CN117803698A

CN117803698A - Final driving device for wheeled tractor

Info

Publication number: CN117803698A
Application number: CN202410232398.5A
Authority: CN
Inventors: 王鹏; 王斌; 王天博
Original assignee: Weifang Huaxia Tractor Manufacturing Co ltd
Current assignee: Weifang Huaxia Tractor Manufacturing Co ltd
Priority date: 2024-03-01
Filing date: 2024-03-01
Publication date: 2024-04-02

Abstract

The invention and the tractor transmission field provide a wheeled tractor final transmission device, including final transmission shell, one end of the final transmission shell is provided with a connecting end cover, the connecting end cover and the final transmission shell are detachably connected through a fixing bolt, one end of the connecting end cover is provided with an input shaft, one end of the input shaft positioned in the connecting end cover is connected with a planetary reduction mechanism, the extension shell is symmetrically provided with a heat radiation opening, the final transmission shell is symmetrically provided with a heat absorbing plate, the heat absorbing plate is provided with a self-driven opening and closing mechanism, one end of the self-driven opening and closing mechanism is connected with a heat radiation opening sealing mechanism, and the invention has the beneficial effects that: the device of the application is stable in overall structure, the two-stage gear reduction structure realizes large transmission ratio, large torque transmission is realized, and the device is started to automatically open a heat dissipation function, and the device has the functions of automatically opening and closing a heat dissipation port, so that heat dissipation of the device is more automatic, and the heat dissipation port can be prevented from entering dust.

Description

Final driving device for wheeled tractor

Technical Field

The invention relates to the technical field of tractor transmission, in particular to a final transmission device of a wheeled tractor.

Background

At present, in the high-power wheeled tractor products produced in China, a final transmission assembly of a transmission system configuration mostly adopts a single-stage planetary gear device, namely, a planetary gear is driven by a sun gear, so that the power output of a planetary carrier is realized. Such devices have difficulty achieving large ratio outputs, and thus have the problem of being unable to carry large torque outputs, etc.

With the rapid development of domestic wheeled tractors, especially in northwest, north China and northeast China, the demands of users on high-power wheeled tractors are increasing, and the market demands of the high-power wheeled tractors are increasing. The final transmission assembly of the high-power wheeled tractor transmission system sold in the domestic market at present adopts a single-stage planetary gear structure, and the final transmission assembly is difficult to realize high transmission ratio and high torque output. With the continuous upgrading of high-power wheeled tractor technique, the final drive assembly that adopts single-stage planet row device hardly satisfies its intensity and rigidity etc. requirement, simultaneously, current wheeled tractor is through the output shaft input power with the motor to the incasement, finally through the power of output high torque, and current casing mostly is sealed setting, can produce a large amount of heats in the long-time working process, and the heat is too much can lead to the internal part to damage, reduces the life of equipment.

For the problems in the related art, no effective solution has been proposed at present.

Disclosure of Invention

Aiming at the defects existing in the prior art, the invention aims to provide a final transmission device of a wheeled tractor.

In order to achieve the above purpose, the invention is realized through the following technical scheme that the final transmission device of the wheeled tractor comprises a final transmission shell, one end of the final transmission shell is provided with a connecting end cover, the connecting end cover is detachably connected with the final transmission shell through a fixing bolt, one end of the connecting end cover is provided with an input shaft, the other end of the final transmission shell is integrally connected with an extension shell, the input shaft is positioned in the connecting end cover and is fixedly sleeved with an installation sleeve, air inlet blades are uniformly arranged on the installation sleeve, the connecting end cover is symmetrically provided with an air inlet, the air inlet is provided with a dustproof net, one end of the input shaft positioned in the connecting end cover is connected with a planetary reduction mechanism, the other end of the planetary reduction mechanism is connected with an output shaft, the extension shell is provided with a stable supporting structure used for the penetration of the output shaft, the extension shell is symmetrically provided with a heat dissipation opening, the final transmission shell is symmetrically internally provided with a heat absorption plate, the heat absorption plate is internally provided with a self-driven opening and closing mechanism, and one end of the self-driven opening and closing mechanism is connected with a heat dissipation opening sealing mechanism.

