US3748052A - Adjustable high speed bit - Google Patents

Adjustable high speed bit Download PDF

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Publication number
US3748052A
US3748052A US00165450A US3748052DA US3748052A US 3748052 A US3748052 A US 3748052A US 00165450 A US00165450 A US 00165450A US 3748052D A US3748052D A US 3748052DA US 3748052 A US3748052 A US 3748052A
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United States
Prior art keywords
blades
plate
shank
flat plate
blade
Prior art date
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
Application number
US00165450A
Inventor
I Jensen
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BRIT JEN TOOL CO Inc
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BRIT JEN TOOL CO Inc
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Publication of US3748052A publication Critical patent/US3748052A/en
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Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23B—TURNING; BORING
    • B23B51/00—Tools for drilling machines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27G—ACCESSORY MACHINES OR APPARATUS FOR WORKING WOOD OR SIMILAR MATERIALS; TOOLS FOR WORKING WOOD OR SIMILAR MATERIALS; SAFETY DEVICES FOR WOOD WORKING MACHINES OR TOOLS
    • B27G15/00—Boring or turning tools; Augers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23B—TURNING; BORING
    • B23B2251/00—Details of tools for drilling machines
    • B23B2251/14—Configuration of the cutting part, i.e. the main cutting edges
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23B—TURNING; BORING
    • B23B2260/00—Details of constructional elements
    • B23B2260/004—Adjustable elements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23B—TURNING; BORING
    • B23B2260/00—Details of constructional elements
    • B23B2260/088—Indication scales
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T408/00—Cutting by use of rotating axially moving tool
    • Y10T408/86—Tool-support with means to permit positioning of the Tool relative to support
    • Y10T408/865—Pivotable Tool
    • Y10T408/868—Pivotable Tool with multiple cutting positions
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T408/00—Cutting by use of rotating axially moving tool
    • Y10T408/89—Tool or Tool with support
    • Y10T408/905—Having stepped cutting edges
    • Y10T408/906—Axially spaced

