Gripping device and control method thereof

Abstract

The invention provides a grabbing device and a control method of the grabbing device.The grabbing device comprises a grabbing frame, a supporting part, a driving assembly and a controller, the supporting part is movably connected with the grabbing frame, the driving assembly is used for driving the supporting part to move relative to the grabbing frame, and the controller is in electric connection or signal connection with the driving assembly; the controller is used for driving the supporting part to move relative to the grabbing frame through the driving assembly. The grabbing device further comprises a control module, the control module is in electric connection or signal connection with the controller, the control module is used for controlling the controller to work or stop working, and the controller is further used for detecting the current value of the driving assembly and transmitting the detection result to the control module. The control module can convert the current value into a torque value, so that the torque value of the acting force applied to the to-be-grabbed workpiece by the supporting part driven by the driving assembly can be obtained, whether the supporting part completely abuts against the to-be-grabbed workpiece or not can be judged, and the reliability and safety in the grabbing process are improved.

Description

Technical Field

[0001] The present application relates to the technical field of gripping devices, and in particular to a gripping device and a control method for the gripping device. Background Art

[0002] During the vehicle production process, parts such as side panel assemblies are usually placed in direct feed frames. In order to reduce transportation costs, multiple samples of a part are usually placed in one frame. There may be differences in the placement of multiple samples, which may result in small position errors between multiple samples. When the grasping system grasps different samples, it is unable to accurately identify the position errors between different samples, which may easily cause shaking, scratching or damage to other samples during grasping. Summary of the invention

[0003] The present application provides a grasping device and a control method for the grasping device, so as to solve the technical problem in the prior art that the grasping device easily causes the grasped workpiece to shake during the grasping process.

[0004] In a first aspect, an embodiment of the present application provides a grasping device, comprising: a grasping frame; a supporting portion, the supporting portion being movably connected to the grasping frame; a driving component, the driving component being used to drive the supporting portion to move relative to the grasping frame; a controller, the controller being electrically or signal-connected to the driving component, the controller being used to drive the supporting portion to move relative to the grasping frame through the driving component; wherein the grasping device further comprises a control module, the control module being electrically or signal-connected to the controller, the control module being used to control the controller to work or stop working; the controller is also used to detect the current value of the driving component and transmit the detection result to the control module.

[0005] In this embodiment, by setting a controller in the grasping device, it can be used to detect the current value of the driving component in real time, and transmit the detection result to the control module. The control module can convert the detected current value into the real-time torque value of the driving component, that is, the control module can obtain the magnitude of the reaction force received by the driving component, and thus can obtain the magnitude of the force applied by the driving support part of the driving component to the workpiece to be grasped. At the same time, by comparing the obtained torque value with the preset value, it can be determined whether the support part is completely in contact with the workpiece to be grasped, thereby improving the reliability and safety of the grasping process and preventing the workpiece to be grasped from shaking during the grasping process and scratching other workpieces to be grasped.

[0006] In a specific embodiment, the driving assembly includes a motor and a driving member, the controller is electrically connected or signal-connected to the motor; and the driving member is fixedly connected to the supporting portion.

[0007] In a specific embodiment, the driving member includes a screw rod and a nut seat connected to each other, the screw rod is connected to the motor; and the supporting part is fixedly connected to the nut seat.

[0008] In a specific embodiment, the grasping device further includes a clamping mechanism, and one end of the screw rod is connected to the clamping mechanism.

[0009] In a specific embodiment, the clamping mechanism is a normally closed electromagnetic brake device.

[0010] In a specific embodiment, the grabbing frame has a receiving cavity, and the driving assembly and the clamping mechanism are located in the receiving cavity.

[0011] In a specific embodiment, the gripping device includes at least two support parts, the drive assembly, the controller and the clamping mechanism, and the support parts, the drive assembly, the controller and the clamping mechanism are symmetrically distributed along the height direction and / or length direction of the gripping device.

[0012] In a specific embodiment, the gripping device further comprises an integrated box, and the integrated box is provided with a hot-swap socket.

