Shutdown strip rewinding control method based on material strip roll welding

Abstract

The invention belongs to the technical field of cell tab rolling, and particularly relates to a shutdown tape rewinding control method based on tape roll welding, which comprises the following steps: S1, a control system sends a shutdown signal, so that a main traction shaft is linked with a tape to do uniformly decelerated motion; s2, in the speed reduction process, an anvil block is linked to fall through an air cylinder, so that the material belt is separated from the welding shaft, the ultrasonic generator stops working, and shutdown is completed; s3, controlling the material belt to reverse for a certain distance so as to enable the main traction shaft to reverse to a corresponding position; s4, the main traction shaft and the welding shaft are restarted to move, so that the main traction shaft is linked with the material belt to restart to move; s5, in the acceleration process, an anvil block is linked to ascend through an air cylinder so that the anvil block can make the material belt abut against the welding shaft, and when the real-time pressure detected by a pressure sensor reaches the target pressure, the ultrasonic generator is restarted to work so as to complete restarting; and S6, the material belt is linked and conveyed through a main traction shaft, and ultrasonic rolling is conducted on the material belt through a welding shaft.

Description

Technical Field

[0001] The invention belongs to the technical field of battery cell tab rolling, and in particular relates to a shutdown and rewinding control method based on strip rolling. Background Art

[0002] In the process of multi-layer tab welding of lithium batteries, ultrasonic roller welding technology is particularly important. It can not only effectively weld multi-layer tabs to ensure the electrical connectivity and structural integrity of the battery, but also ultrasonic welding does not involve the melting of metal. Therefore, the internal resistance after welding is small and the conductivity is good, which is suitable for power battery tab welding.

[0003] When using ultrasonic roller welding equipment, it is inevitable to stop the machine midway, which will cause the welding position to be cold welded or not welded. At this time, it is necessary to rewind the tape, but manual rewinding cannot accurately determine the position where the tape should be rewound, which will cause excessive repeated welding. Since the mechanism of the ultrasonic welder is to send ultrasonic energy to beat the tape, it will cause the welded tape to lose most of the ductility of the metal. Therefore, when the ultrasonic wave is started again, the speed of the tape is not up, and the energy will be concentratedly released to the repeated welding area at the start, which is easy to cause the tape in this area to be welded through or cracked, resulting in waste of the tape.

[0004] In view of this, it is necessary to improve the defects of the prior art to overcome the deficiencies in practical applications. Summary of the invention

[0005] Based on the above-mentioned shortcomings and deficiencies in the prior art, one of the objects of the present invention is to at least solve one or more of the above-mentioned problems in the prior art. In other words, one of the objects of the present invention is to provide a shutdown and rewinding control method based on strip roller welding that meets one or more of the above-mentioned needs.

[0006] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0007] The present invention provides a method for controlling a stop and rewinding of a strip based on strip roller welding, comprising the following steps:

[0008] S1, the control system sends a stop signal to make the main traction shaft and the material belt start to move at a uniform deceleration speed from the preset speed;

[0009] S2. During the deceleration process, the anvil is driven down by the cylinder to separate the material strip from the welding shaft, and the ultrasonic generator is stopped to complete the shutdown;

[0010] S3, by controlling the material belt to move back a certain distance, so that the main traction shaft is rewound to the corresponding position;

[0011] S4, restart the movement of the main traction shaft and the welding shaft, so that the main traction shaft and the material belt start to move again;

[0012] S5. During the acceleration process, the anvil is raised by the cylinder linkage so that the anvil abuts the material strip against the welding shaft. When the anvil pressure reaches the welding pressure, the ultrasonic generator is restarted to complete the restart;

[0013] S6. The material belt is linked to the main traction shaft to transport the material belt at a preset speed, and the material belt is ultrasonically rolled through the welding shaft.

[0014] As a preferred solution, the preset speed of the main traction shaft when linked with the material belt movement is 50-150 m / min, and the rotation speed of the welding shaft is greater than the rotation speed of the main traction shaft.

