US2533665A

US2533665A - Pilot turning attachment for lathes

Info

Publication number: US2533665A
Application number: US626532A
Authority: US
Inventors: Bois Donald Du; Wheeler Percy
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-11-03
Filing date: 1945-11-03
Publication date: 1950-12-12
Anticipated expiration: 1967-12-12

Description

flona/z/ $11501 ercy wee/en Dec. 12, 1950 D. DU BOIS ET AL PILOT TURNING ATTACHMENT FOR LATHES Filed Nov. 5, 1945 Patented Dec. 12, 1950 UNITED STATES PATENT OFFICE 1 1L052 TURNING ATTACHMENT FOR LATH'ES Donald Du Bois, Ashokan, and Percy Wheeler, Poughkeepsie, Y.

Application November 3, 1945, Serial No. 626,532

2 Claims. 1

This invention relates to lathe attachments and accessories and has more specific reference to a comparatively small and simple device which we have chosen to identify as a pilot turning attachment, the same having been expressly designed as an improvement over the now customarily used or conventional two-roller type t-urners. Attachments of the aforementioned types are employed and used on lathes for stabilizing small sized stock rangn from one-sixteenth to threeeighths of an inch in diameter and are employed to overcome the tendency of stock to flex and spring away from the cutting end of the tool bit. Unless the .free end of the stock, adjacent the cutting tip of the tool is in some manner supported and held against fluttering and whipping, it is d fficult. if not almost impossible, to cause the tool to take a proper cut on the stock or work. In accordance with the principles of the instant invention, we contemplate the provision of a simple and expedient attachment which is applicable to the regularly used adjustable tool, said attachment being provided with a work piloting and retaining bearing, whereby the work is saddled, as it were, on the tool in order to maintain the proper relationship of parts for effective turning and cutting results.

Briefly, and in carrying out our invention, we contemplate the provision of a simple and feasible attachment characterized by two principal parts, a body which clamps adjustably on and is supported by the regular tool bit and a plate carried by said body and adjustable on the body, said plate being aper-tured and having roller bearing means fitted in said aperture, said roller bearing means serving to embrace and stabilize the free flexible end of stock or work, whereby it becomes possible to bring the cutting end of the tool bit and work into steadied relationshp during the period of the turning and cutting steps.

Other objects, features and advantages will become more readily apparent from the following description and the accompanying illustrative drawings.

In the drawings, wherein like numerals are employed to designate like parts throughout the views:

Figure 1 is a top plan view il ustrating fragmentary portions of a conventional lathe, showing the stock or work in the collet, the tool on the I post, the attachment on the tool; all parts set for useful operation.

Figure 2 is a View in edge elevation of the attachment per se showing it fastened on the tool bit.

Figure 3 is a view at right angles to Figure 12 observing same in a direction from right to left.

l igure 4 is a section on the line 4-4 of Figure 3, looking in the directon of the arrows.

Figure 5 is a view of Figure 2, observing same in a direction from left to right and employed to bring out the adjustable mounting of the plate on the body.

Referring now to the drawing by distingushing reference numerals and attention being had to Figure 1, it will be seen that the reference character A designates, in a general way, the headstock of a conventional lathe having associated therewith the usual collet B with the stock or work C removably and adjustably clamped in said collet and extend ng centrally therefrom. The frame structure D includes supporting guides E for the shiitable carriage structure F. The letter G designates the so-called compound, while H denotes a single style tool post and T, the regular or standard tool or tool bit. The tool is shown adjustably supported in the tool post with its cutting end J located in cutting relationsh p to the tip K of the stock or work C. The improved pilot turning attachment, as a unit, is denoted by the numeral 8. In Figure 1 this is shown occupying complete operative positions, the same connected at one end to the tool T and at the opposite end to the stock C. We might add that the cross slide, which is also shown, is denoted by the letter L.

It is obvious that the invention is difierentiated,

as an entity, by the numeral '8. As before indicated, it comprises a block-like body Q, this of rectangular form as shown in Figures 2 and 3, the same having a groove it! in one side forming a key-way for the shank H of the cutting tool. The cutter end J projects beyond the groove in the block and the parts are assembled and held together by set-screws [-2 in the block or body securing the tool in the key-way or groove. The so-called plate, which is of the shape shown in Figure 3, is denoted by the numeral 113. This fits in the grooved or shouldered portion 14 of the body or block s. As shown in F gure '5, elongated slots t5 are provided in the plate on one side and the plate is countersunk around the slots as indicated at Ilia. These slots l5 serve to accommodate bolts it thread-ed into sockets provided in the block or body 9. The slot connections serve to adjustably mount the plate on the body and make allowances for subsequent adjustments necessary to bring about centering of the plate respect to the body. The plate, as shown in Figure 4, is provided with a piloting aperture or circular hole I! for the stock and also the plate is Figs. 1 and 3, to restrict or concentrate the field adjacent the tube neck and hence the beam countersunk as at IE to provide a circular recess to accommodate the roller bearing unit 9. The unit includes an inner race 29 of a proper diameter to snugly receive and surround the stock, as shown. Thus, the stock is supported in the inner race 29 or the ball bearing, rather than in the aperture H.

