US 3518849 A
Description (OCR text may contain errors)
July 7, 1970 w. s. EQGGLESTON 3,
HIDE PROCESSING METHOD AND APPARATUS Filed Nov. 26, 1968 2 Sheets-Sheet 1 F |G 1 (PRIOR ART) F|G 2 INVENTOR. WILLIAM S EGGLEST ON BY 7 f ATTORNEYS y 1970 w. s. EGGLESTON 3, 1
HIDE PROCESSING METHOD AND APPARATUS Filed Nov. 26, 1968 l 2 Sheets-Sheet 2 INVENTOR. WILLIAM S. EGGLEST ON ATTORNEYS United States Patent 3,518,849 HIDE PROCESSING METHOD AND APPARATUS William S. Eggleston, Menlo Park, Calif., assignor of ten percent each to Jon Legallet, Jok Legallet, Joe Legallet, and Paul Legallet III, Burlingame, Calif., and twenty percent each to Harvey T. Solveson, Menlo Park, and
Harold Morgan, San Rafael, Calif.
Filed Nov. 26, 1968, Ser. No. 779,036 Int. Cl. C14c 15/00 US. Cl. 69-30 23 Claims ABSTRACT OF THE DISCLOSURE Animal hides are processed in an elongated, internally finned drum rotated about an axis which is inclined from both the vertical and the horizontal to produce a spiral blending and kneading action on the hides.
BACKGROUND OF THE INVENTION Field of the invention This invention relates to methods and apparatus for processing animal hides to be converted to leather.
Description of the prior art There are several steps that may be involved in processing hides to leather. These steps may include the following:
(1) Brining.-Washing in water and salting to preserve the hides for a period of about up to one year prior to subsequent processing. In the prior are a brine race- Way is used for brining. This brine raceway is a concrete oval pit with a concrete center island and paddle arrangement to keep the hides moving in the raceway.
(2) Dehairing.Tumbling the hides in a Wooden drum (as discussed below) with intermittent soaking over a 12 hour period to remove the hair from the hide.
(3) Liming.A second step of dehairing.
(4) Bare and pickling.Using an enzyme to take out undesirable proteins. Bate is cleaning. Pickling is putting in an acid condition for tanning.
(S) Twnning.Adding chromic oxide to convert the hide to leather.
(6) Coloring and fat liqu0ring.Coloring is adding a dye. Fat liquoring is adding oils to make the leather soft.
In the prior art processing of hides, a wooden drum has been used. The wooden drum is, in effect, a churn. It is normally about feet in diameter by about 8 feet in width. The inside surface of the drum has shelves and pegs which produce a tumbling action on the hides loaded in the drum. The hides are loaded into the drum through a door in the peripherial surface of the drum. The useable capacity of the drum is less than one-half of the total capacity. That is, the processing operation requires that different chemicals be added at different times. Chemicals are fed through the gudgeon of the drum. As the gudgeon also is the trunnion of the drum as it turns, this is a limiting factor. You can not have the level of the processing solution above the level of the gudgeon. Also, the tumbling action required imposes a limitation on the amount of material that can be loaded in the drum and still produce adequate tumbling action.
SUMMARY OF THE INVENTION The present invention has both method and apparatus aspects.
The present invention includes an elongated drum mounted for rotation about an axis that is inclined from both the horizontal and vertical. The drum is large enough to hold a large quantity of cattle hides or other animal hides.
3,518,849 Patented July 7, 1970 "ice The inside surface of the drum has spiral fins which produce a spiral blending action when the drum is rotated. The fins also aid in charging and discharging hides in the drum (as will be described in greater detail below). The fins have beads on the inner edges of the fins. The beads serve two functions. The beads serve to prevent tearing of the hides. The beads also permit the hides to go completely against the inner face of the drum in the vicinity of the fins.
Because the axis of rotation of the drum is tilted at a substantial angle from the horizontal, the upper end of the drum may be left open. No closurer is required.
