JPH1089254A - Protector for hermetic motor-driven compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a trouble during mounting of a protector attached directly to the conduction terminal of the glass seal terminal of a hermetic motor-driven compressor through a tub terminal and a receptacle. SOLUTION: A protector 11 is formed such that a thermally-actuated switch is integrally held at a holder 13 made of electric insulation. A receptacle 14 and a connection terminal 15 are securely held at the holder 13 and respectively connected to the thermally-actuated switch. One end of the receptacle 14 is inserted in and held at the connection terminal holding part 13A of the holder 13. An introduction part 13J in a shape spreading toward the opening end side to introduce the tub terminal in an insert part is formed in an opening part on the side wherein a tub terminal corresponding to a connection terminal holding part 13A is inserted. Since the tip of the tub terminal is introduced to an insertion part 13K through inclination of the introduction part, a mounting work is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protector used in a hermetic electric compressor, and more particularly to a protector which is directly attached to a conductive terminal of a glass sealed terminal of an electric compressor using a tab terminal and a receptacle. The purpose is to eliminate problems during installation.

[0002]

2. Description of the Related Art Conventionally, various heat-responsive switches have been used to protect the hermetic electric compressor from overheating due to overload or the like. Among these, hermetic electric compressors have been used because of their good heat exchange relationship with electric motors and refrigerants. Some use a thermally responsive switch mounted in a sealed housing of a compressor. The thermal responsive switch may be mounted on a coil of an electric motor as shown in a conventional example in Japanese Utility Model Publication No.
As disclosed in Japanese Patent Publication No. 183, "Overload protection device for hermetic compressor", there is an apparatus mounted inside a container by an elastic body.

[0003] In the case where the protector is tied to the coil with a tying string or the like, there is a problem that the mounting work is not easy and it takes much time. On the other hand, the overload protection device disclosed in Japanese Utility Model Application Laid-Open No. 60-95183 is attached to the inside of the sealed housing by an elastic body, so that the work of mounting the overload protection device becomes easy. It is necessary to install the parts for mounting the motor, and to consider the extra space in the sealed housing of the electric compressor, because a sufficient insulation distance is required between the sealed housing and the motor winding. , The housing needs to be extra large.

On the other hand, in Japanese Patent Application Laid-Open Nos. 62-296439 and 63-28246, "Protectors for Hermetic Electric Compressors", connection terminals such as tabs and receptacles are fixed to the protector. The case where the protector is housed in a socket or fixed to the outside of the socket and the connection terminal is directly attached to a pin of a glass sealed terminal of a sealed housing is shown.

However, in the case where the connection terminal fixed to the protector is directly attached to the glass sealed terminal of the sealed housing as described above, since the protector is easily mounted and the mounting position is minimized, the electric compressor is not used. It is not necessary to consider the extra space in the sealed housing or make the housing extra large.However, due to vibration during operation of the electric compressor, a heavy load is applied to the fixed part between the protector and the connection terminal due to twisting or bending. Thus, there is a problem that the conventional method cannot always provide a sufficient strength.

Accordingly, the present applicant has disclosed in Japanese Patent Application Laid-Open No. Hei 7-91375 that the protector body is integrated with a box-shaped holder made of an electric insulator, and the fixing portion between the protector body and the connection terminal is cured by a filler such as resin. , Proposed a protector to prevent external force. Also, JP-A-7-24
No. 1061 discloses that the protector body is integrated with a box-shaped holder made of an electrical insulator, and the connection terminal is previously inserted into the holder so that the force received by the connection terminal at one end is not transmitted to the other end. We proposed a protector that was held and fixed. According to these protectors, it is possible to eliminate the influence of an external force on the fixing portion between the protector body and the connection terminal, which is a problem in the conventional protector.

[0007]

An example of this protector and its problems will be described with reference to FIGS. In a protector 101 shown in FIG. 8, one terminal 103 is held and fixed to a box-shaped holder 102 formed of resin or the like by the insert molding described above. The other terminal, the receptacle 104, is connected to the terminal holding portion 1 of the holder 102.
02A is slightly inserted into the holder 102A and is elastically fixed to the holder 102.

