US3346299A

US3346299A - Drilling device with means to indicate resistance to rotation

Info

Publication number: US3346299A
Application number: US412069A
Authority: US
Inventors: Meyer Otto
Original assignee: Demag AG
Current assignee: Mannesmann Demag AG
Priority date: 1963-11-20
Filing date: 1964-11-18
Publication date: 1967-10-10
Anticipated expiration: 1984-10-10
Also published as: DE1232901B; GB1010034A

Description

Oct. 10, 1967 o. MEYER 3,345,299

DRILLING DEVICE WITH MEANS TO INDICATE RESISTANCE TO ROTATION Filed Nov. 18, 1964 H6. 3 F/G.4

INVHW'OP O TTO I"! E /E R United States Patent 3,346,299 DRILLING DEVICE WITH MEANS T0 INDI- CATE RESISTANCE T0 ROTATION Otto Meyer, Mulheim (Ruhr), Germany, assignor to Demag Alrtiengesellschaft, Duisburg, Germany Filed Nov. 18, 1964, Ser. No. 412,069 Claims priority, application Germany, Nov. 20, 1963,

42,982 Claims. (Cl. 299-1) This invention relates in general to a drilling apparatus and in particular to a new and useful device for drilling particularly tunnels, drifts or other ground or earth excavations employing means for visually indicating the working resistance of the drilling tools for the purpose of controlling the drilling operation.

When driving tunnels, drifts and even in the drilling of vertical or oblique drilling excavations in the ground or the rock by use of a drilling device having a plurality of tools such as drills, cutters, blades, shovels and the like, it is usual that some of the tools will encounter areas of increased resistance due to a very hard formations which will make the affected tools blunt in a short time or even destroy them completely. For example, when rocks or metallic foreign bodies are found in the ground, the rocks may contain elements of particular hardness and particular tools of the overall drilling apparatus may strike on such hard elements which may even include petrification or iron girders which have remained from previous drillings. In some instances it is even possible that the drilling operation may cause the striking of an undetected bomb which further increases the danger of the drilling operation.

In the devices presently known for drilling large openings such as tunnels, it is difficult, if not impossible for the operator to determine when the drilling apparatus will encounter areas of increased resistance because the operators view is concealed almost entirely by the rotary tool holder. In some cases it is necessary to interpose pressure chambers, especially where water breaks-in are anticipated. Such pressure chambers are only accessible through special gates or openings and thus it is impossible to observe the forward ground or rock to be drilled. When using prior art drills it was thus very likely that these unexpected resistance areas would be encountered and this would result in a long term and annoying stoppage with the resultant expense in respect to the loss of time and the requirements of the replacement of tools.

The present invention deals with a device by which the areas of increased resistance can be rapidly indicated, recognized and located, so that the work can be stopped before the tools have been blunted or destroyed or other dangers appear. A particularly hard foreign body can be drilled out by special tools or pealed out (i.e. removed by first removing the surrounding substances to release it) or crushed. After the foreign body is thus pulled away, the work can be resumed Without replacing or resetting the cutting tools.

In accordance with a preferred arrangement of the invention, the working resistance encountered by each of the tools or by selected ones of the tools which will be indicated by the cutting pressure encountered, the drilling pressure, the torque in rotating a rotary drill, the current intensity for driving the rotary drill etc. is measured, either mechanically, hydraulically, electrically, or magnetically and either continuously or at fixed intervals and the measuring result is transmitted to indicating means for visually indicating variations in these working resistance measuring elements which are encountered by the selected drills. In a preferred arrangement the results are transmitted to a revolving synchronous device which in the simplest form may include light producers or 'ice each bulb. With such an apparatus it is possible to have a ready indication of the areas of specific resistance on the front of the tunnel being driven made visible on the synchronous device by increased or reduced light intensity. The arrangement is particularly desirable for those tools which are driven at particularly high speeds.

When the overall tool which is boring the tunnel is moved at a lower speed the synchronous device should advantageously include fluorescent screen having a persistence effect so that the light which is emitted from the bulbs which represent the particular drills will remain on the screen for a longer period of time. This may, for example, comprise a luminous strip or luminous spot (light and dark spots) which are obtained and can be recognized according to type and intensity and by means of which the location, the extent and the hardness of the foreign body can be measured or at least estimated.

