US1199672A - Knife-grinding machine. - Google Patents

Knife-grinding machine. Download PDF

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Publication number
US1199672A
US1199672A US84857414A US1914848574A US1199672A US 1199672 A US1199672 A US 1199672A US 84857414 A US84857414 A US 84857414A US 1914848574 A US1914848574 A US 1914848574A US 1199672 A US1199672 A US 1199672A
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grinding
knife
reversing
pulley
shaft
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US84857414A
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Joseph Dick
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JOSEPH DICK MANUFACTURING Co
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JOSEPH DICK Manufacturing Co
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B13/00Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor
    • B24B13/02Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor by means of tools with abrading surfaces corresponding in shape with the lenses to be made

Definitions

  • Knife-Grinding Machines in which the following is a specification.
  • the invention relates to a machine for grinding the beveled edge of straight knife blades used in fodder cutters, planing machines, and the like, wherein a straight edge and a true bevel are necessary or de sirable.
  • a machine for grinding the beveled edge of straight knife blades used in fodder cutters, planing machines, and the like wherein a straight edge and a true bevel are necessary or de sirable.
  • the object of the present invention is to provide a grinding machine having a stationary carrying support for the knife and a grinding wheel movin longitudinally thereof, with means for ad usting the knife support, means for automatically moving the grinding wheel to and fro endwise of the knife during the operation of the machine, and means for permitting the'grinding element to operate in a statlonary position for use in ordinary work.
  • Ancillary features of the improvement relate to improved means for transmitting .power from a relatively stationary main shaft to the oscillating shaft of the grinding element; to improved means for reversing themovement of the grinding element at the ends of its oscillation, and for holding the reversing means against accidental operation; and to means actuated by the rotation.
  • FIG. 1 A preferred embodiment of the invention is illustrated in the accompanying drawings forming part hereof, in which' Figurcl is a perspective view of the knife grinding machine; Fig. 2, an end view of the same; Fig. 3, a front elevation of the same; Fig. 4, a section of the grinding head and carrier; Fig. 5, a plan view of the knife grinding machine; Flg. 6, adetached plan view of the reversing bar; Fig. 7 asimilar view illustrating the operation of the revers- 1ng bar; Fig. 8, adetached elevation of the belt transmission gearing illustrating the movements thereof; Fig. 9, a fragmentary elevation, partly in section, of the clutch pulley; Fig. 10, a detached perspective view of the clutch lever; Fig. 11, afragmentary rear View showing the clutch, its lever and its, bearlng; and Fig; 12, a rear perspective view of the blast nozzle.
  • the grinding machine includes the frame 1, the cross heads 2 and 2 secured on the ends of the frame, the knife holder3 secured by the adjusting arms 4 to the cross heads, slide bars 5 and 5- extending between and having their ends secured to the cross heads,
  • the grinding head 6- mounted on the slide bars, the grinding wheel 7 having its spindle 8 j ournaled in the grinding head, them'ain pulley 9 on the main shaft 10, the belt gear 11 for the grinding spindle, the bevel gearmg; 12 for the clutch shaft 13, the clutch pulley 14:,the reversing belts 15 and 15*, the
  • the arms 4 for the knife support 3 are adjusted forward and rearward by means of the screw' heads 20 and the compresslon V springs 21 located on these arms between the pendent bearings 22 and 22 on the cross heads, in which the. arms are-mounted; so that 'theknife holder 3 may be adjusted to and from the grinding edge 23, ofthe face of the grinding wheel 7, and the springs will cushion the movement of the supporting arms in one direction. It 'will be under stood that the work of grinding is performed by one peripheral edge only of the grinding wheel, in the manner well known v v in the art; the knife 24 being secured to the supports 3 bythe clamps 25.
  • the main. shaft 10 is journaled in the.
  • the upper end of the oscillating arm 31 is bent L shaped to the side opposite the grinding spindle 8, with which spindle it is connected by the link 32 pivoted at one end to the grinding spindle and at the other end to the angle of the l. shaped arm 31 between the pivots of the idle pulleys thereon.
  • the construction and arrangement of these parts serves to carry the idle pulleys 29 and 30 in proper relative position to hold the belt gear 11 taut in all the varying positions of the grinding spindle, as it moves to and fro with the grinding head upon the slide bars; which varying positions of the pulleys is shown by broken lines in Fig. 8.
