JP2015113851A - Turning device of construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrict the movement of a sun gear along a motor shaft even when using a carrier with a both-end support structure.SOLUTION: A planetary gear reduction mechanism 25 includes: a sun gear 26 spline-coupled to a motor shaft 19 of a hydraulic motor 15; a plurality of planetary gears 27 meshed with the sun gear 25 and an internal gear 14B, the planetary gears 27 revolving around the sun gear 26 while rotating; gear support shafts 33 for rotatably supporting each of the planetary gears 27; and a carrier 28 both-end supporting both-end sides in the vertical direction, of each of the gear support shafts 33, in which any one of the gear support shafts 33 of the carrier 28 is provided with a thrust plate 37 restricting the movement of the sun gear 26 along the motor shaft 19 of the hydraulic motor 15. Thereby, even when the carrier 28 has a both-end support structure, the movement of the sun gear 26 along the motor shaft 19 can be restricted.

Description

  The present invention relates to a swivel device for a construction machine that is preferably used in a swivel construction machine such as a hydraulic excavator or a hydraulic crane.

  In general, a hydraulic excavator as a representative example of a construction machine includes a self-propelled lower traveling body, an upper revolving body that is turnably mounted on the lower traveling body via a swirling wheel, and a front of the upper revolving body. It is roughly constituted by a working device provided on the part side. And a turning device is provided between the lower traveling body and the upper turning body, and the upper turning body turns on the lower traveling body by operating this turning device.

  In this case, the swivel device for a hydraulic excavator is normally attached to an upper swing body that is pivotably mounted on a lower traveling body via a swirl wheel, and extends upward and downward, and an upper end side of the housing. A turning motor provided in the housing, a planetary gear reduction mechanism provided in the housing for reducing the rotation of the turning motor, and the rotation of the turning motor decelerated by the planetary gear reduction mechanism to output the turning wheel. And an output shaft for turning.

  The planetary gear speed reduction mechanism includes a sun gear splined to the motor shaft of the swing motor, a plurality of planetary gears meshing with the sun gear and the internal gear and revolving around the sun gear, It is comprised by the carrier which has the gear support shaft which supports each planetary gear rotatably (for example, refer patent document 1).

JP 2005-61579 A

  By the way, in patent document 1 mentioned above, the sun gear spline-coupled to the motor shaft will move upward along the spline. In this case, since the length of the meshing between the sun gear and the planetary gear is shortened, torque is transmitted in an area where the contact area between the sun gear and the planetary gear is small. As a result, the contact surface pressure between the sun gear and the planetary gear increases, and the life of the gear may be reduced.

  Therefore, in another prior art, when the gear support shaft for supporting the planetary gear is a cantilevered carrier supported only at the lower end side, a thrust plate having an outer diameter similar to the outer diameter of the carrier. Is fixed to the upper end side of the gear support shaft with a retaining ring or a bolt so as to cover the upper side of the sun gear, and the movement of the sun gear is regulated. However, as in Patent Document 1 described above, in a carrier having a dual-support structure in which the gear support shaft is supported at both the upper and lower ends, a thrust plate having an outer diameter similar to the outer diameter of the carrier is used. There is a problem that it is difficult to dispose the sun gear so as to cover it.

  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 regulate the movement of the sun gear along the motor shaft even when a carrier having a both-end support structure is used. An object of the present invention is to provide a swivel device for a construction machine.

  In order to solve the above-described problems, the present invention provides a cylindrical housing that is attached to an upper swinging body that is turnably mounted on a lower traveling body via a swirling wheel and that extends upward and downward, and an upper end side of the housing. A turning motor provided in the housing, a planetary gear reduction mechanism provided in the housing for reducing the rotation of the turning motor, and the rotation of the turning motor decelerated by the planetary gear reduction mechanism to output the turning wheel. The planetary gear speed reduction mechanism includes a sun gear spline-coupled to the motor shaft of the turning motor, and meshes with the sun gear and the internal gear so as to rotate around the sun gear. A plurality of planetary gears, and a carrier having a gear support shaft for rotatably supporting each planetary gear, and supporting both upper and lower ends of each gear support shaft. It is applied to the turning device for a construction machine that.

  A feature of the configuration adopted by the invention of claim 1 is that any one of the gear support shafts of the carrier is engaged with the sun gear, and the sun gear is a motor shaft of the swing motor. A thrust plate is provided for restricting movement along the axis.

  According to a second aspect of the present invention, the sun gear includes a gear portion that meshes with each of the planetary gears, and a circular protruding portion that protrudes upward from the gear portion, and the thrust plate includes the carrier A support shaft side engaging portion that engages with the gear support shaft, and a sun gear side engaging portion that engages with the protruding portion of the sun gear.

  According to a third aspect of the present invention, the sun gear side engaging portion of the thrust plate has a circular hole inserted into the projecting portion of the sun gear or a concave arc shape engaged from the outer peripheral side with the projecting portion of the sun gear. This is because a concave groove is formed.

  According to a fourth aspect of the present invention, the carrier includes an upper support plate and a lower support plate that support both end portions of the gear support shafts in a state where the planetary gears are sandwiched from the axial direction. The support shaft side engaging portion that is sandwiched between the upper support plate of the carrier and the planetary gear in a state of being engaged with the gear support shaft and extends in the horizontal direction toward the sun gear; and The sun gear side engaging portion that abuts on the upper surface of the gear portion of the sun gear while being engaged with the protruding portion and extends in the horizontal direction toward the gear support shaft, the support shaft side engaging portion, and the sun gear That is, it is formed in a stepped shape by a connecting portion that connects with the side engaging portion with a step in the upward and downward directions.

  According to a fifth aspect of the present invention, the swing motor has a motor housing in which a rotation source is housed, and a bearing housing portion for housing a bearing that supports the motor shaft is provided on a lower end side of the motor housing. A thrust plate contact portion projecting toward the sun gear is provided in the bearing housing portion, and a portion of the thrust plate that engages with the sun gear is the sun gear and the thrust plate contact portion. It is in the structure arrange | positioned between.

  According to the first aspect of the present invention, even when the upper and lower ends of the plurality of gear support shafts are attached to the carrier, the gap between any one of the plurality of gear support shafts and the sun gear. A thrust plate can be disposed on the surface. Thereby, even when a carrier having a both-end support structure is used, the thrust plate can restrict the movement of the sun gear along the motor shaft. As a result, the meshing state between the sun gear and the planetary gear can always be kept good, so that the life of the sun gear and the planetary gear can be improved, and the reliability and stability of the swivel device can be improved. .

