US 3142348 A
Description (OCR text may contain errors)
July 28, 1964 K. G. LYTTON FIBER FEEDING APPARATUS 3 Sheets-Sheet 2 Filed June 14, 1961 1527/2715 fllmafl BY W ATTORNEYS July 28, 1964 K. G. LYTTON FIBER FEEDING APPARATUS 3 Sheets-Sheet 3 Filed June 14, 1961 INVENTOR 115M272? Zrrrozv United States Patent 3,142,348 FIBER FEEDING APPARATUS Kenneth G. Lytton, Gastonia, N.C., assignor to Fiber Controls Corporation, Gastonia, N.C., a corporation of North Caroiina Filed June 14, 1961, Ser. No. 117,126 8 Claims. ((31. 177-114) This invention relates to textiles and, more particularly to improvements in fiber feeding and opening equipment. More especially, this invention relates to improvements in the fiber opening and feeding equipment disclosed in my copending application Serial No. 857,140, filed December 3, 1959, now Patent 2,995,783.
The equipment disclosed in that application, which is of the weighing feed type, includes a fiber feeder having a large hopper from which fibers are removed by an upwardly inclined spike apron. Adjacent and in close proximity to the upper portion of the apron is an oscillating Sargent comb which removes the bulk of the fibers from the apron spikes and permits the balance to be carried upwardly over the upper end of the apron. Rotating in close adjacency to the upper end of the apron is a doffer which strips the small tufts of the fibers from the spike apron and allows the removed fiber tufts to fall downwardly through a discharge opening.
Disposed beneath the feeder discharge opening, to receive fibers therefrom, is a weigh pan suspended from a scale beam and provided with bottom dumping doors. Appropriate controls are provided to stop the drive of the spike apron when a predetermined weight of fibers has been received in the pan, i.e., when the feeder has weighed out, and to restart the apron when the fibers have been dumped from the pan. Disposed beneath the weigh pan is an endless conveyor which receives batches of fibers discharged from the weigh pan and feeds them into a card or the like. Preferably, this feeding conveyor is driven by or with the card in synchronism therewith. According to the aforedescribed application, the dumping doors of the weigh pan are cyclically opened to discharge its batch of fibers, of a predetermined weight upon the feeding apron by mechanism driven by or in synchronism with the feeding apron. Of course, the batch weight and the feed rate of the feeder are adjusted and correlated with the dumping cycle so that the feeder will feed out the predeteirnined weight of fibers into the weigh pan in a period of time less than the interval between openings of the weigh pan dumping doors by the cyclic mechanism.
Desirably the feeder feeds fibers at a relatively slow rate. A slow feed rate improves weighing accuracy because a smaller quantity of fibers is falling through the air into the weigh pan when the spike apron stops. Additionally, a slow rate of movement of the spike apron, coupled with a relatively high rate of movement of the Sargent comb and of the doffer, improves the opening of the fibers by the feeder. Of course, a slow rate of movement of the spike apron results in less wear of the apron, the rollers over which it is trained, and the bearings for the rollers.
In actual practice, however, a fiber feeder of the aforedescribed type feeds fibers at a slower actual rate when its hopper is nearly empty than when its hopper is full of fibers. Consequently, when the hopper of the feeder becomes nearly empty its feeding rate may be decreased to such an extent that the predetermined batch weight of fibers will not be fed into the weigh pan within the normal feeding cycle between weigh pan dumps. The result will be a light dump or, more usually, a series of increasingly light dumps. The invention disclosed in the aforementioned application attempts to overcome such difiiculty by a safety arrangement wherein the fiber feeder is operated automatically to feed fibers at a greater feed rate, i.e., the speed of the spike apron is increased, during a last fractional part of each interval between pan dumps in the event that the weigh pan does not receive the predetermined weight of fibers at the beginning of such fractional part. Thus, when the feeder begins to feed at a slower rate because the supply of fibers in the hopper is getting low, the feed rate is automatically increased during the last fractional part of each feeding cycle in order to avoid light dumps. The application also discloses signalling means, which is actuated whenever the feeder operates at the increased feed rate, to indicate to an attendant that more fibers are needed in the hopper.
