WO2021066372A1

WO2021066372A1 - Device for driving a compressor and process for mounting the device

Info

Publication number: WO2021066372A1
Application number: PCT/KR2020/012779
Authority: WO
Inventors: Bernadette Goebbels; Hendrik Varain; Fabian Zaschke-Kriesche
Original assignee: Hanon Systems
Priority date: 2019-10-01
Filing date: 2020-09-22
Publication date: 2021-04-08
Also published as: DE102019126531A1; DE102019126531B4

Abstract

The present invention relates to a device (3) for driving a compressor of a vapourous fluid with a housing (2) that features a cooling surface and a power supply arrangement (5). The arrangement (5) exhibits at least one switching element (11, 11a), a support element (13) with a lateral surface (13a), as well as a cover element (14) and is arranged with the lateral surface (13a) in contact with the housing (2) in the area of the cooling surface of the housing (2). The switching element (11, 11a) is arranged inside a volume enclosed by the support element (13) and the cover element (14). The lateral surface (13a) of the support element (13) is produced with a pass-through opening (13b). Here, the at least one switching element (11, 11a) is arranged such that it projects through the pass-through opening (13b) and is in contact with the housing (2) in the area of the cooling surface of the housing (2). The present invention also relates to a process for mounting the device (3).

Description

DEVICE FOR DRIVING A COMPRESSOR AND PROCESS FOR MOUNTING THE DEVICE

The present invention relates to a device, in particular an electric motor, for driving a compressor to compress a vapourous fluid, specifically a refrigerant. The device is produced with a housing that comprises a cooling surface and a power supply arrangement. The arrangement exhibits at least one switching element, a support element with a lateral surface, as well as a cover element, wherein the lateral surface is in contact with the housing in the area of the housing's cooling surface. The switching element is arranged inside a volume enclosed by the support element and the cover element. The compressor can be used in the refrigerant circuit of a motor vehicle air-conditioning system.

The present invention also relates to a process for mounting the device used to drive the compressor of a vapourous fluid.

Compressors known from the state of the art for mobile applications, in particular as air-conditioning systems in motor vehicles, that are used for conveying refrigerant through a refrigerant circuit, also known as refrigerant compressors, are often constructed as piston compressors with variable displacement or as scroll compressors irrespective of the refrigerant used. The compressors are driven either via a belt pulley or electrically here.

Alongside the electric motor for driving the respective compression mechanism, an electrically driven compressor also exhibits an inverter for driving the electric motor. The inverter is used to convert the direct current (DC) supplied by a vehicle battery into alternating current (AC), which is then fed to the electric motor through electrical connections.

The inverter exhibits a PCB that contains switching elements, such as power transistors, which together form a compressor switching device. The power transistors of an inverter, also known as power switches, generate heat as a result of switching losses and conduction losses that needs to be dissipated by the transistors. The dissipated heat, in particular of an electrically driven refrigerant compressor, should ideally be transferred to the refrigerant. Here, the power transistors are advantageously to be arranged on an outer side of the compressor housing such that they are in contact with the housing and can therefore conduct heat. The power transistors should be connected to the housing in the section of the housing with the lowest temperature, which is regularly located in the area of the intake port where the refrigerant flows into the compressor.

In the following, the section of the housing with the lowest temperature is also referred to as the cooling surface/area of the housing, specifically of the motor housing. The power transistors can be attached directly to the cooling surface in such a way that they conduct heat here.

In the design of conventional modular inverters, the power transistors are arranged on an additional support element, which itself is then attached to the cooling surface of the housing together with the power transistors. In this case, an additional wall of the support element is provided between the power transistors and the cooling surface of the housing. The surface of the wall on the support element is in contact with the cooling surface of the housing, which leads to a deterioration in heat dissipation from the transistor in comparison with an arrangement where the transistor is in direct contact with the cooling surface of the housing.

Each power transistor is to be thermally contacted either to the cooling surface of the housing or to the wall of the support element.

A good thermal contact can, for example, be produced using matched surface roughnesses. However, air pockets between the respective power transistor and the cooling surface of the housing or the wall of the support element must in particular be avoided here, as these can reduce heat transfer between the components.