Although the description of the structure of the protector body 110 is omitted, the protector body 110 has a well-known structure as disclosed in, for example, JP-A-2-227928 and JP-A-5-36335, and is made of metal. Has an opening and closing mechanism using a bimetal or the like in the closed container. The protector body 110 is integrally held and fixed to the holder 102 by fixing the conductive terminal pins 111A and 111B to the terminals 103 and 104 by welding or the like.

This protector 101 is attached to a glass sealed terminal 121 of a hermetic electric compressor.
A tab terminal 122 fixed to a predetermined terminal pin 121A of the glass sealed terminal 121 is fitted into the receptacle 104, and is securely attached to a predetermined stop position electrically and mechanically by elastic force. The terminal 103 is connected to a connection terminal such as a receptacle (not shown) fixed to an end of a lead wire from which one end of the motor winding is drawn.

Here, usually, the receptacle 1 of the protector
When the tab terminal 122 of the glass sealed terminal is fitted into its normal position with respect to the terminal holder 04, the terminal holding part 102 with a receptacle is fitted.
A is extended and positioned within the inner wall of A and mounted as shown in FIG. However, among the glass sealed terminals, there is a type in which the diameter of the terminal pin is small as shown in FIG. 9, and when the protector 101 is used in common for both, a terminal pin 123A having a small diameter like the glass terminal 123 is not used. Since the degree of allowance of the terminal holding portion 102A increases, the tab terminal 122 is forcibly pushed in by being tilted from a regular position, and the tab terminal may be rarely inserted in an incorrect position as shown in FIG. There was a nature.

[0011]

SUMMARY OF THE INVENTION Accordingly, in a protector for a hermetic electric compressor according to the present invention, at least one receptacle having one end connected to a thermally responsive switch is held and fixed to a holder, and one of the receptacles is It is directly connected to the tab terminal conductively fixed to the conductive terminal of the glass sealed terminal of the hermetic electric compressor, and when inserting the tab terminal of the glass sealed terminal into this receptacle, the tab terminal is inserted at a position other than the regular position The holder is provided with an erroneous insertion prevention member for preventing the situation, and an introduction portion having a shape spread to the open end side is provided around the tab terminal insertion portion to guide the tab terminal to the tab terminal insertion portion. It is characterized by having.

[0012]

Embodiments will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a hermetic electric compressor to which a protector for an hermetic electric compressor (hereinafter referred to as a protector) of the present invention is attached. FIG. 5 is a partially enlarged view of an AA cross section of the hermetic electric compressor. The hermetic electric compressor 1 constitutes a hermetic housing (hereinafter simply referred to as a housing) including a lid 2 and a lower housing container 3, and a motor 4 and a compressor 5 having a known structure are housed and fixed in the housing. ing. A suction pipe 6 for introducing a refrigerant sent from a heat exchanger (not shown) to the compressor 5 is connected through the housing, and the refrigerant compressed by the compressor 5 is discharged into the housing to be driven by the electric motor. Flows from the discharge pipe 7 to the heat exchanger again. A part of the housing, in the embodiment, a lid 2 is provided with a through-hole, in which a glass sealed terminal 8 for connecting the electric motor 4 inside the housing to an external power supply is hermetically fixed by welding or the like. I have. A lubricating oil 9 for the electric motor 4 and the compressor 5 is sealed in the housing.

In the embodiment, the glass sealed terminal 8 has three conductive terminals 8A, 8B, 8C, and each of the conductive terminals is air-tightly fixed with an electrically insulating material such as glass.
Tab terminals for connection are attached to the inside of the housing for each conductive terminal, and two of them, 8B and 8B, are provided.
One of a plurality of lead wires 10 from the windings of the motor is connected to C. A protector 11 is directly fixed to a tab terminal of the conductive terminal 8A by a receptacle serving as a connection terminal, and the other one of the lead wires 10 from the electric compressor is connected via the protector 11.

