Method for manufacturing rotors for fluid pumps

Abstract

The invention relates to a method (100) for manufacturing rotors (14) for fluid pumps (10), wherein each rotor (14) has at least one rotor body (18) and a vane wheel (16) connectable to it, comprising at least the following method steps: - Marking (110) the individual impellers (16) with an imbalance classification (200), - Determining (120) the imbalance of a rotor body (18), - Identifying (130) an imbalance classification (200) reducing the imbalance of the rotor body (18), - Connecting (140) a rotor wheel (16) with corresponding imbalance classification (200) to the rotor body (18).

Description

State of the art

[0001] Rotors for fluid pumps with integrated balancing elements are already known. The imbalance is usually caused by slightly asymmetrical active components, such as the vane stack or the magnets of the rotor body. Rotors known from the prior art are balanced by mounting a balancing element. These balancing elements are generally expensive. Disclosure of the invention

[0002] The invention relates to a method for manufacturing rotors for fluid pumps, wherein each rotor has at least one rotor body and a vane wheel connectable to it, comprising at least the following process steps: - Marking each impeller with an imbalance classification - Determining the imbalance of a rotor body - Identifying an imbalance classification that reduces the imbalance of the rotor body - Connecting a rotor wheel with the appropriate imbalance classification to the rotor body.

[0003] The inventive method for manufacturing rotors has the advantage that the rotor bodies can be specifically connected to a rotor wheel that is matched to the imbalance of the rotor body in order to reduce the imbalance. In this way, additional elements, such as additional balancing clips, can be omitted. This has a particularly advantageous effect on the cost of such a rotor. Furthermore, no additional installation space needs to be provided for these balancing elements and their assembly, especially between the rotor body and the rotor wheel, so that the present invention positively influences the required installation space of the rotors.

[0004] Bodies of revolution always possess a so-called imbalance, which arises because the body's mass is not distributed with sufficient rotational symmetry about an axis of rotation. Imbalances lead to vibrations, increased wear, and acoustic excitation, which is why they can be compensated for by adding weight or removing material; i.e., the body of revolution is balanced. A typical example of this is the wheels of a motor vehicle. A general distinction is made between static and dynamic imbalance, although both forms usually occur simultaneously.

[0005] Static imbalance arises when the axis of rotation of a rotating body does not pass through its center of gravity. It is a special case of dynamic imbalance. A characteristic of static imbalance is that the plane in which the imbalance lies coincides with a radial plane of the rotating body's center of gravity, thus generating circular mechanical vibrations perpendicular to the axis of rotation when the body rotates parallel to the radial plane. Dynamic imbalance arises when the axis of rotation does not coincide with one of the (stable) principal axes of inertia of the rotating body. In this case, the axis of rotation is tilted at the center of gravity of the rotating body. Dynamic imbalances only occur during operation of the possibly composite rotating body. They manifest as a bending moment, the so-called imbalance moment, with respect to the axis of rotation. They cause circular vibrations at the ends of the axis that are shifted by 180°, which are absorbed by one or two bearings.must be compensated. The center of gravity of the rotating body remains at rest, while the axis of rotation wobbles due to the opposing circular motions.

[0006] This form of imbalance is often perceived as a “fluttering” sound in the wheels of a vehicle, for example.

[0007] For fluid pump rotors in vehicle cooling and / or refrigerant circuits, increasingly stringent requirements are being placed on imbalance, particularly regarding dynamic imbalance in addition to the conventional maximum static residual imbalance. In a fluid pump rotor, both the rotor body and the impeller attached to the rotor body contribute to the rotor's dynamic imbalance. This rotor imbalance can be corrected to a certain degree using this method.

[0008] It is an object of the invention to provide an improved method for arranging a vane wheel on a rotor body, so that the imbalance of the overall rotor assembly is advantageously reduced.

[0009] The imbalance of the rotor can be reduced particularly easily and cost-effectively using the method according to the invention. Preferably, the impellers and the rotor base are manufactured separately, their imbalances are adjusted, and then the impeller and rotor base are joined, in particular pressed together. The impellers can also be designed as paddle wheels.

[0010] The separately manufactured impellers are preferably intentionally designed with an imbalance. It is advantageous to produce one type of impeller without significant imbalance and two further types of impellers with progressively increasing imbalance. The impellers with the imbalance classification best suited to the determined imbalance of the rotor body can then be specifically selected and preferably pressed onto the rotor at the optimal angular position. Preferably, a large number of impellers are manufactured, each with a predefined imbalance classification. The impellers are preferably marked with an imbalance indicator that corresponds to the imbalance classification, particularly the predefined one. The imbalance indicator of the impeller can specify, in particular, the magnitude, position (especially the angular position), and / or direction of the predefined imbalance. Preferably, the imbalance indicator is a Data Matrix code.

[0011] A particularly simple procedure can be provided by including at least three predefined imbalance classifications, wherein the first imbalance classification corresponds to a classification of impellers without significant imbalance, and wherein each subsequent imbalance classification has an increased, preferably stepwise, imbalance compared to the previous imbalance classification.

