WO2004050515A1 - Device such as a conveyor belt or a chain conveyor for transporting bulk items - Google Patents

Abstract

The invention relates to a device such as a conveyor belt or a chain conveyor for transporting bulk items, whereby it is possible to reduce the speed of said device in a secure, controlled manner in the event of a fault. According to the invention, said device is provided with a means of conveyance (2) such as a band, belt or chain; drive devices (3,4,5,6) which are arranged along the path of conveyance covered by the means of conveyance (2); braking devices (11,12, 13,14) which are associated with the drive devices (3,4,5,6) and which reduce the speed of the means of conveyance (2) resulting in the automatic braking of said means of conveyance in the case of a fault; and a control device (15, 16, 17, 18) which is connected to a central power supply (33) and which controls the braking process carried out by the respective braking device (11, 12, 13, 14) when braking occurs with respect to the means of conveyance (2) and which is provided with a power storage mechanism (36) which, if the central power supply brakes down, supplies it with at least the amount of power required for controlling at least one braking process of the braking device (11, 12, 13, 14) associated therewith.

Description

 Device for conveying loose goods, such as belt or

chain conveyors

The invention relates to a device for conveying loose goods, such as belt or chain conveyors. Such devices are used, for example, underground or above ground to transport lumpy goods such as coal, stone or ore over long transport routes. Especially when working underground, there is the problem on the one hand that sections of the route have to be covered with large inclines or descents. On the other hand, increasingly stringent requirements are placed on the safety of the operation of such conveyors in the mining sector. This concerns both the safety with which the respective goods are conveyed and the avoidance of hazards to the environment in which the conveyor is operated.

The safety requirements to be met by equipment of the type in question are described, for example, in "DIRECTIVE 94/9 / EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of March 23, 1994 on the approximation of the laws of the Member States relating to devices and protective systems for their intended use in potentially explosive atmospheres". summarized, with which the basics of the so-called "ATEX standard" have been established.

In order to be able to cope with the respective transport task, conveying devices of the type in question are Drives arranged at a distance from one another along the conveying path. As a rule, each of the drives is assigned its own braking device. These braking devices are usually set up so that they can automatically carry out braking in an emergency. For this purpose, a device known from DE 198 37 315 Cl has, for example, a spring accumulator which can be preloaded pneumatically. The ^'compressed air keeps the brake during normal conveying operation opened. If braking is to be carried out, the spring accumulator is relieved of the compressed air and the braking force required for braking is released by the spring of the spring accumulator. To monitor the correct functioning and the state of wear, the known brake is equipped with a measuring device which continuously monitors the relative position of the housing parts of the brake coupled to the brake elements. ^

In the case of a braking device designed in this way, it is ensured that the force required to carry out the braking is reliably available even if the compressed air supply fails. This ensures that the conveyor is braked in time in the event of a malfunction. At the same time, it is possible with such brakes to carry out the braking in a controlled manner during normal operation. In this way, the loads occurring during braking of the conveying means used to convey the transported goods can be minimized, with the result that the service life of the conveying means, which is typically a belt, a belt or a chain acts, and the facilities required to drive it is extended.

Such an optimized controlled braking process increases the usability and availability of the means of transport significantly. However, the known devices are not able to perform an equally controlled braking in the event of an emergency braking which becomes necessary due to a power failure. Since a high level of safety must be guaranteed with such braking, which requires correspondingly high braking forces, these uncontrolled braking operations put considerable strain on the conveying means and the devices driving it. The safety requirements to be met by belt conveyors are specified in detail in the belt conveyor guidelines of the State Mining Office from October 29, 1980 - 16.16-1-30, in particular sections 2.4.2, 2.6 and 2.9.

The object of the invention was to provide, with simple means, a device of the type explained above, with which safe, controlled braking can also be carried out in the event of a fault.

This object is achieved according to the invention by means for conveying loose goods, such as belt or chain conveyors, which are associated with the conveying devices with a conveying means, such as a belt, belt or chain, with drive devices which are arranged along the conveying path covered by the conveying means Braking devices for braking the conveyor, which automatically brake the conveyor in the event of a fault, and with a control device connected to a central energy supply is provided, which regulates the carried out by the respective braking device braking operation at each stop of the conveyor and is equipped with an energy store, which it supplies in case of failure of the central power supply at least to the power, ^'the required for the control of at least one braking operation of its associated braking device is.

