises the following actions in turn: quick down of slider one-level: the thirteenth cartridge valve (C13) is opened, and oil is filled into the upper cavity of the slider main cylinder (1 a) and the slider plunger cylinder (1 b); the eleventh cartridge valve (C11), the sixteenth cartridge valve (C16), the seventeenth cartridge valve (C17), the eighteenth cartridge valve (C18) and the twentieth cartridge valve (C20) are opened, and the oil outlet of the rod cavity of the slider main cylinder (1 a) pre-charges the energy Accumulator (AC); second grade of slider is fast down: the sixteenth electromagnetic reversing valve (YV 12) is powered off to close the sixteenth cartridge valve (C16); the sliding block is slowly lowered: the twentieth cartridge valve (C20) is closed and the pre-charging of the Accumulator (AC) is ended; continuously charging the Accumulator (AC) by the servo pump (B1), and closing an eleventh cartridge valve (C11) and a seventeenth cartridge valve (C17) after the charging is finished; fourth, slider working pressurization: the supporting force of the lower cavity of the slider main cylinder (1 a) is controlled by a ninth pressure regulating valve (F9); pressure relief is performed after pressure maintaining of the sliding block: the thirteenth cartridge valve (C13), the eighteenth cartridge valve (C18) and the nineteenth cartridge valve (C19) are closed, and all other electromagnetic directional valves are kept in a power-off state; sixth step of slider return stroke: the fourteenth cartridge valve (C14) is closed, the fifteenth cartridge valve (C15) is opened, and the pressure oil of the main oil pump outlet pipeline (G2) enters the lower cavity of the slider main cylinder (1 a); the return force is controlled by a tenth pressure regulating valve (F10); the charging valves (CF 1) are opened, and oil in the upper cavity of the slider main cylinder (1 a) and the oil in the slider plunger cylinder (1 b) are returned to the oil tank through the charging valves (CF 1).

8. The energy efficient hydraulic machine as defined in claim 7, wherein: each working cycle of the hydraulic machine further comprises the following actions in sequence: and (3) a hydraulic cushion fast roof: the eleventh cartridge valve (C11) and the twentieth cartridge valve (C20) are closed, the ninth cartridge valve (C9) is opened, and the pressure oil in the Accumulator (AC) is rapidly fed into the four hydraulic cushion plunger cylinders (2 b); meanwhile, the first cartridge valve (C1) and the third cartridge valve (C3) are opened, pressure oil output by the servo pump (B1) enters a lower cavity of the hydraulic cushion piston cylinder (2 a), and oil in an upper cavity of the hydraulic cushion piston cylinder (2 a) flows back to an oil tank through the sixth cartridge valve (C6); slow top of hydraulic cushion: when the hydraulic cushion (2) rises to a set position, the ninth cartridge valve (C9) is closed, and the Accumulator (AC) stops supplementing oil to the four hydraulic cushion plunger cylinders (2 b); the second cartridge valve (C2) is opened, and pressure oil output by the servo pump (B1) simultaneously enters the hydraulic cushion piston cylinder (2 a) and the four hydraulic cushion piston cylinders (2B); the cylinders of the hydraulic cushion retract: the third cartridge valve (C3) is closed, the fourth cartridge valve (C4) and the seventh cartridge valve (C7) are opened, and oil in the lower cavity of the hydraulic cushion piston cylinder (2 a) and oil in the hydraulic cushion plunger cylinder (2 b) return to the oil tank; the hydraulic cushion is stretched, and the cylinders are forced to retract: the third electromagnetic reversing valve returns to the middle position, the seventh cartridge valve (C7) is closed, the lower cavity of the hydraulic cushion piston cylinder (2 a) and the oil return tank in the hydraulic cushion piston cylinder (2 b) are connected, and the stretching force is controlled by the third pressure regulating valve (F3).