Oscillating-rotor pump

Abstract

A gerotor pump (10) with an inner rotor (12) and a rotatably supported outer rotor (14), and characterized in that the outer rotor (14) is elastically supported in its axial direction and is pre-tensioned towards the inner rotor (12).

Description

Technical Field

[0001] The present invention relates to a cycloidal rotor pump according to the preamble of claim 1. Background Technology

[0002] This type of pump is described in DE 10 2019 200 560 A1 and basically has an inner rotor, an outer rotor, and a housing. Here, the outer rotor should be placed as close as possible to the flange of the housing.

[0003] However, due to unavoidable tolerances, undesirable large clearances often occur, causing problems, especially when starting the pump. Summary of the Invention

[0004] In this context, the objective of the present invention is to achieve a cycloidal rotor pump with improved starting performance.

[0005] The objective is achieved by means of a pump according to claim 1.

[0006] Therefore, the outer rotor is elastically supported in its axial direction and preloaded toward the inner rotor. In this way, the clearance described in the unavoidable tolerances can also be kept small, and the pump's starting performance is improved. Good suction performance of the pump can also be achieved, especially at high speeds and low pressures.

[0007] For details regarding the pump according to the invention and the function of its components, reference can be made to the document mentioned above, which serves as the subject of this application in that respect. Here, the outer rotor can be described as being floatably supported, and according to the invention, the axial bearing is therefore elastically configured in the axial direction.

[0008] Preferred improvements are described in the other claims.

[0009] Flexible support can be advantageously achieved between the outer rotor and the housing components, especially sleeve-shaped or canister-shaped housing components.

[0010] In a proven and advantageous manner, the outer rotor can be supported by a shaft.

[0011] In the aforementioned cases and / or when the spring element is within the housing member, however, even when sections or portions of the housing member are themselves elastically constructed, friction and / or wear between the outer rotor, particularly the shaft, and the support can be advantageously reduced when the spring element and / or shaft have an arched, in other words convex, and especially curved, preferably spherical profile at the contact point with the shaft or spring element. Ideally, this results in a very small contact surface, almost point-shaped, located near the axis of rotation of the support, particularly near the shaft of the outer rotor. This location yields a small relative velocity and an advantageous effect in terms of friction and / or wear.

[0012] Spring elements can be manufactured particularly cost-effectively as stamped and / or bent parts.

[0013] The placement of the spring element in the housing component can be achieved particularly simply and efficiently by clamping and / or inserting the spring element into the housing component.

[0014] Furthermore, in particular, besides the arched profile formed towards the outer rotor, having at least one segment extending in the axial direction provides advantages for operating and / or mounting the spring element. Specifically, this segment can be radially disposed externally.

[0015] Furthermore, the spring element may have segments of varying widths that are substantially perpendicular to the radial direction, with regions of varying widths provided in the radial direction. For example, the central region of the spring element may be configured to be relatively narrow in order to achieve the desired elastic properties, and at least one outer region may be configured to be wider in order to, for example, stabilize the spring element and its mounting.

[0016] The spring element can also be implemented as a particularly simple-to-manufacture, especially circular, and preferably metal-made disc. The disc may have one or more openings, for example, six openings distributed circumferentially, to improve elastic properties. Finally, such a disc can be inserted into a housing element particularly easily.

[0017] For the pump according to the invention, the outer rotor is preferably, in a proven manner, an electrically driven rotor.

[0018] Finally, the pump according to the invention is preferably used as an oil pump, because the advantages mentioned above can be particularly well utilized here. Attached Figure Description

[0019] Embodiments of the present invention are described in detail below with reference to the accompanying drawings. As shown herein:

[0020] Figure 1A cross-sectional view of the cycloidal rotor pump according to the present invention is shown.

[0021] Figure 2 A cross-sectional view of the spring element is shown.

[0022] Figure 3 A cross-sectional view of the shaft of the outer rotor is shown.

[0023] Figure 4 A perspective view of the outer rotor is shown.

[0024] Figure 5 A perspective view of an alternative embodiment of the spring element is shown.

[0025] Figure 6 A cross-sectional view showing an alternative embodiment of the cycloidal rotor pump according to the present invention, and

[0026] Figure 7 A top view showing an alternative embodiment of the spring element. Detailed Implementation

[0027] As in Figure 1 As can be seen in the cross-sectional view, the cycloidal rotor pump 10 according to the invention has an inner rotor 12, an outer rotor 14 supported by means of a shaft 16, and a flange member 18 and a housing member 20. The flange member 18 and the housing member 20 are sealingly connected to each other, and the outer rotor 14 is as close as possible to the flange member 18. Further details can be obtained from the documents cited above. The inner rotor 12 is rotatably supported on the housing element in the form of the flange member 18.

