Supplementary wheel set for road vehicles

Claim 2

In a road-going vehicle having rear wheel sets supporting a chassis, the improvement of a. a tag frame supporting a tag wheel set rearwardly of said chassis, the frame having longitudinal beam means including intermediate beam portions and forward ends; b. mounting means on said chassis for mounting said tag frame beam means for longitudinal movement with respect to said chassis between a retracted position where the tag wheel set is closely adjacent the rear end of said chassis and in which said tag wheel set is elevated out of engagement with the road surface, and a second extended position spaced rearwardly of said chassis in which said tag wheel set engages the road surface and supports a portion of the chassis load, said mounting means including slide members carried by the chassis and horizontally pivotally connected to the forward ends of said beam means and further including slipway means fixed with respect to the chassis behind the slide members and including guide means confining said intermediate beam portions vertically and horizontally at the slipway, the slipway means and the slide means being mutually oriented such that the rear end of the tag frame supporting the tag wheel set is raised when the tag frame is retracted and lowered when the tag frame is extended; and c. drive means mounted on said chassis and connected to said slide members for driving said tag frame longitudinally with respect to said chassis between said retracted and extended positions.

Claim 3

A road-going vehicle as claimed in claim 1, wherein said slipway means has upper and lower guide surface means which are downwardly inclined in a direction extending rearwardly of said chassis, said tag frame beam means having said intermediate portions rearwardly and downwardly inclined at an angle which corresponds to the inclination of said guide surfaces, said inclined intermediate portions engaging said guide surface means of said slipway means during reciprocal movement between said extended and retracted positions whereby said rear end of the tag frame is downwardly directed by said slipway means in response to longitudinal movement with respect to said frame to said extended position and upwardly directed in response to movement towards said retracted position.

Claim 4

A road-going vehicle as claimed in claim 2, wherein the length of said intermediate portions of the beam means is substantially equal to the length through which said drive means drives the slide means on the chassis during longitudinal reciprocation with respect to said chassis.

Claim 5

A road-going vehicle as claimed in claim 2 wherein said guide surface means includes upper and lower guide blocks disposed within said slipway means above and below said beam means respectively, a lower surface of said guide block means forming an upper guide surface restraining said tag frame against rotation about said pivotal connection with said slide means in a direction away from the road when said frame is in the extended position and an upper surface of said lower guide block forming a lower guide surface restraining said tag frame against rotation about said pivotal connection with said slide in a direction towards the road when said frame is in the retracted position.

Claim 6

A road-going vehicle as claimed in claim 4 wherein said beam means comprises a pair of transversely spaced parallel beam members.

Claim 7

A road-going vehicle as claimed in claim 1, wherein said tag frame wheel set includes adjustable suspension means for varying the proportion of the vehicle load carried as a supplementary load by said wheel set.

Claim 8

In a road-going vehicle having rear wheel sets supporting a chassis, the chassis including two spaced parallel longitudinally extending frame members, the improvement of a. guide rail means carried by each of said longitudinally extending frame members, each of said guide rail means including upper and lower guide rail means disposed in a Spaced parallel relationship defining an angular slipway therebetween which extends downwardly and rearwardly with respect to said chassis frame members; b. a tag frame supporting a tag wheel set rearwardly of said chassis, said tag frame including a pair of longitudinally extending beam members said beam members each having a front end and the members being arranged in a parallel side by side relationship and each including an intermediate beam portion located within a slipway in sliding engagement with said upper and lower guide rails; c. drive means mounted on said chassis and connected to the front ends of said tag frame beam members for driving said tag frame longitudinally of said chassis between an extended position in which the tag wheel set is spaced a substantial distance rearwardly of the chassis and a retracted position in which the tag wheel set is closely adjacent the rear end of the chassis; d. the intermediate portion of each of said frame beam members being angularly inclined to slide within said slipways during movement of said tag frame between said extended and retracted positions, said angularly inclined portion being downwardly and rearwardly inclined with respect to said longitudinal extent of said chassis such that said beam members are directed downwardly by said slipway means in response to movement towards said extended position and directed upwardly in response to movement towards said retracted position, and e. means carried by said tag frame means for transferring a portion of the vehicle load to the tag wheel set when in said extended position.