  • This head is provided with the socket 43 normally receiving the stops 36 on the end of the pulley, and is also provided with the cam faces 44, cotiperating withthe lugs 45 I on the side of the bearing, so that a rotation of the clutch arm 34- will move the cam head and the clutch pulley endwise upon the
  • the grinding head 6 is mounted on the slide rods 5 and 5* by means of the slide 'while the other belt travels on one of the idle wheels 17 or 17 located one on each side of the pulley 16.
  • the reversing belts are shifted from one pulley to another, by the reversing rod 19, which has endwise movements in bearings 49 in the cross heads.
  • Reversing stops 50 and 50 are adjustably secured on the end portions of the reversing bar, which stops have yoked fingers 51 and 51*, extending upward around the screw shaft 18 in the path of the screw bearing 49; and the parts are so arranged that when the grinding head is carried in one direction, the screw bearing thereon impinges the stop fingers of the corresponding reversing stop, and moves the reversing rod 19 endwise, which movement shifts one reversing belt from and the other reversing belt upon the reversing pulley 16, by means of the looped arms 52 and 52 which engage the respective belts.
  • the grinding head is carried by the worm gear toward one end of the frame the stop fingers on the reversing rod are impinged by the screw bearing, and the reversing rod is carried endwise with the grinding head until the end of the spring 53 is forced outward by the pivoted link 55 and this link assumes a position perpendicular to the reversing rod; after which a further endwise movement of the reversing rod car ries the link beyond the perpendicular position, whereupon the energy of the spring, acting through the link, thrusts the reversing rod endwise to bring the proper belt fully upon the reversing pulley .to reverse the rotation of the same; after which the spring 53, acting through the link 57, holds the reversing rod and the corresponding belt in this position until the grinding head approaches the other end of the machine, whereupon a similar reversing operation is repeated.
  • the fan case 58 is formed or secured on the grinding head 6, preferably adjacent to the inner slde of the grinding wheel, and
  • the centrifugal fan 59 is secured to the grinding spindle 8 within the fan case.
  • the flexible tube 60 is connected at one end to the outlet 61 of the fan case, and at the other end to the blast nozzle 62, which in .turn is supported by the rod 63 having endwise adjustment in the bearing 64. formed or secured on the grinding head.
  • the blast nozzle 62 is bent to bring its free end adjacent to and parallel with the grinding edge 23 of the rim of the grinding wheel 7; and this end is preferably provided with the longitudinal slot 65, so positioned as to discharge a blast of air against the grinding edge of the wheel and the edge of the knife where the same is being ground, for
  • a grinding machine including a knife support, a grinding Wheel, means for operating the grinding wheel, cooperating means connected with the operating means for moving the grinding wheel endwise of the knife support, and means for disconnecting the cooperating means.
  • a grinding machine includin an oscillating grinding spindle, a relative y stationary main shaft, and a gearing including pulleys secured on the shaft and on the spindle, an oscillating arm pivoted on the shaft having an angle on its oscillating end, idle pulleys pivoted on the arm on opposite sides of the angle, a link pivoted to the axis of the grinding means and to the angle of the oscillating arm, and a belt on the pulleys.
  • a grinding machine including oscillatinggrinding means having a screw bearing therein, a screw shaft operating in the screw bearing to oscillate the grinding means, reversing transmission gearing for the screw shaft, an endwise movable. reversing rod having stops thereon in the path of the grinding means and having controlling engagement with the reversing gearing, a spring, and a link connecting the spring with the reversing rod for thrusting and holding the rod in one direction when the rod has been moved from the opposite direction to carry the link beyond a perpendicular position.
  • a grinding machine including an ostionary main shaft, and a gearing including pulleys secured on the shaft and on the spindle, an oscillating arm pivoted on the shaft, an idle pulley pivoted to the free end of the arm, another idle pulley pivoted on the arm intermediate its ends, a link pivoted to the axis of the grinding means andto the oscillating arm at one side of the plane passing through the pivots of the idle pulleys, and a belt on the pulleys.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Description

J. DICK.
' KNIFE GRINDING MACH INE. APPLICATION FILED JULY 2, 19M.
1 1 99,672 I Patent-ed Sept. 26, 1916.
4 SHEETS-SHEET l.
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Wig M6868; I f j pg zfar cjjwua Jose kick (flaw-CM y 1 anzey J. DICK.
KNIFE GRINDING MACHINE.