[0013] In a second aspect, an embodiment of the present application provides a control method for a gripping device, wherein the gripping device includes a support portion and a drive assembly, wherein the drive assembly includes a motor and a drive member; the control method for the gripping device includes:

[0014] Detecting the current value of the motor;

[0015] Obtaining a torque value according to the detected current value;

[0016] When the torque value is not equal to the preset torque value, the driving assembly drives the supporting portion to move toward the workpiece to be grasped;

[0017] When the torque value is equal to the preset torque value, the driving assembly stops driving the supporting part to move.

[0018] In this embodiment, through the control method of the above-mentioned grasping device, the offset between different workpieces to be grasped can be identified, so that when the grasping device grasps different workpieces to be grasped, the support part can completely abut against the workpiece to be grasped, thereby fixing the workpiece to be grasped and improving the reliability and safety of the grasping process.

[0019] In a specific embodiment, the grasping device further includes a clamping mechanism, and the control method of the grasping device further includes:

[0020] When the torque value is not equal to the preset torque value, controlling the clamping mechanism to separate from the driving member;

[0021] When the torque value is equal to the preset torque value, the clamping mechanism is controlled to clamp the driving member. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 A schematic diagram of the structure of a grabbing device provided in the present application in a specific embodiment;

[0024] Figure 2 This is a schematic structural diagram of a grabbing device provided in the present application in another specific embodiment;

[0025] Figure 3 for Figure 2 sectional view of;

[0026] Figure 4 A flow chart of a control method for a gripping device provided in the present application in a specific embodiment;

[0027] Figure 5 This is a flow chart of the control method of the gripping device provided in the present application in another specific embodiment.

[0028] Reference numerals:

[0029] 1- Grasping device;

[0030] 11-Grab the frame;

[0031] 111-accommodating chamber;

[0032] 12- supporting part;

[0033] 121-groove;

[0034] 13- driving assembly;

[0035] 131-motor;

[0036] 132-driving member;

[0037] 133-screw rod;

[0038] 134- nut seat;

[0039] 14- controller;

[0040] 15- clamping mechanism;

[0041] 16-Integrated box;

[0042] 161-Hot plug socket. DETAILED DESCRIPTION

[0043] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0044] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0045] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0046] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0047] During the production process of vehicles, parts such as side panel assemblies are usually placed in a direct feed frame, and a robot drives a gripping device to realize automatic gripping, thereby reducing labor costs and improving work efficiency. The gripping frame includes at least two support parts, which are used to engage with the workpiece to be gripped when gripping it, thereby fixing the workpiece to be gripped. In the actual production process, a plurality of workpieces to be gripped are usually placed in the direct feed frame, but due to the influence of production errors and placement positions, there may be a position error of about ±0.5mm between the multiple workpieces to be gripped. When the support part in the gripping device moves toward the workpiece to be gripped, it is impossible to identify the position error, which may easily lead to the support part and the workpiece to be gripped not being properly engaged. After the gripping device grips the workpiece to be gripped, the workpiece to be gripped shakes, affecting the safety of the gripping process, and easily scratching other workpieces to be gripped in the direct feed frame.

[0048] To solve the above technical problems, Figures 1 to 3As shown, an embodiment of the present application provides a grasping device 1 and a control method for the grasping device 1. The grasping device 1 includes: a grasping frame 11, a support portion 12, a driving component 13 and a controller 14, wherein the support portion 12 is movably connected to the grasping frame 11, the driving component 13 is used to drive the support portion 12 to move relative to the grasping frame 11, the controller 14 is electrically connected or signal-connected to the driving component 13, and the controller 14 is used to drive the support portion 12 to move relative to the grasping frame 11 through the driving component 13. Among them, the grasping device 1 also includes a control module, which is electrically connected or signal-connected to the controller 14, and the control module is used to control the controller 14 to work or stop working. The controller 14 can also be used to detect the current value of the driving component 13 and transmit the detection result to the control module.

