Inner curve type PPU mechanical arm

Abstract

An inner curve type PPU robot is characterized by: further comprising a support block, the support block being disposed inside three support bearings, and an oscillating contour surface being formed on the outer side of the support block, the oscillating contour surface comprising two symmetrically arranged C-shaped contour surfaces, the C-shaped contour surface comprising an arc segment and straight segments at both ends of the arc segment, and the distance of the arc segment from the rotation center of the main shaft being greater than the distance of the straight segments from the rotation center of the main shaft; when the oscillating wheel moves, the three support bearings and the oscillating contour surface are always in contact to form a rolling fit, and the oscillating wheel drives the linkage shaft to move along the C-shaped trajectory. Its advantages are: 1. The support block is set inside the three support bearings. Compared with the cycloidal frame in the prior art, the outer curved surface is changed to the inner curved surface, making the structure more compact and reasonable, and greatly reducing the volume; 2. The C-shaped contour surface includes an arc segment and two straight segments. Compared with the rounded square trajectory in the prior art, the movement of the swing wheel will be more continuous; 3. The support bearing has a higher speed and greater torque when passing through the straight segment, which reduces the influence of gravity and makes the movement more stable. The support bearing has a lower speed and faster speed when passing through the arc segment, which increases the running speed and makes the movement more rapid.

Description

Technical Field

[0001] This invention relates to the field of mechanical automation technology, specifically to an inner curve type PPU robotic arm. Background Technology

[0002] A robotic arm is an automated operating device that can mimic certain movements and functions of a human hand and arm to grasp, move objects, or operate tools according to a fixed program.

[0003] Chinese invention patent application CN 116810807 A discloses a robotic arm that operates using the cycloidal principle. A power source drives the main shaft to rotate eccentrically, enabling the cycloidal wheel to perform cycloidal motion along the cycloidal contour surface within the cycloidal frame. The cycloidal wheel, in turn, drives the linkage shaft to move synchronously along the trajectory of the cycloidal contour surface. During the movement, the cycloidal bearing of the cycloidal wheel is always in contact with the cycloidal contour surface, providing multi-point support, structural stability, and strong load-bearing capacity. Meanwhile, the running trajectory of the linkage shaft is determined by the movement of the cycloidal wheel and the cycloidal frame. There is no gap between the cycloidal bearing and the cycloidal contour surface, resulting in higher movement accuracy and eliminating the problem of mutual impact damage during operation, thus extending service life. In addition, the cycloidal wheel has a built-in deceleration effect, providing sufficient driving force without the need for an additional reducer, further reducing costs.

[0004] How to further optimize the structure and improve the continuity and stability of the robot's movements is a direction that those skilled in the art need to continuously innovate and improve. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention provides an inner curve type PPU robotic arm.

[0006] The technical solution adopted in this invention is: an inner curve type PPU robotic arm, comprising:

[0007] Fixed back panel;

[0008] The spindle is rotatably mounted on a fixed back plate, and its front end has an eccentric shaft that is eccentrically positioned relative to the center of the spindle.

[0009] The power source is mounted on the back of the fixed backplate and drives the connected spindle;

[0010] The oscillating wheel is sleeved outside the eccentric shaft and rotates in conjunction with the eccentric shaft.

[0011] Three support bearings are evenly spaced around the center of the swing wheel;

[0012] The linkage shaft has one end rotatably connected to the swing wheel;

[0013] The support block is disposed inside the three support bearings. The outer side of the support block forms a swing profile surface. The swing profile surface includes two symmetrically arranged C-shaped profile surfaces. The C-shaped profile surface includes an arc segment and straight line segments at both ends of the arc segment. The distance between the arc segment and the rotation center of the main shaft is greater than the distance between the straight line segment and the rotation center of the main shaft.

[0014] The swing wheel can perform a cycloidal motion relative to the support block. During the motion, the three support bearings and the swing contour surface are always in contact to form a rolling fit, and the swing wheel drives the linkage shaft to move along a C-shaped trajectory.

[0015] The rotation center of the linkage shaft, the rotation center of one of the supporting bearings, and the rotation center of the swing wheel are all on the same straight line.

[0016] The center distance between the linkage shaft and the swing wheel is greater than the center distance between the support bearing and the swing wheel.

[0017] The straight segment slopes inward.

[0018] The front of the fixed back plate has a recessed mounting groove, and the support block and the swing wheel are both set in the mounting groove.

[0019] The support block has a central hole that matches the main shaft, and the support block is sleeved on the outside of the main shaft and fixedly connected to the fixed back plate.

[0020] It also includes a track assembly, the track assembly comprising...

[0021] Two Z-axis linear tracks are installed on both sides of the corresponding mounting slots on the fixed back plate;

[0022] The X-axis linear track has two sliding connections at its two ends with two Z-axis linear tracks respectively;

[0023] The slider is slidably mounted on the X-axis linear track and is linked to the linkage shaft.

