Patent ID: 12203480

Throughout the drawings and the detailed description, the same reference numerals refer to the same elements. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience.

DETAILED DESCRIPTION

This description provides a comprehensive understanding of the methods, apparatuses, and/or systems described. Modifications and equivalents of the methods, apparatuses, and/or systems described are apparent to one of ordinary skill in the art. Sequences of operations are exemplary, and may be changed as apparent to one of ordinary skill in the art, with the exception of operations necessarily occurring in a certain order. Descriptions of functions and constructions that are well known to one of ordinary skill in the art may be omitted.

Exemplary embodiments may have different forms, and are not limited to the examples described. However, the examples described are thorough and complete, and convey the full scope of the disclosure to one of ordinary skill in the art.

In this specification, “at least one of A and B” should be understood to mean “only A, only B, or both A and B.”

A motor-driven compressor10according to one embodiment will now be described with reference toFIGS.1and2. The motor-driven compressor10is used in a vehicle air conditioner24.

Overall Configuration of Motor-Driven Compressor10

As shown inFIG.1, the motor-driven compressor10includes a tubular housing11. The housing11is made of metal. The housing11includes a discharge housing member12and a motor housing member13. The discharge housing member12and the motor housing member13are made of, for example, aluminum. The discharge housing member12is coupled to the motor housing member13. The motor housing member13includes a plate-shaped housing end wall14and a tubular housing circumferential wall15, which extends from the outer circumferential edge of the housing end wall14. The housing circumferential wall15includes a suction port16. Refrigerant, which is fluid, is drawn into the motor housing member13through the suction port16from the outside. The housing11thus includes the suction port16.

The motor-driven compressor10includes a compression unit17, which compresses the refrigerant, an electric motor18, which drives the compression unit17, and an inverter19, which drives the electric motor18. The motor-driven compressor10also includes a rotary shaft20. The rotary shaft20is accommodated in the motor housing member13with the axis of the rotary shaft20agreeing with the axis of the housing circumferential wall15. The housing circumferential wall15thus extends in the axial direction of the rotary shaft20.

The compression unit17and the electric motor18are accommodated in the motor housing member13. Specifically, the housing circumferential wall15includes a motor accommodating chamber15a, which accommodates the electric motor18. The housing11thus accommodates the electric motor18. The compression unit17and the electric motor18arranged in the axial direction of the rotary shaft20. The electric motor18is arranged between the compression unit17and the housing end wall14. The electric motor18rotates the rotary shaft20. The compression unit17is driven by rotation of the rotary shaft20to compress the refrigerant.

The compression unit17is of, for example, a scroll type that includes a fixed scroll (not shown) fixed in the motor housing member13and a movable scroll (not shown) opposed to the fixed scroll.

The electric motor18includes a tubular stator21and a rotor22, which is arranged on the inner side of the stator21. The rotor22rotates integrally with the rotary shaft20. The stator21surrounds the rotor22. The rotor22includes a rotor core22a, which is fixed to the rotary shaft20, and permanent magnets (not shown), which are provided on the rotor core22a. The stator21includes a tubular stator core21aand a motor coil21b, which is wound about the stator core21a.

The suction port16is connected to a first end of an external refrigerant circuit23. The discharge housing member12includes a discharge port12a. The discharge port12ais connected to a second end of the external refrigerant circuit23. The suction port16connects the outside and the motor accommodating chamber15ato each other. Refrigerant is drawn into the motor accommodating chamber15aof the motor housing member13from the external refrigerant circuit23through the suction port16. The drawn refrigerant is compressed by the compression unit17when the compression unit17is driven, and flows out to the external refrigerant circuit23through the discharge port12a. The refrigerant that has flowed out to the external refrigerant circuit23returns to the motor housing member13through the suction port16via a heat exchanger and an expansion valve (neither is shown) of the external refrigerant circuit23. The motor-driven compressor10and the external refrigerant circuit23are part of the vehicle air conditioner24.

Configuration of Inverter Case25

The motor-driven compressor10includes a tubular inverter case25. The inverter case25accommodates the inverter19. The inverter case25includes a plate-shaped case end wall26and a tubular case circumferential wall27, which extends from the outer circumference of the case end wall26. The case end wall26is opposed to the housing end wall14in the axial direction of the rotary shaft20. The inverter case25is fixed to the motor housing member13by attaching the case end wall26to the housing end wall14. The inverter case25is thus fixed to the housing11. The compression unit17, the electric motor18, and the inverter19are arranged in the order in the axial direction of the rotary shaft20.

As shown inFIG.2, the inverter case25includes a seal circumferential wall28having a circular cross section. The seal circumferential wall28extends away from the case circumferential wall27from the outer circumferential edge of the case end wall26. The seal circumferential wall28extends in the axial direction of the rotary shaft20from the case end wall26. An inner circumferential surface of the seal circumferential wall28extends along an outer circumferential surface of the housing circumferential wall15. The seal circumferential wall28surrounds a section of the outer circumferential surface of the housing circumferential wall15. The seal circumferential wall28includes a proximal end connected to the case end wall26and a case end face29located at a distal end that is on a side opposite to the proximal end. The case end face29is an end face of the seal circumferential wall28in the axial direction.

