Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS3590490 A
Publication typeGrant
Publication dateJul 6, 1971
Filing dateJun 13, 1968
Priority dateJun 13, 1968
Publication numberUS 3590490 A, US 3590490A, US-A-3590490, US3590490 A, US3590490A
InventorsColeman James A
Original AssigneeColeman James A
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Feeler gage having plastic feelers
US 3590490 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent James A. Coleman 12209 Sock: Ave., Cleveland, Ohio 44120 736.746

June 13, 1968 July 6, I971 Inventor Appl. Nov Filed Patented FEELER GAGE HAVING PLASTIC FEELERS 3 Claims, 6 Drawing Figs.

US. Cl 33/168 Int. Cl G01b 3/30, GOlb 3/32 Field of Search 33/162,

l68, 168 B, 80, 81; 24/26l DS; 30/335, 336, 338, 329;40/1l, ll A [56] References Cited UNITED STATES PATENTS 1,661,701 3/1928 Michler 33/168 2,143,343 1 1939 Cooper 40 11 2,237,378 4 1941 Thienemann.. 33/168 2,654,957 10/1953 Grant 33/l68 FOREIGN PATENTS 885,167 l2/l96l GreatBritain .I

Primary ExaminerLeonard Forman Assistant Examiner-Steven L. Stephan Att0meyRichard MacCutcheon ABSTRACT: A feeler gage for ignition points, and the like, comprises a metal handle having at its end a spring clip for holding any one of an associate plurality of individual, tapered, highly-flexible gage feelers of plastic material.

FEELER GAGE HAVING PLASTIC FEELERS BACKGROUND OF THE INVENTION This invention relates to a gap thickness feeler gage.

In the past independent pivotable leaves of metal or a single lengthwise tapered (and graduation marked) metallic tool has been used for measuring and adjusting spark gaps. The single tool is hardly flexible at all, and even if the pivotal (or otherwise sorted) individual gage leaves" of metal are somewhat flexible, they are not flexible enough to get around corners without distorting a reading or adjustment; they do not gives;" and they do not transmit an optimum feel to the human operator.

DESCRIPTION OF PREFERRED EMBODIMENT An object of the present invention is to provide simple and inexpensive means, for overcoming the above mentioned difficulties.

Other objects and advantages will become apparent and the invention may be better understood from consideration of the following description taken in connection with the accompanying drawings, in which:

FIG. 1 is a plan view ofa highly flexible feeler according to one aspect ofthe invention;

FIG. 2 is a front edge view of the feeler of FIG. 1;

FIG. 3 shows a similar feeler held in a spring clip associated with a metal handle according to another aspect of the invention;

FIG. 4 is a front view of the for-use" spring clip of FIG. 3, but before its assembly in the handle;

FIG. Sis a side view of the spring clip of FIG. 4, and

FIG. 6 shows a portion of a display card or board for holding various ignition point feelers and a handle.

SUMMARY OF THE INVENTION flexible or rubberlike material. Related to this aspect is a novel spring clip means for mooring any one of plural such feelers to a handle.

DESCRIPTION OF PREFERRED EMBODIMENTS As is well known, if ignition points are too close, firing may be too soon (with insufficient voltage and current to saturate a coil or cause proper combustion), while if they are too far apart the dwell may be insufficient, even to the extent of having to push the vehicle in order to start it. Prior art longitudinally tapered wedge gages as in Frauenholtz U.S. Pat. No. 2,882, 605 are somewhat disadvantageous because they are unyielding and because their use requires considerable free space for manipulation. Prior art feeler leaves individually pivotal (like blades of a jackknife) are well-known but they too, being of steel, are hard to feel" with and require a perfeet (i.e., initially flat) fit for accuracy.

To obviate these difficulties, the present invention suggests individual feelers which are nonmetallic, such as many natural or synthetic plastics or other materials such as a rubber which is flexible but not particularly stretchable. Preferably the material is hard (relatively high on Mohs scale) so that it is not easily scratched by the metals of conventional electrical points." Still it must not be too brittle or adversely affected by temperature changes likely to be encountered. Fish paper seems workable except for its high cost. Celluloid is usable, and good results are achieved using polyvinyl chloride which is commercially available as sheet stock in various thicknesses which are slightly oversize as regards nominal dimensions, e.g. of:

0.010 inches 0.015 inches 0.020 inches 0.025 inches After selecting the feeler material, which will be assumed to be polyvinyl chloride sheets in each of the above nominal thicknesses, individual feelers, such as that shown at 10 in FIG. I, are cut in plural numbers from each of the thicknesses. One end is preferably angled off as by a slant side 108 to provide less width at ultimate gaging end as compared to the opposite and ultimately held end (see FIG. 3). This also permits each gaging end to be small while the remainder of the feeler has adequate room forwidentifying indicia (as shown) if such be desired. As a next step the gaging end 100 of each feeler may be knurled to roughen the end, or ground, or squeezed in a press, all of which seem to toughen the end. Additionally, for some reason knurling seems to raise the thickness dimension while both grinding and squeezing tend to lower the thickness dimension, so that these procedures can be selectively used to bring the nominal sizes above mentioned into desired gage thickness, for example:

0.010 inches 0.015 inches 0.016 inches 0.017 inches 0.018 inches 0.019 inches 0.020 inches 0.025 inches As a next step I prefer to crestinge (omamentally design) one or both sides of each feeler as this makes it more decorative and also seems to toughen the sheet material, though the order of the step may not be important and it might have been the whole of the original stock which was crestinged instead.

As a next step I prefer to taper grind the gaging end 100 toward the back as shown by the line 10T in FIG. 2. This puts an advantageous feel in the feeler gage and appears to give a novel Go-No Go" advantage.

