A hydraulic buffer device for a center frame of a heavy machine tool

Abstract

The present invention discloses a hydraulic buffer device for a center frame of a heavy machine tool; the buffer device comprises a center frame base, a hydraulic buffer supporting mechanism and an adjusting mechanism; wherein the hydraulic buffer supporting mechanism is arranged on the center frame base, and comprises an adjustable supporting piece and a hydraulic buffer seat; the adjustable supporting piece is columnar and slidably cooperates with the center frame base, and the hydraulic buffer seat is fixed on the center frame base and supported on the end of the adjustable supporting piece; the adjusting mechanism is arranged on the center frame base and acts on the adjustable supporting piece; the present invention can buffer the force brought by the workpiece after the adjustable supporting piece instantaneously bears the load, effectively avoids the wear of the screw rod and nut components, and increases the service life of the center frame.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical processing, and in particular relates to a hydraulic buffer device for a center frame of a heavy machine tool. Background Art

[0002] At present, the center frame of the machine tool uses a nut and a lead screw to achieve the auxiliary support function of the workpiece. On small and light machine tools, the weight of the workpiece is relatively light, and the damage to the nut and the lead screw is relatively slight, which will not affect the use of the center frame. However, on heavy machine tools, due to the heavy weight of the workpiece (the machine tool load-bearing capacity is greater than 63 tons), when the workpiece is clamped, the weight of the workpiece is mainly borne by the adjustable top holding parts on the base of the center frame, and the nut and the lead screw have to bear a larger weight; when the center frame instantly bears the weight of the workpiece, it will cause the lead screw and nut to deform, thus affecting the use. Summary of the invention

[0003] The purpose of the present invention is to provide a hydraulic buffer device for a heavy machine tool center frame in view of the deficiencies in the prior art, which can provide buffering after the adjustable top holding part bears load instantaneously, thereby effectively avoiding wear of the screw rod and nut components.

[0004] To achieve the above object, the technical solution adopted by the present invention is:

[0005] A hydraulic buffer device for a center frame of a heavy machine tool, comprising:

[0006] Center frame base;

[0007] A hydraulic buffer support mechanism, which is arranged on the center frame base, and includes an adjustable support member and a hydraulic buffer seat; the adjustable support member is columnar and slidably cooperates with the center frame base, and the hydraulic buffer seat is fixed on the center frame base and supports the end of the adjustable support member; and

[0008] The adjusting mechanism is arranged on the center frame base and acts on the adjustable top holding member.

[0009] Further, the adjustable top holding member comprises:

[0010] The top holding head is columnar and has a contact for contacting the workpiece at one end and a screw rod with a different diameter from the top holding head at the other end. The top holding head is slidably matched with the center frame base;

[0011] The gear sleeve comprises a sleeve which is slidably matched with the center frame base and a first gear arranged outside the sleeve, wherein the sleeve is sleeved outside the screw rod;

[0012] A nut sleeve, which is fixed to the inner side of one end of the sleeve and cooperates with the screw rod; and

[0013] The end seat is arranged at the other end of the sleeve and is slidably matched with the center frame base.

[0014] Further, the hydraulic buffer seat comprises:

[0015] A hydraulic cylinder is fixed on the center frame base and corresponds to the bottom of the end seat, and a back pressure valve is provided on the oil discharge pipeline of the hydraulic cylinder;

[0016] The rotating seat is arranged at the end of the hydraulic cylinder and supported on the end seat.

[0017] Furthermore, the hydraulic cylinder includes a cylinder body, a flange plate arranged at the end of the cylinder body, a piston matched with the cylinder body, and a piston rod arranged on the piston and extending to the outside of the cylinder body through the flange plate; the free end of the piston rod is in the shape of a stepped shaft and is formed with a large diameter shaft section, a medium diameter shaft section and a small diameter shaft section.