Electrical Connection of Electric Motor18and Inverter19

As shown inFIG.1, the motor-driven compressor10has a through-hole30. The through-hole30extends through the housing end wall14and the case end wall26. The motor-driven compressor10also includes three conductive members31. For the illustrative purposes, only one of the conductive members31is illustrated inFIG.1. The conductive members31are supported by the case end wall26with a supporting plate32.

Each conductive member31is electrically connected to the inverter19. Each conductive member31extends from inside the inverter case25and through the through-hole30so as to protrude into the motor housing member13. The three conductive members31are respectively electrically connected to three motor wires34routed out of the electric motor18via a cluster block33arranged in the motor housing member13. Accordingly, the electric motor18and the inverter19are electrically connected to each other through the motor wires34, the cluster block33, and the conductive members31. The inverter19supplies power to the electric motor18through the conductive members31, the cluster block33, and the motor wires34, thereby driving the electric motor18.

Configuration of Housing Circumferential Wall15

As shown inFIG.2, the outer circumferential surface of the housing circumferential wall15includes a first housing outer circumferential surface40, a housing opposed surface41, and a second housing outer circumferential surface42. The first housing outer circumferential surface40is a section of the outer circumferential surface of the housing circumferential wall15that is surrounded by the seal circumferential wall28. The first housing outer circumferential surface40extends in the axial direction of the housing circumferential wall15. A first edge of the first housing outer circumferential surface40(the edge contacting the inverter case25) is opposed to the case end wall26in the axial direction of the housing circumferential wall15.

The housing opposed surface41is an annular opposed surface of the outer circumferential surface of the housing circumferential wall15that is opposed to the case end face29in the axial direction of the rotary shaft20. The housing opposed surface41extends outward in the radial direction of the rotary shaft20from a second edge of the first housing outer circumferential surface40(the edge on the side opposite to the first edge). The housing opposed surface41is a flat surface.

The second housing outer circumferential surface42is tubular and extends in the axial direction of the housing circumferential wall15. The second housing outer circumferential surface42extends from the outer circumferential edge of the housing opposed surface41and away from the inverter case25. The housing opposed surface41connects the first housing outer circumferential surface40and the second housing outer circumferential surface42to each other. The housing opposed surface41is a step surface that extends in the radial direction of the rotary shaft20between the first housing outer circumferential surface40and the second housing outer circumferential surface42. The outer diameter of the second housing outer circumferential surface42is larger than the outer diameter of the first housing outer circumferential surface40. The outer diameter of the second housing outer circumferential surface42is smaller than the outer diameter of the seal circumferential wall28.

Configuration of Seal Member50

The motor-driven compressor10includes an annular seal member50. The seal member50is provided between the inner circumferential surface of the seal circumferential wall28and the outer circumferential surface of the housing circumferential wall15. The seal member50includes a first seal portion51and a second seal portion52. The first seal portion51is tubular and extends in the axial direction. The second seal portion52is an annular flange that extends outward with respect to the first seal portion51.

The first seal portion51is arranged between and held by the inner circumferential surface of the seal circumferential wall28and the first housing outer circumferential surface40. The outer circumference of the first seal portion51is in close contact with the inner circumferential surface of the seal circumferential wall28. The inner circumference of the first seal portion51is in close contact with the first housing outer circumferential surface40. The first seal portion51thus provides a seal between the inner circumferential surface of the seal circumferential wall28and the first housing outer circumferential surface40of the housing circumferential wall15. Accordingly, in the motor-driven compressor10, the seal member50provides a seal between the inner circumferential surface of the seal circumferential wall28and the outer circumferential surface of the housing circumferential wall15.

Most of the second seal portion52is arranged between and held by the case end face29and the housing opposed surface41. A section of the second seal portion52that is opposed to the case end face29is in close contact with the case end face29. A section of the second seal portion52that is opposed to the housing opposed surface41is in close contact with the housing opposed surface41. The second seal portion52thus provides a seal between the case end face29and the housing opposed surface41. The seal member50extends in the radial direction of the rotary shaft20between the case end face29and the housing opposed surface41.

The outer circumferential edge of the second seal portion52, that is, the edge on the side opposite to the first seal portion51, protrudes from between the case end face29and the housing opposed surface41. The protruding outer circumferential edge of the second seal portion52extends along the case end face29and partially bulges over the second housing outer circumferential surface42. Thus, part of the seal member50extends to the outside of the housing11from between the case end face29and the housing opposed surface41. Also, the part of the seal member50is exposed to the outside of the housing11from between the case end face29and the housing opposed surface41.

