US566234A - Rotary harrow - Google Patents

Rotary harrow Download PDF

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US566234A
US566234A US566234DA US566234A US 566234 A US566234 A US 566234A US 566234D A US566234D A US 566234DA US 566234 A US566234 A US 566234A
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shaft
tools
arms
pinions
collars
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    • AHUMAN NECESSITIES
    • A01AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01BSOIL WORKING IN AGRICULTURE OR FORESTRY; PARTS, DETAILS, OR ACCESSORIES OF AGRICULTURAL MACHINES OR IMPLEMENTS, IN GENERAL
    • A01B33/00Tilling implements with rotary driven tools, e.g. in combination with fertiliser distributors or seeders, with grubbing chains, with sloping axles, with driven discs
    • A01B33/02Tilling implements with rotary driven tools, e.g. in combination with fertiliser distributors or seeders, with grubbing chains, with sloping axles, with driven discs with tools on horizontal shaft transverse to direction of travel
    • A01B33/021Tilling implements with rotary driven tools, e.g. in combination with fertiliser distributors or seeders, with grubbing chains, with sloping axles, with driven discs with tools on horizontal shaft transverse to direction of travel with rigid tools

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  • the invention relates to an improvement in that class of harrows wherein the pulverizing-tools are made to engage the ground with a rotary movement; and the principal object of the invention is to improve the construction of these pulverizing-tools and to provide in place of the ordinary disks a series of radial arms which have certain peculiar features of construction whereby their efficiency is increased, and which are positively driven at a greater speed than the groundwheels by gearing them with moving parts of the machine, this forced rotation of the tools being considered more effective than where the tools merely engage and rotate idly by reason of their contact with the earth.
  • a further object of the invention is to provide improved means by which the driving of the pulverizing-tools may be effected, and also to make it possible to throw said tools in and out of gear by a simple and easy movement.
  • Figure 1 represents a perspective View of my complete harrow.
  • Fig. 2 is a vertical longitudinal section thereof.
  • Fig. 3 is a sectional View taken parallel with the shaft upon which the pulverizing-tools are mounted and extending through the sup porting-arms of this shaft to the main axle of the machine.
  • Fig. 4 is a detail section taken through one of the pinions which are affixed to the tool-carrying shaft, and showing the clutch devices.
  • Fig. 5 is a detail view of the devices for throwing the pinion in and out of engagement with the driving-gear.
  • Fig. 6 is a detail perspective illustrating the preferred means for securing the pulverizing-tools to the shaft.
  • Fig. 1 represents a perspective View of my complete harrow.
  • Fig. 2 is a vertical longitudinal section thereof.
  • Fig. 3 is a sectional View taken parallel with the shaft upon which the pulverizing-tools are mounted and extending through the sup port
  • Fig. 7 is a sectional view illustrating a modification of these means.
  • Fig. 8 is a detail perspective of a modified arrangement of means for throwing the pinions of the tool-carrying shaft out of engagement with their respective driving-gears.
  • Fig. 9 is a detail plan View of a part of the frame.
  • the frame of my improved machine comprises a metallic cross-bar or casting 1, having at its extremities the rearwardly-projecting arms 2, provided with boxes 3, in which the axle 4 is mounted and is capable of rock ing movement. Projecting rearwardly from the middle of the casting 1 are similar arms 5, carrying boxes 6, through which the axle 4 also extends.
  • the 7 indicates a forwardly-proj ectin g arm pro vided with suitable flanges or ribs for receiving the tongue 8 of the machine.
  • One of the arms 5, and preferably the left-hand arm has an extension 9,which extends rearwardly and upwardly and is provided with flanges or ribs to engage the spring-standard 10.
  • the standard 10 is rigidly bolted to the extension 9 and has its upper end bent to lie in a horizontal plane to support the seat 11.