In a preferred arrangement the synchronous device advantageously includes a rotatable disc having a number of bulb elements, corresponding to the number of drills being employed by the rotary drilling tool, which are mounted on the synchronous device or disc for rotation at the same speed as the work holder of the drill. For tools that move at a lower speed it is advisable to use a fluorescent screen so that the light emitted from the synchronous device remains for a longer period of time. The synchronous device or disc is put into rotation mechanically by the revolving tool disc or by its drive or by means of an electric sychronizing drive. In some instances it is preferred that the rotary synchronizing element be a disc of the same nature as the tool holder in which each of the rotary drills are mounted. Instead of incandescent bulbs, a fluorescent screen can be used or a similarly designed braun tube or other known optical means.

In some instances it is desirable to provide means on each of the tools such as scanning elements which measure the resistance, the feed or other suitable quantities, to increase the number of light producers, and thus the number of light points and provide a sufficient picture of the extent and location of the area of increased resistance, even with a smaller number of tools. The synchronous device, such as a rotary disc having the light bulbs corresponding to the individual tools mounted on a rotary tool holder, is preferably arranged on a control stand behind a fluorescent screen which may be easily observed by the operator. The overall effect of this device advantageously is such as to give a visual light indication of the appearance of a heavy resistance area which is being encountered by the rotary drill.

Accordingly it is an object of the invention to provide a drilling apparatus which includes a rotary holder having a plurality of rotatable drills projecting outwardly from the holder at radially spaced locations and with indicating means connected to selected ones of the drills and responsive to a change in the resistance encountered by such drills in the drilling operation to vary an indication such as a light which may be easily viewed by the operator of a drill.

A further object of the invention is to provide a tunnel drilling device comprising a rotary drilling tool including a rotary plate or disc having a plurality of rotary drilling elements thereon arranged in a plurality of radially spaced locations, with a rotary synchronous element having visual indicating means thereon such as light bulbs connected to the rotary drill and rotatable in timed sequence thereto, and including electrical means connected to each of the rotary drills and to the indicating means to vary the indications in accordance with the resistance encountered by the drills during the drilling operation.

A further object of the invention is to provide a rotary drilling device including means for visually indicating the magnitude of the resistance being encountered by a plurality of individual drilling elements on a screen in a position for continuous viewing by an operator.

A further object of the invention is to provide a device for drilling in the earth which is simple in design, rugged in construction and economical to manufacture.

The various features of novelty which characterize the the invention are pointed out With particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated and described a preferred embodiment of the invention.

In the drawings:

FIG. 1 is a side elevational view of a cutting head having milling cutters;

FIG. 2 is a somewhat schematic transverse sectional view of a complete operational drill constructed in accordance with the invention;

FIG. 3 is a front elevational view of a signal rotor or synchronous device; and

FIG. 4 is a front elevational view of the fluorescent or indicating screen.

Referring to the drawings in particular, the invention embodied therein comprises a tunnel drilling apparatus including a rotary tool holder or a disc it which is secured to a rotatable shaft 5 for rotation therewith. On the disc 1 are arranged in three separate radial rows, a plurality of milling tools or rotary drill elements 2 each having a driving motor 3. The disc or holder 1 is driven by a shaft 5 which in turn is rotated by means of a device such as a motor 4.

In the drilling apparatus indicated there is provided an end plate 6 located at an inwardly spaced location from the rotary drill holder 1 and defining a pressure chamber 7 therebetween. The pressure chamber 7 is maintained under a positive pressure distinct from that in the space with the operators seat 12 and it is accessible through a gate formation 8 defined in the end plate 6. The rotary holder 1 is also provided with a shovel device 10, which is schematically indicated and which provides means for conveying or removing the material which is excavated through the end plate 6 in the direction of the arrow 11. The operator of the drill will normally be positioned inside or inward of the end plate 6 and at such location it is impossible to see the resistance which is being encountered by each of the drill elements 2.

In accordance with the invention a measuring and signal sequence is provided to permit the operator to observe any special resistances which may be encountered by the operation. The apparatus advantageously includes measuring instruments provided for each of the tools 2 or on a part connected to them, for example, on the drive 3 for the machines, in order to measure the working resistance which is encountered by each tool. The working resistance can of course be measured, such as by an increase in the power required to drive the tools, by direct measurement of the torque acting on the shaft driving the drills, or by a measurement of the driving power required which may be measured, for example, by hydraulic, pneumatic or electrical means. Torque indicators are known in several models for all of these arrangements.