In conventional units, thermal interface materials such as thermal paste or foils are used to guarantee good thermal contact and avoid the aforementioned air pockets. In addition to this, a certain mounting pressure can be applied to the power transistors, which then also presses on the cooling surface of the housing or the wall of the support element. Alongside establishing a good thermal contact, this pressure on the transistors also serves to attach the transistors or the inverter to the housing in a way that makes the connection vibration-resistant.

The notion of applying compressive force, which acts in the direction of the cooling surface of the housing or the wall of the support element, through a direct screw connection or a clamped connection, for example using spring elements, is known from the state of the art. Here, the power transistors can be screwed down to the cooling surface of the housing or the wall of the support element.

When mounting the power transistors directly to the cooling surface of the housing, with potential inclusion of thermal interface materials between the power transistors and the cooling surface, the transistors are either screwed down or clamped to the housing. In an alternative, modular design of the inverter, the power transistors are attached to the wall of the support element. After the respective attachment of the power transistors, a PCB is then attached. The connections of the transistors are arranged such that they are plated through the PCB and then soldered to the PCB.

Since the PCB is fitted as the final component during manufacture of the electrically driven compressor with power transistors arranged directly on the cooling surface of the housing, the selective soldering of the power transistors to the PCB is also performed directly on the compressor housing. Here, the processes of mounting and soldering the PCB to the already fitted housing are both very complex and time consuming from a production perspective. The alternative, modular design of the inverter with the power transistors attached to the wall of the support element is therefore generally preferable from a production perspective.

For heat dissipation from the power transistor to the cooling surface of the housing, however, the modular design of the inverter requires an additional heat passage through the wall of the support element, as well as an additional heat transfer section between the support element and the cooling surface of the housing, which reduces the heat transfer from the transistor to the cooling surface.

The object of the invention lies in provision and improvement of a modular inverter for a device used to drive an electrically driven compressor of a vapourous fluid, in particular an electric motor, that can also be fitted easily and therefore quickly. The focus here is on dissipating as much heat as possible from the power transistors through optimum heat transfer, in particular transferring the heat to the fluid that is to be compressed in the compressor. The device should employ a basic design and therefore be easy to produce in order to minimise manufacturing costs.

The task is resolved by the subject matter with the characteristics of the independent patent claims. Further embodiments are provided in the dependent patent claims.

The object is resolved by a device according to the invention for driving a compressor of a vapourous fluid, in particular an electric motor. The device is produced with a housing featuring a cooling surface and a power supply arrangement. The arrangement exhibits at least one switching element, a support element with a lateral surface, as well as a cover element, wherein the lateral surface is in contact with the housing in the area of the housing's cooling surface. The switching element is arranged inside a volume enclosed by the support element and the cover element.

According to the design of the invention, the lateral surface of the support element, itself advantageously produced from a metal, exhibits a pass-through opening. Here, the at least one switching element is arranged such that it projects through the pass-through opening and is in contact with the housing in the area of the housing's cooling surface. The switching element is preferably produced as a power transistor.

As per a further embodiment of the invention, the arrangement exhibits at least one spring element, preferably produced from a elastically deformable material, in particular a metal, and arranged on the support element, that is itself preferably arranged inside the volume enclosed by the support element with the cover element. Here, the at least one spring element is attached to the support element in an area of the support element's lateral surface that faces away from the housing, in particular to a mounting surface produced on a edge surrounding the pass-through opening of the lateral surface of the support element. The spring element is advantageously connected to the support element via at least one screw connection.

As per a preferred embodiment of the invention, one side of the at least one spring element is in contact with the switching element that is produced on the opposite side to the side of the switching element that faces the cooling surface of the housing, meaning that the switching element is arranged such that it is pressed by the spring element in the direction of the cooling surface of the housing.

An advantage of the invention lies in the fact that the at least one spring element exhibits the shape of a small plate with at least one convex strip that projects from the base surface. Here, the strip is arranged such that it projects into the pass-through opening on the lateral surface of the support element. The curvature of the at least one strip is preferably aligned with a convex surface in the direction of the switching element and is in contact with the convex surface on the switching element.

