US2429864A - Dry feeding machine having means responsive to weight of material already dischargedfrom automatically movable hoppers - Google Patents

Dry feeding machine having means responsive to weight of material already dischargedfrom automatically movable hoppers Download PDF

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US2429864A
US2429864A US506476A US50647643A US2429864A US 2429864 A US2429864 A US 2429864A US 506476 A US506476 A US 506476A US 50647643 A US50647643 A US 50647643A US 2429864 A US2429864 A US 2429864A
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motor
conveyor
hopper
vibratory
wire
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US506476A
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Grove D Alvord
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Syntron Co
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Syntron Co
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01G—WEIGHING
    • G01G11/00—Apparatus for weighing a continuous stream of material during flow; Conveyor belt weighers
    • G01G11/08—Apparatus for weighing a continuous stream of material during flow; Conveyor belt weighers having means for controlling the rate of feed or discharge

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  • the present invention relates to improvements in dry feeding machines for continuously or intermittently feeding or conveying materials at a controlled or uniform rate, Certain subcombinations herein disclosed have utility apart from the general combination, and are part of the invention.
  • Another object is the provision of a bulk feeding apparatus which may be controlled to prevent flushing of material.
  • Still another object of the invention is to provide a novel control apparatus for controllin an electrical device to secure substantially uniform operation thereof.
  • Another object is the provision of a bulk feeding machine that is of simple construction, is dependable, and which will not tend to hunt.
  • an adjustable electrically controlled vibratory feeder or conveyor unit having a variable impedance in its circuit and which discharges onto a controller having a continuously discharging receiver, and a reversible motor operated by the controller in either direction varies the impedance to control the vibratory feeder and provide a predetermined or substantially constant rate of feed of material to the controller.
  • the control means for the reversible motor preferably null point whereby the reversible motor is supplied with current when the controller is i'erably, the impedance is :al parts, example, a coarse part and e part-(ans.
  • the corn troiler is a scale carrying a uniformly moving endless belt conveyor, and operating overweight and underweight switch means with a null point to control the direction of operation of the reversible motor, and not actuate the reversible motor when the scale is in balance.
  • This control unit including the reversible motor and plural impedances including one or more reserve impedances also has utility apart from dry feeding machines.
  • the apparatus preferably includes an antiflush device to prevent flushing action from the source of supply to the vibratory conveyor, this antifiushing device being controlled by the controller, and its action may be to entirely cut oil? 15 Claims.
  • I (Cl. 222-55) til the supply 'in cases of extreme flushing.
  • the hopper or other source of supply preferably has a vibrator, and when the. supply is cut oil in cases of extreme flushing the action of the hopper vibrator is increased to drive out entrained air from the material.
  • time impulse means is provided to cut off the supply in increments, unless extreme flushing occurs, said means also serving to increase the supply in increments.
  • the supply preferably is controlled by a hopper located adjacent a conveyor trough, and by moving the hopper near or away from the conveyor trough the feed opening therebetween is controlled.
  • Figure l is a side view of a preferred embodiment
  • Figure 2 is an end view of Figure 1
  • FIG. 3 is a side view of the control me'chanism, with parts broken away,
  • Figure l is a plan view of omitted
  • FIGS 5 and 6 are side views of switches
  • Figure '7 is a wiring diagram illustrating operation of a simplified modification
  • Figure 8 is a wiringdiagram illustrating operation of the modification. shown in Figure 1.
  • a frame i which may be constructed of angle iron, and a conical hopper 2 is supported from the frame by cables passing through U- bolts i on the hopper and having their ends se cured to the frame in any suitable manner.
  • the open mouth 6 of the hopper is disposed at an angle to the axis of the hopper and terminates adjacent a conveyor trough 5 having its bottom portions disposed parallel with the open bot-- tom 6 of the hopper and providing a feed open ing therebetween.
  • the conveyor is supported on a base 9 by means of a rear cantilever spring l0 and a front motor l l, and the base 9 is supported from the frame by vibration members 12.
  • the conveyor mounting and mode of operation is substantially-as disclosed and claimed in Patent No. 2,187,717 issued to Carl S. Weyandt, January 13, 1940.
  • a suitable hopper vibrator I3 is mounted on the hopper, this vibrator preferably being Figure 3, with part the limit constructed and operated as disclosed in said patent. It will be seen that the hopper may be pivoted about its supporting cables 3 to bring the open edge or mouth 6 into close or substantial coincidence with the bottom I of the vibratory conveyor trough to shut oi! the feed from the hopper, or the feed from the hopper may be reduced or increased as desired by varying or ad- Justing the feed opening between bottom 3 and the hopper mouth 3. The hopper and conveyor thus cooperate to form a valve.
  • An arm I5 is pivoted to the side of the hopper in any suitable manner, and a crank II linked thereto is mounted to rotate with a shaft I1.
  • An indicator arm I3 cooperating with a scale I3 shows the position of the hopper.
  • a motor 20, preferably of the torque type. is provided to rotate shaft II through gears or the like to position the hopper and thus control the feed opening.
  • the hopper may be positioned manually.
  • a second frame 2I- which may be made integral with the frame I, is located adjacent thereto and supports a scale designated generally at 22.
  • This scale may be of any suitable type or construction and as shown has a load pan or platform 23, and counterpoise arms 24 and 25 carrying counterpoises 26 and 21.
  • Two pairs of straps 23 and 29 are secured to the platform 23 in any suitable manner and carry a conveyor frame 3
  • Guard plates 35 are provided to prevent material spilling over the sides.
  • a constant speed motor 36 which may be of the synchronous type, is suitably secured to the frame 2
  • the swinging mo ement of the conveyor frame is limited by a torque bar which is not here shown and is disclosed and claimed in the application of Carl S. Weyandt Serial No. 362,500, filed October 24, 1940, now Patent No. 2,340,030, dated January 25, 1944, for Weighing conveyor.
  • a brush 44 is suitably secured to the conveyor frame for wiping the belt.
  • housing 45 and 45 on the frame of the scale are switch contacts of suitable construction, as for example, vacuum enclosed contacts for controlling the weighing action, and in housing 41 are antifiushing switches to control flushing from the hopper.
  • the weight controlling mechanism first will be described.
  • a suitable control housing (not shown) which preferably is apart from the scale, is a base member 5
  • a manually operated rheostat 50 is provided in the circuit of motor 52.
  • a shaft 55 is suitably journalled in the'frame and is driven by worm 53 engaging worm wheel 56thereon.
  • At one end shaft 55 carries a pinion 5'! meshing with a spur gear 58 mounted on a shaft 59 which carries a contact arm 6
  • One terminal of the rheostat is provided at 33v and a contact member 64 electrically connected to the contact arm BI has a terminal 65.
  • the rheostat coil has a second terminal 66 which is suitably connected to terminal 65.
  • Shaft 55 carries a second pinion 38 at its other end which meshes with a spur gear 39 journalled for rotation on stub shaft II, and a hub I0 on gear 69 has a screw 12 or other projection.
  • is suitably coupled to a shaft II which carries a contact arm 14 about a coiled wire coarse rheostat II, and a pin 13 extends from shaft 1
  • gear 03 may be rotated through almost from one extreme to the other before screw I2 engages pin It to move contact I4 of the coarse rheostat.
  • Limit switches enclosed in boxes I1 and ll of suitable construction ar provided to stop operation of motor 52 and may be employed to actuate an alarm.
  • -'Ihe mechanism for switch 11 comprises a push rod 3
  • Arm 32 has an extension 31 adapted to extend into the path of an actuating pin 33 on gear 53 by which the-arm is depressed to cause pusher 35 to move push rod 3
  • Limit switch I3 has a push rod 9
  • a pin 35 limits downward motion of arm 32.
  • Arm 32 has a similar extension 31 adapted to extend into the path of an actuating pin 33 on gear 53 by which the arm 32 is elevated to cause pusher to move push rod 3
  • the pin 13 will normally be approximately 180 from screw I2.
  • on shaft 53 is rotated through worm 53, worm wheel 53, shaft 55, pinion 51, and spur gear 53 on shaft 53 to increase the resistance in the vibratory conveyor circuit thus reducing the amplitude of vibration of the vibratory conveyor I to reduce the amount of material being fed therefrom onto the belt conveyor 34.
