Linear stepping motor, bionic finger, and bionic dextellar hand

Abstract

A linear stepping motor, a bionic finger, and a bionic dextellas hand, the linear stepping motor comprises an outer housing (10), a stator (6) provided inside the outer housing (10) and fixed to the inner wall of the outer housing (10), a drive nut (1) provided rotatably inside the outer housing (10) and drilled into the inner ring of the stator (6), a rotor (7) wound around the outer circumference of the drive nut (1), and a lead screw (2), which is provided slidingly in the outer housing (10) along the axial direction of the outer housing (10), with one end of the lead screw (2) protruding from the outer housing (10), the drive nut (1) being screwed onto the lead screw (2), and when the stator (6) is energized, the rotor (7) and the drive nut (1) are rotated together, causing the lead screw (2) to extend and retract linearly relative to the outer housing (10).

Description

Technical Field

[0001] This application claims the priority of a Chinese patent application filed with the China National Intellectual Property Administration on May 30, 2024, with the application number 202410686173.7, and all the contents of the above application are incorporated herein by reference.

[0002] This application relates to the technical field of manipulators, for example, linear stepping motors, ionic fingers and ionic dexterous hands.

Background Art

[0003] An ionic dexterous hand is a complex device integrating multiple ionic fingers, and is intended to simulate the overall functions and flexibility of a human hand. With advanced control algorithms and sensing technologies, an ionic dexterous hand can perform precise object manipulation and grasping in a complex operating environment.

[0004] Currently, the grasping operation of an ionic finger is realized by one motor rotating multiple finger joints through tendon wires. In this driving mode, continuous power input to the motor is required to maintain the grasping posture, and there are problems of poor transmission efficiency and positioning accuracy, low space utilization rate and low output power.

Summary of the Invention

[0005] This application provides a linear stepping motor having self-locking performance, higher transmission efficiency and positioning accuracy, suitable for controlling the high-speed and high-precision grasping operations of ionic fingers and ionic dexterous hands, with a compact and delicate structure, and being advantageous for miniaturized design. This invention provides a bionic finger and a bionic dextellas hand that realize the gripping operation of the bionic finger using a linear stepping motor, and in which the outer housing of the linear stepping motor is provided integrally with the outer housing of the drive finger joint, thereby improving space utilization and motor power.

[0006] As the first aspect, in this application, The outer casing, and the part provided inside the outer casing, A stator fixed to the inner wall of the outer casing, A drive nut is provided rotatably within the outer housing and drilled into the inner ring of the stator, A rotor is wound around the outer circumference of the aforementioned drive nut, A lead screw, which is mounted on the outer housing so as to slide along the axial direction of the outer housing, with one end of the lead screw protruding from the outer housing, a drive nut screwed onto the lead screw, and when the stator is energized, the rotor and the drive nut are rotated together, thereby linearly extending and retracting the lead screw relative to the outer housing, and the lead screw, Equipped with, We provide linear stepping motors.

[0007] Preferably, the linear stepping motor is A radial bearing, wherein the drive nut is provided at one end away from the protrusion of the lead screw, the inner ring of the radial bearing is fitted onto the outer circumference of the drive nut, and the outer ring of the radial bearing is fixed to the inner wall of the outer housing, A thrust bearing wherein a thrust step is provided at one end of the drive nut near the protrusion of the lead screw, an inner flange is provided at an opening in the outer housing corresponding to the protrusion of the lead screw, the thrust shaft plate of the thrust bearing abuts against the thrust step, and the thrust seat plate of the thrust bearing is fixed to the inner flange, To further prepare.

[0008] Preferably, the linear stepping motor further comprises a locking block that is engaged with the outer housing, protrudes into the inner cavity of the outer housing, and is pressed against one end of the radial bearing away from the protrusion of the lead screw.

[0009] Preferably, a position-restricting step is provided at one end of the drive nut away from the protrusion of the lead screw, and the inner ring of the radial bearing closer to the protrusion of the lead screw is pressed against the position-restricting step.

[0010] Preferably, the inner diameter of the inner flange is smaller than the inner diameter of the thrust bearing, and the inner flange completely shields the thrust bearing so as to completely protect the thrust bearing.

[0011] Preferably, the radial bearing is a deep groove ball bearing.

[0012] Preferably, the thrust bearing is a thrust roller bearing or a thrust sliding bearing.

[0013] Preferably, the rotor is made of magnetic steel, The stator comprises an iron core fixed to the inner wall of the outer housing and having a winding groove on the side facing the outer housing, and a coil wound in the winding groove.

