TRIANGULAR TRACK RESILIENT BOGIE SUSPENSION

• US 3,774,708 A
• Filed: 12/27/1971
• Issued: 11/27/1973
• Est. Priority Date: 12/27/1971
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Kenneth E. Wehr, Robert J. Purcell
• Inventors: Purcell, Robert J., Wehr, Kenneth E.
• Primary Examiner(s): Johnson, Richard J.
• Application Number:
  US05/212,396
• Time in Patent Office: 701 Days
• Field of Search: 305/29,25,31,32,22,27 180/9.62,9.54,9.5
• US Class Current: 180/9.5
• CPC Class Codes: B62D 55/10 Bogies; Frames track-tensioning means B62D55/30
• CPC Class Codes: B62D 55/108 with mechanical springs, e.g. torsion bars

Abstract

An assembly for supporting and driving a vehicle with a crawler track has the track chain engaged on a pair of spaced apart idler wheels and a drive sprocket situated between the idlers and upwardly therefrom whereby the chain is maintained in a triangular configuration with the sprocket and drive elements situated well above the abrasive conditions at ground level, the entire assembly being oscillatable relative to the associated vehicle. To provide good resiliency and recoiling ability under high speed, heavy duty conditions each idler is mounted on one leg of an angled member which is pivoted to a fluid shock absorbing cylinder attached to an oscillatable track frame. Resilient means acting on the other leg comprises compression pads exhibiting a progressive spring rate whereby the idler may shift upwardly or backwardly as necessary to absorb shocks and reduce wear. Pairs of load carrying track rollers are mounted on bogies pivoted to the other leg of the angled member. In an alternative embodiment the track roller bogies are pivoted directly to the oscillatable track frame.

Claims

1. A supporting and driving assembly in a vehicle having a vehicle frame and a drive shaft, comprising:

a. a track frame mounted to the vehicle frame and having first and second ends;

b. first and second idlers associated with the first and second track frame ends respectively, the first idler being movable toward and away from the second idler;

c. a drive sprocket associated with said drive shaft and positioned between the ends of the track frame and above the idlers;

d. a track chain encompassing the idlers and drive sprocket and in driven engagement with the drive sprocket;

e. means for urging the first idler away from the second idler to maintain track tension, meanwhile allowing movement of the first idler toward the second idler to allow recoil of the first idler;

f. a crank member having an intermediate point pivotally secured to the first end of the track frame and having first and second legs extending from said intermediate point, with the first idler associated with the first end of the track frame being mounted on said first leg of the crank member;

g. roller means mounted to the second leg of the crank member and in engagement with the track chain, wherein said roller means mounted to the second leg comprise a bogey pivotally mounted on the second leg of the crank member, and track rollers rotatably mounted on the bogey and engaging the track chain; and

h. a link pivotally mounted to the track frame inwardly of the first and second idlers, and roller means mounted to the link and in engagement with the track chain.

2. The assembly of claim 1 wherein said roller means mounted to the link comprise a bogey pivotally mounted to the link, and track rollers relatively rotatably mounted on the link bogey and engaging the track chain.

3. The assembly of claim 2 wherein the track frame is pivotally mounted to the vehicle frame.

4. The assembly of claim 3 wherein the track frame ends extend forwardly and rearwardly, and wherein, relative to the track frame-vehicle frame pivot point, the forwardly extending end of the track frame is relatively long, and the rearwardly extending end of the track frame is relatively short.

5. The supporting and driving assembly in a vehicle having a vehicle frame and a drive shaft, comprising:

a. a track frame mounted to the vehicle frame and having forwardly and rearwardly extending ends;

b. a first crank member having an intermediate point pivotally secured to the forwardly extending end of the track frame and having first and second legs extending from said intermediate point;

c. a first idler mounted on the first leg of the first crank member;

d. first roller means mounted on the second Leg of the first crank member;

e. a second crank member having an intermediate point pivotally secured to the rearwardly extending end of the track frame and having first and second legs extending from said intermediate point;

f. a second idler mounted on the first leg of the second crank member;

g. second roller means mounted on the second leg of the second crank member;

h. the first crank member, and the first idler therewith, being movable toward and away from the second idler;

i. a drive sprocket associated with said drive shaft and positioned between the ends of the track frame and above the idlers;

j. a track chain encompassing the first and second idlers and drive sprocket, and in driven engagement with the drive sprocket, and engaged by the first and second roller means; and

, k. means for urging the first crank member and first idler therewith away from the second idler to maintain track tension, meanwhile allowing movement of the first crank member and first idler therewith toward the second idler to allow recoil of the first idler.

6. The assembly of claim 5 wherein the first and second roller means comprise first and second bogeys pivotally mounted to the second legs of the first and second crank members respectively, and track rollers rotatably mounted to the first and second bogeys and engaging the track chain.

7. The assembly of claim 6 and further comprising first and second links pivotally mounted to the track frame inwardly of the first and second idlers, and third and fourth roller means mounted to the first and second links respectively and in engagement with the track chain.

8. The assembly of claim 7 wherein the third and fourth roller means comprise third and fourth bogeys pivotally mounted to the first and second links respectively, and track rollers rotatably mounted to the third and fourth bogeys and engaging the track chain.

9. The assembly of claim 8 wherein the track frame is pivotally mounted to the vehicle frame.

10. The assembly of claim 9 wherein, from the track frame-vehicle frame pivot point, the forwardly extending end of the track frame is relatively long, and the rearwardly extending end of the track frame is relatively short.

11. A supporting and driving assembly in a vehicle having a vehicle frame and a drive shaft, comprising:

a. a track frame mounted to the vehicle frame and having first and second ends;

b. first and second idlers associated with the first and second track frame ends respectively, the first idler being movable toward and away from the second idler;

c. a drive sprocket associated with said drive shaft and positioned between the ends of the track frame and above the idlers;

d. a track chain encompassing the idlers and drive sprocket and in driven engagement with the drive sprocket;

e. means for urging the first idler away from the second idler to maintain track tension, meanwhile allowing movement of the first idler toward the second idler to allow recoil of the first idler;

f. a crank member having an intermediate point pivotally secured to the first end of the track frame and having first and second legs extending from said intermediate point, with the first idler associated with the first end of the track frame being mounted on said first leg of the crank member;

g. and further comprising resilient means arranged for compression between the crank member and the track frame upon pivoting of the crank member.

12. The assembly of claim 1 and further comprising resilient means arranged for compression between the link and the track frame upon pivoting of the link.

13. The assembly of claim 10 and further comprising resilient means arranged for compression between the first and second crank members and the track frame upon pivoting of the first and second crank members.

14. The assembly of claim 13 and further comprising resilient means arranged for compression between the first and second links and the track frame upon pivoting of the links.