Next, the protector 11 will be described with reference to FIGS.
This will be described with reference to FIG. FIG. 2 is a plan view of the protector 11, FIG. 3 is a plan view seen from the opposite side, and FIG.
FIG. The protector 11 has a thermally responsive switch 12 having a hermetically sealed metal container having a well-known structure as shown in FIG. 6 housed and fixed in an electrically insulating holder 13. As described above, this thermally responsive switch 12 is disclosed in, for example, Japanese Patent Application Laid-Open No.
It has a well-known structure using a thermally responsive element such as a bimetal disclosed in Japanese Unexamined Patent Publication (KOKAI) No. HEI 9-86.

The lead terminals 12A and 12B are hermetically fixed to the thermally responsive switch 12 by an electrically insulating sealing material 12C such as glass or ceramics. Connection terminals 14 and 15 for connection with the above-mentioned glass sealed terminal 8 and a lead wire 10 from an electric motor are conductively connected and fixed to each lead terminal by welding or the like. In this embodiment, the connection terminal 14 is a receptacle directly inserted and fixed in the tab terminal fixed to the conductive terminal 8A of the glass sealed terminal, and the connection terminal 15 is one of the lead wires 10 from the electric motor as described above. Connected to.

Holder 1 molded of synthetic resin such as PPS
Reference numeral 3 denotes a box shape having substantially one side wall, one of the connection terminals 15 is fixed in advance by insert molding, and both ends are exposed. This connection terminal 1
The reference numeral 5 denotes a tab terminal in the embodiment, but the shape is not limited to this, and various modifications can be made by a method of treating the end of the lead wire 10 or connecting and fixing. The holder 13 is provided with a connection terminal holding portion 13A for fixing the receptacle 14, and the tip of the receptacle 14 is inserted and fixed. In the embodiment, a part of the upper part of the wall 13B of the connection terminal holding part 13A in FIG.
Is slightly thicker than the bending width of the receptacle 14.
Is inserted into a predetermined position, so that the shoulder 14B of the terminal elastically crosses over the step 13C and is snapped back and locked, so that the receptacle 14 is held and fixed to the holder 13.

As shown in FIGS. 2, 3 and 6, lead terminal pins 12A and 12B of the thermally responsive switch 12 are fixed to the ends of the receptacle 14 and the connection terminal 15 located inside the holder 13 by welding. Welding portions 14C and 15A are provided. A through hole 13D for inserting a welding electrode is formed at a position corresponding to each of the welded portions of the holder 13.

The thermal responsive switch 12 is housed in a housing 13E of a holder 13 as shown in FIGS.
After being positioned by the contact portion 13G, the lead terminal pins 12A and 12B are welded to the receptacle 14 and the connection terminal 15 which are fixed to the holder 13 in advance and the welding portions 14C and 1C.
It is fixed to the holder 13 by welding to 5A. In this welding, one of the welding electrodes is brought into contact with the lead terminal pin 12A or 12B from the upper side of the sectional view shown in FIG. 4, and the other electrode is inserted through the through hole 13D from the lower side in FIG. After being brought into contact with the lower surface of 14C or 15A, electric resistance welding is performed by applying a predetermined pressure. In this embodiment, an insulating material such as an adhesive or resin is applied so as to cover the sealing material 12C in order to increase the dielectric strength between the lead terminal pins of the thermally responsive switch 12 and the metal hermetic container. The insulation distance between the lead terminal pin and the metal hermetic container is substantially increased by providing an insulating member 16 formed by melting or hardening a pellet-shaped insulator, but the insulation withstand voltage performance is sufficient. You may omit this.

