Differential hydraulic cylinder control system for pile hammer

Abstract

The utility model discloses a differential hydraulic cylinder control system for a pile hammer. A hydraulic power oil source is communicated with a lower cavity of a hydraulic cylinder and a differential cartridge valve working cavity of a 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 a differential control electromagnetic valve, a working oil port A of the differential control electromagnetic valve is communicated with a differential cartridge valve control cavity of the differential cartridge valve, and an oil return port T of the differential control electromagnetic valve leads to an oil tank. The hydraulic power oil source further leads to a pressure oil port P of the oil return control electromagnetic valve, a working oil port A of the oil return control electromagnetic 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 oil return control electromagnetic valve leads to the oil tank. The control system is large in through flow, sensitive in action, safe and reliable, and control over oil pressure and flow is conveniently achieved.

Description

Technical Field

[0001] The utility model relates to 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 for a pile hammer, which not only has a large system flow rate and sensitive action, but also a fast response speed, and is convenient for controlling the oil pressure and flow.

[0005] In order to solve the above technical problems, the differential hydraulic cylinder control system for a pile hammer of the utility model comprises 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.

[0006] The hydraulic power oil source is in communication with the lower chamber of the hydraulic cylinder and the differential cartridge valve working chamber of the differential cartridge valve;

[0007] The upper chamber of the hydraulic cylinder is connected to the differential cartridge valve annular chamber of the differential cartridge valve and the oil return cartridge valve working chamber of the oil return cartridge valve, and the oil return cartridge valve annular chamber of the oil return cartridge valve leads to the oil tank;

[0008] The hydraulic power oil source leads to the pressure oil port P of the differential control solenoid valve, the working oil port A of the differential control solenoid valve is connected to the differential cartridge valve control chamber of the differential cartridge valve, and the oil return port T of the differential control solenoid valve leads to the oil tank;

[0009] The hydraulic power oil source also leads to the pressure oil port P of the return oil control solenoid valve, the working oil port A of the return oil control solenoid 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 return oil control solenoid valve leads to the oil tank.

[0010] 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, and meet the actual needs of the pile hammer to develop in the direction of large-scale and large tonnage. In addition, since the differential control solenoid valve and the differential cartridge valve constitute the differential control unit of the hydraulic cylinder, and the oil return control solenoid valve and the oil return cartridge valve constitute the oil return control unit of the hydraulic cylinder, this dual-unit independent control structure not only avoids the switching interference between the differential hydraulic circuit and the oil return hydraulic circuit, and ensures the accuracy and reliability of the hydraulic cylinder in realizing the lifting and dropping of the hammer, but also through the orderly control of the independent pilot control solenoid valve and the cartridge valve, the response speed is faster, and the accurate control of the system oil direction, pressure and flow can be achieved. Also, due to the use of a differential control unit and an oil return control unit that are independent and orderly controlled, the hammer head can be reversingly adjusted 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.

[0011] 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.

[0012] 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.

[0013] 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 differential control solenoid 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.

[0014] In a preferred embodiment of the utility model, the differential control solenoid valve and the oil return control solenoid valve are both two-position three-way solenoid valves. Alternatively, the differential control solenoid valve and the oil return control solenoid valve are both two-position four-way solenoid valves, which include a pressure oil port P, an oil return port T, a working oil port A, and a working oil port B, wherein the working oil port B is closed, thereby increasing the selectivity of the pilot control solenoid valve.

[0015] In a further embodiment of the utility model, the lower chamber of the hydraulic cylinder is connected to the oil inlet bypass accumulator, and the oil return cartridge valve annular chamber of the oil return cartridge valve, the oil return port T of the differential control solenoid valve and the oil return port T of the oil return control solenoid valve are connected to the oil return bypass accumulator. The oil pressure stability of the hydraulic circuit can be effectively controlled to prevent the vibration of the oil pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The differential hydraulic cylinder control system for a pile hammer of the utility model will be further described below in conjunction with the accompanying drawings and specific implementations.

