GEARBOX WITH A HOUSING PART, A SHAFT, A FIRST COVER PART AND A SECOND COVER PART

Description

[0001] The invention relates to a transmission with a housing part, a shaft, a first cover part and a second cover part.

[0002] A device for fastening closure caps is known from DE 31 31713 A1.

[0003] A cover for closing circular openings on gearbox housings is known from DD 2 51 597 A1.

[0004] From CN 204 729 551 U an angular gear is known, whereby it is also known that a shaft in a gear is supported by means of two bearings.

[0005] From KR 10 1 933 118 B1, a leakage prevention device for a transmission with the features of the preamble of claim 1 is known as the closest prior art.

[0006] A worm gear is known from CN 202 195 000 U.

[0007] A worm gear is also known from CN 202 484 205 U.

[0008] The invention is therefore based on the object of designing a gearbox with a high degree of protection.

[0009] According to the invention, the object is achieved in the transmission according to the features specified in claim 1.

[0010] The advantage here is that the shaft bearings are not housed in the housing section located axially between the two cover sections, but rather in the cover sections themselves. Sealing rings are provided to ensure a tight connection between the cover sections and the housing section.

[0011] Since the housing components are identical to each other, they each have two seats for sealing rings, although only the other of these seats is actually used for a respective sealing ring. This keeps the number of parts required to manufacture the gearbox to a minimum.

[0012] Both bearings are each supported by the same ring area. However, only the first bearing has its first ring area supported on the radial outer side of the housing part. In the other cover part, the second ring area is supported, but not the first ring area, which accommodates the second bearing.

[0013] In this way, transverse forces and vibrations are better tolerated.

[0014] In an advantageous embodiment, the second ring region is radially spaced from the first ring region. Thus, the bearing support and seal are separable from each other.

[0015] In an advantageous embodiment, the second sealing ring is radially spaced from the first sealing ring and / or the second sealing ring is arranged at a greater radial distance than the first sealing ring,

[0016] In particular, the second ring region is arranged at a greater radial distance than the first ring region. The advantage here is that the seal on the axial side of the second bearing is provided at a much greater radial distance than on the driven side. This reliably ensures high sealing tightness, as the deflections and forces in the second ring region are kept to a minimum. The sealing function and bearing function of the second bearing are thus separable from each other. In contrast, the sealing function and bearing function of the first bearing are combined in the first ring region of the other cover part.

[0017] In an advantageous design, the ring axes of the ring areas are aligned coaxially with the shaft's axis of rotation. This is advantageous because the ring areas are aligned coaxially with the shaft, thus allowing for better support of the bearings.

[0018] In an advantageous embodiment, the area covered in the axial direction by the seat for the sealing ring formed on the second ring area is axially spaced from the area covered in the axial direction by the seat for the first sealing ring formed on the first ring area. This is advantageous in that the two ring areas are decoupled from one another, in particular with regard to deflections and vibration modes. This means that the sealing system is decoupled from the bearing system. Forces acting on the bearing are therefore kept away from the sealing system. In contrast, in the first bearing, the bearing is accommodated in the first ring area, which also serves as a seat for a sealing ring. Here, however, the first ring area is supported by the housing part, thus achieving increased stability. In contrast, the first ring area of the other cover part, which accommodates the second bearing, is not supported but is spaced from the sealing ring.

[0019] An advantageous embodiment provides that the spatial area is bounded radially inward by one cylindrical surface and radially outward by the other cylindrical surface. It is advantageous that the cylinder axis of the cylindrical surfaces is aligned parallel to the joining direction, in particular parallel to the axial direction, i.e., the direction of the shaft's axis of rotation.

[0020] In an advantageous embodiment, the seat for the second sealing ring formed on the second ring region has a cylindrical outer surface that transitions smoothly, in particular continuously and variably, into a rounded region. In particular, the seat for the second sealing ring formed on the housing part has a cylindrical outer surface that transitions smoothly, in particular continuously and variably, into a rounded region. It is advantageous that the cylinder axis of this second cylindrical outer surface is coaxial with the other cylinder axis and coaxial with the axis of rotation of the shaft.

