A cylindrical grinding headstock
By adopting a combination design of double-row angular contact bearings and single-row angular contact bearings in the headstock of the cylindrical grinding machine, the problem that traditional headstocks cannot clamp large workpieces has been solved, and stable machining and improved precision of carbide top hammers have been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- WUXI RUIZHI FANGDA METAL TECH DEV CO LTD
- Filing Date
- 2025-06-20
- Publication Date
- 2026-05-26
AI Technical Summary
Traditional cylindrical grinding headstocks cannot effectively clamp large workpieces, especially carbide top hammers, and during processing, excessive axial force can easily cause difficulty in rotation or prevent rotation.
The spindle employs a combination of double-row angular contact bearings (with a contact angle of 25°) and single-row angular contact bearings installed in opposite directions, along with a front and rear bearing sleeve design, to enhance the axial load capacity of the spindle and achieve stable rotation through a belt pulley drive system.
It significantly improves the clamping ability of large-size cemented carbide top hammers, enhances machining accuracy and equipment stability, extends equipment life, and reduces motor load.
Smart Images
Figure CN224274360U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of positioning for external cylindrical grinding of cemented carbide top hammer products, and in particular, it is a headstock for external cylindrical grinding. Background Technology
[0002] The outer diameter of the ejector hammer is ground using an external cylindrical grinding machine. During the grinding process, the ejector hammer needs to be centered and rotated at a uniform speed. Since the ejector hammer product does not have a center hole and is heavy, positioning can only be achieved by increasing the thrust of the tailstock of the grinding machine. The workpiece is clamped by the friction between the headstock spindle and the workpiece for grinding.
[0003] Using the headstock and tailstock of an external cylindrical grinder to clamp the workpiece directly is only suitable for small workpieces (products with a diameter of less than 165cm) and excessive force cannot be applied. This is because the positioning spindle of the headstock rotation mechanism is made of a bearing structure, which cannot withstand strong axial forces. The original design of the headstock axial positioning was achieved by the cooperation of a tapered bearing sleeve and a tapered spindle. When the axial force is too large, it will reduce the clearance of the tapered bearing sleeve, making the shaft difficult to rotate or even unable to rotate. Utility Model Content
[0004] In view of the above problems, the purpose of this application is to provide a headstock for an external cylindrical grinding machine, which can increase the axial force of small workpieces by several times, realize the clamping of large workpieces and enable them to rotate smoothly.
[0005] To achieve some or all of the above objectives or other objectives, this application provides the following technical solution: a cylindrical grinding headstock, comprising a housing and a top cover, wherein the housing and the top cover are provided with cavities; a second through hole and a first through hole are transversely arranged on the housing, penetrating the cavity, through which a headstock spindle is rotatably connected, the head of the headstock spindle being disposed near the first through hole; a front bearing sleeve is disposed in the first through hole, and a No. 1 bearing is disposed between the front bearing sleeve and the headstock spindle, the headstock spindle being fixedly installed in the inner ring of the No. 1 bearing with an interference fit; a rear bearing sleeve is disposed in the second through hole, and a No. 2 bearing is disposed between the rear bearing sleeve and the headstock spindle, the headstock spindle being fixedly installed in the inner ring of the No. 2 bearing with an interference fit.
[0006] Furthermore, the outer circumferential surface of the front bearing sleeve is provided with a first annular boss, which is fixedly connected to the housing by a first bolt; the outer circumferential surface of the front bearing sleeve is fitted with a front bearing sleeve, a bearing back cap, and a pulley bearing, which are located on the side of the first annular boss away from the second through hole; the pulley bearing is located between the first annular boss and the bearing back cap; a pulley is fitted on the outer ring of the pulley bearing; and an inner annular boss is provided on the inner circumferential surface of the pulley away from the second through hole.
