FIELD OF INVENTION

[0001] The present disclosure, in general, relates to an instrument for real time monitoring in coal mines and in particular, to an instrument for real time monitoring of roof to floor convergence and/or any similar movements during depillaring process inside the coalmines.
BACKGROUND
[0002] Background description includes information that may be useful in understanding the present invention.
[0003] Depillaring with caving in coal mining processes is considered as one of the most risky operations owing to the reasons that underground coal mining is associated with unavoidable situations such as convergence or sagging of the roof or heaving of floor or similar movements of the roof in the goaved out area. Such roof movements do not necessarily provide enough prior physical indications or prior signals.
[0004] The conventional practice of monitoring any roof to floor movement in the goaved out area during depillaring involved use of wooden indicator prop at the goafedges, which was effective but carried its own limitations. The other physical symptoms which were earlier used as indications were for example sounds from goaf, crushing of pillar sides/corners etc. However, such a mechanism was always dependent on the experience of individuals working in the coalmines and those who had been dealing with such situations for a long period. Further, there is no distinctive visual indication with the bending of some of existing indicator props under abutment load. The judgment about reduction of pillar always lies with the experience of mining personnel based on their eye sight.
[0005] In the present times, a remote monitoring device has been in use for providing visual indications from goaf to warn men against impending roof fall and to take precautionary measure at the appropriate time. The existing technology is an Auto- Warning Tell Tale (AWTT) system that is used for roof to floor convergence and heaving but with certain limitations. AWTT has a major limitation that the instrument i.e. AWTT can record roof movements only within a certain range of anchored horizon generally within a height of 10.0 m. However, it is incapable of monitoring and recording any roof movement from horizon above 10.0 m or any movement near the floor area of the coalmine.
[0006] Therefore, in order to overcome the limitations of the existing provisions, there is need in the art to provide for a device.
OBJECTS OF THE DISCLOSURE
[0007] It is therefore the object of the invention to overcome the aforementioned and other drawbacks in prior systems used for monitoring convergence of roof or any similar movements during depillaring process inside the coalmines.
[0008] The principal objective of the present invention is to develop an instrument that provides a complete real time monitoring and indication of roof to floor convergence or any similar movements during depillaring process inside the coalmines.
[0009] Another object of the present invention is to develop an instrument having a large coverage area or a larger coverage range inside the coalmines.
[0010] Another object of the present invention is to provide for an instrument that is capable of monitoring any kind of closure including convergence from the roof or heaving from the floor inside the coalmine.
[0011] Another object of the present invention is to maintain the safety of mining personnel and safe operations during the depillaring process inside the coalmines.
[0012] Another object of the present invention is to provide for an economic and efficient instrument for real time monitoring of roof to floor convergence in the coalmines.
[0013] These and other objects and advantages of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred form of the present invention is illustrated.
SUMMARY
[0014] This summary is provided to introduce concepts related to an instrument for a complete real time monitoring of roof to floor convergence or any similar movements during depillaring process inside the coalmines.
[0015] The concepts are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0016] In an embodiment, the present disclosure relates to an instrument for real time monitoring during coal mining comprising a roof assembly consisting of an anchor with a base circular flange, an inner rod connected to a measuring scale by a connector, a hollow outer covering rod, wherein the top portion of the inner rod is inserted into the anchor and the bottom portion of the inner rod and the measuring scale are inserted into the covering rod and a base assembly consisting of a rectangular base flange, a pair of threaded outer steel rods placed diagonally on the base flange, a threaded inner steel rod placed at the centre of the base flange between the outer steel rods, an outer rod configured to cover the inner steel rod, a compression spring wrapped over the top portion of the inner steel rod and the outer rod, wherein, the covering rod is configured to cover a junction where the inner rod and measuring scale of the roof assembly are connected to the inner steel rod of the base assembly and the measuring scale is visible through a transparent surface on the covering rod.
[0017] In an aspect of the present disclosure, a Light Emitting Diode (LED) indicator is placed on the inner rod below the anchor in the roof assembly.
[0018] In an aspect of the present disclosure, the anchor is shaped in form of a cone with a bottom tubular structure.
