JP2003112672A - Final reduction gear in crawler vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a final reduction gear for achieving compactness and low cost without projecting to the outside of a crawler belt, even if mounting a narrow crawler belt. SOLUTION: A cross roller bearing 12 for rotatably supporting a sprocket hub 13 is disposed in one row. An outer race and/or inner race of the cross roller bearing 12 are integrally constituted with components 11d, 11e and 13 of the final reduction gear 10. The final reduction gear 10 is desirably an inner planetary type final reduction gear. A length T from a width center of the cross roller bearing 12 up to an outside end face of the final reduction gear 10 is made substantially same as a length L from a width center of a link 91 of the crawler belt 90 up to an outside end face of the link 91 or below the length L.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a final reduction gear device for a tracked vehicle.

[0002]

2. Description of the Related Art Generally, in a tracked vehicle, a steering gear box is arranged in the left and right center of the rear part of the vehicle, and final reduction gears are arranged on the left and right sides of the steering gear box. The sprocket drives the crawler tracks of the left and right traveling devices to enable traveling and turning.

Further, in the final reduction gear, usually two or more reduction gears are required in order to obtain a large reduction ratio, so that the final reduction gear has a large volume and projects outward of the vehicle. is there. Therefore, usually, the output gear of the final reduction gear is made cylindrical by making the gear train of the final output stage a planetary gear train so that the crawler belt wound around the sprocket of this output does not interfere with the output gear. There is.

Further, since a radial load, a thrust load and a moment load are applied to the sprocket as the tracked vehicle runs on an uneven terrain, the sprocket or a hub to which the sprocket is attached (integrated sprocket and assembled sprocket is referred to. However, hereinafter, a bearing supporting a sprocket hub other than the tooth portion is generally constituted by arranging two tapered roller bearings or two angular contact ball bearings with their backs aligned with a predetermined span.

Taking a bulldozer as an example, referring to FIGS.
An example of a final speed reducer according to the related art will be described. First of all,
With reference to FIG. 10, a first example of the final speed reducer according to the conventional technique will be described. 9 is a side view of a bulldozer to which the final reduction gear transmission is applied, and FIG. 10 is a rear cross-sectional view of the final reduction gear transmission according to the first conventional technique, and is a cross-sectional view taken along line AA of FIG. 9.

In FIG. 9, the bulldozer 1 has a main frame 2 in the front-rear direction of the center of the vehicle, and the main frame 2 has a pair of left and right beams (here, only the left beam 2a is shown). Steering gear box 8 to which rotational power from the engine is transmitted between the left and right beams
Is provided. The left final reduction gear 70 is attached to the left outer surface of the beam 2a at the position of the steering gear box 8, and the crawler belt 90 of the left traveling device 4 is wound around the sprocket of the final reduction gear 70. Note that the same applies to the right side of the vehicle, and a description thereof will be omitted.

In FIG. 10, the final reduction gear device 70 is fixed to the beam 2a by a bolt 9 in the inner case 11a. The outer case 7 is provided outside the inner case 11a.
1b is fixed by a bolt, and both cases 11a and 71b constitute a final deceleration case. Furthermore, the outer case 7
1b The tapered roller bearing 72 has two
Individual pieces are arranged back to back with a predetermined span, and a sprocket hub 73 is rotatably supported by the tapered roller bearing 72. The sprocket 14 is attached to the outer peripheral portion of the sprocket hub 73 with bolts and nuts. ing. The sprocket 14 has a link 91 and a track plate 92.
A crawler belt 90 composed of is wound.

Inside the final reduction gear unit 70, a small gear 22 and a large gear 23 are arranged as a first reduction stage, and the small gear 2
A drive shaft 21 that transmits power from the steering gear box 8 is splined to the inner diameter portion 2. The large gear 23 is attached to the hub 24 with a bolt, and the inner diameter of the hub 24 is spline-fitted to the low tooth length portion of the sun gear 31. In addition, as the second speed reduction stage, the sun gear 31,
A planetary gear train including the planet pinion 32a, the carrier 32, and the ring gear 33 is arranged. The outer periphery of the ring gear 33 is splined to the inner diameter of the outer case 71b to prevent rotation. The carrier 32 has a cylindrical shaft portion 32b, and the drive disk 34 is spline-fitted between the outer peripheral portion near the outer end of the shaft portion 32b and the inner diameter portion of the sprocket hub 73. The carrier 32 is configured to drive the sprocket hub 73 and the sprocket 14 via the drive disk 34.

