Patent GB-191224107-A (GB)
Title: A Means of Obtaining a Periodic Reciprocating Motion from a Continuous Rotary Motion.
Inventor: LING-BEVINGTON MARTIN
IPC: F16H27/02
Filed: 1912-10-22
Granted: 1913-07-10
Abstract: 24,107. Bevington, M. Ling-. Oct. 22. Link-work.-Relates to a device for converting a continuous rotary motion into a reciprocatory motion having a pause of predetermined duration at either one or both ends of its travel or stroke. The device is stated to be adapted for operating the charging- piston in a two-strokecycle internal-combustion engine such as is described in Specification 22,722/11, [Class 7 (ii), Internalcombustion engines, Arrangement &c. of]. To obtain the desired effect, a crank-shaft driving the reciprocatory member has an arm carrying a radially movable pin which engages a radial slot in a constantly rotating driving-member mounted out of alinement with the crank-shaft. The drive is only transmitted when the pin has been brought to an eccentric position in relation to the driving-member, and ceases, providing the pause in the reciprocatory motion, when the pin occupies a concentric position in relation to the driving-member. The position of the pin is determined by a cam rotating in geared relation to the driving-member. An arrangement for obtaining a reciprocatory motion having a predetermined pause at one end only of its stroke is shown in Figs. 1, 2, 4, 9, 20, 33, and 34. The member 1 to be reciprocated is connected to a block 2 slidable in guides 3, and having a transverse slot with a slide block 4 whereby it is operated by a crank-shaft 7 rotatable in fixed bearings 8. To the crank-shaft 7 is fixed an arm 9 slotted at one end to carry a slide block 10 and bored through to the other end to accommodate other members, as shown in Fig. 4, enabling the position of the block 10 in the slot to be varied. A projecting pin 12 with a sleeve 13, eccentrically carried by a disk 11 rotatably mounted in the slide block 10 engages a radial slot 28 in a constantly-rotating disk 27. The disk 27 is geared to a driving-shaft 35, which also carries a cam 34 acting through intermediate members to control the position of the slide block 10 in the slotted member 9. The gearing is arranged so that the rotations of the disk 27 are a simple multiple of those of the driving-shaft 35. The inner end of the slot in the member 9 is recessed, as shown in Fig. 34, to hold the pin 12 at the inner limit of its movement so that its centre and the centre of the disk 11 lie on a radius of the axis N about which the arm 9 rotates. In this position, the axis of the pin 12 coincides with the axis of the rotary disk 27, the disk 27 thus rotates without transmitting motion to the crank-shaft 7 until the cam 34 operates to move the slide block 10 with the disk 11 and pin 12 towards the outer end of the slotted member 9, this operation synchronizing with suitable alinement of the slot 28 and being rendered practicable by the eccentric disposition of the pin 12. The crank-shaft 7 is thereupon rotated, causing the member 1 to make a single forward and return movement during a rotation of the disk 27. The cam 34 having meantime gone out of action, the pin 12 has become again concentric upon the completion of a rotation of the disk 27, and a pause in the movement of the reciprocatory member ensues until the cam 34 again comes into operation. The intermediate members whereby the cam 34 controls the position of the slide block 10 in its slot comprise an arrangement of intermediate levers 33, 32, 29 and a radially slidable plunger device 19 shown in Fig. 4. The slide block 10 is provided with a cylindrical rod 14 having a collar 15, upon which a spring 21 acts normally to retain the block 10 at the inner end of the slot. The block is, moreover, locked in this position by lugs 16 on the rod 14 which cannot pass through corresponding axial grooves in a rotary cylinder 17 until this is rotated into suitable alinement. When the plunger 19 is pushed into its cavity by the cam 34 in opposition to a spring 22, an arm or bracket (not shown) attached to the plunger and formed with an inclined slot engaged by an arm on the cylinder 17, brings the grooves in the cylinder into alinement with the lugs 16, releasing the slide block 10, which at the same time is pushed outwards by means of a shoulder R on the plunger 19. To obtain a pause or interval at each end of the stroke of the reciprocatory member, the form of the disk 27 is modified, as shown in Fig. 29. The radial slot 28 opens into an annular groove 40 into which the pin 12 on the arm 9 passes towards the end of the outward stroke of the member 1. A pause then ensues until, after a complete rotation of the disk 27, the radial slot 28 again comes opposite the roller 12, whereupon the return stroke commences and the roller 12 passes down the slot to its original concentric position. The return movement is rendered positive by an arm 41 normally held by a spring against a lug 43 on the disk 27. Towards the completion of the idle rotation of the disk, the roller 12 moves the obstructing arm 41 against another lug 44 on the disk, in which position a part 42 of the arm 41 forms a radial extension of one side of the radial slot 28, compelling the roller to pass into the radial slot, thereby commencing the return movement. The reciprocatory slide-member 2 is held at the outward end of its movement by means of a spring- controlled crank-like device 49 upon a shaft 50, which engages the recessed end of an extension 45 of the block 2 passing through the guide 3. The shaft 50 is rocked to release the member 2 for its return movement by means of a cam 38 upon the rotating disk 27 acting upon an arm 52 upon the shaft 50. The pause at the inner end of the reciprocatory movement is effected in the manner first described.