DE112019005039T5 - Test method and test system for a stator - Google Patents

Abstract

In a test method and system according to the present invention, an arranging step (S1), a pressure reducing step (S2), a dipping step (S3) and a testing step (S5) are carried out in this order. In the arranging step (S1), a stator (1) is stored in a test chamber (3c) of a test container (3) in a sealed state. In the pressure reduction step (S2), the pressure in the test chamber (3c) is reduced after the arrangement step (S1). In the immersion step (S3), after the pressure reduction step (S2), a test liquid (17) having electrical conductivity is fed into the test chamber (3c), and the stator (1) is immersed in the test liquid (17). In the test step (S5), after the immersion step (S3), a test for an electrical loss from the stator (1) is carried out by means of the test liquid (17).

Description

Technical area

The present invention relates to a test method and system for a stator.

State of the art

A stator that constitutes a motor and the like includes a coil made of an insulation coated conductive wire. A specific example of the insulation coated conductive wire is an enameled wire made of a conductive copper wire covered with an insulation layer made of enamel. If an invisible defect such as a pin hole or a scratch develops on the insulation layer of the insulation-coated conductive wire, the coil may be short-circuited in an electrically conductive environment, which may cause failure of some essential functions of the motor and the like.

Patent Document 1 discloses a vacuum heating chamber which can be used for testing such a stator. In order to check acceptability of the stator using the vacuum heating chamber, a test container including a test chamber is prepared, and a test liquid which is electrically conductive is supplied into the test chamber. Patent Document 1 uses water as the test liquid. The stator is placed in the test chamber and immersed in the test liquid. Thereafter, a pressure in the test chamber is reduced to remove air existing in the stator including the coil as air bubbles. Then, electrical leakage from the stator through the inspection liquid is checked by measuring an insulation resistance or an amount of leakage current.

Citation list

Patent document

Patent Document 1: Japanese Utility Model Application Laid-Open No. S60-15658

Summary of the invention

Technical task

The stator is used, for example, in a motor section of an electric compressor for a vehicle. In this case, the stator may include a terminal that is electrically connected to a lead made of the insulation-coated conductive wire that extends from the coil and a group block that receives the terminal, in addition to the coil and a core . When such a stator is used in the electric compressor, the group block is immersed in a mixed liquid of a refrigerator oil and a liquid-phase refrigerant in addition to the coil. Therefore, as a measure for preventing the electrical leakage from the stator in this state, the group block needs to be sealed.

However, when the stator is completely sealed, a pressure difference is generated between an inside and an outside of the group block in use, raising concerns about durability of the group block and ultimately, for example, the electric compressor for a vehicle. For this reason, such a stator requires a uniformly pressurized passage that balances the pressures inside and outside the group block.

On the other hand, when the above-described conventional test method is used to test the acceptability of the stator including the group block connected to the uniformly pressurized passage, the pressure in the test chamber is reduced after the group block is immersed in the test liquid. In this case, the uniformly pressurized passage has an elongated shape, so that an insulating effect of the group block does not deteriorate. Thus, without sufficient time to reduce the pressure, the test liquid does not penetrate into the group block and the uniformly pressurized passage to the core. In addition, the acceptability of the stator is not carefully checked if air remains in the group block.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a test method and a test system for a stator by which acceptability of the stator is checked highly accurately in a short and stable period of time even in a case in which wherein the stator comprises a group block and a uniformly pressurized passage is formed in the stator.

Solution of the task

A stator test method according to the present invention is a stator test method for testing electrical loss from the stator by a test liquid that is electrically conductive by immersing the stator in the test liquid in a test chamber. The stator includes a coil that includes an insulation coated conductive wire.

• einen Anordnungsschritt, bei dem der Stator in der Prüfkammer in einem abgedichteten Zustand angeordnet wird;
• einen Druckreduktionsschritt, bei dem ein Druck in der Prüfkammer nach dem Anordnungsschritt reduziert wird;
• einen Tauchschritt, bei dem der Stator nach dem Druckreduktionsschritt in die Prüfflüssigkeit getaucht wird; sowie
• einen Prüfschritt, bei dem der elektrische Verlust aus dem Stator durch die Prüfflüssigkeit nach dem Tauchschritt geprüft wird.

