JP2010060069A - Traveling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a traveling device supplying sufficient amount of lubricating oil to a sun gear. <P>SOLUTION: The traveling device is provided with a cylindrical axle housing 25 fixed to a vehicle body; a rotating shaft 12 extended axially within the axle housing 25 and driven by an electric motor 6; a rim 11 rotatably provided on the outer peripheral side of the axle housing 25 via a bearing and mounted with a wheel 5; and planetary gear deceleration mechanisms 7, 17 provided between the rim 11 and the axle housing 25 and decelerating and transmitting the rotation of the rotating shaft 12 to the rim 11. The planetary gear deceleration mechanisms 7, 17 comprise the sun gears 13, 18, ring gears, a plurality of planetary gears and carriers 26, 27. At least one of carriers 26, 27 is provided above the center of the rotating shaft 12, and the carriers 26, 27 have oil passage 28, 29 for making lubricating oil drop down to the sun gears 13, 18. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is provided in a wheeled vehicle such as a dump truck that transports crushed stone mined in a mine or the like, for example, and includes a travel motor and a planetary gear speed reduction mechanism that decelerates the rotation of the travel motor rotation shaft and transmits it to the wheels. The present invention relates to a traveling device having the same.

  Generally, a traveling device that travels and drives a wheel-type vehicle, for example, a driving wheel of a dump truck, is provided with a cylindrical axle housing that is attached to a vehicle body and an axially extending inside the axle housing. A rotation shaft that is driven to rotate by a power source, a rim that is rotatably provided on the outer periphery of the front end side of the axle housing via a bearing, and is provided between the rim and the axle housing, and a rotation of the rotation shaft. And a multi-stage planetary gear speed reduction mechanism that transmits the speed to the rim.

  The planetary gear speed reduction mechanism generates rotational torque on driving wheels such as front wheels or rear wheels of the vehicle by decelerating the rotational output of a driving source composed of, for example, an electric motor and transmitting it to a rim (wheel). Is to run.

  In the prior art described above, the planetary gear reduction mechanism for increasing the rotational torque of the vehicle is constituted by a sun gear, a plurality of planetary gears, a ring gear, a carrier, and the like. The carrier is fixed to the axle housing in a non-rotatable manner, and supports a plurality of planetary gears that rotate in accordance with the rotation of the sun gear, via a plurality of support pins, and transmits the rotation of each planetary gear to the ring gear. Thus, it is configured to take out to the outside as rotation output.

By setting it as such a structure, a carrier can support a planetary gear in the state fixed to the axle housing so that rotation was impossible, and can comprise a planetary gear reduction mechanism. The carrier has sufficient rigidity to support a plurality of planetary gears so as to be rotatable, and can be formed into a sturdy structure, and the carrier is provided with a strength reinforcing member for a non-rotating portion (for example, an axle housing) of the traveling device. As a result, the strength and rigidity of the entire apparatus can be increased. In addition, this can reduce the thickness of the axle housing and reduce the weight. By fixing the carrier to the axle housing in a non-rotatable manner as described above, sufficient rigidity can be ensured and the strength and reliability of the entire traveling device can be improved (for example, see Patent Document 1).
JP 2007-2919 A

  In the above-described prior art, the carrier used for such a planetary gear speed reduction mechanism is fixed to the axle housing in a non-rotatable manner, resulting in the following problems.

  That is, in such a dump truck traveling device, a large rotational load acts, so that lubricating oil is supplied to the bearing and planetary gear reduction mechanism provided between the axle housing and the rim, and these can be kept in a lubricated state. Necessary.

  In this case, if a large amount of lubricating oil is accommodated in the traveling device, energy loss or heat generation due to the stirring resistance of the lubricating oil occurs with the rotation of each gear. For this reason, the lubricating oil accommodated in the apparatus is generally set to a necessary minimum amount of oil (for example, about 1/5 to 1/3 of the internal volume). In this case, the oil level is located below the motor rotation shaft, and only the ring gear and the planetary gear are immersed in the lubricating oil.

  For this reason, in the prior art, the lubricating oil is stored at the lower position, and the lubricating oil sucked from the circulation pipe using a lubricating oil pump or the like is forcibly discharged to the outside of the device inside the rim. Thus, it is known to lubricate the bearings and planetary gears that constitute the planetary gear speed reduction mechanism by circulating the lubricating oil accumulated inside and circulating the lubricant oil before and after the carrier.

