JPS60113620A - Protecting relay of motor driven compressor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a protection relay for an electric compressor used as an electrical component of an electric compressor, and particularly relates to a protection relay for an electric motor coupled to a terminal of a compressor case. Concerning compressor protection relays.

[Technical background of the invention and its problems]

An electric compressor is incorporated in a refrigeration cycle for indoor cooling/heating air conditioners and refrigeration, and the refrigeration cycle is operated by driving this compressor.

In the electric compressor, as shown in FIG. 1, a single-phase induction motor 2 having a motor main winding 2a and an auxiliary winding 2b is housed in a compressor case 1. The compressor case 1 is provided with the terminal section 3 for energizing the electric motor, and this terminal section 3
A protection relay 4 is attached to the electric compressor as an electrical device. The protective relay 4 includes a motor protector 5 and a positive characteristic thermistor 6, and each terminal 3a of the terminal section 3
.

Three glue receptacles 7 connected to 3 b + 3 c
a.

7b, 7c and four external connection terminals 5a1sb+sc+
8d.

Among the four external connection terminals 8a to 8d, the first external connection terminal 8a is connected to the AC power supply 9 as shown in FIGS.
can be connected to one side of the AC power supply 9, and a second
External connection terminal 8b is connected. Third external connection terminal 8C
is connected to the second external connection terminal 8b by a wire 10 when the single-phase induction motor 2 adopts the resistive phase-split starting method as shown in FIG. When the motor 2 adopts the capacitor starting method as shown in FIG. 3, the third external connection terminal 8
c is connected to the starting capacitor 11. The fourth external connection terminal 8d is connected to the operating capacitor 12.

On the other hand, since single-phase induction motors do not have the ability to self-start, they are equipped with a starting device, and these starting methods include resistance split-phase starting methods and capacitor starting methods.
The optimal starting method is selected according to the A category. When the electric motor 2 is selected to use the resistance split phase starting method, the protective relay 4 also becomes a circuit dedicated to resistance split phase starting, and when the capacitor starting method is selected, the protection relay 4 becomes a circuit dedicated to capacitor starting.

By the way, the conventional protection relay 4 for a dynamic compressor is basically preset in a circuit dedicated to starting a capacitor, as shown in Fig. 3, and the relay 4 equipped with this capacitor starting circuit is connected to a resistor. When adapting to a split-phase starting type motor, connect the inside of the protection relay 4 (the second external connection terminal and the third external connection terminal) by soldering or caulking, and use the resistor split-phase starting circuit shown in No. 29. The meeting is organized.

However, in order to configure the protective relay 4'f applied to the resistance split-phase starting method, the inside of the protective relay 4 must be connected each time by complicated soldering and caulking work, making the wiring work troublesome. It takes up a lot of time. For this reason, it was difficult and rare to make the maintenance system 4 versatile.

[Purpose of the invention]

This invention takes the above-mentioned points into consideration, provides versatility to the protective relay, and can be applied from the resistor split-phase starting method to the capacitor-starting/assisting method motors by a simple and simple disconnection operation.
The purpose is to provide a protection relay for electric compressors.

[Summary of the invention]

In order to achieve the above-mentioned object, the electric compressor protector 1i 1J according to the present invention is equipped with a positive characteristic thermistor and a motor protector, and is connected to the I In the motor protector, the first motor is provided with the motor protector and is connectable to one of the AC power sources.
an external connection terminal and a second terminal connectable to the other of the AC power sources.
It has an external connection terminal, a third external connection terminal, and a fourth external connection terminal connectable to an operating capacitor, and the second and third external connection terminals are connected to each other by a disconnectable connection, The third external connection terminal is configured to be connectable to a starting capacitor, and is configured to be disconnected when the capacitor starting method is adopted.

[Embodiments of the invention]

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

Figure 4 shows a protection relay 20 as an electrical component of an electric compressor.
This is a circuit diagram showing the addition of a motor protector 21 and a positive characteristic thermistor 22 that improves the starting torque of the MFM machine, and three receptacles (sockets) 23a? 23 b +
Z3 c and 4 external connection terminals (Faston Taz) 2
4 a.

It has 24b, 24c + 24d. Each receptacle 23a.

23 b + 23 c are terminals 26 a + 26 b formed in the terminal portion 26 of compressor case b.
+26 c K connected. A daughter phase induction wall 27 is accommodated within the compressor case 6. This electric motor 2
7 is the motor main winding 28a, motor auxiliary winding xb and all
and each winding 28a.

The electric motor 27 is energized by coupling to the motor 28b, and a rotor (not shown) is rotated.

The above-mentioned seeding strip is based on a resistive phase-split starting circuit 9, and the first external connection terminal 24a equipped with the motor protector 21 can be connected to one side of the AC power supply, and the other side can be connected to the first external connection terminal 24a. The second external connection terminal 24b is configured to be connectable.The third external connection terminal 24c is kept free when the motor adopts the resistance split phase starting method shown in FIG. When adopting this method, the starting capacitor 31 can be connected to the starting capacitor 31. In this case, the starting capacitor 31 is connected in series with the motor auxiliary winding 28b.Furthermore, the fourth external connection terminal 24d is connected to the running capacitor 32. This operating capacitor 32 can be connected to
The other side is connected to the other side of the AC power supply 30.

On the other hand, the positive temperature coefficient thermistor 22 disposed inside the ELJ resistor is interposed in the connection connecting the third and fourth external connection terminals 24C224d to each other, and the third external connection terminal 24c is a thin metal plate. The second external connection terminal 24bK is electrically connected to the second external connection terminal 24bK by a cuttable wire 34 consisting of . In this case, the wiring inside the protective relay may be formed of a metal plate, and in that case, the internal wiring can be integrally molded using a single mold in one molding process.

