A mechanism capable of performing circumferential rotation and axial movement simultaneously

Abstract

The present invention provides a mechanism capable of performing circumferential rotation and axial movement at the same time, and belongs to the field of mechanical technology. It solves the problem that the existing mechanism capable of performing simultaneous rotation and axial movement has a large axial dimension, is inconvenient to install, and has a poor sealing effect. The mechanism comprises an outer rotating shaft and an inner rotating shaft which is inserted into a center hole through a key fit, one end of the inner rotating shaft is provided with a blind hole, a piston is slidably connected in the blind hole, the outer end of the piston rod is connected with a hydraulic rotary joint, the hydraulic rotary joint comprises an outer cylinder body and a core shaft which is rotatably connected in the outer cylinder body and fixedly connected to the piston rod, one end of the core shaft has a coaxially arranged sealing disk, the outer end of the piston rod has an annular convex edge, the sealing disk is coaxially fixedly connected to the end face of one end of the outer rotating shaft and closes the center hole, the annular convex edge is coaxially arranged with the sealing disk, and the end face of the annular convex edge is fitted and fixedly connected to the end face of the sealing disk. The overall length of the mechanism is shorter, the installation adaptability is better, and it is not easy to wear and leak oil, and the sealing effect is better.

Description

Technical Field

[0001] The invention belongs to the field of mechanical technology and relates to a mechanism capable of performing circumferential rotation and axial movement simultaneously. Background Art

[0002] In the field of mechanics, sometimes we need some mechanisms to achieve both circumferential rotation and axial movement. Since two driving sources are usually required to be applied to the same shaft at the same time to achieve the above two actions, the structure is relatively complex and the design is difficult.

[0003] For example, a sizing machine deceleration and telescopic mechanism with a rotary joint disclosed in a Chinese patent application (application number: 201520870169.2) realizes the above-mentioned action. The sizing machine deceleration and telescopic mechanism includes a driving shaft with a transmission gear, a spline shaft extending into the driving shaft, a coupling connected to the output end of the spline shaft, and a piston rod for driving the spline shaft to telescope in the main shaft. The piston rod is connected to the spline shaft through a rotary joint and a slender shaft. In this way, the driving shaft is driven to rotate by an external power source in cooperation with the transmission gear on the main shaft, and the driving shaft drives the spline shaft to rotate synchronously through the spline cooperation, and the piston rod can drive the spline shaft to move axially, so that the spline shaft can simultaneously achieve circumferential rotation and axial movement. However, since the piston cylinder of this structure needs to be set at the outer end of the driving shaft and the spline shaft, and the piston cylinder itself is long, the sizing machine deceleration and telescopic mechanism occupies a large space, which is easy to cause interference in some occasions where the installation size is relatively tight, which brings great difficulty to both design and installation.

[0004] The Chinese patent application (application number: 201820486320.6) discloses a rotary telescopic combined oil cylinder, which adopts a structure of connecting a telescopic cylinder and a rotary cylinder in series, a blind hole is set in the telescopic piston rod, and the peripheral part of the blind hole wall is connected to the rotary transmission rod of the rotary cylinder through a spline transmission, so that the rotary transmission rod can drive the telescopic piston rod to rotate, and the telescopic piston rod can move along its own axial direction relative to the rotary transmission rod. Although this structure is more compact than the sizing machine deceleration telescopic mechanism, however, since the rotary cylinder can only provide limited rotational movement within the stroke of the rotary piston, it cannot provide continuous unidirectional rotation like a motor, and its scope of application is small. In addition, in this structure, the telescopic piston rod must rotate relative to the telescopic cylinder body and move axially relative to the telescopic cylinder body, resulting in a large relative sliding amount between the telescopic piston rod and the telescopic cylinder body, that is, a large amount of friction between the two, a greater sealing difficulty, and a high risk of oil leakage. Summary of the invention

[0005] The purpose of the present invention is to address the above-mentioned problems in the prior art and to propose a mechanism that can simultaneously perform circumferential rotation and axial movement. The technical problem to be solved by the present invention is: how to make the structure of the mechanism that can simultaneously perform circumferential rotation and axial movement more compact and have a better sealing effect.