  Thereby, the lubricating oil supplied to the planetary gear reduction mechanism is scattered as oil droplets with the rotation of the planetary gear, or is transmitted to the sun gear engaged through the tooth surface of the planetary gear, The gear is lubricated. However, depending on the traveling state of the vehicle, for example, when traveling on an uphill road, the suction of the lubricating oil by the lubricating oil pump becomes insufficient, and a sufficient amount of lubricating oil may not be supplied to the sun gear. In addition, if some foreign matter enters the lubricating oil circulation path, the circulation pipe may be clogged and the lubricating oil may not be circulated. Furthermore, since the carrier must support the high rotational load of the planetary gear, some carriers have a strut for reinforcing strength in a space other than the space where the planetary gear is accommodated. The sun gear that is located is behind the column, and the arrival of the oil droplets scattered by the rotation of the planetary gear is hindered. In these cases, the durability and life of the traveling device provided with the planetary gear speed reduction mechanism are reduced.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a traveling device capable of supplying a sufficient amount of lubricating oil to the sun gear.

  In order to achieve this object, in the traveling device according to the present invention, a cylindrical axle housing that is fixed to the vehicle body, and a rotation that is provided extending in the axial direction in the axle housing and is rotationally driven by a drive source. A shaft, a rim that is rotatably provided on the outer peripheral side of the axle housing via a bearing, and is provided between the rim and the axle housing, and a rim on which a wheel is attached, and the rotation of the rotating shaft is decelerated to the rim. The planetary gear speed reduction mechanism is configured by a sun gear, a ring gear, a plurality of planetary gears, and a carrier that holds the planetary gear and is non-rotatably fixed to the axle housing. In the traveling device, at least one carrier is provided above the center of the rotating shaft, and is an oil that drops lubricating oil on the sun gear. It is characterized by having a.

  In the present invention configured as described above, the lubricating oil splashed up by the rotation of the planetary gear is attached to the axle housing and the ring gear, and then is provided on the carrier when falling again as an oil droplet. By dripping the sun gear through the oil passage, a sufficient amount of lubricating oil can be supplied to the sun gear.

  Moreover, the traveling device according to the present invention is characterized in that, in the above-described invention, the dripping side opening of the oil passage is disposed immediately above the sun gear. In the present invention configured as described above, the lubricating oil dropped from the dropping side opening of the oil passage can surely reach the sun gear.

  Moreover, the traveling device according to the present invention is characterized in that, in the above invention, the oil passage is constituted by a long hole penetrating the inside of the carrier. The present invention configured as described above can drop the lubricating oil onto the sun gear without being affected by the inclination of the vehicle as compared with the case where the oil passage is configured by a groove.

  Moreover, the traveling device according to the present invention is characterized in that, in the above-described invention, an oil sump having a concave surface larger than the diameter of the oil passage is provided in the inlet side opening of the oil passage. The present invention configured as described above can efficiently collect the lubricating oil falling on the carrier after being attached to the axle housing or the ring gear as oil droplets again.

  Moreover, the traveling device according to the present invention is characterized in that, in the above-described invention, a guide means is extended to a dripping side opening of the oil passage. In the present invention configured as described above, the lubricating oil can be guided to a position close to the sun gear by the guide means even when the dropping side opening cannot be provided directly above the sun gear.

  According to the present invention, an oil passage is provided on a carrier fixed to a vehicle body that is fixed to a vehicle body so as not to rotate. Therefore, when the lubricating oil bounced up by the rotation of the planetary gear adheres to the axle housing or the ring gear and then drops again as oil droplets, it is applied to the sun gear via the oil passage provided in the carrier. By dripping, a sufficient amount of lubricating oil can be supplied to the sun gear. Thereby, fresh lubricating oil can be continuously supplied to a sun gear, and durability and lifetime of a traveling apparatus can be improved compared with the past.

  Hereinafter, the best mode for carrying out a traveling device according to the present invention will be described with reference to the drawings.

  FIG. 1 is a side view of a mine dump truck provided with an embodiment of a traveling device according to the present invention, and FIG. 2 is a rear view of the dump truck shown in FIG.

