JP2003268803A - Slewing device for construction machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a slewing device for construction machinery capable of making a backlash generated between an internal gear and a pinion smaller than conventional devices. <P>SOLUTION: In the slewing device for construction machinery having an inner ring 3 having the internal gear 3a and being fixed on an understructure 1 side, a rotatable outer ring 4 fixed on the revolving frame 2 side, the pinion 6 engaged with the internal gear 3a and a pinion driving device 7 and installing the pinion driving device 7 on the revolving frame 2 side by a bolt 23, the slewing device is constituted so that a knock pin 20 with an eccentric section 20b made eccentric to a head section 20a and a rotational axial center and a non-eccentric section 20c not made eccentric is mounted and a distance between the center of the internal gear 3a and the center of the pinion 6 can be changed by inserting the eccentric section 20b and non-eccentric section 20c of the knock pin into the pin inserting hole 21 of the flange 7a of the pinion driving device 7 and the pin inserting hole 22 of the revolving frame 2 respectively and rotating and operating the head section 20a. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inner wheel having an internal gear and fixed to a base and an outer wheel fixed to a turning frame and capable of turning around the inner wheel. The present invention relates to a turning device for a construction machine including a pinion that meshes with an internal gear of an inner ring and a pinion driving device that rotationally drives the pinion. 2. Description of the Related Art A turning device of a construction machine is a device for turning an upper revolving structure including a revolving frame and various devices installed on an upper portion thereof with respect to a base such as a lower traveling structure.
An inner ring having an inner gear and fixed to the base side, an outer ring fixed to the turning frame side and capable of turning around the inner ring, a pinion meshing with the inner gear of the inner ring, and a pinion for rotating the pinion And a driving device. This pinion drive device is a device serving as a drive source for turning the upper turning body with respect to the base, and usually includes a motor such as a hydraulic motor and a speed reducer that reduces the rotation of the motor and transmits the rotation to the pinion. And is installed on the revolving frame side. A turning device of a construction machine engages a pinion on a turning frame side with an internal gear of an inner ring on a lower traveling body side so that a turning frame constituting an upper turning body can be turned with respect to a base. Therefore, it is necessary to accurately mesh the pinion and the internal gear so that the upper swing body does not rattle during the swing. The present invention has been created to meet such a demand. Therefore, in order to be able to easily understand the features of a swing machine for a construction machine according to the present invention described below,
The technical contents of a swing device of a construction machine which has been conventionally implemented by the applicant will be outlined with reference to FIGS. FIG. 6 is a vertical sectional view of a main part of a turning device of a construction machine according to a conventional example.
FIG. 8 is an enlarged view of a part shown in FIG. 6, FIG. 8 is an enlarged perspective view of a knock pin in the turning device of the construction machine shown in FIG. 6, and FIG.