APPLICATION FILED JULY 2. 19:4.
Patented Sept. 26, 1916.
4 SHEETS-SHEET 2 Ziorzze'y.
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J. DICK.
KNIFE GRINDING MACHINE.
v. A1}|.MIII. Q LIW 4 SHEETS-SHEET 3.
J'nue/zzaz'. Jbse vh/Dp'a/a Patent-ed Sept. 26, 1916.
APPLICATION FILED JULY 2- 1914.
m EINH J. DICK.
KNIFE GRINDING MACHINE;
APPLICATION FILED JULY 2.1914.
Patented Sept. 26, 1916.
4 SHEETS-SHEET 4.
K Mum In var/Liar. J6 se v kl? z' 0/0.
JOSEPH DICK, OF CANTON, OHIO, ASSIGNOR TO THE JOSEPH DICK MANUFACTURING COMPANY, OF CANTON, OHIO, A CORPORATION OF OHIO.
KNIFE-GRINDING MACHINE.
Specification of Letters Patent.
Patented Sept. 26, 11916.
To all whom it may concern .1
Be it known that I, JOSEPH DICK, a citizen of the United States, residing at Canton,
in the county of Stark and State'of Ohio, have invented certain new and useful Improvements in Knife-Grinding Machines, of which the following is a specification.
The invention relates to a machine for grinding the beveled edge of straight knife blades used in fodder cutters, planing machines, and the like, wherein a straight edge and a true bevel are necessary or de sirable. When such a knife is ground by applying it manually to the face of a grinding element, it is difficult, if not impossible, to grind a straight edge and a uniform bevel, and when a supporting frame for the knife is required to move endwise with respect to a relatively stationary grinding element, the machine requires so much space as to render it impractlcal or inconvenient for many kinds of use. p
The object of the present invention is to provide a grinding machine having a stationary carrying support for the knife and a grinding wheel movin longitudinally thereof, with means for ad usting the knife support, means for automatically moving the grinding wheel to and fro endwise of the knife during the operation of the machine, and means for permitting the'grinding element to operate in a statlonary position for use in ordinary work.
Ancillary features of the improvement relate to improved means for transmitting .power from a relatively stationary main shaft to the oscillating shaft of the grinding element; to improved means for reversing themovement of the grinding element at the ends of its oscillation, and for holding the reversing means against accidental operation; and to means actuated by the rotation.
of the grinding means for cooling the grindin wheel and the knife blade during the grinding operation.
A preferred embodiment of the invention is illustrated in the accompanying drawings forming part hereof, in which' Figurcl is a perspective view of the knife grinding machine; Fig. 2, an end view of the same; Fig. 3, a front elevation of the same; Fig. 4, a section of the grinding head and carrier; Fig. 5, a plan view of the knife grinding machine; Flg. 6, adetached plan view of the reversing bar; Fig. 7 asimilar view illustrating the operation of the revers- 1ng bar; Fig. 8, adetached elevation of the belt transmission gearing illustrating the movements thereof; Fig. 9, a fragmentary elevation, partly in section, of the clutch pulley; Fig. 10, a detached perspective view of the clutch lever; Fig. 11, afragmentary rear View showing the clutch, its lever and its, bearlng; and Fig; 12, a rear perspective view of the blast nozzle.
Similar numerals refer to similar parts throughout the drawings.
The grinding machine includes the frame 1, the cross heads 2 and 2 secured on the ends of the frame, the knife holder3 secured by the adjusting arms 4 to the cross heads, slide bars 5 and 5- extending between and having their ends secured to the cross heads,
the grinding head 6- mounted on the slide bars, the grinding wheel 7 having its spindle 8 j ournaled in the grinding head, them'ain pulley 9 on the main shaft 10, the belt gear 11 for the grinding spindle, the bevel gearmg; 12 for the clutch shaft 13, the clutch pulley 14:,the reversing belts 15 and 15*, the
- reversing pulley 16 and the idle pulleys 17 and 17 on the worm gear 18 which is journaled in the cross heads, andthe reversing, rod 19 which is mounted longitudinally on the frame. I
The arms 4 for the knife support 3 are adjusted forward and rearward by means of the screw' heads 20 and the compresslon V springs 21 located on these arms between the pendent bearings 22 and 22 on the cross heads, in which the. arms are-mounted; so that 'theknife holder 3 may be adjusted to and from the grinding edge 23, ofthe face of the grinding wheel 7, and the springs will cushion the movement of the supporting arms in one direction. It 'will be under stood that the work of grinding is performed by one peripheral edge only of the grinding wheel, in the manner well known v v in the art; the knife 24 being secured to the supports 3 bythe clamps 25.