Preferably, the planetary reduction mechanism comprises a first gear ring, a supporting ring and a second gear ring, wherein the first gear ring is fixed in the connecting end cover, a first transmission gear connected with the end part of the input shaft is arranged at the center of the first gear ring, three positioning columns are fixedly arranged on the first gear ring, and three first planetary gears meshed with the first gear ring are arranged outside the first transmission gear; the support ring is provided with three connecting shafts which are rotationally connected with the first planet wheel, connecting rods are connected to the three connecting shafts, a rotating shaft is arranged at the cross connection position of the three connecting rods, a second transmission gear is arranged on the rotating shaft, the second gear ring is located on one side of the first gear ring, a positioning hole matched with the positioning column is formed in the second gear ring, the second transmission gear extends to the center of the second gear ring, three second planet wheels are arranged in the second gear ring, the second planet wheels are meshed with the second gear ring and the second transmission gear, a supporting rod is connected to the second planet wheels through the connecting shafts, a main shaft is connected to the other end of the supporting rod together, a third transmission gear is arranged on the main shaft, and the other end of the third transmission gear is connected with the output shaft.

Preferably, the heat dissipation port sealing mechanism comprises an arc-shaped sealing plate, two ends of the arc-shaped sealing plate are respectively provided with a first connecting side plate and a second connecting side plate, a first guide hole is formed in the first connecting side plate, a first guide column connected with the inner wall of the extension shell is arranged in the first guide hole in a penetrating mode, and a first positioning spring is sleeved outside the first guide column.

Preferably, the self-driven opening and closing mechanism comprises an outer cylinder body arranged on the heat absorbing plate, a piston is arranged in the outer cylinder body, the outer cylinder body is divided into a gasification chamber and a movable chamber by the piston, gasification liquid is arranged in the gasification chamber, limit baffles are symmetrically arranged in the gasification chamber, a second guide column movably penetrating through the outer cylinder body is arranged at the other end of the piston, the second guide column is connected with the second connecting side plate, and a second positioning spring is arranged at one end of the second guide column in the movable chamber.

Preferably, the stable supporting structure comprises an outer mounting ring, an inner movable ring is arranged in the outer mounting ring, and an antifriction layer is arranged in the inner movable ring.

Preferably, the inner wall of the outer mounting ring is provided with a guide circular groove, a plurality of guide balls are uniformly arranged in the guide circular groove, the guide balls are connected with the outer wall of the inner movable ring through connecting blocks, and auxiliary inclined rods connected with the outer wall of the inner movable ring are arranged on the two sides of the connecting blocks.

Preferably, the first gear ring and the second gear ring are respectively provided with a lubrication cavity, the lubrication cavities are internally provided with support columns, the bottoms of the lubrication cavities are respectively provided with four lubrication ports, and one ends of the lubrication ports, which are positioned in the lubrication cavities, are respectively provided with a moisture absorption sponge.

The invention provides a final transmission device of a wheeled tractor, which has the following beneficial effects:

the utility model provides a device, including fixed bolt's effect, the final drive casing is connected fixedly with the connection end cover, the input shaft input power of setting, through the effect of installation cover and air inlet blade, realize automatic radiating effect at the during operation, the air inlet cooperation dust screen of setting, also can block the entering of dust when admitting air, the power of input shaft input is reduced to the planetary reduction mechanism of setting, make it produce bigger moment of torsion, stability when the output shaft transmission has been guaranteed to stable bearing structure who sets up simultaneously, the thermovent cooperation self-driven mechanism that opens and shuts and thermovent sealing mechanism of setting, when the equipment during operation, its inside temperature passes through the absorber plate and absorbs, after the temperature reaches certain degree, then automatically open thermovent and dispel the heat the work, then the temperature decline, automatically, the thermovent is closed, the device of this application simple structure, and convenient use, holistic stable structure, the structure of two-stage gear reduction has realized big transmission ratio, the transmission of big moment of torsion, and the automatic function of opening and closing thermovent when equipment starts, the function of possessing automatic opening and closing thermovent, the thermovent of messenger's equipment more automaticly, can prevent thermovent entering dust.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a front view of a final drive of a wheeled tractor according to an embodiment of the invention;

FIG. 2 is a schematic illustration of the structure of a final drive of a wheeled tractor according to an embodiment of the invention;

