A hybrid variable cell palletizing robot mechanism

Abstract

This invention belongs to the field of palletizing robot technology. To address the low applicability of traditional palletizing robots, a hybrid variable-cell palletizing robot mechanism is provided, including a fixed base, a rotating base, a dual-branch hybrid motion chain, a variable-cell control component, and an end effector. The rotating base is rotatably mounted on top of the fixed base. The dual-branch hybrid motion chain connects the rotating base and the end effector, and includes a first branch, a second branch, and a passive kinetic pair forming a closed-loop motion chain. The variable-cell control component includes a locking device and a clutch. The locking device is located at the kinetic pair of the dual-branch hybrid motion chain, and the clutch is connected to the drive end of the second branch. By locking or unlocking the locking device and engaging or disengaging the clutch, the mechanism's degrees of freedom can be switched between two degrees of freedom and multiple single degrees of freedom. This mechanism can switch between two degrees of freedom and multiple single degrees of freedom, thereby meeting different palletizing task requirements.

Description

Technical Field

[0001] This invention belongs to the field of palletizing robot technology, and particularly relates to a hybrid variable cell palletizing robot mechanism. Background Technology

[0002] A palletizing robot is an industrial robot that automatically stacks individual items or packaged products onto pallets in a specific arrangement to form stable stacks for storage and transportation. Traditional palletizing robots mainly use serial mechanisms, which suffer from poor system rigidity and motion coupling, resulting in unsatisfactory performance under high-speed and heavy-load conditions. Parallel and hybrid mechanism palletizing robots can overcome the shortcomings of serial mechanisms in terms of system rigidity and motion coupling.

[0003] Currently, palletizing tasks in production lines can be divided into single-point repetitive tasks and multi-point flexible tasks. Variable cell mechanisms can achieve multifunctional and highly adaptable topological changes by changing the number of links and degrees of freedom. Therefore, applying them to the mechanism design of palletizing robots can create novel variable cell palletizing robot mechanisms that can achieve multiple configurations.

[0004] Currently available parallel or hybrid palletizing robots generally use a fully rotating joint configuration, or the driving joint is a prismatic joint and the passive joint is a rotating joint configuration. There are very few palletizing robots that use prismatic joints as passive kinematic joints (such as passive telescopic rods), making it difficult to apply them to different scenarios with complex trajectories such as variable diameter arcs and vertical line segments. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a highly adaptable hybrid variable cell palletizing robot mechanism.

[0006] This invention provides a hybrid variable cell palletizing robot mechanism, including a fixed base, a rotating base, a dual-branch hybrid motion chain, a variable cell control component, and an end effector;

[0007] The rotating base is rotatably mounted on the top of the fixed base. One end of the dual-branch hybrid kinematic chain is hinged to the rotating base, and the other end of the dual-branch hybrid kinematic chain is connected to the end effector. The dual-branch hybrid kinematic chain includes a first branch, a second branch, and a passive locating pair. The first branch and the second branch are connected through the passive locating pair to form a closed-loop kinematic chain.

[0008] The variable cell control component includes a locking device and a clutch. The locking device is located at the kinematic pair of the dual-branch hybrid kinematic chain, and the clutch is connected to the drive end of the second branch. The locking device engages with the clutch by locking or disengages from the clutch by unlocking the locking device, thereby enabling the switching of the mechanism's degrees of freedom between two degrees of freedom and multiple single degrees of freedom.

[0009] Optionally, the rotating base is connected to the top of the fixed base via a slewing bearing, and a first rotating motor is provided on the rotating base. The output shaft of the first rotating motor is connected to the slewing bearing, and the first rotating motor drives the rotating base to rotate around the vertical center line of the fixed base.

[0010] Optionally, the first branch includes a first active rod and a third connecting rod that are hinged in sequence. One end of the first active rod is hinged to the rotating base. A second rotating motor is provided at the hinge point between the first active rod and the rotating base. The second rotating motor drives the first active rod to rotate around the hinge point.

[0011] The second branch includes a second active rod, a fifth connecting rod, and a fourth connecting rod that are hinged in sequence. One end of the second active rod is hinged to the rotating base, one end of the fourth connecting rod is hinged to the rotating base, and both ends of the fifth connecting rod are respectively hinged to the other ends of the second active rod and the fourth connecting rod. The fifth connecting rod is connected to the third connecting rod through a passive sliding joint.

