High-frequency action hydraulic system of machine tool

Abstract

The high-frequency action hydraulic system of the machine tool comprises a hydraulic station, a high-low pressure valve set and an execution element valve set, the hydraulic station comprises a motor pump set, an oil suction filter, a water cooler, an oil return filter and an oil tank, and the oil suction filter and the water cooler are respectively connected with an inner cavity of the oil tank. The oil suction filter, the motor pump set, the high-low pressure valve set, the oil return filter, the water cooler and the oil tank are sequentially connected to form a loop, and the high-low pressure valve set comprises a one-way valve, a pressure switch, a pressure gauge, an energy accumulator, a manual stop valve, an overflow valve and a zero-leakage on-off valve. The one-way valve, the pressure switch, the pressure gauge, the energy accumulator and the manual stop valve are connected in series and then connected with the overflow valve and the zero-leakage on-off valve in parallel, the one-way valve is connected with the motor pump set in series, the manual stop valve is connected with the oil return filter in series, and the two ends of the manual stop valve are connected with the execution element valve set respectively. The hydraulic station of the hydraulic system can be switched between high pressure and low pressure, response is rapid, heating is reduced, energy efficiency is improved, and stable operation can be achieved during high-pressure operation.

Description

Technical Field

[0001] The utility model belongs to the field of machine tool hydraulic systems, and in particular relates to a high-frequency action hydraulic system of a machine tool. Background Art

[0002] With the explosive growth of new energy vehicles in China, more and more auto parts are made of aluminum alloy. The pure cutting time of aluminum alloy blanks such as die-casting and profiles is short, and the non-processing time, such as fast moving time and tool changing time, actually limits the processing efficiency. The traditional motor plus lead screw drive mode has a fast moving speed of about 20m / min, while the fast moving speed of the linear motor can reach 120m / min, and the dynamic performance is excellent. Therefore, linear motors are increasingly configured on machine tools used to process aluminum alloy parts in the automotive industry.

[0003] The linear motor machine tool itself has an extremely high fast moving speed, and the processing time is usually very short. Therefore, this type of machine tool must have a fast processing cycle and a high frequency of action. However, the high-frequency action of the machine tool puts higher requirements on the hydraulic system of the machine tool, which must respond quickly and run smoothly. The hydraulic station of the general machine tool hydraulic system has two types: normally open and normally closed. For the normally closed hydraulic station, the hydraulic station starts after receiving the action command issued by the hydraulic actuator. After the command ends, the hydraulic station stops. Usually the response is slow. If the action is frequent, the hydraulic station needs to be started and stopped frequently, and the shutdown of the hydraulic station will generally be delayed. The hydraulic station may not be closed for the previous action, and the next action command has arrived. For the normally open hydraulic station, the hydraulic station starts after the machine tool is turned on. The linear motor machine tool has a high action frequency and a large flow, so the hydraulic station will inevitably generate a lot of heat. The linear motor machine tools used in the automotive industry are usually compact in structure, so the heat dissipation problem cannot be solved by increasing the oil tank of the hydraulic station. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a high-frequency action hydraulic system for a machine tool in view of the deficiencies in the prior art, wherein the hydraulic station can switch between high and low pressures, respond quickly, reduce the high-load operation time of the motor pump group, reduce heat generation, improve energy efficiency, and realize smooth operation of the system when operating at high pressure.

[0005] The technical solution adopted by the utility model to solve the above technical problems is: a high-frequency hydraulic system of a machine tool, including a hydraulic station, a high- and low-pressure valve group and an actuator valve group, the hydraulic station includes a motor pump group, an oil suction filter, a water cooler, an oil return filter and an oil tank, the oil suction filter and the water cooler are respectively connected to the inner cavity of the oil tank, the oil suction filter, the motor pump group, the high- and low-pressure valve group, the oil return filter, the water cooler and the oil tank are sequentially connected to form a loop, the high- and low-pressure valve group includes a one-way valve, a pressure switch, a pressure gauge, an accumulator, A manual stop valve, a relief valve and a zero-leakage on-off valve, the one-way valve, the pressure switch, the pressure gauge, the accumulator and the manual stop valve are connected in series in sequence, and then connected in parallel with the relief valve and the zero-leakage on-off valve respectively after being connected in series, the one-way valve is connected in series with the motor pump group, the manual stop valve is connected in series with the return oil filter, the two ends of the manual stop valve are connected to the actuator valve group respectively, the pressure switch is used to set the high pressure value and the low pressure value of the hydraulic system, and the zero-leakage on-off valve is used to switch the high and low pressure operation actions of the hydraulic station.

