JP2594070Y2 - Spindle motor cooling device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle motor cooling device provided with radial and thrust hydrostatic bearings.

[0002]

2. Description of the Related Art Conventionally, a spindle motor for fixing a tool to the tip of a spindle to perform small-diameter hole drilling, dicing, slicing, etc., needs to rotate at high speed. Static pressure bearing. In order to maintain processing accuracy,
For example, as shown in FIGS. 3 and 4A and 4B,
A stator 2 is provided inside a hollow cylindrical frame 1, and a spindle 3 is provided inside the stator 2 so as to be rotatable through an air gap. The rotor 4 is fixed. A thrust receiving disk 31 is provided on the distal end side of the spindle 3 to which the tool T is fixed, and both sides of the thrust receiving disk 31 are sandwiched from the axial direction via a gap, and a hydrostatic bearing is provided inside the frame 1. Thrust bearings 5 and 5 ′ are provided to receive axial thrust applied to the spindle 3. Further, radial bearings 6 and 6 ′ composed of hydrostatic bearings are provided on both sides of the stator 2 and inside the frame 1 to support the spindle 3. Since the thrust bearings 5, 5 ', the radial bearings 6, 6' and the stator 2 generate heat during rotation, a cooling device 7 for cooling them is provided. The cooling device 7 has a supply port 7 that opens to the outer periphery of the bracket 11 on the non-load side to supply a coolant.
1, a feed pipe 72 extending in the axial direction into the frame 1 and communicating with the supply port 71, and a substantially annular shape so as to surround the thrust bearings 5 and 5 ′ provided at the load-side tip of the frame 1. A cooling groove 73 which is formed and communicates with the inlet pipe 72, and a cooling liquid which is provided in parallel with the inlet pipe 72 to communicate with the cooling groove 73 and discharges the cooling liquid to the outside from an outlet 75 provided in the bracket 11. A tube 74 is provided. Therefore, the cooling device 7 passes the cooling liquid from the supply port 71 through the inlet pipe 72, the cooling groove 73, and the outlet pipe 72, and the stator 2, the thrust bearing 5,
The heat generated from the radial bearings 5 ′ and 6 ′ is absorbed by the cooling liquid and discharged to the outside through the discharge port 75.

[0003]

However, in the prior art, the stator, the thrust bearing, and the radial bearing, which are the heat-generating portions, have only one cooling groove, and two cooling liquid conduits, a feed pipe and a feed pipe. Since they are not in contact with each other, there is a disadvantage that the cooling effect is low, the temperature rise is large, the spindle thermally expands, and the processing accuracy is reduced. SUMMARY OF THE INVENTION It is an object of the present invention to increase a contact area between a cooling liquid pipe of a cooling device and a heat generating portion to enhance a cooling effect of a spindle motor.

[0004]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a stator provided inside a hollow cylindrical frame, a spindle provided inside the stator, and an intermediate portion between the spindles. A thrust bearing provided on the inner side of the frame so as to sandwich the thrust receiving disk from the axial direction via a gap, and the fixed member. A cooling device for a spindle motor including two radial bearings provided on both sides of a child and inside the frame, wherein a feed pipe extending in an axial direction inside the frame and a communication with the feed pipe are provided. An annular first relay groove provided on the outer periphery of the one radial bearing; a plurality of cooling grooves provided around the thrust bearing; and a plurality of cooling grooves communicating with the cooling groove and the first relay groove. cooling An annular second relay groove provided on the outer periphery of the other radial bearing, a plurality of cooling pipes communicating with the second relay groove and the cooling groove, and a communication with the second relay groove And a delivery pipe.

[0005]

