Patent GB-1464392-A (GB)
Title: Fluid-powered tool reciprocator
IPC: B23Q5/26
Filed: 1974-02-27
Abstract: 1464392 Fluid operated reciprocatory tools W H SANDERS 27 Feb 1974 [8 March 1973] 8992/74 Heading B4C [Also in Divisions F1 and B3] A tool reciprocator for operation with a source of pressurized fluid comprises a housing 31, a fluid operated reciprocatory piston and cylinder assembly 41, 42 within the housing, a tool engaging part 70 for engaging a tool, the part 70 being operatively connected to and adapted to be reciprocated by and with the piston 42, conduits 52, 53, for feeding pressurized fluid to the cylinder 41 and communicating with the cylinder at spaced apart locations thereon on opposite sides of the piston 42, a movable valve member 510 for controlling flow of the pressurized fluid in both the conduits and adapted when moved to one position to connect the conduit communicating with the cylinder on one side of the piston with the source of pressurized fluid and when moved to another position to connect the other conduit to the source of pressurized fluid, operating means within the housing operatively and adjustably connected to the piston 42, the operating means being adapted for moving the valve member from one to another of the positions thereof in response to and in synchronism with the arrival of the piston at a terminal point in a reciprocatory stroke thereof and on the housing and exterior thereof control means 617 for adjusting the connection between the operating means and the piston while the piston is reciprocating, in such a manner as to vary the dimension of the reciprocatory stroke of the piston and the tool engaging part reciprocated thereby. The motor is started by turning the control disc 562 of the valve 56. Fluid under pressure brought to the reciprocator housing 31 from a source of the same by the hose 543 enters into the components of the motor and the activating and pilot circuitries 50 and 60. Assuming the motor piston 42 at the moment of operating the starting valve 56 to be in the position shown in Fig. 23 it will be seen that the piston is positioned to continue a leftward movement as viewed in the drawing. The shifter valve member 510 will then be at the left end as viewed in Fig. 23 of the valve sleeve 511, thereby connecting the right end of the cylinder 41 with the pressurized fluid through the valve 51 and the passage 53. At the same time the spent fluid will exit from the cylinder 41 through the passage 52 and the shifter valve 51 to exhaust. The pilot circuitry 60 is effectual at this time to retain the shifter valve member 510 in a leftward position shown. This is so because the valve members 612L and 612R are at their normal at rest positions under the influence of a spring 614. The piston 42 continues to move in the direction indicated by the arrow 4223 approaching one end of its stroke. At this stage the traveller nut 616 engages and moves the valve member 612R leftwardly. Such movement of the valve member 612R opens the previously established pressure circuit which exerts pressure on the right end of the shifter valve member 510. The shifter valve member thus moves to the right end of its stroke. Now pressurized fluid is introduced into the passage 52 to the left side of the piston 42. This causes the piston to move to the right. Spent fluid from the right end of the cylinder 41 exits through passageway 53. By angular movement of the disc 562 one may vary the opening of the valve 56 to adjust the inflow of pressurized drive medium. The freedom of the chucked tool to rotatably float may be controllably interrupted. The operation need merely squeeze the trigger 731. Such action projects the lock pin 732 between the spline teeth of the ratchet gear 711 on the mandrel.