Floating pressing mechanism capable of automatically returning

Abstract

The utility model discloses a floating hold-down mechanism capable of automatically aligning, which comprises a piston leveling and aligning structure and a floating hold-down structure, the piston leveling and aligning structure comprises a piston cavity, a piston ejector rod, a piston cavity end cover, a cylindrical spring, a leveling fastening rod and the like, and when compressed air is introduced, the piston cavity end cover is fixed on the piston cavity end cover. The piston ejector rod can be pushed out and withdrawn, and automatic return of the rotating shaft is achieved; the floating pressing mechanism comprises a mounting shell, a thrust self-aligning ball bearing, a bearing nut, a self-aligning ball bearing, a rotating shaft, a bearing end cover and the like, the thrust self-aligning ball bearing, the self-aligning ball bearing and the bearing nut are jointly mounted on the rotating shaft, and the rotating shaft can rotate and swing around the ball centers of the thrust self-aligning ball bearing and the bearing nut and has certain floatability. The hydraulic clamp is compact in structure, high in rotation precision and capable of effectively solving the problem that a workpiece is pressed to be deviated due to inclination of a piston of the pressing cylinder in the hydraulic clamp.

Description

Technical Field

[0001] The utility model belongs to the field of hydraulic clamps, and particularly relates to a floating clamping mechanism capable of automatically returning to the center. Background Art

[0002] Hydraulic clamps are clamps that use hydraulic components to replace mechanical parts and realize automatic positioning, support and clamping of workpieces through hydraulic control. They have the advantages of strong clamping force, reliable clamping, stable operation and easy use, and are widely used in CNC machine tools, machining centers, automated production lines and other scenarios.

[0003] The clamping cylinder is a key component that provides clamping force in the hydraulic clamp. Usually, the selected clamping cylinder is connected to the designed clamping mechanism through a clamping arm to obtain the required clamp. However, due to the gap between the piston of the clamping cylinder and the cylinder wall, when the end of the clamping arm is subjected to a large force, a bending moment will be generated, causing the piston to tilt in the cylinder, resulting in the workpiece being pressed off and affecting the processing accuracy. For example, Chinese patent CN 210147553 U discloses a special clamp for impeller processing, which is characterized by: comprising a main shaft, a positioning block, an air distribution cushion block, a clamping cylinder, a clamping arm and a centering mandrel, a clamping arm is provided on the top of the clamping cylinder, one end of the clamping arm is connected to the clamping cylinder, and a rotating disk is installed on the other end. When the clamping arm clamps the impeller, the clamping arm is bound to bend, causing the rotating disk to deviate from the rotation center of the main shaft, thereby affecting the processing accuracy.

[0004] The utility model solves the problem that the clamping cylinder piston is tilted and causes the workpiece to be pressed off-center by designing the clamping mechanism at the end of the clamping arm as a floating structure that can automatically return to the center, so that the inclination of the clamping arm caused by the piston can be offset, thereby ensuring that the clamping mechanism is tightly fitted to the upper end surface of the workpiece. Utility Model Content

[0005] The utility model aims to provide a floating clamping mechanism which has compact structure, high rotation accuracy and can automatically return to the center.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A floating clamping mechanism capable of automatically returning to the center comprises a piston leveling and returning structure consisting of a piston cavity 2, a piston push rod 3, a first sealing ring 4, a piston cavity end cover 5, and a cylindrical spring 6, and a floating clamping structure consisting of an installation housing 1, a thrust self-aligning ball bearing 7, a second sealing ring 8, a bearing nut 9, a self-aligning ball bearing 10, a rotating shaft 11, a dustproof sealing ring 12, a leveling and fastening rod 13, a flat pressure head 14, and a bearing end cover 15; the piston leveling and returning structure is connected to the floating clamping structure by screws.

[0008] The piston cavity 2 is designed with an air inlet hole 2-1, an upper cavity 2-2, a lower cavity 2-3, and a mounting countersunk hole 2-4, and the air inlet hole 2-1 is connected to the upper cavity 2-2; a first sealing ring 4 is installed on the piston top rod 3, dividing the interior of the piston cavity 2 into an upper cavity 2-2 and a lower cavity 2-3; a cylindrical spring 6 is sleeved on the piston top rod 3 and installed in the piston cavity end cover 5, and the piston cavity end cover 5 is nested in the piston cavity 2 and connected to the mounting shell 1 through the mounting countersunk hole 2-4 with screws.

