JP2782173B2 - Protection device for hermetic electric compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is mounted in a sealed housing of a hermetic electric compressor, and in particular, is mounted directly on the inside of a hermetically sealed housing of a power supply terminal for an electric motor sealed with glass or the like on the hermetic housing. The present invention relates to a protection device that also serves as a connector for connecting a sealed terminal for power supply and a motor and, at the same time, responds to the temperature of the refrigerant in the sealed housing to cut off an electric circuit when the motor is overheated and protect the motor from burning. Things.

[0002]

2. Description of the Related Art There are various types of conventional protective devices for hermetically sealed electric compressors in which an airtight internal protector (hereinafter referred to as a protector) is arranged in a hermetically sealed housing of the electric motor. A structure that is mounted on a sealed terminal of a sealed housing has recently been proposed. For example, in Japanese Unexamined Utility Model Publication No. 5-27291, one lead terminal of a protector is connected to one lead wire from an electric motor, and a connection terminal is fixed to the other lead terminal, and this connection terminal is housed in a cluster socket. In this case, the protector is fixed and held on the side surface of the cluster socket, and the cluster socket is attached to the sealed terminal. According to this method, the protector can be easily mounted, but since the protector is fixed to the cluster socket with only one connection terminal, the lead wire from the motor is pulled when the cluster socket is mounted on the sealed terminal. For example, there is a possibility that an excessive force, in particular, a force in a twisting direction may be applied to the connection terminal or the lead terminal of the protector.

On the other hand, Japanese Patent Application Laid-Open No. Hei 3-156183 discloses a case where a protector is attached to a cluster socket and then both are integrally covered with a heat-shrinkable insulating tube (hereinafter referred to as a tube). . In this example, the protector is fixed to the cluster socket with a tube so that no excessive force is applied to the terminal of the protector even if the lead wire from the motor is pulled when the cluster socket is attached to the sealed terminal. Have been. However, in the example of Japanese Patent Application Laid-Open No. 3-156183, not only the number of parts is increased, but also the tube must be contracted while the protector and the cluster socket are connected to the electric motor. Since a hole for connecting the conductive terminal is formed in the tube, there is a problem in that the tube has directionality at the time of mounting and the workability is significantly deteriorated.

Accordingly, the present applicant has filed Japanese Patent Application No. 6-329468.
In Japanese Patent Application No. 7-116379, a protective device for a hermetic electric compressor in which a flange portion of a protector is gripped and fixed by a cluster socket is proposed. In these sealed electric compressor protection devices, a protector is attached to the side surface of the cluster socket so as to be substantially flush with the cluster socket, thereby reducing the thickness of the protection device.

[0005] These protection devices are well known in the event of an abnormality such as overheating or overcurrent by connecting one terminal of the protector to a common terminal pin of a sealed terminal and connecting the other terminal to a common lead wire of a motor. The contact between the contacts of an opening / closing mechanism using the thermally responsive element is opened to cut off the power supply to the electric motor.

[0006]

However, when the sealed terminals are arranged in the upper container of the sealed housing, the common terminal pins may be located on the side closer to the outer peripheral portion of the inner wall of the upper container due to the arrangement of the terminal pins. In this case, however, in the above-described protection device, the distance between the common terminal pin and the inner wall of the upper container is short, so that the container of the protector hits the upper container, so that it cannot be mounted. There is also a demand that a protector closer to the motor be detected in order to detect heat generation of the motor more quickly.

[0007]