  A wheel-type vehicle, for example, a mine dump truck, provided with an embodiment of a traveling device according to the present invention is mounted on a chassis 1 having a frame structure and can be raised and lowered on the chassis 1 as shown in FIGS. A vessel 2 as a cargo bed, a cabin 3 disposed on the front side of the chassis 1, and a plurality of wheels 5. As shown in FIG. 2, the traveling device 4 according to the present embodiment is disposed at the rear portion of the chassis 1 and rotationally drives the rear wheels of the wheels 5.

  FIG. 3 is a cross-sectional view of an essential part showing an embodiment of the traveling apparatus according to the present invention. FIG. 4 is a cross-sectional view of a main part of the first carrier 26 shown in FIG. FIG. 5 is a cross-sectional view of a main part of the second carrier 27 shown in FIG.

  As shown in FIG. 3, the traveling device 4 according to the present embodiment includes an electric motor 6 that is a drive source, and a cylindrical spindle 8 that fixes the electric motor 6 to the chassis 1 shown in FIGS. ing. Further, the traveling device 4 is fixed to the wheel 10 to which the rotation of the electric motor 6 is finally transmitted via two planetary gear reduction mechanisms 7 and 17 to be described later, and the wheel 5 described above is fixed. A rim 11 is provided that is integrally attached. Further, the traveling device 4 includes an axle housing 25 formed in a cylindrical shape that supports the wheel 10 and is connected to the spindle 8 to be fixed to the chassis 1.

  Of the two planetary gear reduction mechanisms 7 and 17 provided in the present embodiment, the first planetary gear reduction mechanism 7 includes a sun gear 13 integrally engaged with the rotating shaft 12 of the electric motor 6, and the sun gear 13. A plurality of planetary gears 14 that engage and rotate with each other, a ring gear 15 that engages and rotates with these planetary gears 14, and a first carrier 26 that supports the planetary gear 14. The first carrier 26 is fixed to the axle housing 25. The first carrier 26 includes a support pin 22 that rotatably supports the plurality of planetary gears 14 via the bearing 20. The ring gear 15 includes a gear coupling 16 that is integrally fixed, and a sun gear 18 that is integrally engaged with the tip of the gear coupling 16.

  The second planetary gear reduction mechanism 17 includes the aforementioned sun gear 18, a plurality of planet gears 19 that engage and rotate with the sun gear 18, a ring gear 24 that engages and rotates with these planet gears 19, and a planet gear. And a second carrier 27 that supports 19. Similar to the first carrier 26, the second carrier 27 is also fixed to the axle housing 25. The second carrier 27 includes a support pin 23 that rotatably supports the plurality of planetary gears 19 via bearings 21.

  Here, since both the first carrier 26 and the second carrier 27 must support a high rotational load of the planetary gears 14 and 19, in the present embodiment, as shown in FIGS. The carrier 26 and the second carrier 27 are provided with struts 35 and 36 for reinforcing strength in a space other than the space where the planetary gears 14 and 19 are accommodated.

  In the present embodiment, at least one of the first carrier 26 and the second carrier 27 is provided above the center of the rotating shaft 12, and the oil passages 28 and 29 for dropping the lubricating oil 33 to the sun gears 13 and 18. Have For example, as shown in FIG. 4, an oil passage 28 having a dripping side opening is provided directly above the sun gear 13 with respect to the support 35 positioned above the center of the rotation shaft 12 in the first carrier 26. The oil passage 28 is composed of a long hole penetrating the inside of the support 35 that is vertically formed toward the sun gear 13. The oil passage 28 also includes a concave oil sump 30 larger than the diameter of the oil passage 28 at the inlet side opening.

  Further, in the present embodiment, as shown in FIG. 5, the oil path 29 is provided for the two support columns 36 positioned above the rotation shaft 12 in the second carrier 27. The oil passage 29 is formed of a long hole penetrating the inside of the support column 36 toward the sun gear 13. Further, the oil passage 29 is provided with, for example, a nozzle 32 for guiding the lubricating oil 33 to the dropping side opening. The oil passage 29 includes a concave oil sump 31 larger than the diameter of the oil passage 29 at the opening on the inlet side.