  • the underweight switch is actuated to cause the direction of motor 52 to be reversed to cause first a reverse rotation of vernier rheostat arm 5
  • 0I and I02 have the usual anodes I03 and I04 and cathodes I05 and I05 and a transformer I01 to provide-a heating current from the mains I03 and I03 of an alternating current source. It will be understood that any suitable type of rectifier may be provided in place of the vacuum tube rectifiers, such as dry disk, electrolytic or the like.
  • the belt conveyor motor 36 is connected to mains I08 and I09 through a suitable switch.
  • the hopper vibrator motor I3 is actuated by the current impulses supplied through tube IOI and which are regulated by the manual operated rheostat I I0, and the circuit is completed through wire III and load switch H6.
  • the vibratory conveyor motor II is actuated by the spaced current impulses supplied through tube I02, ammeter H2 and which are regulated by the manually operated rheostat H3, when the switch H4 is in the upward position shown for manual operation, the circuit being completed through wire I I I.
  • the automatic weighin control reversible motor 52 is connected to the power line I08 through a lead wire H5, switch H4, lead wire III, manual rheostat 50 and lead wire II 8 to a motor terminal H9, and assuming limit switch I! closed as shown, terminal I20 is con- I nected by switch I! to limit switch terminal I29, and by wires I28 to scale controlled contact I24.
  • the scale control switch has a movable contact arm I2I operated by the scale and connected by lead wire I23 and common return wire III to the main I09. Contact I connects by lead wire I26 to a terminal I21 0f the limit switch I9, and a condenser I3I is supplied between the limit switches to reduce arcing and prevent passage of direct current impulses simultaneously through both switches.
  • the current impulses for the conveyor motor II passthrcugh tube I02, manual rheostat H3 and through motor operated rheostats 62 and 15 to the vibratory conveyor motor II, and by wire III to main I09.
  • the motor 52 which controls the rheostats 62 and I5 is in shunt with the circuit of the vibra-- tory conveyor motor, and what may be called the scale underlcad control circuit extends from main I09 through wires HI, I23, switch contacts I2I, I24, wire I28, switch 11, motor terminals I20, H9, wire H8, rheostat 50, wire HI, switch H4 and wire H5 to main I08.
  • Coarse rheostat arm I4 (Fig. 4) may be manually adjusted because of the lost motion coupling provided by pin I6 and screw I2, and by suitable adjustment of manual rheostat H3 in setting up the apparatus for operation a position of substantial balance may be obtained.
  • the alarm may be viaible, audible, or of any other type.
  • switch H4 When switch H4 is in the down for automatic operation, current impulses pass from rheostat H3 through switch H4 and by wire I45 to motor control rheostats 62 and I5, and return by wires I46 and I4I to the back contact I42 of the feeder relay, and then by wire I44 to feeder motor coil II and by common return III to main I09.
  • This circuit just described through the resistances 62 and I5 and motor coil I I may be designated as the vibratory conveyor regulating circuit.
  • the feed decrease circuit for the rheostat operating motor 52 passes from main I08 by wires I I5 and H5 through switch H4, and by wires'H'l and III to manual rheostat '50, and by wire- III! to motor terminal H9 of the rheostat motor 52, and by terminal I22, limit switch I! and wire I43 to a terminal I50 of the automatic feed decrease control relay I5I, and when the relay coil is actuated, across the relay element I52 to wire I53 and then to common return III.
  • the feed increase circuit for the rheostat operating motor passes from motor terminal I I9 to motor terminal I20, across limit switch I8 and by wire I56 to terminal I60 of the automatic feed increase control relay NH, and across the relay element I62 to wire I53 which leads to common. return III. It will be seen that the completion of the feed decrease and feed increase circuits for the rheostat operating motor 52 depends upon the position of limit switches IT and I8, and upon the position of the relay elements I52 and I62 of control relays I5I and I6I respectively.
  • the coil of control relay i-5I is actuated when the conveyor on the scale is overweight and this may be referred to as the decrease feed relay.
  • the coil of relay I6I is actuated when the load on the con veyor scale is underweight and thus serves to increase the feed and may be referred to as the increase feed relay.
  • switch element I2I makes contact with contact I24, and current passes across common return II I and wire I 23 to switch I2I, and by wire I63 to actuating coil I66 of the increase feed relay I6I, and then by wire I61 through a condenser I68 and by wire I I1 back to the switch I I4, and by wires III and H to main I08.
  • switch I2I makes contact with the contact I25, and current flows from III, through wire I1I to actuating coil I12 of the decrease feed relay I5I, and by wire I13 through condenser I68 and wire II1 back to the switch H4 and thence to main I08.
  • the condenser I68 serves to reduce arcing when the contacts are made or broken.
  • the speed of the vibratory conveyor 1 will continue to increase until the belt conveyor becomes properly loaded, whereupon switch I2I will be moved by the scale to mid position; to open the feed increase circuit of the rheostat motor and the resistances 62 and 15 in the .feeder circuit remain at an increased value as long as the vibratory conveyor is feeding material at the proper rate to the scale. Should the feed to the scale become too rapid switch i2I makes contact at I25, and current now may pass through wire I11 to actuate relay coil I12 of the feed decrease relay I55. This allows current flow through the feed decrease circuit of the rheostat motor to drive the rheostat arms SI and It to decrease the resistance in the feeder circuit and thus increase the feed from the vibratory conveyor. As previously explained, limit switch 11 and 18 are opened should the rheostat motor 52 move arms 65 and 14 to their limits of movement in either direction.
  • the apparatus so far described preferably is used together with an anti-flushing mechanism to control flow from the hopper to the vibratory conveyor.
  • a normally open antifiush control switch I15 and a normally closed anti-flush switch I16 are provided in control boxes 41 on the scale to be actuated by the scale.
  • the switch I 15 may be referred to as the overload switch. Should the belt conveyor on the scale become overloaded considerably more than is necessary to actuate switch I2 I, the switch I15 is closed by the movement of the scale, and thus current may fiow from main I I5 by wire I19 across switch I15, and by wire I8I to feeder relay coil I11, and by wire I82 across switch I16, and by wires I83 and III to main I09.
  • the hopper control motor 20 ( Figures 1 and 8) has a circuit from terminal I9I by wires I and I89 to relay contact I81 01' relay I88, and by wires I86 and I85 to wire III. From motor terminal ISI the circuit continues to terminal I92 and by wire I93 through relay contact I94 to wire I95 and by wire I96 to wire I I5 connected to main I08.
  • This switch is connected by wire 201 to one end of hopper vibrator rheostat H0, and by wire 208 to the other end of rheostat H0, and serves to short circuit the rheostat and increase the current supply to the hopper vibrator motor. This is an important feature in curing a flushing condition for the increased vibration drives out entrained air which is an important factor in causing flushing.
  • Timer 2I0 comprises a motor 2I I and contacts 2I2 the motor being operated through the circuit comprising Wire 2 I3 connected to main I09 and wires 2, 2I5 connected to main I08.
  • Contacts 2I2 are intermittently connected at timed intervals, which may be adjusted as desired, such as at intervals of five seconds.
  • One side of contact 2I2 is connected by wires 2I6, 2H and 2I5 to main I08, and the other side is connected by wire 2" to a terminal 2I8 n timer 220.
  • Motor 22I of. timer 220 has one terminal connected by wires 223, 224 and 2I5 to main I08, and the other motor terminal is connected by wire 225 to a terminal 226.
  • a relay coil 228 is provided in timer 220, and contacts 230 are actuated by motor 22I at timed intervals which are set at a greater value than those of timer 2
  • contacts 230 are in contactcurrent can flow through relay coil 228 and contact 230 by wires 23I and 232 contact element 233 of increase Iced relay IN, or contact element 234 of decrease feed relay I5I, so that only when the coils of the increase or decrease reed relays are actuated coil 228 can be actuated.
  • Wire 23I is connected to switch element 235 of the timer 220, and when cell 228 is actuated a holdin circuit is made by wire 236 and switch element 235 around the coil. Thus, once coil 228 is actuated to move switch element 235, a current continues to flow through coi1228 as long as either relay I5I or I6I is actuated and the opening of contact 230 does not ail'ect coil 228. Switch element 231 thus is moved into contact with contact 2I8 and current flows by wire 238 to relay coil 23! or MI. I!
  • the relay coil 20I will be actuated from wires 242, 233 relay contacts 231, 2I8, wire 2", contact 2I2 wires 2E6, 2M and 2I5 to the main I08, the circuit being completed by wire 203 through limit switch wire 205 and relay contact 206 through wires and 'iII to the main I09, and as relay coil 28% ml be actuated only when contact 2I2 completes the circuit, the hopper motor 20 will be intermittently actuated for periods determined by the timing of timer 2I0.