The stator includes the coil, a lead made of the insulation coated conductive wire extending from the coil, a terminal electrically connected to the lead, a group block that receives the terminal, and a uniformly pressurized passage, which provides a connection between an inside and an outside of the group block. The test procedure includes:

• an arranging step in which the stator is arranged in the test chamber in a sealed state;
• a pressure reducing step in which a pressure in the test chamber is reduced after the arranging step;
• a dipping step in which the stator is dipped in the test liquid after the pressure reducing step; as
• a test step in which the electrical loss from the stator is checked by the test liquid after the immersion step.

According to the test method for the stator of the present invention, the stator includes the terminal and the group block in addition to the coil. The stator further comprises the uniformly pressurized passage, which provides a connection between the inside and the outside of the group block to an extent at which the insulation effect does not deteriorate.

When the test method of the present invention is used to test an acceptability of the stator, the pressure in the test chamber is reduced in a state in which the test liquid is not present in the test chamber in which the stator is arranged, because the pressure reducing step after Arrangement step is carried out. Therefore, the pressures in the group block and the uniformly pressurized passage are also quickly reduced. Then, by performing the immersion step, the test liquid quickly penetrates into the group block and the uniformly pressurized passage to the core by simply adding the test liquid.

Therefore, in the checking step, the acceptability of not only the coil but also the insulating effect of a sealed portion of the unitary pressurized passage and the group block is carefully checked.

As a result, according to the stator inspection method of the present invention, the acceptability of the stator is highly accurately checked in a short and stable period of time even in a case where the stator includes the group block and the uniformly pressurized passage is formed in the stator.

In the stator, the group block and finally, for example, the electric compressor for a vehicle offer long durability because the uniformly pressurized passage reduces the pressure difference between the inside and the outside of the group block.

Preferably, the stator may comprise a tube extending through the group block and receiving the conduit, a gap being sealed between the tube and the group block, and the uniformly pressurized passage formed between the tube and the conduit. Such a pipe forms the uniformly pressurized passage while maintaining a great insulating effect.

The pipe can preferably be designed in such a way that a space between the pipe and the line is narrowed. In this case, the insulating effect of the uniformly pressurized passage formed in the space between the pipe and the conduit is improved.

• einen Prüfbehälter, der eine Prüfkammer hat, in der der Stator in einem abgedichteten Zustand anordenbar ist und in eine Prüfflüssigkeit tauchbar ist, die elektrisch leitfähig ist;
• eine Druckreduktionseinheit, die mit der Prüfkammer durch einen Druckreduktionsdurchlass verbunden ist und eingerichtet ist, einen Druck in der Prüfkammer zu reduzieren;
• einen Flüssigkeitstank, der mit der Prüfkammer durch einen Flüssigkeitszuführdurchlass verbunden ist und die Prüfflüssigkeit speichert;
• ein erstes Öffnungs-/Schließventil, das eingerichtet ist, den Druckreduktionsdurchlass zu öffnen und zu schließen;
• ein zweites Öffnungs-/Schließventil, das eingerichtet ist, den Flüssigkeitszuführdurchlass zu öffnen und zu schließen;
• eine Steuerungseinheit, die eingerichtet ist, mindestens das erste Öffnungs-/Schließventil und das zweite Öffnungs-/Schließventil zu steuern; und
• eine Prüfvorrichtung, die eingerichtet ist, einen elektrischen Verlust aus dem Stator durch die Prüfflüssigkeit zu prüfen.

Also, a test system for a stator according to the present invention is a test system for a stator that includes a coil including an insulation-coated conductive wire, a lead made of the insulation-coated conductive wire extending from the coil, a terminal, which is electrically connected to the line, a group block that receives the connector, and a uniformly pressurized passage that provides a connection between an inside and an outside of the group block. The test system includes:

• a test container which has a test chamber in which the stator can be arranged in a sealed state and can be immersed in a test liquid which is electrically conductive;
• a pressure reduction unit connected to the test chamber through a pressure reduction passage and configured to reduce a pressure in the test chamber;
• a liquid tank that is connected to the test chamber through a liquid supply passage and stores the test liquid;
• a first opening / closing valve configured to open and close the pressure reduction passage;
• a second opening / closing valve configured to open and close the liquid supply passage;
• a control unit configured to control at least the first opening / closing valve and the second opening / closing valve; and
• a test device which is configured to test an electrical loss from the stator by the test liquid.

