Differential hydraulic cylinder control system with cartridge valve

Abstract

The utility model discloses a differential hydraulic cylinder control system with a cartridge valve. A hydraulic power oil source of the differential hydraulic cylinder control system is communicated with a hydraulic cylinder lower cavity and a differential cartridge valve working cavity of the differential cartridge valve; an upper cavity of the hydraulic cylinder is communicated with a differential cartridge valve annular cavity of the differential cartridge valve and an oil return cartridge valve working cavity of the oil return cartridge valve, and an oil return cartridge valve annular cavity of the oil return cartridge valve is communicated with an oil tank. A hydraulic power oil source leads to a pressure oil port P of the electromagnetic control valve, an oil port A of the electromagnetic control valve is communicated with a differential cartridge valve control cavity of the differential cartridge valve, an oil port B of the electromagnetic control valve is communicated with an oil return cartridge valve control cavity of the oil return cartridge valve, and an oil return port T of the electromagnetic control valve leads to an oil tank. The hydraulic cylinder lower cavity is communicated with a safety valve annular cavity and a safety valve control cavity of the safety cartridge valve, and a safety valve working cavity of the safety cartridge valve is communicated with the hydraulic cylinder upper cavity. The control system is large in flow, sensitive in action and high in response speed, and oil pressure and flow control can be achieved conveniently.

Description

Technical Field

[0001] The utility model relates to a hydraulic pile hammer of a pile driving machine, in particular to a hydraulic control system of a differential hydraulic pile hammer with a hydraulic cartridge valve. Background Art

[0002] Hydraulic pile hammer has the characteristics of high pile driving efficiency, no oil fume pollution and low noise and vibration. Its advancedness is widely recognized and hydraulic pile hammer has gradually become the main force in the pile driving market. However, the hydraulic control circuit of existing hydraulic pile hammers often includes a pilot solenoid valve and a multi-stage directional control main valve, which increases the complexity of the hydraulic control circuit, increases the pressure loss of the hydraulic control circuit, and has low action sensitivity, slow response speed, low impact speed and other shortcomings, and the striking energy and speed are limited.

[0003] The applicant applied for and obtained authorization for the "pile hammer hydraulic control system" on December 19, 2018, patent number 2018221314286. The patented technical solution adopts a two-position four-way solenoid valve as a pilot valve, and the main valve adopts a two-position three-way hydraulic control valve. Although this technical solution simplifies the hydraulic control circuit, the flow rate of the main valve is greatly limited, the pressure loss is large, and the action sensitivity is low, which restricts the improvement of the impact energy and frequency of the hydraulic pile hammer, and cannot meet the requirements of the impact and sinking of large foundation piles. Utility Model Content

[0004] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the utility model is to provide a differential hydraulic cylinder control system with a cartridge valve, which not only has a large system flow rate and sensitive action, but also a fast response speed, thereby facilitating the control of oil pressure and flow.

[0005] In order to solve the above technical problems, the utility model provides a differential hydraulic cylinder control system with a cartridge valve, comprising a hydraulic cylinder and a hydraulic power oil source, wherein the hydraulic cylinder is divided into a hydraulic cylinder lower chamber and a hydraulic cylinder upper chamber by a piston; the hydraulic power oil source is connected to the hydraulic cylinder lower chamber and the differential cartridge valve working chamber of the differential cartridge valve; the hydraulic cylinder upper chamber is connected to the differential cartridge valve annular chamber of the differential cartridge valve and the return oil cartridge valve working chamber of the return oil cartridge valve, and the return oil cartridge valve annular chamber of the return oil cartridge valve leads to an oil tank; the hydraulic power oil source leads to the pressure oil port P of the electromagnetic control valve, the working oil port A of the electromagnetic control valve is connected to the differential cartridge valve control chamber of the differential cartridge valve, the working oil port B of the electromagnetic control valve is connected to the return oil cartridge valve control chamber of the return oil cartridge valve, and the return oil port T of the electromagnetic control valve leads to the oil tank.

[0006] After adopting the above technical scheme, since the control circuits for realizing the differential connection of the hydraulic cylinder and the oil return of the hydraulic cylinder both use the cartridge valve as the main valve, the flow rate in the hydraulic circuit is increased, so that the hydraulic control system has a large flow capacity, small pressure loss, short main valve core stroke, sensitive and reliable action; at the same time, the cartridge valve structure also has the characteristics of simple structure, convenient control, stable and reliable operation, ensuring that the pile hammer can achieve large flow, high speed and high striking energy requirements, and meeting the actual needs of the pile hammer to develop in the direction of large-scale and large tonnage. In addition, since the electromagnetic control valve is used as a pilot valve to simultaneously control the main valve core action of the differential cartridge valve and the oil return cartridge valve, not only the control circuit is simpler, which is conducive to the accurate and reliable control of the differential cartridge valve and the oil return cartridge valve, ensuring the accuracy and reliability of the hydraulic cylinder in realizing the lifting and dropping of the hammer, but also the response speed is faster, and the accurate control of the system oil direction, pressure and flow can be achieved. The control circuit composed of the electromagnetic control valve, the differential cartridge valve and the oil return cartridge valve is conducive to realizing the reversing adjustment of the hammer head at any height position, so that the hydraulic control system of the pile hammer can conveniently adjust the hammer lifting height of the pile hammer head, realize light and heavy hitting of the pile hammer, and meet the needs of different piling energies and piling frequencies.

