JP2006328898A - Ball race for construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To standardize a ball race for using it in different models of construction machine, and improve the assembling efficiency of the ball race. <P>SOLUTION: The ball race has an outer race 21 which is fitted rotatably to the outer periphery of an inner race 17, which is fixed to the lower running body side, via a roller, and is fastened to the lower face of a base plate of a swiveling frame of an upper swiveling body by tightening a plurality of bolts. The outer race 21 has a plurality of bolt insertion holes 26, through which the bolts are inserted, and given bolt insertion holes out of the plurality of bolt insertion holes are formed into slot holes 26a each having a given length along the circumference of the outer race 21. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a ball race for construction machinery, and in particular, in a ball race for construction machinery such as a hydraulic excavator, the ball race for construction machinery capable of sharing the ball race among different types of construction machinery. It is about.

  As a conventional technique related to a ball race for construction machinery, for example, the following swing frame for construction machinery is known. In this prior art, an upper turning body is mounted on a lower traveling body through a turning wheel so as to be turnable. The turning wheel is fixed to the circular body of the track frame in the lower traveling body by using a plurality of bolts, and an inner ring on which an inner tooth with which a pinion for turning driving force is engaged is formed on the inner peripheral side, and the inner ring It consists of an outer ring that is rotatably provided on the outer peripheral side through a steel ball as a rolling element, and the outer ring is fixed to the lower surface of the bottom plate constituting the turning frame in the upper turning body by using a number of bolts. Yes. In the outer ring, a large number of bolt insertion holes corresponding to the large number of bolts are formed on the same circumference, and the bolts inserted through the bolt insertion holes are screwed to the bottom plate of the turning frame.

  On the other hand, left and right vertical plates are erected on the upper surface of the bottom plate of the revolving frame so as to extend forward and rearward and whose front end side is a boom mounting bracket. Further, in order to increase the bending strength of the boom mounting bracket, a reinforcing plate inclined rearward is joined between the left and right boom mounting brackets, and the lower side of the reinforcing plate is joined to the upper surface of the bottom plate by welding. ing. Further, left and right cylinder mounting brackets are erected at a position on the front side of the reinforcing plate.

Thus, on the upper surface of the bottom plate of the revolving frame, left and right vertical plates and left and right cylinder mounting brackets serving as boom mounting brackets are erected, and further, the lower side of the reinforcing plate for reinforcing the boom mounting bracket is It is joined. For this reason, the numerous bolts for attaching the outer ring to the lower surface of the bottom plate in the turning frame are tightened avoiding the positions where the left and right vertical plates are erected on the upper surface. Then, the pitch of the bolt mounting holes (bolt screwing holes) in the bottom plate, in other words, the pitch of the bolt insertion holes in the outer ring is not uniform (see, for example, Patent Document 1).
JP 2001-317085 A (pages 3 and 4, FIGS. 1 to 6).

  In the prior art described in Patent Document 1, a large number of bolts for attaching the outer ring (outer race) of the swivel wheel (ball race) to the lower surface of the bottom plate (base plate) in the swivel frame are provided on the upper surface as a boom mounting bracket. Since it is tightened so as to avoid the position where the right vertical plate or the like is erected, the pitch of the bolt insertion holes in the outer ring is not uniform at these positions.

  Therefore, if you want to use swirling wheels with the same outer diameter between other models of construction machinery, if the vertical position of the vertical plate on the bottom plate upper surface in the swivel frame is different, to avoid these positions, In order to set the tightening position of the bolts, it becomes necessary to separately manufacture turning wheels in which the positions of the bolt insertion holes in the outer ring are partially different.

  In this case, it may be possible to make the swirl wheel common to other models of the construction machine by additionally drilling appropriate discard holes in the outer ring. However, if a discard hole is additionally drilled in the outer ring, when the outer ring is attached to the lower surface of the bottom plate of the revolving frame, an erroneous recognition of a suitable bolt insertion hole occurs, and the assemblability is lowered.

  Thus, there is a technical problem to be solved in order to make the ball race common among different types of construction machines and to improve the assemblability, and the present invention aims to solve this problem.

