Two-degree-of-freedom joint device

Abstract

The utility model provides a two-degree-of-freedom joint device which comprises a fixed gear shaft extending along a first direction and fixedly supported on a carrier; the input power assemblies are supported on the fixed gear shaft, and the central axis of each input power assembly extends in the second direction perpendicular to the first direction; the output arm is supported on the pair of input power assemblies, and the output arm and the fixed gear shaft are located on the two opposite sides of the pair of input power assemblies respectively in the first direction; wherein the fixed gear shaft comprises a first bevel gear coaxially arranged with the fixed gear shaft, each input power assembly comprises a second bevel gear coaxially arranged with the corresponding input power assembly, and the second bevel gears are meshed with the first bevel gears respectively; the input power assemblies input rotating power around the second direction to the fixed gear shaft so that the corresponding second bevel gear can rotate relative to the first bevel gear, and the output arm responds to the rotating speed difference value of the pair of input power assemblies to rotate around the first direction or the second direction.

Description

Technical Field

[0001] The utility model relates to the field of mechanical arms, in particular to a double-freedom joint device. Background Art

[0002] The current robot arm joints mainly achieve multi-DOF motion output by splicing single-DOF joint modules. Each single-DOF module contains a reducer, a motor and an encoder.

[0003] The overall stiffness of a robotic arm composed of multiple groups of single-degree-of-freedom joints will be less than that of any single-degree-of-freedom joint because they are connected in series. In addition, each single-degree-of-freedom joint is subjected to force independently, and each single-degree-of-freedom joint requires a high safety margin, which cannot fully utilize the performance of the motor in the single-degree-of-freedom joint. Utility Model Content

[0004] In order to solve the above technical problems, the utility model provides a dual-degree-of-freedom joint device, which adopts a pair of parallel-connected input power components to provide rotational power for the output arm, so that the output arm has rotational freedom in a pair of mutually perpendicular directions.

[0005] In one embodiment of the utility model, a dual-degree-of-freedom joint device is provided, comprising:

[0006] A fixed gear shaft, the central axis of which extends along a first direction and is fixedly supported on a carrier;

[0007] a pair of input power assemblies, the pair of input power assemblies being supported on the fixed gear shaft, the central axis of each of the input power assemblies extending along a second direction perpendicular to the first direction;

[0008] an output arm, the output arm being supported by the pair of input power assemblies and being located on opposite sides of the pair of input power assemblies with the fixed gear shaft in the first direction;

[0009] Wherein, the fixed gear shaft comprises a first bevel gear coaxially arranged with the fixed gear shaft, and each of the input power assemblies comprises a second bevel gear coaxially arranged with the input power assembly, and the second bevel gears are respectively meshed with the first bevel gears;

[0010] The input power assembly inputs rotational power about the second direction to the fixed gear shaft to rotate the corresponding second bevel gear relative to the first bevel gear, and the output arm rotates about the first direction or the second direction in response to the rotation speed difference between a pair of input power assemblies.

[0011] In one embodiment, it includes:

[0012] A fixed bracket is sleeved on the fixed gear shaft, and the pair of input power components are supported by the fixed bracket.

[0013] In one embodiment, the fixed gear shaft comprises:

[0014] A nut fixing seat, wherein the nut fixing seat is fixedly mounted on the carrier;

[0015] A fixed shaft, the fixed shaft being supported on the nut fixing seat via a fixing nut;

[0016] The fixed shaft extends axially along the first direction and is threadedly connected to the fixing nut, and the spacing of the first bevel gear relative to the nut fixing seat in the first direction corresponds to the axial position of the fixing nut relative to the fixed shaft.

[0017] In one embodiment, the fixed gear shaft comprises:

[0018] A threaded bearing seat, wherein the fixed shaft is axially supported on the threaded bearing seat via a support bearing, and the fixed shaft and the threaded bearing seat are relatively stationary;

[0019] Wherein, the fixing nut is sleeved on the threaded bearing seat and is threadably connected to the threaded bearing seat.

[0020] In one embodiment, the nut fixing seat limits the fixing nut in the first direction.

[0021] In one embodiment, the fixing bracket is fixedly mounted on the nut fixing seat.

[0022] In one embodiment, the input power assembly comprises:

[0023] An input rotor and an input stator are coaxially arranged, wherein the input rotor is rotatably supported by the input stator, and the input rotor is supported by the fixed bracket;

[0024] A stator fixing flange, wherein the stator fixing flange is fixedly connected to the input stator, and the output arm is fixedly supported between a pair of the stator fixing flanges;

[0025] The second bevel gear is fixedly connected to the input rotor so as to be rotationally driven by the input rotor, and a pair of the second bevel gears are arranged opposite to each other.

