A mechanical gripper for thickness detection of lithium battery cores after hot pressing.

Abstract

This utility model discloses a mechanical gripper for thickness detection of lithium battery cores after hot pressing. It includes a mounting base, a clamping assembly, a driving assembly, and a rangefinder. The clamping assembly, driving assembly, and rangefinder are all mounted on the mounting base, which has a mounting plate with holes. The clamping assembly includes opposing grippers and pressure plates respectively positioned above the grippers. The driving assembly includes a pitch-changing cylinder and a clamping cylinder. The pitch-changing cylinder is connected to the grippers, and the output end of the clamping cylinder is connected to the pressure plates. The rangefinder is positioned above the mounting base, with its laser axis perpendicularly pointing to the gripper support. The distances between the rangefinder and the gripper reference plane and the upper surface of the core are measured, thereby calculating the core thickness. This structure can be directly placed at an intermediate station after the lithium battery core hot pressing process and before the welding process, enabling online measurement and screening of core thickness.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, and in particular to a mechanical gripper for detecting the thickness of lithium battery cores after hot pressing. Background Technology

[0002] The lithium battery core is one of the core structural components of a lithium-ion battery. Especially in the production process of square aluminum-cased batteries, after the core is wound, it needs to undergo hot pressing to compact the interlayer structure and reduce its thickness, thereby meeting the dimensional requirements of subsequent casing processes. Typically, hot pressing equipment compresses and shapes the core within a specified time by setting temperature and pressure parameters to achieve the required thickness standard.

[0003] However, in actual production, the hot-pressing effect is often affected by various factors, such as equipment aging, hot-pressing temperature fluctuations, or insufficient pressure control precision. These factors can all lead to unstable core thickness after hot pressing, especially springback after hot pressing, causing the core thickness to exceed the process range. If the core proceeds to subsequent shelling or welding processes without effective testing, it may cause assembly difficulties, abnormal electrical performance, or even scrap the entire batch of products.

[0004] In existing technologies, a common approach is to use a pressure feedback system integrated into the hot-pressing equipment to detect the real-time compression state of the core during the hot-pressing process, using this as a basis for thickness judgment. However, this method can only monitor the state during compression and cannot reflect the actual rebound thickness of the core after cooling, making it difficult to prevent substandard cores from flowing into subsequent stages. Another approach is to manually sample and inspect the core thickness or perform a full inspection after hot pressing, but this method has low detection efficiency, relies on human judgment, and is difficult to maintain consistency and stability in the long term. Furthermore, manual inspection cannot be integrated into automated production line processes, leading to a contradiction between the detection rate and production line cycle time. Utility Model Content

[0005] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a mechanical gripper for thickness detection after hot pressing of lithium battery cores. The gripper can perform non-contact detection of the actual thickness of the core after hot pressing and before entering the subsequent process, accurately identify the thickness exceeding the limit caused by springback, thereby realizing online automatic screening and preventing unqualified cores from entering the subsequent shelling or welding process.

[0006] The technical solution adopted by this utility model to solve its technical problem is: a mechanical gripper for thickness detection after hot pressing of lithium battery cores, including a mounting base, a clamping assembly, a driving assembly, and a rangefinder. The clamping assembly, the driving assembly, and the rangefinder are all disposed on the mounting base, which is provided with a mounting plate and holes. The clamping assembly includes grippers arranged opposite each other and pressure plates respectively disposed above the grippers. The driving assembly includes a pitch-changing cylinder and a clamping cylinder. The pitch-changing cylinder is connected to the grippers, and the output end of the clamping cylinder is connected to the pressure plates respectively.

[0007] Furthermore, the gripper has two opposing jaws arranged in an L-shape, each including a vertical section and a horizontally extending support section, with the pressure plate positioned directly above the horizontally extending support section.

[0008] Furthermore, the mounting base is provided with a connecting plate and a guide rail, and the gripper is connected to the output end of the variable pitch cylinder through the connecting plate. The connecting plate is provided with a sliding engagement part that cooperates with the guide rail.

[0009] Furthermore, the rangefinder is positioned above the mounting plate and in the area above the hole, and an unobstructed measurement path is provided between the rangefinder and the clamping assembly for the rangefinder beam to pass through.