[0015] As a preferred solution, the main traction shaft and the welding shaft are equipped with absolute encoders.

[0016] As a preferred solution, the air pressure value when the cylinder links the anvil to move is 0.15-0.3 MPa.

[0017] As a preferred solution, the distance that the material belt retreats in step S3 is:

[0018] S=P1-P0+S0

[0019] Among them, S represents the distance that needs to be rewound; P0 represents the absolute encoder position of the main traction shaft when the anvil starts to fall during shutdown and the anvil pressure does not meet the standard; P1 represents the absolute encoder position of the main traction shaft after the shutdown; S0 represents the distance the main traction shaft travels until the material strip moves again until the welding shaft starts ultrasonic rolling.

[0020] As a preferred solution, in step S3, the welding axis movement is restarted to uniformly accelerate the material strip by a distance of:

[0021] (When V2+at1≤V1);

[0022] (When V2+at1>V1);

[0023] Among them, V1 represents the preset speed of the material belt movement; a represents the acceleration set when the material belt starts; V2 represents the set speed of the material belt when the anvil starts to rise, and V2<V1; t1 represents the time required for the anvil to start to rise to the target pressure value.

[0024] As a preferred solution, when the real-time pressure value detected by the pressure sensor reaches the target pressure value, the ultrasonic generator is restarted; when the real-time pressure value detected by the pressure sensor is less than 98% of the target pressure value, the ultrasonic generator is stopped.

[0025] As a preferred solution, the material strip is configured as any one of copper foil, aluminum foil or composite foil.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention provides a shutdown and rewinding control method based on material strip roller welding. By rewinding the material strip a certain distance, the rewinding distance and position are accurately determined, which can effectively ensure the normal welding of the material strip when restarting after shutdown, avoid over-welding or welding through when the material strip is repeatedly welded, and improve the welding quality of the material strip. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of 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, drawings of other embodiments can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 1 is a flow chart of a method for controlling a stop and rewinding process based on strip roller welding according to an embodiment of the present invention;

[0030] Figure 2 1 is a schematic structural diagram of a stop and rewind control system based on strip roller welding according to an embodiment of the present invention;

[0031] In the figure: 1 welding shaft, 2 anvil, 3 main traction shaft, 4 material belt. DETAILED DESCRIPTION

[0032] In order to more clearly illustrate the embodiments of the present application, the specific implementation methods of the present application will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0033] In the description of the embodiments of the present application, the terms "upper", "lower", "front", "rear", etc., are based on the directions or positions shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present application. In addition, the terms "first", "second", etc. are only used to distinguish in the description and have no special meaning.

[0034] According to some embodiments of the present application, please refer to Figure 1 to Figure 2 As shown, a method for controlling the stopping and rewinding of a strip based on strip roller welding is provided, comprising the following steps:

[0035] S1. The control system sends a stop signal to make the main traction shaft and the material belt start to move at a uniform deceleration speed from the preset speed.

[0036] Specifically, the welding shaft 1 and the main traction shaft 3 convey the material belt at a preset speed V1. When the control system sends a stop signal, the main traction shaft starts to decelerate uniformly, so as to decelerate the material belt uniformly to zero. The preset speed of the main traction shaft when the material belt moves in conjunction with the main traction shaft is 50-150 m / min, preferably 50 m / min.

[0037] Since the ultrasonic rolling process will hammer and stretch the material strip, the welding shaft will travel a slightly longer distance on the material strip than the material strip in the same period of time. Therefore, the speed of the configured welding shaft is slightly greater than the speed of the main traction shaft to ensure the normal transportation of the material strip. The specific speed may vary depending on the different tab materials of the material strip.

[0038] S2. During the deceleration process, the anvil is driven down by the cylinder to separate the material strip from the welding shaft, and the ultrasonic generator is stopped to complete the shutdown.

