RU2085294C1 - Concentration table - Google Patents

Abstract

FIELD: gravity concentration in integrated mining and concentration enterprises and in laboratories. SUBSTANCE: concentration table has deck mounted on frame with the aid of flexible supports, feeder placed over the deck, arrangement for unloading the concentration products, vibrator containing armature and DC winding secured on immovable core, and vibrator control unit. The table is provided with sealed housing for the vibrator and with rigid connecting rod with two spherical pairs. The winding consists of two sections and the core has an air gap situated between the winding sections. The housing is secured on the frame and the core is fastened immovably in the housing. The armature is adapted to move into and out of the air gap. The armature is connected with the deck by means of the connecting rod having two spherical pairs. The arrangement for removing products of concentration is positioned under the unloading edge of the deck. EFFECT: improved efficiency. 5 cl, 7 dwg

Description

 The invention relates to mechanical engineering, namely to processing equipment, and can be used at mining plants and in laboratory conditions as devices for gravity ore beneficiation with the optimal law of motion.

 Famous concentration table (Rudin VA. Concentration table. Aut. St. USSR N 1076142, class B 03 V 5/06, B 03 B 1/16, publ. 28.02.84, Bull. N 8), including decks mounted on ropes on a fixed frame, a drive consisting of low-speed unbalance shafts and high-speed unbalance rigidly fixed to the shaft, and a drive connecting device with decks made in the form of an articulated rod. Slow-speed and high-speed unbalances of the drive are installed on one shaft, while the low-speed unbalance is mounted on the shaft with the possibility of relative rotation.

 The specified concentration table does not allow you to adjust the kinematic characteristics of the deck without stopping the process, partial dismantling of the vibration exciter, replacing unbalances and changing the phase angle of high-speed unbalances. In addition, the drive of the concentration table implements only the biharmonic law of motion, and the presence of a mechanism for converting the rotational motion of the rotor of the electric motor into reciprocating motion of the deck reduces reliability and increases the mass of its moving parts, which, in turn, requires a more powerful drive.

Also known is a concentration table (Barzukov O.P. Vaysberg L.A. Concentration table. Automat. St. USSR N 638371, class B 03 B 5/04, publ. 25.12.78, Bull. N 47), containing a deck, mounted on elastic elements, a feeder, a device for removing concentrate and a single-frequency unbalanced vibration exciter. The total stiffness of the elastic elements in the direction of oscillation is associated with the frequency of rotation of the pathogen and the mass of the table with the ratio C = 4ω ² m
The specified concentration table does not allow you to adjust the kinematic characteristics of the deck without stopping the process, partial dismantling of the vibration exciter, replacing unbalances and changing the stiffness of the elastic elements. In addition, the drive of the concentration table implements only the biharmonic law of motion, and the presence of a mechanism for converting the rotational motion of the rotor of the electric motor into reciprocating motion of the deck reduces reliability and increases the mass of its moving parts, which, in turn, requires a more powerful drive. A change in the pulp mass on the table during operation leads to a deviation from the indicated ratio, which affects the productivity and quality of the enrichment process.

 Famous laboratory concentration table (Rudin V.A. Laboratory concentration table. Autost. St. USSR N 1417929, class B 03 B 5/04, 5/06, publ. 23.08.88. Bull. N 31), including a deck, bearings and drive, eccentric low-speed and high-speed mechanisms with driven links located in the table supports and parallel to each other, mounted in bearings on the driven link of the high-speed mechanism, low-speed and high-speed shafts, interconnected by a gear transmission and a compensating clutch. Moreover, the low-speed and high-speed mechanisms are made sinus, their driven links with one degree of freedom, and the deck is rigidly connected with the driven link of the slow-moving mechanism.

 The specified concentration table implements only the biharmonic law of motion. The presence of a complex motion conversion mechanism with a long kinematic chain and a large number of kinematic pairs increases the cost and mass of the moving parts of the laboratory concentration table, reduces its reliability and durability, which limits the scope.