[0006] The object of the present invention can be achieved through the following technical solutions: a mechanism that can simultaneously perform circumferential rotation and axial movement, comprising a rotatable outer shaft having a center hole and an inner shaft inserted into the center hole by key fitting, characterized in that a blind hole is opened axially at one end of the inner shaft, a piston is axially slidably connected in the blind hole to separate the blind hole into a first oil chamber and a second oil chamber, a piston rod is connected to the piston, a first flow channel communicating with the first oil chamber and a second flow channel communicating with the second oil chamber are provided on the piston rod, and the piston rod is away from the piston rod. One end of the plug is connected to a hydraulic rotary joint, which has a third flow channel connected to the first flow channel and a fourth flow channel connected to the second flow channel. The hydraulic rotary joint includes an outer cylinder and a core shaft rotatably connected to the outer cylinder and fixedly connected to the piston rod. One end of the core shaft has a coaxially arranged sealing disk, and the outer end of the piston rod has an annular flange. The sealing disk is coaxially fixedly connected to the end face of one end of the outer rotating shaft and closes the center hole. The annular flange is coaxially arranged with the sealing disk, and the end face of the annular flange is fitted and fixedly connected to the end face of the sealing disk.

[0007] The outer rotating shaft of the present invention can be connected to the driving member for rotation, and the inner rotating shaft is connected to the outer rotating shaft by a key, so that the inner rotating shaft can rotate synchronously with the outer rotating shaft and move axially relative to the outer rotating shaft. A blind hole is provided on the inner rotating shaft and cooperates with the piston and the piston rod to form a hydraulic cylinder. The first flow channel and the second flow channel for driving the piston to move are provided on the piston rod, which is connected to the hydraulic rotary joint arranged outside the outer rotating shaft through the piston rod, and the first flow channel and the second flow channel are connected through the hydraulic rotary joint. In this way, it is only necessary to fix the outer cylinder of the hydraulic rotary joint, that is, to supply oil to the hydraulic cylinder through the hydraulic rotary joint and drive the inner rotating shaft to move axially relative to the outer rotating shaft, thereby cooperating with the torque of the outer rotating shaft to realize the rotation and axial movement of the inner rotating shaft. Moreover, since the hydraulic cylinder structure is basically located inside the outer rotating shaft, the overall axial length of the present invention can be designed to be shorter, which is convenient for overall application in various locations with tight assembly space.

[0008] At the same time, the mandrel of the hydraulic rotary joint is fixedly connected to the piston rod and the end face of the outer shaft, so that the mandrel, the piston rod and the outer shaft form a whole, so that the mandrel, the piston rod and the outer shaft can keep rotating synchronously, thereby avoiding the rotation speed difference between the piston and the piston rod and the outer shaft, thereby avoiding the friction caused by the rotation speed difference between the piston and the piston rod, making the sealing effect of the hydraulic cylinder structure better and reducing the leakage of oil. Since the piston rod and the mandrel are fixedly connected with the sealing disk through the annular convex edge, the contact area between the mandrel and the piston rod is larger, the connection is more stable, and the coaxiality is higher, so that the movement and matching accuracy between the outer shaft and the inner shaft, between the piston and the inner shaft, and between the piston rod and the sealing cover is higher, the wear caused by relative sliding is less, and the sealing effect is better. In addition, the sealing disk of the mandrel closes the hydraulic cylinder structure in the center hole of the outer shaft, and also plays a role of protection and dust prevention.

[0009] In the above-mentioned mechanism that can perform circumferential rotation and axial movement at the same time, the outer cylinder body is cylindrical, and the inner wall of the outer cylinder body is provided with an annular first oil groove and a second oil groove along the circumferential direction, and the first oil groove and the second oil groove are distributed at intervals along the axial direction of the outer cylinder body, and the outer wall of the outer cylinder body is provided with a first oil hole connected with the first oil groove and a second oil hole connected with the second oil groove, and the core shaft is provided with a first oil channel and a second oil channel, one end of the first oil channel and the second oil channel are both located on the side wall of the core shaft and are respectively connected with the first oil groove and the second oil groove, and the other end of the first oil channel and the second oil channel are both located on the end face of one end of the core shaft, the first oil hole, the first oil groove and the first oil channel together form a third flow channel, and the second oil hole, the second oil groove and the second oil channel together form a fourth flow channel. The outer cylinder of the hydraulic rotary joint is connected to the external oil circuit system, and the outer cylinder remains stationary when the outer shaft rotates. The core shaft is connected to the piston rod and rotates synchronously with the piston rod, and the oil circuit between the core shaft and the outer cylinder is always kept connected. The external oil circuit controls the axial extension and contraction of the inner shaft through the hydraulic rotary joint.