[0009] The thrust self-aligning ball bearing 7 and the self-aligning ball bearing 10 are installed on the same rotating shaft 11. By reasonably designing the thickness of the bearing nut 9, the centers of the thrust self-aligning ball bearing 7 and the self-aligning ball bearing 10 are at the same position, and the rotating shaft 11 can swing around the centers of the thrust self-aligning ball bearing 7 and the self-aligning ball bearing 10; the bearing nut 9 cooperates with the thread 11-3 on the rotating shaft 11.

[0010] Furthermore, when compressed air of a certain pressure and flow rate is introduced into the air inlet 2-1, the compressed air enters the upper cavity 2-2, generates pressure on the upper end surface of the piston push rod 3, and pushes the piston push rod 3 to move downward along the inner wall of the piston cavity 2. The cylindrical spring 6 will produce a certain amount of compression, and at the same time, the piston push rod conical surface 3-1 of the piston push rod 3 and the tapered hole matching surface 13-1 contact each other, forcing the leveling and fastening rod 13 to be coaxial with the piston push rod 3. At the same time, the cylindrical matching surface 13-2 of the leveling and fastening rod 13 is tightly matched with the first cylindrical hole mounting surface 11-1 of the rotating shaft 11, thereby driving the rotating shaft 11 to be coaxial with the piston push rod 3. At the same time, the second cylindrical hole mounting surface 11-6 of the rotating shaft 11 is tightly matched with the flat pressure head 14, and is installed and fixed by the connecting thread 13-3 of the leveling and fastening rod 13, so that the bottom surface of the flat pressure head 14 is perpendicular to the axis of the piston push rod 3.

[0011] Furthermore, when the air inlet 2-1 removes the compressed air from the upper cavity 2-2, the piston push rod 3 moves upward under the action of the cylindrical spring 6, and the piston push rod conical surface 3-1 is no longer in contact with the conical hole matching surface 13-1.

[0012] Furthermore, the mounting housing 1 is designed with a lubrication oil filling port 1-1 and a lubrication channel 1-2. The lubrication oil filling port 1-1 and the lubrication channel 1-2 are connected. When grease is introduced from the lubrication oil filling port 1-1, the grease enters the interior of the mounting housing 1 and the bearing end cover 15 through the lubrication channel 1-2 to lubricate the thrust self-aligning ball bearing 7 and the self-aligning ball bearing 10.

[0013] Furthermore, an annular groove is designed on the mounting shell 1 for installing a second sealing ring 8, which is used to prevent grease leakage; a threaded mounting hole 15-1 and a dust ring groove 15-2 are designed on the bearing end cover 15, which is connected to the mounting shell 1 through the threaded mounting hole 15-1 with screws, and the dust ring groove 15-2 is used to install a dust seal 12, which can prevent external dust from entering on the one hand, and prevent grease from leaking from the dust cylindrical surface 11-5 of the rotating shaft 11 on the other hand.

[0014] Compared with the prior art, the utility model has the following technical effects:

[0015] 1) The utility model adopts the thrust self-aligning ball bearing and the self-aligning ball bearing to work together, which not only ensures the rotation accuracy of the shaft, but also improves the load-bearing capacity of the clamping mechanism;

[0016] 2) The utility model adopts a thrust self-aligning ball bearing and a self-aligning ball bearing installed on the same rotating shaft, and by adjusting the thickness of the bearing nut, the rotating ball centers of the two are located at the same position, so that the rotating shaft has a certain range of floating property, which can ensure that the axis of the rotating shaft is always perpendicular to the pressing surface of the workpiece, which is more conducive to ensuring the processing accuracy;

[0017] 3) The utility model adopts a piston leveling and returning structure, which can timely adjust the shaft return to the center, ensuring that the axis of the shaft is perpendicular to the workpiece pressing surface before the clamping mechanism is pressed down each time, and the energy used is compressed air, which is clean and pollution-free, protecting the environment to the greatest extent and practicing green manufacturing;

