JP2003172571A - Cooling water feeder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems that the vibration level of a compressor is increased attributable to the compression torque fluctuation in one rotation of the compressor when the rotational frequency of the compressor is low because the rotational frequency of the compressor is always fluctuated corresponding to the cooling load fluctuation in a convention cooling water feeder, and the compressor does not fully follow the cooling load fluctuation if the operation at a low speed is limited to avoid the vibration. <P>SOLUTION: The load following property is improved by reducing the vibration level of the compressor by fitting a plate-like mass to a lower part of the compressor constituting a refrigeration cycle, while the operation at a low speed is enabled. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention stabilizes the performance of a processing apparatus by supplying cooling water of a constant temperature to a thermal load section of a laser processing machine or the like to cool the thermal load section, and The present invention relates to a cooling water supply device that improves reliability.

[0002]

2. Description of the Related Art A laser processing machine has been remarkably popularized in recent years because it is relatively easy to adjust from a low energy density area to a high energy density area and can be processed at high speed without contact. Generally, in a laser processing machine, the load on the laser side greatly varies depending on the material, plate thickness, processing speed, processing shape, etc. of the non-processed object. Therefore, the cooling water supply device that cools the oscillation part of the laser beam machine is required to have cooling performance capable of following such cooling load fluctuations. A conventional cooling water supply device of this type is described in JP-A-11-305847 and is shown in FIG. In this conventional cooling water supply device, the rotational frequency of the compressor that constitutes the refrigeration cycle is variably controlled by the inverter to cope with the load fluctuation.

[0003]

In such a conventional cooling water supply apparatus, since the rotation frequency of the compressor constantly fluctuates in response to load variations, when the rotation frequency of the compressor becomes low, the compressor However, there is a problem that the vibration of the compressor is increased due to the fluctuation of the compression torque during one rotation. In particular, when a one-piston rotary compressor is used as the compressor, the torque fluctuation during one rotation is large, and the vibration during low-speed rotation becomes significantly large. As a result, the vibration of the cooling water supply device body also becomes large, and there is a problem that the laser beam machine is vibrated. Further, if the operation at low speed is limited to avoid vibration, there is a problem that it does not sufficiently follow the load fluctuation.

Recently, among laser processing machines,
Since the semiconductor laser has a high oscillation efficiency of 50%,
It is being adopted as an oscillation source for laser processing machines. Since the semiconductor laser has a high efficiency and a small heat loss, the cooling capacity of the cooling water supply device can be small. In order to reduce the size of the entire laser processing machine and make it easier to handle, it is required to store the semiconductor laser processing machine main body and the cooling water supply device in one rack. It will be especially necessary to deal with.

The present invention was devised in order to solve the above-mentioned conventional problems, and significantly reduces the vibration of the compressor, especially the vibration at low speed rotation, which results in a high load followability and a compact size. An object of the present invention is to provide a simple cooling water supply device.

[0006]

The present invention has been devised in order to solve the above-mentioned conventional problems. As a first means of the present invention, a compressor, a condenser and an evaporator are sequentially arranged. It has a refrigeration cycle connected by a refrigerant pipe, a cooling water cycle in which an evaporator, a water tank, a water pump, and a heat load are sequentially connected by a water pipe, and the cooling water whose temperature has risen is cooled by the evaporator. In a cooling water supply device that supplies cooling water having a substantially constant temperature in a water tank to a heat load with a water pump, a plate-shaped mass body is attached to a lower portion of a compressor.

As a second means of the present invention, a water pump, a water tank, or a lower part of the evaporator is provided with:
The mass body is arranged.

As a third means of the present invention, a refrigeration cycle in which a compressor, a condenser, and an evaporator are sequentially connected by a refrigerant pipe, an evaporator, a water tank, a water pump, and a heat load are provided. Equipped with a cooling water cycle that is sequentially connected by water pipes, the cooling water whose temperature has risen is cooled by an evaporator, and the cooling water that has reached a substantially constant temperature in the water tank is supplied to the heat load by a water pump. It is a device, and in this refrigeration cycle
In addition to using the HFC refrigerant, oil that is incompatible with the HFC refrigerant is used as refrigerating machine oil for the compressor.

