JP2011196478A - Driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving device capable of improving power transmission efficiency by reducing an agitation loss and capable of efficiently lubricating and cooling a brake device.SOLUTION: A driven gear 13 to be driven by external power, a shaft 17 transmitting output of the driven gear 13 to driving wheels and a movable pushing disk 31 of the brake device 30, which generates braking force, are housed in the driving device 10 covered with a case 19 and a cover 11 and filled with lubricating oil. The movable pushing disk 31 of the brake device 30 is provided freely to move forward/backward in a direction coming close to or separating from the cover 11, and a space between the cover 11 and the movable pushing disk 31 is formed as an oil reservoir part 42, into which the lubricating oil scraped up by the driven gear 13 enters. The movable pushing disk 31 is provided with a communication part passing through the direction, in which the movable pushing disk 31 moves forward/backward, to communicate both of a surface side and a back surface side of the movable pushing disk 31 with each other.

Description

  The present invention relates to a drive device, and more particularly to a drive device used for power transmission in an industrial vehicle such as a forklift.

Conventionally, it is known that a wet brake device is housed in a vehicle drive device (see, for example, Patent Document 1).
In such a drive device, the brake disc, particularly the brake disc, whose temperature rises is lubricated and cooled by the lubricating oil filled in the device. That is, the lubricating oil filled in the device stays at a predetermined oil level on the bottom side of the case constituting the driving device, and the brake disc on the driven gear side passes through this lubricating oil. Lubricating, cooling, or scattering the accumulated lubricating oil with a driven gear or the like, and lubricating and cooling the brake disk from the outer peripheral side with the scattered lubricating oil.

JP 2005-29117 A

However, in the technique described in Patent Document 1, the lubricating oil stays at a predetermined oil level or higher at the bottom side of the case at all times, and a large amount of the remaining lubricating oil is stirred by the driven gear or the brake disc integrated therewith. Therefore, there is a problem that the stirring loss is large and the power transmission efficiency is poor.
In particular, the lubricating oil that has been scraped up by the driven gear is scattered by the centrifugal force of the driven gear, so that there is a problem in that the lubricating oil and the cooling capacity are not reliably supplied to the brake disk.

  An object of the present invention is to provide a drive device that can reduce stirring loss and improve power transmission efficiency, and can also efficiently lubricate and cool a brake device.

  The drive device of the present invention includes a gear driven by power from the outside, a shaft that transmits the power of the gear to a driven body, and a brake device that generates a braking force inside the case and the cover. A drive device in which a movable disk for pressing is housed and filled with lubricating oil, and the movable disk for pressing of the brake device is provided so as to be movable forward and backward in a direction approaching and separating from the cover, A space between the cover and the pressing movable disk is an oil storage part into which the lubricating oil scraped up by the gear enters, and penetrates the pressing movable disk in the advancing and retreating direction. It is characterized in that a communicating portion is provided for communicating both the front and back sides of the pressing movable disk.

  In the drive device according to the present invention, the oil reservoir is formed over the space.

  In the drive device according to the present invention, a diaphragm is formed around the oil reservoir by a gap between the inner wall of the cover and the outer periphery of the pressing movable disk.

  The drive device of the present invention includes a drive gear that meshes with the gear to transmit power from the outside to the gear, and the lubricating oil is placed on the drive gear side inside the case and the cover. A guide-side lubricating oil passage is provided.

According to the drive device of the present invention, since the space between the cover and the pressing movable disk is an oil storage portion, the lubricating oil scooped up by the gear is stored in the oil storage during the operation of the drive device. It is stored in the part. Therefore, the amount of lubricating oil stored in the oil storage portion can be significantly lower than the conventional level of the lubricating oil in the case, and the amount of lubricating oil agitated by the rotating gear, brake disc, etc. can be reduced, The power transmission efficiency can be improved by reducing the stirring loss.
In addition, the lubricating oil stored in the oil storage section flows out to the front side (opposite side of the cover) of the pressing movable disk through the communicating portion of the pressing movable disk, and the discharged lubricating oil is a gear or the like Is brought into contact with the outer periphery. Accordingly, since the lubricating oil is supplied from the inside to the brake disc or the like, it is possible to efficiently cool the necessary portion of the brake device by suppressing the scattering of the lubricating oil.