[0024] The fixed back plate has a perimeter formed on three sides of its front side, and a cover plate is provided on the perimeter.

[0025] The beneficial effects of the present invention are: 1. The support block is set inside the three support bearings. Compared with the cycloidal frame in the prior art, the outer curved surface is changed into the inner curved surface, making the structure more compact and reasonable and greatly reducing the volume.

[0026] 2. The C-shaped contour surface includes an arc segment and two straight segments. Compared with the rounded square trajectory in the prior art, the movement of the swing wheel will be more continuous.

[0027] 3. The support bearing has a higher speed and greater torque when passing through straight sections, reducing the influence of gravity and making the operation smoother. The support bearing has a lower speed and faster speed when passing through circular arc sections, increasing the running speed and making the operation more rapid. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of an inner curve type PPU manipulator according to an embodiment of the present invention.

[0029] Figure 2 This is a schematic diagram of the structure of an inner curve type PPU robot after the cover plate is removed, according to an embodiment of the present invention.

[0030] Figure 3 This is a schematic diagram of the structure of an inner curve type PPU robot after removing the cover plate and slider according to an embodiment of the present invention.

[0031] Figure 4 This is a schematic diagram of the structure of an inner curve type PPU robot arm after removing the cover plate and track assembly according to an embodiment of the present invention.

[0032] Figure 5 This is an exploded structural diagram of the swing wheel, main shaft, and support block according to an embodiment of the present invention.

[0033] Figure 6 This is a schematic diagram of the cooperative structure of the swing wheel, support bearing, and support block in an embodiment of the present invention. Detailed Implementation

[0034] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0035] As shown in the figure, an inner curve type PPU robot includes a fixed back plate 1, a main shaft 2, a power source 3, a swing wheel 4, a support bearing 5, a linkage shaft 6, a support block 7, and a track assembly 8.

[0036] The main shaft 2 is rotatably mounted on the fixed back plate 1, and its front end has an eccentric shaft 21 that is offset from the center of the main shaft 2. The power source 3 is usually a motor, which is mounted on the back of the fixed back plate 1 and drives the main shaft 2.

[0037] The fixed back plate 1 has a recessed mounting groove 11 on its front side, and the support block 7 and the swing wheel 4 are both disposed in the mounting groove 11. The swing wheel 4 is sleeved on the outside of the eccentric shaft 21 and rotates with the eccentric shaft 21. There are 3 support bearings 5, which are disposed on the back of the swing wheel 4 and are evenly spaced around the center of the swing wheel 4. The support block 7 has a center hole 72 that matches the main shaft. The support block 7 is disposed on the back of the swing wheel 4, sleeved on the outside of the main shaft 2 and fixedly connected to the fixed back plate 1. The support block 7 is disposed on the inner side of the 3 support bearings 5.

[0038] The outer side of the support block 7 forms a swing profile surface 71, which is a surface profile calculated based on the motion trajectory of the swing wheel 4 and the support bearing 5. The swing profile surface 71 includes two symmetrically arranged C-shaped profile surfaces. Each C-shaped profile surface includes an arc segment 711 and straight segments 712 at both ends of the arc segment 711. The distance between the arc segment 711 and the rotation center of the main shaft 2 is greater than the distance between the straight segments 712 and the rotation center of the main shaft 2. When the swing wheel 4 moves, the three support bearings 5 ​​are always in contact with the swing profile surface 71 to form a rolling fit. Furthermore, the straight segments 712 are inclined inwards, which, while satisfying the C-shaped profile, further reduces material usage and lowers costs.

[0039] One end of the linkage shaft 6 is rotatably connected to the swing wheel 4, and the rotation center of the linkage shaft 6, the rotation center of one of the support bearings 5, and the rotation center of the swing wheel 4 are all on the same straight line. The center distance between the linkage shaft 6 and the swing wheel 4 is greater than the center distance between the support bearing 5 and the swing wheel 4, further increasing the swing amplitude of the linkage shaft 6. Of course, the linkage shaft 6 and the swing wheel 4 can also be arranged concentrically.

[0040] The track assembly 8 includes two Z-axis linear tracks 81, an X-axis linear track 82, and a slider 83. The two Z-axis linear tracks 81 are respectively installed on both sides of the corresponding mounting slot 11 on the fixed back plate 1. The two ends of the X-axis linear track 82 are slidably engaged with the two Z-axis linear tracks 81. The slider 83 is slidably mounted on the X-axis linear track 82. One end of the slider 83 is linked to the linkage shaft 6, and the other end is equipped with a clamping mechanism for gripping the product. The clamping mechanism is not shown in the figure, but it can adopt existing clamping structures such as suction cups or pneumatic clamps. The above track assembly structure is reliable and its operation is stable.

[0041] In addition, the front of the fixed back plate 1 has a perimeter 12 formed on three sides of its front edge, and a cover plate 9 is provided on the perimeter 12. The cover plate 9 can play the role of dust prevention and protection.

