US2870968A - Tablet breaker and dispenser - Google Patents

Description

Jmnz?, 1959 H, HUELDN 2,870,968

TABLET BREAKER ANDl DISPENSER Filed Feb.' 25, 195'? TABLET BREAKER AND DISPENSER Heinrich Hueltlen, La Crescenta, Calif., assigner to Hansen-Lynn Co., Inc., Burbank, Calif., a corporation of California Application February 25, 1957, Serial No. 642,247 12 Claims. (Cl. 241-235) `This invention relates to improvements in dispensers and is particularly concerned with rollers for use in a dispensing device which stores frangible wafer-like tablets and dispenses them singly in fractured form. The rollers in this invention are suitable for use in various types of dispensers and will be shown herein `as used in conjunction with the dispenser which is described and claimed in my copending application entitledDispenser, Serial No. 523,683, filed July 22, 1955.

Such dispensers are commonly used for handling tablets for making effervescent drinks in the treatment of headache, minor stomach upsets and a general feeling of malaise. Such tablets may contain one or more of the following ingredients, namely, aspirin, mono-calcium phosphorus, sodium bicarbonate and citricacid. Such ingredients are highly corrosive and adhere readily to practically any material, particularlywhen exposed to any humidity or dampness. Also, such ingredients have a very high tendency toward caking when crushed or milled. It is extremely `dicult to remove such ingredients from a metallic surface, especially when they have reacted to moist atmospheric conditions.

Accordingly, it is `an object of the inventionto provide a pair of rollers for use in a dispenser which will fracture a tablet into granular segments Without any crushing action to produce line powder or dust. Another object of the invention is to provide such a pair of rollers which will coact to move the tablet therebetween Without crushing the leading edge of the tablet as it is fed into the rollers. provide spaced, complementary concave and convex rollers having wider spacing at their central portions than at their end portions.

It is sometimes the practice to attempt to remove caked tablet dust from rollers byhaving a metal edge rest against the surface of the roller acting as a scraper. lt is another object of this invention to provide a pair of rollers for use in' a tablet breaker and dispenser which does not require such Scrapers. A further object of the invention is to provide such a set of rollers having a plurality of shallow depressions fof particular depth on the surfaces of the rollers whereby adhesion of caked dust is substantially eliminated.

The invention also comprises novel details of construction and arrangements of parts which will more fully appear in the course of the following description.

l. The drawing merely shows and the description merely describes preferred embodiments of the present invention which are given by way of illustration or eX- ample.

ln the drawing:

Fig. l is a side View of a tablet breaker and dispenser embodying the rollers of the invention, shown partly in section along the line 1 1 of Fig. 3;

Fig. 2 is a sectional View taken along the line 2 2 of Fig. l;

Fig. 3` is a partial sectional view taken along the line 3--3 Of Fig. 1;

A further object of the invention is to` 2,870,968 Ptented Jan. 27, 1959 Fig. 4 is an enlarged View of a portion of Fig. 3;

Figs. 5a and 5b show a tablet of the type dispensed by the invention before and after passing between the rollers; and

Fig. 6 is a view of a portion of Fig. 4 showing an a1- ternative embodiment of the invention.

The rollers of the invention are adapted for use in a tablet breaker and dispenser which should include means for feeding tablets to the space between the rollers and means for counterrotating the rollers With the adjacent surfaces of the `rollers moving in a downward direction so as to move the tablet past the rollers. A suitable mechanism for this purpose is shown in Fig. 1 and includes a base 10 having rubber feet 11 on the bottom thereof and a removable housing 12 enclosing the upper portion of the base 10. The base has a at upperportion 13 and a shoulder 14 around the edge thereof, the housing 12 having a corresponding shoulder 15 mating with the shoulder 14 and providing a substantially dust-tight seal between the base and the housing. A groove 2lb in the dat upper section 13 is covered by a plate 21, the plate 21 having a substantially vertical opening 22 therethrough. The upper portion 23 of the opening 22 has a larger cross-sectional area than the lower portion 24, and a ring 25 of exible material, such as rubber, is tted within the upper portion 23. Slidably positioned in the groove 20 is a plate 26 driven by a lever 30 (best shown in Fig. 2) which engages the plate 26 by means of a pin 31. The lever 30 has a boss 32 which pivots in an opening in the plate 21, the lever being urged to the position shown in Fig.. 2 by a spring 34 having one end terminating in an opening 35 in the plate 21 and the other end engaging a slot 36 in the boss 32. The lever 3l) extends through an opening in the housing 12 so that it may be manually reciprocated by an operator.