The control unit closes the second opening / closing valve and opens the first opening / closing valve in a state in which the test liquid does not exist in the test chamber in which the stator is arranged.

The control unit closes the first opening / closing valve and opens the second opening / closing valve when a predetermined degree of vacuum is reached in the test chamber.

The control unit closes the second opening / closing valve and activates the test device when the stator in the inspection chamber is immersed in the test liquid.

According to the test system of the present invention, the control unit closes the second open / close valve and opens the first open / close valve in a state where the test liquid does not exist in the test chamber in which the stator is disposed. The test liquid is not supplied from the liquid tank to the test chamber, and pressure in the test chamber is reduced by the pressure reduction unit. This quickly reduces the pressures in the group block and the uniformly pressurized passage as well.

When the predetermined degree of vacuum is reached in the test chamber, the control unit closes the first opening / closing valve and opens the second opening / closing valve. This enables the predetermined degree of vacuum to be maintained in the test chamber and the test liquid to be supplied from the liquid tank, so that the test liquid quickly penetrates the group block and the uniformly pressurized passage to the core.

Then, when the stator is immersed in the test liquid in the test chamber, the control unit closes the second opening / closing valve and activates the test device. This stops supplying the test liquid to the test chamber, and an acceptability of the stator is checked. At this time, it can also be determined whether or not a portion (for example, the coil) other than the group block and the uniformly pressurized passage is short-circuited, and thus the acceptability of the stator can be accurately checked.

As a result, according to the stator inspection system of the present invention, the acceptability of the stator is highly accurately checked in a short and stable period of time even in a case where the stator includes the group block and the uniformly pressurized passage is formed in the stator.

The stator can form part of a motor that can be mounted on an electric compressor. A part of the test container can form a motor housing of the electric compressor for receiving the motor. The motor housing may preferably include an electrical connection pin extending through the motor housing and having one end that is electrically connected to the terminal and the other end that is electrically connected to the test device, and a sealing element that has a gap between the electrical connection pin and the motor housing seals. In this case, electrical connection between the terminal and the test device is easy, and short-circuiting at a portion of the electrical connection pin that is in contact with the test liquid is easily prevented.

According to the testing method for the stator of the present invention, an air discharging step in which air in the testing chamber is discharged to an environment may preferably be performed between the dipping step and the testing step.

According to the test system for the stator of the present invention, the test system may preferably include an air discharge valve configured to discharge the air in the test chamber to the outside. Then, after the control unit has closed the second opening / closing valve when the stator is immersed in the test liquid in the test chamber, the control unit can preferably cause the air outlet valve to discharge the air in the test chamber to the outside and activate the test device .

In this case, air bubbles that are only slightly contained in the test liquid under the reduced pressure are removed from the test liquid by exposing the test liquid to the ambient pressure. This ensures a higher test accuracy than in a case in which the test step is carried out under the reduced pressure.

Advantageous Effects of the Invention

According to the inspection method and system for the stator of the present invention, the acceptability of the stator becomes highly accurate in one short and stable period of time is also checked in a case where the stator includes the group block and the uniformly pressurized passage is formed in the stator.

Figure list

• 1 Figure 13 is an operational diagram of a test method and system in accordance with an embodiment of the present invention.
• 2 Fig. 13 is a schematic sectional view of the inspection system at an arranging step according to the embodiment.
• 3 Fig. 13 is a sectional view of a motor case and surrounding parts related to the inspection system according to the embodiment.
• 4th Fig. 13 is a partially enlarged sectional view of a group block and surrounding parts related to the test system according to the embodiment.
• 5 Fig. 3 is a schematic diagram of a stator and a test apparatus.
• 6th Fig. 13 is a schematic sectional view of the inspection system in a pressure reducing step according to the embodiment.
• 7th Fig. 13 is a schematic sectional view of the inspection system at a dipping step, an air exhaust step and a testing step according to the embodiment.
• 8th Fig. 13 is a graph of change characteristics between time and insulation resistances in tests according to the test system of the embodiment and a test system of a comparative example.

