System and method for determining an inclination angle of a shaft seal

Abstract

System comprising bearings, a shaft seal and a housing part as well as a testing device for checking the installation position of the shaft seal and a shaft, in particular the rotor shaft of an electric motor of the system, wherein the shaft is rotatably mounted relative to the housing part by means of the bearings, in particular wherein the bearings are accommodated in the housing part, wherein the shaft sealing ring is accommodated in the housing part and seals against the shaft, in particular wherein a sealing lip of the shaft sealing ring seals against the shaft, wherein the testing device comprises a tube, the opening of which is axially remote from the shaft sealing ring and is covered with a transparent disc which has a first marking, in particular a first crosshair, wherein the shaft sealing ring has an annular groove which is continuously circumferential, in particular in the circumferential direction, into which the pipe is inserted, wherein an axial end portion of the shaft protrudes into the tube.

Description

[0001] The invention relates to a system and a method for determining an inclination angle of a shaft sealing ring.

[0002] It is generally known that a shaft seal is intended to seal a rotatably mounted shaft.

[0003] From DE 2 255 448 A, the closest prior art is known a device for making the inner profile of rotating bodies visible.

[0004] From DE 1 807 710 A a device for testing in particular the sealing edge distance of radial shaft seals is known.

[0005] A positioning of a radial shaft seal is known from DE 10 2014 209 122 A1.

[0006] The invention is therefore based on the object of ensuring the service life of the shaft seal.

[0007] According to the invention, the object is achieved by the system according to the features specified in claim 1 and by the method according to the features specified in claim 15.

[0008] Important features of the invention in the system are that the system comprises bearings, a shaft seal and a housing part as well as a testing device for checking the installation position of the shaft seal and a shaft, in particular the rotor shaft of an electric motor of the system, wherein the shaft is rotatably mounted relative to the housing part by means of the bearings, in particular wherein the bearings are accommodated in the housing part, wherein the shaft sealing ring is accommodated in the housing part and seals against the shaft, in particular wherein a sealing lip of the shaft sealing ring seals against the shaft, wherein the testing device comprises a tube, the opening of which is axially remote from the shaft sealing ring and is covered with a transparent disc which has a first marking, in particular a first crosshair, wherein the shaft sealing ring has an annular groove which is continuously circumferential, in particular in the circumferential direction, into which the pipe is inserted, wherein an axial end portion of the shaft protrudes into the tube.

[0009] The advantage of this approach is that it allows for simple verification of the correct installation of the shaft seal. Simply insert a tube into the annular groove of the shaft seal and then align the viewing direction with the intersection points of the crosshairs. This allows for a deviation of the radial center of the shaft face to be identified if it exceeds a permissible value. This allows for the detection of tilted installation of the shaft seal, allowing for repairs to be initiated.

[0010] In an advantageous embodiment, the first marking is arranged on the side of the disk facing away from the shaft seal, in particular the upper side. The advantage here is that the first marking is clearly visible.

[0011] In an advantageous embodiment, the marking, in particular a crosshair intersection point, is arranged centrally on the disc, in particular a circular disc. Advantageously, the disc can be designed as a circular disc and is inserted into a circular receiving opening in the tube, so that the circular disc is precisely aligned with the tube, i.e., the rotational symmetry axis of the circular disc is aligned coaxially with the rotational symmetry axis of the tube.

[0012] In an advantageous embodiment, a visually recognizable marking, in particular a centering hole, is arranged centrally on the end face of the shaft, in particular on the shaft's rotational axis. This is advantageous in that the radial center can be identified and / or is easily recognizable by the center point of the marking, in particular the centering hole. Thus, a deviation, in particular a spacing, between the intersection point of the crosshairs in the viewing direction and the center point of the end face of the shaft, i.e., the center point of the marking, is easily recognizable.

[0013] In an advantageous embodiment, the tube rests with its end face facing the shaft seal, particularly directly and flatly, against the bottom of the annular groove. This flat contact advantageously aligns the rotational symmetry axis of the tube coaxially with the annular axis of the shaft seal.

[0014] In an advantageous embodiment, the tube is designed as a hollow cylinder or has an inner opening stepped in the axial direction, in particular a stepped bore, In particular, the inner diameter of the tube increases monotonically with decreasing distance from the shaft seal. The advantage here is that rotor shafts of different thicknesses can protrude into the tube, although they may only protrude axially to different depths. This allows the tube to be used for various rotor shaft sizes.

[0015] In an advantageous embodiment, the outer circumference of the tube is the outer circumference of a vertical circular cylinder. It is advantageous that the rotational symmetry axis of the tube is aligned parallel to the ring axis of the shaft seal.

