Patent GB-190704521-A (GB)
Title: Improvements in the Construction of Entrenching Tools.
Inventor: WOODHOUSE CLAUDE GREGORY
Filed: 1907-02-23
Granted: 1907-10-24
Abstract: 4521. Woodhouse, C. G. Feb. 23. Picks; handles.-An entrenching-tool comprising a shovel and a pick has an extensible handle, means for locking the shovel blade at right-angles to the handle with its concavity turned towards or away from the handle, or with its mean plane coincident with the T socket-bead a, and means for locking the shovel blade in the lower end of the handle. The socket a is secured to a tubular metal handle b, and is formed through its whole length or at each end c with an aperture of square, rectangular, or similar section to permit the insertion of the chisel-shaped, bifurcated, or pointed pick portion d of similar section. Between the pick d and shovel e is a cylindrical neck f of diameter equal to the shortest sides of the aperture in the head a, the length of the neck being equal to the length of the tubular socket. The neck f is provided with a shoulder g, to which the shovel blade is secured, and with four teeth i equally spaced round the neck. The tool d, e is secured to the head a by rotating the tool so that the head is held between the shoulder at the pick end of the neck f and the shoulder g. A spring tongue j, having a detent k, engages with the teeth i, and is riveted to the socket a and occupies the place of a portion of the wall of the socket which has been removed. A milled nut m surrounds the shovel end of the socket which, when screwed into the position shown in Fig. 5, forces the detent k into engagement with the tooth i. The socket h of the handle b is correspondingly fitted. Swellings or inclines n are formed on the other end of the socket to allow a tight connexion between tool and handle to be effected. Fig. 7 shows a modification in which a cam - ended lever o, pivotally mounted on the shoulder g, is adapted to engage one of four notches formed in the socket. Fig. 9 shows a modification in which a pair of studs pare spring- mounted on the shovel and are constrained against lateral displacement by the sides of the apertures in the collar q. Recesses r are provided in the end of the socket for the reception of the studs p. Figs. 9, 11, and 12 show a method of fitting a telescopic extensible handle. The tubular handle s is elliptical in cross-section and is fitted with a sliding locking-collar b. The extension tube u is circular in cross-section. The external diameter of the tube u is equal to the internal minor axis of the tube s. The external minor axis of the collar t is equal to the internal major axis of the tube s. The tube u is fitted with a collar v of length equal to the external minor axis of the collar t, so that in one angular position, shown in Fig. 11, its ends protrude through apertures w formed in the tube s sufficiently to permit them to be engaged by notches x in the locking-collar t. To telescope the tube u in or out, the collar t is withdrawn from the cotter and the tube u is next rotated through a right-angle, causing the ends of the cotter to slide along the apertures w until the cotter lies along the :major axis of the tube s, as shown in Fig. 12. The tube u can then be moved longitudinally. According to the Provisional Specification, a sliding bolt may be used to secure the tool head from rotation.