It is a bottom view of the knock pin of FIG. In these figures, reference numeral 1 denotes a base for installing an upper revolving unit, a lower traveling unit of a self-propelled construction machine traveling by a crawler, a wheel, or the like, and 2 denotes a lower traveling unit 1 serving as a base of the upper revolving unit. A revolving frame 3 which is installed so as to be revolvable upward, 3 is an annular inner ring fixed to the lower traveling body 1 side, 3a is an internal gear (ring gear) provided on the inner peripheral portion of the inner ring 3 and 4 is an inner ring 3 An annular outer ring 5 fixed to the turning frame 2 side so as to surround concentrically and capable of turning around the inner ring 3 is housed in an annular space between the outer peripheral surface of the inner ring 3 and the inner peripheral surface of the outer ring 4. A rolling element 6 that acts as a bearing, and a pinion 6 meshes with the internal gear 3a of the inner ring 3;
Reference numeral 7 denotes a pinion driving device that drives the pinion 6 to rotate. [0005] Various devices such as a driver's cab, an engine room, and a counterweight (not shown) are installed on the revolving frame 1. The upper revolving unit is a general term for an assembly of these devices and the revolving frame 2. Things. On the front side of the revolving frame 2, for example, the front of a boom, an arm, a bucket and the like in a hydraulic shovel is installed so as to be able to move up and down. The device provided with the inner wheel 3 and the outer wheel 4 is called a swing wheel, and is provided between the lower traveling structure 1 and the swing frame 2 to support the front and upper swing structure on the swing frame 2 so as to be able to swing. Work. Pinion drive 7
Comprises a hydraulic motor not shown in the figure, and a speed reducer including a planetary gear mechanism disposed below the hydraulic motor to reduce the rotation thereof, and connects the output shaft of the speed reducer to the pinion. . These hydraulic motors and reduction gears are housed in a housing and mounted on the revolving frame 2 with bolts. The turning device of the construction machine includes a pinion 6 and an inner wheel 3 fixed to the lower traveling body 1, an outer wheel 4 fixed to the turning frame 2, and an inner gear 3 a of the inner wheel 3. Pinion drive 7 installed on the side
The rotation frame 2 can be turned by rotating the pinion 6 with the pinion driving device 7. That is, when the pinion 6 is rotationally driven, the pinion 6 rotates while meshing with the internal gear 3a of the inner race 3 on the lower traveling body 1 side, and the lower traveling body 1 itself is in contact with the ground and can rotate. Therefore, the turning frame 2 turns relative to the undercarriage 1 and turns. As described above, the turning device of the construction machine rotates the turning frame 2 by engaging the pinion 6 with the internal gear 3a, so that a backlash (internal gear) between the internal gear 3a and the pinion 6 is formed. If the play or gap between the teeth 3a and the pinion 6 meshes with each other is excessive, the front installed on the revolving frame 2 swings greatly during the work, thereby lowering the work accuracy. For example, when the backlash of the hydraulic excavator becomes excessive, the swing frame 2 rattles when performing excavation work with the bucket, and the rattle is transmitted to the bucket through the boom or the arm. It is amplified and reduces the excavation work accuracy. In order to cope with such a problem, in the conventional turning device for construction machines, the pinion driving device 7 is connected to the turning frame 2.
In this case, a method of mounting with high accuracy by positioning with a dowel pin 10 has been adopted. This conventional method will be described. In the conventional turning device for construction machines, a pin insertion hole 11 and a pin insertion hole, into which the knock pin 10 can be tightly inserted, into the flange 7a and the turning frame 2 of the pinion drive device 7, respectively. 12 are drilled. Further, since the pinion driving device 7 is attached to the turning frame 2 with the bolts 13, the flange 7 a of the pinion driving device 7 includes
A plurality of bolt insertion holes 14 slightly larger in diameter than the bolt 13 are formed in the circumferential direction, and a plurality of screw holes 15 are formed in the revolving frame 2 corresponding to the bolt insertion holes 14. . In the conventional method, first, the bolts 13 are respectively inserted into the respective bolt holes 14 of the flange 7a of the pinion driving device 7 and loosely screwed into the respective screw holes 15 of the revolving frame 2, thereby forming the pinion driving device. 