In the above configuration shown in FIGS. 9 to 10,
The load applied from the crawler belt 90 to the sprocket 14 is the bearing 7
2, outer case 71b, inner case 11a and bolt 9
Since it has a structure in which the beam 2a is firmly supported through the sprocket 14 and the power is transmitted to the sprocket 14 using the inner space of the cylindrical portion 71c of the outer case 71b, the structure has excellent durability.

On the other hand, as described above, with respect to the final reduction gear device 70 in which the planetary gear train is arranged inside the sprocket 14 (on the right side in the drawing) (hereinafter referred to as an inner planetary type), the outside of the sprocket (in the drawing). A planetary gear train is arranged on the left side (hereinafter,
An outer planetary type final reduction gear is considered. Therefore, an example of an outer planetary type final reduction gear device according to the second conventional technique will be described with reference to FIG. FIG. 11 is a rear cross-sectional view of the outer planetary type final reduction gear, which is a cross-sectional view taken along the line AA of FIG. 9.
In addition, the same components as those in FIG. 10 are denoted by the same reference numerals, and description thereof will be omitted below. The applicable machine is the same as the bulldozer shown in FIG.

In FIG. 11, the final speed reducer 80 is
A first gear having a small gear 22 and a large gear 23 meshing therewith
It has a speed reduction stage and a second speed reduction stage having a planetary gear train. The small gear 22 and the large gear 23 are arranged inside the sprocket 14 (on the right side in the drawing), and the sun gear 31, the planet pinion 82a and the carrier 82 of the planetary gear train are arranged.
The ring gear 83 is disposed outside the sprocket 14 (on the left side in the drawing). The long shaft portion 31b of the sun gear 31 is splined to the inner diameter portion of the hub 24 to which the large gear 23 is attached, so that power is transmitted from the large gear 23 to the sun gear 31. Has become.

Further, the ring gear 83 is attached via a hub 84 to the cylindrical portion 81c of the outer case 81b while being locked to rotate about its axis. The carrier 82 wraps the planetary gear train and attaches the bolt 8 to the sprocket hub 85.
2b, and is configured to drive the sprocket hub 85 and the sprocket 14.

In the structure shown in FIG. 11, power having a relatively small torque which is only reduced by the small gear 22 and the large gear 23 inside the sprocket 14 is supplied to the outer case 81.
Since the shaft portion 31b of the sun gear 31 may be thin because it is transmitted to the sun gear 31 through the inner space of the cylindrical portion 81c of b, the thick shaft portion 3 in the first conventional example is used.
2b and the large drive disk 34 are unnecessary. As a result, weight reduction and cost reduction are possible.

[0014]

However, as shown in FIG.
Further, the following problems remain in the final reduction gears 70, 80 according to the first and second conventional techniques shown in FIG. 11 and FIG. 11, respectively. (Problem of Final Reduction Gear 70 According to First Prior Art) (1) Two tapered roller bearings 72, 72 are arranged with a predetermined span in order to firmly support the sprocket 14, and the tapered roller bearings are further provided. Drive disk 34 on the outside of 72
10 is provided, the length T from the center of the two bearings 72, 72 to the outer end portion of the final reduction gear device 70 becomes long as shown in FIG. Therefore, the outer end portion of the final reduction gear device 70 becomes closer to the outer end surface of the crawler belt 90, and is easily damaged by rocks or the like. Further, in the case where a crawler track for which the crawler belt width W is reduced in order to prevent bending of the crawler plate 92 is mounted,
There is a fear that the outer end portion of the final reduction gear transmission 70 is outside the outer end portion of the crawler belt 90. (2) Further, as a result of the axial length C becoming large, the final reduction gear transmission 70 increases in weight and costs. (3) In order to transmit the large torque finally decelerated by the planetary gear train inside the sprocket 14 (right side in the drawing) to the sprocket 14 outside the tapered roller bearing 72 (left side in the drawing), it is long and thick. Since the shaft portion 32b, the large drive disk 34, and the spline processing related thereto are required, the material cost and the machining cost are increased and the cost is increased.