[0006] The hydraulic system of the utility model is equipped with high and low pressure valve groups, in which accumulators are arranged, and water coolers are arranged at the same time. When working, the hydraulic station is always open, the oil suction filter sucks oil from the oil tank and supplies the high and low pressure valve groups, the system high pressure oil must pass through the high and low pressure valve groups to reach the actuator valve group, and the system return oil passes through the return oil filter and the water cooler and returns to the oil tank.

[0007] The hydraulic station of the hydraulic system of the utility model can switch between high and low pressure through the high and low pressure valve group. When the system is in a low pressure state where the accumulator pressure is insufficient and the system pressure is a low pressure value, the hydraulic station switches to high pressure operation and replenishes oil to the accumulator until the system pressure recovers to the high pressure value; when the accumulator replenishes oil until the system is in a high pressure state, the hydraulic station switches to low pressure operation.

[0008] By switching the high and low pressure of the hydraulic station, the machine tool can respond quickly and run smoothly while ensuring the thermal balance of the hydraulic system.

[0009] The control mode of the hydraulic system of the utility model is flexible. The accumulator can supply oil to the actuator valve group alone, or the accumulator and the motor pump group can supply oil to the actuator valve group at the same time. If the system pressure is used as the basis for the high and low pressure switching of the hydraulic station, then only the accumulator supplies oil to the actuator valve group at this time; if the system pressure is low, or the pressure of a certain actuator is low, or a certain actuator needs to be activated, the hydraulic station can be switched to high-pressure operation. At this time, it is equivalent to the accumulator and the motor pump group supplying oil to the actuator valve group at the same time, which can provide a larger flow rate, and is particularly suitable for the situation where only a few valve groups in the system need a larger flow rate.

[0010] The overflow valve acts as a safety valve. When the system pressure is overloaded, it begins to overflow to protect the system safety.

[0011] When the hydraulic system or accumulator needs to release pressure, the manual stop valve can be directly opened to drain the oil.

[0012] Preferably, the hydraulic station further comprises a liquid level and liquid temperature switch, a refueling port and a liquid level gauge, wherein the liquid level and liquid temperature switch is connected to the inner cavity of the oil tank, the refueling port is arranged on the top of the oil tank, and the liquid level gauge is installed on the inner wall of the oil tank. When the liquid level in the oil tank is low or the liquid temperature is high, the liquid level and liquid temperature switch alarms.

[0013] Preferably, the liquid level gauge is a visual liquid level gauge, and the refueling port is equipped with an air filter.

[0014] Preferably, when the coil on the zero-leakage on-off valve loses power, the zero-leakage on-off valve is turned on, and the oil from the motor pump group flows to the return oil filter through the zero-leakage on-off valve, and the hydraulic station operates at low pressure; when the coil on the zero-leakage on-off valve is energized, the zero-leakage on-off valve is disconnected, and the hydraulic oil flows to the one-way valve, and the hydraulic station operates at high pressure. When the zero-leakage on-off valve is in normal position, that is, when its coil loses power, the oil pumped out by the motor pump group directly returns to the oil tank through the zero-leakage on-off valve, the return oil filter, and the water cooler. The circuit resistance is small, there is no load, and the pressure cannot be established. The hydraulic station operates at low pressure; when the coil on the zero-leakage on-off valve is energized, the zero-leakage on-off valve is disconnected, and the hydraulic oil flows to the one-way valve and flows into the accumulator and the actuator valve group. There is a load in the circuit, and the hydraulic station operates at high pressure.

