JP3284065B2 - Planetary gear reducer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crawler belt driving device for a hydraulic shovel, a hydraulic crane or the like, or a planetary gear reduction device suitably used for a rope winch or the like of a hydraulic crane.

[0002]

2. Description of the Related Art Generally, a crawler belt driving device for driving a crawler belt of a hydraulic shovel, a hydraulic crane, or the like is provided with a planetary gear reduction device for reducing the rotational output of a rotation source to obtain a large output.

A planetary gear speed reducer of this type according to the prior art is shown in FIGS. 5 to 10 as an example of a state in which it is mounted on a crawler belt driving device such as a hydraulic shovel.

In FIG. 5, reference numeral 1 denotes a support member fixed to a side frame or the like of a lower traveling body, and a hydraulic motor 2 as a rotation source is integrally attached to one end of the support member 1. On the other end of the support member 1, a cylindrical stopper portion 1A for positioning a carrier 33 described later in the axial direction is formed.

[0005] Reference numeral 3 denotes a covered cylindrical housing which is a rotating body. The housing 3 includes a drum 4 located on the outer peripheral side of the support member 1, a ring gear 5 provided with an internal gear 5 A on the inner peripheral side, and a ring gear 5. And a disk-shaped lid 6 covering the cover 5.

Here, the drum 4 is rotatably supported by the support member 1 via a tapered roller bearing 7, and a crawler belt driving sprocket 8 is mounted on its outer peripheral side by bolts 9. One end of the ring gear 5 is connected to a bolt 10.
The cover 6 is fixed to the other end of the ring gear 5 by bolts 11. further,
The inner surface of the lid 6 is fitted with a liner 12 which is located at the center and slides on a distal end surface of a sun gear 17 which will be described later.

Reference numeral 13 denotes an annular hub spline-connected to the outer periphery of the other end of the support member 1, and 14 denotes a nut screwed around the outer periphery of the stopper 1A of the support member 1, respectively. The tapered roller bearing 7 is positioned in the axial direction. The hub 13 is provided with a carrier 33.
Thus, the carrier 33 is fixed to the support member 1 via the hub 13 in a state where the carrier 33 is restricted in rotation.

Reference numeral 15 denotes a rotary shaft for deriving the rotational output of the hydraulic motor 2. One end of the rotary shaft 15 is
Is linked to A first-stage sun gear 17, which will be described later, is integrally formed on the other end of the rotating shaft 15 extending toward the lid 6, and its tip end surface is in sliding contact with the liner 12.

Reference numeral 16 denotes a first-stage reduction gear mechanism. As shown in FIG. 6, the reduction gear mechanism 16 includes a sun gear 17 integrally formed on the other end of the rotating shaft 15 and a sun gear 17.
And a plurality of (only one is shown) planetary gears 18 which are arranged so as to mesh with the internal gear 5 </ b> A of the ring gear 5 and revolve while rotating around the sun gear 17, via pins 19 and bearings 20. A carrier 21 rotatably supports the planetary gear 18 and transmits the revolution of the planetary gear 18 to a second-stage sun gear 23 described later.

Reference numeral 22 denotes a second-stage reduction gear mechanism. The reduction gear mechanism 22 is spline-coupled to the first-stage carrier 21, and includes a sun gear 23 to which only the revolution of the planetary gear 18 is transmitted, and a sun gear 23. Gear 23 and internal gear 5A of ring gear 5
And a planetary gear 24 that revolves around the sun gear 23 while revolving around the sun gear 23, and rotatably supports the planetary gear 24 via a pin 25 and a bearing 26. Carrier 2 transmitting to the sun gear 29 of the stage
7 is comprised.

Reference numeral 28 denotes a third reduction gear mechanism, which is the final reduction gear. The reduction gear mechanism 28 is spline-coupled to the second carrier 27, and only the revolution of the planetary gear 24 is transmitted. A sun gear 29; a planetary gear 30 meshing with the sun gear 29 and the internal gear 5A of the ring gear 5 to rotate around the sun gear 29; a pin 31 and a bearing 32
3 that rotatably supports the planetary gear 30 through the
And 3. The inner circumference of one end of the carrier 33 meshes with the hub 13, and the hub 13 meshes with the support member 1, so that the carrier 33 is fixed to the support member 1 in a state where the rotation is restricted.

