Hiding device (carrier)

A hiding device , also known as a changing device, is a mechanical device which, in the case of double drum winding machines and double bobbin winding machines , enables the connection between the cable carrier and the drive shaft to be optionally disconnected or connected. Thereby, it is in the well production possible, a 2-basket operating at different soles perform. Furthermore, rope stretching can be compensated with the hiding device.

Basics

In the case of shaft hoisting systems, it is generally not possible to use two baskets to convey different soles. Particularly in the case of traction sheave conveyance, the conveyance of several soles in two-basket operation is impossible due to the constant rope length. In the case of double drum winding machines and double bobbin winding machines, this property can be compensated for by means of design measures. For this purpose, a special coupling must be installed between the two cable cages or between one of the drums and the drive shaft. As a result, one of the drums is now fixed and the other is loosely connected to the drive shaft. The drum firmly connected to the drive shaft is called the fixed drum , the separable drum is called the loose drum . There are machines with one lottery wheel and one fixed drum and machines with two lottery drums. Appropriately , they are called fixed reel and loose reel in reel conveyor systems . By mutually rotating the drums, the hoisting rope can be wound onto one of the drums in hiding mode. As a result, the route of the conveyor system is now changed according to the shortening of the rope. In the case of hiding, the lottery wheel must be blocked during work. In the simplest case, this is done with a specially shaped holding rod. In today's machines, the lottery wheel is equipped with an additional brake that blocks the lottery wheel during work.

Coupling devices

To make the connection between the loose drum and the fixed drum separable, there are different types of coupling: pin, tooth and friction clutches. The respective clutch can be operated manually or mechanically, depending on the design.

Pin coupling

With the pin coupling, a split hub is attached to the drum and to the drive shaft, in the connecting flange of which there are holes at certain intervals. Bolts are inserted through these holes to connect the two halves. In order to be able to loosen the bolts, the lottery wheel must first be fixed. This is done by means of a special support rod that is movably connected to the machine frame at the lower end. As soon as the drum is fixed by means of the holding rod, the socket pins can be pulled out and reinserted at a desired point. So that the pin coupling can be hidden more finely, the holes are divided in the hub flanges by means of a special arrangement of the holes. In this hole division , known as a vernier division, nine holes are drilled in one hub flange and ten holes in the other hub flange. The start and end holes are at the same flange point. With this arrangement of the holes it is now possible that a bolt can be plugged onto 1/12 of the flange circumference. A disadvantage of the pin coupling is that the pins are heavily stressed due to the power transmission. In order to reduce the shearing effect on the individual bolts, as many bolts as possible must be inserted through the two flanges. Despite this measure, it can happen that the forces acting are distributed unevenly on the bolts. This will bend some of the bolts, making them difficult to change.

Tooth coupling

In the case of the tooth coupling, the two hub halves are also connected in a form-fitting manner through toothing. For this purpose, one hub half is designed as a gear. Due to the close succession of teeth, a finer degree of hiding is possible. This is particularly advantageous when hiding the hoisting rope, since the hoisting rope does not have to be hidden on the intermediate harness . The gear wheel (shaft wheel) is provided with external teeth. As a counterpart for the gear, a corresponding counterpart is mounted on the shaft of the loose drum. This counterpart (drum wheel) is provided with internal teeth. Both parts can be equipped with tooth segments or be fully toothed. Gear and counterpart are designed so that they fit into one another without any problems. This enables the coupling process to be carried out without difficulty. To engage and disengage, the counterpart is moved in the radial direction by means of a handwheel. The teeth are made sufficiently long so that the individual teeth are not overstrained by shear forces. In addition, several teeth are always engaged at the same time so that the forces are evenly distributed.

Friction clutch

With the friction clutch, the two clutch halves are connected in a force-locking manner through friction. A coupling ring is attached to the fixed drum. There are two clutch jaws on the lottery wheel. For coupling, the coupling jaws are pressed against the coupling ring via screws and gear drives. This is done via a screw spindle that is shifted in the drum and moves two spur gears. The drive unit is moved by a handwheel during the coupling process. The force is transferred from the handwheel to the drive unit via a lever. In order to achieve an even contact pressure, there are springs in the pull rod between the clutch shoes and the clutch ring . The advantage of the friction clutch is that it is easily accessible from the outside.