[0026] In one embodiment, the input power assembly comprises:

[0027] A bearing locating seat, the input rotor is supported on the bearing locating seat via a rotor bearing, and the rotor bearing has the freedom to move axially relative to the bearing locating seat in the second direction;

[0028] A positioning thread sleeve, wherein the positioning thread sleeve is sleeved on the input rotor and is threadably matched with the bearing locating seat. The relative positions of the positioning thread sleeve and the rotor bearing in the second direction are fixed. The spacing of the second bevel gear relative to the bearing locating seat in the second direction corresponds to the axial position of the positioning thread sleeve relative to the bearing locating seat.

[0029] In one embodiment, the input power assembly comprises:

[0030] An elastic member is installed between the bearing locating seat and the second bevel gear in the second direction.

[0031] In one embodiment, the bearing locator supports the output arm in the first direction.

[0032] It can be seen from the above technical solution that in this embodiment, a fixed gear shaft 4 is used as a supporting base, and a pair of relatively arranged input power components 2 are used to realize rotational input. By adjusting the rotation speed and direction of a pair of input power components 2, the output arm 1 can be rotated around the first direction L1 or the second direction L2, thereby realizing the adjustment of dual degrees of freedom.

[0033] Among them, a pair of input power components 2 are respectively meshed with fixed gear shafts 4, and the rotation direction of the output arm 1 does not respond to the rotation of a single input power component 2, but responds to the rotation speed difference of a pair of input power components 2, thereby realizing parallel connection of the input power components instead of series connection. Through this form of parallel connection, the performance of the input power group can be fully utilized, and the stiffness of the overall joint is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The following drawings are only used to illustrate and explain the present invention, and do not limit the scope of the present invention.

[0035] Figure 1 It is a structural schematic diagram of a double-degree-of-freedom joint device of the utility model.

[0036] Figure 2 It is a structural schematic diagram of the fixed gear shaft in the utility model.

[0037] Figure 3 It is a result schematic diagram of the power input component in the utility model. DETAILED DESCRIPTION

[0038] In order to have a clearer understanding of the technical features, purposes and effects of the utility model, the specific implementation of the utility model is now described with reference to the accompanying drawings, in which the same reference numerals represent the same parts.

[0039] In this document, “exemplary” means “serving as an example, instance or illustration”, and any diagram or implementation described in this document as “exemplary” should not be interpreted as a more preferred or more advantageous technical solution.

[0040] In order to simplify the drawings, only the parts related to the utility model are schematically shown in each figure, and do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked.

[0041] In this document, “upper”, “lower”, “front”, “back”, “left”, “right”, etc. are only used to indicate the relative position relationship between related parts, rather than to limit the absolute positions of these related parts.

[0042] In this article, "first", "second", etc. are only used to distinguish each other, and do not indicate the importance and order, or the premise of each other's existence.

[0043] In this article, "equal", "same" and the like are not strictly limited in the mathematical and / or geometric sense, but also include errors that can be understood by those skilled in the art and are allowed in manufacturing or use. Unless otherwise specified, the numerical ranges herein include not only the entire range within its two endpoints, but also several sub-ranges contained therein.

[0044] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0045] In order to solve the problems in the prior art, the utility model provides a dual-degree-of-freedom joint device, which adopts a pair of parallel-connected input power components to provide rotational power for an output arm, so that the output arm has rotational freedom in a pair of mutually perpendicular directions.

[0046] like Figures 1 to 3 As shown, one embodiment of the utility model provides a dual-degree-of-freedom joint device, comprising:

[0047] A fixed gear shaft 4, wherein the central axis of the fixed gear shaft 4 extends along the first direction L1 and is fixedly supported on the carrier;

[0048] A pair of input power assemblies 2, the pair of input power assemblies 2 are supported by a fixed gear shaft 4, and the central axis of each input power assembly 2 extends along a second direction L2 perpendicular to the first direction L1;

[0049] An output arm 1, the output arm 1 is supported by a pair of input power assemblies 2, and is located on opposite sides of the pair of input power assemblies 2 with the fixed gear shaft in a first direction L1;

[0050] The fixed gear shaft 4 includes a first bevel gear 405 coaxially arranged with the fixed gear shaft 4, and each input power assembly 2 includes a second bevel gear 209 coaxially arranged with the input power assembly 2, and the second bevel gears 209 are respectively meshed with the first bevel gears 405;

[0051] The input power assembly 2 inputs rotational power around the second direction L2 to the fixed gear shaft 4 so that the corresponding second bevel gear 209 rotates relative to the first bevel gear 405, and the output arm 1 rotates around the first direction L1 or the second direction L2 in response to the rotation speed difference between a pair of input power assemblies 2.

