JPS6216776B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-shaft cooling device that cools bearing parts such as a plurality of main shafts of a machine tool, for example.

Conventionally, there have been devices of this type as shown in FIGS. 1 and 2. In each of these figures, 1, 1
Reference numeral 1 denotes first and second spindle devices of the machine tool, which are arranged at an interval of span P. 2, 21 are main shafts, 3, 31 are bearings, 4, 41 are bearing stands, 5, 5
1 is a pulley and 6 is a bed.

Next, the operation will be explained. The main shafts 2, 21 are rotated by the rotational force transmitted to the pulleys 5, 51 via the V-belt by a driving electric motor (not shown). At this time, the bearings 3, 31 located between the main shafts 2, 21 and the bearing stands 4, 41 have the purpose of helping the main shafts 2, 21 rotate smoothly.
As the bearings 3 and 31 rotate, they generate heat due to friction and their temperature increases. The amount of heat generated in the bearings 3, 31 is transmitted to the bearing stands 4, 41, and is transferred to the bed 6 and the surrounding air to radiate heat. At this time, the temperature of the bearing stands 4 and 41 increases, and various thermal deformations and strains occur in each part due to thermal expansion. For this reason, the positions of the main shafts 2 and 21 fluctuate,
There was a drawback that the machining accuracy decreased when machining the workpiece. Furthermore, there is a drawback that there is a difference in the fluctuation of the positions of the main shafts 2 and 21 between them, and at the same time, there is a difference in the machining accuracy when performing a plurality of machining operations.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and an object of the present invention is to provide a multi-shaft cooling device that can effectively and evenly cool the first and second main shaft devices. It is an object.

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. FIG. 3 is a block diagram showing the functional system, and FIG. 4 is a cross-sectional side view. In each of these figures, 7 and 71 are annular hollow chambers formed inside the bearing stands 4 and 41, and 8 and 81 are annular hollow chambers formed inside the bearing stands 4 and 41. It is a heat dissipation device and is cooled by cooling fans 9 and 91. 10, 101 are steam pipes communicating the hollow chambers 7, 71 and the heat radiating devices 8, 81, respectively; 12, 12;
Reference numeral 1 designates liquid pipes that communicate the hollow chambers 7, 71 and the heat radiating devices 8, 81, respectively. 13 is a first communication pipe that communicates between the steam pipe 10 and the heat radiating device 81 and has a flexible part 13a such as a bellows, which can be expanded and contracted; This is a second communication pipe having a flexible part 131a that can be expanded and contracted.

In addition, the hollow chambers 7, 71 and the heat dissipation devices 8, 81,
After reducing the pressure inside the steam pipes 10, 101 and liquid pipes 12, 121, a predetermined amount of a working liquid such as ammonia or fluorocarbon is sealed inside them.

Next, the operation will be explained. The heat of the bearings 3, 31 received by the bearing stands 4, 41 is taken away as latent heat of vaporization when the working liquid such as fluorocarbons in the hollow chambers 7, 71 is heated and vaporized, and the vapor of the vaporized fluorocarbons is Using the steam pressure, the steam is transferred through the steam pipes 10, 101 to the heat dissipation devices 8, 81, and the cooling fans 9,
91 to be cooled by ambient air. At this time, the vapor of fluorocarbon or the like is condensed and becomes a liquid, but the latent heat of condensation is released to the surrounding air, and the amount of heat from the bearings 3 and 31 is radiated to the surrounding air. The condensed working liquid passes through the liquid pipes 12 and 121 and is transferred to the bearing stands 4 and 4 using gravity.
Return to hollow chambers 7 and 71 in No. 1. Further, a part of the vapor of the working liquid passing through the steam pipe 10 flows into the heat radiating device 81 via the first communication pipe 13 , and the working liquid condensed and liquefied in the heat radiating device 81 passes through the liquid pipe 121 and flows into the bearing stand 41 . It flows into the hollow chamber 71. On the other hand, steam pipe 10
A part of the vapor of the working liquid passing through the second communication pipe 1
31 into the heat dissipation device 8, and the heat dissipation device 8
The condensed and liquefied working liquid flows into the hollow chamber 7 of the bearing pedestal 4 through the liquid pipe 12. By repeating such an operation, the amount of heat in the bearing stands 4, 41 is transported to the heat radiating devices 8, 81 and efficiently cooled.

