DE1280786B - Wandering longwall mining for underground mining operations - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

E21d

German KL: 5C-23 / 0O

Number: 1280786

File number: P 12 80 786.2-24 (G 42738)

Filing date: February 3, 1965

Opening day: October 24, 1968

The invention relates to a traveling longwall mining for underground mining operations with in Extraction machine guided in the longitudinal direction of the face, with rear devices for advancing the support elements is provided against the dismantling front and a sequence control with which the reverse process the extension frame is controlled against the working joint.

The state of the art is a traveling longwall construction with a mining machine guided in the longitudinal direction of the face known, in which the control organs used to control the return process of the expansion elements are caused by the mining machine passing by to be triggered. Such a control of the expansion elements has the disadvantage that the advance the extension elements against the mining front only by the passing mining machine can be triggered. This makes the two operations, obtaining and advancing the Expansion, too closely linked, so that the disturbances in a work process are immediate and have to affect the other work process at the same time. It has been found in practice that for these reasons it is undesirable and expedient that the advance of the Expansion elements can only be triggered by the passing mining machine.

That is why control systems have been developed for mobile longwall mining in which the Advance of the individual expansion elements is controlled in another way, for example by hand or with the help of so-called sequence controls.

With these sequential controls, a control impulse is usually given by the one that has just been advanced and again set expansion element passed on to the next expansion element, this As a rule, it is only passed on when the extension element has just been moved forward and set again is advanced by the full stride length and is set again with full setting pressure. It is known, to check this by means of appropriate automatic control devices in the sequence control, for example by interposing an end valve that is actuated when the rear cylinder the expansion element has advanced the full step length and a pressure control valve, that only allows the control pulse to be passed on to the next extension element, when the full setting pressure is reached.

Both the manual control and the automatic sequential control have achieved good results in practice, which is partly the result of migrating longwall mining for underground mining
Mining operations

Applicant:

Gullick Limited, Wigan, Lancashire

(Great Britain)

Representative:

Dipl.-Ing. H. Bode, patent attorney,

4033 Hösel, Am Rennbaum 29

Named as inventor:

Archelaius Dawson Allen, Leyland, Lancashire;

Richard Ward, Worsley, Lancashire

(Great Britain)

Claimed priority:

Great Britain 7 February 1964 (5273) -

is due to the fact that the expansion elements are not only in each case when the mining machine drives past can be moved, making the expansion much easier to disruptions and irregular Ratios can be adjusted.

As a result of the separation of the two work processes, winning and advancing the expansion, it can happen at the manual control or the automatic sequence control, however, it can happen that one or more expansion elements are advanced before the mining machine in question Place in the longwall. In the case of manual control, this is particularly the case if the operator is inattentive to be feared, or if the reverse process is caused, for example, by falling rock, toughness etc. can be triggered. In the case of automatic sequencing, this is undesirable premature Advancement of individual expansion elements is to be feared especially when the control impulse, the advance the individual expansion elements triggers, the longwall can traverse faster than the mining machine.

In both cases, this can cause serious damage or malfunctions if such an improperly advanced expansion element obstructs the route of the mining

809 628/1144

3 4

machine blocked. It is therefore the task of the earth- d) to give a warning signal if an expansion is found, the known expansion with automatic element is not advanced in an unlawful manner, To develop sequential control in such a way that the expansion or when the advance of the expansion elements construction elements only after driving past the extraction behind the progress of the extraction machine machine can be advanced. 5 remains.

