Temperature control device

Abstract

To provide a temperature control device that can sufficiently cool a spindle unit.SOLUTION: A temperature control device 2 comprises: temperature adjusting means 14 that adjusts a temperature of liquid to a predetermined temperature; pressure-feeding means 16 that pressure-feeds liquid; a first temperature sensor 18 arranged at an inlet port 8a side of a flow path 8; a second temperature sensor 20 arranged at an outlet port 8b side of the flow path 8; and control means 22. The control means 22 controls the temperature adjusting means 14 so that a temperature detected by the second temperature sensor 20 is equal to a desired temperature and also controls the pressure-feeding means 16 so that a temperature difference between the temperature detected by the first temperature sensor 18 and the temperature detected by the second temperature sensor 20 is equal to a predetermined value.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a temperature control device that controls the temperature of a spindle unit that includes a spindle on which a tool is attached, a housing that rotatably supports the spindle, and a flow passage having an inlet and an outlet formed in the housing. [Background technology]

[0002] A wafer has a number of devices such as ICs and LSIs formed on its surface, separated by planned dividing lines. The back side of the wafer is ground by a grinding machine to a specified thickness, and the wafer is then divided into individual device chips by a dicing machine. Each of the divided device chips is used in electrical equipment such as mobile phones and personal computers.

[0003] The grinding device is generally composed of a chuck table for holding the wafer, a grinding means having a rotatably mounted grinding wheel with an annular grinding stone for grinding the wafer held on the chuck table, a grinding water supplying means for supplying grinding water (pure water) to the grinding wheel, and a cleaning means for cleaning the wafer, and is capable of grinding the wafer with high precision (see, for example, Patent Document 1).

[0004] The dicing device is generally composed of a chuck table that holds the wafer, cutting means with a rotatably mounted cutting blade that cuts the wafer held on the chuck table, cutting water supply means that supplies cutting water (pure water) to the cutting blade, and cleaning means that cleans the wafer, and can divide the wafer into individual device chips with high precision (see, for example, Patent Document 2).

[0005] The spindle units of the grinding means and cutting means may be subject to thermal distortion due to heat generation. If thermal distortion occurs in the spindle unit, high-precision machining cannot be maintained. Therefore, a temperature control device is used to control the spindle unit to reduce the effects of thermal distortion. In the temperature control device, liquid (pure water) adjusted to a constant temperature is introduced into a flow path disposed inside the spindle unit to cool the spindle unit. In this case, the temperature control device measures the temperature of the liquid introduced into the flow path and the temperature of the liquid flowing out of the flow path, and adjusts the flow rate of the liquid introduced into the flow path so that the temperature difference between these temperatures is reduced (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2009-158768 A [Patent Document 2] JP 2019-145583 A [Patent Document 3] Patent Publication No. 2022-155306 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when the grinding load or cutting load varies relatively greatly depending on the type of workpiece, the flow rate to be fed into the flow passage of the spindle unit may exceed the allowable value (maximum value) of the flow rate that can be supplied from the temperature control device, causing a problem that the spindle unit cannot be sufficiently cooled.

[0008] An object of the present invention is to provide a temperature control device capable of sufficiently cooling a spindle unit. [Means for solving the problem]

[0009] According to the present invention, there is provided the following temperature control device that solves the above problems. "A temperature control device for controlling the temperature of a spindle unit including a spindle on which a tool is attached, a housing for rotatably supporting the spindle, and a flow passage having an inlet and an outlet formed in the housing, The liquid supply system comprises a temperature adjusting means for adjusting the temperature of the liquid to a predetermined temperature, a pumping means for pumping the liquid, a first temperature sensor disposed on the inlet side of the flow path, a second temperature sensor disposed on the outlet side of the flow path, and a control means; The control means controls the temperature adjustment means so that the temperature detected by the second temperature sensor becomes a desired temperature, and controls the pumping means so that the temperature difference between the temperatures detected by the first temperature sensor and the second temperature sensor becomes a predetermined value. Effect of the Invention