In an embodiment of the arrangement with at least two switching elements, one strip of a spring element can be assigned to each switching element. Here, the switching elements can be arranged in pairs, wherein one strip of a spring element produced with two strips is assigned to each switching element.

According to another advantageous embodiment of the invention, the arrangement exhibits at least one PCB that is attached to the support element. Here, the PCB is arranged inside the volume enclosed by the support element with the cover element.

The at least one switching element is preferably connected to the PCB, in particular soldered to the PCB. Here, the spring element is preferably arranged between the PCB and the switching element.

As per a further embodiment of the invention, the support element exhibits a perimeter wall that is arranged around the entire edge of the lateral surface, is essentially aligned orthogonally relative to the lateral surface and is connected to the lateral surface on a first end face.

The cover element is advantageously produced such that it can be arranged on a second end face of the perimeter wall of the support element that faces the first end face and thereby seals the arrangement. Here, a first sealing element can be arranged between the second end face of the support element's perimeter wall and the cover element.

The task is also resolved by an inventive method for mounting the device used to drive a compressor of a vapourous fluid, in particular an electric motor. This method exhibits the following steps:

- Premounting a power supply arrangement as a modular component with

- Arrangement of at least one switching element in a pass-through opening produced in a lateral surface of a support element, wherein connections of the switching element project into a volume enclosed by the support element with a cover element and a surface of the switching element projects through the pass-through opening,

- Attachment of the switching element and

- Sealing of the arrangement by the cover element, as well as

- Arrangement and attachment of the arrangement to a housing of the device, so that the surface of the switching element which projects through the pass-through opening of the support element is in contact with a cooling surface of the housing.

As per a further embodiment of the invention, at least one spring element is attached to a contact surface produced on an edge of the pass-through opening provided in the support element when premounting the arrangement. Here, the spring element is arranged such that it projects into the pass-through opening and is connected to the support element, in particular screwed down.

When premounting the arrangement, a pre-assembled PCB is advantageously connected to the support element, for example screwed down.

An advantage of the invention lies in the fact that connections of the switching element are arranged such that they are plated through the PCB and then connected to the PCB, in particular soldered. Here, the modularity in particular allows the PCB to be soldered to the switching elements without the presence of the housing. In addition to this, a spring element is arranged between the PCB and the switching element that exerts pressure on the switching element in the direction of the housing.

To establish the connections of the switching element to the PCB, the switching element is preferably moved into a mounting position by a mounting device in a direction running towards the PCB and against a compressive force that is applied by the spring element. The mounting device is then removed after establishing the connections of the switching element to the PCB.

As per a preferred embodiment of the invention, the surface of the switching element facing the housing is pressed against the cooling surface of the housing due to the compressive force generated by the spring element when attaching the arrangement to the housing.

When the device is mounted, the spring element is in contact with the switching element in an elastically deformed way. As a result of the pressure applied by the elastic deformation of the spring element on the switching element, the switching element is pressed against the cooling surface of the housing in such a way that optimum heat transfer from the switching element to the cooling surface is guaranteed. Here, at least one thermal interface material, such as a thermal paste or foil, is preferably arranged between the switching element and the cooling surface of the housing.

The advantageous embodiment of the invention allows the device to be used to drive a compressor, in particular an electric motor, for compressing a vapourous fluid for a compressor of a refrigerant in a refrigerant circuit of a motor vehicle air-conditioning system.

Above all, use of the modular arrangement, specifically of an inverter for an electric motor of a refrigerant compressor, in connection with use of the spring force of metallic spring elements, allows the thermal influence, in particular of the switching elements / power transistors, to be significantly reduced over devices known from the state of the art.

As a result of the pass-through opening in the support element, facing the cooling surface of the housing, a thermal resistance in the form of an additional wall is avoided in comparison with the conventional structure of an inverter, which leads to improved cooling capacity of the power transistors, as the power transistors are in direct thermal contact with the cooling surface. The thermal contact, and thereby also the heat transfer process, are both improved with the arrangement of the at least one thermal interface material between the power transistor and the cooling surface of the housing.