While the aforedescribed equipment has been operated successfully, it posses disadvantages. Thus, once the feed rate of the feeder decreases, because the supply of fibers in the hopper is low, to such an extent that the feeder is shifted into high speed, i.e., the spike apron speed is increased, during a last fractional part of each feeding cycle, such increased speed of operation during only such last fractional part of each operating cycle may be insufficient to provide the necessary safety factor to avoid light dumps, i.e., will not feed sufiicient fibers during each feeding cycle. Under those circumstances, the time at which the feeder weighs out during each feeding cycle may rapidly and progressively approach the end of each cycle, and very quickly reach the point Where the feeder will not weigh out at the end of each cycle. Until the situation is corrected, the result will be a succession of socalled light batches or light weights. If, for example, the feeder is set to weigh 16 ounces in each batch, a light batch of only 15 ounces may be tolerated. On the other hand, a succession of IS-ounce batches cannot be tolerated, particularly if such succession rather rapidly decreases from 15 ounces to 14, to 13 and even to 12-ounce batches.
Accordingly, it is an object of this invention to provide an improved safety arrangement for assuring against light dumps, of a cyclically discharging textile fiber weighing feed, occasioned by a low supply of fibers in its hopper.
It is another object of this invention to provide an improved safety arrangement of the type under consideration which automatically increases the feed rate of a cylically discharging weighing feed at any time that the feed has not weighed out at the time when it discharges, and which maintains such increased feed rate until the mechanism is reset by an attendant.
It is another object of this invention to provide a'weighing feed of the type described in the above object with signalling means to indicate when the feed rate has been automatically increased.
Other objects and advantages of the invention will become apparent from the following description and accompanying drawings in which:
FIGURE 1 is a perspective View of apparatus embodying this invention for feeding a textile card.
FIGURE 2 is an enlarged fragmentary side view of a portion of the machine shown in FIGURE 1, and with a side door of the machine removed to illustrate interior parts.
FIGURE 3 is an enlarged fragmentary sectional view taken substantialy on line 33 of FIGURE 2.
FIGURE 4 is an enlarged fragmentary sectional view taken substantially on line 4-4 of FIGURE 2.
FIGURE 5 is a diagrammatic view showing the controls of the machine shown in FIGURE 1 and illustrating the use thereof in feeding a textile card.
FIGURE 6 is a fragmentary view of a portion of FIG. 5 showing a slight modification of the control system.
FIGURE 7 is a fragmentary View of a portion of FIG- URE 5 showing a further modification of the control system.
Referring now to FIGURES l, 2 and 5 of the drawings, there is shown a fiber processing and feeding machine of a type well-known in the art. The machine includes a housing having side and rear walls 12 and 14 partly delining a hopper 16, best shown in FIGURE 5, provided with an opening 18 adjacent its top through which fibers are deposited, usually by hand. At the bottom of the hopper 16 is an endless conveyor 20 which includes front and rear rollers 22 and 24. The conveyor 24 moves the fibers forwardly into engagement with an upwardly and forwardly extending spiked apron 26 trained over upper and lower rollers 28 and 3h. The apron 26 picks up the fibers and moves then upwardly out of the hopper 16. Adjacent the top of the apron 26 is a Sargent comb 32 which oscillates in close proximity to the spiked apron to strip therefrom surplus fibers so that upwardly beyond the comb the apron carries a web or mat of fibers of generally uniform thickness. In front of the upper roller 23 of the apron 26 is a rotating dolfer 34 which strips the fibers from the apron and allows them to fall downwardly, in opened condition, through a discharge opening 36 beneath the doffer.