Description of embodiments

An embodiment of the present invention will now be described with reference to the accompanying drawings. In the embodiment, an acceptability of a stator 1 used in an engine section of an electric compressor for a vehicle (see 2 , 3 , 6th and 7th ).

As in 1 shown, according to a test method of the embodiment, an arranging step S1 , a pressure reduction step S2 , one dive step S3 , an air exhaust step S4 as well as a test step S5 carried out. Here, a test system of the embodiment is used. The test system comprises a test container 3 , a vacuum pump 5 , a liquid tank 7th , a first opening / closing valve 9 , a second opening / closing valve 16 , a control unit 13th as well as a test device 15th .

As in the 2 and 3 is shown, the test container has 3 a motor housing 3a and a cover body 3b. The motor housing 3a forms part of a shell of the electric compressor for a vehicle. The motor housing 3a has a bottomed cylindrical shape and has an opening 3d at its upper portion. The stator 1 is fixed in a motor chamber 3d on the motor housing 3a by means of a shrink fit. The motor housing 3a includes a suction port 3e at a lower end of a side wall of the motor housing 3a for communication between an outside of the motor housing 3a and the motor chamber 3c provide. The engine chamber 3c corresponds to a test chamber of the present invention.

The lid body 3b is made of a resin. The lid body 3b is inserted into the opening 3d of the motor housing 3a from above to close the opening 3d. Thus is the motor chamber 3c sealable. A test liquid 17th , in the 2 shown is from the liquid tank 7th into the motor chamber 3c fed so that the stator 1 into the test liquid 17th is submersible. As the test liquid 17th For example, a water controlled to have a constant electrical conductivity, a liquid mixture of a fluorine-based inert liquid and a conductive liquid, a salt water, or the like can be used.

The lid body 3b includes a liquid supply passage 8b , a pressure reduction passage 19b and an air outlet passage 20 communicating with the interior of the motor chamber 3c are connected. The liquid supply passage 8b is with a liquid supply passage 8a connectable to the liquid tank 7th connected is. The pressure reduction passage 19b is with the pressure reducing passage 19a connectable to the vacuum pump 5 connected is. The air outlet passage 20 provides communication between the motor chamber 3c and the environment via an air outlet valve 21 ready, which is arranged in between. The air outlet valve 21 is configured to open and close the air outlet passage 20. The lid body 3b comprises a pressure sensor 25 which is configured to measure a pressure in the motor chamber 3c capture.

As in the 3 and 4th shown comprises the stator 1 a coil 1a , a core 1b , a group block 1c , Pipes 1d , Connections 1e , a sealing element 1f and sealing elements 1g.

The sink 1a is made of an enamelled wire made from a copper wire covered with an insulating layer made of enamel. The core 1b includes a plurality of slots. Each slot takes the spool 1a on. The group block 1c is in the motor housing 3a held. The group block 1c is made of a resin and includes three passages of the group block 1c .

As in 4th shown are three sets of two lines 1i of the enameled wires extending from the coil 1a extend into the appropriate tubes 1d made of resin at positions immediately in front of the group block 1c used. The group block 1c takes connections 1e on. The pipes 1d are through the connections 1e in the passages or in the group block 1c held, and taking copper wires from each set of leads 1i in the corresponding pipe 1d with the corresponding connection 1e are electrically connected. Each of the tubes 1d extends through the group block 1c . The pipes 1d are bundled and twisted, leaving a space between each set of wires 1i and the corresponding pipe 1d is narrowed, which is not shown.

Electrical connection pins 29 are in the respective terminals 1e used. The electrical connection pins 29 are connectable to an inverter for driving the electrical compressor outside the motor housing 3a.

