Multiple stop for power tools

Claim 2

A multiple-stop apparatus for automatic control of the depth of cut in a workpiece, attachable to the movable cutting tool carriage of a power tool, having stationary parts including a bearing surface thereon, comprising: a shaft attachable to the cutting tool carriage parallel to the travel thereof; a rotatable collar on the shaft; means for restricting longitudinal movement of the collar on the shaft; a plurality of stops fastened to the collar and adjustable thereto in the direction of travel of the cutting tool carriage, the shaft being positioned relative to the stationary bearing surface of the power tool so that any of the stops may be selectively placed in alignment with the bearing surface by rotating the collar, so that abutment of the selected stop against the bearing surface restricts further movement of the carriage; pointer means; and a scale adjacent the pointer means and parallel to the travel of the carriage relative to a stationary part, the pointer means being fixed to one of these members and the scale being fixed to the other, whereby travel of the carriage relative to the stationary part may be measured.

Claim 3

The apparatus of claim 1 further including a spring-loaded, ball catch fastened to the collar radially so that the ball thereof is urged inwardly toward the shaft, which has indentations into which the ball may be partially forced, to provide rotational stop means for the collar on the shaft, the number and spacing of the indentations relative to the ball catch and the adjustable stops being such as to bring any selected stop into alignment with the stationary bearing Surface on the power tool, whereby such selective alignment may be quickly and accurately achieved.

Claim 4

The apparatus of claim 1 wherein the stops in the collar are screws engaged in threaded holes circumferentially spaced in the collar.

Claim 5

The apparatus of claim 1 wherein at least one stop is a rod, noncircular in cross section, that fits slidably into a hole of the same noncircular shape in the collar; and further includes serrations on one side of the rod; and an elongated slide member, having a wedge-shaped edge, slidably engaged in a slot extending into the collar from the edge thereof adjacent the serrations of the rod, whereby the stop may be adjusted incrementally by wedging the slide member between selected serrations thereon.

Claim 6

The apparatus of claim 4 wherein the stop has an enlarged head at the top end thereof, so that it cannot fall through its hole in the collar when the slide member is withdrawn, and wherein the stop has a scale imprinted thereon for measuring its against the stop, relative to the stop may surface of the over a collar.

Claim 7

The apparatus of claim 1 wherein at least one stop is a rod, slidably engaged in a hole in the collar; and further includes a set screw, radially oriented and threadedly engaged in the collar from the edge thereof so that it may bear against the stop, whereby the stop may be quickly adjusted over a wide range of hole depths.

Claim 8

The apparatus of claim 4 wherein the stop has an enlarged head at the top end thereof, so that it cannot fall through its hole in the collar when the set screw is loosened, and wherein the stop has a scale imprinted thereon for measuring its adjustment relative to the upper surface of the stop collar.

Claim 9

The apparatus of claim 1 wherein at least one of the stops is a rack gear slidably engaged in a hole in the collar; and further includes a pinion gear radially oriented in the collar in mesh with the rack gear; and a handle centrally attached to the pinion gear and extending beyond the edge of the collar for rotating the pinion gear and adjusting the stop.

Claim 10

The apparatus of claim 1 including an arm slidably engaged on the shaft in keyed relationship therewith between the collar and the stationary bearing surface on the power tool and extending outwardly from the shaft and shaped to be always in alignment with the stationary bearing surface and a limit switch on the power tool, whereby both a mechanical stop and a power shutoff may be achieved.

Claim 11

The apparatus of claim 1 including: a second collar on the shaft; means for preventing longitudinal and rotational movement of the second collar on the shaft; and a plunger-type micrometer fixed to the collar, the plunger being oriented to contact any one of the stops selectively as the stop collar is rotated on the shaft, whereby adjustment of the selected stop may be accurately measured.

Claim 12

The apparatus of claim 1 further including a rod having threads on one end, the threaded portion being of smaller diameter than the remainder of the rod to form a shoulder; a yoke having two holes therein to fasten the shaft and rod together in parallel relationship, the shaft also being threaded on one end similarly to the rod, and nuts to confine the yoke against said shoulders, and whereby a portion of the movable carriage of the power tool may be confined between the yoke and one of said shoulders; and an actuator having the form of a body with a hole through which the rod extends, so that the actuator may slide freely thereon, the upper surface of the actuator being a precision bearing surface on which the selected stop may bear, and the under surface being an actuating surface for operating a limit switch and for contacting the stationary portion of the drill press as the actuator is moved on the rod by the selected stop.

