KR20150042456A - The cooling structure of the machine tool - Google Patents

The cooling structure of the machine tool Download PDF

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Publication number
KR20150042456A
KR20150042456A KR20130121106A KR20130121106A KR20150042456A KR 20150042456 A KR20150042456 A KR 20150042456A KR 20130121106 A KR20130121106 A KR 20130121106A KR 20130121106 A KR20130121106 A KR 20130121106A KR 20150042456 A KR20150042456 A KR 20150042456A
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KR
South Korea
Prior art keywords
cooling
motor
housing
passage
spindle
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KR20130121106A
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Korean (ko)
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KR102030565B1 (en
Inventor
정석우
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두산인프라코어 주식회사
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Priority to KR1020130121106A priority Critical patent/KR102030565B1/en
Publication of KR20150042456A publication Critical patent/KR20150042456A/en
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Publication of KR102030565B1 publication Critical patent/KR102030565B1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q11/00—Accessories fitted to machine tools for keeping tools or parts of the machine in good working condition or for cooling work; Safety devices specially combined with or arranged in, or specially adapted for use in connection with, machine tools
    • B23Q11/12—Arrangements for cooling or lubricating parts of the machine
    • B23Q11/126—Arrangements for cooling or lubricating parts of the machine for cooling only
    • B23Q11/127—Arrangements for cooling or lubricating parts of the machine for cooling only for cooling motors or spindles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q11/00—Accessories fitted to machine tools for keeping tools or parts of the machine in good working condition or for cooling work; Safety devices specially combined with or arranged in, or specially adapted for use in connection with, machine tools
    • B23Q11/14—Methods or arrangements for maintaining a constant temperature in parts of machine tools
    • B23Q11/141—Methods or arrangements for maintaining a constant temperature in parts of machine tools using a closed fluid circuit for cooling or heating

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Auxiliary Devices For Machine Tools (AREA)
  • Turning (AREA)

Abstract

The present invention relates to a cooling structure of a machine tool including a front bearing and a rear bearing for supporting a spindle, a spindle motor for rotating the spindle, and a cooling unit for cooling the front bearing, the rear bearing and the spindle motor, The cooling unit is formed on an outer circumferential surface of a first housing that supports the front bearings and is formed on an outer circumferential surface of a motor sleeve provided on an outer circumferential surface of the spindle motor, A motor cooling flow path through which the cooling fluid discharged from the front cooling flow path flows, a rear cooling flow path formed on one surface of the second housing for supporting the rear bearing and through which the cooling fluid discharged from the motor cooling flow path flows, A cooling sleeve formed at a rear end of the motor sleeve, A cooling structure of a machine tool including a recovery cooling flow passage through which a fluid flows.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a cooling structure of a machine tool,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a cooling structure of a machine tool, and more particularly, to a cooling structure of a machine tool using a cooling fluid to solve a problem caused by heat generation in a rotating spindle.

As machine tools have become increasingly faster and more efficient, the use of spindle motors, which can increase spindle speed and lower inertia, has increased.

Conventionally, when a spindle motor is separately mounted, a heat source related to thermal deformation of the spindle is the main bearing. However, as the speed increases, the spindle motor is transformed into a built-in type in which the spindle motor is integrated with the spindle.

FIG. 1 shows an assembled portion of a conventional spindle motor-equipped spindle in which a spindle motor 14 having a rotor 12 and a stator 13 is disposed at a portion of the spindle 10, (10) and the stator (13) is mounted on the spindle housing (16).

In the case of the built-in type in which the spindle motor 14 is integrated with the spindle 10, the heat generated in the bearing housing 20 and the spindle housing 16, which support the spindle bearing 18, A cooling device is added.

1, the cooling oil discharged from the oil pump 23 of the oil cooling apparatus 22 is supplied through the oil passage 7a of the spindle housing 16, and then the outer peripheral surface of the bearing housing 20, The cooling passage formed on the inner circumferential surface of the housing 16 and the cooling passage formed on the outer circumferential surface of the spindle housing 16 are sequentially cooled and then returned to the oil cooler 22.

