Patent Description:
Housings for electronic components preferably include a plurality of feedthroughs in order to guide wires from outside to the inner part of the housing, which accommodates e. parts of an electronic compressor in the housing. Housing parts comprising at least one conductor fed through an opening into a housing suffer from a low bending stiffness. Further the pressure resistance of housing parts according to the state of the art was low. The positioning of the housing parts, especial e-compressor terminals have been difficult. Also the evenness and the sealing in the state of the art was defective, and their long-term reliability deserves improvement. The defectiveness of the evenness especially arises when a spigot is used for centering the housing component or the so called GTMS plate to a housing which accommodates electric compressor and the spigot was situated in the center of the GTMS plate or the housing component.

The document <CIT> discloses an electrical terminal for a compressor being attached to the outer surface of the housing.

The document <CIT> discloses a holder for electric conductors with the conductors being embedded in a glass ceramic material, the holder to be attached to a compressor housing.

It is therefore the objective of the current invention to overcome the disadvantages of the state of the art.

In particular, a housing part should be specified which is characterized having a high stiffness and pressure resistance. Further an improved centering of the housing part, especially the glass metal plate comprising the feedthroughs to a housing with a high flatness should be possible.

A housing part according to the invention comprises at least one opening for at least one conductor embedded in a glass or a glass ceramic material that is fed into each of the respective openings providing a glass-metal seal (GTMS). The term GTMS also comprises glass ceramic materials and the like. As generally known, those represent a group of inorganic materials which are capable of electrically insulating the conductor from the housing part and to seal the openings.

According to the invention, the aforesaid objective is achieved in that said housing part or housing component, in particular for a housing, preferably an e-compressor housing, comprises a structure for centering the housing part at a structure of the housing to which the housing part is to be attached. Such structure for centering is according to the invention represented in a first alternative by a recess area. In a second alternative this can be a protrusion. The housing part can be affixed to the structure by screws in at least two bores, e.g. screw bores at the edge of the GTMS plate or housing part. The housing part, especially e-compressor terminal according to the invention furthermore comprises a structure for enhancing the housing parts resilience against bending, or with other words, enhances the stiffness of the housing part, especially the e-compressor terminal. This structure or structures for enhancing the housing parts resilience against bending are represented e.g.by at least one pulled up edge. By the recess and the pulled up edge the stiffness and the sealing capabilities, especially the pressure resistance and/or long-term sealing reliability of the housing part in a first alternative, can be significantly improved. The pulled up edge could surround the complete edge of the housing part, e.g. the GTMS plate or only a part of the edge, e.g. the central part.

The enhancement of the stiffness, especially the bending stiffness which leads to a higher compression onto the glass or glass-ceramic material through which a conductor is fed by the housing part are the following:.

especially a structural steel in form of a micro alloyed steel.

By the higher compression of the housing material, especially in the region of the opening for the feedthrough a tight sealing can be provided. A tight sealing according to this application means that the helium leakage rate is lower than <NUM>-<NUM> mbar l/sec for a pressure difference of <NUM> bar. The structural steel which most preferred is used comprises Ni, Nb, Ti, Al, V as alloy components. The stiffness is increased by <NUM> to <NUM>% if such a material is used for the housing part. Structural steel is normally a carbon steel. If the stiffness can enhanced by one or more of the above mentioned measurement e.g. using a structural steel in form of microalloyed steel and/or providing a recess then the thickness of the housing part can be reduced without the compression e.g. onto a glass material of a feedthrough being effected. The usage of microalloyed steel as material has several advantages. One further advantage beside the high stiffness is the fact that a body of microalloyed steel in contast to normal structural steel has a lower weight. This is due to the fact that because of the high stiffness and yield strength of microalloyed steel, the wall thickness of the body can be reduced. The yield strength and therefore the stiffness of normal steel is reduced when e.g. the conductor is brought in or glassed into a glass or glass ceramic material due to the high temperature of this process. The yield strength of microalloyed steel is not so prominent reduced by high temperatures. Therefore the yield strength and therefore stiffness of microalloyed steel is significantly higher after a temperature glassing process compared to that of a normal steel. The higher yield strength and therefore stiffness then can result in a higher compression of the metal onto the glass or glass-ceramic material. Furthermore the higher yield strength and therefore stiffness is advantageous for the housing part because it then can better withstand the pressure load from inside the housing onto which the housing part is mounted. A leaking between the housing part and the housing is prevented by the stiffer housing part.

