US3322466A - Mining machine with concentric relatively variably rotated heads - Google Patents

Description

y 1967 w MENNEKES 3,322,466

MINING MACHINE TWITH CONCENTRIC RELATIVELY VARIABLY ROTATED HEADS Filed Dec. 18 1964 22 Fig.2 7

IN VE N TOR WnuER Mgmvrxrs B s, Dam 8,4... Efrain/(Y5 I v United States Patent 3,322,466 MINING MACHINE WITH CONCENTRIC RELA- TIVELY VARIABLY ROTATED HEADS Werner Mennekes, Weidenkamp, Germany, assignor to Gewerkschaft Eisenhutte Westfalia, Wethmar, near Lunen, Westphalia, Germany, a corporation of Germany Filed Dec. 18, 1964, Ser. No. 419,329 Claims priority, application Germany, Dec. 30, 1963, G 39,495 3 Claims. (Cl. 299-60) This invention relates in general to mineral-winning machines, or drifting machines, such as are used in mining operations, and more particularly to a winning machine having rotary cutter heads driven in counter-rotation at selected individual speeds to compensate for the reaction effects encountered in mineral winning.

I the operation of rotary cutting winning machines, mineral is won, or cut free from mineral-bearing strata by the combined cutting, scraping .and striking action of chisel-like cutters extending from rotating cutter heads. These cutter heads and their associated driving means are customarily supported on a machine frame which can be advanced in desired directions for extended mineral removal.

Because of the contact between the moving cutters and the mineral deposit, considerable reaction forces and moments are imposed upon the cutter heads and are transmitted therethrough to the entire machine.

The effect of these forces and moments has resulted in considerable difficulty in guiding the mining machines in a desired direction of advancement, and in reliably maintaining a given direction of advancement.

Where it is desired to provide compensation for such reaction effects in a rotary cutter winning machine, it is necessary to provide at least two counter-rotating cutter heads so that the reaction forces and moments imposed upon one can be used to counterbalance and there by compensate for the reaction forces and moments imposed upon the other(s).

Such compensation has been attempted in certain prior art winning machines, but without success because of the varying resistance of the mineral encountered in typical mining operations. In general, the reaction forces and moments experienced by a given rotary cutter head are dependent upon the physical resistance properties of the mineral being won, the peripheral speed of the cutters, and the cutting feed rate.

It should be noted that in certain prior are winning machines, using rotary cutters operating at a relatively high speed, the reaction forces and moments are substantially lower and can be controlled within limits by conventional means. However, since such conventional reaction control means are essentially restricted to highspeed rotary winning machines, they are of little use in the more advantageous low-speed winning machines wherein considerably greater reaction loads are encountered. Furthermore, in many applications, the use of highspeed winning machines would be undesirable because of the size of the mineral fragments produced and the hazards of flying fragments. This is especially true in coal mining.

The winning machine acording to the instant invention is adaptable to both low-speed and high-speed operation as well, since it accomplishes its function of winning reaction compensation by controlling the relative peripheral speed of its counter-rotating cutter heads, and not by mere counter-rotation of the cutter heads alone, as in prior art winning machines.

As will be described in greater detail hereinafter, by controlling the peripheral speeds of the individual rotary cutter heads in relation to each other, the net force and moment exerted on the entire machine can be adjusted so as to cause it to advance in a selected direction, precisely guided under the influence of said net force and moment.

Control of the peripheral speeds of the individual cutter heads in the winning machines, according to one embodiment of the invention, is achieved by driving them through a gear drive mechanism having one output drive shaft connected to each cutter head, and gear shifting means for varying the transmission ratio between each out-put shaft and a single input drive shaft which is connected to a rotary prime mover.

According to another embodiment of the invention, the peripheral speeds of the rotary cutter heads, and hence the net force and moment acting on the Winning machine, are controlled by individual variable speed drives connected to each cutter head via gearing. This particular embodiment lends itself readily to conventional automatic control devices for establishing the peripheral cutter speeds required for a given direction of advancement.

According to other and further embodiments of the winning machine of the instant invention, the control and utilization of the aforesaid winning reaction effects can also be achieved by varying the relative spatial and angular disposition of the cutter head axes of rotation.

It is therefore an object of the invention to provide a rotary cutting winning machine wherein the net effects of the winning reaction forces can be controlled.

Another and further object of the invention is to provide a winning machine as aforesaid, wherein the controlled reaction forces can be utilized for the precise and reliable guidance of the machine in a selected direction of advancement.

Still another and further object of the invention is to provide a winning machine as aforesaid, which is adaptable for both low-speed and high-speed operation.