7 is temporarily fixed with bolts 13. Next, when the knock pin 10 is completely fitted into the pin fitting hole 11 of the flange 7 a and the pin fitting hole 12 of the turning frame 2, the pinion driving device 7 can be positioned at a predetermined position of the turning frame 2. According to such a method, the pinion drive device 7 can be accurately positioned at the correct position of the turning frame 2 by setting the drilling positions of the pin insertion holes 11 and 12 at appropriate positions. After the pinion driving device 7 is positioned in this manner, when the bolt 13 is firmly tightened to fix the position of the pinion driving device 7 to the revolving frame 2, the pinion 6 can be accurately positioned at a predetermined position, resulting in excessive backlash. Can be suppressed. [0010] In this conventional turning device for construction machinery, by employing such a method, the backlash between the internal gear 3a and the pinion 6 can be reduced within a predetermined tolerance range. (Within an allowable value range), but a turning device having a large backlash or a turning device with a small backlash is manufactured within the range of the tolerance. That is, when designing the teeth of the internal gear 3a and the pinion 6, it is possible to prevent the internal gear 3a and the pinion 6 from fitting too tightly to prevent the pinion 6 from rotating, or inevitably occur during manufacturing. In order to absorb the dimensional error of the internal gear 3a and the pinion 6, a method of designing a backlash called "single backlash" for thinning the teeth in advance has been adopted. Due to the degree of finishing of the revolving frame 2 and the manufacturing error caused by quenching of the internal gear 3a, a non-negligible variation occurs in the amount of backlash within the tolerance. In particular, recently, it has been required to improve the working accuracy of the construction machine and improve the usability by reducing the backlash as much as possible so as not to become unnecessarily large. The device cannot adequately meet such demands. SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a technical problem of the present invention is to provide a turning device for a construction machine capable of reducing backlash between an internal gear and a pinion as compared with the prior art. To provide. In order to achieve the above technical object, the present invention provides an inner ring having an inner gear at an inner peripheral portion and fixed to a base, and a swivel surrounding the inner ring. An outer ring fixed to the frame side and capable of turning around the inner ring, a pinion meshing with the inner gear of the inner ring, and a pinion drive device for rotating this pinion are provided, and the pinion drive device is attached to the turning frame side with bolts and installed. In a turning device of a construction machine, a head part capable of turning operation, a shaft part having an eccentric part eccentric with respect to the rotation axis and a non-eccentric part not eccentric with respect to the rotation axis are formed. A knock pin having a pin is provided, and a shaft portion of the knock pin is inserted into each pin insertion hole formed in each of the member on the pinion drive device side and the member on the turning frame side to rotate the head of the knock pin. Thus, the distance between the center of the internal gear of the inner ring and the center of the pinion can be changed. When the pinion drive device is mounted on the turning frame, the pinion drive device is moved to the turning frame side so that the pinion drive device can be displaced relative to the turning frame. Temporarily fix with bolts. Further, the shaft of the knock pin is fitted into each of the pin fitting holes formed in the member on the pinion drive device side and the member on the turning frame side. Next, when the head of the knock pin is rotated, the eccentric portion of the shaft of the knock pin is rotated to displace the pinion drive device with respect to the turning frame, so that the pinion is also displaced with the displacement of the pinion drive device. The distance between the internal gear of the inner ring and the center of the pinion can be changed. Therefore, by performing such an operation, it is possible to adjust the distance between the center of the internal gear and the pinion so as to reduce the backlash between the internal gear and the pinion. After reducing the backlash as much as possible, further tighten the temporarily fixed bolts,
The pinion driving device is permanently fixed to the turning frame to fix the position. According to the turning device for a construction machine of the present invention, the backlash generated between the internal gear and the pinion can be reduced as compared with the related art by attaching the pinion drive device to the turning frame through the above operations. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. 1 to 5 showing concrete examples showing how the present invention is actually embodied. To reveal. FIG. 1 is a vertical sectional view of a main part of a turning device of a construction machine according to an embodiment of the present invention, FIG. 2 is an enlarged view of a portion A of FIG. 1, and FIG. 3 is a construction machine of FIG. 4 is an enlarged perspective view of the knock pin in the turning device of FIG. 3, FIG. 4 is a bottom view of the knock pin of FIG. 3, and FIG. 5 is a plan view showing a modification of the knock pin of FIG. In these figures, the parts denoted by the same reference numerals as those in FIGS. 6 to 9 described above represent the same parts as those in FIGS. 6 to 9 and will not be described in detail. The turning device for a construction machine according to this embodiment has an annular inner ring 3 having an inner gear 3a on the inner periphery and fixed to the lower traveling body 1 side, and a turning frame surrounding the inner ring 3. An outer ring 4 fixed to the inner side 2 and capable of turning around the inner ring 3 via a rolling element 5;
a, and a pinion drive device 7 having a hydraulic motor and a speed reducer, which rotationally drives the pinion 6. A flange 7 a of a housing of the pinion drive device 7 is provided.