 Known round concentration table (Rudin A.D. Rudin V.A. Round concentration table. Aut. St. USSR N 1602572, class B 03 B 5/04, publ. 10.30.90 in Bull. N 40), which is the prototype of the invention and containing a conical deck mounted on a frame on elastic supports (elements) over which a feeder and a device for removing enrichment products are located. A vibrodriver is installed under the conic deck for creating rotary biharmonic oscillations) made of electromagnets with a common fixed magnetic circuit (core) of stepwise increasing diameter and located coaxially with the deck. Coils with alternating current windings are fixed at each stage of the magnetic circuit, and a coil with direct current winding is fixed at a step of a larger diameter. Anchors with their AC windings are installed coaxially with the magnetic circuit. AC windings are made with different cross sections and the number of ampere turns. Anchors are connected to the deck through elastic elements. The vibrodrive control unit (circuit) includes a phase regulator, a source of direct and alternating current, and allows you to adjust the amplitude of each harmonic and the phase angle between them. The deck is made of a movable plate, a conical frame of corners and shaped iron, on top of which a cone of sheet metal with a rubber coating with flutes is installed.

 The specified round concentration table has a number of significant disadvantages. The presence of movable windings leads to a decrease in the durability of the table, since they are susceptible to vibration, under the influence of which their compound is crumbled and their connection with the control unit is destroyed. Due to the fastening of a movable plate with elastic elements, movable windings and their anchors on the deck, the mass of the moving parts increases, and the elastic elements in the motion transmission chain from the movable windings to the deck reduce the amplitude of its vibrations. The last two shortcomings lead to the fact that it is necessary to increase the power of the vibroconductor, which increases the power consumed from the network. The vibratory drive of the round concentration table implements only biharmonic vibrations, which does not allow to optimize the deck motion law, and, therefore, to achieve the highest quality and enrichment performance.

 The invention is aimed at increasing the durability of the table, facilitating moving masses, reducing power consumption, improving the quality and productivity of the enrichment process.

 This effect is achieved by the fact that in a known concentration table containing a deck mounted on a frame on elastic supports, above which there is a feeder, a device for removing enrichment products, a vibro drive containing a DC winding mounted on a fixed magnetic circuit and an armature, a vibro drive control unit, characterized the fact that a sealed vibrodrive housing and a rigid connecting rod with two spherical pairs are introduced into it, and the winding is made of two sections, the magnetic circuit is made with one air by the azor located between the winding sections, the housing is fixed on the frame, the magnetic circuit is fixed in the housing immovably, and the armature is movable with the possibility of fully entering and leaving the gap, in addition, the armature is connected to the deck by a connecting rod with two spherical pairs, and a device for removing products enrichment is located under the discharge edge of the deck.

 An additional two-section DC winding and an additional armature can be introduced into it, and the magnetic circuit is equipped with an additional air gap located between the sections of the additional winding, the additional armature is movably mounted in the housing with the possibility of full entry into and exit from the additional gap, in addition, both anchors rigidly interconnected in such a way that when one anchor enters completely into its air gap, the other anchor completely leaves its air gap.

 The deck can be made of two thin sheets with a rigid frame, chemically resistant rubber with flutes is fixed on the top sheet, and the gap between the sheets is filled with a light and durable honeycomb filler.

 A buffer fixedly mounted between winding sections can be introduced into it.

 Two buffers can be introduced into it, one of which is fixedly installed between sections of one winding, and the other between sections of another winding.

 In FIG. 1 shows a proposed concentration table, side view; in FIG. 2 vibrodrive with two two-section windings; in FIG. 3 is a view of FIG. 2 on top; in FIG. 4 functional diagram of the control unit; in FIG. 5 - deck concentration table, bottom view; in FIG. 6 deck in a cut; in FIG. 7 view of the deck from above.