Disposed beneath the discharge opening 36 of the machine 1th is a weighing receptacle or scale pan 33 that is generally rectangular in plan view. The pan 38 is suspended, by straps 40, from the ends of the parallel arms 42 of a yoke-like scale beam 44 which straddles the discharge opening 36. The beam 44 is pivotally mounted on fulcrums or antifriction bearings 46 on the outer sides of the side walls 12 of the machine It). Extending rearwardly of the beam fulcrums 46 is a beam counterbalance arm 48 having a threaded extension 50. Adjustable along the extension 5d is a large tubular counterweight 52 which can be maintained in a fixed position of adjustment by stop nuts 54 engaged with the opposite ends thereof. Between the counterweight 52 and the fulcrum point 46 of the beam 44 is a smaller counterweight 56 slidable along the beam and cooperating with an indicia scale 58 thereon. The counterweight 56 constitutes a Vernier adjustment and preferably the scale 58 is provided with indicia corresponding to /2 ounce weight adjustments.
Secured to the side 12 of the machine housing over the outer end of a beam arm 42 is a U-shaped permanent magnet 6t? positioned to attract and pull the end of the arm 42 upwardly, such end being formed of a magnetic material (as shown) or having a plate of such material secured thereto. Guided for vertical movement between the magnet arms is a stop 62 adapted to project below the lower ends of the magnet arms for varying the spacing between the scale arm 42 and the magnet 60. The stop 62 is vertically adjustable by means of a screw 64 which swivelly carries the stop and threadedly engages a plate 66 secured to the side 12 of the machine housing.
From this construction it will be seen that the nearer the beam arm 42 to the magnet 60, the greater the attractive force exerted by the magnet on the beam arm, and vice versa. Preferably, a scale (not shown) is associated wiht the magnet 64) and the stop 62 and provided with indicia for measuring, in ounces, the attractive force between the magnet and the beam arm 42 when the latter is engage with the stop. In actual practice, the stop 62 is adjusted so that such attractive force is about 4 ounces. The sliding Vernier counterweight 56 is then set at zero on the scale 58 and the counterweight 52 is adjusted so that the scale beam 44 is substantially in balance when the beam arm 42 is engaged with the stop 62. The sliding Vernier counterweight 56 can then be adjusted along the scale 58 so that a predetermined Weight in the pan 33 will pull the arm 42 away from the magnet 64 and allow the pan to drop downwardly to the extent permitted by an adjustable stop 68 mounted on the side of machine housing 12 in position to be engaged by the counterweight 52.
By reason of the magnet 64 the action of the beam arm 42 in pulling away therefrom will be very rapid,
i almost a snap action, so that the entire weighing mechanism is very accurate.
The bottom of the scale pan 38 is formed by a pair of dumping doors 7t) hinged to the lower edges of the longitudinal side walls of the pan so that the doors may be swung downwardly to dump the contents of the pan. Secured in an upright position on the outer side of an end wall of the pan 3? is the cylinder of a singleacting reciprocating fluid motor 72 arranged to extend its piston rod '74 when fluid pressure is supplied to the cylinder through a hose 76 from any suitable source. A link 78 is pivotally connected to a crank arm St? on each door and to the corresponding end of a cross bar 82 on the end of the piston rod 74 of the motor 72. The arrangement is such that when the piston rod 74 is extended the dumping doors 7t) are held shut, but when the piston rod is retracted the dumping doors open. The supply and exhaust of fiuid under pressure to the motor 72 may be controlled by a two-way solenoid valve 84 (FIGURE 5) connected into the hose 76, or into a supply conduit (not shown) leading thereto. The arrangement is such that when the valve 84 is deenergized the motor 72 is supplied with pressure fluid and the doors 70 are held shut, and when the valve is energized the supply is cut off and the motor is exhausted so that the doors fall open. An appropriate spring (not shown) may be employed to constantly urge the doors 759 to open, and thus hasten their opening on relief of pressure in the motor 72.
The foregoing weighing and dumping mechanisms are similar in many respects to those shown in the copending application of Lytton et al. Serial No. 348,406.