6 to 9 is attached to the turning frame 2 by bolts, and the basic structure is the same as that of the turning apparatus for a construction machine according to the related art shown in FIGS. Further, the internal gear 3a of the inner ring 3 and the pinion 6
Between them, the above-mentioned single backlash is provided similarly to the turning device of the construction machine according to the conventional example. Therefore, the technical contents characteristic of the turning device for a construction machine according to this embodiment will be described. 1 to 5, reference numeral 20 denotes a knock pin according to the present invention, 20a denotes a head of the knock pin 20 which can be rotated, and 20b denotes a shaft of the knock pin 20 and a rotation axis of the knock pin 20. An eccentric portion which is eccentric with respect to 20y, 20c is a non-eccentric portion which forms the shaft portion of the knock pin 20 and is not eccentric with respect to the rotation axis 20y of the knock pin 20, and 21 is an eccentric portion which is formed on the flange 7a of the pinion drive device 7. Reference numeral 22 denotes a pin insertion hole that allows the close insertion of the pin 20b, and reference numeral 22 denotes a pin insertion hole that is formed in the revolving frame 2 and that allows the non-eccentric portion 20c to be inserted closely. The knock pin 20 is, in the example shown here, 6
It is formed of a square head 20a and a shaft portion including an eccentric portion 20b and a non-eccentric portion 20c. The head 20a of the knock pin 20 is formed so that the tool can be turned around a turning axis 20y of the knock pin 20 by a tool. The eccentric portion 20b of the knock pin 20 is connected to the rotation axis 2 of the knock pin 20.
Eccentric shaft center 20 at a position shifted by eccentricity b from 0y
It has a cylindrical shape centered on y ', and is formed so as to be continuous with the head 20a. Non-eccentric portion 20c of knock pin 20
Has a cylindrical shape centered on the rotation axis 20y, and is formed so as to be continuous with the eccentric portion 20b. The eccentric portion 20b is formed to have a smaller diameter than the head 20a so as to fit below the head 20a, and to have a slightly smaller diameter than the pin insertion hole 21 in the flange 7a of the pinion driving device 7. I have. The non-eccentric portion 20c is formed to have a smaller diameter than the eccentric portion 20b so as to fit below the eccentric portion 20b, and is formed to have a slightly smaller diameter than the pin fitting hole 22 in the turning frame 2. Therefore, the eccentric part 20 of the knock pin
b and the non-eccentric portion 20c are respectively inserted into the pin insertion hole 21 on the pinion drive device 7 side and the pin insertion hole 2 on the revolving frame 2 side.
2 and the head 20a of the knock pin 20 is
When the pinion is rotated about 0y, the pinion driving device 7 and the pinion 6 are displaced as if performing a rice hulling motion and change the distance between the inner gear 3a of the inner ring 3 and the center of the pinion 6. Reference numeral 23 denotes a plurality of bolts 2 for attaching the pinion driving device 7 to the revolving frame 2 and fixing the position.
4 is formed on a flange 7 a of the pinion drive device 7 and is used to attach the pinion drive device 7 to the revolving frame 2 when the bolt 2
A bolt insertion hole 25 for inserting the shaft portion 3 is a screw hole formed in the revolving frame 2 and screwing the screw portion of the bolt 23 when the pinion driving device 7 is mounted on the revolving frame 2. The diameter D ₁ of the bolt insertion hole 24 is
Than the diameter D ₂ of the shaft portion 3 to a larger diameter, so that impart a slight play between the inner and outer circumferential surfaces of the shaft portion of the bolt 23 of the bolt insertion holes 24. The eccentric amount b of the eccentric portion 20b of the knock pin 20 is equal to the diameter D of the bolt insertion hole 24.