  • the timer 220 regulates the frequency with which timer 2I0 can actuate the hopper motor. However, if the overfeed condition continues long enough for switch I15 to be closed relay coil I11 is actuated to continuously energize motor 20 and fully close the hopper.
  • the relay coil 239 will be actuated by current passing from relay element 231 by wire 238 to coil 239 and by wire 246 across limit switch 240, wire 241 and relay element 248, and contact 2I2 controls the period of actuation whiletimer 220 regulates the -frequency with which timer 2 I0 can actuate the motor hopper 20.
  • the hopper will be opened by steps until fully opened at which time limit switch 240 opens to deenergize the motor 20.
  • the purpose of this arrangement is to provide the opening of relay I6I, or the extreme closing or the hopper occurs and limit switch 202 is actuated, and operation of switch I15 then actuates the relay I43 to stop operation of the vibratory conveyor.
  • a remote push button control 255 may be provided to position the hopper for any desired feed opening.
  • Push button 256 has contactors 251 and 258, and push button 260 has contactors 26I and 262.
  • Contacts 263, 264, 265 and 266 are provided for push button 256.
  • Contact 265 is connected by wires 268 and I85 to Wire III connected to main I09.
  • button 256 is pushedcurrent is conducted across contactor 258 to contact 263 and by wire 261 to limit switch 202, thence by wire 203 to relay coil 20I and by wires 200, 210 and 2H to contact 264 thence across contactor 256 to contact 266 and by wire 212 to Wire II5 connected to the main I 08.
  • relay coil 20I the hopper motor 20 may be actuated for any desired time interval to open it the desired extent.
  • push button 260 is pushed to connect contacts 215 and 216 by contactor 262, and contacts 211 and 218 by connector 26I.
  • Current is supplied from wires I85 and 28I to contact 218, across contactor 26I to contact 211, by wire 282 across limit switch 240 and by wire 246 to coil 239, by wires 245, 242, 210 and 283 to contact 216, across contactor 262 to contact 215 and by wires 284 and 212 to wire II5 connected to main I08.
  • the hopper motor 20 may be actuated for any desired time intervalto close the feed opening to any desired extent.
  • an electrically operated vibratory motor a vibratory conveyor operated by said motor.
  • a controller member carrying a continuously discharging con- Veyor located to receive material from the vibratory conveyor, fine impedance adjustment means and coarse impedance adjustment means in the vibratory motor circuit, a reversible motor, direct motion transmitting means between said reversible motor and both saidimpedance means including a lost motion connection between the reversible motor and coarse impedance adjustment means, means operated by the controller member to drive the reversible motor in one direction to increase the impedance of the vibratory motor circuit and reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and means operated by said controller member to drive the reversible motor in reverse direction to decrease the impedance of the vibratory motor circuit and increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight.
  • anelectrically operated vibratory motor a vibratory conveyor operated by said motor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, line impedance adjustment means and coarse impedance adjustment means in series in the vibratory motor circuit, a reversible motor, direct motion transmitting means between said reversible motor and both said impedance means including a lost motion connection between the reversible motor and coarse impedance adjustment means, means operated by the controller member to drive the reversible motor in one direction to increase the impedance of the vibratory motor circuit and reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight.
  • an electrically operated vibratory motor a vibratory conveyor operated by said motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplyin material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, means governed by the controller member for moving the hopper closer to or farther away from the vibratory conveyor to govern the feed opening between th hopper and conveyor, and means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight and to increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight.
  • an electrically operated vibratory motor a controlled vibratory conveyor trough operated by said motor, a movable hopper having an open mouth adjacent the vibratory conveyor trough for supplying material to the vibratory conveyor trough, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor trough, means governed by the controller member for moving the hopper closer to or farther away from the vibratory conveyor trough to govern the feed opening between the hopper and conveyor trough, fine impedance adjustment means and coarse impedance adjustment means in series in the vibratory motor circuit, a reversible motor, motion transmitting means between said reversible motor and both said impedance means including a lost motion connection between the reversible motor and coarse impedance adjustment means, means operated by the controller member to drive the reversible motor in one direction to increase the impedance of the vibratory motor circuit and reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and means operated by
  • an electrically operated vibratory motor a vibratory conveyor operated by the motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplying material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, hopper moving means for moving the hopper closer to or farther away from the vibratory conveyor to govern the feed opening between the hopper and conveyor, control means governed by the controller member and including impulse timing means for actuating said hopper moving means in impulses, and means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and to increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight.
  • an electrically operated vibratory motor a vibratory conveyor operated by the motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplying material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, hopper moving means for moving the hopper closer to or farther away from the vibratory conveyor to govern the feed opening between the hopper and conveyor, control means governed by the controller member and including period limiting means and impulse timing means for actuating said hopper moving means in impulses, and means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and to increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight.
  • an electrically operated vibratory motor a vibratory conveyor operated by the motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplying material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, hopper moving means for moving the hopper closer to or farther away from the vibratory conveyor to govern the feed opening between the hopper and conveyor, control means governed by the controller member and including period limiting means and impulse timing means for actuating said hopper moving means in impulses, a variable impedance in the vibratory motor circuit, a reversible motor for varying said impedance to increase or decrease the magnitude thereof, means operated by the controller member to drive the reversible motor in one direction to increase the impedance magnitude and reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and means operated by the controller member to drive the reversible motor in the opposite direction to decrease the impedance magnitude and increase the current supplied to the vibratory vibr
  • an electrically operated means a controller member, fine impedance adjustment means and coarse impedance adjustment means in the circuit of said first mentioned means, a reversible motor, motion transmitting means between said reversible motor and both said impedance means including a lost motion connection between the reversible motor and one of said impedance means after which they are both varied simultaneously and continuously to depletion unless reversed, and, means operated by the controller member ior driving said reversible motor in either direction to control said first mentioned means.
  • an apparatus of the character described means operated by direct current impulses, a controller member, fine impedance adjustment means and coarse impedance adjustment means in the circuit of said first mentioned means, a reversible direct current motor, motion transmitting mea'ns between said reversible motor and both said impedance means including a lost motion connection between the reversible motor and one of said impedance adjustment means after which they are both varied simultaneously and continuously to depletion unless reversed, and means operated by the controller member for directing the current to drive said reversible motor in either direction to control said first mentioned means.
  • an electrically operated vibratory motor a vibratory conveyor operated by said motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplying material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, means governed by the controller member for moving the hopper against the vibratory conveyer to close the feed opening between the hopper and conveyor, means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight and to increase 'the current supplied to the vibratory motor when the weight of the material or the discharging conveyor is underweight, and means to cut oil the supply of current to the vibratory motor when an extreme overweight on the discharging conveyor occurs.
  • an electrically operated vibratory motor a vibratoryconveyor operated by said motor, a movable hopper having an open mouth adjacent said vibratory conveyor for supplying material thereto, a hopper vibrator, a control impedance for said hopper vibrator, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight and to increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight, means operated by an extreme overweight condition on the discharging conveyor to cut oil the supply of current to the vibratory motor and for moving the hopper against the vibratory conveyor to close the feed opening, means operated by said latter means to increase the current supply of the hopper vibrator.
  • an electrically operated vibratory motor a vibratory conveyor operated by said motor, a movable hopper having an open mouth adjacent said' ceive material from the vibratory conveyor, means operated by the controller member to reduce the current supplied to the vibratory motor when the weight or the material on the discharging con.- veyor is overweight and to increase the current supplied to the vibratory motor'when the weight 01' the material on the discharging conveyor is underweight, means operated by an extreme overweight condition on the discharging conveyor for moving the hopper against the vibratory conveyor to close the reed opening and means operated by said latter means to increase the current supply or the hopper vibrator.
  • an electrically operated vibratory motor a vibratory conveyor operated by said motor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, a variable impedance in the vibratory motor circuit, a reversible motor for varying said impedance, a decrease feed relay and an increase feed relay to control said reversible motor, means governed by the controller to actuate said relays, a movable hopper having a mouth for supplying material to said conveyor, a hopper positioning motor, controller actuated means to energize said motor to close the hopper mouth when an extreme overweight condition occurs on the discharging conveyor, means to stop the vibratory conveyor, means to vibrate said hopper, impulse timing means to move the hopper by increments toward sopen or closed position between overweight and underweight extremes of said discharging conveyor, and manually operated remote control means to position said hopper.