The term structure in the meaning of this disclosure covers all means, especially all geometrical means, which are attached and/or formed-in at the housing part which is subject to the invention.

The above mentioned advantages are especially beneficial for a preferred embodiment of the housing part, in which the housing part represents an elongated structure. This means that the housing part is longer than wide, beneficially a multiple times longer than wide. This especially is the case for embodiments which comprise a plurality of openings, which means more than one opening. Such elongated structures are especially prone to bending issues.

In a preferred embodiment the recess area can be formed by using a stamping and/or reforming process. Thereby the housing part, specifically the base of the housing part, and the recess area are a one-piece part. Or with other words, the recess area is formed from the base of the housing part, elevating over or under the plane of the base.

Such a production process is cheap and can be easily performed especially for a plate like housing part. The reforming and/or stamping has the further advantage, that there is no bonding line between the base area and the recess area of the housing part, which could have effects on the long-term stability of the finished housing part. It has to be taken into account that especially in the e-compressor application the housing part is exposed to temperature changes over a large interval of temperatures, temperature shocks and/or vibrations. Any existing mechanical connection between separate parts, in this case the base area and the recess area, could induce mechanical stress and therefore also deformation into the recess area, which normally has the function to seal the housing to which the housing part is attached. Any deformation could lead to a loss of sealing capabilities and therefore might reduce the long-term reliability of the interconnection of the housing and the attached housing part.

The recess area represents a plane which is elevated from the plane of the base of the housing part. Thereby the recess area has a side wall which extends from the base of the housing part. In an especially preferred embodiment, the transition of the base of the housing part and the side wall is rounded, preferably with a radius R. This helps to enhance the mechanical long term stability of the housing part, since the housing part is normally made of metal, and the rounded transition especially together with the one-piece design reduces the risk of the formation of initial cracks of the metal structure. The value of R can of course be dependent on the overall dimensions of the housing part. In a common application for an e-compressor, R is advantageously between <NUM> and <NUM>,<NUM>.

It is foreseen and covered by the invention that the side wall can be perpendicular to the plane of the base of the housing part, but could also be in another angle or sloped, in order to be pressed in or to be even better centered into the structure of the housing to which the housing part is attached.

According to an embodiment of the invention, the pulled up edge could be a separate part, which could be joined with the plate like element of the housing part by fusing. The advantage of the pulled up part to be a separate part is that production of both parts - plate like element and pulled up part - could be organized separately. Because the pulled up edge is attached to the base part of the housing and therefore away from the sealing area, the bondline between the pulled up edge and the base of the housing part is assumed not to interfere with the long term sealing capabilities of the recess area as discussed above.

However, in an alternative embodiment, the housing part is reshaped in order to provide the pulled up edge. Such a reshaping process could be e. stamping the plate like element in order to provide a recess. This reforming and/or reshaping again leads to a one-piece part with all the advantages caused by the absence of a mechanical bondline as discussed above.

In a most preferred embodiment the recess area has, at least at the side to be connected to the housing, a flatness according to DIN ISO <NUM> of at least <NUM>, preferably at least <NUM>,<NUM>, most preferably from <NUM> to <NUM>. As discussed earlier, the recess area serves to seal the housing from the environment. Therefore a good flatness can be achieved by the aforesaid structures, i.e. the recess area which represents a one-piece part and the pulled up edges, and this flatness is achieved during operations and a long term period of time. Therefore, the recess area and the pulled up edge work together to achieve those beneficial behavior. This also allows to reduce the thickness of the housing part and thereby to reduce the amount of material needed. This helps to reduce the overall weight and therefore to increase the efficiency of e.g. vehicles which comprise an e-compressor with the inventive housing.