An example of one means for measuring the resistance exerted by the solid face shoulder of the tunnel on the individual milling cutters is a measurement of the current consumption of each of the individual driving motors 3 of the milling cutters. Thus, the measuring instrument 15 may comprise in a simple case a simple ammeter. The indications on the ammeters 15 may be transformed as electrical signals to correspondingly vary the intensity of the light indicators 20 of the synchronizing disc 19. In FIG. 2, a multi-cable electrical connection 5a for separately connecting each of the instruments through the collector 17 to the amplifier 22 is shown as extending through the shaft 5.

In accordance with the invention the measuring units 15 are connected electrically through connecting lines 16 which extend along the shaft 5 and which are connected individually to respective current collector elements 17 spaced along the shaft. There is provided one current collector 17 for each of the rotary drills Z.

From the same shaft 5 is taken a mechanical drive 18 which rotates a synchronous device such as a rotatable disc 19 at a rotational speed in proportion to the rotation of the holder i. The disc 19 is provided with a plurality of light bulbs or electrical indicating means arranged in three radial rows with a separate indicating means being aligned on the disc 19 in the same relative location as the tools 2 are aligned on the work holder ii.

The current flowing through the collectors 17 varies in accordance with the changes in working resistance encountered by the tools 2 and this current signal is amplified by the amplifier 22 and each amplified signal is connected individually to a respective electrical indicator or bulb 20 corresponding to the particular affected rotary drill tool. Signals may be set, for example, so that the bulbs 23 will light up to a brighter intensity when the resistance encountered by the associated rotary drill 2 is increased.

The operator will normally sit in the seat indicated 12 in front of a fluorescent screen 25 and thus he can recognize by the brightening of the bulbs at certain points of their path the position and perhaps also the extent of a foreign body having a particularly great cutting resistance which may be encountered by the drill. When the holder 1 is revolved at relatively slow speed it is advisable to arrange a fluorescent afterglow screen 25 having a persistence effect, for example, a screen having a phosphorescent coating in front of the synchronizing disc. In this manner the screen 25 will hold the light effect when the bulbs pass by the point of increased resistance until they again pass by the same point and the light effect will be widened somewhat so that a light spot and dark spot 25a is formed Which informs the operator rapidly about the position, size and form of the piece causing the resistance. The dark spot 25a represents an area of greater brightness on the afterglow screen 25. The light sources 20 arranged according to the cutters 2 of FIG. 1 are mounted on a supporting disc 19 (FIG. 3) which rotates in synchronism with the cutter disc 1 and the light sources light up brighter when the associated drills encounter a region of higher resistance than those whose associated drills encounter normal resistance. This increased light in a particular area forms an afterglow effect on the screen 25 providing a visual indication of the location of the high resistance areas.

Instead of driving the indicator mechanically from the shaft 5 or from the drive 4 it is sometimes preferable to provide a separate drive which may be operated in synchronism with the disc 1, for example electrically, such as by using a selsyn motor and a selsyn transmitter. It should also be appreciated that there are other electrical indicators besides bulbs and any device which will emit radiation or energy impulses may be employed on the revolving disc 19.

With slowly rotating tool discs It the light effect can be increased on the optical device, if necessary. This lighting effect, for example, may be increased by rotating the device faster than the tool disc.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. A drilling device comprising a rotary drill holder, means for rotating said drill holder, a plurality of rotary drills mounted for rotation on said drill holder at a plurality of angularly spaced locations, means to rotate said drills, electrical means connected to each of said drills transmitting an electrical signal varying in intensity only in proportion to the intensity of the resistance to rotation encountered by the associated drill during its rotation as aifected by the substance which it encounters during drilling, and visual indicating means connected to said electrical means and visually indicating the resistance encountered by each drill at each position of its rotary movement along with rotation of said holder.

2. A drilling device comprising a rotary drill holder, means for rotating said drill holder, a plurality of rotary drills mounted fo rotation on said drill holder at a plurality of angularly spaced locations, means to rotate said drills, electrical means connected to each of said drills transmitting an electrical signal varying in intensity in proportion to the intensity of the resistance to rotation encountered by the associated drill during its rotation as affected by the substance which it encounters during drilling, and visual indicating means connected to said electrical means and visually indicating the resistance encountered by each drill at each position of its rotary movement along with rotation of said holder, including a rotary disc element, means for rotating said disc at a speed proportional to the speed of rotation of said holder and electrical indicators on said rotary element of a number and a location corresponding to the number and location of said drills on said holder.