[0012] Optionally, the passive prismatic joint is a telescopic rod, one end of which is hinged to the end of the third link away from the first active link, and the other end of which is connected to the fifth link, so that the first branch, the second branch, and the telescopic rod together form a closed-loop kinematic chain of seven links, seven revolute joints, and one prismatic joint.

[0013] Optionally, the locking device includes a first locking member, a second locking member, and a third locking member. The first locking member is disposed at the hinge joint between the first active rod and the third connecting rod; the second locking member is disposed on the telescopic sleeve of the telescopic rod; and the third locking member is disposed at the connection joint between the fourth connecting rod and the fifth connecting rod. The first locking member, the second locking member, and the third locking member are all embedded clamping mechanisms, which can independently realize the locking or unlocking of the corresponding kinematic pairs.

[0014] Optionally, a third rotary motor is provided at the hinge point between the second active rod and the rotating base, and the clutch is located between the second active rod and the third rotary motor;

[0015] When the mechanism is in a two-degree-of-freedom mode, the clutch is engaged, and the third rotary motor drives the second drive rod to rotate; when the mechanism is in a single-degree-of-freedom mode, the clutch is disengaged, and the second drive rod moves passively with the closed-loop kinematic chain.

[0016] Optionally, the end effector is connected to the closed-loop kinematic chain via a sixth link. One end of the sixth link is connected to the telescopic rod, and the other end of the sixth link is provided with a quick-release interface. The end effector is detachably connected to the sixth link via the quick-release interface.

[0017] Optionally, the end effector is provided with a fourth rotary motor, the output axis of which is parallel to the output axis of the first rotary motor, and the fourth rotary motor drives the end effector to rotate around the central axis of the end effector to adjust the posture of the cargo.

[0018] Optionally, the single-degree-of-freedom mode includes three types: when the first locking member is locked, the mechanism forms a single-degree-of-freedom fixed-radius circular arc trajectory mode; when the second locking member is locked, the mechanism forms a single-degree-of-freedom variable-radius circular arc trajectory mode; when the third locking member is locked, the mechanism forms a single-degree-of-freedom vertical line segment trajectory mode.

[0019] The technical solution provided by the embodiments of the present invention has the following beneficial effects compared with the prior art:

[0020] This invention provides a hybrid variable-cell palletizing robot mechanism, which forms a hybrid closed-loop kinematic chain through a first branch, a second branch, and a passive prismatic joint, creating a stable structure of seven links, seven revolute joints, and one prismatic joint. The force transmission path of this closed-loop kinematic chain is short and symmetrical. Compared with a serial mechanism, this mechanism improves rigidity and makes it suitable for heavy-duty palletizing requirements. Compared with a pure revolute joint kinematic chain without passive prismatic joints, this mechanism can improve positioning accuracy by compensating for trajectory errors through the extension and retraction of the passive prismatic joints.

[0021] This mechanism incorporates a locking device and a clutch. The locking device can independently lock different kinematic pairs, and the clutch engages or disengages to switch between two degrees of freedom and various single degrees of freedom, thereby meeting the needs of different palletizing tasks. In single-point repetitive tasks, the mechanism can switch to the corresponding single-degree-of-freedom mode, while in multi-point flexible tasks, it can switch to two-degree-of-freedom mode. By utilizing the coordinated motion of the two degrees of freedom, it can achieve more complex and flexible palletizing trajectory planning, meeting diverse palletizing requirements. Attached Figure Description

[0022] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of a hybrid variable cell palletizing robot mechanism according to an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the kinematic chain of a hybrid variable-cell palletizing robot mechanism according to an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the clutch installation according to an embodiment of the present invention;

[0027] Figure 4 This is an exploded view of a hybrid variable-cell palletizing robot mechanism according to an embodiment of the present invention in a single-degree-of-freedom fixed-radius circular arc trajectory mode;

[0028] Figure 5 This is an exploded view of a hybrid variable-cell palletizing robot mechanism according to an embodiment of the present invention in a single-degree-of-freedom vertical line segment trajectory mode and a single-degree-of-freedom variable-radius circular arc trajectory mode.