In operation an ordinary three-eighths inch tool bit is placed in a single or four-way tool post (not shown) in the usual manner and is located on center. After taking several cuts in getting a cross-slide reading on the diameter desired, an attachment 8, that is, a pilot turning attachment, of the necessary size is selected. The complete attachment is then placed over the tool bit as shown in Figure 1 and positioned by sliding forward or back on the tool bit with the clamping screws !2. When the pilot is over the stock properly with the stock extending through the bearing or rather the inner race 29, the screws 12 are tightened. Thus, the parts are set up for coaction and operation as shown in Figure 1 of the drawings.

It will be appreciated, having studied the drawings in conjunction with the description, that the attachment as a unitary assemblage, is easy and quick to apply and adjust. The desired size on the'cut is arrived at by feeding the cross-slide rather than tapping the tool bit as is in the case of the conventional two-roller type turner. The attachment permits heavier cuts with greater certainty of size and substantially eliminates drift of small diameter stock, permitting a piece of almost any length to be satisfactorily held and turned. The attachment has its greatest use in the large quantity of production of small pins, studs, etc. i

So far as we have been able to ascertain, as a result of studied consideration of the specific field of invention under advisement, no one prior to us has devised and used a pilot turning attachment for lathes which is characterized by a simple economical, rectangular metal block or body which has a centralized groove functioning as a channel and opening through opposite ends'of the body to seat a correspondingly shaped tool bt wherein the bit, when inserted in the groove or channel is allowed to extend through and beyond both ends of the channel with one end to coact with the work piece and the other end to be supported, in the usual way, in a conventional-type tool post, the connection between the body and shank of the tool bit being effected by simple set screws. We emphasize this because .we utilize the tool bit as the sole support for the block-like body. Secondly, the connection between the shank of the bit and the body is not only adjustable so that the body may be slid lengthwise along the shank of the tool bit, but the connection between the body and the bit is separable. This allows the body to be detached, making it possible to remove our entire unit from the tool bit expediently while further cuts of a different nature are made by the same tool bit. What is more, novelty is predicated upon the notched end portion of the body which provides a shoulder and ledge for our novel plate. This is such that the two parts couple together nicely as brought out especially in Figures 2 and 4 of our drawings. Also, we emphasize the bolt and slot connection between the parts 8 and 9 thus positioning the plate 8 0n the side of the body opposite to the point of anchorage of the tool bit. Thus, the plate with its bearing is offset and lies in a plane spaced in parallelism from the projecting end J of the bit as brought out to advantage in Figure 2 of our drawings. What is more, the bolt and slot connecting means allows the bearing means, particularly the inner race 29, to be centered in relation to the work and tool bit. Consequently, the body 9 is adjustable and detachable in relation to the tool bit and is supported wholly by the tool bit, The plate carrying the bearing is ofiset as shown in Figure 2 and is detachable and also adjustable in relation to the tool bit and body 9.

Minor changes in shape, size, materials and rearrangement of parts may be resorted to in actual practice so long as no departure is made from the invention as claimed.

We claim:

1. A pilot turning attachment for lathes comprising a rectangular block-like body having flat forward, rearward and marginal surfaces and provided in its rearward surface with a groove opening through opposite marginal edges and. provided with set screws projecting into said groove, said groove being adapted to receive the shank portion of a tool bit, a tool bit having its shank portion nested in said groove and held in place by said set screws, said tool bit constituting the sole support for said body, said body being detachable and adjustable in relation to the tool bit and one projecting end of the tool r bit being adapted to be mounted in a conven tional tool post, a plate detachably and adjustably mounted on the forward surface of said body and projecting. beyond the adjacent marginal edge, said plate having a centered anti-friction bearing adapted to completely embrace and steady the free end of the stock to be turned and cut by said tool bit, said bearing being eccentric to the longitudinal axis of said tool bit and lying in a plane in spaced parallelism in relation to the adjacent end of said tool bit.

2. The structure specified in claim 1 wherein the stated forward surface of said body has an open ended notch providing a shoulder and ledge, the coacting portion of said plate abutting said shoulder and slidably contacting said ledge and having bolt slots, said slots being at right angles to the longitudinal axis of the tool bit, and bolts fitted through said slots and anchored in said ledge to allow the plate and its bearing means to be shifted in respect to the body for centering the bearing means in relation to the tool bit.

DONALD DU BOIS.

PERCY WHEELER,

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

UNITED STATES PATL NTS Number Name Date 238,509 Hoffman Oct. 19, 1880 1,161,056 Liebstein Nov. 23, 1915 2,373,301 Erickson Apr. 10, 1945 2,420,945 Gaylord May 20, 1947 FOREIUN PATENTS Number Country Date 133,154 Great Britain Oct. 3, 1919