A gap between the sealing element 1f and the group block 1c is sealed with a resin sealant. As a result, the stator includes 1 uniformly pressurized passages that are only in spaces between the pipes 1d or the sets of lines 1i are trained. The uniformly pressurized passages provide a connection between an inside and an outside of the group block 1c ready. The seal members 1g are respectively inserted into the through holes 3f of the motor housing 3a, and the three electrical connection pins 29 are respectively inserted through the through holes 3f so that the electrical connection pins 29 are sealed. Each of the sealing elements 1 _g seals a gap between the motor housing 3 a and the corresponding electrical connection pin 29.

As in 2 shown is the test container 3 connectable to a filter unit 12 through a first return passage 10a which is connected to the suction opening 3e of the motor housing 3a. The filter unit 12 is with the liquid tank 7th connected by a second return passage 10b. The first return passage 10a and the second return passage 10b include a liquid supply pump, which is not shown.

The liquid tank 7th saves the test liquid 17th coming out of the engine chamber 3c of the test container 3 running back, in a vacuum. The liquid tank 7th comprises a heating means 7a for controlling a temperature of the test liquid 17th . The liquid supply passages 8a and 8b provide a connection between a bottom portion of the liquid tank 7th and the motor chamber 3c ready. The liquid supply passage 8a includes the second opening / closing valve 16 . The second opening / closing valve 16 is configured to be the liquid supply passage 8a to open and close.

The first return passage 10a includes an electromagnetic opening / closing unit 14 that opens the suction port 3e to communicate between the motor chamber 3c and to provide an inside of the first return passage 10a, and the suction port 3e closes to the motor chamber 3c to seal.

The test system of the embodiment also includes the vacuum pump 5 that came with the test container 3 through the pressure reduction ports 19a and 19b is connectable. The pressure reduction passage 19a includes the first opening / closing valve 9 . The first open / close valve 9 is set up the pressure reduction passage 19a to open and close. The vacuum pump 5 corresponds to a pressure reducing unit serving as a pressure changing unit and wherein the pressure reducing passages 19a and 19b Pressure change passages correspond. The vacuum pump 5 is set up the pressure in the motor chamber 3c to reduce to at least a predetermined degree of vacuum when the first open / close valve 9 is open.

As in 5 shown is the testing device 15th electrically connected to a connection terminal 27 connected to the motor housing 3a and a connection terminal 31 connected to one of the electrical connection pins 29 connected to the stator 1 are connected. The sink 1a is a trouser-piece connected three-phase coil. Thus, the connection port 31 is with one of the ports 1e in the group block 1c electrically connected, as in 4th is shown. The testing device 15th comprises a resistance measuring means 15a and a correction circuit 15b who is in 5 is shown.

The correction circuit 15b is arranged between a node P1 near the resistance measuring means 15a and a node P2 near the connection terminal 27. A conductive wire L1, which includes a resistor R1, is connected to the node P1. Conductive wires L2 to L4 arranged in parallel with each other are connected to one end of the conductive wire L1 near the node P2 with respect to the resistor R1. The conductive wire L2 includes a resistor R2. The conductive wire L3 includes a capacitor C1 on one side of the conductive wire L3 near the resistor R1 as well a resistor R3 on one side of the conductive wire L3 near the node P2. The conductive wire L4 includes a capacitor C2. The resistance measuring means 15a detects an insulation resistance between the connection terminal 31 and the correction circuit 15b to check for electrical loss from the stator 1 through the test liquid 17th .

The test system further comprises the control unit 13th . The control unit 13th is with the vacuum pump 5 and the testing device 15th electrically connected. The motor housing 3a is arranged on a scale 33. The control unit 13th is also electrically connected to the balance 33 and the pressure sensor 25. The first and second opening / closing valves 9 and 16 , the air outlet valve 21 and the electromagnetic open / close unit 14 are associated with the control unit 13th also electrically connected. The control unit 13th controls these components.

The acceptability of the stator 1 is checked by the test system. As in the 1 and 2 shown is the stator 1 in the engine compartment 3c serving as the test chamber in the arranging step S1 arranged. As in 3 shown is the stator 1 already in the engine chamber 3c fixed to the motor housing 3a. As in 4th As shown, there are three electrical connector pins 29 attached to the group block 1c are provided outside the motor housing 3a through the respective through holes 3f and the respective sealing members 1g formed in the motor housing 3a. The connection terminal 31 is connected to one of the three electrical connection pins 29.