In order to provide a gas tight glass-to-metal seal, it is advantageous if at least one conductor and the glass or glass ceramic material form a compression seal. With a compression seal it is possible to provide a hermetical seal. Specifically, a He leakage rate of better then <NUM>*<NUM>-<NUM> mbar l/min can be achieved by a compression seal. The term compression seal is commonly known. It generally means that the thermal expansion of the glass or glass ceramic material is smaller than the thermal expansion of the surrounding material, so that, as the glass or glass ceramic material solidifies when it is melted in, the surrounding material so to say 'shrinks' onto the glass or glass ceramic material and thereby exerts a permanent compressive stress on the glass or glass ceramic material, which improves the mechanical pressure resistance.

In a most preferred embodiment the housing part comprises as a material steel, especially stainless steel, most preferred structural steel, preferably microalloyed steel, most preferred structural steel in form of microalloyed steel. Microalloyed steel is a type of alloy steel that contains small amounts of alloying elements (<NUM>,<NUM> to <NUM>,<NUM> %), including niobium, vanadium, titanium, molybdenum, zirconium, boron and rare-earth metals. They are used to refine the grain microstructure or facilitate precipitation hardening. The yield strength of microalloyed steel is between <NUM> and <NUM> MPa without heat treatment. Weldability is good, and can even be improved by reducing carbon content while maintaining strength. Fatigue life and wear resistance are superior to similar heat-treated steels. Cold-worked microalloyed steels do not require as much cold working to achieve the same strength as other carbon steel; this also leads to greater ductility. By using microalloyed steel as material, a high bending stiffness and strength could be provided. The advantages of the usage of a microalloyed steel instead of a normal or structural steel is described before in the application.

In an alternative embodiment in order to position and/or mount the housing part to the housing, e.g. when used for an electric compressor, the housing part can comprise at least a protrusion. For mounting the housing part to the housing the housing part can comprise at least one attachment bore such as a screw bore. In a preferred embodiment the GTMS plate comprises two attachment and/or screw bores at the edges of the GTMS plate or the housing part.

In a preferred embodiment, the housing part has, in the area of the elevated plane of the recess area, a structure, which advantageously enhances the surface area. This structure preferably is a stamped-in and/or reformed structure. Most preferably, the structure has an undercut. This can be achieved by stamping and subsequent reforming.

In a preferred embodiment the housing part comprises in the area of the openings a plastic material. The plastic material serves as further electrical insulation of the conductors which are fixed in the openings. This plastic can also contribute to reduce the risk of short currents, especially in case of wet or humid surroundings, when a water layer and/or dirt layer or the like might deposit on the surface of the glass or glass ceramic material. Since the openings are within the recess area, this means that the surface of the recess area can encompass said structures, specifically the surface at the outer side of the housing.

Most preferably, at least a part of the structure of the elevated plane of the recess area has a roughness e.g. provided by a stamping or a embossing process for a casting compound which connects metal to an adhesive. Due to the good adhesion a save connection between the metal material and a plastic material is provided.

The housing can comprise opposite to the opening or the screw bores for centering the housing part, especially the GTMS plate, a bushing attached to the housing or the housing part, e.g. by welding or brazing.