[0016] In an advantageous embodiment, a shaft end face, particularly an axial one, is arranged as the shaft surface area closest to the disk. This is advantageous because the shaft can be positioned as close as possible to the disk and, as the shaft end, has a clearly visible radial center. Thus, any deviation caused by the inclination of the shaft seal can be reliably and clearly detected.

[0017] In an advantageous embodiment, the radial center of the shaft, in particular the axial end face, has a particularly visually recognizable marking. This is advantageous because any distance or deviation between the radial center and the rotational symmetry axis of the tube is easily recognizable.

[0018] In an advantageous embodiment, the marking is a centering hole, in particular designed as a blind hole, In particular, the centering hole is located centrally in the end face of the shaft. The advantage here is that the marking can be produced easily and cost-effectively with high precision.

[0019] In an advantageous embodiment, a first crosshair is attached to the disc, particularly on the side of the disc facing away from the shaft seal. This provides the advantage of a simple and cost-effective solution.

[0020] In an advantageous embodiment, a second crosshair is attached to the disc, particularly on the side of the disc facing the shaft seal. Advantageously, the straight line connecting the two intersection points of the crosshairs is aligned coaxially with the rotational symmetry axis of the tube and / or the ring axis of the shaft seal.

[0021] In an advantageous embodiment, the tube has a rotational symmetry axis which is aligned with the ring axis of the shaft seal, In particular, the inclination of the shaft seal's ring axis to the connecting line of the intersection points of the two crosshairs can be optically determined by determining the deviation of the radial center of the shaft's end face from the connecting line of the two intersection points. The advantage here is that the tube is precisely aligned with the shaft seal, thus making any deviation of the radial center of the shaft from the tube's rotational symmetry axis easily and clearly detectable.

[0022] In an advantageous embodiment, the intersection points of the two crosshairs are arranged on the rotational symmetry axis of the tube. This is advantageous because any deviation, i.e., any spacing, of the radial center of the shaft, in particular the center of the shaft's end face, from the straight line connecting the two crosshair intersection points can be quickly and easily detected.

[0023] In an advantageous embodiment, the outer circumference of the tube is designed as a cylinder, in particular as the outer surface of a cylinder, which has two diametrically opposed flattened portions on one of its end faces. This is advantageous in that a high torque can be applied to the tube using a tool.

[0024] In an advantageous embodiment, the centering hole has a conical section. This is advantageous because the center of the centering hole is clearly visible as the radial center of the shaft.

[0025] Important features in the method for determining an inclination angle of a shaft seal of a system are that the inclination angle between the ring axis of the shaft seal and the axis of rotation of the shaft by detecting and / or determining a deviation or a distance of the radial center of the end face of the shaft and / or the marking arranged on the end face of the shaft from the connecting line of the intersection points of the two crosshairs.

[0026] The advantage here is that the observer can adjust their viewing direction so that the two cross-sectional points are arranged exactly one behind the other in the viewing direction, i.e. on a common straight line. This makes it possible to detect any deviation of the radial center from this line. In particular, it can be determined whether a permissible degree of deviation has been exceeded and whether the annular axis of the shaft seal has an unacceptably large angle of inclination to the line or to the viewing direction. The alignment of the tube to the shaft seal can be carried out very precisely because the tube rests flatly on the groove base of the continuously circumferential annular groove of the shaft seal. The annular axis of the annular groove is aligned coaxially with the annular axis of the shaft seal. The disc is designed as a circular disc, with its continuous axis of rotational symmetry also being aligned coaxially with the annular axis of the shaft seal.This makes it possible to determine the angle of inclination very easily, quickly and precisely.

[0027] Further advantages emerge from the dependent claims. The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the problem and / or the problem posed by comparison with the prior art.

[0028] The invention will now be explained in more detail using schematic illustrations: In the Fig. 1 shows a cross-section of a test device for checking the installation position of a shaft seal. In the Fig. 2 shows a transparent oblique view of the test fixture. In the Fig. 3 shows a top view of the test device. In the Fig. Figure 4 shows a cross-section through the testing device used in a storage arrangement.

[0029] As shown in the figures, the test device comprises a tube 1 whose first opening, in particular the opening axially facing away from a shaft seal 42, is covered by a transparent disc 2. The disc is preferably made of plastic or glass.

[0030] In particular, a crosshair 20 is arranged on the upper side of the disc 2 and another crosshair is arranged on the underside of the disc 2.

[0031] Preferably, the tube 1 has a stepped bore on its inside, which has at least one step 3.

[0032] The bearing assembly includes a bearing plate 41 associated with the housing of an electric motor, which accommodates the shaft seal 42, which seals against a rotor shaft 43. A sealing lip of the shaft seal 42 contacts the rotor shaft 43.

