Patent GB-190908772-A (GB)
Title: Improvements in or relating to Horn Controlling Mechanism for Fastener Inserting Machines.
Inventor: JUSTICE PHILIP MIDDLETON
IPC: A43D69/00
Filed: 1909-04-13
Granted: 1910-04-07
Abstract: 8772. Justice, P. M., [Plant, T. G.]. April 13. Loose-nailing. - Relates to a machine with which fasteners may be inserted either, (1) singly, the machine automatically coming to rest after driving a nail; (2) in a continuous series of indefinite number; or, (3) in a series of predetermined number, a counting mechanism being provided so that the machine will stop automatically at the end of the series. The machine may be stopped at any time when driving a series of nails. The work-support is raised, to position the work, by means actuated by the driving-shaft and comprising a succession of props. It is periodically depressed to feed the work, and is finally lowered to release the work by means independent of the driving-shaft and stopping mechanism. The time taken by the props in releasing the work support is sufficient to ensure the complete insertion of any fastener that is being driven at the moment. The invention is described as applied to a machine of the usual type which drives one nail for each rotation of the main shaft. The controlling-mechanism comprises a wedge 8, Fig. 4, on a rod 10, which, when depressed, releases the clutch to stop the machine. This depression is governed by a cam on the main shaft so that it can only occur at one point in the revolution, and is effected by a spring 13 surrounding the rod and abutting against a fixed bracket 12. The wedge is raised, to start the machine, by means of a loose sleeve 22, which abuts against a fixed collar on the rod 10 and is actuated by a lift pawl 25 jointed to the starting-treadle rod 27. To prevent more than one nail from being driven after operating the starting-treadle, a cam on the main shaft is operatively connected to a lever 45, which trips the lift pawl 25. For driving nails continuously, a " series " treadle is provided, coupled to a rod 117. The two treadles are operable by one foot. Both are actuated for continuous nailing, the " series " treadle preventing the fall of the wedge-rod at the end of the first cycle, by inserting a finger 103, Fig. 8, on an horizontal rod 104 beneath a collar 106 fixed on the wedge-rod, Fig. 8. The continuous driving of nails may be stopped when desired by releasing the treadles, a spring-operated lever 148, which normally abuts against a stationary pin 147, withdrawing the finger 103. To prevent waste of nails, a counting-mechanism is provided, which may be set, to drive a selected number of nails in series, by means of a dial, Fig. 12, at the front of the machine. The counting-mechanism comprises a ratchet-wheel 126, Figs. 7 and 8, and an arm 122 coupled to the counter-dial and by this means adjusted on the ratchet-wheel. The adjustment of the arm 122 causes a back-stop pawl to be put into gear with the ratchet-wheel. To start the machine when adjusted, both treadles are depressed. The depression of the " series " treadle puts a pawl 133 into gear with the ratchetwheel, and the first turn' of the driving-shaft, which actuates the pawl 133 by a cam and suitable connexions, turns the ratchet-wheel through one tooth and removes the pin 147, which is fixed thereto, from engagement with the spring-actuated lever 148. A light spring on the rod 104 is thus permitted to insert the finger 103 to delay the stopping of the machine. Each revolution of the machine shaft advances the arm 122 through a distance corresponding to one tooth on the ratchet-wheel. In the last cycle of the series for which it has been set, the arm engages the lever 148, which then trips the finger 103 and causes the machine to stop. The pawl 133 and the back-stop pawl are taken out of gear by the subsequent release of the treadles, and the ratchet - wheel returns, under the influence of a coil spring, to its initial position with the arm 122. The series treadle may be released to stop the machine at any time, the ratchet-wheel being released thereby; the pin 147, on its return, then rocks the lever 148 to trip the finger 103. A single nail may be driven with the counter in operation by a momentary depression of both treadles. The work-support 47, Fig. 1, is mounted on a rod 48, which is adjustably and resiliently supported in, and projects below, a sleeve 52 working in guides in the machine frame. The sleeve carries rollers which are supported on the camshaped end of a prop 57 normally supported by a stop 59 and pivoted at 58 to a bracket on the frame. To position the work, a rod 64, lifted by a cam on the main shaft, actuates a bellcrank lever 62 coupled to the prop 57, which accordingly moves forward and raises the worksupport. A stop-rod 69 limits the movement of the prop 57. This is maintained in its advanced position by a second prop 74, which is placed under its heel 73 by means of a telescopic spring- extended pusher-rod 77 coupled to the bell-crank lever 62. The periodical depression of the worksupport is obtained by means of a cam on the main shaft, through a rod 101, which actuates a lever 99. The rod 48 is attached to a grip-bar 95, which passes through bearings 96 on the frame and through a grip-arm 97, which is arranged to tilt slightly upon the bar 95. Normally, this grip-bar is maintained in an horizontal position by a spring 98, which forces it against the upper bearing 97. The action of the free end of the lever 99, however, causes it to tilt and grip the bar 95, and then to move downwards through a small distance to free the work momentarily for feeding. The work-support sleeve 52 remains in its elevated position independently of the machine shaft so long as the prop 57 is in position, and the final depression of the work-support is effected by releasing the starting-treadle, and is independent of the nailing-mechanism. A cam-lever 85, normally standing in the path of a pin 83 projecting from the front portion of the telescopic pusher-rod 77, is drawn downwards by the starting-treadle in starting the machine, by means of the linkage 90, 88, 86. When the treadle is finally released, either to stop the machine or after the machine has automaticlly come to rest, the cam-lever 85 rises and shortens the pusher-rod, thus allowing the props 74, 57 to fall backwards in succession.