A cylindrical container 40 is placed within the ring 25 i will be fed between the rollers 51, 52. The roller 52 is mounted on shafts 53 and 53 and the roller 51 is mounted on another shaft 54, thetwo rollers being driven in counter-rotation by mating gears 55, 56 on the shafts 53', 54 respectively. The rollers and shafts are positioned in suitable bearing surfaces provided in the base 16 and in a side block 58 tired in a cavity 59 in the base. The vertical outline of the cavity 59 is shown partly in phantom lines in Fig. 1. The side block 58 is a sliding fit in the cavity 59 and is held in position therein by a screw 59. A plate 61 serves to cover a second cavity 62 through which the shafts S3' and 54 are inserted. The shaft S3 extends through the block 58 beyond the side of the base and a lever 57 is rigidly attached thereto. The end ofthe lever 57 opposite the shaft 53 is provided with a handgrip 60, the lever being manually rotatable through a full circle, as indicated in Fig. 1.

A lower portion 63 of the hopper 5t) has an opening 64 at the bottom thereof. The base 1t) includes a tray section 65 located below the opening 64, the tray being shaped to support a glass 66 and to guide the glass into position below the opening 64. An opening 69 in the upper portion 13 of the` base 10 communicates `with the hopper 50, providing access tothe hopper and the rollers when the housing 12 is removed for cleaning and similar purposes.

In the operation of the dispenser, the container 40 having a number of frangible, wafer-like tablets 70 therein is placed upside down in the ring 25 and the housing 12 is` put in position on the base, the recess 43 engaging the bottom 44 of the container. The now bottommost tablet 71 is in the lower portion Ztl of the opening 22, resting on the plate 26. The plate 26 is dimensioned so that it is a snug fit in the groove 2l), thereby nearly completely sealing off the interior of the container 40 from the surrounding atrnosphere, the ring 25 performing a similar function at the upper end of the opening 22. The lever 30 is moved in a clockwise direction, as viewed in Fig. 2,- by the operator, thereby moving the plate 2d away from the opening24. The tablet 71 then drops down into the slot 20, the depth of the slot 2d being slightly greater than the thickness of the tablet. The lever is then released by the operator and the plate is returned to its normal position by the action of the spring 34, thereby sealing off the bottom of the opening 24. The motion of the plate 26 also pushes the tablet from the slot into the hopper Sil, as seen in Fig. l, the tablet being designated by the numeral 72. The plate 26 has a charrifer 75 on the edge which pushes the tablet into the hopper so that the plate will slide underneath the next tablet above.

Aftervreleasing the lever 30, the operator then rotates the lever 57 in a counterclockwise direction, as viewed in Fig. l, thereby running the tablet 72 between the rollers 51, 52. The fractured segments of the tablet fall through the opening 64 into the glass 66.

The desirable operation of the tablet breaker and dispenser is achieved by the design of the rollers which will be described in detail. The roller 51 has a concave surface of revolution and the roller 52 has a convex surface of revolution, this form best being seen in Fig. 4. The rollers are spaced so that the minimum distance between the surfaces thereof is at least as great as the thickness of the tablet which is to be dispensed in the mechanism, thereby preventing any portion of the tablet from being crushed between the surfaces of the rollers. However, the curvature of this space between the rollers requires that the tablet be fractured into a plurality of smaller segments in order to pass between the rollers. lt is preferable that the space between the corresponding surfaces ofthe roller be only slightly greater than the thickness of the tablet being fractured so that the fragments will be of a minimum size, since the size of the fragments increases as the width of the space between the surfaces increases.

When a tablet is entering the space between the rollers, such as is shown by the tablet 72 in Fig. l, the tablet will be first engaged by the central portion of the rollers and then will be pulled downward between the rollers as they continue to counterrotate. lt has been found that if the space between the central portions of the rollers is made slightly greater than the space between the end portions of the rollers, the rollers will grip the tablet and pull it downward with considerably less crushing of the edges of the tablet than occurs when the spacing between the central portions is substantially the same as the spacing between the end portions.

