JPH0447433Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an overload protection device for a hermetic compressor constituting a refrigeration cycle.

Conventional structure and its problems Conventionally, this type of hermetic compressor was
As shown in the figure, a motor element 102 and a compressor element 103 driven by the motor element 102 were disposed inside a closed container 101, and a glass insulated terminal 105 was further provided on the upper part of the closed container 101. . The motor element 102 then includes a stator 106
and the rotor 107 and the winding end portion 10 of the stator 106
8. The overload protector 109 is fixed to 8.

However, in this conventional configuration, the overload protector 1
09 to the winding end 108, the installation dimensions of the overload protector 109 are strictly regulated.
07, it is necessary to secure a gap with the sealed container 101 to prevent insulation failure, and there is a problem that it takes a lot of time to shape the winding end 108 and install the overload protector 109, leading to high costs. Ta.

Purpose of the invention This invention solves the above conventional problems.
The purpose is to enable the installation of overload protectors at low cost.

Structure of the invention In order to achieve this objective, the present invention provides a plate-shaped elastic body to which an overload protector is attached to the upper inner surface of the hermetic container of a hermetic compressor, and the overload protector is attached to this plate-shaped elastic body. In addition to being elastically held and fixed, the overload protector and the motor stator lead wire are connected by crimp terminals.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 3 to 5.

First, the schematic structure of the hermetic compressor will be explained with reference to FIG.

In FIG. 3, reference numeral 1 denotes a closed container, inside which a motor element 4 consisting of a rotor 2 and a stator 3 and a compressor element 6 driven by the motor element 4 via a crankshaft 5 are arranged. It is set up. The closed container 1 has a body shell 7 to which the stator 3 and the compressor element 6 are fixed, a lower lid 9 to which the support legs 8 are fixed, and a lower lid 9 to which the closed container 1 is kept airtight. It is comprised of an upper lid 11 to which a glass insulated terminal 10 that conducts electricity is welded and fixed. Furthermore, a discharge pipe 13 is welded and fixed to the upper lid 11 together with a holding device 12 that holds an overload protector 16, which will be described later. 14
is a suction pipe which is welded and fixed to the body shell 7.

Next, the structure of the holding device 12 will be explained with reference to FIG. Here, the same parts as in FIG. 3 are given the same numbers and the explanation will be omitted.

In FIG. 4, the holding device 12 of the overload protector 16 is provided on the upper lid 11.
1, an overload protector 16, an insulator 17 surrounding the overload protector 16, an elastic plate 18 gripped from above, and an elastic plate 1
8 to the metal plate 15 with bolts 19. Furthermore, the end 20 of the overload protector 16
is a male crimp terminal into which the female crimp terminal 22 of the lead wire 21 from the stator 3 is inserted, and the glass insulated terminal 10.
It is composed of a lead wire 24 that extends to.

In the above configuration, the compressor element 6 is driven by supplying electric power to the electric motor element 4, and the refrigerant gas entering from the suction pipe 14 is compressed by the compressor element 6 to become high temperature and high pressure. The refrigerant gas then flows into the closed container 1, cools the motor element 4, and is then discharged from the discharge pipe 13 to flow into a well-known refrigeration cycle (not shown).

Here, when the thermal load increases or the load applied to the motor element 4 becomes heavier due to fluctuations in the power supply voltage, the current flowing through the motor element 4 increases and the temperature of the high-pressure gas within the closed container 1 also rises. On the other hand, the overload protector 16 operates the bimetal inside the overload protector based on the temperature of the surrounding high-pressure gas and the current flowing through the motor element 4, and interrupts the electric circuit, so the operation of the motor element 4 is stopped. do.

When the temperature of the refrigerant gas in the closed container 1 decreases, the overload protector 16 automatically returns and the motor element 4 resumes operation. In a high-pressure hermetic rotary compressor, the stator 3 of the motor element 4,
The difference between the winding temperature and the high-pressure gas temperature in the sealed container 1 is small, and by detecting the gas temperature at the overload protector attachment part, the rise in the winding temperature of the motor element 4 can be suppressed, and the temperature of the motor element 4 can be reduced. Burnout can be prevented.

Therefore, the overload protector 16
This is similar to directly detecting the winding temperature and current, and it is possible to prevent the motor element 4 from burning out. Further, the number of man-hours for manufacturing the electric motor element 4 can be reduced, and the structure is simple and can be produced at low cost.

In this embodiment, the overload protector 16 is installed from a direction perpendicular to the rotation axis direction of the motor element 4, but as shown in FIG. 6, the shape of the plate-shaped elastic body 18 is slightly changed. The overload protector 16 may be installed from the direction of the rotation axis.

Effects of the invention As described above, the present invention separates the overload protector from the motor stator, attaches the overload protector holding device inside the upper lid of the airtight container, and connects the overload protector and the motor stator lead wire. Since the connection between the overload protector and the motor stator lead wire is made using crimp terminals, the connection between the overload protector and the motor stator lead wire is easy and can be made at any time.Furthermore, since the overload protector is exposed to the atmosphere inside the sealed container, the temperature of the motor elements may vary. It is also possible to sufficiently detect rises, making it easy to prevent burnout of the motor and ensure reliability. Furthermore, the distance to the fixing position of the overload protection device is short and the structure is simple, so vibration is less likely to occur, and there is little variation in the fixing position, ensuring reliability in assembly, transportation, and operation. It has the following effects.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of a conventional hermetic compressor, Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1, and Fig. 3 is an overload protection device according to an embodiment of the present invention. Fig. 4 is a detailed view of the main parts showing how the overload protector is installed in the same compressor, and Fig. 5 is a longitudinal cross-sectional view of a hermetic compressor that has an overload protector in the same compressor. A perspective view of the elastic body, FIG. 6 is a view corresponding to FIG. 4 showing another embodiment of the present invention. 1... Airtight container, 4... Electric motor element, 18...
Compressor element, 10... Glass insulated terminal, 11...
Upper lid, 12... Holding device, 15... Sheet metal fitting, 1
6...Overload protector, 18...Plate-shaped elastic body.

Claims (1)

[Scope of utility model registration request] An electric motor element and a compression element driven by the electric motor element are provided in the airtight container, and power is supplied to the upper lid of the airtight container from outside the airtight container to the electric motor element inside the airtight container, Glass insulated terminals that keep the refrigerant gas airtight,
A hermetic compressor is provided with an overload protector that opens and closes an electric circuit to the motor element between the glass insulated terminal and the motor element depending on the ambient temperature and the current flowing to the motor element, and the overload protector is held by a plate-shaped elastic body, and this plate-shaped elastic body is fixed to the inner surface of the upper lid of the sealed container, and the overload protector and the motor element stator lead wire are connected by crimp terminals. An overload protection device for a hermetic compressor characterized by the following.