[0010] In the above-mentioned mechanism that can perform axial rotation and axial movement at the same time, the annular ridge is in contact with the sealing disk and is fixedly connected by bolts. Two annular grooves surrounding the first oil channel and the second oil channel respectively are formed on the end surface of the sealing disk. O-rings are embedded in the annular grooves to ensure the sealing of the oil circuit.

[0011] In the above-mentioned mechanism capable of simultaneously performing axial rotation and axial movement, three sealing rings are arranged between the inner wall of the outer cylinder and the outer wall of the core shaft, and the sealing rings are arranged at intervals along the length direction of the core shaft, and the first oil groove and the second oil groove are respectively located between two adjacent sealing rings. In this way, the sealing effect of the first oil groove and the second oil groove can be ensured, and the accuracy of the axial movement of the inner rotating shaft can be ensured.

[0012] In the above-mentioned mechanism capable of simultaneously performing axial rotation and axial movement, the inner wall of the center hole is fixedly provided with guide blocks at intervals along the circumferential direction, and the outer wall of the inner shaft is provided with a plurality of guide grooves corresponding to and slidingly matched with the guide blocks, and the guide grooves extend along the axial direction of the inner shaft. The guide blocks and the guide grooves form the above-mentioned key fit, so that the outer shaft can drive the inner shaft to rotate, and the inner shaft can move axially relative to the outer shaft.

[0013] In the above-mentioned mechanism capable of simultaneously performing axial rotation and axial movement, a transmission member is sleeved and fixed on the outer shaft, and the transmission member is a transmission gear or a pulley, and the guide block is located on the inner wall of the outer shaft where the transmission member is arranged. The transmission member and the guide block are arranged at substantially the same axial position on the outer shaft, so that the torque of the transmission member driving the outer shaft to rotate and the torque of the guide block driving the inner shaft are substantially at the same axial position, avoiding the generation of eccentric load between the outer shaft and the inner shaft, and the coaxiality between the outer shaft and the inner shaft is higher, and the relative sliding is smoother.

[0014] In the above-mentioned mechanism that can perform axial rotation and axial movement at the same time, the end of the inner shaft with a blind hole is located in the center hole and has a distance from the sealing disk. The outer diameter of the sealing disk is greater than or equal to the outer diameter of the outer shaft, and the outer diameter of the annular flange is smaller than the aperture of the center hole.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] 1. The present invention has a compact structure. The outer rotating shaft and the inner rotating shaft are connected by a key, and a hydraulic cylinder structure is arranged between the inner rotating shaft and the outer rotating shaft. The hydraulic cylinder structure is located inside the outer rotating shaft, so that the hydraulic cylinder structure can drive the inner rotating shaft to move axially while making the axial length of the structure as short as possible, so that the present structure has a wider applicability.

[0017] 2. The core shaft of the hydraulic rotary joint has a sealing disk, which is fitted and fixedly connected to the end face of the outer shaft and seals the inner shaft and the hydraulic cylinder structure in the center hole. At the same time, the piston rod is also fixedly connected to the sealing disk through an annular convex edge, so that the piston rod, piston, inner shaft, outer shaft and core shaft can keep rotating synchronously, thereby avoiding wear caused by speed difference between the above components and ensuring sealing.