[0018] Furthermore, the rotating seat includes a thrust roller bearing, a top block and a deep groove ball bearing; the thrust roller bearing is sleeved on the large diameter shaft section of the free end of the piston rod, the top block is sleeved on the medium diameter shaft section of the free end of the piston rod and covers the thrust roller bearing, and the deep groove ball bearing is installed between the small diameter shaft section of the free end of the piston rod and the inner wall of the top block.

[0019] Furthermore, the adjustment mechanism includes a first transmission shaft arranged parallel to the axis of the gear sleeve and hinged on the base of the central frame, a second gear arranged on the first transmission shaft and meshing with the first gear, a third gear arranged on the first transmission shaft, a fourth gear meshing with the third gear, and a second transmission shaft hinged on the base of the central frame and fixedly connected to the fourth gear; one end of the second transmission shaft extends outside the base of the central frame, the tooth width of the second gear is greater than that of the first gear, and a limit stop plate is provided on one side of the second gear, and the limit stop plate acts on one side of the first gear.

[0020] The beneficial effects of the present invention are:

[0021] 1. The structural design of the present invention enables the adjustable top holding member for holding the workpiece to slide relative to the center frame as a whole, so that the hydraulic buffer seat can form a buffering effect on the adjustable top holding member as a whole, thereby effectively avoiding deformation and damage between the screw rod and the nut sleeve; at the same time, the adjustable top holding member can also realize its own telescopic adjustment through the adjustment mechanism, thereby realizing the workpiece alignment operation;

[0022] 2. In the structural design of the present invention, a back pressure valve is arranged on the hydraulic cylinder oil discharge pipeline, and the back pressure valve is used to release pressure to buffer the force of the workpiece on the adjustable top holding member. The buffering is stable and safe, and the buffering force is adjustable. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the present invention.

[0024] Among them: 1-center frame base; 2-adjustable top holding piece; 3-hydraulic buffer seat; 4-top holding head; 5-contact; 6-screw rod; 7-gear sleeve; 8-sleeve; 9-first gear; 10-nut sleeve; 11-end seat; 12-hydraulic cylinder; 13-swivel seat; 14-cylinder body; 15-flange; 16-piston; 17-piston rod; 18-thrust roller bearing; 19-top block; 20-deep groove ball bearing; 21-first transmission shaft; 22-second gear; 23-third gear; 24-fourth gear; 25-second transmission shaft; 26-limit plate; 27-sliding bearing. DETAILED DESCRIPTION

[0025] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings:

[0026] like Figure 1 As shown, a hydraulic buffer device for a center frame of a heavy machine tool mainly includes a center frame base 1, a hydraulic buffer support mechanism and an adjustment mechanism. The center frame usually includes a center frame upper body and a center frame base 1. The support member on the center frame base 1 is the main bearing member of the workpiece, and the support member here is also the most vulnerable to damage. The improvement of the present invention is mainly aimed at the support member at this location, so that the support member at this location can be buffered after instantaneous bearing, thereby achieving the purpose of protecting the support member.

[0027] The center frame base 1 provides support for the hydraulic buffer support mechanism. The center frame base 1 is provided with a sliding member for the hydraulic buffer support mechanism to slide, and a storage space for the hydraulic buffer support mechanism to perform actions during alignment operation. For the specific structure, please refer to the structure shown in the attached drawings.

[0028] The hydraulic buffer support mechanism is arranged on the center frame base 1; the hydraulic buffer support mechanism includes an adjustable support member 2 and a hydraulic buffer seat 3; the adjustable support member 2 is columnar and slidably cooperates with the center frame base 1, and the adjustable support member 2 as a whole can slide relative to the center frame base 1, so that after the adjustable support member 2 is instantaneously loaded, it can cooperate with the hydraulic buffer seat 3 to achieve a buffering effect; the hydraulic buffer seat 3 is fixed on the center frame base 1 and supports the end of the adjustable support member 2.