SUMMARY OF THE INVENTION Accordingly, in the protection device for a hermetic electric compressor of the present invention, the hermetic terminal is mounted inside the hermetic housing of a hermetic terminal which is hermetically fixed to the hermetic housing of the hermetic electric compressor. Protector for electric compressor,
The protector is a flange portion is formed by a lid section has a portion parallel to the longitudinal direction of the metal container to hermetically with accommodating the thermally responsive switch mechanism in a metal container formed in a dome-type, the protector 2 Terminals.
One of the two terminals of the protector has the sealed terminal .
Penetrating equipped with receptacles for one mating terminal pins that are insulated fixed, the other terminal yield in the sealed housing
Connected to the common lead wire paid by an electric motor, further, each for connecting the motor windings to the terminal pin of the sealed terminal
Substantially flat with three terminal insertion holes into which the terminals are inserted
Hermetic electric compressor consisting of cluster sockets with various bodies
In use the protective device, one having the terminal insertion hole in the center of one common terminal insertion hole and without, a pair of hook-shaped part at the tip for gripping the longitudinal direction of the flange portion on one surface of the body of this cluster socket Rail-shaped holding portion is provided in parallel with the common terminal insertion hole, and the holding portion of the cluster socket is parallel to the longitudinal direction of the flange portion of the protector.
Is gripped such portions, when the receptacle to the common terminal insertion hole is inserted to a position corresponding to one of terminal pins of said sealed terminal, most of the metal container of the protector is exposed to the body outside the cluster socket, It is characterized in that the heat sensing part is integrally connected so as to be in good contact with the flow of the refrigerant.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. A so-called high-pressure housing type hermetic electric compressor 1 whose internal structure is shown in FIG. 1 and FIG. 2 has a hermetic housing constituted by an upper container 2 and a lower container 3, and a known structure is provided in the hermetic housing. The electric motor 4 and the compressor 5 are accommodated and installed. A suction pipe 6 for introducing a refrigerant sent from a heat exchanger (not shown) is connected to the compressor 5 through the hermetic housing, and the refrigerant compressed by the compressor 5 passes through the electric motor 4. Is discharged to the upper part in the closed housing, and sent again from the discharge pipe 7 to the heat exchanger. A sealing terminal 8 is hermetically fixed to a window hole 2A provided in the upper container 2 by means such as welding. Sealed terminal 8
A plurality of terminal pins 8A penetrate the front and back, and are hermetically supported and fixed via an insulating material such as glass or ceramic, so that an external power source (not shown) is connected to the electric motor 4 in the sealed housing. It plays the role of a member. A lubricating oil 9 for the electric motor 4 and the compressor 5 is sealed in the bottom of the sealed housing.

A protection device 10 is mounted on the inside of the sealed housing of the sealed terminal 8 so as to be fitted as a socket with the terminal pin 8A as a plug. Is electrically connected to each of the plurality of lead wires 11 from the other.

A protection device (hereinafter referred to as a protection device) 10 for a hermetic electric compressor in this embodiment will be described.
As shown in FIGS. 3 to 7, the protection device 10 includes a protector 13 and a cluster socket 12 supporting the protector. The cluster socket 12 is made of an insulating material such as a synthetic resin, and is slightly flattened.
As shown in (1), a holding portion 12A for gripping the protector 13 is formed on one of the front and back surfaces thereof, so that it can be connected to the protector 13. The protector 13 is a form generally called an internal protector, in which an opening / closing mechanism using a thermally responsive element such as a bimetal is sealed inside a metal hermetic container. Japanese Unexamined Patent Publication No. Hei 2-227928 and
No. 36335, which serves to interrupt the electric circuit when the motor 4 is overheated or overloaded, for example, by transmitting the gas temperature touching the surface of the metal container to the internal heat responsive element. is there.

As shown in FIG. 4, one terminal 13A and 13B of the protector 13 in this embodiment
A terminal arm piece 15 is fixed to A by welding or the like.
The terminal arm piece 15 is bent at the base of the L-shape, and its tip extends parallel to the longitudinal direction of the protector 13. The tip is formed with a receptacle part 17 that can be fitted and connected to one terminal pin 8A. I have. The shape is such that when the terminal arm piece 15 is inserted into the hole of the cluster socket 12, the terminal arm piece 15 is locked at the back of the hole, and corresponds to a common socket hole 12F of a later-described cluster socket on the bottom surface 17A. At the position, a through hole 17B into which the terminal 8A is inserted is provided as shown in an enlarged sectional view in FIG. The shape of the receptacle is not limited to the shape shown in the embodiment, but various shapes can be used as long as the receptacle is inserted and fixed in the cluster socket and the terminal pin of the sealed terminal is inserted and connected. Nor.