Set to be less than half of the difference between the diameter D ₂ of the shaft portion ₁ and the bolt 23, centered within the play of the internal gear 3a and the pinion 6 between the shaft portion of the bolt insertion hole 24 and the bolt 23 The distance between them can be changed. When the pinion driving device 7 is mounted on the turning frame 2 in the turning device of the construction machine having such a structure, the bolt 23 is inserted into the bolt insertion hole 24 of the flange 7 a and the screw is inserted into the screw hole 25 of the turning frame 2. Combine. In this case, the bolt 23 is loosely tightened so that the bottom surface of the head 23a of the bolt 23 does not contact the upper surface of the flange 7a. Then, the pinion driving device 7 is temporarily fixed to the revolving frame 2 such that the pinion driving device 7 can be relatively displaced by play between the shaft portion of the bolt 23 and the bolt insertion hole 24.
Also, before and after this, the eccentric portion 20b of the knock pin 20
And the non-eccentric portion 20c are respectively inserted into a pin insertion hole 21 on the pinion drive device 7 side and a pin insertion hole 22 on the revolving frame 2 side.
To fit. Next, when the head 20a of the knock pin 20 is rotated, the non-eccentric portion 20c of the shaft of the knock pin 20 is rotated.
Is rotated about the rotation axis 20y, and the eccentric portion 20b is also rotated accordingly, so that the pinion driving device 7 is displaced with respect to the revolving frame 2 and, accordingly, the pinion 6 is also displaced. The distance between the internal gear 3a of the inner ring 3 and the center of the pinion 6 can be changed. Therefore, by performing such an operation, it is possible to adjust the distance between the center of the internal gear 3a and the pinion 6 so as to reduce the backlash between the internal gear 3a and the pinion 6. [0026] In the example shown here, so as to become less than half of the difference between the diameter D ₂ of the shank diameter D ₁ and the bolt 23 of the bolt insertion holes 24 the eccentricity b of the eccentric portion 20b, due to the knock pin 20 Since the free displacement of the pinion driving device 7 is not restricted by the bolt 23, when the turning operation of the head 20a of the knock pin 20 becomes impossible during the turning process, the pinion 6 is moved to the internal gear. It means that it is fitted as deep as possible between 3a. Therefore,
If the knock pin 20 is turned to a position where it cannot be turned and then turned to a position slightly returned from this position, the backlash between the internal gear 3a and the pinion 6 can be automatically minimized without visual confirmation. The backlash can be adjusted to an appropriate state without requiring special skills. After the backlash is adjusted in this way, the temporarily fixed bolt 23 is fixed to the head 23a by the flange 7a.
By firmly tightening the pinion driving device 7, the pinion drive device 7 is permanently fixed to the revolving frame 2 to fix the position. According to the turning device of the construction machine, the backlash generated between the internal gear 3a and the pinion 6 can be reduced as compared with the related art by attaching the pinion driving device 7 to the turning frame 2 through the above operation. As a result, the working accuracy of the construction machine can be improved, and the comfort of the construction machine can be improved. Further, since the backlash can be adjusted to be small by operating the head 20a of the knock pin 20, the tolerance range relating to the backlash of the single unit and the finishing condition of the turning frame 2 is set to be larger (lower finishing accuracy) than before. Even in this case, it is possible to repeatedly produce a turning device of the same construction machine that hardly causes backlash between the internal gear 3a and the pinion 6. Further, the knock pin 20 can be manufactured at a low cost although the manufacturing cost is slightly increased as compared with the conventional knock pin 10 because the eccentric portion 20b is added to the conventional knock pin 10. As shown in FIG.
The square head 20a may be scaled. Head 2
When such a scale is attached to 0a, the scale can be used as a guide when the knock pin 20 is rotated.
The turning operation of the knock pin 20 can be operated with an eye on the line of sight, and the backlash between the internal gear 3a and the pinion 6 can be adjusted efficiently. In the example shown here, the head 20a of the knock pin 20 has a hexagonal shape, but the structure of the head 20a is not limited as long as it can be rotated. In the example shown here, the eccentric portion 20b and the non-eccentric portion 20c of the knock pin are configured to fit into the flange 7a side and the turning frame 22 side of the pinion driving device 7, respectively.