[0019] In an aspect of the present disclosure, the diameter of the circular flange is in the range of 5.0 cm to 10.0 cm.
[0020] In an aspect of the present disclosure, the inner rod has a diameter in the range 2.0 cm to 3.0 cm and length in the range of 80 cm to 100 cm.
[0021] In an aspect of the present disclosure, the outer rod has a diameter in the range of 6.00 to 6.2 cm and length in the range of 70 cm to 80 cm.
[0022] In an aspect of the present disclosure, the threaded inner steel rod is connected to the measuring scale through a connector 104 having a length of 3.8 cm and diameter of 3.0 cm.
[0023] In an aspect of the present disclosure, the length of the inner steel rod is in the range 50 cm to 60 cm and diameter in the range 1 cm to 1.4 cm.
[0024] In an aspect of the present disclosure, the outer base rod of the base assembly is clamped to the outer steel rods by a pair of metallic clamps on each side of the outer base rod.
[0025] In an aspect of the present disclosure, the lower part of the covering rod is clamped to the outer steel rods by means of pair of metallic clamps on both sides of the covering rod.
[0026] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.
[0027] It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined to form a further embodiment of the disclosure.
[0028] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF DRAWINGS
[0029] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the description, serve to explain the disclosed principles. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system and/or methods in accordance with embodiments of the present subject matter are now described, by way of example only, and with reference to the accompanying figures, in which:
[0030] Figure 1 illustrates a schematic view of the structure of the instrument providing a complete real time monitoring of roof to floor convergence or any similar movements during depillaring process inside the coalmines in accordance with an embodiment of the present disclosure;
[0031] Figure 2 illustrates a schematic view of a circuit diagram of the indication and signalling system of the instrument in accordance with an embodiment of the present disclosure;
[0032] It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative systems embodying the principles of the present subject matter. Similarly, it will be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes, which may be substantially represented in a computer-readable medium and executed by a computer or processor, whether or not such computer or processor is explicitly shown.

DETAILED DESCRIPTION
[0033] The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to clearly communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0034] It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
[0035] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a", “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
[0036] In addition, the descriptions of "first", "second", “third”, and the like in the present invention are used for the purpose of description only, and are not to be construed as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" and "second" may include at least one of the features, either explicitly or implicitly.
[0037] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0038] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0039] The present instrument provides a highly visible and immediate signal and indication of excessive roof movements and floor heaving inside the goaf during underground coal mining. The instrument provides instant real-time warning signals to the mining personnel about roof to floor convergence occurring while mining from a remote distance to ensure safety of man and machine. The present mechanised Pillar extraction process is much faster as compared to the conventional mining and hence dependency is more on usage of the instrument as it is difficult to rely only on physical conditions and indications such as sound from goaf and physical observations for the impending roof falls. Usage of the present instrument helps in immediately withdrawal of men and machine in a situation of any roof movements or roof to floor convergence. The present instrument consists of LED indicators that keep blinking once any sagging of roof or heaving of floor is observed in the goaf area.
[0040] These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0041] The present subject matter relates to an instrument for a complete real time monitoring of roof to floor convergence or any similar movements during depillaring process in underground coal mining. The instrument is placed at the junction where the top portion of the instrument is pushed into the roof area of the junction and the bottom portion rests or placed on the floor area of the junction inside the coal mine so that any movement or convergence between the roof and floor is detected and the alert signal is given away in a timely manner.
[0042] As illustrated in Figure 1, the instrument includes a roof assembly and a base assembly. The roof assembly consists of a conical shaped anchor 101 with a base circular flange 102 and a lower tubular portion, an inner rod 103 connected to a measuring scale 106 by a connector connecting the inner rod 103 to the measuring scale 106. The measuring scale 106 has a copper pointer and the measuring scale 106 is connected to the LED placed in a cap which is fitted on the surface of the inner rod.
[0043] The top assembly includes a hollow outer covering rod 105 connected to the bottom portion of the inner rod 103 such that the top portion of the inner rod 103 is inserted into the anchor 101 and the bottom portion of the inner rod 103 along with the measuring scale 106 are inserted into the covering rod 105.
