TWI627016B - Bearing preloading device for machining spindle - Google Patents

Abstract

A bearing pre-pressing device for processing a spindle, which is arranged in the spindle sleeve to erect a rotating shaft with a plurality of bearings, a hydraulic mechanism is provided with a ring seat in the spindle sleeve, and a piston ring is arranged in the ring seat. A hydraulic chamber having a buffer portion and a pushing portion is disposed between the ring seat and the piston ring, and a first pressure regulating component and a second pressure regulating component are connected to the hydraulic chamber to maintain and adjust the hydraulic chamber. Hydraulically, and forming a hydraulic film surrounding the outer ring surface of the piston ring in the buffer portion of the hydraulic chamber, the hydraulic pressure in the moving portion of the hydraulic chamber is pushed by the piston ring to drive the outer ring of the bearing, so that the bearing generates radial direction to the rotating shaft Pre-pressure; thereby, the first and second pressure regulating components are used to maintain proper hydraulic pressure in the hydraulic chamber, and the rotating shaft is forced by the radial pressure of the hydraulic film and the bearing in the buffer portion of the hydraulic chamber to change the overall structure of the processing spindle The rigidity and damping effect, and effectively suppress the phenomenon of cutting flutter, thereby achieving the practical benefit of greatly improving the machining accuracy.

Description

Bearing preloading device for machining spindle

In particular, the present invention provides a hydraulic pressure in a hydraulic chamber, and a radial preload of a hydraulic film and a bearing in a buffer portion of the hydraulic chamber to support the rotating shaft, thereby effectively suppressing the chattering phenomenon and greatly improving Bearing preloading device for machining spindle with machining precision.

According to the processing spindle of the processing machine, the machining feed amount is often changed during the cutting process. When the heavy cutting machining with a large feed amount is performed, the rotation axis of the machining spindle will bear a large cutting reaction force, and The bearing pre-pressure amount of the machining spindle can be increased, so that the rotation shaft has better rigidity to meet the demand of heavy cutting processing, and when the light cutting processing with small feed amount is performed, the rotation shaft of the machining spindle is rotated at a high rotation speed. , the bearing pre-pressure of the machining spindle must be reduced to prevent the bearing from overheating and being damaged; however, whether the natural frequency of the overall structure of the machining spindle is close to or the same as the cutting frequency, whether in heavy cutting or light cutting, Resonance occurs, and the phenomenon of cutting flutter occurs, which in turn affects the machining accuracy and quality. In order to avoid the phenomenon of cutting flutter, in addition to changing the machining parameters such as the spindle speed and the cutting feed rate, the bearing of the machining spindle can be adjusted. The amount of pre-pressure is used to change the rigidity of the overall structure of the machining spindle, so that the natural frequency of the overall structure of the machining spindle avoids cutting Rate, and avoid the phenomenon of cutting flutter during the cutting process; please refer to the new patent case of Taiwan Bulletin No. M315127 "Spindle Mandrel Changeable Preloading Device" as shown in Figures 1 and 2, It is mounted in the processing machine main shaft 10 with a mandrel 12 erected by two bearings 11a, 11b, wherein the outer rings 111a, 111b of the two bearings 11a, 11b When the force is respectively pushed to the two ends of the mandrel 12, the inner rings 112a, 112b of the two bearings 11a, 11b can be pre-stressed, and the mandrel 12 is tightly supported, and between the two bearings 11a, 11b. a spacer 13 is provided, and the two ends of the spacer 13 are respectively connected to the outer rings 111a and 111b of the two bearings 11a and 11b, and a guide groove 131 is disposed on the outer ring surface of the spacer ring 13; The temperature device 14 is connected to the flow guiding groove 131 of the spacer ring 13 to output a warming liquid flowing through the flow guiding groove 131 of the spacer ring 13 when the warming liquid flows through the guiding groove 131 of the spacer ring 13 The spacer 13 generates thermal expansion to push the outer rings 111a, 111b of the two bearings 11a, 11b, so that the inner rings 112a, 112b of the two bearings 11a, 11b generate a radial pre-stress to firmly support the mandrel 12. In turn, the rigidity of the processing machine spindle 10 can be increased to meet the cutting reaction force during processing; however, the processing machine spindle 10 still has the following disadvantages in use:

1. The heating liquid outputted by the heating device 14 is used to cause the spacer 13 to thermally expand, so that the two bearings 11a, 11b generate radial pre-pressure to meet the processing requirements; however, when the warming liquid circulates in the partition After the guide groove 131 of the ring 13, the thermal expansion of the spacer 13 is relatively slow, and the required amount of thermal expansion cannot be immediately achieved. In contrast, the two bearings 11a, 11b cannot quickly generate an appropriate pre-pressure. In response to the demand of the machining operation, the phenomenon of cutting flutter cannot be quickly and effectively suppressed during the machining process, thereby affecting the machining accuracy.

2. When the warming liquid flows through the flow guiding groove 131 of the spacer ring 13, in addition to causing thermal expansion of the spacer ring 13, the outer ring seat of the processing machine main shaft 10 and the like are also thermally expanded by the influence of the warming liquid. The distance between the two bearings 11a, 11b will increase with the thermal expansion of the ring seat outside the processing machine main shaft 10, and the two bearings 11a, 11b will not be able to stably generate an appropriate pre-pressure, thereby affecting the machining accuracy.

In view of this, the inventor has been engaged in research and development and production experience of related industries for many years, and has conducted in-depth research on the problems currently faced. After long-term efforts and research, he finally developed a bearing preloading device for machining spindles. Effectively improving the shortcomings of the prior art, this is the design tenet of the present invention.

A first object of the present invention is to provide a bearing preloading device for machining a spindle, which is provided with a rotating shaft in a plurality of bearings in a spindle sleeve seat, and a hydraulic mechanism is provided with a ring seat in the spindle sleeve, in the ring a piston ring is arranged in the seat, and a hydraulic chamber having a buffer portion and a pushing portion is disposed between the ring seat and the piston ring, and a first pressure regulating component and a second pressure regulating component are connected to the hydraulic chamber. Maintaining and adjusting the hydraulic pressure in the hydraulic chamber, and forming a hydraulic film surrounding the outer ring surface of the piston ring in the buffer portion of the hydraulic chamber, and the hydraulic pressure in the moving portion of the hydraulic chamber shifts the piston ring to drive the outer ring of the bearing, so that The bearing generates a radial pre-pressure on the rotating shaft; thereby, the first and second pressure regulating components are used to maintain an appropriate hydraulic pressure in the hydraulic chamber, and the hydraulic pre-pressure in the buffer portion of the hydraulic chamber and the radial preload of the bearing are tightly supported. The rotation axis can change the rigidity and damping effect of the overall structure of the machining spindle, so as to effectively suppress the phenomenon of cutting flutter, thereby achieving the practical purpose of greatly improving the machining accuracy.

A second aspect of the present invention provides a bearing preloading device for processing a spindle, wherein the hydraulic mechanism is provided with a hydraulic chamber having a buffer portion and a pushing portion between the ring seat and the piston ring, and is connected to the hydraulic chamber. a first pressure regulating component and a second pressure regulating component to maintain and adjust the hydraulic pressure in the hydraulic chamber, so that a hydraulic film surrounding the outer ring surface of the piston ring is formed in the buffer portion of the hydraulic chamber, and the hydraulic pressure in the moving portion of the hydraulic chamber is The piston ring is pushed, and the piston ring drives the bearing to generate a radial pre-pressure on the rotating shaft, and the hydraulic film and the bearing pre-pressure are pressed to support the rotating shaft. When the rotating bearing is subjected to a large cutting reaction force instantaneously, The buffer portion of the hydraulic chamber buffers the oil pressure fed back from the shift chamber to improve the rigidity and damping effect of the overall structure of the machining spindle and prevent the shaft from being generated. Offset, which achieves the practical purpose of greatly improving machining accuracy.

