Patent GB-668102-A (GB)
Title: Portable electric battery
IPC: H01M50/147
Filed: 1950-01-04
Abstract: 668,102. Accumulators. TRIGGS, W. W. (Edison, Inc., T. A.). Jan. 4, 1950, No. 192/50. Class 53. [Also in Group XXV]  An accumulator which may be of the nickel iron type and particularly for use with lamps in mines is provided with a pair of terminals for the output to the lamp and a second pair for charging. The terminals are mounted on the lid of the casing and are enclosed in a second hinged cover which when closed connects the battery to the output terminals. The cover is provided with a magnetic lock and when this is released by a magnet a spring causes the cover to open sufficiently to expose the charging terminals, the circuit to the output terminals being simultaneously interrupted. The partial opening of the cover is limited by a catch which can be released manually to enable the cover to be fully opened if access is required to all the terminals, filling openings, gas vents &c. As shown in Fig. 7, the casing 10 of the accumulator is divided by a partition 11 into two compartments 12, 13 in each of which are two cells 14, 15, the containers of the cells 14 constituting negative terminals and the containers of the cells 15 being positive terminals. The containers of the two cells in each compartment are joined together so that the cells are in series, and the two cells in one compartment are connected in series with those in the other compartment by means of a strap 19. One terminal 22 of the battery is connected by a strap 20 to the terminal post 14a of one cell, another terminal 22b being connected through a conductor 28 to a strap 21 connected to the post 15a of a cell in the second compartment. The terminals 22, 22b are provided with upstanding blades 29, 30, Fig. 2, which constitute the charging terminals of the battery. A separate pair of output terminals 23, 23a are connected to the strap 21 and a conductor 31 leading to a terminal 22a which can be connected to the terminal 22 through a switch, the fixed contacts of which are formed by an arm 29a on the blade 29 and a contact 49 secured to the terminal 22a as shown in Fig. 3. The casing 10 is provided with a hinged cover 60 which carries a U-shaped spring 85 which when the cover is closed bridges the contacts 29a, 49, thus completing the circuit to the output terminals and cable 32. The spring 85 also serves as a catch by engagement with a fixed lug 84 to prevent the cover from opening beyond a point sufficient to expose the charging terminals 29, 30. The spring and lug can be disengaged by a screwdriver or other tool when it is desired to open the cover fully. The cover is biased to the open position by a spring 62 and encloses the terminals, gas vents and other fittings on an inner lid 33 of the battery casing. When the cover 60 is closed it is automatically looked by a magnetic look comprising two soft iron posts 72  carried by the cover and supporting a non- magnetic plate 73 having openings 74 for receiving iron pawls 64, Fig. 8. These pawls are pivoted at 66 to a casing 65 and are urged together by springs 67. The casing 65 is housed in a recess 68 in a wall 44 projecting upwardly from the lid 33. When the cover 60 is closed the centre part of the plate 73 forces the pawls apart and they then snap into the openings 74. The pawls are released by the application of a horseshoe magnet to the cover 60. The inner lid 33 is held in place by two bands 38, the upper turned-in portions 38b of which engage the lid, shoulders 38a on the bands engaging corresponding shoulders on the case. The ends of the bands are turned inwardly to form hooks 38c which project into recesses 37 formed in the sides of the case. The hooks 38c diverge upwardly as shown in Fig. 2, and are engaged by diverging hooks 39a formed on clamps 39 situated in the recesses 37 so that the ends of the bands are drawn tightly together. Ears 39b on the clamps are bent across the adjacent edges of the bands to hold them in place. The case is provided with brackets 41 to receive belt straps. Each cell of the battery is provided with a filling opening 18 in which is fitted a gas vent, Fig. 6, having two valve-controlled exits 95, 96, one of which opens at a lower pressure than the other. Each vent comprises a tube 91 having side openings 95, 96 situated. on opposite sides of a diaphragm having a central opening 99 which can be closed by a valve 102 when pressure is applied to a plunger 101. The openings 95, 96 are normally, closed by a rubber sleeve 97, the thickness of which is less where it covers the opening 95 than where it covers the opening 96. In the position of the parts shown in Fig. 6, gas has access to both openings 95, 96 and the thinner rubber surrounding the opening 95 allows the gas to escape, the opening 96 remaining closed. When the plunger 101 is pressed down to close the valve 102 the gas is cut off from the opening 95 and the pressure builds up till it causes the gas to escape through the opening 96. The plunger 101 is actuated by the cover 60 which when closed presses the plunger down to close the valve 102. When the cover is opened for charging purposes the plunger rises and gas can escape at low pressure through the opening 95. Specification 660,083 is referred to.