Definitions

  • An adjustable high speed wood bit adapted for use with I an electric drill and having a long cylindrical shank with a flat blade integrally formed on the lower end thereof.
  • the flat blade has a point on its lower end for centering the drill and forming a pilot hole.
  • the lower edges of the flat plate alongside of the point are oppositely sharpened to cut the wood in forming a bore.
  • a pair of blades are pivotally secured to opposite sides of the flat plate with each blade having a slot partially overlying a vertical slot in the blade.
  • a bolt extends through the three slots and may be raised and lowered in the vertical slot of the flat plate to cause the blades to swing outwardly increasing the diameter of the bit, The lower edges of the blades are sharpened to cut the wood in forming a bore.
  • the bolt securely fastens the blades in adjusted position during the cutting operation.
  • a scale is formed on the flat plate to cooperate with the side edge of one of the blades to indicate the size of the bore which will be-drilled by thebit in a specific adjusted arrangement.
  • an elongate cylindrical shaft has a relatively flat plate integrally formed on its lower end carrying an axial point for forming a pilot hole in the material being drilled.
  • the lower edges of the flat plate on opposite sides of the point are oppositely sharpened to permit the flat plate to act as a cutter when rotated in an electric drill.
  • a pair of cutter blades are secured at their upper end portions by a rivet to the upper end portion of the plate with each blade having an oppositely extending slot partially overlying a vertical slot formed centrally of the plate.
  • a bolt extends through the three slots to secure the blades to the plate in radially adjusted position for boring the desired size hole in wood. Movement of the bolt in the vertical slot causes the blades to swing outwardly on their pivots.
  • the primary object of the invention is to provide an adjustable high speed drill bit which can be expanded to drill holes of any desired size within a specific range of sizes'with the adjustment relatively simple to make.
  • FIG. 1 is a front elevation of the invention with the cutter blades in retracted position
  • FIG. 2 is a side elevation of the structure shown in FIG. 1;
  • FIG. 3 is a view similar to FIG. 1 with the cutter blades in extended position
  • FIG. 4 is a bottom plan view of the FIG. 1 construction.
  • FIG. 5 is a bottom plan view of the bit with cutters extended, as shown in FIG. 3.
  • the reference numeral I0 indicates generally an adjustable high speed wood bit constructed in accordance with the invention.
  • the wood bit includes an elongate cylindrical shaft 11 having a generally flat blade 12 integrally secured to the lower end thereof.
  • the blade 12 has parallel side edges l3, l4 and a sharpened bottom edge 15.
  • a triangular point 16 is integrally formed with the plate 12 and is symmetrical with the axis of the shaft 1 l.
  • the point 16 has its opposite sides sharpened at I7, 18 for wood cutting purposes.
  • a slot 19 is formed in the plate 12 symmetrical with the axis of the shaft 1 l and in the upper portion of the plate 12.
  • a cutting blade 20 is pivotally secured to each side of the plate 12 by means of a rivet 21 which extends through the upper portion of the blades 20 and the upper portion of the plate 12.
  • a slot 22 is formed in each of the blades 20 and slopes inwardly and downwardly from a point adjacent one side edge of the blade 20 to a point adjacent the central line thereof.
  • a bolt 23 extends through the slots 22 and the slot 19 and has a wing nut 24 provided for tightening the bolt 23 against the blades 20 to bind them in adjusted position to the plate 12.
  • the plate I2 on one side thereof adjacent the bottom is provided with indicia 25 forming a scale which cooperates with one side edge of one of the blades 20 to indicate the size of the bore that the bit will drill in its adjusted position.
  • the lower edge 26 of the blades 20 is slightly arcuate and is sharpened to permit the blades 20 to cut wood in forming a bore of a size larger than the plate I2.
  • the wing nut 24 is loosened and the blades 20 are swung in and out by moving the bolt 23 until the desired bore size is indicated by one edge of the blade 20 cooperating with the scale 25.
  • the wing nut 24 is then tightened on the bolt 23, binding the blades 20 to the plate 12 in angularly adjusted position.
  • the bit 10 is then used in the conventional manner to drill a bore in wood, plastic, fiber glass, formiea, and the like.
  • the cutting blades 20 are swung in to overlie the plate 12 by first loosening the bolt 23 and then tightening the same with wing nut 24.
  • An adjustable high speed bit for electric drills comprising a'generally cylindrical shank, a flat plate integrally secured to said shank and extending from the lower end thereof with spaced parallel side edges, a sharpened cutting edge formed on the lower edge of said plate, a cutting point integrally formed centrally of the lower edge of said plate symmetrical about the axis of said shank, a pair of cutter blades on opposite sides of said plate, said cutter blades having lower arcuate edges, a rivet pivotally securing the upper end portion of each of said blades to the upper end portion of said plate along the axis of said shank, means for adjustably securing said blades to said plate, and means including a scale on said plate for setting said blades for the desired circumference of cut.
  • the means for securing said blades in adjusted-position on said plate includes a vertical slot extending through said plate along the axis of said shank, and a pair of angularly related slots and a clamping bolt extending through said slots for clamping said blades to said plate.

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Forests & Forestry (AREA)
  • Drilling Tools (AREA)
  • Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)

Abstract

An adjustable high speed wood bit adapted for use with an electric drill and having a long cylindrical shank with a flat blade integrally formed on the lower end thereof. The flat blade has a point on its lower end for centering the drill and forming a pilot hole. The lower edges of the flat plate alongside of the point are oppositely sharpened to cut the wood in forming a bore. A pair of blades are pivotally secured to opposite sides of the flat plate with each blade having a slot partially overlying a vertical slot in the blade. A bolt extends through the three slots and may be raised and lowered in the vertical slot of the flat plate to cause the blades to swing outwardly increasing the diameter of the bit. The lower edges of the blades are sharpened to cut the wood in forming a bore. The bolt securely fastens the blades in adjusted position during the cutting operation. A scale is formed on the flat plate to cooperate with the side edge of one of the blades to indicate the size of the bore which will be drilled by the bit in a specific adjusted arrangement.