[0044] With further reference to Figure 1, the base assembly consists of a rectangular base flange 107, a pair of threaded outer steel rods 108a, 108b, a threaded inner steel rod 109 placed at the centre of the base flange 107 between the outer steel rods 108a, 108b, an outer rod 110 configured to cover the inner steel rod 109, a compression spring 111 wrapped on the top portion of the inner steel rod 109 and the outer rod 110. The outer steel rods 108a, 108b are placed diagonally on the base flange 107 for aligning the inner steel rod 109 and the outer rod 110 in a straight orientation. The outer steel rods 108a, 108b hold the outer rod 110 through metallic clamps by a pair of metallic clamps on each side of the outer base rod 110.
[0045] The covering rod 105 of the roof assembly acts as cover and is configured to cover a junction where the inner rod 103 and the measuring scale 106 of the roof assembly are connected to the inner steel rod 109 of the base assembly. The measuring scale 106 is visible through a transparent surface 112 on the covering rod 105 where the movement of the pointer on the scale is observed during the working of the real time monitoring instrument. The structural material of the instrument includes a variety of Polyvinyl Chloride (PVC) based materials or similar materials which makes it economically viable and cost effective too.
[0046] The following table 1 illustrates the range of dimensions of the aforementioned parts of the real time monitoring instrument as follows:
Table 1: Dimensions of the different parts of the Real time monitoring instrument
S.N. Description Dimension
1 Length of anchor 10.0 cm
2 Diameter of circular base flange 10.0 cm
3 Length of inner rod of roof assembly 100 cm
4 Diameter of inner rod of roof assembly 3.0 cm
5 Length of outer covering rod 70 cm
6 Diameter of outer covering rod 6.2 cm
7 Dimensions of the rectangular base flange (L x B x H) 18 cm x 8 cm x 2 cm
8 Length of threaded outer steel rods 75 cm (Two) & 100 cm (One)
9 Diameter of threaded outer steel rods 1.4 cm
10 Length of threaded steel inner rod 50.0 cm
11 Diameter of threaded steel inner rod 1.4 cm
12 Length of compression spring 20.0 cm
13 Length of outer rod of base assembly 30.0 cm
14 Diameter of outer rod of base assembly 3.0 cm
15 Inner diameter of measuring scale 2.5 cm

Working Example-
[0047] The instrument for real time convergence monitoring is installed between the roof and floor of a junction in underground by keeping its rectangular base flange 107 onto the floor and anchoring the top part in the roof. The base circular flange 102 touches the base of the roof surface and the rectangular base flange 107 is placed on the floor area in the underground coal mine. In cases, where the anchor 101 is pushed at a height >2.0 m then an extension pieces are attached to the anchor 101 for correct placement of the anchor 101 into the roof.
[0048] Once the instrument is set-up at the junction, the instrument performs a real time monitoring of any convergence or movement between the roof and the floor during and after extraction of coal. The instrument is set with predefined warning limits of 5 mm & 10 mm. If any movement takes place beyond the set warning limit in the instrument, the copper pointer starts moving on the measuring scale 106 connected directly to the LED indicator. Upon a movement of the copper pointer on the scale, the LED starts blinking and thus, sends a warning signal during the underground coal mining process for the safety of men and machines. The preliminary warning signal turns into Green colour once the instrument gets convergence of 5 mm and keeps blinking. As the roof to floor convergence reaches 10 mm, the two LEDs (Green & Red) starts blinking alternately. This gives clear visual indication of distinctive roof to floor movements for the workers for safety and taking necessary precautions.
Technical advantages:
[0049] With the present instrument installed and monitored, it is possible to monitor continuously any roof to floor movement inside the goaf area.
[0050] With the present disclosure, it is feasible to have a visual signal or indication of roof convergence or floor heaving from a safe and remote distance on real-time inside the coalmine during depillaring process.
[0051] With the present disclosure, it is possible to attain an efficient mechanized mining process.
[0052] With the present disclosure, it is possible to ensure complete safety of mining personnel through a real time monitoring and signalling system.
[0053] With the present disclosure, it is possible to have a flashing signal system even beyond a distance of 20 m from the goafedge.