[0042] During operation, the power source drives the main shaft 2 to rotate, and the eccentric shaft 21 revolves relative to the center of the main shaft 2, which in turn drives the swing wheel 4 to revolve relative to the center of the main shaft 2. The swing wheel 4 then drives the support bearing 5 and its corresponding linkage shaft 6 to swing synchronously relative to the center of the eccentric shaft 21. However, at the same time, under the constraint of the support bearing 5 and the swing profile surface 71, the swing wheel 4 will rotate relative to the eccentric shaft 21 in the opposite direction to its revolution. Therefore, the swing speed of the support bearing 5 and its corresponding linkage shaft 6 on the swing wheel 4 is slower than the rotation speed of the main shaft 2. The speed difference between the two achieves the purpose of deceleration. Moreover, the swing trajectory of the linkage shaft 6 is consistent with that of the support bearing, moving along a C-shaped trajectory. The linkage shaft 6 then drives the slider 83 to move synchronously.

[0043] The beneficial effects of the embodiments of the present invention are:

[0044] 1. The support block is set inside the three support bearings. Compared with the cycloidal frame in the prior art, the outer curved surface is changed to the inner curved surface, making the structure more compact and reasonable and greatly reducing the volume.

[0045] 2. The existing rounded square trajectory is prone to bearing vibration at the rounded corners. It has now been changed to a C-shaped contour surface, which includes an arc segment and two straight segments, making the movement more continuous and smooth.

[0046] 3. The support bearing has a higher speed and greater torque when passing through straight sections, reducing the influence of gravity and making the operation smoother. The support bearing has a lower speed and faster speed when passing through circular arc sections, increasing the running speed and making the operation more rapid.

[0047] In the description of this invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0048] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0049] Please note to all technical personnel: Although the present invention has been described according to the specific embodiments above, the inventive concept of the present invention is not limited to this invention. Any modifications that utilize the inventive concept will be included within the scope of protection of this patent.

Claims

1. An inner curve type PPU robotic arm, comprising: Fixed backplate (1); The main shaft (2) is rotatably mounted on the fixed back plate (1), and its front end has an eccentric shaft (21) that is eccentrically positioned relative to the center of the main shaft (2). The power source (3) is installed on the back of the fixed back plate (1) and drives the connecting spindle (2). The swing wheel (4) is sleeved outside the eccentric shaft (21) and rotates with the eccentric shaft (21); Three support bearings (5) are evenly spaced around the center of the swing wheel (4); Linkage shaft (6), one end of which is rotatably connected to the swing wheel (4); The feature is that it also includes a support block (7), which is disposed on the inner side of the three support bearings (5). The outer side of the support block (7) forms a swing profile surface (71). The swing profile surface (71) includes two symmetrically arranged C-shaped profile surfaces. The C-shaped profile surface includes an arc segment (711) and straight segments (712) at both ends of the arc segment (711). The distance between the arc segment (711) and the rotation center of the main shaft (2) is greater than the distance between the straight segment (712) and the rotation center of the main shaft (2). When the swing wheel (4) moves, the three support bearings (5) and the swing profile surface (71) are always in contact to form a rolling fit, and the swing wheel (4) drives the linkage shaft (6) to move along the C-shaped trajectory.

2. The inner curve type PPU robotic arm according to claim 1, characterized in that: The rotation center of the linkage shaft (6), the rotation center of one of the supporting bearings (5), and the rotation center of the swing wheel (4) are all on the same straight line.

3. The inner curve type PPU robotic arm according to claim 2, characterized in that: The center distance between the linkage shaft (6) and the swing wheel (4) is greater than the center distance between the support bearing (5) and the swing wheel (4).

4. The inner curve type PPU robotic arm according to claim 1, characterized in that: The straight segment (712) is inclined inward.

5. The inner curve type PPU robotic arm according to claim 1, characterized in that: The fixed back plate (1) has a recessed mounting groove (11) on its front side, and the support block (7) and the swing wheel (4) are both located in the mounting groove (11).

6. The inner curve type PPU robotic arm according to claim 5, characterized in that: The support block (7) has a central hole (72) that matches the main shaft. The support block (7) is sleeved on the outside of the main shaft (2) and fixedly connected to the fixed back plate (1).

7. The inner curve type PPU robotic arm according to claim 5, characterized in that: It also includes a track assembly (8), which includes Two Z-axis linear rails (81) are respectively installed on both sides of the mounting slot (11) of the fixed back plate (1); The X-axis linear track (82) has two sliding connections at its two ends with two Z-axis linear tracks (81); The slider (83) is slidably set on the X-axis linear track (82) and is linked to the linkage shaft (6).

8. The inner curve type PPU robotic arm according to claim 5, characterized in that: The fixed back plate (1) has a rim (12) formed on the three sides of its front side, and a cover plate (9) is provided on the rim (12).

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