JP2005061579A - Swing device for construction machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To deconcentrate reaction on a housing and reduce the size thereof by providing a ring gear in a motor case for meshing with a first stage reduction mechanism. <P>SOLUTION: A first ring gear 15 is provided in a reduction gear storage part 13B of the motor case 13 for meshing with a planetary gear 21B of the reduction mechanism 21 and a second ring gear 20 is provided in a cylinder part 17A of the housing 17 for meshing with a planetary gear 22B of the next stage reduction mechanism 22. Thus, the shell of a swing device 11 is constructed by two members, the motor case 13 and the housing 17, achieving simplified construction. Reaction on the motor case 13 is reduced by an equivalent of the reduction mechanism 22 and the outer diameter of flanges 13C, 17B and the layout of upper bolts 28 are reduced in the radial direction, therefore smoothing fastening work for lower bolts 29 at the upper side of the swing device 11, e.g. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a turning device for a construction machine that is suitably used for, for example, a hydraulic excavator, a hydraulic crane, and the like.

  Generally, in construction machines such as a hydraulic excavator and a hydraulic crane, a turning device is provided between a lower traveling body and an upper turning body (see, for example, Patent Document 1).

  A swivel device according to this type of prior art includes a motor case in which a hydraulic motor is housed, a cylindrical housing provided below the motor case and attached to the vehicle body, and attached to the upper side of the housing. Two or more speed reduction mechanisms provided in a reduction gear housing space defined by the housing and a motor case, and rotation of the hydraulic motor provided rotatably in the housing and decelerated by the speed reduction mechanisms Is output to the vehicle body side.

  The turning device decelerates the rotation of the hydraulic motor by each speed reduction mechanism, and outputs a large rotational force from the output shaft to the lower traveling body side, thereby turning the upper revolving body on the lower traveling body by this rotational force. It is.

  Here, the housing is configured by connecting a cylindrical upper housing and a lower housing, and the upper housing and the lower housing are fastened with a plurality of upper bolts and the like in a state of being in contact with each other. Each of the housing connecting flanges is provided.

  The upper housing is integrally formed with two ring gears spaced apart in the upward and downward directions. The upper ring gear meshes with the planetary gear of the first-stage reduction mechanism, and the lower ring gear meshes with the planetary gear of the second-stage reduction mechanism.

  Further, a lower flange that protrudes radially outward is provided on the lower side of the lower housing, and the lower flange is fixed to the swing frame of the upper swing body using a plurality of lower bolts or the like.

  In this case, when the turning device is fixed to the vehicle body side, for example, tightening is performed on a narrow gap between the turning device mounted on the turning frame of the upper turning body and another vehicle-mounted structure (building) or the like. In many cases, a long and narrow tool such as a wrench is inserted from above, and the lower bolt is tightened using this tool.

  For this reason, the housing connection flange located on the front side of the gap when viewed from the upper side of the swivel device is formed with a smaller outer diameter than the lower flange located on the back side of the gap. The housing connecting flange is configured not to get in the way when it is inserted and tightened.

JP-A-9-144854

  By the way, in the above-described prior art, a large reaction force is applied to the upper housing when the hydraulic motor and the first-stage and second-stage reduction mechanisms rotate. For this reason, not only the main body portion of the upper housing but also the housing connection flange, the upper bolt, and the like constituting the connection portion between the upper housing and the lower housing need to be strong enough to receive a large reaction force. As a result, when designing the swivel device, for example, it is necessary to increase the bolt diameter of the upper bolt, or to sufficiently increase the thickness of the upper housing and the outer diameter of the housing connecting flange.

  However, if the housing dimensions and bolt diameter are simply increased, the entire housing will become larger in the radial direction, so that when the lower bolt is tightened, the housing connection flange etc. will obstruct the gap between the turning device and the building. The tool may not be inserted smoothly. Also, even if only the upper ring gear is expanded without increasing the size of the entire housing, for example, the expanded portion projects so as to cover the housing connecting flange from the upper side. It becomes difficult.

