Anti-tilting load static pressure system for precision machine tool

Abstract

This disclosure proposes an anti-eccentric load hydrostatic system for precision machine tools, comprising: an oil supply system and multiple oil supply branches; wherein, each oil supply branch includes: a capillary flow tube and a flow compensation unit; the flow compensation unit is disposed between the oil inlet end of the capillary flow tube and the oil outlet end of the oil supply system; each oil pressure acquisition unit is sequentially connected and used to output the maximum oil pressure in each hydrostatic oil chamber; the flow compensation unit corresponding to the maximum oil pressure is used to maintain the hydraulic resistance of the passage between the corresponding capillary flow tube inlet end and the oil supply system outlet end, and the remaining flow compensation units are used to adjust the hydraulic resistance of the passage between the corresponding capillary flow tube inlet end and the oil supply system outlet end according to the maximum oil pressure, so as to balance the oil flow in each hydrostatic oil chamber. In the anti-eccentric load hydrostatic system for precision machine tools of this disclosure, the flow balance of each hydrostatic oil chamber under eccentric load conditions is ensured, thereby ensuring the stable and accurate operation of the machine tool.

Description

Technical Field

[0001] This disclosure relates to the field of precision machine tool technology, and more particularly to an anti-eccentric static pressure system for precision machine tools. Background Technology

[0002] Precision CNC machine tools are key equipment in industries such as energy and power, aerospace, defense, and automobile manufacturing. The precision level of the machine tool directly determines the accuracy, efficiency, and reliability of machining large, critical parts. Hydrostatic bearings, with their superior performance characteristics such as high load-bearing capacity, low power consumption, high motion accuracy, strong vibration resistance, and long service life, are widely used in large, heavy-duty precision machine tools.

[0003] In constant pressure hydrostatic systems, hydrostatic supports with multiple oil pads or multiple oil chambers use a single oil pump for oil supply. Under eccentric load conditions, the flow rates of each hydrostatic oil chamber differ due to the different external forces they are subjected to. This causes problems such as tilting of the turntable, guide rail, and spindle due to eccentric load, ultimately leading to deviations in the machining process and affecting the machining accuracy. Summary of the Invention

[0004] This disclosure aims to at least partially address one of the technical problems in the related art.

[0005] Therefore, the purpose of this disclosure is to provide an anti-eccentric hydrostatic system for precision machine tools.

[0006] To achieve the above objectives, this disclosure provides an anti-eccentric load hydrostatic system for a precision machine tool, comprising: an oil supply system and multiple oil supply branches; wherein, the multiple oil supply branches are respectively disposed between the oil outlet end of the oil supply system and the oil inlet end of multiple hydrostatic oil chambers in the machine tool, and each oil supply branch includes: a capillary flow tube and a flow compensation unit; the oil inlet end of the capillary flow tube is connected to the oil outlet end of the oil supply system, and the oil outlet end of the capillary flow tube is connected to the oil inlet end of the hydrostatic oil chamber; the flow compensation unit is disposed between the oil inlet end of the capillary flow tube and the oil outlet end of the oil supply system. Between the ends; an oil pressure acquisition unit is provided between the oil outlet ends of adjacent capillary flow tubes, and each of the oil pressure acquisition units is connected in sequence and used to output the maximum oil pressure in the oil pressure of each static pressure oil chamber. The flow compensation unit corresponding to the maximum oil pressure is used to maintain the liquid resistance of the passage between the oil inlet end of the corresponding capillary flow tube and the oil outlet end of the oil supply system, and the remaining flow compensation units are used to adjust the liquid resistance of the passage between the oil inlet end of the corresponding capillary flow tube and the oil outlet end of the oil supply system according to the maximum oil pressure, so as to make the oil flow of each static pressure oil chamber balanced.

[0007] Optionally, the oil pressure acquisition unit includes: a shuttle valve; wherein, a plurality of capillary flow tubes and a plurality of shuttle valves are arranged sequentially; the first oil inlet end of the first shuttle valve is connected to the oil outlet end of the first capillary flow tube, and the second oil inlet end of the first shuttle valve is connected to the oil outlet end of the second capillary flow tube; the first oil inlet end of the Nth shuttle valve is connected to the oil outlet end of the (N-1)th shuttle valve, and the second oil inlet end of the Nth shuttle valve is connected to the oil outlet end of the (N+1)th capillary flow tube, where N is an integer greater than 1; the oil outlet end of the last shuttle valve is connected to the control end of each of the flow compensation units, and the oil pressure at the oil outlet end of the last shuttle valve is the maximum oil pressure among the oil pressures of each of the hydrostatic oil chambers.

[0008] Optionally, the oil pressure acquisition unit further includes: a first overflow valve, the oil inlet of the first overflow valve being connected to the oil outlet of the last shuttle valve, and the overflow end of the first overflow valve being connected to the return end of the oil supply system.

[0009] Optionally, the flow compensation unit includes: a flow compensation valve, which is disposed between the oil inlet end of the capillary flow tube and the oil outlet end of the oil supply system, and the oil inlet end of the flow compensation valve is connected to the oil outlet end of the oil supply system, the oil outlet end of the flow compensation valve is connected to the oil inlet end of the capillary flow tube, and the control end of the flow compensation valve is connected to the oil outlet end of the last shuttle valve; wherein, when the oil pressure at the oil outlet end of the last shuttle valve increases, the flow compensation valve corresponding to the maximum oil pressure is used to maintain the hydraulic resistance of the passage between the corresponding capillary flow tube inlet end and the oil outlet end of the oil supply system, and the remaining flow compensation valves are used to increase the hydraulic resistance of the passage between the corresponding capillary flow tube inlet end and the oil outlet end of the oil supply system according to the maximum oil pressure, so as to reduce the oil flow rate of the corresponding static pressure oil chamber and make the oil flow rate of each static pressure oil chamber balanced.