The inventive housing part or GTMS plate with a recess area and/or a screw bore and/or protrusions can be used for an e-compressor terminal. The e-compressor terminal is used in an electric compressor. Electric compressors or e-compressors are widely used in environmentally friendly vehicles to support the operation of the air conditioning system. Electric and hybrid vehicles are equipped with battery powered electric compressors. The electric compressors must be hermetically sealed and function with their own motor inside. E-Compressor terminals or feedthroughs are important components of electric compressors and must be designed and manufactured carefully for optimal performance. An e-compressor terminal enables the transfer of large amounts of energy from the battery to the air conditioning compressor, and at the same time must remain reliably gas-tight to prevent refrigerant leakage. Electric compressors have very high performance and durability requirements while also being subjected to harsh environmental conditions. These include high pressure, high humidity and vibration. Compressor terminals or feedthroughs must be able to withstand such adverse conditions without issue. Highly controlled and precise processes are necessary to provide long-term reliable gas-tightness. Moreover, the compressor terminals must deliver extremely high insulation resistance and high voltage capabilities to support future quick-charging technology developments. High current capabilities are also essential to enable upcoming 48V electrical systems. This can be achieved with the inventive housing part when used in an e-compressor as an e-compressor terminal.

The above mentioned and other features and advantages of this invention and the manner of attaining them will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taking in conjunction with the accompanying drawings wherein:.

The inventive housing part is preferably an e-compressor terminal. E-compressor terminals are important components of electric compressors and must be designed and manufactured to enable the transfer of large amounts of energy from the battery to the air conditioning compressor and at the same time remain reliably gas-tight to prevent any leakage, especially of refrigerant. Furthermore, electric compressors are effected by high pressure, high humidity and vibration.

Compressor terminals must be able to withstand such adverse conditions. Furthermore, a compressor terminal must have extremely high insulation resistance and high voltage capabilities for e. 48V electrical systems.

<FIG> is a cross-sectional view of a housing part <NUM>, especially in a plate like form, which can be used as an e-compressor terminal with three conductors, <NUM>, <NUM>, <NUM>, fed through three openings, <NUM>, <NUM>, <NUM>. All three conductors <NUM>, <NUM>, <NUM> are fed through the openings <NUM>, <NUM>, <NUM> in a glass or glass ceramic material <NUM>, <NUM>, <NUM>. The glass or glass ceramic material <NUM>, <NUM>, <NUM> comprises for example a soda barium glass.

The material of the conductors <NUM>, <NUM>, <NUM> can, for example, be Cu, cored Fe-Cr, copper or Fe-Cr. The material of the housing part or the housing component is preferably steel, especially structural steel or stainless steel, most preferably micro alloyed steel. The usage of micoalloyed steel as material has several advantages. One advantage is the higher stiffness and the higher yield strength. Furthermore a body of microalloyed steel provides for a lower weight then normal steel due to thinner wall thicknesses. Also under temperature e.g. in a glassing process the yield strength and therefore stiffness of microalloyed steel is not so prominent reduced as in the case of structural steel.

The inventive housing part <NUM> as shown in <FIG> further comprises two bores, especially screw bores <NUM>, <NUM>, comprising a screw <NUM> which is used for mounting and/or positioning the housing part, especially the e-compressor terminal in relation to the housing of the e-compressor. The centering of the housing to the housing part of the e-compressor terminal is provided by the two protrusions <NUM>, which are part of the compressor housing. The housing also comprises two bores as well as the housing part.

Attached to the housing part are two bushings <NUM>, <NUM> with a thread into which screws <NUM> are screwed. By this measurement the housing part, especially the e-compressor terminal can be attached to the housing, especially the compressor housing e.g. by screws.

The bushings <NUM>, <NUM> are welded in a gas-tight manner to the housing and/or housing part, especially the e-compressor terminal.

<FIG> shows in detail the housing and the housing part <NUM> in form of an e-compressor terminal with one of the two bores, especially screw bores <NUM> at each side of the GTMS plate <NUM> through which a screw <NUM> is fed into the bushing <NUM>. The bushing <NUM> is welded to the housing and/or housing part in an air-tight manner. A screw <NUM> is feed through each of the screw bores <NUM> of the housing part <NUM> and fastened in said bushing so that the housing part, especially the e-compressor terminal <NUM> is fixed to the housing, especially the compressor housing15 comprising the compressor tightly. As in <FIG>, the housing <NUM> is centered to the housing part by protrusions <NUM> of the housing. The housing part is fastened to the housing by a screw <NUM> in the bore <NUM>.

