Gearbox with housing and bearing for rotating a shaft

Description

[0001] The invention relates to a gearbox with a housing part and bearing for the rotatable mounting of a shaft.

[0002] It is generally known that a gearbox is equipped with a housing part and bearings for the rotatable mounting of a shaft.

[0003] A gearbox is known from EP 3 798 076 A1.

[0004] A gearbox is known from DE 39 28 739 A1.

[0005] A sealing arrangement is known from CN 1 040 749 55 A.

[0006] A gearbox is known from CN 1 06 555 868 A.

[0007] From the US 3 383 937 A The closest state of the art is a lubrication arrangement for a gearbox with bearings.

[0008] From the CN 103 867 691 A A lubrication arrangement for a bearing arrangement is known.

[0009] From the DE 10 2007 020453 A1 A gearbox with a lubrication circulation system is known.

[0010] From the DE 39 28 739 A1 A gearbox is known.

[0011] The invention is therefore based on the objective of further developing a gearbox to be oil-tight, thereby reducing losses.

[0012] According to the invention, the problem is solved in the transmission according to the features specified in claim 1.

[0013] An advantage of this design is that oil tightness can be achieved despite the use of a non-contact seal. Even when the oil inside the gearbox is heavily agitated during operation and the entire interior is saturated with oil, leakage towards the non-contact seal can still be prevented.

[0014] Oil is supplied to the bearing via the first free chamber. This first free chamber is separated from the non-contact seal by a barrier adjacent to it, which the oil can only overcome with difficulty. A second free chamber then follows this barrier, carrying away any oil that has overcome the barrier via a discharge channel. This channel allows the oil to flow into the calmed oil sump through a pipe section. The pipe section opens downwards into the oil sump to prevent backflow or backup. This keeps the second free chamber protected from backflowing oil and thus protects the non-contact seal.

[0015] The use of a non-contact seal reduces frictional power, and therefore also the power loss of the gearbox, especially compared to a shaft seal.

[0016] According to the inventionThe bearing cap of the gearbox has a centering collar that projects into and / or is inserted into a bearing mounting bore in the housing part that receives the outer ring of the bearing and passes through the housing part. wherein the first clearance is formed by a radial spacing of the centering collar from the shaft, in particular wherein the centering collar is a hollow cylindrical area of ​​the bearing cap projecting axially from the bearing cap. An advantage of this is that a narrow centering collar results in a large first clearance, thus ensuring good oil supply to the bearing.

[0017] According to the inventionThe annular gap has a smaller radial width than the first and second free spaces, in particular where the annular gap has a radial width of less than 3 millimeters, and in particular less than 1 millimeter. It is advantageous that the barrier is formed by the annular gap, which is created by the only slightly larger clear inner diameter of the recess in the disc. Thus, the disc creates a barrier and can simultaneously function as a labyrinth disc for the non-contact seal.

[0018] According to the invention A feed channel is formed in the housing part, which The oil either flows directly into the first free space, or via a third cavity formed between the bearing cap and the housing part, into the first free space. Lubricating oil can be supplied to the supply channel from an intermediate reservoir, and oil splashed up into the intermediate reservoir and collected by a collection device is fed to the intermediate reservoir via a feeder. An advantage of this design is that the bearings can be well supplied with lubricating oil.

[0019] According to the invention The pipe section is an angled pipe and / or it terminates in the gearbox's oil sump. It is advantageous for the pipe section to terminate as deep as possible in the oil sump, thus preventing backflow caused by rapidly moving oil. This would compromise the non-contact seal.

[0020] According to the inventionThe opening of the end of the pipe section furthest from the axial bore is open downwards; in particular, the circular opening of the end of the pipe section furthest from the axial bore is oriented such that the normal vector of the plane containing the circular opening is parallel to the direction of gravity. An advantage of this is that backflow is reduced because horizontally flowing currents in the oil sump cannot build up significant pressure that could then cause oil to flow back from the oil sump into the pipe section.