The machine 1% is driven by a conventional electric motor 86 that may be secured to the housing front wall 83 and has a belt drive 90 to one end of the doffer shaft 92. The Sargent comb 32 is driven by a crank arm on an eccentric arrangement (not shown) mounted direetly on the same end of the doffer shaft 92. The spiked apron 26, and also the hopper bottom conveyor 20 which is driven by a belt 94 from the shaft of the lower apron roller 36, are driven by a variable speed drive between the other end of the doifer shaft 92 and an end of the shaft of the upper roller 28 of the spiked apron. This variable speed drive includes a variable effective diameter sheave 96 fixed to the end of the doifer shaft 92. The sheave 96, as is Well-known in the art, includes two halves or parts 98 having inclined opposed edges 1% to form the side walls of a circumferential groove for receiving a V-belt 1632, as shown in FIGURE 4. The two parts 98 of the sheave 96 are constantly urged toward each other by a spring 104 so as to increase the effective diameter of the sheave as respects the belt 102. It will be seen, however, that when a sufiicient pulling force is exerted on the belt 102, it will spread the parts 98 to reduce the effective diameter of the sheave 96. When the effective diameter of the sheave 96 is so reduced the belt 102 will drive another part at a lower speed than when the effective diameter of the sheave is increased.
Rotatably mounted on the end of the shaft of the upper roller 28 for the spiked apron 26 is a gear housing 166 enclosing a gear 1% fixed on the shaft, as shown in FIGURE 3. A pinion lit meshing with the gear M38, is journalled in the side walls of the housing 1% and has a projecting stub shaft carrying a sheave 112 over which the belt 162 is trained to drive the spiked apron 26. A single-acting reciprocating fluid motor 114, adapted to retract its piston rod 116 on the supply of fluid pressure to its cylinder through a hose 118 from a suitable source, has the closed end of its cylinder connected by a link 12th to the gear housing 1% at a location adjacent the pinion gear lid. The end of the piston rod 116 of the motor 114 is pivotally connected to a lever 122 which has one end thereof pivotally connected, at 124,-to the side 12 of the machine housing for limited angular adjustment. The other end of the lever 122 carries a spring-pressed pin 126 adapted to project, when aligned therewith, into any one of an arcuately-arranged series of recesses or holes 128 in a quadrant-plate 130 fixed to the side wall 12 of the machine housing.
From the foregoing construction it will be seen that when fluid pressure is supplied to the motor 114 and the pin 126 is in a hole 128, the rod 116 will retract and swing the gear housing 106 in a direction to increase the distance between the sheaves 96 and 112, thus spreading the parts 98 of the sheave 96 and reducing the driven speed of the sheave 112. When the motor is exhausted the piston rod 116 extends, because of the extending force exerted thereon by the belt 102, and thus allows the parts 98 of the sheave 96 to move toward each other and increase the driven speed of the sheave 112 (as shown in dotted lines in FIGURE 2). The speed of the sheave 112, and consequently the spiked apron 26 and the conveyor 26, can also be adjusted, in either the pressurized or exhausted condition of the motor 114, by manually changing the angular position of the lever 122 and relocking it in place by engaging the pin 26 in a selected one of the holes 128.
The supply and exhaust of pressure fluid to and from the motor 114 is controlled by a two-way solenoid valve 132 (FIGURE 5) connected into the hose 118 or into a supply conduit (not shown) leading thereto. The valve 132 is arranged so that when it is de-energized, pressure fluid is supplied to the motor 114 thus driving the machine at slow speed, and when the valve 132 is energized, the supply of fluid pressure is shut off and the motor 114 exhausted thus driving the machine at high speed. Preferably, the weighing and speed change mechanisms are enclosed in a compartment on the side of the machine 10 which is closed by a door 134.
Beneath the weigh pan 38 the sides 12 of the machine housing are extended, as at 1315, to form the sides of a chute 136 adapted to receive batches of fibers dumped from the pan. The chute 136 is generally rectangular in horizontal section, approaching the plan of configuration and size of the weigh pan 38, and has downwardly and forwardly inclined flat front and rear walls 138 and 140. The inclination of the chute 136 may be of the order of 40 to the vertical.
