Constant depth cutter assembly

Claim 1

In an apparatus for use with a cutter for controlling the depth of cuts made in a workpiece, said apparatus being of the type comprising first means for contacting the surface of the workpiece, said first means including a planar portion the plane of which contains a point positioned so as to lie on an axis of the cutter whereby the cutter will project beyond said point a predetermined distance; and second means upon which said first means is mounted, said second means being operative to enable said first means to be freely universally pivoted about said point, the improvement comprising bearing means disposed vertically above said first and second means for maintaining said point substantially on the surface of the workpiece, said bearing means comprising a motor housing containing a motor for driving the cutter, and an annular bearing member in which said motor housing is vertically slidably mounted, said first and second means being secured to said motor housing for instantaneous vertically reciprocating movement concurrent with similar movement of said motor housing, an upward component of said vertically reciprocating movement being in response to a vertical force exerted upon said planar portion by vertically rising portions of the surface of the workpiece encountered by said planar portion, and said bearing means further providing instantaneous lowering of said planar portion in response to contact between said planar portion and vertically declining portions of the surface of the workpiece.

Claim 9

An apparatus for making controlled depth cuts on a surface of a workpiece, said apparatus comprising: a. a rotary cutter having a vertically disposed axis of rotation; b. a motor for rotatably driving said cutter, said motor being contained in a cylindrical housing; c. an annular bearing member in which said motor housing is mounted for vertical reciprocating movement; d. a manifold member connected to said motor housing for vertical reciprocating movement concurrently therewith, said manifold member including a convex socket; and e. a workpiece-contacting member mounted on said manifold member and including a spherically convex surface extending into said socket for freely pivotal movement therein, said workpiece-contacting member including a planar portion disposed on the surface of the workpiece, and an opening through said planar portion, said cutter extending through said opening and having its axis of rotation coaxial with the center of said opening, said workpiece-contacting member being operable to instantaneously impart vertical movement to said motor housing and manifold member in response to contour changes on the surface of the workpiece to maintain contact between said planar portion and the surface of the workpiece being cut.

Claim 10

An apparatus for making controlled depth cuts on a surface of a workpiece, said apparatus comprising: a. a rotary cutter having a vertically disposed axis of rotation; b. a motor for rotatably driving said cutter, said motor being contained in a cylindrical housing; c. an annular bearing member in which said motor housing is mounted for vertical reciprocating movement; d. a manifold member connected to said motor housing for vertical reciprocating movement concurrently therewith, said manifold member including a convex socket; and e. a workpiece-contacting member mounted on said manifold member and including a spherically convex surface extending into said socket for freely pivotal movement therein, said workpiece-contacting member including a planar portion disposed on the surface of the workpiece, and an opening through said planar portion, said cutter extending through said opening and having its axis of rotation coaxial with the center of said opening, said workpiece-contacting member being operable to instantaneously impart vertical movement to said motor housing and manifold member in response to contour changes on the surface of the workpiece to maintain contact between said planar portion and the surface of the workpiece being cut.