  • a variable impedance structure the combination of a fine impedance adjustment means and a coarse impedance adjustment means, a reversible motor arranged to drive both of said impedance adjustment means to vary the impedance thereof, a lost motion connection between the motor and one impedance adjustment means to permit movement of the other impedance adjustment means in either direction until the lost motion is. taken up after which both of said impedance adjustment means are moved continuously and simultaneously to depletion unless the motor is reversed.

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  • Jigging Conveyors (AREA)

Description

Oct. 28, 1947. G. D. ALVORD DRY FEEDING MACHINE HAVING MEANS RESPONSIVE TO WEIGHT OF MATERIAL ALREADY DISCHARGED FROM AN AUTOMATICALLY MOVABLE HOPPER Filed Oct. 16, 1943 5 Sheets-Sheet l Inventor GROVE a ALI/09D Gttomcg Oct. 28, 1947. G. D. ALvol-m DRY FEEDING MACHINE HAVING MEANS RESPONSIVE TO WEIGH ARGED FROM AN AUTOMATICALLY MOVABLE HOPPER ALREADY DISCH Filed Oct. 16, 1943 T 0F MATERIAL 5 Sheets-Sheet 2 W594 TOR MOTOR 10/ 7 III A 4 CONVEYOR MOTOR 123" SGALE SWITCH INVENTO GROVE D. ALVORD ATTORNEY Oct. 28, 1947. ALVORD 2,429,864
DRY FEEDING MACHINE HAVING MEANS RESPONSIVE TO WEIGHT OF MATERIAL ALREADY DISCHARGED FROM AN AUTOMATICALLY MOVABLE HOPPER Filed Oct. 16, 1943 5 Sheets-Sheet I5 Snwntor GROVE D. ALI 0R0 attorney Oct. 28, 1947.
. G. D. ALVOR DRY FEEDING MACHINE HAVING ALREADY DISCHARGED FRO 2,429,864 MEANS RESPONSIVE 'ro WEIGHT OF MATERIAL M AN AUTOMATICALLY MOVABLE, HOPPER Filed Oct. 16, 1943 5 Sheets-Sheet 4 Snuentor GROVE 0. ALI/0RD Oct. 28, 1947. G. D. ALVORD 2,429,864
DRY FEEDING MACHINE HAVING MEANS RESPONSIVE T0 WEIGHT OF MATERIAL ALREADY DISCHARGED FROM AN AUTOMATICALLY MOVABLE HOPPER Filed Oct. 16, 1943 5 Sheets-Sheet 5 MANUAL HOPPER POSITION CONTROL Q: g E b, E 8
A U TOMA 776 RE C T lF/E RS 3nncntor Patented Oct. 28, 1947 DRY FEEDING MACHINE HAVING MEANS RESPONSIVE TO WEIGHT OF MATERIAL ALREADY DISCHARGED FROM AUTO- MATICALLY MOVABLE HOPPERS Grove D. Alvord, Indiana, Pa., assignor to Syntron Company, Homer City, Pa., a corporation of Delaware Application October 16, 1943, Serial No. 506,476
The present invention relates to improvements in dry feeding machines for continuously or intermittently feeding or conveying materials at a controlled or uniform rate, Certain subcombinations herein disclosed have utility apart from the general combination, and are part of the invention. I
It is an object of the present invention to provide a bulk feeding apparatus which will feed bulk material at a desired, rate without hunting.
Another object is the provision of a bulk feeding apparatus which may be controlled to prevent flushing of material.
Still another object of the invention is to provide a novel control apparatus for controllin an electrical device to secure substantially uniform operation thereof.
Another object is the provision of a bulk feeding machine that is of simple construction, is dependable, and which will not tend to hunt.
According to the present invention, there is provided an adjustable electrically controlled vibratory feeder or conveyor unit having a variable impedance in its circuit and which discharges onto a controller having a continuously discharging receiver, and a reversible motor operated by the controller in either direction varies the impedance to control the vibratory feeder and provide a predetermined or substantially constant rate of feed of material to the controller. The control means for the reversible motor preferably null point whereby the reversible motor is supplied with current when the controller is i'erably, the impedance is :al parts, example, a coarse part and e part-(ans. were is a lost motion connecbetween the reversible motor and one part he impedance means so that part becomes a reserve and operates only after the directly con nested part has operated. Preferably the corn troiler is a scale carrying a uniformly moving endless belt conveyor, and operating overweight and underweight switch means with a null point to control the direction of operation of the reversible motor, and not actuate the reversible motor when the scale is in balance. This control unit including the reversible motor and plural impedances including one or more reserve impedances, also has utility apart from dry feeding machines.
The apparatus preferably includes an antiflush device to prevent flushing action from the source of supply to the vibratory conveyor, this antifiushing device being controlled by the controller, and its action may be to entirely cut oil? 15 Claims. I (Cl. 222-55) til the supply 'in cases of extreme flushing. The hopper or other source of supply preferably has a vibrator, and when the. supply is cut oil in cases of extreme flushing the action of the hopper vibrator is increased to drive out entrained air from the material. If desired time impulse means is provided to cut off the supply in increments, unless extreme flushing occurs, said means also serving to increase the supply in increments. The supply preferably is controlled by a hopper located adjacent a conveyor trough, and by moving the hopper near or away from the conveyor trough the feed opening therebetween is controlled.
The invention will be described in greater'detail in connection with the accompanying drawing wherein is shown preferred embodiments of the invention by way of example, and wherein:
Figure l is a side view of a preferred embodiment,
Figure 2 is an end view of Figure 1,
Figure 3 is a side view of the control me'chanism, with parts broken away,
Figure l is a plan view of omitted,
Figures 5 and 6 are side views of switches,
Figure '7 is a wiring diagram illustrating operation of a simplified modification, and
Figure 8 is a wiringdiagram illustrating operation of the modification. shown in Figure 1.
Referring to the drawing, Figure 1, there is provided a frame i which may be constructed of angle iron, and a conical hopper 2 is supported from the frame by cables passing through U- bolts i on the hopper and having their ends se cured to the frame in any suitable manner. The open mouth 6 of the hopper is disposed at an angle to the axis of the hopper and terminates adjacent a conveyor trough 5 having its bottom portions disposed parallel with the open bot-- tom 6 of the hopper and providing a feed open ing therebetween. The conveyor is supported on a base 9 by means of a rear cantilever spring l0 and a front motor l l, and the base 9 is supported from the frame by vibration members 12. The conveyor mounting and mode of operation is substantially-as disclosed and claimed in Patent No. 2,187,717 issued to Carl S. Weyandt, January 13, 1940. A suitable hopper vibrator I3 is mounted on the hopper, this vibrator preferably being Figure 3, with part the limit constructed and operated as disclosed in said patent. It will be seen that the hopper may be pivoted about its supporting cables 3 to bring the open edge or mouth 6 into close or substantial coincidence with the bottom I of the vibratory conveyor trough to shut oi! the feed from the hopper, or the feed from the hopper may be reduced or increased as desired by varying or ad- Justing the feed opening between bottom 3 and the hopper mouth 3. The hopper and conveyor thus cooperate to form a valve.
An arm I5 is pivoted to the side of the hopper in any suitable manner, and a crank II linked thereto is mounted to rotate with a shaft I1. An indicator arm I3 cooperating with a scale I3 shows the position of the hopper. A motor 20, preferably of the torque type. is provided to rotate shaft II through gears or the like to position the hopper and thus control the feed opening. Of, if desired, the hopper may be positioned manually.
A second frame 2I-, which may be made integral with the frame I, is located adjacent thereto and supports a scale designated generally at 22. This scale may be of any suitable type or construction and as shown has a load pan or platform 23, and counterpoise arms 24 and 25 carrying counterpoises 26 and 21. Two pairs of straps 23 and 29 are secured to the platform 23 in any suitable manner and carry a conveyor frame 3| in which is mounted rollers 32 and 33 having an endless conveyor belt 34 passing over the rollers. Guard plates 35 are provided to prevent material spilling over the sides. A constant speed motor 36, which may be of the synchronous type, is suitably secured to the frame 2| to drive the belt conveyor at a uniform speed, as for example by a driving sprocket 31 on its shaft which through a suitable chain and countershaft drives a sprocket 4| which in turn drives the conveyor through a chain 42 and sprocket 43 mounted on one roller shaft of the conveyor. The swinging mo ement of the conveyor frame is limited by a torque bar which is not here shown and is disclosed and claimed in the application of Carl S. Weyandt Serial No. 362,500, filed October 24, 1940, now Patent No. 2,340,030, dated January 25, 1944, for Weighing conveyor. A brush 44 is suitably secured to the conveyor frame for wiping the belt.