[0018] 3. The structure of this case is ingenious. The first flow channel and the second flow channel are opened on the piston rod, and are connected to the external hydraulic system through a hydraulic rotary joint, so that the piston rod can follow the rotation of the outer shaft and the inner shaft while ensuring the stable control of the axial movement of the inner shaft by the hydraulic system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the present invention;

[0020] Figure 2It is a schematic diagram of the hydraulic cylinder structure;

[0021] Figure 3 It is a schematic diagram of the structure of a hydraulic rotary joint;

[0022] Figure 4 yes Figure 1 Cross-sectional view at AA in the middle.

[0023] In the figure, 1, outer rotating shaft; 11, center hole; 12, transmission member; 13, guide block; 2, inner rotating shaft; 21, blind hole; 21a, first oil chamber; 21b, second oil chamber; 22, guide groove; 31, piston; 32, piston rod; 32a, first flow channel; 32b, second flow channel; 32c, annular ridge; 33, sealing cover; 4, hydraulic rotary joint; 41, outer cylinder; 41a, first oil hole; 41b, second oil hole; 41c, first oil groove; 41d, second oil groove; 42, core shaft; 42a, first oil channel; 42b, second oil channel; 42c, sealing plate; 5, third flow channel; 6, fourth flow channel; 7a, sealing ring; 7b, O-ring. DETAILED DESCRIPTION

[0024] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0025] like Figure 1 , Figure 2 As shown, a mechanism capable of performing circumferential rotation and axial movement at the same time comprises an outer rotating shaft 1 and an inner rotating shaft 2. The outer rotating shaft 1 is a cylindrical structure with a center hole 11 arranged along the axis line. The inner rotating shaft 2 is inserted into the center hole 11 by key fitting. A blind hole 21 is opened in the axial direction at one end of the inner rotating shaft 2. A piston 31 and a piston rod 32 connected to the piston 31 are arranged in the blind hole 21. The piston 31 separates the blind hole 21 into a first oil chamber 21a and a second oil chamber 21b. The end of the piston rod 32 away from the piston 31 extends out of the inner hole 21. The rotating shaft 2 is connected to the hydraulic rotary joint 4. At the same time, the piston rod 32 is provided with a first flow channel 32a connected to the first oil chamber 21a and a second flow channel 32b connected to the second oil chamber 21b. The first flow channel 32a and the second flow channel 32b are respectively connected to the third flow channel 5 and the fourth flow channel 6 on the hydraulic rotary joint 4, and the third flow channel 5 and the fourth flow channel 6 on the hydraulic rotary joint 4 can be connected to the external hydraulic system, so that a hydraulic cylinder system is formed between the inner rotating shaft 2, the piston 31 and the piston rod 32. When in use, the outer rotating shaft 1 can be connected to the driving source and can rotate, and the hydraulic system can transport oil to the first flow channel 32a or the second flow channel 32b through the hydraulic rotary joint 4, so that the outer rotating shaft 1 can drive the inner rotating shaft 2 to rotate synchronously and the inner rotating shaft 2 can move axially relative to the outer rotating shaft 1.

[0026] Specifically, Figures 1 to 3As shown, the outer shaft 1 is sleeved and fixed with a bearing and a transmission member 12, and the transmission member 12 is a transmission gear or a pulley, so that the outer shaft 1 can be driven to rotate with a driving member such as a driving motor through the transmission gear or the pulley. The hydraulic rotary joint 4 includes an outer cylinder 41 and a core shaft 42. The outer cylinder 41 is cylindrical, and the core shaft 42 is rotatably connected to the outer cylinder 41 and one end of the core shaft 42 extends outward. The inner wall of the outer cylinder 41 is provided with a first annular oil groove 41c and a second oil groove 41d in the circumferential direction. The first oil groove 41c and the second oil groove 41d are spaced apart along the axial direction of the outer cylinder 41. The outer wall of the outer cylinder 41 is provided with a first oil hole 41a connected to the first oil groove 41c and a second oil hole 41b connected to the second oil groove 41d, and the core shaft 42 is provided with a first oil passage 42a and a second oil passage 42b. One end of the first oil passage 42a and the second oil passage 42b are both located on the side wall of the core shaft 42 and are connected to the first oil groove 41c and the second oil groove 41d respectively. The other ends of the first oil passage 42a and the second oil passage 42b are both located on the end surface of the core shaft 42 extending out of the outer cylinder 41. The first oil hole 41a, the first oil groove 41c and the first oil passage 42a together form the third flow passage 5, and the second oil hole 41b, the second oil groove 41d and the second oil passage 42b together form the fourth flow passage 6, and ensure that the third flow passage 5 and the fourth flow passage 6 are unobstructed when the core shaft 42 rotates relative to the outer cylinder 41. At the same time, the end of the core shaft 42 extending out of the outer cylinder 41 is fixedly connected to the piston rod 32, and the first oil passage 42a is connected to the first flow passage 32a, and the second oil passage 42b is connected to the second flow passage 32b, so as to realize the control of the axial movement of the inner shaft 2.

