Double-helix swing hydraulic cylinder adopting fixed cantilever structure

Abstract

The invention relates to the technical field of hydraulic transmission and precision mechanical control, and discloses a double-helix swing hydraulic cylinder adopting a fixed cantilever structure, which comprises a cylinder body, a cantilever screw rod and a hollow screw rod, and the middle section of the cantilever screw rod is arranged in the cylinder body; a hollow screw rod in the cylinder body is arranged on the periphery of the cantilever screw rod in a sleeving manner, and the hollow screw rod divides a channel in the cylinder body into a first cavity and a second cavity which are spaced from each other; the inner wall face of one end of the hollow screw is in threaded fit with the outer wall face of the cantilever screw to form a first-stage thread pair, the outer wall face of the other end of the hollow screw is in threaded fit with the inner wall face of the cylinder body to form a second-stage thread pair, and the first-stage thread pair and the second-stage thread pair are opposite in rotating direction. Oil conveying channels are arranged on the two sides of the cantilever screw correspondingly. The swing mechanism is small in installation space and long in service life, can repeatedly swing and output large torque by rotating the cylinder body under the condition that the requirement for fixing the cantilever is met, and is suitable for high-torque and high-precision scenes such as intelligent variable-configuration aircraft folding wing driving and industrial robot joints.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic transmission and precision machinery control, and more specifically, to a double-helical swing hydraulic cylinder adopting a fixed cantilever structure. Background Art

[0002] With the development of near-space aircraft and intelligent variable configuration aircraft, the demand for deployable and deformable mechanisms that can be repeatedly folded is becoming increasingly urgent. Traditional folding wing drive technologies (such as pyrotechnic screws and motor lead screws) have the following defects: low repeat life, volume and weight limitations, and insufficient dynamic response.

[0003] Therefore, it is necessary to improve and innovate the existing folding wing drive technology to improve its repeat service life, reduce the installation space, and be able to output large torque. Summary of the Invention

[0004] In view of this, the present invention proposes a double-helical swing hydraulic cylinder adopting a fixed cantilever structure with high power density and direct torque output characteristics, which can output large torque by rotating the cylinder body while satisfying the fixed cantilever.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A double-helical swing hydraulic cylinder adopting a fixed cantilever structure includes a cylinder body, a cantilever screw, and a hollow screw. A channel extending along the axial direction of the cylinder body is defined in the cylinder body. The middle section of the cantilever screw is partially disposed in the channel and extends along the axial direction of the channel. The hollow screw, which is also located in the channel, is sleeved on the outer periphery of the cantilever screw, and the hollow screw divides the channel into mutually spaced first and second chambers. The inner wall surface of one end of the hollow screw is in threaded engagement with the outer wall surface of the cantilever screw to form a first-stage thread pair, and the outer wall surface of the other end of the hollow screw is in threaded engagement with the inner wall surface of the cylinder body to form a second-stage thread pair. The first-stage thread pair and the second-stage thread pair have opposite helix directions. First and second oil inlet holes are respectively opened at the front and rear ends of the cantilever screw. First and second oil outlet holes are opened on the rod body of the cantilever screw located in the first and second chambers respectively. The first oil inlet hole communicates with the first chamber through a first oil transmission passage axially opened in the cantilever screw and the first oil outlet hole. The second oil inlet hole communicates with the second chamber through a second oil transmission passage axially opened in the cantilever screw and the second oil outlet hole. A first end cover for closing the first chamber is sleeved on the front side of the cantilever screw, and a second end cover for closing the second chamber is sleeved on the rear side of the cantilever screw.