[0010] Furthermore, the rangefinder is a laser rangefinder.

[0011] Furthermore, the variable pitch cylinder and the clamping cylinder are double-acting cylinders.

[0012] The beneficial effects of this utility model are:

[0013] (1) This utility model can detect the thickness after the core is hot-pressed and after the cooling and springback occurs, overcoming the defect of the prior art that can only detect the thickness during the hot-pressing process and cannot identify the actual springback thickness.

[0014] (2) This utility model obtains the true thickness of the core after hot pressing through a non-contact measurement method, avoiding the problems of low measurement efficiency and unstable accuracy of traditional manual measurement methods.

[0015] (3) This utility model can instantly identify and sort cores with excessive thickness after hot pressing. It can be embedded in automated production line processes to prevent unqualified products from entering subsequent shelling or welding processes, effectively reducing the risk of scrapping the entire batch and improving product consistency. Attached Figure Description

[0016] Figure 1 This is a front perspective view of the mechanical gripper of this utility model.

[0017] Figure 2This is a bottom-view perspective view of the structure of the mechanical gripper of this utility model;

[0018] Figure 3 This is a schematic diagram of the connecting plate structure of this utility model;

[0019] In the figure, 1-mounting base; 11-guide rail; 12-connecting plate; 121-sliding mating part; 13-mounting plate; 131-hole; 2-clamp; 21-vertical section; 22-lateral support part; 3-pressure plate; 4-variable pitch cylinder; 5-clamping cylinder; 6-rangefinder. Detailed Implementation

[0020] The present invention will now be further described with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the present invention, and therefore only show the components relevant to the present invention.

[0021] like Figure 1 As shown, this utility model provides a mechanical gripper for detecting the thickness of lithium battery cores after hot pressing. It includes a mounting base 1, a clamping assembly, a driving assembly, and a rangefinder 6. The clamping assembly, the driving assembly, and the rangefinder 6 are all mounted on the mounting base 1.

[0022] The clamping assembly includes a pair of opposing grippers 2 and pressure plates 3 respectively disposed above the grippers 2. Each gripper 2 has an overall L-shaped structure, including a vertical section 21 and a horizontally extending support portion 22. The vertical section 21 is used for installation and fixation with the mounting base 1, and the horizontal support portion 22 is used to provide downward support for the lithium battery core during clamping. Each gripper 2 has a corresponding pressure plate 3 above it, which can cooperate with the horizontal support portion 22 of the gripper 2 to achieve upper and lower limit clamping of the core. To ensure the accuracy and effectiveness of the ranging process, in this embodiment, the horizontal support portion 22 is structurally extended so that it forms a complete planar reflection area at least in the area directly below the rangefinder 6, to ensure that the laser beam can directly irradiate and stably reflect on the vertical incident path, thereby improving the stability and repeatability of thickness measurement.

[0023] The driving assembly includes a variable-pitch cylinder 4 and two clamping cylinders 5. The variable-pitch cylinder 4 drives the gripper 2 to move left and right along the X-axis, thereby opening or closing the gripper 2. The clamping cylinders 5 drive the pressure plate 3 to move up and down along the Z-axis, thereby clamping or releasing the pressure plate 3. In this embodiment, there is only one variable-pitch cylinder 4, whose output end is connected to one side of the gripper 2. By driving this gripper 2 to move horizontally, the clamping action is achieved. The other side of the gripper 2 is a fixed end, which is installed through an intermediate connecting block. One end of the connecting block is threaded to the gripper 2, and the other end is installed on the mounting plate 13 by welding or screw connection, serving as a reaction support point during the clamping process and not participating in the sliding action.

[0024] like Figure 2 As shown, the mounting base 1 is provided with a mounting plate 13, a connecting plate 12, and a guide rail 11. The rangefinder 6 is mounted on top of the mounting base 1 and is fixedly connected to the upper support structure of the mounting base 1 by bolts. The mounting plate 13 has a hole 131, through which the ranging axis of the rangefinder 6 passes and points directly below the clamping area. In addition, the installation of the rangefinder 6 must be geometrically perpendicular to the upper surface of the transverse support part 22 of the gripper 2 to ensure that the laser optical axis can be perpendicularly directed towards the upper surface of the transverse support part 22 of the gripper 2.