A device according to the invention is distinguished from the prior art in that the control device provided for controlling the braking process is equipped with an energy store. If the central energy supply fails, this energy store provides an amount of energy which is sufficient for controlling at least one braking operation. This ensures that even in the event of a malfunction, safe and material-saving braking can be carried out in a controlled manner. No complex measures are required. Instead, an electrical accumulator of sufficient capacity, for example, is sufficient to supply the energy required for controlling the braking process.

Practical tests have shown that conveyors with control devices designed according to the invention are particularly suitable for operating at low voltages. For example, the central energy supply can easily be designed as an electrical low-voltage voltage source. If, for example, this energy supply supplies electrical energy with a voltage of at most 12 volts, the greatest possible degree of safety can also be guaranteed in an explosive environment. Accordingly, according to the invention trained conveyors, whose electrical supply takes place at such low operating voltages, all legal requirements as specified in the "ATEX standard". Accordingly, they are assigned to the category Ml defined in the aforementioned regulation. This category includes devices that are structurally designed and, if necessary, are additionally provided with special protective measures so that they can be operated in accordance with the parameters specified by the manufacturer and ensure a very high level of safety. The devices of category Ml are therefore suitable for use in underground mines and their surface systems which are endangered by mine gas and / or combustible dusts. Devices in this category must continue to be operated even in the event of rare device faults in an existing explosive atmosphere and therefore have explosion protection measures so that if a protective device measure fails, at least a second independent protective device measure guarantees the required safety or, if two independent errors occur, the required safety is still guaranteed becomes.

A particularly advantageous embodiment of the invention is characterized in that a control device is assigned to each braking device. The concept of decentralized control of the braking processes implemented in a conveyor device according to the invention designed in this way makes it possible to manufacture the braking device with the associated control device as a ready-made assembly. At the place of use, this module is only connected to the central energy supply and the control system necessary control lines connected. In this way, the effort for assembly, which often takes place under difficult conditions underground, is reduced to a minimum. Due to the reduced number of lines, the risk of malfunctions that can occur as a result of a cable break or the like is also minimized.

In this context, it is particularly favorable if the control device is connected to a central control and monitoring device via a data line. From this central control and monitoring device, information about the operating state of the conveyor, the operating parameters and the like can be transmitted to the respectively connected braking devices. However, it is also possible to dispense with a central control device. In this case, the control devices themselves can be enabled to directly exchange data with the other control devices of the conveyor.

The data line via which the control devices are connected to one another or to the central control unit is preferably a digital data bus to which a large number of control devices can be jointly connected without any problems. Via such a central data line, the information and control signals required for trouble-free operation can be exchanged quickly, safely and between the individual control devices themselves and between the control and monitoring device and the control devices, and with the lowest energy consumption. In addition to the actual control functions, the control devices can also perform monitoring functions in a conveyor according to the invention. Continuous speed monitoring can thus be carried out by means of the control device. Likewise, the control device can monitor the state of wear of the brake device assigned to it. In such cases, in which the braking device is operated by compressed air, the control device should also monitor the compressed air supply.

In a manner known per se (DE 198 37 315 Cl), the braking devices each comprise an elastic element, in particular a spring, which supplies the braking force required for the braking process, and there are braking elements which, during the braking process, act on one with the drive shaft of the respective drive device coupled brake disc act, an exact image of the respective functional state of the brake can be obtained in that the control device monitors the stroke position and / or the stroke time of the brake elements required during a braking operation.

Because the control device is equipped with an optical display, the respective operating status can be checked in a simple manner. This simple control option proves to be particularly advantageous in the often harsh environment when operating underground. The invention is explained in more detail below on the basis of a drawing illustrating an exemplary embodiment. They show schematically:

1 shows a section of a conveyor used underground,

Fig. 2 is a control device used on the conveyor shown in Fig. 1.

The conveyor 1 comprises a conveyor belt 2 on which the piece goods to be transported, for example overburden or coal, are conveyed. Drive devices 3, 4, 5, 6 are provided for driving the conveyor belt 2. The drive devices 3, 4, 5, 6 each drive a drive roller 7, 8 in pairs, the one drive device 3, 5 of the respective pair being arranged on one side and the other drive device 4, 6 of the same respective pair being arranged on the other side of the conveyor belt 2 is.

A brake disc 10 is rotatably connected to the drive shaft 9 of each drive device 3, 4, 5, 6. The respective brake disk 10 is part of a brake device 11, 12, 13, 14. Each drive device 3, 4, 5, 6 is assigned such a brake device 11, 12, 13, 14.

