JP2657759B2 - Protector 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 relates to a movable electric contact driven by a heat responsive body made of a metal whose shape changes according to different temperatures, such as a bimetal, in order to protect the motor from overload in a hermetic electric compressor. A mechanism for opening and closing the current flowing through the motor between the movable contact and the pair of fixed contacts is provided in the sealed outer box, and the improvement is made to facilitate the mounting of the protector on the outer box and part of the compressor. The present invention proposes a protector for a hermetic electric compressor provided with the above mechanism.

[0002]

2. Description of the Related Art Conventionally, a protector of a hermetic electric compressor of this type is embedded in a coil end portion of a stator winding of a motor housed in a hermetically sealed container, or is closely fixed on the coil end. A method such as binding with a thread was adopted. Detects abnormal currents or abnormal temperatures in the motor, shuts off the current supplied to the motor, protects the windings of the motor from overheating, and automatically returns to supply the current to the motor. The operation as a protection switch is performed such that the operation is continued, and if there is an abnormality, the cutoff / energization is repeated again.

[0003] The present applicant has also filed Japanese Patent Application No. 61-170442.
Proposes a protector for hermetic electric compressors. This closed type electric compressor protector will be described. In FIG. 4, a sealed container 10 is a rigid iron container portion.
11 and a lid portion 12. A compressor P is disposed near a lower end of a rotating shaft S fixed to a rotor R of the electric motor, and an outer peripheral portion PO of the compressor P is fixed below the closed casing 10. The motor stator F disposed around the rotor R has its outer periphery fixed from the center of the container portion 11 to the vicinity of the joint end E. When the inner surface of the sealed container 10 is a circle, the outer periphery of the stator F is formed in a polygonal shape such that a gap is formed in the axial direction instead of being in close contact with the entire surface. The stator winding is wound around the stator F while being electrically insulated, and its coil ends W are respectively extended at the upper and lower ends of the stator F as shown in the drawing, and are formed by binding with, for example, nylon thread. . Although a heat medium gas such as freon is not shown, the lubricating oil O is shown in the lower part of the closed container 10. The discharge pipe 17 through which the heat medium gas is sent out by the compressor P is provided at the upper part of the closed casing 10. The lid 16 of the closed container 10 has a cluster 16 hermetically sealed with glass to electrically insulate and support the conductive pins 16A, 16B, and 16C in a metal ring.
Is airtightly fixed.

In FIG. 5, a protector 30 has a mechanism in which a movable contact is driven by a thermally responsive body such as a bimetal in a metal sealed outer case 31, and a fixed contact paired with the movable contact is provided. The outer casing 31 serving as one of the terminals opens and closes an electric circuit between the outer casing 31 and a terminal pin 32 fixed by an electrical insulating material. Is fixed by a method such as welding. Lead wire is connected to terminal pin 32 at the other end.
13 is connected, and the other end of the lead wire 13 is connected to a common end which collectively connects one end of each of a main winding and an auxiliary winding of the motor. Lead 14 for other receptacles 14A and 15A
And 15 are respectively connected, and the other ends thereof are connected to the other end of the main winding and the other end of the auxiliary winding. Receptacle 13A ・ 1
4A and 15A are housed in a socket 20 made of an electrically insulating material such as phenol resin, and are provided with partition walls 22 and 23 which are electrically insulated from each other. A through-hole (not shown) is provided on the surface of the socket 20 facing the cluster 16, and the three receptacles 13A, 14A, and 15A can be simultaneously fitted to the conductive pins 16A, 16B, and 16C, respectively, by the socket 20. A power supply (not shown) is connected to the outer end of the closed container of the conductive pin, for example, one of the power supplies is connected to the conductive pin 16A,
The other end of the power supply is connected to conductive pin 16C via conductive pin 16B and a capacitor.

According to this protector, since the position of the protector in the sealed container is determined by fixing the socket to the cluster, the mounting and positioning of the protector are facilitated.

[0006]

Recently, due to the miniaturization of the hermetic electric compressor, the space for mounting the protector on the coil end portion has been narrowed in the prior art, or the protector is tied to the coil end with a thread. There is a problem that the process is troublesome.

In the above-described protector for a hermetic electric compressor, it is necessary to attach the protector and the lead wire to the socket before attaching the protector to the cluster.