[0021] In an advantageous embodiment, the second sealing ring is arranged in a circumferentially extending, in particular tubular, spatial region which is delimited by the two cylindrical outer surfaces and the two rounded regions, wherein the second sealing ring is pressed between the two cylindrical outer surfaces in the radial direction and is elastically expanded in the axial direction, in particular wherein the spatial region is delimited radially inwards by one cylindrical outer surface and radially outwards by the other cylindrical outer surface. It is advantageous in this case that the second sealing ring is arranged coaxially to the first sealing ring. However, the second sealing ring is radially further expanded and can therefore be arranged more securely.

[0022] In an advantageous embodiment, a gearing part, in particular a face-toothed gear, is connected to the shaft in a rotationally fixed manner, wherein the gearing part engages a pinion whose rotational axis is oriented perpendicular to the rotational axis of the gearing part. Advantageously, the gearing part, together with the meshing pinion, can be configured as a spiroplane stage or hypoid stage. This allows for high gear ratios and high torque.

[0023] In an advantageous embodiment, the first annular region of the cover part accommodating the first bearing is supported by the housing part, in particular on the radial outer side of the first annular region, wherein the second annular region of the cover part accommodating the second bearing is supported by the housing part, in particular on the radial outer side of the second annular region. The advantage here is that in the region of the first bearing, only a small deflection can be caused by forces or vibrations because the support has a stiffening effect. However, larger deflections can be caused in the second bearing, but these do not have a disruptive effect on the sealing system because the latter is arranged axially, in particular also from the second bearing, and radially spaced.

[0024] In an advantageous embodiment, the first sealing ring is arranged between the first annular region of the cover part accommodating the first bearing and the housing part, in particular on the radial outer side of the first annular region, while the second sealing ring is arranged between the second annular region of the cover part accommodating the second bearing and the housing part, in particular on the radial outer side of the second annular region. This advantageously ensures that the sealing system is undisturbed in the area of the first bearing, since the support provided by the housing part is effective there.

[0025] In an advantageous embodiment, parts are made of a metallic material, in particular steel, zinc or

[0026] Aluminum, manufactured by casting, especially die-casting. The advantage of this process is that a high level of tightness can still be achieved by compressing the sealing ring elastically.

[0027] It is particularly preferred to produce the cover part and housing part by zinc die casting.

[0028] In an advantageous embodiment, a shaft sealing ring is accommodated in the first cover part, in particular the first bearing accommodating cover part, which seals the cover part towards the shaft, wherein a closure cover is accommodated in the second cover part, in particular the second bearing accommodating cover part,

[0029] In particular, threaded holes are arranged in the first cover part for connecting a device or load that can be driven by the gearbox. Advantageously, the shaft protrudes axially, allowing a device or load to be driven. By means of the shaft seal, the first bearing can be arranged in the interior of the gearbox, which is at least partially filled with lubricating oil. This ensures good lubrication.

[0030] In an advantageous embodiment, the gearing part is arranged closer to the second bearing than to the first bearing. This is advantageous because the transverse forces introduced by the meshing gearing can be directly dissipated via the first ring area. Nevertheless, the connection between the housing part and the cover part remains sealed, since the corresponding sealing ring is radially spaced.

[0031] Further advantages arise from the subclaims.

[0032] The invention will now be explained in more detail using schematic illustrations: In the Figure 1 A cover part 1 of a gearbox is shown in cross section. In the Figure 2 A housing part 20 of the gearbox is shown in cross section. Figure 3 The housing part 20 is shown in side view. Figure 4 The gearbox is shown in cross-section. Figure 5 the gearbox is shown in side view.

[0033] As shown in the figures, the transmission has a housing part 20 in which a toothed part 47, in particular a wheel, is arranged.

[0034] The wheel 47 is connected in a rotationally fixed manner to a shaft 43, which is rotatably mounted by means of a first bearing 42 and by means of a second bearing 45.

[0035] The gear 47 is preferably face-toothed and, together with a pinion, forms an angular gear stage. The gearing is preferably hypoid gearing or spiroplan gearing. With spiroplan gearing, the pinion is an easy-to-manufacture pinion with a cylindrical envelope; with hypoid gearing, however, the pinion has a truncated cone-shaped envelope.