Conventional part:

10‧‧‧Processing machine spindle

11a‧‧‧ Bearing

111a‧‧‧Outer ring

112a‧‧‧ inner circle

11b‧‧‧ Bearing

111b‧‧‧Outer ring

112b‧‧‧ inner circle

12‧‧‧ mandrel

13‧‧‧ spacer

131‧‧‧Guide trough

14‧‧‧Heating device

Part of the invention:

20‧‧‧ spindle holder

201‧‧‧ 挡缘

202‧‧‧First runner

203‧‧‧Second runner

21‧‧‧ shaft

22a‧‧‧First bearing

221a‧‧‧First outer ring

222a‧‧‧First inner circle

223a‧‧‧First Ball

22b‧‧‧second bearing

221b‧‧‧ second outer ring

222b‧‧‧Second inner circle

223b‧‧‧second ball

23a‧‧‧First outer ring

23b‧‧‧Second outer ring

24a‧‧‧First inner septum

24b‧‧‧Second inner ring

25‧‧‧Rotary drive source

26‧‧‧ broach mechanism

30‧‧‧Hydraulic institutions

31‧‧‧ ring seat

32‧‧‧Piston ring

321‧‧‧

33‧‧‧ hydraulic room

331‧‧‧ buffer

332‧‧‧Move

34‧‧‧First pressure regulating component

341‧‧‧ first ontology

3411‧‧‧First room

342‧‧‧First Piston

343‧‧‧First stop

35‧‧‧Second voltage regulator

351‧‧‧Second ontology

3511‧‧‧Second room

352‧‧‧second piston

353‧‧‧second stop

354‧‧‧Flexible components

Figure 1 is a schematic diagram of the structure of the Taiwan Patent No. M315127.

Figure 2: Schematic diagram of the action of Taiwan Patent No. M315127.

Figure 3: Schematic diagram of the structure of the present invention.

Figure 4: is an enlarged schematic view of part A of Figure 3.

Figure 5: is an enlarged schematic view of part B of Figure 3.

Fig. 6 is an enlarged schematic view of a portion C of Fig. 3.

Figure 7: is an enlarged schematic view of part D of Figure 3.

Figure 8 is an enlarged schematic view of part E of Figure 3.