Therefore, when applying the protection relay shown in Fig. 4 to the motor 27 of the resistor phase-split starting system, it is sufficient to set it as is as shown in @Fig. When applied to the protective relay, the connection 34 inside the protective relay may be disconnected. This cutting work is done in No. 1.
Unlike wiring work such as soldering and caulking work, it can be done easily and in a short time.

The actual IJ relay is configured as shown in FIGS. 7 and 8, and includes a motor protector 21, a positive temperature coefficient thermistor 22, and receptacles (sockets) 23a, Z3b,
23c is housed in the main body case 35.

In this stored state, the main case 35 has a cup 9-
36, and this cover 36 is integrally attached to the main body case 35 with rivets or the like.

Therefore, the protection relay is connected to terminals 26a and 26b protruding from the terminal section 26 of the compressor case B.

26c with receptacles 23a, 23b, 23c
is attached by being pushed in, and in this attached state, the four external connection terminals 24a, 24b, 24c, 2
4d is a capacitor 32. <31) so that it can be connected to an AC power source.

Next, the operation of this invention will be explained.

When installing the electric compression type protection relay 20 shown in Fig. 4 as an electrical component of a single-phase induction motor with resistance split phase starting method, the protection relay 20 is set as is as shown in Fig. 5, and this set By later passing through the motor, currents having different phases are obtained between the motor main winding 28a and the motor auxiliary winding ib, which is arranged at an electrical angle of 90° from the main winding 28a, and a rotating magnetic field is generated. It will be done. The electric motor section is activated by this rotating magnetic field, and a rotor (not shown) is rotated. At this time, since a positive temperature coefficient thermistor n is housed in the protection relay, the thermistor 22 improves the starting torque and generates a large starting torque.

When the motor section is started and enters the operating state, the positive temperature coefficient thermistor n is heated and becomes a large resistance, so that no current flows to the motor auxiliary winding +128b side.

In addition, when the protective relay 20 shown in FIG. 4 is applied to a capacitor-starting motor, the second external connection terminal 2 in the protective relay connection part 2 as shown in No. 6R and FIG.
4b and the third external connection terminal 1c is cut.

In this way, the protective relay 20, which is basically used as an electrical component for a resistor-phase-starting motor, can be applied as an electrical component for a capacitor-starting method by simply cutting one part of the protective relay connection. I can do it.

In this case, the starting capacitor 31 is connected in series with the motor auxiliary winding 28b, and by advancing the phase of the current flowing in the motor auxiliary winding 28b with this capacitor 31, a rotating magnetic field is obtained, and single-phase induction The electric motor is activated. In the capacitor-starting single-phase induction motor, the excitation current is compensated by the advancing phase current of the single starting capacitor 31, so the starting current 'α is small and the starting torque is large. For this reason,
For example, it is suitable for electric motors of about 100W to 400W.

〔Effect of the invention〕

As described above, in the protection relay for an electric compressor according to the present invention, it is only necessary to change the starting circuit of the motor, cut and note the connections inside the protection relay, and it is not necessary to solder or scrape as in the conventional case. ;]? Since no wiring work such as welding is required, the starting circuit can be easily changed from a resistor phase-split starting method to a capacitor starting method by a simple process.

In addition, if the six elements inside the protective relay are made of metal plates, the internal wiring can be integrally molded with a single mold.
The wiring structure becomes fili elemental.

[Brief explanation of drawings]

Figure 1 is a circuit diagram showing a conventional electric compression type protection relay.
Figure 2 is a circuit diagram showing an example of using a conventional protective relay as an electrical component with a resistor split-phase startup method, and Figure 3 is a complete circuit diagram showing an example of using a conventional protective relay as an electrical component with a capacitor startup method. Fig. 4 is a circuit diagram showing an embodiment of the protection relay for an electric compressor according to the present invention, and Fig. 5 shows an example in which the protection IJ L/- of the present invention is used as an electrical component of a resistance split phase starting method. Circuit diagram: Figure 6 is a circuit diagram showing an example of the protective relay using the gold capacitor starting method as an electrical component; Figure 7 is a diagram showing how the protective relay is installed in the compressor case of an electric compressor. , Figure 8 is Vl in Figure 7.
It is a figure along the ll-VII line. Add...protective relay, 21...motor protector, 2
2...Positive characteristic thermistor, 23 a + 23 b
+ 23 c... Receptacle, 24a, 24b
, 24c, 2Atl...external connection terminal, δ・
...Compressor case, 26...Terminal part, n...
Single-phase induction sleep motor, 28a...Motor main winding, 4b...
・Motor auxiliary winding, addition...AC power supply, 31...starting capacitor, 32...driving capacitor, 35...
・Body case. Applicant's agent Hisashi Hatano? 51-in I Binding Figure 6 9 Convex

Claims (1)

[Claims] 1. A protection relay for an electric compressor that includes a positive characteristic thermistor and a motor protector and is connected to a terminal section for energizing the motor of a compressor case, which includes the motor protector and is connected to one side of an AC power supply. It has a connectable first external connection terminal, a second external connection terminal connectable to the other of the AC power sources, a third external connection terminal, and a fourth external connection terminal connectable to the operating capacitor, The second and third external connection terminals are connected to each other by a disconnectable connection, and the third external connection terminal is configured to be connectable to a starting capacitor, and when a capacitor starting method is adopted,
A protection relay for an electric compressor, characterized in that the connection is cut. 2. The electric compressor protection relay according to claim 1, wherein the disconnectable connection is made of a thin metal plate, and the connection is disconnected when using a capacitor activation method.