[0014] Preferably, the drive nut is made of a polymer plastic material.

[0015] Preferably, the lead screw is made of a metal alloy material.

[0016] As a second aspect, the present invention provides a bionic finger comprising a terminal finger joint and a plurality of drive finger joints that are sequentially rotatably connected, wherein the drive finger joints are equipped with the linear stepping motor described above, and one end of the lead screw protruding from the outer housing is transmitted to an adjacent drive finger joint or terminal finger joint to rotate and drive the drive finger joint or terminal finger joint, and the outer housing of the linear stepping motor is provided integrally with the outer housing of the drive finger joint.

[0017] As a third aspect, the present invention provides a bionic dextellas hand comprising the bionic finger and palm structure described above, wherein the bionic finger and the palm structure are movably connected. [Brief explanation of the drawing]

[0018] [Figure 1] This is a cross-sectional view of a partial structure of a linear stepper according to the present invention. [Explanation of Symbols]

[0019] In the diagram: 10...Outer housing, 101...Inner flange, 1... Drive nut, 11... Thrust step, 12... Position regulating step, 2... Lead screw, 3... Radial bearing, 31... Inner ring, 32... Outer ring, 4... Thrust bearing, 41... Thrust shaft plate, 42... Thrust seat plate, 5... Lock block, 6... Stator, 61... Iron core, 610... Winding groove, 62... Coil, 7... Rotor. [Modes for carrying out the invention]

[0020] The present application will be described below in connection with the drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of interpreting the present application and do not limit the present application. Incidentally, for convenience of explanation, only the parts related to the present application are shown in the drawings, not all structures.

[0021] In the description of the present application, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed to" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated, a mechanical connection, an electrical connection, directly connected, indirectly connected through an intermediate medium, or the communication between two elements or the interaction relationship between two elements. A person skilled in the art can understand the specific meanings of the above terms in the present application in specific situations.

[0022] In the present application, unless otherwise clearly defined and limited, the fact that the first feature is "above" or "below" the second feature may include that the first feature and the second feature are in direct contact, or may include that the first feature and the second feature are not in direct contact and are in contact through other features therebetween. Further, the fact that the first feature is "above", "above" and "upper surface" of the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The fact that the first feature is "below", "below" and "lower surface" of the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature.

[0023] In the description of this embodiment, the orientation or positional relationship of terms such as "upper", "lower", "right", "left", etc. is based on the orientation or positional relationship shown in the drawings, and is only for facilitating the description and simplifying the operation, and does not indicate or imply that such a device or element must have a specific orientation and must be configured and operated from a specific orientation, so it should not be understood as limiting the present application. Also, the terms "first" and "second" are only for distinction in the description and have no special meaning.

[0024] In this embodiment, a bio-ionic dexterous hand is provided, which includes a bio-ionic finger and a palm structure, and the bio-ionic finger and the palm structure are movably connected. The bio-ionic finger includes a terminal finger joint and a plurality of driving finger joints that are sequentially rotationally connected, and the driving finger joint includes a linear stepping motor, and the linear stepping motor is transmission-connected to an adjacent driving finger joint or a terminal finger joint to rotationally drive the latter.

[0025] As shown in Figure 1, the linear stepping motor comprises an outer housing 10, a stator 6, a rotor 7, a drive nut 1, and a lead screw 2, all of which are located inside the outer housing 10. The stator 6 is fixed to the inner wall of the outer housing 10, the drive nut 1 is rotatably mounted inside the outer housing 10 and is drilled into the inner ring of the stator 6, the rotor 7 is wound around the outer circumference of the drive nut 1, and the lead screw 2 is slidably mounted on the outer housing 10 along the axial direction of the outer housing 10, with one end of the lead screw 2 (i.e., the lead screw in Figure 1) The upper end of the rotor 2 protrudes from the outer housing 10 and is power-driven to an adjacent drive finger joint or end finger joint. The drive nut 1 is screwed onto the lead screw 2, and when the stator 6 is energized, the rotor 7 and the drive nut 1 are rotated together, causing the lead screw 2 to extend and retract linearly relative to the outer housing 10. This causes the drive finger joint or end finger joint connected to it to rotate, and the outer housing 10 of the linear stepping motor is provided integrally with the outer housing of the drive finger joint.