In order to make the present invention more fully understood by the reviewing committee, the preferred embodiment and the drawings are described in detail as follows: Referring to Figures 3-8, the machining spindle of the present invention is attached to the spindle housing 20 The inner casing is provided with a plurality of bearings for erecting a rotating shaft 21; in the embodiment, the main shaft sleeve 20 is provided with a first bearing 22a which is disposed at an upper and lower interval for erecting the upper end of the rotating shaft 21, And a second bearing 22b provided with two upper and lower spacings for arranging the lower end of the rotating shaft 21, wherein the two first bearings 22a are angular contact bearings, and the two first bearings 22a are respectively provided with contacts. a first outer ring 221a, a first inner ring 222a and a first ball 223a, and a first outer ring 23a that is connected to the inner ends of the first outer ring 221a and abutting between the two first bearings 22a a first inner spacer 24a at an inner end of the first inner ring 222a, so that the first outer ring 221a of the two first bearings 22a can be axially moved upward, and the first bearing 22a is changed. a contact angle of an outer ring 221a, a first inner ring 222a and a first ball 223a, so that the two first bearings 22a At the same time, a radial pre-pressure is generated on the rotating shaft 21, and the rotating shaft 21 is moved upward. The second bearing 22b is also an angular contact bearing, and the second bearing 22b is respectively provided with a contact angle. a second outer ring 221b, a second inner ring 222b and a second ball 223b, and a second outer ring 23b connected to the inner end of the second outer ring 221b and the second outer ring 22b are disposed between the two second bearings 22b a second inner spacer 24b at the inner end of the inner ring 222b, and a retaining edge 201 disposed on the spindle sleeve 20 to block the axial displacement of the second outer ring 221b of the second bearing 22b. When the two first bearings 22a drive the rotating shaft 21 to move upward, the second inner ring 222b of the two second bearings 22b moves upward with the rotating shaft 21, and changes the second of the second bearing 22b. The contact angles of the outer ring 221b, the second inner ring 222b and the second ball 223b cause the two second bearings 22b to simultaneously generate a radial pre-pressure on the rotating shaft 21, and the spindle housing 20 is provided with The rotary drive source 25 of the built-in motor is configured to drive the rotary shaft 21 to rotate, and the rotary shaft 21 is provided with a broach mechanism 26 for performing a broach or a loose knife action. Since the rotary drive source 25 and the broach mechanism 26 are conventional technologies and are not the focus of the present invention, they are not described in detail; a hydraulic mechanism 30 is mounted in the spindle housing 20, and the hydraulic mechanism 30 is A ring seat 31 is disposed, and a piston ring 32 is disposed in the ring seat 31, and the piston ring 32 is disposed outside the two first bearings 22a, and is disposed between the ring seat 31 and the piston ring 32. A hydraulic pressure chamber 33 is provided. The hydraulic chamber 33 is provided with a buffer portion 331 which is an annular gap between the inner ring surface of the ring seat 31 and the outer ring surface of the piston ring 32. The upper end of the buffer portion 331 is provided. The movable portion 332 is connected to the buffer portion 331 of the hydraulic chamber 33, and a hydraulic film that surrounds the outer ring surface of the piston ring 32 is formed in the buffer portion 331 and is then passed through the buffer portion 331. The hydraulic pressure is input into the portion 332, and the piston ring 32 is pushed upward by the hydraulic pressure in the pushing portion 332. The piston ring 32 drives the first outer ring 221a of the two first bearings 22a to simultaneously axially displace the shaft. Upper end position of 21 The radial preload is generated; in the embodiment, the piston ring 32 is provided with an abutting edge 321 for upwardly pushing the first outer ring 221a of the two first bearings 22a; in addition, due to the two first bearings The first inner ring 222a of the second bearing 22a and the second inner ring 222b of the second bearing 22b are respectively sleeved and fixed on the outer ring surface of the rotating shaft 21, and the two first bearings 22a are pushed up by the piston ring 32. When the first outer ring 221a is moved, the two first bearings 22a can axially displace the rotating shaft 21 and the second second bearing 22b by the displacement of the first ball 223a and the first inner ring 222a. The inner ring 222b moves upward with the rotating shaft 21, and the retaining edge 201 of the main shaft sleeve 20 stops the axial displacement of the second outer ring 221b of the second bearing 22b. The contact angle of the second outer ring 221b, the second inner ring 222b, and the second ball 223b of the second bearing 22b causes the two second bearings 22b to simultaneously generate a radial pre-pressure to the lower end position of the rotating shaft 21, and The pre-pressure of the first bearing 22a, the hydraulic film in the buffer portion 331 of the hydraulic chamber 33, and the pre-pressure of the two second bearings 22b Supporting the rotating shaft 21; in the embodiment, the main shaft housing 20 is provided with a first flow passage 202 and a second flow passage 203, and the first flow passage 202 is connected to the buffer portion 331 of the hydraulic chamber 33, the second The flow passage 203 communicates with the pushing portion 332 of the hydraulic chamber 33, and the first flow passage 202 of the spindle housing 20 can input hydraulic pressure to the buffer portion 331 and the pushing portion 332 of the hydraulic chamber 33, and can be circulated to the spindle housing 20 The second flow channel 203 is connected to the first flow channel 202 of the spindle housing 20; and the second pressure regulating component 34 is connected to the second flow channel 203 of the spindle housing 20; The first pressure regulating component 34 and the second pressure regulating component 35 are respectively connected to the hydraulic chamber 33 via the first flow channel 202 and the second flow channel 203 of the spindle housing 20 to maintain and adjust the hydraulic chamber 33. The first pressure regulating component 34 is provided with a first body 341. The first body 341 is provided with a first chamber 3411. The first body 341 is connected to the first chamber 3411. The first flow channel 202 of the spindle sleeve 20 is disposed, and the first piston 342 is disposed inside, and the first end block 343 is locked at the other end to push the first piston 342 against the first piston 342. The block 343 drives the first piston 342 to be displaced in the first chamber 3411 of the first body 341 to manually adjust the hydraulic pressure in the hydraulic chamber 33, and the second pressure regulating component 35 is provided with the second body 351. A second chamber 3511 is disposed in the second body 351. One end of the second chamber 3511 of the second body 351 communicates with the second flow path 203 of the spindle housing 20, and a second piston 352 is disposed therein. The second end of the second piston 352 and the second stop 353 is further provided with a spring elastic member 354 to push the second piston 352 against the hydraulic pressure. When the hydraulic pressure in the chamber 33 changes, the second piston 352 is pushed against the elastic force of the elastic member 354, and the second piston 352 is elastically displaced in the second chamber 3511 of the second body 351 to automatically adjust the The hydraulic pressure in the hydraulic chamber 33.

