Gearbox with a shaft

Abstract

A gear unit having a shaft, in particular an input shaft, a fan impeller being connected to the shaft in a torsionally fixed manner, a fan hood being connected to the gear unit housing, which at least partially encloses the fan impeller, a separation plate for separating the pressure chamber of the fan from the suction chamber of the fan being connected to the fan hood, where the separation plate has an air intake opening for the fan impeller and is situated on the side of the fan impeller facing axially away from the gear unit, the fan impeller has an upper and a lower cover disk, which are axially set apart from each other, and fan blades are disposed between the cover disks, so that channels are formed, the radial clearance of the air intake opening being disposed within, especially centrally within, the radial clearance region covered by the upper cover disk, and the air intake opening is disposed axially within, especially centrally within, the axial region covered by the upper cover disk.

Claims

1. A gear unit, comprising: a housing; a shaft; a fan including a fan impeller connected to the shaft in a torsionally fixed manner; a fan hood connected to the housing, the housing at least partially enclosing the fan impeller; and a separation plate for separating a pressure chamber of the fan from a suction chamber of the fan, the separation plate being connected to the fan hood, wherein: the separation plate includes an air intake opening for the fan impeller and is situated on a side of the fan impeller facing axially away from the gear unit, the fan impeller has an upper cover disk and a lower cover disk that are axially set apart from each other, fan blades of the impeller are disposed between the cover disks, so that channels are formed, a radial clearance of the air intake opening is disposed within a radial clearance region covered by the upper cover disk, the air intake opening is disposed axially within an axial region covered by the upper cover disk, at least one of the cover disks has a conical shape, and the conically-shaped cover disk extending axially through the air intake opening.

2. The gear unit as recited in claim 1, wherein the shaft is an input shaft.

3. The gear unit as recited in claim 1, wherein: the fan impeller is a radial fan impeller, and the fan blades of the fan impeller are spaced apart from each other at irregular intervals in a circumferential direction.

4. The gear unit as recited in claim 1, wherein: the separation plate abuts the fan impeller, and a clearance is provided that prevents contact between the separation plate and the fan impeller but does not permit any essential back flow from the pressure chamber into the suction chamber.

5. The gear unit as recited in claim 1, wherein: the separation plate abuts the fan impeller, and a gap is provided having a gap width smaller than 10% of an outer diameter of the fan impeller, and larger than 0.1%, of the outer diameter of the fan impeller.

6. The gear unit as recited in claim 1, wherein: the separation plate abuts the fan impeller, and a gap is provided having a gap width smaller than 5% of an outer diameter of the fan impeller, and larger than 0.1%, of the outer diameter of the fan impeller.

7. The gear unit as recited in claim 1, wherein at least one of: at least one of the fan hood and the housing is rectangular, and an outer diameter of the fan impeller is at least one of: greater than a width of the gear unit housing, and smaller than a height of the housing.

8. The gear unit as recited in claim 1, further comprising: air baffles disposed between the fan hood and the gear unit housing in order to one of prevent and reduce turbulence of an air flow emerging from the fan hood, wherein the air baffles are axially set apart from the fan impeller.

9. The gear unit as recited in claim 8, wherein at least one of: the air baffles extend radially from the housing to the fan hood, a channel cross-section increases monotonously from an intake region at the fan impeller, which lies radially farther inward, in a direction of the exit region at the impeller, which lies radially farther outside, the intake region is implemented at an axial position, the intake region area being an area that extends only radially and in a circumferential direction, and the exit region is a surface that extends in the radial direction, in the circumferential direction, and in an axial direction.

10. The gear unit as recited in claim 8, wherein each air baffle extends radially from the housing to the fan hood.

11. The gear unit as recited in claim 1, wherein the fan hood includes a nozzle in an air exit region, so that an emerging air flow flows along the housing.

12. The gear unit as recited in claim 1, further comprising: a cover plate axially set apart from the separation plate, so that an air inflow takes place from a radial direction.

