CS204965B2 - Rotary cutter for the mining machine for the mineral extraction - Google Patents

Abstract

1,219,159. Mineral-mining cutter means. COAL INDUSTRY (PATENTS) Ltd. 1 Aug., 1969 [6 Aug., 1968], No. 37466/68. Addition to 1,088,845. Heading E1F. Behind a cutter tool 28 of fixedly mounted cutter tools of a rotary cutter head of a mineral-mining machine a further cutter tool 26 is so resiliently mounted on the head that the penetration of this tool over at least a substantial part of its cutting path is shallow and constant and any resultant relative movement between this cutter tool 26 and the cutter tool 28 on the tool 26 encountering a change in the mineral in which it is cutting causes means associated with the tool 26 to give a signal indicative of said movement. The tools 26, 28 may be the same or the tool 28 may be wider than the tool 26, which may project in the direction of its length beyond the tool 28. The rotary head may be a disc, a drum or a trepanning type head. The two tools 26, 28 may be mounted in separate boxes or in a common box mountable as a unit on the head. The box associated with the tool 26 houses a transducer, which emits a signal indicative of the relative movement of the tool 26 with respect to it. Means are provided for varying the spacial relationship between the tool 26 and the transducer, which may be an electromagnet. A so constructed rotary cutter head permits of an indication being given of its approach to a boundary layer of the stratum in which it is cutting so that steering adjustments can be made to the machine to keep the head in the stratum.

Description

The present invention relates to rotary milling cutters for mining and quarrying machinery, the milling cutters being equipped so as to be able to obtain data on the edge of the mineral seam in which the machine operates.

It has already been proposed to provide a rotary drill bit with a knife that is mounted movably relative to the mill and associated with a mechanism responsive to the movement of the knife relative to the mill during the working process. To achieve a sufficiently strong indication signal, the knife was mounted on a relatively long flexible beam, the length of which was effectively reduced by a series of stops when the cutting load on the knife exceeded a certain value. However, with this voluminous and complex mechanism, it was not possible to obtain reliable data on the edge of the mineral seam. The reason for this was that incorrect indications occurred as a result of the forces acting on the knife, which were not due to the increased load when the knife encountered a harder mineral.

It was further proposed to determine the edges of the mineral seam in which the mineral extraction machine worked by placing two movably mounted blades directly on the machine body at a certain distance from its rotary cutter. The mechanism associated with each knife provided hydraulic signals that were compared so that when one knife encountered a harder mineral, a change in its signal output was observed relative to the signal output from the other knife, which was still working in a softer mineral.

It has been found that the use of two movably mounted knives does not give a reliable indication of the change in mineral layers. Both blades move relative to the layer only at the speed of the machine body, and the signals were not significant enough to provide the required reliable data on mineral hardness changes.

As the blades moved through the mineral relatively slowly, the shaking of the machine body caused too many incorrect signals. The knives also occasionally broke quite large pieces of mineral from the wall, whereupon the knives were out of contact with the mineral for a short time, resulting in very large signal changes that overlap the required signal changes resulting from the mineral hardness change.

In addition, the indications obtained did not provide seam edge data for the rotary cutter, but instead determined the condition at some distance beyond the rotary cutter.

With the present invention, very clear data on the edge or condition of the mineral seam can be obtained in a manner particularly suited for a mineral mining machine having a rotary cutter, such as a loading and loading machine. The present invention overcomes the drawbacks of earlier designs and allows an indication to be obtained that can assist the operator of the machine in its proper control. Moreover, the invention makes it possible to obtain a signal which can be used for a control mechanism to adjust the position of the rotary cutter relative to the mineral edge, so that for the first time automatic control of the machine by purely mechanical equipment is possible.

The rotary cutter according to the invention is characterized in that a movably mounted knife is located just behind one of the plurality of knives fixed to the milling cutter and that the movably mounted knife protrudes above the fixed knife in the direction of its length.

This ensures an effectively constant load on the movably mounted blade over the entire cutting path, and therefore a very strong signal can be obtained if the blade encounters a harder mineral, either at the seed or ceiling edge, or alternatively, encounters a harder mineral minerals forming a relatively thin tang, located between the upper and lower edges of the mineral seam.

