US2403382A - Slide rule - Google Patents

Description

Patented July 2, 1946 UNITED STATES PM'ENT oEFlcE SLIDE RULE Samuel Lerner, Pawtucket, R. I.

Application March 20, 1944, Serial No. 521,296

(Cl. 23S-70) 1 Claim.

This invention relates to a slide rule, more particularly to the physical form of the slide rule.

Slide rules are usually in the form of a flat elongated shape with scales on the opposite flat surfaces and with a slide capable of being turned over for cooperation with the scales on either fiat surface.

One of the objects of this invention is to provide two telescoping members, the outer of which carries a scale and is transparent while the other cooperates therewith that the parts may be held together by reason of their nesting relation.

Another object of the invention is to make available shifting from one scale to the other by merely turning the members about their common axis, whereby all of the scales provided will be equally prominent when the device is rotated from one position to another.

Another object of this invention is to provide a compact arrangement of the parts and an arrangement so that the device may be readily held in the pocket of the user to be carried on the person.

A further object of this invention is to provide an arrangement of the parts so that the physical structure may house parts for other uses, for instance as a pencil or the like.

Another object of this invention is to provide for changing the size of the scale surface by a modification of the diameter of the cylinder rather than to change the width of a flat device as heretofore usually used.

With these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described and particularly pointed out in the appended claim.

In the accompanying drawing:

Fig.1 shows my rule as applied to a pencil;

Fig. 2 shows-the cylindrical pencil body;

Fig. 3 is an elevation of the tubular slide which may be telescoped on the body;

Fig. 4 is an end view of the structure shown in Fig. 3;

Fig. 5 is a section on line 5-5 of Fig. 2;

Fig. 6 is a section of the slider alone;

Fig. '1 is a sectional view on line 1-1 of Fig. 1;

Fig. 8 is a longitudinal sectional view of the cursor;

Fig. 9 is an end view showing a modied form of slide.

With reference to the drawingJ have provided a cylindrical body I0 which as here shown has the form of a mechanical pencil with its shell tapered at one end II within which shell the mechanical pencil structure may be housed for the projection of a lead I2, while an eraser I3 may be provided at the opposite end of the body. Scales designated generally A and designated generally D are laid off in logarithmic values on the surface of the body I0.

A slide designated generally I4 comprises a transparent cylindrical member through which the A and D scales on the body I0 may be viewed. Its internal diameter I5 is of a size to slidingly fit the outer cylindrical surface I8 of the body I0. This member carries on its surface engraved marking designated as the B, C, and Cl scales, as shown in Fig. 3, to cooperate with the scales A and D and may carry additional scales at .|1, I8, and I9 as shown in section in Fig. 4.

In order to maintain the members III and I4 in adjusted relation grooves 29 and 2| are provided in the body I0 for the reception of resilient leaf springs 22 and 23 located adjacent either end portion of the member I4. These springs will fit into either of the grooves 20, 2l and maintain the members in relative position against rotation so that they may be slid one on the other. If it is desired to relatively move the slide through the resilient portions 22 and 23 will be transferred from the groove 20 to the groove 2|.

In some cases instead of having the seamless tube I4 for one member the tube may be formed as shown at 25 in Fig. 9, of a fiat sheet so as to provide overlapping portions 26 while the resilient retaining springs 21 will be provided at the overlapping portions. In some cases this part 21 may be fixed and the resiliency of the stock depended upon for holding the tubular member adjusted pon the body.

The cursor or third member designated 30, as shown ln-Fig. 8, consists of a transparent cylindrical. member 3| having a resilient spring 33 for friction` against the member I4 upon which it slidingly fits and may be moved therealong. Datum lines 32 on the outer surface and 32' on the inner surface of the member 3l are provided for convenience of the eye in determining a certain position on the scale for easy reading. A finger clip 34 is resiliently mounted as at 35 and may be swung outwardly at its knob end 36 by pressure on the piece 31. The knob end will also move along and engage the member I4 for friction therewith and may also be used as a clip for retaining the entire device in the pocket of the user when desired.

'Ihe members I0 and I4 may be relatively moved for determination of desired calculations, the slider being moved to assist in reading. The datum line 32 on the outer surface of the slider 3 is aligned with the datum line I2' on the inner suriaeethereofwhenrcadingthsscalessolsto avoid parallax in observation through the slider il and through the slide il.

I claim- A calculating instrument comprising a cylindrical body member, having a scale thereon, a transparent cylindrical tubular member having a bore of a size to slidingly tit said body member,

4 telescoping thereover and having scale thereon cooperatingr with the scale on the bow, and a cylindrical cursor member of transparent material slidably fitting said tubular member and having two datum lines one on its inner surface and the other on its outer surface, said lines being in a plane at right angles to the scales on said body and cylindrical members.

SAMUEL LERNER.

Images