The device according to the invention for driving a compressor of a vapourous fluid and the process for mounting the device collectively exhibit various other advantages:

- Optimum heat transfer, in particular to the fluid that is to be compressed in the compressor, with the maximum thermal energy that can be dissipated by the power transistors

- Simple design of the arrangement, facilitating easy production and therefore low manufacturing costs

- Easy and time-saving assembly of the arrangement and mounting of the arrangement to the housing, as well as

- Spring elements that deliver the requisite force for pressing the power transistors against the cooling surface of the housing throughout the entire service life at various temperatures and thereby regardless of the temperature.

Further details, features and benefits of embodiments of the invention result from the following description of embodiment examples with reference to the accompanying drawings. These display the following:

Fig. 1: A sectional view of an electrically driven compressor with a device, in particular an electric motor, for driving a compression mechanism and an arrangement of an inverter.

Fig. 2: An exploded perspective view of the inverter arrangement.

Fig. 3a: A perspective view of the support element of the inverter arrangement with a pass-through opening and mounting surfaces for spring elements.

Fig. 3b: The support element from Fig. 3a with spring elements arranged on the mounting surfaces.

Figs. 3c & 3d: The support element from Figs. 3a and 3b with PCB fitted, shown in both a frontal and rear view.

Fig. 3e: The pre-assembled support element with power transistors inserted into the PCB and soldered to the PCB.

Figs. 4a to 4c: The arrangement of the assembled modular inverter in a side view, as well as a perspective frontal view and rear view.

Fig. 5: A combination of the compressor housing with the arrangement of the modular inverter as an exploded perspective view.

Fig. 1 shows a sectional view of an electrically driven compressor 1 with an electric motor 3 arranged in a housing 2 as a device for driving a compression mechanism 4 and an arrangement 5 of an inverter. The electric motor 3 is powered via a switching device 6 of the arrangement 5.

The electric motor 3 exhibits a stator 7 with an essentially hollow cylinder-shaped stator core and coils wound on the stator core, as well as a rotor 8 arranged inside the stator 7. The rotor 8 is set into rotation when electrical energy is supplied to the coils of the stator 7 via a connection arrangement 9. The connection arrangement 9 is produced on an end face of the stator 7 and exhibits a large number of electrical connections.

The rotor 8 is arranged coaxially inside the stator 7 and in such a way that it can be rotated around a rotary axis. A drive shaft 10 can be produced integrally with the rotor 8 or as a separate element.

The electric motor 3 and the compression mechanism 4, produced in the form of a scroll compressor with one fixed and one orbiting scroll, are arranged inside a volume enclosed by the housing 2. Here, the housing 2 comprises a first housing element for mounting the electric motor 3 and a second housing element for mounting the compression mechanism 4, preferably produced from a metal, in particular an aluminium.

The orbiting scroll of the compression mechanism 4, in which the vapourous fluid, specifically a refrigerant, is compressed, is driven via the drive shaft 10 that is connected to the rotor 8 of the electric motor 3. As per an embodiment not shown, the compression mechanism can, for example, also be produced with a wobble plate.

The switching device 6 for controlling operation of the electric motor 3 exhibits a PCB 12 that is produced with various switching elements 11. Various control circuits and components are premounted on the PCB 12 with electrical connections and powered by an external power source via a power cable.

The PCB 12 with the switching elements 11 is arranged inside a support element 13 of the inverter arrangement 5 and fixed to the support element 13. The arrangement 5 is sealed off by a cover element 14.

Fig. 2 shows the inverter arrangement 5 in an exploded perspective view.

The support element 13, produced as a mounting element and a housing element, exhibits a lateral surface 13a with a pass-through opening 13b that, when the compressor is fitted, is arranged and aligned with a surface facing the housing 2 in the direction of a cooling surface of the housing 2 of the compressor 1 that is not shown or of the electric motor 3 of the compressor 1. Here, the support element 13, preferably produced from a metal, is arranged such that the lateral surface 13a containing the pass-through opening 13b and the area of the lateral surface 13a facing the housing 2 is in contact with the housing 2.

The support element 13 also exhibits a perimeter wall 13c that is arranged around the entire edge of the lateral surface 13a, is essentially aligned orthogonally relative to the lateral surface 13a and is connected to the lateral surface 13a on a first end face. On a second end face of the perimeter wall 13c, aligned distally to the first end face, the arrangement 5 can be sealed off with a cover element 14 that, when the arrangement 5 is fitted, is in contact with the support element 13 on the opposite end face of the support element 13 to the lateral surface 13a with the pass-through opening 13b, in particular the second end face of the perimeter wall 13c.