Description

United States Patent 1 Jensen ADJUSTABLE HIGH SPEED BIT [75] Inventor: Iwer F. Jensen, Port Clinton, Ohio [73] Assignee: Brit-Jen Tool Co., Inc., Lakeside,
} Ohio- [22] Filed: July 23, 1971 [2l] App]. No.: 165,450
.1451 July 24, 1973 s71 ABSTRACT An adjustable high speed wood bit adapted for use with I an electric drill and having a long cylindrical shank with a flat blade integrally formed on the lower end thereof. The flat blade has a point on its lower end for centering the drill and forming a pilot hole. The lower edges of the flat plate alongside of the point are oppositely sharpened to cut the wood in forming a bore. A pair of blades are pivotally secured to opposite sides of the flat plate with each blade having a slot partially overlying a vertical slot in the blade. A bolt extends through the three slots and may be raised and lowered in the vertical slot of the flat plate to cause the blades to swing outwardly increasing the diameter of the bit, The lower edges of the blades are sharpened to cut the wood in forming a bore. The bolt securely fastens the blades in adjusted position during the cutting operation. A scale is formed on the flat plate to cooperate with the side edge of one of the blades to indicate the size of the bore which will be-drilled by thebit in a specific adjusted arrangement.
4 Claims, 5 Drawing Figures PAIENInJuL24ma 1 ADJUSTABLE HIGH SPEED BIT BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION The present invention relates to adjustable high speed wood bits.
2. SUMMARY OF THE INVENTION In the present invention an elongate cylindrical shaft has a relatively flat plate integrally formed on its lower end carrying an axial point for forming a pilot hole in the material being drilled. The lower edges of the flat plate on opposite sides of the point are oppositely sharpened to permit the flat plate to act as a cutter when rotated in an electric drill. A pair of cutter blades are secured at their upper end portions by a rivet to the upper end portion of the plate with each blade having an oppositely extending slot partially overlying a vertical slot formed centrally of the plate. A bolt extends through the three slots to secure the blades to the plate in radially adjusted position for boring the desired size hole in wood. Movement of the bolt in the vertical slot causes the blades to swing outwardly on their pivots.
The primary object of the invention is to provide an adjustable high speed drill bit which can be expanded to drill holes of any desired size within a specific range of sizes'with the adjustment relatively simple to make.
Other objects and advantages will become apparent in the following specification when considered in the light of the attached drawing:
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevation of the invention with the cutter blades in retracted position;
FIG. 2 is a side elevation of the structure shown in FIG. 1;
FIG. 3 is a view similar to FIG. 1 with the cutter blades in extended position;
FIG. 4 is a bottom plan view of the FIG. 1 construction; and
FIG. 5 is a bottom plan view of the bit with cutters extended, as shown in FIG. 3.
Referring now to the drawings in detail wherein like reference characters indicate like parts throughout the several figures, the reference numeral I0 indicates generally an adjustable high speed wood bit constructed in accordance with the invention.