[0021] In an advantageous embodiment, the gearbox is arranged in an industrial plant such that the axis of rotation of the shaft is horizontally oriented and / or the bearing is located above the oil level of the lubricating oil when the gearbox is stopped. It is advantageous that the gearbox can, for example, be placed on the floor of the plant or installed in a machine in such a way that the axis of rotation of the shaft is horizontally oriented.

[0022] In an advantageous embodiment, the inner ring of the bearing is mounted on the shaft, wherein the outer ring of the bearing is axially limited by a retaining ring recessed in an annular groove of the housing part, the first clearance being axially adjacent on one side to the retaining ring and on the other side to the washer. It is advantageous that the first clearance is axially fixed by the retaining ring.

[0023] In an advantageous embodiment, the first free space is bordered by the retaining ring, the washer, the shaft, the bearing, and the housing part. An advantage of this is that oil can be supplied to the rolling elements of the bearing from the first free space.

[0024] According to the invention The annular gap opens axially into the second free space and counter-axially into the first free space. An advantage of this is that the annular gap forms an obstacle or barrier for the oil.

[0025] In an advantageous embodiment, the disc, together with another disc mounted on the shaft and non-rotatably connected to the shaft, in particular another labyrinth disc, forms the non-contact seal. It is advantageous that the non-contact seal can be designed as a labyrinth seal.

[0026] In an advantageous embodiment, the first free space is annular, with the annular axis of the first free space being aligned coaxially with the axis of rotation of the shaft and / or the axis of rotation of the bearing. An advantage of this is that the lubrication of the bearing can be carried out uniformly in the circumferential direction.

[0027] In an advantageous embodiment, the second free space is annular, with the annular axis of the second free space being aligned coaxially with the axis of rotation of the shaft and / or the axis of rotation of the bearing. This is advantageous because the non-contact seal can be uniformly protected in the circumferential direction, and any oil splashed off the shaft can be collected in the second free space.

[0028] In a preferred embodiment, the drain channel is formed between the bearing cover and the housing part. The advantage here is that no additional part is required.

[0029] In a preferred design, the drain channel is vertically oriented. This has the advantage of allowing the oil to drain quickly.

[0030] In a preferred design, the axial bore is horizontally oriented. An advantage of this design is its ease of manufacture.

[0031] In an advantageous embodiment, the axial bore is positioned above the oil level established when the gearbox is at rest. An advantage of this design is that the non-contact seal is automatically protected in the resting state. This is because the bearing is located above the axial bore and therefore further away from the oil than the axial bore. In the axial direction, the housing component has no further through-hole located below the axial bore or between the bearing mounting bore and the axial bore. Thus, the seal is protected from oil.

[0032] In an advantageous embodiment, during operation of the gearbox, the portion of the pipe section not inserted into the axial bore is supplied with oil, particularly by the movement of the oil caused by a gear of the gearbox. An advantage of this is that, even if the oil sump is agitated, the portion of the pipe section is supplied with oil, but the pipe section prevents backflow of oil.

[0033] Further advantages arise from the dependent claims. The invention is not limited to the combination of features of the claims. For those skilled in the art, further meaningful combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent, in particular from the problem statement and / or the problem arising from a comparison with the prior art.

[0034] The invention will now be explained in more detail with reference to schematic illustrations: In the Figure 1A section of a cutaway transmission according to the invention is schematically sketched.

[0035] In the Figure 2 A corresponding oblique view is shown.

[0036] As shown in the figures, the lubricating oil of the gearbox is to be kept away from a non-contact seal, which is exemplified as a labyrinth seal 5.

[0037] For this purpose, a bearing 8, in particular a rolling bearing, is included in a housing part 3 for supporting a shaft 1, which has a toothed area which engages with a gear 2 which is non-rotatably connected to an intermediate shaft of the gearbox, which is also rotatably mounted.