[0052] In this embodiment, a fixed gear shaft 4 is used as a supporting base, and a pair of relatively arranged input power assemblies 2 are used to realize rotational input. By adjusting the rotation speed and direction of a pair of input power assemblies 2, the output arm 1 can be rotated around the first direction L1 or the second direction L2, thereby realizing the adjustment of dual degrees of freedom.

[0053] Among them, a pair of input power components 2 are respectively meshed with fixed gear shafts 4, and the rotation direction of the output arm 1 does not respond to the rotation of a single input power component 2, but responds to the rotation speed difference of a pair of input power components 2, thereby realizing parallel connection of the input power components instead of series connection. Through this form of parallel connection, the performance of the input power group can be fully utilized, and the stiffness of the overall joint is greatly improved.

[0054] Specifically, Figure 1 As shown, in this embodiment, a pair of input power assemblies 2 are respectively meshed with the first bevel gear 405 of the fixed gear shaft 4 through a second bevel gear 209, and the pair of input power assemblies 2 are supported in a plane perpendicular to the axial direction of the fixed gear shaft 4, that is, the first direction L1, and the central axis direction of the input power assembly 2 can be any direction in the plane. And the second direction L2 is radially distributed around the first direction L1.

[0055] Through the setting of bevel gears, the central axis direction of a pair of input power components 2 can be set in a plane perpendicular to the axial direction of the fixed gear shaft 4. Compared with the series connection arrangement, the structure of the entire joint device is more compact, and the axial length in the first direction L1 is greatly reduced, while the stiffness of the entire joint device is improved.

[0056] The rotation input of each input power assembly 2 is relatively independent and does not interfere with each other. Therefore, a pair of input power assemblies 2 can have different rotation speeds and rotation directions to achieve the adjustment of the rotation direction of the output arm 1.

[0057] For example, when a pair of input power assemblies 2 input rotational power at the same rotation speed and opposite rotation directions, the directions of the central axes of the pair of input power assemblies 2 remain consistent, and the relative positions of the pair of input power assemblies 2 remain unchanged. The pair of input power assemblies 2 synchronously provide torque in the same direction to the output arm 1, so that the output arm 1 rotates around the second direction L2 to achieve pitch adjustment of the output arm 1.

[0058] For example, when a pair of input power assemblies 2 input rotational power at different rotation speeds and opposite rotation directions, the central axis directions of the pair of input power assemblies 2 form an angle in a plane perpendicular to the first direction L1, and the pair of input power assemblies 2 provide different torques around the first direction L1 to the output arm 1, so that the output arm 1 rotates around the first direction L1, thereby realizing yaw adjustment of the output arm 1.

[0059] The joint device of this embodiment includes:

[0060] The fixed bracket 3 is sleeved on the fixed gear shaft 4 , and a pair of input power components 2 are supported on the fixed bracket 3 .

[0061] In a specific example, if Figure 2 As shown, the fixed gear shaft 4 includes:

[0062] A nut fixing seat 401, wherein the nut fixing seat 401 is fixedly mounted on the carrier;

[0063] A fixed shaft 406, the fixed shaft 406 is supported on the nut fixing seat 401 via a fixing nut 402;

[0064] The fixed shaft 406 extends axially along the first direction L1 and is threadedly connected to the fixing nut 402 . The spacing of the first bevel gear 405 relative to the nut fixing seat 401 in the first direction L1 corresponds to the axial position of the fixing nut 402 relative to the fixed shaft 406 .

[0065] Specifically, the fixed gear shaft 4 includes:

[0066] The threaded bearing seat 403, the fixed shaft 406 is axially supported on the threaded bearing seat 403 via the support bearing 404, and the fixed shaft 406 and the threaded bearing seat 403 are relatively stationary;

[0067] The fixing nut 402 is sleeved on the threaded bearing seat 403 and is threadedly connected to the threaded bearing seat 403 .

[0068] The nut fixing seat 401 can be realized in a ring shape, the fixed shaft 406 is axially installed on the adapter fixing seat 407, the adapter fixing seat 407 is located in the inner ring of the nut fixing seat 401, the support bearing 404 is sleeved on the fixed shaft 406, and the fixed shaft 406 is fixedly supported on the threaded bearing seat 403.

[0069] In this embodiment, what is fixed to the carrier is not the fixing shaft 406 but the nut fixing seat 401. Preferably, the nut fixing seat 401 fixes the nut 402 in the upper limit position in the first direction L1.