[0018] 4) The piston leveling and returning structure and the floating pressing structure adopted in the utility model ensure that the axis of rotation of the rotating shaft is kept at the same position before pressing the workpiece each time. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0020] Figure 1 It is a schematic cross-sectional view of the front view of the utility model;

[0021] Figure 2 This is a cross-sectional schematic diagram of the piston leveling and returning structure of the utility model rotated 45 degrees;

[0022] Figure 3 is a schematic cross-sectional view of the main view of the rotating shaft;

[0023] Figure 4 is a schematic cross-sectional view of a front view of a leveling and tightening rod;

[0024] Figure 5 It is a cross-sectional schematic diagram of the bearing end cover structure rotated 45 degrees;

[0025] Among them: 1-installation housing, 1-1-lubrication oil filling port, 1-2-lubrication channel, 2-piston cavity, 2-1-air inlet, 2-2-upper cavity, 2-3-lower cavity, 2-4-installation countersunk hole, 3-piston push rod, 3-1-piston push rod cone, 4-first sealing ring, 5-piston cavity end cover, 6-cylindrical spring, 7-thrust self-aligning ball bearing, 8-second sealing ring, 9-bearing nut, 10-self-aligning ball bearing, 11-rotating shaft, 11-1 -first cylindrical hole mounting surface, 11-2-first bearing mounting surface, 11-3-thread, 11-4-second bearing mounting surface, 11-5-dustproof cylindrical surface, 11-6-second cylindrical hole mounting surface, 12-dustproof sealing ring, 13-leveling fastening rod, 13-1-taper hole matching surface, 13-2-cylindrical matching surface, 13-3-connecting thread, 14-flat pressure head, 15-bearing end cover, 15-1-threaded mounting hole, 15-2-dustproof ring groove. DETAILED DESCRIPTION

[0026] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict.

[0027] The following detailed descriptions are all exemplary descriptions, and are intended to provide further detailed descriptions of the present invention. Unless otherwise specified, all technical terms used in the present invention have the same meanings as those generally understood by those skilled in the art to which the present application belongs. The terms used in the present invention are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present invention.

[0028] Following the above technical solution, Figures 1 to 5 As shown, this embodiment provides a floating clamping mechanism and method capable of automatically returning to the center, so that the rotating shaft can not only swing within a certain range while ensuring the rotation accuracy, but also automatically return to the center after the rotating shaft swings.

[0029] The utility model discloses a floating clamping mechanism capable of automatically returning to a center, comprising a piston leveling and returning structure and a floating clamping structure, wherein the piston leveling and returning structure comprises a piston cavity 2, a piston push rod 3, a first sealing ring 4, a piston cavity end cover 5, and a cylindrical spring 6; the floating clamping structure comprises an installation shell 1, a thrust self-aligning ball bearing 7, a second sealing ring 8, a bearing nut 9, a self-aligning ball bearing 10, a rotating shaft 11, a dustproof sealing ring 12, a leveling and fastening rod 13, a flat pressure head 14, and a bearing end cover 15.

[0030] Specifically, the piston cavity 2 is provided with an air inlet hole 2-1 and a mounting countersunk hole 2-4; the piston top rod 3 is installed in the inner cavity of the piston cavity 2, and a circular groove is provided on the piston top rod 3. The interior of the piston cavity 2 is divided into an upper cavity 2-2 and a lower cavity 2-3 by installing a first sealing ring 4; a cylindrical spring 6 is sleeved on the connecting rod of the piston top rod 3, and a piston cavity end cover 5 is installed in the piston cavity 2, and the bottom of the cylindrical spring 6 contacts the bottom surface of the inner hole of the piston cavity end cover 5, and the bolt passes through the mounting countersunk hole 2-4 to connect the piston cavity 2 with the mounting shell 1.