[0007] Preferably, a first shaft groove is formed in the outer periphery of the front side of the cantilever screw, and a second shaft groove is formed in the outer periphery of the rear side. A first shaft circlip is installed in the first shaft groove, and a second shaft circlip is installed in the second shaft groove; a first clamping groove is formed in the inner wall of the front side of the cylinder block, and a second clamping groove is formed in the inner wall of the rear side. A first elastic circlip is installed in the first clamping groove, and a second elastic circlip is installed in the second clamping groove; the first shaft circlip and the first elastic circlip jointly act to axially position the first end cover, and the second shaft circlip and the second elastic circlip jointly act to axially position the second end cover; a first thrust bearing is installed between the first end cover and the first shaft circlip, and a first radial bearing is installed between the first end cover and the cantilever screw; a second thrust bearing is installed between the second end cover and the second shaft circlip, and a second radial bearing is installed between the second end cover and the cantilever screw; the two thrust bearings are used to bear the axial load of the cantilever screw, and the two radial bearings are used to bear the radial load of the cantilever screw.

[0008] Preferably, first sealing rings are correspondingly installed between the two end covers and the corresponding cantilever screw and between the two end covers and the cylinder block.

[0009] Preferably, second sealing rings are correspondingly installed between the hollow screw and the cantilever screw and between the hollow screw and the cylinder block.

[0010] Preferably, key grooves for connecting with the corresponding mounting seats on the corresponding sides are formed on the outer peripheral surfaces of the front and rear ends of the cantilever screw.

[0011] Preferably, a plurality of the first oil outlet holes and a plurality of the second oil outlet holes are circumferentially and evenly formed at corresponding positions on the middle rod body of the cantilever screw.

[0012] Compared with the prior art, the double-screw swing hydraulic cylinder with a fixed cantilever structure of the present invention has the following advantages:

[0013] 1. The device of the present invention adopts a structural design with a fixed cantilever screw, with the rotation of the cylinder block as the output, and is more compact in structure and has a small installation space.

[0014] 2. As a hydrostatic component, the device of the present invention uses hydraulic oil as the working medium and also lubricates each transmission component, which can effectively improve the service life of the transmission device.

[0015] 3. The device of the present invention converts hydraulic energy into mechanical energy, and the cylinder block drives the load to make reciprocating swings. Compared with traditional swing actuators, it has the characteristics of being able to swing repeatedly and having a large output torque.

[0016] 4. The device of the present invention is used as an actuating element in a hydraulic system, and can support hydraulic-electric dual-mode drive (realized through a switching valve group), be compatible with the diverse power requirements of industrial robots, warehousing logistics, and special equipment (such as the pitching mechanism of shipborne radars), and has multi-scenario adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0018] Figure 1 A perspective view of a double-helix oscillating hydraulic cylinder with a fixed cantilever structure according to the present invention.

[0019] Figure 2 A front view of a double-helix oscillating hydraulic cylinder with a fixed cantilever structure according to the present invention.

[0020] Figure 3 A top view of a double-helix oscillating hydraulic cylinder with a fixed cantilever structure according to the present invention.

[0021] Figure 4 A left view of a double-helix oscillating hydraulic cylinder with a fixed cantilever structure according to the present invention.

[0022] Figure 5 A sectional view of a double-helix oscillating hydraulic cylinder with a fixed cantilever structure according to the present invention.

[0023] Figure 6 A schematic structural view of the cylinder block in the present invention.

[0024] Figure 7 A schematic structural view of the cantilever screw in the present invention.

[0025] Figure 8 A schematic structural view of the hollow screw in the present invention.

[0026] Figure 9 A working principle diagram of the present invention.

[0027] In the figure: 1 - cylinder block, 2 - cantilever screw, 3 - hollow screw, 4 - first chamber, 5 - second chamber, 6 - first oil inlet hole, 7 - second oil inlet hole, 8 - first oil outlet hole, 9 - second oil outlet hole, 10 - first oil delivery passage, 11 - second oil delivery passage, 12 - first end cover, 13 - second end cover, 14 - first shaft circlip, 15 - second shaft circlip, 16 - first elastic circlip, 17 - second elastic circlip, 18 - first thrust bearing, 19 - first radial bearing, 20 - second thrust bearing, 21 - second radial bearing, 22 - first sealing ring, 23 - second sealing ring, 24 - keyway. Detailed implementation manners

[0028] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, and should not be construed as a limitation to the present invention.