Mounted in housing 45 and 45 on the frame of the scale are switch contacts of suitable construction, as for example, vacuum enclosed contacts for controlling the weighing action, and in housing 41 are antifiushing switches to control flushing from the hopper. The weight controlling mechanism first will be described. Located in a suitable control housing (not shown) which preferably is apart from the scale, is a base member 5| (Figs. 3 and 4) upon which is mounted a weighing control motor 52 of the reversible type and which contains reduction gearing in the housing whereby the worm 53 on shaft 54 is driven at a very slow speed. A manually operated rheostat 50 is provided in the circuit of motor 52. A shaft 55 is suitably journalled in the'frame and is driven by worm 53 engaging worm wheel 56thereon. At one end shaft 55 carries a pinion 5'! meshing with a spur gear 58 mounted on a shaft 59 which carries a contact arm 6| around the coiled wire vernier rheostat 62. One terminal of the rheostat is provided at 33v and a contact member 64 electrically connected to the contact arm BI has a terminal 65. The rheostat coil has a second terminal 66 which is suitably connected to terminal 65.
Shaft 55 carries a second pinion 38 at its other end which meshes with a spur gear 39 journalled for rotation on stub shaft II, and a hub I0 on gear 69 has a screw 12 or other projection. Shaft 1| is suitably coupled to a shaft II which carries a contact arm 14 about a coiled wire coarse rheostat II, and a pin 13 extends from shaft 1| into the path of movement of screw I2. Thus gear 03 may be rotated through almost from one extreme to the other before screw I2 engages pin It to move contact I4 of the coarse rheostat.
Limit switches enclosed in boxes I1 and ll of suitable construction ar provided to stop operation of motor 52 and may be employed to actuate an alarm. -'Ihe mechanism for switch 11 comprises a push rod 3| extending from the box for actuating the switch, and an actuating arm 32 is pivoted at 33 on the frame 34 and has an adjustable pusher 35 adapted to engage the push rod 3|, and a pin 30 limits upward movement of the arm 32. Arm 32 has an extension 31 adapted to extend into the path of an actuating pin 33 on gear 53 by which the-arm is depressed to cause pusher 35 to move push rod 3| and open the switch. Limit switch I3 has a push rod 9| extending therefrom, and an actuating arm 92 is pivoted at 33 and carries a pusher 34. A pin 35 limits downward motion of arm 32. Arm 32 has a similar extension 31 adapted to extend into the path of an actuating pin 33 on gear 53 by which the arm 32 is elevated to cause pusher to move push rod 3| and open the switch.
The operation of the apparatus so far described will be explained. The pin 13 will normally be approximately 180 from screw I2. When the motor 52 is actuated by the weight control switch in one direction, by reason of the load on the conveyor belt being excessive, the vernier rheostat arm 5| on shaft 53 is rotated through worm 53, worm wheel 53, shaft 55, pinion 51, and spur gear 53 on shaft 53 to increase the resistance in the vibratory conveyor circuit thus reducing the amplitude of vibration of the vibratory conveyor I to reduce the amount of material being fed therefrom onto the belt conveyor 34. At the same time pinion 68 on shaft 55 rotates gear 53 but the resistor arm 14 of coarse resistor 15 is not actuated thereby at first because the relative angular positions of pin 16 and screw I2 allows gear 53 to rotate approximately 180 before screw 12 engages pin I6 to rotate shaft H and contact arm 14. Thus, if the condition causing overweight of the belt conveyor persists the operation of the vibratory conveyor first will be reduced slowly by shifting of arm BI and then more rapidly as both arm 14 of the main rheostat and arm 3| of the vernier rheostat are rotated until the belt conveyor becomes slightly underweight or attains the proper weight. If the belt conveyor becomes underweight the underweight switch is actuated to cause the direction of motor 52 to be reversed to cause first a reverse rotation of vernier rheostat arm 5| to reduce the resistance, and then, if necessary, reverse rotation of coarse rheostat arm I4, until substantial balance is reached. In balanced condition the circuit of motor 52 remains open.
An electrical operating circuit for one modification is shown diagrammatically in Figure 7. The dual electrode vacuum tube rectifiers |0I and I02 have the usual anodes I03 and I04 and cathodes I05 and I05 and a transformer I01 to provide-a heating current from the mains I03 and I03 of an alternating current source. It will be understood that any suitable type of rectifier may be provided in place of the vacuum tube rectifiers, such as dry disk, electrolytic or the like. The belt conveyor motor 36 is connected to mains I08 and I09 through a suitable switch. The hopper vibrator motor I3 is actuated by the current impulses supplied through tube IOI and which are regulated by the manual operated rheostat I I0, and the circuit is completed through wire III and load switch H6. The vibratory conveyor motor II is actuated by the spaced current impulses supplied through tube I02, ammeter H2 and which are regulated by the manually operated rheostat H3, when the switch H4 is in the upward position shown for manual operation, the circuit being completed through wire I I I.
When switch H4 is in the down or automatic operating position the automatic weighin control reversible motor 52 is connected to the power line I08 through a lead wire H5, switch H4, lead wire III, manual rheostat 50 and lead wire II 8 to a motor terminal H9, and assuming limit switch I! closed as shown, terminal I20 is con- I nected by switch I! to limit switch terminal I29, and by wires I28 to scale controlled contact I24. The scale control switch has a movable contact arm I2I operated by the scale and connected by lead wire I23 and common return wire III to the main I09. Contact I connects by lead wire I26 to a terminal I21 0f the limit switch I9, and a condenser I3I is supplied between the limit switches to reduce arcing and prevent passage of direct current impulses simultaneously through both switches.
During automatic operation the current impulses for the conveyor motor II passthrcugh tube I02, manual rheostat H3 and through motor operated rheostats 62 and 15 to the vibratory conveyor motor II, and by wire III to main I09. The motor 52 which controls the rheostats 62 and I5 is in shunt with the circuit of the vibra-- tory conveyor motor, and what may be called the scale underlcad control circuit extends from main I09 through wires HI, I23, switch contacts I2I, I24, wire I28, switch 11, motor terminals I20, H9, wire H8, rheostat 50, wire HI, switch H4 and wire H5 to main I08. Or, when switch arm I2I contacts contact I25, the scale overload circuit of motor 52 is completed through switch contacts I2I, I25, wire I26, switch terminal I21, switch 18, motor terminals I22 and H9, wir H8, etc. to main I08. Coarse rheostat arm I4 (Fig. 4) may be manually adjusted because of the lost motion coupling provided by pin I6 and screw I2, and by suitable adjustment of manual rheostat H3 in setting up the apparatus for operation a position of substantial balance may be obtained.
When the scale is in balance, the switch arm I2I is in mid position as shown in Figure? and motor 52 is not actuated. When the load on the belt conveyor is too light the scale brings switch arm I2I into contact with contact I24 thus closing the scale underload circuit of motor 52 through wire I28, limit switch TI and motor terminals I20, H9 to pass direct current impulses through the motor to rotate it in one direction and first move rheostat arm GI then, if necessary, move both arm 6i and coarse rheostat arm 14 to increase the current supplied to the vibratory conveyor motor II and increase the feed to the scale. Should the rheostat arms iii and I4 approach too near their ends the limit switch I1 is opened by the pin 88 (Fig. 3) engaging extension 81 to disconnect the circuit of motor 52 and stop the motor and at the same time allow current from wire I23 to pass from contact I24 across switch I2 I, through wire I23 and through limit switch 11 and by lead wires I34 and I35-to an alarm connection, the wire I36 serving as the other alarm connection. The alarm may be viaible, audible, or of any other type.
When the load on the belt conveyor is too great the switch arm I2I contacts with contact I25 thus causing direct current impulses to pass through wire I26 and limit switch I8 to motor terminals I22, H9 to reverse the motor 52 and drive the rheostat arms 6| and I4 in reverse direction to decrease the current supplied to the vibratory conveyor motor II to decrease the teed to the scale. Should the rheostat arms 6| and I4 approach too near their ends the limit switch I8 is opened by the pin 98 (Fig. 3) engaging extension 91 to disconnect the circuit of motor 62 and stop the motor and at the same time allow current to pass from contact I 25 across switch I, and through wire I26 and through limit switch I8 and wire I35 to the alarm connection.
