US3141485A - Tobacco shredder - Google Patents

Tobacco shredder Download PDF

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US3141485A
US3141485A US24258462A US3141485A US 3141485 A US3141485 A US 3141485A US 24258462 A US24258462 A US 24258462A US 3141485 A US3141485 A US 3141485A
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Prior art keywords
rotor
shaft
balancing
members
teeth
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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Jr Charles W Bonner
Curtis T Houck
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Cardwell Machine Company
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Cardwell Machine Company
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    • AHUMAN NECESSITIES
    • A24TOBACCO; CIGARS; CIGARETTES; SMOKERS' REQUISITES
    • A24BMANUFACTURE OR PREPARATION OF TOBACCO FOR SMOKING OR CHEWING; TOBACCO; SNUFF
    • A24B5/00Stripping tobacco; Treatment of stems or ribs
    • A24B5/10Stripping tobacco; Treatment of stems or ribs by crushing the leaves with subsequent separating

Description

July 21, 1964 c. w. BONNER, JR.. ETAL 3,141,485

TOBACCO SHREDDER Filed Dec. 4, 1962 2 Sheets-Sheet 1 1lllll um BY g ATTORNEYS July 2l, 1964 c. w. BONNER, JR., ETAL 3,141,485

TOBACCO SHREDDER Filed Deo. 4, 1962 2 Sheets-Sheet 2 BY (5f i M g ATTORNEYS United States Patent O 3,141,485 TOBACCO SDDER Charles W. Bonner, Jr., and Curtis T. Houck, Richmond, Va., assignors to The Cardweli Machine Company, Richmond, Va., a corporation of Virginia Filed Dec. 4, 1962, Ser. No. 242,584 2 Claims. (Cl. 14o-117) The present invention relates in general to threshing machines of the general type having a rotary threshing element with radially extending arms constituting teeth or knives adapted to travel with respect to stationary blades or teeth, especially adapted for ripping and tearing of leaf lamina from stems and large veins of tobacco leaves.

More particularly, the present invention relates to the structure of the rotary threshing element having radial teeth to facilitate regulation of the static and dynamic balance of the rotary element. Heretofore, it has been ditiicult to achieve and maintain proper static and dynamic balance of the rotary threshing element of tobacco threshers and the like.

The number and location of the radial teeth or knives is subject to wide variation, frequently uneven numbers of knives are mounted on the rotor which must be compensated for to provide proper balance, differences in the effective mass and shape of mass produced knives occur which introduce different balancing requirements, and Wear of the cutting edges of the knives occurs during use which produces a change in balance conditions.

An object of the present invention, therefore, is the provision of a novel threshing machine for tobacco leaves and similar products, wherein static and dynamic balance of the moving parts may be readily achieved and maintained.

Another object of the present invention is the provision of a tobacco threshing machine having a novel rotor element provided with radially extending teeth, wherein means are provided for readily adjusting the static and dynamic balance of the rotor.

Another object of the present invention is the provision of a novel tobacco threshing machine of the type having a rotor element including a cylinder assembly formed of a plurality of spaced parallel circular plates keyed to a shaft and fixed in a group by lock rods, and radial teeth members interposed between selected pairs of said plates wherein adjustable eccentric balancing members are provided in said cylinder assembly to establish static and dynamic balance thereof.

Other objects, advantages and capabilities of the present invention will become apparent from the following detail description, taken in conjunction with the accompanying drawings illustrating a preferred embodiment of the invention.

In the drawings:

FIGURE l is a vertical section view of a threshing machine embodying the present invention, which section is taken transversely of the axis of rotation;

FIGURE 2 is a side elevation, partly broken away, of the rotor assembly shown in FIGURE 1;

FIGURE 3 is a vertical transverse section view taken along the line 3--3 of FIGURE 2;

3,141,485 Patented July 21V, 1964 FIGURE 4 is an enlarged detailed side elevation of one of the eccentric balancing discs; and

FIGURE 5 is a fragmentary section view taken along the line 5 5 of FIGURE 1.

Referring to drawings, wherein like reference characters designate corresponding parts throughout the several gures the tobacco threshing machine of the present invention, indicated in general by the reference character lil, includes a housing or casing 11 having a pair of side walls 12, and an upstanding end wall assembly 14 at one end thereof, having an access door 14a, and an upstanding end wall assembly 15 forming the opposite wall, which includes a pivoted concave access door 16. A leaf charging or inlet opening 17 is formed at the upper end of the housing l1 and the lower end of the housing is open to provide a large discharge opening 18.