  • the arms 16 Arranged 011 the rock'shaft or axle 4: contiguous to the boxes 3, are the arms 16 which have their inner ends formed with bossed openings 17, rigidly affixed to the shaft by means of pins or keys 18, which pass through the bosses and through the shaft. These arms 16 extend rearwardly from the shaft or axle to points adjacent to the driving-gears 14, where they are provided with transverselyalined openings 19 and outer flanges or bosses 20, said flanges being provided at their outer ends with annular grooves 21.
  • the shaft 22 Removably mounted in the openings 19 of the arms 16 is the shaft 22, which extends parallel with the rock-shaft or axle and projects at its ends beyond the arms 16.
  • a longitudinal groove 23 Formed in that portion of each end of the shaft 22 which projects beyond the arm 16 is a longitudinal groove 23, in which is fitted a pawl-plate 24, having a beveled face 25.
  • pawl-plates 24 are actuated by bow-spring. 20, located within the grooves 24.
  • the pinions 27 are mounted upon the ends of the shaft 22 for free movement in one direction, and hence the pinions will be fixed to the shaft when the machine is moving forward, and will turn loosely when the machine is moving backward. This enables the machine to be backed without causing the pulverizin g-tools to be revolved.
  • each pinion 27 indicates two expansion-springs, which bear at their inner ends in the annular grooves 21 of the flanges 20 and at their outer ends within annular recesses 30, formed on the inner sides of the pinions 27, and by these means the said pinions are normally held in engagement with the cog-rims 14.
  • Formed at the inner end of each pinion 27 is an in ward extension 31, having an annular groove which receives the lower arm of the lever 32, whereby the pinions may be thrown in or out of engagement with the driving-gear.
  • the levers 32 are fulcrumed upon the brackets 33, which are in turn rigidly secured to or formed integral with the outer sides of the arms 16.
  • the inner shortarms of the levers 32 are provided with longitudinal slots 34, in which the pins 35 of the levers 36 are slidably mounted, so that when the levers 36 swing on their fulcrums the levers 32 will be correspondingly moved.
  • the levers 30 are fulcrumed upon the arms 16, and project upward approximately in alinement with the same.
  • 37 indicates a segment which is adapted for engagement by the pawl 38, each lever being provided with a pawl whereby they may be independently operated.
  • the pulverizing-tools 39 consist of a series of collars 40, which carry radial arms 41, preferably eight for each collar, and the extremities of the arms are arranged in a common opposite directions, so that in each set of arms 41 four fingers will be bent to one side and four to the other, and the edges of both arms and fingers are sharpened.
  • Formed integral with the inner collars and projecting out from each side thereof are the opposite extensions 43 and 44, two for each collar.
  • the collars of the terminal tools have only one extension, projecting inwardly, the opposite side being provided with a flange 45, through which fastening screws or pins may be passed into the shaft 22. By these means the end tools are rigidly secured to the shaft.
  • the projections or flanges 44 of all the tools 39 have their ends formed with concaved depressions or notches, which are respectively adapted to receive the correspondingly-convexed ends of the projections 43.
  • the pulveriZing-tools are rigidly mounted upon the shaft 22 without having to pierce said shaft for the reception of numerous fastening devices, which would tend to materially reduce the strength of the shaft.
  • the end tools he in g rigid and the intermediate tools being connected thereto, all are held properly in place.
  • Fig. 7 illustrates a modification of these devices in which the collars 40 are secured to sleeves or hollow shafts 46 and the latter are fixed to the shaft 22. This attains the end desired, but is not regarded as being as good as the extensions 43 and 44, principally for the reason that it makes the machine much heavier, and also that it increases the expense of building the machine.
  • a mutilated gear 47 Fixed to the axle 4, between the boxes (3 of the frame 1, is a mutilated gear 47, which meshes at this point with a mutilated gear 48, mounted upon a spindle 49, supported by the arms 50, which rise from the boxes 6.