 The concentration table (FIG. 1) contains a frame 1 with a vibrodrive 2 fixed on it and a deck 3 mounted on the frame 1 by means of elastic supports 4 made in the form of plates. Feeder 5 is installed above deck 3, and a fixture 6 for removing enrichment products is placed under the discharge edge of the deck. The vibrator 2 consists of a housing 7 fixed to the frame (Fig. 2), in which by means of the covers 8 and 9 the magnetic circuit 10 is fixedly fixed with an air gap 11; DC winding 12, divided into two sections, mounted on the magnetic circuit 10 on both sides of the air gap 11; anchors 13 installed in the housing 7 in the frame of the guides 14 coaxially with the air gap 11; the rod 15, which is fixedly mounted on the frame of the guides 14 and passes through the hole in the cover 8. The tightness of the cover 8 is provided by the corrugation 16. The vibrodrive 2 is connected by the rod 15 to the deck 3 (figure 1) through the connecting rod 17 with two spherical pairs.

 The concentration table control unit (Fig. 3) may include a power supply unit 18, a zero-pulse generator 19, a pulse counter 20, a switch 21, an adjustable delay unit 22, an “I” logic block 23, a pulse power amplifier 24, and a thyristor power unit 25. The control unit is connected to the winding 12 (figure 2) of the vibrator (figure 1).

 The control unit can also be performed according to known schemes (ed. St. USSR N 9519621. The control method of the thyristor trigger. Publ. In BI. N 26, 1984).

 The vibrodrive 2 (Fig. 1) of the concentration table, made according to claim 2, contains an additional two-section DC winding 26 (Fig. 2), sections of which are mounted on the magnetic circuit 10 on either side of the additional air gap 27, an additional armature 28 installed in the housing 7 on the frame of the guides 14 coaxially with the additional air gap 27 and rigidly connected to the anchor 13 through the frame of the guides 14 so that when one armature enters completely into its air gap, the other armature completely leaves its air shnogo gap. The control unit contains one more identical switch, an adjustable delay unit, an AND logic unit, a pulsed power amplifier, and a power thyristor unit. One of the power thyristor blocks is connected to the winding 13, and the other to the additional winding 26.

 Deck 3 (Fig. 1) of the concentration table, made according to claim 3, consists of its frame 29 (Fig. 4) made of corners and channels, a thin sheet 30, made, for example, of aluminum, is fixedly mounted on the frame 29 which is glued onto the adhesive with a light and strong filler 31, such as polystyrene foam or a thin foil honeycomb. A second thin sheet 32 is laid on a flat surface of the filler, onto which rubber or linoleum with flutes 33 is glued. On both sides of the deck there are boards 34 to limit the front of the water drain.

 The vibration drive 2 of the concentration table, made according to claim 1, contains a buffer 35, motionlessly mounted between the sections of the winding 12.

 The vibratory drive 2 of the concentration table, made according to claim 1, contains a buffer 35, fixedly mounted between sections of the winding 12, and a buffer 36, fixedly installed between sections of the additional winding 26.

 The concentration table (figure 1) works as follows.

 In the initial position, deck 3 is at the beginning of the forward stroke (extreme left position), while the anchor 13 (figure 2) is completely removed from the air gap 11.

 When you turn on the power supply 18 (Fig. 3), the zero-pulse generator 19 is started, which produces short pulses at the moments when the voltage of the mains voltage passes through zero, therefore, their repetition rate is 100 Hz. They are fed to the input of the pulse counter 20 and to the input of the adjustable delay unit 22. The pulse counter calculates the number of zero pulses from the beginning of the cycle and gives its value in the position code to the switch 21, which generates one strobe pulse per cycle of the concentration table. The duration of the strobe pulse, its position relative to the beginning of the cycle and the duration of the cycle are set by the number of zero pulses, and, therefore, they are a multiple of 0.01 s. The pulses from the switch 21 are fed to one of the inputs of the logic block “And” 23 and gate the passage of the zero pulses delayed in the adjustable delay unit 22. The delay value can smoothly vary within half the period of the mains frequency (0.01 s). The past packs of null pulses are transferred to a pulse power amplifier 24 and then to the power thyristor unit 25. The pulse power amplifier 24 generates pulses synchronous with zero pulses and whose power is sufficient to open the thyristors of the power thyristor unit 25. The power thyristor unit 25 smoothly regulates the amplitude of the voltage of the mains, rectifies it and connects the winding 12 (Fig. 2) of the vibrator 2 (Fig. 1) to the mains when a packet of zero pulses is supplied to it.