[0070] When the fixing nut 402 is threadedly rotated relative to the nut fixing seat 401, in the first direction, the positions of the nut fixing seat 401 and the fixing nut 402 will not change, but the fixing shaft 406 will produce axial movement relative to the nut fixing seat 401 and the fixing nut 402, thereby driving the axial spacing of the first bevel gear 405 fixed on the fixing shaft 406 relative to the nut fixing seat 401 to change.

[0071] The change of the axial distance between the first bevel gear 405 and the nut fixing seat 401 can adjust the distance between the first bevel gear 405 and the second bevel gear 209 of the input power assembly 2 in the first direction L1 to adjust the matching clearance between the first bevel gear 405 and the second bevel gear 209 in the first direction L1.

[0072] like Figure 1 As shown, the fixing bracket 3 is fixedly mounted on the nut fixing seat 401 .

[0073] like Figure 1 and Figure 3 As shown, the input power assembly 2 includes:

[0074] An input rotor 201 and an input stator 202 are coaxially arranged, the input rotor 201 is rotatably supported by the input stator 202, and the input rotor 201 is supported by a fixed bracket 3;

[0075] A stator fixing flange 203, the stator fixing flange 203 is fixedly connected to the input stator 202, and the output arm 1 is fixedly supported between a pair of stator fixing flanges 203;

[0076] The second bevel gear 209 is fixedly connected to the input rotor 201 so as to be rotationally driven by the input rotor 201 . A pair of second bevel gears 209 are disposed opposite to each other.

[0077] The combination of the input rotor 201 and the input stator 202 may be a servo motor. The input rotor 201 may generate an angular displacement relative to the input stator 202 and identify the displacement angle and torque.

[0078] In this example, the input end of the input power assembly 2 is located outside the entire joint, while the pair of second bevel gears 209 are located inside the entire joint. Similarly, the output arm 1 also faces the outside of the entire joint.

[0079] A pair of stator fixing flanges 203 are formed in the form of claws, and the output arm 1 is fixedly supported between the pair of stator fixing flanges 203. The input rotor 201 is supported on the fixing bracket 3, and the output arm 1 is fixedly supported on the input stator 202, thereby realizing that the output arm 1 is integrally connected with the input stator 202 of the input power assembly 2, and is isolated from the fixed gear shaft 4.

[0080] Wherein, the input power assembly 2 comprises:

[0081] A bearing locating seat 206, the input rotor 201 is supported on the bearing locating seat 206 via a rotor bearing 207, and the rotor bearing 207 has the freedom to move axially relative to the bearing locating seat 206 in the second direction L2;

[0082] The positioning thread sleeve 204 is sleeved on the input rotor 201 and threadedly matched with the bearing locating seat 206. The relative position of the positioning thread sleeve 204 and the rotor bearing 207 in the second direction L2 is fixed. The spacing of the second bevel gear 209 relative to the bearing locating seat 206 in the second direction L2 corresponds to the axial position of the positioning thread sleeve 204 relative to the bearing locating seat 206.

[0083] The positioning thread sleeve 204 is not fixedly connected to the rotor bearing 207, but is axially limited by the shaft sleeve 205, so that the relative position of the positioning thread sleeve 204 and the rotor bearing 207 in the second direction L2 is fixed and unchanged. When the axial position of the positioning thread sleeve 204 relative to the bearing locating seat 206 is changed by the rotation of the thread, the axial position of the rotor bearing 207 relative to the bearing locating seat 206 in the second direction L2 is changed, thereby changing the axial position of the integrally connected input rotor 201 relative to the bearing locating seat 206 in the second direction L2. The second bevel gear 209 is fixedly connected to the input rotor 201, so the spacing of the second bevel gear 209 relative to the bearing locating seat 206 in the second direction L2 corresponds to the axial position of the positioning thread sleeve 204 relative to the bearing locating seat 206.

[0084] By adjusting the distance between the second bevel gear 209 and the bearing locating seat 206 in the second direction L2, the matching clearance between the second bevel gear 209 and the first bevel gear 405 can be adjusted in the second direction L2.

[0085] Preferably, the input power assembly 2 comprises:

[0086] The elastic member 208 is installed between the bearing positioning seat 206 and the second bevel gear 209 in the second direction L2.

[0087] The bearing locating seat 206 supports the output arm 1 in the first direction L1.

[0088] In this example, the first bevel gear 405 and the second bevel gear 209 have complementary cone angles. In a specific example, the cone angles of the first bevel gear 405 and the second bevel gear 209 are both 45°.