The subject of the invention is a migratory essentially containing the electrical equipment Longwall mining for underground mining operations with a high-current photo for each extension element Mining machine guided in the longitudinal direction, zelle, ζ. B. a cadmium sulfide photocell 10, a with reverse devices for advancing the expansion self-holding relay with a winding lla and elements against the dismantling front and a subsequent io contacts 116, one on hydraulic pressure control, with which the reverse operation of the expressive changeover switch 12 and a solenoid valve 13. construction frame is controlled against the mining shock, the holding contacts 10 a of the self-holding relay whereby this wandering longwall are connected in parallel to the photocell 10, indicates that in the control between the To increase the internal security of the circuit individual expansion elements locking members provided 15 can be parallel to the winding 11a of the self-retaining, which are arranged by the extraction machine in which the relay a diode. Passage can be unlocked. In Fig. 1 are the electrical supply lines

The expansion according to the invention is the gene with E and the hydraulic lines with H

The advantage given that no expansion element referred to advanced.

can be before the extraction machine the 20 The in F i g. 2 has expansion element shown

has passed the corresponding point in the longwall. As a result, a base plate 14 on which at 15 a link 16

it is ensured that no prematurely advanced is pivotally attached to its upper end

Expansion element carries the route of the extraction a hanging wall 17. The handlebar 16 or

machine can block. Nevertheless, the hanging wall plate 17 attached to it can remain with Expansion according to the invention, the two working 25 aid of a hydraulic pit ram 18 against

operations, winning and advancing the expansion, the hanging wall are pressed. The hydraulic one

largely independent of each other, so that the pit punch 18 is pivotable at 19 with the

Disturbances during a work process do not immediately appear on the base plate 14 of the expansion element and at 20

affect the other operation. pivotally connected to the handlebar 16. The out-of-advantage Embodiments of the longwall structure 30 component can be one or more hydraulic

according to the invention result from the sub-pit punch 18 have.

address. Two embodiments of a longwall in F i g. 2 not shown hydraulically loaded

expansion according to the invention are operated pressure switch 12 speaks in a previous

Hand outlined drawing. It shows correct hydraulic pressure within the group

Fig. 1 in connection with the hydraulic 35 benstempels 18 at.

Systems of two adjacent with a follower control- Within the base plate 14 of the expansion element-

tion of provided hiking pillars, whose photocell tes is a double-acting hydraulic

provided locking devices in simplified Dar back cylinder 21, which is pivotable at 22 on the

Position, base plate 14 is attached. The piston rod 23

F i g. Figure 2 is a side view of an extension member 40 of the advance cylinder 21 at its free end

and provided with a coupling 24, with the help of which they

F i g. 3, the hydraulic systems of two adjacent ones are attached to the conveyor 25.

barter provided with a sequence control within a strut is located along the

piers with a mechanically triggered hydraulic dismantling front arranged next to each other a considerable

rule locking device, 45 borrowed number of expansion elements.

F i g. 4 the circuit of an overcurrent warning and In the in F i g. 2 is the position shown

-Display device for the locking device according to rod 23 of the advance cylinder 21 extended,

Fig. 1 and around the face conveyor 25 against the mining front

F i g. 5 a photocell circuit to prevent nod. The mining machine 26 wins at

of the undesired triggering of the locking device 50 an operation a pack of coal that is not the

by extraneous light, corresponds to the full thickness of the seam, but rather

Fig. 6 and 7 in perspective view only about half the seam thickness. Next up

and in section light sources for the joint operation are provided by the extraction machine 26

act with the in F i g. 1 shown locking front of the hanging wall pack from the dismantling front.

direction. 55 won, so that it is necessary to

The in F i g. The arrangement shown in FIG. 1 has the plate 17 of the expansion element under the newly exposed Tasks to be fulfilled: to move the laid hanging wall forward. For this purpose, the KoI-

a) the hydraulic advance and subsequent rod 23 in the advance cylinder 21-put initiate the expansion element, followed by the face conveyor 25 as an abutment which the mining machine serves on its way 60, so that the expansion element against the mining along the dismantling front is advanced on the extension element front.

has passed, the extraction machine 26 has a light

b) ensure that the expansion element only source 27, which is on a bracket attached to it can then be advanced when the ge 28 is in place. This light source 27 exposed the extraction machine has passed, 65 photocell 10 of each expansion element on which

c) to ensure that no expansion element passes by except for the extraction machine. The exposure of the row before the thread photocell passes by means that the self-holding machine can be advanced, relay 11a, Ub is attracted and in the

drawn position by the action of the self-holding contacts 10 α remains hanging and on this Wise "reminded" that the extraction machine passed the extension element in question is.

