초록 ▼

A pressure regulating air valve assembly (100) for a pneumatic tool (90) is disclosed that is movable between an open position and a closed position such that the maximum pressure in the tool is limited to a predetermined value. The valve assembly include a fitting (110) with a central aperture (112

A pressure regulating air valve assembly (100) for a pneumatic tool (90) is disclosed that is movable between an open position and a closed position such that the maximum pressure in the tool is limited to a predetermined value. The valve assembly include a fitting (110) with a central aperture (112) and an upper portion (114). A valve plate (130) is disposed in the fitting, and a collar (140) having an aperture (146) is retained in the fitting. A proximal end of a tubular piston (120) extends through the aperture, and a spring (118) biases the piston toward an open position. When the pressure in the hand tool exceeds a predetermined value, the pneumatic force on a distal annular head (126) of the piston urges the piston toward the valve plate (130), closing the valve. The valve plate may include a centering portion (134) and an elastomeric panel (136).

대표청구항 ▼

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 1. A pressure regulating valve assembly for a pneumatic hand tool having an air inlet channel, the pressure regulating valve assembly comprising: an inlet fitting having an inlet aperture

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 1. A pressure regulating valve assembly for a pneumatic hand tool having an air inlet channel, the pressure regulating valve assembly comprising: an inlet fitting having an inlet aperture adapted to receive an air line providing a source of pressurized air, the inlet fitting including a tubular portion having an inside diameter; a valve member slideably disposed in the inlet fitting, the valve member including a square centering portion having a diagonal dimension slightly smaller that the inside diameter of the inlet fitting tubular portion; a collar retained in the inlet fitting, the collar having a piston aperture; a piston having a tubular proximal end that slidably engages the piston aperture in the collar, and an annular head portion, the piston defining an axial channel therethrough, the piston being movable between an open position and a closed position; a biasing member that biases the piston toward the open position; wherein, when the piston is in the open position a fluid flow path through the inlet aperture and through the axial channel in the piston is open, and when the piston is in the closed position the piston abuts the valve member such that the fluid flow path is closed. 2. The pressure regulating valve assembly of claim 1, wherein during use air pressure from the source of pressurized air produces a force on the piston in the opposite direction from the bias from the biasing member. 3. The valve assembly of claim 1, wherein the collar is lockingly retained in the inlet fitting. 4. The valve assembly of claim 3, wherein the collar is retained by a C-shaped retaining ring. 5. The valve assembly of claim 1, wherein the proximal end of the piston is lockingly retained in the collar with a retaining ring. 6. The valve assembly of claim 1, wherein the valve member includes an elastomeric panel positioned to engage the piston when the piston is in the closed position. 7. The valve assembly of claim 1, wherein the collar comprises a circumferential outer groove adapted to receive an o-ring for sealingly engaging the upper portion of the inlet fitting, and a circumferential inner groove adapted to receive an o-ring for sealingly engaging the proximal end of the piston. 8. The valve assembly of claim 1, wherein the inlet fitting is adapted to engage a quick-release mechanism. 9. The valve assembly of claim 1, wherein the annular head portion of the piston includes an o-ring adapted to sealingly engage the air inlet channel in the hand tool. 10. A valve assembly for a pneumatic tool, the valve assembly comprising: an inlet fitting having an inlet aperture adapted to engage a source of pressurized air, and a tubular upper portion; a valve plate slideably disposed in the tubular upper portion of the inlet fitting, the valve plate including a square centering portion having a diagonal dimension slightly smaller than an inside diameter of the upper portion of the inlet fitting; a collar retained in the inlet fitting, the collar having a center aperture; a piston having a tubular proximal portion and a distal annular head portion, wherein the proximal portion extends through the collar center aperture, the piston defining an axial channel therethrough; a biasing member that exerts a biasing force on the piston away from the valve plate; wherein, when the air pressure in the pneumatic tool exceeds a predetermined value the pneumatic force on the annular head portion of the piston overcomes the biasing force on the piston such that the piston moves to engage the valve plate. 11. The valve assembly of claim 10, wherein the collar is lockingly retained in the upper portion of the inlet fitting. 12. The valve assembly of claim 10, wherein the proximal end of the piston is lockingly retained in the collar with a retaining ring. 13. The valve assembly of claim 10, wherein the valve member includes an elastomeric panel positioned to engage the piston when the piston is in the closed position. 14. A pneumatic hand tool comprising: a handle having an air inlet channel therethrough; a valve assembly releasably disposed in the air inlet channel, the valve assembly including: an inlet fitting having an inlet aperture adapted to engage a source of pressurized air, and a tubular upper portion; a valve plate slideably disposed in the tubular upper portion of the inlet fitting, the valve plate including a square centering portion having a diagonal dimension slightly smaller than an inside diameter of the upper portion of the inlet fitting; a collar retained in the inlet fitting, the collar having a center aperture; a piston having a tubular proximal portion and a distal annular head portion, wherein the proximal portion extends through the collar center aperture, the piston defining an axial channel therethrough; a biasing member that exerts a biasing force on the piston away from the valve plate; wherein, when the air pressure in the pneumatic tool exceeds a predetermined value the pneumatic force on the annular head portion of the piston overcomes the biasing force on the piston such that the piston moves to engage the valve plate. 15. The valve assembly of claim 14, wherein the collar is lockingly retained in the upper portion of the inlet fitting. 16. The valve assembly of claim 14, wherein the proximal end of the piston is lockingly retained in the collar with a retaining ring. 17. The valve assembly of claim 14, wherein the valve member includes an elastomeric panel positioned to engage the piston when the piston is in the closed position.