Patent EP0132652A2 successfully refreshed from Google Patents.
EP0132652A2
Expired / Lapsed
EP
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Method of manufacturing a printed circuit board drill
Assignee: Precorp Inc
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Filing: 1984-07-05
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Granted: —
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Expires: 2004-07-05
Abstract
Abstract An abrasive tipped drill of .006 to .125 inch diameter is provided for drilling holes in printed circuit boards. A composite sintered abrasive tip of cemented carbide and diamond or cubic boron nitride is formed such that the carbide can be ground away to expose the abrasive as the cutting surfaces of the drill. A shank of tough material having high transverse rupture strength is provided with a reduced section which forms the body of the drill. The tip is secured to the reduced section and flutes are ground overthe combined length ofthe tip and reduced section.
Inventors
- 👤 John Alan Bunting
- 👤 James Larsen Clark
- 👤 Louis Mcconkie Pope
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 16:45
CPC Classifications
B; B23; B23B; B23B51/00; B23B51/02; B22; B22F; B22F7/00; B22F7/06; B23B51/0002; B23P; B23P15/00; B23P15/28; B23P15/32; B22F5/00; B22F2005/001; B23B2240/00; B23B2240/08; B23B2251/00; B23B2251/18; B23B2251/50; B23B51/011; H; H05; H05K; H05K3/00; H05K3/0011; H05K3/0044; H05K3/0047
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
56 words
A composite sintered abrasive tip for use in a printed circuit board drill, including a generally cylindrical blank of cemented carbide having a flat surface at one end and a vein of sintered abrasive particles imbedded within a groove in the opposite end, said abrasive particles being bonded to each other and to the cemented carbide.
Claim 2
Dependent Claim
56 words
A composite sintered abrasive tip for use in a printed circuit board drill, including a generally cylindrical blank of cemented carbide having a flat surface at one end and a vein of sintered abrasive particles imbedded within a groove in the opposite end, said abrasive particles being bonded to each other and to the cemented carbide.
Claim 3
Dependent Claim
31 words
A composite sintered abrasive tip as defined in Claim 1 in which the vein of sintered abrasive particles is exposed at the opposite end and along opposite sides of the blank.
Claim 4
Dependent Claim
32 words
A composite sintered abrasive tip as defined in Claim 2 in which the vein has the general configuration of a rectangular prism with one wedge-shaped arcuate segment extending laterally from each side.
Claim 5
Dependent Claim
23 words
A composite sintered abrasive tip as defined in Claim 3 wherein the blank is tough cemented carbide and the abrasive particles are diamond.
Claim 6
Dependent Claim
25 words
A composite sintered abrasive tip as defined in Claim 3 wherein the blank is tough cemented carbide and the abrasive particles are cubic boron nitride.
Claim 7
Dependent Claim
31 words
A composite sintered abrasive tip as defined in Claim 2 in which the vein is relatively shallow and extends across the end of the tip and down the opposed sides thereof.
Claim 8
Dependent Claim
31 words
A composite sintered abrasive tip as defined in Claim 2 in which the vein is discontinuous and includes two segments, each segment extending radially inward from the circumference of the tip.
Claim 9
Dependent Claim
48 words
A printed circuit board drill comprising an elongated shank of suitable tough material a composite sintered abrasive tip secured to one end of the shank, said tip including a blank of cemented carbide with a vein of sinterd abrasive particles imbedded within a groove removed from the shank.
Claim 10
Dependent Claim
48 words
A printed circuit board drill comprising an elongated shank of suitable tough material a composite sintered abrasive tip secured to one end of the shank, said tip including a blank of cemented carbide with a vein of sinterd abrasive particles imbedded within a groove removed from the shank.
Claim 11
Dependent Claim
25 words
A printed circuit board drill as defined in Claim 8 in which the blank is cylindrical and the vein extends transversely across one end thereof.
Claim 12
Dependent Claim
29 words
A printed circuit board drill as defined in Claim 9 in which the vein of abrasive particles is exposed at one end and along opposed sides of the blank.
Claim 13
Dependent Claim
30 words
A printed circuit board drill as defined in Claim 10 in which the shank is provided with a reduced section extending from one end, and the tip is secured thereto.