The hydraulic equipment, by means of which the advance of each expansion element arranged in the series is triggered by the preceding expansion element, contains two piston slide valves 13 α and 13 b, which are actuated by an end stop valve 13 c, which is arranged on the advance cylinder 21 . The device is designed so that when an expansion element has been fully advanced with the aid of its advance cylinder 21 (by fully retracting the piston rod 23 into the advance cylinder 21), the piston slide valves of the next expansion element are set so that this expansion element is also advanced can.

The solenoid valves 13, which trigger the advancement of that expansion element in which they are located, get their excitation current in that the normally open contacts of the changeover switch 12 in the preceding expansion element and the normally open contacts 11a of the relay Ub in the advancing expansion element are closed. The relay contacts are in series with the contacts of the switch 12.

The device described above works as follows:

It is assumed that an extension element has just been set, ie the face conveyor has been advanced, the extension element has been tightened and the hydraulic pit ram (s) are braced against the hanging wall. Once in the hydraulic pit punches 18 of the expansion member of the full set pressure has been achieved, the hydraulically actuated change-over switch 12 switches in such a position to where it joins the magnetic switch 13 of the following expansion element on one side of the power supply and at the same time the self-maintaining relay 11a, 11b brings his own expansion element by cutting off the self-holding contacts 10 a in its rest position. Now the following expansion element can begin with the advance process, provided, however, that its latching relay 11a, Ub has picked up and is therefore in its working position in which the contacts 11b are closed. The self-holding relay 11 a, 116 then reaches its working position when the photocell 10 is illuminated by the light source 27 of the mining machine 26 passing by. As long as this has not happened, the expansion element remains in the waiting position and the advance process only begins when the extraction machine has passed the expansion element. In the normal course of the longwall mining work, the extension elements are pulled forward one after the other, shortly after the mining machine has passed, and it is not possible for several extension elements to advance at the same time.

In the design of the device described above, consideration has already been given to that the following errors could occur under certain circumstances:

a) Failure of the electrical power supply or the pressure medium supply.

b) An extension element does not reach its full setting load, for example due to incorrect work of the expansion element.

c) Unwanted triggering of the self-holding relay of an expansion element on which the mining machine Has not yet driven past, for example by exposure to light from a miner's lamp.

d) Simultaneous advancement of more than one expansion element by simultaneous excitation of the Solenoid valves of several expansion elements.

e) The advancement of the expansion elements remains behind the progress of the extraction device far behind.

f) Incorrect holding (sticking) of the hydraulic pressure operated changeover switch 12 in one of its two switch positions.

The device described above has the following safety precautions:

1. Overcurrent measuring and display devices both in the supply circuits of the self-holding Relays as well as the solenoid valves.

2. Power failure measuring and display devices at both ends of the for supplying the self-holding Relay serving looped supply line.

3. A rectifier 29 and a warning lamp 30, connected in series, the coil of the solenoid valve and bridge the associated relay contact of each expansion element.

4. A switch located in a control panel for reversing the polarity of the power supply circuit for the solenoid valves and a display device to be able to determine whether current is flowing in the reverse polarity direction.

When the errors identified above with a) and b) occur, the following happens:

The failure of the supply of hydraulic pressure medium or the failure of the power supply for the solenoid valves has the consequence that the advancing and setting of the expansion elements does not take place. The functioning of the self-holding relay is not affected. The failure of the power supply for the latching relays also prevents the expansion elements and from advancing also the activity of the self-holding relay.