Can be achieved by fitting the eccentric portion 20b into the flange 7a side of the pinion drive device 7 and the eccentric portion 20b into the revolving frame 22 side. As is apparent from the above description, since the turning device for a construction machine according to the present invention employs the means described in the section "Means for Solving the Problems", the knock pin By changing the distance between the center of the internal gear and the pinion by manipulating the head, the backlash generated between the internal gear and the pinion can be reduced as compared with the related art. As a result, the working accuracy of the construction machine can be improved, and the comfort of the construction machine can be improved. In addition, since the backlash can be adjusted to be smaller by operating the head of the knock pin, even if the tolerance range for the backlash of the single unit or the finishing condition of the revolving frame is set larger than before, the internal gear and the pinion can be adjusted. It is possible to repeatedly produce a turning device of the same construction machine that hardly causes a backlash therebetween. Furthermore, since the knock pin is sufficient if an eccentric part is added to the conventional knock pin,
Although the production cost is slightly higher than the conventional knock pin,
It can be manufactured at low cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view of a main part of a turning device of a construction machine according to an embodiment of the present invention. FIG. 2 is an enlarged view of a part A of FIG. FIG. 3 is an enlarged perspective view of a knock pin in the turning device of the construction machine shown in FIG. 1; FIG. 4 is a bottom view of the knock pin of FIG. 3; FIG. 5 is a plan view showing a modification of the knock pin of FIG. 3; FIG. 6 is a vertical sectional view of a main part of a turning device of a construction machine according to a conventional example. FIG. 7 is an enlarged view of a part shown in FIG. 6; FIG. 8 is an enlarged perspective view of a knock pin in the turning device of the construction machine shown in FIG. 6; FIG. 9 is a bottom view of the knock pin of FIG. 8; DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Revolving frame 3 Inner ring 3a Inner gear 4 Outer ring 5 Rolling element 6 Pinion 7 Pinion driving device 7a Flange 10 Knock pin 11 Pin insertion hole 12 (provided on flange 7a) 12 (provided on revolving frame 2) Pin insertion hole 13 Bolt 14 Bolt insertion hole 15 Screw hole 20 Dowel pin 20a Head 20b (of knock pin 20) Eccentric part 20c (of knock pin 20) Non-eccentric part 21 (of knock pin 20) Pin (provided on flange 7a) Insertion hole 22 Pin insertion hole 23 (provided in the turning frame 2) Bolt 24 Bolt insertion hole 25 Screw hole

Continuation of front page    (72) Inventor Nobuo Uzawa             Hitachi Construction Machinery Co., Ltd.             Tsuchiura factory (72) Inventor Yuji Igawa             Hitachi Construction Machinery Co., Ltd.             Tsuchiura factory (72) Inventor Takeshi Kurihara             Hitachi Construction Machinery Co., Ltd.             Tsuchiura factory (72) Inventor Takeshi Shibukawa             Hitachi Construction Machinery Co., Ltd.             Tsuchiura factory F-term (reference) 2D015 DA04                 3J030 AB01 BA01 BA10 CA10

Claims (1)

Claims: 1. An inner ring having an internal gear at an inner peripheral portion and fixed to a base, and an outer ring fixed to a revolving frame side to surround the inner ring and capable of turning around the inner ring. And a pinion that meshes with the internal gear of the inner ring, and a pinion drive device that rotationally drives the pinion, and performs a turning operation on a turning device of a construction machine in which the pinion drive device is mounted on the turning frame by bolts. And a knock pin having an eccentric portion that is eccentric with respect to the rotation axis and a non-eccentric portion that is not eccentric with respect to the rotation axis. The distance between the center of the inner gear of the inner ring and the center of the pinion is obtained by rotating the head of the knocking pin by inserting the pin into the pin insertion hole formed in each of the member on the pinion drive device side and the member on the turning frame side. Determined swing apparatus characterized by being configured so as to change the.