[0049] In this embodiment, by setting a controller 14 in the grasping device 1, it can be used to detect the current value of the driving component 13 in real time, and transmit the detection result to the control module. The control module can convert the detected current value into the real-time torque value of the driving component 13, that is, the control module can obtain the magnitude of the reaction force exerted on the driving component 13, so as to obtain the magnitude of the force applied by the driving component 13 to drive the support part 12 to the workpiece to be grasped. At the same time, by comparing the obtained torque value with the preset value, it can be determined whether the support part 12 is completely in contact with the workpiece to be grasped, thereby improving the reliability and safety of the grasping process and preventing the workpiece to be grasped from shaking during the grasping process and scratching other workpieces to be grasped.

[0050] In the above embodiment, Figure 2 As shown, a groove 121 can be provided on the support portion 12. When the support portion 12 is fixedly connected to the workpiece to be grasped, the groove 121 is engaged with the workpiece to be grasped, which can improve the reliability and stability of the engagement and further improve the fixing effect of the support portion 12 and the workpiece to be grasped.

[0051] In a specific embodiment, Figures 1 to 3 As shown, the driving assembly 13 may include a motor 131 and a driving member 132 , the controller 14 is electrically connected or signal-connected to the motor 131 , and the driving member 132 is fixedly connected to the support portion 12 .

[0052] In this embodiment, the motor 131 is electrically connected to the driving member 132, so that the motor 131 is used to provide driving force to the driving member 132. At the same time, the controller 14 is electrically connected or signal-connected to the motor 131, so that the controller 14 can control the motor 131 to work or stop working, and the controller 14 can detect the current value of the motor 131 in real time, so as to judge in real time whether the support part 12 is completely fixed to the workpiece to be grasped according to the above description.

[0053] In the above embodiment, Figures 1 to 4As shown, the control method of the gripping device 1 may include but is not limited to the following steps:

[0054] S11: Detect the current value of the motor 131;

[0055] S12: Obtaining the torque value according to the detected current value;

[0056] S13: When the torque value is not equal to the preset torque value, the driving assembly 13 drives the supporting portion 12 to move toward the workpiece to be grasped;

[0057] S14: When the torque value is equal to the preset torque value, the driving assembly 13 stops driving the supporting part 12 to move.

[0058] In this embodiment, through the control method of the above-mentioned grasping device 1, the offset between different workpieces to be grasped can be identified, so that when the grasping device 1 grasps different workpieces to be grasped, the support part 12 can completely abut against the workpiece to be grasped, thereby fixing the workpiece to be grasped and improving the reliability and safety of the grasping process.

[0059] In the above embodiment, Figure 2 and Figure 3 As shown, the driving member 132 may include a screw rod 133 and a nut seat 134 connected to each other, the screw rod 133 is connected to the motor 131 , and the support portion 12 is fixedly connected to the nut seat 134 .

[0060] In this embodiment, the driving member 132 can be a ball screw structure, and the screw rod 133 is connected to the motor 131, so that the motor 131 can drive the screw rod 133 to rotate axially when working, thereby driving the nut seat 134 to move along the extension direction of the screw rod 133. At the same time, since the support part 12 is fixedly connected to the nut seat 134, the motor 131 can drive the support part 12 to move through the ball screw structure composed of the screw rod 133 and the nut seat 134 when working.

[0061] When the motor 131 is working, it can also change the direction of rotation of the screw rod 133 to change the direction of movement of the nut seat 134, so as to control the support part 12 to move toward or away from the workpiece to be grasped, so as to adjust the position of the support part 12 relative to the workpiece to be grasped.