If there is an interruption in the order of the advancing expansion elements, but the self-retaining relays are still working, and the extraction machine is now working on several expansion elements passes, the result is that several latching relays are energized at the same time are. The overcurrent measuring and display device on the control panel of the extension is set in such a way that that it responds when the windings of several, for example more than one, are self-retaining Relay take up current at the same time, and the overcurrent measuring and display device then triggers Warning signal off.

An overcurrent measuring and indicating device for this purpose is shown in FIG. 4 shown. The device is connected between the power supply line and as a DC amplifier with a downstream Relay built up. The circuit arrangement contains an emitter-coupled transistor amplifier 32, a relay 33, an adjustment potentiometer 34 and a series resistor 35. In parallel with the adjustment potentiometer 34 becomes the power supply

7 8

switched on, the direct current output responds to the eluted or intermittent light, as it is denoted by S ₁ components - for example, emanates from light sources that are connected to the

The potentiometer 34 is adjusted so that AC mains are connected. In the case of the transistor TR ₁ F i g. 5 circuit shown is a photo transformer, so that the current through the winding of the 5 sistor37 is used as a light-sensitive element, relay 33 in the collector circuit of the transistor and the circuit is designed so that its TR _{2 is} negligibly small. If, however, an alternating current is available at the output, the current through the series resistor 35 increases when the phototransistor exceeds an alternating current-adjusted value which is exposed by the setting-modulated light source. The Tranlung of the potentiometer 34 is predetermined, the io sistor 38 is conductive by means of capacitors to the photo-transistor TR ₂ and energizes the relay 33. Coupled with transistor 37 and receives no signal, the contacts of the relay 33 are then used when the Phototransistor 37 is exposed to the desired display or warning devices with unmodulated light, for example with the light of a switched on, which, however, receives attention to the fault that has occurred on DC-operated miner's lamp. 15 the transistor 38 at its base via the between

The potentiometer 34 can be calibrated so that the base and emitter lying rectifier 39 it in advance on a certain number of current- DC signal when on the phototransistor Recording self-holding relay or magnetically modulated light can be set by a suitable modulation valve, the required frequency acts. If so, it will are to such a high current flow through the An 20 in the collector circuit of the transistor 38 lying Pointing device to generate that the relay 33 on-latching relays 11a, 11 & excites and picks up. pulls and triggers the warning devices. As a light source 27 on the boom 28 of the threaded

The self-holding relays are made from a power supply machine 26, a fluorescent lamp 40 supply line fed, which, from the control stand (see Figs. 6 and 7), whose luminous flux is very starting, is modulated by all expansion elements of a 25 shaped in the mains alternating current rhythm. associated group through and back Such a lamp can be arranged so that is looped to the control point. At both ends they have a narrow, perpendicular (right-angled to the strut) Loop are tension measuring devices in the longitudinal direction) emits a strip of light so that closed, which sends a signal in the event of a power failure - even larger differences in height between the loops and thus no interruptions in the loop 30 extraction machine and the expansion element and indicate the failure of the power supply. show adverse consequences. The light emission will

With the help of this device, the under a) are appropriately limited to a narrow band, so that described error discovered immediately. it is ensured that only the photocell of the

The overcurrent display device (FIG. 4) in the supply line opposite the mining machine the latching relay shows 35 the expansion element receives light. Can do this In addition, the errors b) and e), since in Auf- it, as shown in Fi g. 6 and 7 is shown to occur of each of these two defects several moderate ones, before the elongated fluorescence self-sustaining one Pull the relay at the same time, in the case of lamp 40 a semi-cylindrical lens 41 and behind of the error b) in that the consequence of the front of the fluorescent lamp has a trough-shaped back is interrupted, and in the case of the faulty reflector 42 to be arranged.

lers e) by the fact that the advance of the individual Another possibility, the undesirable and

Expansion elements takes place so slowly that this results in accidental actuation of the expansion by someone else several self-holding relays are energized at the same time to prevent light sources such as miner's lamps. says that photocells are used, their

