US 3161124 A
Description (OCR text may contain errors)
1954 N. E. STRGMBERG 3, 61,
MEANS FOR COMPRESSING FLUEF'Y PAPER PULP TO THE SHAPE OF BALES Filed Dec. 5, 1962 3 Sheets-Sheet 1 SCALE LJ ]T/ME ozmv FIG 1 r f ss %J LW r Dec. 15, 1964 N. E. STRC'JMBERG 3,161,124
MEANS FOR COMPRESSING FLUF'FY PAPER PULP TO THE SHAPE OF BALES Filed Dec. 3, 1962 5 Sheets-Sheet 2 FIG. 2. 4
L U I' 25 22 75 76 78 77 //9 (P 04: (7/75 l lr// 0 m M a)! Dec. 15, 1964 N, E. STRGMBERG MEANS FOR COMPRESSING FLUFFY PAPER PULP TO THE SHAPE OF BALES 3 Sheets-Sheet 3 Filed Dec. 5, 1962 United States Patent In the manufacture of bales of paper pulp it was hitherto usual practice to compress sheets cut from a continuous web of paper pulp to form bales of a size suitable for transportation'and pass a wire or iron band around each bale to hold same together.
In order to render the manufacture of the bales, and
more particularly the drying V of the paper pulp, more simple and cheap and reduce the costs of erection as well,
a novel system of operation has been developed and practiced in the recent years.
According to said system the Web or paper pulp is first V freed from water in the previously usual way down to a degree of dryness of about 45%. By means of special graters the web of paper pulp is then broken up into wads which are carried away and dried by means of hot air blowers down to a degree of dryness of about 85%. The product thus obtained is generally known as fluffy pulp.
The transformation of the fiuffy pulp into bales of a predetermined weight and volume, however, is concomitant with great difficulties owing to the extraordinarily large volume the amount of flutfy pulp required to constitute a bale occupies in its natural state. In order to form a bale which from transportation point of view presents an appropriate homogeneity, the volume of said amount of fiuffy pulp must be reduced by about forty times which requires the use of compressing units having accordingly large compressing chambers. The'consistency of the fluffy pulp renders the collection and the dosage to the compressing unit of the correct amount of pulp for each bale more difiicult owing to the fact that pockets having restricted outlets cannot be used without the use ofmechanical feeding means because of the tendency of the pulp towards hanging and formation of arches.
The weight of the finished bales should, as far as possible, be constant, since all sale of paper pulp is based upon the nominal bale weight. In existing plants for the manufacture of fiuify paper pulp theproblem of performing the dosage prior to the compressing operation could not be solved satisfactorily. As a result a manual adjustment of the weight of the bales, as by means of an axe or similar implement, had to be done in certain cases subsequent to the compressing operation. In such cases the dosage is usually effected during a given period of time by means of a time, relay. Thus, in the event of capacity variations of the plant prior to the performance of the dosage, the weight of the bale will also vary.
An object of the invention is to permit the collection of a predetermined amount of fluffy pulp and the transformation of said amount to the shape of a bale with theuse of a press having a compression chamber of essentially reduced dimensions as compared with the original volume of the amount of fluffy pulp collected for the formation of a bale.
Another object of the invention is to provide means for controlling the amount of pulp to be supplied to the press, which operates independently of variations of the capacity of the preceding part of the plant to produce bales of a constant weight.
A feature of the invention is that the compression of the fluffy pulp to the shape of a bale, by means of a hydraulic or similar press, is preceded by one or more precompression stages during the feeding of the pulp to 1 the press.
Another feature of the inventioninvolves that a priice mary precompression stage is carried out in connection with the transfer of the fluffy pulp from a drying plant to a weighing device included in the feeding mechanism of the press which serves to determine and collect the quantity by weight of flulfy pulp required to form a bale, while a second precompression stage is carried out in connection with the transfer of the quantity of fluffy pulp thus determined from said weighing device to the press.
In an apparatus for carrying the invention into effect, a drying plant for fluify paper pulp, aweighing device for dosing the quantity of fluffy pulp required for each individual bale, and a hydraulic or similar press are arranged as a coherent system the various main elements of which are interconnected by means of screw conveyors.
The features of said main elements will appear from the description hereinafter to follow with reference to the accompanying drawings and will be more definitely pointed out in the annexed claims.
In the drawings,
FIG. 1 is a partially diagrammatic side elevation of the final stage of the drying plant and the upper portion of the weighing device together with the connection therebetween.