Further, as a fourth means of the present invention, in the above cooling water supply device, R407C is used as the HFC refrigerant, and HAB oil is used as the refrigerating machine oil.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION According to the first means, a plate-like mass is attached to the lower portion of the compressor which constitutes the refrigeration cycle of the cooling water supply device, whereby the vertical axis (Z
The moment of inertia about the axis can be increased. Generally, the vibration of the compressor, especially the vibration around the Z-axis, becomes significantly large due to the fluctuation of the compression torque during one rotation at low speed rotation. Therefore, when the inertia moment is increased, the vibration around the Z axis is reduced in inverse proportion to this. As a result, the compressor can be operated in a low rotation speed range, and the load following performance is improved from a small heat load to a large heat load. Further, the vibration of the entire device can be suppressed to a small level.

According to the second means, in addition to the first means, the mass body is arranged in the lower part of either the water pump, the water tank, or the evaporator. The thin plate-shaped mass body does not get in the way, and the space can be effectively used. As a result, a compact cooling water supply device is obtained.

According to the third and fourth means, the HFC refrigerant is used in the refrigeration cycle of the cooling water supply device, and the oil that is incompatible with the HFC refrigerant is used as the refrigerating machine oil of the compressor. Therefore, the refrigerant hardly dissolves in the oil in the compressor. As a result, the amount of refrigerant sealed in the refrigeration cycle can be reduced. Further, even when the engine is stopped, the oil does not dissolve in the refrigerant in the compressor, so that the refrigerant quickly circulates in the refrigeration cycle at the time of start-up, the start-up becomes faster, and the load followability of the cooling water supply device becomes higher.

[0013]

EXAMPLES A cooling water supply device according to the present invention will be described based on examples. First, the contents according to claim 1 will be described. In the cooling water supply device shown in FIG. 1, 1 is a compressor, 2 is an outdoor heat exchanger, 3 is an outdoor fan, 4 is a decompression device, 5 is an evaporator, and these are sequentially connected by a refrigerant pipe 6. It constitutes a refrigeration cycle. On the other hand, 7 is a water pump, 8 is a filter, 9 is a water tank, 10 is a flow rate adjusting valve, 11 is an ion exchange resin, 12 is an electric heater installed in the water tank 9, and 13 is a heat load to be cooled ( For example, a laser oscillator). Further, the evaporator 5, the water tank 9, the water pump 7, the filter 8, the heat load 13, and the ion exchange resin 11 are connected by a water pipe 14 as shown in FIG. 1 to form a water cycle. Reference numeral 15 is an elongated plate-shaped mass body attached to the legs of the compressor 1.

The operation of this apparatus will be described. The water flowing through the water cycle is cooled in the evaporator 5 of the refrigeration cycle.
In the water cycle, the water pump 7 pumps the water in the water tank 9 to the heat load 13 to cool the heat load 13. As a result, the heat load, for example, the laser oscillating portion is cooled and maintained at a substantially constant temperature, whereby the laser output is stabilized and the laser oscillating portion is protected. The water warmed by passing through the heat load 13 is cooled by the evaporator 5 to lower its temperature, and then returns to the water tank 9. An electric heater is arranged in the water tank 9. The electric heater 9 operates when the temperature of the water in the water tank 9 becomes too low, and serves to keep the water temperature constant.

