Patent GB-190727140-A (GB)
Title: Improvements in Apparatus for Igniting Miners Safety Lamps, especially suitable for use in the Underground Workings of Mines and in the like places.
Inventor: HAILWOOD ERNEST ARTHUR
Filed: 1907-12-09
Granted: 1908-12-09
Abstract: 27,140. Hailwood, E. A. Dec. 9. Miners' and like safety lamps are ignited underground electrically by enclosed apparatus of the kind described in Specifications No. 21,009, A.D. 1905, No. 25,258, A.D. 1906, and No. 12,274, A.D. 1907, the forms of apparatus being of the type in which relatively movable inner and outer lamp chambers are employed. The chief features of the invention consist in arranging guard-plates to render the apparatus safe by protecting the contacts &c., in arranging that the electric circuit is closed only by an article about the same size or weight as a lamp, in various forms of switchactuating means, in the construction of lamp baserings, and in the use of a third detachable chamber which serves to protect the lamp. As shown in Fig. 1, a sliding inner chamber A is used, which, when the lamp is placed on its base A<1>, is raised within an outer chamber B by means of a rack J actuated by a pinion J<2>. As the chamber A is raised, doors or guards D, D<1> are automatically opened by springs D', when sloping recesses B<2> in an enlargement B<1> of the chamber B are reached, and when the chamber A is further raised, the top ring or eye of the lamp closes a simple contact; or, as shown, the eye of the lamp is adapted to enter a sliding ring G<1> and to press on a sliding push C<3>, which, by means of a strong spring, moves an insulated contact C<1>, arranged in a flange ring G and normally depressed by a weak spring. The push C<3> is connected to a contact C<2>. When the lamp top contacts with the ring G<1>, the contacts C', C<2> are pressed together, but if the eye-bolt is not present, the contacts C', C' do not meet. The circuit may also be provided with contacts C<8>, C<9> arranged in a spring-controlled sliding ring F of about the same diameter as the lamp, which is raised by the lamp but is not acted on by a smaller article ; if a larger article is used the contacts C<8>, C<9> are closed but not the contacts C<2>, C<3>. The circuit also includes contacts C<7>, C<6>, C<5>, C<4>, the lastmentioned being carried by the rack J. After the contacts C<4>, C<5> meet, the contact C<6> is raised against the action of a spring to meet the contact C<7>. The chamber A is closed by a hinged door H, and the chamber B by a door H<2>, which is raised by a pinion J7 in advance of the rise of the chamber A. The rack J, or the rack of the door H<2>, may be automatically locked by spring-controlled lock J<6>, which is withdrawn by a key with a left-hand thread, or by an electro-magnet in the igniting- circuit. The chamber B<1> is provided with a removable cap E, which may be attached by a bayonet-joint and locked by a hasp and padlock. A casing B<4> may be used to protect the electric wires. In a modified form, the chamber A is adapted to be rotated as it ascends by a stud engaging an inclined recess in the outer chamber, and the door H is hinged to the side of the chamber A. The rack J in this case carries a guard-plate for the aperture in the chamber B. The chambers may be moved by levers, cords, wires, &c. The gearing for actuating the chambers may operate a dynamo or a magneto machine. As shown in Fig. 9, a sliding door D replaces the hinged doors D, D', Fig. 1, the door being moved aside as the chamber A is raised by a cord D<5>, which passes over pulleys D<6> and is actuated by the rising of the chamber. In this form, a lamp base-ring is used consisting of a fixed segment U and a sliding ring U<1>, which draws the lamp against the segment U by means of a screw U<2> and a threaded block U<3>. When the lamp is securely clipped between the parts U, U<1>, a contact carried by the ring U<1> engages a contact fixed near the ring, or the parts U, U<1> may force two spring-separated contacts together. In another form, rings U, U<1>, Fig. 13, are connected by levers U<6> and links U<7> to a push-bar U<8>, which may be connected to the operating - mechanism. Terminals C<17>, C<18> are joined when the clips U, U<1> grip the lamp. The clips may be formed with a flange adapted to bear on the lamp chamber to form a gas-tight joint. In a further modification, Fig. 3, the chamber A is formed with a closed top D<8>, having an aperture L<1>, and is provided with an apertured circular guard-plate L, or a semicircular plate, arranged to allow a contact C<3> to penetrate the aperture L<1> at the proper time. The contact C<3> may be arranged on the cover E, or, as shown, on the crown D<8>, in which case the outer chamber B is revoluble, and a switch composed of parts C<1>, C<2>, C<3> separated by springs of different strengths, is actuated by a cam M on the cover E. Contacts C<9>, C'‹ near the switch are arranged to be connected only when an article of the proper height is in the