FIG. 2 is a part sectional side elevation of the press in its position ready for starting a compressing operation, and the remaining portion of the weighing device.
FIG. 3 is a vertical section of the press and associated members in a position during the feeding out of a completely compressed bale.
FIG. 4 is a part sectional vertical elevation of the press ready for starting another pressing operation after the delivery of a finished bale.
With reference to FIG. 1, the numeral 1 designates the lower portion of a set of cyclones, in which fiuify paper pulp undergoes the final stage of a drying procedure which may be carried out in well-known manner by wellknown means. In said cyclones the dried pulp is separated'from thehot airused in effecting the drying. The cyclones open each at its bottom end into a tubular container 2 serving to collect the fluffy pulp dried in the respective cyclone. Said containers 2 open at their bottom ends into a horizontal screw conveyor housing 3 containing a pair of screw conveyors 3a for feeding the pulp in the direction of the arrow A to a point above the receiving container 4 of a weighing device Said weighing device is only indicated in the drawing, represented as it is by a pair of levers 5, since it may be of any appropriate structure known per se. The weighing device as broadly diagrammatically shown in dashed lines in FIG. 1 of the drawing is assumed to act so that upon the supply to the container 4 of a quantity of fluffy pulp designed to form a bale the weighing device will make a deviation which effects the opening of two flaps 6 serving as the movable bottom of the weighing container 4, thereby allowing the quantity of pulp supplied to the container 4 to drop down in an underlying container hereinafter referred to as collecting container.
In order to adjust the degree of filling of the container 4 towards the end of the filling period means (not shown) may be provided adapted under the control of the weighing device to stop the operation of one of the screw conveyors 3a in' the housing 3, whereas the speed of the other screw conveyor is reduced, as for instance, down to one third of its normal value by means of a two-speed motor or by other appropriate means, before a full quantity by weight is collected in the weighing container 4. In this way a very exact determination of the weight of the pulp designed to form a bale may be secured.
Due to the action of the cyclones 1 a pressure above atmospheric will unavoidably appear in the containers 2. In certain cases this pressure will be pulsatory. By arranging so that the housing 3 is permanently filled with pulp, the pulses of said pressure may be prevented from interfering with the weighing result.
In order under all conditions to be sure that no pressure above atmospheric may appear in the weighing container 4 at the supply of pulp thereto, a ventilating pipe 7 leading to the atmosphere is provided at the delivery end of the housing 3.
Provided below the container 4, FIG. 1, is a pulp collecting container 8 as a direct continuation of the weighing container 4, see also FIG. 2. The bottom of the container 8 is steeply inclined to one side, viz. to the left in the drawing, FIG. 2, and provided thereabove is a screw conveyor 9, acting to transfer the quantity of pulp collected in the container 8 into the press provided by the side of the container 8. To this end the screw 9 extends through a conical tubular outlet 10 leading to the compression chamber of the vertical press cylinder 11. Reciprocating in said compression chamber is a compression head 12 which performs its compressing action during its downstroke. Said compressing head 12 is carried at the bottom end of the rod 13 of a piston (not shown) reeiprocable up and down in a hydraulic cylinder 14.
The press cylinder 11 is open both at its top end, for receiving the compressing head 12 and the associated piston rod 13, and at its bottom end, for delivering the compressed pulp to a bale mould 15 provided below the press cylinder 11 as a continuation thereof. Said bale mould 15 comprises a frame slidably mounted on a stationary base 16 which forms a pressure resisting bottom of the bale mould 15, when the latter is in its normal position right below the press cylinder.
The bale mould 15 may also be displaced laterally from its position on the base 16, FIG. 2, into a position entirely by the side of the press cylinder, as shown in FIG. 3, and thence back again to its normal position below the press cylinder, as shown in FIG. 4. Said displacement of the mould is effected by means of a hydraulic or other pressure cylinder 17, the piston rod 18 of which is connected to one side of the frame 15. During its displacement the frame 15 is sliding, in part, on the base 16 and, in part, on a pair of parallel rails 19 one of which only is shown in the drawings, since both of them are located in the same horizontal plane. During its displacement the frame is guided by means of a pair of rails 20 parallel with the rails 19 though located on a higher level.