 The control unit generates voltage pulses for the winding 12 (figure 2), modulated by half-waves of the mains voltage, and makes it possible to change: the duration of the cycle of the table, the position of the beginning of the voltage pulse relative to the beginning of the cycle, the half-wave amplitude, the phase opening angle of each half-wave, the number of half-waves in each pulse, thus changing the duration of the voltage pulse supplied to the winding 12.

 When a voltage pulse is applied to the winding 12, a current arises in it, resulting in a magnetic flux, which, closing through the magnetic circuit 10, the air gap 11 and the armature 13, creates an electromagnetic force that draws the armature 13 into the gap 11. At the same time, the armature 13 through the frame of the guides 14, the rod 15 and the connecting rod 17 (Fig. 1) pushes the deck 3 to the right, which, moving, deforms the elastic supports 4. The magnitude of the electromagnetic force acting on the armature 13 (Fig. 2), depends on its position, the inductance of the winding and the magnitude of the current in it, which, in its essay whether it depends on the magnitude, shape and duration of the voltage pulse. The increase in voltage and its duration leads to an increase in electromagnetic traction, and, consequently, to an increase in the acceleration of deck 3 (Fig. 1). Until the armature 13 (Fig. 2) fully enters the gap 11, the supply voltage is removed from the winding 12, after which it is shunted by itself, and the deck is braked by the elastic supports 4 (Fig. 1) and reaches the end of the working stroke (extreme right position) . The reverse stroke of the deck 3 and the anchor 13 (figure 2) (movement from right to left) begins under the action of the elastic forces of the supports 4 (figure 1). The potential energy of the supports 4 is spent on useful work and on increasing the kinetic energy of the deck. After the deck passes through the position of elastic equilibrium, the supports 4 again begin to slow down the deck and it reaches the end of the reverse stroke (extreme left position), ending the cycle of the concentration table).

 Increasing the durability of the table is due to the exclusion of moving windings subject to vibration, due to which their compound quickly crumbles and their connection with the control unit is destroyed.

 The facilitation of moving masses is due to the replacement of anchors with alternating current windings by one armature. In addition, in the prototype, the anchors are connected to the deck by means of elastic elements, which leads to a decrease in the amplitude of the deck vibration compared to the amplitude of the anchors. In this case, the amplitude of the deck oscillations can be increased either by increasing the mass of the anchors with their windings, or by increasing the amplitude of the oscillations of the anchors. This leads either to an increase in moving masses, or to an accelerated destruction of the windings and elastic elements.

 The facilitation of moving masses leads to a decrease in the power required for their oscillation, and, consequently, to a reduction in power consumption.

The proposed concentration table provides the following possibilities for varying its kinematics:
a) A change in the duration of the cycle leads to a change in the frequency of the disturbing force. A simple control unit allows you to change the disturbance frequency from 50 Hz to 1.5625 Hz, which corresponds to 3,000 93.75 double deck moves per minute.

 b) Changing the duration of voltage pulses and the amplitude of their half-waves leads to a change in the shape and magnitude of the traction force of the electromagnet, and, consequently, to a change in the amplitude of the oscillations, and to a change in the acceleration rate of the deck.

 c) A change in the opening angle of the thyristor leads, firstly, to a change in the effective voltage of the pulse, which is equivalent to adjustment according to item b), and secondly, a change in the shape of the modeling voltage, which leads to a change in the shape of the current in the winding, which affects the shape characteristics of the electromagnetic force of excitation of the vibration exciter. This allows you to adjust the amplitude of the oscillations with a frequency of 100 Hz, and to superimpose these oscillations on the main oscillations of the concentration table at the time of applying voltage pulses.

 Each of the listed parameters in p.p. a) c) are independently regulated.