[0062] In the present application, the electromagnetic power of the motor 131 can be calculated by the voltage value and the current value of the motor 131, and then the rotor angular velocity of the motor 131 is calculated according to the rated parameters of the motor 131 and the actual motor 131 speed, so that the electromagnetic torque and the inertia torque of the motor 131 can be calculated, and then the relationship between the torque value and the current can be calculated by the torque equation of the motor 131. In the embodiment of the present application, the relationship between the current value and the torque value can be shown as formula (1):

[0063]

[0064] Among them, F is the torque value, I is the current value, and hp is the screw pitch. The torque value can be calculated by formula (1) after the controller 14 detects the current value of the motor 131, thereby calculating the force applied by the support part 12 to the workpiece to be grasped, and then judging whether the support part 12 is engaged with the workpiece to be grasped, so as to improve the safety and reliability of the grasping process.

[0065] In a specific embodiment, Figure 2 and Figure 3 As shown, the grasping device 1 may further include a clamping mechanism 15 , and one end of the screw rod 133 is connected to the clamping mechanism 15 .

[0066] In this embodiment, when the control module detects that the torque value obtained after the current value of the motor 131 is converted to be equal to the preset torque value, the control module controls the motor 131 to stop working through the controller 14, so that the motor 131 stops driving the screw rod 133 to rotate, so that the screw rod 133 stops driving the support part 12 to continue to move through the nut seat 134. At the same time, the grasping device 1 also includes a clamping mechanism 15, so that one end of the screw rod 133 is connected to the clamping mechanism 15. When the control module controls the motor 131 to stop working through the controller 14, the clamping mechanism 15 can be switched to a braking state, and the end of the screw rod 133 away from the motor 131 is clamped, so as to further enhance the braking effect on the screw rod 133, and prevent the screw rod 133 from continuing to drive the support part 12 to continue to move toward the workpiece to be grasped due to inertia, resulting in damage to the workpiece to be grasped.

[0067] In the above embodiment, the clamping mechanism 15 can be a normally closed electromagnetic brake device, which can include components such as a rotor, a stator, a friction plate, and a spring. One end of the screw rod 133 extends into the mounting hole of the rotor. When the clamping mechanism 15 is in a relaxed state, the coil of the stator is energized, and the electromagnetic force generated causes the friction force to move away from the rotor and compress the spring, so that the rotor can rotate, thereby allowing the screw rod 133 to rotate freely. When the clamping mechanism is in a braking state, the coil of the stator is de-energized and stops generating electromagnetic force. The friction plate clamps and fixes the rotor under the action of the spring rebound force, thereby limiting the rotation of the screw rod 133 fixedly connected to the rotor mounting hole, thereby achieving a braking effect on the screw rod 133.

[0068] In this embodiment, the clamping mechanism 15 is a normally closed electromagnetic brake device, which has the advantages of compact structure, simple operation, high reliability and long service life. The normally closed electromagnetic brake device is sensitive to response, and can enable the clamping mechanism 15 to quickly brake the screw rod 133 in a short time. At the same time, the normally closed electromagnetic brake device is in a braking state when the power is off, and in a relaxed state when the power is on. Therefore, when the control module needs to brake the screw rod 133, it can synchronously control the motor and the clamping mechanism to be in a power-off state, thereby simplifying the operation steps, improving the overall state consistency of the grasping device 1, and improving the braking effect on the screw rod 133.

[0069] In the above embodiment, Figure 2 , Figure 3 and Figure 5 As shown, the above step S13 may further specifically include:

[0070] S131; when the torque value is not equal to the preset torque value, the clamping mechanism 15 is controlled to separate from the driving member 132, and the driving assembly 13 drives the support portion 12 to move toward the workpiece to be grasped;

[0071] The above step S14 may further specifically include:

[0072] S141: When the torque value is equal to the preset torque value, the clamping mechanism 15 is controlled to clamp the driving member 132, and the driving assembly 13 stops driving the supporting part 12 to move.

[0073] In this embodiment, by setting the clamping mechanism 15, when the torque value is equal to the preset torque value, that is, when the groove 121 of the support part 12 is engaged with the workpiece to be grasped, the clamping mechanism can quickly switch to the braking state, clamp the screw rod 133 in the driving member 132, and restrict its continued movement, so that the support part 12 can be quickly fixed at the current position to prevent the support part 12 from continuing to move toward the workpiece to be grasped and causing damage to the workpiece to be grasped. And when the torque value is not equal to the preset torque value, that is, when the groove 121 of the support part 12 is not fully engaged with the workpiece to be grasped, the clamping mechanism 15 can always be in a relaxed state and separated from the screw rod 133 to avoid affecting the normal operation of the driving member 132.