[0028] According to the present invention, a spring element 22 is provided between the housing member 20 and the shaft 16, the spring element, on the one hand, according to... Figure 1 The right end of the support shaft 16, and on the other hand according to Figure 1 The outer rotor 14 is preloaded to the left by the described clearance. In the illustrated case, the elastic support is achieved such that the spring element rests against the housing member 20 in the radially outer region for the fixation of the spring element, however, it protrudes toward the shaft 16 in the radially intermediate region and is spaced apart from the housing member 20 therein. In other words, the radially intermediate region of the spring element 22 bulges from a plane in which the radially outer and radially, but not axially, regions of the spring element 22 lie. Figure 5 The exact shape of the exemplary spring element 22 can be seen in the image. The housing member 20 may have a suitable profile on its inner side, such as one or more slots for receiving a section, particularly the radially outer portion of the spring element 22.

[0029] Reference Figure 2It should be noted that the central region, which contacts axis 16, can be arched, and in the case shown, particularly spherical with radius R. Thus, strictly speaking from a geometric perspective, only the outline... Figure 2 The lowest point contacts the shaft. Technically, this results in a relatively small contact position located relatively close to the axis, at which the shaft has a small relative velocity with respect to the spring element 22, thereby minimizing friction and / or wear.

[0030] As by Figure 3 As it turns out, this can be further supported by the similarly arched, and especially spherical, end profile of shaft 16. It is understood here that the described effect can still be produced even if only shaft 16 or spring element 22 has an arched profile.

[0031] exist Figure 4 In the middle, the ends of the outer rotor 14 and the shaft 16, together with the overall cylindrical structure of the outer rotor, can be seen.

[0032] Finally by Figure 5 Therefore, in the case shown, the spring element 22 has an arched profile 24 at its center, which is configured as a spherical "bump" or "recess" in the case shown, and in the case shown, according to Figure 5 Measurements show that the width of the spring element 22 is narrower in the middle region than in the two outer regions, generally from top to bottom. Specifically, the width increases towards the edges, and the transition to the widened portion is essentially sloped. In the illustrated case, the spring element has sections at both ends extending substantially in the axial direction. These sections are approximately 1 / 4 to 1 / 3 of the radial extension of the spring element 22, and... Figure 1 This can be further seen from the text.

[0033] exist Figure 6 The diagram illustrates an alternative embodiment of the cycloidal rotor pump 10 according to the invention, in which the spring element 22 is a flat disc inserted into the housing. For this purpose, the housing member 20 essentially has a shoulder 26, which can be formed over the entire circumference. However, it can also be interrupted along the circumference and, for example, can be provided with only three suitable support points for the disc serving as the spring element 22. In particular, the shaft 16, which is arched at the ends as shown, can thus ensure resilient support in a particularly simple manner.

[0034] exist Figure 7The disc used as spring element 22 is further shown in the perspective view. In the illustrated case, the disc is circular and completely flat, and has six openings 28 evenly distributed around its circumference, the diameter of which is the same for all openings 28 in the illustrated case, and corresponds to approximately one-third of the radius of the disc 22. This allows for particularly good achievement of the desired elastic properties. However, more or fewer openings and / or openings of different sizes may also be provided.

Claims

1. A cycloidal rotor pump (10) having an inner rotor (12) and an outer rotor (14) rotatably supported, characterized in that, The outer rotor (14) is elastically supported in its axial direction and preloaded toward the inner rotor (12).

2. The cycloidal rotor pump (10) according to claim 1, characterized in that, A spring element (22) is provided between the outer rotor (14) and the housing component (20) of the pump.

3. The cycloidal rotor pump (10) according to claim 1 or 2, characterized in that, The outer rotor (14) is supported by a shaft (16).

4. The cycloidal rotor pump (10) according to any one of claims 2 and 3, characterized in that, The spring element (22) and / or the shaft (16) have an arched, preferably spherical profile (24) at the contact position with the shaft or the spring element (22).

5. The cycloidal rotor pump (10) according to any one of claims 2 to 4, characterized in that, The spring element (22) is a stamped part and / or a bent part.

6. The cycloidal rotor pump (10) according to any one of claims 2 to 5, characterized in that, The spring element (22) is clamped and / or inserted into the housing member (20).

7. The cycloidal rotor pump (10) according to any one of claims 2 to 6, characterized in that, The spring element (22) has at least one segment extending in the axial direction.

8. The cycloidal rotor pump (10) according to any one of the preceding claims, characterized in that, The spring element (22) has segments with different widths in the radial direction, especially having at least one outer region that is wider than the central region.

9. The cycloidal rotor pump (10) according to any one of the preceding claims, characterized in that, The spring element (22) is a disc.

10. The cycloidal rotor pump (10) according to any one of the preceding claims, characterized in that, The outer rotor (14) is also the rotor of the electric drive device.

11. The cycloidal rotor pump (10) according to any one of the preceding claims, characterized in that, The cycloidal rotor pump is an oil pump.

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