[0012] To facilitate joining the rotor base body and the selected impeller of a corresponding unbalance classification, it may be advantageous for the impeller's unbalance marking to indicate the location of the imbalance. This allows the impeller to be pressed onto the rotor base body at the appropriate angular position.

[0013] According to an advantageous embodiment of the invention, the impellers can be manufactured by selectively arranging balancing elements and / or balancing recesses on the impeller with their corresponding imbalance classification. Preferably, the balancing element and / or the balancing recess is produced by projections or recesses in the injection mold, so that the balancing elements and / or recesses are injection-molded.

[0014] According to an advantageous development of the invention, the impellers each have a base body, a cover plate and preferably a bearing bush, wherein the balancing elements and / or balancing recesses are arranged on the base body and / or the cover plate and / or preferably the bearing bush. drawing

[0015] Further advantages will become apparent from the following description of the drawings. The drawings illustrate two exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.

[0016] They show: Fig. 1 A schematic representation of a rotor, Fig. 2 a schematic representation of a process for manufacturing rotors, Fig. 3. An example of a breakdown of imbalance classifications. Description of the exemplary implementations

[0017] Fig. Figure 1 shows a rotor 14 of a fluid pump 10. Such a fluid pump 10 can, for example, be used as a water pump in a cooling circuit of a motor vehicle. As an auxiliary water pump, the fluid pump 10 can also be used to cool charge air, a battery, a control unit, or other components of the motor vehicle.

[0018] According to the Fig. In the embodiment of the invention shown in Figure 1, the rotor 14 comprises a vane 16 and a rotor body 18. The rotor body 18 preferably has a rotor shaft 20. According to a preferred embodiment of the invention, a laminated core 22 is arranged on the rotor shaft 20, which preferably consists of a plurality of stamped sheets 24 joined to form the laminated core 22.

[0019] According to the Fig. In the embodiment of the invention shown in Figure 1, a plurality of magnets 24 are arranged distributed around the outer surface of the lamination stack 22. It is conceivable that a casing 25 is arranged around the magnets 24, which encloses the rotor body 18. It is also conceivable that the magnets 24 are overmolded with plastic. The magnets 24 can be either hard ferrite magnets or neodymium magnets. After the impeller 16 is mounted on the rotor shaft 20, the rotational movement of the rotor body 18 is preferably transmitted to the impeller 16.

[0020] According to an advantageous embodiment of the invention, the impeller 16 comprises a base body 30, a cover plate 32, and a bearing bushing 34. Impeller blades 36 are preferably arranged between the base body 30 and the cover plate 32. The impeller blades 36 can be formed as part of the cover plate 32 and / or the base body 30. The bearing bushing 34 is designed to be mounted on the rotor shaft 20 of the rotor base body 18. The rotor base body 18 preferably has a bearing 40 for supporting the rotor 14 in the fluid pump 10. The rotor base body 18 is designed as an active component and, due to the manufacturing process, typically exhibits an imbalance. This imbalance can be determined in existing manufacturing equipment.

[0021] The impeller 16 is manufactured as a separate component and mounted on the rotor base body 18. According to the invention, to reduce the imbalance of the rotor 12, the impellers 18 are first marked with an unbalance classification 200. The unbalance of the rotor base body 18 is then determined, and an unbalance classification 200 that reduces the unbalance of the rotor base body 18 is identified, and an impeller 16 of this unbalance classification 200 is connected to the rotor base body 18. For this purpose, according to an advantageous development of the invention, a plurality of impellers 16, each with a predefined unbalance classification 200, are manufactured. To produce impellers 16 with a predefined unbalance classification 200, according to an advantageous development of the invention, balancing elements 240 and, alternatively or additionally, balancing recesses 242 can be arranged on the impellers according to the unbalance classification 200.The balancing elements 240 and / or balancing recesses 242 are preferably designed to create a specific imbalance in the impeller 16. The balancing elements 240 can, for example, be material accumulations or balancing clamps. A balancing recess 242 can, for example, be a depression in the impeller 16.

[0022] According to the Fig. In the embodiment of the invention shown in Figure 1, the impeller 16 has a balancing recess 242 on its base body 30. For the unambiguous assignment of the impellers 16 to their corresponding unbalance classification 200, the impellers each have an unbalance marking 202, which is assigned to the unbalance classification 200.

[0023] The imbalance marking 202 can be, for example, an identification number or a data matrix code (DMC). The imbalance marking is preferably arranged at an easily accessible location on the impeller 16, such as the base body 30 of the impeller 16. However, it is also conceivable to arrange the imbalance marking 202 on the cover plate 32 or the bearing bush 34. The base body 30 and / or the cover plate 32 are preferably formed as a plastic injection-molded part. The data matrix code can be introduced into the plastic of the impeller 16, for example, by means of a laser and evaluated by means of camera capture.

[0024] The imbalance marking 202 can also be applied by melting the surface without adding or removing any material. Furthermore, the imbalance marking 202 can also be applied to the impeller using a printer, a stamp, or another method.

