US2823859A - Reeling device - Google Patents

Description

Feb. 18, 1958 R. sTocK 2,823,359

REELING DEVICE Filed March 6,- 1953 2 Sheets-Sheet l %l j A moll f l Robert .5700( BY W. ATOREYS Feb. 18, 1958 R. s'rocK 2,823,859

REELING DEVICE Filed March 6, 1953 2 Sheets-Sheet 2 LNVENTOR Robert 5706A f /fdf ATTURNEYS AUnite tetes Patent O REELING DEVICE Robert Stock, Montreal, Quebec, Application March 6, 1953, Serial No. 340,857 7 Claims. (Cl. 235--"i1) This application is a continuation-inpart ot my copending patent application Serial No. 133,375, tiled December 16, 1949, now U. S. Patent No. 2,714,492, dated August 2, i955.

The present invention relates to a reeling device more particularly intended as a slide rule structure which enables the construction of a slide rule having a greater accuracy than slide rules of ordinary sizes.

The slide rule structure, according to the invention form a computing device which comprises a ileXible scale bearing sheet member wound on two reels and slidable relatively to a stationary sheet member also bearing scales adapted to be read in conjunction with those of the slidable sheet member.

Due to the tact that the movable sheet member has a substantial length, the device, according to the invention, permits of solving mathematical problems with much greater accuracy than ordinary size slide rules. Namely, it will reach an accuracy of four to ve igures.

Another important object of the present invention is the provision of a computing device of the character described in which there is no play between the rotational movement of the reels and the longitudinal 'travelling of the movable sheet member and especially when the direction of travelling ot said sheet is changed.

An important object of the present invention is the provision of a computing device of the character described which will enable the displacement of the movable sheet member in small increments in order to obtain an accurate setting ot t. e graduations of said movable member relatively to the graduations of the stationary sheet member.

' Yet another important object of the present invention is the provision of a device of the character described which is very simple in construction and which will give a prolonged service.

The foregoing and other important objects of the present invention will become more apparent during the following disclosure and by referring to the drawings in which:

Figure 1 is a perspective view of a rst embodiment of the computing device according to the invention;

Figure 2 is a longitudinal section of the saine, taken along line 2-2 of Figure 3;

Figure 3 is a cross-sectional along line 3-3 of Figure 2;

Figure 4 is a diagrammatical longitudinal section of a second embodiment according to the present invention; and

Figure 5 is a cross-section along hne 5-5 of Figures 2 and 4. y

Referring now more particularly to the drawings in which like reference characters indicate like elements throughout, the computing device, according to the invention, comprises a casing the slanting top 2 of which hasa rectangular opening which is closed by a transparent panel 3 maintained in position by means of the frame 4 screwed to the top 2 by bolts 5. A hat stationary sheet 6 is supported underneath the panel l and is provided a A 2,823,859 Ice Patented Fas. is, e

with a plurality of spaced parallel elongated apertures such as 7 along one or both edges of which are disposed scale graduations.

In an alternative construction, not shown, the sheet member 6 may be dispensed with and the graduations may be directly marked on the panel 3, in which case said panel would be partially opaque.

A sheet of iiexible material 11, such as paper, is displaceable underneath the stationary sheet 6 and bears scale graduations such as adapted to show through the elongated apertures 7 of the stationary sheet 6 and are adapted to be read in conjunction with the scale graduations of said sheet 6. The portion of the flexible sheet 11 in contact with the stationary sheet member 6 is supported by a plate 1S which may be secured to the sides 1 of the casing 1 by brackets 16, or which may be integral with said casing. This plate 15 is preferably provided with elongated ribs 17 (Figure 3) in alignment with apertures 7 to raise the scale bearing portions of the slidable sheet 11 in order to avoid parallax while reading the scales.

Referring to Figure 2, the ends of the sheet 11 are respectively secured to and wound around two spaced parallel reels or cylinders 18 and 19 of equal diameter.

The cylinder i8 is located at the top rear portion of the casing 1 and is mounted on a shaft 20 journalled in the sides 1 of the casing 1.

Also mounted on said shaft 2i) is a pulley 21 rigid with the cylinder 1S.

Instead of having the shaft 26 journalled in the side walls l', the cylinder 1S could be rotatably mounted on said shaft or said cylinder could be rotatably mounted on pointed screws.