  The present invention has been proposed in order to achieve the above-mentioned object, and the invention according to claim 1 has an upper revolving body mounted on a lower traveling body through a ball race so as to be able to swivel, and the ball The race is formed with an internal gear that meshes with a pinion for transmitting the turning driving force at the inner peripheral portion, and an inner race that is fixed to the track frame side in the lower traveling body, and is rolled to the outer peripheral portion of the inner race. A ball race for a construction machine, comprising: an outer race that is rotatably mounted via a child and is attached to a lower surface of a base plate of a revolving frame in the upper revolving structure by tightening a plurality of bolts. Among a plurality of bolt insertion holes through which a plurality of bolts are inserted, a required bolt insertion hole is required in the circumferential direction of the outer race. It is to provide a construction machine for a ball race which is formed in a long hole with.

  According to this configuration, it is desirable that the bolt pitches of the plurality of bolts for attaching the outer race to the lower surface of the base plate of the revolving frame are uniform over the entire circumference. However, on the upper surface of the base plate, a web plate or the like constituting a revolving frame such as a left and a right vertical plate that is a mounting bracket of the work machine is attached. For this reason, the plurality of bolts avoid the positions where the web plate or the like is attached to the upper surface, and the bolt pitch is non-uniform at these positions. And when the model of a construction machine differs, the attachment position of a web board etc. to a baseplate upper surface often changes little by little. For this reason, if the model of a construction machine differs, bolt pitch will also differ. Therefore, among the plurality of bolt insertion holes drilled in the outer race, the required bolt insertion hole is a long hole having a required length in the circumferential direction of the outer race, so that the model of the construction machine is different. A partial bolt pitch difference is absorbed by the long hole, and the bolt pitch difference does not exist in the outer race having the long hole.

  According to a second aspect of the present invention, in the construction machine ball race, the formation of the elongated hole in the outer race is performed on the outer race of the same outer diameter in a stage as an assembly part before being assembled to the construction machine. provide.

  According to this configuration, even if the construction machine model is different and the mounting position of the web plate etc. on the upper surface of the base plate is different, and there is a difference in the bolt pitch between different models, For the outer race of the same outer diameter at the stage, the required bolt insertion hole is a long hole having a required length in the circumferential direction of the outer race, so that the ball race as an assembling part is the different model It is possible to absorb the difference in the bolt pitch between them, and to apply the ball race composed of the outer race of the long hole in common to construction machines between different models.

  In the first aspect of the invention, among the plurality of bolt insertion holes through which the plurality of bolts in the outer race are inserted, the required bolt insertion hole is formed as a long hole having a required length in the circumferential direction of the outer race. The difference in the bolt pitch due to the difference in the construction machine model is absorbed in the outer race long hole, and the outer race having the long hole no longer has the bolt pitch difference. Can be properly attached to the bottom surface of the base plate. Therefore, the ball race can be shared among different models of construction machines. Further, as compared with the case where a discard hole is additionally drilled in the outer race, there is an advantage that an erroneous recognition of an appropriate bolt insertion hole is eliminated and the assemblability can be improved.

  In the invention described in claim 2, since the formation of the long hole in the outer race is performed on the outer race having the same outer diameter in the stage as an assembly part before being assembled to the construction machine, the construction machine type is different. Even if there is a partial difference in bolt pitch, the ball race as an assembly part can absorb the difference in bolt pitch between different models, and it consists of an outer race with a long hole. Parts can be used in common among different models of construction machines. In addition, it is possible to provide compatibility with an old ball race part having the same outer diameter, and the ball race part including the outer race of the long hole is applied to a construction machine that requires the old ball race part. There is an advantage that you can.

  For the purpose of making the ball race common between different models of construction machines and improving the assemblability, the ball race has an upper turning body mounted on the lower traveling body so as to be able to turn through the ball race. An internal gear is formed on the inner peripheral portion, and a pinion for transmitting the turning driving force is engaged, and an inner race fixed to the track frame side in the lower traveling body, and a rolling element on the outer peripheral portion of the inner race. And a plurality of outer races mounted on the lower surface of the base plate of the revolving frame of the upper revolving body by tightening a plurality of bolts. Of the plurality of bolt insertion holes through which the bolt is inserted, the required bolt insertion hole is the circle of the outer race. Formed into a long hole with the required length in the direction, and the formation of the long hole is realized by applying it to the outer race of the same outer diameter in the stage as an assembly part before assembling to the construction machine did.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, the construction of the construction machine ball race according to the present embodiment will be described. The present embodiment is applied to a hydraulic excavator as a construction machine. FIG. 1 is a side view of the hydraulic excavator, FIG. 2 is an enlarged longitudinal sectional view of a ball race portion of the hydraulic excavator, and FIG. 3 is a plan view of the ball race as viewed from line AA in FIG.

