US2263870A

US2263870A - Keyway cutting tool

Info

Publication number: US2263870A
Application number: US339332A
Authority: US
Inventors: Currie Dugald
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-06-07
Filing date: 1940-06-07
Publication date: 1941-11-25
Anticipated expiration: 1958-11-25

Description

Nov. 2 5 194.1. D. CURRIE KEYWAY CUTTING TOOL Filed June 7, 1940 mi w Patented Nov. 25, 1941 entree sraras raftercarrier E WAY cur ew 790.

Dug ald Currie DesMoine s Iowa. Application J iled, 1940,; Serial i t,- 339,332 3 Claims. (01. 90-40) The object of my invention is to provide a hand-operated keyway cutting tool for cutting keyways in round shafts at the ends thereof, which tool is of simple, durable and inexpensive construction.

- More specifically, it is my object to provide a tool of this class in which shafts of different diameters may be readily, quickly and easily clamped and firmly held with the longitudinal axes of the'shaft exactlyin line with the path of travel of the cutting tool, whereby the keyway formed by the tool will be exactly parallel with the longitudinal axis of the shaft, and further to provide a tool of this class in Which the manual power applied in the operation of the tool will necessarily be applied insuch manner as to form the side walls of the keyway exactly parallel to thelongitudinal axis of the shaft being cut, to thereby avoid distortion of said side 'walls as is commonly done with keywaycutters' now in commen use, in which the manual powerapplied for operating the tool is frequently applied in such manner as to laterally deflect the cutting tool during its cutting stroke and thereby forming side walls of the keyway along lines divergent from true parallelism with the longitudinalaxis of'the shaft.

In the accompanying drawing- Figure 1 shows a side elevation of my improved keyway cutter applied to a shaft, parts being '3' broken away to show certain structural details;

Figure 2 shows a vertical sectional view on the line 22 of Figure 1;

Figure 3 shows an end elevation looking toward the end at which the cutting tool is located;

Figure 4 shows a horizontal sectional view on the line 4-4 of Figure 1;

Figure 5 shows a detail perspective view of the cutter blade and a part. of the blade holder in which the blade is slidingly mounted; and

Figure 6 shows a detail sectional view on the line 6-6 of Figure 1.

The reference numeral It indicates the body portion of the tool which serves as a support for the entire tool. a centrally arranged longitudinal opening I I at its lower portion, of a size to freely receive the largest shafts for which the tool is adapted; the upper wall forming this opening has its sides tapered inwardly and upwardly at I2 along lines parallel with the longitudinal axis of the body. Set screws I3 are extended through the lower portion of the body It into the opening It to engage the under central portion of a shaft in the This y portion is formed with opening. When these set screws are forced firmly 55 the body It.-

against a shaft I4 the shaft is thereby forced against the tapered walls l2 and thereby moved to position exactly parallel with the longitudinal axis of the body, and there firmly held.

Directly above the opening II is a'longitudinal opening I5 centered relative to the shaft opening and of rectangular formation. Slidingly mounted within the opening is the cuttingtool supporting bar It, capable of longitudinal movement only and so ac'curat'elyfitted as to prevent lateral movement. At one end of the bar I fi'is ah integral upward extension IT.

The "tool-carrying frame comprises two side members I8 overlapping the sideof the extension I I and pivotally connected therewith by the pivot pin IBat its top portion. The body portion I9 of this frame is extended across the front of the extension I], and is forme'd'with a tapered groove at its front central portion, in line longitu-' dinally with the longitudinal center of the bar I6. In this groove 20 there is slidingly mounted a tool holder 2| tapered to fitthe groove and having an'opening to receive the cutting tool 22. The side edgesof the tool and holder are tapered to prevent forward'movement of the tool relativeto theholdei." A tool guiding plate 23 is secured to the front of the body portion I9 by bolts 24. At the upper end of the plate 23 is a rearward extension 25 in which is mounted a feed screw 26 to engage the upper end of the tool 22. A winged set screw 21 is mounted in the central portion of the body I 9 for clamping the tool in various positions of its adjustment.