A first sealing element 15 is arranged between the second end face of the perimeter wall 13c of the support element 13 and the cover element 14 in order to seal off the arrangement 5. The shape of first sealing element 15 exhibits the contour of the second end face of the perimeter wall 13c of the support element 13, meaning that shape of the sealing element 15 and the end face of the perimeter wall 13c of the support element 13 match one another.

The cover element 14 is connected to the support element 13 with the first attachment elements 16, 16a using the first sealing element 15 that is arranged between the cover element 14 and the support element 13. Here, the first attachment elements 16, 16a are introduced into and arranged in first mounting holes 17 produced in the support element 13. The first attachment elements 16, 16a are preferably produced as screw connections with the first mounting holes 17.

The PCB 12, arranged in the volume enclosed by the support element 13 with the cover element 14, is also firmly connected to the support element 13 using second attachment elements 18. Here, the second attachment elements 18 are also introduced into and arranged in second mounting holes 19 produced in the support element 13. The second attachment elements 18 are also preferably produced as screw connections with the second mounting holes 19.

The PCB 12 is intended for mounting switching elements 11, 11a, in particular switching elements produced as power transistors 11a, that are permanently connected to the PCB 12 via connections and are arranged such that they project through the pass-through opening 13b of the support element 13 when the arrangement 5 is fitted. Spring elements 20 are arranged between the PCB 12 and the power transistors 11a.

The spring elements 20, arranged inside the volume enclosed by the support element 13 with the cover element 14, are also firmly connected to the support element 13 on the edge surrounding the pass-through opening 13b using third attachment elements 18. Here, the third attachment elements 21 are introduced into and arranged in third mounting holes 22 that are produced in the support element 13. The third attachment elements 21 are also preferably produced as screw connections with the third mounting holes 22.

The spring elements 20, preferably produced from a metal and exhibiting the shape of small plates, are arranged with strips that curve outwards and project into the pass-through opening 13b. Here, the curves of the small plates are aligned with a convex surface facing in the direction of the power transistors 11a. One strip of a spring element 20 is assigned to each power transistor 11a. The spring elements 20 are each in contact with the convex surface on the power transistors 11a in the area of the curved strips, meaning that the power transistors 11a are pressed through the pass-through opening 13b and away from the PCB 12 or the support element 13.

With its modular design, the arrangement 5 represents a coherent unit, comprising the listed components, that can then be connected directly to the compressor, in particular the housing of the compressor. Here, the support element 13, which is aligned with the cooling surface of the housing with its pass-through opening 13b and the power transistors 11a arranged inside it, is pre-assembled with the spring elements 20 attached to the support element 13, preferably with screws, and with the power transistors 11a that are soldered to the PCB 12.

Figs. 3a to 3e show the conditions of the inverter arrangement 5 during the process of assembly of the arrangement 5 in a perspective view.

Fig. 3a shows the support element 13 of the arrangement 5 with the pass-through opening 13b that is aligned towards the cooling surface (not shown) of the housing 2 of the compressor 1, as well as mounting surfaces 13d for the spring elements 20 (also not shown). The mounting surfaces 13d produced on the area of the lateral surface 13a of the support element 13 that faces away from the housing 2 are machined in such a way that the full surface of each of the plate-like spring elements 20, as per Fig. 3b, is in contact with the mounting surfaces 13d. During assembly, the spring elements 20, which exhibit through-holes in the area of the third mounting holes 22 produced on the support element 13, are positioned against the mounting surfaces 13d and firmly connected, in particular screwed down, to the support element 13 using third attachment elements 21 that are introduced into the third mounting holes 22. Here, the spring elements 20 are each arranged such that the outward curving strips project into the pass-through opening 13b.