  In the excavator 1, a round body 4 is provided at the center of the track frame 3 in the lower traveling body 2. A ball race (swivel wheel) 5 is attached to the upper end side of the round body 4, and an upper swing body 6 is mounted on the lower traveling body 2 via the ball race 5 so as to be able to swing.

  A cab 8 is provided on one front side of the revolving frame 7 in the upper revolving structure 6. A boom mounting bracket 9 is formed on the upper side of the front center portion of the revolving frame 7, and a cylinder mounting bracket 10 is formed on the lower front side of the boom mounting bracket 9. The boom mounting bracket 9 and the cylinder mounting bracket 10 are formed as a pair of left and right, respectively, in a direction perpendicular to the paper surface of FIG.

A boom 11 is pin-coupled to the boom mounting bracket 9 so as to be able to move up and down. A bucket 13 is attached to the tip of the arm 12. A boom cylinder 11 a, whose proximal end is pin-coupled to the cylinder mounting bracket 10, is attached to the boom 11, and the arm cylinder 12 a is attached between the boom 11 and the arm 12. A bucket cylinder 13 a is attached between the arm 12 and the bucket 13.

  An engine 14 is mounted on the rear portion of the revolving frame 7, and the engine 14 is covered with a house cover 15.

  As shown in FIG. 2, the ball race 5 has an internal gear 17a formed on the inner periphery thereof and is fixed to the round body 4 of the track frame 3 in the lower traveling body 2 by using a plurality of bolts 16,. The inner race (inner ring) 17 and the inner race 17 are rotatably mounted on the outer periphery of the inner race 17 via steel balls 18 as rolling elements, and a plurality of lower surfaces of the base plate (bottom plate) 19 of the revolving frame 7 It comprises an outer race (outer ring) 21 attached by tightening bolts 20. The inner race 17 and the outer race 21 are arranged so as to be concentric with the turning center 6 a of the upper turning body 6.

  As shown in FIG. 3 described later, the outer race 21 has a plurality of bolt insertion holes corresponding to the plurality of bolts 20,... On the same circumference, and the bolt insertion holes are inserted through the bolt insertion holes. Each bolt 20 is screwed to the lower surface of the base plate 19.

  On the base plate 19 just behind the turning center 6 a of the upper turning body 6, a turning unit 22 is attached, and a pinion 23 is provided so as to protrude from the lower surface of the turning unit 22. The turning unit 22 includes a turning motor (not shown) and a speed reducer (not shown) that decelerates the rotation of the turning motor and rotates the pinion 23 at low speed and high torque. . The pinion 23 is meshed with an internal gear 17 a formed on the inner peripheral portion of the inner race 17.

  On the other hand, a vertical plate 24 is erected on the upper surface of the base plate 19 so as to extend forward and rearward and whose front end side becomes the boom mounting bracket 9. The vertical plate 24 is formed with a left and right pair in a direction perpendicular to the paper surface of FIG. A reinforcing plate 25 inclined rearward is joined between the left and right boom mounting brackets 9, and the lower side of the reinforcing plate 25 is joined to the upper surface of the base plate 19 by welding. Further, the left and right cylinder mounting brackets 10 are provided upright at a position on the front side of the reinforcing plate.

  Thus, the left and right vertical plates 24 and the left and right cylinder mounting brackets 10 are erected on the upper surface of the base plate 19, and the lower side of the reinforcing plate 25 is joined. Therefore, the plurality of bolts 20,... For attaching the outer race 21 to the lower surface of the base plate 19 are provided with a web plate or the like constituting the revolving frame 7 such as the left and right vertical plates 24 on the upper surface. Since these positions are screwed, the pitch of the bolt mounting holes (bolt screwing holes) in the base plate 19, in other words, the pitch of the bolt insertion holes in the outer race 21 is not uniform at these positions.

  By the way, if the type of the hydraulic excavator 1 as a construction machine is different, the standing position of the web plate or the like on the upper surface of the base plate 19 often differs little by little. Therefore, when the models of the hydraulic excavator 1 are different and the standing positions of the web plate or the like are different, the pitch of the bolt insertion holes for avoiding these standing positions is further different.

