Abstract: An impacting apparatus (10) for fracturing material includes a housing (14) and a fracturing shank (12) which is mounted adjacent the housing (14) so as to reciprocate about a pivot axis (24). The fracturing shank (12) has an impact receiving portion (28) and a sealing portion (26). The sealing portion (26) has a cylindrical sealing surface (26a) which is arranged about a longitudinal axis (26b). Such longitudinal axis (26b) is perpendicular to a radial line (33) extending from the pivot axis (24) and is inclined at a predetermined angle to a longitudinal axis (28b) extending through the impact receiving portion (28). An annular seal (16) is connected to the sealing surface (26a) and the housing (14) to obstruct the passage of material into and out of the housing (14). The seal (16) has a flexible portion (40) whose inner margin (46) lies along the radial line (33 ).

Abstract: An elastomeric seal apparatus (16) having an inner annular terminating portion (36) which is attachable to a first (12) member, an outer annular terminating portion (38) which is attachable to a second (14) member, and an annular convoluted flexible portion (40) which is disposed between the inner (36) and outer (38) terminating portions and has an inner (46) and an outer (48) margin which are respectively joined thereto. The thickness of the convoluted flexible portion (40) decreases from the relatively thicker inner margin (46) to the relatively thinner outer margin (48) in proportion to a radial distance (H) extending from the inner margin (46) to the flexible portion (40). A concentrically inner convolution (42) and a concentrically outer convolution (44) constitute the flexible portion (40) and have a relatively small (R.sub.1) and a relatively large (R.sub.2) radius of curvature.

Abstract: A track link assembly including two meshed track links, one having a narrow end received in a notch in an enlarged end in the other, aligned bores in the links, a hinge pin received in the bore for pivoting the links together, annular grooves at opposite ends of the pins, retaining rings in the grooves, recesses in one of the links about the bore therein adjacent the ends of the pin and defining shoulders substantially abutted by the retaining rings, and caps closing the recesses and having axial portions about the periphery of the respective retaining rings for preventing radial movement thereof.

Abstract: An endless track assembly for a track-type vehicle comprises a plurality of track shoes secured to an articulated chain. The links of the chain are pivotally interconnected together by pin and bushing assemblies adapted to engage a drive sprocket of the vehicle. A cushioning lug is secured to each track shoe, intermediate each pair of adjacent pin and bushing assemblies, for attenuating the noise level of the track assembly upon engagement therewith with the drive sprocket. Each cushioning lug assembly comprises a resilient cushioning block composed of an elastomeric material, a cap mounted on the cushioning block and a tensioned cable secured between the cap and a respective one of the track shoes. A ball secured to the upper end of the cable may be connected to the cap by an annular retainer formed integrally with the cap, or by a separate member secured to the cap and covered by a plug.