  According to invention of Claim 2, the thrust plate is engaging with the protrusion part which protrudes upwards from the gear part of a sun gear, and the gear support shaft of a carrier. Thereby, the thrust plate can stably suppress the sun gear from above. Further, the carrier rotates at a speed reduced by a reduction ratio compared to the rotational speed of the sun gear, and the thrust plate rotates together with the carrier. As a result, since friction caused by sliding between the sun gear and the thrust plate can be reduced, the amount of sliding wear, loss torque, and heat generation between the sun gear and the thrust plate can be suppressed.

  According to the invention of claim 3, when the circular hole is formed in the sun gear side engaging portion of the thrust plate, the contact area between the sun gear and the thrust plate can be widened. Can be stably suppressed. On the other hand, when the concave groove is formed in the sun gear side engaging portion of the thrust plate, the thrust plate can be engaged with the protruding portion of the sun gear from the outer peripheral side. As a result, the thrust plate can be easily engaged with the sun gear, so that the workability of the assembly work can be improved.

  According to invention of Claim 4, the thrust plate is comprised by the step shape by the support shaft side engaging part, the sun gear side engaging part, and the connection part. Thus, even when there is a step between the upper surface of the planetary gear assembled to the carrier and the upper surface of the gear portion of the sun gear, the step can be absorbed by the connecting portion of the thrust plate. As a result, when the thrust plate is engaged with the gear support shaft and the sun gear, the thrust plate can be assembled to the gear support shaft and the sun gear without rattling. The movement can be stably regulated.

  According to the invention of claim 5, the thrust plate abuts against the thrust plate abutting portion provided on the lower end side of the motor housing when the carrier moves upward, so that a thrust load is generated on the motor shaft. Can be suppressed. Thereby, the burden concerning a turning motor can be reduced.

  Further, the rotation speed of the carrier rotates at a speed reduced by a reduction ratio compared to the rotation speed of the sun gear, and the thrust plate rotates together with the carrier. As a result, the friction caused by sliding can be reduced compared with the case where the sun gear directly contacts the thrust plate contact portion, so that the sliding wear amount, loss torque, and heat generation of the sun gear and the thrust plate contact portion are reduced. Can be suppressed.

1 is a front view showing a hydraulic excavator provided with a turning device according to a first embodiment of the present invention. It is sectional drawing which shows the turning apparatus by 1st Embodiment. FIG. 3 is an enlarged cross-sectional view of a main part showing an enlarged view of a motor shaft, a planetary gear reduction mechanism and the like in FIG. FIG. 4 is a cross-sectional view of the planetary gear speed reduction mechanism in FIG. 3 as viewed from the direction of arrows IV-IV. It is a partially broken perspective view which shows the state which attaches a thrust plate to a carrier. It is a perspective view which shows a thrust plate alone. It is sectional drawing similar to FIG. 4 which shows the turning apparatus by the 2nd Embodiment of this invention. It is a perspective view which shows the state which attaches a thrust plate to a carrier. It is a perspective view which shows a thrust plate alone. It is sectional drawing similar to FIG. 3 which shows the turning apparatus by the 3rd Embodiment of this invention. It is a perspective view which shows a thrust plate alone. It is sectional drawing similar to FIG. 4 which shows the turning apparatus by the 1st modification of this invention. It is a perspective view which shows a thrust plate alone. It is sectional drawing similar to FIG. 4 which shows the turning apparatus by the 2nd modification of this invention. It is a perspective view which shows a thrust plate alone.

  Hereinafter, an embodiment of a turning device for a construction machine according to the present invention will be described in detail with reference to the accompanying drawings, taking as an example a case where it is applied to a hydraulic excavator.

  First, FIG. 1 to FIG. 6 show a first embodiment of the present invention. Here, reference numeral 1 denotes a hydraulic excavator which is a typical example of a construction machine. The hydraulic excavator 1 includes a self-propelled crawler type lower traveling body 2 and an upper portion mounted on the lower traveling body 2 so as to be able to turn. The revolving body 3 is generally configured. A work device 4 is provided on the front side of the upper swing body 3 so as to be able to move up and down, and the work device 4 is used for excavation work and the like. Further, a turning wheel 5 described later is provided between the lower traveling body 2 and the upper turning body 3, and the upper turning body 3 is supported on the lower traveling body 2 via the turning wheel 5 so as to be turnable.

  Reference numeral 5 denotes a turning wheel provided between the lower traveling body 2 and the upper turning body 3, and the turning wheel 5 includes an inner ring 5A fixed on a support cylinder 2A of the lower traveling body 2 shown in FIG. The outer ring 5B is fixed to the lower surface side of the swing frame 3A that is the base of the upper swing body 3, and a plurality of steel balls 5C (only one is shown) provided between the inner ring 5A and the outer ring 5B. Yes. Further, an inner tooth 5D is formed over the entire circumference on the inner circumference side of the inner ring 5A. Then, the turning device 11 described later is operated and the outer ring 5B fixed to the turning frame 3A rotates around the inner wheel 5A, so that the upper turning body 3 performs a turning operation on the lower traveling body 2. Yes.

  Next, the turning device 11 according to the first embodiment will be described.

  Reference numeral 11 denotes a turning device for turning the upper turning body 3 supported on the lower traveling body 2 via the turning wheel 5. The turning device 11 includes a housing 12, a hydraulic motor 15 as a turning motor, and an output described later. The shaft 20 and the reduction gear 23 including the planetary gear speed reduction mechanisms 25 and 26 are generally configured.

  Reference numeral 12 denotes a cylindrical housing disposed on the upper and lower sides of the swing frame 3A of the upper swing body 3. The housing 12 includes a lower housing 13 attached to the upper surface side of the swing frame 3A, and the lower side. The upper housing 14 is attached to the upper end side of the housing 13 and extends upward and downward from the upper surface of the turning frame 3A.

  A large-diameter annular flange portion 13A is provided on the lower end side of the lower housing 13, and the flange portion 13A is fastened to the turning frame 3A using a bolt 13B. On the other hand, the upper housing 14 is fastened to the upper end side of the lower housing 13 using bolts 14A. Further, an internal gear 14 </ b> B extending upward and downward is formed on the inner peripheral side of the upper housing 14 over the entire periphery. A motor housing 16 described later is fastened to the upper end side of the upper housing 14 using bolts 16D.

  Reference numeral 15 denotes a hydraulic motor as a turning motor provided on the upper end side of the upper housing 14. The hydraulic motor 15 is composed of, for example, a swash plate type hydraulic motor, and is roughly constituted by a motor housing 16 and a motor shaft 19. The hydraulic motor 15 rotates the motor shaft 19 by supplying and discharging pressure oil from a hydraulic pump (not shown) mounted on the upper swing body 3 and driving a rotation source (not shown). The upper swing body 3 is swung on the lower traveling body 2.