13. The gear unit as recited in claim 12, wherein the cover plate has recesses to allow an additional axially entering air flow.

14. The gear unit as recited in claim 12, further comprising an interlocking protective housing component disposed between the cover plate and the separation plate, and via which the cover plate is retained at the separation plate.

15. The gear unit as recited in claim 1, wherein the separation plate is detachably connected to the fan hood in such a way that fan impellers of different sizes are optionally able to be provided by an exchange of the separation plate.

16. The gear unit as recited in claim 1, wherein at least one of: a cover plate axially set apart from the separation plate, the fan hood is configured as a stamped and bent part, a nozzle is implemented by positioning a fan hood edge in an air exit region, and a setting angle is between 10 and 40.

17. The gear unit as recited in claim 1, wherein an outer radius of the fan impeller is larger than a width of the gear unit and smaller than a height of the gear unit.

18. The gear unit as recited in claim 1, wherein: an outer radius of the fan impeller is smaller than a width of the gear unit and smaller than a height of the gear unit, a radius of an opening of the separation plate being essentially similar to an outer radius of an air intake region, formed by the channels of the fan impeller.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 schematically and in a sectional plan view illustrates a gear unit according to the invention including an attached fan 5.

(2) FIG. 2 shows a cut-away portion from FIG. 1 around fan 5.

(3) FIG. 3 shows a view in the axial direction.

(4) In FIG. 4, the fan hood has been removed in the cross-section according to FIG. 1.

(5) FIG. 5 shows an oblique view of fan 5 from a first direction of view.

(6) FIG. 6 shows an oblique view of fan 5 from another direction of view.

(7) In FIG. 7, in contrast to FIG. 2, separation plate 1 extends radially and axially in the direction of the cover plate in an approximately centrical manner.

DETAILED DESCRIPTION

(8) As shown in the Figures, a fan 5 is connected on input shaft 8 of gear unit 6 in a torsionally fixed manner. A fan hood 9, which surrounds fan 5, is situated on the gear unit housing.

(9) The gear unit is developed as a bevel gear drive, which is why input shaft 8 is supported in a conical pot housing component 11 connected to the housing of gear unit 6.

(10) Fan 5 includes a radial fan impeller, whose fan blades 7 extend radially, in particular exclusively radially. This allows an air supply that is independent of the direction of rotation.

(11) As shown in FIG. 6, radial fan impeller has an upper cover disk 10 and a lower cover disk 13, between which air blades 7 are situated. Upper cover disk 10 and lower cover disk 13 are therefore axially spaced apart from each other. Air blades 7 cover the axial interspace between upper and lower cover disks 10, 13.

(12) Fan hood 9 has a separation plate 1, which extends in the radial direction and is situated at an axial position disposed on the side that is axially facing away from the gear unit having conical pot housing component 11. Separation plate 1 is provided with a centrally situated opening, so that the air is entering from the radial direction. However, the opening in separation plate 1 is so small that the entering air does not reach the outer edge of the fan impeller. The inner diameter of the opening of separation plate 1 is smaller than the maximum outer diameter of fan 5 for this purpose.

(13) By placing fan 5 on the input shaft of the gear unit developed as reduction gears, fan 5 is situated on the shaft that is rotating most rapidly, i.e., on input shaft 8.

(14) Fan hood 9 deflects the air flow supplied by fan 5 from the radial into the axial direction. A nozzle 3, and thus an increased exit speed in the axial exit region, is achieved with the aid of means that cause a restriction.

(15) The exit openings of fan hood 9 are disposed on its side facing away from the input in such a way that the emerging air flow is flowing along the gear unit housing.

(16) However, as can be gathered from the plan view of FIG. 3, the gear unit is basically developed in square form, so that the front side has an essentially rectangular contour. Fan hood 9 has a rectangular form as well, which preferably is rectangular in principle and in particular has a larger cross-sectional area than fan 5 and the gear unit housing, especially in a plan view according to FIG. 3.

(17) The gear unit housing is indicated by dashed lines in FIG. 3.