The coaction between the tilt of the drum, the spiral blading of the fins and rotation of the drum in a loading and blending direction keeps the hides and processing solution in the drum. The drum can be loaded to about -85% of its volumetric capacity.
Reversing the direction of the rotation of the drum will cause the fins to auger the hides out of the drum.
There is definite and important labor saving (as contrasted to the prior art) in both charging and discharging. In charging, since the opening is slanted rather than being straight up and down, the drum lends itself to hopper feeding and/or automatic loading by some other apparatus, such as a conveyor belt.
In the prior art, loading and discharging are basically manual operations. In their prior art loading and discharging are cumbersome.
The present invention produces a better action than the prior art mill type of wooden drum. The hides come out cleaner. There is some degree of scudding. More of the hair roots and dirt are removed (with the present invention) than with the prior art wooden drum techniques.
The mechanical action produces a better end product. The present invention produces a kneading and blending action. As noted above, the present invention produces a certain degree of scudding. Scudding is a spiral surface treatment in the prior art.
An important feature of the present invention is the fact that the drum is mobile. The drum, and the drive rotating the drum, can be taken right to the slaughterhouse. That is, the drum can be mounted on a wheeled trailer and can be towed by a semitractor to and from the slaughterhouse and tannery.
This makes it possible to pick up fresh stock at the slaughterhouse and begin processing before the hides have a chance to deteriorate.
Deterioration is a problem.
Deterioration shows up in several ways. It shows up as pin-holes, as salt stains and as actual rotting of the hide.
Deterioration starts within two hours.
With the present invention the hides can be loaded directly in the drum at the slaughterhouse as the animals are killed and the hides are trimmed. The drum, in this case, contains water and a bacteriacide. The drum can be rotated to tumble and mix the hides on occasion during the time that the hides are being loaded in the drum.
At the end of the day the transporter with the drum is hooked up to a semitractor and towed back to the tannery. The drum can be rotated in route to start the dehairing process. The drum can be driven interchangeably from a power takeolf on the tractor and from the power drive at the plant. Alternatively, the drive rotating the drum can be mounted directly on the drum transporter trailer.
This produces a time saving; and, most important, the hides are started in process before they are damaged.
As noted above, the dehairing process takes about twelve hours. Only parts of the twelve hours are used 3 for mechanical action. At other time intervals of that twelve hour period the drum is standing stationary.
It is an important feature of the present invention that the drum will cure (brine cure) as Well as dehair. It is possible to go right to the slaughterhouse and brine cure. The entire curing operation can be done in the drum by washing and salting in the drum. It is not necessary to hide wash and then use a brine raceway to preserve the hides prior to further processing at a later time, as is necessary in the prior art.
A very considerable cost saving is possible because of the fact that it is not necessary to make the capital investment for the raceway and other processing apparatus of the prior art. One of the most important aspects of this invention relates to sewage affiuent disposal. In the prior art wooden drum technique unhairing hide to water weight ratio is a minimum of 1 to 1. In the prior art paddle technique unhairing hide to water ratio at times reaches 1 to 2. With the present invention a ratio of 3 to 1 is normal. This cuts down on sulfide and lime contaminated water approximately 70%, or increases hide weight processed 300%. Because of the increased pressure being put on tanneries to clean up their afiluent before dumping in municipal sewers, this is quite a help.
The drum can be used for some or for all of the processing involved in converting the hide to leather. If the shell of the drum is made of a plain steel and the drum is used for all of the processing, the inside of the drum has to be lined with some material that does not react with the chemicals used in the later parts of the leather processing procedure. In this case the drum can be lined with a suitable material, such as plastic and Fiberglas or stainless steel.
Accordingly, a drum constructed and operated in the manner described constitutes specific objects of this invention.
Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show preferred embodiments of the present invention and the principles thereof and what are now considered to be the best modes contemplated for applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.