[0039] During the uniform deceleration of the material strip, when V1 decelerates to 10m / min, the cylinder drives the anvil to start falling, and the anvil drives the material strip to separate from the welding shaft. When the pressure feedback from the pressure sensor of the anvil is lower than 1960N, the ultrasonic generator stops working until the speed of V1 drops to zero.

[0040] During the uniform deceleration of the material belt, the value of the absolute encoder is read through the servo driver, and the position point P0 of the absolute encoder of the main traction shaft when the pressure of the anvil does not meet the standard and the position point P1 of the absolute encoder of the main traction shaft when the shutdown is completed are recorded.

[0041] S3, by controlling the material belt to move back a certain distance, the main traction shaft is rewound to the corresponding position.

[0042] Specifically, the distance that the material belt retreats in step S3 is:

[0043] S=P1-P0+S0

[0044] Among them, S represents the distance that needs to be rewound; P0 represents the absolute encoder position of the main traction shaft when the anvil starts to fall during shutdown and the anvil pressure does not meet the standard; P1 represents the absolute encoder position of the main traction shaft after the shutdown is completed; S0 represents the distance that the main traction shaft has traveled until the material belt moves again until the welding shaft starts ultrasonic rolling, that is, the distance that the material belt needs to travel during the uniform acceleration process.

[0045] Furthermore, since ultrasonic energy is still transmitted between the welding shaft and the material strip during the shutdown process, the distance P1-P0 at this time is also the distance at which a cold weld occurs in the material strip during the shutdown process.

[0046] Furthermore, in step S3, the welding axis movement is restarted to uniformly accelerate the material strip by a distance of:

[0047] (When V2+at1≤V1);

[0048] (When V2+at1>V1);

[0049] Among them, V1 represents the preset speed of the material belt movement; a represents the acceleration set when the material belt starts; V2 represents the set speed of the material belt when the anvil starts to rise, and V2<V1; t1 represents the time required for the anvil to start to rise to the target pressure value.

[0050] S4, restart the movement of the main traction shaft and the welding shaft to make the main traction shaft linked with the material belt to start moving again.

[0051] When the rewinding position of the material belt is determined, the control system sends a power-on signal to restart the machine and start the rotation of the main traction shaft and the welding shaft. The main traction shaft begins to move with uniform acceleration, so as to link the material belt to accelerate uniformly from the initial speed of zero to the preset speed V1.

[0052] S5. During the acceleration process, the anvil is raised by the cylinder linkage so that the anvil can abut the material strip against the welding shaft. When the real-time pressure detected by the pressure sensor reaches the target pressure, the ultrasonic generator is restarted to complete the restart.

[0053] When the material belt speed reaches V2 during the uniform acceleration process, the cylinder drives the anvil to start rising, and the anvil drives the material belt to abut against the welding shaft. When the pressure feedback from the pressure sensor of the anvil is greater than or equal to the target pressure value of 2000N, the ultrasonic generator starts working until the speed is accelerated to V1 to complete the restart process.

[0054] Furthermore, when the real-time pressure value detected by the pressure sensor reaches the target pressure value, the ultrasonic generator is restarted; when the real-time pressure value detected by the pressure sensor is less than 98% of the target pressure value, the ultrasonic generator is stopped.

[0055] Furthermore, V2 is set to 5 m / min during uniform acceleration, and the air pressure value when the cylinder links the anvil to move is 0.15-0.3 MPa, preferably 0.3 MPa.

[0056] S6. The material belt is linked to the main traction shaft to transport the material belt at a preset speed, and the material belt is ultrasonically rolled through the welding shaft.

[0057] When the material strip is accelerated to a preset speed V1 and is uniformly conveyed at the speed, ultrasonic rolling of the material strip by the welding shaft is achieved.

[0058] In the embodiments of the present application, the material strip may be configured as any one of copper foil, aluminum foil or composite foil, and the specific one may be selected according to actual needs.

