Air compressor for conveying air with channels formed in the housing

Abstract

The invention presented relates to an air compressor (100) for conveying air, wherein the air compressor (100) comprises: - a stator (101), and - a case (103), wherein the casing (103) surrounds the stator (101) and wherein the shell (103) comprises a number of channels (105) formed in the shell (103), and wherein the channels (105) overlap the stator (101) at least at the end face and form an air guide path (113) through the air compressor (100).

Description

[0001] The presented invention relates to an air compressor for conveying air, a manufacturing method for a stator of an air compressor, a stator for an air compressor and a fuel cell system according to the appended claims. State of the art

[0002] Air compressors for conveying air are usually designed as auxiliary units in a particularly compact manner for reasons of installation space.

[0003] Due to the compact design, thermal problems arise particularly in the area of ​​the stator of an electrical machine for driving an air compressor. Disclosure of the invention

[0004] Within the scope of the invention presented, an air compressor for conveying air, a manufacturing method for a stator of an air compressor, a stator for an air compressor, and a fuel cell system are presented. Further features and details of the invention emerge from the respective subclaims, the description, and the drawings. Features and details described in connection with the air compressor according to the invention naturally also apply in connection with the manufacturing method according to the invention, the stator according to the invention, and the fuel cell system according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made to each other.

[0005] The invention presented serves in particular to provide a possibility for robust operation of an air-conducting system, in particular a fuel cell system.

[0006] Thus, according to a first aspect of the invention presented, an air compressor for conveying air is presented.

[0007] The air compressor comprises a stator and a shell, wherein the shell surrounds the stator and wherein the shell comprises a number of channels formed in the shell, and wherein the channels overlie the stator at least at the front and form an air guide path through the air compressor.

[0008] In the context of the invention presented, an end face is understood to be a short side of a cylindrical stator.

[0009] In the context of the present invention, a casing is understood to mean a housing, in particular a housing with a bearing plate. Accordingly, the casing can include a bearing plate.

[0010] The presented invention is based on a casing in which a number of channels are formed. The channels overlap the stator at least at its end face, so that an air mass flow is guided along the stator through the channels. This means that the channels extend, in particular, over the entire length of the end face of the stator, in particular over the entire length of a short side of the stator, in particular over a winding head of the stator, so that the winding head is cooled by the cooling device at least at its end face.

[0011] Heat radiated by the stator is removed by an air mass flow flowing in the air guide path.

[0012] Due to the arrangement of the channels in the casing, the air compressor presented can be designed to be particularly compact.

[0013] To cool the stator or the winding head, the casing, particularly together with the stator or a stator casing, forms an air flow path that guides an air mass flow through the air compressor to areas of the stator subject to particularly high thermal stress, particularly to a winding head of the stator. Accordingly, thermal energy is transferred from the stator to the air mass flow and carried away, so that the stator is cooled and can be loaded with particularly high power.

[0014] The air guide path may comprise a number, in particular a plurality of partial air paths, each of which guides a partial air mass flow to a predetermined location of the air compressor.

[0015] To provide the air mass flow through the air guide path, ambient air can flow into the air guide path and be guided through the air guide path via convection, or a partial air mass flow of a main air mass flow provided by a turbine of the air compressor can be guided into the air guide path, so that the stator is cooled more intensively or dynamically as the air compressor power increases. For this purpose, the casing can comprise at least one inlet opening that introduces an air mass flow into the air guide path or respective channels and at least one outlet opening that discharges the air mass flow from the air guide path or respective channels.

[0016] Furthermore, for example, a partial air mass flow can be diverted after the compressor of the air compressor and optionally cooled beforehand, so that the air compressor is cooled more dynamically as the load and correspondingly increasing speed increase.

[0017] It can be provided that the channels are formed both on the front side along the winding head and laterally in the direction of the respective stator slots of the stator.

[0018] By superimposing the winding head on the front and sides by the channels formed in the shell, a surface for transferring thermal energy from an air mass flow flowing along the stator and the shell is maximized, so that thermal energy is transferred from the stator and the shell to the air mass flow, and the stator is protected from mechanical stress on the front and sides.

[0019] To provide the air mass flow through the air guide path, ambient air can flow into the air guide path and be guided through the air guide path via convection, or a partial air mass flow of a main air mass flow provided by a turbine of the air compressor can be guided into the air guide path, so that the stator is cooled more intensively or dynamically as the air compressor power increases. For this purpose, the casing can comprise at least one inlet opening that introduces an air mass flow into the air guide path and at least one outlet opening that discharges the air mass flow from the air guide path.

