Shaft-hub connection having a shaft with a feather key groove, a hollow shaft, and a feather key, and method for producing a shaft-hub connection

Abstract

The invention relates to a shaft-hub connection having a shaft (1) with a feather key groove, a hollow shaft (2), and a feather key (21). The hollow shaft has an inner groove, and the feather key is plugged into the feather key groove and radially protrudes into the inner groove of the hollow shaft, wherein the feather key groove is only partly filled by the feather key, and a sealing part (20) is received in the feather key groove.

Description

[0001] Shaft-hub connection, comprising a shaft with keyway, a hollow shaft and a key, and method for producing a shaft-hub connection

[0002] Description:

[0003] The invention relates to a shaft-hub connection, comprising a shaft with a keyway, a hollow shaft and a key, and a method for producing a shaft-hub connection.

[0004] It is generally known that in a shaft-hub connection, a shaft can be connected to a hollow shaft in a form-fitting manner in the circumferential direction, for example, by means of a keyway. In particular, a shaft-hub connection is known from JP H05-209 607 A as the closest prior art.

[0005] A locking pin for a clutch is known from US 2007 / 0 228 728 A1.

[0006] The invention is therefore based on the object of increasing the service life of a shaft-hub connection.

[0007] According to the invention, the object is achieved in the shaft-hub connection according to the features specified in claim 1 and in the method according to the features specified in claim 15.

[0008] Important features of the invention in the shaft-hub connection, comprising a shaft with a keyway, a hollow shaft and a key, are that the hollow shaft has an inner groove, wherein the key is inserted into the keyway and projects radially into the inner groove of the hollow shaft, wherein the keyway is only partially filled by means of the key, wherein a sealing part is received in the keyway, in particular wherein the sealing part fills the space area not filled by the key in the keyway, in particular at least partially fills it.

[0009] The advantage here is that splash water cannot penetrate into the keyway during cleaning because the sealing part seals the keyway from the environment by being arranged between the shaft and the hollow shaft. In particular, the sealing part is at least partially inserted into the keyway, in particular with a holding area, and a base area projects radially from the shaft into the inner groove of the hollow shaft, so that the sealing part seals the inner groove protruding in the axial direction towards the shaft. For this purpose, the sealing part has protruding lamellae, in particular sealing lips, on its base part, which each contact the shaft and the hollow shaft. The penetration of water into the circumferential angular area not covered by the sealing part in the circumferential direction is prevented by the shaft being pressed into the hollow shaft with a sufficiently tight fit, in particular an interference fit.Thus, there is no significant annular gap between the shaft and the hollow shaft. The sealing element closes the space created by the inner groove of the hollow shaft, which opens into the external environment. This protects the keyway from the ingress of splash water.

[0010] In an advantageous embodiment, the sealing part has a base region and a holding region, wherein the holding region is received in the keyway and / or adjacent to the key, in particular wherein the sealing part is designed with its base region and holding region as a single piece and / or in one piece. It is advantageous that the holding region inserted into the keyway holds the sealing part, and the base region assumes the sealing function with its lamellae.

[0011] In an advantageous embodiment, the base region protrudes in the axial direction beyond the area covered in the axial direction by the holding region. This has the advantage that the splash water is kept axially far enough away from the keyway. In an advantageous embodiment, lamellae are formed on the base part, in particular on the section of the base part protruding from the area covered in the axial direction by the holding region, which lamellae seal from the base part to the hollow shaft, in particular to the inner groove of the hollow shaft, and to the shaft. This has the advantage that the sealing function is arranged spatially separate from the holding function on the sealing part.

[0012] In an advantageous embodiment, the lamellae are spaced apart from one another in the axial direction, in particular at regular intervals. This is advantageous because, if one of the lamellae fails, additional lamellae are still present, thus achieving a high degree of protection against leaks.

[0013] In an advantageous design, each of the slats runs completely uninterrupted around the outer circumference of the base area. This is advantageous because the sealing function is guaranteed.

[0014] In an advantageous embodiment, the base area is concavely curved on the side facing the shaft, with the radius of curvature equal to the radius of the shaft's radial outer circumference, particularly in the area covered by the base part in the axial direction. The advantage here is that the base area and the lamellae formed on it follow the outer shape of the shaft, thus achieving improved sealing.

[0015] The slats can also be referred to as sealing lips.

[0016] In an advantageous embodiment, the holding area is semi-cylindrical. This is advantageous because the keyway is filled by the key and the sealing part.

[0017] In an advantageous embodiment, the base area is essentially cuboid-shaped. This is advantageous because the inner groove of the hollow shaft can be designed with a rectangular cross-section, thus ensuring a sufficiently good filling of the inner groove by the base area, thus ensuring tightness.