  In this way, if these strengths are to be ensured while taking into account the upper housing dimensions and bolt diameter limitations, for example, the upper and lower ring gears are thickened radially inwardly, Often the inner diameter must be reduced.

  For this reason, in the prior art, the number of teeth of the ring gear may be limited, the number of teeth of the sun gear and the planetary gear, and the dimensions of the support pins and bearings that support the planetary gear may be limited. There is a problem that it becomes difficult to realize the reduction ratio, and the degree of freedom in design is 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 secure the strength of the housing while suppressing the outer diameter of the housing in the vicinity of the ring gear, and to determine the number of teeth, dimensions, etc. An object of the present invention is to provide a swivel device for a construction machine that can alleviate the restriction and can improve the degree of design freedom.

  In order to solve the above-described problems, the present invention provides a motor case in which a hydraulic motor is housed, a cylindrical housing that is provided on the lower side of the motor case and attached to the vehicle body side, and an upper side of the housing. Two or more stages of reduction mechanisms provided in a reduction gear housing space defined by the housing and the motor case, and rotation of the hydraulic motor provided in the housing and rotated by the reduction mechanisms. Is applied to a turning device of a construction machine including an output shaft that outputs the power to the vehicle body side.

  According to the first aspect of the present invention, the motor case is provided with a first ring gear that meshes with the first-stage reduction mechanism among the reduction mechanisms, and the housing has the second-stage reduction mechanism. The second ring gear to be engaged is provided.

  According to a second aspect of the present invention, the motor case includes a motor housing portion that houses the hydraulic motor, and a cylindrical reduction gear that is provided on the lower side of the motor housing portion and has a first ring gear formed on the inner peripheral side. It is comprised by the machine accommodating part.

  According to a third aspect of the present invention, the housing is provided on the inner peripheral side of the cylindrical portion, the cylindrical portion having the second ring gear formed on the inner peripheral side, and positioned below the second ring gear. And a bearing mounting portion to which a bearing that rotatably supports the output shaft is mounted.

  According to a fourth aspect of the present invention, the motor case side flange is provided on the lower side of the motor case, and the housing side upper flange that is brought into contact with the motor case side flange is provided on the upper side of the motor case. The case-side flange and the housing-side upper flange are fastened using bolts, and the bolts are disposed at radial dimension positions substantially equal to the outer peripheral surface of the housing.

  According to the first aspect of the present invention, the motor case is provided with the first ring gear engaged with the first stage reduction mechanism, and the housing is provided with the second ring gear engaged with the second stage reduction mechanism. Therefore, the outer shell of the swivel device can be constituted by two members including the motor case and the housing, and the number of parts can be reduced to simplify the structure.

  When the swing device is operated, the reaction force when the hydraulic motor and the first-stage reduction mechanism rotate can be received by the motor case, and the reaction force from the second-stage reduction mechanism can be received by the housing. The reaction force receiving site can be dispersed. As a result, the reaction force applied to the motor case and the housing, compared to the case where all the reaction forces due to the hydraulic motor and the first and second stage reduction mechanisms are applied to one housing as in the prior art, The reaction force applied to the connecting portion between the housing and the housing can be reduced, and even if these portions are miniaturized and the strength is suppressed to some extent, the durability of the swivel device can be sufficiently ensured.

  Therefore, even if the thickness of the motor case is not increased excessively, it can be formed to a required strength, and when the swivel device is designed, for example, the restriction on strength on the number of teeth, dimensions, etc. of the first ring gear is relaxed. be able to. For this reason, compared with the prior art, the number of teeth, dimensions, etc. of the ring gear and the speed reduction mechanism can be set freely, each part can be efficiently designed to have a desired speed reduction ratio, and the degree of design freedom can be increased. . Further, since it is not necessary to increase the strength by forcibly increasing the diameter of the motor case, the turning device can be formed compact in the radial direction.