[0031] Furthermore, the piston push rod 3 includes a piston push rod conical surface 3-1. When the piston moves downward, the piston push rod conical surface 3-1 cooperates with the tapered hole mating surface 13-1 of the leveling and fastening rod 13, so that the leveling and fastening rod 13 and the piston push rod 3 remain coaxial; the leveling and fastening rod 13 cooperates with the first cylindrical hole mounting surface 11-1 at the top of the rotating shaft 11 through the cylindrical mating surface 13-2 to ensure the coaxiality of the leveling and fastening rod 13 and the rotating shaft 11.

[0032] Furthermore, the rotating shaft 11 is also designed with a first bearing mounting surface 11-2, a thread 11-3, a second bearing mounting surface 11-4 and a dustproof cylindrical surface 11-5. The self-aligning ball bearing 10 is mounted on the second bearing mounting surface 11-4, the bearing nut 9 is mounted on the rotating shaft 11 through the thread 11-3, and the thrust self-aligning ball bearing 7 is mounted on the first bearing mounting surface 11-2. By designing a suitable thickness of the bearing nut 9, it is ensured that the rotating sphere centers of the thrust self-aligning ball bearing 7 and the self-aligning ball bearing 10 coincide, so that the rotating shaft 11 can swing around the sphere centers of the two.

[0033] Furthermore, the self-aligning ball bearing 10 is installed in the bearing end cover 15, the mounting housing 1 is installed in the bearing end cover 15, a threaded mounting hole 15-1 is opened on the bearing end cover 15, and the mounting housing 1 and the bearing end cover 15 are connected together by screws.

[0034] Furthermore, the mounting housing 1 is designed with a lubrication oil filling port 1-1 and a lubrication channel 1-2. The lubrication oil filling port 1-1 and the lubrication channel 1-2 are connected. When grease is introduced from the lubrication oil filling port 1-1, the grease enters the interior of the mounting housing 1 and the bearing end cover 15 through the lubrication channel 1-2 to lubricate the thrust self-aligning ball bearing 7 and the self-aligning ball bearing 10.

[0035] Furthermore, a second sealing ring 8 is installed on the mounting shell 1 to prevent grease from leaking from the mating surface between the mounting shell 1 and the bearing end cover 15; a dust ring groove 15-2 is opened on the bearing end cover 15 to install a dust seal ring 12, which can prevent external dust from entering on the one hand, and prevent grease from leaking from the dust cylindrical surface 11-5 of the rotating shaft 11 on the other hand.

[0036] The working process of the utility model is as follows:

[0037] First, when the clamping cylinder drives the floating clamping mechanism to press down through the clamping arm, after the bottom surface of the flat pressure head 14 contacts the workpiece, the piston tilts, causing the clamping arm and the floating clamping mechanism to warp. Since the rotating shaft 11 can drive the flat pressure head 14 to swing around the rotating spherical center of the thrust self-aligning ball bearing 7 and the self-aligning ball bearing 10, it has a certain floatability, which can ensure that the bottom surface of the flat pressure head 14 always keeps a close fit with the workpiece.

[0038] When the clamping cylinder drives the floating clamping mechanism to release the workpiece through the clamping arm, the rotating shaft 11 is tilted, and its rotation axis is not perpendicular to the upper end surface of the mounting shell 1. At this time, compressed air with a certain pressure and flow rate is introduced through the air inlet 2-1, and the compressed air enters the upper cavity 2-2, pushing the piston push rod 3 to move downward. The piston push rod conical surface 3-1 of the piston push rod 3 contacts with the tapered hole matching surface 13-1, forcing the leveling and fastening rod 13 to drive the rotating shaft 11 and the piston push rod 3 to resume coaxiality, thereby ensuring that the rotation axis of the rotating shaft 11 is restored to be perpendicular to the upper end surface of the mounting shell 1.

[0039] Furthermore, the compressed air in the upper cavity 2-2 is removed from the air inlet 2-1, and the piston push rod 3 moves upward under the action of the cylindrical spring 6. The piston push rod conical surface 3-1 is no longer in contact with the tapered hole mating surface 13-1, and the rotating shaft 11 can swing around the rotating spherical center of the thrust self-aligning ball bearing 7 and the self-aligning ball bearing 10, and the floating property is restored again, waiting for the next action of the clamping cylinder.