At the bottom of the chute 136 is an endless conveyor having a horizontal belt 142 trained over front and rear rollers 144 and 146 journalled in the front extensions 135 of the sides 12 of the machine housing. The bottom or rear wall 140 of the chute 136 depends into close proximity of the conveyor belt 142, as shown in FIGURE 5, While the front extensions 135 depend therebelow. Adjacent and above the front roller 144 of the conveyor 142 is a press roll 148 adapted to ride on fibers being carried forwardly out of the bottom of the chute 136 on the belt 142. The press roll 148 is maintained in position by end stub shafts received in vertical guideway notches 150 in the front extensions 135 of the sides 12 of the machine housing. The upper or front wall 138 of the chute 136 depends into close adjacency with the rear side of the press roll 148, so that the latter essentially forms the lower portion of the front wall of the chute. It will be seen that as the upper reach of the conveyor belt 142 moves forwardly, it will feed fibers out of the chute in a relatively thin flat web or stream. In some instances it is desirable to provide the press roll 148 with an arrangement (not shown) for driving the same at the same peripheral speed as the linear speedof the conveyor belt in order to assure the proper feeding of fibers out of the chute in a uniform web or stream.
In use of the apparatus, the front roller 144 of the conveyor 142 is positioned closely adjacent the feed rolls 152 of a card 154, only a portion of which is illustrated diagrammatically in FIGURE 5. The card feed rolls 152 receive the web emerging from beneath the press roll 148 and feed it to the conventional licker-in 156 of the card. The conveyor 142 is driven by or in synchronism with the card 154 by means of an appropriate drive train 157 (not shown in detail) between the card and the stub shaft of one of the conveyor rollers 144 or 146.
Referring now to FIGURE 5 of the drawings, the motor 86 is supplied with power, from any appropriate source of three-phase power, by the conductors 158 which have three sets of normally-open contacts of a motor control relay 160 interposed therein. The relay is controlled by a circuit which includes the energizing coil of the relay 160, a normally-closed cam operated switch 162, a
weigh switch 164, and a manually-operable switch 166,-
all connected in series across an appropriate source of power, e.g., a transformer 168, by conductors 170, 172, 174, 176, 178, and 180. The weigh switch 164 may be in the form of a conventional microswitch mounted on the side 12 of the machine housing above the arm 42 of the scale beam 44. The arrangement is such that when the arm 42 of the beam 44 is engaged with the stop 62 associated with the magnet 60, the weigh switch 164 is closed, but when any selected predetermined weight of fibers has been received in the weigh pan 38 and pulls the arm 42 away from the stop 62, the switch 164 is open.
From the foregoing arrangement it will be seen that when the switch 166 is closed and the weigh pan 38 is empty, the circuit which includes the energizing coil of the relay 160 will be closed so that the normally-open contacts of the relay in series with the conductors 158 will close, and the motor 86 will drive the machine 10 to feed fibers into the weigh pan 38. When the latter receives its predetermined weight of fibers the weigh switch 164 will open and the relay 160 will be de-energized, thus stopping the motor 86 and further feeding the fibers into the weigh pan.
Preferably, a normally open cut-oif door 184 is mounted on a horizontal shaft 186 journalled in the side walls 12 of the machine housing immediately to the rear of the front wall 88 of the machine and above the discharge opening 36. The cylinder of a single acting reciprocatirrg fluid motor 188 is pivotally mounted, as at 190, to the side wall 12 of the machine housing, as shown in FIG- URE 2. The end of the piston rod 192 of the motor 188 is pivotally connected to a crank arm 194 on the end of the door shaft 186. The arrangement is such that when the piston rod 192 is extended, the door 184 lies substantially flush against the front wall 88 of the machine housing, but when the rod 192 is retracted, as by the supply of fluid pressure to the motor 188, via a hose or conduit 196, the door 184 is swung into a position to substantially block the discharge opening 36 of the machine 10. The motor 188 is controlled by a two-way solenoid valve 198 connected into the conduit 196. When the valve 198 is energized, the supply of fluid pressure to the motor 188 is interrupted and the latter is vented to atmosphere. When the valve 198 is de-energized, the motor is supplied with fluid under pressure. The energizing coil of the valve 198 is connected in parallel with the energizing coil of the relay 160 via conductors 197 and 199. Consequently, it will be seen that when the relay 168 is de-energized on the opening of the weigh switch 164, so as to stop the motor 86, the door 184 closes to thereby quickly interrupt t h e further feeding of any fibers into the weigh pan 38 and thus insure improved weighing accuracy.