(18) The maximum outer diameter of fan 5 is greater than the width of the gear unit housing but smaller than the height of the gear unit housing. In the same way the fan hood is broader than the width of the gear unit housing. Therefore the exit opening between fan 5 and the gear unit housing is large, and in particular, corresponds approximately to the difference between the width of fan hood 9 and the width of the gear unit housing.

(19) To prevent turbulence in the air flow supplied by fan 5, fan hood 9 includes radially aligned and radially extending air baffles 4. The rotational pulse of the supplied air flow is therefore reduced. Each air baffle extends from fan hood to the gear unit housing. The radial extension differs depending on the angle at circumference position of individual air baffle 4. That is to say, air baffles 4 act as anti-turbulence plates for the emerging air flow.

(20) The diameter of fan 5 is smaller than the height of the gear unit housing.

(21) Upper cover plate 10 has a conical shape and the cone tip has been removed. The opening thus produced acts as air intake and has a diameter that is less than or equal to the diameter of the air intake opening provided by separation plate 1.

(22) After air has entered the supply channel, delimited by fan blades 7 of fan 5 in the circumferential direction, the channel cross-section Q2 increases starting from intake cross-section Q1 until emerging flow cross-section Q3 has been reached. The increase in cross-section Q2 is preferably monotonous. The fan therefore operates as a diffuser on the one hand, but there is also a conveyance effect in the radial direction because of the development as a radial fan on the other. A relatively high pressure is therefore generated at a relatively low flow rate.

(23) Lower cover disk 13 is preferably planar, i.e., it extends in the radial direction and in the circumferential direction.

(24) As illustrated in FIG. 1, the air intake into the region surrounded by fan module 9 takes place from the radial direction, because the associated opening discharges into the environment in the radial direction.

(25) Using cover plate 12, the entering air is guided radially further toward the inside and axially flows into fan 5 in the opening region of separation plate 1. The air flow radially brought out by fan 5 is deflected by fan hood 9. The air flow exits along the gear unit housing in the axial direction. The constriction causes a jet effect in the exit region of fan hood 9 and thus an increase in the flow rate of the emerging air flow.

(26) The radially directed air intake is possible because of cover plate 12. Input shaft 8 thus is connectible to a driving shaft of an electric motor which drives the gear unit.

(27) The axial region covered by fan hood 9 includes the axial region covered by fan blades 7 and, at least partially, the axial region covered by air baffles 4 as well.

(28) Fan hood 12 and separation plate 1 are able to be produced in one piece, especially from sheet metal, especially steel plate. A particularly simple and cost-effective production is achievable by a production as a stamped and bent part. A two-piece development is advantageous as well, especially if smaller production numbers are involved.

(29) As illustrated in FIG. 3, the fan hood has a rectangular cross-section. The normal of the cross-sectional area is aligned parallel to the axis of the input shaft.

(30) To reduce turbulence losses, air baffles 4 are situated at a distance from fan 5.

(31) Air blades 7 are not uniformly spaced apart from one another in the circumferential direction, so that losses, in particular structure-borne noise and airborne noise losses, are able to be reduced. Nine fan blades 7 are preferably provided.

(32) The hub of the fan impeller has a conical design, and the circumference of the hub increases in the flow direction in order to deflect the air in the radial direction.

(33) As illustrated in FIG. 3, six long air baffles 4 extending in the radial direction are provided in the circumferential direction, and two additional short air baffles 40 which extend in the radial direction and are situated in the upper and lower region of fan hood 9 in each case.

(34) The pressure side and the suction side are therefore separated by separation plate 1. The opening disposed in separation plate 1 in the form of a circle has been cut out for the air entry, and the center point of the circle lies on the imaginary axis of the input shaft.

(35) Nozzle 3 can easily be produced by the placement of the rear edge of fan hood 9. The setting features an angle between 10 and 40.