[0007] In a preferred embodiment of the utility model, the upper chamber of the hydraulic cylinder is connected with the working chamber of the oil return cartridge valve of the oil return cartridge valve through the differential cartridge valve annular chamber of the differential cartridge valve, so that the oil circuit layout is more reasonable.

[0008] In a preferred embodiment of the utility model, the lower chamber of the hydraulic cylinder is respectively connected with the safety cartridge valve annular chamber and the safety cartridge valve control chamber of the safety cartridge valve, and the safety cartridge valve working chamber of the safety cartridge valve is connected with the upper chamber of the hydraulic cylinder. When the hydraulic circuit generates abnormally high pressure, the safety and reliability of the hydraulic control system can be ensured.

[0009] In a preferred embodiment of the utility model, the hydraulic control system includes at least two differential cartridge valves; the lower chamber of the hydraulic cylinder is connected to the differential cartridge valve working chamber of each differential cartridge valve, and the working oil port A of the electromagnetic control valve is respectively connected to the differential cartridge valve control chamber of each differential cartridge valve. The differential control unit adopts multiple parallel differential cartridge valves, which can effectively increase the flow rate of the hydraulic control system to improve the striking energy and striking frequency.

[0010] In a preferred embodiment of the utility model, the electromagnetic control valve adopts a two-position four-way electromagnetic valve controlled by double coils, so that one electromagnetic control valve can simultaneously control the orderly operation of two main valves, the differential cartridge valve and the oil return cartridge valve.

[0011] In a further embodiment of the present utility model, the lower chamber of the hydraulic cylinder is communicated with the inlet bypass accumulator, and the return oil cartridge valve annular chamber of the return oil cartridge valve and the return port T port of the electromagnetic control valve are connected to the return oil accumulator, which can effectively control the oil pressure stability of the hydraulic circuit and prevent the vibration of the oil pipeline. Description of the Drawings

[0012] The following further describes the differential hydraulic cylinder control system with cartridge valves of the present utility model in conjunction with the drawings and specific embodiments.

[0013] Figure 1 is a schematic diagram of the principle of the differential hydraulic cylinder control system with cartridge valves of the present utility model;

[0014] Figure 2 is a schematic diagram of the hammer lifting state principle of a specific embodiment of the present utility model;

[0015] Figure 3 is Figure 2 a schematic diagram of the hammer falling state principle of the shown embodiment.

[0016] In the figures, 1 - hydraulic cylinder, 2 - lower chamber of the hydraulic cylinder, 3 - upper chamber of the hydraulic cylinder, 4 - hydraulic power oil source, 5 - inlet bypass accumulator, 6 - safety cartridge valve, 7 - safety cartridge valve control chamber, 8 - safety cartridge valve annular chamber, 9 - safety cartridge valve working chamber, 10 - electromagnetic control valve, 11 - differential cartridge valve, 12 - differential cartridge valve control chamber, 13 - differential cartridge valve annular chamber, 14 - differential cartridge valve working chamber, 15 - return oil cartridge valve, 16 - return oil cartridge valve control chamber, 17 - return oil cartridge valve annular chamber, 18 - return oil cartridge valve working chamber, 19 - return oil bypass accumulator, 20 - oil tank. Specific Embodiment

[0017] Figure 1 The differential hydraulic cylinder control system with cartridge valves shown, the control system includes a hydraulic cylinder 1 and a hydraulic power oil source 4, the hydraulic cylinder 1 adopts a double-rod hydraulic cylinder, a piston slidingly supported in the cylinder cavity of the hydraulic cylinder 1 divides the cylinder cavity into a lower chamber 2 of the hydraulic cylinder and an upper chamber 3 of the hydraulic cylinder, the rod diameter of the piston rod on the upper side of the piston is smaller than the rod diameter of the piston rod on the lower side of the piston, so as to form a hydraulic differential connection circuit. The outer extension end of the piston rod on the lower side of the piston is fixedly connected to the hammer head of the pile driver. The hydraulic power oil source 4 includes a hydraulic pump, an overflow valve, etc. for providing pressure oil, and the hydraulic power oil source 4 is a common basic structure of the hydraulic control system.