[0007] Furthermore, it also includes a stop block; the outer peripheral surface of the head of the headstock spindle is provided with a spindle annular boss, the outer peripheral surface of the spindle annular boss contacts the inner peripheral surface of the inner annular boss of the pulley; the spindle annular boss is provided with a pin hole, the inner annular boss of the pulley is provided with a through hole matching the pin hole, the stop block is inserted into the pin hole through the through hole, and the stop block and the inner annular boss of the pulley are fixedly connected by a No. 2 bolt.
[0008] Furthermore, the head of the headstock spindle is provided with a blind hole, and a center is fixedly installed in the blind hole; the center is connected to one side of the top hammer pad, and the other side of the top hammer pad is provided with a pad annular boss for clamping the top hammer; the top hammer pad is provided with a limiting post on the side near the center, and the end face of the spindle annular boss near the top hammer pad is provided with a limiting groove, the limiting groove matching the limiting post, and one end of the limiting post being placed in the limiting groove.
[0009] Furthermore, it also includes a motor, which is located on the outside of the housing and connected to a motor pulley, the motor pulley being matched with the belt pulley.
[0010] Furthermore, the first bearing is a double-row angular contact bearing with a contact angle of 25°; the second bearing is a single-row angular contact bearing; and the front of the headstock spindle is designed with an outwardly expanding Morse taper No. 5.
[0011] Furthermore, a skeleton oil seal No. 1 and a front bearing sleeve back cap are also provided between the headstock spindle and the front bearing sleeve. The skeleton oil seal No. 1 is located on the side of the No. 1 bearing away from the second through hole. The front bearing sleeve back cap is located on the side of the No. 1 bearing close to the second through hole. The front bearing sleeve back cap abuts against the outer ring end face of the No. 1 bearing. The outer circumferential surface of the front bearing sleeve back cap is connected to the headstock spindle. A gap is provided between the inner circumferential surface of the front bearing sleeve back cap and the headstock spindle.
[0012] Furthermore, the front bearing sleeve is provided with radial oil holes and axial oil holes, and the center line of the radial oil hole intersects the center line of the axial oil hole perpendicularly.
[0013] Furthermore, the outer circumferential surface of the rear bearing sleeve is provided with a second annular boss, which is fixedly connected to the housing by a third bolt; a rear bearing sleeve back cap and a rear bearing sleeve inner back cap are also provided between the headstock spindle and the rear bearing sleeve; the rear bearing sleeve back cap is located on the side of the second bearing near the first through hole, abuts against the outer ring end face of the second bearing, the outer circumferential surface of the rear bearing sleeve back cap is connected to the rear bearing sleeve, and there is a gap between the inner circumferential surface of the rear bearing sleeve back cap and the headstock spindle; the rear bearing sleeve inner back cap is located on the side of the second bearing away from the first through hole, abuts against the inner ring end face of the second bearing, the inner circumferential surface of the rear bearing sleeve inner back cap is connected to the headstock spindle, and there is a gap between the outer circumferential surface of the rear bearing sleeve inner back cap and the rear bearing sleeve.
[0014] Furthermore, it also includes a rear dust cover, the rear dust cover having a Z-shaped cross-section, one end of the rear dust cover being sleeved on the headstock spindle, and a skeleton oil seal No. 2 being provided between one end of the rear dust cover and the headstock spindle; the other end of the rear dust cover being connected to the rear bearing sleeve.
