AU2011204855B2

AU2011204855B2 - Cooling device for a gear

Info

Publication number: AU2011204855B2
Application number: AU2011204855A
Authority: AU
Inventors: Ali Kemal Kucukyavuz; Maik Liesegang
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2010-07-22
Filing date: 2011-07-19
Publication date: 2014-07-03
Anticipated expiration: 2031-07-19
Also published as: PL2410209T3; EP2410209A1; SI2410209T1; EP2410209B1; ES2404843T3; HRP20130594T1; AU2011204855A1; CN202301880U

Abstract

COOLING DEVICE FOR A GEAR Abstract A cooling device comprises a bundle (109) of a plurality of heat pipes which can 5 be arranged in each case on a first portion in the region of a lubricant sump (108) and can be connected thermally to this. Evaporation of a heat pipe medium takes place in each case on the first portions of the heat pipes. Moreover, a convection cooling body (110) is provided which can be arranged outside a gear case and which is connected to second portions of the heat pipes. Condensation of the heat pipe medium takes place in each case to on the second portions of the heat pipes. The convection cooling body (1 10) is arranged in a flow region of a fan (111) which has on a first end face (302) an integrated rotationally symmetrical cover disk (301) which is configured as one quarter of a hollow torus. A rounding is thereby formed on the first end face (302), on an outer cylindrical surface area (304) of the fan which extends between the first end face (302) and a second is end face (303). 208-1 232 o0 205 208 o o o o 251 o0o 10 o 0 o oo o 0

