Hand-tool system for installing blind fasteners

A hand-held tool for pulling a fastener stem while pushing against a fastener sleeve surrounding the stem to set the fastener in a workpiece, said tool comprising:

• means for gripping and pulling said stem;
• means for pushing against said sleeve while said stem is pulled;
• a housing and a piston in said housing slidably mounted with respect to said housing, and a pressure chamber formed in said housing adjacent said piston so that changes in the volume of said chamber produce relative movement of said piston and said housing, said piston and said housing being connected to said pulling means and said pushing means in a manner to cause said pulling means to pull said stem relative to said pushing means;
• a hand-operated hydraulic pump including first and second pump chambers connected to compress fluid into said piston chamber;
• and
• means for bypassing the output from said first pump chamber to a reservoir in response to a predetermined pressure in said piston chamber.

A hand-held tool for pulling a fastener stem while pushing against a fastener sleeve surrounding the stem to set the fastener in a workpiece, said tool comprising:

• means for gripping and pulling said stem;
• means for pushing against said sleeve while said stem is pulled;
• a hand-operated hydraulic pump having a low pressure mode of operation to provide pressurized fluid connected to cause said pulling means to pull said stem relative to said pushing means, said pump having a high pressure mode of operation wherein the pump provides fluid at a higher pressure than in said low pressure mode, but at a volume rate lower than in said low pressure mode;
• means for converting said pump from said low pressure mode to said high pressure mode during the setting of said fastener;
• and
• wherein said tool includes a housing and said pump includes a plunger slidably mounted in said housing, a handle lever movable by finger pressure to produce said pressurized fluid, said plunger having an annular shoulder movable in a first pump pressure chamber in said housing and an end portion having a diameter smaller than the outside diameter of said plunger shoulder, said end portion being slidable in a second pump pressure chamber in said housing, a check valve permitting pressurized fluid to flow from said pump chambers into said piston chamber while preventing flow from said piston chamber into said pump chambers, a fluid reservoir in said tool, a passage connecting said first pump chamber to said reservoir, said converting means including a valve controlling the flow through said passage, said valve being responsive to the pressure in said piston chamber to prevent flow through said passage during said low mode operation whereby fluid from both the pump pressure chambers is compressed into said piston chamber, and said valve being openable in response to a predetermined pressure in said piston chamber to thereby convert the valve to its high pressure mode wherein the pressurized fluid output from said first pump chamber is compressed into said piston chamber while the output from said second pump chamber is bypassed to said reservoir.

A hand-held tool for pulling a fastener stem while pushing against a fastener sleeve surrounding the stem to set the fastener in a workpiece, said tool comprising:

• means for gripping and pulling said stem;
• means for pushing against said sleeve while said stem is pulled;
• a hand-operated hydraulic pump having a low pressure mode of operation to provide pressurized fluid connected to cause said pulling means to pull said stem relative to said pushing means, said pump having a high pressure mode of operation wherein the pump provides fluid at a higher pressure than in said low pressure mode, but at a volume rate lower than in said low pressure mode;
• means for converting said pump from said low pressure mode to said high pressure mode during the setting of said fastener;
• and
• a reservoir connected by a passage to said pump, a check valve in said passage oriented so that liquid can flow from the reservoir in response to sufficient pressure reduction in the pump but liquid cannot normally flow through the valve to the reservoir in response to liquid pressure in the pump, said converting means includes a pilot piston movable in response to a predetermined pump pressure and connected to open said check valve to allow a portion of the pump output to flow through said passage back to said reservoir.

A hand-operated hydraulic tool for setting a fastener having a stem to be pulled into a sleeve to form a head on the end of the sleeve, the tool having a housing with a piston slidable therein, a sleeve engaging anvil connected to the piston, stem gripping jaws, a fluid reservoir and a hand pump for compressing fluid from the reservoir against said piston, the tool further including:

• a main piston pressure chamber for receiving pressurized fluid generated by said pump and causing movement of said piston with respect to said housing;
• first and second pressure chambers for compressing fluid into said piston pressure chamber;
• and
• a bypass for bypassing fluid in the first pressure chamber to said reservoir in response to the fluid pressure in said piston pressure chamber reaching a predetermined level.