[0036] The first bearing 42 is accommodated in a first cover part 1 and the second bearing 45 is accommodated in a cover part 1 that is manufactured in the same way, i.e. identically, to the first cover part 1.

[0037] The cover parts 1 are connected to the housing part 20 on opposite sides of the housing part 20, as seen in the axial direction, i.e. in the direction of the axis of rotation of the shaft 43.

[0038] For this purpose, each of the two cover parts 1 has a preferably finely machined bearing seat for receiving the first bearing 42 or the second bearing 45.

[0039] The cover part 1 has an annular region 44, in particular a ring-like projection,

[0040] The bearing seat for the respective bearing (42, 45) to be accommodated is arranged on the inner wall seen in the radial direction, preferably finely machined.

[0041] A sealing seat for accommodating a seal is formed on the outer wall, as seen in the radial direction. However, this seat is preferably not machined after the production of the cover part 1, thus exhibiting a roughness caused by the casting process.

[0042] The area covered in the axial direction by this seal seat is included in the area covered in the axial direction by the bearing seat.

[0043] The cover part 1 also has a second sealing seat 4, which is arranged at a greater radial distance. This second sealing seat is also arranged in a further annular region, in particular an annular projection, in particular on its radial outer side.

[0044] The further ring region 49 is formed in the same way as the first ring region 44 in the circumferential direction.

[0045] The further annular region 49 radially surrounds the first annular region 44, but is axially less protruding than the first annular region 44. In the axial direction, the second sealing seat 4 is spaced from the first sealing seat 2.

[0046] Thus, the cover part 1 has two sealing seats (2, 4). However, the housing part 20 has only a single seat 21 for a sealing ring on its first axial side and also only a single seat 22 for a sealing ring on the other axial side.

[0047] The seat 21 is arranged at a greater radial distance than the seat 22.

[0048] Thus, the cover part 1 connected to the housing part 20 on the first axial side is tightly connected by means of sealing ring 48 at a greater radial distance than the cover part 1 connected to the housing part 20 on the other axial side is tightly connected by means of sealing ring 40.

[0049] Towards the environment, in the first cover part 1, in which the sealing ring 40 is accommodated in the seat 22, a shaft sealing ring 41 is accommodated next to the accommodated bearing 42, which seals towards the axially projecting shaft 43.

[0050] Towards the environment, in the first cover part 1, in which the sealing ring 48 is accommodated in the seat 21, a closure cover 46 is accommodated next to the accommodated bearing 45, which tightly closes the recess arranged centrally in the cover part 1.

[0051] The closure cover 46 can therefore be accommodated in the cover part 1 on the same inner diameter as the shaft sealing ring 41, whereby, depending on the respective cover part 1, only either the shaft sealing ring 41 or the closure cover 46 is accommodated.

[0052] The cover parts 1 are each connected to the housing part 20 by means of screws 50 and have threaded holes 51 to which the device to be driven can be connected and / or attached, in particular on the output side.

[0053] The sliding and screwing of the respective cover part 1 onto the housing part 20 is effected in the axial direction by mutually abutting stop surfaces of the cover part 1 and the housing part 20, in particular the two sealing rings (40, 48) which are preferably arranged at a greater radial distance.

[0054] The ring area 44 is inserted into a recess of the housing part 20 when the cover part 1 is inserted into the housing part 20.

[0055] The seat 22 arranged and formed in the recess has a cylindrical shell surface section, to which a rounded section smoothly adjoins, in particular at the end of the cylindrical shell section facing the toothed part 47.

[0056] Likewise, the annular region 44 of the cover part 1 inserted into the recess has a cylindrical shell surface section, to which a rounded section smoothly adjoins, in particular at the end of the cylindrical shell section of the cover part 1 facing away from the toothed part 47.

[0057] Thus, the sealing ring 40 is elastically deformed in a circumferentially extending tubular space such that the sealing ring 40 rests against the two cylindrical surface sections and is elastically compressed radially. In particular, the sealing ring 40 is thus wider in the axial direction than in the radial direction. The extent of the elastic expansion is defined by the stop surfaces.