  Reference numeral 16 denotes a cylindrical motor housing in which a rotation source (not shown) such as a cylinder is accommodated. The motor housing 16 constitutes an outer shell of the hydraulic motor 15. The lower end side of the motor housing 16 is provided with an annular flange portion 16A that protrudes radially outward, a bottom portion 16B that extends radially inward from the flange portion 16A, and an interior of the upper housing 14 from the bottom portion 16B. It is comprised by the bearing accommodating part 16C which protrudes toward.

  The flange portion 16A of the motor housing 16 is fastened to the upper end side of the upper housing 14 using bolts 16D. The bearing housing portion 16C includes a bearing support portion 16C1 for housing a bearing 17 that supports a motor shaft 19 described later, and a thrust plate abutting portion that protrudes from the bearing support portion 16C1 toward the sun gear 26 described later. It is formed in a cylindrical shape by 16C2. Further, the inner peripheral side of the bearing housing portion 16 </ b> C serves as a motor shaft insertion hole 16 </ b> C <b> 3 through which a motor shaft 19 described later is inserted through the bearing 17. An oil seal 18 is provided below the bearing 17 to seal between the bearing housing portion 16C and a motor shaft 19 described later.

  A lower end surface 16C4 of the thrust plate abutting portion 16C2 is formed in an annular shape that is flat in the horizontal direction, and faces a thrust plate 37 described later. When the carrier 28 of the upper planetary gear speed reduction mechanism 25 described later moves (displaces) upward, the lower end surface 16C4 of the thrust plate contact portion 16C2 contacts (slides) the thrust plate 37. It has a configuration.

  Reference numeral 19 denotes a motor shaft provided in the motor housing 16 so as to extend upward and downward. The lower end side of the motor shaft 19 protrudes downward through the motor shaft insertion hole 16C3 of the bearing housing portion 16C, and is connected to an upper planetary gear reduction mechanism 25 described later. Here, the lower end side of the motor shaft 19 is rotatably supported by a bearing 17 provided on the bearing support portion 16C1 of the bearing housing portion 16C, and the upper end side of the motor shaft 19 is a bearing (not shown) on the motor housing 16. ) Is supported rotatably.

  The intermediate portion of the motor shaft 19 in the axial direction is coupled to a rotation source (not shown) by, for example, spline coupling. On the other hand, a male spline portion 19A is formed at the lower end portion of the motor shaft 19 protruding from the bearing housing portion 16C, and this male spline portion 19A is splined to a female spline portion 26C formed on a sun gear 26 described later. ing. Thereby, the motor shaft 19 is rotationally driven by the rotation source in the motor housing 16, and is configured to transmit this rotational force to an upper planetary gear reduction mechanism 25 described later.

  Reference numeral 20 denotes an output shaft that outputs rotation of a hydraulic motor 15 decelerated by a speed reducer 23 described later. The output shaft 20 is rotatably supported in the lower housing 13 via an upper bearing 21 and a lower bearing 22. The upper housing 13 extends upward and downward. Here, a male spline portion 20A is formed on the upper end side of the output shaft 20, and the male spline portion 20A is splined to a carrier 24C of a lower planetary gear reduction mechanism 24 described later.

  On the other hand, a pinion 20B is integrally provided on the lower end side of the output shaft 20, and the pinion 20B protrudes downward from the lower end portion of the lower housing 13 to the inner teeth 5D provided on the inner ring 5A of the turning wheel 5. Meshed. That is, the output shaft 20 outputs the rotation of the hydraulic motor 15 that has been decelerated by two stages by planetary gear reduction mechanisms 25 and 24 described later.

  Next, the speed reducer 23 arranged below the hydraulic motor 15 will be described.

  Reference numeral 23 denotes a speed reducer disposed on the lower side of the hydraulic motor 15. The speed reducer 23 decelerates the rotation of the hydraulic motor 15 and outputs it to the output shaft 20. Here, the speed reducer 23 includes an upper planetary gear reduction mechanism 25 located at the uppermost stage and a lower planetary gear reduction mechanism 24 located at the second stage (next stage).

  Reference numeral 24 denotes a lower planetary gear reduction mechanism disposed on the lower side in the upper housing 14, and the planetary gear reduction mechanism 24 decelerates the rotation of an upper planetary gear reduction mechanism 25 described later and transmits it to the output shaft 20. To do. The planetary gear reduction mechanism 24 meshes with a sun gear 24A spline-coupled to a carrier 28 of an upper planetary gear reduction mechanism 25, which will be described later, and the sun gear 24A and the lower side of the internal gear 14B of the upper housing 14, A plurality of planetary gears 24B (only one is shown) that revolves while rotating around the gear 24A, and a carrier 24C that rotatably supports each planetary gear 24B. The carrier 24C of the planetary gear speed reduction mechanism 24 is configured to be spline-coupled to a male spline portion 20A provided on the upper end side of the output shaft 20.

  Next, the upper planetary gear reduction mechanism 25 will be described.

  Reference numeral 25 denotes an upper planetary gear reduction mechanism disposed on the upper side in the upper housing 14, and the planetary gear reduction mechanism 25 is disposed between the hydraulic motor 15 and the lower planetary gear reduction mechanism 24. The rotation of the (motor shaft 19) is reduced and transmitted to the lower planetary gear reduction mechanism 24. The planetary gear reduction mechanism 25 is roughly constituted by a sun gear 26, a planetary gear 27, and a carrier 28, which will be described later.

  Reference numeral 26 denotes a sun gear connected to the motor shaft 19 of the hydraulic motor 15. The sun gear 26 includes a gear portion 26A that meshes with a planetary gear 27, which will be described later, a circular protrusion portion 26B that protrudes upward from the upper surface 26A1 of the gear portion 26A, and a gear portion 26A and a protrusion portion 26B. A stepped cylindrical body is formed by a female spline portion 26C penetrating upward and downward (axial direction). The sun gear 26 is disposed on a later-described plate 35 in a later-described carrier 28. The female spline portion 26 </ b> C of the sun gear 26 is splined to a male spline portion 19 </ b> A formed on the lower end side of the motor shaft 19 of the hydraulic motor 15. Therefore, the sun gear 26 rotates integrally with the motor shaft 19.

  Reference numeral 27 denotes a plurality of planetary gears that mesh with the sun gear 26 and an internal gear 14 </ b> B provided in the upper housing 14. Each planetary gear 27 is formed as a cylindrical body having a smaller diameter than the gear portion 26A of the sun gear 26, and is arranged in a planetary gear arrangement hole 32 described later. That is, three planetary gears 27 are provided in the circumferential direction between the sun gear 26 and the internal gear 14B (see FIG. 4). In this case, the upper surface 27A of the planetary gear 27 is arranged on the same plane as the upper surface 26A1 of the gear portion 26A of the sun gear 26. Each planetary gear 27 is rotatably supported by a gear support shaft 33 of the carrier 28 described later, and revolves around the sun gear 26 while rotating around the sun gear 26 between the sun gear 26 and the internal gear 14B.