Referring to FIGS. 3-8, the machining spindle of the present invention is equipped with a cutter (not shown) at the lower end of the rotary shaft 21 during the machining operation, and the first pressure regulating component 34 can be utilized. The first stopper 343 drives the first piston 342 to be displaced in the first chamber 3411 of the first body 341 to manually adjust the hydraulic pressure in the hydraulic chamber 33, for example, when the hydraulic pressure in the hydraulic chamber 33 is insufficient. The first stopper 343 is locked to move the first piston 342 to increase the hydraulic pressure in the hydraulic chamber 33, and the hydraulic pressure of the hydraulic mechanism 30 is caused by the first pressure regulating component 34 and the second pressure regulating component 35. An appropriate hydraulic pressure is maintained in the chamber 33, and a hydraulic film that surrounds the outer ring surface of the piston ring 32 is formed in the buffer portion 331 of the hydraulic chamber 33, and the hydraulic pressure in the pushing portion 332 of the hydraulic chamber 33 shifts the piston ring 32. And the piston ring 32 is pushed upward to axially displace the first outer ring 221a of the two first bearings 22a, and the first outer ring 221a, the first ball 223a and the first of the two first bearings 22a are changed. The contact angle of the inner ring 222a causes the two first bearings 22a A radial pre-pressure is generated at the upper end position of the rotating shaft 21, and the first outer ring 221a of the two first bearings 22a is axially displaced when the piston ring 32 is pushed upward, except that the first of the two first bearings 22a is changed. In addition to the contact angle of the outer ring 221a, the first ball 223a and the first inner ring 222a, the two first bearings 22a can drive the rotating shaft 21 to move upward, so that the second inner ring 222b of the two second bearings 22b Moving the shaft 21 upward, and changing the contact angles of the second outer ring 221b, the second inner ring 222b and the second ball 223b of the two second bearings 22b, so that the two second bearings 22b simultaneously serve the rotating shaft 21 The lower end position generates a radial pre-pressure; thereby, in the process, the pre-pressure generated by the two first bearing 22a and the second second bearing 22b is used to firmly support the rotating shaft 21, and the hydraulic assembly 30 is utilized. The hydraulic film in the buffer chamber 301 surrounds and supports the piston ring 32 and the rotating shaft 21, thereby increasing the rigidity and damping effect of the overall structure of the processing spindle, so as to meet the needs of the machining operation, and when the rotating shaft 21 bears a moment, a large cutting reaction force is generated. When the cutting reaction force is about to The pressure chamber 302 of the hydraulic unit 30 generates a feedback pressure. Since the buffer portion 331 of the hydraulic chamber 33 is an annular gap, the oil pressure in the pushing portion 332 is not easily returned to the buffer portion 331, and the hydraulic chamber can be utilized. The buffer portion 331 of 33 buffers the oil pressure fed back by the pushing portion 332 to improve the rigidity and damping effect of the overall structure of the machining spindle, and prevents the rotation of the rotating shaft 21 to greatly improve the machining accuracy; in addition, when the rotating shaft 21 is After the driving is rotated, the hydraulic pressure in the buffer portion 331 and the pushing portion 332 of the hydraulic chamber 33 is gradually increased by the temperature, and the hydraulic pressure in the buffer portion 331 and the pushing portion 332 of the hydraulic chamber 33 is gradually increased. The hydraulic pressure in the first flow channel 202 and the second flow channel 203 of the first pressure regulating component 34 are respectively input into the first body 341 of the first pressure regulating component 34 and the second body 351 of the second pressure regulating component 35, wherein When the increased hydraulic pressure is input into the second body 351 of the second pressure regulating component 35, even if the second piston 352 is elastically displaced in the second chamber 3511 of the second body 351, The hydraulic pressure in the hydraulic chamber 33 is automatically adjusted to maintain an appropriate hydraulic pressure in the hydraulic chamber 33, and further, the hydraulic pressure film in the buffer portion 331 of the hydraulic chamber 33 and the radial preload of the two first bearings 22a and the second bearings 22b. By tightly supporting the rotating shaft, the rigidity and damping effect of the overall structure of the machining spindle can be changed, so as to effectively suppress the chattering phenomenon, thereby achieving the practical benefit of greatly improving the machining accuracy.