  • the gear 48 is provided with a lever 51, which is operated contiguous to a ratchet-segment 52 on the right-hand arm 50, and this segment is engaged by a pawl 53, mounted in a casing or sleeve 54, aflixed to the lever. 55 indicates a rod which is pivotally connected to the pawl 53 and which extends to a hand-lever 50, fulcrumed to said upper end of the lever 51.
  • the axle 4 may be rocked in its bearings and the arms 16 correspondingly swung to raise or lower the toolshaft 22; also, by means of the ratchet 52 and pawl 53 the parts may be locked in the desired position.
  • the depth at which the pulverizing-tools operate may be regulated, causing them to merely scrape the surface of the ground or to operate any desired depth below the surface.
  • the shield 57 Rigidly secured to the axle 4 and curving rearwardly and downwardly from the same is the shield 57, which is arc-shaped in cross section and which embraces the pulverizing tools, so as to prevent dust from arising and clods and other articles from being thrown by the tools.
  • This shield has recesses or notches 58 formed in its ends adjacent to the arms 16 to receive the levers 36, so that the upper ends of said levers may project beyond the shield and be accessible to the operator.
  • This shield is preferably constructed of sheet metal.
  • the modification illustrated in Fig. 8 consists of a bar 59, rotatably mounted in a bracket at the outer side of the arm 16. 61 indicates a pin which passes through the bar 59 and rests upon the bracket 60, to support the bar.
  • the lower end of the bar 59 is provided with a horizontally and downwardly extending offset 62, which forms a crank, and the end of this portion is seated within the annular groove in the extension 31 of the adjacent gear 27.
  • the upper end of the bar 59 is formed with a lateral offset 63, which is disposed obliquely from the offset or crank 62, and which is provided to furnish means for oscillating the bar 59.
  • the crank 62 may be made to swing, thereby throwing the gear 27 in and out of engagement with its respective cog-rim.
  • the gear is not changed as to the grooves 28 and pawl-plates 24. It has, however, no spring, it being held in engagement with its respective rim It by the bar 59 and its several offsets, which operate to form a dead-center and to prevent the movement of the gear by power applied to it other than through the medium of the bar 59.
  • each tool comprising a collar, a series of radial arms flattened in a plane transverse to the axis of the shaft or parallel with the forward movement of the machine, and transversely bent or deflected terminal fingers at the extremities of the arms, said fingers extending in opposite directions upon alternate arms and the edges of the arms and fingers being reduced to form cutting edges, substantially as specified.

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Soil Sciences (AREA)
  • Environmental Sciences (AREA)
  • Soil Working Implements (AREA)

Description

(No Model.) 2 Sheets-Sheet 1.
A. SEWERSON. ROTARY HARROW No. 566,234. Patented Aug. 18, 1896.
(No Model.) 2 Sheets--Sheet 2.
A. SEWERSON.
ROTARY HARROW.
No. 566,234. Patented Aug. 18, 1896.
flndrew Sewersan W l l 92 sses I 12) @is Horrya y s.
THE non'ms PETERS co, Pummnno WASHINGTON, o, c.
NlTE rnrns FFICEQ ANDREIV SEVVERSON, OF ROSELAND, ILLINOIS.
ROTARY HARROW.
SJPECIFIGATION forming part of Letters Patent No. 566,234, dated August 18, 1896. Application filed January 2, 1895. Serial No. 533,616. (No model.)
To all whom it may concern.-
Be it known that I, ANDREW SnwERsoN, a citizen of the United States, residing at Roseland, in the county of Cook and State of Illinois, have invented a new and useful Rotary Harrow, of which the following is a specification.
The invention relates to an improvement in that class of harrows wherein the pulverizing-tools are made to engage the ground with a rotary movement; and the principal object of the invention is to improve the construction of these pulverizing-tools and to provide in place of the ordinary disks a series of radial arms which have certain peculiar features of construction whereby their efficiency is increased, and which are positively driven at a greater speed than the groundwheels by gearing them with moving parts of the machine, this forced rotation of the tools being considered more effective than where the tools merely engage and rotate idly by reason of their contact with the earth.
