CN2218263Y

CN2218263Y - Self heat-protector of refrigerator compressor

Info

Publication number: CN2218263Y
Application number: CN 93237988
Authority: CN
Inventors: 吴宗勤; 牛平国
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-11-24
Filing date: 1993-11-24
Publication date: 1996-01-24
Anticipated expiration: 2003-11-24

Abstract

The utility model discloses a self heat-protector of a refrigerator compressor, which is suitable for overcurrent and overheat protection of the refrigerating compressor of a full closed type. The utility model is composed of an insulating casing (4), and series circuits which are positioned inside the casing. The series circuits are composed of heating wires (1) and bimetallic strips (2). The utility model is characterized in that the upper part of the bimetallic strips (2) of the utility model is provided with PTC thermistors (8) which are connected with the bimetallic strips (2) in parallel.

Description

Self-insurance's refrigeration compressor heat protector

The utility model relates to a kind of thermosensitive bimetal hot protective relay, is applicable to the overcurrent and overheating protection of hermetically sealed compressor.

At present, hermetically sealed compressor both domestic and external generally uses the thermosensitive bimetal hot protective relay to do overcurrent, overtemperature protection.It mainly is the circuit of being connected with thermosensitive bimetal 2 by electric heating wire 1 to be set constituted (referring to Figure of description 1) in insulation crust 4 that described thermosensitive bimetal heat is protected relay.When refrigeration compressor generation overcurrent or overheating fault, two of described thermosensitive bimetal 2 upwarps, cut-off loop current protection compressor, and after compressor temperature reduces, the thermosensitive bimetal 2 connection power supply that resets again.Practice is found; causing compressor overcurrent or overheated not eliminating of fault; or the unloading time of compressor then disconnects repeatedly, connects than thermosensitive bimetal hot protective relay under resetting time of the thermosensitive bimetal long situation, and with the sound of clatter, clatter, clatter.This will make compressor be subjected to the impact of excess current for a long time and burn.

In view of there is above-mentioned deficiency in prior art, the purpose of this utility model is to disclose a kind of self-insurance's refrigeration compressor heat protector.

The technical solution of the utility model realization above-mentioned purpose comprises by insulation crust and is located at the hot protective relay of being made up of electric heating wire and thermosensitive bimetal in this shell that series circuit constituted; the top that it is characterized in that the thermosensitive bimetal in the described hot protective relay is provided with the PTC thermistor, and this PTC thermistor and thermosensitive bimetal are connected in parallel.In case compressor overcurrent or overheated, heat-sensitive duplex metal two upwarps disconnection, power supply is then powered to compressor through described PTC thermistor, flow through electric current moment of PTC thermistor can make it reach transition temperature, resistance value increases thousands of times, in quitting work the loop, back, the compressor dead electricity still have small electric current to keep the hot of PTC thermistor, the PTC thermistor is passed to thermosensitive bimetal with a heat energy part that is produced and is realized self-insurance simultaneously, avoid the startup repeatedly of compressor effectively, guarantee the safety of compressor.After the fault of compressor is got rid of, as long as cut off the power supply a few minutes artificially, make the cooling of PTC thermistor, heat-sensitive duplex metal restores to the original state and can normally come into operation.

Below in conjunction with accompanying drawing and a most preferred embodiment the utility model is explained in further detail.

Fig. 1 is the structural representation of the employed a kind of hot protective relay of present freezer compressor;

Fig. 2 is the structural representation of a most preferred embodiment of the utility model;

Fig. 3 carries out the electrical schematic diagram of a kind of concrete controlling schemes of overcurrent and overheating protection for using the utility model to freezer compressor, is the electrical schematic diagram of self-insurance's refrigeration compressor heat protector described in the utility model in the frame of broken lines among the figure.

With reference to Fig. 2, one of being located in the insulation crust 4 of tenminal block 5 is a tiger, PTC thermistor 8 is located in the described tiger, upper side is close to the maxilla of described tiger, downside falls within the upper end portion of the adjusting screw 7 of thermosensitive bimetal 2, and is in parallel with thermosensitive bimetal 2 on circuit, under the normal condition, with PTC thermistor 8 shorted on both ends, empty calory produces all the time by thermosensitive bimetal 2.In case refrigeration compressor overcurrent, electric heating wire 1 heating, perhaps the compressor self-heating all can make two of thermosensitive bimetal 2 upwarp, and moving contact 3 and tenminal block 5 are located at the lower jaw of interior one tiger of insulation crust 4 throws off, meanwhile just cut-in operation loop of PTC thermistor.Because PTC thermistor 8 resistance value when no current flows is very little, so upwarp the bigger electric current of the Shi Zeyou PTC thermistor 8 of flowing through at thermosensitive bimetal 2 two.Because PTC thermistor 8 is a kind of positive temperature coefficient electronic components with quick heating, so just can reach transition temperature in a flash what bigger electric current was flowed through it, its resistance value thousandfold ground increase quits work compressor again.But still have several milliamperes of faint electric currents to flow through this moment, keeps the hot of PTC thermistor 8.Some passes to thermosensitive bimetal 2 heat energy that PTC thermistor 8 is produced, and makes it keep two to upwarp.This moment, compressor just quit work all the time as long as the civil power end cuts off, can be because of long-time overheated not burning.

Fig. 3 provides the example of a kind of concrete using method of the utility model, is indicated as malfunction alarm by the circuit of resistance flowing resistance 9 and tutorial light 10 series connection in two of PTC thermistor 8 parallel connection one.Under the normal condition, the series circuit of resistance 9 and tutorial light 10 is by thermosensitive bimetal 2 and PTC thermistor 8 short circuits, when compressor 11 breaks down and overcurrent stream or when overheated, the resistance of the parallel circuit of thermosensitive bimetal 2 and PTC thermistor just rapidly increases to hundreds of kilo-ohm, its terminal voltage is added to two of the series circuit of resistance 9 and tutorial light 10, and tutorial light 10 is luminous warning.Have only the fault of machine to be compressed to get rid of, thermosensitive bimetal 2 reinstatement rear indicator lights just can cease and go out.

Claims

1, a kind of self-insurance's refrigeration compressor heat protector; comprise by insulation crust (4) and be located at the hot protective relay of forming by electric heating wire (1) and thermosensitive bimetal (2) in this shell that series circuit constituted; the top that it is characterized in that the thermosensitive bimetal (2) in the described hot protective relay is provided with PTC thermistor (8), and this PTC thermistor (8) is connected in parallel with thermosensitive bimetal (2).