The invention allows the use of a relatively high operating speed of a blade movably mounted on a rotary cutter so that a sufficiently strong one is achieved. signal, the signal change when encountering a harder mineral is not obscured by incorrect signals.

In addition, the invention allows the movable knife to be mounted on a relatively short beam of simple construction and does not require clips or other complications to shorten the effective length. Thus, the knife seating is very compact and robust to facilitate its assembly in the case of a rotary cutter, which may be a disc or drum of a loading and loading machine or a milling head of a punching machine.

The invention is illustrated by way of example in the accompanying drawings, in which FIG. 1 is a top view of an end of a loading and loading machine showing a rotary cutter drum, FIG. 2 is a side view of the same end of the machine of FIGS. line III-III of FIG. 1, on an enlarged scale.

The drawings show the invention used on a loading and loading machine 10 that can be moved along the upper flange of an armored coal conveyor 12. The machine has a drum 14, a rotary cutter, which is equipped with a backing plate 16 and helical blades

18.

The drum 14 is provided with fixed milling cutters 20, each of which is housed in a collet 22. The housings 22 are secured to the inside of the backing plate 16 and to the rear sides of the blades 18. The drum rotates in the direction of the arrow in Fig. 2.

The drum 14 is also provided with a movably mounted knife 26 located immediately behind the fixed knife 28 and projecting in the direction of its length over the fixed knife 28.

Length increase over. a fixed knife 28 in the radial direction is shown in FIG.

The blades 26 and 28 are arranged in an assembly 30 supported on a support plate 16.

Giant. 3 aligns the assembly 30 more subtly. It consists of a support part 32, to which the housing 22 for the knife 28 is welded and in which the transverse recess 34 is located. The recess 34 has a housing 36 for the knife 26, the housing 36 secured by screws 38 to the upper end of the short bracket beam 40 The lower end of the beam 40 is secured by screws 42 at the bottom of the recess 34. The ends and the upper part of the recess 34 are closed by a U-shaped cover plate 44 held by screws 46. Between the inner edge of the slot 50 in the cover plate 44 and the upper edge of the housing 36 is at 48 'gap (not marked).

The support portion 32 has a cylindrical insert 52 with an aperture 54 for an electromagnetic motion sensor (not shown) connectable by the lead 56 to the control circuit described below. The dirt closure 58 surrounds the inner end of the insert 52 and abuts the side of the housing 36.

The carrier 32 also has a cylindrical plug 60 slidable in the opening of the carrier; the plug abuts the sleeve 36 and is supported by the rubber member 62 and the cylindrical backing plate 64. The screw 66 adjustable in the support portion 32 engages with its inner end into the backing plate 64 and has a lock nut 68.

The beam 40 is resilient and allows the blade 26 to slide back relative to the support portion 32 and the drum 14 under the cutting load. Such a shift causes inductive changes in the electromagnetic flow in the air gap between the sensor in the aperture 54 and the housing 36, and the sensor produces a corresponding electrical signal for the control circuit.

When the bolt 66 is screwed into the support portion 32, the bracket beam 40 'is subjected to a preload via a rubber member 62 that deforms and acts as a spring to preload the beam 40. This preload makes it possible to vary the effective level of zero force at tilting the knife 26 to accommodate the external electrical circuit. That is, below a certain force acting on the tilting of the blade 26, the beam 40 and the sensor signal in the bore 54 do not deflect.

The assembly 30 is suitably mounted on the support plate 16 and can be removed as a whole for repair or adjustment. The assembly is very compact and robust. The beam 40 is very short. The housings 22, 36 are placed close to each other so that the blades 28, 26 are preferably close to each other.

The tight placement of the knife 26 behind the knife 28 ensures that the knife 26 has a 'truly constant shallow penetration, which exceeds the knife penetration by an' X 'value of 28. The knives on the drum and loading machine drum have a significant variation in

dení zábě; the depth varies from zero at the start of the 180 ° arc, - increases to the maximum at the center of the arc and decreases to zero at the end of the 180 ° arc. This variation would render ineffective every attempt to detect the edges of the seam. However, when the front knife 28 according to the invention with the knife 26 protrudes slightly above the knife 28, a signal indicating changes in the hardness of the mineral with sufficient accuracy for indication or control purposes can be obtained from the sensor.