The braking devices 11, 12, 13, 14 can be designed in the manner known per se from DE 198 37 315 Cl. Accordingly, in addition to a brake disk 10, they each comprise brake calipers (not shown here in detail), which at their end assigned to the brake disk 10 during the braking process onto the braking surfaces wear brake pads acting on the brake disc. At their other end, the brake calipers are coupled in an articulated manner to the mutually adjustable housing halves of the brake devices 11, 12, 13, 14.

The braking force applied by the braking devices 11, 12, 13, 14 during the braking process is generated by a spring assembly, also not shown. In the idle state, this spring assembly is held pneumatically in a pretensioned state. The preload of the spring assembly is dimensioned such that a braking force sufficient for safe braking of the conveyor belt is available even under high loads.

The braking process is pneumatically controlled by means of a valve combination (not shown) in such a way that the movement of the conveyor belt 2 is delayed in a manner that is gentle on the material and adapted to the respective load. Likewise, the braking devices 11, 12, 12, 14 are released via the valve combination when the conveyor 1 is started up, in that the respective spring assembly is brought back into its pretensioned position by exposure to compressed air.

A control device 15, 16, 17, 18 is assigned to each of the braking devices 11, 12, 13, 14. The regulating devices 15, 16, 17, 18 each comprise a data processing unit 19 which is connected to a central data line 21 via a plug connector 20.

Furthermore, the data processing device 19 is arranged on one on the outside of the housing of the respective control devices 15, 16, 17, 18 Input device 22 connected. The control device can be reset to a defined initial state via the input device 22.

Via further plug connections 23, 24, 25, a sensor 26 for detecting the relative position of the housing halves of the respective braking device 11, 12, 13, 14 and a sensor 27 for detecting the speed of the drive shaft are connected to the respective control device 15, 16, 17, 18 the respective drive device 3, 4, 5, 6 and a sensor 28 for monitoring the compressed air supply, by means of which the springs of the braking devices 11, 12, 13, 14 are pretensioned in the idle state. The stroke position, the travel distances covered during the braking and releasing process and the lifting times that pass between the start and end of a braking or releasing process can be detected by means of the sensor 26.

Finally, control lines 29, 30 are connected to the data processing device 19. Via the control lines 29, 30, the function of valves 31, 32 is controlled, which relieve the spring of the respective braking device 11, 12, 13, 14 from the pneumatic force during the braking process or cause the spring to be pneumatically pressurized during the release process.

The electrical energy required for the operation of the data processing device 19 and the sensors 26, 27, 28 and valves 31, 32 connected to it is provided in normal operation by a central energy supply 33 to which each of the control devices 11, 12, 13, 14 is connected via a supply line 34. The power is supplied with a voltage of 12 volts. An electrical accumulator 36, which is also present in each control device 15, 16, 17, 18, is also connected to the central energy supply 33. The capacity of the accumulator 36 is dimensioned in such a way that the energy emitted by it is sufficient to prevent the central power supply from failing to supply the data processing device 19, the sensors 25, 26, 27 connected to it and the valves 31, 32 with electrical energy until a controlled braking process has been completed.

The central data line 21 forms a data bus, via which all control devices 15, 16, 17, 18 are jointly connected to a control and monitoring device 37. The control devices 15, 16, 17, 18 communicate with each other and with the control and monitoring device 37 digitally using a standardized communication protocol.

Finally, each control device 15, 16, 17, 18 has an optical status display 38 on which, for example by means of light-emitting diodes or comparable lighting devices, it is shown in which operating state the respective control device 15, 16, 17, 18 is currently located.

During normal conveying operation, the control and monitoring device 37 transmits the current operating parameters, such as set speed, number of drives in use, etc., to the control devices 15, 16, 17, 18. At the same time, it can Receive continuous information from the individual control devices 15, 16, 17, 18 about the current speed of the respective drive device 3, 4, 5, 6, the state of wear of the respective brake device 11, 12, 13, 14 and the proper functioning of the compressed air supply.

If the central energy supply 33 malfunctions, the regulating devices 15, 16, 17, 18 are automatically and without interruption supplied with electrical energy by the accumulators 36 assigned to them. The interruption of the central energy supply also automatically triggers a braking process. The energy provided by the accumulators 36 ensures that this braking process is also regulated by the respective control devices 15, 16, 17, 18, as would be the case if the central energy supply 33 were to function properly.