A threshing rotor 19 is disposed within the housing 11 directly below the charging opening 17, and includes a main shaft 20 journaled in bearing brackets iixed to the side walls 12. Supported on the main shaft 20 is a cylinder assembly 21 formed by a series of circular plates 22 disposed in parallel planes in axial alignment with each other along the shaft 2t). The circular plates 22 are spaced from each other for the reception therebetween of rotor teeth or knives 23 which are secured against rotation with respect to their associated plates 22 by parallel flanges 24, The flanges 24 are Welded or otherwise fixed to the plates 22 and form sockets into which the inner end portions of the teeth 23 are snugly fitted. The teeth 23 are locked in place by means of rods 25 which extend parallel to the axis of the main shaft 2) and through selected ones of the holes 26 disposed in equally circumferentially spaced relation along a circular path near the perimeter of each plate 22 concentric with the axis of the main shaft 20. The rods 25 also extend through accommodating openings in the teeth 23.

End plates 27, 23 are provided at the opposite ends of the cylinder assembly 21 to retain the circular plates 22 and knives 23 in assembled relation, and include a central hub portion 29 having a circular opening therein sized to accommodate the main shaft 20 and interrupted by keyway 29' into which is disposed a key 30 which also extends into an elongated keyway 20 in the main shaft 2?. A set screw 31 is also provided in the hub 29 to tightly press key 3i) into the keyway 20 and restrain end plates 27, 28 and the cylinder assembly 21 against axial displacement along the main shaft 20. End plates 27, 28 have suitable apertures therein, indicated at 32, and arranged in a pattern similar to that of the holes 26 in the circular plates 22 to receive the end portion of the rods 25. Any suitable locking means such as disc washers 33 and cotter pins 34 or other known fasteners may be provided at the ends of the rods 25 to restrain the means in the desired assembly relation with the end plates 27, 28.

It will be appreciated that many different tooth arrangements rnay be provided in cylinder assembly 21, and that different static and dynamic balancing conditions will be obtained depending upon the particular tooth arrangement which is chosen. Further, teeth 23 may be aassembled in uneven numbers on the cylinder assembly alanine 21 which obviously provides an unbalanced condition which has to be compensated for. Also variation in the weight, configuration and force moment effects of the teeth may be encountered due to variations occurring as a result of mass production. All of these features may be accommodated by providing some means for readily altering the static and dynamic balancing condition of the rotor assembly, both at the factory and in the field so that the rotor assembly can be properly balanced notwithsanding the many variations which might occur.

Balance of the rotor is accomplished in the present invention by means of eccentric disc balancing members 35 having eccentrically disposed openings 36 therein to accommodate a supporting rod 37. The eccentric opening 36 has a keyway 36 along a peripheral portion thereof for receiving key 38 which projects into an elongated keyway 37', in the rod 37 and supports the eccentric disc 35 for rotation with the rod 37. A number of eccentric disc members 35 are provided on each rod 37 at axially spaced positions therealong, for example four ccentric discs members 35 spaced at opposite ends and at approximately l ft. intervals along rod .37 as illustrated in the accompanying drawings. Three sets of rods 37 and accompanying disc members 35 are provided in the embodiment herein illustrated, spaced radially and circumferentially relative to the axis of the main shaft 2d. The ends of the rod 37 are threaded to receive socket heads 39, 40, the socket head 39 at one end of the rod 37 being welded thereto to permit rotation of the rod 37 by a suitable tool, and being provided with a set screw d1 to bear against the adjacent end plate 2S to restrain rod 37 in a particular angular adjustment position. An indicating mark, such as the arrow 39', may be provided on the head 3&1 to denote the angular position of the associated rod 37 and the eccentric disc members 35 keyed thereon.

The teeth 23 of the rotor 19 work against a concave grid 42 which extends in substantially concentric relation below the rotor 19 so that the curvature of the grid 42 follows the axis of rotation of the rotor. The grid 42 may be formed of a concavcly curved sheet metal plate which is provided with rows of zigzag shaped or other conventionally congurated slots or openings 43, and is spaced slightly from the outer ends of the teeth of the rotor to retain the material which is being threshed and prevent it from falling too quickly away from the region of the tooth action.