  In the drive device of the present invention, when the oil reservoir is formed over the top and bottom, the head pressure (hydraulic pressure) of the lubricant in the oil reservoir can be used effectively, and the required amount of lubricant can be smoothly flowed from the communicating portion. Can be drained into.

  In the drive device of the present invention, when the throttle is formed by a gap between the inner wall of the cover and the outer periphery of the pressing movable disk, there is a concern that the lubricating oil stored in the oil reservoir easily flows out through the gap. In addition, it is possible to reliably maintain the supply of the lubricating oil through the communication portion.

  In the driving device of the present invention, when a drive gear for transmitting power such as an electric motor to the gear is provided, and a gear side lubricating oil passage for guiding the lubricating oil to the drive gear side is provided inside the case and the cover In such a gear side lubricating oil passage, the lubricating oil after cooling the brake device passes, and the meshing portion on the drive gear side with such lubricating oil and the bearing that supports the drive gear Etc. can be lubricated well.

FIG. 3 is a vertical sectional view showing a driving apparatus according to an embodiment of the present invention. FIG. 3 is a horizontal sectional view showing the driving device. The figure which shows the cover used for the said drive device from inner side. The figure which shows the case used for the said drive device from an inner side.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 and 2, the drive device 10 of the present embodiment is a device for driving the drive wheels (driven body) of the electric forklift, and is composed of various metal members.

[Overall structure of drive unit]
Specifically, the drive device 10 has an electric motor (not shown) attached to the outside of the cover 11, a drive gear 12 that is spline-coupled to the output shaft of the electric motor, a driven gear 13 that is driven by the drive gear 12, and a driven gear. 13, an output gear 14 that rotates integrally with the output gear 13, a planet gear 15 that meshes with the output gear 14, a ring gear 16 that meshes with the planet gear 15, a shaft 17 that pivotally supports the planet gear 15 so as to rotate freely, and a hub attachment that is splined to the shaft 17 A member 18 is provided, and a hub portion of a tire wheel constituting a driving wheel is attached to the hub attachment member 18.

  Each of the members 12 to 17 and the hub mounting member 18 of the drive device 10 are housed in a case 19 covered with the cover 11. Here, the driven gear 13 is press-fitted into the step portion 22 of the rotating body 21, and the output gear 14 is integrally provided in advance on one end side of the rotating shaft of the rotating body 21. The end of the rotating body 21 on the output gear 14 side is pivotally supported by a bearing 23 fitted in the shaft 17, and the opposite end is pivotally supported by a bearing 24. The bearing 24 is fitted on the inner peripheral side of the annular holding member 25. As shown in FIG. 3, the holding member 25 is fixed to four mounting bosses 26 protruding from the inner surface of the cover 11 with bolts.

  A cylindrical disc mounting portion 27 that surrounds the outer peripheral side of the holding member 25 is provided on the step portion 22 of the rotating body 21 so as to protrude on the opposite side to the output gear 14. The brake disk 28 is attached so as not to rotate. At this time, the output gear 14, the rotating body 21, and the disk mounting portion 27 are integrally formed from the same base material by casting, forging, appropriate machining, or the like. Note that the output gear 14 and the rotating body 21 may be separate members and integrally connected by spline coupling, welding, bolting, press fitting, or the like. Further, the connection to the stepped portion 22 of the driven gear 13 is not limited to press-fitting, and the other connection methods described above can be employed.

  On the other hand, the ring gear 16 that meshes with the planet gear 15 is bolted to the inside of the case 19 through a fixing plate 16A (FIG. 2) at a plurality of locations in the circumferential direction. The shaft 17 is pivotally supported by a pair of bearings 29 together with the cylindrical portion of the hub mounting member 18 that is spline-coupled. These bearings 29 are fitted into the case 19 from the inner side and the outer side, respectively.