Then, as in 6th is shown, the lid body 3b is closed. The control unit closes 13th the first opening / closing valve 9 and the second opening / closing valve 16 in a state in which the test liquid 17th in the engine compartment 3c does not exist. The control unit 13th also operates the electromagnetic open / close unit 14 to close the suction port 3e. The engine chamber 3c is in the arranging step S1 sealed.

Then, as in the 1 and 7th is shown activates the control unit 13th the vacuum pump 5 and opens the first opening / closing valve 9 in the pressure reduction step S2 . The test liquid 17th becomes from the liquid tank 7th into the motor chamber 3c not fed, and the pressure in the motor chamber 3c is by the vacuum pump 5 reduced. The components of the test liquid therefore volatilize 17th not through the vacuum pump 5 . Also, the predetermined degree of vacuum is achieved in a shorter and more stable period of time than in a case according to the conventional test method because of a pressure of the test liquid 17th is not reduced.

The control unit 13th determines whether the predetermined level of vacuum in the motor chamber 3c is reached or not based on a signal from the pressure sensor 25, and performs the diving step S3 by when the predetermined level of vacuum in the motor chamber 3c is achieved, as in the 1 and 7th is shown. In this case the control unit closes 13th first the first opening / closing valve 9 and deactivates the vacuum pump 5 . Thus, the predetermined degree of vacuum in the motor chamber becomes 3c maintain.

Then the control unit opens 13th the second opening / closing valve 16 . This causes the test liquid 17th from the liquid tank 7th into the motor chamber 3c is fed. The test liquid 17th is electrically conductive. The stator 1 begins in the test liquid 17th to immerse. Because the hydration passages 8a and 8b are provided on the lid body 3b provided on the motor housing 3a, the test liquid becomes 17th in the liquid tank 7th simply into the motor chamber 3c fed. The test liquid 17th in the liquid tank 7th is preheated by the heating means 7a. This enables a temperature of the motor housing 3a on which the stator 1 in the engine compartment 3c is fixed by the shrink fit, equal to a temperature of the test liquid 17th to be in an early stage, which prevents the insulation resistance from changing at the early stage.

The control unit then determines 13th whether the stator 1 into the test liquid 17th is submerged or not based on a signal from the balance 33 and when a sufficient volume of the test liquid 17th for immersing the stator 1 is supplied, the control unit closes 13th the second opening / closing valve 16 . This stops supplying the test liquid 17th into the motor chamber 3c . The test liquid 17th is maintained in a vacuum in this way.

As in 1 is shown, the control unit opens 13th after the dive step S3 the air outlet valve 21 and performs the venting step S4 by, with the air in the motor chamber 3c to the environment is omitted. By the test liquid 17th When exposed to the environment, air bubbles will be only marginally in the test liquid 17th are present under the reduced pressure from the test liquid 17th removed.

After the exhaust step S4 measures the control unit 13th the electrical conductivity of the test liquid 17th in the engine compartment 3c . If the electrical conductivity falls within a certain range, activates the control unit 13th the testing device 15th to complete the test step S5 perform. More specifically, the insulation resistance is detected by the resistance measuring means 15a, and the electrical loss from the stator 1 through the test liquid 17th is checked.

According to the test method and the test system for the stator, the pressure in the motor chamber 3c reduced in a state in which the test liquid 17th in the engine compartment 3c in which the stator 1 is arranged is absent because of the pressure reducing step S2 after the arranging step S1 is carried out. Therefore, the prints in the group block 1c and quickly reduced the uniformly pressurized passages. Subsequently by taking the plunge step S3 is carried out, the test liquid penetrates 17th quickly to the group block 1c and the uniformly pressurized passages to the core simply by supplying the test liquid 17th a.

In addition, according to the test method and the test system for the stator, the air bubbles that are only slightly in the test liquid 17th are present under the reduced pressure from the test liquid 17th removed because of the air exhaust step S4 between the dive step S3 and the test step S5 is carried out. This ensures the high test accuracy.