FIG. 3 is a schematic view of the planetary reduction mechanism in a final drive of a wheeled tractor according to an embodiment of the present invention;

FIG. 4 is a schematic illustration of a thermal interface seal mechanism in a final drive of a wheeled tractor according to an embodiment of the invention;

FIG. 5 is a schematic view of the self-driven opening and closing mechanism in a final drive of a wheeled tractor according to an embodiment of the invention;

FIG. 6 is a schematic structural view of a stabilizing support structure in a final drive of a wheeled tractor according to an embodiment of the invention;

fig. 7 is a schematic view showing the internal structures of a first ring gear and a second ring gear in a final drive of a wheeled tractor according to an embodiment of the present invention.

In the figure:

1. a final drive housing; 2. connecting an end cover; 3. an input shaft; 4. a fixing bolt; 5. an extension housing; 6. a mounting sleeve; 7. an air inlet vane; 8. an air inlet; 9. a dust screen; 10. a planetary reduction mechanism; 11. an output shaft; 12. stabilizing the support structure; 13. a heat radiation port; 14. a self-driven opening and closing mechanism; 15. a heat dissipation port sealing mechanism; 16. a first gear ring; 17. a first transmission gear; 18. positioning columns; 19. a first planet wheel; 20. a connecting rod; 21. a rotating shaft; 22. a transmission gear II; 23. a support ring; 24. a second gear ring; 25. positioning holes; 26. a planet wheel II; 27. a connecting shaft; 28. a support rod; 29. a main shaft; 30. a transmission gear III; 31. an arc-shaped sealing plate; 32. connecting a first side plate; 33. connecting a second side plate; 34. a first guide hole; 35. a first guide post; 36. positioning a first spring; 37. a heat absorbing plate; 38. an outer cylinder; 39. a piston; 40. a gasification bin; 41. a movable bin; 42. a limit baffle; 43. a second guide post; 44. positioning a second spring; 45. an outer mounting ring; 46. an inner movable ring; 47. an antifriction layer; 48. a guide circular groove; 49. a connecting block; 50. a guide ball; 51. an auxiliary diagonal rod; 52. a lubrication cavity; 53. a support column; 54. a lubrication port; 55. moisture absorbing sponge.

Detailed Description

The invention is further described in connection with the following detailed description, in order to make the technical means, the creation characteristics, the achievement of the purpose and the effect of the invention easy to understand.

Referring to fig. 1-7, a final transmission device for a wheeled tractor according to an embodiment of the present invention includes a final transmission housing 1, one end of the final transmission housing 1 is provided with a connection end cover 2, the connection end cover 2 is detachably connected with the final transmission housing 1 through a fixing bolt 4, the final transmission housing 1 and the connection end cover 2 are fixedly connected through the effect of the fixing bolt 4, an input shaft 3 is installed at one end of the connection end cover 2, the other end of the final transmission housing 1 is integrally connected with an extension housing 5, the input shaft 3 is fixedly sleeved with a mounting sleeve 6 in the connection end cover 2, air inlet vanes 7 are uniformly installed on the mounting sleeve 6, air inlets 8 are symmetrically opened on the connection end cover 2, a dust screen 9 is provided on the air inlets 8, the input shaft 3 is arranged to input power, through the functions of the mounting sleeve 6 and the air inlet blades 7, the automatic heat dissipation effect is realized during operation, the arranged air inlet 8 is matched with the dust screen 9, dust can be prevented from entering during air inlet, one end of the input shaft 3 positioned in the connecting end cover 2 is connected with the planetary reduction mechanism 10, the other end of the planetary reduction mechanism 10 is connected with the output shaft 11, the extension shell 5 is provided with the stable supporting structure 12 used for the penetration of the output shaft 11, the extension shell 5 is symmetrically provided with the heat dissipation opening 13, the final transmission shell 1 is symmetrically provided with the heat absorption plate 37, the heat absorption plate 37 is provided with the self-driven opening and closing mechanism 14, one end of the self-driven opening and closing mechanism 14 is connected with the heat dissipation opening sealing mechanism 15, the arranged planetary reduction mechanism 10 reduces the power input by the input shaft 3 to generate larger torque, the stability when the output shaft 11 transmission has been guaranteed to stable bearing structure 12 that sets up simultaneously, the thermovent 13 cooperation self-driven mechanism 14 that opens and shuts and thermovent sealing mechanism 15 that sets up, when equipment during operation, its inside temperature is absorbed through absorber plate 37, after the temperature reaches certain degree, then automatic open thermovent 13 carries out the work of dispelling the heat, when equipment stopped, then the temperature decline, automatic closing thermovent 13, the device of this application simple structure, and convenient to use, holistic stable in structure, the big transmission ratio has been realized to the structure of two-stage gear reduction, realized big torque transmission, and automatic opening the heat dissipation function when equipment starts, possess the function of automatic opening and closing thermovent 13, make the heat dissipation of equipment more automatic, can prevent thermovent 13 entering dust.