Numeral 34 denotes a sun gear 1 which is accommodated in a spacer accommodating portion 21G, which will be described later, provided in the first stage carrier 21.
7 shows an annular spacer disposed between the first and second sun gears 17 and 23, the spacer 34 receiving the axial load of the sun gears 17 and 23 and moving the sun gears 17 and 23 in the axial direction of the rotating shaft 15. It is for positioning.

Reference numeral 35 denotes an annular spacer which is accommodated in the spacer accommodating portion of the carrier 27 of the second stage and is disposed between the sun gears 23 and 29.
The sun gears 23 and 29 are positioned in the axial direction of the rotating shaft 15 while receiving the axial loads of the sun gears 3 and 29.

In the planetary gear reduction device configured as described above, when the rotary shaft 15 is rotated by the hydraulic motor 2, the rotation is reduced by the first reduction gear mechanism 16 at a predetermined reduction ratio, and the planetary gear 18 Is output from the carrier 21 to the second stage sun gear 23. The second stage reduction gear mechanism 22 further reduces the rotation from the carrier 21 at a predetermined reduction ratio, and outputs only the revolution of the planetary gear 24 from the carrier 27 to the final stage sun gear 29. Further, in the final stage reduction gear mechanism 28, the rotation of the carrier 33 with respect to the support member 1 is restricted, so that the rotation output from the carrier 27 is reduced by the reduction gear mechanism 2.
In a state where the speed is reduced at a predetermined speed reduction ratio by 8, the power is transmitted from the sun gear 29 to the ring gear 5 via the planetary gear 30, and a large rotational torque is generated in the housing 3 including the ring gear 5 and the drum 4.

Thus, the rotational output of the hydraulic motor 2 is sequentially reduced by the reduction gear mechanisms 16, 22, and 28, transmitted to the housing 3 as a large torque, and crawler belt (not shown) wound around the sprocket 8. Is driven at low speed to drive a hydraulic shovel or the like.

[0016]

By the way, in the planetary gear reduction device according to the prior art as described above, the spacer 34 accommodated in the spacer accommodating portion 21G of the carrier 21 drops off from the spacer accommodating portion 21G in the radial direction during the operation. Or the spacer 35 accommodated in the spacer accommodating portion of the carrier 27 may fall off from the spacer accommodating portion in the radial direction.

Here, FIG.
1 shows a state in which it has fallen radially from the first spacer accommodating portion 21G.

As described above, the spacer 34 is used for the carrier 21.
If the spacer 35 falls off from the carrier 27, the axial positioning with respect to the sun gears 23 and 29 is not properly performed. And the stable operation of the planetary gear reduction device is impaired.

Also, for example, the dropped spacers 34 and the like come into contact with the planetary gears 18 and the like and are broken, and the fragments are caught between the gears constituting the reduction gear mechanisms 16, 22, and 28 to damage them. In addition, there is a problem that the life of the planetary gear reduction device is significantly reduced.

Here, the reason why the spacer 34 falls off the carrier 21 will be described below with reference to FIGS.

[0021] First, there will be described a configuration of the carrier 21, the carrier 21 is arranged Nde clamping the planetary gears 18
A pair of annular disks 21A and 21B having different inner diameters from each other
To connect the annular disks 21A, 21B in the axial direction.
Ribs 21C and one annular disk 2 having a small inner diameter.
A cylindrical mounting portion 21D that protrudes axially outward from the outer surface of 1A and has a spline formed on the inner peripheral side to mesh with the sun gear 23, and a fixed interval (circumferential direction) between the annular disks 21A and 21B ( For example, 120 °), a plurality of pin holes 21E into which the pins 19 are press-fitted, and the annular disks 21A, 21 located around the respective pin holes 21E.
B, protruding in the form of a truncated cone on the inner surface of the
Are formed integrally by casting.

On the inner side surface of the annular disk 21A, an annular spacer accommodating portion 21G is provided at the center of the shaft so as to be recessed, and the spacer 34 is accommodated in the spacer accommodating portion 21G. The configuration is such that the spacer 34 can be prevented from falling off in the radial direction.

Here, as shown in FIG.
21G and the annular disk 21 to hold the
It is necessary to ensure a step of dimension A (for example, A = 3 mm) between the inner surface of A and A. In this case, the annular disk 21A
Is set at a position of dimension B from the outer surface of the annular disk 21B, but a seating surface 21F which is a sliding surface of the planetary gear 18 is provided.
Usually, the dimension B is a dimension including a relatively large plus tolerance (for example, B = 50 ± 3 m
m).