Accordingly, the present invention is a practical and progressive design, but it has not been disclosed that the same products and publications are disclosed, thereby permitting the invention patent application requirements, and applying in accordance with the law.

Claims (9)

A bearing preloading device for machining a spindle, comprising: a spindle sleeve; a rotating shaft: being threaded in the spindle sleeve; a plurality of array bearings: being disposed in the spindle sleeve for erecting the rotating shaft, Each bearing is provided with an outer ring, an inner ring and a ball; a hydraulic mechanism is provided with a ring seat in the spindle sleeve, and a piston ring is arranged in the ring seat, and a ring is arranged between the ring seat and the piston ring a hydraulic chamber having a buffer portion and a pushing portion, wherein the hydraulic chamber is provided with a buffer portion having an annular gap between the inner annular surface of the ring seat and the outer ring surface of the piston ring, and the upper end of the buffer portion is provided a first pressure regulating component and a second pressure regulating component are connected to the hydraulic chamber, and the hydraulic pressure in the hydraulic chamber is maintained and adjusted, and the piston ring of the hydraulic chamber is surrounded by the piston ring. a hydraulic film of the outer ring surface, wherein the hydraulic pressure in the pushing portion of the hydraulic chamber shifts the piston ring, and the piston ring drives the outer ring of the at least one bearing for axial displacement, so that the at least one bearing generates radial direction to the rotating shaft Pre-pressure. The bearing preloading device for processing a spindle according to claim 1, wherein the spindle sleeve is provided with at least one first bearing for locating the upper end of the rotating shaft and at least one for locating the lower end of the rotating shaft. Second bearing. The bearing preloading device of the machining spindle according to the second aspect of the patent application, wherein the piston ring of the hydraulic mechanism is disposed outside the first bearing at the upper end of the rotating shaft. The bearing preloading device of the machining spindle according to the second aspect of the patent application, wherein the spindle sleeve is provided with a retaining edge for blocking the axial displacement of the second outer ring of the second bearing. The bearing preloading device of the processing spindle according to the second aspect of the patent application, wherein the upper end of the rotating shaft is provided with a first bearing which is an angular contact bearing, and the first bearing is respectively provided with a contact angle a first outer ring, a first inner ring and a first ball, and a first outer ring that is connected to the inner ends of the two first outer rings and the first inner ring is connected between the two first bearings a first inner spacer at the inner end, and a second bearing at the lower end of the shaft is provided with a second contact bearing, and a second outer ring and a second inner ring having a contact angle are respectively disposed on the second bearing And a second ball, and a second outer spacer ring connecting the inner ends of the two first outer rings and a second inner spacer ring contacting the inner ends of the two second inner rings are disposed between the two second bearings. The bearing preloading device of the machining spindle according to the first aspect of the invention, wherein the piston ring of the hydraulic mechanism is provided with an abutting edge for displacing the at least one bearing outer ring and changing the at least one bearing The contact angles of the outer ring, the ball and the inner ring cause the at least one bearing to generate a radial pre-pressure on the rotating shaft. The bearing preloading device for processing a spindle according to the first aspect of the invention, wherein the spindle sleeve is provided with a first flow passage and a second flow passage for respectively communicating with a buffer portion of the hydraulic chamber of the hydraulic mechanism and shifting And the first pressure regulating component is connected to the first flow channel, and the second flow channel is connected to the second pressure regulating component. The bearing preloading device of the processing spindle according to the seventh aspect of the invention, wherein the first pressure regulating component is provided with a first body, and the first body is provided with a first cavity, the first body One end of the first chamber communicates with the first flow passage of the spindle sleeve, and a first piston is disposed inside, and the other end is locked with a first stopper against the first piston. The bearing preloading device of the processing spindle according to the seventh aspect of the invention, wherein the second pressure regulating component is provided with a second body, and the second body is provided with a second cavity, the second body One end of the second chamber communicates with the second flow passage of the spindle sleeve, and a second piston is disposed inside, and the second end is locked with the second stopper. A resilient element is further disposed between the piston and the second stop to urge the second piston.