US 6,655,570 B2 · Constant volume valve for a combustion powered tool

Abstract

A constant volume metering chamber and valve assembly for use with a pressurized fluid supply containing a fluid is described for use in a power fastening tool. The assembly includes a first spring-biased valve and a second spring-biased valve. There is a metering chamber having an inlet and an outlet, so that the first spring-biased valve controls the inlet and the second spring-biased valve controls the outlet. An actuator assembly operates causes the first and second spring-biased valves to move in either a first valve sequence or a second valve sequence. The first valve sequence includes engaging the first spring-biased valve with the inlet, preventing flow of the fluid from the fluid supply into the metering chamber, followed by disengaging the second spring-biased valve from the outlet, allowing flow of the fluid from the metering chamber. The second valve sequence includes engaging the second spring-biased valve the said outlet, preventing flow of the fluid from the metering chamber, followed by disengaging the first spring-biased valve from the inlet, allowing flow of the fluid from the fluid supply into the metering chamber, such that fluid is prevented from flowing freely from the pressurized fluid supply through the inlet and the outlet of the metering chamber.

Claims19

Dependent claims

A constant volume metering chamber and valve assembly for use with a pressurized fluid supply containing a fluid in a combustion-powered tool, said assembly comprising:

a housing defining a metering chamber having a plurality of ports including an inlet and an outlet;
a first spring-biased valve disposed in said housing to control fluid flow through said inlet;
a second spring-biased valve disposed in said housing to control fluid flow through said outlet;
an actuator assembly, connected to said first and second spring-biased valves and sequentially operable from a first position, in which said first spring-biased valve is open and said second spring-biased valve is closed, to a second position, in which said first and second spring-biased valves are both closed, and a third position, in which said first spring-biased valve is closed and said second spring-biased valve is open;
and
said valve assembly being configured and arranged so that a volume of fluid entering said chamber from said inlet in said first position is collected in said metering chamber, sealed within said metering chamber in said second position, and released from said metering chamber in said third position to provide a constant volume of fluid for each sequential movement of said actuator from said first position to said third position.

3 more elements

A constant volume valve assembly for a combustion powered tool having a pressurized fluid supply, the tool to be used in conjunction with a workpiece, said valve assembly comprising:

a first spring-biased valve;
a second spring-biased valve generally axially collinear with said first spring-biased valve;
a metering chamber having a constant volume, an inlet and an outlet, said inlet being controlled by said first spring-biased valve and said outlet being controlled by said second spring-biased valve;
an actuator including a control arm connected to said first spring-biased valve and to said second spring-biased valve;
a pivoting link arm that moves in response to engagement of the tool with the workpiece causing said control arm to move toward said second side, engaging said first spring-biased valve with said inlet, preventing flow of said fluid from said fluid supply into said metering chamber, then disengaging said second spring-biased valve from said outlet, allowing flow of said fluid from said metering chamber, and that disengagement of the tool from the workpiece causes movement of said pivoting link arm to move said control arm toward said first side, engaging said second spring-biased valve into said outlet, preventing flow of said fluid from said metering chamber, then disengaging said first spring-biased valve from said inlet, allowing flow of said fluid from said fluid supply into said metering chamber, such that said fluid is prevented from flowing freely from said pressurized fluid supply through said inlet and said outlet of said metering chamber.

2 more elements

Dependencies are inferred from the claim text.

Constant volume valve for a combustion powered tool

Life of this patent

Constant volume valve for a combustion powered tool

Life of this patent

Abstract

Claims19