Did You Know...
...In 1790, the cost to obtain a patent was between $4 and $5.
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 7536943 | Valve and auxiliary exhaust system for high efficiency steam engines and compressed gas motors A steam engine with improved intake and exhaust flow provided by separate pairs of intake and exhaust ports located at both ends of a steam drive cylinder. A slide valve located adjacent to the drive cylinder provides for timed sealing of intake and exhaust ports du... | 05/26/2009 |
| 5979291 | Hydraulically operated percussion hammer A hydraulically operated percussion hammer comprising a percussion piston that reciprocates by means of the pressure of the pressure fluid, a main valve that is controlled by the position of the percussion piston and that guides the pressure fluid to the ... | 11/09/1999 |
| 5064005 | Impact hammer and control arrangement therefor Hydraulic hammers are normally controlled by an actuating valve which controls the flow of fluid from a source of pressurized fluid to the hydraulic hammer. During certain periods of operation, the actuating valve totally blocks communication of fluid to ... | 11/12/1991 |
| 4715265 | Process and apparatus for vibratory operation of a working piston, in particular for active working tools The working piston (15) in the cylinder (1) is acted upon by pressure fluid only on one side, while the return movement of the piston is produced by reaction forces (R). The pressure fluid feed and the pressure fluid discharge are effected by way of separ... | 12/29/1987 |
| 4509669 | Sound-dampened driving apparatus for fasteners The present invention relates to a sound-dampened driving apparatus for fasteners wherein a main valve member is arranged above a working cylinder of the apparatus and movable within a cylindrical bore. When the main valve member is in its lower at rest p... | 04/09/1985 |
| 4342255 | Oscillator actuated hydraulic impulse device An oscillator actuated hydraulic impulse of the type including a spool valve actuated by an alternating signal from an oscillator to switch the hydraulic pressure in a double acting cylinder in order to cause reciprocating motion of a piston which strikes... | 08/03/1982 |
| 4240326 | Hydraulic vibration exciter and method of cooling thereof A hydraulically operated vibration exciter for a vibrating compactor of the kind comprising a piston in a cylinder, the piston and cylinder being arranged to move to and fro relative to each other, a source of liquid under pressure, a pressure line connec... | 12/23/1980 |
| 4168655 | Power output control system for vapor engine A vapor engine including a cylinder in which a piston reciprocates and having an inlet valve in the cylinder head which is driven from its seat by the piston as it approaches the cylinder head. The time at which the valve is driven from its seat does not ... | 09/25/1979 |
| 3974885 | Pneumatic percussive power tool A power tool having a cylindrical housing accomodating a hammer and a two-step defining piston head, with central, rear and supplementary chambers in the housing, said head and supplementary chambers being constantly intercommunicated through a passage pr... | 08/17/1976 |