.In the drawings:
FIGS. 1 and 2 are side elevation and end elevation views (in cross section) of a wooden hide processing drum constructed in accordance with the prior art;
FIG. 3 is a side elevation view of a hide processing drum constructed in accordance with the present invention;
FIGS. 4 and 5 are diagrammatic views illustrating the spiral blending action of the drum of the present invention on the hides being processed inside the drum;
FIG. 6 is a side elevation view, partly broken away to show details of the internal fins and drain arrangement;
FIG. 7 is an end elevation view of the drum shown in FIG. 3 showing the hides being augered out of the drum by the fins when the direction of rotation of the drum is reversed to unload the drum; and
FIG. 8 is a cross section view taken along the line and in the direction indicated by the arrows 88 in FIG. 6 and showing details of the drain arrangement.
FIGS. 1 and 2 show a wooden drum for processing hides constructed in accordance with the prior art. The prior art drum is indicated generally by the reference numeral 21. Hides are loaded into and unloaded out of the drum 21 through an opening in the periphery of the drum. This opening is closed by a door 22. The drum 21 is mounted for rotation on supports 23.
Chemicals and processing liquids are added through the conduit 24 which is coincident with the axis of rotation of the drum.
The drive for rotating the drum 21 is not shown, but V belts are commonly used for this purpose.
The mechanical action required to process the hides is produced by a series of shelves 26. As the drum is rotated, the shelves 26 pick up the hides and then drop the hides in a churn or mill type of action.
This prior art drum has a number of limitations. As noted above, not more than half of the capacity of the drum can be used. Loading and unloading through the opening covered by the door 22 is a difiicult and cumbersome operation. The hides quite commonly clog up the opening during unloading. Drainage is dilficult. When the door 22 is replaced with a screen to drain the drum, the hides often cover the opening and prevent effective drainage.
In FIG. 3 a drum construction in accordance with one embodiment of the present invention is indicated generally by the reference numeral 31.
The drum 31 is an elongated drum which is mounted for rotation about an axis inclined from both the horizontal and the vertical. With particular reference to FIG. 6, the drum is mounted for rotation in a rear support 32 and on a front support 33. The upper end of the drum is rotatable on rollers 34.
The upper end of the drum has an opening 36 and the portion of the drum below the level of this opening forms the hide treatment zone as shown generally by the fluid in FIG. 6.
A drive motor 37 is connected to drive the drum in either direction of rotation and at different speeds of rotation. The drive motor may be a hydraulic drive motor.
The inside of the drum has a plurality of working elements in the form of spiral shaped fins 38. The fins extend normal to the inner face of the drum, are circumferentially spaced from one another and are disposed in spirals as illustrated whereby the fins move through the hide treatment zone with components of axial and transverse motion to produce a highly eificient blending and kneading action on the hides when the drum is rotated in one direction. The fins auger the hides out of the drum through the opening 36 when the drum is rotated in the opposite direction.
The inner edge of each fin 38 is formed with a round bead 39 (see FIG. 8) which helps to prevent tearing of the hides and which also permits the hides to move into contact with the inner face of the drum closely adjacent the base of the fin 38-.
The drum 31 includes a plurality of circumferentially spaced drain openings 41, and these circumferentially spaced drain openings 41 may also be placed at one or more locations along the length of the drum.
Plugs 42 are used to close off the drain openings 41.
Each drain opening is covered on the inside by a guard or screen 43 which acts as a sieve to prevent clogging. The screen 43 extends circumferentially about the inside of the drum and is arch shaped (as best shown in cross section in the lower part of FIG. 6). This screen arrangement prevents clogging of the drain openings and permits the drain opening to drain at any point on the underside of the drum. That is, so long as the drain opening is below the level of the processing solution, as indicated in FIG. 6, the screen 43 will permit liquid to run through the screen and out the drain opening without clogging.
As best shown in FIGS. 3 and 7 a conveyer 46 can be located beneath the opening 36 so that the hides H, when angered out of the drum by reversing the direction of rotation in the manner indicated in FIG. 7, can be readily transported away from the drum without any need to handle the hides manually.