By the way, if the temperature rise (calorific value) of the bearing pedestal 4 is greater than that of the other bearing pedestal 41, the amount of steam, pressure, and temperature during vaporization of the working liquid in the hollow chamber 7 of the bearing pedestal 4 will be greater than that of the other bearing pedestal. Become. Therefore, a larger amount of latent heat of vaporization is removed to cool the bearing pedestal 4 to a greater extent, and a larger amount of heat is transferred from the hollow chamber 7 of the bearing pedestal 4 not only to the heat radiating device 8 but also to the other heat radiating device 81 via the first communication pipe 13. Steam with high pressure and temperature flows in. As a result, when viewed from the bearing stand 4 side, the heat radiation area increases by the amount that flows into the other heat radiation device 81 via the first communication pipe 13, and the cooling capacity increases.
In addition, in the heat dissipation device 81 , high temperature steam flowing from the hollow chamber 7 of the bearing stand 4 flows into the hollow chamber 71 of the bearing stand 41 .
It mixes with the lower temperature steam that has flowed in, and as a result, the temperature of the steam that has flowed in from the hollow chamber 71 of the bearing stand 41 becomes higher. Therefore, the temperature of the working liquid condensed and liquefied in the heat dissipation device 81 also increases, and the temperature rise of the bearing stand 41 increases by the increased temperature. On the other hand, the second communication pipe 13 is connected not only to the heat radiating device 81 but also to the other heat radiating device 8 from the hollow chamber 71 of the bearing stand 41.
1, low temperature steam flows in, and mixes with high temperature steam flowing in from the hollow chamber 7 of the bearing pedestal 4 in the heat dissipation device 8, and as a result, the temperature of the steam flowing from the hollow chamber 7 of the bearing pedestal 4 is low. Become. Therefore, the temperature of the working liquid condensed and liquefied in the heat dissipation device 8 is also lowered.
The temperature rise of the bearing pedestal 4 is reduced by that amount.

By repeating these actions,
When the calorific value and temperature rise of either of the two bearing stands 4, 41 starts to increase, the difference in temperature rise between the two bearing stands 4, 41 is kept small, and the two bearing stands 4,
41 are effectively cooled on average. Therefore, in the machine tool, thermal deformation and distortion of the bearing portion can be minimized, and machining accuracy can be improved. Further, the span P between the main shaft 2 and the main shaft 21 can be made variable within the range of expansion and contraction of the flexible portions 13a and 131a of the first and second communication pipes 13 and 131.

In addition, although the case where the cooling fans 9, 91 were used in the above embodiment was described, the cooling fans 9, 91
A similar effect can be obtained by performing natural air cooling without using cooling air, or by using cooling water, oil, etc. other than cooling air as a cooling source.

Further, in the above embodiment, the flexible portion 13a,
Although the case where 131a is constituted by a bellows has been described, a flexible part which can be expanded and contracted may be constituted by a material other than the bellows.

Further, in the above embodiment, the hollow chambers 7 and 71 are provided in the bearing pedestals 4 and 41, respectively. You can also do this.

Incidentally, in the above description, the case where there are two spindle devices has been described, but the present invention can also be applied to a case where there are three or more spindle devices, and the same effects as in the above embodiment can be obtained.

As explained above, the present invention includes an annular hollow chamber formed inside a bearing portion and filled with a working liquid, and a heat dissipation device communicated with the hollow chamber through piping constituted by a steam pipe and a liquid pipe. The first and second spindle devices, the first
A first communication pipe that communicates the steam pipe of the main shaft device with the heat radiating device of the second main shaft device and has an expandable and contractible flexible part, the steam pipe of the second main shaft device and the heat radiating device of the first main shaft device. Provide a communication pipe having a flexible part that can be expanded and contracted and that communicates with the
By transporting the heat of the bearing part from the hollow chamber to the heat dissipation device, the heat of the bearing part can be quickly removed and cooled efficiently and evenly, minimizing thermal deformation and distortion of the bearing part. This has an extremely large practical effect in that it can improve the machining accuracy of machine tools, etc.

[Brief explanation of the drawing]

1 and 2 are cross-sectional side views showing a conventional multi-shaft cooling device, and FIGS. 3 and 4 are a block diagram and a cross-sectional side view showing a multi-shaft cooling device according to an embodiment of the present invention. In the figure, 1 and 11 are the first and second spindle devices, 4 and 41 are bearing stands, 7 and 71 are hollow chambers, 8,
81 is a heat dissipation device, 10, 12 and 101, 12
1 is a pipe, 13, 131 is a first and second communication pipe,
13a and 131a are flexible parts. still,
The same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. An annular hollow chamber formed inside the bearing portion and filled with a working liquid, and a heat dissipation device communicated with the hollow chamber through piping constituted by a steam pipe and a liquid pipe, respectively. a first and a second main spindle device mounted on the same machine; a second main spindle device that communicates the steam pipe of the first main spindle device with a heat dissipation device of the second main spindle device and has an expandable and contractible flexible portion; 1 communication pipe, the steam pipe of the second main shaft device and the first
A second communication pipe is provided which communicates with the heat radiating device of the main shaft device and has an expandable and contractible flexible portion, and the heat of the bearing portion is transferred from the hollow chamber to the heat radiating device by the evaporation and condensation action of the working liquid. A multi-axis cooling device characterized by being adapted to be transported. 2. The multi-axis cooling device according to claim 1, wherein the hollow chamber is formed in a bearing stand. 3. The multi-shaft cooling device according to claim 1, wherein the hollow chamber is formed between the bearing stand and the bearing. 4. The multi-axis cooling device according to any one of claims 1 to 3, characterized in that the flexible portion is constituted by a bellows.