[0025] like Figure 1 and Figure 2 As shown, the variable pitch cylinder 4 is mounted on the mounting plate 13. It can be fixed by bolts passing through the mounting plate 13 and connecting to the mounting base of the variable pitch cylinder 4. In practical applications, the variable pitch cylinder 4 can also be connected to the mounting plate 13 by using structures such as mounting flanges or positioning base plates, adapting to different layouts and available spaces. The gripper 2 is bolted to the connecting plate 12, and the connection method is a detachable structure, facilitating the replacement of the gripper 2 to adapt to size changes when switching between different sized core winding processes. The pressure plate 3 is connected to the output end of the clamping cylinder 5, which is fixed to the connecting plate 12 using conventional installation methods such as screws.

[0026] As shown in the figure Figure 1 , Figure 2 and Figure 3 As shown, the connecting plate 12 is also provided with a sliding engagement part 121, which cooperates with the guide rail 11 below the mounting base 1 to realize the guiding sliding of the gripper 2 in the X-axis direction. Specifically, the sliding engagement part 121 is preferably a slider structure integrally formed on the upper part of the connecting plate 12, and its overall shape is approximately a horizontally placed "H"-shaped component. The upper flange structure fits into the guide groove of the guide rail 11, so that the sliding engagement part 121 can achieve stable linear guidance in the guide rail 11. The guide rail 11 adopts a C-shaped profile structure, and its opening size matches the outer dimensions of the sliding engagement part 121, thereby ensuring good guiding accuracy and anti-sway capability during sliding. For the gripper 2 on the other side that is not connected to the variable pitch cylinder 4, there is no sliding engagement part 121. During assembly, the connecting plate 12 moves along the length direction (X-axis) of the guide rail 11 via the sliding fit part 121. The output end of the variable pitch cylinder 4 is welded or threaded to the connecting plate 12. The variable pitch cylinder 4 drives the output end to apply a thrust to the connecting plate 12. The connecting plate 12 connects to the gripper 2, thereby realizing the opening and closing action of the gripper 2. In another embodiment, a lubricating strip or a self-lubricating material can be provided between the sliding fit part 121 and the guide rail 11 to reduce frictional resistance and extend service life.

[0027] In the use of this utility model, the working process of the mechanical gripper mainly includes the following steps:

[0028] (1) Before starting the device, the rangefinder 6 is used to initially measure the reference plane in the clamping area. Specifically, the clamp 2 is driven to retract by the variable pitch cylinder 4, so that the lateral support part 22 of the clamp 2 is directly below the laser emission axis of the rangefinder 6, and the laser beam is perpendicularly irradiated on the upper surface of the lateral support part 22 of the clamp 2. The rangefinder 6 reads this reference distance as a reference value for subsequent measurements, that is, the vertical distance H1 from the rangefinder 6 to the upper surface of the lateral support part 22 of the clamp 2, which is used as a fixed reference input in the subsequent thickness calculation.

[0029] (2) When the lithium battery core is about to enter the clamping area, the control system issues a command to activate the variable pitch cylinder 4, causing the gripper 2 to open along the X-axis, reserving clamping space for the core to enter. Subsequently, the mounting base 1 drives the entire gripper 2 to the preset position. After the device is aligned, the variable pitch cylinder 4 activates again, driving the gripper 2 to retract and close inward, so that the lateral support part 22 of the gripper 2 lifts the core from below, achieving initial support for the core. During this stage, the clamping cylinder 5 does not activate, the pressure plate 3 is in the raised state, and the core falls on the support surface of the gripper 2 by its own weight, without being subjected to additional vertical clamping force.

[0030] (3) After the core is stably positioned, the rangefinder 6 activates the high-precision laser ranging function to obtain the actual distance H2 between the current upper surface of the core and the rangefinder 6. At the same time, the system calls the previously measured reference distance H1 (i.e., the vertical distance from the rangefinder 6 to the upper surface of the transverse support part 22 of the gripper 2). The formula for calculating the core thickness D is: D=H1-H2.