[0015] Compared with existing technologies, the beneficial effects of this invention are as follows: By employing a combination of double-row angular contact bearings (contact angle of 25°) and single-row angular contact bearings installed in reverse, the axial load capacity of the spindle is significantly improved (up to 74KN), which can meet the clamping requirements of large-size carbide top hammers (diameter of 220mm and above), and solves the problem that traditional bearing structures cannot withstand large axial forces. This invention not only solves the technical problem that traditional cylindrical grinding machine headstocks cannot clamp large workpieces, but also significantly improves machining accuracy, stability, and equipment lifespan, demonstrating outstanding practicality and economic benefits. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the structure of this utility model;
[0017] Figure 2 This is a top view of the present invention;
[0018] Figure 3 AA view;
[0019] Figure 4 This is a front view of the present invention;
[0020] Figure 5 View for BB;
[0021] Figure 6 This is an enlarged schematic diagram of the first through hole;
[0022] Figure 7 This is an enlarged schematic diagram of the second through hole;
[0023] Figure 8 This is a schematic diagram of a top hammer;
[0024] In the diagram: 1. Rear bearing sleeve cap; 2. Top cover; 3. Motor; 4. Bolt No. 1; 5. Motor pulley; 6. Bearing No. 1; 7. Bolt No. 2; 8. Stop block; 9. Center; 10. Top hammer; 11. Top hammer pad; 1101. Pad annular boss; 1102. Limiting post; 12. Headstock spindle; 13. Bearing cap; 14. Pulley bearing; 15. Pulley; 1501. Pulley 16. Inner annular boss; 16. Front bearing sleeve; 1601. No. 1 annular boss; 17. Front bearing sleeve back cap; 18. Housing; 19. No. 3 bolt; 20. Rear bearing sleeve; 2001. No. 2 annular boss; 21. Rear dust cover; 22. Headstock spindle; 2201. Spindle annular boss; 2202. Limiting groove; 23. Inner back cap of bearing sleeve; 24. No. 2 skeleton oil seal; 25. No. 2 bearing. Detailed Implementation
[0025] To make the structure and function of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.
[0026] See appendix Figure 1-8 A cylindrical grinding headstock includes a housing 18 and a top cover 2, both containing cavities. The housing 18 has a second through hole and a first through hole extending horizontally through the cavity 100. A headstock spindle 22, rotatably connected to the headstock spindle 22, passes through the second and first through holes. The head of the headstock spindle 22 is positioned near the first through hole. A front bearing sleeve 16 is housed within the first through hole, and a first bearing 6 is positioned between the front bearing sleeve 16 and the headstock spindle 22. The headstock spindle 22 is fixedly mounted in the inner ring of the first bearing 6 with an interference fit. A rear bearing sleeve 20 is housed within the second through hole, and a second bearing 25 is positioned between the rear bearing sleeve 20 and the headstock spindle 22. The headstock spindle 22 is fixedly mounted in the inner ring of the second bearing 25 with an interference fit.
[0027] The headstock spindle is made of bearing steel with a quenched and tempered finish, possessing both toughness and strength, enabling it to withstand high-load conditions and ensuring the reliability of the equipment during long-term use. The bearings are made of P4 grade or higher precision and are slightly interference-fitted with the headstock spindle. Combined with the preload design of the front and rear bearing sleeves, the axial backlash of the spindle is effectively eliminated, ensuring high precision and stability during the grinding process.
[0028] The outer circumferential surface of the front bearing sleeve 16 is provided with a first annular boss 1601, which is fixedly connected to the housing 18 by a first bolt 4. A front bearing bush, bearing back cap 13, and pulley bearing 14 are fitted onto the outer circumferential surface of the front bearing sleeve 16. The front bearing bush, bearing back cap 13, and pulley bearing 14 are located on the side of the first annular boss 1601 away from the second through hole. The pulley bearing 14 is located between the first annular boss 1601 and the bearing back cap 13. A pulley 15 is fitted onto the outer ring of the pulley bearing 14. An inner annular boss 1501 is provided on the inner circumferential surface of the pulley 15 away from the second through hole. After the rolling bearing replaces the original bearing bush structure, the coefficient of friction is significantly reduced, allowing the headstock spindle to rotate easily even under large axial forces, reducing the motor load and improving the stability and efficiency of the grinding process.
