JP2011163513A - Rotary bearing, and construction machine using the rotary bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary bearing for thrust load, which can attain an extended life by minimizing the wear of a rolling element or rolling surface. <P>SOLUTION: The rotary bearing for thrust load includes: an inner ring; an outer ring located outside the inner ring; an annular rolling surface provided outside the inner ring; an annular rolling surface provided inside the outer ring; a plurality of rolling elements 24 rolling between the rolling surfaces; and a plurality of retainers 22 which rotatably receives each rolling element 24 and annularly aligns and retains each rolling element. The mutually opposed surfaces of the retainers 22 are engaged and connected with each other by aligning means 30, 31 which retain the retainers concentrically with a rotation center. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a thrust load slewing bearing and a construction machine using the slewing bearing, and more specifically, a thrust load having an annular horizontal rolling surface and a plurality of rolling elements disposed between the rolling surfaces. TECHNICAL FIELD The present invention relates to a slewing bearing and a construction machine using the slewing bearing.

  As a slewing bearing for thrust load, a plurality of annular horizontal rolling surfaces, a plurality of rolling elements disposed between the rolling surfaces, and a plurality of spacers that house each rolling element and maintain a space between the rolling elements. Some have a cage.

  In this type of slewing bearing, as a cage that can accommodate any of the slewing bearings having different shaft diameters, one opposing surface of a plurality of adjacent cages is formed as a projecting surface, and the other of the cages An opposing surface is formed in a concave surface, and one protruding opposing surface of the cage and the other concave opposing surface of the cage are slidably coupled (for example, Patent Document 1). reference.).

US Pat. No. 3,512,212

  Generally, a roller is applied as a rolling element of the above-described conventional slewing bearing. The roller rolls on an annular horizontal rolling surface, but the end length of the roller on the outer side of the slewing bearing and the end surface of the roller on the inner side of the slewing bearing differ in rolling length even at the same turning speed. The difference in angular velocity caused by the different rolling lengths of the rollers prompts the sliding movement of the roller end surfaces.

  When the roller end surface slips, the rolling element and the rolling surface are worn, and the contact between the rolling surface and the rolling element becomes unstable as the wear progresses. If such an unstable contact state between the rolling element and the rolling surface further progresses, the rolling element and the rolling surface may come into contact with each other, and eventually the slewing bearing may be damaged. is there.

  For the purpose of preventing the occurrence of such a sliding motion of the roller end surface, each roller is accommodated in a cage that holds the interval between the rollers. The cage is annularly arranged on the annular horizontal rolling surface, and the interval between the rollers is maintained by the thickness of the side wall of the opposing cage. In other words, adjacent cages are planned to come into sliding contact with each of the predetermined opposing surfaces, thereby preventing the sliding movement of the roller end surfaces.

  Therefore, for example, when the opposing surfaces of adjacent cages are greatly displaced in the radial direction, the interval between the rollers cannot be maintained, and the occurrence of the above-described slip is promoted.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a slewing bearing capable of reducing the amount of wear of a rolling element or a rolling surface as much as possible and prolonging the service life, and this The object is to provide a construction machine using a slewing bearing.

  In order to achieve the above object, the first invention includes an inner ring, an outer ring positioned outside the inner ring, an annular rolling surface provided outside the inner ring, and an annular ring provided inside the outer ring. A plurality of roller-like rolling elements that roll between the rolling surfaces, a plurality of cages that rotatably store the rolling elements, and that hold the rolling elements in an annular arrangement. In the thrust load slewing bearing, the opposing surfaces of the cages are engaged and connected by aligning means for holding the cages so as to be located concentrically with the pivot center. .

  Further, in a second aspect based on the first aspect, the aligning means includes a hemispherical convex portion provided in an intermediate portion in the width direction and the height direction on the other side surface in the annular direction of the cage, The cage is provided with a concave portion that is provided at an intermediate portion in the width direction and the height direction on one side surface in the annular direction of the cage and engages with a convex portion of an adjacent cage.