  According to the invention of claim 2, since the motor case is constituted by the motor housing portion and the speed reducer housing portion, the first stage speed reduction mechanism can be housed in the speed reducer housing portion of the motor case. Can accommodate the second-stage reduction mechanism, and the structure of the entire apparatus can be simplified.

  And since the motor case does not receive reaction force from the second-stage reduction mechanism, it is necessary for these parts without forcibly increasing the thickness of the reducer housing and the outer diameter of the connection part with the housing. Strength can be given. As a result, the outer diameter dimension of the reduction gear housing can be made small enough not to receive a reaction force from the second-stage reduction mechanism, and the structure of the swivel device can be simplified and assembly work can be performed smoothly.

  Further, according to the invention of claim 3, since the housing is constituted by the cylindrical portion in which the second ring gear is formed on the inner peripheral side and the bearing mounting portion provided on the inner peripheral side of the cylindrical portion, The cylindrical portion of the housing can accommodate the second-stage reduction mechanism, and can rotatably support the output shaft via a bearing. Since the housing receives only a relatively small reaction force from the first-stage reduction mechanism, the strength of the housing can be suppressed to some extent and the structure can be simplified.

  According to the invention of claim 4, the bolt for fastening the motor case side flange and the housing side upper flange is arranged at a radial dimension position substantially equal to the outer peripheral surface of the housing. Considering that the reaction force from the speed reduction mechanism is distributed to the motor case and the housing so that the reaction force applied to the bolts for fastening them is reduced by the second speed reduction mechanism. Can be disposed at a position that is substantially equal to the outer peripheral surface of the housing, that is, a position that does not protrude greatly radially outward from the housing.

  As a result, the entire motor case (swivel device) including the arrangement of bolts, the outer diameter of each flange, and the like can be reduced in the radial direction. Even in such a configuration, the strength required for the connecting portion between the motor case and the housing is increased. Can be given. As a result, it is possible to prevent the flange, bolt, etc. from protruding outward in the radial direction. For example, even when a tool is inserted from the upper side of the swivel device to the lower side (back side) of the flange, this work is performed. Can be easily performed.

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

  In the figure, reference numeral 1 denotes a hydraulic excavator. The hydraulic excavator 1 is mounted on a self-propelled lower traveling body 2 and is pivotably mounted on the lower traveling body 2 via a swivel wheel 3. A cab, a building cover, a counter The upper swing body 4 is provided with weights and the like, and the working device 5 is provided on the front side of the upper swing body 4 so as to be able to move up and down and performs excavation work such as earth and sand.

  Here, as shown in FIGS. 1 and 2, the swivel wheel 3 is composed of, for example, a ball bearing or the like, and is positioned on the outer ring side of the inner ring 3A and the inner ring 3A fixed to the circular body 2A of the lower traveling body 2. The outer ring 3B is fixed to the swing frame 4A of the upper swing body 4 and a plurality of steel balls 3C (only one is shown) that rotatably connects the inner ring 3A and the outer ring 3B. An annular inner tooth 3D is formed over the entire circumference on the inner circumference side of the inner ring 3A.

  Reference numeral 11 denotes a turning device provided between the lower traveling body 2 and the upper turning body 4. The turning device 11 includes a hydraulic motor 12, a housing 17, and planetary gear speed reduction mechanisms 21 and 22, which will be described later, as shown in FIG. The output shaft 23 is generally configured.

  Reference numeral 12 denotes a hydraulic motor that constitutes a turning motor of the hydraulic excavator 1, and the hydraulic motor 12 includes a motor case 13, a rotating shaft 16, and the like, which will be described later. The hydraulic motor 12 is supplied and discharged with hydraulic oil from a hydraulic pump (not shown) or the like mounted on the upper swing body 4, and the rotating shaft 16 rotates to rotate the upper swing body 4 on the lower traveling body 2. Is to turn.

