Patents Completed.
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Complete specifications of the following patents will be sent to any address in the United Kingdom upon receipt of eightpence per copy at the Sale Branch, Patent Office, Holborn, W.C.
ELECTRIC-IGN1TION SYSTEMS. Brooks and Alston.—No. 15,803, dated 7th July, 1909. The object of this invention is to provide improved means for effecting a rapid change in the strength and direction of the magnetic field of the induction coil employed, so as to obtain a better spark than is generally obtainable in ordinary ignition systems. In the illustration, a magneto machine is shown having an induction coil arranged above the armature and between the poles of the magnet. The armature is wound with two low-tension windings, one end of which is connected to earth through the armature core and the frame, while the opposite ends are connected up to a change-over make-and-break device, whereby they are arranged to be alternately placed in series with the induction coil and the external low-tension circuit. The two windings are wound in opposite directions so that the current generated in one, when in circuit, will flow in an opposite direction to that in the other. when this is in circuit. 'rhe change-over device is operated by a cam on the magneto machine and is arranged Fos that. when the current in the one winding has reached its maximum, contact is made so as to place the other winding in circuit, and, at the same time, or immediately after, the contact is broken so as to cut out the first-mentioned winding. The current is now generated by the second winding and passes through the primary winding of the coil in the reverse direction, thus reversing the magnetic field and causing an intense spark to be created.
CONTROLLING MEANS FOR MOTOR LAWN MOWERS.—Ransomes. Sims and Jefferies, Ltd., and Murdoch, No. 17,534, dated 28th July, 1909. According to this invention, the drive is effected through the medium of two sets of epicyclic gearing, one set being for the forward drive and the other set for the reverse. The present invention has particular reference to the means for bringing either of these two sets of epicyclic gearing into operation. The brake bands surrounding the gearings are adjustably secured to the frame of the mower at one end, and at the other end they are connected by means of rods to eccentrics mounted on a shaft which is adapted to be rotated in either direction by control pedals. This is effected by mounting a sprocket wheel on the shaft and by passing a chain over this wheel and connecting the two ends to the pedals, the arrangement being such that when one pedal is depressed the other one is moved forward. The eccentrics are disposed in opposite relation to one another on the shaft, so that, when one operates to apply the brake band of its respective gear, the other one is in
the disengaged position. It will, therefore, be seen that, in order to drive the lawn mower in either direction, it is only necessary to depress the pedal corresponding to the direction required. When, however, it is required to stop. the lawn mower, both pedals are released, and, consequently, the drums of the epicyclic gearing revolve idly and no drive takes place.
DETACHABLE WHEELS.—Ralph.--No. 26,380, dated 13th November, 1909. —According to this invention, the wheel is held on the usual cylindrical hub, and is prevented from rotating thereon by means of lugs formed in the hub, which engage holes in the huh of the detachable wheel. On the outer face of the detachable wheel ratchet teeth are formed, and these are adapted to be engaged by spring-controlled pawls which are carried by an annular cap. This cap, together with the pawls, is normally drawn against the outer face of the wheel by means of springs which are interposed between a portion of the annular cap and a locking cap which screws on to the hub in the usual manner. The cap carrying the spring-controlled pawls prevents the locking cap from being turned when the pawls are in engagement with the teeth of the rack, but, when it is desired to remove the wheel, these pawls can be disengaged by pulling the annular cap away from the wheel. In order to prevent the cap's flying back, a number of spring catches is provided. These catches hold the annular cap in its disengaged position, until the securing cap has been unscrewed a sufficient distance from the wheel, to permit the pawls to return to their normal position without engaging the teeth of the rack. When, however, the cap has been removed beyond this distance, the annular cap is permitted to return to its normal position. To attach the wheel, the latter is slid on to the hub, and the securing cap is screwed home ; the pawls then slide idly over the teeth of the rack.
TIRES. — Hartridge. — No. 17,563, dated 28th July, 1909.—According to this invention the tread or main portion of the tire is supported by cushions disposed between it and side flanges secured to the wheel. The side flanges are formed with circular grooves which embrace and support a number of cushions of elastic material, such as rubber, which are spaced equi-distantly around the circumference of the wheel. The tread portion of the Lire is secured to two semi-circular grooved rings, which latter embrace the inner sides of the cushion blocks. A sufficient clearance is allowed between the side flanges of the wheel and the semicircular grooved rings to allow the tread to move radially and relatively to the wheel, so far as the cushions will alto