[0020] It can further be provided that a first number of channels is formed on the front side of the stator at a first end of the casing and a second number of channels is formed on the front side at a second front end of the casing opposite the first end.

[0021] Two channel arrangements or air guide paths at the respective ends of the housing running towards the stator provide a particularly high cooling capacity for tempering the stator, so that it can be subjected to a particularly high power.

[0022] It may further be provided that the air compressor comprises an interface for directing an air mass flow through the number of channels.

[0023] An interface, such as an intake or inlet duct, connects an air source, such as the surrounding air, to the air guide path, allowing an air mass flow to be guided through the air guide path to cool it. For this purpose, the interface can be connected, for example, via a supply duct to a partial air mass flow of a main air mass flow provided by a turbine of the air compressor, so that the stator is cooled more intensively or dynamically as the air compressor's power increases.

[0024] It can further be provided that the interface is configured to receive air guided through the channels from an environment and release it to the environment or to receive a partial air mass flow from a compressor and / or a turbine of the air compressor and release it to the turbine or an environment.

[0025] For this purpose, the interface can comprise an outlet or an outlet channel which guides an air mass flow heated by the stator out of the air compressor at a predetermined location which is thermally advantageous, ie, is subject to little thermal stress or is not very thermally sensitive.

[0026] It may also be provided that the casing is made of metal.

[0027] A metal shell is robust and can be easily formed, for example, using an injection molding process, along with the number of channels. Alternatively, the number can be added to the shell after the shell has been formed, for example, using a machining process.

[0028] It can further be provided that a number of air guiding elements are arranged on the casing in at least one air guiding path formed by the number of channels.

[0029] To guide an air mass flow flowing through the air guide path and / or to maximize heat transfer from the stator to the air mass flow, air guide elements such as cooling fins, undercuts, cavities, deflections and / or so-called pin-fin structures can be provided.

[0030] The air guiding elements can, for example, be provided together with the shell in a primary forming process or can be applied to the shell or incorporated into the shell.

[0031] According to a second aspect, the presented invention relates to a manufacturing method for a shell of an air compressor.

[0032] The presented manufacturing method comprises providing a shell for forming a housing for the air compressor, and forming a number of channels in the shell, wherein respective channels are configured to overlie a stator arranged in the shell at least at the front side and to flow around the stator with an air mass flow.

[0033] The provision of the shell and the formation of the number of channels can be carried out as an integrated manufacturing process together in one step, during primary forming of the shell of the stator.

[0034] Alternatively, the number of channels can be formed after the shell has been formed, for example by milling them into the shell.

[0035] Furthermore, it can be provided that the number of channels is formed by a shaping process from the following list of shaping processes: injection molding, transfer molding, machining processes, in particular milling.

[0036] It may further be provided that at least the number of channels is formed from a material from the following list of materials: silicone, thermoplastic, duroplastic.

[0037] Channels made of silicone, thermoplastic or thermoset have an electrically insulating effect and can be manufactured particularly cost-efficiently.

[0038] According to a third aspect, the presented invention relates to a cover for an air compressor, wherein the cover is produced by a possible embodiment of the presented manufacturing method.

[0039] The presented shell is characterized in particular by channels running along its front sides for guiding an air mass flow.

[0040] According to a fourth aspect, the presented invention relates to a fuel cell system for converting energy.

[0041] The presented fuel cell system comprises a fuel cell stack and a possible design of the presented air compressor for supplying the fuel cell stack with air.

[0042] Due to the air compressor presented, which can be subjected to particularly high loads, the fuel cell system presented is particularly powerful, robust and particularly compact.

[0043] Advantages described in detail for the air compressor for conveying air according to the first aspect of the invention equally apply to the manufacturing method for a shell of an air compressor according to the second aspect of the invention, to the shell for an air compressor according to the third aspect of the invention, and to the fuel cell system for converting energy according to the fourth aspect of the invention.

[0044] Further advantages, features, and details of the invention will become apparent from the following description, which describes embodiments of the invention in detail with reference to the drawings. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination. They show: Fig. 1 a schematic representation of a possible design of the presented air compressor in a sectional side view, Fig. 2 a plan view of a stator of the air compressor according to Fig. 1, Fig. 3 a possible design of the presented fuel cell system, Fig. 4 a possible design of the presented manufacturing process.