A further object of the invention is to provide improved means by which the driving of the pulverizing-tools may be effected, and also to make it possible to throw said tools in and out of gear by a simple and easy movement.
Further objects and advantages of this invention will appear in the following description, and the novel features thereof will be particularly pointed out in the appended claims.
In the drawings, Figure 1 represents a perspective View of my complete harrow. Fig. 2 is a vertical longitudinal section thereof. Fig. 3 is a sectional View taken parallel with the shaft upon which the pulverizing-tools are mounted and extending through the sup porting-arms of this shaft to the main axle of the machine. Fig. 4: is a detail section taken through one of the pinions which are affixed to the tool-carrying shaft, and showing the clutch devices. Fig. 5 is a detail view of the devices for throwing the pinion in and out of engagement with the driving-gear. Fig. 6 is a detail perspective illustrating the preferred means for securing the pulverizing-tools to the shaft. Fig. 7 is a sectional view illustrating a modification of these means. Fig. 8 is a detail perspective of a modified arrangement of means for throwing the pinions of the tool-carrying shaft out of engagement with their respective driving-gears. Fig. 9 is a detail plan View of a part of the frame.
Similar numerals of reference indicate corresponding parts in all the figures of the drawings.
The frame of my improved machine comprises a metallic cross-bar or casting 1, having at its extremities the rearwardly-projecting arms 2, provided with boxes 3, in which the axle 4 is mounted and is capable of rock ing movement. Projecting rearwardly from the middle of the casting 1 are similar arms 5, carrying boxes 6, through which the axle 4 also extends.
7 indicates a forwardly-proj ectin g arm pro vided with suitable flanges or ribs for receiving the tongue 8 of the machine. One of the arms 5, and preferably the left-hand arm, has an extension 9,which extends rearwardly and upwardly and is provided with flanges or ribs to engage the spring-standard 10. The standard 10 is rigidly bolted to the extension 9 and has its upper end bent to lie in a horizontal plane to support the seat 11.
12 indicates ground-wheels loosely mounted upon the ends of the axle at, the extremities of the axle being provided with collars 13, whereby the wheels are held in place. Rigidly secured to or formed integral with the wheels 12 are the internal cog-rims 14, forming driving-gears,which are provided at their outer peripheries, as illustrated in the drawings,with radial projections or arms 15,which are secured to the inner surface of the wheelrim.
Arranged 011 the rock'shaft or axle 4: contiguous to the boxes 3, are the arms 16 which have their inner ends formed with bossed openings 17, rigidly affixed to the shaft by means of pins or keys 18, which pass through the bosses and through the shaft. These arms 16 extend rearwardly from the shaft or axle to points adjacent to the driving-gears 14, where they are provided with transverselyalined openings 19 and outer flanges or bosses 20, said flanges being provided at their outer ends with annular grooves 21.
Removably mounted in the openings 19 of the arms 16 is the shaft 22, which extends parallel with the rock-shaft or axle and projects at its ends beyond the arms 16. Formed in that portion of each end of the shaft 22 which projects beyond the arm 16 is a longitudinal groove 23, in which is fitted a pawl-plate 24, having a beveled face 25. These pawl-plates 24 are actuated by bow-spring. 20, located within the grooves 24.
Mounted upon the ends of the shaft 22 are the pinions 27, to mesh with the driving-gears or cog-rims 14, and by these means to receive and transmit to the shaft 22 the movements of the wheels 12. The gears 27 have their bores formed with a series of longitudinal parallel grooves 28, triangular in cross-sectional shape to receive the beveled edges 25 of the pawl-plates 24. Thus it will be seen that the pinions 27 are mounted upon the shaft 22 for free movement in one direction, and hence the pinions will be fixed to the shaft when the machine is moving forward, and will turn loosely when the machine is moving backward. This enables the machine to be backed without causing the pulverizin g-tools to be revolved.