  Reference numeral 28 denotes a carrier having a both-end support structure that rotatably supports each planetary gear 27. The carrier 28 is a circle having a slightly smaller diameter than the tip diameter of the internal gear 14B, as shown in FIGS. A plurality of plate-shaped upper support plates 29 and lower support plates 30 sandwiching the planetary gears 27 from the axial direction, and the upper and lower support plates 29 and 30 are connected to each other with a uniform spacing in the circumferential direction ( 3) connecting portions 31, and a gear support shaft 33 described later that rotatably supports the planetary gear 27 between the upper support plate 29 and the lower support plate 30.

  In the carrier 28, the upper support plate 29, the lower support plate 30, and the connecting portion 31 are integrally formed by, for example, casting. That is, the carrier 28 supports both ends of the upper and lower directions of the gear support shaft 33 by the upper support plate 29 and the lower support plate 30.

  The upper support plate 29 is provided with a sun gear insertion hole 29A through which the sun gear 26 is inserted at the center thereof, and three sun gear insertion holes 29A are positioned between the connecting portions 31 around the sun gear insertion hole 29A. An upper support shaft insertion hole 29B is formed. Between the lower end edge 29A1 of the sun gear insertion hole 29A and the sun gear 26, a gap 29C through which a thrust plate 37 described later is inserted is formed. An upper surface 38A of a thrust plate 37, which will be described later, is in contact with the lower surface 29D of the upper support plate 29.

  On the other hand, a cylindrical portion 30 </ b> A that protrudes toward the lower planetary gear reduction mechanism 24 is provided at the center of the lower support plate 30. A female spline portion 30B that is splined to the upper end side of the sun gear 24A of the lower planetary gear speed reduction mechanism 24 is formed on the inner peripheral side of the cylindrical portion 30A. Around the female spline portion 30B, lower support shaft insertion holes 30C are formed at positions corresponding to the upper support shaft insertion holes 29B of the upper support plate 29. That is, three lower support shaft insertion holes 30 </ b> C are formed between the connecting portions 31.

  Further, between each connecting portion 31 is a planetary gear arrangement hole 32 in which the planetary gear 27 is arranged. That is, the planetary gear 27 is rotated by a gear support shaft 33 (described later) while being disposed between the upper support shaft insertion hole 29B and the lower support shaft insertion hole 30C in the planetary gear arrangement hole 32. It is supported so as to mesh with the sun gear 26 and the internal gear 14B.

  Reference numeral 33 denotes a plurality of (three) gear support shafts supported at both ends by the upper support shaft insertion hole 29B of the upper support plate 29 and the lower support shaft insertion hole 30C of the lower support plate 30. The shaft 33 supports the planetary gear 27 in a rotatable manner. Each gear support shaft 33 is supported at both ends by being inserted into the upper support shaft insertion hole 29 </ b> B at the upper end side and inserted into the lower support shaft insertion hole 30 </ b> C at the lower end side. The planetary gear 27 is rotatably supported.

  In this case, the carrier 28 rotatably supports the planetary gear 27 by the respective gear support shafts 33, and each planetary gear 27 rotates by revolving around the sun gear 26, and this rotation is rotated to the lower planetary gear reduction mechanism. 24. Since a large rotational force (torque) is transmitted from the carrier 28 to the planetary gear reduction mechanism 24, a large load acts on the gear support shaft 33 that supports the planetary gear 27. Since each gear support shaft 33 is supported at both ends by the lower support plate 30 and the lower support plate 30, the load acting on the gear support shaft 33 can be reliably received. That is, the carrier 28 has a high strength by making the gear support shaft 33 have a dual-support structure.

  Reference numeral 35 denotes an annular plate disposed on the upper side of the female spline portion 30B of the lower support plate 30. The plate 35 includes the sun gear 26 of the upper planetary gear reduction mechanism 25 and the sun of the lower planetary gear reduction mechanism 24. Located between the gear 24A and the sun gear 26 is restricted from moving downward.

  Reference numeral 36 denotes an annular sliding plate provided between the lower support plate 30 and the planetary gear 27, and the sliding plate 36 smoothly rotates the planetary gear 27 with respect to the lower support plate 30. By this sliding plate 36, wear on the lower surface of the planetary gear 27 and the upper surface of the lower support plate 30 is suppressed.

  Next, the thrust plate 37 used in the first embodiment will be described.

  Reference numeral 37 denotes a thrust plate provided on one gear support shaft 33 among the three gear support shafts 33 of the carrier 28. The thrust plate 37 extends from the gear support shaft 33 toward the sun gear 26 and has a substantially glasses shape with a narrowed middle portion in the length direction. The thrust plate 37 is engaged with the sun gear 26 to restrict the sun gear 26 from moving along the motor shaft 19 of the hydraulic motor 15. The thrust plate 37 includes a support shaft side engaging portion 38, a constricted portion 39, and a sun gear side engaging portion 40.

  Reference numeral 38 denotes a support shaft side engaging portion that engages with the gear support shaft 33 of the carrier 28. It is smaller than the diameter dimension (tooth tip circle diameter) and larger than the outer diameter dimension of the gear support shaft 33 (see FIG. 4). Further, the support shaft side engagement portion 38 is formed with a support shaft side circular hole 38C penetrating from the upper surface 38A toward the lower surface 38B. The diameter dimension (hole diameter) of the support shaft side circular hole 38 </ b> C is substantially the same as or slightly larger than the outer diameter dimension of the gear support shaft 33. Thus, the support shaft side circular hole 38 </ b> C is inserted into the gear support shaft 33 and the support shaft side engaging portion 38 is engaged with the gear support shaft 33.

  In this case, the support shaft side engaging portion 38 is sandwiched between the planetary gear 27 and the upper support plate 29 of the carrier 28 (see FIG. 3). Thereby, the thrust plate 37 is restricted from moving in the upward and downward directions while rotating together with the carrier 28. As a result, the sun gear 26 is configured to be restricted from moving upward along the male spline portion 19 </ b> A of the motor shaft 19. Therefore, the meshing state between the sun gear 26 and the planetary gear 27 can be always kept good, so that the life of the sun gear 26 and the planetary gear 27 can be improved.

  Further, since the lower surface 38B of the support shaft side engaging portion 38 of the thrust plate 37 abuts (slides) on the upper surface 27A of the planetary gear 27, the planetary gear 27 can be smoothly rotated with respect to the upper support plate 29. Thus, wear of the upper surface 27A of the planetary gear 27 and the lower surface 29D of the upper support plate 29 can be suppressed.