[0033] The rotor shaft 43 is rotatably mounted, with a first bearing for rotatably supporting the rotor shaft 43 being housed in the bearing plate 41, and a second bearing for rotatably supporting the rotor shaft 43 being housed in a bearing flange of the electric motor housing. The bearing flange is connected to a stator housing, which is connected to the stator housing on its side facing away from the bearing flange in the axial direction.

[0034] The axial direction is aligned parallel to the rotational axis of the rotor shaft 43. The radial direction is related to the rotational axis of the rotor shaft, and the circumferential direction is also related to the rotational axis of the rotor shaft.

[0035] The ring axis of the shaft seal should ideally be aligned coaxially with the rotational axis of the rotor shaft 43. However, deviations may also occur due to manufacturing processes, which result in a non-zero angle of inclination.

[0036] To determine whether this angle of inclination exceeds a permissible value, the tube 1 is inserted with its circular ring-shaped bottom surface into the annular groove 40 of the shaft seal 42. Preferably, the annular groove 40 has a U-shaped cross-section into which the tube 1 can be inserted.

[0037] Advantageously, the end face 4 of the tube 1 facing the shaft sealing ring 42 lies flat against the groove bottom of the annular groove 40 of the shaft sealing ring 42.

[0038] The rotor shaft 43 projects into the tube 1.

[0039] The end face of the rotor shaft 43 facing the disk 2 is visible through the disk 2. This end face has a circular radial outer edge and a centering hole that indicates the radially central position on the end face of the rotor shaft 43.

[0040] If an observer looks at the disk 2 in the direction of the rotational axis of the rotor shaft 43, the intersection point of the crosshairs 20 mounted on the top side, i.e., the front side facing the observer, is located exactly in front of the radially centered position of the end face of the rotor shaft 43 if the shaft seal is correctly aligned. This is the case if the ring axis of the shaft seal 42 is aligned coaxially with the rotational axis of the rotor shaft 43.

[0041] The crosshair 20 attached to the disc therefore appears to be aligned with the center of the front side of the rotor shaft 43.

[0042] In order for the observer to be able to align his viewing direction as accurately as possible, the disc 2 also has the further crosshair on its underside, i.e. the rear side as seen from the observer, of the disc 2, so that the observer can align the two crosshairs 20 by moving his own position relative to the disc 2.

[0043] After this alignment, i.e. flush relative alignment of the observer, to the disk 2, the observer is able to recognize deviations of the radially central position of the end face and thus detect an incorrect positioning of the shaft sealing ring 42.

[0044] The shaft seal 42 is designed as a rotating body. In particular, the shaft seal exhibits continuous rotational symmetry with respect to its axis of rotational symmetry, which is only inclined by the angle of inclination relative to the axis of rotation of the rotor shaft. The ring axis of the annular groove is thus aligned coaxially with the axis of rotational symmetry of the shaft seal 42.

[0045] The outer circumference of the tube 1 is designed as a cylinder, in particular as a lateral surface of a cylinder, wherein one of the end faces of the cylinder has two diametrically opposed flattened portions 30.

[0046] The flats 30 allow for easy rotation of the tube 1 by applying a tool to the flats 30. This facilitates and simplifies insertion into the annular groove by additionally rotating the tube 1 during insertion. In particular, this ensures that the tube 1 rests flat against the bottom of the annular groove of the shaft seal 42.

[0047] In particular, the U-shaped cross section of the annular groove 40 enables the pipe 1 to lie flat against the shaft sealing ring 42. Not only does the annular surface of the end face of the pipe 1 facing the shaft sealing ring 42 lie directly and flat against the groove bottom of the annular groove 40 of the shaft sealing ring 42, but the radially inner and outer lateral surfaces of the hollow-cylindrical pipe 1 also lie directly and flat against the groove bottom of the annular groove 40 of the shaft sealing ring 42.

[0048] Disc 2 is made of a transparent material.

[0049] The stepped bore enables the use of tube 1 with rotor shafts of different diameters. For example, a rotor shaft that is thin in its axial end region, i.e., a rotor shaft with a first outer diameter in its axial end region, extends to the front of disk 2, and a second rotor shaft, which has a second outer diameter in its axial end region, extends to the first step of the stepped bore, wherein the second outer diameter is larger than the first outer diameter and / or larger than the smallest clear inner diameter, i.e., the first inner diameter, at the first step of tube 1.

[0050] A further stage, whose smallest clear inner diameter is larger than the first clear inner diameter, makes it possible to allow a rotor shaft 43 to protrude into the tube 1, which has a larger outer diameter in its axial end region than the smallest inner diameter of the further stage.

