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Publication numberUS412952 A
Publication typeGrant
Publication dateOct 15, 1889
Filing dateNov 2, 1888
Publication numberUS 412952 A, US 412952A, US-A-412952, US412952 A, US412952A
InventorsCharles Elterich
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Charles elterich
US 412952 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

(No Model.) l



No. 412,952. Patented Oct. 15, 1889.'

` N. PETERS, Pimerlinhcmphmwnnhingwn. u. c.



SPECIFICATION forming part of Letters Patent No. 412,952, dated ctober 15, v1889. l Application filed November 2, 1888. Serial No, 289,852. (No model.)

. To all whom it may concern:

BE it known that I, CHARLES ELTERICH, of New York, in the county and State of New York, have invented a certain new and useful Improvement in Taps, of which the following is a specification.

My improvement consists in a tap which is longitudinally grooved at a number of points from end to end, so as to have a number of isolated longitudinal ribs or salient port-ions extending from end to end, the latter being screw-threaded from end to end of the tap.

My improvement also consists in the combination, with such a tap, of a block having a screw-threaded cavity adapted to receive and hold the tap, and having combined with it a set-screw or adjustable pin capable of engaging with one of the grooves of the tap to hold it against rotation. This block may be secured in any suitable holder or chuck.

In the accompanying drawings, Figure l is a side view of a tap embodying my improvement. Fig. 2 is aview of the same and the block with which itis engaged. Fig. 3 is an end view of the tap and block. Fig. 4 is a side view of the tap and a longitudinal section of the block and holder.

Similar letters of reference designate corresponding parts in all the figures.

A designates the tap. It is formed with grooves d, which extend longitudinally of it at a number of' points from end to end. Between these grooves are a number of ribs b. These also extend longitudinally of the tap from end to end. They are shown as tapering slightly at one end; but this is not indispensable. The ribs are screw-threaded from end to end. The tap is therefore substantially uniform from one end to the other.

B designates a block, shown as of circular form, and having a smooth periphery. It may be made of any suitable metal. The center is provided with a screwthreaded hole, into which the tap may be fitted and with which the t-ap may engage. By rotating the tap within the block the tap may be made to project more or less beyond the block at the end which is to be used. When it is adjusted to the desired point, it may be secured in position by a screw or screws c, extending radially through it and engaging with one or more of the grooves a of the tap. Such screw or screws will serve to secure the tap in position relatively to the block by preventing the tap from rotating.

C O2 designate a holder, consisting of a body C and a shank or handle C2. This holder is provided with a cavity d, capable of receiving the block B, and also with a cavity d', into which the inner end of the tap A may extend. The block B may be secured in the cavity CZ of the holder by one or more screws inserted into the holder, engaging with the screw-threads in the holder and extending into the block B. It will be seen that the tap may be adjusted more or less beyond the block.

The tap described may be used at either end. If broken, the remaining part may still be used. EvenV a .short piece can be used with the block B.

It is advantageous to employ a tap only of the necessary length, because the shorter the tap the less it is subject to dangerous strains. I provide for using a tap of only the necessary length, because it can always be adjusted beyond the block B exactly to the extent that is required for any particular purpose. Moreover, it is desirable to extend simply the length of the tap, which is necessary for any desired operation, beyond the block, for the reason that thus the block may serve as a gage for the depth of the work to be performed by the tap. If the tap should be warped or bent longitudinally, this will not be so prejudicial, because as the tap may be shortened to the length necessary for operation the evils of a longitudinal bend will be reduced to a minimum, and as the tap will be held in the block close to the projecting operative portion by its own screw-threads the evils of a bend will be less than if the tap were otherwise held.

'What I claim as my invention, and desire to secure by Letters Patent, is

The com bination,with a tap screw-threaded throughout its length, of a holder having a cavity and the hollow shank, a block smooth on its periphery and having a threaded hole to receive the tap, and a screw or pin tted in the block and engaging with the tap, substantially as specified.





Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2424113 *Aug 30, 1946Jul 15, 1947Plan O Mill CorpTap and holder therefor
US3531810 *Sep 25, 1969Oct 6, 1970Clarence J FureTapping tools
US3552503 *Feb 7, 1969Jan 5, 1971Lebar Charles SDrill and clean-out for blind holes
US4412764 *Nov 10, 1980Nov 1, 1983Wawrzyniak Walter WDouble ended tap
US4526542 *Feb 6, 1984Jul 2, 1985Robert KochisDental burr and method of preparing a tooth
US5890897 *Jul 22, 1996Apr 6, 1999Kruger; Bernard M.Adjustable length drills
US6951562Nov 13, 2002Oct 4, 2005Ralph Fritz ZwirnmannAdjustable length tap and method for drilling and tapping a bore in bone
US7163542Mar 30, 2004Jan 16, 2007Synthes (U.S.A.)Adjustable depth drill bit
US7569058Sep 7, 2005Aug 4, 2009Synthes Usa, LlcAdjustable length tap and method for drilling and tapping a bore in bone
US8197481 *Jul 13, 2009Jun 12, 2012Synthes Usa, LlcAdjustable length tap and method for drilling and tapping a bore in bone
US9572589Jul 10, 2012Feb 21, 2017Stryker European Holdings I, LlcDrill guide
US20040092940 *Nov 13, 2002May 13, 2004Zwirnmann Ralph FritzAdjustable length tap and method for drilling and tapping a bore in bone
US20050222571 *Mar 30, 2004Oct 6, 2005Ryan Christopher JAdjustable depth drill bit
US20060004372 *Sep 7, 2005Jan 5, 2006Synthes(Usa)Adjustable length tap and method for drilling and tapping a bore in bone
US20090275949 *Jul 13, 2009Nov 5, 2009Ralph Fritz ZwirnmannAdjustable length tap and method for drilling and tapping a bore in bone
Cooperative ClassificationB23B51/05