[0038] To lubricate the bearing 8, lubricating oil is supplied above the bearing 8 via a supply channel into a first circumferential free space 4, from which the bearing 8 can be supplied with lubricating oil.

[0039] The supply to the feed channel is enabled either actively as pressure lubrication by an oil pump or passively by collecting upwardly sprayed oil, in particular that which is collected in an intermediate storage tank from which the feed channel is supplied.

[0040] The lubricating oil that is not discharged via bearing 8 collects at the lowest point of the circumferential free space 4.

[0041] To prevent this oil from penetrating axially towards the non-contact seal, in particular towards the labyrinth seal 5, an oil barrier is formed by a disk 13, in particular a labyrinth disk, which is mounted on the shaft 1, by having the smallest possible annular gap between the shaft 1 and the inner contour 6 of the disk 13, and the inner contour 13 thus forms a barrier for the oil.

[0042] Only when the oil level at the lowest point has risen sufficiently can the barrier be overcome by the oil.

[0043] The disk 13 is shaped such that a second circumferential free space 7 is formed on the side of the barrier facing away from the bearing 4, in particular on the side of the annular gap facing away from the bearing 4, so that the oil which has overcome the annular gap in the axial direction is flung off the rotating shaft 1 into the second free space 7. A drain channel 11 is formed at the lowest point of this second free space 7, so that the oil cannot accumulate there.

[0044] This drain channel 11 opens into an axial bore in the housing part 3, into which a pipe section 10, designed as an angled pipe, is inserted. The pipe section 10 extends as deep as possible into the oil sump.

[0045] The oil level of the oil sump is lower than the lowest point of bearing 8 when the gearbox is at rest, in particular when it is stationary.

[0046] However, when the gearbox is in operation, the lubricating oil is turbulently agitated, so that the oil covers or splashes the pipe section 10 up to its highest point, in particular its surface point. Thus, the pipe section 10 prevents backflow of oil into the axial bore and the drain channel 11, thereby protecting the non-contact seal from the oil.

[0047] The bearing cover 9 separates the oil-carrying area and thus protects against the ingress of dirt.

[0048] In particular, the gearbox is part of an industrial plant or machine, wherein the gearbox is arranged in the plant such that the bearing 8 is arranged in the direction of gravity above the oil sump, particularly in the rest state of the gearbox.

[0049] The first free space 4 is formed by inserting the bearing cap 9 with a centering collar into the bearing receptacle, in particular into the bearing receptacle bore, wherein the centering collar of the bearing cap 9 is radially spaced from the shaft 1 and thus the first free space 4 is formed.

[0050] In further embodiments according to the invention, the shaft 1 is connected to another gear in a rotationally fixed manner instead of the toothed area. Reference symbol list

[0051] 1 Shaft 2 Gear 3 Housing part 4 First free space, in particular circumferential free space 5 Labyrinth seal with further disc, in particular labyrinth disc 6 Inner contour of the disc 13, in particular for forming a barrier 7 Second free space, in particular circumferential free space 8 Bearing 9 Bearing cover 10 Pipe part, in particular angled pipe 11 Drain channel 12 Oil sump 13 Disc, in particular labyrinth disc