[0074] In the above-mentioned embodiments, by setting up a control module, it is possible to automatically receive the current value of the motor 131 detected by the controller 14, and convert it into the torque value of the force applied by the support part 12 to the workpiece to be grasped, thereby automatically judging whether the groove 121 on the support part 12 and the workpiece to be grasped are snapped into place, that is, through the relationship between the current value and the torque value, a force feedback system is formed, which enables the control module to detect in real time whether the support part 12 and the workpiece to be grasped are snapped into place, so that the grasping device 1 in this embodiment can automatically identify the position error between different workpieces to be grasped under the control of the control module, while improving the grasping effect, it can also realize automatic operation and improve the grasping efficiency.

[0075] By setting the grasping device 1 in the embodiment of the present application to perform grasping work, the manual operation process of at least 8 operators can be reduced, the working time is significantly shortened, and unmanned production and supervision of the entire process can be achieved. In addition, the grasping device 1 can identify at least 16 different workpieces to be grasped and perform grasping work, realizing a one-to-many working mode, without the need to set up multiple grasping devices corresponding to different workpieces to be grasped, and significantly reducing costs.

[0076] In a specific embodiment, Figure 2 and Figure 3 As shown, the gripping frame 11 may have a receiving cavity 111 , and the driving assembly 13 and the clamping mechanism 15 are located in the receiving cavity 111 .

[0077] In this embodiment, the grab frame 11 has a receiving cavity 111, which can reduce the weight of the grab frame 11 and reduce the cost, and can also be used to accommodate components such as the drive assembly 13 and the clamping mechanism 15, so as to reduce the overall space occupied by the grab device 1, further avoid the phenomenon that the grab device 1 collides with the workpiece to be grabbed during the grabbing process, and can protect the drive assembly 13 and the clamping mechanism 15. At the same time, accommodating components such as the drive assembly 13 and the clamping mechanism 15 in the receiving cavity 111 of the grab frame 11 can also ensure the rigidity and strength of the grab frame 11, improve the reliability and stability of the grab frame 11, and extend the service life of the grab frame 11.

[0078] In a specific embodiment, Figure 2 and Figure 3 As shown, the gripping device 1 may include at least two support parts 12, a drive assembly 13, a controller 14 and a clamping mechanism 15. The at least two support parts 12, the drive assembly 13, the controller 14 and the clamping mechanism 15 may be symmetrically distributed along the height direction and / or the length direction of the gripping device 1.

[0079] In this embodiment, the grasping device 1 includes at least two supporting parts 12, a driving assembly 13, a controller 14 and a clamping mechanism 15 symmetrically distributed along the height direction and / or length direction of the grasping device 1, so that the grasping device 1 can grasp and fix the workpiece to be grasped to avoid shaking of the workpiece to be grasped during the grasping process. The above-mentioned components are symmetrically distributed, which can reduce the number of molds required for component manufacturing, simplify the structure of the grasping device 1, and reduce assembly difficulty and production costs.

[0080] In a specific embodiment, Figure 1 As shown, the gripping device 1 may also be provided with an integrated box 16 , and the integrated box 16 may be provided with a hot-swap socket 161 .

[0081] In this embodiment, by providing an integrated box 16 on the gripping device 1, it can be used to place and protect components such as wires, power supplies, junction boxes, and circuit breakers. In addition, a hot-swap socket 161 is provided on the integrated box 16, so that various functional parts can be quickly installed or switched, so that the gripping device 1 can also have functions such as gluing and repair welding.