In an embodiment, referring to fig. 3 of the specification, the planetary reduction mechanism 10 includes a first gear ring 16, a supporting ring 23, and a second gear ring 24, where the first gear ring 16 is fixed in the connecting end cover 2, a first transmission gear 17 connected to an end of the input shaft 3 is disposed at a center of the first gear ring 16, three positioning posts 18 are fixedly disposed on the first gear ring 16, and three first planetary gears 19 meshed with the first gear ring 16 are disposed outside the first transmission gear 17; the support ring 23 is provided with three connecting shafts which are rotationally connected with the first planetary gear 19, connecting rods 20 are connected to the three connecting shafts, a rotating shaft 21 is arranged at the cross connection position of the three connecting rods 20, a transmission gear II 22 is arranged on the rotating shaft 21, a gear ring II 24 is positioned on one side of the gear ring I16, a positioning hole 25 matched with the positioning column 18 is formed in the gear ring II 24, the transmission gear II 22 extends to the center of the gear ring II 24, three second planetary gears 26 are arranged in the gear ring II 24, the second planetary gears 26 are meshed with the second planetary gears 24 and the second transmission gear 22, a support rod 28 is connected to the second planetary gears 26 through connecting shafts 27, a main shaft 29 is connected to the other end of the support rod 28, a transmission gear III 30 is arranged on the main shaft 29, and the other end of the transmission gear III 30 is connected with the output shaft 11. Through the first 17 drive of drive gear that sets up with its meshed planet wheel first 19, the cooperation connecting rod 20 makes its rotation in ring gear first 16, the stability of three connecting rod 20 can be guaranteed to holding ring 23, the drive gear second 22 is driven to the pivot 21 again, drive gear second 22 then drives three planet wheel second 26 and rotate in ring gear second 24, even cooperate bracing piece 28 through the connecting axle 27 that sets up, realize the rotation of drive gear third 30 on the main shaft 29, finally drive output shaft 11 and rotate, accomplish the speed reduction function, increase its moment of torsion, and holistic structure is more reliable and stable, the installation is also more convenient.

In an embodiment, referring to fig. 4 and 5 of the present disclosure, the heat dissipation port sealing mechanism 15 includes an arc sealing plate 31, two ends of the arc sealing plate 31 are respectively provided with a first connecting side plate 32 and a second connecting side plate 33, a first guide hole 34 is formed on the first connecting side plate 32, a first guide post 35 connected to the inner wall of the elongated housing 5 is disposed in the first guide hole 34 in a penetrating manner, a positioning spring 36 is sleeved outside the first guide post 35, the self-driven opening and closing mechanism 14 includes an outer cylinder 38 mounted on the heat absorbing plate 37, a piston 39 is disposed in the outer cylinder 38, the piston 39 divides the outer cylinder 38 into a gasification chamber 40 and a movable chamber 41, gasification liquid is disposed in the gasification chamber 40, limit baffles 42 are symmetrically disposed in the gasification chamber 40, a second guide post 43 movably penetrating through the outer cylinder 38 is disposed at the other end of the piston 39, the second guide post 43 is connected to the second connecting side plate 33, and a positioning spring 44 is disposed at one end of the second guide post 43 located in the movable chamber 41. When the device works, a part of heat is transferred to the outer cylinder 38 through the heat absorbing plate 37, so that gasification liquid in the gasification bin 40 is gasified, the pressure in the gasification bin 40 is increased, the pushing piston 39 is pushed forward, the guide post II 43 pushes the connecting side plate II 33 to push forward, the connecting side plate II 33 is fixedly connected with the arc-shaped sealing plate 31, finally, the arc-shaped sealing plate 31 is driven to push, the first guide post 35 is matched, the positioning spring 36 is contracted, the heat dissipation opening 13 is opened, and the opening work is completed, otherwise, the device does not work, the temperature is reduced, the gasification liquid is liquefied, the pressure is reduced, and the arc-shaped sealing plate 31 is ensured to be positioned at the heat dissipation opening 13 through the matching of the first guide post 35, the first positioning spring 36, the second guide post 43 and the second positioning spring 44, and the heat dissipation opening 13 is in a sealing state.