In the laser processing machine, the amount of heat to be removed by the heat load 13 greatly varies depending on the material, plate thickness, processing speed, processing shape and the like of the non-workpiece. Therefore, a cooling water supply device that cools such a heat load 13 is required to have cooling performance that follows such a load change. For that purpose, the rotation frequency of the compressor 1 must be changed rapidly from low speed to high speed. Generally, when the rotation frequency of the compressor becomes low, the vibration of the compressor becomes large due to the fluctuation of the compression torque during one rotation of the compressor. In particular, when a one-piston rotary compressor is used as the compressor, the torque fluctuation during one rotation is large, and the vibration during low-speed rotation becomes significantly large. When the amount of cooling heat of No. 13 was small, it could not be sufficiently followed, and there was a problem that the temperature of the cooling water was lowered more than necessary. In this embodiment, since the thin plate-shaped mass body 15 is attached to the compressor 1, this increases the moment of inertia about the z axis of the entire compressor, and as a result, the vibration of the compressor 1 is significantly reduced. . The vibration Θ about the z axis is determined by the following equation. (I1 + I2) -Θ = Tm-Tg I1; Inertia moment I2 of compressor 1; Inertia moment of mass body Θ; Rotational angular acceleration Tm of system as a whole; Rotational torque Tg of motor; Gas compression torque Moment of inertia (I1 + I2)
It can be seen that the vibration Θ decreases in inverse proportion to this as the value increases. The moment of inertia of the mass body is I 2 =
Since it is represented by ∫r2 · dm, it is possible to obtain a large moment of inertia with a small mass by making it into an elongated plate shape.

FIG. 2 shows vibration measurement values of the one-piston rotary compressor about the z-axis. In FIG. 2, the case where the mass body 15 is added and the case where the mass body 15 is not added are shown for comparison. As shown in FIG. 2, by mounting the mass body 15, vibration is significantly reduced from the low speed rotation speed range to the high speed rotation speed range. In particular, the effect of reducing vibration in the low speed rotation range is remarkable. Therefore, even when a low-priced compressor such as a one-piston rotary compressor, which has a large fluctuation in compression torque during one rotation, is used as the compressor, vibration at low speed rotation is suppressed by such a simple configuration. Therefore, it is possible to operate in a wide range from the low speed rotation range to the high speed rotation range. as a result,
The cooling water supply device can quickly cope with the load fluctuation of the heat load 13 and has a high load following property. Further, since the load followability of the refrigeration cycle is increased, the frequency of using the electric heater 12 is reduced, and the energy saving effect is produced.

Next, FIG. 3 shows an embodiment according to claim 2. FIG. 3 is a perspective view of the cooling water supply device, but the basic refrigeration cycle configuration and water cycle configuration are shown in FIG.
It is the same as the configuration shown in. In this embodiment, first, the water pump 7 is installed on the pump base 16, and then the elongated plate-shaped mass body 15 attached to the leg of the compressor 1 is attached to the pump base 1.
It is installed below 6. The mass body 15 has an elongated shape in terms of its function, but by installing the mass body 15 below the pump base 16 as described above, there is no obstruction to the installation of other parts, and space saving is achieved while maintaining the vibration reduction effect. Can be realized. That is, the mass body 1 for vibration reduction
Even if 5 is added, the cooling water cooling device does not become large. In FIG. 3, the vibration-reducing mass body 15 is installed below the water pump 7, but the same effect as described above can be obtained even if the mass body 15 is installed below the water tank 9 or the evaporator 5.

Next, the contents relating to claims 3 and 4 will be described. HF is used for the refrigeration cycle of the cooling water supply device shown in FIG.
C refrigerant is used, and H is used as refrigerating machine oil for the compressor 1.
Oil that is incompatible with FC refrigerant is used. By selecting such a combination of refrigerant and oil, the compressor 1
During the operation of, the refrigerant hardly dissolves in the oil. As a result, it is possible to obtain the effect of reducing the amount of refrigerant enclosed in the refrigeration cycle. In addition, even when the compressor stops, the amount of oil that dissolves in the refrigerant in the compressor is small, so the refrigerant circulates quickly in the refrigeration cycle at startup, the start-up of the refrigeration cycle becomes faster, and the load following of the cooling water supply device follows. It is possible to obtain the effect of increasing the property.