As also illustrated in FIG. 3, a conveyer 47, hopper, or other automatic loading means can be associated with the open upper end of the drum 31 for automatic charging of the drum.
The mechanical action produced by the present invention is much better than that produced by the prior art. As illustrated in FIGS. 4-' and 5, the hides H are .given a spiral blending action which can be visualized as a continuous falling down hill. The lowermost hides in the drum are urged downwardly along the incline of the drum due to the spiral form of the fins and the weight of the remaining hides is imposed on these lowermost hides to resist free movement thereof and cause a kneading action as a portion of the lowermost hides overruns the fins. Inturn the uppermost hides circulate in the reverse axial direction until engaged by a fin. The hides H are not picked .up and dropped, as is the case with the shelves 26 of the ripr art drum. As pointed out above, this different mechanical action of the present invention is highly beneficial. r
The angle of inclination of the drum 31 can be varied and still produce this spiral blending action. As the angle of inclination of the rotational axis of the drum is increased, with respect to the horizontal, the capacity-of the drum is increased. It is possible to use 80-85% of the volumetric capacity of the drum for processing hides. The angle of inclination from the horizontal is limited only by the mechanical action required on the hides. If the angle is too great, the drum will not produce adequate mechanical action. While the angle from the horizontal disclosed in FIG. 3 is 18, which is considered optimal for a drum of the general configuration shown, it should be understood that a broad range of deviation from this precise inclination is permissible so long as the recited kneading action is preserved at high limits of inclination and the capacity for retention of a substantial weight of hides is preserved at the lower limit of inclination.
The drive motor 37 is preferably adapted to drive the drum at different speeds of rotation at different stages of processing of the hides. It is desirable to be able to rotate the drum 31 faster in the tanning operation than in some of the prior processing steps. A hydraulic drive motor, which permits continuous variation in the speed and close control of the speed can be used.
As noted above, the drum 31 can be mounted on a mobile transport vehicle, such as a trailer having wheels 40, so that the drum can be taken directly to the slaughterhouse.
While I have illustrated and described the preferred embodiments of my invention, it is to be understood that these are capable of variation and modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.
What is claimed is:
1. Apparatus for processing animal hides to be converted to finished leather, said apparatus comprising:
(A) means defining an elongated hide treatment zone, said means comprising an elongated, substantially imperforate cylindrical walled drum mounted for rotation about an axis inclined from the horizontal at a predetermined angle, said drum being closed at the lower end and having an opening at the upper end,
(B) means extending throughout substantially the entire length of said drum for working a substantial weight of hides within said zone, said means comprising at least one spiral fin aifixed to said cylindrical wall and extending inwardly therefrom, and
(C) drive means for rotating said drum in a direction to move said working means through the lower extent of said zone with a relative motion having downward axial and transverse components whereby:
the lowermost of said hides are conveyed downwardly under substantial pressure exerted by the weight of overlying hides, said pressure resisting free movement of said lowermost hides thereby forcing a portion thereof to overrun said working means and thus be kneaded thereby, said predetermined angle of inclination being within a range the upper limit of which preserves said kneading action and the lower limit of which preserves a capacity for said substantial weight of hides within said zone.
2. Apparatus as defined in claim 1 wherein the inner edge of each fin has a rounded bead to prevent damaging the hides and to permit the hides to go up against the inner surface of the drum adjacent the fins.
3. Apparatus as defined in claim 1 wherein said opening is adapted to remain open during rotation of said drum to facilitate loading and unloading the hides and loading processing solutions.
4. Apparatus as defined in claim 3 wherein the drive means include means for reversing the direction of rotation to cause the fins to auger the hides out of the opening.
5. Apparatus as defined in claim 4 including a conveyer beneath the opening for transporting the hides away from the drum as the hides are augered out of the opening.
6. Apparatus as defined in claim 3 including a hopper above the opening for loading hides into the drum while the drum is being rotated.