Modifications

In addition to the manual drives for the clutches, there are also mechanical drives. This makes the relocating process safer and easier. There are tooth clutches in which the coupling process is carried out by an electric motor. In these toothed clutches, the clutch segment on the loose drum is moved back and forth by means of a three-phase motor . The motor is mounted in the lottery wheel and moves the coupling segment via bevel gears and a screw drive. So that the motor can move the coupling segment back and forth, it is switched via a control unit in such a way that it turns either clockwise or anti-clockwise while moving the coupling segment forwards or backwards. With this coupling , the haulage operator can disengage, shift and engage from his driver's cab without additional help. The gear wheel and the coupling segment can only be pushed into one another if the teeth and the gaps are exactly in front of one another. So that this is also visible to the machinist from the outside, appropriate symbols are attached to the lottery wheel and to the fixed drum. There are also tooth clutches in which the coupling process takes place by means of compressed air cylinders. With these quick hiding devices, the cylinder is actuated via compressed air control. The hand lever of the hidden brake is locked via the compressed air control so that the clutch cannot be operated when the brake is open. Machine-operated clutches are of great advantage in particular in shaft hoisting systems, in which different floors are regularly conveyed and therefore have to be hidden several times a day.

The hiding place

In order to be able to carry out the hiding process, the loose drum must be uncoupled. If both baskets are to be conveyed from a higher level, the conveyor frame is first moved to the upper level. The conveyor cage is then fixed there by applying the brake to the lottery wheel. Then the lottery wheel is decoupled from the hub. Now the conveyor frame on the fixed drum is moved to the hanging bench . As soon as the second basket is on the hanging bench, the lottery wheel is coupled again with the drive shaft. The shaft hoisting system is now ready for conveyance to the upper level. If a lower level is to be used again, the basket on the lottery wheel is first moved to the hanging bench. The coupling process already described is then carried out, then the second basket is moved to the lower sole and then the loose drum and the drive shaft are coupled together again. When hiding a hauling rope that is too long, the procedure is adequate. The basket of the lottery wheel is first moved to the hanging bench, where the lottery wheel is braked and uncoupled. Then the counter-cage is moved on the relevant sole until it is flush again. Then the clutch is engaged again.

Dangers in hiding

For safety reasons, hiding is only allowed if no one is on the conveyor. On June 15, 1921, there was a serious accident while hiding because the band brake did not hold the lottery wheel. All twelve miners on the basket were killed when the basket in Shaft I of the Florentin Kästner hard coal works in Reinsdorf near Zwickau came off the hanging bench and sped 557 m into the shaft sump . The safety gear, which should have braked a hoist cage that had lost its rope, did not activate because the rope had not broken.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m Fritz Schmidt: The basics of the conveyor machine system . First part, second increased and improved edition, Springer-Verlag Berlin Heidelberg GmbH, Berlin Heidelberg 1923, pp. 49, 144-146, 149, 155-160.
↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k Hans Bansen (Ed.): The mining machines . Third Volume, The Shaft Carriers. Published by Julius Springer, Berlin 1913, pp. 79–80, 103–104, 109–115.
↑ ^a ^b ^c ^d ^e ^f ^g Horst Roschlau, Wolfram Heintze: Bergmaschinentechnik. VEB German publishing house for basic industry, Leipzig 1977, pp. 260-261.
↑ ^a ^b W. Sindern, St. Borowski: Safety considerations on shaft hoisting systems for access to a future deep geological repository . Work report NAB 14-75, National Cooperative for the Storage of Radioactive Waste (Ed.), Wettingen 2014, p. 38.
↑ ^a ^b ^c ^d ^e ^f ^g Carl Hellmut Fritzsche: Textbook of mining science. First volume, 9th edition. Springer Verlag, Berlin / Göttingen / Heidelberg 1955, pp. 512-513.
↑ ^a ^b ^c Walter Schröder: Drum winder with a driven main shaft . Patent specification from Olko Maschinenfabrik GmbH dated April 10, 2014, publication number WO2014053299 A1.
↑ ^a ^b H. Hoffmann, C. Hoffmann: Textbook of mining machines (power and work machines) . 3rd edition, Springer Verlag OHG, Berlin 1941, pp. 172-174.
↑ ^a ^b Stephan Sonneborn hiding device . Patent specification of Siemag Tecberg GmbH dated July 24, 2014, publication number WO 2014111515 A1.
↑ Jacob Berns, Stephan Sonneborn, Klaus Hofmann: Hiding device for conveyors . Patent specification from Siemag Tecberg GmbH dated July 24, 2014, publication number DE 102013005562 A1.
↑ Author collective: The coal mining in the Zwickau area . Ed .: Steinkohlenbergbauverein Zwickau eV Förster & Borries, Zwickau 2000, ISBN 3-00-006207-6 , p. 88 .
^ Sächsisches Bergamt Freiberg (Sa.) (Hrsg.): Yearbook for the mining and metallurgical industry in Saxony. Born in 1922. Statistics from 1921. 96th year. Craz & Gerlach, Freiberg 1922, C. Special overview of the fatal accidents that occurred in mining in 1921., P. B65 .