The attachment of the protector 11 to the hermetic electric compressor will be described.
Tab terminals for connection are attached to the inside of the housing at the conductive terminals 8A, 8B and 8C of the glass sealed terminal 8 of the electric compressor 1 shown in FIG. Two of these, 8B, 8
One of a plurality of lead wires 10 from the windings of the motor is connected to C by inserting a receptacle attached to the tip of the lead wire into a tab terminal. Here, as for the conductive terminals 8B and 8C, connection by terminals other than the tab terminal may be used such as fixing the receptacle terminal to the conductive terminal side, and lead wires and motor windings are directly fixed without using the terminals. May be.

A tab terminal 9 fixed to the conductive terminal 8A
By inserting the receptacle 14 which is one connection terminal of the protector 11 into A, the connection and fixing of the protector 11 to the glass sealed terminal 8 are completed. Also protector 1
One of the lead wires 10 from the winding of the electric motor is connected and fixed to one other connection terminal 15. As described above, since the mounting operation can be performed only by the terminal inserting operation, the mounting of the protector 11 of the present invention is very easy.

Since the receptacle 14 flexes and deforms when the tab terminal 9A is inserted and elastically holds the tab terminal, a gap is required between the surface of the receptacle 14 inside the connection terminal holding portion 13A of the holder 13. And Therefore, when inserting and fixing the tab terminal 9A of the conductive terminal 8A to the receptacle 14 as described above in the conventional protector when the tab terminal is inserted and mounted, the tab terminal fixed to the conductive terminal 8A is rarely used as shown in FIG. There is a possibility that it is inserted into the connection terminal holding portion 13A while being inclined as shown in FIG.

However, according to the present invention, as shown in FIGS. 3 and 4, the connection terminal holding portion 13A is erroneously inserted on the side where the conductive terminal 8A is inserted so as to cover an unnecessary gap generated on the side of the receptacle 14. A barrier 13H is provided as a blocking member. In the vicinity of the tab terminal insertion portion, there is provided an introduction portion 13J having a shape spread toward the opening end side for guiding the tab terminal to the tab terminal insertion portion 13K, and in this embodiment, an introduction portion including a barrier 13H. 13J is provided to be inclined in the direction of the tab terminal insertion portion 13K. Therefore, when the tab terminal 9A is inserted, the tip of the tab terminal is guided to the insertion portion 13K by this inclination, so that the mounting operation is facilitated, and when the tab terminal 9A is inserted with the inclination, the barrier terminal 13H is inserted. Because of the contact, the tab terminal is not inserted with an incorrect positional relationship. In the present embodiment, the introduction portion 13J is shown as having a slope around the entire circumference of the insertion portion. However, if the introduction portion 13J is formed to have a shape extending toward the opening end, the entire circumference is not necessarily limited. It is not necessary to use an inclined surface. For example, only a surface having the barrier 13H may be an inclined surface, and another surface may be provided vertically.

Since the barrier 13H is provided so as not to come into contact with the receptacle 14, the barrier 13H does not hinder the bending of the receptacle when the tab terminal is inserted. Further, the center of the barrier 13H is hollowed out so that the conductive terminal 8A can be inserted therein, so that the conductive terminal 8A can be inserted into the connection terminal holding portion 13A without any problem in a normal posture. In the embodiment, the connection terminal holding portion 13 serves as an erroneous insertion preventing member.
Although an example in which a barrier 13H is provided on the opening side of A to cover an unnecessary gap generated on the side of the receptacle 14 has been described, the shape of the erroneous insertion preventing member is not limited to this. It goes without saying that there are various shapes such as a protruding member as long as the tab terminal can be prevented from being inserted into a necessary gap.

When the electric compressor is operated, a force such as torsion or bending is applied to the protector 11 from the lead wire or the sealed glass terminal through the receptacle 14 and the connection terminal 15 by the vibration or the like. However, in the present invention, the receptacle 14
Since the bent portion 14A is firmly held and fixed to the wall portion 13B of the holder 13, and the intermediate portion of the connection terminal 15 is fixed to the holder 13 by insert molding, the above-described force such as torsion or bending is applied to the holder. Since it is received as a whole, the force does not concentrate on the welded portion, which is the fixed portion between the connection terminal and the thermally responsive switch, and deformation and breakage of the fixed portion can be prevented. Further, since the connection portion of the receptacle 14 with the glass sealed terminal is held by the connection terminal holding portion 13A, the bending and torsional movements are restricted, so that deformation and breakage can be prevented.