[0026] In the bionic finger and bionic dextellas hand according to this embodiment, the gripping operation of the bionic finger is realized by a linear stepping motor. Firstly, the linear stepping motor rotates the rotor 7 and the drive nut 1 together by energizing the stator 6, and the drive nut 1 slides the lead screw 2, which is screwed to it, against the outer housing 10, thereby realizing the conversion of rotational power to linear power. Self-locking between the drive nut 1 and the lead screw 2 eliminates the need for continuous power input, enabling the extension and retraction positions to be maintained. Moreover, by extending and retracting the lead screw 2 via the drive nut 1, rigidity is increased, and transmission efficiency and positioning accuracy can be effectively improved, making it well-suited for controlling the high-speed and high-precision gripping operation of the bionic finger and bionic dextellas hand. Furthermore, since the drive nut 1 functions as the rotation axis of the linear stepping motor, the structure of the linear stepping motor is simplified, making the structure more compact and sophisticated, which is advantageous for miniaturization and application to the bionic finger. Secondly, the outer casing 10 of the linear stepping motor is integrated with the outer casing of the drive finger joint. In other words, the outer casing 10 of the linear stepping motor functions as the outer casing structure of the bionic finger, resulting in a more compact overall structure, improved space utilization, and the ability to install a linear stepping motor with higher output power within a limited space. This leads to improved output power and a larger, more stable gripping force.

[0027] For example, the rotor 7 is made of magnetic steel and is fastened to the outer circumference of the drive nut 1 via adhesive to form a single unit. As shown in Figure 1, the stator 6 comprises an iron core 61 which is firmly fixed to the inner wall of the outer housing 10 and has a winding groove 610 on the side facing the outer housing 10, and a coil 62 which is wound in the winding groove 610. When AC power is supplied to the coil 62, the rotor 7 and the drive nut 1 are rotated together.

[0028] For example, as shown in Figure 1, the drive nut 1 is rotatably mounted on the outer housing 10 via a bearing. The linear stepping motor further comprises a radial bearing 3 and a thrust bearing 4.

[0029] As shown in Figure 1, the radial bearing 3 is provided on the drive nut 1 at one end away from the protrusion of the lead screw 2, the inner ring 31 of the radial bearing 3 is tightly fitted around the outer circumference of the drive nut 1, and the outer ring 32 of the radial bearing 3 is fixed to the inner wall of the outer housing 10, so that the radial bearing 3 can bear the radial load of the drive nut 1.

[0030] For example, as shown in Figure 1, the linear stepping motor further includes a lock block 5, which is engaged with the outer housing 10 and protrudes into the inner cavity of the outer housing 10. A position-restricting step 12 is provided at one end of the drive nut 1 away from the protrusion of the lead screw 2. The lock block 5 is pressed against the side of the outer ring 32 of the radial bearing 3 away from the protrusion of the lead screw 2, and the side of the inner ring 31 of the radial bearing 3 closer to the protrusion of the lead screw 2 is pressed against the position-restricting step 12. This locks the radial bearing 3 between the outer housing 10 and the drive nut 1. Furthermore, if maintenance and adjustment are required, the radial bearing 3 can be removed by removing the lock block 5.

[0031] In this embodiment, the radial bearing 3 is a deep groove ball bearing. In other embodiments of the present invention, the radial bearing 3 may be an angular contact ball bearing, a needle roller bearing, or the like.

[0032] As shown in Figure 1, the thrust bearing 4 is provided at one end of the drive nut 1 closest to the protrusion of the lead screw 2, a thrust step 11 is provided at the end of the drive nut 1 closest to the protrusion of the lead screw 2, an inner flange 101 is provided at the opening in the outer housing 10 corresponding to the protrusion of the lead screw 2, the thrust shaft plate 41 of the thrust bearing 4 abuts against the thrust step 11, and the thrust seat plate 42 of the thrust bearing 4 is fixed to the inner flange 101, so that the thrust bearing 4 can bear the axial load of the drive nut 1.

[0033] The linear stepping motor is configured to drive the gripping motion of the bionic finger, and the resistance to this motion is mainly present in the retraction phase of the lead screw 2. Therefore, the axial load transmitted by the lead screw 2 via the drive nut 1 to one end near the opening of the outer housing 10 is greatest. By providing a thrust bearing 4 here, the unidirectional axial force generated during the gripping process can be effectively withstood, increasing the yield strength, and the thrust bearing 4 and radial bearing 3 work together to achieve a dual action of centering and bearing.

[0034] As shown in Figure 1, the inner diameter of the inner flange 101 is smaller than the inner diameter of the thrust bearing 4, and the inner flange 101 completely shields the thrust bearing 4 so as to completely protect it.