[0015] Preferably, the pressure switch has at least two alarm points.

[0016] Compared with the prior art, the utility model has the following advantages:

[0017] 1) The hydraulic station of the hydraulic system of the utility model can switch between high and low pressure, respond quickly, reduce the high-load operation time of the motor pump group, reduce heat generation, improve energy efficiency, and realize stable operation of the system when running at high pressure;

[0018] 2) The hydraulic system of the utility model reduces heat generation while realizing high and low pressure switching of the hydraulic station, and is equipped with a water cooler, which can make the oil tank design smaller and facilitate the design of the whole machine tool;

[0019] 3) The control mode of the hydraulic system of the utility model is flexible. The accumulator can supply oil to the actuator valve group alone, or the accumulator and the motor pump group can supply oil to the actuator valve group at the same time. According to different situations, the hydraulic station can be switched to high-pressure operation, and the accumulator and the motor pump group can supply oil to the actuator valve group at the same time, thereby providing a larger flow rate. It is particularly suitable for situations where only individual valve groups in the system require a larger flow rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the high-frequency action hydraulic system of the machine tool in the embodiment;

[0021] Figure 1 The specific reference numerals are as follows:

[0022] 1-Hydraulic station, 11-motor pump group, 12-oil suction filter, 13-liquid level and temperature switch, 14-water cooler, 15-return oil filter, 16-fuel filling port, 17-liquid level gauge, 18-fuel tank, 19-air filter, 2-high and low pressure valve group, 21-zero leakage on-off valve, 22-accumulator, 23-pressure switch, 24-relief valve, 25-check valve, 26-manual stop valve, 27-pressure gauge, 3-actuator valve group. DETAILED DESCRIPTION

[0023] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0024] The high-frequency hydraulic system of the machine tool of the embodiment, such as Figure 1 As shown, it includes a hydraulic station 1, a high-low pressure valve group 2 and an actuator valve group 3. The hydraulic station 1 includes a motor pump group 11, an oil suction filter 12, a liquid level and temperature switch 13, a water cooler 14, an oil return filter 15, a refueling port 16, a liquid level gauge 17 and an oil tank 18. The oil suction filter 12, the liquid level and temperature switch 13 and the water cooler 14 are respectively connected to the inner cavity of the oil tank 18. The oil suction filter 12, the motor pump group 11, the high-low pressure valve group 2, the oil return filter 15, the water cooler 14 and the oil tank 18 are sequentially connected to form a loop. The high-low pressure valve group 2 includes a one-way valve 25, a pressure switch 23, a pressure gauge 27, an accumulator 22, a manual cut-off valve 28, and a pressure switch 29. The valve 26, the relief valve 24 and the zero leakage on-off valve 21, the one-way valve 25, the pressure switch 23, the pressure gauge 27, the accumulator 22 and the manual stop valve 26 are connected in series in sequence, and then connected in parallel with the relief valve 24 and the zero leakage on-off valve 21 respectively after being connected in series. The one-way valve 25 is connected in series with the motor pump group 11, the manual stop valve 26 is connected in series with the return oil filter 15, and both ends of the manual stop valve 26 are connected to the actuator valve group 3 respectively. The pressure switch 23 has at least two alarm points SP1 and SP2. The pressure switch 23 is used to set the high pressure value and low pressure value of the hydraulic system, and the zero leakage on-off valve 21 is used to switch the high and low pressure operation actions of the hydraulic station 1.

[0025] In this embodiment, the refueling port 16 is disposed at the top of the fuel tank 18 , the refueling port 16 is equipped with an air filter 19 , and the liquid level gauge 17 is a visual liquid level gauge 17 , which is installed on the inner wall of the fuel tank 18 .