[0029] It also includes a stop block 8; the outer peripheral surface of the head of the headstock spindle 22 is provided with a spindle annular boss 2201, the outer peripheral surface of the spindle annular boss 2201 is in contact with the inner peripheral surface of the inner annular boss 1501 of the pulley; the spindle annular boss 2201 is provided with a pin hole, the inner annular boss 1501 of the pulley is provided with a through hole that matches the pin hole, the stop block 8 is inserted into the pin hole through the through hole, and the stop block 8 and the inner annular boss 1501 of the pulley are fixedly connected by a No. 2 bolt 7.
[0030] The head of the headstock spindle 22 has a blind hole at its head, and a center 9 is fixedly installed in the blind hole. The center 9 is connected to one side of the top hammer pad 11, and the other side of the top hammer pad 11 has a pad annular boss 1101 for clamping the top hammer 10. The top hammer pad 11 has a limiting post 1102 near the center 9, and the end face of the spindle annular boss 2201 near the top hammer pad 11 has a limiting groove 2202. The limiting groove 2202 matches the limiting post 1102, and one end of the limiting post 1102 is placed in the limiting groove 2202. The pad annular boss 1101 has a groove that matches the edge of the top hammer 10. During rotation, the edge of the top hammer 10 is always in the groove, achieving clamping and positioning.
[0031] It also includes a motor 3, which is located on the outside of the housing 18. The motor 3 is connected to a motor pulley 5, which is matched with a pulley 15.
[0032] The first bearing 6 is a double-row angular contact bearing with a contact angle of 25°; the second bearing 25 is a single-row angular contact bearing installed in the opposite direction; the front of the headstock spindle 22 is designed with an outwardly flared Morse taper No. 5. By using a combination of double-row angular contact bearings (with a contact angle of 25°) and single-row angular contact bearings installed in the opposite direction, the axial load capacity of the spindle is significantly improved (up to 74KN), which can meet the clamping requirements of large-size carbide top hammers (diameter 220mm and above) and solve the problem that traditional bearing structures cannot withstand large axial forces.
[0033] A skeleton oil seal 12 and a front bearing sleeve back cap 17 are also provided between the headstock main shaft 22 and the front bearing sleeve 16. The skeleton oil seal 12 is located on the side of the first bearing 6 away from the second through hole. The front bearing sleeve back cap 17 is located on the side of the first bearing 6 close to the second through hole. The front bearing sleeve back cap 17 abuts against the outer ring end face of the first bearing 6. The outer circumferential surface of the front bearing sleeve back cap 17 is connected to the headstock main shaft 22. A gap is provided between the inner circumferential surface of the front bearing sleeve back cap 17 and the headstock main shaft 22.
[0034] The front bearing sleeve 16 is provided with radial oil holes and axial oil holes, with the center lines of the radial oil holes intersecting perpendicularly to the center lines of the axial oil holes. Through the design of the radial and axial oil holes on the front bearing sleeve, and the structure within the housing for storing lubricating oil, sufficient lubrication and cooling of the bearing are achieved, extending the bearing's service life and reducing maintenance frequency.
[0035] The outer circumferential surface of the rear bearing sleeve 20 is provided with a second annular boss 2001, which is fixedly connected to the housing 18 by a third bolt 19; a rear bearing sleeve back cap 1 and a rear bearing sleeve inner back cap 23 are also provided between the headstock spindle 22 and the rear bearing sleeve 20; the rear bearing sleeve back cap 1 is located on the side of the second bearing 25 near the first through hole, and the rear bearing sleeve back cap 1 abuts against the outer ring end face of the second bearing 25; the rear bearing sleeve... The outer circumferential surface of the back cap 1 is connected to the rear bearing sleeve 20, and there is a gap between the inner circumferential surface of the back cap 1 and the headstock main shaft 22; the inner back cap 23 of the rear bearing sleeve is located on the side of the second bearing 25 away from the first through hole, the inner back cap 23 of the rear bearing sleeve abuts against the inner ring end face of the second bearing 25, the inner circumferential surface of the inner back cap 23 of the rear bearing sleeve is connected to the headstock main shaft 22, and there is a gap between the outer circumferential surface of the inner back cap 23 of the rear bearing sleeve and the rear bearing sleeve 20.