  Reference numeral 39 denotes a constricted portion extending from the support shaft side engaging portion 38 toward the sun gear 26 side. The constricted portion 39 connects between the support shaft side engaging portion 38 and a sun gear side engaging portion 40 described later. To do. The constricted part 39 forms the same plane as the support shaft side engaging part 38 and the sun gear side engaging part 40 described later. A width direction dimension B of the constricted portion 39 is formed smaller than an outer diameter size C of a sun gear side engaging portion 40 which will be described later, and its outer shape is smooth from the sun gear side engaging portion 40 toward the constricted portion 39. (See FIG. 4).

  Here, when the sun gear side engagement portion 40 of the thrust plate 37 is engaged with the protrusion 26B of the sun gear 26, the thrust plate 37 is engaged with the sun gear 26 and the sun gear of the carrier 28 from the support shaft side engagement portion 38 side. The sun gear side circular hole 40C of the sun gear side engaging portion 40 is inserted into the projecting portion 26B of the sun gear 26 (see FIG. 5) by being inserted into the clearance 29C between the insertion hole 29A. In this case, the width dimension B of the constricted portion 39 is set such that both end edges 39A and 39B of the constricted portion 39 do not contact the lower end edge 29A1 of the sun gear insertion hole 29A of the carrier 28. In other words, the width dimension B of the constricted portion 39 is such that both end edges 39A, 39B of the constricted portion 39 dodge the lower end edge 29A1 of the sun gear insertion hole 29A when the thrust plate 37 is inserted and inserted into the gap 29C. Is set to a short dimension.

  Reference numeral 40 denotes a sun gear side engaging portion that extends from the constricted portion 39 toward the protruding portion 26B side of the sun gear 26. The sun gear side engaging portion 40 is a portion that engages with the protruding portion 26B of the sun gear 26. . The outer peripheral side of the sun gear side engaging portion 40 is formed in an arc shape, and its outer diameter C is smaller than the outer diameter (tooth diameter) of the gear 26A of the sun gear 26, and the outer diameter of the protrusion 26B. It is formed larger than the dimensions (see FIG. 4).

  The sun gear side engagement portion 40 is formed with a sun gear side circular hole 40C as a circular hole penetrating from the upper surface 40A toward the lower surface 40B. The diameter (hole diameter) of the sun gear side circular hole 40 </ b> C is slightly larger than the outer diameter of the protrusion 26 </ b> B of the sun gear 26. Thus, the sun gear side circular hole 40C can be inserted into the protruding portion 26B of the sun gear 26, and the lower surface 40B of the sun gear side engaging portion 40 can be brought into wide contact with the upper surface 26A1 of the sun gear 26. The upward movement of the gear 26 can be stably suppressed.

  In this case, the thrust plate 37 rotates together with the carrier 28, and the carrier 28 rotates at a speed reduced by the reduction ratio as compared with the rotation speed of the sun gear 26. As a result, friction caused by sliding between the sun gear 26 and the sun gear side engaging portion 40 of the thrust plate 37 can be reduced, so that the sliding wear amount, loss torque, and heat generation between the sun gear 26 and the thrust plate 37 are reduced. Can be suppressed.

  Further, the sun gear side engaging portion 40 that is a portion engaging with the sun gear 26 has an upper surface 40 </ b> A facing a lower end surface 16 </ b> C <b> 4 of the thrust plate contact portion 16 </ b> C <b> 2 of the motor housing 16. When the carrier 28 moves upward, the upper surface 40A of the sun gear side engagement portion 40 and the lower end surface 16C4 of the thrust plate contact portion 16C2 are in contact (sliding). Thereby, since it can suppress that a thrust load arises in the motor shaft 19, the burden concerning the hydraulic motor 15 can be reduced.

  Next, a procedure for assembling the upper planetary gear speed reduction mechanism 25 according to the first embodiment will be described.

  First, the plate 35 is inserted through the sun gear insertion hole 29 </ b> A formed in the upper support plate 29 of the carrier 28 and placed on the upper side of the female spline portion 30 </ b> B of the lower support plate 30. Then, the sun gear 26 is inserted through the sun gear insertion hole 29 </ b> A and placed on the plate 35.

  Next, the thrust plate 37 is inserted into the clearance 29C between the sun gear 26 and the sun gear insertion hole 29A from the support shaft side engaging portion 38 side, and the sun gear side circular hole of the sun gear side engaging portion 40 is inserted. 40C is inserted through the protrusion 26B of the sun gear 26. Thereby, the sun gear side engaging part 40 of the thrust plate 37 can be engaged with the sun gear 26.

  Here, a constricted portion 39 having a width dimension B smaller than the outer diameter dimension C of the sun gear side engaging portion 40 is formed at an intermediate portion in the length direction of the thrust plate 37. Thus, before the thrust plate 37 reaches a position where the sun gear side circular hole 40C can be inserted into the protruding portion 26B of the sun gear 26, the lower end edge 29A1 of the sun gear insertion hole 29A of the upper support plate 29 and This prevents the end edges 39A and 39B of the thrust plate 37 from abutting (interfering).

  Then, the support shaft side engagement portion 38 in a state where the support shaft side circular hole 38C of the support shaft side engagement portion 38 of the thrust plate 37 is positioned coaxially with the upper support shaft insertion hole 29B of the upper support plate 29. A planetary gear 27 and a sliding plate 36 are disposed on the lower side. Thereafter, the gear support shaft 33 is inserted into the upper support shaft insertion hole 29B, the support shaft side circular hole 38C of the thrust plate 37, the planetary gear 27, the sliding plate 36, and the lower support shaft insertion hole 30C. The upper planetary gear reduction mechanism 25 is assembled by inserting the upper and lower ends of the gear support shaft 33 into the upper support shaft insertion hole 29B and the lower support shaft insertion hole 30C. be able to.

  The construction machine turning device 11 according to the present embodiment has the above-described configuration. When hydraulic oil is supplied to the hydraulic motor 15 and the motor shaft 19 rotates, the rotation of the motor shaft 19 causes the rotation of the speed reducer 23. The planetary gear reduction mechanism 25 on the upper stage and the planetary gear reduction mechanism 24 on the lower stage are decelerated by two stages and transmitted to the output shaft 20, and the pinion 20B rotates with a large rotational force (torque). Then, the pinion 20B revolves along the inner ring 5A while meshing with the inner teeth 5D provided on the inner ring 5A of the turning wheel 5, and the revolution force of the pinion 20B is transmitted to the turning frame 3A. A turning operation is performed on the lower traveling body 2.

  In the present embodiment, the upper planetary gear speed reduction mechanism 25 uses the carrier 28 having a both-end support structure that supports both the upper and lower ends of the gear support shaft 33, thereby increasing the strength. ing. That is, since a large rotational force (torque) is transmitted from the carrier 28 of the planetary gear reduction mechanism 25 to the lower planetary gear reduction mechanism 24, a large load acts on the gear support shaft 33 that supports the planetary gear 27. The carrier 28 supports both the gear support shafts 33 by the upper support plate 29 and the lower support plate 30 so that the load acting on the gear support shaft 33 can be received with certainty.