[0058] The contact surfaces of the sealing ring 40, i.e., the cylindrical surface sections, extend in the axial direction. However, the axial direction also represents the insertion and connection direction of the cover part 1 with the housing part 20.

[0059] In the axial direction in front of and behind the sealing ring 40, a free air volume is still arranged, in particular to the respective two rounded sections.

[0060] The elastic pressing force acts in the radial direction on the sealing ring 40, i.e. perpendicular to the insertion direction of the cover part 1, which is inserted in the axial direction into the recess of the housing part 20.

[0061] The further sealing ring 48 arranged between the other cover part 1 and the housing part 20 is also arranged in such a tubular space area and is arranged elastically deformed between the two cylindrical shell surfaces, so that here too the radial pressing force is aligned perpendicular to the axially directed insertion direction.

[0062] Advantageously, a seal can be produced between the respective cover part 1 and the housing part 20 by means of the sealing rings (40, 48), although the cylindrical outer surfaces are unmachined after the casting of the housing part 20 and the cover parts 1.

[0063] Since the annular region 44 accommodates the bearing 45 on its radial inner side but is not supported by the housing part 20 on its radial outer side, the transverse forces introduced into the shaft 43 via the toothed part 47 can radially deflect the annular region 44, but do not influence the seal created by the sealing ring 48, since this is created by the other annular region of the same cover part 1. Therefore, the toothed part is arranged closer to the bearing 45 than to the bearing 42.

[0064] This is because the bearing 42 is accommodated in the annular region 44 of the cover part 1 located there, with this annular region 44 being supported on its radial outer side by the housing part 20. The seal arranged there is thus subject to lesser transverse deflections. The same applies to the transverse forces introduced on the output side, which, due to the support, do not cause any significant deflections in the area of the sealing ring 40, but do cause deflections of the annular region 44 on the further cover part 1 arranged on the side of the toothed part 47 facing away from the input side.

[0065] The same applies to structure-borne sound vibration modes.

[0066] In further embodiments of the invention, the sealing rings 40 and 48 are designed as O-rings. List of reference symbols

[0067] 1 Cover part 2 Seat for sealing ring, in particular O-ring 3 Contact surface 4 Second sealing seat for sealing ring, in particular O-ring 20 Housing part 21 Seat for second sealing ring 48, in particular O-ring 22 Seat for first sealing ring 40, in particular O-ring 40 First sealing ring 41 Shaft sealing ring 42 Bearing 43 Output shaft 44 Ring area, in particular ring-like projection 45 Bearing 46 Cover 47 Toothed part, in particular wheel 48 Second sealing ring 49 Second ring area, in particular ring-like projection 50 Screw 51 Threaded hole

Claims

1. A gear unit having a housing part (20), a shaft, a first cover part (1) and a second cover part (1), wherein the first cover part (1) has a first annular region (44) projecting towards the gear-unit interior, at the radial interior of which annular region there is received a first bearing (42) and at the radial exterior of which annular region there is formed a seat (2) for a sealing ring (40) which is received at this seat (2) and is arranged between the housing part (20) and the first annular region (44), wherein the second cover part (1) likewise has a first annular region (44) projecting towards the gear-unit interior, at the radial interior of which annular region there is received a second bearing (45), wherein the output shaft of the gear unit is rotatably mounted by means of the first and the second bearing, wherein the first cover part (1) has a second annular region (49) projecting towards the gear-unit interior, at the radial exterior of which annular region there is likewise formed a seat (2) for a sealing ring (48), wherein the second cover part (1) has a second annular region (49) projecting towards the gear-unit interior, at the radial exterior of which annular region there is likewise formed a seat (2) for a second sealing ring (48) which is received at this seat (2) and is arranged between the housing part (20) and the second annular region (49), wherein the rotational axis of the shaft defines the axial direction and the radial direction is defined related thereto, characterised in that the region covered in an axial direction by the first bearing (42) comprises the region covered in an axial direction by the seat (2), formed at the first annular region (44), for the first sealing ring (40), wherein the seat (2), formed at the first annular region (44), for the first sealing ring (40) has a cylindrical outer surface which merges into a rounded region in a smooth, in particular steady and differentiable, manner, wherein a seat (22), formed at the housing part (20), for the first sealing ring (40) has a cylindrical outer surface which merges into a second rounded region in a smooth, in particular steady and differentiable, manner, wherein the first sealing ring (40) is arranged in a tubular spatial region encircling in a circumferential direction, which is bounded by the two cylindrical outer surfaces and the two rounded regions, wherein the first sealing ring (40) is pressed between the two cylindrical outer surfaces in a radial direction and is elastically spread in an axial direction, the seats, formed at the cover part (1) and at the housing part (20), for the sealing rings (40, 48) are unworked.