Description

S&F Ref: P004353 AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name and Address Siemens Aktiengesellschaft, of Wittelsbacherplatz 2, of Applicant: 80333, Munchen, Germany Actual Inventor(s): Ali Kemal Kucukyavuz Maik Liesegang Address for Service: Spruson & Ferguson St Martins Tower Level 35 31 Market Street Sydney NSW 2000 (CCN 3710000177) Invention Title: Cooling device for a gear The following statement is a full description of this invention, including the best method of performing it known to me/us: 5845c(5458159_1) Cooling device for a gear Gears are often of central importance in industrial working and manufacturing processes. Industrial gears must fulfill a broad range of complex requirements. For example, one of these requirements is reliable functioning over a long period of use with minimal outlay in maintenance terms. Gear failures detrimental to industrial working and manufacturing processes may become costly, for example because of expensive standstill times. 10 DE 10 2006 020 801 Al. describes a construction kit of gear cooling devices, in which a plurality of covers can be combined with a plurality of modules to form a multiplicity of cooling devices of different cooling capacity for mounting on a gear. The cooling devices are 15 placed onto the mounting orifice of the gear and in each case receive lubricating oil splashing inside the gear and transfer the heat contained in the lubricating oil to an external cooling circuit. Both DE 36 06 963 C2 and US 5,072,784 disclose a gear with '19 a heat exchanger which forms a case cover and is connected to a lubricant pump, arranged inside a gear case, for conveying lubricant out of a lubricant sump. The lubricant pump is arranged in a lubricant distribution system between the lubricant sump and the heat exchanger. 25 DE 103 15 684 Al discloses a gear in which a tubular heat exchanger is used as an oil cooler which is integrated into a gear case. By means of an oil pump which follows the tubular heat exchanger, oil is sucked out of an oil sump and, in the process, flows around the tubular heat 2P exchanger. After the oil has been cooled in the tubular - 2 heat exchanger, the oil is conveyed to lubrication points inside the gear by the oil pump. DE 10 2004 022 863 Al describes a gear which has a case closed sealingly and releasably by means of a case cover. Furthermore, the cover comprises a cooling device which has cooling fingers or cooling ribs and in which air is used as cooling medium. In the gear known from DE 10 2007 024 512 Al, a cooling cartridge formed from elongate cooling tubes is plugged \0 through an orifice in a gear case and is screwed into the orifice by means of a basic body from which the cooling tubes emanate. The cooling cartridge is arranged in the region of an oil sump inside the gear. This sometimes means, however, that there are restrictions in terms of I5 the dimensioning and selection of cooling devices which can be used. US 6,830,096 describes. a differential gear in which a heat pipe extends first horizontally through a lubricant sump and then vertically inside a case of the differential iP gear. Outside the case, the heat pipe has fastened to it cooling ribs, via which heat exchange with the surroundings of the differential gear takes place. DE 40 10 333 Al discloses a lubricating oil cooling device of a power transfer system which comprises a case for the W5 reception of at least two intermeshing gearwheels and of lubricating oil. In this case, only part of each gearwheel dips into the lubricating oil. A heat pipe provided with a heating and a cooling section is fastened to the case. The case comprises an oil tank, which is arranged laterally 30 with respect to a gearwheel and which is supplied with lubricating oil by the action of centrifugal force, and, for the oil tank, a connecting orifice which, when the 3 gearwheels are stationary, is located at a point lying above a lubricating oil level. The heating section of the heat pipe is inserted through the connecting orifice into the oil tank. It is an object of the invention to improve upon the prior art or at least to provide a useful alternative thereto. A preferred embodiment aims to specify a cooling device for a gear which, even with compact dimensions, allows a rapid discharge of large quantities of heat. The cooling device according to the present disclosure is suitable for a gear which has at least one drive shaft and one output shaft, which pass through a respective orifice on a gear case, and a gearwheel connected to the drive shaft and a gearwheel connected to the output shaft, said gearwheels being in engagement indirectly or directly with one another. The cooling device comprises a bundle of several heat pipes which can be arranged in each case on a first portion in the region of a lubricant sump and which can be connected thermally to this. Evaporation of a heat pipe medium in each case takes place on the first portions of the heat pipes. Moreover, a convection cooling body is provided which can be arranged outside the gear case and which is connected to second portions of the heat pipes. Condensation of the heat pipe medium takes place in each case on the second portions of the heat pipes. The convection cooling body is arranged in a flow region of a fan which has on a first end face an integrated rotationally symmetrical cover disk which is configured as an outer quarter of a hollow torus. A rounding is thereby formed on the first end face, on an outer cylindrical surface area of the fan which extends between the first end face and the second end face, whereby, by virtue of the cover disk, the fan has in cross section a portion which is in the form of a quarter circle and which the outer cylindrical surface area adjoins. A compact and efficient cooling device with an extremely effective fan can thereby be implemented. The present invention is explained in more detail below by means of exemplary embodiments, with reference to the drawing in which: Figure 1 shows a cooling device for a gear with one bevel wheel stage and with three spur wheel stages in longitudinal section, Figure 2 shows the gear according to figure 1 in a view from a drive-side end face, Figure 3 shows a portion of a heat pipe bundle of the cooling device illustrated in figure 1, 4 Figure 4 shows a fan for the cooling devices according to figure 1 in a perspective illustration, Figure 5 shows the fan according to figure 4 in cross section, Figure 6 shows a cooling device for the gear with three planet stages and with one bevel wheel stage, Figure 7 shows the gear according to figure 6 in a cross-sectional illustration in the region of a first heat pipe bundle which is arranged between a first and a second planet stage, Figure 8 shows the gear according to figure 6 in a cross-sectional illustration in the region of a second - 5 heat pipe bundle which is arranged on the bevel wheel stage, Figure 9 shows a perspective