  In this case, for example, when the sun gear 26 moves upward along the motor shaft 19, the meshing length between the sun gear 26 and the planetary gear 27 is shortened, and torque is transmitted with a small contact area. As a result, the contact surface pressure between the sun gear 26 and the planetary gear 27 is increased, and the life of the sun gear 26 and the planetary gear 27 may be reduced.

  Therefore, in the present embodiment, any one of the gear support shafts 33 of the carrier 28 is provided with a thrust plate 37 that restricts the sun gear 26 from moving along the motor shaft 19. Yes. The thrust plate 37 is a thin plate material extending between the sun gear 26 and the gear support shaft 33, and the planetary gear 27 and the upper support plate 29 in a state where the support shaft side engaging portion 38 is engaged with the gear support shaft 33. Is sandwiched between. Then, the lower surface 40B of the sun gear side engaging portion 40 of the thrust plate 37 is brought into contact with the upper surface 26A1 of the gear portion 26A of the sun gear 26 so that the sun gear 26 moves upward along the motor shaft 19. It is regulated.

  Thereby, it can suppress that the sun gear 26 moves upwards and the meshing length of the sun gear 26 and the planetary gear 27 becomes short. As a result, it is possible to suppress the contact surface pressure between the sun gear 26 and the planetary gear 27 from increasing, and to improve the life of the sun gear 26 and the planetary gear 27.

  Further, the carrier 28 rotates at a speed reduced by a reduction ratio as compared with the rotational speed of the sun gear 26, and the thrust plate 37 rotates together with the carrier 28. As a result, friction caused by sliding between the sun gear 26 and the thrust plate 37 can be reduced, so that sliding wear amount, loss torque, and heat generation between the sun gear 26 and the thrust plate 37 can be suppressed.

  A sun gear side circular hole 40 </ b> C is formed in the sun gear side engaging portion 40 of the thrust plate 37. As a result, the contact area between the upper surface 26A1 of the gear portion 26A of the sun gear 26 and the lower surface 40B of the sun gear side engaging portion 40 of the thrust plate 37 can be increased, so that the sun gear 26 moves upward. It can be stably suppressed.

  Further, when the carrier 28 moves upward, the thrust plate 37 contacts the lower end surface 16C4 of the thrust plate contact portion 16C2 provided on the lower end side of the motor housing 16, so that the thrust load is applied to the motor shaft 19. Can be suppressed. Thereby, the burden concerning the hydraulic motor 15 can be reduced.

  Further, the thrust plate 37 rotates at a speed reduced by a reduction ratio as compared with the rotational speed of the sun gear 26. As a result, the friction caused by sliding can be reduced as compared with the case where the sun gear 26 is in direct contact with the thrust plate contact portion 16C2, so that the sliding wear amount and loss torque of the sun gear 26 and the thrust plate contact portion 16C2 are reduced. , And heat generation can be suppressed.

  Next, FIGS. 7 to 9 show a second embodiment of the present invention. The feature of this embodiment is that a concave arc-shaped groove is formed in the sun gear side engaging portion of the thrust plate. is there. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

  A thrust plate 41 is used in place of the thrust plate 37 according to the first embodiment. The thrust plate 41 extends from the gear support shaft 33 toward the sun gear 26, and the sun gear 26 is a motor shaft of the hydraulic motor 15. 19 is restricted. The thrust plate 41 includes a support shaft side engaging portion 42, a constricted portion 43, and a sun gear side engaging portion 44.

  Reference numeral 42 denotes a support shaft side engaging portion that engages with the gear support shaft 33 of the carrier 28. The support shaft side engaging portion 42 is formed with a support shaft side circular hole 42C penetrating from the upper surface 42A toward the lower surface 42B. Has been. The diameter of the support shaft side circular hole 42 </ b> C is substantially the same as or slightly larger than the outer diameter of the gear support shaft 33. Thus, the support shaft side circular hole 42 </ b> C is inserted into the gear support shaft 33 and the support shaft side engaging portion 42 is engaged with the gear support shaft 33.

  In this case, the support shaft side engaging portion 42 is sandwiched between the planetary gear 27 and the upper support plate 29 of the carrier 28. As a result, the thrust plate 41 is restricted from moving in the upward and downward directions while rotating together with the carrier 28. As a result, the sun gear 26 is configured to be restricted from moving upward along the male spline portion 19 </ b> A of the motor shaft 19.

  43 is a constricted portion extending from the support shaft side engaging portion 42 toward the sun gear 26 side, and the constricted portion 43 connects between the support shaft side engaging portion 42 and a sun gear side engaging portion 44 described later. To do. The width direction dimension of the constricted part 43 is formed smaller than the width dimension E of the sun gear side engaging part 44 described later, and the outer shape thereof is smoothly recessed from the sun gear side engaging part 44 toward the constricted part 43. It is curved (see FIG. 7).

  Reference numeral 44 denotes a sun gear side engaging portion that extends from the constricted portion 43 toward the protruding portion 26B side of the sun gear 26. The sun gear side engaging portion 44 is a portion that engages with the protruding portion 26B of the sun gear 26. . The sun gear side engaging portion 44 is formed in a concave shape having an opening on one side in the length direction (see FIG. 9). Specifically, the sun gear side engaging portion 44 is formed with a concave arcuate groove 44C that penetrates from the upper surface 44A toward the lower surface 44B and engages with the protruding portion 26B of the sun gear 26 from the outer peripheral side. ing. The opening dimension D of the concave groove 44 </ b> C is slightly larger than the outer diameter dimension of the protruding portion 26 </ b> B of the sun gear 26. Further, the width E of the sun gear side engaging portion 44 is formed to be smaller than the minimum distance F between the adjacent connecting portions 31 of the carrier 28.

  Thus, as shown in FIG. 8, the thrust plate 41 is inserted from the planetary gear arrangement hole 32 formed between the upper support plate 29 and the lower support plate 30, and the sun gear side engaging portion 44 is inserted. The projecting portion 26B of the sun gear 26 can be engaged from the outer peripheral side. Therefore, since the thrust plate 41 can be easily engaged with the sun gear 26, the workability of the assembly work can be improved.

  In this case, the upper surface 44 </ b> A of the sun gear side engaging portion 44 faces the lower end surface 16 </ b> C <b> 4 of the thrust plate contact portion 16 </ b> C <b> 2 of the motor housing 16. When the carrier 28 moves upward, the upper surface 44A of the sun gear side engaging portion 44 and the lower end surface 16C4 of the thrust plate contact portion 16C2 are in contact (sliding).

