Patent · US Expired

Paving breaker

US4483402A · kind A · utility

13Cited by
5References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 1, 1981
Grant dateNov 20, 1984
Priority date
Expiry dateDec 1, 2001

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB25D9/16
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A paving breaker for the construction industry of the type having a vibrating moil point or tool steel impacted by a pneumatically reciprocated piston including a double walled cylinder slidably receiving the piston designed so that the space between the inner and outer walls of the cylinder forms a passageway for delivery of piston return air to the lower cylinder chamber and the space also forms an accumulator for air compressed by the piston during the lower part of its power stroke. In one embodiment an outer cylinder sleeve is mounted on an elastomeric member surrounding an inner cylinder sleeve, and is free to reciprocate a limited distance in the housing to partly balance the reaction forces of the piston. This double walled cylinder is surrounded by rectangular polyurethane covers that form an air exhaust space around the cylinder so that exhaust air assists in cooling the cylinder. Air is ported to the opposite ends of the cylinder by a self guiding valve member that has easily machined expansion grooves on opposite sides of a metering land and an annular guide stem that is slidably mounted in a bore in a lower valve block member mounted at the top or backhead of the pavin…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.