(Problem of Final Reduction Gear 80 According to Second Prior Art) (1) Two tapered roller bearings 72, 72 are arranged with a predetermined span to firmly support the sprocket 14, and this Since the planetary gear train is arranged outside the tapered roller bearing 72, the length T from the center of the two bearings 72, 72 to the outer end portion of the final reduction gear transmission 80 is smaller than that of the first conventional example. And become longer. Therefore, by offsetting the bearing 72 with respect to the sprocket 14 in the right direction (inside the final reduction gear) by the distance F, the outer end portion of the final reduction gear 80 is positioned inside the outer end of the crawler belt 90. I am trying to let you. As a result, a moment load due to the offset F is additionally applied to the bearings 72, 72, so that a bearing having a large capacity is required, and the device becomes large. (2) Since the outer end of the final reduction gear unit 80 is close to the outer end of the crawler belt 90, it is easily damaged by rocks or the like. In addition, when a rocky crawler track having a reduced track width W is mounted, the outer end portion of the final reduction gear device 80 may be located outside the outer end of the crawler belt 90. (3) As a result of the axial length C becoming large, the final reduction gear transmission 80
Is heavy and costly.

The present invention has been made in view of the above-mentioned problems, and provides a final speed reducer capable of realizing a compact size that does not protrude to the outside of the crawler belt even if a narrow crawler belt is mounted and a low cost. It is intended to be provided.

[0017]

In order to achieve the above object, the first aspect of the present invention is to provide a cross roller bearing in a single row as a bearing for rotatably supporting a sprocket hub in a final reduction gear transmission. In addition, the outer race and / or the inner race of the cross roller bearing are integrally formed with the components of the final reduction gear transmission.

According to the first invention, the following actions and effects are obtained. (1) Since the cross roller bearing can support radial load, thrust load and moment load in a single row, the axial space of the bearing supporting the sprocket can be limited to the width of the cross roller bearing. Thereby, the axial length of the final reduction gear transmission can be made compact. (2) By constructing the outer race and / or the inner race of the cross roller bearing integrally with other components of the final reduction gear transmission, the installation space of the bearing can be significantly reduced. Therefore, the cross roller bearing having a size corresponding to the required load bearing performance can be provided compactly.

In a second aspect of the invention, the final reduction gear according to the first aspect is an inner planetary type final reduction gear.

According to the second invention, the following actions and effects are obtained in addition to the actions and effects of the first invention. By disposing the planetary gear train inside the sprocket and occupying only the width of the cross roller bearing for the bearing, the axial length of the final reduction gear can be made more compact. Further, as a result, the thick shaft portion for outputting the carrier can be shortened, so that the weight and the cost can be reduced.

A third invention is the final reduction gear according to the second invention, wherein the length from the width center of the cross roller bearing to the outer end surface of the final reduction gear is the length from the width center of the link of the crawler track to the outer end surface of the link. It is configured to be substantially equal to or less than.

According to the third invention, the following actions and effects are obtained in addition to the actions and effects of the second invention. Even if the sprocket is arranged on the width center line of the cross roller bearing with an offset of zero, the outer end surface of the final reduction gear device does not protrude outward from the outer end surface of the link of the crawler belt. As a result, it is possible to freely select a crawler belt having a small width, and even in that case, the outer end portion of the final reduction gear device does not project outward from the outer end of the crawler belt and is not damaged by rocks or the like. Also, the vehicle width can be defined by the outer ends of the left and right crawler belts. Further, since the cross roller bearing can be used with zero offset, the load on the cross roller bearing can be minimized.

According to a fourth aspect of the invention, in the final reduction gear according to the second aspect, the outer race of the cross roller bearing is fixed, and the outer race is integrally formed with the case of the final reduction gear.

According to the fourth invention, in addition to the function and effect of the second invention, the cross roller bearing can be arranged close to the case of the final reduction gear, and the final reduction gear can be made extremely compact. As a result, the position of the outer end portion of the final reduction gear device can be made substantially the same as the outer end surface of the sprocket, so that the outer end portion of the final reduction gear device does not project outward from the outer end of the crawler belt.

According to a fifth aspect of the present invention, in the final reduction gear transmission according to the fourth aspect, the inner race of the cross roller bearing is divided into two parts, the inner race and the outer race, and each inner race is integrated with the carrier of the planetary gear and the sprocket hub. Is configured.

According to the fifth invention, the following actions and effects are obtained in addition to the actions and effects of the fourth invention. The assembly of the cross roller bearing is completed by assembling the sprocket hub to the carrier with bolts, and the carrier and the sprocket hub are integrally supported by the case of the final reduction gear via the cross roller bearing. Accordingly, the support of the sprocket hub and the transmission of power to the sprocket hub can be simultaneously performed via the carrier. As a result, it is possible to construct an extremely compact final reduction gear with a simple structure and a small number of parts.