[Brake device]
The drive device 10 of the present embodiment is provided with a wet brake device 30 that sandwiches the brake disk 28 and generates a braking force on the drive wheels.
The brake device 30 is configured to generate a braking force by driving a substantially disc-shaped pressing movable disk 31 located in the cover 11 from the outside of the cover 11 by a hydraulic actuator 32. Is driven forward and backward in the direction of approaching and separating from the cover 11 along the axial direction (axial direction of the rotating shaft of the driven gear 13 and the like).

  More specifically, an annular pressing plate 33 is fixed to the end edge of the cover 11 on the opening side with bolts. The pressing plate 33 and the pressing movable disk 31 have opposing surfaces, and the brake disk 28 is located between these opposing surfaces. A plurality of other brake disks 34 attached to the inside of the cover 11 are interposed between the brake disks 28 and between the opposing surfaces and the brake disk 28. With the advancement of the pressing movable disk 31, the brake disks 28 and 34 are sandwiched between the opposing surfaces, and a braking force is generated.

  The pressing movable disk 31 is provided with four openings 35 through which the mounting bosses 26 protruding from the cover 11 pass, as indicated by a two-dot chain line in FIG. Of the four openings 35, the openings 35 </ b> A for the pair of mounting bosses 26 on the diagonal formed in a columnar shape are round holes. A sleeve 35C is inserted into the opening 35A, and the outer periphery of the mounting boss 26 is in sliding contact with the inner periphery of the sleeve 35C. That is, the pair of columnar mounting bosses 26 that are in sliding contact with the sleeve 35C function as guide posts when the pressing movable disk 31 advances and retreats.

  The hydraulic actuator 32 has a pressure oil chamber 36 into which oil flows in at the time of a brake operation, and a plunger 37 that advances by the oil that flows in. The movement of the plunger 37 is transferred to the pressing movable disk 31 via a power transmission member 38. It is the structure which advances the movable disk 31 for a press by transmitting. On the other hand, a coil spring 39 is interposed between the pressing movable disk 31 and the holding member 25 for holding the bearing 24, and the pressing movable disk 31 is released by the spring force of the coil spring 39 by releasing the brake operation. The power transmission member 38 and the plunger 37 are retracted.

[Lubrication structure of brake device]
The brake device 30 is lubricated and oil-cooled with a lubricating oil filled in the drive device 10. When the driving wheel is in a stopped state, the lubricating oil staying on the bottom side of the case 19 is at the oil level L1 shown in FIG. When the driving wheel is driven, the lubricating oil is stirred and scattered mainly by the driven gear 13 to rotate, lubricates the surrounding rotating parts, and adheres to the front and back of the driven gear 13 to the upper side inside the driving device 10. It is scraped up to.

  At this time, the inner wall of the case 19 in this embodiment is close to the outer periphery and front side surface of the driven gear 13 with slight gaps CL1 and CL2, and the driven gear 13 is in the circumferential direction with the holding plate 33 and the ring gear 16. Since they face each other in close proximity, it is possible to prevent agitation of a larger amount of lubricating oil than necessary, and to reduce the agitation loss of the lubricating oil.

  In the vicinity of the outer periphery of the driven gear 13 back side (pressing plate 33 side), as shown in FIG. 1, there is provided an inclined surface 13A that comes closer to the pressing plate 33 toward the outer peripheral tip. On the other hand, a notch 33 </ b> A that connects the front and back is provided at the upper position of the pressing plate 33. For this reason, the lubricating oil scooped up along the back side of the driven gear 13 is driven to the outer peripheral side by centrifugal force, and then scattered along the inclined surface 13A toward the notch 33A and enters the notch 33A (see FIG. Arrow A in 1).

  On the other hand, in FIGS. 1 and 3, a bulging portion 41 bulging outwardly so as to be separated from the pressing movable disk 31 is provided in the cover 11 with a predetermined width across the top and bottom. A space between the bulging portion 41 and the pressing movable disk 31 serves as an oil storage portion 42 for storing the lubricating oil scraped up on the upper side. That is, of the lubricating oil that has been scraped up to the upper side through the back side of the driven gear 13, the lubricating oil that has entered the notch 33A flows into the oil reservoir 42 from the upper side of the bulging portion 41, and The oil reservoir 42 is filled.