<FIG> shows a top view of a housing part of an e-compressor to which the housing, especially the e-compressor housing is attached. Clearly can be seen the screw bores <NUM>, <NUM> as well as the three openings <NUM>, <NUM>, <NUM> through which the conductors <NUM>, <NUM>, <NUM> of the compressor terminal are fed. Through the screw bores screws are fed e.g. to a bushing and the housing part, especially e-compressor terminalis securely fixed to the housing, especially the e-compressor housing.

Further shown in <FIG> is an area <NUM> with a surface having a roughness for an adhesive or a casting compound to adhere a plastic material to the metal of the e-compressor terminal. The roughness can be provided by stamping or a embossing process. The area <NUM> is adjacent to the three conductors <NUM>, <NUM>, <NUM> and provides for a better connection of a plastic material and the e-compressor terminal, which normally comprises a metal such as steel, stainless steel, preferably a structural steel especially a structural steel preferably in form of a microalloyed steel.

<FIG> is a cross sectional view through a housing part in a second embodiment of the invention with two bores and two protrusions <NUM>, <NUM>, which fit e.g. into two bores of the housing. The protrusions serve only for centering the housing components to the housing comprising the e-compressor but not attaching the same to the housing e.g. by screws. The screw bores are separate from the centering bores as shown in <FIG>.

In <FIG> the screw bores are denoted with reference number <NUM> and <NUM> and the protrusions with <NUM> and <NUM>. As the embodiment of <FIG> the housing part comprises three conductors <NUM>, <NUM>, <NUM> fed through three openings <NUM>, <NUM>, <NUM> of the housing part <NUM>. As in <FIG> the housing part is in a plate like form but comprises edges in a pulled up form, so called pulled up edges <NUM>. By the pulled up edge <NUM> the housing part provides for a higher stiffness and a higher pressure resistance. The pulled up edge <NUM> in the embodiment in <FIG> surrounds the whole plate like element, especially the e-compressor terminal with the opening <NUM>, <NUM>, <NUM> through which the conductors <NUM>, <NUM>, <NUM> are fed. As can be seen from <FIG> the plate like part of the housing part, especially the e-compressor terminal and the pulled up edge <NUM> of the housing part are a one part element. This is possible if the pulled up edge is formed e.g. by a stamping or a forming process out of the plate like element.

Stamping or forming is a very cheap process for forming the pulled up edge <NUM>. The height H of the pulled up edge <NUM> is preferably between <NUM> and <NUM>, most preferred <NUM>. The thickness D of the plate like element is between <NUM> and <NUM>, preferred <NUM>,<NUM> and <NUM>,<NUM>, most preferred
<NUM>,<NUM>. Each of the conductors <NUM>, <NUM>, <NUM> is fed through each of the openings molten in a glass material <NUM>, <NUM>, <NUM> which provides for a gas tight sealing, a so called pressure sealing.

<FIG> shows a different embodiment of the invention also in a cross-sectional view. The e-compressor terminal or housing part shown in <FIG> has a pulled up edge <NUM> and a recess <NUM> formed into the plate like element <NUM> by e.g. a stamping process. In contrast to the embodiment of <FIG> the pulled up edge is only in the central part of the plate like element of <FIG> as shown in <FIG>.

As can be seen in <FIG>, this embodiment also comprises three openings <NUM>, <NUM>, <NUM>, through which conductors are fed. Further, as in <FIG>, the plate like element comprises two bores <NUM>, <NUM>, through which a screw can be fed in order to position and fix the housing part, especially the e-compressor terminal to a housing, especially an e-compressor housing. The screw is not shown in <FIG>. The screw bores of the embodiment in <FIG> is not necessary for the centering of the housing part to the housing, e.g. the compressor housing. The centering is made in this embodiment by the recess area of the housing part or the GTMS plate. The screws are only needed to fix the housing part to the e-compressor housing. Therefore the screw are beneficial, but not necessary.