[0029] Specifically, the adjustable top holding member 2 includes a top holding head 4, a gear sleeve 7, a nut sleeve 10 and an end seat 11; the top holding head 4 is columnar and has a contact 5 for contacting a workpiece at one end and a screw 6 with a different diameter from the top holding head 4 at the other end, and the screw 6 is smaller than the diameter of the top holding head 4; the top holding head 4 is slidably matched with the center frame base 1, specifically in an axis / hole matching manner, and the axial movement of the top holding head 4 is guided by a matching slideway on the center frame base 1; the gear sleeve 7 includes a sleeve 8 slidably matched with the center frame base 1 and a first gear 9 arranged on the outside of the sleeve 8; the sleeve 8 relies on the matching slideway on the center frame base 1 to provide guidance during axial movement, and the sleeve 8 The sleeve 8 can realize circumferential rotation relative to the center frame base 1, and the sleeve 8 is sleeved on the outside of the screw rod 6; the nut sleeve 10 is fixed on the inner side of one end of the sleeve 8 and cooperates with the screw rod 6, and the rotation of the sleeve 8 can drive the nut sleeve 10 to rotate synchronously; the end seat 11 is arranged at the other end of the sleeve 8 and slides with the center frame base 1. The end seat 11 and the other end of the sleeve 8 can be fixed by bolts. The end seat 11 and the sleeve 8 need to rotate synchronously and move axially synchronously. In order to reduce friction resistance, a sliding bearing 27 can be added to the outside of the joint between the end seat 11 and the sleeve 8. After the friction resistance is reduced, it is also convenient for the adjustment mechanism to apply force to drive the sleeve 8 to rotate, thereby reducing the resistance of the adjustment operation of the adjustment mechanism.

[0030] Specifically, the hydraulic buffer seat 3 includes a hydraulic cylinder 12 and a rotating seat 13; the hydraulic cylinder 12 is fixed on the center frame base 1 and corresponds to the bottom of the end seat 11; a back pressure valve is provided on the oil discharge pipeline of the hydraulic cylinder 12. When the pressure on the hydraulic cylinder 12 reaches a certain value, the hydraulic oil can be automatically discharged through the back pressure valve, thereby achieving the purpose of pressure relief and buffering. The hydraulic cylinder 12 can be connected to the hydraulic system of the machine tool for control, and can also be connected to an external hydraulic system for control, such as an external hydraulic station for hydraulic control; the hydraulic cylinder 12 specifically includes a cylinder body 14, a flange 15 provided at the end of the cylinder body 14, a piston 16 matched with the cylinder body 14, and a piston rod 17 provided on the piston 16 and extending to the outside of the cylinder body 14 through the flange 15; the cylinder body 14 is fixed to the center frame base 1 by bolts, and the flange 15 is fixed to the end of the cylinder body 14 by bolts; the free end of the piston rod 17 is The processing makes it into a stepped shaft shape, and forms a large diameter shaft section, a medium diameter shaft section and a small diameter shaft section, which is convenient for matching with the rotating seat 13; the rotating seat 13 is arranged at the end of the hydraulic cylinder 12 and supported on the end seat 11; the rotating seat 13 specifically includes a thrust roller bearing 18, a top block 19 and a deep groove ball bearing 20; the thrust roller bearing 18 is sleeved on the large diameter shaft section at the free end of the piston rod 17, the top block 19 is cylindrical and the inner wall is stepped, the top block 19 is sleeved on the medium diameter shaft section at the free end of the piston rod 17 and presses the thrust roller bearing 18, and the deep groove ball bearing 20 is installed between the small diameter shaft section at the free end of the piston rod 17 and the inner wall of the top block 19. The rotating seat 13 can use the thrust roller bearing 18 to bear the axial load, and at the same time, the matching deep groove ball bearing 20 can ensure that the rotating seat 13 rotates smoothly in the circumferential direction, and the resistance effect of the synchronous rotation of the rotating seat 13 and the end seat 11 on the end seat 11 can be reduced.

