Lead shearing device for brush micromotor and with outgoing line carbon brush

Abstract

The invention discloses a lead shearing device for a brush micromotor and with an outgoing line carbon brush. The lead shearing device comprises a bottom plate, a power shaft, a guide mechanism, a transmission mechanism, a shearing mechanism and a limiting mechanism. The lower plate face of the bottom plate is connected with a shearing machining table. The guide mechanism is mounted on the upper plate face of the bottom plate. The power shaft is externally connected with a power source and penetrates the guide mechanism. The power shaft, the guide mechanism and the shearing mechanism are connected with the transmission mechanism. The positions of the power shaft and the guide mechanism are opposite to the position of the shearing mechanism. The limiting mechanism is mounted on the lower plate face of the bottom plate and is close to the side, opposite to the shearing mechanism, of the bottom plate. The lead shearing device has the advantages that the carbon brush lead shearing device with two shearing cavities is provided, production efficiency is improved, and meanwhile the market vacancy is made up; and the shearing quality of carbon brush lead shearing can be guaranteed by the device, the phenomena that single wires cannot be shorn off and wire drawing happens are effectively avoided in the shearing process, the machining efficiency and the product percent of pass are improved, and batch production is achieved.

Description

technical field [0001] The invention relates to a carbon brush lead wire cutting device, in particular to a lead wire cutting device with a lead wire carbon brush for a brushed micro-motor. Background technique [0002] At present, micro-motors on the market can be summarized into two types: brushed micro-motors and brushless micro-motors. Among them, the carbon brushes used in brushed micro-motors are generally divided into two types: carbon brushes without leads and carbon brushes with leads. kind. The lead-out carbon brush is a fixed structure of granular carbon brush and card-type copper sheet. The lead-out carbon brush means that when the carbon brush is formed, the braided copper wire is embedded in the carbon brush together. Compared with the lead-free carbon brush Carbon brushes with lead wires have better electrical and thermal conductivity, longer service life, higher power and stable output. In addition, carbon brushes with lead wires also have the advantages of ...

AI Technical Summary

Problems solved by technology

Since the thickness of the carbon brush body for micro-motors is generally 3mm to 5mm, the length of the lead wire is generally 10mm to 15mm, and the length tolerance is required to be within 1mm. figure 1 As shown, the actual space and height of the shearing scissors used are restricted to a certain extent. After the lead wire and the carbon brush body are pressed together by the upper and lower pressing heads, the shearing scissors are located on the upper and lower pressing heads. The micro-motor between the lower pressing heads is cut with a lead wire with a lead-out carbon brush. Due to the structural defects of the existing scissors, the length of the lead wire will be less than 10mm after the front cut, which cannot meet the length tolerance requirements.

[0004] In order to ensure the consistency of the lead wire length of each micro-motor carbon brush and the cutting length of the lead wire meets the accuracy requirements, it is necessary to ensure that the lead wire is in a straightened state when the lead wire is embedded in the brush body, because the brush body of the micro-motor carbon brush The size is too small, so that the thickness and embedding depth of the lead are limited. When the lead is cut, due to the own defects of the shearing scissors used, the lead will be displaced forward under the action of the shearing force. The component force of the shear force causes a relative tension between the lead wire and the brush body, which sometimes exceeds the maximum pull-off force that the lead wire can withstand, causing the embedded lead wire to be pulled out of the brush body. In addition, it will also cause The contact resistance between the lead wire and the brush body increases, resulting in abnormal performance of the carbon brush, which greatly affects the product qualification rate of the carbon brush of the micro-motor

[0005] Since the raw material particles for carbon brush molding are very fine, and its particle size is generally 21um to 74um, when the shearing scissors are working normally, the raised powder will fall on the surface of the scissors' edge, causing a gap between the two scissors. The increase of the gap not only leads to poor cutting of the leads and the inability of the scissors to work continuously for a long time, but also increases the wear of the scissors' edges, greatly shortening the service life of the scissors and increasing the processing cost

[0006] In order to ensure the conductivity and softness of the micro-motor carbon brush lead wire, the lead wire is usually braided copper wire, and the single wire diameter of the copper wire used is generally below Φ0.05mm. It is difficult to control the gap between the scissors within the specified range, so that the lead wire will be cut continuously and drawn during the cutting process. Each operation can only cut a single carbon brush lead wire, and the production efficiency is improved. less than guaranteed

[0007] Since the carbon brush material is strictly prohibited from contacting and mixing with lubricating grease and other substances, no lubricant can be added when the shearing scissors are working, resulting in poor industrial and mining conditions, which makes it difficult to design the kinematic structure of the scissors and ensure the long-term operation of the scissors. The absence of the carbon brush lead wire cutting device with lead-out wires for micro-motors leads to high manufacturing costs of such carbon brushes, and the quality cannot be guaranteed, making it impossible to mass-produce, which affects the production and processing of micro-motors, resulting in such The output of brushed micro motors with leads cannot meet the market demand

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