As described above, in the cooling structure of the conventional built-in spindle motor, the cooling flow path for suppressing the generation of heat of the spindle is applied only to the spindle bearing 18 and the spindle motor 14, There is a problem in that the support bearing 8 can not be cooled.

Therefore, there is no way to prevent heat from moving from the support bearing 8 to the spindle 10, which limits the machining of high-precision workpieces, and causes poor machining of the workpieces.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and provides a cooling structure of a machine tool in which cooling channels are formed not only on the front end side bearings and spindle motors of the spindles but also on the rear end side bearings of the spindles .

The technical object of the present invention is not limited to the above-mentioned technical objects and other technical objects which are not mentioned can be clearly understood by those skilled in the art from the following description will be.

According to an aspect of the present invention, there is provided a machine tool including a front bearing and a rear bearing for supporting a spindle, a spindle motor for rotating the spindle, and a cooling unit for cooling the front bearing, the rear bearing, Wherein the cooling unit is formed on an outer circumferential surface of a first housing for supporting the front bearing and has a front cooling flow passage through which a cooling fluid supplied from the outside flows; A motor cooling flow path formed on an outer circumferential surface of a motor sleeve provided on an outer circumferential surface of the spindle motor and through which a cooling fluid discharged from the front cooling flow path flows; A rear cooling flow passage formed on one side of the second housing for supporting the rear bearing and through which the cooling fluid discharged from the motor cooling flow passage flows; And a recovery cooling flow path formed at a rear end of the motor sleeve and through which a cooling fluid discharged from the rear cooling flow path flows; .

The motor cooling passage is formed along a spiral first rib formed at a predetermined length from one end of the outer circumferential surface of the motor sleeve toward the other end, And a pair of second ribs spaced apart from each other.

The rear cooling flow path may include a flow groove formed along the periphery of the hollow formed at the center of the second housing, a supply path connecting the other surface of the second housing to the flow groove, And a boss provided on the flow groove so as to be disposed between the supply passage and the end of the discharge passage, wherein the boss is disposed on the flow groove so as to communicate with the other surface of the second housing, .

The cooling structure of the machine tool may include: a rear flange provided on one surface of the second housing to seal the flow groove; Wherein a closed flow path is formed between a pair of the sealing members on one surface of the rear flange, and the closed flow path is disposed to face the flow groove.

According to the present invention, since the cooling flow path applied to the machine tool is formed to pass through the front end side bearing of the spindle, the spindle motor, and the rear end side bearing of the spindle, heat generation at all portions of the spindle is suppressed, , There is an advantage that a high-precision workpiece can be machined.

1 is a side cross-sectional view showing a conventional machine tool having a built-in type spindle motor.
2 is a perspective view showing a front end of a machine tool according to an embodiment of the present invention.
3 is a side sectional view showing a main part of the front end of the machine tool according to the embodiment of the present invention.
4 is a perspective view illustrating a first housing of a machine tool according to an embodiment of the present invention.
5 is a side sectional view showing a motor cooling channel of a machine tool according to an embodiment of the present invention.
6 is a perspective view illustrating a motor sleeve of a machine tool according to an embodiment of the present invention.
7 is a side sectional view showing a motor sleeve of a machine tool according to an embodiment of the present invention.
8 is a side sectional view showing a main portion of a rear end of a machine tool according to an embodiment of the present invention.
9 is a front perspective view showing a second housing of a machine tool according to an embodiment of the present invention.
10 is a side perspective view of a second housing of a machine tool according to an embodiment of the present invention.
11 is a rear perspective view illustrating a second housing of a machine tool according to an embodiment of the present invention.
12 is a front perspective view of a rear flange of a machine tool according to an embodiment of the present invention.
13 and 14 are side cross-sectional views illustrating a recovery cooling channel of a machine tool according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The sizes and shapes of the components shown in the drawings may be exaggerated for clarity and convenience. In addition, terms defined in consideration of the configuration and operation of the present invention may be changed according to the intention or custom of the user, the operator. Definitions of these terms should be based on the content of this specification. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Of course.