[0045] In Fig. 1 shows an air compressor 100 for conveying air. The air compressor 100 includes a stator 101, a casing 103, and a number of channels 105 formed in the casing 103.

[0046] The stator 101 comprises a winding head 107 and a casing 109 made of a plastic, such as a resin, which surrounds at least the winding head 107.

[0047] The channels 105 overlie the stator 103 in this case at its end face 111 and, together with the casing 109, form an air guide path 113 which is configured to guide an air mass flow along the stator 101, as indicated by arrows 115 and 117.

[0048] In Fig. 2, the stator 101 is according to Fig. 1 is shown in a top view. Here, inlets 119 and 121 for the air mass flow into the air guide path 113 are visible.

[0049] The air mass flow is guided through air guiding elements 123 to the winding head 107 and through an inner part 125 of the stator 101.

[0050] In the present case, the air guide path 113 comprises a main region 127 which extends radially around an inlet region in the inner part 125 of the stator 101 and a number of secondary regions 129 which connect the main region 127 in an air-conducting manner to the inlet region in the inner part 125 or to the inner part 125 itself.

[0051] In this case, a movement of an air mass flow directed into the interior region 125 is influenced by a shape of the respective air guiding elements 123 forming the secondary regions 129, for example by swirling it.

[0052] In Fig. 3 shows a fuel cell system 300 for converting energy.

[0053] The fuel cell system 300 comprises a fuel cell stack 301 and an air compressor 100 according to Fig. 1 for supplying the fuel cell stack 301 with air.

[0054] In Fig. 4 shows a manufacturing method 400 for producing a possible embodiment of the presented air compressor.

[0055] The manufacturing method 400 includes a provision step 401 in which a shell is provided, for example, by casting the shell in a casting process. The shell 103 forms a housing for the air compressor.

[0056] Furthermore, the manufacturing method 400 includes a forming step 403 in which a number of channels are formed in the shell. The forming step 403 and the provision step 401 can be performed simultaneously, as an integrated manufacturing method 400, or sequentially, for example, by milling the number of channels into the shell 103.

[0057] The channels are configured to overlie a stator arranged in the casing at least at the front side and to flow around the stator with an air mass flow.

Claims

[1] Air compressor (100) for conveying air, wherein the air compressor (100) comprises: - a stator (101), and - a cover (103), wherein the shell (103) surrounds the stator (101) and wherein the shell (103) comprises a number of channels (105) formed in the shell (103), and wherein the channels (105) overlie the stator (101) at least at the front and form an air guide path (113) through the air compressor (100). [2] Air compressor (100) according to claim 1, characterized by that respective channels (105) are formed both at the end face along a winding head (107) of the stator (101) and laterally in the direction of respective stator slots of the stator (101). [3] Air compressor (100) according to one of the preceding claims, characterized bythat a first number of channels (105) is formed on the end face of the stator (101) at a first end of the casing (103) and a second number of channels (105) is formed on the end face at a second end of the casing (103) opposite the first end. [4] Air compressor (100) according to one of the preceding claims, characterized by that the air compressor (100) comprises an interface for directing an air mass flow through the number of channels (105). [5] Air compressor (100) according to claim 3, characterized by that the interface is configured to receive air guided through the channels (105) from an environment and release it to the environment or to receive a partial air mass flow from a compressor and / or a turbine of the air compressor and release it to the turbine or an environment. [6] Air compressor (100) according to one of the preceding claims, characterized bythat a number of air guiding elements (123) are arranged on the casing (103) in at least one air guiding path (113) formed by the number of channels (105). [7] Manufacturing method (400) for a shell (103) of an air compressor (100), the manufacturing method (400) comprising: - Providing (401) a shell (103) for forming a housing for the air compressor (100) - forming (403) a number of channels (105) in the casing (103), wherein respective channels (105) are configured to overlie a stator arranged in the casing (103) at least at the front side and to flow around the stator with an air mass flow. [8] Manufacturing method (400) according to claim 7, characterized by that the number of channels (105) are formed by a shaping process from the following list of shaping processes: Injection molding, transfer molding, machining processes, especially milling. [9] A shell (103) for an air compressor (100), wherein the shell (103) is manufactured by a manufacturing method (400) according to claim 7 or 8. [10] Fuel cell system (300) for converting energy, the fuel cell system (300) comprising: - a fuel cell stack (301), - an air compressor (100) according to one of claims 1 to 7 for supplying the fuel cell stack (301) with air.

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