Therefore, as shown in FIG. 10, for example, when the dimension B becomes the maximum dimension B 'within the tolerance range and the inner surface of the annular disk 21A fluctuates, the inner surface and the spacer accommodating portion are changed. 21G is a minimum dimension A ′ reduced by a tolerance of the dimension B, and the spacer accommodating portion 21G
The spacer 34 cannot be securely held in the inside. And
When the inner surface of the annular disk 21A fluctuates, the seat surface 2
If the protrusion dimension C of 1F becomes the maximum dimension C ′ obtained by adding the tolerance of the dimension B, and becomes larger than the thickness dimension D of the spacer 34 (C ′> D), the spacer 34 becomes the spacer accommodating portion. 21G may fall off in the radial direction, causing problems such as biting into the planetary gear 18.

The carrier 27 constituting the second-stage reduction gear mechanism 22 is also configured in the same manner as the first-stage carrier 21. Therefore, the spacer 35 is separated from the carrier 27 by the same diameter as that described above. There is a problem that it falls off in the direction.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has a planetary gear reduction device capable of reliably preventing a spacer provided between a sun gear and a carrier from falling off the carrier. It is intended to provide.

[0027]

In order to solve the above-mentioned problems, the present invention provides a sun gear, and a plurality of planetary gears that mesh with the sun gear and revolve around the sun gear while rotating around the sun gear. The present invention is applied to a planetary gear reduction device comprising a carrier rotatably supporting each of the planetary gears, and having an annular spacer provided between the carrier and the sun gear.

[0028] The feature of the configuration invention of claim 1 is employed, the carrier, the respective planetary gears Nde nip disposed
A disc of a pair of annular is, a plurality of ribs connecting the respective disc in the axial direction, the cylindrical mounting portion protruding from the shaft Direction from the outer surface of one of the disc out of the disc A spacer accommodating portion annularly recessed on the inner surface of the one disk to accommodate the spacer, and a spacer accommodating portion for preventing the spacer from dropping from the spacer accommodating portion. It is located radially outward before the inner surface of the one disc
And a plurality of projections extending radially inward from the respective ribs and engaging with the outer periphery of the spacer .

According to the above configuration, each of the protrusions provided on the inner side surface of one of the disks and located radially outward from the spacer accommodating portion and extending radially inward from the respective ribs , By engaging with the outer peripheral side of the spacer accommodated in the spacer accommodating portion, it is possible to prevent the spacer from dropping radially from the spacer accommodating portion.

[0030]

Further , each of the projections is positioned radially at the position of the rib .
Since it is provided so as to extend toward the side, it is possible to prevent the projections from interfering with the planetary gear rotatably supported by the carrier.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In the present embodiment, the same components as those of the above-described related art are denoted by the same reference numerals, and description thereof will be omitted.

In the drawing, reference numeral 41 denotes a first-stage reduction gear mechanism. The reduction gear mechanism 41 includes a sun gear 17 and a sun gear 1 in substantially the same manner as the conventional reduction gear mechanism 16.
A planetary gear 18 that revolves while rotating around the
9 and a carrier 42 rotatably supporting the planetary gear 18 via the bearing 20, but the configuration of the carrier 42 is different from that of the carrier 21 according to the related art.

Reference numeral 43 denotes a second-stage reduction gear mechanism. The reduction gear mechanism 43 is substantially the same as the prior art reduction gear mechanism 22 and has a sun gear 23 to which only the revolution of the first-stage planetary gear 18 is transmitted. And a planetary gear 24 revolving around the sun gear 23 while revolving around the sun gear 23, and a carrier 44 described later rotatably supporting the planetary gear 24 via a pin 25 and a bearing 26. Is different from the carrier 27 according to the prior art.

Since the first-stage carrier 42 and the second-stage carrier 44 have substantially the same configuration, the first-stage carrier 42 will be described below with reference to FIGS. The description of the second-stage carrier 44 is omitted.

In the drawing, reference numeral 42 denotes a carrier constituting the first-stage reduction gear mechanism 41. The carrier 42 is substantially the same as the carrier 21 according to the prior art, and
A pair of annular discs 42A, 42B which clamping Nde disposed inside diameter mutually different, and three ribs 42C which connects respective annular discs 42A, and 42B in the axial direction, inner diameter smaller
A cylindrical mounting portion 42D protruding axially outward from the outer surface of one of the annular disks 42A and a plurality of annular holes 42A and 42B formed at a constant interval (for example, 120 °) in the circumferential direction. And a plurality of seating surfaces 42F protruding from the inner surfaces of the annular disks 42A and 42B located around the respective pin holes 42E, and an annular disk 42A for accommodating the spacer 34. An annular spacer accommodating portion 42G is provided on the inner surface. However, the carrier 42
Is different from the carrier 21 according to the prior art in that each of the projections 42H described below is provided.