A shaft 23, which is journalled in the side walls i at the front portion of the casing 1, supports the cylinder 19, the latter being secured to said shaft. The shaft 23 projects through the side walls of the casing to mount the manipulating knobs 27 as shown in Figures l and 5. A pulley 24 is freely rotatable on the shaft 23 and has a. diameter greater than the diameter of the pulley 2l associated with the cylinder 1S. An endless beit 22 is trained over the pulleys 21 and 24 and is capable of slipping on said pulleys. A ratchet wheel 3l? is rigidly secured to or made integral with the pulley 24. A pawl 32 is pivotally mounted on the cylinder i9 and is engageable with the teeth of the ratchet wheel Sil.

Finally a brake lever 33 pivoted to a side wall l of the casing at 34, is urged against the periphery of the cylinder 18 by means of the coil spring 35.

ln the arrangement described, it is apparent that the cylinders 18 and 19 rotate at an equal peripheral speed in either direction due to the connection consisting of the sheet 11. These cylinders rotate also at an equal angular speed due to their equal diameters. But pulley 2l will rotate or tend to rotate at a greater angular speed than free pulley 24 due to its smaller diameter.

Referring again to Figure 2, upon clockwise rotation of the knob 27 to wind the sheet l1 around the cylinder' 13, the pawl 32 mounted on the positively driven cylinder 19, engages the ratchet wheel 3), and the pulley 24 and belt 22 tend to rotate the cylinder i3, through smaller diameter pulley 2l, at a greater peripheral speed than is allowed by the sheet 1l unwound from cylinder i9, whereby said sheet il is maintained taut during this rotation and slipping occurs between belt 22 and at least one of the pulleys 21 and 24.

Counter-clockwise rotation of the knob 27 causes the positive rotation of cylinder 19 which winds the sheet il against the frictional force exerted by the brake lever 33 on the periphery of cylinder 18, as said sheet 11, due to the respective diameters of the cylinders and pulleys, causes the belt 2?. to rotate the pulley 24 at a slower angular speed than the angular speed at which the cylinder 19 is rotated, the pawl 32 being thus disengaged from the ratchet wheel 39. When the knobs 27 are not rotated, the brake lever 33 maintains the system in the position of the last setting.

Although the equality ofthe overall diameters of the cylinders 1S and 19 is not maintained in the course of operation due to the thickness of the sheet il wound on said cylinders, the above explanation holds within certain limits of said thickness depending on the relative diameters of the pulleys 2l and 24. The above described arrangement ensures a constant tension of the sheet in both directions of travel and eliminates any slack or play in said sheet upon reversal of its direction of movement. Thus said sheet il may be positioned with great accuracy in order to obtain an accurate reading of the cooperating scales inscribed on the members 6 and ii. The machine is provided with a bottom aperture 36 normally closed by'a plate 37screwed at 38 to the casing l. Said aperture is used to reach the internal elements of the device for dismounting or other purposes. The machine may rest on suitable foot pads 39.

Figure 4 shows still another embodiment according to the present invention which is similar to that of Figure 2. It differs therefrom only in the relative diameters of the cylinders and pulleys. More particularly, the pulleys 21' and 24 have the same diameter but the cylinder 18 associated with the pulley 21 has a larger diameter than the cylinder 19' associated with the pulley 24.

Clockwise rotation of the shaft 23 positively rotates the ratchet and associated pulley 24 through the cylinder 19 and pawl 32 as slipping occurs between the belt 22 and its associated pulleys due to the fact that said belt tends to rotate the cylinder 18 at a greater peripheral speed than is allowed by sheet 1l unwound from cylinder i9', whereby said sheet 11 is wound on cylinder 1S and is maintained taut.

Anti-clockwise rotation of the shaft 2.3 by the knob 27 positively rotates the smaller diameter cylinder 19 which winds the sheet Irl against the frictional force exerted by the brake lever 33 on the periphery of the larger cylinder 13', as said sheet ll, due to the respective diameters of the cylinders and pulleys, causes the belt 22 to rotate its associated pulley 24 at a slower angular speed than the angular speed at which the cylinder 19 is rotated the pawl 32 being thus disengaged from the ratchet wheel 39. Said brake lever 33 Ialso maintains the system at rest when the knobs 27 are not rotated.