  Further, in a third invention according to the first invention, the alignment means includes a hemispherical convex portion provided in an intermediate portion in the width direction and the height direction on the other side surface in the annular direction of the cage, A concave portion that is provided in an intermediate portion in the width direction and the height direction on one side surface in the annular direction of the retainer and that engages with a convex portion of an adjacent retainer, and the retainer that reaches the concave portion and the upper surface of the retainer. It is provided on one side surface in the annular direction of the vessel, and is constituted by a groove having the same width and the same depth as the diameter of the concave portion.

  In a fourth aspect based on the first aspect, the aligning means is provided in the intermediate portion in the width direction on the other side surface in the annular direction of the cage from the lower surface to the upper surface of the cage. A columnar ridge and a ridge that is provided from the lower surface to the upper surface of the cage at an intermediate portion in the width direction on one side surface in the annular direction of the cage and engages with the ridge of the adjacent cage. It is characterized by comprising a groove.

  Further, a fifth invention is a construction machine characterized in that the slewing bearing according to the first to fourth inventions is installed in the slewing portion.

  According to the present invention, since the opposing portions of the cages in the slewing bearing are connected via the connecting portion having a centering function, the cage is maintained in alignment with the center of rotation of the slewing bearing. Can do. As a result, the amount of wear of the rolling elements and the rolling surfaces in the slewing bearing can be reduced as much as possible, and the life of the rolling elements can be extended.

  Furthermore, by applying the slewing bearing according to the present invention to the construction machine, the interval of the downtime of the construction machine accompanying the replacement of the slewing bearing can be extended, so that the productivity of the construction machine is improved.

It is a side view showing the whole construction work machine composition to which one embodiment of the slewing bearing of the present invention is applied. It is a vertical side surface which expands and shows the part of the turning apparatus of the construction work machine to which one Embodiment of the turning bearing of this invention shown in FIG. 1 is applied. It is a perspective view which expands further and shows the part of the turning apparatus of the construction work machine to which the turning bearing of this invention is applied. It is a top view which shows the rolling element and its holder | retainer in 1st embodiment of the turning bearing of this invention. It is a front view right view of the rolling element and its holder | retainer in 1st embodiment of the turning bearing of this invention shown in FIG. It is a front view left view of the rolling element and its holder | retainer in 1st embodiment of the turning bearing of this invention shown in FIG. It is a top view which shows the rolling element and its holder | retainer in 2nd embodiment of the turning bearing of this invention. It is a front view right view of the rolling element and its holder | retainer in 2nd embodiment of the turning bearing of this invention shown in FIG. It is a front view left view of the rolling element and its holder | retainer in 2nd embodiment of the turning bearing of this invention shown in FIG. It is a top view which shows the rolling element and its holder | retainer in 3rd embodiment of the turning bearing of this invention. It is a front view right view of the rolling element and its holder | retainer in 3rd embodiment of the turning bearing of this invention shown in FIG. It is a front view left view of the rolling element and its holder | retainer in 3rd embodiment of the slewing bearing of this invention shown in FIG.

Embodiments of a slewing bearing of the present invention and a construction machine to which the slewing bearing is applied will be described below with reference to the drawings.
FIG. 1 is a side view showing an embodiment of a construction machine to which a slewing bearing of the present invention is applied. FIG. 1 shows a crawler hydraulic excavator as an example of a large self-propelled construction work machine as an embodiment of a construction machine to which the slewing bearing of the present invention is applied.
In FIG. 1, reference numeral 1 denotes a crawler-type traveling body for allowing a self-propelled construction machine to travel, 2 is a revolving frame mounted on the traveling body 1 so as to be able to revolve, and 3 is installed above the revolving frame 2. A revolving body composed of various devices, 4 is a driver's cab provided on the front side of the revolving body 3, 5 is a prime mover room disposed at the center of the revolving body 3, and 6 is a counterweight installed at the rear of the revolving body 3. This counterweight is for balancing with the external force acting on the self-propelled construction work machine during work.

  7 is an articulated construction machine installed in the front part of the revolving structure 3 and includes a boom, an arm and a bucket, and performs excavation work of earth and sand. Reference numeral 8 denotes a swivel device for swiveling the swivel body 3, which is composed of a swivel bearing described later and a drive mechanism for driving the swivel bearing. In this example, the turning device 8 is disposed on the front side and the rear side of the vehicle body.

