US2551778A

US2551778A - Sweep cutter

Info

Publication number: US2551778A
Application number: US566837A
Authority: US
Inventors: Harry C Wilson
Original assignee: ROBERT H CLARK
Current assignee: ROBERT H CLARK
Priority date: 1944-12-06
Filing date: 1944-12-06
Publication date: 1951-05-08
Anticipated expiration: 1968-05-08

Description

Ma 8, 1951 H, c, ML ON 2,551,778

SWEEP CUTTER Filed Dec. 6, 1944 I fifezm C Mao/v Allan/72y Patented May 8, 1951 SWEEP CUTTER Harry G. Wilson, Beverly Hills, Califi, assignor to Robert H. Clark, Los Angeles, Calif.

Application December 6, 1944, Serial No. 566,837

Claims.

This invention has to do with a cutter and it is a general object of the invention to provide a cutter of the type commonly referred to as a fly cutter and in which the cutter proper, or blade, is mounted so that it will not bite into the material being worked upon and will not chatter during operation.

Adjustable cutters, known commonly as fly cutters, are used extensively for drilling or boring various materials and are characterized by a central body that is rotated, an arm projecting laterally from the body and a cutting blade carried by the arm to engage the work or material being out. With the usual construction found in such a device there is a marked tendency for the cutter or blade to bite into the work, this being particularly true when certain materials are being worked upon, and it is very common for the cutter or blade to chatter. As a result of the difliculties mentioned the usual fly cutter seldom works or operates smoothly or cuts a clean hole but, more generally, chatters during use and the hole made is seldom clean and smooth. It also often occurs that the cutting blade, if thin or delicate, is broken in the course of use of the ordinary fly cutter.

It is an object of this invention to provide a fly cutter characterized by a head which supports the cutter or blade so that it will cut effectively and smoothly and without chatter. The construction that I have provided is such as to support the cutting blade accurately and dependably and with slight resilience so that it clears itself from the work when excessive pressures develop rather than being rigidly held to be forced into the work.

Another object of my invention is to provide a fly cutter of the general character referred to in which the desired resiliency is obtained through the formation or design of the head provided for carrying the blade. In my construction the head is of simple, inexpensive formation and at the same time has a certain limited inherent resiliency which causes the blade to be supported in a most advantageous manner.

Another object of my invention is to provide a cutter of the general character referred to in which the head for carrying the cutter blade is in the form of a block formed integrally on the outer end of the adjustable arm, which block is given the desired characteristics through simple, easily performed machining operations.

The various objects and features of my invention will be fully understood from the following detailed description of typical preferred forms 2 and applications of the invention, throughoutwhich description reference is made to the accompanying drawings, in which:

Fig. 1 is a side elevation of a fiy cutter embodying the present invention taken to show the front or leading edge of the blade carried by the block provided on the end of the adjustable alllll. in Fig. 1, showing the side of the blade, being a view taken as indicated by line 2-2 on Fig. '1. Fig. 3 is a plan section taken as indicated by line 3-3 on Fig. 1. Fig. 4 is a view similar to Fig. 1 showing another form of construction embodying the invention. Fig. 5 is a view similar to Fig. 2 showing the form of construction illustrated in Fig. 4. Fig. 6 is an enlarged, detailed, sectional view taken as indicated by line 6-6 on Fig. 4, and Figs. 7 and 8 are enlarged sectional views of blades that can be used.

an Referring first to the form of the invention illustrated in Figs. 1 to 3, inclusive, the device embodying the invention involves, generally, a body it, an arm H to be carried by the body to project laterally therefrom, means l2 mounting the arm on the body, a block l3 on the outer end of the arm, a cutter or blade M to be carried by the block, and means I5 mounting the blade on the block.

The body I0 is preferably an elongate element adapted to be rotated about its longitudinal axis and in its preferred form it is provided at its upper end with a mounting shank 20. The particular body shown in the drawings is square in cross sectional configuration and the shank 20 is integral with the body and is a tapered shank commonly employed on tools of the character under consideration. In practice it is desirable to provide the tool with a pilot either in the form of a pin or drill. In the drawings I show the body provided with a central pilot opening- 2| and I show a drill 22 arranged in the opening to project downwardly beyond the lower end of the body and secured in position by a set screw 23.

The arm H is preferably a straight bar-like element and may, in practice, be substantially rectangular in cross sectional configuration and of considerable length to be adjustable so that its outer end, which carries the block I3, is removed a substantial distance from the body Ill.

The means l2 for mounting the arm on the body may vary widely in form and design, it being the primary purpose of such means to secure the arm to the body so that it projects laterally therefrom and is held rig-idly during operation of the tool.

Fig. 2 is a side elevation of the tool shown.