The PCB 12, which is pre-assembled and houses various items, including switching elements, is then fixed to the support element 13 in the area of the second mounting holes 19, as also shown in Fig. 3c. Here, the PCB 12 is firmly connected to the support element 13, in particular screwed down, via second attachment elements 18 that are introduced into the second mounting holes 19. Fig. 3c shows the support element 13 with fitted PCB 12 in a frontal view, whereas the support element 13 with the fitted PCB 12 from Fig. 3d shows a rear view.

Fig. 3e shows the support element 13 with the PCB 12 already pre-assembled and power transistors 11a from the arrangement 5 both inserted into the PCB 12 and soldered to the PCB 12. The power transistors 11a are arranged such that they pass through the pass-through opening 13b of the support element 13, wherein the connections of the power transistors 11a are arranged such that they are inserted through or plated through the PCB 12 and soldered in place. The spring elements 20 are arranged between the PCB 12 and the power transistors 11a in such a way that they apply a pressure on the power transistors 11a.

The surfaces of the power transistors 11a which are aligned such that they face away from the PCB 12, also referred to as heat transfer surfaces - in particular surfaces for heat dissipation, project out of the pass-through opening 13b facing the cooling surface (not shown) of the housing 2 of the compressor 1 and out of the support element 13. Due to the compressive force applied to the power transistors 11a by the spring elements 20, the area of the lateral surface 13a of the support element 13 that faces the housing 2 and the surfaces of the power transistors 11a are not arranged flush to one another. The compressive force generated by the spring elements 20 is applied vertically relative to the plane of the lateral surfaces 13a of the support element 13 or to the plane of the pass-through opening 13b.

In order to connect, in particular to solder, the connections of the power transistors 11a to the PCB 12, the power transistors 11a are moved using a mounting device 23 in a movement direction 23a towards the PCB 12, and thereby against the acting direction of the compressive force applied by the spring elements 20, into a mounting location, as shown in Fig. 4a. Here, the mounting device 23 is pressed against the area on the lateral surface 13a of the support element 13 that is aligned with the housing 2 when the compressor is assembled in order to move the power transistors 11a into a predetermined mounting location for soldering to the PCB 12. In particular the strips of the spring elements 21 that are in contact with the power transistors 11a are elastically deformed here.

After connecting the power transistors 11a to the PCB 12 and removing the mounting device 23 from the support element 13, the power transistors 11a are pretensioned in the direction away from the PCB 12, wherein they project through the pass-through opening 13b and out of the support element 13.

Figs. 4b and 4c show the arrangement 5 of the assembled modular inverter in a side view, as well as in a perspective front and rear view. As the final step of assembly of the arrangement 5, the cover element 14 was fixed to the support element 13, in particular screwed down, via the first attachment elements 16 introduced into the first mounting holes 17 (not shown) with the intermediate first sealing element 15.

The power transistors 11a are each arranged in pairs. A arrangement of the power transistors 11a that deviates from the arrangement in pairs is also possible.

Fig. 5 shows a combination of the housing 2 of the compressor 1 with the arrangement 5 of the modular inverter in a exploded perspective view. The electric motor 3 and the compression mechanism 4 are arranged inside the housing 2. In the final step of mounting the arrangement 5 on the housing 2 of the compressor 1, first attachment elements 16, 16a are inserted through the cover element 14, through a second sealing element 24 that is arranged between the cover element 14 and the housing 2 and into mounting holes provided in the housing 2, where they are then preferably screwed down. The arrangement 5 is then fixed to the cover element 14 on the housing 2. Here, the power transistors 11a (not shown) are in contact with the areas on the cooling surface of the housing 2 that are aligned such that they face away from the PCB 12 (also not shown) and are pressed against the cooling surface of the housing 2, in particular for heat dissipation, as a result of the compressive force generated by the spring elements (also not shown). After completing the process for mounting the arrangement 5 on the housing 2 of the compressor 1, the power transistors 11a are in the correct position for the intended use. The connections of the power transistors 11a to the PCB 12, in particular the solder points, are free of any mechanical tension.

The spring elements 20 exhibit a defined stiffness. When mounting the arrangement 5 on the housing 2, a force that essentially acts in the axial direction of the device 1, in particular a spring force, is applied between each spring element 20 and thereby each power transistor 11a and the cooling surface of the housing 2. Due to the elastic properties of the spring element 20, this force presses each power transistor 11a in the direction of the housing 2. Here, the force acts on the power transistor 11a when the power transistor 11a is placed in contact with the housing 2 and the spring element 20 is elastically deformed. Once the procedure for mounting the arrangement 5 on the housing 2 is complete, a preload is generated through the elastic deformation of the spring elements 20 which clamps the power transistors 11a in place.