For example, the size "x" may be 12.7 mm when the maximum blade penetration 28 is 50.8 mm.

In one modification of the apparatus, the fixed knife 26 may be wider than the knife 26. This may be particularly useful if the rotary cutter is a cutter head of the sinking machine.

The inner end of the insert 52 acts as a stop for the housing 36 when the load on the knife 26 is excessive.

The signal from the sensor passes to the reception and indication circuit (not shown), which can be placed in a corridor away from the machine and which converts the signal into any desired form.

This circuit also includes other, not shown, means which align the sensor signal to the angular position of the blade 26 in relation to the axis of rotation of the drum.

14. Other means may include three cam-operated microswitches mounted on the milling head drive shaft. One microswitch is actuated while the blade 26 is cutting, thus allowing the receiving circuit to determine the amplitude of the average signal obtained from the sensor. By comparing the actual signal from the sensor to the average signal, it is possible to determine whether peak signals are occurring. In particular, the invention makes it possible to obtain very distinct signals. If the type of mined coal gives rise to a fluctuating signal, it may be advantageous to compare the actual sensor signal with a signal equal to 1.5 of the normal signal. Even in this case, a very strong peak signal can be achieved.

Claims (7)

SUBJECT A rotary cutter for a mining and quarrying machine having a blade resiliently mounted with respect to the mill and associated with a means responsive to blade movement during cutting, characterized in that the resiliently mounted blade (26J) is located behind one blade (28) in a row milling cutters firmly mounted on and in close proximity to the milling cutter and that the resiliently mounted blade (26) projects over its length over the stationary blade (28). Rotary cutter according to claim 1, characterized in that the resiliently mounted blade (26) is received in a housing (36) carried at one end of a single beam (40). Rotary cutter according to claim 2, characterized in that the fixed blade (28) is mounted in a fixed position Every top - signal, which occurs, - converting circuit to the Schmitt -spoušťovým - - two parallel gate -součinových ^-: units. One of the product gate units is electrically coupled to the other microswitch actuated by the cam associated therewith when the blade 26 cuts at the seam ceiling. The second product gate unit is connected to a third microswitch, which is actuated by a cam associated therewith, ^x when the blade cuts at the seam. Therefore, each-product gate unit has two power inputs which, when properly aligned, causes the signal from the product gate unit to transmit to the indicator circuit. The indicator circuit may comprise two control bulbs, one of which lights up when a signal is transmitted from a product lightyear unit associated with it. As the cutting and loading machine moves along the mineral wall, the cutter head moves to the edge of the coal bed, the knife 26 begins to cut - a different, usually harder material adjacent to the coal bed, sends a signal from the pickup causing the signal to be transmitted into one of the product gate units as described above. This refers to the angular position of the knife 26 and hence the seam edge where the hard mineral is cut, and therefore indicates which control action to use to correct the milling head position. The control operation can be performed manually or automatically, i.e. the signal is transmitted from the product gate unit to the means arranged to control the control mechanism of the cutting machine. In alternative realization other means that respond to the angular position signal of the blade 26 may include a selsyne arrangement or a wiper moving around the impedance bridge. In these embodiments, the sensor signals can be continuously indicated on a circular time base oscilloscope. The housing (22), wherein the knife housings (22, 36) of the blades (28, 26) overlap in their longitudinal direction and are immediately adjacent to each other. Rotary cutter according to Claim 1, 2 or 3, characterized in that it has a pressure plug (60) which abuts the bush (36) with the movably mounted blade (26) and is supported by a spring element (62) whose load is adjustable by a screw (66). Rotary cutter according to any one of the preceding claims, characterized in that the fixed blade (28) and the movably mounted blade (26) are mounted in bushings (22, 36 _t ) housed in a support part (32) which is attachable as a unit for rotary cutter. Rotary cutter according to claim 1, characterized in that the cutter is a drum or disc of the cutting machine and that the pivotally mounted knife (26) is supported on the drum or disc support plate (16) together with a fixed knife (28) which 26) adjacent. A rotary cutter according to claim 1 or 2, characterized in that the width of the pivoting mounted blade (26) is smaller than the width of the adjacent fixed blade (26).