At the rear end of the bar I 6 there is a rectangular extension 28, of reduced size, extended through an upright 29 which has a rectangular opening accurately fitting the extension. This upright is fixed to the bar I6 by a nut 30 on the rear of the extension.

Fulcrumed to the body Iil is a lever 3I accurately centered vertically above the longitudinal center of the shaft opening and movable forwardly and rearwardly. A link 32 connects the lever 3| with the upright 29.

Resting on top of the bar ing in the body set screws 32 I6 within the open- IE are two bearing plates BI, and

are extended through the top of to engage said bearing plates. In practice, I adjust said screws 32 to firmly engage the bar It, but not firmly enough to prevent longitudinal movement of the bar I6, thereby avoiding a chattering action which would occur if the bars It were permitted to move up and down in the body I I3.

In practical use a shaft of any desired diameter is placed in the opening II, and the set screws l3 are drawn up to firmly press the shaft against the tapered upper walls of the opening. This operation will automatically center the shaft and firmly hold it against both longitudinal and lateral movement. It is not necessary for the operator to exercise any skill in operating these set screws because they cannot function in any way to avoid the desired accurate centering of the shaft. Then a keyway cutting tool of the proper size for cutting the desired keyway is applied and firmly clamped, and then all that the operator need do is to reciprocate the lever 3|. Due to the fact that the tool-carrying guide bar is close to and parallel with the shaft being operated on, the cutter tool will not chatter-during the cutting stroke as is sometimes the case when the tool-carrying bar is widely spaced apart from the shaft, and due to the fact that the operating lever is centered directly above the longitudinal center of the shaft being operated on and movable only in a direction parallel with the shaft, all motion applied to the lever operates to move the'cutter tool in a straight line, hence, all lateral distortion of the keyway is avoided.

I claim as my invention:

1. A keyway cutting tool, comprising a body portion formed with two longitudinal openings, one being close to and directly above the other with their longitudinal centers in vertical alignment, the upper wall of the body at the lower opening being inclined from its side edges upwardly and inwardly, and the upper opening being rectangular in outline, set screws extended through the bottom of the body to engage a shaft in the lower opening and force it to centered position against said inclined wall, a tool-carrying bar in said upper opening, rectangular in section and slidingly mounted thereon, a cutting tool pivoted to one end of said bar in line vertically with the longitudinal center of the said lower opening, an upright fixed to the other end of said bar, a link pivoted thereto, a lever fulcrumed to the upper part of said body in line vertically with the longitudinal centers of said openings and pivoted to said link and movable longitudinally of said bar.

2. A keyway cutting tool, comprising a body portion formed with two longitudinal openings, one being close to and directly above the other with their longitudinal centers in vertical alignment, the upper wall of the body at the lower opening being inclined from its side edges upwardly and inwardly, and the upper opening being rectangular in outline, set screws extended through the bottom of the body to engage a shaft in the lower opening and force it to centered position against said inclined wall, a tool-carrying bar in said upper opening, rectangular in section and slidingly mounted thereon, an upright fixed to one end of the bar, a tool-carrying member pivoted thereto above the longitudinal center of the bar, a keyway cutter tool adjustably fixed to said tool-carrying member, an upright fixed to the other end of said bar, a link pivoted thereto, a lever fulcrumed to the upper part of said body in line vertically with the longitudinal centers of said openings and pivoted to said link and movable longitudinally of said bar.

3. A keyway cutting tool, comprising a rigid body portion formed with a longitudinally arranged opening to receive a shaft, the wall of said opening at the top being inclined inwardly and upwardly toward a longitudinal central line, means carried by the body portion for engaging a shaft in said opening and for forcing it upwardly against said inclined wall and thereby moving it to longitudinally centered position and fixing it in said position, said rigid body having a second longitudinal opening above the first, a tool-carrying bar slidingly mounted in the sec ond opening and centered above the center of the shaft opening, the tool carrying bar and its opening being of irregular outline and closely fitted to thereby prevent rotary movement of the tool-carrying bar, a lever fulcrumed to the body in line vertically with the longitudinal centers of the said openings, and a link pivoted to the lever and to the tool-carrying bar.

DUGALD CURRIE.