Next, a first embodiment of the above-described turning device 8 and the turning bearing according to the present invention installed in the turning device 8 will be described with reference to FIGS.
FIG. 2 is a longitudinal side view showing an enlarged part of a swing device of a construction machine to which the embodiment of the swing bearing of the present invention shown in FIG. 1 is applied, and FIG. 3 is a construction using the swing bearing of the present invention. FIG. 4 is a perspective view showing the swivel device portion of the working machine further enlarged, FIG. 4 is a plan view showing the rolling elements and their cages in the first embodiment of the swivel bearing of the present invention, and FIG. FIG. 6 is a front view right side view of the rolling element and its cage in the first embodiment of the slewing bearing of the present invention shown in FIG. 6, and FIG. 6 shows the rolling element in the first embodiment of the slewing bearing of the present invention shown in FIG. It is a front view left view of a moving body and its retainer.

  In FIG. 2, the swivel device 8 is composed of, for example, a planetary gear mechanism and the like, and is rotationally driven by a speed reducer 9 attached to the swivel frame 2 and a hydraulically driven swivel motor 10 attached to the top of the speed reducer 9. A drive mechanism including a drive pinion 11 is provided, and a swivel bearing 15 is included.

  Next, a detailed structure of the slewing bearing 15 and a peripheral structure thereof will be described with reference to FIGS. First, in FIG. 2, reference numeral 12 denotes an annular round cylinder provided on the upper portion of the traveling body 1, and 13 denotes an annular inner ring fixed to the upper surface of the circular cylinder 12 with a plurality of bolts. 13A is provided. Reference numeral 14 denotes an annular outer ring which is fixed to the lower surface of the revolving frame 2 which is a member on the revolving body 3 side by a plurality of bolts and is arranged so as to surround the outer side of the inner ring 13. The slewing bearing 15 is an installed slewing bearing that supports the slewing body 3 with respect to the round body 12 so as to be able to slew.

  As shown in FIG. 3, the inner ring 13 constituting the slewing bearing 15 includes an annular protrusion 16 that forms a rolling surface on the outer periphery. The outer ring 14 is provided with an annular recess 17 in which the protrusion 16 of the inner ring 13 is fitted on the inner periphery and forms a rolling surface. A plurality of cages 22 are annularly arranged between the upper rolling surface 18 of the outer ring 14 and the upper rolling surface 19 of the annular protrusion 16 in the inner ring 13. Roller-like rolling elements 24 are accommodated in the plurality of cages 22 so as to roll on the rolling surfaces 18 and 19. The slewing bearing 15 functions as a thrust bearing that receives a downward thrust force.

  A plurality of cages 23 are annularly arranged between the lower rolling surface 20 of the annular protrusion 16 in the inner ring 13 and the lower rolling surface 21 of the outer ring 14. Roller-like rolling elements 25 are housed in the plurality of cages 23 so as to roll on the rolling surfaces 20 and 21. The slewing bearing 15 has a function of receiving an upward thrust force.

  Further, between the rolling surface 26 on the outer peripheral surface of the protruding portion 16 of the inner ring 13 and the rolling surface 27 in the recessed portion of the outer ring, a roller-shaped rolling element 29 that rolls on the rolling surfaces 26 and 27, and The retainer 28 is disposed. This bearing has a function of receiving a radial arc.

Next, a detailed configuration of the cages 22 and 23 constituting the slewing bearing 15 that receives the thrust force described above will be described with reference to FIGS.
Since the cages 22 and 23 have a similar structure, the cage 22 will be described below as a representative.
The cage 22 is a substantially rectangular parallelepiped, and has a hollow box structure with the upper and lower surfaces open. A roller-shaped rolling element 24 is rotatably accommodated in the hollow portion of the cage 22. One side surface 22A (the right side surface in FIG. 4) of the cage 22 in the annular direction is formed by an arc-shaped convex surface, and the other side surface 22B (left side surface in FIG. 4) is formed by an arc-shaped concave surface.