To remove the finished bale from the frame 15 after the latter with the bale therein has been moved to the side of the press, an upper disc 21 and a lower disc 22 are provided vertically above each other and movable vertically to engage the upper and lower surfaces, respectively, of a bale in the frame. The surfaces of said discs facing each other are plane and horizontal and of the same size as the upper and lower surfaces of the bale. The disc 21 has for its object to force the bale downwards out of the bale frame 15, while the disc 22 serves to receive the bale thus forced downwards and support it while moving downwards according as the upper disc is moving downwards. The movements of the discs 21 and 22 are controlled by means of hydraulic or similar power-cylinders 23 and 24, respectively.
By the side of the path as covered by the bale while transferred from the frame 15 to the lower disc 22 a plate 25 is pivotally mounted on a horizontal shaft situated on a level corresponding to that of the lower disc 22 when in its uppermost position ready to receive a bale. The purpose and operation of said swingable plate will be evident from the description of the operation of the press hereinbelow to follow.
The fluffy pulp separated from the hot air following the final drying step in the cyclones 1 passes via the containers 2 to the conveyor screws inside the housing 3 and is fed by said screws to the end of said housing situated above the weighing container 4. Under the control of an impulse emitted by the weighing device a preferred reduction of the rate of feed motion is effected towards the end of said motion with a view to secure the supply to the weighing container 4 of a quantity of fiuffy pulp exactly adjusted to form a bale. When the weighing device records full weight, the feed motion is stopped and the bottom flaps 6 are opened under the control of an impulse as emitted by the weighing device. As soon as the bottom flaps 6 are opened, the quantity of pulp determined by the weighing device is allowed to drop from the container 4 down into the collecting container 8.
Simultaneously with the opening of the bottom flaps 6 a time relay (not shown) starts operating, in order after a predetermined period of time corresponding to the emptying period of the weighing container 4, to emit an impulse for closing the bottom flaps 6. After said closing is completed, the conveyor screws inside the housing 3 again start filling the weighing container 4.
The weighing container 4 having been filled and the pulp therein having been allowed to drop down into the collecting container 8, the pulp collected in container 8 will be transferred to the compressing chamber of the press by the action of the screw 9 which by doing this subjects the pulp being transferred to a certain degree of precompression. The. entire quantity of pulp collected in the container 8 having been thus precompressed and transferred to the compressing chamber inside cylinder 11 the formation of the bale by subjecting the pulp supplied to the press cylinder 11 to the action of the compressing head 12 under the control of a time relay started at the same time that the bottom flaps 6 of the weighing container 4 are opened. After a bale of the desired height or consistency is formed in the frame 15, the compressing action is interrupted and the compressing head 12 restored to its uppermost or normal position. When the compressing head during its upstroke has passed the upper edge of the frame 15 an impulse is given to the hydraulic cylinder 17 to cause its piston rod 18 to move to the left in the drawing, thereby displacing the frame 15 to the side of the press. A flat member 26 projecting horizontally from the upper edge of the frame 15 on the side thereof which during the movement of the piston rod 18 is facing rearwards, may act as a bottom of the compressing chamber according as the frame 15 is displaced to the side. Thus, as soon as the plate 26 covers the entire bottom end of the cylinder 11 the compression of the pulp designed to form the next bale may commence by the head 12 again moving downwards.
After the frame 15 with the bale therein has reached its lateral end position, the bale is removedfrom the frame by means of the disc 21 which is moved down under the action of the power cylinder 23 to force the bale out of the frame.
During the displacement of the frame 1.5 to its position to the side of the press, the lower disc 22 is in its uppermost position ready to support the bale to be then moved downwards according as the upper disc 21 is depressed.
Before the frame 15 with the bale therein is moved to the side of the press cylinder and while the upper disc 21 is still in its uppermost position, the swingable plate 25 i swung upwardly about its horizontal axis through half a revolution in order to place a sheet of wrapping paper upon the lower disc 22, now in its uppermost position, as indicated in FIG. 2, said sheet having for its purpose to cover the lower surface of the bale. The member 25 is then swung back to its outer position shown in FIG. 2.
As soon as the upper disc 21 during its downward movement to force the bale out of the frame 15 reaches the lowermost edge of the frame and the bale is, consequently, free from the frame, the downward movement of disc 21 is immediately stopped and the disc returned to its uppermost, or normal, position. The frame 15 is now free to be restored to its position below the press cylinder 11.