As already intimated, the order of steps is not of particular importance and the feelers could be cut to the point as a final step, either in plan view (FIG. I) l or elevation view (FIG. 2). And as a later or prior step, individual feelers can be provided with holes 10H as for retaining them in storage on a snap ring I3 later to be described in connection with FIG. 3.

Even though plastic is easier to mark than metal, any identifying printing might become obscured by grease from the operatorhands after some use and I prefer to color codethe individual feelers as indicated by the standard (Patent Office) hatching for green in FIGS. 1 and 2 and for blue in FIG. 3, Painting, to achieve this result, may readily be applied to the plastic.

An assembled gage as shown in FIG. 3, has a metal handle portion 11 which,,-to supplement the light weight of the nonmetal (e.g., plastic) feelers, is conveniently a substantially hollow tube of aluminum. Handle 11 carries a convoluted spring steel (e.g. piano ivire) hold for use clip 12, as well as (optionally) a spring wire clip 13 (for storage of unused feelers at the opposite side end of the handle).

As shown in FIGS. 4 and 5, the clip 12 may be made ofa single piece of wire having end portions 121.. and 12R, for the most part ultimately buried in, and preferably soldered in, a hole in the handle. The clip 12 wire is formed to provide a pair of outer (feeler gage edge) guides 126, and is shown having front to back vertical portions 12V and back to front angled portions 12A cooperating to securely hold the selected feeler 10. The spring 12 clip has the advantage it will hold any one of, for example, 16 different gage feelers, each very tightly despite substantial differences in thickness dimensions. The convoluted spring wire clip is remarkably convenient to use and has the advantage over the prior art arrangements (of pivotal leaves or snap-on, dress-type, fastenings) of not concentrating force on one small area of the plastic newly used for feeler gage application.

As seen in FIG. 6 a metal, wood or cardboard support backing 15 may hold a handle part as shown at 11' and various feelers 10 may be mechanically tied to the board of backing 14 by rubber of other material straps 15 and visually corelated with boardl or straps 15 (or both) by suitable indicia, as

shown, or by color coding or, because some people are color blind, or because grease accumulations tend to obscure alpha numerics, by both lettering and color. Optionally, too, both the snapring 13 (FIG. 3) and the board 14 (FIG; 6) could be provided, so the user could decide just where and how he will store feelers not in immediate use.

There is thus provided an arrangement of the class described capable of meeting the objects of the invention which is about five ways better because of: super flexibility, the Go-N Go feature, the positive feel even when the feeler must go around the corners, the feature drag, and the close tolerances which can be achieved, all of which provide about five better ways for curing hard starting, rough idling, poor acceleration, spark ping, and low gas mileage.

The ability of the suggested feeler material to go around corners means less possibility of opening the gap gage sought to be measured. Additionally, the invention provides a construction which is of light weight and low cost and really capable of transferring feel of the situation to the human operator particularly where the gap to be gaged is hidden from view. Perhaps one of the requisites is that the flexibility of the feeler material be greater than that of the spring against which points may be opened, since only this can assure not giving a wrong reading. Nonmetal feelers serve this end; conventional ones of steel do not. Additionally, nonmetal feelers are easier to color or otherwise identify and each nonmetal feeler can readily be made flexible enough so that it will square itself with gap limits rather than changing those limits just because the human operator can not or does not hold his feeler square.

Of course, instead of simply obviating or having any painting step, plastic sheet stock which is colored throughout might be used, for while l have illustrated and described particular embodiments, various modifications may obviously be made without departing from the true spirit and scope of the invention which I intend to have defined only by the accompanying claims taken with all reasonable equivalents. It should be understood that, for clarity, the drawing is not-to-scale, particularly as to feeler thickness in H0. 2.


1. A feeler gage comprising a metal handle portion, and a plurality of more than two flexible feelers, each having substantially the same width, and which difier operatively from one another in thickness and which additionally differ visually from one another according to added indicia substantially distinguishable by the unaided human eye, said handle portion including a plurally convolute spring means, which, when the handle is generally vertical, includes a wire with a horizontal section shorter than the width of the feelers, and having right angular extensions which extend upward at each end of the horizontal section, each extension being shorter than the feeler, each extension flared outwardly then turned back upon itself to loop behind, and then extending downwardly and passing forward of the horizontal section so that the spring means can hold a feeler to be used for gauging.

2. A feeler gage as in claim 1 further characterized by the readily legible identifying indicia including color coding.

3. A feeler gage as in claim 1 further characterized by the feelers each having a width dimension and a minor dimension of thickness and being frusto tapered as to width to provide a small width for gaging and a greater width for handling, identifying and the like, and being in part and tapered as to thickness to provide a small thickness for entry and a greater thickness for gaging.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 590 490 Dated July 6 1971 Inventor(s) James A. Coleman It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the cover sheet [72] "Socka Ave" should read Soika Ave Column 1, lines 13 and 14, "gives" should read give Column 2, line 9, cancel the blotch; line 72, "15" should read 14 line 74, "of" should read or Column 4, line 29, before "tapered" insert frustatively Signed and sealed this 23rd day of May 1972.

(SEAL) Attest:


Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1661701 *Aug 17, 1927Mar 6, 1928Michler Robert WThickness gauge
US2143343 *Oct 26, 1936Jan 10, 1939Morris CooperCombined advertising device and card holder
US2237378 *Apr 21, 1938Apr 8, 1941Teletype CorpAssembled gauge
US2654957 *Sep 29, 1950Oct 13, 1953Grant Lee AFeeler gauge
GB885167A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7735236Apr 9, 2008Jun 15, 2010Ileogben Pius OPulley gauge
U.S. Classification33/562
International ClassificationG01B3/30, G01B3/32
Cooperative ClassificationG01B3/30, G01B3/32
European ClassificationG01B3/30, G01B3/32