chamber A. The chamber A is formed with a locking-recess J<8> which receives a spring stop J7. The switch shown in Fig. 21 may also be employed. In this case, the contact C<3> is normally held raised by a spring V, and is depressed to contact with the lamp by a plunger V<2>, arranged to slide in the contact C<3> and move the contact C<3> by means of a spring V<1>. The plunger V<2> is actuated by an arm V<3> carrying a roller V<4>, which is depressed by a cam, and the arm V<3> may be guided by a pillar V<8> surrounded by a spring V<9>. The plunger V<2>. carries a sleeve V<7>, which surrounds the plunger C<3> and reduces the effect of side strains, the sleeve V<7> being guided by a guide G<4>. The arm V<3> carries a contact C<9> similar to the contact C<9> shown in Fig. 3, and for a similar purpose. A spring-raised lamp dish N, Fig. 3, is arranged to be depressed by an article about the weight of the lamp in such a manner as to complete the circuit between two contacts C<12>, C<13> provided with antifriction wheels Q, which engage a contact-piece C<11> on a bar P<3> attached to the dish N. If an article heavier or lighter than a lamp is present, the contacts C<12>, C" are not joined. In a similar weight-actuated switch, the lamp is suspended by a hook and eye by a spring-controlled bar similar to P<3>. A contact, Fig. 6, is carried by a lever M<1> and is depressed by a cam M, which may be arranged on the side of the chamber B. The guard L is actuated by a pinion L<4>, which is rotated by a rack on the chamber B, or by a rack loosely mounted on the crown of the chamber A and normally locked by a pawl. A lug on the back of the rack is actuated by lugs on the chamber B, and the locking-pawl is forced open at the required time to allow the guard to move. The 'same mechanism may actuate a guard-plate L<8> arranged in the base-ring ; or this plate may be rotated by a rack L<5>, carried by the outer chamber B and supported by an arm X<9>. The rack L<5> by means of gear-wheels L<6>, L<1> rotates the plate L<8>, and allows a contact C to pass through a tapered aperture L9. A flange B<5> carries the lock J<6>. A spring stop on one chamber may give a slight resistance to the closing of the chambers. The chambers A, B, Fig. 10, are normally kept raised by springs A<3>, B<6>, respectively, and the chamber B is formed with a pin or pins P', which engage an annular recess formed in a flange B<5>. When the chamber B has moved to the closed position, the pins P<4> come over vertical recesses P<5> in the flange B<5>, and the chambers A, B may then be depressed by hand to close hidden switches in the vertical recesses, and contacts C<14>, C<15>, C<16>, respectively, operate the contact C, and pass through apertures L9, L<11>. A pivoted guard L is moved aside automatically for the contact C<3> to touch the lamp, and a stop B<7> prevents the chamber B from being rotated too far. A tube B<4> with an extensible end B<9> protects electric wires, and a rod A<4> prevents rotation of the chamber A. In a further modification, the lamp is provided with projections which engage vertical recesses in the lamp ring N, and the projections are moved to form a bayonet-like joint into horizontal recesses in the ring, which contain hidden switches. In further forms: (1) a spring- controlled guard-plate is moved when allowed to do so by a recess in the chamber B, and a spring contact - piece C then moves through the guard-plate and base of the chamber A ; (2) a lamp screws into its base-ring and closes contacts only when secured right in. As shown in Fig. 15, the lamp is placed in a subsidiary inner chamber A<5> slightly shorter than the inside of the chamber A. The chamber A<5> is formed with pins P<4> which fit into bayonet-slots in the chamber A, the door of chamber A<5> is automatically closed during the attachment of chamber A<5>, and the pins P<4> finally close hidden switches in recesses P<6>. In further forms : (1) a chamber A shaped like a quarter of a cylinder is situated in a cylindrical chamber B, carrying a contact C<3> which passes through an aperture in chamber A ; (2) in a form similar to (1), the chamber B carries a visible push C3, and the chamber A, which is open at the top, is in the open position protected by a cover fixed to the chamber B ; (3) the guard-plate is cylindrical, and is arranged between the chambers A, B, and the push is operated from the side. The hinged door H<1> of the chamber B may be arranged, as in Fig. 24, with a squared-off portion 11, which prevents the door from being open except when the part 11 is opposite to a recess 12 in the chamber A. Semicylindrical or rectangular chambers may be used, and the parts may be arranged in different ways from those shown and described. According to the Provisional Specification, the lamp may be tightly depressed on the base-piece by a surrounding cap or frame actuated by gearing, links, and levers, &c., the arrangement being such that the circuit will not be completed if the lamp is absent.