In Figure 8, wherein like parts are referred to by like reference numerals, is shown a further modification including an anti-flushing mechanism to control flow from the hopper. When switch H4 is in the up for manual control position the current impulses for the vibratory conveyor motor II pass through rheostat H3, switch H4 and pass by wires I40 and MI to the back contact I42 of feeder relay I43, then by wire I44 to motor coil II and through common return III. When switch H4 is in the down for automatic operation, current impulses pass from rheostat H3 through switch H4 and by wire I45 to motor control rheostats 62 and I5, and return by wires I46 and I4I to the back contact I42 of the feeder relay, and then by wire I44 to feeder motor coil II and by common return III to main I09. This circuit just described through the resistances 62 and I5 and motor coil I I may be designated as the vibratory conveyor regulating circuit.
The feed decrease circuit for the rheostat operating motor 52, passes from main I08 by wires I I5 and H5 through switch H4, and by wires'H'l and III to manual rheostat '50, and by wire- III! to motor terminal H9 of the rheostat motor 52, and by terminal I22, limit switch I! and wire I43 to a terminal I50 of the automatic feed decrease control relay I5I, and when the relay coil is actuated, across the relay element I52 to wire I53 and then to common return III. The feed increase circuit for the rheostat operating motor passes from motor terminal I I9 to motor terminal I20, across limit switch I8 and by wire I56 to terminal I60 of the automatic feed increase control relay NH, and across the relay element I62 to wire I53 which leads to common. return III. It will be seen that the completion of the feed decrease and feed increase circuits for the rheostat operating motor 52 depends upon the position of limit switches IT and I8, and upon the position of the relay elements I52 and I62 of control relays I5I and I6I respectively. The coil of control relay i-5I is actuated when the conveyor on the scale is overweight and this may be referred to as the decrease feed relay. The coil of relay I6I is actuated when the load on the con veyor scale is underweight and thus serves to increase the feed and may be referred to as the increase feed relay. These relays are actuated by the scale as will now be described.
When the belt conveyor is underweight, switch element I2I makes contact with contact I24, and current passes across common return II I and wire I 23 to switch I2I, and by wire I63 to actuating coil I66 of the increase feed relay I6I, and then by wire I61 through a condenser I68 and by wire I I1 back to the switch I I4, and by wires III and H to main I08. When the scale conveyor is overloaded the switch I2I makes contact with the contact I25, and current flows from III, through wire I1I to actuating coil I12 of the decrease feed relay I5I, and by wire I13 through condenser I68 and wire II1 back to the switch H4 and thence to main I08. The condenser I68 serves to reduce arcing when the contacts are made or broken.
The operation of the circuits so far described now will be explained. Assuming the apparatus is operating and material is being fed from the vibratory conveyor I "to the belt conveyor 34 on the scale, if the feed to the scale becomes too slow so that the scale becomes underweight, the switch arm I2I contacts at I24, and current passes from main I09 by wires III and I23 through switch I2I, and by wire I65 to actuate the relay coil I66, and return by wires I61 and I I1 to the switch H4 then by wire H5 and wire I I5 to main I08. This Causes element I62 to move upward and make contact so that new current may flow from main I08 by wires 5 and H5 through switch Ill and through wires H1 and lI1' rheostat 50 wire I I8 to motor terminal H9, and then through terminal I20 and limit switch 18 and b wire I58 across relay element I62 and by Wires I53 and III to main A06. Thus motor 52 is actuated to drive the rheostat arms 6i and 14 to decrease the resistances 62 and and increase the feed from the vibratory conveyor 1.
The speed of the vibratory conveyor 1 will continue to increase until the belt conveyor becomes properly loaded, whereupon switch I2I will be moved by the scale to mid position; to open the feed increase circuit of the rheostat motor and the resistances 62 and 15 in the .feeder circuit remain at an increased value as long as the vibratory conveyor is feeding material at the proper rate to the scale. Should the feed to the scale become too rapid switch i2I makes contact at I25, and current now may pass through wire I11 to actuate relay coil I12 of the feed decrease relay I55. This allows current flow through the feed decrease circuit of the rheostat motor to drive the rheostat arms SI and It to decrease the resistance in the feeder circuit and thus increase the feed from the vibratory conveyor. As previously explained, limit switch 11 and 18 are opened should the rheostat motor 52 move arms 65 and 14 to their limits of movement in either direction.
The apparatus so far described preferably is used together with an anti-flushing mechanism to control flow from the hopper to the vibratory conveyor. For this purpose a normally open antifiush control switch I15 and a normally closed anti-flush switch I16 are provided in control boxes 41 on the scale to be actuated by the scale. The switch I 15 may be referred to as the overload switch. Should the belt conveyor on the scale become overloaded considerably more than is necessary to actuate switch I2 I, the switch I15 is closed by the movement of the scale, and thus current may fiow from main I I5 by wire I19 across switch I15, and by wire I8I to feeder relay coil I11, and by wire I82 across switch I16, and by wires I83 and III to main I09. This moves upwardly the back contact element I42 of the feeder relay thus opening the vibratory conveyor circuit to stop operation of the vibratory conveyor and stop the supply of material to the belt conveyor on the scale. This action occurs in extreme cases where the hopper has flushed badly onto the vibratory conveyor and thus has caused extreme overloading of the belt conveyor. The belt conveyor continues to operate and the relay holding circuit, including wire I18 and relay contact element I connects coil I11 with wire I I5 and hold the back contact open until the belt conveyor becomes sufficiently unloaded to open switch I18 and break the circuit of coil I11, whereupon the vibratory conveyor is again energized.
Ordinarily such an extreme condition would be caused y flushing of material from the hopper 2 to the vibratory conveyor 1, and I prefer to provide an arrangement for reducing or closing the feed opening between the hopper and vibratory conveyor to stop the flushing action. The hopper control motor 20 (Figures 1 and 8) has a circuit from terminal I9I by wires I and I89 to relay contact I81 01' relay I88, and by wires I86 and I85 to wire III. From motor terminal ISI the circuit continues to terminal I92 and by wire I93 through relay contact I94 to wire I95 and by wire I96 to wire I I5 connected to main I08. Thus, when switch I15 is actuated to energize relay coil I11 of the feeder relay I43 its contact element I98 completes a circuit from wire Hi to wire 200 through coil 20I of relay I88, and by wire 203 through limit switch 202 of motor 20 and by wire 205 to relay I5I and across middle contact member 206 and by wire I53 to wire I I I. Thus the hopper circuit of motor 20 is completed to actuate the motor and move the hopper 2 continuously to close the feed opening. Motor 20 preferably is of the torque type that may be stalled without injury. When the feed opening becomes closed the limit witch 202 is opened by the motor 20 to open the circuit of relay coil MI and thus open the circuit of the motor. It will be seen that the anti-flush control can operate only when the decrease feed relay coil I12 has been actuated because the contact element 206 thereon is necessary to complete the hopper control circuit. The hopper may be opened manually to the desired feed opening,
I prefer to employ in connection with hopper motor 20 a hopper vibrator rheostat short circuiting switch which is normally open and is closed by motor 20 when the hopper feed opening is closed. This switch is connected by wire 201 to one end of hopper vibrator rheostat H0, and by wire 208 to the other end of rheostat H0, and serves to short circuit the rheostat and increase the current supply to the hopper vibrator motor. This is an important feature in curing a flushing condition for the increased vibration drives out entrained air which is an important factor in causing flushing.
I prefer to employ a timer mechanism to reduce the supply from the hopper to the vibratory conveyor when an overload condition of the belt conveyor exists for a predetermined period of time. This causes the motor 20 to be actuated in steps or impulses to gradually close or gradually open the feed opening between the hopper and vibratory conveyor. Timer 2I0 comprises a motor 2I I and contacts 2I2 the motor being operated through the circuit comprising Wire 2 I3 connected to main I09 and wires 2, 2I5 connected to main I08. Contacts 2I2 are intermittently connected at timed intervals, which may be adjusted as desired, such as at intervals of five seconds. One side of contact 2I2 is connected by wires 2I6, 2H and 2I5 to main I08, and the other side is connected by wire 2" to a terminal 2I8 n timer 220.