As a result of the above, it is possible to provide a final reduction gear device which realizes a compactness that does not protrude to the outside of the crawler belt even when a crawler belt having a narrow width is mounted, and a low cost.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a bulldozer will be described in detail below with reference to the drawings. The bulldozer to which the present invention is applied has the same configuration as that shown in FIG.

First, a first embodiment will be described with reference to FIG. FIG. 1 is a rear cross-sectional view of the final reduction gear unit of the present embodiment, and shows a cross-sectional view taken along the line AA of FIG. 9. In the following,
The same components are assigned the same reference numerals and explanations thereof are omitted.

In FIG. 1, the final reduction gear transmission 10 includes cross roller bearings 12 arranged in a single row with an offset of zero with respect to the width center of the sprocket 14. The inner race of the cross roller bearing 12 has two ring-shaped members 11
The two ring-shaped members 11d and 11e are attached to and supported by the tip (outer end) of the cylindrical portion 11c of the outer case 11b with bolts 11f. This allows the rollers of the cross roller bearing 12 to be directly incorporated. Further, the joint surface between the cylindrical portion 11c and the ring-shaped member 11d, and the ring-shaped member 11d
A seal assembly 15 that seals between the outer race side member of the cross roller bearing 12 and the sprocket hub 13 in the present embodiment is provided on the outer peripheral portion of the cylindrical portion 11c. The inner diameter of the seal assembly 15 may be made larger than that shown in the figure, and the ring-shaped member 11d and the cylindrical portion 11c may be integrally formed. Furthermore, the sprocket hub 13
A roller rolling surface 13a is formed on the inner circumference of the sprocket hub 13 so that the sprocket hub 13 constitutes the outer race of the cross roller bearing 12.

The effect of the above configuration will be described. The present cross roller bearing 12 is different from a bearing assembly preassembled using a dedicated inner race and outer race as in the related art, in which the inner race and / or the outer race are integrally formed with other members, and the roller of the bearing is directly formed. Since the structure can be incorporated, the cross roller bearing 12 having a size corresponding to the required load bearing performance can be compactly arranged.

Further, by disposing the cross roller bearings 12 in a single row, the final reduction gear transmission 10 is arranged from the width center of the bearings.
The length T to the outer end of the crawler belt 90 is substantially equal to or less than the length L from the width center of the link 91 of the crawler belt 90 to the outer end surface of the link 91. As a result, even if the cross roller bearing 12 and the sprocket 14 are arranged with an offset of zero relative to each other and the width W of the crawler belt 90 is small, or even if the predetermined gap V and the width W of the crawler belt 90 are set freely, both are It is possible to prevent the outer end portion of the final reduction gear transmission 10 from projecting outward beyond the outer end of the crawler belt 90.

Next, another embodiment of the first embodiment will be described with reference to FIGS. 2 is a rear cross-sectional view of the first alternative embodiment, and FIG. 3 is a rear cross-sectional view of the second alternative embodiment of the first embodiment, each showing an AA cross-sectional view of FIG. 9.

In FIG. 2, the final reduction gear transmission 10A is provided with a sprocket 14 at a position of a predetermined distance S from the beam 2a, and a predetermined gap V from the beam 2a with a standard width W.
1 crawler belt 90A is worn. Further, a sprocket hub 13A is attached such that the sprocket 14 is located at a position offset inward (to the right in the drawing) by a distance F from the cross roller bearing 12. Further, in FIG. 3, the final reduction gear transmission 10B is mounted with a sprocket hub 13B such that the sprocket 14 is located at a position offset from the cross roller bearing 12 outward (to the left in the drawing) by a distance F, and from the beam 2a. A crawler belt 90B having a width W2 wider than the standard specification width W1 is mounted with a predetermined gap V therebetween.

2 and 3, the sprocket hub 13A is constructed by using the final reduction gear 10A or 10B which has the same structure except for the sprocket hubs 13A and 13B.
The standard bulldozer can be configured by mounting the sprocket hub 13B and the sprocket hub 13B can be configured by the sprocket hub 13B. Further, in that case, by utilizing the fact that the distance T from the cross roller bearing 12 to the outer end portion of the final reduction gear transmission 10A is short, the outer end portion of the final reduction gear transmission does not project outside the outer end of the crawler belt 90A. The offset distance F is set to. In addition, sprocket hubs 13A and 13B
The respective offset distances F are equalized to equalize the loads on the cross roller bearings 12.