  Further, in the present embodiment, as shown in FIG. 3, the planetary gear 14 constituting the first planetary gear reduction mechanism 7 has an oil level that allows the lower half of the gear located below the rotary shaft 12 to be immersed. An amount of lubricating oil 33 is contained. This is because the minimum amount is set in order to increase the stirring resistance caused by the lubricating oil 33 as the planetary gear rotates, and to reduce the heat generation of the lubricating oil 33 accompanying the stirring. A circulation pipe 34 is connected to the accommodation space for the lubricating oil 33.

  In the present embodiment configured as described above, the rotation of the electric motor 6 is transmitted to the sun gear 13 via the rotating shaft 12, and the sun gear 13 includes a plurality of planetary gears 14 constituting the first planetary gear reduction mechanism 7. Rotate. The first carrier 26 rotatably supports the three planetary gears 14 by the support pins 22 and is engaged with the sun gear 13. Since the first carrier 26 itself is fixed to the axle housing 25 so as not to rotate, and the planetary gears 14 are supported by the support pins 22 fixed to the first carrier 26, these planetary gears 14 are allowed to rotate only. , Have been restrained to revolve. For this reason, the planetary gear 14 rotates the ring gear 15 only by rotation.

  The ring gear 15 rotates the sun gear 18 integrally engaged with the tip end portion of the gear coupling 16 around the same axis center as the rotation shaft 12 through a gear coupling 16 fixed integrally. Let The second carrier 27 rotatably supports the three planetary gears 19 by the support pins 23 and is engaged with the sun gear 18. The second carrier 27 itself is fixed to the axle housing 25 so as not to rotate, and the planetary gears 19 are supported by the support pins 23 fixed to the second carrier 27. Therefore, the planetary gears 19 are allowed to rotate only. , Have been restrained to revolve. For this reason, the planetary gear 19 rotates the ring gear 24 only by rotation. When the wheel 10 integrally engaged with the ring gear 24 rotates, the wheel 5 engaged with the rim 11 rotates. As described above, the rotation of the electric motor 6 is decelerated by the planetary gear speed reduction mechanisms 7 and 17 while increasing the torque, and the dump truck travels due to the rotation of the wheel 5 having obtained a large torque.

  Here, in the present embodiment, as described above, of the planetary gears 14 constituting the first planetary gear reduction mechanism 7, the oil level is such that the lower half of the gears located below the center of the rotary shaft 12 is immersed. The amount of lubricating oil 33 is stored. The lubricating oil 33 circulates through a gap formed between the planetary gear 14 and the ring gear 15 between the axle housing 25 and also lubricates the planetary gear 19 that constitutes the second planetary gear reduction mechanism 17. Further, the lubricating oil 33 flows from the second planetary gear reduction mechanism 17 to the bottom of the space between the wheel 10 and the axle housing 25 and is accommodated.

  Further, the gears and bearings constituting the traveling device 4 according to the present embodiment need to be kept in a lubrication state because they receive a large rotational load, and are accommodated in a space bottom formed by the axle housing 25 and the wheel 10. The lubricating oil 33 is forcibly circulated by a circulation pump (not shown) through the circulation pipe 34 and supplied to the planetary gears and the bearings constituting the traveling device 4.

  Since the first carrier 26 and the second carrier 27 respectively support the planetary gears 14 and 19 so as to be rotatable with respect to rotation, the lubrication accommodated in the bottom of the axle housing 25 among the plurality of planetary gears 14 and 19. The gear immersed in the oil 33 springs up the lubricating oil 33 in the form of oil droplets in the circumferential direction as it rotates. Also, the lubricating oil 33 is supplied to the gears of the planetary gears 14 and 19 that are not immersed in the lubricating oil 33 by forced circulation, so that the lubricating oil 33 is scattered by the rotation of the planetary gears 14 and 19.

  The oil droplets of the lubricating oil 33 bounced up by the planetary gears 14 of the first planetary gear speed reduction mechanism 7 adhere to the ring gear 15 and the axle housing 25 and then fall again as oil droplets, whereby the axle housing 25 Is housed in the bottom. In addition, the oil droplets of the lubricating oil 33 bounced up by the planetary gears 19 of the second planetary gear reduction mechanism 17 also adhere to the ring gear 24 and then fall again as oil droplets, so that the second carrier 27 It is accommodated from the bottom to the bottom of the space between the wheel 10 and the axle housing 25.