[0027] like Figures 1 to 3As shown, a sealing cover 33 is coaxially arranged in the blind hole 21 of the inner shaft 2. The sealing cover 33 is located at the outer end of the blind hole 21 and is used to seal the piston 31 in the blind hole 21. One end of the piston rod 32 passes through the sealing cover 33 and extends out of the inner shaft 2. The end of the inner shaft 2 with the blind hole 21 is located in the center hole 11, and the end face of the inner shaft 2 with the blind hole 21 is spaced a certain distance from the end face of the adjacent outer shaft 1. The end of the core shaft 42 extending out of the outer cylinder 41 has a sealing disk 42c. The outer diameter of the sealing disk 42c is greater than or equal to the outer diameter of the outer shaft 1. The sealing disk 42c is fixed to the end face of the outer shaft 1 by bolts, so that The sealing disk 42c closes the side opening of the center hole 11, and the end of the piston rod 32 extending out of one end of the inner shaft 2 has an annular convex edge 32c, the outer diameter of the annular convex edge 32c is smaller than the aperture of the center hole 11, and the annular convex edge 32c is coaxially arranged with the sealing disk 42c, and the end surface of the annular convex edge 32c is in contact with the end surface of the sealing disk 42c and is fixedly connected by bolts, so that the piston rod 32, the outer shaft 1 and the core shaft 42 are fixedly connected to form a whole, ensuring the synchronization of the rotation of the piston rod 32, the outer shaft 1, the inner shaft 2 and the core shaft 42, so that the piston 31 and the piston rod 32 reduce the friction in the circumferential direction, reduce wear and ensure sealing. In the actual production process, since the hydraulic rotary joint 4 is usually produced separately by a special manufacturer, that is, the hydraulic rotary joint 4 and the outer shaft 1, the inner shaft 2 and the hydraulic cylinder structure and other components are produced by different manufacturers, the use of this structure also facilitates the matching and assembly between the hydraulic rotary joint 4 and the above components.

[0028] Furthermore, two annular grooves are formed on the end surface of the sealing disk 42c, surrounding the first oil passage 42a and the second oil passage 42b respectively. O-rings 7b are embedded in the annular grooves to prevent oil leakage.

[0029] Furthermore, three sealing rings 7a are arranged between the inner wall of the outer cylinder 41 and the outer wall of the core shaft 42. The sealing rings 7a are arranged at intervals along the length direction of the core shaft 42. The first oil groove 41c and the second oil groove 41d are respectively located between two adjacent sealing rings 7a.

[0030] like Figure 4 As shown, the inner wall of the center hole 11 is fixed with guide blocks 13 at intervals along the circumferential direction, and the outer wall of the inner shaft 2 is provided with a plurality of guide grooves 22 which correspond to the guide holes one by one and slide together, and the guide grooves 22 extend along the axial direction of the inner shaft 2, and the guide blocks 13 are located on the inner wall of the outer shaft 1 where the transmission member 12 is provided. In this case, the key fit between the inner shaft 2 and the outer shaft 1 is realized by the guide blocks 13 and the guide grooves 22, which is more convenient for processing.

[0031] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0032] Although the terms such as outer shaft 1, inner shaft 2, piston 31, piston rod 32, hydraulic rotary joint 4 are used more frequently in this article, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional restrictions is contrary to the spirit of the present invention.