[0029] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0030] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0031] Embodiment:

[0032] A double - helix swing hydraulic cylinder with a fixed - cantilever structure, having high power density and direct torque output characteristics, can output large torque by rotating the cylinder block while satisfying the fixed - cantilever condition, and is applicable to high - torque and high - precision scenarios such as the folding - wing drive of intelligent variable - configuration aircraft and the joints of industrial robots.

[0033] The following will be combined with Figures 1-9 to make a detailed description of this embodiment:

[0034] A double - helix swing hydraulic cylinder adopting a fixed - cantilever structure mainly includes a cylinder block 1, a cantilever screw 2, and a hollow screw 3.

[0035] Among them, a channel extending along the axial direction of the cylinder block 1 is defined inside the cylinder block 1, and the middle section of the cantilever screw 2 is arranged inside the channel and extends along the axial direction of the channel; the hollow screw 3 also located inside the channel is sleeved on the outer periphery of the cantilever screw 2, and the hollow screw 3 divides the channel into mutually spaced first chamber 4 and second chamber 5; the inner wall surface of one end of the hollow screw 3 is in threaded fit with the outer wall surface of the cantilever screw 2 to form a first-level thread pair (as indicated by a at Figure 9 the place shown), the outer wall surface of the other end of the hollow screw 3 is in threaded fit with the inner wall surface of the cylinder block 1 to form a second-level thread pair (as indicated by b at Figure 9 the place shown), and the helix directions of the first-level thread pair and the second-level thread pair are opposite.

[0036] The front and rear ends of the cantilever screw 2 are respectively provided with a first oil inlet hole 6 and a second oil inlet hole 7, a first oil outlet hole 8 is opened on the rod body of the cantilever screw 2 located in the first chamber 4, a second oil outlet hole 9 is opened on the rod body of the cantilever screw 2 located in the second chamber 5, the first oil inlet hole 6 is communicated with the first chamber 4 through a first oil transmission passage 10 opened along the axial direction inside the cantilever screw and through the first oil outlet hole 8, and the second oil inlet hole 7 is communicated with the second chamber 5 through a second oil transmission passage 11 opened along the axial direction inside the cantilever screw and through the second oil outlet hole 9.

[0037] A first end cover 12 for closing the first chamber 4 is sleeved on the front side of the cantilever screw 2, and a second end cover 13 for closing the second chamber 5 is sleeved on the rear side of the cantilever screw 2.

[0038] When this device is in use, first fix both sides of the cantilever screw 2, and then utilize the functions of the first-level thread pair between the hollow screw 3 and the cantilever screw 2 and the second-level thread pair between the hollow screw 3 and the cylinder block 1. When high-pressure oil enters the left first chamber 4 through the first oil inlet hole 6, the first oil transmission passage 10, and the first oil outlet hole 8, the high-pressure oil will push the hollow screw 3 to move to the right while the hollow screw 3 makes a rotational movement, and due to the function of the second-level thread pair, the cylinder block 1 generates a rotational movement in the opposite direction to the hollow screw 3, thereby realizing high torque output; correspondingly, when high-pressure oil enters the right second chamber 5 through the second oil inlet hole 7, the second oil transmission passage 11, and the second oil outlet hole 9, the high-pressure oil will push the hollow screw 3 to move to the left while the hollow screw 3 makes a rotational movement, and the high-pressure oil in the first chamber 4 flows back along the original path, and due to the function of the second-level thread pair, the cylinder block 1 still generates a rotational movement in the opposite direction to the hollow screw 3, thereby realizing high torque output.