Wide possibilities for varying the kinematics of the deck, noted in paragraph a)
c) provide an opportunity to choose any law of the deck movement on the reverse stroke, which helps to improve the quality and productivity of the enrichment process.

 The concentration table according to claim 2 (Fig. 1) works as follows. In the initial position, deck 3 is at the beginning of the forward stroke, while the anchor 13 (FIG. 2) is completely withdrawn from the air gap 11, and the additional anchor 28 is fully inserted into the additional air gap 27.

 When you turn on the power supply 18 (figure 3) of the control unit, it starts the zero-pulse generator 19, which generates short pulses at the moment the voltage of the mains voltage passes through zero. Their repetition rate is 100 Hz. They are fed to the pulse counter 20 and to two identical adjustable delay units 22. The pulse counter 20 counts the number of zero pulses from the beginning of the cycle and provides this value in the position code to two identical switches 21, each of which generates one strobe pulse per cycle concentration table work. The duration of each strobe pulse, its position relative to the beginning of the cycle and the duration of the cycle are set by the number of zero pulses, and, therefore, they are a multiple of 0.01 s. The pulses from each switch 21 are fed to one of the inputs of the corresponding logical block “AND” 23 and gate the passage of zero pulses delayed in the corresponding block of adjustable delay 22. The delay value can smoothly vary within half the period of the mains frequency (0.01 s) on each channel independently. The past packs of zero pulses fall on two identical pulse power amplifiers 24, and, further, on two identical power thyristor units 25. Each pulse power amplifier 24 generates pulses synchronous with its zero pulses and whose power is sufficient to open the thyristors of their power thyristor block 25. Each power thyristor block 25 independently of each other smoothly regulates the amplitude of the voltage, rectifies it and connects its winding of the vibrator 2 (Fig. 1) to the mains in supplying time it packs zero pulses (one connects a winding 12 (Figure 2) and the other connects the secondary winding 26).

 The control unit generates voltage pulses for winding 12 (Fig. 2) and additional winding 26, modulated by half-waves of the mains voltage, and makes it possible to independently change for each winding: half-wave amplitude, phase opening angle for each half-wave, number of half-waves in each pulse, position of each pulse relative to the beginning of the cycle, and, therefore, the interval between pulses, and the duration of the cycle.

 When a voltage pulse is applied to the winding 12, a current arises in it, resulting in a magnetic flux, which, closing through the magnetic circuit 10, the air gap 11 and the armature 13, draws the latter into the gap 11. since the armature 13 and the additional armature 28 are rigidly connected between themselves, at the same time, the anchor 28 leaves the additional air gap 27, in addition, the anchor 13 through the frame of the guides 14, the rod 15 and the connecting rod 17 (figure 1) pushes the deck 3 to the right, which, moving, deforms the elastic supports 4. The magnitude of the electromagnetic force acting in this case armature 13 (Figure 2), depending on its position, the inductance coil 12 and magnitude of the current therein, which in turn depends on voltage and duration of the voltage pulse. The increase in voltage and the time of its action leads to an increase in electromagnetic traction, and, consequently, to an increase in the acceleration of deck 3 (Fig. 1). Until the anchor 13 (FIG. 2) fully enters the gap 11, the supply voltage is removed from the winding 12, after which it shunts by itself, and the deck 3 (FIG. 1) is braked by the elastic supports 4, reaching the end of the forward stroke. After the reverse stroke of the deck 3 starts, a voltage pulse is applied to the additional winding 26 (Fig. 2), as a result of which, an electromagnetic arm begins to act on the additional armature 28, it is drawn into the additional gap 27 and pushes the armature 13 out of the gap 11, in addition, the anchor 28 through the guide frame 14, the rod 15 and the connecting rod 17 (Fig. 1) pulls the deck 3 to the left, which, while moving, deforms the elastic supports 4. Until the anchor 28 (Fig. 2) fully enters the gap 27, it is removed from the additional winding 26 supply voltage, after which it is shunted by itself, and deck 3 (figure 1) is braked by elastic supports 4, reaching the end of the reverse stroke and ending the cycle of the concentration table.