The spring force of the spring elements 20 is, in particular, designed such that it delivers sufficient force, even with a relatively small deflection, so that only a specific value of the compressive force is applied to the power transistors 11a when the arrangement 5 has not been mounted to the compressor 1, but that, when the arrangement 5 is fitted to the compressor 1, a sufficient compressive force is generated in order to press the power transistors 11a against the cooling surface of the housing 2 with a predetermined, sufficient compressive force. The spring constant of the spring elements 20 is consequently specified in such a way that firstly an excessive deflection of the power transistors 11a from a stop position is avoided when the compressor 1 is not fitted and secondly that application of a sufficient compressive force to the power transistors 11a and thereby the cooling surface of the housing 2 is guaranteed when the compressor 1 is fitted.

List of reference numbers

1 Compressor

2 Housing

3 Device, electric motor

4 Compression mechanism

5 Inverter arrangement

6 Switching device

7 Stator

8 Rotor

9 Connection arrangement

10 Drive shaft

11 Switching element

11a Switching element, power transistor

12 PCB

13 Support element

13a Support element lateral surface 13

13b Pass-through opening on lateral surface 13a of support element 13

13c Support element perimeter wall 13

13d Mounting surface

14 Cover element

15 (First) sealing element

16, 16a First attachment element for cover element 14, arrangement 5

17 First mounting hole on first attachment element 16

18 Second attachment element for PCB 12

19 Second mounting hole on second attachment element 18

20 Spring element

21 Third attachment element for spring element 20

22 Third mounting hole for third attachment element 21

23 Mounting device

23a Movement direction of mounting device 23

24 (Second) sealing element

Claims

Device (3) to drive a compressor of a vapourous fluid with a housing (2) with a cooling surface and a power supply arrangement (5), wherein the arrangement (5) exhibits at least one switching element (11, 11a), a support element (13) with a lateral surface (13a), as well as a cover element (14) and is arranged with the lateral surface (13a) in contact with the housing (2) in the area of the cooling surface of the housing (2), wherein the switching element (11, 11a) is arranged inside a volume enclosed by the support element (13) and cover element (14), characterised in that the lateral surface (13a) of the support element (13) is produced with a pass-through opening (13b) and the at least one switching element (11, 11a) is arranged such that it projects through the pass-through opening (13b) and is in contact with the housing (2) in the area of the cooling surface of the housing (2).
Device (3) according to claim 1, characterised in that the arrangement (5) is produced with at least one spring element (20) arranged on the support element (13).
Device (3) according to claim 2, characterised in that the at least one spring element (20) is arranged inside the volume enclosed by the support element (13) with the cover element (14).
Device (3) according to claim 2 or 3, characterised in that the at least one spring element (20) is arranged on the support element (13) in a area of the lateral surface (13a) of the support element (13) that itself is aligned such that it faces away from the housing (2).
Device (3) according to one of the claims 2 to 4, characterised in that the at least one spring element (20) is arranged on the support element (13) on a contact surface (13d) produced on a circumferential edge of the pass-through opening (13b) of the lateral surface (13a) of the support element (13).
Device (3) according to one of the claims 2 to 5, characterised in that the at least one spring element (20) is arranged with one side in contact with the switching element (11, 11a) produced opposite the side of the switching element (11, 11a) that is aligned with the cooling surface, so that the switching element (11, 11a) is arranged such that it is pressed in the direction of the cooling surface of the housing (2) by the spring element (20).
Device (3) according to one of the claims 2 to 6, characterised in that the at least one spring element (20) exhibits the form of a small plate with at least one convex strip projecting from a base area, wherein the strip is arranged such that it projects into the pass-through opening (13b) on the lateral surface (13a) of the support element (13).
Device (3) according to claim 7, characterised in that the curvature of the at least one strip is arranged such that it is aligned with a convex surface pointing in the direction of the switching element (11,11a) and the convex surface is in contact with the switching element (11, 11a).
Device (3) according to one of the claims 2 to 8, characterised in that the at least one spring element (20) is produced from an elastically deformable material, in particular a metal.
Device (3) according to one of the claims 2 to 9, characterised in that one strip of a spring element (20) is assigned to each switching element (11, 11a) when producing at least two switching elements (11, 11a).
Device (3) according to claim 10, characterised in that the switching elements (11, 11a) are arranged in pairs, wherein one strip of a spring element (20), itself produced with two strips, is assigned to each switching element (11, 11a).
Device (3) according to one of the claims 1 to 11, characterised in that the arrangement (5) is produced with at least one PCB (12) arranged on the support element (13).
Device (3) according to claim 12, characterised in that the at least one PCB (20) is arranged inside the volume enclosed by the support element (13) with the cover element (14).
Device (3) according to claim 12 or 13, characterised in that the at least one switching element (11, 11a) is arranged on the PCB (12).
Device (3) according to one of the claims 12 to 14, characterised in that a spring element (20) is arranged between the PCB (12) and the switching element (11, 11a).
Device (3) according to one of the claims 1 to 15, characterised in that the support element (13) exhibits a perimeter wall (13c) that is arranged around the full circumference at the edge of the lateral surface (13a), aligned essentially orthogonally to the lateral surface (13a) and connected to the lateral surface (13a) on a first end face.
Device (3) according to claim 16, characterised in that the cover element (14) is produced such that it can be arranged on a second end face of the perimeter wall (13c) of the support element (13) that is aligned with the first end face in such a way that it seals off the arrangement (5).
Device (3) according to claim 17, characterised in that a first sealing element (15) is arranged between the second end face of the perimeter wall (13c) of the support element (13) and the cover element (14).
Process for mounting the device (3) to drive a compressor of a vaporous fluid according to one of the claims 1 to 18, exhibiting the following steps:

