Hole cutting tools
First Claim
1. Cutting tool of generally cylindrical configuration rotatable about a central axis and defined by coaxial inner and outer surfaces and an axially forward portion defining a saw tooth cutting edge disposed generally between said surfaces and comprising a plurality of repetitive groups of teeth, each group including at least four set saw teeth having cutting edges radially displaced inwardly and outwardly of said inner and outer surfaces, said teeth being disposed successively in the direction of rotation of the tool with the cutting edge of each tooth of the group being disposed generally in a surface of rotation separate and distinct from the surfaces of rotation of the other cutting edges of the teeth in said group and said teeth being variably set radially so that the cutting edge of each tooth of said group includes an effective portion unmasked by any portion of said teeth rotatable in advance of said each tooth whereby when moving relative to the work at a given rotational speed and urged into the work at a given pressure, each tooth cuts a chip of generally the same thickness and width as each of the other teeth of said group.
2 Assignments
0 Petitions
Accused Products
Abstract
An improved hole saw for cutting holes having a cylindrical shape that includes, along its cutting edge, a plurality of repetitive groups of saw teeth having at least four radially displaced trailing teeth. The displacement of each trailing tooth is such that it has a substantially greater displacement than for any other tooth of said group preceding said trailing tooth. The displacement of each tooth being such that the cutting edge thereof is characterized as being movable along a cutting path different from the cutting paths of the other teeth of the group as the hole saw is rotated whereby each tooth cuts chips of uniform size. Each group of teeth may include a raker tooth having no substantial displacement with respect to the side surfaces of the hole saw. The raker tooth may be the same height or of greater height than the trailing teeth.
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Citations
12 Claims
- 1. Cutting tool of generally cylindrical configuration rotatable about a central axis and defined by coaxial inner and outer surfaces and an axially forward portion defining a saw tooth cutting edge disposed generally between said surfaces and comprising a plurality of repetitive groups of teeth, each group including at least four set saw teeth having cutting edges radially displaced inwardly and outwardly of said inner and outer surfaces, said teeth being disposed successively in the direction of rotation of the tool with the cutting edge of each tooth of the group being disposed generally in a surface of rotation separate and distinct from the surfaces of rotation of the other cutting edges of the teeth in said group and said teeth being variably set radially so that the cutting edge of each tooth of said group includes an effective portion unmasked by any portion of said teeth rotatable in advance of said each tooth whereby when moving relative to the work at a given rotational speed and urged into the work at a given pressure, each tooth cuts a chip of generally the same thickness and width as each of the other teeth of said group.
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12. Cutting tool of generally cylindrical configuration rotatable about a central axis and defined by coaxial inner and outer surfaces and an outer edge portion defining a saw tooth cutting edge disposed generally between said surfaces and comprising a plurality of repetitive groups of teeth, each group including a raker tooth and at least four set trailing teeth, at least two of said trailing teeth being radially displaced on opposite sides of the inner and outer surfaces of said cutting tool, the first of the trailing teeth being approximately the same height as the raker tooth before being displaced and at least two additional trailing teeth which are each shorter in length and having greater radial displacement than the first of the trailing teeth, the displacement of the first trailing teeth being approximately 50% of the displacement of the second trailing teeth, said teeth being disposed successively in the direction of rotation of the tool with the cutting edge of each tooth of the group being disposed generally in a surface of rotation separate and distinct from the surfaces of rotation of the other cutting edges of the teeth in said group and said teeth being variably set radially so that the cutting edge of each tooth of said group includes an effective portion unmasked by any portion of said teeth rotatable in advance of said each tooth whereby when moving relative to the work at a given rotational speed and urged into the work at a given pressure, each tooth cuts a chip of generally the same thickness and width as each of the other teeth of said group.
Specification