[0010] Optionally, the oil supply system includes: an oil return unit, an oil storage unit, a circulating cooling and filtration unit, and an oil supply unit; wherein, the oil return end of the oil return unit is connected to the oil outlet end of the machine tool's bed oil sump, and the oil outlet end of the oil return unit is connected to the oil inlet end of the oil storage unit, and the oil return unit is used for filtering the oil at the oil outlet end of the bed oil sump; the oil inlet end of the circulating cooling and filtration unit is connected to the oil outlet end of the oil storage unit, and the oil outlet end of the circulating cooling and filtration unit is connected to the oil inlet end of the oil storage unit, and the circulating cooling and filtration unit is used for cooling and filtering the oil in the oil storage unit; the oil inlet end of the oil supply unit is connected to the oil outlet end of the circulating cooling and filtration unit, and the oil outlet end of the oil supply unit is connected to the oil inlet end of each capillary flow tube, and the oil supply unit is used to deliver pressurized oil to each capillary flow tube.

[0011] Optionally, the oil supply unit includes: a motor pump set, a first filter, a first check valve, a reducing pipe, a second overflow valve, and a first pressure gauge; wherein, the oil inlet of the motor pump set is connected to the oil outlet of the circulating cooling filter unit, and the oil outlet of the motor pump set is connected to the oil inlet of the first filter, the oil outlet of the first filter is connected to the oil inlet of the first check valve, and the oil outlet of the first check valve is connected to the oil inlet of each of the capillary drain pipes; the reducing pipe is disposed between the oil outlet of the circulating cooling filter unit and the oil inlet of the oil storage unit, and the larger end of the reducing pipe is connected to the oil outlet of the circulating cooling filter unit, and the smaller end of the reducing pipe is connected to the oil inlet of the oil storage unit; the oil inlet of the second overflow valve is connected to the oil outlet of the motor pump set, and the overflow end of the second overflow valve is connected to the larger end of the reducing pipe; the detection end of the first pressure gauge is disposed between the oil outlet of the motor pump set and the oil inlet of the first filter.

[0012] Optionally, the circulating cooling and filtering unit includes: a circulating pump group, a second filter, a cooler, a third overflow valve, and a second pressure gauge; wherein, the oil inlet of the circulating pump group is connected to the oil outlet of the oil storage unit, and the oil outlet of the circulating pump group is connected to the oil inlet of the second filter, the oil outlet of the second filter is connected to the oil inlet of the cooler, and the oil outlet of the cooler is connected to the oil inlet of the oil storage unit; the cooler is used to cool the oil in the oil storage unit so that the oil temperature in the oil storage tank is within a preset temperature range; the oil inlet of the third overflow valve is connected to the oil outlet of the circulating pump group, and the overflow end of the third overflow valve is connected to the oil inlet of the oil storage unit; the detection end of the second pressure gauge is located at the oil outlet of the circulating pump group.

[0013] Optionally, the oil storage unit includes: an oil tank, a first partition, a second partition, a temperature transmitter, and a heater; wherein the first partition and the second partition are spaced apart within the oil tank, and a first overflow port is provided between the top of the first partition and the top of the oil tank, and a second overflow port is provided between the top of the second partition and the top of the oil tank; the detection end of the temperature transmitter is located on the side of the second partition away from the first partition, and the heating end of the heater is located between the first partition and the second partition, the heater being used to heat the oil in the oil tank according to the temperature detected by the temperature transmitter, so that the oil temperature in the oil tank is within a preset temperature range.

[0014] Optionally, the oil storage unit further includes: an air filter, a thermometer, a liquid level sensor, and a liquid level gauge; wherein the air filter is disposed at the ventilation end of the oil storage tank, the detection end of the thermometer is disposed between the first partition and the second partition, the detection end of the liquid level sensor is disposed between the first partition and the second partition, and the liquid level gauge is disposed on the oil storage tank, and the liquid level gauge is located on the side of the second partition away from the first partition.

[0015] Optionally, the oil return unit includes a second one-way valve and a third filter; wherein the oil inlet of the second one-way valve is connected to the oil outlet of the bed oil sump, and the oil outlet of the second one-way valve is connected to the oil inlet of the third filter, and the oil outlet of the third filter is connected to the oil inlet of the oil storage unit.

[0016] The technical solution provided in this disclosure may include the following beneficial effects:

[0017] Because the inlet end of the capillary sprue is connected to the outlet end of the oil supply system, and the outlet end of the capillary sprue is connected to the inlet end of the hydrostatic oil chamber, the oil supply system can use each capillary sprue to deliver pressurized oil to each hydrostatic oil chamber in the machine tool. Furthermore, an oil pressure acquisition unit is arranged after the capillary sprue used for throttling, and the maximum oil pressure in each hydrostatic oil chamber is selected by each oil pressure acquisition unit. In addition, a flow compensation unit is arranged before the capillary sprue used for throttling, and each flow compensation unit adjusts the hydraulic resistance of the passage between the inlet end of the corresponding capillary sprue and the outlet end of the oil supply system according to the maximum oil pressure, thereby adjusting the oil flow rate of the corresponding hydrostatic oil chamber. This ensures that the flow rate of each hydrostatic oil chamber is balanced under off-center load conditions, thereby ensuring the stable and accurate operation of the machine tool.

[0018] Additional aspects and advantages of this disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this disclosure. Attached Figure Description

[0019] The above and / or additional aspects and advantages of this disclosure will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, in which: Figure 1 This is a schematic diagram of the structure of an anti-eccentric load hydrostatic system for precision machine tools according to an embodiment of this disclosure; Figure 2 This is a partial schematic diagram of the oil supply branch in an anti-eccentric load hydrostatic system for precision machine tools according to an embodiment of this disclosure; Figure 3 This is a partial schematic diagram of the oil supply system in an anti-eccentric load hydrostatic system for a precision machine tool according to an embodiment of this disclosure; As shown in the figure: 1. Fuel supply branch; 11. Capillary flow pipe; 12. Flow compensation unit; 13. Oil pressure acquisition unit; 14. First relief valve; 2. Oil supply system; 21. Oil return unit; 211. Second check valve; 212. Third filter; 22. Oil storage unit; 221. Oil tank; 222. First partition; 223. Second partition; 224. Temperature transmitter; 225. Heater; 226. Air filter; 227. Thermometer; 228. Liquid level sensor; 229. Liquid level gauge. 23. Circulating cooling filter unit; 231. Circulating pump set; 232. Second filter; 233. Cooler; 234. Third overflow valve; 235. Second pressure gauge. 24. Oil supply unit; 241. Motor pump set; 242. First filter; 243. First check valve; 244. Reducer; 245. Second relief valve; 246. First pressure gauge. 3. Static pressure oil chamber; 4. Bed oil pool. Detailed Implementation

[0020] Embodiments of this disclosure are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are used only to explain this disclosure, and should not be construed as limiting this disclosure. Rather, embodiments of this disclosure include all variations, modifications, and equivalents falling within the spirit and scope of the appended claims.