[0018] The hydraulic control system further includes an electromagnetic control valve 10, a differential cartridge valve 11, an oil return cartridge valve 15, and a safety cartridge valve 6. The electromagnetic control valve 10 is a two-position four-way solenoid valve controlled by a double coil. The solenoid valve with this structure can reliably ensure the closing or opening of the valve port and has a long service life. The differential cartridge valve 11, the oil return cartridge valve 15, and the safety cartridge valve 6 all adopt the cartridge valve structure. They not only have a simple spool structure and strong versatility, but also are sensitive in action and good in sealing performance. The differential cartridge valve 11, the oil return cartridge valve 15, and the safety cartridge valve 6 all include corresponding control chambers, annular chambers, and working chambers. The hydraulic control system also includes an inlet bypass accumulator 5 and an oil return bypass accumulator 19. The inlet bypass accumulator 5 and the oil return bypass accumulator 19 adopt bladder accumulators, and other common accumulator structures can also be used.

[0019] The high-pressure oil port of the hydraulic power oil source 4 is connected to the lower hydraulic cylinder chamber 2 of the hydraulic cylinder 1, and the high-pressure oil port of the hydraulic power oil source 4 also leads to the differential cartridge valve working chamber 14 of the differential cartridge valve 11 through the lower hydraulic cylinder chamber 2. The upper hydraulic cylinder chamber 3 of the hydraulic cylinder 1 is connected to the differential cartridge valve annular chamber 13 of the differential cartridge valve 11, and the upper hydraulic cylinder chamber 3 also leads to the oil return cartridge valve working chamber 18 of the oil return cartridge valve 15 through the differential cartridge valve annular chamber 13 of the differential cartridge valve 11. The oil return cartridge valve annular chamber 17 of the oil return cartridge valve 15 leads to the fuel tank 20. The lower hydraulic cylinder chamber 2 connected to the high-pressure oil port of the hydraulic power oil source 4 is also connected to the safety cartridge valve annular chamber 8 and the safety cartridge valve control chamber 7 of the safety cartridge valve 6, and the upper hydraulic cylinder chamber 3 is connected to the safety cartridge valve working chamber 9 of the safety cartridge valve 6.

[0020] The hydraulic power oil source 4 leads to the pressure oil port P of the electromagnetic control valve 10. The working oil port A of the electromagnetic control valve 10 is connected to the differential cartridge valve control chamber 12 of the differential cartridge valve 11. The working oil port B of the electromagnetic control valve 10 is connected to the oil return cartridge valve control chamber 16 of the oil return cartridge valve 15. The oil return port T of the electromagnetic control valve 10 leads to the fuel tank 20.

[0021] An inlet bypass accumulator 5 is also connected between the lower hydraulic cylinder chamber 2 and the high-pressure oil port of the hydraulic power oil source 4. The oil return cartridge valve annular chamber 17 of the oil return cartridge valve 15 and the oil return port T of the electromagnetic control valve 10 are connected to the oil return bypass accumulator 20.

[0022] Figure 2 and Figure 3In the illustrated embodiment, the hydraulic control system adopts a structure of two differentially-connected cartridge valves 11 connected in parallel. This structure can greatly increase the flow rate of the control loop to improve the impact energy and impact frequency of the pile hammer. The lower chamber 2 of the hydraulic cylinder is respectively connected to the working chambers 14 of the two differentially-connected cartridge valves 11 of the differentially-connected cartridge valves. The working oil port A of the electromagnetic control valve 10 leads to the control chambers 12 of the two differentially-connected cartridge valves 11 of the differentially-connected cartridge valves respectively. The working oil port B of the electromagnetic control valve 10 is connected to the control chamber 16 of the oil return cartridge valve 15. The electromagnetic control valve 10 is a two-position four-way solenoid valve controlled by a double coil.

[0023] As Figure 2 shown, the electromagnetic control valve 10 is in the right position shown in the figure. At this time, the high-pressure oil from the hydraulic power oil source 4 flows through the pressure oil port P and the working oil port A of the electromagnetic control valve 10 to the control chambers 12 of the two differentially-connected cartridge valves 11 respectively. Both of the two differentially-connected cartridge valves 11 are in the closed state. The control chamber 16 of the oil return cartridge valve 15 leads to the fuel tank 20 through the working oil port B and the return oil port T of the electromagnetic control valve 10. The oil return cartridge valve 15 is in the open state. The high-pressure oil from the hydraulic power oil source 4 is pumped to the lower chamber 2 of the hydraulic cylinder 1. The oil in the upper chamber 3 of the hydraulic cylinder flows back to the fuel tank 20 through the annular chamber 13 of the differentially-connected cartridge valve 11, the working chamber 18 of the oil return cartridge valve 15 and the annular chamber 17 of the oil return cartridge valve. The piston and piston rod of the hydraulic cylinder 1 move upward, and the pile hammer is in the state of lifting the hammer for work.