The wood bit includes an elongate cylindrical shaft 11 having a generally flat blade 12 integrally secured to the lower end thereof. The blade 12 has parallel side edges l3, l4 and a sharpened bottom edge 15. A triangular point 16 is integrally formed with the plate 12 and is symmetrical with the axis of the shaft 1 l. The point 16 has its opposite sides sharpened at I7, 18 for wood cutting purposes.
A slot 19 is formed in the plate 12 symmetrical with the axis of the shaft 1 l and in the upper portion of the plate 12.
A cutting blade 20 is pivotally secured to each side of the plate 12 by means of a rivet 21 which extends through the upper portion of the blades 20 and the upper portion of the plate 12. A slot 22 is formed in each of the blades 20 and slopes inwardly and downwardly from a point adjacent one side edge of the blade 20 to a point adjacent the central line thereof.
A bolt 23 extends through the slots 22 and the slot 19 and has a wing nut 24 provided for tightening the bolt 23 against the blades 20 to bind them in adjusted position to the plate 12.
The plate I2 on one side thereof adjacent the bottom is provided with indicia 25 forming a scale which cooperates with one side edge of one of the blades 20 to indicate the size of the bore that the bit will drill in its adjusted position.
The lower edge 26 of the blades 20 is slightly arcuate and is sharpened to permit the blades 20 to cut wood in forming a bore of a size larger than the plate I2.
In the use and operation of the invention, the wing nut 24 is loosened and the blades 20 are swung in and out by moving the bolt 23 until the desired bore size is indicated by one edge of the blade 20 cooperating with the scale 25. The wing nut 24 is then tightened on the bolt 23, binding the blades 20 to the plate 12 in angularly adjusted position. The bit 10 is then used in the conventional manner to drill a bore in wood, plastic, fiber glass, formiea, and the like. Following the use of the bit 10, the cutting blades 20 are swung in to overlie the plate 12 by first loosening the bolt 23 and then tightening the same with wing nut 24.
Having thus described the preferred embodiment of the invention, it should be understood that numerous structural modifications and adaptations may be resorted to without departing from the spirit of the invention.
I. An adjustable high speed bit for electric drills comprising a'generally cylindrical shank, a flat plate integrally secured to said shank and extending from the lower end thereof with spaced parallel side edges, a sharpened cutting edge formed on the lower edge of said plate, a cutting point integrally formed centrally of the lower edge of said plate symmetrical about the axis of said shank, a pair of cutter blades on opposite sides of said plate, said cutter blades having lower arcuate edges, a rivet pivotally securing the upper end portion of each of said blades to the upper end portion of said plate along the axis of said shank, means for adjustably securing said blades to said plate, and means including a scale on said plate for setting said blades for the desired circumference of cut.
2. A device as claimed in claim 1, wherein the means for securing said blades in adjusted-position on said plate includes a vertical slot extending through said plate along the axis of said shank, and a pair of angularly related slots and a clamping bolt extending through said slots for clamping said blades to said plate.
3. A device as claimed in claim 2, wherein said clamping bolt has a hand actuatable wing nut associated therewith.
4. A device as claimed in claim I, wherein the lower arcuate edge of said cutting blades is sharpened to a cutting edge.
t i i t i