  On the other hand, in the present embodiment, as shown in FIG. 3, among the plurality of bolt insertion holes 26 in the outer race 21, the required bolt insertion hole is a length having a required length in the circumferential direction of the outer race 21. By forming in the hole 26a, the pitch of the bolt insertion hole 26 due to the difference in the standing position of the web plate or the like, that is, the difference in the bolt pitch is absorbed by the long hole 26a, so that the ball race 5 is different between different models of the hydraulic excavator 1. It can be applied in common.

  The formation of the long hole 26a in the outer race 21 is performed on the outer race 21 having the same outer diameter in the stage as an assembly part before being assembled to the hydraulic excavator 1, and when the hydraulic excavator 1 is assembled, the hydraulic excavator 1 is assembled. Even if the model 1 is different, it can be used as a common assembly part.

  Next, the setting and operation of the long holes in the construction machine ball race configured as described above will be described with reference to FIGS. 4 (a), 4 (b), and 4 (c). 4 (a) and FIG. 4 (b) partially show the outer race 21a and the outer race 21b having the same outer diameter mounted on the hydraulic excavators 1 of different models.

Due to the different models of the hydraulic excavator 1, the bolt pitch of the bolt insertion holes 26 in the outer race 21 a corresponding to the standing position is P ₁ due to the difference in the standing position of the web plate on the upper surface of the base plate 19. bolt pitch of the bolt holes 26 in the outer race 21b is in the P _2.

In contrast, in the outer race 21c of this embodiment, the bolt insertion holes of a required portion corresponding to the upright position, such as the web plate, the long hole 26a as including said bolt pitch P ₁ and the bolt pitch P ₂ By setting the bolt pitch, the difference between the bolt pitches P ₁ and P ₂ is absorbed by the long hole 26a, and the ball race provided with the outer race 21c is commonly attached to both hydraulic excavators 1 of different models. It becomes possible.

  In each hydraulic excavator 1 in which the common ball race 5 is properly mounted, the inner race 17 is driven at low speed and high torque by the pinion 23 via the internal gear 17a, so that the turning frame 7 Turns around the turning center 6a together with the outer race 21, and the turning operation of the upper turning body 6 is performed.

  As described above, in the ball race for construction machinery according to the present embodiment, the ball race can be shared between different models of the hydraulic excavator 1 as the construction machinery.

  Compared with a case where a discard hole is additionally drilled in the outer race, erroneous recognition of an appropriate bolt insertion hole is eliminated, and assemblability can be improved.

  In addition, compatibility with the old ball race component can be provided, and the ball race 5 component including the outer race 21 having the long hole 26a can be applied to the hydraulic excavator 1 that requires the old ball race component. it can.

  The present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

The figure shows a construction machine ball race according to an embodiment of the present invention.
The side view of a hydraulic excavator. FIG. 2 is an enlarged longitudinal sectional view of a ball race portion in FIG. 1. The top view of the ball race seen from the AA line in FIG. The figure for demonstrating the setting of the long hole to an outer race.

Explanation of symbols

1 Excavator (construction machine)
2 Lower traveling body 3 Track frame 5 Ball race 6 Upper turning body 7 Turning frame 17 Inner race 17a Internal gear 18 Steel ball (roller)
19 Base plate 20 Bolt 21 Outer race 23 Pinion 26 Bolt insertion hole 26a Long hole

Claims (2)

An upper revolving body is mounted on the lower traveling body so as to be able to swivel via a ball race, and the ball race has an internal gear with which a pinion for swivel driving force transmission is engaged with an inner peripheral portion. An inner race fixed to the track frame side in the lower traveling body, and a plurality of bolts mounted on the outer periphery of the inner race via a rotator and on the lower surface of the base plate of the turning frame in the upper swing body In a ball race for construction machinery comprising an outer race attached by tightening
Of the plurality of bolt insertion holes through which the plurality of bolts in the outer race are inserted, the required bolt insertion hole is formed as a long hole having a required length in the circumferential direction of the outer race. Ball race for construction machinery. The construction machine ball according to claim 1, wherein the formation of the elongated hole in the outer race is performed on the outer race having the same outer diameter in a stage as an assembly part before being assembled to the construction machine. race.

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