Bag gripping apparatus
By designing an aluminum alloy frame and a pneumatic actuator, the bag gripper is made lightweight and the clamping force is flexibly adjustable, solving the problems of heavy weight and non-adjustable clamping force of existing grippers, and improving the efficiency and safety of handling equipment.
Patent Information
- Application Number
- CN202521182769.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-11
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2035-06-11
AI Technical Summary
Existing bag grippers are made of heavy materials, which increases the load on the equipment, limits the speed and acceleration of movement, and makes it difficult to adjust the clamping force. This can easily lead to damage to bags or insecure gripping, affecting production safety and efficiency.
The design incorporates an aluminum alloy frame and pneumatic actuators, along with a buffer and adjustment device, to achieve lightweight gripper arms and flexible adjustment of gripping force, ensuring gripping stability and safety.
The weight of the gripper has been reduced, improving its movement flexibility and clamping adaptability, preventing damage to bags, ensuring stability during high-speed handling, and extending equipment life.
Smart Images
Figure CN223935744U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of transfer equipment technology, and in particular to a bag gripper. Background Technology
[0002] In automated production and warehousing logistics systems, grippers, as important end-effectors, are widely used in operations such as gripping, handling, and palletizing various materials. For handling bagged or packaged materials, such as rice, fertilizer, flour, and cement, which are packaged in flexible bags like woven or plastic bags, pneumatic grippers are widely used due to their simple structure, reliable operation, and ease of control.
[0003] However, to ensure sufficient structural strength to withstand the gripping force of heavy bags, many existing bag grippers are made of heavy materials such as steel, resulting in a large gripper weight. This not only increases the load on handling equipment such as robots, limiting their movement speed and acceleration, and reducing their effective payload capacity, but may also necessitate the use of larger, more expensive robots, affecting the overall economy and efficiency of the system. Furthermore, different types of bags vary greatly in weight, size, material (e.g., the roughness of woven bags, the smoothness of plastic bags), and the morphology of internal materials (e.g., the flowability of powder, the packing properties of granules). Traditional bag grippers often use fixed or inconveniently adjustable clamping forces. Excessive clamping force may cause bag breakage or damage to the internal materials; insufficient clamping force may result in a weak grip, causing slippage during high-speed handling, affecting production safety and stability. Utility Model Content
[0004] To address the aforementioned issues, this application provides a bag gripper that can quickly clamp and release.
[0005] To achieve the above objectives, the bag gripper designed in this application includes an aluminum alloy profile frame, a pneumatic actuator, and two gripper arms. The upper part of the aluminum alloy profile frame is provided with a connecting seat suitable for connecting an external drive mechanism. The two gripper arms are arranged at intervals opposite to each other along a first direction and are pivotally mounted on the bottom of the aluminum alloy profile frame. The pneumatic actuator is disposed on the aluminum alloy profile frame and configured to transmit the generated driving force to the gripper arms to drive the gripper arms to pivot relative to the aluminum alloy profile frame to open or close, thereby realizing the gripping or release of the bag. The aluminum alloy profile frame is also provided with a buffer, which is located on the path of the gripper arms pivoting to open, to limit the maximum opening angle of the gripper arms.
[0006] A further embodiment is that the aluminum alloy profile frame includes two parallel profile beams and two opposing base plates. The two base plates are respectively connected and fixed to both ends of the profile beams by fasteners, and the connecting seat is connected and fixed to the middle position of the profile beams by fasteners.
[0007] A further embodiment includes two first cylinders, a support is provided on the upper surface of the base plate, and the first cylinders are pivotally connected to the support; a pull rod is pivotally connected to the piston rod of the first cylinder, and the other end of the pull rod is connected and fixed to a rotating shaft extending in a second direction; a bearing seat adapted to the rotating shaft is provided on the lower surface of the base plate, and the gripper arm is connected and fixed to the rotating shaft; a clearance groove is provided on the base plate, the position of which is adapted to the position of the pull rod; wherein, the second direction is perpendicular to the first direction.
[0008] A further option is that the first cylinder is equipped with a speed regulating valve for adjusting its movement speed, and a pressure reducing valve is installed in the air circuit of the first cylinder.
[0009] A further embodiment is that the gripper arm includes a gripping hook seat and two swing arms arranged at intervals along the second direction. The proximal end of the swing arms is connected to the rotating shaft through a tightening sleeve. The gripping hook seat is connected and fixed to the distal end of the swing arms. The gripping hook seat is provided with a plurality of gripping hook fingers, which are arranged at equal intervals along the second direction on the gripping hook seat.