The error c) is caused by a certain operating sensitivity to a certain spectral mode prevents: area is limited, for example photocells that

Immediately before the extraction machine sensitizes to violet and ultraviolet light one end of the strut begins to work, will are. In this case, the light source 27 could be on the power supply line of the holding relay short- the extraction machine 26 a fluorescent lamp switched off early. Due to the short-term switch-off, the transmitted spectrum can be used th, all self-holding relays drop out and, since a high violet and ultraviolet component do not separate People who have light sources in front of the stops. If necessary, you can also choose between the If the mining machine is in the longwall, the un-light source and the photocell filter used is intended for advertising Triggering (tightening) a self-sustaining one that only emits violet and ultraviolet light the relay is not possible. Let another fuse through. Because the usual battery-powered grusteht in the fact that the overcurrent display, if you benlampen in its spectrum only a very properly set, it immediately indicates when a low percentage of purple and even less larger number of self-holding relays have ultraviolet light current, it is practically absorbing than this in normal operation of the closed, with such a light source one on Case should be. 60 violet and ultraviolet light sensitized photo

In order to successfully expose the expansion completely insensitive to uncell.

intended actuation, for example caused by the consequences of the error d) are thereby depressed one of the photocells, through a pit, prevents it from being in the supply circuit of the magnetic lamp or by some other coincidentally in their valves an overcurrent measuring and display device similar proximity located light source could take place, 65 can be borrowed F i g. 4 is arranged, which is set so that the circuit arrangement according to FIG. 5 uses the warning and display devices associated with it. For this purpose, a capacitor-coupled line will come into operation as soon as more than one Photocell amplifier used, which is only operated on the modu solenoid valve.

The error f), namely that one of the changeover switches 12 gets stuck in the "off" position, is noticeable in that when it occurs, the advancement of the extension elements is interrupted, but not the attraction of further latching relays, which is caused by the overcurrent indicator the latching relay is visible. In order to determine whether one of the changeover switches 12 has got stuck in the "on" position, the polarity of the supply voltage for the solenoid valves is reversed before the extraction machine begins a cycle. The above-mentioned rectifier 29 and warning lamps 30 connected in series, which each bridge the coils of the solenoid valves and their associated relay contacts, are, as far as the rectifier is concerned, polarized so that the rectifier does not let any current through during normal operation. If, however, the polarity of the supply voltage for the solenoid valves is reversed, the rectifier whose changeover switch 12 has got stuck in the switch position "on" ao is allowed to pass, and the associated warning lamp lights up. At the control panel, the appropriately set overcurrent warning and display device can be used to determine whether any of the changeover switches 12 should be in the "on" position inadmissibly before the start of the advancement process of the group of expansion elements and, if this is the case, the faulty changeover switch can be quickly located using the warning lamps 30; it is located in the extension element that is followed by the extension element whose warning light is on.

Each of the expansion elements is also provided with a manually operated valve 36, with the help of which all operations of the expansion element can be controlled by hand, if necessary is.

The in F i g. The device shown in FIG. 3 corresponds in some essential parts to FIG. 1 and, as far as it is possible that the same reference numerals have been used to designate the same parts. Each the expansion elements is assigned a mechanically releasable valve whose release lever 31 in the Passing the extraction machine is operated on the expansion element. This valve is hydraulic self-holding valve formed. With the in F i g. 3 is the advancement of each expansion element, albeit the advance process from the preceding expansion element has already been initiated, prevented until the mining machine drives past and the actuation of the actuating lever 31 releases the associated valve, the advance process.