The main. shaft 10 is journaled in the.
' bearing 26 secured in fixed relation to the frame substantially midway between the ends thereof; and power received-by this shaft from the main pulley 9, is transmitted to the grinding spindle 8 by means of the belt gear 11 whlch passes around the pulleys 27 on. the'main shaft, .the pulley 28 on the grinding spindle, .and the idle pulleys 29 and 30 journaled on the oscillating arm 31 which rises from a pivotal connection with the main shaft 10.
The upper end of the oscillating arm 31 is bent L shaped to the side opposite the grinding spindle 8, with which spindle it is connected by the link 32 pivoted at one end to the grinding spindle and at the other end to the angle of the l. shaped arm 31 between the pivots of the idle pulleys thereon. The construction and arrangement of these parts serves to carry the idle pulleys 29 and 30 in proper relative position to hold the belt gear 11 taut in all the varying positions of the grinding spindle, as it moves to and fro with the grinding head upon the slide bars; which varying positions of the pulleys is shown by broken lines in Fig. 8.
Power is transmitted from the main shaft 10 by the bevel gearing 12 and the clutchv shaft 13 to the clutch pulley 14, rotatably mounted on the clutch shaft 13, which inturn is journaled in the sleeve 33, on the clutch arm 34, which sleeve has endwise movement in the pendent bearing 35, depending from the frame. One end of the clutch pulley 12 is provided with the ratchet stops 36 adapted to engage the cross pin 37. on the clutch shaft 13, and the transverse wall 38 in the clutch pulley is abutted by the compression spring 39 which in turn abuts the collar 40, secured on the clutch shaft; whereby the pulley is normally held terposed between the pendent bearing 35 and the adjacent end of the clutch pulley. This head is provided with the socket 43 normally receiving the stops 36 on the end of the pulley, and is also provided with the cam faces 44, cotiperating withthe lugs 45 I on the side of the bearing, so that a rotation of the clutch arm 34- will move the cam head and the clutch pulley endwise upon the The grinding head 6 is mounted on the slide rods 5 and 5* by means of the slide 'while the other belt travels on one of the idle wheels 17 or 17 located one on each side of the pulley 16. The reversing belts are shifted from one pulley to another, by the reversing rod 19, which has endwise movements in bearings 49 in the cross heads.
Reversing stops 50 and 50 are adjustably secured on the end portions of the reversing bar, which stops have yoked fingers 51 and 51*, extending upward around the screw shaft 18 in the path of the screw bearing 49; and the parts are so arranged that when the grinding head is carried in one direction, the screw bearing thereon impinges the stop fingers of the corresponding reversing stop, and moves the reversing rod 19 endwise, which movement shifts one reversing belt from and the other reversing belt upon the reversing pulley 16, by means of the looped arms 52 and 52 which engage the respective belts.
The action of the reversing rod is rendered positive and certain, and the proper belt is maintained upon the reversing pulley 16, by means of the spring 53 having one end secured to the frame by the bracket 54, and the other end connected to the reversing rod 19, by the link 55, the resilience of the spring normally pressing the pivoted end of the link inward toward and in contact with the reversing rod, as shown in Fig. 6.
Then the grinding head is carried by the worm gear toward one end of the frame the stop fingers on the reversing rod are impinged by the screw bearing, and the reversing rod is carried endwise with the grinding head until the end of the spring 53 is forced outward by the pivoted link 55 and this link assumes a position perpendicular to the reversing rod; after which a further endwise movement of the reversing rod car ries the link beyond the perpendicular position, whereupon the energy of the spring, acting through the link, thrusts the reversing rod endwise to bring the proper belt fully upon the reversing pulley .to reverse the rotation of the same; after which the spring 53, acting through the link 57, holds the reversing rod and the corresponding belt in this position until the grinding head approaches the other end of the machine, whereupon a similar reversing operation is repeated.