[0021] like Figure 1 and Figure 2As shown in the figure, this disclosure proposes an anti-eccentric load hydrostatic system for a precision machine tool, including: an oil supply system 2 and multiple oil supply branches 1. The multiple oil supply branches 1 are respectively disposed between the oil outlet of the oil supply system 2 and the oil inlet of multiple hydrostatic oil chambers 3 in the machine tool, and each oil supply branch 1 includes: a capillary flow tube 11 and a flow compensation unit 12; the oil inlet of the capillary flow tube 11 is connected to the oil outlet of the oil supply system 2, and the oil outlet of the capillary flow tube 11 is connected to the oil inlet of the hydrostatic oil chamber 3; the flow compensation unit 12 is disposed between the oil inlet of the capillary flow tube 11 and the oil outlet of the oil supply system 2; and a system is provided between the oil outlets of adjacent capillary flow tubes 11. There is an oil pressure acquisition unit 13, and each oil pressure acquisition unit 13 is connected in sequence and used to output the maximum oil pressure in each static pressure oil chamber 3. The flow compensation unit 12 corresponding to the maximum oil pressure is used to maintain the liquid resistance of the passage between the oil inlet end of the corresponding capillary sprue 11 and the oil outlet end of the oil supply system 2. The remaining flow compensation units 12 are used to adjust the liquid resistance of the passage between the oil inlet end of the corresponding capillary sprue 11 and the oil outlet end of the oil supply system 2 according to the maximum oil pressure, so as to make the oil flow of each static pressure oil chamber 3 balanced.

[0022] It is understandable that, since the oil inlet end of the capillary flow tube 11 is connected to the oil outlet end of the oil supply system 2, and the oil outlet end of the capillary flow tube 11 is connected to the oil inlet end of the hydrostatic oil chamber 3, the oil supply system 2 can use each capillary flow tube 11 to deliver pressurized oil to each hydrostatic oil chamber 3 in the machine tool. Furthermore, an oil pressure acquisition unit 13 is arranged after the capillary flow tube 11 used for throttling, and the maximum oil pressure in each hydrostatic oil chamber 3 is selected by each oil pressure acquisition unit 13. In addition, a flow compensation unit 12 is arranged before the capillary flow tube 11 used for throttling, and each flow compensation unit 12 adjusts the hydraulic resistance of the passage between the oil inlet end of the corresponding capillary flow tube 11 and the oil outlet end of the oil supply system 2 according to the maximum oil pressure, thereby adjusting the oil flow of the corresponding hydrostatic oil chamber 3, thereby ensuring the flow balance of each hydrostatic oil chamber 3 under off-center load conditions, and thus ensuring the stable and accurate operation of the machine tool.

[0023] It should be noted that the pressurized oil supplied by the oil supply system 2 enters each static pressure oil chamber 3 of the machine tool after passing through each capillary flow pipe 11. Furthermore, based on the cooperation of the flow compensation unit 12 and the oil pressure acquisition unit 13, the hydraulic resistance of each oil supply branch 1 can be dynamically adjusted according to the maximum load to ensure the normal operation of the turntable, guide rail, spindle, etc. under off-center load conditions.

[0024] For example, assuming a non-eccentric load condition, the internal pressure of a certain hydrostatic oil chamber 3 increases due to increased load, and the oil flow rate of this hydrostatic oil chamber 3 decreases accordingly. Meanwhile, the internal pressure of the other hydrostatic oil chambers 3 remains unchanged due to constant load, and their oil flow rates also remain constant. In this case, each oil pressure acquisition unit 13 selects the maximum pressure as the control oil source for the flow compensation unit 12. The flow compensation unit 12 adjusts the cross-sectional dimensions of the passage according to the control oil source, thereby maintaining the hydraulic resistance of the oil supply circuit of the high-pressure hydrostatic oil chamber 3 unchanged, while increasing the hydraulic resistance of the oil supply circuit of the other hydrostatic oil chambers 3, thus achieving a balance in the oil flow rates between the high-pressure hydrostatic oil chamber 3 and the other hydrostatic oil chambers 3.

[0025] Among them, the capillary flow tube 11 is a capillary oil tube used for throttling. Each static pressure oil chamber 3 corresponds to one capillary flow tube 11. The specific type of capillary flow tube 11 can be set according to actual needs and there is no restriction on it.

[0026] In some embodiments, the oil pressure acquisition unit 13 includes a shuttle valve. Multiple capillary flow tubes 11 and multiple shuttle valves are arranged sequentially. The first inlet of the first shuttle valve is connected to the outlet of the first capillary flow tube 11, and the second inlet of the first shuttle valve is connected to the outlet of the second capillary flow tube 11. The first inlet of the Nth shuttle valve is connected to the outlet of the (N-1)th shuttle valve, and the second inlet of the Nth shuttle valve is connected to the outlet of the (N+1)th capillary flow tube 11, where N is an integer greater than 1. The outlet of the last shuttle valve is connected to the control terminal of each flow compensation unit 12, and the oil pressure at the outlet of the last shuttle valve is the maximum oil pressure among the oil pressures of each hydrostatic oil chamber 3.