When the cooling liquid is fed into the relay groove from the supply port via the inlet pipe by the above means, the outer periphery of the radial bearing is cooled, and then a plurality of cooling pipes passing through the frame from the relay groove are formed. The cooling fluid passes through each cooling groove via the cooling groove, and cools the periphery of the thrust bearing. Further, the outer circumferences of the thrust bearing, the stator, and the radial bearing are cooled from the other end of each cooling groove via a cooling pipe, are sent to the relay groove, are cooled to the radial bearing, and are discharged from the discharge port via the delivery pipe. Is discharged.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
FIG. 1 is a side sectional view showing an embodiment of the present invention, FIG. 2 (a) is a front sectional view along the AA section, and FIG. 2 (b) is a BB section thereof.
FIG. 2C is a front cross-sectional view along the line CC, and FIG. 2D is a front cross-sectional view along the line DD. In the figure, a stator 2 provided inside a hollow cylindrical frame 1, a spindle 3 provided inside the stator 2, and a rotor 4 provided in an intermediate portion of the spindle 3,
Thrust receiving disk 31 provided on the tool T side fixed to the spindle 3, thrust bearings 5 and 5 'provided inside the frame 1, and radial bearings provided on both sides of the stator 2 and inside the frame 1 6 and 6 ′, and sends the coolant to a cooling groove 73 surrounding the thrust bearings 5 and 5 ′ through an inlet pipe 72 extending in the axial direction from the supply port 71 to the inside of the frame 1. The coolant through the outlet 75
The configuration provided with the cooling device 7 for discharging the air from the apparatus is substantially the same as the configuration described in the conventional example. The difference from the conventional one is that the cooling device 7 is configured as follows. That is, the annular first bearings are provided on the surfaces of the radial bearings 6 and 6 ′ in contact with the frame 1.
And the second relay groove 77 are provided, the inlet pipe 72 is communicated with the first relay groove 76, and the outlet pipe 74 is connected to the second relay groove 76.
In the relay groove 77. Thrust bearing 5, 5 '
The cooling groove 73 surrounding the periphery of the cooling groove 73 is divided into four in the circumferential direction, one end of each cooling groove 73 is radially extended, and communicates with the first relay groove 76 via a cooling pipe 78 extending in the axial direction. And radially extend the other end of each cooling groove 73 in the same manner,
It communicates with the second relay groove 77 in the axial direction via the extension building cooling pipe 79. When the coolant is supplied from the supply port 71 to the first relay groove 76 via the supply pipe 72, first, as shown in FIG. 2B, the outer periphery of the radial bearing 6 is cooled. Next, the coolant flows through each cooling groove 73 through four cooling pipes 78 passing through the frame 1 facing the outer periphery of the thrust receiving disk 31 from the first relay groove 76, and as shown in FIG. As shown, the area around the thrust bearings 5, 5 'is cooled. The cooling liquid further flows from the other end of each cooling groove 73 through the cooling pipe 79 through the thrust bearings 5 and 5 ′, the stator 2 and the radial bearing 6.
Of the radial bearing 6 ′, and the radial bearing 6 ′ is cooled and discharged through the discharge pipe 72.
Is discharged from . In the above embodiment, an example in which the cooling groove 4 is divided into four in the circumferential direction has been described, but the number of divisions is not limited to this.

[0007]

As described above, according to the present invention, a plurality of cooling pipes are brought into contact with a thrust bearing, a stator, and a radial bearing to perform cooling.
The cooling area of the cooling device is several times as large as that cooled by the cooling pipe line, and the cooling effect of the spindle motor is significantly enhanced.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention.

FIG. 2A is a front sectional view taken along the line AA of FIG. 1;
1B is a front sectional view taken along the line BB of FIG. 1, FIG. 1C is a front sectional view taken along the line CC of FIG. 1, and FIG.
It is a front sectional view along a section.

FIG. 3 is a side sectional view showing a conventional example.

4A is a front cross-sectional view taken along the A′-A ′ cross section of FIG. 3, and FIG. 4B is a front cross-sectional view taken along the B′-B ′ cross section of FIG.

[Explanation of symbols]

1 frame, 2 stators, 3 spindles, 31 thrust receiving disk, 4 rotors, 5, 5 'thrust bearing,
6, 6 'radial bearing, 7 cooling device, 71 supply port, 7
2 inlet pipe, 73 cooling groove, 74 outlet pipe, 75 outlet, 76 first relay groove, 77 second relay groove, 78, 7
9 Cooling pipe

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-16238 (JP, A) JP-A-2-299440 (JP, A) Fully open 1986-72063 (JP, U) Really open 1987 107553 (JP, U) Japanese Utility Model Hei 5-88851 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) H02K 9/00-9/28

Claims (1)

(57) [Scope of request for utility model registration] A stator provided inside a hollow cylindrical frame; a spindle provided inside the stator; a rotor provided at an intermediate portion of the spindle; and a rotor provided at a tip side of the spindle. A thrust receiving disk, a thrust bearing provided inside the frame so as to sandwich the thrust receiving disk from the axial direction via a gap, and two thrust bearings provided on both sides of the stator and inside the frame. In the cooling device for a spindle motor provided with a radial bearing, an inlet pipe extending in the axial direction inside the frame, an annular second pipe communicating with the inlet pipe, and provided on an outer periphery of the one radial bearing. One relay groove, a plurality of cooling grooves provided around the thrust bearing, a plurality of cooling pipes communicating with the cooling groove and the first relay groove, and an annular ring provided on the outer periphery of the other radial bearing No. A second relay groove, a plurality of cooling pipes communicating with the second relay groove and the cooling groove, and a delivery pipe communicating with the second relay groove. apparatus.