The apparatus described thus far is substantially the same as that described in my aforementioned copending application Serial No. 857,140.
The weigh pan 38 is dumped periodically by operation of a earn 206) driven in synchronism with the conveyor 142, as by being mounted on a shaft 202 driven directly by the rear roller 146 of the conveyor. The energizing circuit of the dumping solenoid valve 84 includes a normally-open switch 204 adapted ot be closed for a brief interval by the cam during every revolution thereof. The switches 284 and 166, and the coil of the solenoid valve 84 are connected in series and supplied with power from 7 the transformer 168 via conductors 2%, 2%, 214), 1'76, 178, and 18th.
The rate of feeding of fibers by the machine it is correlated with the dumping cycle effected by the cam 2439 so that the desired predetermined weight of fibers will be fed mm the weigh pan 38 well in advance of the time that the pan is dumped, for example, during at least the first of the interval between dumps, so that during the remaining A1 of the cycle time the further feeding of fibers will cease because of the opening of the weigh switch 164, as aforedescribed. At the end of the cycle the conveyor driven cam 21% will close the switch 2%, thus causing the batch of fibers to be dumped into the chute 136. The predetermined weight of fibers thus periodically dumped into the chute 136 desirably is correlated with the amount of fibers being withdrawn from the chute by the conveyor 142; in such a manner that the average rate of feed into the chute equals the average rate of withdrawal of fibers therefrom.
A second earn 212 on the shaft 2% is adapted to cyclically open the normally closed switch 162 in the energizing circuit for the relay 160. The cam 212 opens the switch 162 at substantially'the same moment that the cam 29% closes the dumping switch 294, but maintains the switch 162 open for a short interval of time after the weigh pan 38 has been dumped before allowing the switch 162 to close. This interval of time during which the switch 162 is open is long enough to permit the weigh pan 33 to rise, the beam arm 42 to come to rest against the stop 62, and the dumping doors 7% to close before the motor 85 re starts to drive the machine 10 to again feed fibers into the weigh pan.
Connected in parallel with the energizing coil of the dumping solenoid valve 84, via the conductors 2%, 21d and 215, is a fourth set of normally open contacts of the motor control relay 16%) and the energizing coil of a safety relay 218 having two sets of normally open contacts. The relay 213 is provided with a latch arm 22% engageable with a movable keeper 222 on energization of the relay, so that the two sets of normally open contacts will be maintained closed, even though the coil of the relay 218 is de-energized, until the keeper is moved out of engagement with the latch arm. The keeper 222 can be moved out of engagement with the latch arm 22% manually, but it is pre erred to accomplish such movement electrically by means of an appropriate solenoid 224 mechanically connected to the keeper and having its energizing coil sup plied with power from the transformer 163, via the conductors 226 and 228, a normally-open manually-operable switch 230, preferably of the push button type, conductors 232, 176, 178 and 189. It will be seen that once the relay 218 has been energized, even though momentarily, its contacts will close and remain closed until the switch 23 is closed to release the keeper 222 from the latch arm 220 and permit the contacts of the relay 218 to open.