  As shown in FIGS. 4 and 6, a hemispherical convex portion 30 is provided at the intermediate portion in the width direction and the height direction on the other side surface 22 </ b> B in the annular direction of the cage 22. Moreover, as shown in FIG.4 and FIG.5, the recessed part which the convex part 30 of the adjacent retainer 22 engages in the intermediate part of the width direction in the one side surface 22A of the cyclic | annular direction of the retainer 22, and a height direction. 31 is provided. Each retainer 22 is disposed annularly between the rolling surface 18 and the rolling surface 19 by engaging the convex portion 30 and the concave portion 31 at each end, and after assembling, the convex portion 30 and the concave portion 31. Is located on a concentric circle with the turning center S of the revolving structure 3. Thereby, the convex portion 30 and the concave portion 31 function as means for aligning the cage 22.

Next, the operation of the above-described first embodiment of the slewing bearing of the present invention will be described.
As described above, the thrust load slewing bearing 15 includes the cages 22, 23.
Are arranged annularly between the rolling surfaces 18 and 20 and the rolling surfaces 19 and 22 by engaging the convex portions 30 and the concave portions 31 at the respective ends with respect to the adjacent cages 22 and 23. After the assembly, the engaging position between the convex part 30 and the concave part 31 is located concentrically with the turning center of the turning body 3.

  For this reason, even if a radial force is applied to the slewing bearing 15, the radial displacement of the slewing body 3 does not occur between the cages 22 and 23, and the ideal annular arrangement is maintained. . That is, a line connecting the center points in the width direction (radial direction) of the rolling elements 24 and 25 is located concentrically with the turning center of the rotating body 3 and is the center axis of the rolling motion of the rolling elements 24 and 25. Since the extension line is located at the turning center point of the revolving structure 3, the sliding motion between the inner diameter side end faces and the outer shape side end faces of the roller-like rolling elements 24, 25 can be minimized. Thereby, the abrasion amount of the rolling elements 24 and 25 and the rolling surface in the slewing bearing 15 can be reduced as much as possible, and the lifetime can be extended.

  In particular, since the axial moment load and the radial moment load frequently act on the slewing bearing 15 used in the construction work machine due to the nature of the construction work machine, the cage inside the slewing bearing 15 is affected by an impact at the time of load application. 22 and 23, the radial force of the slewing bearing 15 partially acts, and several of the plurality of cages 22 and 23 move in the radial direction. In the present invention, Due to the engagement of the hemispherical convex portion 30 and the hemispherical concave portion 31 provided on the opposing surfaces of the annularly arranged cages 22 and 23, the rolling elements 24 and 25 and the cages 22 and 23 thereof are arranged in the radial direction. The movement is suppressed, and an aligned circulation motion with the turning body 3 as the turning center is performed. For this reason, the wear between the rolling elements 24 and 25 and the rolling surfaces 18 to 21 can be reduced as compared with the conventional one.

  According to the above-described embodiment of the present invention, since the engaging means of the convex portion 30 and the concave portion 31 are provided on the respective opposing surfaces of the cages 22 and 23 constituting the slewing bearing 15, the cage 22, 23 alignment function is improved. As a result, the amount of wear between the rolling elements 24 and 25 and the rolling surfaces 18 to 21 in the slewing bearing 15 can be reduced as much as possible, and the life can be extended.

  FIGS. 7 to 9 show a second embodiment of the slewing bearing of the present invention, and FIG. 7 is a plan view showing the rolling element and its cage in the second embodiment of the slewing bearing of the present invention. 8 is a front view right side view of the rolling element and its cage in the second embodiment of the slewing bearing of the present invention shown in FIG. 7, and FIG. 9 is a second side view of the slewing bearing of the present invention shown in FIG. It is a front view left view of a rolling element and its cage in an embodiment. In these drawings, the same reference numerals as those shown in FIGS. 4 to 6 are the same parts, and detailed description thereof will be omitted.

  In this embodiment, as in the first embodiment described above, as shown in FIG. 8, adjacent to the intermediate portion in the width direction and the height direction on one side surface 22A in the annular direction of the retainer 22 A hemispherical recess 31 that engages with the convex portion 30 of the retainer 22 is provided, and the hemispherical recess 31 and one side 22A in the annular direction of the retainer 22 reaching the upper surface of the retainer 22 A groove 32 having the same width and the same depth as the diameter is provided.