FIG. 2 is a perspective view showing the front end of a machine tool according to an embodiment of the present invention, FIG. 3 is a side sectional view showing a main part of a front end of a machine tool according to an embodiment of the present invention, 1 is a perspective view of a first housing of a machine tool according to an embodiment. 2 to 4, the structure of the front cooling channel of the cooling unit of the cooling structure of the machine tool of the present invention will be described in detail.

2, a first housing 110 having a hollow ring shape is provided at a front end side of a body 60 forming an outer shape of the machine tool, and a cooling fluid supplied from the outside is supplied to the first housing 110, Cooling passage 100 formed on the outer circumferential surface of the front cooling passage.

In the lower portion of the front side of the body 60, a supply flow path 61 for supplying a cooling fluid to the front cooling flow path 100 is provided. In the upper portion of the front side of the body 60, (See FIG. 5) to supply a cooling fluid that has flowed through the supply passage 61 to the motor cooling flow passage 200 (see FIG. 5) (100) and then supplied to the motor cooling passage (200) through the first connection passage (63), thereby removing a heat source generated in the front bearing (30).

3 and 4, the first housing 110 supports the front bearing 30 supporting the front end of the spindle 10, and includes a pair of front bearings 30 on the inner circumferential surface thereof, .

According to an embodiment of the present invention, the first housing 110 has a plurality of outer circumferential surfaces. The outer circumferential portion of the first housing 110 and the front end of the body 60 supporting the first housing 110 And the front cooling passage 100 is formed between the stepped portions 62.

A sealing groove 116 is formed adjacent to one side of the front cooling passage 100 of the first housing 110. A sealing member 114 such as an O-ring is inserted into the sealing groove 116, Thereby sealing the flow path 100 and preventing leakage of the cooling fluid.

FIG. 5 is a side cross-sectional view illustrating a motor cooling channel of a machine tool according to an embodiment of the present invention, and FIGS. 6 and 7 are a perspective view and a side view showing a motor sleeve of a machine tool according to an embodiment of the present invention. 5 to 7, the structure of the motor cooling passage in the cooling section of the cooling structure of the machine tool of the present invention will be described in detail.

5, the spindle motor 20 includes a rotor 22 and a stator 24 for rotating the spindle 10. The rotor 22 is disposed on the outer periphery of the spindle 10, And the stator 24 is mounted on the inner circumferential surface of the motor sleeve 50.

A motor cooling passage 200 is formed between the outer circumferential surface of the motor sleeve 50 and the inner circumferential surface of the closed end of the body 60.

That is, the cooling fluid that has flowed through the front cooling passage 100 is supplied from the first connection passage 63 to one end of the outer circumferential surface of the motor sleeve 50, and the supplied cooling fluid passes through the motor sleeve 50 And flows in the direction of the spiral toward the other end to remove the heat source generated in the spindle motor 20. [

6 and 7, the motor sleeve 50 is formed in a cylindrical shape having an open inside so as to have a predetermined length, and has a first rib 210 formed in a spiral direction from one end to the other end, The motor cooling passage 200 is formed between the spiral first ribs 210 and the inner circumferential surface of the body 60 at the stop.

The cooling fluid that has flowed through the motor cooling channel 200 is supplied to the rear cooling channel 300 to be described later through the second connection channel 65 formed at the rear end of the motor sleeve 50.

FIG. 8 is a side sectional view showing a main portion of a rear end of a machine tool according to an embodiment of the present invention, FIGS. 9 to 11 are a front perspective view showing a second housing of a machine tool according to an embodiment of the present invention, FIG. 12 is a front perspective view of a rear flange of a machine tool according to an embodiment of the present invention. FIG. 9 to 12, the structure of the rear cooling channel of the cooling unit of the cooling structure of the machine tool of the present invention will be described in detail.

8, a second housing 310 is provided on a rear end side of the spindle 10, and a rear bearing 40 for supporting a rear end of the spindle 10 on an inner circumferential surface of the second housing 310, Lt; / RTI >

The rear cooling passage 300 is formed on one surface of the second housing 310 and communicates with the second connection passage 65 to flow in the motor cooling passage 200, After the heat source generated in the rear bearing (40) is removed, the cooling fluid is discharged to the recovery cooling passage (400), which will be described later, through the third connection passage (67).

