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AssigneeUbukata Industries Co., Ltd.
InventorsIsao Higashikata, Yoshihisa Ueda, Hideki Koseki
Estimating the term…
A thermal protector for a hermetic electrically-driven compressor including a hermetically sealed housing in which a power-supply terminal, an electric motor and a compressor are enclosed with a predetermined amount of refrigerant gas is disclosed. The thermal protector includes a thermally responsive switch having first and second lead terminal pins for securing first and second connecting terminals respectively and a holder formed from an electrically insulating material and including first, second and third cavities. Each of the first and second cavities has an opening in its one side. The first cavity accommodates the thermally responsive switch while the second cavity accommodates a secured portion between the lead terminal and the connecting terminal with a hardenable electrically insulating filler filling up the second cavity. Alternatively, the second connecting terminal is secured to a wall of the holder by an insert molding so as to extend through the wall, instead of use of the filler.
A thermal protector for a hermetic electrically-driven compressor including a hermetically sealed housing in which a power-supply terminal is disposed and an electric motor and a compressing means are enclosed with a predetermined amount of refrigerant gas, the thermal protector comprising:
A thermal protector for a hermetic electrically-driven compressor including a hermetically sealed housing in which a power-supply terminal is disposed and an electric motor and a compressing means are enclosed with a predetermined amount of refrigerant gas, the thermal protector comprising:
Dependencies are inferred from the claim text.
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No related US applications are recorded in the indexed filing history.
Encapsulated in sealed miniaturised housing: mounted on controlled apparatus
For measuring, monitoring, testing, protecting or switching: devices for sensing temperature, or actuated thereby
Electric connections to or between contacts; Terminals: characterised by the use of a plug and socket connector
Electric switches
Term ended 30 Aug 2014 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
1. Field of the Invention
This invention relates to a thermal protector protecting, against an overcurrent and/or an overheat, an electric motor enclosed in a hermetically sealed housing of an electrically-driven compressor, the housing further enclosing a compressing means and a predetermined amount of refrigerant gas, and more particularly to such a thermal protector of the type that it is disposed in the compressor housing.
2. Description of the Prior Art
Other objects, features and advantages of the present invention will become clear upon reviewing the following description of preferred embodiments thereof, made with reference to the accompanying drawings, in which:
FIG. 1 is a longitudinal sectional view of a hermetic electrically-driven compressor to which a first embodiment of a thermal protector in accordance with the present invention is applied;
FIG. 2 is a sectional view taken along line 2--2 in FIG. 1;
A first embodiment of the present invention will be described with reference to FIGS. 1 to 6. Referring to FIG. 1, a hermetic electrically-driven compressor 1 comprises a hermetically sealed high-pressure housing 3 including a top cover 2A on which a thermal protector 11 of the first embodiment is mounted so as to be located in the housing 3, and a receptacle 2B. The housing 3 encloses therein a conventional electric motor 4 and a conventional compressing means 5 driven by the motor 4. A suction pipe 6 extends through a lower peripheral wall of the housing 3 and is then connected to the compressing means 5 so that refrigerant gas delivered from an external heat exchanger (not shown) is introduced into the interior of the compressor housing 3. The refrigerant gas compressed by the compressing means 5 is discharged into the compressor housing 3, flowing along the periphery of the motor 4. The refrigerant gas is then circulated into the heat exchanger through a discharge pipe 7 extending through the cover 2A. A glass-insulated power-supply terminal 8 air-tightly extends through the cover 2B of the compressor housing 3 and is then secured in position by way of welding.
The power-supply terminal 8 includes three electrically conductive pins 8A, 8B and 8C. Three connecting tab terminals 8D are mounted on ends of the conductive pins 8A, 8B, 8C located in the compressor housing 3 respectively, as shown in FIGS. 2 and 3. Lead wires 10 extending from windings of the motor 4 are connected to the conductive pins 8B, 8C respectively. The thermal protector 11 is connected to the other conductive pin 8A.
The thermal protector 11 will now be described with reference to FIGS. 3 to 6. The thermal protector 11 comprises a thermally responsive switch 12 and an electrically insulating holder 13 accommodating the thermally responsive switch 12, as shown in FIG. 5. The thermally responsive switch 12 comprises a hermetically sealed metal casing 12D and a bimetallic thermally responsive element (not shown) enclosed in the casing 12D, as well known in the art. The structure of such a thermally responsive element is disclosed in U.S. Pat. No. 5,015,985, for example.