  Reference numeral 13 denotes a cylindrical motor case constituting an outer shell of the hydraulic motor 12, and the motor case 13 is a motor in which a drive unit (not shown) of the hydraulic motor 12 is accommodated as shown in FIGS. A housing portion 13A, a substantially cylindrical reduction gear housing portion 13B that is provided on the lower side of the motor housing portion 13A and that defines a speed reducer housing space K in which a speed reduction mechanism 21 described later is housed; An annular motor case side flange 13 </ b> C projecting radially outward from the lower side of the speed reducer housing portion 13 </ b> B and a ring gear 15 described later are configured.

  Here, the motor case side flange 13C has an outer diameter dimension substantially equal to a housing side upper flange 17B described later. These outer diameter dimensions are formed to be smaller than the outer diameter dimension of the housing-side lower flange 17C, and are configured not to obstruct the tightening operation of the lower bolt 29 shown in FIG.

  Further, as shown in FIG. 4, the motor case side flange 13 </ b> C is provided with a plurality of bolt insertion holes 14 (only two are shown) through which an upper bolt 28 (described later) is inserted with an interval around the entire circumference. And the centerline of each bolt insertion hole 14 is arrange | positioned in the radial direction dimension position substantially equal to the outer peripheral surface 17F of the housing 17, as shown to Formula 1 mentioned later.

  Reference numeral 15 denotes a first ring gear provided in the speed reducer accommodating portion 13B of the motor case 13, and the first ring gear 15 is formed as a circular inner tooth centered on the rotating shaft 16, and is a first stage described later. And the planetary gears 21B of the speed reduction mechanism 21. Further, the ring gear 15 is disposed on the deeper side than the opening end (motor case side flange 13C) of the motor case 13, and is integrally formed on the inner peripheral side of the reduction gear housing 13B.

  Here, during the operation of the turning device 11, the reaction force when the hydraulic motor 12 and the first stage reduction mechanism 21 rotate is received by the motor case 13 via the ring gear 15, and the second stage reduction mechanism 22. The reaction force is received by the housing 17 via the ring gear 20. As a result, compared to the case where all these reaction forces are applied to one housing (upper housing) as in the prior art, these reaction forces can be distributed to the motor case 13 and the housing 17, and the motor case 13 and the housing The reaction force applied to each of 17 can be reduced.

  Thereby, in this embodiment, for example, without forcibly increasing the outer diameter of the reduction gear housing 13B and the motor case side flange 13C of the motor case 13 or reducing the inner diameter on the tooth bottom side of the ring gear 15, Necessary strength can be imparted to these parts, and the restriction on the strength with respect to the outer diameter of the motor case 13, the number of teeth of the ring gear 15, dimensions, etc. can be relaxed.

  Reference numeral 16 denotes a rotating shaft rotatably supported in the motor case 13, and the rotating shaft 16 is formed to extend downward from the motor housing portion 13A of the motor case 13 into the speed reducer housing portion 13B. Is spline-coupled to a sun gear 21A of a reduction mechanism 21 described later.

  Reference numeral 17 denotes a housing that constitutes the outer shell of the turning device 11 together with the motor case 13, and the housing 17 is formed in a cylindrical shape from a metal material or the like as shown in FIGS. Both sides are open. The housing 17 defines a speed reducer accommodation space K for accommodating speed reduction mechanisms 21 and 22 described later in cooperation with the speed reducer accommodation portion 13 </ b> B of the motor case 13.

  Here, the housing 17 includes a cylindrical portion 17A extending upward and downward, an annular housing-side upper flange 17B protruding radially outward from the upper side of the cylindrical portion 17A, and a diameter from the lower side of the cylindrical portion 17A. An annular housing-side lower flange 17C projecting outward in the direction, and an annular bearing mounting portion 17D, which is provided on the inner peripheral side of the cylindrical portion 17A so as to be spaced upward and downward, and to which bearings 24 and 25 described later are mounted. 17E and a ring gear 20 described later.

