JP5961515B2 - Cooling system - Google Patents

Description

  The technology disclosed in the present specification relates to a cooling device that cools a working fluid (for example, cooling water, cutting fluid, hydraulic oil, or the like) used in a processing machine (for example, a machine tool or a press machine) that processes a workpiece. .

  When the processing machine is operated, heat is partially generated, and it may be necessary to cool the heat generation portion. For example, in a press machine that presses a workpiece, in order to cool the mold, a working fluid such as cooling water is supplied to the mold to cool the mold. Alternatively, in a machine tool that cuts a workpiece, a working fluid such as cooling water, cutting fluid, or hydraulic oil is supplied to the machine tool to cool the machine tool. For example, in the machine tool disclosed in Patent Document 1, a cooling fluid (a kind of working fluid) that also serves as a lubricating oil is supplied to a heat generating portion of the machine tool. The cooling liquid heated by cooling the heat generating part of the machine tool is returned to the tank. The cooling liquid returned to the tank is cooled by a cooling device. The cooled coolant is again supplied to the heat generating part of the machine tool and used for cooling the heat generating part. Hereinafter, the heat generating part of the machine tool is cooled by circulating the coolant.

JP 2011-136373 A

  In the technique of Patent Document 1, in order to cool the working fluid, the cooling device circulates the refrigerant by the compressor, exchanges heat between the circulating refrigerant and the working fluid, and thereby cools the working fluid. In order to cool the working fluid, the compressor must be driven, and power (energy) for that purpose is always required. This specification provides the cooling device which can cool the working fluid used for a processing machine with little energy.

  The cooling device disclosed in the present specification cools a working fluid used in a processing machine. The cooling device includes a first flow path through which cooling water flows, a first branch flow path branched from the first flow path, a second flow path through which refrigerant flows, and a state in which cooling water flows through the first flow path. A first switching means for switching to a non-flowing state, a second switching means for switching between a state in which a refrigerant flows in the second flow path and a state in which the refrigerant does not flow, and a state in which cooling water flows through the first branch flow path A third switching means for switching to a state, a heat exchanging part for exchanging heat between the cooling water flowing through the first branch flow path and the refrigerant flowing through the second flow path, first switching means and second switching means, And a controller for controlling the third switching means. The controller causes the cooling water to flow in the first flow path by the first switching means, causes the refrigerant to not flow in the second flow path by the second switching means, and the first branch by the third switching means. In a state in which the cooling water does not flow through the flow path, the first control mode in which the cooling water flowing through the first flow path and the working fluid are heat-exchanged to cool the working fluid, and the first switching means changes the first flow path. In the heat exchange section, the cooling water does not flow, the second switching means causes the refrigerant to flow in the second flow path, and the third switching means causes the cooling water to flow in the first branch flow path. It is possible to execute at least the second control mode in which heat is exchanged between the refrigerant and the cooling water to cool the refrigerant, while heat is exchanged between the refrigerant flowing in the second flow path and the working fluid to cool the working fluid. ing.

  This cooling device has a first control mode in which the working fluid is cooled using cooling water, and a second control mode in which the working fluid is cooled using refrigerant. In the first control mode in which the working fluid is cooled using the cooling water, the cooling water can be easily obtained from the piping in the factory, but it is difficult to adjust the cooling capacity. On the other hand, in the second control mode in which the working fluid is cooled using the refrigerant, power for circulating the refrigerant is required, but the cooling capacity can be easily adjusted. In this cooling device, by switching between the first control mode and the second control mode in accordance with the heat load of the processing machine and the environmental temperature, a period for eliminating the power for circulating the refrigerant can be obtained, and the operation can be performed with less energy. The fluid can be properly cooled. In the second control mode, since cooling water is used for cooling the refrigerant, heat generated when the refrigerant is cooled is prevented from being discharged into the factory. For this reason, it can suppress that the temperature in a factory rises.

The figure which shows typically the relationship between the machine tool installed in the factory, a cooling device, and the cooling water piping in a factory. The figure which shows the structure of a cooling device typically.

  The main features of the embodiments described below are listed. The technical elements described below are independent technical elements and exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Absent.