[0010] A further option is to have a baffle plate for contacting the bag fixed to the inner side of the hook seat.
[0011] A further option is that the buffer is an elastic buffer or a pneumatic buffer, which is fixedly mounted on the base plate by a bracket and located on the movement path of the swing arm.
[0012] A further embodiment is that the bottom of the aluminum alloy profile frame is also provided with a second cylinder extending vertically downwards, and a pressure plate is connected and fixed to the piston rod of the second cylinder.
[0013] The bag gripper designed in this application reduces the overall weight and moment of inertia of the gripper by constructing the main frame with aluminum alloy profiles, thereby reducing the load on external handling equipment. Simultaneously, by equipping the pneumatic system with a pressure regulating device to adjust the output force of the pneumatic actuator, the gripper arm's clamping force is easily adjustable. This allows the gripper to flexibly adapt to bags of different weights, sizes, materials, and internal material characteristics, avoiding damage to the bags or materials caused by excessive clamping force while ensuring sufficient clamping force for reliable gripping. Furthermore, the cylinder is equipped with a buffer mechanism, ensuring that the gripper arm can achieve smooth, low-impact opening and closing movements while meeting the requirements of rapid operation. This effectively reduces impact on the bags and vibration wear on the gripper itself and the handling equipment, helping to extend the equipment's service life and ensuring the stability of the material handling process. Attached Figure Description
[0014] Figure 1 This is a three-dimensional structural diagram of the bag gripper provided in the embodiments of this application.
[0015] Figure 2 yes Figure 1 Top view.
[0016] Figure 3 yes Figure 2 Sectional view at point AA.
[0017] Figure 4 This is a three-dimensional structural schematic diagram of the bag gripper provided in the embodiments of this application from another perspective.
[0018] The components include: aluminum alloy profile frame 10, profile beam 11, base plate 12, support 13, shaft seat 14, clearance slot 15, pneumatic actuator 20, first cylinder 21, pull rod 22, rotating shaft 23, gripper arm 30, hook seat 31, swing arm 32, expansion sleeve 33, hook finger 34, baffle plate 35, connecting seat 40, buffer 50, bracket 51, second cylinder 60, and pressure plate 61. Detailed Implementation
[0019] The preferred embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this application.
[0020] like Figures 1 to 4 As shown in the figure, the bag gripper described in this embodiment is mainly used for handling bagged materials, such as rice and fertilizer packaged in woven bags. The bag gripper mainly includes an aluminum alloy profile frame 10, a pneumatic actuator 20, two gripper arms 30, a connecting seat 40, and a buffer 50.
[0021] Specifically, the aluminum alloy profile frame 10 serves as the main support structure of the gripper, and is preferably made of lightweight, high-strength aluminum alloy profile, with a rectangular cross-sectional shape. The aluminum alloy profile frame 10 not only ensures the overall strength and rigidity of the gripper, but also significantly reduces the weight of the gripper itself, thereby reducing the load on the robot arm or other handling equipment subsequently connected to it.
[0022] A connecting seat 40 is fixedly installed on the upper part of the aluminum alloy profile frame 10. The connecting seat 40 can be a flange with bolt holes for easy fixed connection with an external drive mechanism, such as a connecting flange at the end of a robot arm, so as to realize quick assembly and disassembly of the gripper and the external drive mechanism.
[0023] The two gripper arms 30 are spaced apart and opposite to each other along a first direction, and are pivotally mounted on the bottom of the aluminum alloy profile frame 10. In this embodiment, the first direction is the length direction of the aluminum alloy profile frame 10, and the specific hinge structure can be a pin hinge to ensure that the gripper arms 30 can rotate flexibly around the hinge point.
[0024] The pneumatic actuator 20 is mounted on the aluminum alloy profile frame 10 and configured to transmit the generated driving force to the gripper arm 30, thereby driving the gripper arm 30 to pivot relative to the aluminum alloy profile frame 10 to open or close, thus realizing the gripping or release of the bag. In this embodiment, the pneumatic actuator 20 can be a cylinder, equipped with a solenoid valve for control, to achieve precise control and rapid response of the opening and closing action of the gripper arm 30. Simultaneously, to meet the gripping force requirements of different bags, a pressure reducing valve can also be installed in the pneumatic system to adjust the air supply pressure of the cylinder, thereby making the gripping force of the gripper arm 30 adjustable; and to achieve a smoother gripping action, a speed regulating valve can also be installed in the cylinder circuit to adjust the cylinder's movement speed and buffering performance.