[0018] In an advantageous embodiment, the wall thickness, particularly the wall thickness measured in the axial direction, decreases monotonically, particularly strictly monotonically, with increasing distance from the base area. The advantage here is that the outermost tip of each lamina is very easily deformable, since the wall thickness is at its thinnest there. This allows for improved conformability of the lamina to the inner groove of the hollow shaft, thus ensuring a high level of tightness.

[0019] In an advantageous embodiment, a screw is screwed into a central threaded hole in the shaft, with the screw head resting against a retaining ring arranged axially in a groove of the hollow shaft or against a shaft step of the hollow shaft. The advantage here is that axial limitation can be achieved easily and cost-effectively.

[0020] In an advantageous embodiment, the inner groove of the hollow shaft is axially continuous or extends at least from one end face to the area covered by the keyway in the axial direction, in particular encompassing this area. This allows for simple manufacturing and the sealing part is not fixed in the axial direction.

[0021] In an advantageous embodiment, each lamella has the shape of a rectangular frame or ring, particularly with a trapezoidal cross-section. This advantageously follows the shape of the inner groove, thus reliably ensuring tightness. The lamellae protrude radially at each circumferential angular position.

[0022] In an advantageous embodiment, the base region, the holding region, and the lamellae are designed as a single piece and / or integrally. This is advantageous in that the sealing part can be manufactured easily and cost-effectively as an injection-molded plastic part, meaning that even a complex geometry does not increase manufacturing costs. Important features of the method for producing a shaft-hub connection are that the sealing part is separated from a plastic injection-molded part and then inserted into the keyway, in particular wherein the plastic injection-molded part comprises further sealing parts, in particular of a different size than the sealing part.

[0023] The advantage here is that different sizes of the shaft-hub connection with correspondingly different-sized sealing parts can be manufactured cost-effectively, especially for small batch sizes or even custom-made products. This is because the different-sized sealing parts can be manufactured together as a single plastic injection-molded part, from which the required sealing part can be separated as needed. These sealing parts are preferably arranged on a connecting web.

[0024] 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.

[0025] The invention will now be explained in more detail using schematic illustrations:

[0026] Figure 1 shows an oblique view of a shaft-hub connection according to the invention.

[0027] Figure 2 shows a section of the shaft-hub connection.

[0028] Figure 3 shows an exploded oblique view of the shaft-hub connection.

[0029] Figure 4 shows a sealing part 20 of the shaft-hub connection in an oblique view.

[0030] Figure 5 shows an injection-molded part 50 in an oblique view.

[0031] As shown in the figures, the shaft-hub connection comprises a shaft 1 with a keyway. A key 21 is inserted into the keyway of the shaft 1 and protrudes radially into an inner groove, in particular an axial groove, in particular a further keyway, of a hollow shaft 2 of the shaft-hub connection.

[0032] The keyway has two semi-cylindrical rounded areas, between which a cuboid-shaped area is formed.

[0033] The key 21 does not completely fill the keyway of the shaft 1 but has only one of the semi-cylindrical rounded rounding areas and the cuboid area.

[0034] Thus, one of the two semi-cylindrical rounded areas remains free even after the key 21 has been inserted.

[0035] To close this remaining space area, a sealing part 20 is inserted into this space area.

[0036] As shown in Figure 1, the sealing part 20 prevents a water jet 3 from penetrating the keyway during cleaning. The shaft 1 and the hollow shaft 2 are each made of metal, in particular steel.

[0037] The sealing part 20 is preferably made of plastic, in particular of an elastomer.

[0038] The sealing part 20 protrudes radially from the keyway of the shaft 1 into the inner groove of the hollow shaft 2 and thus seals towards the hollow shaft 2.

[0039] The sealing part has a semi-cylindrical rounded area, which fills the remaining space after the key 21 is inserted into the keyway of the shaft 1. The sealing part 20 further has a substantially cuboid-shaped area that borders the semi-cylindrical rounded area and is located radially outside the keyway of the shaft 2 and therefore protrudes into the inner groove of the hollow shaft 2.

[0040] The cuboid-shaped area of ​​the sealing part 20 projects beyond the semi-cylindrical rounded area in the axial direction and projects into the inner groove of the hollow shaft 2.

[0041] On its side facing the shaft 1, the cuboid region is concavely curved, the amount of the radius of curvature being equal to the radius of curvature of the radial outer circumference of the shaft 1 in the area covered by the cuboid region of the sealing part 20 in the axial direction.

[0042] Preferably, the inner groove extends axially completely through the hollow shaft 1 or at least from one end face of the hollow shaft 2 to and over the area covered by the keyway in the axial direction.

[0043] Lamellae 41 are formed on the cuboid-shaped region of the sealing part 20, each of which radially encircles the cuboid-shaped region of the sealing part 20. In particular, the lamellae 41 protrude radially from the transverse region of the sealing part 20 in all circumferential angular positions.

[0044] Each slat has the shape of a rectangular frame or ring.