ln the embodiment shown in Fig. 4, this variation in spacing is achieved by dividing the surface of each of the rollers into laxially disposed Zones, the roller 52 having an end zone 77, a central zone 78 and an end zone 79 and the rollervSl having an end Zone Sil,- a central zone 8l and an end Zone 82. The width of the space between the corresponding end zones '77, 80 and 79, 82. is made slightly greater than the thickness of the tablet, being in the order ofV a few thousandths of an inch greater. When the space between the central Zones '78, 81 is Amade slightly greater than the spaces between the end Zones, crushing of the edges of the tablet is substantially eliminated. For example, using a tablet which is three sixteenths of an inch thick, an increase in width of the central space over the end spaces in the order of two to live thousandths of an inch will provide the desired breaking action, the central spacing preferably being about three thousandths of an inch greater. The axial length of the working surfaces of the rollers is made approximately equal to the diameter of the tablet to be dispensed, as seen in Fig. 4, where a tablet is shown in phantom between the rollers. lt is preferred to make the three zones approximately equal in axial length since optimum operation is achieved with this arrangement.

A preferred form for the concave and convex surfaces of the rollers is shown in Fig. 4, this form being easy to manufacture and producing excellent results in fracturing tablets without crushing. The lines of intersection of each of the surfaces with a plane passing through the axes of the rollers are arcs of circles, the line formed by the opposing end zones having common radii, the lines formed by the central zone 81 of the roller 5i having radii slightly greater than the corresponding common radii and the radii of the arcs formed by the central portion 78 of the roller 52 being slightly less than the corresponding common radii. The differences in length referred to in the previous sentence are quite small and desirable results are obtained when such differences are in the order of two percent of the length of a radius.

lt has been found that adhesion of dust and small particles from the tablet to the surfaces of the rollers may be substantially reduced by providing the surfaces with a roughed finish. The rollers are made of metal or similar hardmaterial with a smooth surface finish. Then the surfaces are treated to produce a large quantity of shallow grooves or depressions in the order of a few tenthousandths of an inch deep, the grooves or depressions being relatively smooth.

In one form of the invention shown in Figs. 3 and 4, a large number of smooth, shallow depressions are made in the surfaces of the rollers, preferably substantially covering Athe surfaces. These smooth, shallow depressions may be made by any suitable method, such as by peening, shot blasting or the like. The depth of such depressions is quite critical to the proper operation of the invention. The depressions should not be more than one thousandth of an inch in maximum depth and preferably should `be inthe range of two to live ten-thousandths of an inch in maximum depth. If the depressions are less than two ten-thousandths, there is little or no improvement over the performance of the smooth surfaced rollers previously used. If the depressions are more than one thousandth deep, they tend to lill with caked dust and no advantage is gained from their presence. However, when the `depressions are provided in the range indicated, there is very little adhesion of dust and small particles of the tablets to the surface of the rollers, the rollers remaining cleaner than if the conventional scrapers were being utilized.

In an alternative form of the invention, the rollers are roughed by forming shallow grooves in the surfaces thereof, the grooves preferably extending in an axial direction. This form is illustrated in Fig. 6, wherein grooves 85, 86 are shown highly exaggerated. The grooves may be produced by various suitable methods, lsuch as by lightly builing the surfaces with about No. 80 emery paper. As indicated above, the resultant grooves should be shallow, preferably in the range of two to five tenthousandths of an inch.

The objects of the invention are thus achieved by providing the rollers in a tablet breaker and dispenser with the new features described herein. A tablet of the type handled in the dispenser described herein is` shown in Fig. 5a and a reconstructed fractured tablet is shown in Fig. 5b illustrating the type of segments produced by the rollersl of the invention.

Although an exemplary embodiment of the invention has been disclosed and discussed, it will be understood that other applications of the invention are possible and that the embodiments disclosed may be subjected to various changes, modifications and substitutions without necessarily departing from the spirit of the invention.

I claim as my invention:

1. A pair of spaced rollers for use in a tablet breaker and dispenser having means for feeding tablets to the space between said rollers and means for counterrotating said rollers with the adjacent surfaces of said rollers moving in a downward direction away from such tablets, one of said rollers having a concave surface of revolution and the other of said roller having a convex surface of revolution, each of said surfaces being divided into three axially spaced zones providing a central zone and a pair of end zones on each surface, with the lines of intersection of each of said pairs of end zones with a plane passing through the axes of said rollers lying in smooth curves, the line of intersection in each of said central zones with said plane being between the corresponding smooth curve and axis,`with the surface of each of said rollers having Ia plurality of shallow depressions therein.