In an embodiment, referring to fig. 6 of the drawings, the stable supporting structure 12 includes an outer mounting ring 45, an inner moving ring 46 is disposed in the outer mounting ring 45, an antifriction layer 47 is disposed in the inner moving ring 46, a guiding circular groove 48 is formed on an inner wall of the outer mounting ring 45, a plurality of guiding balls 50 are uniformly disposed in the guiding circular groove 48, the guiding balls 50 are connected with an outer wall of the inner moving ring 46 through a connecting block 49, and auxiliary diagonal rods 51 connected with an outer wall of the inner moving ring 46 are disposed on two sides of the connecting block 49 on the guiding balls 50. The rotation of the inner movable ring 46 is realized and the stability is extremely high by the cooperation of the guide balls 50 provided in the guide circular groove 48 and the connection by the auxiliary diagonal rod 51 and the connection block 49.

In an embodiment, referring to fig. 7 of the specification, the first ring gear 16 and the second ring gear 24 are both provided with a lubrication cavity 52, a support column 53 is disposed in the lubrication cavity 52, four lubrication ports 54 are provided in an inner bottom of the lubrication cavity 52, and a moisture absorption sponge 55 is disposed at one end of the lubrication ports 54 located in the lubrication cavity 52. When the planetary gear I19 and the planetary gear II 26 pass through the lubrication port 54 in real time, the lubricating oil dripping from the moisture absorption sponge 55 can be contacted to play a role in lubrication, and meanwhile, the lubricating oil also has a certain heat absorption effect, so that the heat dissipation property is improved.

During practical application, the final transmission shell 1 is connected and fixed with the connecting end cover 2 through the effect of the fixing bolt 4, the input shaft 3 of setting inputs power, through the effect of the installation cover 6 and the air inlet blade 7, realize automatic radiating effect at the during operation, the air inlet 8 cooperation dust screen 9 of setting, also can block the entering of dust when admitting air, the power that the planetary reduction gear 10 of setting was input with the input shaft 3 reduces, make it produce bigger moment of torsion, stability when the output shaft 11 is transmitted has been guaranteed to stable bearing structure 12 of setting simultaneously, the thermovent 13 cooperation self-driven mechanism 14 and thermovent sealing mechanism 15 of opening and shutting that sets up, when the equipment during operation, the temperature of its inside is absorbed through the absorber plate 37, then automatic opening thermovent 13 carries out radiating operation after the temperature reaches certain degree, when equipment stops, then the temperature drops, automatically closing thermovent 13, the device of this application simple structure, convenient use, the whole stable structure, the structure of two-stage gear reduction has realized big transmission ratio, realized big moment of torsion transmission, and automatic opening function when equipment starts, possess automatic opening and close the function of thermovent 13, the thermovent 13 of messenger, can prevent that the thermovent 13 from entering into the thermovent.

Although the present disclosure describes embodiments, not every embodiment is described in terms of a single embodiment, and such description is for clarity only, and one skilled in the art will recognize that the embodiments described in the disclosure as a whole may be combined appropriately to form other embodiments that will be apparent to those skilled in the art.

Claims

1. The utility model provides a final drive device of wheeled tractor, its characterized in that, including final drive casing (1), the one end of final drive casing (1) is equipped with connection end cover (2), connection end cover (2) with can dismantle through fixing bolt (4) between final drive casing (1), input shaft (3) are installed to the one end of connection end cover (2), the other end body coupling of final drive casing (1) has extension casing (5), input shaft (3) are located connection end cover (2) internal fixation cover is equipped with installation cover (6), evenly install inlet vane (7) on installation cover (6), inlet port (8) have been seted up to symmetry on connection end cover (2), be equipped with dust screen (9) on inlet port (8), one end that input shaft (3) are located in connection end cover (2) is connected with planetary reduction gears (10), the other end of planetary reduction gears (10) is connected with output shaft (11), be equipped with on extension casing (5) be used for stable bearing structure (12) that output shaft (11) run through, extension casing (5) are equipped with symmetrical heat absorption plate (13), the self-driven opening and closing mechanism (14) is mounted on the heat absorbing plate (37), and one end of the self-driven opening and closing mechanism (14) is connected with the heat dissipation opening sealing mechanism (15).

