Patent GB-190801979-A (GB)
Title: Improvements in or relating to Apparatus for Igniting Miner's Safety Lamps or the like, especially suitable for use in the Underground Workings of Mines and in like Places.
Inventor: HAILWOOD ERNEST ARTHUR
Filed: 1908-01-29
Granted: 1909-01-21
Abstract: 1979. Hailwood, E. A. Jan. 29. Miners' s a f e t y lamps. - Electric igniting - apparatus for miners' lamps of the type described in Specifications No. 21,009, A.D. 1905, and No. 25,258, A.D. 1906, is constructed with means whereby the lamp in the lamp chamber may be automatically freed from any obstructions or tampering - devices, or the lamp may be automatically displaced from its contacts in case obstructions a r e present, the means consisting of revolving, sliding, or other plates, rods, disks, &c. operated by movement of the door of the lamp chamber &c. The means is referred to as a "sweep," and the "sweep" may be fixed while the lamp moves. Suitable electric contacts are used. As shown in Fig. 1, a sweep S, which may be a plain bar or a bar shaped somewhat to the lamp, is attached to a ring S<2> preferably arranged on balls S<3> and placed around the base-ring K, which may be mounted on an insulated bush N<1> connected by a ring N<3> and screw N' to the electric chamber C. The lamp chamber A is fitted with a hinged door D having an observation glass 0, and with a revolving door B, which carries a cap E connected to the door B by a bayonet-joint connexion and a bolt or lock. The door B is fitted with observation glasses O<2> with a gauze O<3> between them. To allow exploded gases to escape from the chamber A, spaces E' are formed in the cap E. To allow gases to escape from the chamber C, its apertured door D<1>, which is mounted on balls D', is closed by a semicircular plate D<3> which causes the gas to move tortuously. The electric circuit is completed by the movement of the door B and cap E, the cap being provided with a cam-groove F, Figs. 1 and 6, which operates a roller F<1> on a bracket G<3> constrained to move steadily over guidebars G<5>. The bracket G<3> carries an insulated spring contact G<2>, which finally meets a contact G<8> of an insulated push-piece G carried by a spring-controlled sleeve G', and the sleeve G<1> and bracket G descend together, the push-piece G finally contacting with the lamp after a semicircular guard L has been rotated by a rack R on the cap E and gear-wheels R', R<2>. The bracket G<3> also carries a spring contact, not shown, which contacts with a spring or other contact on the chamber A. A gap G<10> is formed in the cam-groove F to allow the bracket G3 to be passed through, and a tube H conducts a wire or wires to the contacts G. The guard L is moved around with the sweep S. Suitable buffer springs or stops may be arranged to limit the motion of the chamber B. In a modification, a shaped strip, or a part which surrounds half the lamp, is attached to the inner lamp chamber which is rotated by a handle. In a further modification, the lamp chamber and sweep are fixed, and the revolving door is provided with a rack which operates a train of gear-wheels causing the lamp base to revolve and complete one set of contacts, a second set of contacts carried by the train of wheels being also caused to connect when the door is closed. As shown in Fig. 4, the sweep S is adapted to be raised and lowered by a groove M in the revolving chamber A, which engages a stud M<1> on the sweep. The groove M is protected by a guard S<1> on the sweep. Rotation of the sweep S may be prevented by a square guide-bar M<2>. The sweep either removes obstacles when ascending, or raises the lamp off its base. In a further modification, as shown in Fig. 8, the sweep is formed of two or more shaped members S, which are rotated by the door owing to a sliding connexion between lugs T<2> of the members S and jaws T' on the door. The members S are moved outwards against recesses in the lamp chamber when the door is opened, and inwards to complete the circuit, after the members S have cleared the chamber, by cam-grooves F<x> which engage projections T<3> on the members. The circuit is completed by spring contacts Q, Q<2>, the former touching the lamp and the latter being closed by ring projections T<4>. The application to a rectangular form of apparatus is effected by causing a sliding door of the electric chamber to actuate a gear-wheel carrying a sweep which is revolved in the cylindrical lamp chamber. In a further modification, a sweep of semi-cup shape provided with a switch guard is actuated by a revolving door to which it is connected by a screwed rod, which also passes through a sleeve carrying a push-operating device. The lamp may be steadied during the sweeping by a spring - pressed ballpointed plunger. The apparatus may be modified by causing the lamp and sweep to move in opposite directions, or the sweep may be attached to a separate series of levers, cords, &c. operated manually or automatically.