9 to 11, the rear cooling passage 300 includes a flow groove 320, a supply passage 330, a discharge passage 340, a boss 350, and the like.

The flow grooves 320 are formed on one surface of the second housing 310 along the circumference of the hollow formed at the center of the second housing 310, The heat source generated in the rear bearing 40 is removed.

The supply path 330 is provided inside the second housing 310 to communicate the other surface of the second housing 310 with the flow groove 320 and is connected to the supply port 330 of the supply path 330 332 are connected to the second connection passage (65) at the other side of the second housing (310).

Therefore, the cooling fluid flowing through the motor cooling channel 200 flows into the supply channel 330 through the supply port 332, and then flows through the flow channel 320.

The discharge passage 340 communicates the other surface of the second housing 310 with the flow grooves 320 in the same manner as the supply passage 330. The discharge passage 340 is spaced apart from the supply passage 330 by a predetermined distance, (Not shown). The outlet 342 of the discharge passage 340 is connected to the third connection passage 67 at the other surface of the second housing 310.

The cooling fluid having the heat source of the rear bearing 40 removed while flowing through the flow grooves 320 is discharged to the discharge port 342 through the discharge passage 340 and then flows into the third connection passage 67, To the recovery cooling passage (400).

11, the boss 350 is provided on the flow groove 320 so as to be disposed between the supply passage 330 and the end of the discharge passage 340, The flow path is divided so that the cooling fluid supplied to the flow grooves 320 and the cooling fluid discharged through the discharge path 330 after flowing through the flow grooves 320 are not mixed with each other.

12, the machine tool according to an embodiment of the present invention further includes a rear flange 500, which is disposed in the second housing (not shown) to seal the flow groove 320 310).

That is, a pair of grooves 522 are formed on one surface of the rear flange 500, and the pair of grooves 522 is provided with a sealing member 520 such as an O- A sealing flow path 510 formed between the flow grooves 320 is disposed facing the flow grooves 320 to seal the flow grooves 320 as shown in FIGS.

The cooling fluid that has flowed through the rear cooling channel 300 is supplied to the recovery channel 300 to be described later through the third connection channel 67 formed at the rear end of the motor sleeve 50.

13 and 14 are side cross-sectional views illustrating a recovery cooling channel of a machine tool according to an embodiment of the present invention. 13 and 14, the structure of the recovery cooling passage in the cooling section of the cooling structure of the machine tool of the present invention will be described in detail.

Referring to FIG. 13, which is a side sectional view showing the upper portion of the rear end side of the spindle 10, the cooling fluid discharged through the discharge passage 330 of the rear cooling passage 300 flows through the third connection passage 67 And is supplied to the recovered cooling channel 400 which is formed at the rear end of the motor sleeve 50.

Specifically, the recovery cooling passage 400 is formed between a pair of second ribs 410 spaced apart from the other end of the outer circumferential surface of the motor sleeve 50 by a predetermined distance, and an inner peripheral surface of the rear end side of the body 60 6 and 7), the cooling fluid flowing through the recovery and cooling passage 400 removes the heat source generated by the spindle motor 20 once again.

14, which is a side sectional view showing a lower portion of the rear end side of the spindle 10, a cooling fluid having flowed through the recovery cooling flow passage 400 is discharged through a discharge flow passage 69 To the outside of the body (60).

The reason why the motor cooling passage 200 and the recovered cooling passage 400 are formed separately from the outer circumferential surface of the motor sleeve 50 is that after flowing the motor cooling passage 200, 300 and the cooling fluid discharged to the outside after flowing through the rear cooling channel 300 is prevented from being mixed with the cooling fluid flowing through the rear cooling channel 300 and the efficiency of removing the heat source generated from the spindle motor 20 is increased .

In general, the movement of the cooling fluid flowing along the cooling structure of the machine tool according to an embodiment of the present invention is such that the cooling fluid supplied from the outside flows through the supply channel 61 to the front cooling channel 100 So that the heat source generated in the front bearing 30 is removed.