[0040] It is known from common technical knowledge that the present invention can be implemented by other embodiments that do not deviate from its spirit or essential features. Therefore, the embodiments disclosed above are only illustrative in all respects and are not exclusive. All changes within the scope of the present invention or within the scope equivalent to the present invention are included in the present invention.

Claims

1. A floating clamping mechanism capable of automatically returning to its original position, characterized in that: A piston leveling and returning structure consisting of a piston cavity (2), a piston push rod (3), a first sealing ring (4), a piston cavity end cover (5), and a cylindrical spring (6); and a floating pressing structure consisting of a mounting housing (1), a thrust self-aligning ball bearing (7), a second sealing ring (8), a bearing nut (9), a self-aligning ball bearing (10), a rotating shaft (11), a dustproof sealing ring (12), a leveling and fastening rod (13), a flat pressure head (14), and a bearing end cover (15); the piston leveling and returning structure is connected to the floating pressing structure by screws.

2. The floating clamping mechanism capable of automatically returning to its original position according to claim 1, characterized in that: The piston cavity (2) is designed with an air inlet hole (2-1), an upper cavity (2-2), a lower cavity (2-3), and a mounting countersunk hole (2-4); the air inlet hole (2-1) is connected to the upper cavity (2-2); a first sealing ring (4) is installed on the piston top rod (3), dividing the interior of the piston cavity (2) into an upper cavity (2-2) and a lower cavity (2-3); the cylindrical spring (6) is sleeved on the piston top rod (3) and installed in the piston cavity end cover (5); the piston cavity end cover (5) is nested in the piston cavity (2) and connected to the mounting housing (1) by screws through the mounting countersunk hole (2-4).

3. The floating clamping mechanism capable of automatically returning to its original position according to claim 1, characterized in that: The thrust self-aligning ball bearing (7) and the self-aligning ball bearing (10) are installed on the same rotating shaft (11). By properly designing the thickness of the bearing nut (9), the centers of the thrust self-aligning ball bearing (7) and the self-aligning ball bearing (10) are located at the same position, and the rotating shaft (11) can swing around the centers of the thrust self-aligning ball bearing (7) and the self-aligning ball bearing (10); the bearing nut (9) cooperates with the thread (11-3) on the rotating shaft (11).

4. The floating clamping mechanism capable of automatically returning to its original position according to claim 1, characterized in that: The cylindrical mating surface (13-2) of the leveling and tightening rod (13) is tightly matched with the first cylindrical hole mounting surface (11-1) of the rotating shaft (11), thereby driving the rotating shaft (11) and the piston push rod (3) to be coaxial; the second cylindrical hole mounting surface (11-6) of the rotating shaft (11) is tightly matched with the flat pressure head (14), and is installed and fixed by the connecting thread (13-3) of the leveling and tightening rod (13), so that the bottom surface of the flat pressure head (14) is perpendicular to the axis of the piston push rod (3).

5. The floating clamping mechanism capable of automatically returning to its original position according to claim 1, characterized in that: The installation housing (1) is provided with a lubricating oil injection port (1-1) and a lubricating channel (1-2); the lubricating oil injection port (1-1) and the lubricating channel (1-2) are connected; when lubricating grease is introduced from the lubricating oil injection port (1-1), the lubricating grease enters the interior of the installation housing (1) and the bearing end cover (15) through the lubricating channel (1-2) to lubricate the thrust self-aligning ball bearing (7) and the self-aligning ball bearing (10).

6. The floating clamping mechanism capable of automatically returning to its original position according to claim 1, characterized in that: The mounting housing (1) is provided with an annular groove for mounting a second sealing ring (8), and the second sealing ring (8) is used to prevent grease leakage; the bearing end cover (15) is provided with a threaded mounting hole (15-1) and a dustproof ring groove (15-2), and is connected to the mounting housing (1) through the threaded mounting hole (15-1) by screws, and the dustproof ring groove (15-2) is used to mount a dustproof sealing ring (12), and the dustproof sealing ring (12) can prevent external dust from entering on the one hand, and can prevent grease from leaking from the dustproof cylindrical surface (11-5) of the rotating shaft (11) on the other hand.

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