The Stauss keeps are made in various sizes by the Humboldt Engineering Co., Kalk, near Cologne. The casting a carries the rocking-shaft 7, the hand-lever h and lever k, both keyed on, the shaft d with the two hanging links ee fastened on and the connect ing pin b. On the latter the one-armed keep turns freely, being also supported on the inclined surface z of the bed-plate a; further, b carries the link f, which forms a toggle-joint with the lever k by means of the pin i. The arrangement works as follows: If the cage is to be held and prevented from going down the pit, it is lowered on to the keeps c; these are supported by the surfaces x and the pin b, the latter being prevented from moving vertically or horizontally. It is prevented from moving vertically by the hanging links e, which press upwards against the shaft d, and horizontally by the toggle f, which thrusts against the pin i of the lever k, and through the latter against the rocking-shaft 7. The whole arrangement is thus locked and any movement prevented, as the weight of the hand-lever h presses the lever k downwards upon the block m, which is fixed to the bed-plate a, and prevents any further downward movement. A Fig. 56. When his thrown over into the dotted position shown in Fig. 52, through an arc of 60°, i comes into position i' and b to b', thus drawing the keeps c away from under the cage and downwards, so that the cage is free to descend. Fig. 55 shows the relative positions of the different parts when the keeps are drawn back. When the cage has again been lifted to the pithead, h is pushed over into its first position, this action carrying the keeps forward and the cage can again be lowered on to them. Owing to the keeps c being free to turn. round the pin b, the cage cannot catch fast in them, if they should be pushed out too soon. No injury can result from such action, because the cage would then only lift the keeps up into the dotted position in Fig. 52, and after it had passed above them they would fall back again into their proper position by gravity. The friction which takes place between the surfaces x and y and in the joints when the keeps are withdrawn is easily overcome by the hand-lever, as the weight of the cage itself helps and endeavours to push the keeps backwards down the incline of 9° marked x. Further, as soon as the hanging links e have left the vertical position and b is turning round d as centre, the weight of the cage acting on b through c helps the movement of rotation and the force acting on i. The further the keeps recede, the greater this force becomes, until it may finally cause a sudden release of the keeps unless the angle of the incline x is suitable for gradual release, which is obtained when a is inclined at an angle of 9o. The use of these keeps has many advantages as compared with other makes, such as a considerable saving of time and of steam, and less wear and tear on the ropes and machinery, owing to the lifting of the cage to release the keeps being unnecessary. This saving of time amounts to from 3 to 6 seconds, according to the skill of the engine-man, for each lift, with single-deck cages; and for cages with several decks the saving is more in proportion. The CAGE is a receptacle for the tubs traversing the pit either empty or full. It is also the usual means of transport for the workmen and all others between the surface and the different loading stages in the shaft. The pit timber, workmen's tools, horse food, and water, and frequently the horses themselves, are lowered by means of the cage. When men are riding in one cage no loaded or empty tubs are placed in the other, or in an under or over deck of that holding them. If men are not in both cages one is allowed to run empty. The cage is usually made of wrought iron but sometimes of steel. As to its form, it is of course governed by the shape of the division of the shaft it has to run in, and it may be single or double decked, or have more decks than two if desirable. Again each deck may have one or more tubs placed in it as may be desired and arranged. Each deck floor is laid with rails to allow of the tubs being pushed in whilst the loaded ones are pulled out on opposite sides. There are various modes of keeping the tub secure in the cage during its ascent or descent. One of these is by having "false bottoms" in the cage, which is an arrangement whereby the floor of that part of the deck on which the tubs are placed falls or sinks an inch or two below the other and outer portions of the deck, but when the cage rests on the keeps all the deck floor is on one level, allowing the tubs to be changed. Another mode of securing tubs in the cage is a bar running through the cage, and at either end is placed a short lever which turns down or up on being pushed; when down it covers the ends of the tubs and prevents their moving, when up it allows them to be changed. The best form of catch is that which grips the axles on the tub being pushed in, without the necessity for the attendant to have to put his foot on the cage to work the catch. Sometimes a catch in the floor secures the tubs in place. The slides of the cage fit loosely to three sides of the wooden conductors, and are slightly bellmouthed. They are applied at the upper and lower bars of the framing. A two-decked cage would have 3 such slides on either side of it, in the usual arrangement adopted. The top of the cage is provided with an iron bonnet or cover for the protection of persons whilst descending or ascending. The cage is suspended from the rope by four short chains called "bridle" or "bull" chains, one being at each of the upper corners, and in the case of heavy cages from the middle of the longer sides as well, so that in the latter case there would be six bridle chains. Fig. 58 shows a double-decked cage, and Fig. 59 a treble-decked cage, as made by Messrs. Thornewill & Warham, Engineers, Burton-onTrent. The former is steel throughout, the deck frames being angle steel, the uprights of channel steel, and the bracings of flat steel. The deck frames have cross-bearers of angle steel, with "knee" ends riveted to the frames. The floor of each deck consists of perforated steel sheets. The cage-hangers are of forged steel and sufficiently large to form a gusset to receive the uprights, cross-bracing, and top frame; they have horns forged on them to preover when the chains are slack. vent the D link on bull chains from falling The treble-decked cage is of similar construction, the uprights being of angle instead of channel steel. The tub-catches are plain bars with bent ends, working in suitable chocks fixed to the uprights. The roof of each cage is provided with doors, so that long pit wood and other articles may be carried on the upper deck. All rivet holes are drilled and rivets where possible put in by machine. The cages are provided with guide-cheeks for square, or loops for wire rope conductors, and each deck is fitted with rails. The finished weight of the double-decked cage is 2 tons, 3 cwts., 2 qrs., without the bull-chains. They are in daily use at the Walsall Wood Colliery, Cannock Chase, where each cage lifts 8 tubs, holding 48 cwts. of coal per lift from a depth of 550 yards. The treble-decked cage weighs 2 tons, 14 cwts., 2 qrs., without the bull-chains, and is in use at the Hamstead Colliery, near Birmingham, where each cage lifts 6 tubs, holding 84 cwt. of coal per lift from a depth of 620 yards. All cages should be provided with guards to be fixed to, or removed from the top of cages at will, so as to protect workmen who have to stand on the cage roofs or covers during the time they are examining or repairing the shaft, and where the cover is of a sloping or curved form, a horizontal floor should be attachable over it to enable the workmen to move about and handle their tools. Sometimes cages have an attachment for arresting their descent in the shaft in the case of a broken rope, and are then called "safety cages." A great number of these safety appliances are before the public, but they do not seem to come into general favour. They all consist of a contrivance for gripping the guides when the strain of suspension is removed. The uncertainty, however, of their acting when the necessity arises-it may be years after being put in-seems to preclude their adoption as a means of safety. Probably the feeling is that, as something must be relied upon, and as the complication and multiplication of appliances, the greater the liability for something to go wrong, it is preferable to rely on good ropes, properly looked after, and worked with a due regard to their margin of safety. Broadbent Patent Safety Cage.-Fig. 60 shows a side elevation of the apparatus, and Fig. 61 a plan of the eccentrics and guides of Broadbent's patent safety cage. AA are the guides; B the suspending chains; CC levers |