Abstract: An apparatus has an eccentric shaft on which are mounted rolls connected to one another by flexible members in the form of a corrugated collar for end sealing of the rolls and with auxiliary members for radial sealing of the rolls. The auxiliary members are received in a radial clearance defined between the adjacent rolls which are made hollow.

Abstract: A vibration or reciprocating hydraulically driven impact tool for breaking up paving, compacting soil, or similar construction purposes. The tool employs a piston situated in a housing and configured to form (in cooperation with the housing) three chambers. One of the chambers is filled with a compressed gas which acts as a shock absorber/spring, with the other two chambers serving to drive adjacent flanges of the piston in opposite directions to provide reciprocating action. The device is constructed so that when no mechanical force is applied to the handle, the piston is at rest in its forward position (being urged there by the compressed gas), with the hydraulic forces acting upon the piston shoulders being balanced. When the handle is pushed forward, the hydralic system is altered so that unbalanced forces act on the piston flanges, causing the piston to start moving. Thereafter, a hydraulic valve system provides the desired reciprocating motion of the piston.

Abstract: A vibration or reciprocating hydraulically driven impact tool for breaking up paving, compacting soil, or similar construction purposes. The tool employs a piston situated in a housing and configured to form (in cooperation with the housing) three chambers. One of the chambers is filled with a compressed gas which acts as a shock absorber/spring, with the other two chambers serving to drive adjacent flanges of the piston in opposite directions to provide reciprocating action. The device is constructed so that when no mechanical force is applied to the handle, the piston is at rest in its forward position (being urged there by the compressed gas), with the hydraulic forces acting upon the piston shoulders being balanced. When the handle is pushed forward, the hydraulic system is altered so that unbalanced forces act on the piston flanges, causing the piston to start moving. Thereafter, a hydraulic valve system provides the desired reciprocating motion of the piston.

Abstract: The method of making holes in the soil includes driving a capsule into the oil by percussive action and filling the capsule with the soil. Then the driving of the capsule into the soil by percussive action is continued, with the soil passing therethrough. The capsule is then withdrawn from the hole, and the soil that has passed through the capsule is also removed from the hole, whereafter the soil is removed from the capsule itself. The apparatus for making holes, performing the disclosed method, comprises a capsule capable of receiving the soil therein, having an open soil intake end, its opposite end being a partly open one. The capsule incorporates a percussive mechanism.