[0039] By injecting oil into the oil inlet holes on different sides, the device can control the rotation direction of the cylinder block, enabling the cylinder block to rotate clockwise and counterclockwise. That is, the device converts hydraulic energy into mechanical energy, and the cylinder block drives the load to reciprocate. Compared with traditional swing actuators, it has the characteristics of being able to swing repeatedly and having a large output torque.

[0040] Moreover, the device adopts a structural design of a fixed cantilever screw, with the rotation of the cylinder block as the output, making the whole device more compact in structure. And since only the two ends of the cantilever screw need to be fixed, the installation space is small. This optimization is particularly crucial in fields such as the folding wing drive of intelligent variable configuration aircraft and the joints of industrial robots where space is limited or lightweight design is required.

[0041] Meanwhile, as a hydrostatic component, the device uses hydraulic oil as the working medium, which also lubricates the transmission components, effectively improving the service life of the transmission device.

[0042] In a further specific embodiment, a first axial groove is provided on the outer periphery of the front side of the cantilever screw 2, and a second axial groove is provided on the outer periphery of the rear side. A first axial snap ring 14 is installed in the first axial groove, and a second axial snap ring 15 is installed in the second axial groove; a first clamping groove is provided on the inner wall of the front side of the cylinder block 1, and a second clamping groove is provided on the inner wall of the rear side. A first elastic clamping ring 16 is installed in the first clamping groove, and a second elastic clamping ring 17 is installed in the second clamping groove; the first axial snap ring 14 and the first elastic clamping ring 16 jointly act to axially position the first end cover 12, and the second axial snap ring 15 and the second elastic clamping ring 17 jointly act to axially position the second end cover 13. A first thrust bearing 18 is installed between the first end cover 12 and the first axial snap ring 14, and a first radial bearing 19 is installed between the first end cover 12 and the cantilever screw 2; a second thrust bearing 20 is installed between the second end cover 13 and the second axial snap ring 15, and a second radial bearing 21 is installed between the second end cover 13 and the cantilever screw 2; the two thrust bearings on the left and right are used to bear the axial load of the cantilever screw 2, and the two radial bearings on the left and right are used to bear the radial load of the cantilever screw 2. The two end covers in the device limit the axial movement of their respective thrust bearings, ensuring that the thrust bearings remain stable when bearing the axial load and preventing them from moving on the shaft.

[0043] Meanwhile, first sealing rings 22 are correspondingly installed between the two end covers and the corresponding cantilever screw 2 and between the end covers and the cylinder block 1. Second sealing rings 23 are correspondingly installed between the hollow screw 3 and the cantilever screw 2 and between the hollow screw 3 and the cylinder block 1. These sealing rings play a sealing role at their respective corresponding positions.

[0044] In a further specific embodiment, for the convenience of installation, key grooves 24 for connecting with the corresponding mounting seats are provided on the outer peripheral surfaces of the front and rear ends of the cantilever screw 2.

[0045] Meanwhile, to ensure the driving effect of the high-pressure oil, a plurality of first oil outlet holes 8 and a plurality of second oil outlet holes 9 are respectively and circumferentially and evenly formed at corresponding positions of the rod body in the cantilever screw rod 2.

[0046] The following provides a set of specific data of the actual structures of the device of the present invention:

[0047] A double-screw swing hydraulic cylinder adopting a fixed cantilever structure has a working pressure of 35 Mpa, a maximum cylinder diameter of 65 mm, a cylinder inner diameter of 50 mm, a cylinder wall thickness of 7.5 mm, a total cylinder length of 300 mm, an outer thread major diameter of 38 mm, a pitch diameter of 36 mm, a helix angle of 50°, and a lead of 136.8 mm for the first-stage thread pair; an outer thread major diameter of 58 mm, a pitch diameter of 56 mm, a helix angle of 50°, and a lead of 215.3 mm for the second-stage thread pair; an output torque of 682 Nm, and a deployable angle of 105°.