[0025] A buffer 50 is also provided on the aluminum alloy profile frame 10. The buffer 50 is located on the path of the gripper arm 30 as it pivots to open, and is used to limit the maximum opening angle of the gripper arm 30. When the gripper arm 30 opens to the preset maximum angle, it will contact the buffer 50. Specifically, the buffer 50 can be an elastic buffer or a pneumatic buffer. Its main function is to provide cushioning when the gripper arm 30 reaches the maximum opening position, absorb kinetic energy, reduce impact, and accurately limit the maximum opening angle of the gripper arm 30. This design can effectively prevent the gripper arm 30 from over-opening due to excessive opening speed or inaccurate stroke control, avoiding possible mechanical interference, component collision damage, or affecting the starting position accuracy of subsequent gripping actions, thus ensuring the smoothness and safety of the gripper operation.
[0026] In some embodiments, such as Figure 1, Figure 2 As shown, the aluminum alloy profile frame 10 includes two parallel profile beams 11 and two opposing base plates 12. The two base plates 12 are respectively connected and fixed to both ends of the profile beams 11 by fasteners, and the connecting seat 40 is connected and fixed to the middle position of the profile beams 11 by fasteners. The two parallel profile beams 11 are fixed by the base plates 12 at both ends, forming an approximately rectangular closed frame structure. Compared with a single beam or other open structures, this design greatly improves the torsional stiffness and overall structural stability of the frame. At the same time, the base plates 12 provide a stable reference plane with well-defined dimensions, which facilitates the precise installation of pneumatic actuators 20 and other components on or between them.
[0027] In some embodiments, such as Figures 1 to 4 As shown, the pneumatic actuator 20 includes two first cylinders 21. A support 13 is provided on the upper surface of the base plate 12, and the first cylinders 21 are pivotally connected to the support 13. The piston rod of the first cylinder 21 is pivotally connected to a pull rod 22, and the other end of the pull rod 22 is connected and fixed to a rotating shaft 23 extending in a second direction. A bearing seat 14 adapted to the rotating shaft 23 is provided on the lower surface of the base plate 12, and the gripper arm 30 is connected and fixed to the rotating shaft 23. A clearance groove 15 is provided on the base plate 12, the position of which is adapted to the position of the pull rod 22. The second direction is perpendicular to the first direction. In this way, by using two independent first cylinders 21 to drive the gripper arms 30 on both sides respectively, and transmitting power through a similar linkage mechanism, i.e., the pull rod 22, a highly symmetrical driving force and precise synchronous movement can be achieved, which can effectively avoid bag tilting, unstable gripping, or even slippage caused by unilateral driving or asynchronous movement. In this embodiment, a speed regulating valve is adapted to the first cylinder 21 to adjust its speed; a pressure reducing valve is installed in the air passage of the first cylinder 21. Furthermore, as... Figure 1 , Figure 3 , Figure 4 As shown, the buffer 50 is fixedly mounted on the base plate 12 by the bracket 51 and is located on the movement path of the swing arm 32.
[0028] In some embodiments, such as Figure 1 , Figure 3 , Figure 4As shown, the gripper arm 30 includes a hook seat 31 and two swing arms 32 spaced apart along the second direction. The proximal end of the swing arms 32 is connected to the rotating shaft 23 via a tightening sleeve 33. The hook seat 31 is fixedly connected to the distal end of the swing arms 32. Multiple hook fingers 34 are provided on the hook seat 31, and these hook fingers 34 are equidistantly spaced along the second direction. The two spaced swing arms 32 and the hook seat 31 form a wider and more stable frame structure, greatly improving the overall bending and torsional stiffness of the gripper arm 30. During the gripping process, even if the bag is subjected to uneven force or moves, the gripper arm 30 is not prone to deformation or shaking, ensuring gripping stability. Furthermore, the spaced arrangement of the multiple hook fingers 34 better adapts to the soft and irregular surface shape of the bag, distributing the total gripping force across the multiple hook fingers 34, reducing local pressure at each contact point, and effectively preventing puncture, tearing, or excessive compression of the bag material due to concentrated pressure. In one specific example, the gripper finger 34 includes an angled threaded section and a straight section. The threaded section is threadedly fixed to the gripper seat 31, and the straight section extends obliquely upward in a first direction so as to naturally provide some support for the bag after the gripper arm 30 grips the bag.