Other and further objects and advantages of the winning machine, according to the invention, will appear in, or become evident from the following detailed descrip: tion and accompanying drawings in which:

FIG. 1 is a longitudinal view, partly in section, of a winning machine, according to another embodiment of the invention, shown apart from its associated machine frame;

FIG. 2 is a longitudinal view, partly in section, of a winning machine, according to another embodiment of the invention, also shown apart from its associated machine frame.

Referring now to FIG. 1, a winning machine W is provided with a pair of concentrically disposed cutter heads 1 and 3 which are fastened to the shafts 2 and 4 respectively, and are rotatably supported by a machine frame (not shown) via the outer bearings 5 and inner bearings 6. The shaft 2 is disposed within the hollow shaft 4 and is guided therein by the bearings 6. The hollow shaft 4 is guided in the bearings 5 which are supported by the machine frame (not shown), so that the shafts 2 and 4 have a substantially common axis of rotation, fixed in relation to the machine frame and the gear drive mechanism 20. A gear 21 affixed to the shaft 2, and an integrally formed gear 22 disposed externally on the shaft 4 are provided for rotatable driving the cutter heads 1 and 3 respectively.

The gear drive mechanism 20 shafts 23, 24 and 25, any one an input shaft. For simplicity, sidered as the input shaft. The though rotatable, are supported fixedly in relation to each other and to the machine frame (not shown).

Accordingly, the input shaft 24 is operatively connected to be rotated by a prime mover (not shown) and is provided with three of which can be used as the shaft 24 shall be conshafts 23, 24 and 25, al-

transmits its rotary motion to the shafts 23 and 25 via the gears 7 and 9 respectively, which mesh with the gear 8 affixed to said shaft 24.

As shown in FIG. 1, the gear drive mechanism is shown in one particular gearing configuration (i.e., gears 7, 8 and 9 in mesh). In addition to the set of transmission ratios provided between shafts 23 and 25 and input shaft 24, by the gears 7, 8, and 9, another set of transmission ratios is provided by the gears 10, 11 and 12, which are also aflixed to the shafts 23, 24 and 15 respectively. Either of these two sets of transmission ratios can be selected as desired or required to establish a particular winning reaction condition by means of the gear shifter 14, which is operated by conventional means (not shown). If desired additional gears (not shown) can be provided on the shafts 23, 24 and 25 to increase the number of transmission ratio sets which are available.

Since it is necessary for the cutter heads 1 and 3 to rotate in opposite directions in order for their reactions to be counterbalanced to any extent, an idler gear 26 is interposed in the power transmission path from shaft 23 to shaft 2, as between the gear 15 afiixed to shaft 23 and gear 21, with the shaft 4 being driven directly by shaft 25 via gear 27 affixed thereto and gear 22.

If desired, the idler gear 26 can be interposed between gears 22 and 27, (i.e., in the power transmission path from shaft 25 to shaft 4), instead of between gears 15 and 21 as shown.

In the operation of the winning machine W rotary power from the prime mover (not shown) is applied to the input shaft 24 and is divided into two paths, one to the cutter head 1 via the train of gears 8, 7, 15', 26 and 21, and the other to the counter-rotating cutter head 3 via the train of gears 8, 9, 27, and 22. Since the mechanical power input to shaft 24 must necessarily equal the sum of the mechanical power delivered to each cutter head 1 and 3 (less any intervening losses, by friction etc.) and the power delivered to each cutter head 1 and 3 is directly related to its associated torque and peripheral speed, there is a fixed relation between the torques and angular velocities of the cutter heads 1 and 3 and the shaft 24.

In the case of an ideal lossless power transmission through the mechanism 20, this relation can be expressed by the formula:

where T T and T are the torques transmitted in the cutter heads 1 and 3 and in the shaft 24 respectively, and W1, W3 and W24 are the respective angular velocities of said cutter heads 1, 3 and shaft 24.

Since in the apparatus W of FIG. 1 the angular velocities W1, W3 and W24 are related by the transmission ratios of the gearing between shafts, 2, 4 and 24, with one of these transmission ratios being negative due to the counterrotation feature, it is apparent that torque applied to each cutter head 1 and 3 can be controlled by applying an appropriate torquet to the shaft 24 and selecting an appropriate set of gears such as the gear sets 7, 8, 9, or 10, 11, 12 or similar set (not shown). Similarly, by driving the shaft 24 at an appropriate speed, a given combination of cutter head 1 and 3 peripheral speeds can be obtained.