A tab terminal piece 18 is fixed to the other protector terminal 13B. The tab terminal pieces 18 extend in directions opposite to the terminal arm pieces 15, and are arranged in a line and parallel to the longitudinal direction of the protector 13. The protector 13 houses a well-known thermally responsive opening / closing contact mechanism inside a container 13C, and has an opening 13D sealed with a lid plate 13E. The container 13C has a slightly enlarged opening 13D and a lid plate that seals the opening 13D. It has a flange portion 13F having a portion parallel to the longitudinal direction constituted by the periphery of 13E.

The cluster socket 12 is shown in FIG.
Three terminal insertion holes 1 opening arranged in one side surface thereof as to
2B, 12C, and 12D are provided, among this, the central
Of the protector 13 is inserted into the common terminal insertion hole 12C.
The tuckle unit 17 is inserted. Here both protectors 13
The terminals 13A and 13B are slits 12 of the cluster socket.
After entering the inside of J, the receptacle portion 17 is moved as shown in FIG.
The aforementioned through holes 17B correspond to the common socket holes 12F.
To a predetermined position . Also, the terminal insertion holes 12B,
12D shows the motor mounted on the end of the motor lead wire 11
No receptacle is inserted and held. In this way,
On the surface opposite to the surface where the slit 12J is provided
Socket hole 12E that was, 12F, 12G and the receptacle
Receptors corresponding position is defined, and the terminal insertion hole of the
Kuru has been configured, each held in a known locking mechanism
You . This application, three things center of the insertion hole is in a configuration for supporting the protector, the central common terminal interpolation In this application
The insertion hole 12C is inserted to the right in FIGS. 5A and 5B.
Although the hole protrudes long , this portion 12H is shown in FIG.
As described above, the insulating cover 12H serves as an insulating cover for covering the periphery of the tab terminal piece 18 from the surroundings . For example, if there is no problem in insulation in connection with wiring, the insulating cover 12H may be omitted.

[0014] The slit 12 of the cluster socket 12
As described above, the protector holding portion 12A is formed symmetrically on both sides of the slit 12J and in parallel with the central common terminal insertion hole on the surface where J is provided. The distal end of the protector holding portion 12A has a small cross-section and has a small hook shape and faces each other to form a kind of rail shape, whereby the parallel portion of the flange portion 13F of the protector can be gripped.

As described above, the protector 13 is connected to the cluster
Li the common terminal insertion hole 12C in mounting the Tsu DOO 12
Insert the receptacle portion 17 and the tab terminal 18, a flange portion 13F of the protector 13 by Rukoto advancing the insert
The parallel portions in Figure 3 is gripped protector holding portion 12A of the
Hold as shown. Common terminal insertion of this protection device 10
The receptacle ( not shown) attached to the end of the common lead wire 11A of the electric motor is inserted and locked into the tab terminal piece 18 facing the insertion hole 12C , and the electric motor is inserted into the terminal insertion holes 12B and 12D.
(Not shown) connected to the tip of the lead wire 11 from
Connect the receptacle to the socket holes 12E and 12G as described above.
Protective equipment by inserting and locking correspondingly
The connection between the device 10 and the motor 4 is completed.

The use and operation of the protection device 10 configured as described above will be described. As shown in FIGS. 1 and 2, the protection device 10 has the terminal pins 8A and the socket holes 12E, 12E from the lower side of the sealed terminal 8, that is, from the inside of the sealed housing, with the sides with the socket holes 12E, 12F, 12G facing upward.
F and 12G are fitted and mounted. Even when a force such as pulling or twisting acts so that the force from the motor lead wire 11 tries to separate the protector 13 from the cluster socket 12 via the tab terminal piece 15 at the time of mounting, the protector 13 does not 13F is the holding part 12A
Therefore, there is no action force that causes deformation and damage to each terminal portion. The upper case 2 and the lower case 3 of the electric compressor in which the protection device 10 is mounted on the sealed terminal 8 are hermetically connected and used for operation as is well known.

During normal operation, the temperature of the refrigerant in the compressor closed housing is below a predetermined value, and the current to the motor is also below the rated value. By setting the operating temperature of the heat responsive body in the protector 13 to be slightly higher than the predetermined value when the motor current is the rated value in advance, energization to the motor 4 is maintained. If the rotation of the motor 4 during operation is restrained or becomes overloaded due to the occurrence of some abnormality, the winding current and temperature of the motor 4 abnormally rise, and the refrigerant temperature also rises. In this state, the container 13C of the protector 13 contacts the refrigerant to transmit the temperature to the inside of the container, and an internal heat responsive body (not shown) performs an electric circuit cutoff operation to protect the electric motor 4 from burning.

