GB1018470A - Method and apparatus for increasing the number of strokes performed by pneumatic piston cylinder devices in a given period of time - Google Patents

Abstract

1,018,470. Stapling and nailing device. SENCO PRODUCTS Inc. Nov. 3, 1964 [Nov. 5, 1963], No. 44763/64. Heading B4C. A pneumatic fastener applying device, such as for stapling or nailing, comprises a piston movable through working and return strokes under the control of manually-actuated valve means 20, 22, 24 and pneumatic means 42, 44, 46 for initiating and sustaining repetitive operation of the piston so long as the control means is actuated. The control means is in the form of a piston 22 adapted to unseat a ball valve 24 upon actuation of a trigger 20 so as to allow compressed air to flow from a reservoir 18 through the valve 24 and operate a further piston firing valve which then admits air into a cylinder 10, Fig. 2 (not shown) to drive the piston 12 on its working stroke In order to provide for continuous operation, the compressed air, when the piston 12 reaches its lower position, flows through a port 36 into an annular chamber 37 and then through a port 42 to act on a piston 44. Movement of the piston 44, via a lever 46, moves the trigger downwardly against the pressure of the operator's hand so that momentarily the valve 24 is closed and permits the piston 12 to return. Directly the port 36 is closed by the latter piston, the piston 44 returns so as to allow the valve 24 to be opened and initiate another working stroke. If it is desired to use the tool for " single-shot " working, the piston 44 may be moved by some manual means in order to close the port 42. In the modification shown in Fig. 4, the device is mounted on a pivot 56 and maintained in a raised inoperative position by means of a spring 53. In operation, upon actuation of a foot-controlled valve 60 air is fed, via a pipe 58 and valve 68, to act on a ram 55 which pivots the device so that the driver guide 35 abuts a support 64, at the same time the air actuates the driver piston 12 as previously described. At the end of the working stroke, air passes through the port 42 and pipe 66 so as to act on the valve 68 and so allow the piston 12 to return; the function of the device is then similar to the previous embodiment.