Claims

1. A mechanism capable of simultaneously performing circumferential rotation and axial movement, comprising an outer rotating shaft (1) which is rotatable and has a center hole (11) and an inner rotating shaft (2) which is inserted into the center hole (11) by key fitting, characterized in that: A blind hole (21) is axially formed at one end of the inner rotating shaft (2); a piston (31) is axially slidably connected in the blind hole (21) so as to separate the blind hole (21) into a first oil chamber (21a) and a second oil chamber (21b); a piston rod (32) is connected to the piston (31); a first flow channel (32a) communicating with the first oil chamber (21a) and a second flow channel (32b) communicating with the second oil chamber (21b) are provided on the piston rod (32); an end of the piston rod (32) away from the piston (31) is connected to a hydraulic rotary joint (4); the hydraulic rotary joint (4) has a third flow channel (5) communicating with the first flow channel (32a) and a second flow channel (32b) communicating with the second oil chamber (21b) The hydraulic rotary joint (4) comprises an outer cylinder (41) and a core shaft (42) rotatably connected to the outer cylinder (41) and fixedly connected to the piston rod (32); one end of the core shaft (42) has a coaxially arranged sealing disk (42c); the outer end of the piston rod (32) has an annular convex edge (32c); the sealing disk (42c) is coaxially fitted and fixedly connected to the end surface of one end of the outer rotating shaft (1) and closes the central hole (11); the annular convex edge (32c) is coaxially arranged with the sealing disk (42c), and the end surface of the annular convex edge (32c) is fitted and fixedly connected to the end surface of the sealing disk (42c); the outer cylinder (41) is cylindrical The outer cylinder (41) has an inner wall with a first oil groove (41c) and a second oil groove (41d) in an annular shape along the circumferential direction, and the first oil groove (41c) and the second oil groove (41d) are spaced apart along the axial direction of the outer cylinder (41). The outer wall of the outer cylinder (41) has a first oil hole (41a) in communication with the first oil groove (41c) and a second oil hole (41b) in communication with the second oil groove (41d). The core shaft (42) has a first oil passage (42a) and a second oil passage (42b). One end of each of the first oil passage (42a) and the second oil passage (42b) are located on the side wall of the core shaft (42) and are respectively connected to the first oil groove (41c) and the second oil groove (41d). 41d), the other ends of the first oil passage (42a) and the second oil passage (42b) are both located on the end surface of one end of the core shaft (42), the first oil hole (41a), the first oil groove (41c) and the first oil passage (42a) together form a third flow passage (5), and the second oil hole (41b), the second oil groove (41d) and the second oil passage (42b) together form a fourth flow passage (6); the annular convex edge (32c) is in contact with the sealing plate (42c) and is fixedly connected by bolts, and the end surface of the sealing plate (42c) is provided with two annular grooves respectively surrounding the first oil passage (42a) and the second oil passage (42b), and O-rings (7b) are embedded in the annular grooves;Three sealing rings (7a) are arranged between the inner wall of the outer cylinder (41) and the outer wall of the core shaft (42), and the sealing rings (7a) are arranged at intervals along the length direction of the core shaft (42), and the first oil groove (41c) and the second oil groove (41d) are respectively located between two adjacent sealing rings (7a); the inner wall of the center hole (11) is fixedly provided with guide blocks (13) at intervals along the circumferential direction, and the outer wall of the inner rotating shaft (2) is provided with a plurality of guide grooves (22) corresponding to the guide blocks (13) and slidingly matched, and the guide grooves (22) extend along the axial direction of the inner rotating shaft (2). ; 2. The mechanism capable of performing circumferential rotation and axial movement simultaneously according to claim 1, characterized in that: A transmission member (12) is sleeved and fixed on the outer rotating shaft (1), and the transmission member (12) is a transmission gear or a pulley. The guide block (13) is located on the inner wall of the outer rotating shaft (1) where the transmission member (12) is provided.

3. The mechanism capable of performing circumferential rotation and axial movement simultaneously according to claim 1, characterized in that: One end of the inner shaft (2) having a blind hole (21) is located in the center hole (11) and is spaced apart from the sealing disk (42c); the outer diameter of the sealing disk (42c) is greater than or equal to the outer diameter of the outer shaft (1); and the outer diameter of the annular protrusion (32c) is smaller than the diameter of the center hole (11).

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