Motor 22I of. timer 220 has one terminal connected by wires 223, 224 and 2I5 to main I08, and the other motor terminal is connected by wire 225 to a terminal 226. A relay coil 228 is provided in timer 220, and contacts 230 are actuated by motor 22I at timed intervals which are set at a greater value than those of timer 2| 0, as for example, every thirty seconds. When contacts 230 are in contactcurrent can flow through relay coil 228 and contact 230 by wires 23I and 232 contact element 233 of increase Iced relay IN, or contact element 234 of decrease feed relay I5I, so that only when the coils of the increase or decrease reed relays are actuated coil 228 can be actuated.
Wire 23I is connected to switch element 235 of the timer 220, and when cell 228 is actuated a holdin circuit is made by wire 236 and switch element 235 around the coil. Thus, once coil 228 is actuated to move switch element 235, a current continues to flow through coi1228 as long as either relay I5I or I6I is actuated and the opening of contact 230 does not ail'ect coil 228. Switch element 231 thus is moved into contact with contact 2I8 and current flows by wire 238 to relay coil 23!! or MI. I! decreased feed relay I5I is actuated current flows across contact element 206 thereof by wire 205 across limit switch 202 to relay coil 20I and by wire 200 to contact element I98 of relay element I 43, and if relay coil I11 is actuated the circuit is completed through contact element I98. This actuates the motor 20 to close the feed opening of the hopper as previously described. However, if the increase feed a variation or adjustment of the feed opening only it a condition of increase feed or decrease feed exists or continues long enough to coincide with or extend over the period or contact of timer 220. Timer 2I0 thus controls the length of time 'or duration of the impulse to hopper motor 20, and timer 220 determines how often or how frequently the impulses can occur. Thus if a flush condition exists, over a period of more than thirty seconds the motor 20 will be actuated every five seconds by an impulse to reduce the feed op in increments until the condition is corrected by relay I6I is actuated, current flows across con- 7 tact element 248 thereof by wire 241, across limit switch 240 to relay coil 239 and by wires 245, 242 and 200 to contact element I98. Actuation of relay coil 239 completes the hopper opening circuit of motor 20 by wire I90 across contact element MI and by wires I86 and I85 to wire III, and from motor terminal 250 by wire 25I' across contact element 252 and by wire I96 to wire'II5. Assuming the decrease relay I5I is actuated and that feeder relay coil I11 is not actuated, the relay coil 20I will be actuated from wires 242, 233 relay contacts 231, 2I8, wire 2", contact 2I2 wires 2E6, 2M and 2I5 to the main I08, the circuit being completed by wire 203 through limit switch wire 205 and relay contact 206 through wires and 'iII to the main I09, and as relay coil 28% ml be actuated only when contact 2I2 completes the circuit, the hopper motor 20 will be intermittently actuated for periods determined by the timing of timer 2I0. However, as the opening contact 230 releases relay element 236, the timer 220 regulates the frequency with which timer 2I0 can actuate the hopper motor. However, if the overfeed condition continues long enough for switch I15 to be closed relay coil I11 is actuated to continuously energize motor 20 and fully close the hopper.
Similarly, if the increase feed relay I6I is actuated, the relay coil 239 will be actuated by current passing from relay element 231 by wire 238 to coil 239 and by wire 246 across limit switch 240, wire 241 and relay element 248, and contact 2I2 controls the period of actuation whiletimer 220 regulates the -frequency with which timer 2 I0 can actuate the motor hopper 20. Thus, the hopper will be opened by steps until fully opened at which time limit switch 240 opens to deenergize the motor 20.
The purpose of this arrangement is to provide the opening of relay I6I, or the extreme closing or the hopper occurs and limit switch 202 is actuated, and operation of switch I15 then actuates the relay I43 to stop operation of the vibratory conveyor.
A remote push button control 255 may be provided to position the hopper for any desired feed opening. Push button 256 has contactors 251 and 258, and push button 260 has contactors 26I and 262. Contacts 263, 264, 265 and 266 are provided for push button 256. Contact 265 is connected by wires 268 and I85 to Wire III connected to main I09. When button 256 is pushedcurrent is conducted across contactor 258 to contact 263 and by wire 261 to limit switch 202, thence by wire 203 to relay coil 20I and by wires 200, 210 and 2H to contact 264 thence across contactor 256 to contact 266 and by wire 212 to Wire II5 connected to the main I 08. Thus, by actuating relay coil 20I the hopper motor 20 may be actuated for any desired time interval to open it the desired extent.
If it is desired to close or reduce the feed opening push button 260 is pushed to connect contacts 215 and 216 by contactor 262, and contacts 211 and 218 by connector 26I. Current is supplied from wires I85 and 28I to contact 218, across contactor 26I to contact 211, by wire 282 across limit switch 240 and by wire 246 to coil 239, by wires 245, 242, 210 and 283 to contact 216, across contactor 262 to contact 215 and by wires 284 and 212 to wire II5 connected to main I08. Thus by actuation of relay coil 239 the hopper motor 20 may be actuated for any desired time intervalto close the feed opening to any desired extent.
What I claim as my invention and desire to secure by United States Letters Patent is:
1. In an apparatus of the character described, an electrically operated vibratory motor, a vibratory conveyor operated by said motor. a controller member carrying a continuously discharging con- Veyor located to receive material from the vibratory conveyor, fine impedance adjustment means and coarse impedance adjustment means in the vibratory motor circuit, a reversible motor, direct motion transmitting means between said reversible motor and both saidimpedance means including a lost motion connection between the reversible motor and coarse impedance adjustment means, means operated by the controller member to drive the reversible motor in one direction to increase the impedance of the vibratory motor circuit and reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and means operated by said controller member to drive the reversible motor in reverse direction to decrease the impedance of the vibratory motor circuit and increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight.
2. In an apparatus of the character described,
anelectrically operated vibratory motor, a vibratory conveyor operated by said motor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, line impedance adjustment means and coarse impedance adjustment means in series in the vibratory motor circuit, a reversible motor, direct motion transmitting means between said reversible motor and both said impedance means including a lost motion connection between the reversible motor and coarse impedance adjustment means, means operated by the controller member to drive the reversible motor in one direction to increase the impedance of the vibratory motor circuit and reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight. means operated by the controller member to drive the reversible motor in reverse direction to decrease the impedance of the vibratory motor circuit and increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight, and limit switch means to disconnect said reversible motor when said impedance means reaches its limit.
3. In an apparatus of the character described, an electrically operated vibratory motor, a vibratory conveyor operated by said motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplyin material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, means governed by the controller member for moving the hopper closer to or farther away from the vibratory conveyor to govern the feed opening between th hopper and conveyor, and means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight and to increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight.
4. In an apparatus of the character described, an electrically operated vibratory motor, a controlled vibratory conveyor trough operated by said motor, a movable hopper having an open mouth adjacent the vibratory conveyor trough for supplying material to the vibratory conveyor trough, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor trough, means governed by the controller member for moving the hopper closer to or farther away from the vibratory conveyor trough to govern the feed opening between the hopper and conveyor trough, fine impedance adjustment means and coarse impedance adjustment means in series in the vibratory motor circuit, a reversible motor, motion transmitting means between said reversible motor and both said impedance means including a lost motion connection between the reversible motor and coarse impedance adjustment means, means operated by the controller member to drive the reversible motor in one direction to increase the impedance of the vibratory motor circuit and reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and means operated by the controller member to drive the reversible motor in reverse direction to decrease the impedance of the vibratory motor circuit and increase the current supplied to the vibratory motor when the weight of 12 the material on the discharging conveyor is underweight.
5. In an apparatus of the character described, an electrically operated vibratory motor, a vibratory conveyor operated by the motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplying material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, hopper moving means for moving the hopper closer to or farther away from the vibratory conveyor to govern the feed opening between the hopper and conveyor, control means governed by the controller member and including impulse timing means for actuating said hopper moving means in impulses, and means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and to increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight.
6. In an apparatus of the character described, an electrically operated vibratory motor, a vibratory conveyor operated by the motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplying material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, hopper moving means for moving the hopper closer to or farther away from the vibratory conveyor to govern the feed opening between the hopper and conveyor, control means governed by the controller member and including period limiting means and impulse timing means for actuating said hopper moving means in impulses, and means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and to increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight.
7. In an apparatus of the character described, an electrically operated vibratory motor, a vibratory conveyor operated by the motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplying material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, hopper moving means for moving the hopper closer to or farther away from the vibratory conveyor to govern the feed opening between the hopper and conveyor, control means governed by the controller member and including period limiting means and impulse timing means for actuating said hopper moving means in impulses, a variable impedance in the vibratory motor circuit, a reversible motor for varying said impedance to increase or decrease the magnitude thereof, means operated by the controller member to drive the reversible motor in one direction to increase the impedance magnitude and reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight, and means operated by the controller member to drive the reversible motor in the opposite direction to decrease the impedance magnitude and increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight.