The fan case 58 is formed or secured on the grinding head 6, preferably adjacent to the inner slde of the grinding wheel, and
. the centrifugal fan 59, is secured to the grinding spindle 8 within the fan case. The flexible tube 60 is connected at one end to the outlet 61 of the fan case, and at the other end to the blast nozzle 62, which in .turn is supported by the rod 63 having endwise adjustment in the bearing 64. formed or secured on the grinding head. The blast nozzle 62 is bent to bring its free end adjacent to and parallel with the grinding edge 23 of the rim of the grinding wheel 7; and this end is preferably provided with the longitudinal slot 65, so positioned as to discharge a blast of air against the grinding edge of the wheel and the edge of the knife where the same is being ground, for
cooling the same; it being understood that the same rotation of the grinding spindle which turns the grinding wheel, also rotates the centrifugal fan for creating the cooling 7 blast of air.
' moving the grinding wheel-endwise of the the side of the grinding wheels.
2. A grinding machine including a knife support, a grinding Wheel, means for operating the grinding wheel, cooperating means connected with the operating means for moving the grinding wheel endwise of the knife support, and means for disconnecting the cooperating means.
3. A grinding machine-including a knife support, a grinding wheel, means for operating the grinding wheel, cooperating means connected with the operating means for cillating grinding spindle, a relatively staknife support, and means for releasing the cooperating means when the operating means turn in one direction only.
4. A grinding machine includin an oscillating grinding spindle, a relative y stationary main shaft, and a gearing including pulleys secured on the shaft and on the spindle, an oscillating arm pivoted on the shaft having an angle on its oscillating end, idle pulleys pivoted on the arm on opposite sides of the angle, a link pivoted to the axis of the grinding means and to the angle of the oscillating arm, and a belt on the pulleys.
5. A grinding machine including oscillatinggrinding means having a screw bearing therein, a screw shaft operating in the screw bearing to oscillate the grinding means, reversing transmission gearing for the screw shaft, an endwise movable. reversing rod having stops thereon in the path of the grinding means and having controlling engagement with the reversing gearing, a spring, and a link connecting the spring with the reversing rod for thrusting and holding the rod in one direction when the rod has been moved from the opposite direction to carry the link beyond a perpendicular position. v
6. A grinding machine including an ostionary main shaft, and a gearing including pulleys secured on the shaft and on the spindle, an oscillating arm pivoted on the shaft, an idle pulley pivoted to the free end of the arm, another idle pulley pivoted on the arm intermediate its ends, a link pivoted to the axis of the grinding means andto the oscillating arm at one side of the plane passing through the pivots of the idle pulleys, and a belt on the pulleys. Y
Y 1 JOSEPH DICK. Witnesses:
HARRY FREASE, FEED J. ZETTLER.
US84857414A 1914-07-02 1914-07-02 Knife-grinding machine. Expired - Lifetime US1199672A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4532735A (en) * 1982-04-26 1985-08-06 Dahlgren Manufacturing Company Variable angle extruder blade surfacing machine
US4727683A (en) * 1987-01-09 1988-03-01 Dynabrade, Inc. Abrasive belt machine
US4845900A (en) * 1986-12-25 1989-07-11 Kabushiki Kaisha Taihei Seisakusho Method and apparatus for grinding straight-edged cutting tools to a fine finish
US5233792A (en) * 1990-11-26 1993-08-10 Kabushiki Kaisha Taihei Seisakusho Apparatus for superfinishing cutting edges
US6908373B1 (en) * 2002-11-26 2005-06-21 Larry S. Ohman Shear blade sharpener method and apparatus

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4532735A (en) * 1982-04-26 1985-08-06 Dahlgren Manufacturing Company Variable angle extruder blade surfacing machine
US4845900A (en) * 1986-12-25 1989-07-11 Kabushiki Kaisha Taihei Seisakusho Method and apparatus for grinding straight-edged cutting tools to a fine finish
US4984394A (en) * 1986-12-25 1991-01-15 501 Kirin Beer Kabushikikaisha Method and apparatus for grinding straight-edged cutting tools to a fine finish
US4727683A (en) * 1987-01-09 1988-03-01 Dynabrade, Inc. Abrasive belt machine
US5233792A (en) * 1990-11-26 1993-08-10 Kabushiki Kaisha Taihei Seisakusho Apparatus for superfinishing cutting edges
US6908373B1 (en) * 2002-11-26 2005-06-21 Larry S. Ohman Shear blade sharpener method and apparatus
US6955590B1 (en) * 2002-11-26 2005-10-18 Davis Francis R Ice resurfacing blade sharpener

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