[0031] The adjusting mechanism is used to control the rotation of the adjustable supporting member 2. The adjusting mechanism is arranged on the center frame base 1 and acts on the first gear 9 of the adjustable supporting member 2. The adjusting mechanism includes a first transmission shaft 21 arranged parallel to the axis of the gear sleeve 7 and hinged on the center frame base 1, a second gear 22 arranged on the first transmission shaft 21 and meshing with the first gear 9, a third gear 23 arranged on the first transmission shaft 21, a fourth gear 24 meshing with the third gear 23, and a second transmission shaft 25 hinged on the center frame base 1 and fixedly connected to the fourth gear 24; both ends of the first transmission shaft 21 are hinged to the center frame base 1 through bearings, and the lower end of the first transmission shaft 21 is equipped with an end cover, which is connected to the center frame base 1, so as to facilitate the assembly of the first transmission shaft 21; the first gear 9 and the second gear 22 are both spur gears; the second gear 22 A limit stop plate 26 is provided on the upper side, and the limit stop plate 26 is screwed and fixed on the side of the second gear 22. The limit stop plate 26 acts on one side of the first gear 9. The limit stop plate 26 can limit the first gear 9 to prevent the first gear 9 from disengaging from the second gear 22 during axial movement; the tooth width of the second gear 22 is greater than the first gear 9, which can provide a certain range of motion for the axial movement of the first gear 9; the third gear 23 and the fourth gear 24 are bevel gears, which are used to change the action position of the second transmission shaft 25. The second transmission shaft 25 is hinged in a cylinder through a bearing, and the cylinder is fixed on the center frame base 1; one end of the second transmission shaft extends outside the center frame base, and the rotation of the second transmission shaft 25 can be manually controlled by cooperating with one end of the second transmission shaft 25 through an external hand wheel or an operating lever, or it can be automatically controlled by an external reduction motor.

[0032] The working principle of the present invention is as follows: first, the hydraulic system is used to control the hydraulic cylinder 12 to move, so that the rotating seat 13 supports the end seat 11 to move, thereby realizing the overall movement of the adjustable top holding member 2 relative to the center frame base 1 until the contact 5 contacts the workpiece; then the hanger or other temporary supporting device of the workpiece is released, and the workpiece will instantly act on the adjustable top holding member 2. When the force is greater than the set value of the back pressure valve, the back pressure valve opens, the hydraulic cylinder 12 discharges oil, and the workpiece presses the adjustable top holding member 2 downward, thereby buffering a part of the force of the workpiece. This can avoid that the entire force of the workpiece acts instantaneously between the screw rod 6 and the nut sleeve 10, thereby protecting the screw rod 6 and the nut sleeve 10. Since the back pressure valve has the characteristic of adjustable pressure, the back pressure valve opening pressure can be appropriately adjusted according to the weight of the workpiece; when the buffering of the hydraulic cylinder 12 is completed, the piston 16 is located at the bottom of the cylinder body 14, and the adjustable top holding member 2 stops downward; at this time, the workpiece alignment operation can be performed, and during the alignment operation process In the embodiment, the fine adjustment of the holding head 4 is achieved by rotating the second transmission shaft 25; the principle of fine adjustment of the holding head 4 is: when the second transmission shaft 25 rotates, the first transmission shaft 21 is driven to rotate by the cooperation of the fourth gear 24 and the third gear 23, and the first transmission shaft 21 drives the sleeve 8 to rotate by the cooperation of the second gear 22 and the first gear 9, and the sleeve 8 drives the nut sleeve 10 to rotate, and the nut sleeve 10 cooperates with the screw rod 6. At the same time, the holding head 4 is squeezed by the workpiece and stopped circumferentially, and the nut sleeve 10 can be used to drive the screw rod 6 to move axially, thereby realizing the adjustment of the workpiece by the holding head 4.