Configuration of Conductor55

The seal member50includes an integrated annular conductor55that surrounds a section of the outer circumferential surface of the housing circumferential wall15. The conductor55is made of metal. The seal member50and the conductor55are integrated by insert molding. The conductor55is arranged between the case end face29and the housing opposed surface41. The conductor55is in contact with the case end face29. The conductor55is electrically connected to the seal circumferential wall28. The conductor55is in contact with the housing opposed surface41. The conductor55is thus electrically connected to the housing circumferential wall15of the motor housing member13. The conductor55is held between the case end face29and the housing opposed surface41. The inner diameter of the conductor55is larger than the inner diameter of the seal circumferential wall28. The outer diameter of the conductor55is equal to the outer diameter of the second housing outer circumferential surface42.

Operation

Operation of the present embodiment will now be described.

For example, the seal member50blocks water, for example, salt water, that attempts to enter the gap between the inner circumferential surface of the seal circumferential wall28and the outer circumferential surface of the housing circumferential wall15from outside. Accordingly, water is prevented from entering the through-hole30via the gap between the inner circumferential surface of the seal circumferential wall28and the outer circumferential surface of the housing circumferential wall15. As a result, water from the outside will not contact the conductive members31. Also, the seal member50extends in the radial direction of the rotary shaft20between the case end face29and the housing opposed surface41. Thus, the water blocked by, for example, the seal member50is prevented from accumulating in the gap between the case end face29and the housing opposed surface41.

Further, the conductor55is arranged between the case end face29and the housing opposed surface41. Thus, the conductor55blocks electromagnetic noise that attempts to pass through the gap between the case end face29and the housing opposed surface41. Accordingly, external electromagnetic noise is prevented from passing through the gap between the case end face29and the housing opposed surface41to enter the motor-driven compressor10. Also, electromagnetic noise inside the motor-driven compressor10is prevented from leaking to the outside through the gap between the case end face29and the housing opposed surface41.

Advantages

The above-described embodiment has the following advantages.

(1) The seal member50extends in the radial direction of the rotary shaft20between the case end face29and the housing opposed surface41. Thus, for example, water such as salt water that is blocked by the seal member50is prevented from accumulating in the gap between the case end face29and the housing opposed surface41. This improves the corrosion resistance of the motor-driven compressor10.

(2) When the motor housing member13is cooled by the refrigerant that is drawn into the motor housing member13through the suction port16from the outside, the seal member50is also cooled. This may cause the seal member50to contract. Even in this case, since part of the seal member50extends to the outside of the housing11from between the case end face29and the housing opposed surface41, no gap is created between the case end face29and the housing opposed surface41. Thus, for example, water that is blocked by the seal member50is prevented from accumulating in the gap between the case end face29and the housing opposed surface41.

(3) The conductor55is arranged between the case end face29and the housing opposed surface41. Thus, the conductor55blocks electromagnetic noise that attempts to pass through the gap between the case end face29and the housing opposed surface41. Accordingly, external electromagnetic noise is prevented from passing through the gap between the case end face29and the housing opposed surface41to enter the motor-driven compressor10. Also, electromagnetic noise inside the motor-driven compressor10is prevented from leaking to the outside through the gap between the case end face29and the housing opposed surface41.

(4) The conductor55is held between the case end face29and the housing opposed surface41. Accordingly, the part of the seal member50that is located between the case end face29and the housing opposed surface41is accurately positioned between the case end face29and the housing opposed surface41. This improves the sealing performance of the seal member50between the case end face29and the housing opposed surface41.

Modifications

The above-described embodiment may be modified as follows. The above-described embodiment and the following modifications can be combined as long as the combined modifications remain technically consistent with each other.

Part of the seal member50does not necessarily need to extend to the outside of the housing11from between the case end face29and the housing opposed surface41.

The conductor55does not necessarily need to be held between the case end face29and the housing opposed surface41. In this case, the conductor55may be arranged between the case end face29and the housing opposed surface41while being separated from the case end face29and the housing opposed surface41.

The conductor55does not necessarily need to be arranged between the case end face29and the housing opposed surface41. The annular conductor55does not necessarily need to be integrated with the seal member50.

The outer diameter of the conductor55may be smaller than the outer diameter of the second housing outer circumferential surface42, or the outer diameter of the conductor55may be larger than the outer diameter of the second housing outer circumferential surface42.

The case end face29and the housing opposed surface41may extend in stepped shapes that conform to each other, and the seal member50may extend in a stepped shape between the case end face29and the housing opposed surface41.

The compression unit17is not limited to a scroll type, but may be, for example, a piston type or a vane type.

The motor-driven compressor10may be used in apparatuses other than the vehicle air conditioner24. For example, the motor-driven compressor10may be mounted on a fuel cell vehicle and use the compression unit17to compress air, which is a fluid supplied to the fuel cell.

Various changes in form and details may be made to the examples above without departing from the spirit and scope of the claims and their equivalents. The examples are for the sake of description only, and not for purposes of limitation. Descriptions of features in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if sequences are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined differently, and/or replaced or supplemented by other components or their equivalents. The scope of the disclosure is not defined by the detailed description, but by the claims and their equivalents. All variations within the scope of the claims and their equivalents are included in the disclosure.