[0054] With the present disclosure, it is easier to set a site specific warning limit rather a fixed setting in the instrument.
[0055] With the present disclosure, there is no requirement of complex cable structures, as the present instrument is easy to install, simple in operation, and easy to understand for all levels of workers.
[0056] With the present disclosure, it is feasible to take immediate spot decisions with regard to withdrawal of men and machine from the goaf area in the coalmines.
[0057] With the present disclosure, it is possible to estimate valuable information about the status of sagging of roof in the goaf with respect to the level of extraction per pillar during the depillaring process.
[0058] It should be understood, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise, as apparent from the discussion herein, it is appreciated that throughout the description, discussions utilizing terms such as “receiving,” or “determining,” or “retrieving,” or “controlling,” or “comparing,” or the like, refer to the action and processes of an electronic control unit, or similar electronic device, that manipulates and transforms data represented as physical (electronic) quantities within the control unit’s registers and memories into other data similarly represented as physical quantities within the control unit memories or registers or other such information storage, transmission or display devices.
[0059] Further, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.
[0060] It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.
[0061] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.
[0062] Reference Numerals
Reference Numeral Description
101 Anchor
102 base circular flange
103 inner rod
104 Connector
105 covering rod
106 measuring scale
107 Base flange
108a, 108b Outer steel rods
109 Inner steel rod
110 Outer base rod
111 compression spring
112 Transparent surface

WE CLAIM:

1. An instrument for real time monitoring of roof to floor convergence during coal mining, the instrument comprising:
a roof assembly consisting of an anchor (101) with a base circular flange (102), an inner rod (103) connected to a measuring scale (106) by a connector (104), a hollow outer covering rod (105), wherein the top portion of the inner rod (103) is inserted into the anchor (101) and the bottom portion of the inner rod (103) and the measuring scale (106) are inserted into the covering rod (105); and
a base assembly consisting of a rectangular base flange (107), a pair of threaded outer steel rods (108a, 108b) placed diagonally on the base flange (107), a threaded inner steel rod (109) placed at the centre of the base flange (107) between the outer steel rods (108a, 108b), an outer rod (110) configured to cover the inner steel rod (109), a compression spring (111) wrapped on the top portion of the inner steel rod (109) and the outer rod (110),
wherein, the covering rod (105) is configured to cover a junction where the inner rod (103) and measuring scale (106) of the roof assembly are connected to the inner steel rod (109) of the base assembly and the measuring scale (106) is visible through a transparent surface (112) on the covering rod (105).
2. The instrument as claimed in claim 1, wherein a LED indicator is placed on the inner rod (103) below the anchor (101) in the roof assembly.
3. The instrument as claimed claim 1, wherein the anchor (101) is shaped in form of a cone with a bottom tubular structure.
4. The instrument as claimed in claim 1, wherein the diameter of the circular flange (102) is in the range of 5.0 cm to 10.0 cm.
5. The instrument as claimed in claim 1, wherein the inner rod (103) has a diameter in the range 2.0 cm to 3.0 cm and length in the range of 80 cm to 100 cm, the outer rod (105) has a diameter in the range of 6.00 to 6.20 cm and length in the range of 70 cm to 80 cm.
6. The instrument as claimed in claim 1, wherein the threaded inner steel rod (109) is connected to the measuring scale (106) through a connector (104) having a length of 3.8 cm and diameter of 3.3 cm.
7. The instrument as claimed in claim 1, wherein the length of the inner steel rod (109) is in the range 50 cm to 60 cm and diameter in the range 1 cm to 1. 4 cm.
8. The instrument as claimed in claim 1, wherein the outer base rod (110) of the base assembly is clamped to the outer steel rods (108a, 108b) by a pair of metallic clamps on each side of the outer base rod (110).
9. The instrument as claimed in claim 1, wherein the lower part of the covering rod (105) is clamped to the outer steel rods (108a, 108b) by means of pair of metallic clamps on both sides of the covering rod (105).
10. The instrument as claimed in claim 1, wherein the instrument is made up of Polyvinyl Chloride (PVC) or similar plastic based materials.