[0006] As far as the overall structure of the above-mentioned single-phase AC motor protector of CN100581043C is concerned, there are also the following disadvantages: First, because only the pin cavity for the spring piece and the pin (the patent is called the first pin) is formed on the fixing seat, so When the spring piece and the pin are accommodated in the pin cavity, the positioning effect of the fixing seat on the spring piece and the pin is fragile, so once there is a loose displacement, it will affect the relationship between the moving contact on the spring piece and the static contact on the pin. The effect of electrical contact or disconnection between them; secondly, because the heating wire cavity formed on the fixing seat is only for accommodating the heating wire, it has no limit effect on the heating wire, and arching (that is, arching) will appear in the actual use process. (1) situation, which affects the effect of the bimetallic sheet in contact with it as a whole; thirdly, due to the need to be equipped with a cover and a connecting piece as a carrier of the spring sheet (paragraph 3 and paragraph 4 on page 7 of the text of the manual), the relative structure Complicated, causing trouble for manufacturing and assembly
[0007] In terms of the overall structure of the aforementioned single-phase AC motor starter of CN100581043C, there are still following shortcomings: one, although the both sides of the bottom of the positive temperature coefficient thermistor can be significantly reduced by contacting the top protrusion with the bottom of the positive temperature coefficient thermistor. The support area of the device in the positive temperature coefficient thermistor cavity of the housing can significantly reduce the volume of the positive temperature coefficient thermistor, for example, the weight is reduced from 35-40g to 15-16g, but due to the positive temperature coefficient The side edges in the circumferential direction of the thermistor (the applicant defines it as the front and rear side edges) still need to be in contact with the front and rear walls of the positive temperature coefficient thermistor cavity in a large area, so it is not enough to reflect the ultimate energy-saving effect. The specific performance is that the volume of the positive temperature coefficient thermistor is still too large, and the weight is still too heavy
Theoretically speaking, forming a support wall on the front and rear cavity walls of the positive temperature coefficient thermistor cavity and forming a protrusion on the support wall can make up for the aforementioned deficiency and further reduce the volume of the positive temperature coefficient thermistor. The weight can be further reduced and the energy-saving effect can be reflected to the extreme degree, but repeated experiments by the applicant show that this idea is not advisable, because on the one hand, the aforementioned first and second pins and the positive temperature coefficient thermistor On the other hand, due to the excessive occupation of the space in the width direction of the positive temperature coefficient thermistor cavity, the installation of the starter is troublesome; secondly, because it is formed in the positive temperature coefficient thermistor cavity The structure of a pair of supporting walls at both ends of the device is relatively complicated, which leads to a relatively complicated mold for manufacturing the shell; third, since the top protrusion is formed on the supporting wall, the bottom of the positive temperature coefficient thermistor, that is, the bottom surface, is in contact with the The distance between the cavity bottom of the positive temperature coefficient thermistor cavity is the sum of the height of the support wall and the height of the top protrusion, so the situation of excessively raising the positive temperature coefficient thermistor causes the positive temperature coefficient thermal The positive temperature coefficient thermistor cavity protrudes from the upper part of the sensitive resistor, and the protruding part needs to be compensated by the raised cavity on the cover (the protruding part penetrates into the raised cavity), which increases the complexity of the cover on the one hand On the other hand, the contac