illustration of the first heat pipe bundle of the cooling device illustrated in figure 6, Figure 10 shows a perspective illustration of the second heat pipe bundle of the cooling device illustrated in figure 6. Figure 1 and 2 illustrate a gear for industrial applications, which comprises a drive shaft 102 and an output shaft 103, which pass in each case through an orifice on a gear case 101, and also a heat pipe-based cooling device. The drive shaft 102 is connected to a bevel wheel stage 104 which comprises a bevel wheel and a bevel pinion. The bevel wheel stage 104 is connected via a first spur wheel stage 105 and a second spur wheel stage 106 to a third spur wheel stage 107 which is connected fixedly in terms of rotation to the output shaft 103. The first spur wheel stage 104 comprises a spur wheel which is connected fixedly in terms of rotation to the bevel pinion of the bevel wheel stage 104. The spur wheel of the first spur wheel stage 104 meshes with a pinion of a gearwheel/pinion combination of the second spur wheel stage 105, the gearwheel of which meshes, in turn, with a spur wheel of the third spur wheel stage 107. A bundle 109 of several heat pipes of the cooling device for a gear is arranged on each of the two sides of the drive shaft. The heat pipes are in each case arranged at a first end in the region of a lubricant sump 108 and are coupled thermally to lubricant in the lubricant sump 108. Outside the gear case 101, two convection cooling bodies 110 of the cooling device are arranged (cf. also figure 3) - 6 at second ends of the heat pipes inside a motor lantern 112. Evaporation of a heat pipe medium takes place in each case at the first ends of the heat pipes, while condensation of the heat pipe medium takes place in each case at- the second ends of the heat pipes. The convection cooling bodies 110 have in each case a plurality of cooling lamellae. A convection cooling body 110 can in principle also be integrated into a case cover. In the present exemplary embodiment, a fan 111 of the tO cooling device, in the flow region of which fan the convection cooling bodies 110 are arranged, is connected fixedly in terms of rotation to the drive shaft 102. An electric fan drive may thereby be dispensed with. The fan 111 could in principle also be driven alternatively by the 15 output shaft 103. Furthermore, fans which are temperature regulated in terms of their rotational speed may also be provided on the convection cooling bodies 110. In the gearwheel illustrated in figures 1 and 2, only the two heat pipe bundles 109 with the convection cooling bodies 7p 110 and the fan 111 are provided for cooling. A fan for a cooling device according to figure 1 and 2 is illustrated in detail in figure 4 and 5. The fan has on a first end face 302 an integrated rotationally symmetrical cover disk 301 which is configured as one quarter of a 25 hollow torus. A rounding is thereby formed on the first end face 302, on an outer cylindrical surface area 304 of the fan which extends between the first end face 302 and a second end face 303. By virtue of the cover disk 301, the fan has in cross section a portion 305 which is in the 30 form of a quarter circle and which the outer cylindrical surface area 304 adjoins. Furthermore, the fan has in an inner radial portion a disk 306 with a plurality of passage orifices 307 arranged so - 7 as to be offset with respect to one another by a first predeterminable angle. In the present exemplary embodiment, the passage orifices 307 are in each case arranged so as to be offset with respect to one another by S 90 degrees. Moreover, the disk 306 is connected to the cover disk 301 by means of a plurality of radially outward-extending lamellae 308 arranged so as to be offset with respect to one another by a second predeterminable angle. According to figure 9, the lamellae 308 are in each 10 case arranged so as to be offset with respect to one another by 30 degrees. Figure 6 illustrates a gear for industrial applications, which comprises three planet stages 202-204 and one bevel wheel stage 205, which are arranged in a common gear case 16 201, and also a heat pipe-based cooling device. The planet stages comprise in each case a stationary ring wheel 221, 231, 241, a planet carrier 222, 232, 242 receiving a plurality of planets, and a sun wheel 223, 233, 243. The planet carrier 222 of the first planet stage 202 is 20 connectable to a drive shaft, while the sun wheel 243 of a third planet stage 204 is connected fixedly in terms of rotation to a bevel wheel 251 of the bevel wheel stage 205 arranged on the output side. The sun wheel 223 of the first planet stage 202 is connected to the planet carrier 25 232 of a second planet stage 203, the sun wheel 233 of which is connected in turn to the planet carrier 242 of the third planet stage 204. As may also be gathered from the cross-sectional illustration according to figure 7, a first heat pipe 30 bundle 206 is arranged axially between the first planet stage 202 and the second planet stage 203. A first ring like portion of the first heat pipe bundle 206 is arranged inside the gear case 201 and radially surrounds the planet carrier 232 of the second planet stage 203. The first -8 ring-shaped portion of the first heat pipe bundle 206 has adjoining it a second portion which ends outside the gear case 201 (see also figure 9). A convection cooling body 208 is arranged at one end of the second portion. The 5 convection cooling body 208 is arranged in a flow region of a fan which is connected to a drive shaft or output shaft of the gear and which is configured according to figure 4 and 5. At least part of the first portion of the first heat pipe 10 bundle 206 is dipped into a lubricant sump on a bottom portion of the gear case 201 and is thermally coupled to lubricant in the lubricant sump. Evaporation of a heat pipe medium takes place on the first portion of the first heat pipe bundle 206, while condensation of the heat pipe 16 medium takes place on the second portion. It may be gathered from the cross-sectional illustration according to figure 8 that a second U-shaped heat pipe bundle 207 is arranged on the bevel wheel stage 205. The bevel wheel stage 205 comprises in addition to the bevel IP wheel 251 a bevel pinion on 252 which is connected to an output shaft and is in engagement with the bevel wheel 251. The second heat pipe bundle 207 comprises a first half-ring-like portion which extends inside the gear case 201 and radially surrounds the bevel wheel 251. The first 6 half-ring-shaped portion of the second heat pipe bundle 207 has adjoining it two second portions which end outside the gear case 201 (see also figure 10) . A convection cooling body 208 is arranged in each case at one end of the second portion. The convection cooling bodies 208 are ;0 in each case arranged in a flow region of a fan which is connected to a drive shaft or output shaft of the gear and is configured according to figure 4 and 5.