Claims (17)

Claims: 55 1. Migrating longwall mining for underground mining operations with longitudinally guided Extraction machine, with rear devices for advancing the support elements against the dismantling front and a sequence control, with which the reverse process of the expansion frame is controlled against the mining shock, characterized in that in the control between the individual expansion elements (16) locking members (10,11,12) are provided by the Extraction machine (26) are unlocked when they pass. 2. longwall mining according to claim 1, characterized in that the locking members on the expansion elements arranged photocells (10) and on the extraction machine (26) a light source (27) is arranged, which when driving past the extraction machine (26) the photocells (10) arranged on the extension elements exposed. 3. longwall construction according to claim 1, characterized in that in the actuation of the advancing cylinder A valve (31) is arranged (21) of the hydraulic fluid line serving the rear device is caused by mechanical contact with the passing mining machine (26) can be triggered. 4. Longwall construction according to claim 2, characterized in that the expansion elements contain solenoid valves (13) for the advance cylinder, and a changeover switch (12) which is arranged in the actuating circuit of the solenoid valve (13) and is actuated by setting the preceding expansion element, as well a self-maintaining relay (lla, 11b) in the actuation circuit of the solenoid valve (13), wherein the excitation circuit of the self-holding relays (11 a, II b), a photocell (10) is arranged, upon exposure by the light source (27) of the passing extraction machine (26) energizes the self-holding relay (11 a, 11 b) so that the expansion element can only be advanced after the preceding expansion element has been set and after the mining machine (26) has passed. 5. longwall construction according to claim 4, characterized in that the changeover switch (12) through hydraulic pressure actuated switch, which is set to a predetermined response pressure in the hydraulic System (18) of the expansion element is set and for switching the actuating circuit of the solenoid valve (13) of the following Expansion element is used. 6. face construction according to claim 4 and / or 5, characterized in that an overcurrent display device is arranged in the excitation power supply line of the self-holding relay (11a, lib). 7. longwall mining according to claims 4 to 6, characterized in that in the actuating power supply line the solenoid valves (13) an overcurrent indicator is arranged. 8. Longwall construction according to claims 4 to 7, characterized in that the excitation power supply line of the self-holding relay (11a, 11b) is looped through all the expansion elements of a group that belongs together, with voltage failure display devices being arranged at both ends of the loop. 9. longwall construction according to claims 4 to 8, characterized in that parallel to the magnet coil of each solenoid valve (13) a warning lamp and a rectifier connected in series so that the warning lamp lights up when a switch (12) gets stuck in the on position. 10. longwall construction according to claims 4 to 9, characterized in that the windings (lla) the self-holding relay (Ha, 116) through Diodes are bridged. 809 628/1144 11. longwall construction according to claims 2, 4 to 10, characterized in that as photocells (10) High-current photocells, preferably cadmium sulfide cells, can be used. 12. Longwall construction according to claims 2, 4 to 10, characterized in that as photocells (10) Phototransistors are used. 13. Longwall construction according to claims 2, 4 to 12, characterized in that the photocell circuits modulated light only, e.g. B. with the frequency of the AC power modulated light respond. 14. longwall mining according to claim 13, characterized in that the mining machine (26) attached light source (27) is a fluorescent lamp (40). 15. Longwall construction according to claim 14, characterized in that the fluorescent lamp (40) elongated and with a trough-shaped reflector (42) and an elongated semi-ao cylindrical lens (41) is provided. 16. Longwall construction according to claims 11 and / or 12, characterized in that the photocells (10) are sensitized to a spectral range that is used for lighting purposes electric incandescent lamps, in particular miner's lamps, are not emitted or only emitted to a limited extent will. 17. Longwall construction according to claim 16, characterized in that the mining machine (26) attached light source (27) preferably emits light of that spectral range, to which the photocell (10) is sensitized. Considered publications: German Auslegeschrift No. 1069 548,
629; French Patent No. 1271386; British Patent No. 823128; "Bergbautechnik", Vol. 6, Issue 4, April 1956; "Electric control and regulation", by S. Jahn, R. Pflaum Verlag, Munich. For this purpose 2 sheets of drawings 809 628/1144 10.68 © Bundesdruckerei Berlin