The energizing circuit for the solenoid valve 132 which controls the speed change mechanism of the machine It) includes the switch 166 and a set of the normally open contacts of the relay 218, all connected in series with the transformer 168 source of power by conductors 180, 178, 176, 234, 236, 238 and 2%. From this arrangement it will be seen that if the weigh pan 38 has not received its predetermined weight of fibers, so that the weigh switch 164 is still closed, and the motor control relay 170 is still energized, at the time that the dumping cam 290 closes the switch 204 to energize the dumping solenoid valve 84, the fourth set of normally open contacts of the relay 17d will be closed so that the relay 218 will thus become energized. Energization of the relay 2.18 closes the energizing circuit for the solenoid valve 132 to thus cause the speed change mechanism to change the speed of the spike apron 26 from its adjusted set speed to a higher speed. Because the relay 218 is of the latching type which must be reset, the apron will continue to be operated at such higher speed, during each succeeding feeding cycle of the ma- 8 chine 10, until the relay 2118 is reset as, for example, by closing the switch 231 as aforedescribed.
Although the above described arrangement may result in one light dump before the delivery rate of the machine 10 is increased, by speeding up the spike apron drive, the amount by which the light dump will be underweight normally will be insignificant. When the supply of fibers in the hopper of the machine 10 starts to become low, the actual feed rate of the machine will decrease relatively slowly so that the actual instant during the dumping cycle at which the machine weighs out, will only slowly approach the end of each feeding cycle. Thus, for example, if the machine is set to weigh out 16-ounce batches of fibers and the supply of fibers in the hopper starts to get low, the first time that the machine fails to weigh out at the end of the feeding cycle, the resulting light dump may still be of the order of 15 or even 15 /2 ounces of fibers.
Of course, such light dump will result in speeding up the drive for the apron 26 with a consequent increase in the actual feed rate of fibers by the machine it). Since the spike apron drive will remain at such higher speed during the entire time interval between dumps in each succeeding cycle of operation, it will be seen that the actual feed rate of the machine will be increased considerably so as to assure the maintenance of full weight dumps fora great many succeeding cycles of operation.
Preferably, a signal, such as a lamp 242, is connected in series into an energizing circuit which includes the conductors 244 and 246, a set of normally-open contacts of the relay 211.8, conductors 234 and 176, switch 166, conductor 178, the transformer 168, and conductor 1869. Thus, whenever the apron drive of the machine it) has been shifted to a higher speed by energization of the relay 218, the lamp 242 is lighted to indicate to an attendant that additional fibers are needed in the hopper of the machine. Of course, the lamp could be replaced or augmented by an audible signalling means (not shown).
A third cam 248 on the shaft 2% is adapted to periodically close a normally-open switch 259 during a last fractional part, e.g., A, of the time interval between dumping operations. The lamp 242 is connected into an energizing circuit which includes the conductors 24-4, 246, and 252, the switch 250, conductors 254 and 174, the weigh switch 164, conductor 176, switch 166, conductor 178, the transformer 168, and conductor 180. From this arrangement it will be seen that if the weigh pan 38 has not received its predetermined weight of fibers, so that the weigh switch 164 is still closed, at the time that the cam 243 closes the switch 250, the lamp 242 will be lighted to indicate to the operator that the supply of fibers in the hopper is starting to get low. Of course, when the machine Weighs out, the lamp 242 will be turned off. Thus, an attendant will have a preliminary indication that the supply of fibers is running low even before the machine it actually shifts the apron driven into a higher speed to increase the actual delivery rate of fibers from the machine. The machine 10 normally will be adjusted to weigh out before the cam 248 closes the switch 250 so that the lamp 242 will not be lighted.