Claim 13

A multiple stop apparatus attachable to a drill press having a stationary portion and a movable carriage that holds a cutting tool, comprising: a U-shaped member formed by a shaft, a Rod, and a yoke joining them together; attachment means for fastening the U-shaped member to the movable carriage of the drill press parallel to the travel thereof; a sleeve on the shaft, having circumferentially-spaced indentations therein; adjustment means for adjusting the longitudinal position of the sleeve on the shaft and fixing it in a desired position; a stop collar rotatably positioned on the sleeve and having circumferentially spaced holes therein; means for restricting the longitudinal position of the collar on the sleeve; a spring-loaded ball catch radially oriented in the stop collar so that the ball thereof may be partially forced into a selected one of the indentations in the sleeve, as the collar is rotated; a plurality of stops adjustably engaged in the holes in the collar in a direction parallel to the shaft; and a sliding actuator having the form of a body with a hole therethrough on the rod between the stop collar and the stationary portion of the drill press, portions of the actuator being simultaneously alignable with a selected stop and with said stationary portion, whereby a positive mechanical restraint will result as the stop approaches the stationary portion, to regulate the cutting depth in a work piece.

Claim 14

A multiple stop apparatus attachable to a drill press having a stationary portion and a movable carriage that holds a cutting tool, comprising: a U-shaped member formed by a shaft, a Rod, and a yoke joining them together; attachment means for fastening the U-shaped member to the movable carriage of the drill press parallel to the travel thereof; a sleeve on the shaft, having circumferentially-spaced indentations therein; adjustment means for adjusting the longitudinal position of the sleeve on the shaft and fixing it in a desired position; a stop collar rotatably positioned on the sleeve and having circumferentially spaced holes therein; means for restricting the longitudinal position of the collar on the sleeve; a spring-loaded ball catch radially oriented in the stop collar so that the ball thereof may be partially forced into a selected one of the indentations in the sleeve, as the collar is rotated; a plurality of stops adjustably engaged in the holes in the collar in a direction parallel to the shaft; and a sliding actuator having the form of a body with a hole therethrough on the rod between the stop collar and the stationary portion of the drill press, portions of the actuator being simultaneously alignable with a selected stop and with said stationary portion, whereby a positive mechanical restraint will result as the stop approaches the stationary portion, to regulate the cutting depth in a work piece.

Claim 15

The multiple stop apparatus of claim 12 wherein at least one of the adjustable stops in the stop collar has external screw threads and the hole in the collar in which it is engaged is also threaded, for positive engagement and adjustment of the stop therein.

Claim 16

In a drill press having a stationary portion and a movable carriage holding a drill bit, the improvement comprising: a yoke fixed to the movable carriage and formed as a projection thereon; a shaft fixed to the yoke and oriented parallel to the motion of the carriage; a rod fixed to the yoke parallel to the shaft; a rotatable stop collar on the shaft; means for adjustably fixing the longitudinal position of the stop collar on the shaft; a plurality of stops carried by the collar and adjustable thereto parallel to the motion of the carriage; a sliding actuator on the rod, and having a bearing surface and an actuating surface thereon, the shaft and collar being positioned relative to the bearing surface of the actuator so that any one of the stops may be rotated into alignment therewith, and the actuator being in alignment with the stationary portion of the drill press, whereby depth of the drill bit in a work piece may be automatically determined.

Claim 17

In a drill press having a stationary portion and a movable carriage holding a drill bit, the improvement comprising: a yoke fixed to the movable carriage and formed as a projection thereon; a shaft fixed to the yoke and oriented parallel to the motion of the carriage; a rod fixed to the yoke parallel to the shaft; a rotatable stop collar on the shaft; means for adjustably fixing the longitudinal position of the stop collar on the shaft; a plurality of stops carried by the collar and adjustable thereto parallel to the motion of the carriage; a sliding actuator on the rod, and having a bearing surface and an actuating surface thereon, the shaft and collar being positioned relative to the bearing surface of the actuator so that any one of the stops may be rotated into alignment therewith, and the actuator being in alignment with the stationary portion of the drill press, whereby depth of the drill bit in a work piece may be automatically determined.

Claim 18

The drill press of claim 14 further including: an electric limit switch on the stationary portion thereof, and in alignment with the bearing surface of the sliding actuator, whereby electric power may be turned off when appropriate depth of cut has been achieved; a scale on a stationary part of the drill press, arranged parallel to motion of the carriage; and a pointer on the shaft arranged to indicate positions on the scale.