[0045] In the axial direction, the lamellae 41 are spaced apart from one another, in particular evenly. Preferably, between two and six lamellae 41 are formed, in particular four lamellae 41 are formed. Each of the lamellae 41 has a wall thickness that decreases monotonically, in particular strictly monotonically, with increasing distance from the cuboid region of the sealing part 20, in particular a wall thickness measured in the axial direction. By means of the lamellae 41, in particular sealing lamellae, the sealing part 20 seals both with the hollow shaft 2 and with the shaft 1.

[0046] Thus, water from a water jet 3 is prevented from entering the keyway.

[0047] The axial direction is aligned parallel to the rotational axis of shaft 1. The rotational axis of the hollow shaft 2 is aligned coaxially to the rotational axis of shaft 1.

[0048] As shown in Figure 5, the sealing part 20 is made of a plastic injection-molded part 50, on which not only the sealing part 20 but also corresponding sealing parts of different sizes are molded together.

[0049] Thus, the sealing part 20 and the other sealing parts are encompassed by the plastic injection-molded part, in particular being formed integrally, i.e., as a single piece, on the plastic injection-molded part. The sealing parts are provided on the plastic injection-molded part 50 at a thinned predetermined breaking point that can be easily separated.

[0050] The material of the sealing part 20 is preferably an elastomer, in particular rubber.

[0051] In further embodiments according to the invention, the key is designed without semi-cylindrical rounded areas, in particular so that the key is designed as a cuboid-shaped body.

[0052] List of reference symbols

[0053] 1 shaft 2 hollow shaft

[0054] 3 water jet

[0055] 20 Sealing part

[0056] 21 key

[0057] 22 Screw 40 semi-cylindrical section

[0058] 41 slats

[0059] 42nd level

[0060] 50 injection-molded parts

Claims

Patent claims:

1. Shaft-hub connection, comprising a shaft with a keyway, a hollow shaft and a key, the hollow shaft having an inner groove, the key being inserted into the keyway and projecting radially into the inner groove of the hollow shaft, characterized in that the keyway is only partially filled by means of the key, a sealing part being received in the keyway, in particular the sealing part filling, in particular at least partially filling, the space area not filled by the key in the keyway.

2. Shaft-hub connection according to claim 1, characterized in that the sealing part has a base region and a holding region, wherein the holding region is received in the keyway and / or adjoins the key, in particular wherein the sealing part with its base region and holding region is designed in one piece and / or in one part.

3. Shaft-hub connection according to one of the preceding claims, characterized in that the base region projects in the axial direction beyond the region covered by the holding region in the axial direction.

4. Shaft-hub connection according to one of the preceding claims, characterized in that the base part, in particular on the section of the base part projecting from the area covered by the holding area in the axial direction, is formed with lamellae which seal from the base part to the hollow shaft, in particular to the inner groove of the hollow shaft, and to the shaft.

5. Shaft-hub connection according to one of the preceding claims, characterized in that the lamellae are spaced apart from one another in the axial direction, in particular are regularly spaced apart from one another.

6. Shaft-hub connection according to one of the preceding claims, characterized in that each of the lamellae runs completely uninterrupted around the outer circumference of the base region.

7. Shaft-hub connection according to one of the preceding claims, characterized in that the base region is designed to be concavely curved on its side facing the shaft, the radius of curvature being equal to the radius of the radial outer circumference of the shaft, in particular in the region covered by the base part in the axial direction.

8. Shaft-hub connection according to one of the preceding claims, characterized in that the holding area is semi-cylindrical.

9. Shaft-hub connection according to one of the preceding claims, characterized in that the base region is cuboid-shaped, in particular substantially cuboid-shaped.

10. Shaft-hub connection according to one of the preceding claims, characterized in that the wall thickness, in particular the wall thickness measured in the axial direction, decreases monotonically, in particular strictly monotonically, with increasing distance from the base region.

11. Shaft-hub connection according to one of the preceding claims, characterized in that a screw is screwed into a central threaded bore of the shaft, the screw head of the screw resting on a locking ring arranged in an axially form-fitting manner in an annular groove of the hollow shaft or on a shaft step of the hollow shaft.

12. Shaft-hub connection according to one of the preceding claims, characterized in that the inner groove of the hollow shaft is axially continuous or extends at least from one end face to the area covered by the keyway in the axial direction, in particular and encompasses this area.

13. Shaft-hub connection according to one of the preceding claims, characterized in that each lamella has the shape of a rectangular frame or ring, in particular with a trapezoidal cross-section.

14. Shaft-hub connection according to one of the preceding claims, characterized in that the base region, the holding region and the lamellae are designed in one piece and / or in one part.

15. A method for producing a shaft-hub connection according to one of the preceding claims, characterized in that the sealing part is separated from a plastic injection-molded part and is then inserted into the keyway, in particular wherein the plastic injection-molded part comprises further sealing parts, in particular of a different size to the size of the sealing part.

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