[0017] Figure 1 This is a schematic diagram of the principle of a differential hydraulic cylinder control system for a pile hammer of the utility model;

[0018] Figure 2 This is a principle diagram of the hammer lifting state of a specific implementation method of the utility model;

[0019] Figure 3 yes Figure 2 Schematic diagram of the hammer drop state of the embodiment shown;

[0020] Figure 4 This is a principle diagram of the hammer lifting state of another specific implementation method of the utility model;

[0021] Figure 5 yes Figure 4 Schematic diagram of the falling hammer state of the embodiment shown.

[0022] In the figure, 1 is a hydraulic cylinder, 2 is a lower chamber of the hydraulic cylinder, 3 is an upper chamber of the hydraulic cylinder, 4 is a hydraulic power oil source, 5 is an oil inlet bypass accumulator, 6 is a safety cartridge valve, 7 is a control chamber of the safety cartridge valve, 8 is an annular chamber of the safety cartridge valve, 9 is a working chamber of the safety cartridge valve, 10 is a differential control solenoid valve, 11 is a differential cartridge valve, 12 is a control chamber of the differential cartridge valve, 13 is an annular chamber of the differential cartridge valve, 14 is a working chamber of the differential cartridge valve, 15 is an oil return control solenoid valve, 16 is an oil return cartridge valve, 17 is an oil return cartridge valve control chamber, 18 is an annular chamber of the oil return cartridge valve, 19 is an oil return cartridge valve working chamber, 20 is an oil return bypass accumulator, and 21 is an oil tank. DETAILED DESCRIPTION

[0023] Figure 1The differential hydraulic cylinder control system for a pile hammer shown in the figure comprises a hydraulic cylinder 1 and a hydraulic power oil source 4. The hydraulic cylinder 1 adopts a double-rod piston structure. The piston slidably supported in the cylinder cavity of the hydraulic cylinder 1 divides the cylinder cavity into a hydraulic cylinder lower cavity 2 and a hydraulic cylinder upper cavity 3. The piston rod diameter on the upper side of the piston is smaller than the piston rod diameter on the lower side of the piston, so as to form a hydraulic differential connection circuit. The extended end of the piston rod on the lower side of the piston is fixedly connected to the hammer head of the pile hammer. The hydraulic power oil source 4 comprises a hydraulic pump and a relief valve for providing pressure oil. The hydraulic power oil source 4 is a basic structure commonly used in hydraulic control systems.

[0024] The hydraulic control system also includes a differential control solenoid valve 10 and an oil return control solenoid valve 15, as well as a differential cartridge valve 11, an oil return cartridge valve 16 and a safety cartridge valve 6. The differential control solenoid valve 10 and the oil return control solenoid valve 15 both include a pressure oil port P, an oil return port T and a working oil port A; the differential control solenoid valve 10 and the oil return control solenoid valve 15 both use a double-coil control solenoid valve, and this type of solenoid valve 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 16 and the safety cartridge valve 6 all use a cartridge structure, which not only has a simple valve core structure and strong versatility, but also has sensitive action and good sealing. The differential cartridge valve 11, the oil return cartridge valve 16 and the safety cartridge valve 6 all include corresponding control chambers, annular chambers and working chambers. The control system also includes an oil inlet bypass accumulator 5 and an oil return bypass accumulator 20. The oil inlet bypass accumulator 5 and the oil return bypass accumulator 20 are bladder accumulators, and other common accumulator structures may also be used.

[0025] The high-pressure oil port of the hydraulic power oil source 4 is connected to the hydraulic cylinder lower chamber 2 of the hydraulic cylinder 1, and the high-pressure oil port of the hydraulic power oil source 4 is also connected to the differential cartridge valve working chamber 14 of the differential cartridge valve 11 through the hydraulic cylinder lower chamber 2. The hydraulic cylinder upper 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 hydraulic cylinder upper chamber 3 is also connected to the oil return cartridge valve working chamber 19 of the oil return cartridge valve 16 through the differential cartridge valve annular chamber 13 of the differential cartridge valve 11, and the oil return cartridge valve annular chamber 18 of the oil return cartridge valve 16 is connected to the oil tank 21. The hydraulic cylinder lower 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 hydraulic cylinder upper chamber 3 is connected to the safety cartridge valve working chamber 9 of the safety cartridge valve 6.