3. A drilling device comprising a rotary drill holder, means for rotating said drill holder, a plurality of rotary drills mounted for rotation on said drill holder at a plurality of angularly spaced locations, means to rotate said drills, electrical means connected to each of said drills transmitting an electrical signal varying in intensity in proportion to the intensity of the resistance to rotation encountered by the associated drill during its rotation as affected by the substance which it encounters during drilling, and visual indicating means connected to said electrical means and visually indicating the resistance encountered by each drill at each position of its rotary movement along with rotation of said holder, including a rotary disc element, means for rotating said disc at a speed proportional to the speed of rotation of said holder, electrical indicators on said rotary disc element of a number and a location corresponding to the number and location of said drills on said holder, and a screen disposed adjacent said holder in a position to be influenced by the variations of electrical indications on said disc for giving a visual indication thereon.

4. A drilling device according to claim 3 wherein said screen has a characteristic of retaining light when it is received thereby, said electrical indicators on said disc comprising light indicators.

5. A drilling device comprising a rotary drill holder, means for rotating said drill holder, a plurality of rotary drills mounted for rotation of said drill holder at a plurality of angularly spaced locations, means to rotate said drills, electrical means connected to each of said drills transmitting an electrical signal varying in intensity in proportion to the intensity of the resistance to rotation encountered by the associated drill during its rotation as effected by the substance which it encounters during drilling, and visual indicating means connected to said electrical means and visually indicating the resistance encountered by each drill at each position of its rotary movement along with rotation of said holder, said rotary drill holder having three equally spaced radial rows of said drills, said visual indicating means including a rotary disc having lights thereon arranged in three equally spaced radial rows of lights with each light in a row corresponding in position to a respective drill in a row on said holder, and means for rotating said disc at a speed proportional to the speed of rotation of said holder.

6. A drilling device comprising a rotary drill holder, means for rotating said drill holder, a plurality of rotary drills mounted for rotation on said drill holder at a plurality of angularly spaced locations, means to rotate said drills, electrical means connected to each of said drills transmitting an electrical signal varying in intensity only in proportion to the intensity of the resistance to rotation encountered by the associated drill during its rotation as affected by the substance which it encounters during drilling, and visual indicating means connected to said electrical means and visually indicating the resistance encountered by each drill at each position of its rotary movement along with rotation of said holder, said rotary drill holder comprising a substantially disc shaped forward wall, an end plate spaced from said forward wall and defining adjacent the end plate and said forward wall a pressure chamber, an operators station outside of said pressure chamber, said visual indicating means being located adjacent said operators station for permitting the operator to visually observe changes in resistance encountered by the drills during the drilling operation.

7. A drinking device comprising a rotary disc-shaped drill holder, means for rotating said drill holder, a plurality of drills rotatably mounted on said holder at a plurality of angularly spaced locations, means to rotate said drills including electrical drive means for each of said drills, electrical means connected to each drive means of said drills and responsive to said drive means for transmitting an electrical signal varying in intensity only in proportion to the intensity of the resistance encountered by the associated drill during its rotation as afiected by the substance which is encountered during drilling, and visual indicating means connected to said electrical means to indicate visually variations in resistance encountered by each drill at each location of its movement during rotation of said rotary drill holder.

8. A drilling device comprising a rotary drill holder, means for rotating said drill holder, a plurality of drills rotatably mounted on said holder at a plurality of angularly spaced locations, means to rotate said drills, electrical means connected to each of said drills transmitting an electrical signal varying in intensity in proportion to the intensity of the resistance encountered by the associated drill during its rotation as affected by the substance which is encountered during drilling, visual indicating means connected to said electrical means to indicate visually variations in resistance encountered by each drill at each location of its movement during rotation of said rotary drill holder, means to rotate said rotary drill holder, said indicating means including a rotary disc, and means connected between said means to rotate said rotary drill holder and said rotary disc to rotate said rotary disc at a speed in proportion to the speed of rotation of said holder, said indicating means including a plurality of indicating lights on said disc of a number corresponding in number and location to the drills on said holder, whereby when said holder and said disc are rotated, the intensity of light on said lights on said disc is a visual indication of resistance being encountered by each of the drills on said holder.