While the" lower" disc 22 with the finished bale resting thereon is in its lowermost position the member 25 is again swung upwardly through half a revolution, this time to place a sheet of wrapping paper on the upper surface of the finished bale, as shown in FIG. 4, to be then immediately restored to its outwardly swung position for receiving another sheet of wrapping paper. The disc 22 with the finished bale may then be restored to its uppermost position, by the action of the power cylinder 24 and the bale transferred, as by means of a pusher of wellknown design, from the disc 22 to a conveyor, not shown.
As a result of the restoration of the frame 15 to its position below the press cylinder 11 the pulp compressed within the cylinder against the temporary bottom 26 thereof, is allowed to expand down into the space of the frame, thereby allowing more pulp to be supplied to the compressing chamber by means of the feeder screw 9.
It is to benoted that the above described structure may be modified in several respects without departing from the principle or scope of the invention. Thus, for instance, more than one feeder screw 9 may be provided for transferring the fluify pulp from the collecting container 8 to the compression chamber. The bale receiving .disc22 may be equipped with wheels for the transportation of the bale to an unloading place.
- 1. A machine for forming bales of a fluffy material by a compressing action comprising a plant for drying the fluffy material by means of a hot gaseous fluid, a weighing device comprising a container and a scale, ,a housing connecting said drying plant with said container, said housing having an outlet for the hot gaseous fluid used in the drying operation, screw conveying means in said housing for transferring at intervals from the drying plant to the container of the Weighing device predetermined quantities of fluffy mass adapted each to form a bale, a container for individually collecting each such quantity as delivered from the weighing device, a bale press, means including a screw conveyor at least for transferring each such quantity to said bale press while subjecting it to a precompression.
2. A machine for forming bales of a flufly material by a compressing action comprising a plant for drying the material by means of a hot gaseous fluid, a weighing device comprising a scale and a weighing container, a housing extending between said drying plant and said container, a screw conveyor in said housing for transferring at intervals predetermined quantities of dried fluffy material from the drying plant to the container while subjecting it to a precompression, said housing having an outlet for the gaseous fluid used in the drying operation,
another container for individually collecting the quantities of fluffy material passing through the Weighing container, a bale press having a substantially vertical compression chamber and an up and down movable plunger therein, a bale mould for communicating wtih said compression chamber during the bale compression period, and means for withdrawing said mould together with a finished bale therein and restoring it to bale forming position after removal of the bale therefrom, and means for removing the finished bale from the bale mould. n
3. A machine in accordance with claim 2 in which the container of the weighing device is provided with a movable bottom capable of being opened under the control of the scale to empty the container when the latter has lowermost portion of the collecting container is connected to the compression chamber of the bale press by means of a laterally inclined outlet, a screw conveyor beingprovided in said outlet for transferring the quantity of fluffy material contained in the collector container to the compression chamber.
n 6. A machine in accordance with claim 2 in which the compression chamber of the bale press is of vertical arrangement and open at its bottom end, the bale mould being of the same inner cross section as that of the compression chamber and settable to a position directly below said chamber so as to form a bottom portion thereof, said bale mould being slida'ble laterally from its position below the compression chamber into a position'outside thereof to allow the withdrawal ofa finished bale therefrom.
, 7. A machine in accordance with claim 6 'in which the 'balemould comprises a frame open upwardly and downwardly, the bale press being provided with a stationary base for supporting said frame during the bale PIfiSS'. ing operation. l V
8. A machine in accordance with claim 7 in which there Q are provided a pair of parallel rails extending from one side of said frame supporting base for supporting the frame during its movements to and from bale pressing position.
9. A machine in accordance with claim 8 in which there are another pair of rails parallel with those mentioned in claim 8 for laterally guiding the frame during= its movements to and from bale pressing position.
1 10. In a machine in accordance with claim 2, and in which the bale mould comprises a frame open upwardly and downwardly, the feature that the means for removing a finished bale fromthe bale mould frame when moved to the side of the bale press comprises an up and down movable member for removing a finished bale from the frame when located vertically therebelow by exerting av downward pressure on the bale, and another likewise up and down movable member for receiving a bale thus removed from the frame.
- 11. In a machine in accordance with claim 10 the vprovision of means for placing sheets of' wrapping material below and above a bale delivered onto said bale receiving member. a
References Cited in the file of'thispatent UNITED STATES PATENTS 594,008 Hanak Nov. 23, 1897 876,553 Hutton et a1. Jan. 14, 1908 2,929,313
Luthman et :al. Mar. 22, 1960 OTHER REFERENCES Paper Trade Journal magazine (p. 2832), March 18, 1957.