  Here, in the present embodiment, as shown in FIG. 4, the support 35 that is positioned above the rotating shaft 12 in the first carrier 26 is positioned directly above the sun gear 13, so that the oil path 28 is The dripping side opening is arranged directly above the sun gear 13. For this reason, the lubricating oil 33 that has been splashed once and dropped onto the support column 35 is collected by the concave oil reservoir 30 that is larger than the diameter of the oil passage 28, passes through the oil passage 28, and opens on the dropping side. It is dripped with respect to the sun gear 13 just under from a part. The dripping lubricating oil 33 lubricates the tooth surfaces of the sun gear 13, a part of which is spun up again by the rotation of these gears and then falls again, and a part of the bottom of the axle housing 25 directly. And is collected at the bottom of the space between the wheel 10 and the axle housing 25.

  On the other hand, in the second carrier 27, as shown in FIG. 5, since the support column 36 is not directly above the sun gear 18, the two support columns 36 are positioned above the center of the rotating shaft 12. The lubricating oil 33 that has been splashed once and then dropped onto the pillars 36 is collected by a concave oil sump 31 that is larger than the diameter of the oil passages 29, and passes through the oil passages 29 formed in these pillars 36. Then, it is dripped with respect to the sun gear 18 from the nozzle 32 provided extending in the dropping side opening. The dripping lubricating oil 33 lubricates the tooth surfaces of the sun gear 18, a part of which is spun up again by the rotation of these gears and then falls again, and a part thereof directly on the bottom of the axle housing 25. It falls down and is collected at the bottom of the space between the wheel 10 and the axle housing 25.

  According to the present embodiment configured as described above, even if the forced circulation of the lubricating oil 33 through the circulation pipe 34 becomes insufficient, the oil passages 28 and 29 are sufficient for the sun gears 13 and 18. The lubricating oil 33 can be supplied, and the sun gears 13 and 18 can be lubricated. In addition, since the fresh lubricating oil 33 can be continuously supplied to the sun gears 13 and 18, the durability and life of the traveling device 4 can be improved.

  In addition, since the oil passage 28 provided in the first carrier 26 has the dripping side opening disposed directly above the sun gear 13, the lubricating oil 33 can be reliably dripped onto the sun gear 13.

  The oil passages 28 and 29 can also be constituted by grooves provided on the carrier surface. For example, when the dump truck is in an inclined posture during climbing, the oil passage is also inclined. There is also a risk of spilling out before being dropped on 13,18. As in the present embodiment, by constituting the long holes penetrating the oil passages 28 and 29, the lubricating oil 33 can be stably dropped onto the sun gears 13 and 18 even in the inclined posture.

  Further, concave oil reservoirs 30 and 31 for guiding the lubricating oil 33 to the oil passages 28 and 29 are formed on the support columns 35 and 36, and the lubricating oil 33 that has fallen by the oil reservoirs 30 and 31 is received. It can be recovered efficiently and more lubricating oil 33 can be guided to the oil passages 28 and 29 and dropped onto the sun gears 13 and 18.

  However, since the oil passage 29 does not have a dripping side opening directly above the sun gear 18, the dripped lubricating oil 33 may not be dripped onto the sun gear 18. In the present embodiment, a nozzle 32 serving as a guide means is extended to the dropping side opening of the oil passage 29, and the lubricating oil 33 can be reliably dropped onto the sun gear 18 by the nozzle 32.

  In the present embodiment, for example, the first carrier 26 is manufactured by casting. Therefore, by devising the mold shape, the oil passage 28 and the oil sump 30 can be configured on the support 35 of the first carrier 26 at the casting stage, and the support 35 is cut to form the oil passage 28 and the oil sump 30. There is no need for post-processing. Thereby, member production costs can be reduced.

  Similarly, for the second carrier 27, the oil passage 29 and the oil reservoir 31 can be configured on the support 36 of the second carrier 27 at the casting stage. In this case, when it is difficult to form the oil passage 29 having different directions in each of the two struts 36 at the casting stage due to the production of the mold, the oil passage 29 and the oil reservoir 31 are provided only on one of the struts. Although it may be formed, it is desirable to form an oil passage and an oil reservoir to both struts in which a larger amount of the lubricating oil 33 can be secured.