  As shown in FIG. 4, the cylindrical portion 17A has a cylindrical outer peripheral surface 17F having a constant diameter A. The housing side upper flange 17B and the housing side lower flange 17C have a diameter larger than that of the outer peripheral surface 17F. Projects outward in the direction. Further, a plurality of screw holes 18 into which the upper bolts 28 are screwed are provided on the upper end surface of the housing 17 at intervals over the entire circumference, and the housing-side upper flange 17B is in contact with the motor case-side flange 13C. Each upper bolt 28 is fastened to the flange 13C.

  On the other hand, the housing-side lower flange 17C is provided with a plurality of bolt insertion holes 19 through which the respective lower bolts 29 are inserted at intervals over the entire circumference. It is fixed to the turning frame 4A.

  Reference numeral 20 denotes a second ring gear provided in the cylindrical portion 17A of the housing 17, and the second ring gear 20 is integrally formed on the upper inner peripheral side of the cylindrical portion 17A as an inner tooth having a diameter larger than that of the upper ring gear 15. These mesh with the planetary gears 22B of the second-stage reduction mechanism 22 described later.

  21 is a first-stage planetary gear speed reduction mechanism provided in the speed reducer accommodating portion 13B of the motor case 13, and the planetary gear speed reduction mechanism 21 is a rotating shaft 16 of the hydraulic motor 12 as shown in FIGS. A plurality of planetary gears 21B (only one is shown) that meshes with the sun gear 21A and the ring gear 15 of the motor case 13 and revolves around the sun gear 21A. A carrier 21C that rotatably supports each planetary gear 21B. In this case, each planetary gear 21B is rotatably supported via a bearing 21E by a support pin 21D provided on the carrier 21C.

  Reference numeral 22 denotes a second stage planetary gear reduction mechanism provided in the cylindrical portion 17A of the housing 17, and the planetary gear reduction mechanism 22 is housed in the reduction gear housing space K together with the first stage planetary gear reduction mechanism 21. A sun gear 22A splined to the carrier 21C, a plurality of planetary gears 22B meshing with the sun gear 22A and the ring gear 20 of the housing 17 and revolving around the sun gear 22A, The carrier 22C is configured to rotatably support the planetary gear 22B.

  Reference numeral 23 denotes an output shaft provided in the housing 17 so as to extend in the axial direction. The output shaft 23 is formed in a stepped columnar shape, and is supported by bearings 24 and 25 attached to bearing mounting portions 17D and 17E of the housing 17. It is rotatably supported.

  Here, the carrier 22 </ b> C of the second stage planetary gear speed reduction mechanism 22 is splined to the upper side of the output shaft 23. A nut member 26 that pressurizes the bearings 24 and 25 in the axial direction is screwed onto the outer peripheral side of the output shaft 23. A pinion 27 that meshes with the internal teeth 3 </ b> D of the swivel wheel 3 is provided on the lower side of the output shaft 23.

  The output shaft 23 is rotationally driven by the hydraulic motor 12 via the planetary gear speed reduction mechanisms 21 and 22, and the rotation of the hydraulic motor 12 decelerated by the speed reduction mechanisms 21 and 22 is transmitted from the pinion 27 to the turning wheel 3. This is output to the inner ring 3A side.

  Reference numeral 28 denotes a plurality of upper bolts (only two are shown) that connect the motor case 13 and the housing 17, and each upper bolt 28 is composed of, for example, a hexagon socket head bolt or the like. The motor case side flange 13 </ b> C and the housing side upper flange 17 </ b> B are fastened together with the screw holes 18 of the housing 17.

  Here, the upper bolts 28 are arranged at intervals over the entire circumference of the flanges 13C and 17B, and the center lines of the individual upper bolts 28 are arranged on a circumference having a constant diameter B as shown in FIG. Is arranged in. The diameter B is formed to have a size substantially equal to the diameter A of the outer peripheral surface 17F of the housing 17 as shown in the equation 1 below, and each upper bolt 28 is substantially equal to the outer peripheral surface 17F of the housing 17. It is arranged at a radial dimension position.