[0089] It can be seen from the above technical solution that in this embodiment, a fixed gear shaft 4 is used as a supporting base, and a pair of relatively arranged input power components 2 are used to realize rotational input. By adjusting the rotation speed and direction of a pair of input power components 2, the output arm 1 can be rotated around the first direction L1 or the second direction L2, thereby realizing the adjustment of dual degrees of freedom.

[0090] Among them, a pair of input power components 2 are respectively meshed with fixed gear shafts 4, and the rotation direction of the output arm 1 does not respond to the rotation of a single input power component 2, but responds to the rotation speed difference of a pair of input power components 2, thereby realizing parallel connection of the input power components instead of series connection. Through this form of parallel connection, the performance of the input power group can be fully utilized, and the stiffness of the overall joint is greatly improved.

[0091] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the utility model, and are not intended to limit the scope of protection of the utility model. Any equivalent implementation plans or changes that do not deviate from the technical spirit of the utility model, such as combination, division or repetition of features, should be included in the scope of protection of the utility model.

Claims

1. A dual-degree-of-freedom joint device, characterized in that: include: A fixed gear shaft, the central axis of which extends along a first direction and is fixedly supported on a carrier; a pair of input power assemblies, the pair of input power assemblies being supported on the fixed gear shaft, the central axis of each of the input power assemblies extending along a second direction perpendicular to the first direction; an output arm, the output arm being supported by the pair of input power assemblies and being located on opposite sides of the pair of input power assemblies with the fixed gear shaft in the first direction; Wherein, the fixed gear shaft comprises a first bevel gear coaxially arranged with the fixed gear shaft, each of the input power assemblies comprises a second bevel gear coaxially arranged with the input power assembly, and the second bevel gears are respectively meshed with the first bevel gears; The input power assembly inputs a rotational power about the second direction to the fixed gear shaft, so that the corresponding second bevel gear rotates relative to the first bevel gear, and the output arm rotates about the first direction or the second direction in response to the rotation speed difference of a pair of input power assemblies; The fixed gear shaft comprises: A nut fixing seat, wherein the nut fixing seat is fixedly mounted on the carrier; A fixed shaft, the fixed shaft being supported on the nut fixing seat via a fixing nut; The fixed shaft extends axially along the first direction and is threadedly connected to the fixing nut, and the spacing of the first bevel gear relative to the nut fixing seat in the first direction corresponds to the axial position of the fixing nut relative to the fixed shaft.

2. The dual-degree-of-freedom joint device according to claim 1, characterized in that: include: A fixed bracket is sleeved on the fixed gear shaft, and the pair of input power components are supported by the fixed bracket.

3. The dual-degree-of-freedom joint device according to claim 2, characterized in that: The fixed gear shaft comprises: A threaded bearing seat, wherein the fixed shaft is axially supported on the threaded bearing seat via a support bearing, and the fixed shaft and the threaded bearing seat are relatively stationary; Wherein, the fixing nut is sleeved on the threaded bearing seat and is threadably connected to the threaded bearing seat.

4. The dual-degree-of-freedom joint device according to claim 2, characterized in that: The nut fixing seat limits the fixing nut in the first direction.

5. The dual-degree-of-freedom joint device according to claim 2, characterized in that: The fixing bracket is fixedly mounted on the nut fixing seat.

6. The dual-degree-of-freedom joint device according to claim 2, characterized in that: The input power assembly comprises: An input rotor and an input stator are coaxially arranged, wherein the input rotor is rotatably supported by the input stator, and the input rotor is supported by the fixed bracket; A stator fixing flange, wherein the stator fixing flange is fixedly connected to the input stator, and the output arm is fixedly supported between a pair of the stator fixing flanges; The second bevel gear is fixedly connected to the input rotor so as to be rotationally driven by the input rotor, and a pair of the second bevel gears are arranged opposite to each other.

7. The dual-degree-of-freedom joint device according to claim 6, characterized in that: The input power assembly comprises: A bearing locating seat, the input rotor is supported on the bearing locating seat via a rotor bearing, and the rotor bearing has the freedom to move axially relative to the bearing locating seat in the second direction; A positioning thread sleeve, wherein the positioning thread sleeve is sleeved on the input rotor and is threadably matched with the bearing locating seat. The relative positions of the positioning thread sleeve and the rotor bearing in the second direction are fixed. The spacing of the second bevel gear relative to the bearing locating seat in the second direction corresponds to the axial position of the positioning thread sleeve relative to the bearing locating seat.

8. The dual-degree-of-freedom joint device according to claim 7, characterized in that: The input power assembly comprises: An elastic member is installed between the bearing locating seat and the second bevel gear in the second direction.

9. The dual-degree-of-freedom joint device according to claim 7, characterized in that: The bearing locating seat supports the output arm in the first direction.

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