(Characteristic 1) In the cooling device disclosed in the present specification, the controller is in a state in which the cooling water flows through the first flow path by the first switching means, and the refrigerant flows in the second flow path by the second switching means. In addition, the cooling water flows through the first branch flow path by the third switching means, while the refrigerant and the cooling water are heat-exchanged in the heat exchange section to cool the refrigerant, while flowing through the first flow path. Cooling water and working fluid; The third control mode for cooling the working fluid by exchanging heat between the refrigerant flowing through the second flow path and the working fluid may be further executable. According to such a configuration, the working fluid can be cooled more appropriately according to the heat load of the processing machine.

(Characteristic 2) The cooling device disclosed in the present specification may further include a temperature sensor that measures the temperature of the working fluid. The controller may be in the first control mode when the temperature measured by the temperature sensor is equal to or lower than a predetermined value, and may be in the second control mode when the temperature measured by the temperature sensor exceeds a predetermined value. According to such a configuration, the first control mode and the second control mode can be appropriately switched according to the thermal load of the processing machine.

  A cooling device 10 according to an embodiment will be described with reference to the drawings. As shown in FIG. 1, the cooling device 10 is disposed adjacent to a machine tool 12 installed in a factory and connected to a cooling tower 34 installed outdoors via water pipes 30 and 32. Yes.

  The machine tool 12 is a machine for processing a workpiece into a part shape, and examples thereof include a cutting machine that performs cutting on the workpiece. The machine tool 12 and the cooling device 10 are connected by a supply channel 14 and a return channel 16. The working fluid (for example, cutting fluid, hydraulic oil, etc.) cooled by the cooling device 10 is supplied to the machine tool 12 through the supply channel 14. The working fluid supplied to the machine tool 12 cools a heated portion of the machine tool 12 (for example, a bearing portion that supports the main shaft of the machine tool 12). The working fluid whose temperature has been raised by cooling the heated portion is returned to the cooling device 10 through the return flow path 16. The working fluid returned from the return flow path 16 is cooled by the cooling device 10 and supplied to the machine tool 12 again.

  Cooling water cooled by the cooling tower 34 flows through the water pipe 30. A supply pipe 18 branches from the water pipe 30, and the end of the supply pipe 18 is connected to the cooling device 10. Therefore, the cooling water flowing through the water pipe 30 is supplied to the cooling device 10 through the supply pipe 18. The supply pipe 18 is provided with a thermometer 22 for measuring the temperature of the cooling water flowing in the supply pipe 18 and a strainer 24 for removing foreign substances from the cooling water flowing in the supply pipe 18. By providing the thermometer 22 in the supply pipe 18, the operator can check the temperature of the cooling water flowing in the supply pipe 18.

  The cooling device 10 is connected to the water pipe 32 by a return pipe 20. That is, the cooling water discharged from the cooling device 10 (cooling water whose water temperature has increased) flows to the water pipe 32 through the return pipe 20. The cooling water that has flowed to the water pipe 32 is returned to the cooling tower 34 through the water pipe 32 and cooled by the cooling tower 34. The return pipe 20 is provided with a flow meter 28 and a thermometer 26. For this reason, the operator can check the flow rate and temperature of the cooling water flowing through the return pipe 20.

  Next, the configuration of the cooling device 10 will be described in detail with reference to FIG. As shown in FIG. 2, the cooling device 10 includes a tank 40 that stores the working fluid, a main body 38 that cools the working fluid in the tank 40, and a controller 82 that controls the main body 38. A return flow path 16 is connected to the tank 40. The working fluid that has flowed from the machine tool 10 to the return flow path 16 is returned to the tank 40 and stored. The working fluid stored in the tank 40 is discharged to the supply flow path 14 by the pump 42. As a result, the working fluid is supplied from the supply flow path 14 to the machine tool 10. A temperature sensor 41 is disposed in the tank 40. The temperature sensor 41 detects the temperature of the working fluid stored in the tank 40. The temperature of the working fluid detected by the temperature sensor 41 is input to the controller 82.