  While the drive device 10 is being driven, the oil level in the oil reservoir 42 is maintained at L2, and the oil level on the bottom side of the case 19 is greatly lowered to L3 accordingly. This oil level L3 is lower than the oil level of the conventional lubricating oil that has always been retained in the case during operation, and the stirring loss in the rotation of the driven gear 13 and the brake disc 28 that rotates integrally therewith. Is small enough. Note that the lubricating oil scattered on the brake device 30 side does not accumulate only in the oil reservoir 42 but enters the entire gap between the back side of the pressing movable disk 31 and the inner wall of the cover 11.

  On the other hand, of the mounting bosses 26 provided on the cover 11, the pair of mounting bosses 26 that do not function as guide posts are formed in a substantially fan-shaped irregular shape as shown in FIG. The opening 35 </ b> B on the pressing movable disk 31 side through which these mounting bosses 26 are inserted is also substantially fan-shaped and opens slightly larger than the mounting boss 26. Accordingly, a part of the opening 35 </ b> B penetrating along the advancing / retreating direction of the pressing movable disk 31 serves as a communication portion 43 that communicates the front and back of the pressing movable disk 31. A part of the communication portion 43 further directly connects the oil storage portion 42 and the front side of the pressing movable disc 31 (the side where the brake discs 28 and 34 are provided).

  Therefore, the lubricant accumulated in the oil reservoir 42 and the lubricant accumulated on the back side of the pressing movable disk 31 other than the oil reservoir 42 flow out to the front side of the pressing movable disk 31 through the communication portion 43. Then, by coming into contact with the rotating body 21 or the like, it is guided to the outer peripheral side by the centrifugal force, and is provided between the disk mounting portion 27 and the pressing movable disk 31 or along the radial direction at the disk mounting portion 27. The brake disks 28 and 34 are efficiently lubricated and cooled from the inner side through the plurality of holes 27A. At this time, the opening area of the opening 35 </ b> B is set such that a predetermined flow rate of lubricating oil flows out from the communicating portion 43, and the communicating portion 43 functions as a restrictor.

  Further, a gap CL3 is formed between the outer peripheral edge of the pressing movable disk 31 and the inner wall of the cover 11 except for an upper portion where the lubricating oil enters, and a diaphragm is formed by the gap CL3. Therefore, the throttle can increase the storage time of the lubricating oil in the oil storage portion 42, and can increase the heat radiation amount on the case 19 side. Lubricating oil required for lubrication and the like other than the brake disks 28 and 34 is supplied by being driven up by the driven gear 13 and supplied from the oil storage part 42 by bypassing the communication part 43.

  When the drive device 10 is in a stopped state, the lubricating oil in the oil storage part 42 flows downward from the communication part 43, and on the lower side of the cover 11, a press plate from a gap between the outer periphery of the pressing movable disk 31. It flows out to the case 19 side through another notch 33C of 33, and the oil level returns to L1.

  As shown in FIG. 2, the cover 11 and the pressing plate 33 are not in contact with each other at the position corresponding to the drive gear 12, and the concave portion 11 </ b> A (FIGS. 2 and 3) of the cover 11 and the pressing plate 33 Thus, a gear side lubricating oil passage 44 is formed. The gear side lubricating oil passage 44 is provided near the outer periphery of the driven gear 13 and just outside the brake discs 28 and 34, and the lubricating oil after cooling the brake discs 28 and 34 passes through the gear side lubricating oil passage 44. It is guided to the drive gear 12 side (arrow B in FIG. 2).

  In addition, the presser plate 33 is provided with a notch 33B that allows the front and back to communicate with each other at a position corresponding to the gear-side lubricating oil passage 44, so that the lubricating oil that is transmitted through the back side of the driven gear 13 is removed from the inclined surface 13A. It is supplied to the drive gear 12 side through 33B (arrow C in FIG. 2). With these lubricating oils, the bearing 45 for the drive gear 12 and the like are lubricated.