As a result, according to the test method and system for the stator, the acceptability of the stator becomes 1 highly accurately checked in a short and stable period of time even in a case where the stator 1 the group block 1c and the uniformly pressurized passage in the stator 1 is trained.

At the stator 1 offer the group block 1c and finally, the electric compressor for a vehicle has excellent durability because the uniformly pressurized passages create a pressure difference between the inside and the outside of the group block 1c to reduce.

In addition, in this embodiment, the motor housing 3a, on which the stator 1 is fixed as part of the test container 3 used. This enables quick assembly of the motor housing 3a including the stator 1 in the electric compressor for a vehicle after the test.

A test system of a comparative example is prepared by the correction circuit 15b from the test device 15th of the present embodiment is removed and other configuration is the same as that of the embodiment of the present invention. Then the stator 1 tested by the same test method as the embodiment of the present invention.

It is known that a combined leakage current, ie a total of a charging current, an absorption current and a leakage current, in the test liquid 17th flows when a DC voltage is applied to the stator 1 is created in the test liquid 17th is immersed, which is a dielectric. The combined leakage flow shows a decrease along with a change in the absorption flow, then the decrease slows down but continues until the absorption flow is no longer acting and eventually the combined leakage flow converges to the leakage flow.

8th is obtained by displaying changes in the combined leakage currents with the insulation resistances obtained by the test method and system of the embodiment of the present invention and the test method and system of the comparative example.

According to the test method and the test system of the comparative example, the charging current flows in a period between 0 and Tc1, the absorption current flows in a period between Tc1 and Tc2, and the leakage current flows in from Tc2. On the other hand, according to the test method and the test system of the embodiment of the present invention, the charge current flows in a period between 0 and Te1, the absorption current flows in a period between Te1 and Te2, and the leakage current flows in from Te2. In comparison between the embodiment of the present invention and the comparative example, ΔTela, that is, the time between Te1 and Te2 of the embodiment of the present invention is greater than ΔTcla, that is, the time between Tc1 and Tc2 of the comparative example. That is, the correction circuit 15b smooths the change characteristics of the absorption current between a time and the insulation resistance. The absorption current flows between the resistance measuring means 15 a and the connection terminal 27.

As a result, according to the test method and system of the comparative example, the insulation resistance detected in a short period of time such as ΔTcla is likely to vary, so that reliability deteriorates. On the other hand, according to the test method and system of the embodiment of the present invention, the insulation resistance detected in a long period of time such as ΔTela hardly changes, which ensures high reliability.

The test of the acceptability of the stator is also used 1 through the insulation resistance also a safety evaluation of the compressor, if the stator 1 is used for the compressor after the test, and a refrigerant and a lubricant, which are also dielectrics, fill the motor housing 3a. Therefore, according to the test method and system of the present invention, the stator represents 1 that is considered acceptable when testing the acceptability of the stator 1 is determined to ensure a high level of safety when used for the compactor.

The embodiment according to the present invention has been described above, but the scope of the present invention is not limited to the embodiment described above and is intended to include all changes equivalent in meaning and scope of the invention.

For example, in the embodiment, the acceptability of the stator used in the motor section of the electric compressor for a vehicle is checked. However, the test method and system for the stator of the present invention are applicable to stators used for other motors, alternators, or the like for testing the acceptability of the stators.

In this embodiment, the uniformly pressurized passages are formed between the tubes or the sets of conduits. However, the uniformly pressurized passages can be formed directly in the group block. Alternatively, an insertion hole formed in the group block to immediately cause the conduit to pass directly therethrough can be used as the uniformly pressurized passage without providing the pipe.

A liquid supply pump can be located between the liquid tank 7th and the test container 3 to be provided. The testing device 15th can reduce the acceptability of the stator 1 check by detecting an amount of leakage current between the connection terminal 27 and the electrical connection pin 29. Other temperature control means for controlling the temperature of the test liquid can be used instead of the heating means 7a.

Commercial applicability

The present invention can be applied to a manufacturing facility for an engine and the like.