Next, a second embodiment will be described with reference to FIG. FIG. 4 is a rear cross-sectional view of the final reduction gear system of the present embodiment, which is a cross-sectional view taken along the line AA of FIG. 9. In FIG. 4, first, the final reduction gear 40A is provided in such a manner that the cross roller bearing 12 is offset inward (rightward in the drawing) from the width center of the sprocket 14 and brought close to the outer case 11b. next,
The drive disk 44 also serving as a cover is fastened to the outer end surface of the sprocket hub 13 with bolts 45, and the sprocket hub 13 and the drive disk 44 are fixed with a required number of knock pins 46, whereby the output of the carrier 32 is splined. The drive disc 44 is transmitted via the shaft 42, and is further transmitted to the sprocket hub 13 and the sprocket 14 via a thin flange portion 44 a of the drive disc 44. With the configuration of the present embodiment, the final reduction gear device 40A
Can be so compact that its outer end is approximately equal to the position of the outer end face of the sprocket 14. Other effects are
This is the same as in the first embodiment.

The third embodiment will be described with reference to FIG. FIG. 5 is a rear cross-sectional view of the final reduction gear system of the third embodiment and represents a cross-sectional view taken along the line AA of FIG. 9. In FIG. 5, the final reduction gear device 40B integrally comprises the sprocket hub 13 and the drive disk 44 which also serves as the cover in the third embodiment, and the boss portion 1 of the sprocket hub 13
3b is divided and is assembled by bolts 13c. The sprocket hub 13 (having the function of the drive disk 44) is directly spline-fitted to the spline shaft 42. Due to the above, the sprocket hub 1
3 is to be assembled at the end.

According to this embodiment, the output of the carrier 32 is transmitted through the spline shaft 42 to the sprocket hub 1.
3 is directly transmitted to the boss portion 13b, the load of output transmission is not applied to the bolt 13c for mounting the boss portion 13b.
The bolt 13c can be configured with a small strength. Also,
Since the sprocket hub 13 also serves as a cover, the number of parts can be reduced. Further, since only the sprocket hub 13 is arranged outside the cross roller bearing 12 (on the left side in the drawing), the final reduction gear device 40B is so compact that its outer end portion is substantially equal to the position of the outer end surface of the sprocket 14. Can be configured, and compactness can be realized. The other effect is the second
This is the same as the embodiment.

Next, a fourth embodiment will be described with reference to FIG. FIG. 6 is a rear cross-sectional view of the final reduction gear transmission of the fourth embodiment, which is a cross-sectional view taken along the line AA of FIG. 9. In FIG.
The final reduction gear 50A also serves as the boss portion 13b of the sprocket hub 13 as an inner race member of the cross roller bearing 12. Further, the outer case 51 includes members 55, 5
6, 57 and bolts 58 for fastening these members 55, 56, 57, and the inner races of the cross roller bearing 12 are constituted by the members 55, 56. As a result, the cross roller bearing 12 can be incorporated.

According to the above structure, the cross roller bearing 12
Since the outer races, that is, the members 55 and 56 are integrally formed with the case (member 55) of the final reduction gear transmission, the cross roller bearing 12 can be incorporated inside the outer case 51, and the final reduction gear transmission 50A can be made compact. . Other effects are the same as those of the third embodiment.

Next, a fifth embodiment will be described with reference to FIG. FIG. 7 is a rear cross-sectional view of the final reduction gear system of the fifth embodiment, and shows a cross-sectional view taken along the line AA of FIG. 9. In FIG.
The final speed reducer 50B includes the outer case 51, the members 52, 5
3, 56, 57 and these members 52, 53, 56, 5
It is composed of bolts 54 and 58 for fastening 7
3, 56 form an outer race of the cross roller bearing 12. This makes it possible to incorporate the cross roller bearing 12 and facilitates the processing of the member 52.
The carrier 32 also serves as the spline shaft 42 in the previous embodiment, and the sprocket hub 13 is directly spline-fitted to the carrier 32. As a result, the final speed reducer 50B is made more compact.

Next, a sixth embodiment will be described with reference to FIG. FIG. 8 is a rear cross-sectional view of the final reduction gear transmission of the sixth embodiment, and shows a cross-sectional view taken along the line AA of FIG. 9. In FIG. 8, the final reduction gear device 60 includes a cross roller bearing 12 between an outer case 61, a carrier 62, and a sprocket hub 63.
The outer case 61 also serves as an outer race, and the carrier 62 and the sprocket hub 63 also serve as an inner race.