A hand-operated hydraulic tool for use in setting fasteners having a stem and a sleeve, the tool having a housing with a piston slidable therein, sleeve engaging means, stem gripping means, a fluid reservoir and a pump for compressing fluid drawn from the reservoir, the tool further including:

• first and second areas with which said pump presses upon the fluid;
• a chamber into which fluid compressed by said pump with said first and second areas is delivered in a manner to cause relative movement between the piston and the housing to pull the stem with respect to the sleeve;
• and
• means for bypassing fluid from said first area to the reservoir, whereby the pump only presses upon fluid in said second area so as to deliver fluid to said chamber after the fluid pressure in said chamber reaches a predetermined level.

A hand-operated hydraulic tool for use in setting fasteners having a stem and a sleeve, said tool comprising a piston movable within a housing having a centerline, a nosepiece for pushing on said sleeve and jaws for pulling on said stem, said tool further including:

• a first pump chamber;
• a second pump chamber;
• a piston chamber;
• a plunger for pressing fluid located in the first and second pump chambers into said piston chamber;
• and
• means for bypassing output from said first pump chamber into the reservoir when the fluid pressure in said piston chamber exceeds a predetermined pressure, whereby fluid is compressed into said piston chamber by said plunger in only said second pump chamber.

A hand-operated hydraulic tool for setting fasteners having a stem and sleeve, comprising:

• a housing;
• a tubular piston slidably mounted in said housing;
• a nosepiece connected on one end of said piston;
• a drawbolt extending through said piston and fixed to said housing with the piston being slidable on the drawbolt;
• stem gripping jaws connected to a forward end of said drawbolt;
• a plunger slidably mounted in a tubular rear portion of said drawbolt and in a rear portion of said housing;
• a reservoir containing fluid;
• a first plunger chamber surrounded by a portion of said drawbolt;
• a second plunger chamber located between an inner end of said plunger and an interior rear portion of said drawbolt;
• a piston pressure chamber surrounding said drawbolt in communication with the rear of said piston;
• one or more check valves connecting said plunger pressure chambers with said piston chamber;
• a handle lever for reciprocating said plunger to compress fluid from said reservoir in said first and second plunger chambers and past said check valves into said piston chamber;
• and
• a bypass valve connected to render said first plunger chamber ineffective to compress fluid into said piston chamber with said plunger when the pressure in said piston chamber reaches a predetermined level.

A compact hand-operated hydraulic fastener setting tool for use in setting fasteners having a stem and sleeve, the tool comprising:

• a housing having a longitudinal axis;
• a handle located on said housing having a reservoir therein;
• a piston slidably mounted within said housing along said axis;
• a hand-operated plunger;
• first and second pump areas on said plunger for compressing fluid into a pressure chamber reacting against said piston;
• means for bypassing fluid from said first pump area to the reservoir, said bypass means located in said housing below said axis and along a second centerline running transverse to said housing axis and to the rear of said axis.

A method of setting a fastener having a stem and sleeve with a hand-operated fastener setting tool having a housing and a piston movable therein, sleeve engaging means, stem gripping means, plunger, and fluid in a fluid reservoir, comprising:

• reciprocating the plunger to compress fluid in first and second pump chambers;
• delivering fluid from said first and second pump chambers to a piston pressure chamber exposed to said piston;
• causing relative movement of the piston with respect to the housing to pull said stem using the fluid pressure in said piston pressure chamber;
• bypassing said first pump chamber so as to reduce the force needed to manipulate said plunger;
• and
• continuing to provide pressurized fluid to said piston chamber utilizing only said second pump chamber so as to pull said stem until the fastener is set.