8. In an apparatus of the character described.
an electrically operated means, a controller member, fine impedance adjustment means and coarse impedance adjustment means in the circuit of said first mentioned means, a reversible motor, motion transmitting means between said reversible motor and both said impedance means including a lost motion connection between the reversible motor and one of said impedance means after which they are both varied simultaneously and continuously to depletion unless reversed, and, means operated by the controller member ior driving said reversible motor in either direction to control said first mentioned means.
9. 1m an apparatus of the character described, means operated by direct current impulses, a controller member, fine impedance adjustment means and coarse impedance adjustment means in the circuit of said first mentioned means, a reversible direct current motor, motion transmitting mea'ns between said reversible motor and both said impedance means including a lost motion connection between the reversible motor and one of said impedance adjustment means after which they are both varied simultaneously and continuously to depletion unless reversed, and means operated by the controller member for directing the current to drive said reversible motor in either direction to control said first mentioned means.
10. In an apparatus of the character described, an electrically operated vibratory motor, a vibratory conveyor operated by said motor, a movable hopper having an open mouth adjacent the vibratory conveyor for supplying material to the vibratory conveyor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, means governed by the controller member for moving the hopper against the vibratory conveyer to close the feed opening between the hopper and conveyor, means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight and to increase 'the current supplied to the vibratory motor when the weight of the material or the discharging conveyor is underweight, and means to cut oil the supply of current to the vibratory motor when an extreme overweight on the discharging conveyor occurs.
11. In an apparatus of the character described, an electrically operated vibratory motor, a vibratoryconveyor operated by said motor, a movable hopper having an open mouth adjacent said vibratory conveyor for supplying material thereto, a hopper vibrator, a control impedance for said hopper vibrator, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, means operated by the controller member to reduce the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is overweight and to increase the current supplied to the vibratory motor when the weight of the material on the discharging conveyor is underweight, means operated by an extreme overweight condition on the discharging conveyor to cut oil the supply of current to the vibratory motor and for moving the hopper against the vibratory conveyor to close the feed opening, means operated by said latter means to increase the current supply of the hopper vibrator.
12. In an apparatus of the character described, an electrically operated vibratory motor, a vibratory conveyor operated by said motor, a movable hopper having an open mouth adjacent said' ceive material from the vibratory conveyor, means operated by the controller member to reduce the current supplied to the vibratory motor when the weight or the material on the discharging con.- veyor is overweight and to increase the current supplied to the vibratory motor'when the weight 01' the material on the discharging conveyor is underweight, means operated by an extreme overweight condition on the discharging conveyor for moving the hopper against the vibratory conveyor to close the reed opening and means operated by said latter means to increase the current supply or the hopper vibrator.
13. In an apparatus of the character described, an electrically operated vibratory motor, a vibratory conveyor operated by said motor, a controller member carrying a continuously discharging conveyor located to receive material from the vibratory conveyor, a variable impedance in the vibratory motor circuit, a reversible motor for varying said impedance, a decrease feed relay and an increase feed relay to control said reversible motor, means governed by the controller to actuate said relays, a movable hopper having a mouth for supplying material to said conveyor, a hopper positioning motor, controller actuated means to energize said motor to close the hopper mouth when an extreme overweight condition occurs on the discharging conveyor, means to stop the vibratory conveyor, means to vibrate said hopper, impulse timing means to move the hopper by increments toward sopen or closed position between overweight and underweight extremes of said discharging conveyor, and manually operated remote control means to position said hopper.
14. In a variable impedance structure the combination of a fine impedance adjustment means and a coarse impedance adjustment means, a reversible motor arranged to drive both of said impedance adjustment means to vary the impedance thereof, a lost motion connection between the motor and one impedance adjustment means to permit movement of the other impedance adjustment means in either direction until the lost motion is. taken up after which both of said impedance adjustment means are moved continuously and simultaneously to depletion unless the motor is reversed.
15. The structure of claim 14 which also includes limit switch means for opening the circuit of the reversible motor as both impedance adjustment means reach their limit.
GROVE D. ALVORD.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Certificate of Correction Patent No. 2,429,864. October 28, 1947.
GROVE D. ALVORD It is hereby certified that error appears in the rinted specification of the above numbered patent requiring correction as follows: olumn 13, line 45, claim 10, for "or read on; and that the said Letters Patent should be read with this correction therein that the same may conformto the record of the case in the Patent Oifice.
Signed and sealed this 6th day of January, A. D. 1948.
THOMAS F. MURPHY,
Assistant Oommissioner of Patents.
US506476A 1943-10-16 1943-10-16 Dry feeding machine having means responsive to weight of material already dischargedfrom automatically movable hoppers Expired - Lifetime US2429864A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE951674C (en) * 1953-03-21 1956-10-31 Schenck Gmbh Carl Speed-controlled weighfeeder with a swing mouthpiece
US2897956A (en) * 1955-03-31 1959-08-04 Damond Emile Vibrating chutes
US2932430A (en) * 1956-05-29 1960-04-12 Lockers Engineers Ltd Feeding of granular materials capable of flowing
US3357798A (en) * 1962-11-22 1967-12-12 Takara Koki Kabushiki Kaisha Centrifugal apparatus for obtaining chemical reactions
US3556172A (en) * 1968-06-20 1971-01-19 Int Machinery Corp Method of and apparatus for filling containers
US4566584A (en) * 1984-10-29 1986-01-28 Hi-Speed Checkweigher Co., Inc. Weighing conveyor

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1125705A (en) * 1912-03-22 1915-01-19 Electric Weighing Company Tonnage-regulator.
US1558668A (en) * 1923-11-26 1925-10-27 Carter Mayhew Mfg Company Feed regulator
US1993007A (en) * 1933-12-07 1935-03-05 Thomas M Hunter Voltage regulating means
US2085255A (en) * 1935-12-26 1937-06-29 American Transformer Company Voltage regulator
US2146914A (en) * 1936-04-07 1939-02-14 Pintsch Julius Kg Potential-regulating apparatus
US2164812A (en) * 1936-06-10 1939-07-04 Traylor Vibrator Co Constant-capacity feeder
US2187717A (en) * 1935-11-08 1940-01-23 Carl S Weyandt Vibratory electrical apparatus
US2276383A (en) * 1938-03-10 1942-03-17 Traylor Vibrator Co Constant capacity feeder

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1125705A (en) * 1912-03-22 1915-01-19 Electric Weighing Company Tonnage-regulator.
US1558668A (en) * 1923-11-26 1925-10-27 Carter Mayhew Mfg Company Feed regulator
US1993007A (en) * 1933-12-07 1935-03-05 Thomas M Hunter Voltage regulating means
US2187717A (en) * 1935-11-08 1940-01-23 Carl S Weyandt Vibratory electrical apparatus
US2085255A (en) * 1935-12-26 1937-06-29 American Transformer Company Voltage regulator
US2146914A (en) * 1936-04-07 1939-02-14 Pintsch Julius Kg Potential-regulating apparatus
US2164812A (en) * 1936-06-10 1939-07-04 Traylor Vibrator Co Constant-capacity feeder
US2276383A (en) * 1938-03-10 1942-03-17 Traylor Vibrator Co Constant capacity feeder

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE951674C (en) * 1953-03-21 1956-10-31 Schenck Gmbh Carl Speed-controlled weighfeeder with a swing mouthpiece
US2897956A (en) * 1955-03-31 1959-08-04 Damond Emile Vibrating chutes
US2932430A (en) * 1956-05-29 1960-04-12 Lockers Engineers Ltd Feeding of granular materials capable of flowing
US3357798A (en) * 1962-11-22 1967-12-12 Takara Koki Kabushiki Kaisha Centrifugal apparatus for obtaining chemical reactions
US3556172A (en) * 1968-06-20 1971-01-19 Int Machinery Corp Method of and apparatus for filling containers
US4566584A (en) * 1984-10-29 1986-01-28 Hi-Speed Checkweigher Co., Inc. Weighing conveyor
DE3538474A1 (en) * 1984-10-29 1986-05-07 Hi-Speed Checkweigher Co., Inc., Ithaca, N.Y. DEVICE FOR TRANSPORTING AND WEIGHING OR CONTROLLING WEIGHTS OF OBJECTS

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