[0027] It is understandable that, since the first inlet of the first shuttle valve is connected to the outlet of the first capillary flow tube 11, and the second inlet of the first shuttle valve is connected to the outlet of the second capillary flow tube 11, the oil pressure output from the outlet of the first shuttle valve is the maximum oil pressure between the outlets of the first and second capillary flow tubes 11. Furthermore, since the first inlet of the Nth shuttle valve is connected to the outlet of the (N-1)th shuttle valve, and the second inlet of the Nth shuttle valve is connected to the outlet of the (N+1)th capillary flow tube 11... The oil outlet of the last shuttle valve is connected to the oil outlet of the last shuttle valve, so that the oil pressure at the oil outlet of the last shuttle valve is the maximum oil pressure among the oil pressures of each hydrostatic oil chamber 3. This achieves the selection of the maximum oil pressure. At the same time, based on the fact that the oil outlet of the last shuttle valve is connected to the control end of each flow compensation unit 12, the oil pressure acquisition unit 13 and the flow compensation unit 12 are effectively linked, so that each flow compensation unit 12 can adjust the oil flow at the oil inlet of the corresponding capillary sprue 11 according to the maximum oil pressure, thereby ensuring the stable and accurate operation of the machine tool.

[0028] It should be noted that the shuttle valve is installed after the capillary sprue 11, and the pressure it collects is the pressure after the capillary sprue 11 is throttled. Since the liquid resistance of the capillary sprue 11 is much greater than the liquid resistance of the subsequent pipeline, the liquid resistance between the capillary sprue 11 and the static pressure oil chamber 3 can be ignored. That is, the pressure collected by the shuttle valve is the pressure generated when the static pressure oil chamber 3 is working.

[0029] For example, if the oil pressure at the oil outlet of the first capillary flow tube 11 is greater than the oil pressure at the oil outlet of the second capillary flow tube 11, then the oil pressure at the oil outlet of the first shuttle valve is the same as the oil pressure at the oil outlet of the first capillary flow tube 11; otherwise, the oil pressure at the oil outlet of the first shuttle valve is the same as the oil pressure at the oil outlet of the second capillary flow tube 11.

[0030] For example, in the oil outlet of the third capillary flow tube 11 and the oil outlet of the first shuttle valve, if the oil pressure of the third capillary flow tube 11 is greater than the oil pressure of the first shuttle valve, then the oil pressure of the second shuttle valve is the same as the oil pressure of the third capillary flow tube 11. Otherwise, the oil pressure of the second shuttle valve is the same as the oil pressure of the first shuttle valve. In other words, the oil pressure of the second shuttle valve is the maximum oil pressure among the oil pressures of the first, second, and third capillary flow tubes 11.

[0031] As can be seen from the above example, the oil pressure at the outlet of the last shuttle valve is the maximum oil pressure among the oil pressures of each hydrostatic oil chamber 3, thus completing the maximum pressure screening.

[0032] like Figure 2 As shown, in some embodiments, the oil pressure acquisition unit 13 further includes: a first overflow valve 14, the oil inlet end of the first overflow valve 14 is connected to the oil outlet end of the last shuttle valve, and the overflow end of the first overflow valve 14 is connected to the return end of the oil supply system 2.

[0033] It is understandable that, since the oil inlet of the first relief valve 14 is connected to the oil outlet of the last shuttle valve, and the oil overflow end of the first relief valve 14 is connected to the oil return end of the oil supply system 2, when the maximum oil pressure screened by each shuttle valve is too high, the overflow of the first relief valve 14 can be used to achieve protection, thereby ensuring the safe operation of the system.

[0034] It should be noted that the first relief valve 14 is used for oil pressure protection in each static pressure oil chamber 3. The specific type of the first relief valve 14 can be set according to actual needs, and there are no restrictions on it.

[0035] In some embodiments, the flow compensation unit 12 includes: a flow compensation valve, which is disposed between the oil inlet end of the capillary sprue 11 and the oil outlet end of the oil supply system 2, and the oil inlet end of the flow compensation valve is connected to the oil outlet end of the oil supply system 2, the oil outlet end of the flow compensation valve is connected to the oil inlet end of the capillary sprue 11, and the control end of the flow compensation valve is connected to the oil outlet end of the last shuttle valve. When the oil pressure at the oil outlet end of the last shuttle valve increases, the flow compensation valve corresponding to the maximum oil pressure is used to maintain the hydraulic resistance of the passage between the corresponding capillary sprue 11 oil inlet end and the oil outlet end of the oil supply system 2, and the remaining flow compensation valves are used to increase the hydraulic resistance of the passage between the corresponding capillary sprue 11 oil inlet end and the oil outlet end of the oil supply system 2 according to the maximum oil pressure, thereby reducing the oil flow rate of the corresponding static pressure oil chamber 3 and balancing the oil flow rate of each static pressure oil chamber 3.

[0036] Understandably, when the oil pressure at the outlet of the last shuttle valve increases, the oil flow rate in the static pressure chamber 3 corresponding to the maximum oil pressure decreases due to the increased pressure. The flow compensation valve corresponding to the maximum oil pressure maintains the hydraulic resistance of the passage between the inlet of the corresponding capillary sprue 11 and the outlet of the oil supply system 2. In addition, the other flow compensation valves reduce the oil flow rate in the corresponding static pressure chamber 3 according to the increase in hydraulic resistance of the passage between the inlet of the corresponding capillary sprue 11 and the outlet of the oil supply system 2 based on the maximum oil pressure. This achieves a balance of oil flow rate between the static pressure chamber 3 corresponding to the maximum oil pressure and the other static pressure chambers 3, thereby ensuring the stable and accurate operation of the machine tool.

[0037] Specifically, the pressure of each branch is filtered by each shuttle valve to select the maximum pressure as the control oil source for each flow compensation valve, thereby controlling the valve core position of each branch flow compensation valve and thus controlling the flow into each branch.

[0038] The specific type of flow compensation valve can be set according to actual needs, and there are no restrictions on it.

[0039] According to the formula To further explain, Q is the oil flow rate in the hydrostatic oil chamber 3, and R is the hydraulic resistance of the oil supply circuit. The input-output pressure difference of the oil supply circuit.