[0036] It also includes a rear dust cover 21, which has a Z-shaped cross-section. One end of the rear dust cover 21 is fitted onto the headstock spindle 22, and a skeleton oil seal 24 is installed between one end of the rear dust cover 21 and the headstock spindle 22. The other end of the rear dust cover 21 is connected to the rear bearing sleeve 20. The design of the rear dust cover and the skeleton oil seal effectively prevents external impurities from entering the bearing, further ensuring the long-term stable operation of the bearing.
[0037] Transmission process: Motor 3 transmits power to pulley 15 via belt, and then the stop block 8 at the end of pulley 15 transmits the rotational force to the headstock spindle 22. The headstock spindle 22 is fixed by two bearing sleeves, front and rear, with angular contact bearings installed inside. The bearing sleeves have oil passages to ensure lubrication, and the other end of the bearing sleeve is fixed to the housing to prevent transmission. The rotational force is then transmitted to the Morse taper #5 through the headstock spindle 22. The taper's function is to stabilize the center. The rotational force is driven by two screws at the end of the headstock spindle 22, which drive the top hammer pad 11, and finally transmitted to the workpiece top hammer 10, thus realizing external cylindrical grinding.
[0038] The above-disclosed embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of this application. Therefore, any equivalent variations made in accordance with the claims of this application shall still fall within the scope of this application.
Claims
1. A headstock for an external cylindrical grinding machine, characterized in that: The device includes a housing (18) and a top cover (2), both of which have cavities. The housing (18) has a second through hole and a first through hole that pass through the cavity (100) laterally. A head frame spindle (22) that is rotatably connected passes through the second through hole and the first through hole. The head of the head frame spindle (22) is positioned close to the first through hole. A front bearing sleeve (16) is provided in the first through hole. A first bearing (6) is provided between the front bearing sleeve (16) and the head frame spindle (22). The head frame spindle (22) is fixedly installed in the inner ring of the first bearing (6) with an interference fit. A rear bearing sleeve (20) is provided in the second through hole. A second bearing (25) is provided between the rear bearing sleeve (20) and the head frame spindle (22). The head frame spindle (22) is fixedly installed in the inner ring of the second bearing (25) with an interference fit.
2. The cylindrical grinding headstock according to claim 1, characterized in that: The outer circumferential surface of the front bearing sleeve (16) is provided with a first annular boss (1601), and the first annular boss (1601) is fixedly connected to the housing (18) by a first bolt (4); the outer circumferential surface of the front bearing sleeve (16) is fitted with a front bearing sleeve, a bearing back cap (13) and a pulley bearing (14), the front bearing sleeve, the bearing back cap (13) and the pulley bearing (14) are located on the side of the first annular boss (1601) away from the second through hole, the pulley bearing (14) is located between the first annular boss (1601) and the bearing back cap (13), the outer ring of the pulley bearing (14) is fitted with a pulley (15), and the inner circumferential surface of the pulley (15) is provided with an inner annular boss (1501) on the side away from the second through hole.
3. The cylindrical grinding headstock according to claim 2, characterized in that: It also includes a stop block (8); the outer peripheral surface of the head of the head frame spindle (22) is provided with a spindle annular boss (2201), the outer peripheral surface of the spindle annular boss (2201) is in contact with the inner peripheral surface of the inner annular boss (1501) of the pulley; the spindle annular boss (2201) is provided with a pin hole, the inner annular boss (1501) of the pulley is provided with a through hole that matches the pin hole, the stop block (8) is inserted into the pin hole through the through hole, and the stop block (8) and the inner annular boss (1501) of the pulley are fixedly connected by a No. 2 bolt (7).