[0035] For example, the thrust bearing 4 may be a thrust roller bearing or a thrust sliding bearing.

[0036] For example, the drive nut 1 may be made from a polymeric plastic material such as polytetrafluoroethylene or polyurethane, which has excellent high-temperature resistance and wear resistance. The lead screw 2 is made from a metal alloy material such as S45C steel or SUJ2 steel, which has high strength, wear resistance, and high-temperature resistance. By combining the material selections of the drive nut 1 and the lead screw 2, the transmission efficiency between them can be increased, structural wear can be reduced, and the service life of the linear stepping motor can be extended.

[0037] For example, as shown in Figure 1, the outer housing 10 is configured as a cylindrical structure, the extension and retraction direction of the lead screw 2 is the same as the axial direction of the outer housing 10, and the outer shape of the cylindrical structure of the outer housing 10 conforms to the finger joint shape of the bionic finger.

Claims

1. The outer casing (10), and provided inside the outer casing (10), A stator (6) is fixed to the inner wall of the outer housing (10), A drive nut (1) is rotatably mounted within the outer housing (10) and drilled into the inner ring of the stator (6), A rotor (7) is wound around the outer circumference of the drive nut (1), A lead screw (2) is provided so as to slide on the outer housing (10) along the axial direction of the outer housing (10), one end of the lead screw (2) protrudes from the outer housing (10), the drive nut (1) is screwed onto the lead screw (2), and when the stator (6) is energized, the rotor (7) and the drive nut (1) are rotated together, causing the lead screw (2) to extend and retract linearly relative to the outer housing (10). Equipped with, Linear stepping motor.

2. A radial bearing (3) is provided on the drive nut (1) at one end away from the protrusion of the lead screw (2), the inner ring (31) of the radial bearing (3) is fitted onto the outer circumference of the drive nut (1), and the outer ring (32) of the radial bearing (3) is fixed to the inner wall of the outer housing (10), A thrust bearing (4), wherein the drive nut (1) has a thrust step (11) at one end near the protrusion of the lead screw (2), the outer housing (10) has an inner flange (101) at an opening corresponding to the protrusion of the lead screw (2), the thrust shaft plate (41) of the thrust bearing (4) abuts against the thrust step (11), and the thrust seat plate (42) of the thrust bearing (4) is fixed to the inner flange (101), and the thrust bearing (4), Furthermore, A linear stepping motor according to claim 1.

3. The system further comprises a lock block (5) that is engaged with the outer housing (10), protrudes into the inner cavity of the outer housing (10), and is pressed against one end of the outer ring (32) of the radial bearing (3) away from the protrusion of the lead screw (2), The linear stepping motor according to claim 2.

4. A position-restricting step (12) is provided at one end of the drive nut (1) away from the protrusion of the lead screw (2), and the inner ring (31) of the radial bearing (3) is pressed against the position-restricting step (12) on the side closer to the protrusion of the lead screw (2). The linear stepping motor according to claim 3.

5. The inner diameter of the inner flange (101) is smaller than the inner diameter of the thrust bearing (4), and the inner flange (101) completely shields the thrust bearing (4). The linear stepping motor according to claim 2.

6. The radial bearing (3) employs a deep groove ball bearing. The linear stepping motor according to claim 2.

7. The thrust bearing (4) employs a thrust roller bearing or a thrust sliding bearing. A linear stepping motor according to claim 2 or 6.

8. The rotor (7) is made of magnetic steel, The stator (6) comprises an iron core (61) fixed to the inner wall of the outer housing (10) and having a winding groove (610) on the side facing the outer housing (10), and a coil (62) wound in the winding groove (610). A linear stepping motor according to any one of claims 1 to 7.

9. The drive nut (1) is made of a polymer plastic material. A linear stepping motor according to any one of claims 1 to 7.

10. The lead screw (2) is made of a metal alloy material. A linear stepping motor according to any one of claims 1 to 7.

11. The linear stepping motor comprises a terminal finger joint and a plurality of drive finger joints that are sequentially rotatably connected, the drive finger joint is equipped with a linear stepping motor as described in any one of claims 1 to 10, one end of the lead screw (2) protruding from the outer housing (10) is transmitted to an adjacent drive finger joint or terminal finger joint to rotate and drive the drive finger joint or terminal finger joint, and the outer housing (10) of the linear stepping motor is provided integrally with the outer housing of the drive finger joint. Bionic Finger.

12. The invention comprises a bionic finger and a palm structure as described in claim 11, wherein the bionic finger and the palm structure are movably connected. Bionic Dexterous Hand.

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