[0026] In this embodiment, when the coil YV1 on the zero-leakage on-off valve 21 loses power, the zero-leakage on-off valve 21 is turned on, and the oil from the motor pump group 11 flows to the return oil filter 15 through the zero-leakage on-off valve 21, and the hydraulic station operates at low pressure; when the coil YV1 on the zero-leakage on-off valve 21 is energized, the zero-leakage on-off valve 21 is disconnected, the hydraulic oil flows to the one-way valve 25, and the hydraulic station operates at high pressure.

[0027] When the above hydraulic system is working, the hydraulic station 1 is always open, the oil suction filter 12 sucks oil from the oil tank 18 and supplies it to the high and low pressure valve group 2. The system high pressure oil must pass through the high and low pressure valve group 2 to reach the actuator valve group 3, and the system return oil passes through the return oil filter 15 and the water cooler 14 to return to the oil tank 18. The overflow valve 24 acts as a safety valve. When the system pressure is overloaded, it starts to overflow to protect the system safety; when the hydraulic system or accumulator 22 needs to be depressurized, the manual stop valve 26 can be directly opened to drain the oil.

[0028] The above hydraulic system can switch between high and low pressure through the high and low pressure valve group 2. When the system is in a low pressure state where the pressure of the accumulator 22 is insufficient, the system pressure is at a low pressure value, and the hydraulic station 1 switches to high pressure operation and replenishes oil to the accumulator 22 until the system pressure returns to the high pressure value; when the accumulator 22 replenishes oil until the system is in a high pressure state, the hydraulic station 1 switches to low pressure operation. Through the high and low pressure switching of the hydraulic station 1, the machine tool can respond quickly and run smoothly, and the thermal balance of the hydraulic system can be ensured.

Claims

1. A high-frequency hydraulic system for a machine tool, characterized in that: It includes a hydraulic station, a high-low pressure valve group and an actuator valve group. The hydraulic station includes a motor pump group, an oil suction filter, a water cooler, an oil return filter and an oil tank. The oil suction filter and the water cooler are respectively connected to the inner cavity of the oil tank. The oil suction filter, the motor pump group, the high-low pressure valve group, the oil return filter, the water cooler and the oil tank are sequentially connected to form a loop. The high-low pressure valve group includes a one-way valve, a pressure switch, a pressure gauge, an accumulator, a manual stop valve, a relief valve and a zero-leakage on-off valve. The one-way valve, the pressure switch, the pressure gauge, the accumulator and the manual stop valve are sequentially connected in series, and then connected in parallel with the relief valve and the zero-leakage on-off valve respectively after the series connection. The one-way valve is connected in series with the motor pump group, the manual stop valve is connected in series with the oil return filter, and the two ends of the manual stop valve are respectively connected to the actuator valve group. The pressure switch is used to set the high pressure value and the low pressure value of the hydraulic system, and the zero-leakage on-off valve is used to switch the high and low pressure operation actions of the hydraulic station.

2. A high-frequency hydraulic system for a machine tool according to claim 1, characterized in that: The hydraulic station also includes a liquid level and liquid temperature switch, a refueling port and a liquid level gauge. The liquid level and liquid temperature switch is connected to the inner cavity of the oil tank, the refueling port is arranged on the top of the oil tank, and the liquid level gauge is installed on the inner wall of the oil tank.

3. A high-frequency hydraulic system for a machine tool according to claim 2, characterized in that: The liquid level gauge is a visual liquid level gauge, and the refueling port is equipped with an air filter.

4. A high-frequency hydraulic system for a machine tool according to claim 1, characterized in that: When the coil on the zero-leakage on-off valve loses power, the zero-leakage on-off valve is turned on, and the oil from the motor pump group flows to the return oil filter through the zero-leakage on-off valve, and the hydraulic station operates at low pressure; when the coil on the zero-leakage on-off valve is energized, the zero-leakage on-off valve is disconnected, the hydraulic oil flows to the one-way valve, and the hydraulic station operates at high pressure.

5. The high-frequency hydraulic system for a machine tool according to claim 1, characterized in that: The pressure switch has at least two alarm points.

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