  Thus, also in the swivel device for the construction machine according to the second embodiment configured as described above, the same operations and effects as those of the first embodiment can be obtained. In particular, in the present embodiment, a planetary gear disposed between the upper support plate 29 and the lower support plate 30 is formed by forming the concave groove 44C in the sun gear side engaging portion 44 of the thrust plate 41. By inserting the thrust plate 41 from the hole 32, the sun gear side engaging portion 44 can be engaged with the protruding portion 26B of the sun gear 26 from the outer peripheral side. Thereby, since the thrust plate 41 can be easily engaged with the sun gear 26, the workability of the assembly work can be improved.

  Next, FIGS. 10 and 11 show a third embodiment of the present invention. The feature of this embodiment is that the thrust plate is formed in a stepped shape. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

  A sun gear 51 is used in place of the sun gear 26 according to the first embodiment. The sun gear 51 includes a gear portion 51A that meshes with the planetary gear 27, and a protrusion that protrudes upward from the gear portion 51A. A stepped cylindrical body is formed by a part 51B and a female spline part 51C penetrating the gear part 51A and the protruding part 51B upward and downward (in the axial direction). As shown in FIG. 10, the upper surface of the gear portion 51A is stepped by a lower step surface 51A1 that is located on the same plane as the upper surface 27A of the planetary gear 27, and an upper step surface 51A2 that protrudes upward from the lower step surface 51A1. It is formed in a shape. That is, the upper step surface 51A2 is located above the upper surface 27A of the planetary gear 27.

  The protruding portion 51B protrudes upward from the upper step surface 51A2, and the female spline portion 51C of the sun gear 51 is splined to the male spline portion 19A formed on the lower end side of the motor shaft 19 of the hydraulic motor 15, The sun gear 51 rotates integrally with the motor shaft 19.

  A thrust plate 52 is used in place of the thrust plate 37 according to the first embodiment, and the thrust plate 52 regulates the movement of the sun gear 26 along the motor shaft 19 of the hydraulic motor 15. . The thrust plate 52 includes a support shaft side engaging portion 53, a stepped connecting portion 54, and a sun gear side engaging portion 55.

  53 is a support shaft side engaging portion that engages with the gear support shaft 33 of the carrier 28, and the support shaft side engaging portion 53 is engaged with the gear support shaft 33 and the upper support plate 29 of the carrier 28. It is sandwiched between the planetary gear 27 and extends in the horizontal direction toward the sun gear 26. The support shaft side engagement portion 53 is formed with a support shaft side circular hole 53C penetrating from the upper surface 53A toward the lower surface 53B. The diameter (hole diameter) of the support shaft side circular hole 53 </ b> C is substantially the same as or slightly larger than the outer diameter of the gear support shaft 33. Thus, the support shaft side circular hole 53 </ b> C is inserted into the gear support shaft 33 and the support shaft side engaging portion 53 is engaged with the gear support shaft 33.

  In this case, the support shaft side engaging portion 53 is sandwiched between the planetary gear 27 and the upper support plate 29 of the carrier 28 (see FIG. 10). As a result, the thrust plate 52 is restricted from moving upward and downward while rotating together with the carrier 28. As a result, the sun gear 51 is restricted from moving upward along the male spline portion 19A of the motor shaft 19.

  Reference numeral 54 denotes a stepped connecting portion extending obliquely upward from the support shaft side engaging portion 53 and having a step in the upper and lower directions. The stepped connecting portion 54 and the sun which will be described later. It connects with the gear side engaging part 55 with the level | step difference which inclined. The stepped connecting portion 54 is located closer to the sun gear 51 than the upper support plate 29 of the carrier 28 in a state where the thrust plate 52 is engaged with the gear support shaft 33 and the sun gear 51. The height of the stepped connecting portion 54 is the same as the height from the upper surface 27A of the planetary gear 27 to the upper step surface 51A2 of the sun gear 51.

  Further, the widthwise dimension of the stepped connecting portion 54 is formed to be smaller than the outer diameter size of the sun gear side engaging portion 55 described later, and the outer shape thereof is from the sun gear side engaging portion 55 to the stepped connecting portion 54. It is concavely curved smoothly toward (see FIG. 11). Thereby, the thrust plate 52 is inserted into the clearance 29C between the sun gear 51 and the sun gear insertion hole 29A of the carrier 28 from the support shaft side engaging portion 53 side, and the sun gear side engaging portion 55 of the thrust plate 52 is inserted. Is engaged with the sun gear 51, the thrust plate 52 can dodge the lower end edge 29A1 of the upper support plate 29.

  55 is a sun gear side engaging portion that extends from the stepped connecting portion 54 toward the protruding portion 51B side of the sun gear 51. The sun gear side engaging portion 55 is a portion that engages with the protruding portion 51B of the sun gear 51. It is. The sun gear side engaging portion 55 is formed in an arc shape on the outer peripheral side, and the outer diameter size thereof is smaller than the outer diameter size (tooth diameter) of the gear portion 51A of the sun gear 51, and the outer diameter size of the protruding portion 51B. It is formed larger than.

  Further, the sun gear side engagement portion 55 is formed with a sun gear side circular hole 55C as a circular hole penetrating from the upper surface 55A toward the lower surface 55B. The diameter (hole diameter) of the sun gear-side circular hole 55 </ b> C is slightly larger than the outer diameter of the protrusion 51 </ b> B of the sun gear 51. Accordingly, the sun gear side circular hole 55 </ b> C is inserted into the protruding portion 51 </ b> B of the sun gear 51, and the sun gear side engaging portion 55 can be engaged with the sun gear 51.

  In this case, the sun gear side engaging portion 55 extends in the horizontal direction toward the gear support shaft 33 in a state where the lower surface 55B is in contact (sliding) with the upper stage surface 51A2 of the sun gear 51. Further, the upper surface 55 </ b> A of the sun gear side engaging portion 55 faces the lower end surface 16 </ b> C <b> 4 of the thrust plate contact portion 16 </ b> C <b> 2 of the motor housing 16. When the carrier 28 moves upward, the upper surface 55A of the sun gear side engaging portion 55 and the lower end surface 16C4 of the thrust plate contact portion 16C2 are in contact (sliding).

  Thus, also in the swivel device for the construction machine of the third embodiment configured as described above, the same operations and effects as those of the first embodiment can be obtained. In particular, in the present embodiment, the stepped connecting portion 54 is formed between the support shaft side engaging portion 53 and the sun gear side engaging portion 55 of the thrust plate 52, so that the upper surface 27A of the planetary gear 27 Even when there is a step between the upper surface of the sun gear 51 (upper surface 51A2), the step can be absorbed by the stepped connecting portion 54. As a result, the thrust plate 52 can be assembled to the sun gear 51 and the gear support shaft 33 without rattling, so that the movement of the sun gear along the motor shaft can be stably controlled.