The direction of stamping the plate like element is denoted by <NUM>. By stamping the plate like element, the recess <NUM> can easily be formed. The recess <NUM> is used for a centering of the housing part especially the plate like element or e-compressor terminal in relation to the e-compressor housing.

By the pulled up edge as well as the recess area the stiffness of the plate like element could be enhanced. As can bee seen from <FIG>, which shows another cross section of the plate like element or the housing part, the complete housing part can be formed by a forming process, comprising inter alia stamping of the recess as well as forming the pulled up edge <NUM>.

As described before the recess and the pulled up edge, the housing part, especially for an e-compressor, can provide for a higher stiffness and a higher pressure resistance.

In <FIG> the same numbers are used for the same elements as in <FIG> shows the pulled up edge <NUM> as well as one opening <NUM> through which a conductor is fed. As material for the housing part, especially for an e-compressor terminal, steel is used. A stiffness about more than <NUM>-<NUM>% higher than in common systems is reached, in case as a material for the housing part, a micro alloyed steel is used. Instead of the micro alloyed steel also normal steel or stainless steel can be used.

<FIG> is a lower view of the housing part of <FIG>, especially for an e-compressor terminal. Equal elements as in <FIG> are denoted with the same reference numbers. In <FIG> clearly shown are the three openings <NUM>, <NUM>, <NUM> as well as the bores <NUM>, <NUM> through which screws for mounting the housing part to the housing e.g. of an e-compressor are shown. In <FIG> the three openings <NUM>, <NUM>, <NUM> are surrounded by a seal area <NUM>. In the seal area <NUM> a surface seal between the housing part, especially the e-compressor terminal and the housing, especially the e-compressor housing is provided. By the seal in the sealing area the e-compressor terminal or housing part can connected to the e-compressor housing in a thight manner.

<FIG> shows the housing of an e-compressor, in an upper view onto which the housing part is attached. All three openings <NUM>, <NUM>, <NUM> for the conductors can be seen. Further to the openings <NUM>, <NUM>, <NUM>, two bores for screws in order to attach the housing part, especially the e-compressor terminal, to the housing of an e-compressor, is shown and denoted with reference number <NUM>, <NUM>. Each bore comprises an area <NUM>, <NUM> which surrounds the bores <NUM>, <NUM>. These areas are flatness areas for the screw heads of the screws which are fed into the bores. The flatness areas prevent that the screws are fitted.

<FIG> denotes a 3D-picture of the e-compressor terminal. What could be seen quite clear is the pulled up edge, which provides for a higher stiffness of the element. Further as is apparent from <FIG> the pulled up edge <NUM> of the embodiment of <FIG> does not surround the whole plate like element like in <FIG> but only the central part. Even if the pulled up edge is concentrated to the central part as in the embodiment of <FIG> the stiffness of the plate like element can be enhanced sufficiently. The e-compressor terminal of <FIG> can be commended in a thight manner to the housing of the e-compressor.

The same components as before are denoted with the same number.

Claim 1:
Electric compressor housing part (<NUM>) in form of a plate like element with at least one opening (<NUM>, <NUM>, <NUM>) for
at least one conductor (<NUM>, <NUM>, <NUM>) embedded in a glass or a glass ceramic material (<NUM>, <NUM>, <NUM>) that is fed into into the at least one opening providing a glass-metal seal (GTMS)
wherein
said electric compressor housing part (<NUM>) comprises means for centering the electric compressor housing part (<NUM>) within a structure of a housing and means for enhancing the resilience against bending, wherein the means for centering the electric compressor housing part (<NUM>) are represented by a recess area (<NUM>) and/or at least two bores (<NUM>, <NUM>)
characterized in that
the electric compressor housing part (<NUM>) comprises an area (<NUM>) with a roughness provided by stamping or an embossing process for a casting compound and/or an adhesive and an area (<NUM>) which provides for a seal between the electric compressor housing part (<NUM>) and the housing.