[0026] The differential control solenoid valve 10 and the differential cartridge valve 11 constitute a differential control unit. The working oil port A of the differential control solenoid valve 10 is connected to the differential cartridge valve control chamber 12 of the differential cartridge valve 11; the high-pressure oil port of the hydraulic power oil source 4 and the lower chamber 2 of the hydraulic cylinder, which are connected to each other, are connected to the pressure oil port P of the differential control solenoid valve 10, and the return oil port T of the differential control solenoid valve 10 leads to the oil tank 21.

[0027] The oil return control solenoid valve 15 and the oil return cartridge valve 16 constitute an oil return control unit. The high pressure oil port of the hydraulic power oil source 4 and the lower chamber 2 of the hydraulic cylinder, which are interconnected, are connected to the pressure oil port P of the oil return control solenoid valve 15. The oil return port T of the oil return control solenoid valve 15 leads to the oil tank 21. The working oil port A of the oil return control solenoid valve 15 is connected to the oil return cartridge control chamber 17 of the oil return cartridge valve 16.

[0028] The hydraulic cylinder lower chamber 2 and the high-pressure oil port of the hydraulic power oil source 4 are also connected to the oil inlet bypass accumulator 5. The oil return path of the oil return cartridge valve annular chamber 18 of the oil return cartridge valve 16, the oil return port T of the differential control solenoid valve 10 and the oil return port T of the oil return control solenoid valve 15, which are connected to each other, is connected to the oil return bypass accumulator 20.

[0029] Figure 2 and Figure 3 In the embodiment shown, the hydraulic control system adopts a structure of two differential cartridge valves 11 connected in parallel, which can greatly increase the flow rate of the control circuit to improve the striking energy and striking frequency of the pile hammer. The lower chamber 2 of the hydraulic cylinder is respectively connected to the differential cartridge valve working chambers 14 of the two differential cartridge valves 11, and the working oil port A of the differential control solenoid valve 10 is respectively connected to the differential cartridge valve control chambers 12 of the two differential cartridge valves 11. The differential control solenoid valve 10 and the return oil control solenoid valve 15 are both two-position three-way solenoid valves controlled by double coils.

[0030] like Figure 2 As shown, the differential control solenoid valve 10 is in the right position shown in the figure, and the return oil control solenoid valve 15 is in the left position shown in the figure. At this time, the high-pressure oil of the hydraulic power oil source 4 flows to the differential cartridge valve control chambers 12 of the two differential cartridge valves 11 through the pressure oil port P and the working oil port A of the differential control solenoid valve 10, respectively, and the two differential cartridge valves 11 are in a closed state. The control chamber 17 of the return oil cartridge valve 16 is connected to the oil tank 21 through the working oil port A and the return oil port T of the return oil control solenoid valve 15, and the return oil cartridge valve 16 is in an open state. The high-pressure oil of the hydraulic power oil source 4 is pumped to the hydraulic cylinder lower chamber 2 of the hydraulic cylinder 1, and the oil in the hydraulic cylinder upper chamber 3 flows back to the oil tank 21 through the differential cartridge valve annular chamber 13 of the differential cartridge valve 11, the return oil cartridge valve working chamber 19 of the return oil cartridge valve 16, and the return oil cartridge valve annular chamber 8. The piston and piston rod of the hydraulic cylinder 1 move upward, and the pile hammer is in the hammer lifting working state.

[0031] like Figure 3As shown, the differential control solenoid valve 10 is in the left position as shown in the figure, and the return oil control solenoid valve 15 is in the right position as shown in the figure. At this time, the differential cartridge valve control chambers 12 of the two differential cartridge valves 11 are connected to the oil tank 21 through the working oil port A and the return oil port T of the differential control solenoid valve 10, and the two differential cartridge valves 11 are in an open state, so that the lower chamber 2 of the hydraulic cylinder and the upper chamber 3 of the hydraulic cylinder are connected to each other, forming a differential connection with large flow and fast speed. The high-pressure oil of the hydraulic power oil source 4 is connected to the return oil cartridge valve control chamber 17 of the return oil cartridge valve 16 through the high-pressure oil port P and the working oil port A of the return oil control solenoid valve 15, and the return oil cartridge valve 16 is closed. Since the effective area of ​​the upper chamber 3 of the hydraulic cylinder is larger than the effective area of ​​the lower chamber 2 of the hydraulic cylinder, the acting force is large, the piston and piston rod of the hydraulic cylinder 1 accelerate downward, and the pile hammer is in the drop hammer working state.