[0051] In further embodiments according to the invention, the tube 1 is not designed with a stepped bore, but only with a bore which has a single bore diameter.

[0052] In further embodiments according to the invention, at least one lens is arranged at a stage 3. Thus, even a front side of the rotor shaft far away from the disk 2 can be visually magnified, and therefore also the deviation of the radial center from the intersection points of the crosshairs 20. List of reference symbols 1 pipe 2 panes, transparent 3rd level 4 End face, especially annular surface 20 Crosshair 30 Flattening 40 annular groove with U-shaped cross-section 41 Bearing shield 42 Shaft seal 43 Rotor shaft QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 2 255 448 A

[0003] DE 1 807 710 A

[0004] DE 10 2014 209 122 A1

[0005]

Claims

[1] System comprising bearings, a shaft sealing ring (42) and a housing part as well as a testing device for checking the installation position of the shaft sealing ring (42) and a shaft, in particular a rotor shaft (43) of an electric motor of the system, wherein the shaft is rotatably mounted relative to the housing part by means of the bearings, in particular wherein the bearings are accommodated in the housing part, wherein the shaft sealing ring (42) is accommodated in the housing part and seals off the shaft, in particular wherein a sealing lip of the shaft sealing ring (42) seals off the shaft, characterized by , that the testing device comprises a tube (1) whose opening axially remote from the shaft sealing ring (42) is covered with a transparent disc (2) which has a first marking, in particular a first crosshair (20), wherein the shaft sealing ring (42) has an annular groove (40) which runs continuously in particular in the circumferential direction and into which the pipe (1) is inserted, wherein an axial end region of the shaft projects into the tube (1). [2] System according to claim 1, characterized by that the first marking is arranged on the side of the disc (2) facing away from the shaft sealing ring (42), in particular the upper side. [3] System according to one of the preceding claims, characterized by , that the marking, in particular a crossing point of the crosshairs, is arranged centrally on the disc (2), in particular a circular disc, and / or that a visually recognizable marking, in particular a centering hole, is arranged centrally on the end face of the shaft, in particular on the axis of rotation of the shaft. [4] System according to one of the preceding claims, characterized bythat the tube (1) rests with its end face (4) facing the shaft sealing ring (42), in particular directly and flatly, on the groove bottom of the annular groove (40). [5] System according to one of the preceding claims, characterized by , that the tube (1) is hollow-cylindrical or has an inner opening stepped in the axial direction, in particular a stepped bore, In particular, the clear inner diameter of the pipe (1) increases monotonically with decreasing distance from the shaft sealing ring (42), and / or that the outer circumference of the tube (1) is the outer circumference of a vertical circular cylinder. [6] System according to one of the preceding claims, characterized by that one, in particular axial, end face of the shaft is arranged as the surface area of ​​the shaft that is closest to the disc (2). [7] System according to one of the preceding claims, characterized bythat the radial center of the, in particular axial, end face of the shaft has a particularly visually recognizable marking. [8] System according to one of the preceding claims, characterized by that the marking is a centering hole, in particular designed as a blind hole, in particular wherein the centering hole is located centrally in the end face of the shaft. [9] System according to one of the preceding claims, characterized by that a first crosshair (20) is attached to the disc (2), in particular to the side of the disc (2) facing away from the shaft sealing ring (42). [10] System according to one of the preceding claims, characterized by that a second crosshair (20) is attached to the disc (2), in particular to the side of the disc (2) facing the shaft sealing ring (42). [11] System according to one of the preceding claims, characterized by , that the tube (1) has a rotational symmetry axis which is aligned with a ring axis of the shaft sealing ring (42), in particular wherein the inclination of the ring axis of the shaft sealing ring (42) to the connecting line of the intersection points of the two cross hairs (20) can be determined optically by determining the deviation of the radial center of the end face of the shaft from the connecting line of the two intersection points. [12] System according to one of claims 10 or 11, characterized by that the intersection points of the two crosshairs (20) are arranged on the rotational symmetry axis of the tube (1). [13] System according to one of the preceding claims, characterized by that the outer circumference of the tube (1) is designed as a cylinder, in particular as the outer surface of a cylinder, which has two diametrically opposed flattened portions (30) on one of its end faces (4). [14] System according to one of claims 8 to 13, characterized bythat the centering hole has a conical area. [15] Method for determining an inclination angle of a shaft sealing ring (42) of a system according to one of the preceding claims, characterized by , that the angle of inclination between the ring axis of the shaft seal (42) and the axis of rotation of the shaft by detecting and / or determining a deviation or a distance of the radial center of the end face of the shaft and / or the marking arranged on the end face of the shaft from the connecting line of the intersection points of the two crosshairs (20).

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