To co-act with the teeth 23 in removal of loaf lamina from stems and heavy veins, a plurality of stationary knives 44 are located to the right and left of the rotor 19 slightly above the axis of the rotor, as viewed in FIGURE 1, the stationary knives 44 being disposed in side-by-side transverse alignment with their bases inserted in the slots of multislotted knife bars d5 which may conveniently be carried by parts of the access doors 14a and 16. Each slotted knife bar d5 may include two opposite end blocks 46 located at opposite ends of slotted walls 47 extending in parallel horizontal relation, the walls 47 being provided on their adjacent faces with alternate ridges and grooves 4S and 49 providing slots into which the knives 4-4 may be inserted. The bases of the knives d4 and the end blocks 4o are apertured to receive therethrough locking rods 5@ similar in construction and operation to the locking rods 25, of the rotor 1i". Additional end plate members 51 are provided at the opposite ends of the slotted knife bars 45 and include a depending tab or tail 52 shaped to prevent the curved grid 42 from becoming loose and shifting out of its normal position into obstructing relation to the rotor teeth 23.

In the operation of the invention to thresh tobacco leaves, the tobacco leaves introduced through the charging opening 17 are picked up by the teeth 23 of the rotor 19 and advanced in a clock-wise direction, as viewed in FIGURE 1, along an arcuate path adjacent the concave grid 42. The teeth 23 advancing through the mass of tobacco leaves rips leaf lamina from the tobacco leaves in the zone of the stationary knives 44. at the right and left of the rotor axis and over the extent of the grid 42. When the tobacco is ripped to an appropriate small size, it then passes through the openings 43 in the grid member 42 and is discharged through the opening 18.

T he static and dynamic balance of the threshing rotor 19 can be readily adjusted at the factory by tightening the right hand socket head 40 to about thirty-tive pounds of torque, and if desired pinning the socket head 4t) against further rotation relative to the associated rod 37 by a suitable taper pin or the like, and then rotating the socket head 3% with a suitable tool to position the eccentric balancing members 35 on the associated rod 37 so as to place the rotor 19 in balance. When the position of all of the sets of balancing members 35 is properly established, the set screws 41 are tightened down to lock their associated socket heads 39 against movement relative to the adjacent end plate 28. Thereafter, if the rotor 19 gets out of balance due to any cause, the static and dynamic balance thereof can be readily re-established by loosening the set screws 41 and re-adjusting the position of the balancing members 35 by rotation of the socket heads 39. Due to the arrangement and location of the sets of balancing members 35, substantial out of balance conditions can be compensated for, even to the point of compensating for uneven numbers of teeth 23 where the design considerations require such an arrangement.

While but one preferred example of the present invention has been particularly shown and described, it is apparent that various modifications may be made therein Within the spirit and scope of the invention, and it is desired, therefore, that only such limitations be placed on the invention as are imposed by the prior art and set forth in the appended claims.

What is claimed is:

1. In a rotor assembly for threshing machines and the like including a shaft, a group of circular discs of substantially planar configuration disposed in axial alignment in axially spaced parallel planes on said shaft, means for retaining said discs in fixed relation to each other and to said shaft for rotation as a group with said shaft, elongated radially projecting tooth members extending beyond the peripheries of said discs having inner end p01'- tions disposed in the spaces between adjacent pairs of said discs, and means for fixing said tooth members in radially extending relation to said discs adjacent the .peripheries of the latter at a plurality of circumferentially spaced locations along said peripheries, the improvement comprising a plurality of balancing disc members each having an eccentric hole therein, parallel balancing rods extending in axially offset relation to said shaft through said discs at a plurality of circumferentially spaced locations relative to said shaft, means supporting a plurality of said disc members on each of said balancing rods between selected pairs of said discs for rotary movement with their associated balancing rod, means external of an endmost one of said discs for rotating each of said balancing rods to dispose said disc members at selected angular positions to place the rotor assembly in static and dynamic balance, and means for releasibly locking said rods at their selected angular positions.

Z. In a threshing machine having a rotary threshing element with radially extending teeth adapted to pass over and closely adjacent to a concave grid, the rotary threshing element comprising a horizontal shaft, a group of circular plates xed to the shaft in axial alignment with each other and spaced axially of the shaft to lie in parallel planes and receive end portions of the teeth therebetween, end plate members fixed on said shaft at opposite ends of said group of circular plates, means for fixing teeth in radially extending relation to said circular plates adjacent the peripheries of the latter at any of a plurality of circumferentially spaced positions along said peripheries, a plurality of balancing disc members each having an ec- 5 centric hole therein, a plurality of balancing rods arranged in parallelism with said shaft and radially offset from said shaft at a plurality of circumferentially spaced locations, means supporting a plurality of said disc members on each of said balancing rods between selected pairs of said discs for rotary movement with their associated balancing rod, means accessible from externally of the rotary threshing element for rotating each of said balancing rods to dispose the rotor assembly in static and dynamic balance, and

6 means for releasably locking said rods at their selected angular positions.