[0048] The device of the present invention is used as an actuator in a hydraulic system, can support hydraulic-electric dual-mode drive (realized by switching valve groups), is compatible with the diverse power requirements of industrial robots, warehousing logistics, and special equipment (such as the pitching mechanism of shipborne radars), and has multi-scenario adaptability.

[0049] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple. For related parts, reference can be made to the description of the method part.

[0050] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A double-helical oscillating hydraulic cylinder with a fixed cantilever structure, characterized in that, It includes a cylinder block, a cantilever screw, and a hollow screw. A channel extending along its axial direction is defined within the cylinder block. The middle section of the cantilever screw is disposed within the channel and extends along the axial direction of the channel. The hollow screw, which is also located within the channel, is sleeved on the outer periphery of the cantilever screw, and the hollow screw divides the channel into a first chamber and a second chamber that are spaced apart from each other. The inner wall surface of one end of the hollow screw is in threaded engagement with the outer wall surface of the cantilever screw to form a first-stage thread pair, and the outer wall surface of the other end of the hollow screw is in threaded engagement with the inner wall surface of the cylinder block to form a second-stage thread pair. The first-stage thread pair and the second-stage thread pair have opposite helix directions. First oil inlet holes and second oil inlet holes are respectively opened at the front and rear ends of the cantilever screw. First oil outlet holes are opened on the rod body of the cantilever screw located within the first chamber, and second oil outlet holes are opened on the rod body of the cantilever screw located within the second chamber. The first oil inlet hole communicates with the first chamber through a first oil delivery passage axially opened within the cantilever screw and via the first oil outlet hole. The second oil inlet hole communicates with the second chamber through a second oil delivery passage axially opened within the cantilever screw and via the second oil outlet hole. A first end cover that closes the first chamber is sleeved on the front side of the cantilever screw, and a second end cover that closes the second chamber is sleeved on the rear side of the cantilever screw.

2. The double-helix swing hydraulic cylinder adopting a fixed cantilever structure according to claim 1, wherein, A first axial groove is opened on the outer periphery of the front side of the cantilever screw, and a second axial groove is opened on the outer periphery of the rear side. A first shaft circlip is installed within the first axial groove, and a second shaft circlip is installed within the second axial groove. A first clamping groove is opened on the inner wall of the front side of the cylinder block, and a second clamping groove is opened on the inner wall of the rear side. A first elastic clamping ring is installed within the first clamping groove, and a second elastic clamping ring is installed within the second clamping groove. The first shaft circlip and the first elastic clamping ring jointly act to axially position the first end cover, and the second shaft circlip and the second elastic clamping ring jointly act to axially position the second end cover. A first thrust bearing is installed between the first end cover and the first shaft circlip, and a first radial bearing is installed between the first end cover and the cantilever screw. A second thrust bearing is installed between the second end cover and the second shaft circlip, and a second radial bearing is installed between the second end cover and the cantilever screw. The two thrust bearings are used to bear the axial load of the cantilever screw, and the two radial bearings are used to bear the radial load of the cantilever screw.

3. A double-helix oscillating hydraulic cylinder with a fixed cantilever structure according to claim 1 or 2, characterized in that, First sealing rings are correspondingly installed between the two end covers and the corresponding cantilever screw and between the end covers and the cylinder block.

4. A double-helical oscillating hydraulic cylinder using a fixed cantilever structure according to claim 1, characterized in that, Second sealing rings are correspondingly installed between the hollow screw and the cantilever screw and between the hollow screw and the cylinder block.

5. A double-helical oscillating hydraulic cylinder with a fixed cantilever structure according to claim 1, characterized in that, Key grooves for connecting with the corresponding mounting seats on the respective sides are opened on the outer peripheral surfaces of the front and rear ends of the cantilever screw.

6. A double-helix oscillating hydraulic cylinder using a fixed cantilever structure according to claim 1, characterized in that, A plurality of the first oil outlet holes and a plurality of the second oil outlet holes are respectively circumferentially and evenly opened at the corresponding positions of the rod body of the cantilever screw.

Images