[0010] The temperature control device of the present invention comprises: A temperature control device for controlling a temperature of a spindle unit including a spindle on which a tool is attached, a housing for rotatably supporting the spindle, and a flow passage having an inlet and an outlet formed in the housing, The liquid supply system comprises a temperature adjusting means for adjusting the temperature of the liquid to a predetermined temperature, a pumping means for pumping the liquid, a first temperature sensor disposed on the inlet side of the flow path, a second temperature sensor disposed on the outlet side of the flow path, and a control means; The control means controls the temperature adjustment means so that the temperature detected by the second temperature sensor becomes a desired temperature, and also controls the pumping means so that the temperature difference between the temperatures detected by the first temperature sensor and the second temperature sensor becomes a predetermined value, so that the temperature of the spindle unit can be stably controlled by measuring the temperature of the liquid at the outlet side of the flow path and controlling the temperature adjustment means so that the temperature at the outlet side becomes a desired temperature. Furthermore, in the present invention, the spindle unit can be always maintained at a constant temperature by controlling the pumping means so that the temperature difference between the liquid temperature at the inlet side of the flow path and the liquid temperature at the outlet side of the flow path becomes a predetermined value. Therefore, according to the present invention, the spindle unit can be sufficiently cooled. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a circuit diagram of a temperature control device according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a temperature control device according to the present invention will be described with reference to the drawings.

[0013] (Temperature control device 2) The temperature control device 2 shown in FIG. 1 controls the temperature of a spindle unit 4 mounted on a processing device such as a grinding device or a dicing device. The spindle unit 4 includes a spindle (not shown) on which a tool is mounted, a housing 6 that rotatably supports the spindle, and a flow path 8 having an inlet 8a and an outlet 8b formed in the housing 6. The inlet 8a of the flow path 8 is connected to the temperature control device 2 by a first pipeline 10, and the outlet 8b of the flow path 8 is connected to the temperature control device 2 by a second pipeline 12. When the spindle unit 4 is a grinding device, a grinding wheel having an annular grinding stone for grinding a workpiece is mounted on the spindle as a tool. When the spindle unit 4 is a dicing device, a cutting blade for cutting a wafer is mounted on the spindle as a tool.

[0014] As shown in FIG. 1, the temperature control device 2 includes a temperature adjustment means 14 for adjusting a liquid such as pure water to a predetermined temperature, a pumping means 16 for pumping the liquid, a first temperature sensor 18 disposed on the inlet 8a side of the flow path 8, a second temperature sensor 20 disposed on the outlet 8b side of the flow path 8, and a control means 22.

[0015] (Temperature adjustment means 14) The temperature adjustment means 14 cools or heats the liquid to adjust the temperature of the liquid to a predetermined temperature by performing heat exchange between the liquid passing through the temperature adjustment means 14 and the refrigerant circulating through the temperature adjustment means 14. The liquid adjusted to the predetermined temperature by the temperature adjustment means 14 is supplied to the inlet 8a of the flow path 8 via the first pipe 10.

[0016] Although not shown, the temperature adjustment means 14 may be configured to include a compressor that compresses the refrigerant, a condenser that condenses the refrigerant compressed by the compressor, a variable expansion valve that expands the refrigerant condensed by the condenser, and an evaporator that vaporizes the expanded refrigerant. The compressor motor that drives the compressor is provided with an inverter that changes the frequency of the power supplied to the compressor motor within a predetermined range. Therefore, the inverter changes the rotation speed of the compressor motor and changes the rotation speed of the compressor within a predetermined range.

[0017] (Pumping means 16) The pumping means 16 sucks in and pumps the liquid that has flowed out from the outlet 8b of the flow path 8 to the second pipeline 12. The liquid pumped from the pumping means 16 is sent to the inlet 8a of the flow path 8 via the third pipeline 24, the temperature adjustment means 14, and the first pipeline 10. The pumping means 16 may include a pump, a pump motor that drives the pump, and an inverter that changes the frequency of the power supplied to the pump motor. In the pumping means 16, the inverter can change the rotation speed of the pump within a predetermined range.

[0018] (First and second temperature sensors 18, 20) The first temperature sensor 18 is provided in the first pipeline 10 and detects the temperature of the liquid sent from the temperature adjustment means 14 to the inlet 8a of the flow path 8. The second temperature sensor 20 is provided in the second pipeline 12 and detects the temperature of the liquid sent from the outlet 8b of the flow path 8 to the pumping means 16. The temperatures detected by the first and second temperature sensors 18, 20 are sent to the control means 22.