  In this case, since the reaction force is not applied from the second-stage reduction mechanism 22 to the connecting portion between the motor case 13 and the housing 17, the motor case side flange 13C, the housing side upper flange 17B, the upper bolt 28, etc. Even if the strength is suppressed, the durability of the turning device 11 can be sufficiently ensured.

  For this reason, the upper bolt 28 is disposed at a radially inner position substantially equal to the outer peripheral surface 17F of the housing 17, and a bolt having a smaller bolt diameter is used as compared with the prior art. As a result, the outer diameter of the flanges 13C and 17B is also smaller than that of the prior art. As a result, the motor case 13 can be formed compact in the radial direction as a whole, and even with such a configuration, sufficient strength can be given to the motor case 13 and the connection portion between the motor case 13 and the housing 17.

  Reference numeral 29 denotes a plurality of lower bolts (only two are shown) for fixing the housing 17 to the swing frame 4A of the upper swing body 4. The lower bolts 29 are arranged at intervals over the entire circumference of the housing-side lower flange 17C. The bolts are screwed into the turning frame 4 </ b> A through 17 bolt insertion holes 19.

  In this case, the center lines of the individual lower bolts 29 are arranged side by side on a circumference having a certain diameter C as shown in FIG. This diameter C is formed sufficiently large with respect to the diameter B of the arrangement of the upper bolts 28 set substantially equal to each other and the diameter A of the outer peripheral surface 17F of the housing 17 as shown in the following equation (1). And arranged on the outer side in the radial direction of the flanges 13C and 17B.

  For this reason, when the turning device 11 is fixed to the upper turning body 4, as shown in FIG. 5, tightening is performed between the turning device 11 and the building 30 made of various structures provided on the turning frame 4 </ b> A. When a rod-shaped tool 31 made of a wrench or the like is inserted, a sufficiently large gap S can be secured between the tool 31 and the flanges 13C and 17B, and the tightening operation of each lower bolt 29 using the tool 31 is smooth. Can be done.

  The excavator turning device 11 according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  First, when assembling the swivel device 11, each upper bolt 28 is inserted into each bolt insertion hole 14 of the motor case 13, and is tightened and screwed into the screw hole 18 of the housing 17. And conclude. Moreover, the speed reduction mechanisms 21 and 22 are accommodated in the speed reducer accommodation space K defined inside them.

  In this case, the motor case 13 is formed compact in the radial direction as described above, and the speed reducer accommodating portion 13B and the like are disposed radially inward from the motor case side flange 13C. For this reason, when the upper bolt 28 is tightened, a tightening tool or the like does not interfere with the outer peripheral side of the motor case 13, and the tightening operation can be smoothly performed from the upper side of the flange 13C.

  Further, when the turning device 11 is mounted on the upper turning body 4, the lower bolts 29 are tightened as shown in FIG. 5. In this operation, first, a tool 31 such as a tightening wrench is inserted between the building 30 of the upper swing body 4 and the swing device 11 from the upper side of the swing device 11, and its tip side is engaged with the lower bolt 29. And the lower volt | bolt 29 is tightened by rotating the tool 31 in this state.

  At this time, a sufficiently large gap S or the like is secured between the flanges 13C and 17B on the swivel device 11 side and the building 30 and between the flanges 13C and 17B and the tool 31. The tool 31 can be inserted from the front side toward the lower bolt 29 on the back side, and the work can be easily rotated to tighten the lower bolt 29.

  When the turning device 11 is operated, when the hydraulic hydraulic motor 12 is operated in accordance with the driving operation of the vehicle operator, the rotation of the rotating shaft 16 is decelerated by the planetary gear reduction mechanisms 21 and 22 and output as a large rotational force. It is transmitted from the pinion 27 of the shaft 23 to the inner ring 3A of the turning wheel 3. For this reason, the upper swing body 4 fixed to the outer ring 3 </ b> B side performs a swing operation on the lower traveling body 2 together with the swing device 11.