[0040] For example, without a flow compensation valve, the load on a certain static pressure oil chamber 3 increases. This increased load leads to an increase in the output pressure of the oil supply circuit. However, based on the constant hydraulic resistance, The reduction in the load causes the oil flow rate Q of the hydrostatic oil chamber 3 to decrease. The load of the other hydrostatic oil chambers 3 remains unchanged, and their oil flow rate Q also remains unchanged, thus causing an off-center load.

[0041] When the flow compensation valve is set, the load on a certain static pressure oil chamber 3 increases. The increased load leads to an increase in the output pressure of the oil supply circuit, while the hydraulic resistance R remains constant. The reduction in pressure causes the oil flow rate Q of the static pressure oil chamber 3 to decrease. This static pressure oil chamber 3 is the static pressure oil chamber 3 corresponding to the maximum oil pressure. The corresponding flow compensation valve keeps the hydraulic resistance unchanged, thereby maintaining the static pressure oil chamber 3 at the current reduced oil flow rate.

[0042] In addition, the other flow compensation valves increase the corresponding circuit's hydraulic resistance R based on the maximum oil pressure, while... The hydraulic resistance R remains unchanged, but the increase in hydraulic resistance R leads to a decrease in the hydraulic flow rate Q of the hydrostatic oil chamber 3, thereby achieving the same hydraulic flow rate Q in each hydrostatic oil chamber 3 and achieving balanced anti-eccentric load.

[0043] like Figure 1 As shown, in some embodiments, the oil supply system 2 includes: an oil return unit 21, an oil storage unit 22, a circulating cooling and filtering unit 23, and an oil supply unit 24. The oil return unit 21 has its oil return end connected to the oil outlet end of the machine tool's bed oil sump 4, and its oil outlet end connected to the oil inlet end of the oil storage unit 22. The oil return unit 21 is used for filtering the oil at the oil outlet end of the bed oil sump 4. The circulating cooling and filtering unit 23 has its oil inlet end connected to the oil outlet end of the oil storage unit 22, and its oil outlet end connected to the oil inlet end of the oil storage unit 22. The circulating cooling and filtering unit 23 is used for cooling and filtering the oil in the oil storage unit 22. The oil supply unit 24 has its oil inlet end connected to the oil outlet end of the circulating cooling and filtering unit 23, and its oil outlet end connected to the oil inlet end of each capillary flow tube 11. The oil supply unit 24 is used to supply pressurized oil to each capillary flow tube 11.

[0044] Understandably, since the oil return end of the oil return unit 21 is connected to the oil outlet end of the machine tool's bed oil sump 4, and the oil outlet end of the oil return unit 21 is connected to the oil inlet end of the oil storage unit 22, the oil return unit 21 can recover the oil from the bed oil sump 4 to the oil storage unit 22. Furthermore, since the oil inlet end of the circulating cooling filter unit 23 is connected to the oil outlet end of the oil storage unit 22, and the oil outlet end of the circulating cooling filter unit 23 is connected to the oil inlet end of the oil storage unit 22, the circulating cooling filter unit 23 can cool and filter the oil in the oil storage unit 22. At the same time, since the oil inlet end of the oil supply unit 24 is connected to the oil outlet end of the circulating cooling filter unit 23, and the oil outlet end of the oil supply unit 24 is connected to the oil inlet end of each capillary flow tube 11, the oil supply unit 24 can pressurize and deliver the oil in the oil storage unit 22 to each capillary flow tube 11, and then to each hydrostatic oil chamber 3, ensuring the stable and precise operation of the machine tool.

[0045] like Figure 2As shown, in some embodiments, the oil supply unit 24 includes: a motor pump assembly 241, a first filter 242, a first check valve 243, a reducer 244, a second overflow valve 245, and a first pressure gauge 246. The oil inlet of the motor pump assembly 241 is connected to the oil outlet of the circulating cooling filter unit 23, and the oil outlet of the motor pump assembly 241 is connected to the oil inlet of the first filter 242. The oil outlet of the first filter 242 is connected to the oil inlet of the first check valve 243, and the oil outlet of the first check valve 243 is connected to the oil inlet of each capillary drain pipe 11. The reducer 244 is disposed between the oil outlet of the circulating cooling filter unit 23 and the oil inlet of the oil storage unit 22. The larger end of the reducing pipe 244 is connected to the oil outlet of the circulating cooling filter unit 23, and the smaller end of the reducing pipe 244 is connected to the oil inlet of the oil storage unit 22; the oil inlet of the second overflow valve 245 is connected to the oil outlet of the motor pump unit 241, and the overflow end of the second overflow valve 245 is connected to the larger end of the reducing pipe 244; the detection end of the first pressure gauge 246 is located between the oil outlet of the motor pump unit 241 and the oil inlet of the first filter 242.

[0046] Understandably, since the oil inlet of the motor pump unit 241 is connected to the oil outlet of the circulating cooling filter unit 23, and the oil outlet of the motor pump unit 241 is connected to the oil inlet of the first filter 242, the oil outlet of the first filter 242 is connected to the oil inlet of the first one-way valve 243, and the oil outlet of the first one-way valve 243 is connected to the oil inlet of each capillary slit pipe 11, the oil in the oil storage unit 22 is pumped by the motor pump unit 241, the first filter 242 and the first one-way valve 243 in sequence and then transported to each capillary slit pipe 11, and then to each static pressure oil chamber 3. At the same time, the filtration of the first filter 242 and the one-way conduction of the first one-way valve 243 further ensure the safe operation of the system.

[0047] Since the larger end of the reducing pipe 244 is connected to the oil outlet of the circulating cooling filter unit 23 and the smaller end of the reducing pipe 244 is connected to the oil inlet of the oil storage unit 22, the oil pipe diameter becomes smaller after the oil outlet of the circulating cooling filter unit 23, which generates a certain pressure in the pipeline before the reducing pipe diameter, thereby improving the oil suction capacity of the motor pump unit 241.