Claim 9

In a road-going vehicle having rear wheel sets supporting a chassis, the chassis including two spaced parallel longitudinally extending frame members, the improvement of a. guide rail means carried by each of said longitudinally extending frame members, each of said guide rail means including upper and lower guide rail means disposed in a Spaced parallel relationship defining an angular slipway therebetween which extends downwardly and rearwardly with respect to said chassis frame members; b. a tag frame supporting a tag wheel set rearwardly of said chassis, said tag frame including a pair of longitudinally extending beam members said beam members each having a front end and the members being arranged in a parallel side by side relationship and each including an intermediate beam portion located within a slipway in sliding engagement with said upper and lower guide rails; c. drive means mounted on said chassis and connected to the front ends of said tag frame beam members for driving said tag frame longitudinally of said chassis between an extended position in which the tag wheel set is spaced a substantial distance rearwardly of the chassis and a retracted position in which the tag wheel set is closely adjacent the rear end of the chassis; d. the intermediate portion of each of said frame beam members being angularly inclined to slide within said slipways during movement of said tag frame between said extended and retracted positions, said angularly inclined portion being downwardly and rearwardly inclined with respect to said longitudinal extent of said chassis such that said beam members are directed downwardly by said slipway means in response to movement towards said extended position and directed upwardly in response to movement towards said retracted position, and e. means carried by said tag frame means for transferring a portion of the vehicle load to the tag wheel set when in said extended position.

Claim 10

In a road-going vehicle having rear wheel sets supporting a chassis, the improvement of a. a tag frame supporting a tag wheel set rearwardly of said chassis; b. mounting means on said chassis for mounting said tag frame for longitudinal movement with respect to said chassis between a retracted position closely adjacent the rear end of said chassis in which said tag wheel set is elevated out of engagement with the road surface and a second extended position spaced rearwardly of said chassis in which said tag wheel set engages the road surface and supports a portion of the chassis load, c. drive means mounted on said chassis and connected to said tag frame for driving said tag frame longitudinally with respect to said chassis between said retracted and extended positions, and d. said mounting means including slipway means at the rear end of said chassis, said tag frame including longitudinal beam means slidably mounted in said slipway, said slipway means including adjustable upper guide pad means operable to apply a hold-down force to said tag frame when in said extended position and releasable to facilitate withdrawal of said frame to said retracted position.

Claim 11

In a road-going vehicle having rear wheel sets supporting a chassis, the improvement of a. a tag frame supporting a tag wheel set rearwardly of said chassis; b. mounting means on said chassis for mounting said tag frame for longitudinal movement with respect to said chassis between a retracted position closely adjacent the rear end of said chassis in which said tag wheel set is elevated out of engagement with the road surface and a second extended position spaced rearwardly of said chassis in which said tag wheel set engages the road surface and supports a portion of the chassis load, c. drive means mounted on said chassis and connected to said tag frame for driving said tag frame longitudinally with respect to said chassis between said retracted and extended positions, and d. said mounting means including slipway means at the rear end of said chassis, said tag frame including longitudinal beam means slidably mounted in said slipway, said slipway means including adjustable upper guide pad means operable to apply a hold-down force to said tag frame when in said extended position and releasable to facilitate withdrawal of said frame to said retracted position.

Claim 12

A road-going vehicle as claimed in claim 8 wherein said longitudinal beam means has an elongated Z-shaped longitudinal configuration with the central angularly inclined portion thereof slidable in said slipway during movement of said beam means between said extended and retracted position.

Claim 13

A road-going vehicle as claimed in claim 8 wherein said longitudinal beam means is straight, said adjustable upper guide pad means being elevated upon retraction of said longitudinal beam means.

Claim 14

In a road-going vehicle having rear wheel sets supporting a chassis and a dump truck container body pivotably supported by said chassis, the improvement of a. a tag frame supporting a tag wheel set rearwardly of said chassis, b. mounting means on said container body for mounting said tag frame for longitudinal movement with respect to said container body between a retracted position closely adjacent the rear end of said container body in which said tag wheel set is elevated out of engagement with the road surface and a second extended position spaced rearwardly of said container body in which said tag wheel set engages the road surface and supports a portion of the container body load, c. driVe means mounted on said container body and connected to said tag frame for driving said tag frame longitudinally with respect to said container body between said retracted and extended positions.

Claim 15

In a road-going vehicle having rear wheel sets supporting a chassis and a dump truck container body pivotably supported by said chassis, the improvement of a. a tag frame supporting a tag wheel set rearwardly of said chassis, b. mounting means on said container body for mounting said tag frame for longitudinal movement with respect to said container body between a retracted position closely adjacent the rear end of said container body in which said tag wheel set is elevated out of engagement with the road surface and a second extended position spaced rearwardly of said container body in which said tag wheel set engages the road surface and supports a portion of the container body load, c. driVe means mounted on said container body and connected to said tag frame for driving said tag frame longitudinally with respect to said container body between said retracted and extended positions.