  At this time, since the reaction force generated when the hydraulic motor 12 and the speed reduction mechanisms 21 and 22 rotate is distributed and received by the motor case 13 and the housing 17, the flanges 13C and 17B and the upper bolts are received. Even if 28 is downsized in the radial direction, the durability of the turning device 11 can be sufficiently increased.

  Thus, according to the present embodiment, the reduction gear accommodating portion 13B of the motor case 13 is provided with the ring gear 15 that meshes with the first-stage reduction mechanism 21, and the cylindrical portion 17A of the housing 17 is provided with the second-stage reduction gear 21. Since the ring gear 20 that meshes with the speed reduction mechanism 22 is provided, the speed reduction mechanism 21 can be accommodated in the speed reducer accommodation portion 13B, and the speed reduction mechanism 22 can be accommodated in the cylinder portion 17A.

  As a result, the outer shell of the turning device 11 can be constituted by two members including the motor case 13 and the housing 17, the number of parts of the turning device 11 can be reduced, the structure of the housing can be simplified, and at the time of assembly. Workability etc. can be improved.

  In addition, the reaction force applied to the motor case 13 and the housing 17 can be reduced as compared with the case where all the reaction forces generated by the hydraulic motor 12 and the speed reduction mechanisms 21 and 22 are applied to one housing as in the prior art. it can. As a result, when designing the swivel device 11, for example, the reduction gear housing 13B (the bottom side of the ring gear 15) can be formed to the required strength without forcibly increasing the thickness toward the inner peripheral side. The restriction on the strength with respect to the number of teeth, dimensions, etc. of 15 can be relaxed.

  Therefore, the number of teeth, dimensions, etc. of the ring gear 15 can be freely set as compared with the prior art, and accordingly, the number of teeth of the sun gear 21A and the planetary gear 21B of the speed reduction mechanism 21, the support pins 21D, the bearing 21E, etc. Therefore, the parts can be efficiently designed so that the speed reduction mechanism 21 has a desired speed reduction ratio, and the selection range of the speed reduction ratio and the like can be expanded to increase the degree of freedom in design.

  Further, since it is not necessary to increase the strength by forcibly increasing the diameter of the reduction gear housing 13B and the like, the outer diameter of this part can be reduced so as not to protrude above the motor case side flange 13C. At the time of assembly, the upper bolt 28 can be smoothly tightened from above with respect to the motor case side flange 13C.

  Further, since the reaction force applied to the motor case side flange 13C, the housing side upper flange 17B and the upper bolts 28 constituting the connecting portion of the motor case 13 and the housing 17 can be reduced, the outer diameter dimensions of the flanges 13C and 17B are reduced according to the prior art. Smaller than that.

  Each upper bolt 28 can be downsized, and the diameter B of the arrangement can be made substantially equal to the diameter A of the outer peripheral surface 17F of the housing 17, so that these upper bolts 28 are substantially equal to the outer peripheral surface 17F of the housing 17. It can arrange | position in the position inside radial direction.

  Thus, for example, the members such as the flanges 13C and 17B and the upper bolt 28 that are located on the front side of the lower bolt 29 when viewed from the upper side of the turning device 11 are formed so as not to protrude above the lower bolt 29. It can be arranged compactly in the direction. Accordingly, the lower bolt 29 can be easily tightened from the upper side of the turning device 11 using the tool 31 or the like.

  Further, for example, when the outer diameters of the flanges 13C and 17B are expanded to the same size as that of the prior art, the radial dimensions of the ring gears 15 and 20 and the speed reduction mechanisms 21 and 22 positioned inside thereof are increased. Thus, the selection range of the number of teeth, dimensions, etc. can be further expanded, and the turning device 11 having a wide adaptive range such as the reduction ratio can be realized.

  On the other hand, since the ring gear 20 and the bearing mounting portions 17D and 17E are provided in the cylindrical portion 17A of the housing 17, the second-stage reduction mechanism 22 and the output shaft 23 are accommodated in the cylindrical portion 17A. Can do.

