Compensating linkage for crawler tractors

Claim 2

Compensating linkage in a track-type tractor having main frame and track roller frames pivoted adjacent their rearward ends to the main frame, comprising a lever associated with each roller frame, each lever being connected in compensating relation to a forward portion of the main frame by two links of unequal lengths, the two compensating levers being effective to provide for generally constant lateral alignment of the roller frames during relative oscillation between the roller frames and main frame, an end portion of each lever being pivoted to one of the roller frames, a shorter link being pivoted between the main frame and an opposite end portion of each lever, a longer link being pivoted between the main frame and an intermediate portion of each lever, the levers being pivoted to the respective roller frames and links by spherical joints, an equalizer support bar supporting a forward portion of the main frame, the bar extending laterally above a portion of each roller frame to support the forward portion of the main frame on the roller frames.

Claim 3

The invention of claim 1 wherein the equalizer bar is free to oscillate about a longitudinal axis of the main frame, the roller frames slidably supporting respective ends of the equalizer bar.

Claim 4

Compensating linkage in a track-type tractor having a main frame and track roller frames pivoted adjacent their rearward ends to the main frame, comprising a lever associated with each roller frame, each lever being connected in compensating relation to a forward portion of the main frame by two links of unequal lengths, the two compensating levers being effective to provide for generally constant lateral alignment of the roller frames during relative oscillation between the roller frames and main frame, an end portion of each lever being pivoted to one of the roller frames, a shorter link being pivoted between the main frame and an oppositE end portion of each lever, a longer link being pivoted between the main frame and an intermediate portion of each lever, the levers being pivoted to the respective roller frames and links by spherical joints, a pair of the links associated respectively with the two levers, being formed by a single member which is pivoted at the center of the main frame along a longitudinal axis thereof.

Claim 5

Compensating linkage in a track-type tractor having a main frame and track roller frames pivoted adjacent their rearward ends to the main frame, comprising a lever associated with each roller frame, each lever being connected in compensating relation to a forward portion of the main frame by two links of unequal lengths, the two compensating levers being effective to provide for generally constant lateral alignment of the roller frames during relative oscillation between the roller frames and main frame, an end portion of each lever being pivoted to one of the roller frames, a shorter link being pivoted between the main frame and an oppositE end portion of each lever, a longer link being pivoted between the main frame and an intermediate portion of each lever, the levers being pivoted to the respective roller frames and links by spherical joints, a pair of the links associated respectively with the two levers, being formed by a single member which is pivoted at the center of the main frame along a longitudinal axis thereof.

Claim 6

The invention of claim 3 wherein the single member is effective to support the weight of the main frame on the roller frames.

Claim 7

The invention of claim 4 wherein each lever is pivoted at one end to one roller frame, a relatively shorter link being pivoted between the main frame and an opposite end of each lever, the single member being pivoted at its ends to intermediate portions of the two levers.

Claim 8

In a track-type tractor, the combination comprising, a main frame, track roller frames arranged on the sides of the main frame, drive means providing a pivotal connection between the main frame and the roller frames adjacent one end thereof, and compensating linkage interconnected between the main frame and roller frames, the linkage including a lever pivotally connected to each roller frame and a pair of links pivotally connecting each lever with the main frame, the lengths of the links and the arrangement of the levers and links between the main frame and roller frames being selected to maintain generally constant lateral alignment of the roller frames relative to the main frame, the levers being pivoted at one end to the respective roller frames, a shorter link pivotally interconnecting the opposite end of each lever with an adjacent side portion of the main frame, a longer link pivotally interconnecting an intermediate portion of each lever with a portion of the main frame generally adjacent its longitudinal centerline, the levers being pivoted to the respective roller frames and links by spherical joints, bracing members being interconnected between the main frame and the respective roller frames adjacent the drive means, an equalizer bar pivotally supporting the main frame at a point toward its opposite end from the drive means and extending above a portion of each roller frame, the compensating linkage being interconnected between the main frame and roller frames generally adjacent the equalizer bar.

Claim 9

In a track-type tractor, the combination comprising, a main frame, track roller frames arranged on the sides of the main frame, drive means providing a pivotal connection between the main frame and the roller frames adjacent one end thereof, and compensating linkage interconnected between the main frame and roller frames, the linkage including a lever pivotally connected to each roller frame and a pair of links pivotally connecting each lever with the main frame, the lengths of the links and the arrangement of the levers and links between the main frame and roller frames being selected to maintain generally constant lateral alignment of the roller frames relative to the main frame, the levers being pivoted at one end to the respective roller frames, a shorter link pivotally interconnecting the opposite end of each lever with an adjacent side portion of the main frame, a longer link pivotally interconnecting an intermediate portion of each lever with a portion of the main frame generally adjacent its longitudinal centerline, the levers being pivoted to the respective roller frames and links by spherical joints, bracing members being interconnected between the main frame and the respective roller frames adjacent the drive means, an equalizer bar pivotally supporting the main frame at a point toward its opposite end from the drive means and extending above a portion of each roller frame, the compensating linkage being interconnected between the main frame and roller frames generally adjacent the equalizer bar.