9. A drilling device comprising a rotary drill holder, a plurality of rotary drills mounted for rotation on said drill holder at a plurality of angularly spaced locations, means to rotate said drills, electrical means connected to each of said drills transmitting an electrical signal varying in intensity only in proportion to the intensity of the resistance to rotation encountered by the associated drill during its rotation as affected by the substance which it encounters during drilling, and visual indicating means connected to said electrical means and visually indicating the resistance encountered by each drill at each position of its rotary movement along with rotation of said holder, an elongated driving shaft for said holder,

said holder being a disc secured to the front end of said driving shaft for positioning said front end in a location to drill forwardly, means to rotate said shaft, said electrical means including a plurality of current collectors spaced along the axis of said shaft of a number correspending in number to the number of said rotary drills and each collector being connected to an associated one of said drills, amplifier means connected to said collectors for amplifying the signal produced by said electrical means, said amplifier means being connected to said visual indicating means for amplifying an electrical visual indication of the variations in resistance encountered by said rotary drills.

10. A drilling device comprising a rotary drill holder, a plurality of drills rotatably mounted on said holder at a plurality of angularly spaced locations, means to rotate said drills, electrical means connected to each of said drills transmitting an electrical signal varying in intensity in proportion to the intensity of the resistance encountered by the associated drill during its rotation as affected by the substance which is encountered during drilling, and visual indicating means connected to said electrical means to indicate visually variations in resistance encountered by each drill at each location of its movement during rotation of said rotary drill holder, said rotary drill holder comprising a relatively large disc positioned in the forward end of an excavation being drilled, an elongated shaft extending substantially axially through the excavation being drilled and connected at its forward end to said rotary drill holder, means to rotate said shaft, an end plate spaced from said rotary drill holder and defining between said rotary drill holder and said end plate a pressure chamber, an operators station located out of said pressure chamber, a plurality of electrical collectors spaced along said shaft on the exterior of said pressure chamber, means connecting said electrical means to said collectors, amplifier means connected to said collectors for amplifying the signal directed to said collectors by said electrical means, said visual indicating means comprising a rotary disc, drive means connecting said rotary disc to said shaft for rotating said disc in proportion to the speed of rotation of said holder, a plurality of lights on said disc of a number and location corresponding to the number and location of said drills on said holders, said lights each being connected through said amplifying means to respective collectors connected to respective ones of said drills, and a fluorescent screen spaced from said disc in a position to be influenced by the variations in light on the light bulbs held by said disc and being located adjacent said operators station for providing a visual indication of the variations in resistance encoun tered by the drills during their rotary movement along with such holder.

References Cited UNITED STATES PATENTS 1,859,814 5/1932 Wyckotf 73-436 X 2,620,386 12/1952 Alspaugh et al. 17550 X 2,752,591 6/1956 Felbeck et al. 17550 X 2,790,968 4/1957 Cook et al. 17550 X 2,826,402 3/1958 Alspaugh et al 2991 2,959,405 11/1960 Felbeck 299-1 3,195,661 7/1965 Jackson et al. 17595 OTHER REFERENCES Oberg, Erik et al.: Machinerys Handbook, 15th Ed, N.Y., Industrial Press, 1957, page 1835.

CHARLES E. OCONNELL, Primary Examiner.

I. A. CALVERT, Assistant Examiner.

Claims

1. A DRILLING DEVICE COMPRISING A ROTARY DRILL HOLDER, MEANS FOR ROTATING SAID DRILL HOLDER, A PLURALITY OF ROTARY DRILLS MOUNTED FOR ROTATION ON SAID DRILL HOLDER AT A PLURALITY OF ANGULARLY SPACED LOCATIONS, MEANS TO ROTATE SAID DRILLS, ELECTRICAL MEANS CONNECTED TO EACH OF SAID DRILLS TRANSMITTING AN ELECTRICAL SIGNAL VARYING IN INTENSITY ONLY IN PROPORTION TO THE INTENSITY OF THE RESISTANCE TO ROTATION ENCOUNTERED BY THE ASSOCIATED DRILL DURING ITS ROTATION AS AFFECTED BY THE SUBSTANCE WHICH IT ENCOUNTERS DURING DRILLING, AND VISUAL INDICATING MEANS CONNECTED TO SAID ELECTRICAL MEANS AND VISUALLY INDICATING THE RESISTANCE ENCOUNTERED BY EACH DRILL AT EACH POSITION OF ITS ROTARY MOVEMENT ALONG WITH ROTATION OF SAID HOLDER.