  The main body 38 includes a first cooler 44 that cools the working fluid with cooling water, and a second cooler 60 that cools the working fluid with refrigerant. The first cooler 44 includes an inflow pipe 44, a heat exchange unit 48, and an outflow pipe 50. The supply pipe 18 is connected to one end 76 of the inflow pipe 44. The other end of the inflow pipe 44 is connected to the inflow end of the heat exchange unit 48. For this reason, the cooling water supplied from the supply pipe 18 flows through the inflow pipe 44 and is supplied to the heat exchange unit 48. The heat exchange unit 48 is formed by spirally forming a pipe through which cooling water flows, and is immersed in the working fluid in the tank 40. For this reason, the cooling water flowing through the heat exchanging section 48 and the working fluid stored in the tank 40 exchange heat, and the working fluid in the tank 40 is cooled. One end of the outflow pipe 50 is connected to the outflow end of the heat exchange unit 48. The other end 78 of the outflow pipe 50 is connected to the return pipe 20. Therefore, the cooling water flowing out from the heat exchange part 48 flows into the return pipe 20 through the outflow pipe 50. A control valve 52 is disposed on the outflow pipe 50. When the control valve 52 is opened, the cooling water flows through the inflow pipe 44, the heat exchange unit 48, and the outflow pipe 50. On the other hand, when the control valve 52 is closed, the cooling water does not flow through the inflow pipe 44, the heat exchange unit 48, and the outflow pipe 50. The controller 82 opens and closes the control valve 52.

  Note that one end of the bypass pipe 54 is connected to the inflow pipe 44, and the other end of the bypass pipe 54 is connected to the outflow pipe 50. The bypass pipe 54 is provided with a condenser 58 and a control valve 56 which will be described later. When the control valve 56 is opened, the cooling water flows through the bypass pipe 54. On the other hand, when the control valve 56 is closed, the cooling water does not flow through the bypass pipe 54. The controller 82 opens and closes the control valve 56. The other end of the bypass pipe 54 is connected to the outflow pipe 50 on the downstream side of the position where the control valve 52 is disposed. For this reason, even when the control valve 52 is closed, the control valve 56 can be opened to allow the cooling water to flow through the bypass passage 54.

  The second cooler 60 includes a compressor 62, a condenser 58, an expansion valve (or capillary or the like) 70, a heat exchange unit 66, and a receiver tank 64. These parts 62, 64, 66, 70 and 58 are connected by a pipe 68. The compressor 62 is a compressor that compresses the refrigerant, and is controlled by the controller 82. When the controller 82 turns on the compressor 62, the refrigerant compressed by the compressor 62 circulates in the pipe 68. When the controller 82 turns off the compressor 62, the refrigerant flow in the pipe 68 stops. The refrigerant compressed by the compressor 62 becomes a high-temperature and high-pressure gas and is sent to the condenser 58. The condenser 58 includes a cooling water channel 55 (a part of the bypass pipe 54) through which cooling water flows and a refrigerant channel 72 through which a refrigerant flows. For this reason, the refrigerant sent to the condenser 58 is cooled by exchanging heat with the cooling water flowing through the cooling water channel 55. The refrigerant cooled by the condenser 58 is decompressed by the expansion valve 70 and sent to the heat exchange unit 66. The heat exchange unit 66 is formed by spirally forming a pipe through which the refrigerant flows, and is immersed in the working fluid in the tank 40. For this reason, the refrigerant flowing through the heat exchange unit 66 and the working fluid stored in the tank 40 exchange heat, and the working fluid in the tank 40 is cooled. The refrigerant that has exchanged heat in the heat exchange unit 66 is stored in the receiver tank 64. The refrigerant stored in the receiver tank 64 is compressed again by the compressor 62 and circulates in the pipe 68.

  The main body 38 further includes a stirring blade 80 for stirring the working fluid stored in the tank 40 and a motor 74 that drives the stirring blade 80. The motor 74 is on / off controlled by the controller 82. When the motor 74 is turned on, the stirring blade 80 rotates. Thereby, the working fluid in the tank 40 is agitated, and the temperature of the working fluid in the tank 40 becomes uniform.