Since almost the entire metal container of the thermally responsive switch 12 is open to the surroundings, the refrigerant in the hermetic electric compressor flows directly around the thermally responsive switch and the protector 11 controls the temperature of the refrigerant. You can quickly follow changes.
Here, the surface of the metal container of the thermally responsive switch 12 is not insulated, but the closest parts such as the lid 2 of the hermetic electric compressor 1 and the edge of the glass sealed terminal 8 are made of insulating material. Since a certain holder 13 is interposed, a substantial insulation distance can be taken, and since there is a sufficient distance from other parts such as the lower housing 3, the insulation does not pose a problem.

Although the embodiment has been described by way of example of a thermally responsive switch having two lead terminal pins, the type of the thermally responsive switch is a metal hermetic container and an insulating material penetrating through the hermetic container. The type of the embodiment is not limited as long as it has at least one fixed lead terminal pin. For example, the other of the connection terminals may be conductively fixed to a metal sealed container of a thermally responsive switch. The thermoresponsive switch may be fixed to the holder.

[0027]

According to the protector for a hermetic electric compressor of the present invention, a barrier is provided on the connection terminal holding portion on the side where the conductive terminal is inserted, and the tab terminal is guided to the tab terminal insertion portion around the tab terminal insertion portion. The leading end of the tab terminal is guided to the tab terminal inserting portion by the leading portion when the tab terminal fixed to the conductive terminal is inserted by providing the introducing portion having a shape spread to the opening end side in order to perform the insertion. The installation work becomes easy, and the trouble that the tab terminal is inserted into the receptacle of the protector while being tilted is reliably prevented,
The protector is mounted on the glass sealed terminal in a proper posture.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a hermetic electric compressor using a protector of the present invention.

FIG. 2 is a plan view of one embodiment of the protector of the present invention.

FIG. 3 is a bottom view of the protector of FIG. 2;

FIG. 4 is a sectional view of the protector in FIG.

FIG. 5 is an enlarged view of an AA cross section of the hermetic electric compressor of FIG. 1;

FIG. 6 is an exploded perspective view of the protector of FIG. 2;

FIG. 7 is a perspective view of the protector of FIG. 2;

FIG. 8 is a plan view showing an attached state of a conventional protector.

FIG. 9 is a plan view showing a problem in mounting a conventional protector.

[Explanation of symbols]

 1: Hermetic electric compressor 8: Glass sealed terminal 11: Protector 12: Thermoresponsive switch 12A, 12B: Lead terminal pin 13: Holder 13A: Connection terminal holding portion 13H: Barrier 13J: Introducing portion (around the tab terminal insertion portion) 13K: Tab terminal insertion part 14: Receptacle (connection terminal) 15: Connection terminal

Claims (1)

[Claims] 1. A thermoresponsive switch having a metal hermetically sealed container, at least one lead terminal pin insulated and fixed through the hermetically sealed container, and a box-shaped holder made of an electrical insulator. At least one receptacle is connected and fixed to the holder, one end of which is connected to the thermally responsive switch and the other end of which is electrically connected to the conductive terminal of a glass sealed terminal of the hermetically sealed electric compressor described below. The thermoresponsive switch is fixed to the holder by conductively fixing the thermoresponsive switch and the receptacle, and is fixed to the holder by being housed in the recess of the holder. Is directly connected to the tab terminal that is conductively fixed to the conductive terminal of the glass sealed terminal.When inserting the tab terminal of the glass sealed terminal into this receptacle, the tab terminal is out of the proper position. The holder is provided with an erroneous insertion preventing member for preventing insertion from the outside, and the tab terminal insertion portion has a shape spread to the open end side to guide the tab terminal to the tab terminal insertion portion. A protector for a hermetic electric compressor, wherein an introduction portion is provided.