Abstract: A rotary cutter for a tunnel boring machine or similar machine has a cutter ring mounted to a hub. The hub is mounted on a shaft. A sleeve bearing system is positioned between the hub and the shaft for supporting the hub on the shaft and allowing relative rotation. A duo-cone seal assembly is positioned between the hub and the shaft to seal out contaminants from the sleeve bearing system. An oil gallery with lubricating oil for lubricating the sleeve bearing system is provided in the shaft.

Abstract: A rotary cutter for a tunnel boring machine or similar machine has a cutter ring mounted to a hub. The hub is mounted on a shaft. A sleeve bearing system is positioned between the hub and the shaft for supporting the hub on the shaft and allowing relative rotation. A duo-cone seal assembly is positioned between the hub and the shaft to seal out contaminants from the sleeve bearing system. An oil gallery with lubricating oil for lubricating the sleeve bearing system is provided in the shaft.

Abstract: Joint assemblies are useful for connecting one structure to another structure. When the various structures deflect or bend, edge loading occurs therebetween. The subject joint assembly includes a pin positioned between a first and second structure. An insert is free floating positioned around the pin for contacting either of the first or second structures. A crown shaped surface is utilized on the insert at a substantially central location therealong. The crown shaped surface directs forces to the center of the insert to reduce edge loading.

Abstract: Joint assemblies are useful for connecting one structure to another structure. When the various structures deflect or bend, edge loading occurs therebetween. The subject joint assembly includes a pin positioned between a first and second structure. An insert is free floating positioned around the pin for contacting either of the first or second structures. A crown shaped surface is utilized on the insert at a substantially central location therealong. The crown shaped surface directs forces to the center of the insert to reduce edge loading.

Abstract: A method and apparatus for determining a tension of a track on an earthworking machine, the track having a front catenary portion and a rear catenary portion. The method and apparatus includes determining a direction of motion of the earthworking machine, determining a value of tension of the front catenary portion in response to determining the direction of motion of the earthworking machine to be in a forward direction, and determining a value of tension of the rear catenary portion in response to determining the direction of motion of the earthworking machine to be in a reverse direction.

Abstract: A track bushing for use with a track assembly of a track-type machine includes a generally cylindrical member having ends adapted for mounting in opposing end portions of a track link and a longitudinal bore extending between the ends. The inner surface of the bore defines first and second load bearing portions at each of the ends. Each of the first load bearing portions define a first conical surface tapering radially inward from each of the ends at a first angle, and each of the second load bearing portions define a second conical surface tapering radially inward from each of the first conical surfaces at a second angle. In the bushing's assembled state, the first angle is in the range of 0.09 degrees to 0.18 degrees and the second angle is in the range of -0.01 degrees to 0.01. In the bushing's free state, the first angle is in the range of 0.19 degrees to 0.27 degrees and the second angle is in the range of 0.06 degrees to 0.08 degrees.

Abstract: In a flexible step assembly (10) for a construction vehicle (14) it is desirable to provide a step assembly (10) that is durable enough to withstand impact from uneven terrain and obstacles encountered in vehicle operation and that will also provide a stable platform from which to mount and dismount the vehicle. The flexible step assembly (10) of this invention is suspended from a vehicle (14) by very durable chain assemblies (34) which have a link construction (38,64) that will enable the chain assembly (34) to lock-up to resist movement in a lateral direction upon application of an operator's weight upon a suspended step member (82).