Claims

1. A gear unit with housing part (3), shaft (1) and bearing (8) for rotatably mounting the shaft (1), wherein the bearing (8) is received in the housing part (3), wherein lubricating oil can be supplied to the rolling elements of the bearing from a first free space (4), wherein a non-contact seal for sealing off the bearing acted upon by lubricating oil towards the surroundings is arranged on that side of the first free space (4) remote from the bearing (8) in the axial direction, wherein a disc (13) is connected to the housing part (3), wherein the shaft (1) protrudes through a cutout in the disc (13), wherein an annular gap is formed between the shaft (1) and the disc (13), wherein a second free space (7) is arranged on that side of the disc (13) which is remote from the first free space (4) in the axial direction, wherein [at the] deepest point in the direction of gravity of the second free space (7) a discharge duct opens into the second free space (7) for discharging lubricating oil from the second free space (7) into the discharge duct, wherein an axial bore in the housing part (3) opens into the discharge duct and is connected at its end region remote from the discharge duct to a tube part (10), characterised in that the tube part (10) is an angled tube and / or the tube part (10) opens into the oil sump (12) of the gear unit, the mouth opening of that end of the tube part (10) which is remote from the axial bore is opened downwards, i.e. in the direction of gravity downwards, with a bearing cover (9) of the gear unit having a centring collar which protrudes and / or is inserted into a bearing receptacle bore, which receives the outer ring of the bearing and passes through the housing part (3), of the housing part (3), with the first free space (4) being formed by a radial spacing of the centring collar from the shaft (1), with the annular gap being of a lesser radial width than the first free space (4) and than the second free space (7), with a feed duct being formed in the housing part (3) which - opens either directly into the first free space (4), - or opens into the first free space (4) by way of a third cavity formed between the bearing cover (9) and housing part (3), with lubricating oil being able to be supplied to the feed duct from an intermediate storage means, and to the intermediate storage means oil which is splashed up and collected by a collecting device being fed by way of a supply means to the intermediate storage means, with the annular gap opening in the axial direction into the second free space (7) and opening counter to the axial direction into the first free space (4).

2. A gear unit according to claim 1, characterised in that the centring collar is a hollow-cylindrical region of the bearing cover (9) which protrudes axially from the bearing cover (9).

3. A gear unit according to one of the preceding claims, characterised in that the annular gap has a radial width of less than 3 millimetres.

4. A gear unit according to one of the preceding claims, characterised in that a circular mouth opening of that end of the tube part (10) which is remote from the axial bore is oriented in such a way that the normal vector of the plane receiving the circle of the circular mouth opening is oriented parallel to the direction of gravity.

5. A gear unit according to one of the preceding claims, characterised in that the gear unit is arranged in an industrial installation in such a way that the axis of rotation of the shaft (1) is oriented horizontally and / or the bearing (8) is arranged above the oil level of the lubricating oil which is established when the gear unit is stopped.

6. A gear unit according to one of the preceding claims, characterised in that the inner ring of the bearing is mounted on the shaft (1), with the outer ring of the bearing being axially limited by a securing ring embedded into an annular groove in the housing part (3), with the first free space (4) axially adjoining on one hand the securing ring and on the other hand the disc (13).

7. A gear unit according to one of the preceding claims, characterised in that the first free space (4) is bordered by the securing ring, the disc (13), the shaft (1), the bearing (8) and the housing part (3).

8. A gear unit according to one of the preceding claims, characterised in that the disc (13), together with a further disc (13), mounted on the shaft (1) and connected non-rotatably to the shaft (1), of the labyrinth seal (5), forms the non-contact seal.

9. A gear unit according to one of the preceding claims, characterised in that the first free space (4) is annular in shape, with the ring axis of the annular first free space (4) being oriented coaxially with the axis of rotation of the shaft (1) and / or with the axis of rotation of the bearing.

10. A gear unit according to one of the preceding claims, characterised in that the second free space (7) is annular in shape, with the ring axis of the annular second free space (7) being oriented coaxially with the axis of rotation of the shaft (1) and / or with the axis of rotation of the bearing.

11. A gear unit according to one of the preceding claims, characterised in that the discharge duct is formed between the bearing cover (9) and the housing part (3).

12. A gear unit according to one of the preceding claims, characterised in that the discharge duct is oriented vertically.

13. A gear unit according to one of the preceding claims, characterised in that the axial bore is oriented horizontally.

14. A gear unit according to one of the preceding claims, characterised in that the axial bore is arranged above the oil level which is established in the non-operative state of the gear unit.

15. A gear unit according to one of the preceding claims, characterised in that in the operating state of the gear unit that region of the tube part (10) which is not inserted into the axial bore is acted upon by oil, in particular due to the movement of the oil which is brought about by a gear wheel (2) of the gear unit.