[0029] The components include: 1. Fixed base; 2. Rotating base; 3. First rotating motor; 4. First drive rod; 5. Second rotating motor; 6. Third link; 7. First locking element; 8. Sixth link; 9. End effector; 10. Telescopic rod; 11. Second locking element; 12. Fifth link; 13. Third locking element; 14. Fourth link; 15. Second drive rod; 16. Third rotating motor; and 17. Clutch. Detailed Implementation

[0030] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0031] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

[0032] Reference Figure 1 As shown, this embodiment provides a hybrid variable cell palletizing robot mechanism, including a fixed base 1, a rotating base 2, a dual-branch hybrid motion chain, a variable cell control component, and an end effector 9.

[0033] The fixed base 1 is fixedly connected to the ground, and the rotating base 2 is rotatably mounted on the top of the fixed base 1 via a slewing bearing. The rotating base 2 is equipped with a first rotating motor 3, and the output shaft of the first rotating motor 3 is connected to the slewing bearing for transmission. The first rotating motor 3 drives the rotating base 2 to rotate around the vertical center line of the fixed base 1.

[0034] Reference Figure 2 As shown, one end of the dual-branch hybrid kinematic chain is hinged to the rotating base 2, and the other end is connected to the end effector 9. Specifically, the dual-branch hybrid kinematic chain includes a first branch, a second branch, and a passive prismatic joint. The first branch and the second branch are fixedly connected through the passive prismatic joint to form a closed-loop kinematic chain. The first branch includes a first driving rod 4 and a third connecting rod 6 that are hinged in sequence. One end of the first driving rod 4 is hinged to the rotating base 2, and the other end of the first driving rod 4 is connected to one end of the third connecting rod 6 through a revolute joint. A second rotary motor 5 is provided at the hinge point between the first driving rod 4 and the rotating base 2, and the second rotary motor 5 drives the first driving rod 4 to rotate around the hinge point. The second branch includes a second active rod 15, a fifth connecting rod 12, and a fourth connecting rod 14 that are hinged in sequence. One end of the second active rod 15 is hinged to the rotating base 2, one end of the fourth connecting rod 14 is hinged to the rotating base 2, and both ends of the fifth connecting rod 12 are hinged to the other ends of the second active rod 15 and the fourth connecting rod 14, respectively. The second active rod 15, the fifth connecting rod 12, the fourth connecting rod 14, and the rotating base 2 together form a parallelogram mechanism. The fifth connecting rod 12 is connected to the third connecting rod 6 through a passive sliding joint.

[0035] Continue to refer to Figure 1 and Figure 2 As shown, the passive prismatic joint is the telescopic rod 10. One end of the telescopic rod 10 is hinged to the end of the third link 6 away from the first active link 4, and the other end of the telescopic rod 10 is fixedly connected to the middle part of the fifth link 12, so that the first branch, the second branch and the telescopic rod 10 together form a closed-loop kinematic chain of seven links, seven revolute joints and one prismatic joint.

[0036] The variable cell control component includes a locking device and a clutch 17. The locking device is located at the kinematic pair of the double-branch hybrid kinematic chain, and the clutch 17 is connected to the drive end of the second branch. By locking the locking device and engaging with the clutch 17, or by unlocking the locking device and disengaging from the clutch 17, the mechanism's degrees of freedom can be switched between two degrees of freedom and multiple single degrees of freedom. In this embodiment, the mechanism includes four different motion modes. The driving relationship between the fixed base 1 and the rotating base 2 driven by the first rotating motor 3 remains unchanged in the four motion modes. However, the number and types of degrees of freedom of the closed-loop kinematic chain formed by the rotating base 2 and the first branch, the second branch and the telescopic rod 10 on its top will change with the change of motion mode.

[0037] Specifically, the four motion modes are: two-degree-of-freedom mode, single-degree-of-freedom fixed-radius circular arc trajectory mode, single-degree-of-freedom variable-radius circular arc trajectory mode, and single-degree-of-freedom vertical line segment trajectory mode. (Refer to...) Figure 3 As shown, a third rotary motor 16 is provided at the hinge point between the second drive rod 15 and the rotating base 2. A clutch 17 is provided between the second drive rod 15 and the third rotary motor 16. When the mechanism is in a two-degree-of-freedom mode, the clutch 17 is engaged, that is, the clutch 17 connects the second drive rod 15 and the third rotary motor 16, and the third rotary motor 16 drives the second drive rod 15 to rotate actively. When the mechanism is in a single-degree-of-freedom mode, the clutch 17 is disengaged, that is, the clutch 17 separates the second drive rod 15 from the third rotary motor 16, and the second drive rod 15 moves passively with the closed-loop kinematic chain.