Claim 14
Dependent Claim
32 words
A printed circuit board drill as defined in Claim 11 in which helical flutes extend from one end of the tip over the combined length of the tip and the reduced section.
Claim 15
Dependent Claim
48 words
A printed circuit board drill as defined in Claim 12 in which the vein of abrasive particles has the general configuration of a rectangular prism with one wedge-shaped arcuate segment extending laterally from each side, the exposed segments forming the web and the cutting tip of the drill.
Claim 16
Dependent Claim
28 words
A printed circuit board drill as defined in Claim 13 in which the edges at the segments opposed to the prism form the cutting lips of the drill.
Claim 17
Dependent Claim
26 words
A printed circuit board drill as defined in Claim 14 in which the blank is formed of tough cemented carbide and the abrasive particles are diamond.
Claim 18
Dependent Claim
27 words
A printed circuit board drill as defined in Claim 14 in which the blank is formed of tough cemented carbide and the abrasive is cubic boron nitride.
Claim 19
Dependent Claim
62 words
A process of manufacturing a composite sintered abrasive tip for a printed circuit board drill which comprises providing a generally cylindrical blank of cemented carbide providing a transverse groove in one end of the blank, filling the groove with a mixture of abrasive particles, and sintering the blank and abrasive mixture to bond the particles to each other and to the carbide.
Claim 20
Dependent Claim
62 words
A process of manufacturing a composite sintered abrasive tip for a printed circuit board drill which comprises providing a generally cylindrical blank of cemented carbide providing a transverse groove in one end of the blank, filling the groove with a mixture of abrasive particles, and sintering the blank and abrasive mixture to bond the particles to each other and to the carbide.
Claim 21
Dependent Claim
44 words
A process of manufacturing a composite sintered abrasive tip for a printed circuit board drill as defined in Claim 17 which comprises forming the transverse goove with the general configuration of a rectangular prism with one wedge-shaped arcuate segment extending laterally from each side.
Claim 22
Dependent Claim
92 words
A process of manufacturing a composite sintered abrasive tip for a printed circuit board drill as defined in Claim 17 which comprises mixing the abrasive particles with a fugitive binder, packing the abrasive mixture into the groove covering the mixture with a disc of catalytic material, placing the blank and abrasive in a mold of cemented carbide, loading the mold into a HP/HT press, and sintering the contents of the mold at a pressure of 45Kbar to 75Kbar and temperatue of 1200°C to 1600°C for a period of 1 to 20 minutes.
Claim 23
Dependent Claim
83 words
A process of manufacturing a printed circuit board drill which comprises providing a generally cylindrical cemented carbide blank with a transverse groove in one end, filling the groove with a mixture of abrasive particles sintering the blank and abrasive mixture in a HP/HT press to bond the particles to each other and to the carbide, securing the blank to one end of a shank, and grinding the carbide to expose a portion of the abrasive to provide the cutting surfaces of the drill.
Claim 24
Dependent Claim
83 words
A process of manufacturing a printed circuit board drill which comprises providing a generally cylindrical cemented carbide blank with a transverse groove in one end, filling the groove with a mixture of abrasive particles sintering the blank and abrasive mixture in a HP/HT press to bond the particles to each other and to the carbide, securing the blank to one end of a shank, and grinding the carbide to expose a portion of the abrasive to provide the cutting surfaces of the drill.
Claim 25
Dependent Claim
37 words
A process of manufacturing a printed circuit board drill as defined in Claim 20 which comprises forming the groove normal to the longitudinal axis of the blank and across at least the outer portions of its width.
Claim 26
Dependent Claim
30 words
A process as defined in Claim 21 which includes forming the groove to the general configuration of a rectangular prism with one wedge-shaped arcuate segment extending laterally from each side.
Claim 27
Dependent Claim
45 words
A process as defined in Claim 20 which includes providing the shank with a reduced section at one end, securing the blank to the free end of the reduced section, and grinding helical flutes over the combined length of the blank and the reduced section.
References Cited (Backward Citations)
No citation records indexed.
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