2. A gear unit according to claim 1, characterised in that the second annular region (49) is radially at a distance from the first annular region (44).

3. A gear unit according to claim 1 or 2, characterised in that second sealing ring (48) is radially spaced apart from the first sealing ring (40) and / or in that the second sealing ring (48) is arranged at a greater radial distance than the first sealing ring (40), in particular wherein the second annular region (49) is arranged at a greater radial distance than the first annular region (44).

4. A gear unit according to any one of the preceding claims, characterised in that the ring axis of the annular regions is oriented coaxially with the rotational axis of the shaft.

5. A gear unit according to any one of the preceding claims, characterised in that the region covered in an axial direction by the seat (2), formed at the second annular region (49), for sealing ring (48) is axially at a distance from the region covered in an axial direction by the seat (2), formed at the first annular region (44), for the first sealing ring (40).

6. A gear unit according to claim 5, characterised in that the spatial region is bounded radially inwards by a cylindrical outer surface and radially outwards by the other cylindrical outer surface.

7. A gear unit according to any one of the preceding claims, characterised in that the seat (2), formed at the second annular region (49), for the second sealing ring (48) has a cylindrical outer surface which merges into a rounded region in a smooth, in particular steady and differentiable, manner, in particular wherein the seat (2), formed at the housing part (20), for the second sealing ring (48) has a cylindrical outer surface which merges into a rounded region in a smooth, in particular steady and differentiable, manner.

8. A gear unit according to claim 7, characterised in that the second sealing ring (48) is arranged in a, in particular tubular, spatial region encircling in a circumferential direction, which is bounded by the two cylindrical outer surfaces and the two rounded regions, wherein the second sealing ring (48) is pressed between the two cylindrical outer surfaces in a radial direction and is elastically spread in an axial direction, in particular wherein the spatial region is bounded radially inwards by a cylindrical outer surface and radially outwards by the other cylindrical outer surface.

9. A gear unit according to any one of the preceding claims, characterised in that a toothing part (47), in particular a toothed wheel in the form of a face gear, is connected to the shaft in a rotationally-fixed manner, wherein the toothing part (47) meshes with a pinion whose rotational axis is oriented perpendicularly to the rotational axis of the toothing part.

10. A gear unit according to any one of the preceding claims, characterised in that the first annular region (44) of the cover part receiving the first bearing (42) is supported by the housing part (20), in particular at the radial exterior of the first annular region, wherein the second annular region (49) of the cover part receiving the second bearing (45) is supported by the housing part (20), in particular at the radial exterior of the second annular region.

11. A gear unit according to any one of the preceding claims, characterised in that the first sealing ring (40) is arranged between the first annular region (44) of the cover part, receiving the first bearing (42), and the housing part (20), in particular at the radial exterior of the first annular region, wherein between the second annular region (49) of the cover part, receiving the second bearing (45), and the housing part (20) there is arranged the second sealing ring (48), in particular at the radial exterior of the second annular region.

12. A gear unit according to any one of the preceding claims, characterised in that the parts are manufactured of a metallic material, in particular steel or aluminium, by casting, in particular die casting.

13. A gear unit according to any one of the preceding claims, characterised in that a shaft sealing ring (41) is received in the first cover part (1), in particular receiving the first bearing (42), which shaft sealing ring seals the cover part (1) with respect to the shaft, wherein a sealing cover (46) is received in the second cover part (1) in particular receiving the second bearing (45), in particular wherein tapped bores (51) are arranged in the first cover part (1) for the connection of a device or load drivable by the gear unit.

14. A gear unit according to any one of the preceding claims, characterised in that the toothing part (47) is arranged closer to the second bearing (45) than to the first bearing (42).