2. A final drive of a wheeled tractor according to claim 1, characterized in that the planetary reduction mechanism (10) comprises a first gear ring (16), a supporting ring (23) and a second gear ring (24), wherein the first gear ring (16) is fixed in the connecting end cover (2), a first transmission gear (17) connected with the end of the input shaft (3) is arranged at the center of the first gear ring (16), three positioning posts (18) are fixedly arranged on the first gear ring (16), and three first planetary gears (19) meshed with the first gear ring (16) are arranged outside the first transmission gear (17); be provided with on the support ring (23) three with the connecting axle that planet wheel one (19) rotates to be connected, and all be connected with connecting rod (20) on the three connecting axle, the cross connection department of three connecting rod (20) is provided with pivot (21), be equipped with drive gear two (22) on pivot (21), gear ring two (24) are located one side of gear ring one (16), just establish on gear ring two (24) with reference column (18) assorted locating hole (25), just drive gear two (22) extend to the center department of gear ring two (24), be equipped with three planet wheel two (26) in gear ring two (24), planet wheel two (26) with gear two (22) meshing, be connected with bracing piece (28) on two (26) through connecting axle (27), the other end of bracing piece (28) is connected with main shaft (29) jointly, be equipped with drive gear three (30) on main shaft (29), the other end of drive gear (30) with output shaft (11).

3. The final drive device of a wheeled tractor according to claim 2, wherein the heat dissipation port sealing mechanism (15) comprises an arc-shaped sealing plate (31), two ends of the arc-shaped sealing plate (31) are respectively provided with a first connecting side plate (32) and a second connecting side plate (33), the first connecting side plate (32) is provided with a first guide hole (34), a first guide post (35) connected with the inner wall of the extension shell (5) is arranged in the first guide hole (34) in a penetrating manner, and a first positioning spring (36) is sleeved outside the first guide post (35).

4. A wheel tractor final drive device according to claim 3, characterized in that the self-driven opening and closing mechanism (14) comprises an outer cylinder body (38) arranged on the heat absorbing plate (37), a piston (39) is arranged in the outer cylinder body (38), the outer cylinder body (38) is divided into a gasification bin (40) and a movable bin (41) by the piston (39), gasification liquid is arranged in the gasification bin (40), limit baffles (42) are symmetrically arranged in the gasification bin (40), a second guide column (43) movably penetrating through the outer cylinder body (38) is arranged at the other end of the piston (39), the second guide column (43) is connected with the second connecting side plate (33), and a second positioning spring (44) is arranged at one end of the second guide column (43) positioned in the movable bin (41).

5. A final drive for a wheeled tractor as claimed in claim 4, wherein said stable support structure (12) comprises an outer mounting ring (45), an inner movable ring (46) being provided in said outer mounting ring (45), and an antifriction layer (47) being provided in said inner movable ring (46).

6. The final drive device for a wheeled tractor according to claim 5, wherein a guiding circular groove (48) is formed in the inner wall of the outer mounting ring (45), a plurality of guiding balls (50) are uniformly arranged in the guiding circular groove (48), the guiding balls (50) are connected with the outer wall of the inner movable ring (46) through connecting blocks (49), and auxiliary diagonal rods (51) connected with the outer wall of the inner movable ring (46) are arranged on two sides of the connecting blocks (49) of the guiding balls (50).

7. The final drive device for a wheeled tractor according to claim 6, wherein the first gear ring (16) and the second gear ring (24) are provided with lubrication cavities (52), the lubrication cavities (52) are provided with support columns (53), the inner bottoms of the lubrication cavities (52) are provided with four lubrication ports (54), and one ends of the lubrication ports (54) located in the lubrication cavities (52) are provided with moisture absorption sponges (55).