[0024] As Figure 3 shown, the electromagnetic control valve 10 is in the left position shown in the figure. At this time, the control chambers 12 of the two differentially-connected cartridge valves 11 lead to the fuel tank 20 through the working oil port A and the return oil port T of the differential control solenoid valve 10 respectively. Both of the two differentially-connected cartridge valves 11 are in the open state, so that the lower chamber 2 and the upper chamber 3 of the hydraulic cylinder are connected to each other, forming a differential connection with a large flow rate and high speed. The high-pressure oil from the hydraulic power oil source 4 then leads to the control chamber 16 of the oil return cartridge valve 15 through the high-pressure oil port P and the working oil port B of the electromagnetic control valve 10. The oil return cartridge valve 15 is closed. Since the effective area of the upper chamber 3 of the hydraulic cylinder is larger than that of the lower chamber 2 of the hydraulic cylinder, the acting force is large, and the piston and piston rod of the hydraulic cylinder 1 move downward and accelerate, and the pile hammer is in the state of dropping the hammer for work.

[0025] The above embodiments are only used to illustrate the technical solutions of the present utility model rather than to limit it. Although the present utility model application has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present utility model can be modified or equivalently replaced; for example, in addition to the double-rod hydraulic cylinder, the hydraulic cylinder can also be a hydraulic cylinder with a structure such as a single-rod hydraulic cylinder; in the hydraulic control system, one or two differential cartridge valves can be used, and multiple differential cartridge valves can also be connected in parallel according to the design requirements of the flow rate. These do not depart from the spirit and scope of the technical solutions of the present utility model, and they should all be covered within the scope of the claims of the present utility model.

Claims

1. A differential hydraulic cylinder control system with a cartridge valve, comprising a hydraulic cylinder (1) and a hydraulic power oil source (4), wherein the hydraulic cylinder (1) is divided into a hydraulic cylinder lower chamber (2) and a hydraulic cylinder upper chamber (3) by a piston, and characterized in that: The hydraulic power oil source (4) is connected to the lower chamber (2) of the hydraulic cylinder and the differential cartridge valve working chamber (14) of the differential cartridge valve (11); The upper chamber (3) of the hydraulic cylinder is connected to the differential cartridge valve annular chamber (13) of the differential cartridge valve (11) and the oil return cartridge valve working chamber (18) of the oil return cartridge valve (15), and the oil return cartridge valve annular chamber (17) of the oil return cartridge valve (15) leads to the oil tank (20); The hydraulic power oil source (4) leads to the pressure oil port P of the electromagnetic control valve (10); the working oil port A of the electromagnetic control valve (10) is connected to the differential cartridge valve control chamber (12) of the differential cartridge valve (11); the working oil port B of the electromagnetic control valve (10) is connected to the oil return cartridge valve control chamber (16) of the oil return cartridge valve (15); and the oil return port T of the electromagnetic control valve (10) leads to the oil tank (20).

2. The differential hydraulic cylinder control system with a cartridge valve according to claim 1, characterized in that: The upper chamber (3) of the hydraulic cylinder is connected to the oil return cartridge valve working chamber (18) of the oil return cartridge valve (15) through the differential cartridge valve annular chamber (13) of the differential cartridge valve (11).

3. The differential hydraulic cylinder control system with a cartridge valve according to claim 1, characterized in that: The lower chamber (2) of the hydraulic cylinder is respectively connected to the safety cartridge valve annular chamber (8) and the safety cartridge valve control chamber (7) of the safety cartridge valve (6), and the safety cartridge valve working chamber (9) of the safety cartridge valve (6) is connected to the upper chamber (3) of the hydraulic cylinder.

4. The differential hydraulic cylinder control system with a cartridge valve according to claim 1, 2 or 3, characterized in that: The control system comprises at least two differential cartridge valves (11); the lower chamber (2) of the hydraulic cylinder is connected to the differential cartridge valve working chamber (14) of each differential cartridge valve (11); and the working oil port A of the electromagnetic control valve (10) is respectively connected to the differential cartridge valve control chamber (12) of each differential cartridge valve (11).

5. The differential hydraulic cylinder control system with a cartridge valve according to claim 4, characterized in that: The electromagnetic control valve (10) is a two-position four-way electromagnetic valve controlled by a double coil.

6. The differential hydraulic cylinder control system with a cartridge valve according to claim 1, characterized in that: The lower chamber (2) of the hydraulic cylinder is in communication with the oil inlet bypass accumulator (5), and the oil return cartridge valve annular chamber (17) of the oil return cartridge valve (15) and the oil return port T of the electromagnetic control valve (10) are both in communication with the oil return bypass accumulator (19).

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