In some installations, the hopper of the feeder 10 may be filled automatically, as by a pneumatic conveying system terminating in a condenser, instead of by hand. In such an arrangement (not shown) the filling of the hopper frequently is controlled by a mechanism responsive to the quantity of fibers in the hopper. Such a mechanism (not shown) will effect delivery of fibers into the hopper only when the supply therein falls below a predetermined level and will shut off the delivery of fibers to the hopper only when the supply therein exceeds a predetermined level. In such an arrangement the relay 218 can be arranged to be reset automatically instead of manually. Thus, for example, referring to FIGURE 6 of the drawings, it will be seen that the relay-resetting switch 23% can be replaced by the normally open contacts of a time delay relay 2.56 which delays closing its contacts for a predetermined period of time following energization of its coil. The coil of the relay 256 may be connected in parallel with the lamp 242, as by conductors 258, 260, and 246. Consequently, whenever the drive for the apron 26 automatically is increased because the supply of fibers in the hopper becomes low, the time delay relay 256 is energized. The delay time of the relay 256 is adjusted so that its contacts Will close and thus reset the relay 218, so that the drive for the apron will be shifted back to its normal rate, only after a period of time sufiicient for the supply of fibers in the hopper to be automatically increased to a point wherein the high speed drive of the apron 26 is unnecessary in order to avoid light dumps.
As will be readily understood in the art, the time delay relay 256 could be replaced by an electric counting mechanism 262 (FIGURE 7) arranged to close the normallyopen contacts of the switch 230 for energizing the solenoid 224 only after a predetermined number of dumps of the weigh pan 38 had taken place after the drive for the apron 26 had been shifted to the higher speed. The mechanism 262 is connected in parallel with the dumping solenoid valve 84 via conductors 210, 264-, 266, a third set of normally open contacts of the relay 218, and conductor 268. Such type of switch-closing counting mechanism 262 is automatically reset, when de-energized, to reopen the contacts of the switch 230.
The relay-resetting switch 230 also could be arranged to be governed by the mechanism which automatically controls the delivery of fibers to the hopper of the feeder 10. Such mechanism usually includes a fiber level sensor in the form of a movable plate or arm 270 (FIGURE Thus, for example, the switch 230 could be replaced by a limit switch 230' operated by the level sensor 270 to open its contacts whenever the fibers in the hopper fall below a predetermined level and to close its contacts when the fibers exceed such level.
It thus will be seen that the objects of this invention have been fully and efiectively accomplished. It will be realized, however, that the foregoing specific embodiment has been shown and described only for the purpose of illustrating the principles of this invention and is subject to extensive change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.
1. Fiber feeding and weighing apparatus comprising: a fiber processing machine having a hopper for fibers, a spike apron extending upwardly out of said hopper for re moving fibers therefrom, a dofi'er for the upper end of said apron, and motor means including speed change means for driving said apron; weighing mechanism including a weigh pan positioned to receive fibers dotted from said apron; control means for said motor means responsive to a predetermined weight of fibers in said pan for stopping the drive of said apron; means associated with said pan for discharging fibers therefrom; cyclic means for actuating said discharge means; and resettable control means for said speed change means associated with said motor control means for automatically changing the drive of said apron from a low to a high speed, and for maintaining said drive at high speed in succeeding cycles in the event that the predetermined weight or" fibers is not in said pan at a time when said cyclic means actuates said discharge means.
2. The structure defined in claim 1 in which the control means for the speed change means is manually resettable.
3. The structure defined in claim 1 in which the control means for the speed change means includes time delay mechanism for maintaining the drive at high speed for a predetermined time interval and then changing the drive back to low speed.
4. The structure defined in claim 1 in which the control means for the speed change means also is associated with the cyclic means for maintaining the drive at high speed for a predetermined number of actuations of the discharge means and then changing the drive back to low speed.
5. The structure defined in claim 1 in which the control means for the speed change means includes a latching relay.
6. The structure defined in claim 1 including signalling means, and control means for said signalling means associated with said control means for said speed change means for actuating said signalling means when the apron drive is at high speed.
7. The structure defined in claim 1 in which the speed change means includes manually operable means for changing the speed of the drive of the apron independently of the control means for the speed change means.
8. The structure defined in claim 1 in which the control means for the speed change means includes means for sensing the level of fibers in the hopper and for maintaining the drive at high speed so long as the fibers are below a predetermined level and for changing the drive back to low speed when the fibers exceed said predetermined level.
References Cited in the file of this patent UNITED STATES PATENTS