In the form illustrated I V provide a channel or notch-like opening 30 across one side face of the body and proportion the channel to slidably receive or carry the arm The means I2 includes, in addition to the channel or recess of the arm into the body. a clamp rin or washer 3| to engage or overlie the arm, and a clamp screw 32 threaded to the body and carrying the clamp washer. The screw 32 may be an ordinary cap screw carried in a tapped bore provided transversely in the body from the face that is provided with the channel and located adjacent the channel so the parts bear the relationship clearly illustrated in Figs. 1 and 2 of the drawings. When the screw 32 is made tight the clamp washer 3| bears tightly against the outer side of the arm H and thus clamps the arm tight in the channel 30.

Through the construction just described the arm can be readily set in various positions relative to the body or to bring the outer end thereof, which carries the block l3, into any desired position relative to the body so long as a substantial portion of the arm is carried in the channel or at least enough of the arm is carried in the channel to be engaged and clamped by the clamp washer 3 I.

The block provided by my invention on the outer end of the arm for carrying the blade |4 preferably includes a head 40 spaced from the arm H and a neck or shank 4| joining the head with the arm. In the preferred arrangement the head 40 is spaced immediately below the outer end portion of the arm I and the shank 4| which supports the head joins the arm and head and is shaped and proportioned to support the head with a limited degree of resiliency or yield.

In the preferred form of the invention the shank 4| is a curved element and projects forward and down from the outer end portion of the arm, as clearly shown in Fig. 2 of the drawings. In practice I form the upper end of the shank integral with the forward side of the arm H at the projecting end of the arm and the lower end of the shank joins the forward portion of the head 40. To give the shank 4| the desired shape or curvature I provide a gradually curved or convex forward or outer side 42 on the shank and a corresponding concave inner side thereon. To easily form the inner side in the desired manner I provide the block which forms the head and shank with a round opening or bore 45 and in the form of the invention under consideration I make this openin rather small in diameter and then provide a suitably curved kerf or cut 48 in the block, which cut establishes the concave side of the shank. In the particular form of the invention being described the cut 46 has a part 47 which separates the arm H from the head 40, as clearly shown in Fig. 2 of the drawings. From the foregoing description it will be apparent how the block can be easily manufactured from a solid body into the head 40 and curved supporting shank by simply drilling the hole 45 and forming the

kerf having parts

46 and 41.

In accordance with my invention the cutter or blade I4 is carried by one face 50 of the head 40. In the form of the invention under consideration the outermost or lateral end face of the head is employed to carry the blade and this face is provided with a vertical channel 5| which slidably holds the blade. When this construction is employed and when the end face 50 of the head is coincidental with the end face 55 of the arm H, as is shown in the drawings, the end face 55 of the arm is recessed at 56 to provide clearance for the upper end of the blade should it project above the head 40. I may also provide a cutter carrying channel 5| in the inner side face of the head so a blade can be carried at that point instead of or in addition to being carried at the outer side of the head.

The cutter or blade |4 may be a fiat, simple blade designed to cut a channel or groove in the material worked upon. When the blade is flat sided as shown in Fig. 7, it is preferably given a slight rearward taper for clearance. The blade may be curved as shown in Fig. 8, in which case it may also be tapered for clearance. In the drawings I have shown a very simple form of blade having its lower end dressed to form a cutting edge 60, it being understood that blades of various forms and designs may be employed, as circumstances may require.

The means |5 for securing the blade M to the head 40 preferably involves a simple clamp such as a clamp bolt. In the drawings I have shown a clamp bolt 6| carried by the head 40 and having a head 62 which overlaps and engages the cutter blade M to hold it in its mounting channel 5|. The bolt 6| extends through the head and at the side opposite the cutter carries a clamp nut 63.

With the construction that I have provided the arm II is adjusted so that the block |3 is supported at the desired point relative to the body |0 and a cutter blade of the desired form and shape is clamped to the head 40 to be rigidly carried thereby and to depend therefrom in a manner such as I have illustrated in the drawings. As the tool is operated in the manner common to fly cutters the blade |4 may be ad vanced into the work or material and as the tool rotates the blade will cut a groove or channel in the material. Under ordinary working conditions the structure that I have provided holds the blade rigidly or solidly. However, should there be any tendency for the blade to bite into the work and thus create excessive strains that might injure the blade or cause chattering the shank 4| affords relief or allows the head 49 to spring back slightly and enough to relieve the cutter. It will be understood that, in practice, the spring or yieldability of the shank can be Varied by varying its shape and proportioning and that various degrees of yield may be provided to meet varying working conditions.

In the form of the invention shown in Figs. 4, 5 and 6 of the drawings the general construction is substantially the same as that above described, except that the body It] instead of being shown square in cross section is round in cross section, and the block |3 at the outer end of the arm is slightly different in form from that above described, while the means I5 is also somewhat different in form.