 The control unit carries out adjustments a) c) regardless of winding 12 and additional winding 26. This allows you to create any laws for the motion of the deck both during the forward stroke and during the reverse stroke, which contributes to better separation and enrichment of the concentrate, the accelerated movement of particles to the discharge the end of the deck, thereby increasing the quality and productivity of the enrichment process.

 When performing the concentration table according to claim 3, its operation does not change.

 The facilitation of the mass of the moving parts occurs as a result of the 5% lightening of the deck, which is achieved by eliminating the movable plate, replacing the conical frame from the corners and the profile iron with a sheet metal cone by a flat frame and two thin sheets with a light and durable honeycomb core.

 The facilitation of moving masses leads to a decrease in the power required for their oscillation, and, consequently, to a reduction in power consumption.

 When performing the concentration table according to claim 4, the direct course of deck 3 (phys. 1) is limited by buffer 35 (Fig. 2). At the end of the forward stroke, the anchor 13 hits the buffer 35, transmitting a large negative acceleration to deck 3 (Fig. 1). The strength of the impact, and therefore the acceleration of the deck 3, depends on the position of the buffer 35, the stiffness of the supports 4 and the buffer 35, on the operation of the electromagnetic traction force during its operation.

 High acceleration of the deck provides accelerated movement of the product to the discharge end of the deck, thereby increasing the efficiency of the enrichment process.

 When performing the concentration table according to claim 5, the direct course of deck 3 (FIG. 1) is limited by buffer 35 (FIG. 2). At the end of the forward stroke, the anchor 13 hits the buffer 35, transmitting a large negative acceleration to deck 3. The impact force, and therefore the magnitude of the acceleration, depends on the position of the buffer 35, the rigidity of the supports 4 and the buffer 35, on the operation of the electromagnetic traction force during the direct move.

 The buffer 36 (Fig. 2) limits the reverse stroke of deck 3 (Fig. 1). At the end of the return stroke, an additional anchor 28 hits the buffer 36, transmitting a large positive acceleration to deck 3. The impact force depends on the position of the buffer 36, the stiffness of the supports 4 and the buffer 36, and the electromagnetic traction during the return stroke.

 Large accelerations of the deck at the end of the forward and reverse moves due to a hit on the buffer increase the concentrate movement along the table deck and improve the separation of ore into fractions, increasing the quality and productivity of the beneficiation process.

Claims (5)

 1. A concentration table containing a deck mounted on a frame on elastic supports, above which a feeder, a device for removing enrichment products, a vibro drive containing a DC winding mounted on a fixed magnetic circuit, an anchor, a vibro-conductor control unit, characterized in that a sealed vibrodrive housing and a rigid connecting rod with two spherical pairs, moreover, the winding is made of two sections, the magnetic circuit is made with one air gap located between the winding sections, pus fixed to the frame, a magnetic circuit supported in the housing fixedly and adjustably anchored with full entry into the gap and an exit from it and connected to the deck anchor rod with two spherical pairs, and a device for enrichment detachably disposed below the product discharge edge of the deck.  2. The table according to claim 1, characterized in that an additional two-section DC winding and an additional armature are introduced into it, and the magnetic circuit is equipped with an additional air gap located between the sections of the additional winding, the additional armature is movably mounted in the housing with the possibility of full entry into the additional gap and leaving it, both anchors are rigidly interconnected in such a way that when one anchor enters completely into its air gap, the other anchor completely leaves its air gap.  3. The table according to claim 1, characterized in that the deck is made of two thin sheets with a rigid frame, chemically resistant rubber with corrugations is fixed on the top sheet, and the gap between the sheets is filled with a light and durable honeycomb filler.  4. The table according to claim 1, characterized in that a buffer is inserted into it, fixedly mounted between the winding sections.  5. The table according to claim 2, characterized in that two buffers are inserted into it, one of which is fixedly installed between sections of one winding, and the other between sections of another winding.

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