[0048] Since the oil inlet of the second overflow valve 245 is connected to the oil outlet of the motor pump unit 241, and the overflow end of the second overflow valve 245 is connected to the larger end of the reducer 244, the overflow of the second overflow valve 245 can be used to protect the system when the oil pressure at the oil outlet of the motor pump unit 241 is too high, thus ensuring the safe operation of the system.

[0049] The detection end of the first pressure gauge 246 is located between the oil outlet of the motor pump unit 241 and the oil inlet of the first filter 242, so that the system can use the first pressure gauge 246 to monitor the oil pressure at the oil outlet of the motor pump unit 241.

[0050] Among them, the motor pump set 241 is used to pump oil, the first filter 242 is used to filter oil, the first check valve 243 is used to unidirectionally guide oil, the reducer 244 is used to reduce the oil pipe diameter and provide oil pressure before the diameter change, the second relief valve 245 is used for oil overpressure protection, and the first pressure gauge 246 is used to display the oil pressure at the oil outlet of the motor pump set 241. The specific types of the motor pump set 241, the first filter 242, the first check valve 243, the reducer 244, the second relief valve 245 and the first pressure gauge 246 can be set according to actual needs and there is no restriction on them.

[0051] like Figure 3 As shown, in some embodiments, the circulating cooling filter unit 23 includes: a circulating pump group 231, a second filter 232, a cooler 233, a third overflow valve 234, and a second pressure gauge 235. The oil inlet of the circulating pump group 231 is connected to the oil outlet of the oil storage unit 22, and the oil outlet of the circulating pump group 231 is connected to the oil inlet of the second filter 232. The oil outlet of the second filter 232 is connected to the oil inlet of the cooler 233, and the oil outlet of the cooler 233 is connected to the oil inlet of the oil storage unit 22. The cooler 233 is used to cool the oil in the oil storage unit 22 to keep the oil temperature in the oil storage tank 221 within a preset temperature range. The oil inlet of the third overflow valve 234 is connected to the oil outlet of the circulating pump group 231, and the overflow end of the third overflow valve 234 is connected to the oil inlet of the oil storage unit 22. The detection end of the second pressure gauge 235 is located at the oil outlet of the circulating pump group 231.

[0052] Understandably, since the oil inlet of the circulating pump set 231 is connected to the oil outlet of the oil storage unit 22, and the oil outlet of the circulating pump set 231 is connected to the oil inlet of the second filter 232, the oil outlet of the second filter 232 is connected to the oil inlet of the cooler 233, and the oil outlet of the cooler 233 is connected to the oil inlet of the oil storage unit 22, the oil in the oil storage unit 22 is pumped by the circulating pump set 231, passes through the circulating pump set 231, the second filter 232 and the cooler 233 in sequence and then returns to the oil storage unit 22. At the same time, the filtration of the second filter 232 and the cooling of the cooler 233 ensure that the oil in the oil storage unit 22 is within the preset cleanliness range and preset temperature range, further ensuring the safe operation of the system.

[0053] Since the oil inlet of the third overflow valve 234 is connected to the oil outlet of the circulating pump group 231, and the overflow end of the third overflow valve 234 is connected to the oil inlet of the oil storage unit 22, the overflow of the third overflow valve 234 can be used to protect the system when the oil pressure at the oil outlet of the circulating pump group 231 is too high, thereby ensuring the safe operation of the system.

[0054] The detection end of the second pressure gauge 235 is set at the oil outlet of the circulating pump group 231, so that the system can use the second pressure gauge 235 to monitor the oil pressure at the oil outlet of the circulating pump group 231.

[0055] The circulating pump set 231 is used to pump oil, the second filter 232 is used to filter oil, the cooler 233 is used to cool oil, the third relief valve 234 is used for overpressure protection of oil, and the second pressure gauge 235 is used to display the oil pressure at the oil outlet of the motor pump set 241. The specific types of the circulating pump set 231, the second filter 232, the cooler 233, the third relief valve 234, and the second pressure gauge 235 can be set according to actual needs and are not restricted.

[0056] like Figure 3 As shown, in some embodiments, the oil storage unit 22 includes: an oil tank 221, a first partition 222, a second partition 223, a temperature transmitter 224, and a heater 225; wherein, the first partition 222 and the second partition 223 are spaced apart within the oil tank 221, and a first overflow port is provided between the top of the first partition 222 and the top of the oil tank 221, and a second overflow port is provided between the top of the second partition 223 and the top of the oil tank 221; the detection end of the temperature transmitter 224 is located on the side of the second partition 223 away from the first partition 222, and the heating end of the heater 225 is located between the first partition 222 and the second partition 223, and the heater 225 is used to heat the oil in the oil tank 221 according to the temperature detected by the temperature transmitter 224, so that the temperature of the oil in the oil tank 221 is within a preset temperature range.

[0057] Understandably, since the first partition 222 and the second partition 223 are spaced apart inside the oil storage tank 221, and a first overflow port is provided between the top of the first partition 222 and the top of the oil storage tank 221, and a second overflow port is provided between the top of the second partition 223 and the top of the oil storage tank 221, the oil storage tank 221 is divided into three continuous chambers by the first partition 222 and the second partition 223. As a result, the oil undergoes multiple settling and heat dissipation processes through the first overflow port and the second overflow port in sequence, and finally reaches the oil outlet of the oil storage tank 221, thereby ensuring a high degree of cleanliness of the oil.

[0058] Furthermore, since the detection end of the temperature transmitter 224 is located on the side of the second partition 223 away from the first partition 222, and the heating end of the heater 225 is located between the first partition 222 and the second partition 223, the temperature transmitter 224 can detect the oil temperature in the oil tank 221, and the heater 225 can heat the oil in the oil tank 221 according to the temperature detected by the temperature transmitter 224, so that the oil temperature in the oil tank 221 is within the preset temperature range, thereby ensuring that the oil can work in a suitable viscosity range.

[0059] The oil storage tank 221 is used to store return oil and allow impurities in the return oil to settle. The specific type of the oil storage tank 221 can be set according to actual needs and there are no restrictions on it.