Claims

1. A hydraulic buffer device for a center frame of a heavy machine tool, characterized in that: include: A center frame base (1), wherein the center frame base (1) is provided with a hydraulic buffer support mechanism and an adjustment mechanism; the hydraulic buffer support mechanism comprises an adjustable support member (2) and a hydraulic buffer seat (3); The adjustable supporting member (2) is columnar and is slidably matched with the center frame base (1). The adjustable supporting member (2) comprises a supporting head (4), a gear sleeve (7), a nut sleeve (10) and an end seat (11); the supporting head (4) is columnar and is provided with a contact (5) for contacting a workpiece at one end and a screw (6) of a different diameter from the supporting head (4) at the other end, and the supporting head (4) is slidably matched with the center frame base (1); the gear sleeve (7) comprises a sleeve (8) slidably matched with the center frame base (1) and a first gear (9) arranged on the outside of the sleeve (8), and the sleeve (8) is sleeved on the outside of the screw (6); the nut sleeve (10) is fixed on the inner side of one end of the sleeve (8) and is matched with the screw (6); the end seat (11) is arranged at the other end of the sleeve (8) and is slidably matched with the center frame base (1); The hydraulic buffer seat (3) is fixed on the center frame base (1) and supported on the end of the adjustable supporting member (2); the hydraulic buffer seat (3) comprises a hydraulic cylinder (12) and a rotating seat (13); the hydraulic cylinder (12) is fixed on the center frame base (1) and corresponds to the bottom of the end seat (11), and a back pressure valve is provided on the oil discharge pipeline of the hydraulic cylinder (12); the rotating seat (13) is provided at the end of the hydraulic cylinder (12) and supported on the end seat (11); The adjusting mechanism acts on the adjustable supporting member (2), and comprises a first transmission shaft (21), a second transmission shaft (25), a first gear (9), a second gear (22), a third gear (23) and a fourth gear (24).

2. A hydraulic buffer device for a center frame of a heavy machine tool as claimed in claim 1, characterized in that: The hydraulic cylinder (12) comprises a cylinder body (14), a flange (15) arranged at the end of the cylinder body (14), a piston (16) matched with the cylinder body (14), and a piston rod (17) arranged on the piston (16) and extending to the outside of the cylinder body (14) through the flange (15); the free end of the piston rod (17) is in the shape of a stepped shaft and is formed with a large diameter shaft section, a medium diameter shaft section and a small diameter shaft section.

3. A hydraulic buffer device for a center frame of a heavy machine tool as claimed in claim 2, characterized in that: The rotating seat (13) comprises a thrust roller bearing (18), a top block (19) and a deep groove ball bearing (20); the thrust roller bearing (18) is sleeved on the large diameter shaft section at the free end of the piston rod (17); the top block (19) is sleeved on the medium diameter shaft section at the free end of the piston rod (17) and covers the thrust roller bearing (18); and the deep groove ball bearing (20) is installed between the small diameter shaft section at the free end of the piston rod (17) and the inner wall of the top block (19).

4. A hydraulic buffer device for a center frame of a heavy machine tool as claimed in claim 3, characterized in that: The adjustment mechanism comprises a first transmission shaft (21) arranged parallel to the axis of the gear sleeve (7) and hinged on the center frame base (1), a second gear (22) arranged on the first transmission shaft (21) and meshing with the first gear (9), a third gear (23) arranged on the first transmission shaft (21), a fourth gear (24) meshing with the third gear (23), and a second transmission shaft (25) hinged on the center frame base (1) and fixedly connected to the fourth gear (24); one end of the second transmission shaft (25) extends outside the center frame base (1), the tooth width of the second gear (22) is greater than that of the first gear (9), and a limit stop plate (26) is provided on one side of the second gear (22), and the limit stop plate (26) acts on one side of the first gear (9).

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