- 9 The first portion of the second heat pipe bundle 207 is dipped into a lubricant sump on the bottom portion of the gear case 201 and is thermally coupled to lubricant in the lubricant sump. In a similar way to the statements made above, evaporation of a heat pipe medium takes place at the first portion of the second heat pipe bundle 207, while the heat pipe medium condenses on the two second portions. The use of the present invention is not restricted to the tO exemplary embodiments described.

Claims

1. A cooling device for a gear which has at least one drive shaft and one output shaft which pass through a respective orifice on a gear case, and a gearwheel connected to the drive shaft and a gearwheel connected to the output shaft, said gearwheels being in engagement indirectly or directly with one another, including - a bundle of a plurality of heat pipes which are arrangeable in each case on a first portion in the region of a lubricant sump and which are thermally connectable to the lubricant sump, evaporation of a heat pipe medium taking place in each case on the first portions of the heat pipes, - a convection cooling body arrangeable outside the gear case and which is connected to second portions of the heat pipes, condensation of the heat pipe medium taking place in each case on the second portions of the heat pipes, - a fan, in the flow region of which the convection cooling body is arranged, the fan having on a first end face an integrated rotationally symmetrical cover disk which is configured as an outer quarter of a hollow torus, with the result that a rounding is formed on the first end face, on an outer cylindrical surface area of the fan which extends between the first end face and a second end face, whereby, by virtue of the cover disk, the fan has in cross section a portion which is in the form of a quarter circle and which the outer cylindrical surface area adjoins.

2. The cooling device as claimed in claim 1, in which the fan has in an inner radial portion of a disk with a plurality of passage orifices arranged so as to be offset with respect to one another by a first predeterminable angle, and in which the disk is connected to the cover disk by means of a plurality of radially outward-extending lamellae arranged so as to be offset with respect to one another by a second predeterminable angle.

3. The cooling device as claimed in claim 1 or 2, in which the fan is connectable to the drive shaft or output shaft.

4. The cooling device as claimed in claim 3, in which the fan is connectable fixedly in terms of rotation to the drive shaft or output shaft.

5. The cooling device as claimed in claim 1 or 2, in which the fan is temperature-regulated in terms of its rotational speed. 11

6. The cooling device as claimed in any one of claims 1 to 5, in which the convection cooling body is integrated into a case cover.

7. The cooling device as claimed in any one of claims 1 to 6, in which the convection cooling body has cooling lamellae.

8. The cooling device as claimed in any one of claims I to 6, in which only the bundle of a plurality of heat pipes and the fan are provided for cooling the gear.

9. A cooling device substantially as hereinbefore described with reference to any one of the embodiments as that embodiment is shown in the accompanying drawings. Siemens Aktiengesellschaft Patent Attorneys for the Applicant/Nominated Person SPRUSON & FERGUSON