[0038] Furthermore, the locking device includes a first locking element 7, a second locking element 11, and a third locking element 13. The first locking element 7 is located at the hinge between the first active rod 4 and the third connecting rod 6. The second locking element 11 is located on the telescopic sleeve of the telescopic rod 10. The third locking element 13 is located at the connection between the fourth connecting rod 14 and the fifth connecting rod 12. All three locking elements are embedded clamping mechanisms, capable of independently locking or unlocking their respective kinematic pairs. Specifically, when the mechanism is in a two-degree-of-freedom mode, the first locking element 7, the second locking element 11, and the third locking element 13 are all in the unlocked state. The closed-loop kinematic chain above the rotating base 2 is a two-loop two-degree-of-freedom closed-loop mechanism, including 7 rods, 7 revolute joints, and 1 prismatic joint. When it is necessary to lock the variable element to enter a single-degree-of-freedom mode, refer to... Figure 4 As shown, the first locking member 7 is embedded at the hinge between the first driving rod 4 and the third connecting rod 6, locking the revolute joint between the first driving rod 4 and the third connecting rod 6, thus restricting the relative rotation between the two connecting rods. At this time, the closed-loop kinematic chain above the rotating base 2 is a single-degree-of-freedom closed-loop mechanism with two loops, six rods, six revolute joints, and one prismatic joint, forming a single-degree-of-freedom fixed-radius circular arc trajectory pattern; refer to Figure 5 As shown, the second locking member 11 is embedded in the telescopic rod 10, which restricts the movement of the telescopic rod 10. At this time, the closed-loop kinematic chain above the rotating base 2 is a two-loop single-degree-of-freedom closed-loop mechanism, which includes 6 rods and 7 revolute joints, and the trajectory of the end of the mechanism is a variable radius arc. The mechanism forms a single-degree-of-freedom variable radius arc trajectory mode; refer to Figure 5As shown, the third locking member 13 is embedded in the hinge of the fourth link 14 and the fifth link 12, so that the rotating joint between the fourth link 14 and the fifth link 12 is locked, and the relative rotation between the two links is restricted. At this time, the closed-loop kinematic chain above the rotating base 2 is a single-loop four-bar three-rotating joint one-sliding joint single-degree-of-freedom closed-loop mechanism, which is in the form of a rocker-slider mechanism. The end trajectory is a vertical line segment, and the mechanism forms a single-degree-of-freedom vertical line segment trajectory pattern.

[0039] Reference Figure 1 As shown, the end effector 9 is connected to the closed-loop kinematic chain via the sixth link 8. One end of the sixth link 8 is connected to the telescopic rod 10, and the other end of the sixth link 8 is provided with a quick-release interface. The end effector 9 is detachably connected to the sixth link 8 via the quick-release interface, which facilitates the replacement of the end effector to adapt to different palletizing tasks. The end effector 9 is provided with a fourth rotary motor. The output axis of the fourth rotary motor is parallel to the output axis of the first rotary motor 3. The fourth rotary motor drives the end effector 9 to rotate around its own central axis to adjust the posture of the goods.

[0040] Among them, the vertical movement degree of freedom of the end effector 9 can be controlled independently by the second rotary motor 5 without relying on the cooperation of multiple branches, which reduces the complexity of the control algorithm. At the same time, the horizontal rotation of the rotating base 2 is driven independently by the first rotary motor 3, which forms a decoupled control with the lifting and arc movement of the end effector 9, reducing the cumulative error during the movement process.

[0041] The mechanism provided in this embodiment realizes the transformation from a two-degree-of-freedom mode to a single-degree-of-freedom mode with multiple different trajectories by locking the variable cell. The mechanism itself has a light load and a large working space, which can meet the needs of actual palletizing operations.