29 indicates two expansion-springs, which bear at their inner ends in the annular grooves 21 of the flanges 20 and at their outer ends within annular recesses 30, formed on the inner sides of the pinions 27, and by these means the said pinions are normally held in engagement with the cog-rims 14. Formed at the inner end of each pinion 27 is an in ward extension 31, having an annular groove which receives the lower arm of the lever 32, whereby the pinions may be thrown in or out of engagement with the driving-gear. The levers 32 are fulcrumed upon the brackets 33, which are in turn rigidly secured to or formed integral with the outer sides of the arms 16. The inner shortarms of the levers 32 are provided with longitudinal slots 34, in which the pins 35 of the levers 36 are slidably mounted, so that when the levers 36 swing on their fulcrums the levers 32 will be correspondingly moved. The levers 30 are fulcrumed upon the arms 16, and project upward approximately in alinement with the same. 37 indicates a segment which is adapted for engagement by the pawl 38, each lever being provided with a pawl whereby they may be independently operated.
It will be understood that a slight movement of the levers 30 will result in a su fficient movement of the long arm of the lever 32 to shift the gears 37 to the requisite extent. This is owing to the fact that a comparatively long arm on each of the levers 36 is connected to a short arm on the corresponding lever 32, which causes the long arm of the latter lever to swing with a multiplied movement.
The pulverizing-tools 39 consist of a series of collars 40, which carry radial arms 41, preferably eight for each collar, and the extremities of the arms are arranged in a common opposite directions, so that in each set of arms 41 four fingers will be bent to one side and four to the other, and the edges of both arms and fingers are sharpened. Formed integral with the inner collars and projecting out from each side thereof are the opposite extensions 43 and 44, two for each collar. The collars of the terminal tools have only one extension, projecting inwardly, the opposite side being provided with a flange 45, through which fastening screws or pins may be passed into the shaft 22. By these means the end tools are rigidly secured to the shaft. The projections or flanges 44 of all the tools 39 have their ends formed with concaved depressions or notches, which are respectively adapted to receive the correspondingly-convexed ends of the projections 43. By these means the pulveriZing-tools are rigidly mounted upon the shaft 22 without having to pierce said shaft for the reception of numerous fastening devices, which would tend to materially reduce the strength of the shaft. The end tools he in g rigid and the intermediate tools being connected thereto, all are held properly in place. Fig. 7 illustrates a modification of these devices in which the collars 40 are secured to sleeves or hollow shafts 46 and the latter are fixed to the shaft 22. This attains the end desired, but is not regarded as being as good as the extensions 43 and 44, principally for the reason that it makes the machine much heavier, and also that it increases the expense of building the machine.
Fixed to the axle 4, between the boxes (3 of the frame 1, is a mutilated gear 47, which meshes at this point with a mutilated gear 48, mounted upon a spindle 49, supported by the arms 50, which rise from the boxes 6. The gear 48 is provided with a lever 51, which is operated contiguous to a ratchet-segment 52 on the right-hand arm 50, and this segment is engaged by a pawl 53, mounted in a casing or sleeve 54, aflixed to the lever. 55 indicates a rod which is pivotally connected to the pawl 53 and which extends to a hand-lever 50, fulcrumed to said upper end of the lever 51. By means of this construction the axle 4 may be rocked in its bearings and the arms 16 correspondingly swung to raise or lower the toolshaft 22; also, by means of the ratchet 52 and pawl 53 the parts may be locked in the desired position.
It will also be observed that by means of this arrangement the depth at which the pulverizing-tools operate may be regulated, causing them to merely scrape the surface of the ground or to operate any desired depth below the surface.