42H, 42H,...
The three protrusions projecting from the inner surface of the annular disk 42A are positioned radially outward from G, and each of the protrusions 42H extends radially inward from the inner surface of each rib 42C. It is provided to be. Then, each projection 42H is
By engaging the outer peripheral side of the spacer 34, the spacer 34
To prevent radial dropout from the spacer accommodating portion 42G in the radial direction
are doing.

Here, as shown in FIG.
The protrusion dimension E of the protrusion 42H from the inner side of the A
The projecting dimension of 2F is the maximum dimension C ', and the spacer 34
Assuming that the thickness dimension of D is D, it is set as in the following equation 1.

[0039]

## EQU1 ## C'-E <D

That is, the dimension from the outer surface of the annular disk 42B to the inner surface of the annular disk 42A is the maximum dimension B 'within the tolerance range, and the projected dimension of the seat surface 42F is smaller than the thickness D of the spacer 34. Even if the maximum dimension C ′ becomes larger,
The gap generated between each projection 42H and the planetary gear 18 is
The configuration is such that the thickness D of the spacer 34 can be made smaller.

As shown in FIG. 4, each rib 42C is
Between the planetary gears 18 rotatably supported by the carrier 42
And the circumferential width F of the protrusion 42H provided at the position of each rib 42C is set to a size that does not interfere with the tooth tip of the planetary gear 18 rotatably supported by the carrier 42. .

On the other hand, the carrier 44 constituting the second-stage reduction gear mechanism 43 is also provided with the planetary gears 24 interposed therebetween, and has a different inside diameter from each other , similarly to the carrier 42 described above.
And a pair of annular disks 44A and 44B
A, and three ribs 44C which connects in the axial direction 44B, inner
One of the annular disks 44A having a small diameter is protruded axially outward from the outer surface of the annular disk 44A , and meshes with the sun gear 23 on the inner peripheral side.
Constant intervals (for example, 1) in the circumferential direction between the cylindrical mounting portion 44D on which the splines are formed and the annular disks 44A and 44B.
20 °) and the pins 25 are press-fitted.
And a plurality of pin holes 44E that, positions around the respective pin hole 44E
A plurality of seating surfaces 44F, which protrude in the shape of a truncated cone from the inner surfaces of the annular disks 44A and 44B and form sliding surfaces of the planetary gears 24, and the spacer 35 are accommodated therein. For annular disk
An annular spacer accommodating portion 44 recessed on the inner surface of 44A
And G, that consists the protruding portion 44H of the spacer housing portion positioned radially outside the side of the 44G 3 pieces projecting from the inner surface of the annular discs 44A and (only one shown).

The projections 44H are engaged with the outer periphery of the spacer 35, so that the spacer 35 can be prevented from dropping from the spacer accommodating portion 44G in the radial direction.

As for the third stage reduction gear mechanism,
Since it has the same configuration as the reduction gear mechanism 28 according to the related art, the description thereof is omitted.

The planetary gear reduction device according to the present embodiment has the above-described configuration, and its basic operation is not particularly different from that of the prior art.

However, in the present embodiment, the carrier 42
By providing three projections 42H on the outer peripheral side of the spacer accommodating portion 42G, the spacer accommodating portion 4
The outer peripheral side of the spacer 34 accommodated in the 2G is a protrusion 42
H. As a result, even if, for example, the protrusion dimension of the bearing surface 42F serving as the sliding surface of the planetary gear 18 becomes the maximum dimension C 'that is larger than the thickness dimension D of the spacer 34, the spacer 34 will fall off in the radial direction. Can be reliably prevented by the protrusion 42H.

Also, the carrier 44 has the protrusions 4
By engaging 4H with the outer peripheral side of the spacer 35, the spacer 35 accommodated in the spacer accommodating portion 44G can be reliably prevented from dropping from the spacer accommodating portion 44G in the radial direction.

Accordingly, the sun gears 17 and 23 can be properly positioned in the axial direction by the spacer 34, and the sun gears 23 and 29 can be properly positioned in the axial direction by the spacer 35. The operation of the reduction gear transmission can be stabilized for a long time.