The block |3 is essentially the same as the block |3 above described except that the bore 45 is considerably larger in diameter than the bore 45 and forms the major part of the curvature of the shank 42*. In this form of the invention as in the one first described, the head is separated from the arm by a cut provided in the block joining the bore 45 In this form of the invention there is a single, straight kerf or cut 4'! serving this purpose. The head M3 in this form of the invention projects slightly to the rear of the arm and the rear side 50 of the head is employed to support the cutter blade.

The means |5 in this form of the invention involves a clamp block 10 with flanges 1| embracing the head so the block is guided vertically on the rear face 50 of the head. One or more vertical channels 5W are provided in the block facing the head and a screw Sl joins the block to the head. When the screw 6| is tightened the clamp block ill is moved toward the head so that a cutter carried in one of the channels is clamped tight against the face 50 of the head. With the arrangement just described the cutter blade depends from the rear face of the head rather than from the side or end face thereof, and by providing channels 5| in the clamp block 10 more than one cutter can be carried at a time and the cutter can be mounted so that it is as close as possible to the body m To facilitate adjustment of the structure so that the blade is very close to the body 10* the body I0 is notched out at 80, as shown in Fig. 4.

The operation of the form of the invention shown in Figs. 4 to 6, inclusive, is substantally the same as that hereinabove described, that is, the arm can be adjusted to any desired position and the cutter depending from the head ll! is mounted so that it is solid or firm for all practical purposes but because of the curved shank 42* can spring or yield rearwardly to relieve excessive strain.

Having described only typical preferred forms and applications of my invention, I do not wish to be limited or restricted to the specific details 7:

herein set forth, but wish to reserve to myself any variations 0r modifications that may appear to those skilled in the art and fall within the scope of the following claims:

Having described my invention, I claim:

1. A cutter of the character described inc1uding a body with a mounting stem, an arm carried by the body to project laterally therefrom, a cutter, a block fixed on the outer end of the arm to support the cutter and including a head spaced from the arm and having a rear cutter supporting face and a forwardly projecting curved shank fixed to the forward sides of the head and arm and having flexibility in the plane of cut to yield slightly under excessive strain applied to the cutter, and means holding the cutter on said supporting face.

2. A cutter of the character described including a body with a mounting stem, an arm carried by the body to project laterally therefrom, a cutter, a unitary block on the arm to support the cutter and including a head spaced immediately below the outer end portion of the arm and having a fiat rear cutter supporting face rearward of the arm, the block including a curved shank fiexible relative to the head and arm and integrally joining the head to the arm and supporting the head to yield rearwardly under excessive strain applied to the cutter, the shank extending forward and downward from the front side face of I the arm substantially parallel with the direction of cut and then downwardly and rearward to join the forward portion of the head, and clamp means holding the cutter on said cutter supporting face.

3. A cutter 'of the character described including a body with a mounting stem, an arm carried by the body to project laterally therefrom, a cutter, a block on the outer end of the arm having a head with a rear face and a curved shank resiliently connecting the head and arm, and means mounting the cutter on the rear face of the block including a clamp block carrying the cutter and a screw connecting the clamp block to the head so the cutter is clamped to the head, the clamp block and head having cooperating parts holding the clamp block against turning relative, to the head.

4. A cutter of the character described including a body with a mounting stem, an arm carried by the body to project laterally therefrom, a cutter, a block on the outer end of the arm having a head with a rear face and a curved resilient shank joining the head and the arm, and means mounting the cutter on the rear face of the block including a clamp block opposite the said rear face and having cutter carrying channels opposing said face and a screw connecting the clamp block to the head so a cutter in a chan nel is clamped to said face of the head.

5. A cutter of the character described including a body with a mounting stem, a pilot carried by the body concentric with the stem, an arm carried by the body to project laterally therefrom, a cutter, a block on the outer end of the arm having a head with a rear face and a curved resilient shank joining the head and arm, and means mounting the cutter on the said rear face of the head including a clamp with cutter carrying channels opposing the said face and a screw connecting the clamp to the head so a cutter in a channel is clamped to said face of the head, the body having a recess extending to a point adjacent the pilot for reception of the block.

HARRY C. WILSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 63,882 Gruger Apr. 16, 1867 286,610 Heysinger Oct. 16, 1883 1,237,021 Corke Aug. 14, 1917 1,323,570 Basmaison Dec. 2, 1919 1,382,447 Wells June 21, 1921 1,746,463 Elder Feb. 11, 1930 2,083,418 Andrews June 8, 1937 2,225,224 Landrum Dec. 17, 1940 2,269,510 Bates Jan. 13, 1942