After completion of the braking process, the braking devices 11, 12, 13, 14 are held in the braking position by the braking force generated by the springs assigned to them until the central power supply 33 is in operation again and the control and monitoring device 37 sends a signal for releasing the Braking devices 11, 12, 13, 14 is given. REFERENCE NUMBERS

1 sponsor

2 conveyor belt

3, 4, 5, 6 drive devices 7,8 drive roller

9 drive shaft

10 brake disc

11, 12, 13, 14 braking devices

15, 16, 17, 18 control devices

19 data processing unit

20 connectors

21 data line

22 Input device 23, 24, 25 plug connections

26 sensor for detecting the relative position of the housing halves of the respective braking device 11, 12, 13, 14,

27 Sensor for detecting the speed of the

Drive shaft of the respective drive device 3, 4, 5, 6

28 Sensor for monitoring the

Air Supply

29, 30 control lines

31, 32 valves

33 Energy supply

34 supply line

36 accumulator

37 Control and monitoring device

38 optical status display

Claims

 P AT E N T AN S P RÜ C H E Device for conveying loose goods, such as belt or chain conveyors, - with a conveyor (2), such as a belt, belt or chain, with drive devices (3, 4, 5, 6) which are arranged along the conveying path covered by the conveying means (2), - With the drive devices (3, 4, 5, 6) associated braking devices (11, 12, 13, 14) for braking the conveyor (2), which automatically brake the conveyor in the event of a fault, and - With a control device (15, 16, 17, 18) connected to a central energy supply (33), which regulates the braking process carried out by the respective braking device (11, 12, 13, 14) each time the conveying means (2) is braked and with an energy store (36) is equipped, which they in the event of a fault in the central energy supply (33) is supplied with at least the energy required for controlling at least one braking operation of the braking device (11, 12, 13, 14) assigned to it. 2. Device according to claim 1, d a d u r c h g e k e n n z e i c h n e t, that each braking device (11, 12, 13, 14) is assigned a control device (15, 16, 17, 18). 3. Device according to one of the claims d a d u r c h g e k e n n z e i c h n e t that the central energy supply (33) is an electrical low-voltage voltage source. 4. Apparatus according to claim 3, d a d u r c h g e k e n n z e i c h n e t that s s s s supplies the energy supply (33) electrical energy with a voltage of at most 12 volts. 5. Device according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, that the energy storage is an electrical accumulator (36). 6. Device according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, that the control device (15, 16, 17, 18) controls the braking performed by the braking device (11, 12, 13, 14) regardless of the load. 7. Device according to one of the preceding claims, characterized in that each control device (15, 16, 17, 18) via a data line (21) with a common central Control and monitoring device (37) is connected. Device according to claims 2 and 6, d a d u r c h g e k e n n z e i c h n e t, to which a data line (21) a plurality of control devices (15, 16, 17, 18) can be connected. 9. Device according to one of claims 7 or 8, d a d u r c h g e k e n n z e i c h n e t d a s s the data transmission via the data line (21) takes place digitally. 10. Device according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, that the control device (15, 16, 17, 18) comprises a speed monitoring (27). 11. Device according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, that the control device (15, 16, 17, 18) monitors the state of wear of the brake device (11, 12, 13, 14) assigned to it. 12. Device according to one of the preceding claims, characterized in that the braking devices (11, 12, 13, 14) are operated by compressed air. 13. The apparatus of claim 13, d a d u r c h g e k e n n z e i c h n e t, that the control device (15, 16, 17, 18) monitors the compressed air supply. 14. Device according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, that the braking devices (11, 12, 13, 14) each have an elastic element, in particular a spring, which provides the braking force required for the braking process. 15. Device according to one of the preceding claims, characterized in that the braking device (11, 12, 13, 14) has braking elements, which during the braking process on a with the drive shaft of the respective drive device (3, 4, 5, 6) coupled brake disc (10 ) Act. 16. The apparatus of claim 14 and 15, d a d u r c h g e k e n n z e i c h n e t, that the control device (15, 16, 17, 18) monitors the stroke position of the brake elements. 17. The apparatus according to claim 14 and 15, characterized in that the control device (15, 16, 17, 18) monitors the stroke time of the braking elements required during a braking operation. 8. Device according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, that the control device (15, 16, 17, 18) comprises an optical operating status display.