Further, the spacers 34 and 35 are
The spacers 34, 35 and the planetary gears 18, 24, etc. can be prevented from being damaged by dropping from the gears 2, 44 and being engaged with the planetary gears 18, 24, etc. The life can be reliably prevented from being shortened.

[0050]

[0051] In the above embodiment, the case of applying to the planetary gear reduction system having a reduction gear mechanism of the third stage has been described, the present invention is not limited thereto, 1
The present invention may be applied to a planetary reduction gear having a reduction gear mechanism with two, four, or more stages.

Further, the carriers 33 constituting the third-stage reduction gear mechanism 28 are also provided with the carriers 42, 44.
It is also possible to provide a spacer accommodating portion and a protruding portion similar to those described above, and hold the spacer with the spacer accommodating portion and the protruding portion.

[0053]

As has been described above in detail, according to the first aspect of the present invention, whereas located radially outside side from the spacer housing portion
Extend radially inward from each rib on the inner surface of the disk
Setting only a plurality of projections that, prevents respective projections from was configured to engage the outer peripheral side of the spacer contained in the spacer housing portion, reliably spacer from falling off the spacer housing portion in the radial direction The spacer can be secured in the housing. Thereby, the axial load of each sun gear can be received by the spacer, and each sun gear can be appropriately positioned in the axial direction, and the operation of the planetary gear reduction device can be stabilized for a long period of time. Further, it is possible to prevent the spacers and the planetary gears from being damaged by the spacers dropped from the carrier being caught by the planetary gears and the like, and to prolong the life of the planetary gear reduction device.

Further , since each projection is provided to extend radially inward at the position of the rib constituting the carrier, each projection interferes with the planetary gear rotatably supported by the carrier. Can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is an enlarged vertical sectional view showing a reduction gear mechanism of a planetary gear reduction device according to an embodiment of the present invention.

FIG. 2 is a partially broken perspective view showing a carrier in FIG.

FIG. 3 is an enlarged longitudinal sectional view showing a carrier in FIG. 1;

FIG. 4 is a side view of the carrier as viewed from the direction of arrows IV-IV in FIG. 3;

FIG. 5 is a longitudinal sectional view of a conventional planetary gear reduction device.

FIG. 6 is an enlarged vertical sectional view showing a reduction gear mechanism in FIG. 5;

FIG. 7 is an enlarged vertical sectional view showing a state in which a spacer in FIG. 6 has dropped from a carrier.

FIG. 8 is a partially broken perspective view showing a carrier according to the prior art.

FIG. 9 is an enlarged longitudinal sectional view showing a carrier in FIG. 6;

FIG. 10 is a longitudinal sectional view showing the carrier in a state where the spacer can be dropped off.

[Explanation of symbols]

 28, 41, 43 Reduction gear mechanism 17, 23, 29 Sun gear 18, 24, 30 Planetary gear 33, 42, 44 Carrier 34, 35 Spacer 42A, 42B, 44A, 44B Annular disk (disk) 42C, 44C Rib 42D, 44D Cylindrical mounting part 42G, 44G Spacer accommodation part 42H, 44H Projection part

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeshi Kurihara 650, Kunitachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. Tsuchiura Plant (72) Inventor Shingo Kishimoto 1-2 shares in Sasagaoka, Mizuguchi-machi, Koka-gun, Shiga Prefecture (56) References JP-A-3-48044 (JP, A) JP-A-1-122542 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 1/28

Claims (1)

(57) [Claims] A sun gear; a plurality of planetary gears that mesh with the sun gear and revolve around the sun gear while rotating around the sun gear;
Consists of a carrier which rotatably supports the respective planetary gears, the planetary gear reduction device comprising an annular spacer between the said sun gear and said carrier, said carrier is, Nde clamping the respective planetary gears One that was arranged
A pair of annular discs, a plurality of ribs for connecting the discs in the axial direction, and an axial direction from an outer surface of one of the discs.
A cylindrical mounting portion protruding in the opposite direction, a spacer receiving portion annularly concavely formed on an inner surface of the one disk for receiving the spacer, and a case where the spacer falls off from the spacer receiving portion. To prevent this, each of the ribs is located on the inner surface of the one
The provided extending toward the radially inward from each of
A planetary gear reduction device comprising: a plurality of projections that engage with an outer peripheral side of a spacer .