[0025] The unbalance marking 202 allows the unbalance classifications 200 of the impellers to be uniquely assigned, so that the appropriate impeller 16 can be selected as needed to compensate for the unbalance of the rotor body 18. Furthermore, an orientation marking 204 must be provided on the impeller 16, which indicates the correct orientation of the impeller 16 on the rotor body 18. The orientation marking 204 can, for example, also be the unbalance marking 202 or its arrangement on the impeller 16 itself.

[0026] The orientation marking 204 should be a visually easily perceptible feature of the impeller 16, so that the angular position to the active part can be adjusted accordingly during assembly.

[0027] In Fig. Figure 2 illustrates the process 100 for manufacturing rotors 14 for fluid pumps 10. In a first process step 110, the impellers 16 are marked with an unbalance classification 200. According to a preferred embodiment of the invention, the marking is effected by an unbalance marking 202, which is assigned to a specific unbalance classification 200. The unbalance marking 202 can, for example, be a Data Matrix code.

[0028] Subsequently, in a second process step 120, the imbalance of a rotor base body 18 is identified. The imbalance identification 120 of the rotor base body 18 can be particularly advantageously carried out in the rotor base body 18's own production line. In a subsequent process step 130, an imbalance classification 200 is determined, which reduces, and in particular substantially eliminates, the previously determined imbalance of the rotor base body 18. Based on the imbalance classification 200 identified in process step 3 130 for the targeted reduction of the imbalance of the rotor base body 18 measured here, a suitable impeller 16 is selected for the rotor base body 18 via the imbalance classification 200 and connected to the rotor base body 18 in a fourth process step 140. Preferably, the suitable impeller 16 is pressed onto the rotor base body 18.

[0029] According to an advantageous embodiment of the invention, a plurality of impellers 16 are manufactured with a predefined imbalance and provided with a corresponding imbalance classification 200, so that it is particularly easy to select and connect an impeller 16 that matches the determined imbalance of the rotor body 18. Fig. Figure 3 shows this.

[0030] According to the Fig.In the embodiment of the invention shown in Figure 3, impellers 16 of imbalance classifications one, two, and three 200a, 200b, and 200c are manufactured. The predefined imbalance classification corresponds to an impeller 16 without significant imbalance, whereby a corresponding tolerance range is conceivable. Each further predefined imbalance classification 200b, 200c exhibits a progressively increased imbalance compared to the preceding imbalance classification. After determining the imbalance of the rotor base body 18 (120), the impeller 16 of the respective suitable imbalance classification 200a, 200b, or 200c can be specifically selected and pressed onto it in the optimal angular position. In this way, suitable assemblies can be joined together particularly easily, as their imbalances mutually compensate for each other.

Claims

[1] Method (100) for producing rotors (14) for fluid pumps (10), wherein each rotor (14) has at least one rotor base body (18) and an impeller (16) connectable thereto, comprising at least the following method steps: - Marking (110) the individual impellers (16) with an unbalance classification (200), - determining (120) the unbalance of a rotor base body (18), - identifying (130) an unbalance classification (200) reducing the unbalance of the rotor base body (18), - Connecting (140) an impeller (16) with corresponding unbalance classification (200) to the rotor base body (18). [2] Method (100) according to claim 1, characterized by that a plurality of impellers (18) are produced, each with a predefined unbalance classification (200). [3] Method (100) according to one of the preceding claims, characterized bythat the impellers (16) are marked with an unbalance marking (202) which is assigned to the unbalance classification (200), in particular the predefined unbalance classification (200) [4] Method (100) according to claim 1, characterized by that at least three predefined unbalance classifications (200a, 200b, 200c) are provided, wherein the first unbalance classification (200a) corresponds to a classification of impellers (18) without significant unbalance and wherein each further unbalance classification (200b, 200c) has an increased, preferably gradually increased, unbalance compared to the previous unbalance classification (200a, 200b, 200c). [5] Method (100) according to one of the preceding claims, characterized by that the unbalance marking (202) of the impeller (16) provides information about an amount, a position, in particular an angular position and / or a direction of the predefined unbalance. [6] Method (100) according to one of the preceding claims, characterized by that the unbalance marking (202) is a data matrix code (DMC). [7] Method (100) according to one of the preceding claims, characterized by that the arrangement of the unbalance marking (202) indicates the arrangement of the unbalance on the impeller (16). [8] Method (100) according to one of the preceding claims, characterized by that the predefined unbalance classification (200) of the impellers (26) is provided by targeted arrangement of at least one balancing element (240) and / or a balancing recess (240) on the impeller (16). [9] Method (100) according to one of the preceding claims, characterized by that a plurality of balancing elements (240) and / or balancing recesses (242) are provided. [10] Method (100) according to one of the preceding claims, characterized bythat the balancing elements (240) and / or balancing recesses (240) are formed in one piece, in particular as a plastic injection-molded part connected to the impeller (16). [11] Method (100) according to one of the preceding claims, characterized by that the impellers (16) each have a base body (30), a cover plate (32) and preferably a bearing bush (34). [12] Method (100) according to one of the preceding claims, characterized by that the at least one balancing element (240) and / or the at least one balancing recess (242) is arranged on the base body (30) and / or the cover plate (23) and / or preferably the bearing bush (34).

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