[0042] It should be noted that in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0043] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A hybrid variable-cell palletizing robot mechanism, characterized in that, Includes a fixed base (1), a rotating base (2), a dual-branch hybrid kinematic chain, a variable cell control assembly, and an end effector (9); The rotating base (2) is rotatably disposed on the top of the fixed base (1). One end of the dual-branch hybrid kinematic chain is hinged to the rotating base (2), and the other end of the dual-branch hybrid kinematic chain is connected to the end effector (9). The dual-branch hybrid kinematic chain includes a first branch, a second branch and a passive locating pair. The first branch and the second branch are connected through the passive locating pair to form a closed-loop kinematic chain. The first branch includes a first active rod (4) and a third connecting rod (6) that are hinged in sequence. One end of the first active rod (4) is hinged to the rotating base (2). A second rotating motor (5) is provided at the hinge point between the first active rod (4) and the rotating base (2). The second rotating motor (5) drives the first active rod (4) to rotate around the hinge point. The second branch includes a second active rod (15), a fifth connecting rod (12), and a fourth connecting rod (14) that are hinged in sequence. One end of the second active rod (15) is hinged to the rotating base (2), one end of the fourth connecting rod (14) is hinged to the rotating base (2), and both ends of the fifth connecting rod (12) are hinged to the other ends of the second active rod (15) and the fourth connecting rod (14), respectively. The fifth connecting rod (12) and the third connecting rod (6) are connected by a passive sliding joint. The passive gliding joint is a telescopic rod (10). One end of the telescopic rod (10) is hinged to the end of the third link (6) away from the first active link (4), and the other end of the telescopic rod (10) is connected to the fifth link (12), so that the first branch, the second branch and the telescopic rod (10) together form a closed loop kinematic chain of seven rods, seven rotating joints and one gliding joint. The variable cell control component includes a locking device and a clutch (17). The locking device is located at the kinematic pair of the dual-branch hybrid kinematic chain. The locking device includes a first locking member (7), a second locking member (11), and a third locking member (13). The first locking member (7) is located at the hinge of the first driving rod (4) and the third connecting rod (6). The second locking member (11) is located on the telescopic sleeve of the telescopic rod (10). The third locking member (13) is located at the connection between the fourth connecting rod (14) and the fifth connecting rod (12). The first locking member (7), the second locking member (11), and the third locking member (13) are all embedded clamping mechanisms that can independently lock or unlock the corresponding kinematic pair. The clutch (17) is connected to the drive end of the second branch. It engages with the clutch (17) through locking by the locking device or disengages from the clutch (17) through unlocking by the locking device, thereby realizing the switching of the mechanism's degree of freedom between two degrees of freedom and multiple single degrees of freedom. The single-degree-of-freedom mode includes three types: when the first locking member (7) is locked, the mechanism forms a single-degree-of-freedom fixed-radius arc trajectory mode; when the second locking member (11) is locked, the mechanism forms a single-degree-of-freedom variable-radius arc trajectory mode; when the third locking member (13) is locked, the mechanism forms a single-degree-of-freedom vertical line segment trajectory mode.

2. The hybrid variable-cell palletizing robot mechanism according to claim 1, characterized in that, The rotating base (2) is connected to the top of the fixed base (1) via a slewing bearing. A first rotating motor (3) is provided on the rotating base (2). The output shaft of the first rotating motor (3) is connected to the slewing bearing. The first rotating motor (3) drives the rotating base (2) to rotate around the vertical center line of the fixed base (1).

3. The hybrid variable-cell palletizing robot mechanism according to claim 1, characterized in that, A third rotating motor (16) is provided at the hinge point between the second active rod (15) and the rotating base (2), and the clutch (17) is provided between the second active rod (15) and the third rotating motor (16). When the mechanism is in a two-degree-of-freedom mode, the clutch (17) is engaged, and the third rotary motor (16) drives the second active rod (15) to rotate; when the mechanism is in a single-degree-of-freedom mode, the clutch (17) is disengaged, and the second active rod (15) moves passively with the closed-loop kinematic chain.

4. The hybrid variable-cell palletizing robot mechanism according to claim 1, characterized in that, The end effector (9) is connected to the closed-loop kinematic chain via the sixth link (8). One end of the sixth link (8) is connected to the telescopic rod (10), and the other end of the sixth link (8) is provided with a quick-release interface. The end effector (9) is detachably connected to the sixth link (8) via the quick-release interface.

5. The hybrid variable-cell palletizing robot mechanism according to claim 2, characterized in that, The end effector (9) is equipped with a fourth rotary motor. The output axis of the fourth rotary motor is parallel to the output axis of the first rotary motor (3). The fourth rotary motor drives the end effector (9) to rotate around the central axis of the end effector (9) to adjust the posture of the cargo.

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