[0031] (4) After the thickness detection is completed and the measurement data is confirmed, the control system drives the clamping cylinder 5 to move, so that the pressure plate 3 moves downward along the Z-axis and, together with the transverse support part 22 of the gripper 2, applies a clamping force to the top of the core to achieve three-way stable limit clamping.

[0032] (5) The control system compares the core thickness D measured by laser with the preset process tolerance range to determine whether the core is qualified. The qualification judgment standard can be set according to the size specifications and quality standards of different lithium battery products, and has a certain degree of flexibility and adjustability. If the test result is within the allowable range, the system controls the mechanical gripper to perform normal unloading operation and accurately transfer the core to the target tray for transfer; if the thickness value exceeds the set upper and lower limits, the control system determines it as a non-conforming product and controls the gripper 2 to transfer it to the NG pull belt or abnormal recycling area to complete the defective screening and prevent non-conforming cores from entering subsequent processes such as shelling or welding.

[0033] Step 5: In practical applications, the motion control of the gripper's variable-pitch cylinder 4 and clamping cylinder 5 is usually uniformly scheduled by a host computer or the overall line control system. Alternatively, an independent programmable logic controller (PLC) unit can be set up to achieve autonomous unit control. Furthermore, to achieve structural migration of the mechanical gripper as a whole, a positioning base (not shown in detail in the figure) is provided on the back or top of the mounting base 1 for mounting a standard flange. This base has a standard interface for docking with the flanges of actuators of robotic arms or collaborative robots, thereby realizing the spatial movement of the mechanical gripper. This utility model structure can be directly arranged in the intermediate station after the lithium battery core hot pressing process and before the welding process, realizing online measurement and screening of the core thickness.

[0034] In another embodiment of this utility model, the variable pitch cylinder 4 can be configured as two, respectively installed on the left and right sides of the mounting plate 13, each connected to the connecting plate 12 through its output end. The connecting plate 12 is threadedly connected to the corresponding gripper 2, thereby driving the grippers 2 on both sides to perform symmetrical opening and closing movements along the X-axis. In this structural form, the grippers 2 on both sides form sliding components with the corresponding connecting plate 12 and sliding mating part 121, and respectively cooperate with the guide rail 11 located on the mounting base 1 to achieve bidirectional symmetrical sliding control.

[0035] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it. They should not be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be covered within the protection scope of this utility model.

Claims

1. A mechanical gripper for thickness detection of lithium battery cores after hot pressing, comprising a mounting base, a clamping assembly, a driving assembly, and a rangefinder, wherein the clamping assembly, the driving assembly, and the rangefinder are all disposed on the mounting base, characterized in that: The mounting base is provided with a mounting plate, and the mounting plate is provided with holes; the clamping assembly includes opposing grippers and pressure plates respectively disposed above the grippers; the driving assembly includes a pitch cylinder and a clamping cylinder, the pitch cylinder is connected to the grippers, and the output end of the clamping cylinder is connected to the pressure plates respectively.

2. The mechanical gripper for detecting the thickness of the lithium battery roll core after heat pressing according to claim 1, wherein: The grippers are arranged opposite each other and have an overall L-shaped structure. Each gripper includes a vertical section and a horizontal support section extending in the horizontal direction. The pressure plates are respectively arranged directly above the horizontal support sections.

3. The mechanical gripper for detecting the thickness of the lithium battery roll core after heat pressing according to claim 1, wherein: The mounting base is provided with a connecting plate and a guide rail. The gripper is connected to the output end of the variable pitch cylinder through the connecting plate. The connecting plate is provided with a sliding engagement part that cooperates with the guide rail.

4. The mechanical gripper for detecting the thickness of a lithium battery roll core after heat pressing according to claim 1, wherein: The rangefinder is positioned above the mounting plate and in the area above the hole. An unobstructed measurement path is provided between the rangefinder and the clamping assembly for the rangefinder beam to pass through.

5. The mechanical gripper for detecting the thickness of a lithium battery roll core after heat pressing according to claim 1, wherein: The rangefinder is a laser rangefinder.

6. The mechanical gripper for detecting the thickness of a lithium battery roll core after heat pressing according to claim 1, wherein: The variable pitch cylinder and the clamping cylinder are double-acting cylinders.

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