With the above structure, the sprocket hub 63 is assembled to the carrier 62 with the bolts 64, so that the assembly of the cross roller bearing 12 is easily completed. Further, the carrier 62 and the sprocket hub 63 are integrally supported by the outer case 61 via the cross roller bearing 12, and power is transmitted from the carrier 62 to the sprocket hub 63. As a result, the number of parts can be reduced, and a simple and compact final reduction gear 60 can be configured.

As described above, the present invention has the following effects. (1) Since the cross roller bearings are provided in a single row, the axial length (width) of the final reduction gear transmission can be shortened and the size reduction can be achieved. (2) By using the outer race and / or the inner race of the cross roller bearing also as other members of the final reduction gear transmission, a compact final reduction gear transmission with a simple structure and a small number of parts can be configured. Thus, even if a crawler belt having an arbitrary width is provided with a predetermined gap from the beam, the outer end portion of the final reduction gear device does not project outward from the outer end of the crawler belt. (3) Since the outer race and / or the inner race of the cross roller bearing has a structure in which the roller can be incorporated, the cross roller bearing having a size corresponding to the required load bearing performance can be compactly arranged.

Although the embodiment of the bulldozer has been described above, the present invention is not limited to the bulldozer and can be carried out in a general tracked vehicle in the same manner as described above. The effect is obtained.

[Brief description of drawings]

FIG. 1 is a rear cross-sectional view of a final speed reducer according to a first embodiment of the present invention.

FIG. 2 is a rear cross-sectional view of a first modification of the first embodiment.

FIG. 3 is a rear cross-sectional view of a second alternative embodiment of the first embodiment.

FIG. 4 is a rear cross-sectional view of the final reduction gear device of the second embodiment.

FIG. 5 is a rear cross-sectional view of the final reduction gear device of the third embodiment.

FIG. 6 is a rear cross-sectional view of the final reduction gear device of the fourth embodiment.

FIG. 7 is a rear cross-sectional view of the final reduction gear unit of the fifth embodiment.

FIG. 8 is a rear cross-sectional view of the final reduction gear unit of the sixth embodiment.

FIG. 9 is a side view of a bulldozer to which the final reduction gear transmission is applied.

10 is a rear cross-sectional view of a first example of a conventional final reduction gear transmission, showing a cross-sectional view taken along the line AA of FIG.

FIG. 11 is a rear cross-sectional view of a second example of the final reduction gear device of the related art.

[Explanation of symbols]

10 ... Final reducer, 10A ... Final reducer, 10B ... Final reducer, 11a ... Inner case, 11b ... Outer case, 1
1c ... Cylindrical part, 11d ... Ring-shaped member, 11e ... Ring-shaped member, 11f ... Bolt, 12 ... Cross roller bearing, 1
3 ... Sprocket hub, 13A ... Sprocket hub, 1
3B ... Sprocket hub, 13a ... Rolling surface, 13b ... Boss part, 13c ... Bolt, 32 ... Carrier, 32b ... Shaft part, 40A ... Final reduction gear, 40B ... Final reduction gear, 4
2 ... Spline shaft, 44 ... Drive disk, 4
4a ... flange part, 45 ... bolt, 46 ... knock pin,
50A ... Final reduction gear, 50B ... Final reduction gear, 51 ... Outer case, 52 ... Member, 53 ... Member, 54 ... Bolt, 55
... member, 56 ... member, 57 ... member, 58 ... bolt, 60
… Final speed reducer, 61… Outer case, 62… Carrier, 6
3 ... Sprocket hub.

Claims (5)

[Claims] 1. A final reduction gear transmission for a tracked vehicle, wherein cross roller bearings rotatably supporting a sprocket hub are arranged in a single row, and the outer race and / or inner race of said cross roller bearings are final reduction gear. A final deceleration device characterized by being configured integrally with the above-mentioned components. 2. The final reduction gear transmission according to claim 1, wherein the final reduction gear transmission is an inner planetary type final reduction gear transmission. 3. The final reduction gear according to claim 2, wherein the length (T) from the width center of the cross roller bearing to the outer end surface of the final reduction gear is measured from the width center of the link of the crawler belt to the outer end surface of the link. A final reduction gear having a length (L) substantially equal to or less than that. 4. The final reduction gear transmission according to claim 2, wherein the outer race of the cross roller bearing is fixed, and the outer race is integrally formed with a case of the final reduction gear transmission. 5. The final reduction gear transmission according to claim 4, wherein the inner race of the cross roller bearing is divided into an inner race and an outer race, and each inner race is integrally formed with a carrier of the planetary gear and a sprocket hub. A final reduction gear characterized by being configured.