[0060] The first partition 222 and the second partition 223 are used to separate the oil storage tank 221, so that the oil storage tank 221 is divided into chambers for sequential settling. Compared with the multi-stage oil tank of related embodiments, the multi-stage settling structure of this embodiment is simpler. The specific types of the first partition 222 and the second partition 223 can be set according to actual needs and are not limited thereto. The bottom openings of the first partition 222 and the second partition 223 are staggered to extend the oil flow path and allow for secondary settling of impurities during the flow process.

[0061] Temperature transmitter 224 is used to detect the temperature of the oil in oil tank 221, and heater 225 is used to heat the oil in oil tank 221. The specific types of temperature transmitter 224 and heater 225 can be set according to actual needs and are not limited thereto. Among them, heater 225 can be used in conjunction with cooler 233.

[0062] like Figure 3 As shown, in some embodiments, the oil storage unit 22 further includes an air filter 226, a thermometer 227, a liquid level sensor 228, and a liquid level gauge 229. The air filter 226 is disposed at the ventilation end of the oil storage tank 221; the detection end of the thermometer 227 is disposed between the first partition 222 and the second partition 223; the detection end of the liquid level sensor 228 is disposed between the first partition 222 and the second partition 223; and the liquid level gauge 229 is disposed on the oil storage tank 221, with the liquid level gauge 229 located on the side of the second partition 223 away from the first partition 222.

[0063] Understandably, since the air filter 226 is located at the ventilation end of the oil reservoir 221, it can filter air, thereby preventing particulate contaminants in the air from entering the system and ensuring a high level of oil cleanliness. Since the detection end of the thermometer 227 is located between the first partition 222 and the second partition 223, it can detect and display the temperature of the oil in the oil reservoir 221, making the system more convenient to use. Since the detection end of the level sensor 228 is located between the first partition 222 and the second partition 223, it can detect the level of the oil in the oil reservoir 221, thus enabling level monitoring. Since the level gauge 229 is located on the oil reservoir 221 and on the side of the second partition 223 away from the first partition 222, it can display the oil level in the oil reservoir 221 directly, further enhancing the system's usability.

[0064] It should be noted that the air filter 226 is used to filter air, the thermometer 227 is used to detect the temperature of the oil in the oil tank 221, the level sensor 228 is used to detect the oil level in the oil tank 221, and the level gauge 229 is used to display the oil level in the oil tank 221. The specific types of the air filter 226, thermometer 227, level sensor 228, and level gauge 229 can be set according to actual needs and are not limited thereto. The level gauge 229 can be a graduated transparent plate.

[0065] like Figure 3 As shown, in some embodiments, the oil return unit 21 includes a second check valve 211 and a third filter 212. The oil inlet of the second check valve 211 is connected to the oil outlet of the bed oil sump 4, and the oil outlet of the second check valve 211 is connected to the oil inlet of the third filter 212. The oil outlet of the third filter 212 is connected to the oil inlet of the oil storage unit 22.

[0066] Understandably, since the oil inlet of the second check valve 211 is connected to the oil outlet of the bed oil sump 4, and the oil outlet of the second check valve 211 is connected to the oil inlet of the third filter 212, and the oil outlet of the third filter 212 is connected to the oil inlet of the oil storage unit 22, the oil in the bed oil sump 4 can be recovered to the oil storage unit 22 after passing through the second check valve 211 and the third filter 212 in sequence. At the same time, the one-way conduction of the second check valve 211 and the filtration of the third filter 212 further ensure the safe operation of the system.

[0067] It should be noted that the second check valve 211 is used for one-way flow of oil, and the third filter 212 is used for filtering oil. The specific types of the second check valve 211 and the third filter 212 can be set according to actual needs, and there are no restrictions on this.

[0068] In summary, the system in this embodiment solves the problems of different flow rates in each hydrostatic oil chamber 3 due to different external forces under off-center load conditions in the current constant pressure hydrostatic support system, which ultimately leads to tilting of the turntable, guide rail, spindle, etc. caused by off-center load, and ultimately causes deviations in the machining of machine tools.

[0069] It should be noted that in the description of this disclosure, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0070] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of preferred embodiments of this disclosure includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the function involved, as will be understood by those skilled in the art to which embodiments of this disclosure pertain.

[0071] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0072] Although embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A bias load resistant hydrostatic system for a precision machine tool, characterized by, include: The fuel supply system and multiple fuel supply branches; The oil supply branches are respectively arranged between the oil outlet of the oil supply system and the oil inlet of the multiple hydrostatic oil chambers in the machine tool, and the oil supply branches include: capillary flow tubes and flow compensation units. The inlet end of the capillary flow tube is connected to the outlet end of the oil supply system, and the outlet end of the capillary flow tube is connected to the inlet end of the hydrostatic oil chamber. The flow compensation unit is disposed between the inlet end of the capillary flow tube and the outlet end of the oil supply system. An oil pressure acquisition unit is provided between the oil outlet ends of adjacent capillary flow tubes, and each of the oil pressure acquisition units is connected in sequence and used to output the maximum oil pressure in each of the static pressure oil chambers. The flow compensation unit corresponding to the maximum oil pressure is used to maintain the liquid resistance of the passage between the oil inlet end of the corresponding capillary flow tube and the oil outlet end of the oil supply system, and the remaining flow compensation units are used to adjust the liquid resistance of the passage between the oil inlet end of the corresponding capillary flow tube and the oil outlet end of the oil supply system according to the maximum oil pressure, so as to make the oil flow of each of the static pressure oil chambers balanced.

2. The anti-offset load hydrostatic system for precision machine tools according to claim 1, characterized in that, The oil pressure acquisition unit includes: a shuttle valve; Among them, multiple capillary flow tubes and multiple shuttle valves are arranged in sequence; The first oil inlet end of the first shuttle valve is connected to the oil outlet end of the first capillary flow tube, and the second oil inlet end of the first shuttle valve is connected to the oil outlet end of the second capillary flow tube. The first oil inlet end of the Nth shuttle valve is connected to the oil outlet end of the (N-1)th shuttle valve, and the second oil inlet end of the Nth shuttle valve is connected to the oil outlet end of the (N+1)th capillary flow tube, where N is an integer greater than 1. The oil outlet of the last shuttle valve is connected to the control terminal of each of the flow compensation units, and the oil pressure at the oil outlet of the last shuttle valve is the maximum oil pressure among the oil pressures of each of the hydrostatic oil chambers.