[0082] The gripping device 1 provided in the present application can be used to grip a variety of different workpieces to be gripped. When gripping different workpieces to be gripped, the control module can control the motor 131 to be within a larger power range through the controller 14, so that the support part 12 can quickly approach the workpiece to be gripped within the range of ±1mm under the drive of the drive component 13, while achieving coarse positioning while avoiding the coarse positioning time being too long to affect the gripping efficiency. Then, the gripping device 1 is controlled to perform fine positioning according to the control method of the gripping device 1 mentioned above, so that the support part 12 of the gripping device 1 is snapped into place with the workpiece to be gripped, and during the fine positioning process, the motor 131 is kept within a smaller power range, and the fine positioning time is extended to improve the accuracy of fine positioning, so that the gripping device 1 can completely grip and fix the workpiece to be gripped.

[0083] In the above embodiments, the gripping device 1 may also adopt an OPENcan bus, which can improve the integration of the control module and increase the control points compared to a point-to-point signal line, thereby improving the control effect of the control module.

[0084] In the above embodiments, the control module may also be provided with a router, so that when the components in the grasping device 1 are connected through signals, the control module can control the opening or closing of each component through a wireless network through the router, thereby improving the efficiency and accuracy of the control process.

[0085] In the above embodiments, a teaching pendant may be provided in the grasping device 1 so as to monitor the control process of the control module. At the same time, the grasping device 1 in the embodiment of the present application can reduce the number of proximity switches used by providing a force feedback system compared to the grasping device in the related art, thereby reducing costs and simplifying the structure.

[0086] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A gripping device, characterized in that: The grabbing device comprises: Grab the frame; A support portion, the support portion being movably connected to the grabbing frame; a drive assembly, the drive assembly being used to drive the support portion to move relative to the grab frame; a controller, the controller being electrically or signal-connected to the drive assembly, the controller being used to drive the support portion to move relative to the grab frame through the drive assembly; Wherein, the grasping device also includes a control module, which is electrically or signal-connected to the controller, and is used to control the controller to work or stop working; the controller is also used to detect the current value of the driving component and transmit the detection result to the control module.

2. The gripping device according to claim 1, characterized in that: The driving assembly includes a motor and a driving member, and the controller is electrically connected or signal-connected to the motor; The driving member is fixedly connected to the supporting portion.

3. The gripping device according to claim 2, characterized in that: The driving member comprises a screw rod and a nut seat connected to each other, and the screw rod is connected to the motor; The supporting portion is fixedly connected to the nut seat.

4. The gripping device according to claim 3, characterized in that: The grasping device also includes a clamping mechanism, and one end of the screw rod is connected to the clamping mechanism.

5. The gripping device according to claim 4, characterized in that: The clamping mechanism is a normally closed electromagnetic brake device.

6. The gripping device according to claim 4, characterized in that: The grabbing frame has a receiving cavity, and the driving assembly and the clamping mechanism are located in the receiving cavity.

7. The gripping device according to claim 4, characterized in that: The gripping device comprises at least two supporting parts, the driving assembly, the controller and the clamping mechanism, and the supporting parts, the driving assembly, the controller and the clamping mechanism are symmetrically distributed along the height direction and / or length direction of the gripping device.

8. The gripping device according to any one of claims 1 to 7, characterized in that: The grabbing device also has an integrated box, and a hot-swap socket is arranged on the integrated box.

9. A method for controlling a gripping device, characterized in that: The gripping device comprises a supporting portion and a driving assembly, wherein the driving assembly comprises a motor and a driving member; The control method of the gripping device comprises: Detecting the current value of the motor; Obtaining a torque value according to the detected current value; When the torque value is not equal to the preset torque value, the driving assembly drives the supporting portion to move toward the workpiece to be grasped; When the torque value is equal to the preset torque value, the driving assembly stops driving the supporting part to move.

10. The control method of the gripping device according to claim 9, characterized in that: The grasping device further includes a clamping mechanism, and the control method of the grasping device further includes: When the torque value is not equal to the preset torque value, controlling the clamping mechanism to separate from the driving member; When the torque value is equal to the preset torque value, the clamping mechanism is controlled to clamp the driving member.

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