[Lubricating oil cooling structure]
In the case 19 shown in FIGS. 1, 2, and 4, a plurality of lubricant oils (eight in this embodiment) enter the opposite side to the pressing movable disk 31 of the brake device 30 sandwiching the driven gear 13. The oil reservoir chambers 51 are provided at appropriate intervals along the circumferential direction. Each oil reservoir small chamber 51 has a depth in a direction away from the driven gear 13 along the axial direction of the rotational axis of the driven gear 13, and the adjacent oil reservoir small chambers 51 are partitioned by reinforcing ribs 52.

  In other words, each oil reservoir chamber 51 has a structure in which a large annular oil reservoir chamber 50 is partitioned by eight reinforcing ribs 52. A part of the wall portion of the oil reservoir chamber 51 forms an outer peripheral portion 19 </ b> A having a predetermined thickness in the case 19. The outer surface of the outer peripheral portion 19 </ b> A is exposed to the outside air and is always at a low temperature by being located on the side of the brake device 30, particularly on the side opposite to the brake disks 28 and 34, with the driven gear 13 interposed therebetween.

  Such an oil reservoir chamber 51 has an opening 53 that opens toward the meshing portion of the planet gear 15 and the ring gear 16. Accordingly, the lubricating oil staying on the bottom side of the case 19 is scraped up by the planetary gear 15 by the self-revolving operation, and enters the oil reservoir 51. The lubricating oil that has entered the oil sump chamber 51 comes into contact with the wall portion of the oil sump chamber 51 including the reinforcing ribs 52 in a wide range, and the wall portion is also formed as the inner side of the outer peripheral portion 19A, so that the low temperature state is achieved. Therefore, it is cooled efficiently.

  In other words, the heat of the lubricating oil comes into contact with the low temperature portion of the case 19 away from the brake device 30 in a large area without providing the conventional heat receiving / radiating ribs and smoothly contacts the outer peripheral portion 19A of the case 19. Transmitted and cooled quickly. Further, another part of the wall portion of the oil reservoir chamber 51 forms an output shaft support wall 19B having a predetermined thickness in the case 19, and the shaft 17 is supported by using the output shaft support wall 19B. A mounting portion for the pair of bearings 29 is provided. Since no conventional heat receiving rib or the like is required, the inner side of the output shaft support wall 19B used for heat reception can be used as the mounting portion of the bearing 29.

  In addition, in the present embodiment, the lubricating oil scooped up on the front side surface (plane gear 15 side surface) of the driven gear 13 is supplied to the uppermost oil reservoir chamber 51A among the plurality of oil reservoir chambers 51. It is configured to actively escape.

  That is, as shown in FIGS. 1 and 4, the upper portion inside the case 19 is recessed toward the radially outer side and communicates with the oil reservoir chamber 51 </ b> A and the notch 33 </ b> A of the pressing plate 33. The cut space 54 is provided with a predetermined width along the axial direction. At the center position in the circumferential direction in the oil draining space 54, an oil draining portion 55 is provided that hangs down from the outer ceiling portion toward the inner side. The reason why the oil draining portion 55 is in the center of the oil draining space 54 is that both forward and reverse rotations of the driven gear 13 are considered.

  The oil draining portion 55 is positioned corresponding to the vicinity of the uppermost portion of the outer periphery of the driven gear 13, one end of which reaches the opening 53 of the oil sump chamber 51 </ b> A, and the other end is a tooth side surface of the driven gear 13 (on the meshing surface). Close to the tooth tip. Therefore, the meshing portion of the drive gear 12 and the driven gear 13 does not exist in the uppermost portion of the driven gear 13, but is set at a position shifted from the uppermost portion to one side in the rotational direction. They are meshed at a position shifted by about 90 ° from the upper part.