[0032] Figure 4 and Figure 5 Another embodiment of the present invention. Figure 2 and Figure 3 The difference between the illustrated implementation manner is that the differential control solenoid valve 10 and the return oil control solenoid valve 15 of this embodiment adopt a two-position four-way solenoid valve controlled by a double coil, and the two-position four-way solenoid valve includes a pressure oil port P, an oil return port T, a working oil port A and a working oil port B, wherein the working oil port B is closed.

[0033] The above embodiments are only used to illustrate the technical solution of the utility model and are not intended to limit it. Although the utility model application is described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents; for example, in a hydraulic control system, one or two differential cartridge valves can be used, and multiple differential cartridge valves can be connected in parallel according to the design requirements of the flow rate; the differential control solenoid valve or the return oil control solenoid valve can use a two-position three-way solenoid valve or a two-position four-way solenoid valve, or a hydraulic or electric control valve with the same function. These do not depart from the spirit and scope of the technical solution of the utility model, and should all be included in the scope of the claims of the utility model.

Claims

1. A differential hydraulic cylinder control system for a pile hammer, 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 (19) of the oil return cartridge valve (16), and the oil return cartridge valve annular chamber (18) of the oil return cartridge valve (16) leads to the oil tank (21); The hydraulic power oil source (4) leads to the pressure oil port P of the differential control solenoid valve (10), the working oil port A of the differential control solenoid valve (10) is connected to the differential cartridge valve control chamber (12) of the differential cartridge valve (11), and the oil return port T of the differential control solenoid valve (10) leads to the oil tank (21); The hydraulic power oil source (4) also leads to the pressure oil port P of the oil return control solenoid valve (15); the working oil port A of the oil return control solenoid valve (15) is connected to the oil return cartridge valve control chamber (17) of the oil return cartridge valve (16); and the oil return port T of the oil return control solenoid valve (15) leads to the oil tank (21).

2. The differential hydraulic cylinder control system for a pile hammer according to claim 1, characterized in that: The upper chamber (3) of the hydraulic cylinder (1) is connected to the oil return cartridge valve working chamber (19) of the oil return cartridge valve (16) through the differential cartridge valve annular chamber (13) of the differential cartridge valve (11).

3. The differential hydraulic cylinder control system for a pile hammer according to claim 1, characterized in that: The lower chamber (2) of the hydraulic cylinder (1) is respectively connected to the safety cartridge valve annular chamber (8) and the 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 (1).

4. The differential hydraulic cylinder control system for a pile hammer 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 (1) is connected to the differential cartridge valve working chamber (14) of each differential cartridge valve (11); and the working oil port A of the differential control solenoid 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 for a pile hammer according to claim 4, characterized in that: The differential control solenoid valve (10) and the oil return control solenoid valve (15) are both two-position three-way solenoid valves.

6. The differential hydraulic cylinder control system for a pile hammer according to claim 4, characterized in that: The differential control solenoid valve (10) and the oil return control solenoid valve (15) are both two-position four-way solenoid valves, which include a pressure oil port P, an oil return port T, a working oil port A and a working oil port B, wherein the working oil port B is closed.

7. The differential hydraulic cylinder control system for a pile hammer according to claim 1, characterized in that: The lower chamber (2) of the hydraulic cylinder (1) is connected to the oil inlet bypass accumulator (5), and the oil return cartridge valve annular chamber (18) of the oil return cartridge valve (16), the oil return port T of the differential control solenoid valve (10) and the oil return port T of the oil return control solenoid valve (15) are all connected to the oil return bypass accumulator (20).

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