3. The anti-offset load hydrostatic system for precision machine tools according to claim 2, characterized in that, The hydraulic pressure acquisition unit also includes: The first overflow valve has its inlet end connected to the outlet end of the last shuttle valve, and its overflow end is connected to the return end of the oil supply system.

4. The anti-offset load hydrostatic system for precision machine tools according to claim 2, characterized in that, The flow compensation unit includes: A flow compensation valve is provided, wherein the flow compensation valve is disposed between the oil inlet end of the capillary flow tube and the oil outlet end of the oil supply system, and the oil inlet end of the flow compensation valve is connected to the oil outlet end of the oil supply system, the oil outlet end of the flow compensation valve is connected to the oil inlet end of the capillary flow tube, and the control end of the flow compensation valve is connected to the oil outlet end of the last shuttle valve. When the oil pressure at the outlet of the last shuttle valve increases, the flow compensation valve corresponding to the maximum oil pressure is used to maintain the hydraulic resistance of the passage between the inlet of the capillary sprue and the outlet of the oil supply system. The remaining flow compensation valves are used to increase the hydraulic resistance of the passage between the inlet of the capillary sprue and the outlet of the oil supply system according to the maximum oil pressure, so as to reduce the oil flow rate of the corresponding static pressure oil chamber and make the oil flow rate of each static pressure oil chamber balanced.

5. The anti-eccentric load hydrostatic system for precision machine tools according to claim 1, characterized in that, The oil supply system includes: Oil return unit, oil storage unit, circulating cooling and filtration unit, and oil supply unit; The oil return unit is connected to the oil outlet of the machine tool bed oil sump, and the oil outlet of the oil return unit is connected to the oil inlet of the oil storage unit. The oil return unit is used to filter the oil at the oil outlet of the machine tool bed oil sump. The oil inlet of the circulating cooling filter unit is connected to the oil outlet of the oil storage unit, and the oil outlet of the circulating cooling filter unit is connected to the oil inlet of the oil storage unit. The circulating cooling filter unit is used for cooling and filtering the oil in the oil storage unit. The oil supply unit is connected to the oil outlet of the circulating cooling filter unit, and the oil outlet of the oil supply unit is connected to the oil inlet of each capillary tube. The oil supply unit is used to supply pressurized oil to each capillary tube.

6. The anti-eccentric load hydrostatic system for precision machine tools according to claim 5, characterized in that, The oil supply unit includes: The motor pump unit, the first filter, the first check valve, the reducer, the second relief valve, and the first pressure gauge; The oil inlet of the motor pump unit is connected to the oil outlet of the circulating cooling filter unit, and the oil outlet of the motor pump unit is connected to the oil inlet of the first filter. The oil outlet of the first filter is connected to the oil inlet of the first one-way valve, and the oil outlet of the first one-way valve is connected to the oil inlet of each of the capillary drain pipes. The variable diameter pipe is disposed between the oil outlet end of the circulating cooling filter unit and the oil inlet end of the oil storage unit, with the larger end of the variable diameter pipe connected to the oil outlet end of the circulating cooling filter unit and the smaller end of the variable diameter pipe connected to the oil inlet end of the oil storage unit. The oil inlet of the second overflow valve is connected to the oil outlet of the motor pump unit, and the oil overflow end of the second overflow valve is connected to the larger end of the reducing pipe. The detection end of the first pressure gauge is located between the oil outlet end of the motor pump unit and the oil inlet end of the first filter.

7. The anti-eccentric load hydrostatic system for precision machine tools according to claim 5, characterized in that, The circulating cooling filtration unit includes: Circulating pump set, second filter, cooler, third relief valve and second pressure gauge; The oil inlet of the circulating pump unit is connected to the oil outlet of the oil storage unit, and the oil outlet of the circulating pump unit is connected to the oil inlet of the second filter. The oil outlet of the second filter is connected to the oil inlet of the cooler, and the oil outlet of the cooler is connected to the oil inlet of the oil storage unit. The cooler is used to cool the oil in the oil storage unit so that the oil temperature in the oil tank is within a preset temperature range. The oil inlet of the third overflow valve is connected to the oil outlet of the circulating pump group, and the oil overflow of the third overflow valve is connected to the oil inlet of the oil storage unit. The detection end of the second pressure gauge is located at the oil outlet end of the circulating pump unit.

8. The anti-eccentric load hydrostatic system for precision machine tools according to claim 5, characterized in that, The oil storage unit includes: Oil reservoir, first partition, second partition, temperature transmitter and heater; The first partition and the second partition are spaced apart inside the oil storage tank, and a first overflow port is provided between the top of the first partition and the top of the oil storage tank, and a second overflow port is provided between the top of the second partition and the top of the oil storage tank. The detection end of the temperature transmitter is located on the side of the second partition away from the first partition, and the heating end of the heater is located between the first partition and the second partition. The heater is used to heat the oil in the oil tank according to the temperature detected by the temperature transmitter, so that the oil temperature in the oil tank is within a preset temperature range.

9. The anti-eccentric load hydrostatic system for precision machine tools according to claim 8, characterized in that, The oil storage unit also includes: Air filters, thermometers, level sensors, and level gauges; The air filter is located at the ventilation end of the oil tank, the detection end of the thermometer is located between the first partition and the second partition, the detection end of the liquid level sensor is located between the first partition and the second partition, and the liquid level gauge is located on the oil tank, with the liquid level gauge located on the side of the second partition away from the first partition.

10. The anti-eccentric load hydrostatic system for precision machine tools according to claim 5, characterized in that, The oil return unit includes: The second check valve and the third filter; The oil inlet of the second check valve is connected to the oil outlet of the bed oil sump, and the oil outlet of the second check valve is connected to the oil inlet of the third filter, while the oil outlet of the third filter is connected to the oil inlet of the oil storage unit.

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