List of reference symbols

1

stator

1a

Kitchen sink

1b

core

1c

Group block

1d

pipe

1e

connection

1f

Sealing element

1i

management

3

Test container

3c

Test chamber (motor chamber)

5

Pressure reduction unit (vacuum pump)

7th

Liquid tank

8a, 8b

Liquid supply passage

9

first opening / closing valve

13th

Control unit

15th

Testing device

15b

Correction circuit

16

second opening / closing valve

17th

Test liquid

19a, 19b

Pressure reduction passage

21

Air outlet valve

S1

Arrangement step

S2

Pressure reduction step

S3

Plunge step

S4

Air outlet step

S5

Test step

Claims (9)

Test method for a stator for testing an electrical loss from the stator through a test liquid, which is electrically conductive, by immersing the stator in the test liquid in a test chamber, the stator comprising a coil having an insulation-coated conductive wire, the stator the coil, a lead made of the insulation coated conductive wire extending from the coil, a terminal electrically connected to the lead, a group block that receives the terminal, and a unitary pressurized passage including a Provides connection between an inside and an outside of the group block, the test method being characterized in that it comprises: an arranging step in which the stator is arranged in the test chamber in a sealed state; a pressure reducing step in which a pressure in the test chamber is reduced after the arranging step; a dipping step in which the stator is dipped in the test liquid after the pressure reducing step; and a checking step of checking electrical leakage from the stator by the checking liquid after the dipping step. Test procedure for the stator Claim 1 , characterized in that the stator comprises a tube extending through the group block and receiving the conduit, a gap is sealed between the tube and the group block, and the uniformly pressurized passage is formed between the tube and the conduit. Test procedure for the stator Claim 2 wherein the pipe is formed so that a space between the pipe and the conduit is narrowed. Test method for the stator according to one of the Claims 1 until 3 wherein the checking step is performed by a correction circuit that smooths change characteristics between time and resistances of an absorption current detected from the stator. Test method according to one of the Claims 1 until 4th wherein an air discharging step in which air in the test chamber is discharged to an environment is performed between the dipping step and the testing step. A test system for a stator that includes a coil with an insulation coated conductive wire, a lead made of the insulation coated conductive wire extending from the coil, a terminal that is electrically connected to the lead, a group block that is the terminal and comprises a uniformly pressurized passage which provides a connection between an inside and an outside of the group block, characterized in that the test system comprises: a test container which has a test chamber in which the stator can be arranged in a sealed state and can be immersed in a test liquid that is electrically conductive; a pressure reduction unit connected to the test chamber through a pressure reduction passage and configured to reduce a pressure in the test chamber; a liquid tank that is connected to the test chamber through a liquid supply passage and stores the test liquid; a first opening / closing valve configured to open and close the pressure reduction passage; a second opening / closing valve configured to open and close the liquid supply passage; a control unit configured to control at least the first opening / closing valve and the second opening / closing valve; and a test device configured to test an electrical loss from the stator by the test liquid, wherein the control unit closes the second opening / closing valve and opens the first opening / closing valve in a state in which the test liquid in the test chamber, in which the stator is arranged does not exist, the control unit closes the first opening / closing valve and opening the second opening / closing valve when a predetermined degree of vacuum is reached in the test chamber, and the control unit the second opening / closing valve closes and activates the test device when the stator is immersed in the test liquid in the test chamber. Test system for the stator Claim 6 wherein the stator forms part of a motor that can be mounted on an electric compressor, part of the test container forms a motor housing of the electric compressor for receiving the motor, and the motor housing an electrical connecting pin extending through the motor housing and a sealing element that seals a gap between the electrical connection pin and the motor housing, the electrical connection pin having one end electrically connected to the terminal and the other end electrically connected to the test device. Test system for the stator Claim 6 or 7th wherein the test apparatus comprises a correction circuit that smooths change characteristics between time and resistances of an absorption current detected from the stator. Test system for the stator according to one of the Claims 6 until 8th wherein the test system further comprises an air discharge valve configured to discharge air in the test chamber to an environment, and after the control unit closes the second opening / closing valve when the stator is immersed in the test liquid in the test chamber, the control unit operates , that this Air outlet valve releases the air in the test chamber to the environment and activates the test device.

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