In the operation of the winning machine W reaction forces and moments will be imposed on the cutter heads 1 and 3 at those cutters 28 which engage the mineral deposit. Generally, the direction of the reaction forces will vary with the portions of the cutter heads 1 and 3 having cutters 28 in mineral-winning engagement. By operating said cutter heads 1 and 3 at appropriate peripheral speeds and torques as aforesaid, these reaction forces and their moments can be utilized to guide the winning machine W in a desired direction. Such guidance can be obtained by an operator (not shown) observing the progress of the mineral-winning machine and manipulating the gear shifter 14 and prime mover (not shown) output so as to cause the cutter heads 1 and 3 to progress in a desired direction. Aso, if desired, such guidance can be obtained automatically through the use of a conventional control system (not shown) in lieu of an operator.

In the embodiment of the invention shown by FIG. 2, the gear drive mechanism 20 is substantially replaced by independent drives 13 which can each include a prime mover such as a motor, or be operatively connected to be driven by individual prime movers.

The drives 13 are variable speed drives such as, for example, a DC. motor, or a combined motor and variable speed transmission, so that the cutter heads 1 and 3 can be operated at such speeds as are required for the purposes of the invention.

As is apparent, the winning machine W of FIG. 2 is generally preferable to the winning machine W of FIG. 1, in that it is not necessary to provide a multitude of shiftable gear sets to cover a given range of cutter head 1 and 3 speeds. Also, as distinguished from the gear drive mechanism 20, the variable speed drives 13 are each capable of covering a continuous speed range, such as, for example, where the drives 13 include DC. motors.

As will be obvious to those skilled in the art upon reading the foregoing description, the winning machine of the instant invention is not necessarily limited to the use of two concentric counter-rotating cutter heads, as illustrated by way of example in FIGS. 1 and 2, but may be provided with additional cutter heads which can either be mounted concentrically, or in spaced relation to each other, or even with their rotation axes angularly inclined with respect to each other.

What is claimed is:

1. A winning machine comprising a machine frame, a pair of concentrically rotatable cutter heads supported by said machine frame, a variable transmission ratio gear drive having an input shaft connectable to a prime mover for rotation thereby, a pair of output shafts each connected to a corresponding cutter head to transmit rotary power thereto from said input shaft to counterrotate said cutter heads, and gear ratio change means operable to vary the rotation speeds of said cutter heads to maintain a selected rotary speed ratio between said cutter heads to correspondingly regulate the net reaction force and moment transmitted to the machine frame through said cutter heads.

2. The winning machine according to claim 1 wherein said gear ratio change means includes a plurality of selectively intermeshable gear sets, each gear set including three gears, one mounted on said input shaft and one mounted on each output shaft, each gear set corresponding to a characteristic cutter head speed ratio.

3. The winning machine according to claim 1 wherein said cutter heads, input shaft and both output shafts are disposed for rotation about mutually parallel axes.

References Cited UNITED STATES PATENTS 433,610 8/1890 Bain -91 540,306 6/1895 Fry 175-106 X 2,699,328 1/1955 Alspaugh et al 29960 X 2,798,707 7/1957 Kandle 29960 X 2,973,949 3/1961 Densmore 29960 X 3,195,661 7/1965 Jackson et al. 17595 ERNEST R. PURSER, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent NO. 3,322,466 May 30, 1967 Werner Mennekes It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 17, for "I the operation" read In the operation line 48, for "are" read art column 2, line 63, for "rotatable" read rotatably column 3, line 10, for "15" read 25 line 59, for "torquet" read torque Signed and sealed this 9th day of January 1968.

(SEAL) Attest:

Edward M. Fletcher, Jr. EDWARD J. BRENNER Attesting Officer Commissioner of Patents

Claims (1)

1. A WINNING MACHINE COMPRISING A MACHINE FRAME, A PAIR OF CONCENTRICALLY ROTATABLE CUTTER HEADS SUPPORTED BY SAID MACHINE FRAME, A VARIABLE TRNSMISSION RATIO GEAR DRIVE HAVING AN INPUT SHAFT CONNECTABLE TO A PRIME MOVER FOR ROTATION THEREBY, A PAIR OF OUTPUT SHAFTS EACH CONNECTED TO A CORRESPONDING CUTTER HEAD TO TRANSMIT ROTARY POWER THERETO FROM SAID INPUT SHAFT TO COUNTERROTATE SAID CUTTER HEADS, AND GEAR RATIO CHANGE MEANS OPERABLE TO VARY THE ROTATION SPEEDS OF SAID CUTTER HEADS TO MAINTAIN A SELECTED ROTARY SPEED RATIO BETWEEN SAID CUTTER HEADS TO CORRESPONDINGLY RGULATE THE NET REACTION FORCE AND MOMENT TRANSMITTED TO THE MACHINE FRAME THROUGH SAID CUTTER HEADS.

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