  According to the second embodiment of the present invention, the same effect as that of the first embodiment can be obtained. In the first embodiment described above, when the cage 22 is arranged in an annular shape, attention must be paid to the engagement of the hemispherical uneven portions 31 and 30, but in the second embodiment, Since the convex portion 30 can be fitted into the groove 32 from above, the assembling workability is improved.

  10 to 12 show a third embodiment of the slewing bearing of the present invention. FIG. 10 is a plan view showing a rolling element and its cage in the third embodiment of the slewing bearing of the present invention. 11 is a front view right side view of a rolling element and its cage in the third embodiment of the slewing bearing of the present invention shown in FIG. 10, and FIG. 12 is a third side view of the slewing bearing of the present invention shown in FIG. It is a front view left view of a rolling element and its cage in an embodiment. In these drawings, the same reference numerals as those shown in FIGS. 4 to 6 are the same parts, and detailed description thereof will be omitted.

  In this embodiment, as shown in FIGS. 10 and 12, a semi-cylindrical ridge 33 is provided on the upper surface from the lower surface of the cage 22 at the intermediate portion in the width direction of the other side surface 22 </ b> B in the annular direction of the cage 22. 10 and FIG. 11, the groove in which the convex strip 33 of the adjacent cage 22 engages with the intermediate portion in the width direction of the one side surface 22A in the annular direction of the cage 22. 34 is provided from the lower surface to the upper surface of the cage 22.

  According to this embodiment, the same effect as that of the first embodiment described above can be obtained. Further, according to this embodiment, the assembly workability is improved as in the second embodiment described above, and when the cage is manufactured, the mold can be pulled upward after forming the shape. Since this is possible, the productivity of the cage is improved.

DESCRIPTION OF SYMBOLS 1 Traveling body 2 Swing frame 3 Swing body 7 Working machine 8 Swivel device 9 Reduction gear 10 Drive pinion 11 Swing motor 12 Round body 13 Inner ring 14 Outer ring 15 Slewing bearing 22 Retainer 23 Retainer 24 Rolling element 25 Rolling element 30 Convex part ( Aligning means)
31 Concavity (alignment means)

Claims (5)

Rolls between the inner ring, an outer ring located outside the inner ring, an annular rolling surface provided outside the inner ring, an annular rolling surface provided inside the outer ring, and the rolling surface. In a thrust load slewing bearing comprising a plurality of roller-shaped rolling elements, and a plurality of cages that rotatably accommodates the rolling elements and holds the rolling elements in an annular shape,
The slewing bearing characterized in that the opposing surfaces of the cages are engaged and connected by aligning means for holding the cages so as to be located concentrically with the pivot center. The slewing bearing according to claim 1,
The aligning means includes a hemispherical convex portion provided in a width direction on the other side surface in the annular direction of the cage and a middle portion in the height direction, a width direction on one side surface in the annular direction of the cage, and A slewing bearing comprising: a concave portion provided at an intermediate portion in the height direction and engaged with a convex portion of an adjacent cage. The slewing bearing according to claim 1,
The aligning means includes a hemispherical convex portion provided in a width direction on the other side surface in the annular direction of the cage and a middle portion in the height direction, a width direction on one side surface in the annular direction of the cage, and A concave portion provided at an intermediate portion in the height direction and engaged with a convex portion of an adjacent cage; and provided on one side surface in the annular direction of the cage that reaches the upper surface of the concave portion and the cage; A slewing bearing comprising a groove having the same width and the same depth as the diameter. The slewing bearing according to claim 1,
The aligning means includes a semi-cylindrical ridge provided from the lower surface to the upper surface of the retainer at the widthwise intermediate portion on the other side surface in the annular direction of the retainer, and the annular direction of the retainer. On the other hand, a slewing bearing comprising: a groove provided in a middle portion in the width direction on the side surface from a lower surface to an upper surface of the cage, and engaging with a convex row of the adjacent cage. A construction machine, wherein the slewing bearing according to any one of claims 1 to 4 is installed in a slewing part.

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