While preferred embodiments according to the present invention have been illustrated and described it is understood that various modifications may be resorted to without departing from the spirit and scope of the appended claims.

I claim:

l. A reeling device comprising a casing, two reels of unequal diameter rotatively mounted inside said casing at the ends thereof for rotation in two directions, a sheet member having its ends respectively Secured to and wound on said reels, braking means applied to the larger di ameter reel, a shaft on which the smaller diameter reel is rigidly secured, a first pulley rotatable on said shaft, a second pulley secured to said larger diameter reel, at least one knob secured to said shaft for rotating the same, an endless belt trained on said pulleys and capable of slipping relatively to at least one of them, and clutch means for rigidly connecting said smaller diameter reel and said first pulley when said shaft is rotated in a direction to cause the winding of said sheet member on said larger diameter reel and for releasing said rigid connection between said smaller diameter reel and said irst pulley when said shaft is rotated in a direction to cause the winding of said sheet member on said smaller diameter reel, whereby said smaller diameter reel will wind said iiexible sheet member against the frictional resistance ofY said braking means against said larger diameter reel, and said larger diameter reel will Wind said flexible sheet member against the friction exerted by the slipping of said belt on at least one of said pulleys.

2. A device as claimed in claim l, wherein said clutch means comprises a ratchet wheel and a pawl engageable with said ratchet wheel.

3. A reeling device comprising a casing, first and second reels of equal diameter rotatably mounted in said casing at the ends thereof, a sheet member having its ends respectively secured Vto and wound on said reels, a larger diameter pulley coaxial with and rotatable with respect to said first reel, a smaller diameter pulley coaxial with and rigidly secured to said second reel, frictional braking means applied to said second reel, an endless belt trained on said pulleys and capable of slipping relatively to at least one of the same, at least one knob associated with said iirst reel and clutch means for rigidly connecting said larger diameter pulley to said first reel when said first reel is rotated in a direction to cause thewinding of saidV sheet member on said second reel and for releasing the rigid connection between said larger diameter pulley and said first reel when said first reel is rotated in a direction to cause the winding of said sheet member on said first reel, whereby said iirst reel will wind said flexible sheet member against the frictional resistance of said braking means against said second reel and said second reel, will wind said flexible sheet member against the friction .exerted by the' slipping of said belt on at least one of said pulleys.

4. A device as claimed in claim 3, wherein said clutch means comprises a ratchet wheel and a pawl engageable with said ratchet wheel.

5. A reeling device comprising a casing, first and second reels rotatably mounted in said casing at the ends thereof, a flexible sheet member having its ends respectively secured to and wound on said reels, a rst pulley coaxial with and rotatable with respect to said irst reel, a second pulley coaxial with and rigidly secured to said second reel, frictional braking means applied to said second reel, an endless belt trained on said pulleys and capable of slipping relatively to at least one of the same, at least one knob associated with said rst reel and clutch means for rigidly connecting said first pulley to said first reel when said first reel is rotated in a -direction to cause the Winding of said sheet member on said second reel and for releasing `the rigid connection between said rst pulley and said first reel when said first reel -is rotated in a direction to cause the winding of said sheet member on said iirst reel, the relative diameters of said reels and pulleys being such that the reel that is winding said sheet member at a particular moment in one direction will be subjected to a force tending to rotate said reel at a greater peripheral speed than the reel from which said sheet member is unwound and the reel from which said flexible sheet yis unwound at a particular moment in the other direction will be subjected to a frictional resistance whereby said second reel will Wind said flexible sheet member against the friction exerted by the slipping of said belt on at least one of said pulleys and said first reel will wind said flexible sheet member against the frictional resistance of said braking means against said second reel.

6. A device as claimed in claim 5, wherein said clutch means comprises a ratchet wheel and a pawl engageable with said ratchet wheel.

7. A reeling device as claimed in claim 5, further in'- cluding a shaft on which said rst reel and said knob are rigidly secured, said first pulley being freely rotatable on said shaft.

References Cited in the le of this patent UNITED STATES PATENTS 2,109,627 Finch Mar. l, 1938 2,556,563 Townsend lune 12, 1951 2,714,492 Stock Aug. 21, 1955

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