[0019] (Control means 22) The control means 22 controls the operations of the temperature adjustment means 14 and the liquid feeding means 16 based on the temperatures detected by the first and second temperature sensors 18 and 20. The control means 22 controls the rotational speed of the compressor by sending a signal to the inverter of the compressor motor with respect to the temperature adjustment means 14, and adjusts the opening degree of the variable expansion valve by sending a signal to the actuator of the variable expansion valve. In this way, the control means 22 controls the cooling amount or heating amount of the liquid by the temperature adjustment means 14. Further, the control means 22 controls the flow rate of the liquid sent out from the liquid feeding means 16 by sending a signal to the inverter of the pump motor with respect to the liquid feeding means 16 to control the rotational speed of the pump. Such control means 22 can be constituted by a computer having a processor and a memory.

[0020] Next, the operation of the temperature control device 2 described above will be explained.

[0021] When the required processing is performed by the processing device on which the spindle unit 4 is mounted, an operation start instruction is input to the control means 22 of the temperature control device 2. Then, the control means 22 circulates the liquid between the temperature control device 2 and the housing 6 of the spindle unit 4 by operating the temperature adjustment means 14 and the liquid feeding means 16.

[0022] When circulating the liquid, the control means 22 controls the temperature adjustment means 14 so that the temperature detected by the second temperature sensor 20 becomes the desired temperature. That is, the control means 22 controls the temperature adjustment means 14 so that the temperature on the outlet 8b side becomes the desired temperature (for example, about 20°C) even if the load of the spindle unit 4 changes. For this reason, even if the load of the spindle unit 4 changes, the temperature of the spindle unit 4 can be stably controlled. Note that the control means 22 controls the cooling amount or heating amount of the liquid by the temperature adjustment means 14 by adjusting the rotational speed of the compressor and the opening degree of the variable expansion valve.

[0023] Moreover, the control means 22 controls the pressure-feeding means 16 so that the temperature difference between the temperature detected by the first temperature sensor 18 and the temperature detected by the second temperature sensor 20 becomes a predetermined value. As described above, the control means 22 controls the temperature adjustment means 14 so that the temperature on the outlet 8b side becomes a desired temperature. Therefore, the control means 22 of this embodiment controls the temperature on the outlet 8b side to a desired temperature by the temperature adjustment means 14, and controls the temperature on the inlet 8a side to a desired temperature by the pressure-feeding means 16 so that the temperature difference with the temperature on the outlet 8b side becomes a predetermined value. In short, in this embodiment, the temperatures on the inlet 8a side and the outlet 8b side are each controlled to a desired temperature. As a result, the temperature of the spindle unit 4 is always maintained at a constant temperature.

[0024] In this manner, in the temperature control device 2 of this embodiment, the temperature adjustment means 14 is controlled so that the temperature detected by the second temperature sensor 20 becomes a desired temperature, and the pressure-feeding means 16 is controlled so that the temperature difference between the temperature detected by the first temperature sensor 18 and the temperature detected by the second temperature sensor 20 becomes a predetermined value. Therefore, according to the temperature control device 2 of this embodiment, it is possible to sufficiently cool the spindle unit 4. [Explanation of symbols]

[0025] 2: Temperature control device 4: Spindle unit 6: Housing 8: Flow path 8a: Entrance of the flow channel 8b: Outlet of the flow channel 10: First Pipeline 12: Second pipeline 14: Temperature adjustment means 16: Pressure feeding means 18: First temperature sensor 20: Second temperature sensor 22: Control means 24: The third pipeline

Claims

[Claim 1] A temperature control device for controlling a temperature of a spindle unit including a spindle on which a tool is attached, a housing for rotatably supporting the spindle, and a flow passage having an inlet and an outlet formed in the housing, The liquid supply system comprises a temperature adjusting means for adjusting the temperature of the liquid to a predetermined temperature, a pumping means for pumping the liquid, a first temperature sensor disposed on the inlet side of the flow path, a second temperature sensor disposed on the outlet side of the flow path, and a control means; The control means controls the temperature adjustment means so that the temperature detected by the second temperature sensor becomes a desired temperature, and controls the pumping means so that the temperature difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor becomes a predetermined value.

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