  The lubricating oil scraped up to the tooth tip side along the front side surface of the driven gear 13 is scraped off at the other end side of the adjacent oil draining portion 55 and guided to one end side in the axial direction of the rotating shaft (see FIG. Arrow D in 1). The lubricating oil guided to the one end side enters the oil reservoir small chamber 51A from the opening 53 and is cooled therein. Therefore, by providing the oil draining portion 55, the lubricating oil scooped up on the front side of the driven gear 13 is surely released in the axial direction at a position corresponding to the oil reservoir chamber 51A, not at the meshing position with the drive gear 12. Is possible.

  Further, the lubricating oil scraped up between the teeth of the driven gear 13 and the lubricating oil scraped up so as to cover the tooth tip between the gap 11 and the case 11 reached the oil draining space 54. At this point, it tries to scatter further outward, but it is scraped off at the portion facing the tooth tip of the oil draining portion 55 and guided in the axial direction along the ceiling portion in the oil draining space 54, and the oil reservoir chamber It is supplied to the 51A side or supplied to the notch 33A side of the pressing plate 33.

  Here, on the bottom side of the oil reservoir small chamber 51A, a shaft-side lubricating oil passage 56 made of a drill hole (drill hole) is provided downward. The shaft-side lubricating oil path 56 communicates with the pair of bearings 29 to lubricate the bearings 29 and reaches the spline coupling portion between the shaft 17 and the hub mounting member 18 to lubricate the coupling portion.

  The lubricating oil that has entered the oil reservoir chambers 51 is cooled in the oil reservoir chamber 51 and flows out of the opening 53 except for the oil that flows into the shaft-side lubricating oil passage 56 from the oil reservoir chamber 51A. It stays on the bottom side of the case 19.

  That is, in this embodiment, a part of the lubricating oil staying on the bottom side of the case 19 is scraped up on the back side of the driven gear 13 while the drive device 10 is operating, and enters the oil storage section 42. The brake discs 28 and 34 are lubricated and cooled, and the drive gear 12 is lubricated, while the other part is scraped up by the front side of the driven gear 13 and the planet gear 15 to lubricate and store oil in other locations. It is used for cooling in the small chamber 51.

Although the present embodiment has been described above, the present invention is not limited to the above-described embodiment, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention. Is.
For example, in the above-described embodiment, the communication portion 43 is formed using the opening 35 for penetrating the mounting boss 26 provided in the pressing movable disk 31, but the sleeve 35 </ b> C is attached to all such openings 35. The mounting boss 26 may be slid and contacted, and a communication portion may be provided separately from the opening 35, and a communication portion 43 using the opening 35 and a communication portion different from the opening 35 may be provided. Also good.

  INDUSTRIAL APPLICABILITY The present invention can be used not only for a drive device that drives the drive wheels of an electric forklift, but also for other industrial vehicle drive devices that incorporate a movable disk for pressing a brake device.

  DESCRIPTION OF SYMBOLS 10 ... Drive apparatus, 11 ... Cover, 12 ... Drive gear, 13 ... Driven gear which is a gear, 17 ... Shaft, 19 ... Case, 30 ... Brake device, 31 ... Movable disk for pressing, 42 ... Oil storage part, 43 ... Communication 44, a gear-side lubricating oil passage.

Claims (4)

Housed inside the case and cover are a gear driven by external power, a shaft that transmits the power of the gear to the driven body, and a pressing movable disk for the brake device that generates a braking force. And a drive device filled with lubricating oil,
The pressing movable disk of the brake device is provided so as to be able to advance and retreat in a direction approaching and separating from the cover,
The space between the cover and the movable disk for pressing is an oil storage portion into which the lubricating oil scraped up by the gear enters.
The driving device according to claim 1, wherein the pressing movable disk is provided with a communicating portion that penetrates in the advancing and retreating direction and communicates both the front and back sides of the pressing movable disk. The drive device according to claim 1,
The oil storage unit is formed over the space. The drive device according to claim 1 or 2,
Around the oil reservoir, a throttle is formed by a gap between the inner wall of the cover and the outer periphery of the pressing movable disk. The drive device according to any one of claims 1 to 3,
A drive gear that transmits external power to the gear by meshing with the gear is provided, and a gear side lubricating oil passage that guides the lubricating oil to the drive gear side is provided inside the case and the cover. A drive device characterized by being provided.

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