[Quelle_1-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m Fritz Schmidt: The basics of the conveyor machine system . First part, second increased and improved edition, Springer-Verlag Berlin Heidelberg GmbH, Berlin Heidelberg 1923, pp. 49, 144-146, 149, 155-160.

[Quelle_5-2] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k Hans Bansen (Ed.): The mining machines . Third Volume, The Shaft Carriers. Published by Julius Springer, Berlin 1913, pp. 79–80, 103–104, 109–115.

[Quelle_2-3] ↑ ^a ^b ^c ^d ^e ^f ^g Horst Roschlau, Wolfram Heintze: Bergmaschinentechnik. VEB German publishing house for basic industry, Leipzig 1977, pp. 260-261.

[Quelle_3-4] W. Sindern, St. Borowski: Safety considerations on shaft hoisting systems for access to a future deep geological repository . Work report NAB 14-75, National Cooperative for the Storage of Radioactive Waste (Ed.), Wettingen 2014, p. 38.

[Quelle_4-5] ↑ ^a ^b ^c ^d ^e ^f ^g Carl Hellmut Fritzsche: Textbook of mining science. First volume, 9th edition. Springer Verlag, Berlin / Göttingen / Heidelberg 1955, pp. 512-513.

[Quelle_7-6] Walter Schröder: Drum winder with a driven main shaft . Patent specification from Olko Maschinenfabrik GmbH dated April 10, 2014, publication number WO2014053299 A1.

[Quelle_6-7] H. Hoffmann, C. Hoffmann: Textbook of mining machines (power and work machines) . 3rd edition, Springer Verlag OHG, Berlin 1941, pp. 172-174.

[Quelle_9-8] Stephan Sonneborn hiding device . Patent specification of Siemag Tecberg GmbH dated July 24, 2014, publication number WO 2014111515 A1.

[Quelle_8-9] Jacob Berns, Stephan Sonneborn, Klaus Hofmann: Hiding device for conveyors . Patent specification from Siemag Tecberg GmbH dated July 24, 2014, publication number DE 102013005562 A1.

[Quelle_10-10] Author collective: The coal mining in the Zwickau area . Ed .: Steinkohlenbergbauverein Zwickau eV Förster & Borries, Zwickau 2000, ISBN 3-00-006207-6 , p. 88 .

[Quelle_11-11] Sächsisches Bergamt Freiberg (Sa.) (Hrsg.): Yearbook for the mining and metallurgical industry in Saxony. Born in 1922. Statistics from 1921. 96th year. Craz & Gerlach, Freiberg 1922, C. Special overview of the fatal accidents that occurred in mining in 1921., P. B65 .