[0059] According to a shutdown and rewinding control method based on strip roller welding provided in some embodiments of the present application, by rewinding the strip a certain distance and accurately determining the rewinding distance and position, it can effectively ensure the normal welding of the strip when restarting after shutdown, avoid over-welding or welding through when the strip is repeatedly welded, and improve the welding quality of the strip.

[0060] Accordingly, if Figure 2 The structural schematic diagram of the shutdown and rewinding control system based on strip roller welding of an embodiment of the present application is shown, in which the welding shaft 1 and the anvil 2 are respectively in contact with the upper and lower sides of the strip 4 to roll the strip 4, and the main traction shaft 3 provides a power source for the strip conveying.

[0061] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0062] The above description is only a detailed description of the preferred embodiments and principles of the present application. For ordinary technicians in this field, there will be changes in the specific implementation methods based on the ideas provided by the present invention, and these changes should also be regarded as the scope of protection of the present application.

Claims

1. A method for controlling the stopping and rewinding of a strip based on strip roller welding, characterized in that: The following steps are involved: S1, the control system sends a stop signal to make the main traction shaft and the material belt start to move at a uniform deceleration speed from the preset speed; S2. During the deceleration process, the anvil is driven down by the cylinder to separate the material strip from the welding shaft, and the ultrasonic generator is stopped to complete the shutdown; S3, by controlling the material belt to move back a certain distance, so that the main traction shaft is rewound to the corresponding position; S4, restart the main traction shaft and the welding shaft to make the main traction shaft and the material belt start to move again; S5. During the acceleration process, the anvil is raised by the cylinder linkage so that the anvil abuts the material strip against the welding shaft. When the real-time pressure detected by the pressure sensor reaches the target pressure, the ultrasonic generator is restarted to complete the restart; S6. The material belt is linked to the main traction shaft to transport the material belt at a preset speed, and the material belt is ultrasonically rolled through the welding shaft.

2. The method for controlling the stopping and rewinding of the strip based on strip roller welding according to claim 1 is characterized in that: The preset speed of the main traction shaft when linked with the material belt movement is 50-150 m / min, and the rotation speed of the welding shaft is greater than the rotation speed of the main traction shaft.

3. The method for controlling the stopping and rewinding of the strip based on strip roller welding according to claim 1, characterized in that: The main traction shaft and the welding shaft are equipped with absolute encoders.

4. The method for controlling the stopping and rewinding of the strip based on strip roller welding according to claim 1, characterized in that: The air pressure value when the cylinder links the anvil to move is 0.15-0.3 MPa.

5. The method for controlling the stopping and rewinding of the strip based on strip roller welding according to claim 1, characterized in that: The distance that the material belt retreats in step S3 is: S=P1-P0+S0 Among them, S represents the distance that needs to be rewound; P0 represents the absolute encoder position of the main traction shaft when the anvil starts to fall during shutdown and the anvil pressure does not meet the standard; P1 represents the absolute encoder position of the main traction shaft after the shutdown; S0 represents the distance the main traction shaft travels until the material strip moves again until the welding shaft starts ultrasonic rolling.

6. The method for controlling the stopping and rewinding of the strip based on strip roller welding according to claim 5, characterized in that: In step S3, the welding axis is restarted to uniformly accelerate the material strip by a distance of: (When V2+at1≤V1); (When V2+at1>V1); Among them, V1 represents the preset speed of the material belt movement; a represents the acceleration set when the material belt starts; V2 represents the set speed of the material belt when the anvil starts to rise, and V2<V1; t1 represents the time required for the anvil to start to rise to the target pressure value.

7. The method for controlling the stopping and rewinding of the strip based on strip roller welding according to claim 1, characterized in that: When the real-time pressure value detected by the pressure sensor reaches the target pressure value, the ultrasonic generator is restarted; when the real-time pressure value detected by the pressure sensor is less than 98% of the target pressure value, the ultrasonic generator is stopped.

8. The method for controlling the stopping and rewinding of the strip based on strip roller welding according to claim 1, characterized in that: The material strip is configured as any one of copper foil, aluminum foil or composite foil.

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