7. Apparatus as defined in claim 3 wherein the angle of inclination from the horizontal is sufficiently large to permit the drum to be loaded to about 80% of its volumetric capacity with hides and processing solution.
8. Apparatus as defined in claim 1 including drain openings in the drum and internal arched screens which extend circumferentially about the inside of the drum and over the drain openings to prevent blockage of the openings by the hides and to permit the drain openings to drain at any angle on the underside of the drum.
9. Apparatus as defined in claim 1 wherein the drive means include a hydraulic drive motor.
10. Apparatus as defined in claim 1 wherein the drum is a plain steel shell lined with a material that is chemically inert to all the chemicals needed to process the hides to leather.
11 Apparatus as defined in claim 10 wherein the lining is made of plastic and Fiberglas.
12:. Apparatus as defined in claim 10 wherein the lining is a stainless steel lining.
13. Apparatus as defined in claim 1 including a wheeled carriage for the drum which permits the drum to be transported back and forth between a slaughterhouse and a tannery and wherein the drive means are connected to rotate the drum to process the hides in route.
14. A method of processing animal hides to be converted to finished leather, said method comprising the steps of:
(A) establishing an elongated treatment zone in a rotary drum having a major axis inclined from the horizontal at a predetermined angle,
(B) confining a fluid within said zone,
(C) loading a substantial weight of hides into said zone,
(D) rotating said drum to pass a working element in substantially the form of an elongated fin downwardly through the lower extent of said zone with a motion having axial and transverse components, thereby:
(a) conveying the lowermost of the hides downwardly in the axial direction of said inclined elongated treatment zone while (b) maintaining pressure thereupon by the weight of the remaining hides, said pressure (A) resisting free movement of said lowermost hides, thereby (B) forcing a portion thereof to overrun said working elements and thus be kneaded thereby, and
7 (E) permitting free movement of the uppermost of said hides in a reverse axial direction, said predetermined angle falling within a range the upper limit of which preserves said kneading action and the lower limit of which preserves a capacity for said substantial load in said drum.
15. The method of processing animal hides as set forth in claim 14 wherein processing fluids are withdrawn through a path originating in the lower confines of said zone.
16. The method of processing animal hides as set forth in claim 14 wherein said substantial weight of hides bears a relationship to the weight of said processing fluid of approximately 3 to 1.
17. The method of processing animal hides as set forth in claim 14 wherein the combined volume of hides and fluid equals approximately 80% of the volume of said confined zone.
18. The method of processing animal hides as set forth in claim 14 wherein said step of loading the hides into the treatment zone is accomplished by passing the hides through a path including an opening at an upper extension of said axis above said treatment zone.
19. The method of processing animal hides as set forth in claim 18 wherein said step of loading the hides into the treatment zone takes place while said working movement is in progress.
20. The method of processing animal hides as set forth in claim 18 wherein said opening is maintained throughout the processing operation to permit visual observation thereof.
21. The method of processing animal hides as set forth in claim 18 wherein said treatment fluid is passed to said treatment zone through said opening.
22. The method of processing animal hides as set forth in claim 18 including the additional step of reversing the direction of movement of said working element at termination of said treatment to convey said hides upwardly through said opening to remove them from said processing' zone.
23; The method of processing animal hides as set forth in claim 22 including the additional step of transporting said treatment zone during the interval between said step of loading and said step of removal.
References Cited UNITED STATES PATENTS 567,574 9/1896 Barrett 68l46 X 2,029,126 1/1936 Rybeck 259 X 2,676,003 4/1954 Oury 259--177 2,685,188 8/1954 Landon 68139 X 3,080,152 3/1963 Lendved 259l77 X 3,161,403 12/1964 Lincoln et al. 259l77 X 3,164,002 1/1965 Rossi 6930 3,349,582 10/1967 Quinn et al. 69-30 FOREIGN PATENTS 225,460 12/ 1924 Great Britain.
ALFRED R. GUEST, Primary Examiner