  In the embodiment, the two-stage planetary gear reduction mechanisms 21 and 22 are provided in the turning device 11. However, the present invention is not limited to this. For example, a configuration in which three or more planetary gear reduction mechanisms are provided may be used. In this case, for example, the first ring gear that meshes with the planetary gear of the first-stage reduction mechanism is provided in the motor case, and the second ring gear that meshes with the planetary gear of the second-stage or later reduction mechanism is housed in the housing. It is sufficient to adopt a configuration provided in

  In the embodiment, the case where the present invention is applied to the turning device 11 of the excavator 1 is described as an example. However, the present invention is not limited to this, and may be applied to a turning device of another construction machine such as a hydraulic crane.

It is a front view which shows the hydraulic excavator applied to embodiment of this invention. It is a longitudinal cross-sectional view which shows the turning apparatus by embodiment of this invention. It is a principal part expanded sectional view which expands and shows the deceleration mechanism etc. in FIG. It is a longitudinal cross-sectional view shown in the state before assembling a hydraulic motor and a housing. It is a longitudinal cross-sectional view which shows the state which fastens a turning apparatus to the turning frame of an upper turning body using a rod-shaped tool.

Explanation of symbols

1 Hydraulic excavator 2 Lower traveling body (vehicle body)
3 Turning wheel 4 Upper turning body (car body)
4A slewing frame 5 working device 11 slewing device 12 hydraulic motor 13 motor case 13A motor housing portion 13B reduction gear housing portion 13C motor case side flange 14 bolt insertion hole 15 first ring gear 16 rotating shaft 17 housing 17A tube portion 17B housing side upper side Flange 17C Housing side lower flange 17D, 17E Bearing mounting portion 17F Outer peripheral surface 18 Screw hole 19 Bolt insertion hole 20 Second ring gear 21, 22 Planetary gear reduction mechanism (reduction mechanism)
21A, 22A Sun gear 21B, 22B Planetary gear 21C, 22C Carrier 21D Support pin 21E Bearing 23 Output shaft 24, 25 Bearing 26 Nut member 27 Pinion 28 Upper bolt (bolt)
29 Lower bolt 30 Building 31 Tool A Reducer housing space

Claims (4)

A motor case that houses a hydraulic motor therein, a cylindrical housing that is provided on the lower side of the motor case and attached to the vehicle body side, and that is attached to the upper side of the housing and defined by the housing and the motor case. Two or more speed reduction mechanisms provided in the reduction gear housing space, and an output shaft that is rotatably provided in the housing and outputs the rotation of the hydraulic motor decelerated by each speed reduction mechanism to the vehicle body side. In a construction machine turning device comprising:
The motor case is provided with a first ring gear that meshes with the first speed reduction mechanism among the speed reduction mechanisms, and the housing is provided with a second ring gear that meshes with the second speed reduction mechanism. A swing device for construction machinery.   The motor case includes a motor housing portion that houses the hydraulic motor, and a cylindrical reduction gear housing portion that is provided on the lower side of the motor housing portion and has the first ring gear formed on the inner peripheral side. The turning device for a construction machine according to claim 1.   The housing is provided on the inner peripheral side of the cylindrical portion, which is located below the second ring gear, and is provided on the inner peripheral side of the cylindrical portion in which the second ring gear is formed on the inner peripheral side, and is capable of rotating the output shaft. The turning device for a construction machine according to claim 1 or 2, comprising a bearing mounting portion to which a bearing to be supported is mounted.   A motor case side flange is provided on the lower side of the motor case, and a housing side upper flange that is abutted with the motor case side flange is provided on the upper side of the housing, the motor case side flange and the housing side upper flange, 4. The turning device for a construction machine according to claim 1, wherein the bolt is fastened using a bolt, and the bolt is disposed at a position in a radial direction substantially equal to the outer peripheral surface of the housing.

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