4. The headstock of an external cylindrical grinding machine according to claim 3, characterized in that: The head of the headstock spindle (22) is provided with a blind hole, and a tip (9) is fixedly installed in the blind hole; the tip (9) is connected to one side of the top hammer pad (11), and the other side of the top hammer pad (11) is provided with a pad annular boss (1101) for clamping the top hammer (10); the top hammer pad (11) is provided with a limiting post (1102) on the side near the tip (9), and the spindle annular boss (2201) is provided with a limiting groove (2202) on the end face near the top hammer pad (11), the limiting groove (2202) matches the limiting post (1102), and one end of the limiting post (1102) is placed in the limiting groove (2202).
5. A cylindrical grinding headstock according to claim 2, characterized in that: It also includes a motor (3), which is located on the outside of the housing (18). The motor (3) is connected to a motor pulley (5), which is matched with the pulley (15).
6. The headstock of an external cylindrical grinding machine according to claim 1, characterized in that: The first bearing (6) is a double-row angular contact bearing with a contact angle of 25°; the second bearing (25) is a single-row angular contact bearing; the front of the headstock spindle (22) is set with an outwardly expanding Morse taper No.
5.
7. The headstock of an external cylindrical grinding machine according to claim 1, characterized in that: A skeleton oil seal No. 1 (12) and a front bearing sleeve back cap (17) are also provided between the head frame main shaft (22) and the front bearing sleeve (16). The skeleton oil seal No. 1 (12) is located on the side of the No. 1 bearing (6) away from the second through hole. The front bearing sleeve back cap (17) is located on the side of the No. 1 bearing (6) close to the second through hole. The front bearing sleeve back cap (17) abuts against the outer ring end face of the No. 1 bearing (6). The outer circumferential surface of the front bearing sleeve back cap (17) is connected to the head frame main shaft (22). There is a gap between the inner circumferential surface of the front bearing sleeve back cap (17) and the head frame main shaft (22).
8. The headstock of an external cylindrical grinding machine according to claim 1, characterized in that: The front bearing sleeve (16) is provided with radial oil holes and axial oil holes, and the center line of the radial oil hole intersects the center line of the axial oil hole perpendicularly.
9. A cylindrical grinding headstock according to claim 1, characterized in that: The outer circumferential surface of the rear bearing sleeve (20) is provided with a second annular boss (2001), and the second annular boss (2001) is fixedly connected to the housing (18) by a third bolt (19); a rear bearing sleeve back cap (1) and a rear bearing sleeve inner back cap (23) are also provided between the headstock spindle (22) and the rear bearing sleeve (20); the rear bearing sleeve back cap (1) is provided on the side of the second bearing (25) near the first through hole, and the rear bearing sleeve back cap (1) abuts against the outer ring end face of the second bearing (25), and the rear bearing sleeve... The outer circumferential surface of the sleeve cap (1) is connected to the rear bearing sleeve (20), and there is a gap between the inner circumferential surface of the rear bearing sleeve cap (1) and the head frame main shaft (22); the inner circumferential cap (23) of the rear bearing sleeve is located on the side of the second bearing (25) away from the first through hole, the inner circumferential cap (23) of the rear bearing sleeve abuts against the inner ring end face of the second bearing (25), the inner circumferential surface of the inner circumferential cap (23) of the rear bearing sleeve is connected to the head frame main shaft (22), and there is a gap between the outer circumferential surface of the inner circumferential cap (23) of the rear bearing sleeve and the rear bearing sleeve (20).
10. A cylindrical grinding headstock according to claim 1, characterized in that: It also includes a rear dust cover (21), the cross-section of which is Z-shaped. One end of the rear dust cover (21) is sleeved on the head frame main shaft (22), and a skeleton oil seal No. 2 (24) is provided between one end of the rear dust cover (21) and the head frame main shaft (22); the other end of the rear dust cover (21) is connected to the rear bearing sleeve (20).