  The controller 82 is configured by a computer including a CPU, a ROM, a RAM, and the like. A temperature sensor 41, control valves 52 and 56, a compressor 62, and a motor 74 are connected to the controller 82. The controller 82 performs on / off control of the control valves 52 and 56 and on / off control of the compressor 62 based on the temperature of the working fluid in the tank 40 detected by the temperature sensor 41. Further, the controller 82 performs control to drive the motor 74 and rotate the stirring blade 80.

  Next, operation | movement of the cooling device 10 mentioned above is demonstrated. In the cooling device 10, the controller 82 switches the control mode according to the temperature detected by the temperature sensor 41 (the temperature of the working fluid stored in the tank 40). That is, (1) when the temperature detected by the temperature sensor 41 is less than the first set value, the working fluid is not cooled by the cooling water and the refrigerant, and (2) the temperature detected by the temperature sensor 41 is the first When the set value is not less than the set value and less than the second set value (> first set value), the working fluid is cooled with cooling water, and (3) the temperature detected by the temperature sensor 41 is not less than the second set value. In this case, the working fluid is cooled by the refrigerant. Hereinafter, the cases (1) to (3) will be described.

(1) When the temperature of the working fluid detected by the temperature sensor 41 is less than the first set value The controller 82 turns off the control valves 52 and 56 and turns off the compressor 62. As a result, the cooling water does not circulate in the first cooler 44, and the refrigerant does not circulate in the second cooler 60. For this reason, the working fluid in the tank 40 is not cooled, and the temperature of the working fluid rises according to the heat generated by the machine tool 12.

(2) When the temperature of the working fluid detected by the temperature sensor 41 is equal to or higher than the first set value and lower than the second set value, the controller 82 turns off the compressor 62 and turns on the control valve 52 to turn the outlet pipe 50 On the other hand, the control valve 56 is turned off and the bypass pipe 54 is closed. As a result, the cooling water from the supply pipe 18 flows through the inflow pipe 44 → the heat exchange section 48 → the outflow pipe 50 and is discharged to the return pipe 20. For this reason, the working fluid in the tank 40 is cooled by the cooling water flowing through the heat exchange unit 48. In addition, since the controller 82 is turning off the compressor 62, the refrigerant does not flow through the second cooler 60. For this reason, the working fluid in the tank 40 is cooled only by the cooling water.

(3) When the temperature of the working fluid detected by the temperature sensor 41 is equal to or higher than the second set value The controller 82 turns on the compressor 62 and turns off the control valve 52 to close the outflow pipe 50, while 56 is turned on and the bypass pipe 54 is opened. As a result, the refrigerant flows through the second cooler 60 and the cooling water flows through the bypass pipe 54. For this reason, the working fluid in the tank 40 is cooled by the refrigerant flowing in the second cooler 60, and the refrigerant flowing in the second cooler 60 is cooled by the cooling water flowing in the bypass pipe 54. At this time, the output of the compressor 62 is controlled by the controller 82, and the cooling capacity is adjusted according to the temperature of the working fluid.

  As described above, in the cooling device 10 of the present embodiment, the control mode for cooling the working fluid with the cooling water and the working fluid with the refrigerant are cooled according to the temperature of the working fluid used in the machine tool 12. Switch to control mode. For this reason, according to the heat load of the machine tool 12, the cooling capacity of the cooling device 10 can be switched appropriately. In addition, since the time for cooling the working fluid with the refrigerant is shortened, the time for driving the compressor 62 can be shortened. As a result, power saving of the cooling device 10 can be achieved, and the life of the compressor 62 can be extended.

  Further, since the cooling of the refrigerant in the second cooler 60 (cooling in the condenser 58) is performed by the cooling water flowing through the bypass pipe 54, the hot air generated when the refrigerant is cooled in the atmosphere is exhausted into the factory. Can be prevented. As a result, the operating time of the air conditioning equipment in the factory can be reduced, and energy saving can be achieved.