  In the present embodiment, the oil passages 28 and 29 are formed by forming long holes that penetrate the support posts 35 and 36 of the first carrier 26 and the second carrier 27. It may be provided separately. In this case, the degree of freedom in arrangement can be increased as compared to providing a long hole penetrating the support.

  Further, in the present embodiment, the oil reservoirs 30 and 31 are formed on the support posts 35 and 36 of the first carrier 26 and the second carrier 27. However, members constituting the oil reservoir may be separately provided and arranged. . In this case, it is possible to arrange an oil reservoir having a larger area than to provide an oil reservoir in the support column itself, and to improve the recovery efficiency of the lubricating oil 33.

  Moreover, in this embodiment, although the oil path provided in each support | pillar on a carrier is one, this invention is not restricted to this, You may provide multiple oil paths in the support | pillar on each carrier. In this case, it is desirable that the plurality of oil passages be arranged side by side along the axial direction of the sun gear.

  Further, in this embodiment, the planetary gear reduction mechanism is configured in two stages, and an oil passage is formed for any planetary gear reduction mechanism, but the present invention is not limited to this, and either one of the planetary gear reduction mechanisms is formed. An oil passage may be provided only for the planetary gear reduction mechanism. Furthermore, the planetary gear speed reduction mechanism is not limited to the two-stage configuration in the present embodiment, and may have a multi-stage configuration of three or more stages. However, from the viewpoint of ensuring lubricity, it is desirable to implement the present invention for all planetary gear reduction mechanisms.

  In this embodiment, since the electric motor 6 that rotates at a high speed is used as the drive source of the wheels 5, the planetary gear reduction mechanism is configured in two stages in order to increase the reduction ratio. The invention is not limited to this. For example, when a hydraulic motor is used as a drive source, the traveling device may be configured with one planetary gear reduction mechanism. In this case, the carrier to be an object of the present invention may be one stage.

It is a side view which shows the dump truck with which one Embodiment of the traveling apparatus which concerns on this invention is provided. FIG. 2 is a front view of the dump truck shown in FIG. It is principal part sectional drawing which shows one Embodiment of the traveling apparatus which concerns on this invention. It is principal part sectional drawing of the 1st carrier with which this embodiment is equipped. It is principal part sectional drawing of the 2nd carrier with which this embodiment is equipped.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Chassis 4 Traveling device 5 Wheel 6 Electric motor 7 1st planetary gear reduction mechanism 8 Spindle 10 Wheel 11 Rim 12 Rotating shaft 13 Sun gear 14 Planetary gear 15 Ring gear 17 2nd planetary gear reduction mechanism 18 Sun gear 19 Planetary gear 24 Ring gear 25 Axle housing 26 First carrier 27 Second carrier 28, 29 Oil passage 30, 31 Oil reservoir 32 Nozzle 33 Lubricating oil 34 Circulation piping 35, 36 Carrier strut

Claims (5)

A cylindrical axle housing that is fixed to the vehicle body, a rotating shaft that extends in the axial direction inside the axle housing and is driven to rotate by a driving source, and is rotatable on the outer peripheral side of the axle housing via a bearing. A rim provided with a wheel and a planetary gear reduction mechanism provided between the rim and the axle housing and transmitting the rotation of the rotary shaft to the rim by reducing the rotation, and the planetary gear reduction mechanism, In a traveling device comprising a sun gear, a ring gear, a plurality of planetary gears, and a carrier fixed to an axle housing that holds the planetary gears,
The carrier is provided with at least one carrier that is provided above the center of the rotating shaft and has an oil passage for dripping lubricating oil to the sun gear.   The traveling device according to claim 1, wherein the oil passage has a dripping side opening disposed immediately above the sun gear.   3. The traveling device according to claim 1, wherein the oil passage includes a long hole penetrating the inside of the carrier.   The traveling device according to any one of claims 1 to 3, wherein the oil passage is provided with an oil sump having a concave surface larger than a diameter of the oil passage at an inlet side opening.   The traveling device according to any one of claims 1 to 4, wherein the oil passage has a guide means extending to a dripping side opening.

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