Further, R407C is used as the HFC refrigerant, and R407C is used.
HAB oil is selected as an oil that does not mix with C. R4
The refrigerating capacity per unit volume of 07C is about 1.5 times higher than that of R134a, which is an HFC refrigerant, which allows the compressor 1, condenser 2 and evaporator 5 to be made compact and the entire cooling device. The effect of being able to miniaturize is obtained. As a result, the cooling water cooling device can be integrated into a size that can be stored in a rack, and a device that is easy to handle can be provided. Further, HAB oil is incompatible with R407C and has the advantage of being inexpensive, so that the device can be provided at low cost.

[0020]

As an effect of the first means, by attaching a plate-like mass body to the lower portion of the compressor,
Increase the moment of inertia about the vertical axis of the compressor,
The vibration of the compressor decreases in inverse proportion to this moment of inertia. As a result, the compressor can be operated in a low rotational speed range, and the cooling water supply device has a high load followability from a small heat load to a large heat load. Further, the vibration of the entire device can be suppressed to a small level.

The effect of the second means is that, in addition to the effect of the first means, the mass body is arranged in the lower part of either the water pump, the water tank, or the evaporator. Therefore, the thin plate-shaped mass body does not get in the way, and the space can be effectively used, and as a result, a compact cooling water supply device can be realized.

As an effect of the third means, the HFC refrigerant is used in the refrigerating cycle, and the refrigerating machine oil is incompatible with the HFC refrigerant. Hardly dissolves in oil.
As a result, the amount of refrigerant sealed in the refrigeration cycle can be reduced. Further, even when the engine is stopped, the oil does not dissolve in the refrigerant in the compressor, so that the refrigerant quickly circulates in the refrigeration cycle at the time of start-up, the start-up becomes faster, and the load followability of the cooling water supply device becomes higher.

The effect of the fourth means is that R407C is used as the HFC refrigerant and HAB oil is selected as the oil that is incompatible with R407C, so that the refrigerating capacity is about the same as when R134a is used. Since this is 1.5 times as high, it is possible to obtain an effect that the compressor, the condenser, and the evaporator can all be made compact, and the entire apparatus can be made compact. Furthermore, by using HAB oil as an incompatible oil, an effect that an inexpensive device can be provided can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a cooling water supply device according to the present invention.

FIG. 2 is a diagram showing a vibration reducing effect of the present invention.

FIG. 3 is a diagram showing an embodiment of a cooling water supply device according to the second claim of the present invention.

FIG. 4 is a view showing a conventional cooling water supply device.

[Explanation of symbols]

1 compressor 2 condenser 5 evaporator 7 water pump 9 water tank 13 heat load

Continued front page    (72) Inventor Akira Fujitaka             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Yasuto Mukai             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd.

Claims (4)

[Claims] 1. A refrigeration cycle in which a compressor, a condenser, and an evaporator are sequentially connected by a refrigerant pipe, and a cooling in which the evaporator, a water tank, a water pump, and a heat load are sequentially connected by a water pipe. A cooling water supply device comprising a water cycle, cooling the temperature-increased cooling water by the evaporator, and supplying the cooling water having a substantially constant temperature in the water tank to the heat load by the water pump, A cooling water supply device in which a plate-shaped mass body is attached to a lower portion of the compressor. 2. The cooling water supply device according to claim 1, wherein the mass body is arranged in a lower portion of any one of the water pump, the water tank, and the evaporator. 3. A refrigeration cycle in which a compressor, a condenser, and an evaporator are sequentially connected by a refrigerant pipe, and a cooling in which the evaporator, a water tank, a water pump, and a heat load are sequentially connected by a water pipe. A cooling water supply device comprising a water cycle, cooling the temperature-increased cooling water by the evaporator, and supplying the cooling water having a substantially constant temperature in the water tank to the heat load by the water pump, A cooling water supply device that uses an HFC refrigerant in the refrigeration cycle and uses, as refrigerating machine oil for the compressor, an oil that is incompatible with the HFC refrigerant. 4. The cooling water supply device according to claim 3, wherein R407C is used as the HFC refrigerant, and HAB oil is used as the refrigerating machine oil.