(36) Cover plate 12 guides the air from radially outside to radially further inside. As a result, any desired attachment may be provided in the axial end region of the input shaft facing away from fan 5 because these attachments, which extend axially farther away from the cover disk and the gear unit, do not affect the air flow to any essential degree because cover plate 12 allows the inflow of the cool ambient air from the radial direction. That is to say, even if the attachments have hot surfaces, no air flow carries heat from the attachments into the fan. In other words, it is therefore possible to place a coupling between the electric drive motor and the gear unit, especially the input shaft of the gear unit. Especially in the case of a fluid coupling disposed on input shaft 8, i.e., a hydraulically operating coupling which has a large extension in the radial direction, the entry of cool air to fan 5 is nevertheless able to be induced by cover plate 12.

(37) Cover plate 12 is connected to fan hood 9 via an interlocking protective housing component 14. Interlocking protective housing component 14 has recesses, which are so small that no adult human finger would fit through them, but which are large enough to let the air flow enter with the least resistance possible.

(38) In addition, cover plate 12 enables an approach of the air from all peripheral angular positions. A uniform distribution is achieved in the process.

(39) Outflow cross-section Q3 is larger than inflow cross-section Q1, preferably 1.1 to 1.3 times larger than inflow cross-section Q1. The vane channel length L2 illustrated in FIG. 4 amounts to between 0.3 to 0.5 times that of fan impeller radius RL. The particular vane channel is delimited by the two most proximate adjacent fan blades 7, at least in the circumferential direction, and in the axial direction by upper cover disk 10 on the one hand, and by lower cover disk 13 on the other.

(40) The separation plate preferably abuts the fan impeller, and a clearance, i.e., a gap, is provided, the gap width of the gap, that is to say, the radial clearance region covered by the gap, being smaller than 10%, especially smaller than 5%, especially smaller than 5% and larger than 0.1%, than the outer diameter of the fan impeller.

(41) As illustrated in the further exemplary embodiment according to FIG. 7, fan 5 has a different design than in FIG. 2. For upper cover disk 10 extends farther in the radially inward direction, and fan 5 then axially projects farther through the recess of separation plate 1. As a result, the axial region covered by fan 5 also covers the axial region of separation plate 1.

(42) In particular, the smallest radial clearance of separation plate 1 is located within the radial clearance region covered by fan 5, especially by its upper cover disk 10.

(43) Furthermore, the axial position of separation plate 1, or the axial region covered by separation plate 1, is located within the axial region covered by fan 5, in particular by its upper cover disk 10.

(44) Preferably, the edge of separation plate 1 that surrounds the air intake opening provided by separation plate 1 is centrally situated in the axial region covered by upper cover disk 10 and centrally in the radial clearance region covered by upper cover disk 10.

(45) In further exemplary embodiments according to the present invention, cover disk 12 is provided with recesses, so that an axial entry of air is made possible in addition.

(46) In additional exemplary embodiments according to the present invention, separation plate 1 is not situated at the inner radius of fan 5 but at the outer radius, in contrast to FIG. 2, and in both cases there is a small clearance in the radial direction between separation plate 1 and fan 5 in order to avoid contact. However, the clearance is selected as small as possible while taking manufacturing tolerances into account, so that the losses by turbulence in the flow, in particular reactive turbulence flows, remain low.

(47) In further exemplary embodiments according to the present invention, separation plate 1 is not developed in one piece with the rest of the fan hood, so that a simple exchange is possible.

LIST OF REFERENCE NUMERALS

(48) 1 separation plate

(49) 2 air supply region

(50) 3 nozzle

(51) 4 air baffle

(52) 5 fan

(53) 6 gear unit

(54) 7 fan blade

(55) 8 input shaft

(56) 9 fan hood

(57) 10 upper cover disk

(58) 11 conical cup housing

(59) 12 cover plate

(60) 13 lower cover disk

(61) 14 engagement protection housing component

(62) 15 edge of gear unit housing

(63) 40 air baffle

(64) A opening cross-section

(65) Q1 inflow cross-section

(66) Q2 channel cross-section

(67) Q3 outflow cross-section