- Premounting a power supply arrangement (5) as a modular component with

- Arrangement of at least one switching element (11, 11a) in a pass-through opening (13b) produced in a lateral surface (13a) of a support element (13), wherein connections of the switching element (11, 11a) project into a volume enclosed by the support element (13) with a cover element (14), and a surface of the switching element (11, 11a) passes through and projects out of the pass-through opening (13b),

- Attachment of the switching element (11, 11a), as well as

- Sealing of the arrangement (5) by the cover element (14), as well as

- Arrangement and attachment of the arrangement (5) to a housing (2) of the device (3), so that the surface of the switching element (11, 11a) that projects through and out of the pass-through opening (13b) of the support element (13) is in contact with a cooling surface of the housing (2).
Process according to claim 19, characterised in that when premounting the arrangement (5) at least one spring element (20) is applied to a contact surface produced (13d) on an edge of the pass-through opening (13b), itself produced in the support element (13), wherein the spring element (20) is arranged such that it projects into the pass-through opening (13b) and is connected to the support element (13).
Process according to claim 19 or 20, characterised in that when premounting the arrangement (5) a pre-assembled PCB (12) is connected to the support element (13).
Process according to claim 21, characterised in that connections of the switching element (11, 11a) are arranged such that they are plated through the PCB (12) and are connected to the PCB (12), wherein a spring element (20) is arranged between the PCB (12) and the switching element (11, 11a) and applies a pressure on the switching element (11, 11a) in the direction of the housing (2).
Process according to claim 22, characterised in that a mounting device (23) is used to move the switching element (11, 11a) into a mounting position in a direction (23a) towards the PCB (12) and against the direction of action of a compressive force generated by the spring element (20) and that the mounting device (23) is then removed after establishing the connections of the switching element (11, 11a) to the PCB (12).
Process according to claim 22 or 23, characterised in that when attaching the arrangement (5) to the housing (2) the switching element (11, 11a) is pressed against the cooling surface of the housing (2) on the surface aligned with the housing (2) as a result of the force applied by the spring element (20).
Use of a device to drive a compressor, in particular an electric motor, for compressing a vaporous fluid, according to one of the claims 1 to 18 for a compressor of a refrigerant in a refrigerant circuit of a motor vehicle air-conditioning system.