References Cited in the tile of this patent UNITED STATES PATENTS 1,314,575 Davidson Sept. 2, 1919 2,760,492 Allen Aug. 28, 1956 2,963,921 Brough et al Dec. 31, 1960 FOREIGN PATENTS 310,363 Great Britain Jan. 16, 1930

Claims (1)

1. IN A ROTOR ASSEMBLY FOR THRESHING MACHINES AND THE LIKE INCLUDING A SHAFT, A GROUP OF CIRCULAR DISCS OF SUBSTANTIALLY PLANAR CONFIGURATION DISPOSED IN AXIAL ALIGNMENT IN AXIALLY SPACED PARALLEL PLANES ON SAID SHAFT, MEANS FOR RETAINING SAID DISCS IN FIXED RELATION TO EACH OTHER AND TO SAID SHAFT FOR ROTATION AS A GROUP WITH SAID SHAFT, ELONGATED RADIALLY PROJECTING TOOTH MEMBERS EXTENDING BEYOND THE PERIPHERIES OF SAID DISCS HAVING INNER END PORTIONS DISPOSED IN THE SPACES BETWEEN ADJACENT PAIRS OF SAID DISCS, AND MEANS FOR FIXING SAID TOOTH MEMBERS IN RADIALLY EXTENDING RELATION TO SAID DISCS ADJACENT THE PERIPHERIES OF THE LATTER AT A PLURALITY OF CIRCUMFERENTIALLY SPACED LOCATIONS ALONG SAID PERIPHERIES, THE IMPROVEMENT COMPRISING A PLURALITY OF BALANCING DISC MEMBERS EACH HAVING AN ECCENTRIC HOLE THEREIN, PARALLEL BALANCING RODS EXTENDING IN AXIALLY OFFSET RELATION TO SAID SHAFT THROUGH SAID DISCS AT A PLURALITY OF CIRCUMFERENTIALLY SPACED LOCATIONS RELATIVE TO SAID SHAFT, MEANS SUPPORTING A PLURALITY OF SAID DISC MEMBERS ON EACH OF SAID BALANCING RODS BETWEEN SELECTED PAIRS OF SAID DISCS FOR ROTARY MOVEMENT WITH THEIR ASSOCIATED BALANCING ROD, MEANS EXTERNAL OF AN ENDMOST ONE OF SAID DISCS FOR ROTATING EACH OF SAID BALANCING RODS TO DISPOSE SAID DISC MEMBERS AT SELECTED ANGULAR POSITIONS TO PLACE THE ROTOR ASSEMBLY IN STATIC AND DYNAMIC BALANCE, AND MEANS FOR RELEASIBLY LOCKING SAID RODS AT THEIR SELECTED ANGULAR POSITIONS.
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Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3490705A (en) * 1967-04-07 1970-01-20 Fibrelite Corp Hammermill for grinding fibrous materials
US3611829A (en) * 1970-02-09 1971-10-12 Giddings & Lewis Balancing arrangement for armature assemblies
US3817464A (en) * 1972-11-27 1974-06-18 Koehring Co Single blade recutter for forage harvester
US3827643A (en) * 1972-02-05 1974-08-06 Maier Kg Maschf B Wood comminuting apparatus
US3874605A (en) * 1974-04-03 1975-04-01 Gehl Co Chopping cylinder for forage harvesters or the like
US3904138A (en) * 1973-04-13 1975-09-09 Maier Kg Maschf B Holding device for knife sets in a shredding device
US3904139A (en) * 1973-04-13 1975-09-09 Maier Kg Maschf B Drum-shaped knife cage with replaceable knife sets
US4077573A (en) * 1976-01-23 1978-03-07 Amf Incorporated Independently mounted thresher cutters
US4098466A (en) * 1975-03-03 1978-07-04 Macelvain Robert C Impact mill for reducing solids
US4195646A (en) * 1977-05-17 1980-04-01 Philip Morris Incorporated Process for shredding tobacco stems
US4285348A (en) * 1980-03-14 1981-08-25 Hartman L. Gearhiser Threshing machine
US4294415A (en) * 1978-08-22 1981-10-13 Kraemer & Grebe Gmbh & Co. Kg Maschinen- Und Modellfabrik Cutter knife
US4753395A (en) * 1987-01-28 1988-06-28 Ralston Purina Company Lump breaker for food processing
US4770353A (en) * 1986-09-26 1988-09-13 G. Walter Steffens Gmbh & Co. Arrangement for balancing blade assemblies
WO1990014020A1 (en) * 1989-05-26 1990-11-29 The Cardwell Machine Company (Uk) Limited Apparatus and method for processing inhomogeneous material such as tobacco
US5330109A (en) * 1991-12-19 1994-07-19 Ti Interlock Limited Control operation of a clutch drive system
EP0848914A1 (en) 1996-12-17 1998-06-24 Imperial Tobacco Limited Apparatus and process for threshing tobacco
WO2001093705A1 (en) 2000-06-02 2001-12-13 Imperial Tobacco Limited Apparatus and process for threshing tobacco
US8375826B1 (en) * 2011-12-15 2013-02-19 Cnh America Llc Self balancing chopping or threshing rotor