  Finally, the correspondence between the above-described embodiments and the claims will be described. Each flow path of the first cooler 44 is an example of “first flow path”, each flow path of the second cooler 60 is an example of “second flow path”, and the control valve 52 is “first flow path”. The compressor 62 is an example of a “second switching unit”, the bypass pipe 54 is an example of a “first branch passage”, and the control valve 56 is a “third switching unit”. The condenser 58 is an example of “a heat exchanging part that exchanges heat between the cooling water and the refrigerant”.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  For example, in the embodiment described above, the control mode is switched between the control mode in which the working fluid is cooled by the cooling water and the control mode in which the working fluid is cooled by the refrigerant. However, the control mode in which the working fluid is cooled by both the cooling water and the refrigerant. May be provided. By providing such a control mode, the working fluid can be cooled more precisely.

  Further, in the above-described embodiments, the cooling device cools the working fluid used in the machine tool. However, the cooling device disclosed in the present specification can be used for other purposes. For example, it can be used to cool a working fluid that cools a heat generating part (for example, a mold) of a press machine.

  Furthermore, in the above-described embodiments, the working fluid can be cooled by the refrigerant in various ways. For example, the main flow path through which the refrigerant flows may be branched, the refrigerant may flow through the branched branch flow path, and the working fluid may be cooled by the refrigerant flowing through the branch flow path. For example, when a large cooling capacity is required, the refrigerant may be flowed through both the main flow path and the branch flow path, and the working fluid may be cooled by the refrigerant flowing through these two flow paths. On the other hand, if a small cooling capacity is sufficient, the main flow path may be in a state where no refrigerant flows, while the branch flow path is in a state where refrigerant flows, and the working fluid may be cooled by the refrigerant flowing through the branch flow path.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

10: Cooling device 12: Machine tool 40: Tank 44: First cooler 60: Second cooler

Claims (4)

A cooling device for cooling a working fluid used in a processing machine,
A first flow path through which cooling water flows;
A first branch channel branched from the first channel;
A second flow path through which the refrigerant flows;
First switching means for switching between a state in which the cooling water flows in the first flow path and a state in which the cooling water does not flow;
Second switching means for switching between a state in which the refrigerant flows in the second flow path and a state in which the refrigerant does not flow;
Third switching means for switching between a state in which the cooling water flows in the first branch flow path and a state in which the cooling water does not flow;
A heat exchanging section for exchanging heat between the cooling water flowing through the first branch flow path and the refrigerant flowing through the second flow path;
A controller for controlling the first switching means, the second switching means, and the third switching means;
The controller
The first switching means causes the coolant to flow through the first flow path, the second switching means causes the coolant to not flow through the second flow path, and the third switching means causes the first branch flow path to enter the first flow path. A first control mode for cooling the working fluid by exchanging heat between the cooling water flowing through the first flow path and the working fluid as a state in which the cooling water does not flow;
Cooling water does not flow in the first flow path by the first switching means, refrigerant flows in the second flow path by the second switching means, and the first branch flow path is set by the third switching means. As the state in which the cooling water flows, the heat exchange unit heat-exchanges the refrigerant and the cooling water to cool the refrigerant, while the refrigerant flowing through the second flow path and the working fluid exchange heat to cool the working fluid. Two control modes;
A cooling device that is at least feasible. The controller
The first switching means causes the cooling water to flow through the first flow path, the second switching means causes the coolant to flow through the second flow path, and the third switching means cools the first branch flow path. As the state where water flows, the refrigerant and cooling water are heat-exchanged in the heat exchanging section to cool the refrigerant, while the cooling water and working fluid flowing through the first flow path and the refrigerant and operation flowing through the second flow path are operated. The cooling device according to claim 1, wherein the third control mode in which the working fluid is cooled by exchanging heat with the fluid is further executable. A temperature sensor for measuring the temperature of the working fluid;
3. The controller according to claim 1, wherein the controller is set to a first control mode when a temperature measured by the temperature sensor is equal to or lower than a predetermined value, and is set to a second control mode when the temperature measured by the temperature sensor exceeds a predetermined value. Cooling system. A temperature sensor for measuring the temperature of the working fluid;
The controller is set to a first control mode when a temperature measured by the temperature sensor is equal to or lower than a predetermined value, and is set to a second control mode or a third control mode when the temperature measured by the temperature sensor exceeds a predetermined value. 2. The cooling device according to 2.

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