The cooling fluid flowing through the front cooling passage 100 is supplied to the motor cooling passage 200 through the first connection passage 63 and the cooling fluid flowing through the motor cooling passage 200 is supplied to the spindle motor 200. [ The heat source generated in the heat exchanger 20 is removed.

The cooling fluid flowing through the motor cooling channel 200 is supplied to the rear cooling channel 300 through the second connection channel 65. The cooling fluid flowing through the rear cooling channel 300 flows through the rear bearing 300, The heat source generated in the heat exchanger 40 is removed.

The cooling fluid that has flowed through the rear cooling channel 300 is supplied to the recovery cooling channel 400 through the third connection channel 67. The cooling fluid flowing through the recovery channel 400 is supplied to the spindle motor 400, The heat source generated in the heat exchanger 20 is once again removed, and then is discharged to the outside through the discharge passage 69.

Here, the cooling fluid discharged to the outside is cooled and then supplied to the front cooling channel 100 through the supply channel 61 so that the cooling fluid circulates through the cooling channels according to an embodiment of the present invention.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims. Accordingly, the true scope of the present invention should be determined by the following claims.

10: spindle 20: spindle motor
30: front bearing 40: rear bearing
50: motor sleeve 100: forward cooling flow path
110: first housing 200: motor cooling flow path
210: first rib 300: rear cooling flow passage
310: second housing 320: flow groove
330: supply path 340: discharge path
350: boss 400: recovered cooling flow passage
410: second rib 500: rear flange
510: Closed channel 520: Closure member

Claims (4)

A cooling structure of a machine tool including a front bearing and a rear bearing for supporting a spindle, a spindle motor for rotating the spindle, and a cooling unit for cooling the front bearing, the rear bearing, and the spindle motor,
The cooling unit includes:
A front cooling passage formed on an outer circumferential surface of the first housing for supporting the front bearing and through which a cooling fluid supplied from the outside flows;
A motor cooling flow path formed on an outer circumferential surface of a motor sleeve provided on an outer circumferential surface of the spindle motor and through which a cooling fluid discharged from the front cooling flow path flows;
A rear cooling flow passage formed on one side of the second housing for supporting the rear bearing and through which the cooling fluid discharged from the motor cooling flow passage flows; And
A recovery cooling flow path formed at a rear end of the motor sleeve and through which a cooling fluid discharged from the rear cooling flow path flows; The cooling structure of the machine tool. The method according to claim 1,
Wherein the motor cooling flow path is formed along a spiral first rib formed at a predetermined length from one end of the outer peripheral surface of the motor sleeve toward the other end,
Wherein the recovery cooling flow path is formed by a pair of second ribs spaced apart from each other at the other end of the outer circumferential surface of the motor sleeve. The method according to claim 1,
The rear cooling flow passage
A flow groove formed along the periphery of the hollow formed at the center of the second housing,
A supply passage connecting the other surface of the second housing and the flow groove,
A discharge passage spaced apart from the supply passage by a predetermined distance and communicating the other surface of the second housing with the flow groove,
And a boss provided on the flow groove so as to be disposed between the supply passage and the end of the discharge passage. The method of claim 3,
A rear flange provided on one surface of the second housing to seal the flow groove; Further comprising:
Wherein a closed flow path is formed between a pair of the sealing members on one surface of the rear flange, and the closed flow path is disposed facing the flow groove.
KR1020130121106A 2013-10-11 2013-10-11 The cooling structure of the machine tool KR102030565B1 (en)

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KR102030565B1 KR102030565B1 (en) 2019-10-11

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117748806A (en) * 2023-12-20 2024-03-22 浙江金龙电机股份有限公司 Machine tool spindle motor and control method thereof

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0574703U (en) * 1992-03-24 1993-10-12 豊田工機株式会社 Spindle device

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0574703U (en) * 1992-03-24 1993-10-12 豊田工機株式会社 Spindle device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117748806A (en) * 2023-12-20 2024-03-22 浙江金龙电机股份有限公司 Machine tool spindle motor and control method thereof
CN117748806B (en) * 2023-12-20 2024-06-04 浙江金龙电机股份有限公司 Machine tool spindle motor and control method thereof

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