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1314575A (en) * 1919-09-02 Balancing device
GB310363A (en) * 1928-04-24 1930-01-16 Gessner Ernst Ag New or improved method of and means for balancing rotary bodies
US2760492A (en) * 1953-05-14 1956-08-28 Cardwell Machine Company Inc Stationary tooth mounting for a rotary type thresher
US2963921A (en) * 1957-07-05 1960-12-13 Brough William Means for mounting a member for rotation

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1314575A (en) * 1919-09-02 Balancing device
GB310363A (en) * 1928-04-24 1930-01-16 Gessner Ernst Ag New or improved method of and means for balancing rotary bodies
US2760492A (en) * 1953-05-14 1956-08-28 Cardwell Machine Company Inc Stationary tooth mounting for a rotary type thresher
US2963921A (en) * 1957-07-05 1960-12-13 Brough William Means for mounting a member for rotation

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3490705A (en) * 1967-04-07 1970-01-20 Fibrelite Corp Hammermill for grinding fibrous materials
US3611829A (en) * 1970-02-09 1971-10-12 Giddings & Lewis Balancing arrangement for armature assemblies
US3827643A (en) * 1972-02-05 1974-08-06 Maier Kg Maschf B Wood comminuting apparatus
US3817464A (en) * 1972-11-27 1974-06-18 Koehring Co Single blade recutter for forage harvester
US3946954A (en) * 1972-11-27 1976-03-30 Koehring Company Single blade recutter for forage harvester
US3904138A (en) * 1973-04-13 1975-09-09 Maier Kg Maschf B Holding device for knife sets in a shredding device
US3904139A (en) * 1973-04-13 1975-09-09 Maier Kg Maschf B Drum-shaped knife cage with replaceable knife sets
US3874605A (en) * 1974-04-03 1975-04-01 Gehl Co Chopping cylinder for forage harvesters or the like
US4098466A (en) * 1975-03-03 1978-07-04 Macelvain Robert C Impact mill for reducing solids
US4077573A (en) * 1976-01-23 1978-03-07 Amf Incorporated Independently mounted thresher cutters
US4195646A (en) * 1977-05-17 1980-04-01 Philip Morris Incorporated Process for shredding tobacco stems
US4294415A (en) * 1978-08-22 1981-10-13 Kraemer & Grebe Gmbh & Co. Kg Maschinen- Und Modellfabrik Cutter knife
US4285348A (en) * 1980-03-14 1981-08-25 Hartman L. Gearhiser Threshing machine
US4770353A (en) * 1986-09-26 1988-09-13 G. Walter Steffens Gmbh & Co. Arrangement for balancing blade assemblies
US4753395A (en) * 1987-01-28 1988-06-28 Ralston Purina Company Lump breaker for food processing
WO1990014020A1 (en) * 1989-05-26 1990-11-29 The Cardwell Machine Company (Uk) Limited Apparatus and method for processing inhomogeneous material such as tobacco
US5330109A (en) * 1991-12-19 1994-07-19 Ti Interlock Limited Control operation of a clutch drive system
EP0848914A1 (en) 1996-12-17 1998-06-24 Imperial Tobacco Limited Apparatus and process for threshing tobacco
WO1998026677A1 (en) 1996-12-17 1998-06-25 Imperial Tobacco Limited Apparatus and process for threshing tobacco
WO2001093705A1 (en) 2000-06-02 2001-12-13 Imperial Tobacco Limited Apparatus and process for threshing tobacco
US8375826B1 (en) * 2011-12-15 2013-02-19 Cnh America Llc Self balancing chopping or threshing rotor

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