Claims (4)

1. An adjustable high speed bit for electric drills comprising a generally cylindrical shank, a flat plate integrally secured to said shank and extending from the lower end thereof with spaced parallel side edges, a sharpened cutting edge formed on the lower edge of said plate, a cutting point integrally formed centrally of the lower edge of said plate symmetrical about the axis of said shank, a pair of cutter blades on opposite sides of said plate, said cutter blades having lower arcuate edges, a rivet pivotally securing the upper end portion of each of said blades to the upper end portion of said plate along the axis of said shank, means for adjustably securing said blades to said plate, and means including a scale on said plate for setting said blades for the desired circumference of cut.
2. A device as claimed in claim 1, wherein the means for securing said blades in adjusted position on said plate includes a vertical slot extending through said plate along the axis of said shank, and a pair of angularly related slots and a clamping bolt extending through said slots for clamping said blades to said plate.
3. A device as claimed in claim 2, wherein said clamping bolt has a hand actuatable wing nut associated therewith.
4. A device as claimed in claim 1, wherein the lower arcuate edge of said cutting blades is sharpened to a cutting edge.
US00165450A 1971-07-23 1971-07-23 Adjustable high speed bit Expired - Lifetime US3748052A (en)

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0008622A1 (en) * 1978-07-05 1980-03-19 HILTI Aktiengesellschaft Drilling tool for making undercuttings
US4512691A (en) * 1983-05-19 1985-04-23 The Singer Company Pilot adaptor for flat wood boring bits
US6354773B1 (en) 2000-07-27 2002-03-12 Ideal Industries, Inc. Wood boring drill bit
RU2189305C2 (en) * 1995-10-12 2002-09-20 Роберт Бош Гмбх Detachable tool and attachment for securing it in electric machines with drilling and(or) perforating mode
US20070092348A1 (en) * 2005-10-20 2007-04-26 Durfee Laverne R Spade bit
US20080101879A1 (en) * 2006-10-31 2008-05-01 Durfee Laverne R Spade-type bit
US20080202780A1 (en) * 2007-02-28 2008-08-28 Reiter John P Power Drill Accessory for Loosening Soil
CN104339423A (en) * 2014-10-24 2015-02-11 浙江博泰家具有限公司 Drilling machine for furniture board material
CN106270662A (en) * 2015-06-03 2017-01-04 襄阳三鹏航空科技有限公司 Curved surface opens circular hole device
USD863384S1 (en) * 2018-04-30 2019-10-15 Disston Company Spade drill bit
CN110682391A (en) * 2019-09-12 2020-01-14 广东韶钢工程技术有限公司 Manufacturing method and application of cast lost foam wood drill bit
USD931917S1 (en) * 2020-04-18 2021-09-28 Danyang Linrui Tools Co., Ltd. Drill

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN210025632U (en) * 2018-10-26 2020-02-07 博世电动工具（中国）有限公司 Spade drill and cordless hand-held electric tool

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US112063A (en) * 1871-02-21 Improvement in auger-bits
US737501A (en) * 1903-01-27 1903-08-25 Charles F Seblom Extension-bit.
US2794468A (en) * 1952-12-04 1957-06-04 Millers Falls Co Woodcutting bit assembly

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US112063A (en) * 1871-02-21 Improvement in auger-bits
US737501A (en) * 1903-01-27 1903-08-25 Charles F Seblom Extension-bit.
US2794468A (en) * 1952-12-04 1957-06-04 Millers Falls Co Woodcutting bit assembly

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0008622A1 (en) * 1978-07-05 1980-03-19 HILTI Aktiengesellschaft Drilling tool for making undercuttings
US4512691A (en) * 1983-05-19 1985-04-23 The Singer Company Pilot adaptor for flat wood boring bits
RU2189305C2 (en) * 1995-10-12 2002-09-20 Роберт Бош Гмбх Detachable tool and attachment for securing it in electric machines with drilling and(or) perforating mode
US6354773B1 (en) 2000-07-27 2002-03-12 Ideal Industries, Inc. Wood boring drill bit
US20110150588A1 (en) * 2005-10-20 2011-06-23 Irwin Industrial Tool Company Spade bit
US20070092348A1 (en) * 2005-10-20 2007-04-26 Durfee Laverne R Spade bit
US8147174B2 (en) 2005-10-20 2012-04-03 Irwin Industrial Tool Company Spade bit
US20080279647A1 (en) * 2005-10-20 2008-11-13 Irwin Industrial Tool Company Spade bit
US7473056B2 (en) 2005-10-20 2009-01-06 Irwin Industrial Tool Company Spade bit
US20100104387A1 (en) * 2005-10-20 2010-04-29 Irwin Industrial Tool Company Spade bit
US7905690B2 (en) 2005-10-20 2011-03-15 Irwin Industrial Tool Company Spade bit
US7922429B2 (en) 2005-10-20 2011-04-12 Irwin Industrial Tool Company Spade bit
US20080101879A1 (en) * 2006-10-31 2008-05-01 Durfee Laverne R Spade-type bit
US20080202780A1 (en) * 2007-02-28 2008-08-28 Reiter John P Power Drill Accessory for Loosening Soil
CN104339423A (en) * 2014-10-24 2015-02-11 浙江博泰家具有限公司 Drilling machine for furniture board material
CN104339423B (en) * 2014-10-24 2016-01-20 浙江博泰家具有限公司 A kind of block machine of Furniture panel
CN106270662A (en) * 2015-06-03 2017-01-04 襄阳三鹏航空科技有限公司 Curved surface opens circular hole device
USD863384S1 (en) * 2018-04-30 2019-10-15 Disston Company Spade drill bit
CN110682391A (en) * 2019-09-12 2020-01-14 广东韶钢工程技术有限公司 Manufacturing method and application of cast lost foam wood drill bit
USD931917S1 (en) * 2020-04-18 2021-09-28 Danyang Linrui Tools Co., Ltd. Drill

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