In the above description, the protection device used in the hermetic electric compressor of the high-pressure housing type has been described. However, the protection device can be mounted at a position where the rise of the refrigerant temperature in the event of an abnormality can be reliably detected. Then, the protection device of the present invention
The same can be used as it is for a so-called low-pressure housing type hermetic electric compressor.

In the above embodiment, the protector having two lead terminals has been described.
Even if the container is a one-pin type that also serves as one of the lead terminals, the same operation can be performed only by slightly modifying the shape of each attached terminal piece. Needless to say, the motor lead wire can be directly connected to the protector without using the tab terminal piece.

[0020]

According to the protection device for a hermetic electric compressor of the present invention, the flange portion of the protector is gripped and fixed by the cluster socket, so that the connection terminal or the lead terminal of the protector cannot be forcibly applied, especially in the torsion direction. In addition, even if the common terminal pin is located close to the outer peripheral part of the inner wall of the upper container due to the arrangement of the terminal pins of the sealed terminal, the container of the cluster socket of the protective device and the container of the protector will hit the upper container. It can be installed without.

According to the protection device for a hermetic electric compressor of the present invention, the protector can be brought closer to the electric motor, so that the overheating state of the electric motor winding can be detected more quickly.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a hermetic electric compressor to which an embodiment of a protection device according to the present invention is attached.

FIG. 2 is a sectional view of the hermetic electric compressor shown in FIG.

FIG. 3 is a perspective view of an embodiment of the protection device for a hermetic electric compressor of the present invention.

FIG. 4 is a perspective view of an internal protector used in the protection device of FIG. 3;

FIG. 5 is a three side view of a cluster socket used in the protection device of FIG. 3;

FIG. 6 is a perspective view of a cluster socket used in the protection device of FIG. 3;

FIG. 7 is a partial sectional view of the protection device of FIG. 3;

FIG. 8 is an enlarged cross-sectional view of the receptacle shown in perspective in FIG.

[Explanation of symbols]

 1: Sealed electric compressor 2: Upper container 3: Lower container 4: Motor 5: Compressor 6: Suction pipe 7: Discharge pipe 8: Sealed terminal 8A: Terminal pin 9: Lubricating oil 10: Protection device 11: Lead wire 12: cluster socket 12A: holding portion 12B, 12C, 12D: terminal insertion hole 12E, 12F, 12G: socket hole 12J: slit 13: protector 13A, 13B: terminal 13F: flange portion 15: terminal arm piece 17: receptacle 18: Tab terminal strip

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) F04B 39/00 106 F04C 29/00 H02K 5/22

Claims (1)

(57) [Claims] 1. An internal protector for an electric compressor mounted inside a hermetically sealed terminal hermetically sealed to a hermetically sealed housing of an hermetic electric compressor, wherein the protector has a dome-shaped cross section. the flange portion is formed by a lid having a portion parallel to the longitudinal direction of the metal container to hermetically with accommodating the thermally responsive switch mechanism within, the protector has two terminals, both terminals of the protector One of them is the sealed terminal
Includes a receptacle for one mating terminal pins which are insulated fixed through the, the other terminal connected to the common lead wire housed an electric motor in the closed housing and terminal pins of said sealed terminal
Terminal is inserted for connecting respectively the motor windings down
Three terminal insertion holes substantially flat body of the cluster socket sealed electric compressor protection device odor <br/> consisting with Te, the terminal insertion hole in the center of one common terminal insertion hole and without, this cluster A cluster-shaped holding portion having a kind of rail-shaped holding portion having a pair of hook-shaped portions at one end for gripping the longitudinal direction of the flange portion on one surface of a socket body, in parallel with the common terminal insertion hole. wherein the longitudinal direction parallel portion of the flange portion of the protector is gripped, when the receptacle to the common terminal insertion hole is inserted to a position corresponding to one of terminal pins of said sealed terminal, most of the metal container of the protector Are integrally coupled so as to be exposed to the outside of the body of the cluster socket.