[0029] In some embodiments, such as Figure 1 , Figure 3 As shown, a baffle plate 35 for contacting the bag is fixedly connected to the inner side of the gripper hook seat 31. In this embodiment, the inner side of the gripper hook seat 31 is the side facing the center of the gripper or the opposite gripper arm 30. The baffle plate 35 is usually a flat or slightly curved plate structure with a certain area. Its material can be metal, reinforced plastic or other wear-resistant materials. Its position design is such that when the gripper arm 30 closes and clamps the bag, this baffle plate 35 will make surface contact with the side or near the bottom of the area where the bag is clamped, so as to work in conjunction with multiple gripper hook fingers 34 to complete the stable fixation of the bag, effectively preventing the bag from accidentally slipping or rotating during high-speed handling or posture changes.
[0030] In some embodiments, such as Figure 3 , Figure 4As shown, the bottom of the aluminum alloy profile frame 10 is also provided with a vertically downward extending second cylinder 60, and a pressure plate 61 is connected and fixed to the piston rod of the second cylinder 60. The action of the second cylinder 60 is independently controlled by the control system. Its working process is usually as follows: after the gripper arm 30 successfully clamps and lifts the bag, the piston rod of the second cylinder 60 extends, driving the pressure plate 61 to move downward, applying a certain pressure to the top of the gripped bag. This pressure can be maintained during the handling process or before placement. During the handling process, especially during rapid movement or rotation, the downward pressure applied by the pressure plate 61 helps to stabilize the material on the top of the bag, reduce shaking, thereby enhancing the stability and safety of the entire handling process and reducing the risk of bag posture changes or instability caused by material shaking.
[0031] In the description of this application, it should be noted that the terms "vertical", "up", "down", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and 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 this application.
[0032] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set," "install," "connect," and "link" 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 application according to the specific circumstances.
[0033] Finally, it should be noted that the above descriptions are merely preferred embodiments of this application and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A bag gripper, characterized in that, The device includes an aluminum alloy profile frame, a pneumatic actuator, and two gripper arms. The upper part of the aluminum alloy profile frame is provided with a connecting seat suitable for connecting an external drive mechanism. The two gripper arms are spaced apart and opposite to each other along a first direction and are pivotally mounted on the bottom of the aluminum alloy profile frame. The pneumatic actuator is disposed on the aluminum alloy profile frame and configured to transmit the generated driving force to the gripper arms to drive the gripper arms to pivot relative to the aluminum alloy profile frame to open or close, thereby achieving the gripping or release of bags. A buffer is also provided on the aluminum alloy profile frame, located on the path of the gripper arms as they pivot to open, to limit the maximum opening angle of the gripper arms.
2. The bag gripper according to claim 1, characterized in that, The aluminum alloy profile frame includes two parallel profile beams and two opposing base plates. The two base plates are respectively connected and fixed to both ends of the profile beams by fasteners, and the connecting seat is connected and fixed to the middle position of the profile beams by fasteners.
3. The bag gripper according to claim 2, characterized in that, The pneumatic actuator includes two first cylinders. A support is provided on the upper surface of the base plate, and the first cylinders are pivotally connected to the support. A pull rod is pivotally connected to the piston rod of the first cylinder, and the other end of the pull rod is connected and fixed to a rotating shaft extending in a second direction. A bearing seat adapted to the rotating shaft is provided on the lower surface of the base plate, and the gripper arm is connected and fixed to the rotating shaft. A clearance groove is provided on the base plate, the position of which is adapted to the position of the pull rod. The second direction is perpendicular to the first direction.
4. The bag gripper according to claim 3, characterized in that, The first cylinder is equipped with a speed regulating valve for adjusting its movement speed, and a pressure reducing valve is provided in the air passage of the first cylinder.
5. The bag gripper according to claim 3, characterized in that, The gripper arm includes a gripping hook seat and two swing arms spaced apart along the second direction. The proximal end of the swing arms is connected to the rotating shaft via a tightening sleeve. The gripping hook seat is connected and fixed to the distal end of the swing arms. The gripping hook seat is provided with a plurality of gripping hook fingers, which are equidistantly spaced along the second direction on the gripping hook seat.
6. The bag gripper according to claim 5, characterized in that, The inner side of the hook base is connected and fixed with a baffle plate for contacting the bag.
7. The bag gripper according to claim 5, characterized in that, The buffer is an elastic buffer or a pneumatic buffer, which is fixedly mounted on the base plate by a bracket and located on the movement path of the swing arm.
8. The bag gripper according to any one of claims 1-7, characterized in that, The bottom of the aluminum alloy profile frame is also provided with a second cylinder that extends vertically downwards, and a pressure plate is connected and fixed to the piston rod of the second cylinder.