  In the second embodiment described above, the support shaft side engaging portion 42 of the thrust plate 41 is described as an example in which the support shaft side circular hole 42C that engages with the gear support shaft 33 is provided. did. However, the present invention is not limited to this. For example, as in the first modification shown in FIGS. 12 and 13, the thrust plate 61 includes a support shaft side engaging portion 62, a constricted portion 63, and a concave groove. The sun gear side engaging groove 64 having the sun gear side recessed groove 64 </ b> A may be used, and the support shaft side recessed groove 62 </ b> A may also be formed in the support shaft side engaging part 62. Thereby, since the thrust plate can be made as small and compact as possible, the yield can be improved. The same applies to the first and third embodiments.

  Further, in the second embodiment described above, the thrust plate 41 has been described by taking as an example the case where the constricted portion 43 having a width dimension smaller than the outer diameter dimension E of the sun gear side engaging portion 44 is formed. However, the present invention is not limited to this, and the width direction from the support shaft side engaging portion 72 of the thrust plate 71 to the sun gear side engaging portion 73 as in the second modification shown in FIGS. 14 and 15, for example. You may form a dimension into the same dimension. Thereby, since it is not necessary for the thrust plate to process the constricted portion, the workability of the manufacturing operation of the thrust plate can be improved.

  Further, in the first embodiment described above, a constricted portion is provided in which the outer shape of the thrust plate 37 is formed in a concave curved shape on both end sides from the sun gear side engaging portion 40 toward the support shaft side engaging portion 38. The case has been described as an example. However, the present invention is not limited to this. For example, the diameter may be gradually reduced so as to taper from the sun gear side engaging portion toward the support shaft side engaging portion. Further, the width dimension of the connecting part may be substantially the same as the outer diameter dimension of the support shaft side engaging part, and the outer shape on both ends of the connecting part may be formed linearly. The same applies to the second and third embodiments and the first modification.

  Further, in the above-described third embodiment, an example is given in which the connecting portion is a stepped connecting portion 54 that is inclined obliquely upward from the support shaft side engaging portion 53 toward the sun gear side engaging portion 55. Explained. However, the present invention is not limited thereto, and for example, the stepped connecting portion may be a vertical portion that rises approximately 90 degrees upward from the support shaft side engaging portion toward the sun gear side engaging portion.

  In the above-described third embodiment, the case where the substantially glasses-shaped thrust plate 52 is formed in a stepped shape has been described as an example. However, the present invention is not limited to this. For example, the thrust plate 41 according to the second embodiment may be formed in a stepped shape. The same applies to the first and second modified examples.

  In the above-described embodiment, the case where the hydraulic motor 15 is used as the swing motor has been described as an example. However, the present invention is not limited to this. For example, an electric motor may be used as the turning motor.

  In the above-described embodiment, the swivel device 11 of the excavator 1 has been described as an example. However, the present invention is not limited to this, and can be widely applied to other construction machines such as a hydraulic crane.

1 Excavator (construction machine)
DESCRIPTION OF SYMBOLS 2 Lower traveling body 3 Upper turning body 5 Turning wheel 11 Turning apparatus 12 Housing 13 Lower housing 14 Upper housing 14B Internal gear 15 Hydraulic motor (swing motor)
16 Motor housing 16C Bearing housing portion 16C2 Thrust plate contact portion 17 Bearing 19 Motor shaft 20 Output shaft 24 Lower planetary gear reduction mechanism 25 Upper planetary gear reduction mechanism 26, 51 Sun gear 26A, 51A Gear portion 26B, 51B Projection 27 planetary gear 28 carrier 29 upper support plate 29D lower surface 30 lower support plate 33 gear support shaft 37, 41, 52, 61, 71 thrust plate 38, 42, 53, 62, 72 support shaft side engaging portion 40, 44, 55 , 64, 73 Sun gear side engagement part 40C, 55C Sun gear side circular hole (circular hole)
44C Concave groove 54 Stepped connection part (connection part)
64A sun gear side ditch (ditch)

Claims (5)

A cylindrical housing that is attached to an upper swing body that is turnably mounted on a lower traveling body via a swirl wheel and that extends upward and downward, a swing motor provided on an upper end side of the housing, and a housing A planetary gear speed reduction mechanism that decelerates rotation of the turning motor, and an output shaft that outputs the rotation of the turning motor decelerated by the planetary gear speed reduction mechanism to turn the turning wheel,
The planetary gear reduction mechanism includes a sun gear splined to the motor shaft of the swing motor, a plurality of planetary gears that mesh with the sun gear and an internal gear and revolve around the sun gear, In a swiveling device for a construction machine comprising a gear support shaft that rotatably supports each planetary gear, and a carrier that supports both ends of the upper and lower directions of each gear support shaft.
A configuration is provided in which one of the gear support shafts of the carrier is provided with a thrust plate that engages with the sun gear and restricts the sun gear from moving along the motor shaft of the swing motor. A swiveling device for a construction machine characterized by the above. The sun gear is constituted by a gear portion that meshes with each planetary gear, and a circular protruding portion that protrudes upward from the gear portion,
The said thrust plate is comprised by the support shaft side engaging part engaged with the gear support shaft of the said carrier, and the sun gear side engaging part engaged with the protrusion part of the said sun gear. Swivel device for construction machinery.   The sun gear side engaging portion of the thrust plate is formed with a circular hole inserted into the projecting portion of the sun gear or a concave arc-shaped groove that engages with the projecting portion of the sun gear from the outer peripheral side. The turning device for a construction machine according to claim 2. The carrier has an upper support plate and a lower support plate that support both end portions of the gear support shafts in a state where the planetary gears are sandwiched from the axial direction.
The thrust plate is held between the upper support plate of the carrier and the planetary gear while being engaged with the gear support shaft, and the support shaft side engaging portion extending in the horizontal direction toward the sun gear; The sun gear side engaging portion that is in contact with the upper surface of the gear portion of the sun gear and that extends in the horizontal direction toward the gear support shaft in a state of being engaged with the projecting portion of the sun gear, and the support shaft side engaging portion 4. The swivel device for a construction machine according to claim 2, wherein the swivel device is formed in a stepped manner by a connecting portion that connects the sun gear side engaging portion with a step in an upward and downward direction. 5. The swing motor has a motor housing that houses a rotation source therein,
Provided on the lower end side of the motor housing is a bearing housing portion for housing a bearing that supports the motor shaft,
The bearing housing portion is provided with a thrust plate contact portion protruding toward the sun gear,
The construction machine according to claim 1, 2, 3, or 4, wherein a portion of the thrust plate that engages with the sun gear is arranged between the sun gear and the thrust plate contact portion. Swivel.

Images