[0008]

The protector of the present invention includes a mechanism in which a pair of contacts can be opened and closed by a thermally responsive body such as a bimetal in a metal hermetically sealed outer box. One or more terminal pins are hermetically fixed with an electrically insulating material such as glass to a part of the outer box as the box and the other terminal, and a receptacle described later is fixed to the outer box. In a hermetic electric compressor in which this protector is used, a stator of the electric motor is directly fixed to an inner surface of a sealed container, and a rotor is rotatably supported so as to rotate by a magnetic field of the stator. Are connected to each other, and a heat medium gas such as a freon gas in the closed vessel is sent out from the discharge pipe of the closed vessel to work, and thereafter the heat medium gas is returned to the compressor again. A cluster in which a plurality of conductive pins for connecting the motor windings to an external power supply is sealed in a metal annular body with an insulating material such as glass is provided in the closed container, and one of the conductive pins is provided. The position of the protector in the closed container is determined by fitting the receptacle of the protector into the container.
On the other hand, since the stator of the electric motor has the stator directly fixed to the inner surface of the sealed container, the positions of the main winding and the auxiliary winding which are insulated and wound around the stator are naturally determined. Since the rotor and its windings are also located, the temperature correlation between the protector and the motor windings has a significant relevance and is easy to install and economically sealed to protect the motor windings. A protector for an electric compressor can be obtained.

[0009]

An embodiment of the present invention will be described with reference to the drawings. The same components as those shown in FIGS. 4 and 5 are denoted by the same reference numerals, and description thereof will be omitted. FIG.
FIG. 2 shows a receptacle 36A having a shape to be fitted to a flat tab, which will be described later, which is welded and fixed to the conductive pin of the cluster, and is conductively fixed directly to the outer case of the protector. The conductive pins 16A, 16B and 16C of the cluster 16 have flat tabs 35A, 35B and 35C as shown in FIG.
Are welded. Tab 35A on outer case 31 of protector 30
Is welded to a receptacle 36A having a shape for tightening and fixing. The protector 30 is reliably positioned by fitting and fixing the receptacle 36 to the tab 35A. Receptacles 36B and 36C connected to the lead wires 14 and 15 are fitted and fixed to the tabs 35B and 35C of the remaining conductive pins.
With such a configuration, the protector can be positioned with respect to the conductive pins of the cluster without a socket.

Further, if the lead wires 14 and 15 are prevented from conductively contacting other parts and short-circuiting with each other even when they rotate at the mounting position, etc.
The tab of the conductive terminal connected to 15 may be omitted.

Although the description has been omitted in this embodiment, it goes without saying that the present invention can be similarly applied to a so-called 2-pin protector having an auxiliary heater.

[0012]

According to the protector for a hermetic electric compressor of the present invention described above, one of a plurality of receptacles to be connected to conductive pins of a cluster necessary for supplying power to the electric motor is electrically connected to the outer case of the protector. The protector is fixed and electrically connected by connecting the receptacle to the tab fixed to the conductive pin, and the protector can be positioned and fixed and the electrical connection can be made. In comparison with the small motor, the coil end of the winding is small, so there is no need for extra space to bind the protector as before, and extra materials are omitted. There is an excellent effect that can be done.

[Brief description of the drawings]

FIG. 1 is a diagram showing a state in which a protector according to an embodiment of the present invention is connected to a conductive pin of a cluster.

FIG. 2 is a partial cross-sectional view of the hermetic electric compressor according to the embodiment of the present invention.

FIG. 3 is a diagram showing a part of a cluster attached to a lid part from the inside of a closed container.

FIG. 4 is a longitudinal sectional view of the hermetic electric compressor.

FIG. 5 is a plan view of the socket for accommodating the receptacle, with a part of the outer shell removed.

[Explanation of symbols]

 10: Sealed container 13A / 14A / 15A / 36A / 36B / 36C: Receptacle 16: Cluster 16A / 16B / 16C: Conductive pin 30: Protector 31: Outer box 32: Terminal pin 35A / 35B / 35C: Tab F: Motor fixed Child P: Compressor R: Motor rotor S: Rotary shaft W: Coil end

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shozo Iyoda 3-171-1, Higashiyamamotomachi, Chikusa-ku, Nagoya-shi (56) References JP-B Hei 7-67256 (JP, B2)

Claims (1)

(57) [Claims] 1. A hermetic electric compressor in which a stator of an electric motor is fixed to an inner surface of a sealed container, a rotor is supported at the center of the stator, and the compressor is connected so that the compressor can be operated by rotation of the rotor. the cluster formed by several sealing the conductive pins for connection on the closed container to the motor windings to an external power source is hermetically fixed to, among the conductive pins of the cluster, at least below proteinase
The tab terminal is fixed to one of the terminals to which the connector is connected , and two of the conductive pins are each connected to a lead wire.
One end of each of the main winding and the auxiliary winding of the motive is connected to one end of a metal enclosure having good heat conductivity and having one or more terminal pins electrically insulated from the outer enclosure. each of the other main winding and an auxiliary winding the thermally responsive shape protector to the other terminal of the motor winding having a terminal
The said outer box making is connected via the end and the lead wire has a receptacle that is connected to one of the conductive pins of the cluster, the tab receptacle of the protector is fixed to the conductive pins of the cluster The protector is easily fitted to the terminal so that heat exchange with the refrigerant gas is good.
A protector for a hermetic electric compressor characterized by being securely positioned and fixed.