Rigidly secured to the axle 4 and curving rearwardly and downwardly from the same is the shield 57, which is arc-shaped in cross section and which embraces the pulverizing tools, so as to prevent dust from arising and clods and other articles from being thrown by the tools. This shield has recesses or notches 58 formed in its ends adjacent to the arms 16 to receive the levers 36, so that the upper ends of said levers may project beyond the shield and be accessible to the operator. This shield is preferably constructed of sheet metal.
The modification illustrated in Fig. 8 consists of a bar 59, rotatably mounted in a bracket at the outer side of the arm 16. 61 indicates a pin which passes through the bar 59 and rests upon the bracket 60, to support the bar. The lower end of the bar 59 is provided with a horizontally and downwardly extending offset 62, which forms a crank, and the end of this portion is seated within the annular groove in the extension 31 of the adjacent gear 27. The upper end of the bar 59 is formed with a lateral offset 63, which is disposed obliquely from the offset or crank 62, and which is provided to furnish means for oscillating the bar 59. Thus by rocking the bar 59 the crank 62 may be made to swing, thereby throwing the gear 27 in and out of engagement with its respective cog-rim. In this arrangement the gear is not changed as to the grooves 28 and pawl-plates 24. It has, however, no spring, it being held in engagement with its respective rim It by the bar 59 and its several offsets, which operate to form a dead-center and to prevent the movement of the gear by power applied to it other than through the medium of the bar 59.
Various changes in the form, proportion, and the minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of this invention.
Having described my invention, what I claim is 1. In a harrow, the combination with a frame, and ground-wheels, of a rock-shaft mounted upon the frame and forming the axle of the ground-wheels,fixed arms carried by the rock-shaft, a tool-carrying shaft mounted in bearings at the free ends of said arms, internal drivinggears concentric with the groundwheels, pinions mounted for longitudinal movement upon the toolcarrying shaft and adapted to be arranged in or out of engagement with the driving-gears, said pinions hav ing ratchet-hubs engaged by spring-actuated pawl-plates seated in the tool-carrying shaft parallel with the axis thereof, whereby the pawl-plates are in operative relation with the ratchet-teeth in all positions of the pinions, and whereby the pinions are adapted when in engagement with the driving-gears to impart only forward rotary movement to the toolcarrying shaft, springs being employed for holding the pinions normally in engagement with the driving-gears, and means for moving the pinions against the tension of their actuating-springs to disengage them from the driving-gears, substantially as specified.
2. In a harrow, the combination with a frame, and ground-wheels, and a tool-carrying shaft mounted upon the frame and operatively connected with the ground-wheels, of terminal pulverizing-tools having collars fixed to said shaft, and intermediate pulverizingtools having collars loosely mounted upon the shaft, said fixed and loose collars being provided with interlocking projections and recesses to prevent independent rotation of the intermediate tools, substantially as specified.
In a harrow, the combination with a frame, and ground-wheels, and a revoluble tool-carrying shaft operatively connected with the ground-wheels, of terminal pulverizing-tools having collars fixed to the shaft, intermediate pulverizing-tools having collars loosely mounted on the shaft, fixed inwardlyextending projections on the terminal collars and oppositely-extending projections on the loose collars, the contiguous extremities of the projections on adjoining collars being respectively reduced and recessed to form interlocking connections whereby the intermediate tools are locked with the terminal tools to the shaft, substantially as specified.
4. In a harrow, the combination with a supporting-frame having ground-wheels, and a transverse revoluble shaft operatively con nected with the ground-Wheelspf pulverizingtools fixed to said shaft, each tool comprising a collar, a series of radial arms flattened in a plane transverse to the axis of the shaft or parallel with the forward movement of the machine, and transversely bent or deflected terminal fingers at the extremities of the arms, said fingers extending in opposite directions upon alternate arms and the edges of the arms and fingers being reduced to form cutting edges, substantially as specified.
In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two witnesses.
ANDREW SEYVERSON.
\Vitnesses FRANK E. Lovnrr, FRANK O. RoBY.
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