Extruding-type coating head with precisely controlled head and tail thicknesses

Abstract

The invention discloses an extruding-type coating head with precisely controlled head and tail thicknesses. The extruding-type coating head comprises a high-speed switching valve and an extruding head, wherein the high-speed switching valve is connected between a feeding pump and an extruding head and is used for intermittently cutting off a feeding channel between the high-speed switching valve and a seam of the extruding head; a variable containing device, which is communicated with the feeding channel and is used for changing the flow of paste in the feeding channel, is arranged below the feeding channel and comprises a containing device main body and a control piece for controlling the capacity change of the containing device main body; the containing device main body is communicated with the feeding channel; and when the control piece acts, the capacity of the containing device main body can be changed. The extruding-type coating head has the advantages of being capable of carrying out precise quantification and feed supplement at any time, being simple in structure, small in size and convenient to debug, and not occupying an extra space.

Description

technical field [0001] The invention relates to an extrusion type coating head which is mainly used for coating lithium battery substrates and whose head and tail thickness can be precisely controlled. Background technique [0002] The existing extrusion coating has the advantages of simple structure, miniaturized equipment, space saving, convenient debugging, etc., and is used by more and more manufacturers. However, when extrusion coating realizes intermittent coating, it uses a high-speed switching valve to achieve it. Since the piston of the high-speed switching valve moves up and down at high speed, it will generate an instant thrust or pull on the slurry, resulting in the existence of coating. The problem of thicker head and tail formation in intermittent position. [0003] In order to solve the problems of thick head and trailing in the prior art, people have proposed some solutions, as Chinese patent document CN102658255A just discloses a kind of intermittent ext...

AI Technical Summary

Problems solved by technology

This kind of coating machine adopts the cooperation of high-speed switching valve, switching valve and suction device. When the extrusion head feeds initially and when the feed stops, the slurry at the seam of the extrusion head is sucked back to avoid The thickness of the coating head and the tailing problem, however, in the actual application of this coating machine, because it adopts the method of vacuum suction, the return flow cannot be quantitatively controlled. The reason is that due to the expansion of the air, when The friction force generated by the switch valve and the inner wall of the pipeline connected with the switch valve to the slurry is relatively large (mainly due to the evaporation of the solute in the pipeline and the thickening of the concentration of the slurry), and the suction force of the vacuum adsorption is sometimes not enough to make the coating head The backflow of the slurry at the seam, if the suction is too large, the slurry will flow back too much due to the excessive adsorption force, and new problems will arise, such as thin head and tail, etc., which will also affect the coating. The quality of the cloth; in addition, this kind of coating machine also has the problem of complex structure, it not only needs the cooperation of high-speed switching valve, switching valve and suction device, but also needs to return the sucked slurry to the raw material barrel, so that The miniaturization of the coating machine is limited, and the space occupation is also large, and it is not convenient to debug

Moreover, this kind of coating machine also has the problem of not being able to replenish the material quantitatively in time if thin coating occurs during the coating process.

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