2. A pair of spaced rollers for use in a tablet breaker and dispenser having means for feeding tablets to the space between said rollers and means for counteirotating said rollers with the adjacent surfaces of said rollers moving in a downward direction away from such tablets, one of said rollers having a concave surface of revolution and the other of said rollers having a convex surface of revolution, the distance between said surfaces being at least as great as the thickness of the tablet being dispensed, each of said surfaces being divided into three axially spaced zones providing a central zone and a pair of end zones on each surface, with the lines of intersection of each of said pairs of end zones with a plane passing through the axes of said roller lying in smooth curves, the lines of intersection of each of said central zones with said plane being spaced from the corresponding smooth curve towards the corresponding axis a distance that is small relative to the thickness of the tablet i being dispensed, with the surface of each of said rollers having a plurality of shallow depressions therein.

3. A pair of spaced rollers for use in a tablet breaker and dispenser having means for feeding tablets to the space between said rollers and means for counterrotating the rollers with the adjacent surfaces of said rollers moving in a downward direction away from such tablets, one of said rollers having a concave surface of revolution and the other of said rollers having a convex surface of revolution, with each of said surfaces having a plurality of shallow depressions therein, the distance between said surfaces being at least as great as the thickness'of the tablet being dispensed, the distance between said surfaces at the middle thereof being greater than the distance between said surfaces at each end thereof.

4. A pair of spaced rollers for use in a tablet breaker and dispenser having means for feeding tablets of a particular thickness to the space between said rollers and means for counterrotating the rollers with the adjacent surfaces of said rollers moving in a downward direction away from such tablets, one of said rollers having a concave surface of revolution and the other of said rollers having a convex surface of revolution, with each of said surfaces having a plurality of shallow depressions therein, the distance between said surfaces being at least as great as the thickness of the tablet being d1spe.nsed.

5. A pair of rollers as defined in claim 4 in which said depressions are not more than one thousandth of an inch a n n u 6. A pair of rollers as defined in claim 4 in which said depressions are round and have a maximum depth of not less than two and not more than tive ten-thousandths of an inch.

7. A pair of rollers as defined in claim 4 in which said depressions vare grooves extending in a generally axial CTI t 6 direction along the surfaces of the rollers, said grooves being not more than one thousandth of an inch deep.

8. A pair of spaced rollers for use in a tablet breaker and dispenser `having means for feeding tablets to the space between saidrollers and means for counterrotating the rollers with the adjacent surfaces of said rollers moving in a downward direction away from such tablets, one of said rollers having a concave surface of revolution and the other of said rollers having a convex surface l of revolution, the distance between said surfaces being at least as great as the thickness of the tablet being dispensed, the distance between said surfaces at the iniddle thereof being greater than the distance between said surfaces at each end thereof.

9. A pair of spaced rollers for use in a tablet breaker and dispenser having means for feeding tablets to the space between said rollers and means for counterrotating said rollers with the adjacent surfaces of said rollers moving in a downward direction away from such tablets, one of said rollers having a concave surface of revolution and the other of said rollers having a convex surface of revolution, each of said surfaces being divided into three axially spaced zones providing a central zone and a pair of end zones on each surface, with the lines of intersection of each of said pairs of end zones with a plane passing through the axes of said rollers lying in smooth curves, the line of intersection of each of said central zones with said plane being between the corresponding smooth curve and axis.

l0. A pair of rollers as defined in claim 9.in which the axial length of each of said rollers is substantially equal to the diameter of the tablet being dispensed and in which the three zones of each of said rollers are substantially equal in axial length.

l1. A pair of spaced rollers for use in a tablet breaker and dispenser having means for feeding tablets to the space between said rollers and means for counterrotating said rollers with the adjacent surfaces of said rollers moving in a downward direction away from such tablets, one of said rollers having a concave surface of revolution and the other of said rollers having a convex surface of revolution, the distance between said surfaces being at least as great as the thickness of the tablet being dispensed, each of said surfaces being divided into three axially spaced zones providing a central zone and a pair of end zones on each surface, with the lines of intersection of each of said pairs of end zones with a plane passing through the axes of said rollers lying in smooth curves, the lines of intersection of each of said central zones with said plane being spaced from the corresponding smooth curve towards the corresponding axis a distance that is small relative to the thickness of the tablet being dispensed.

12. A pair of spaced rollers for use in a tablet breaker and dispenser having means for feeding tablets to the space between said rollers and means for counterrotating said rollers with the adjacent surfaces of said rollers moving in a downward direction away from such tablets, one of said rollers having a concave surface of revolution divided into axial zones including a central zone and a pair of opposing end zones, the surfaces of said end zones having a common radius, the surface of said central zone having a radius in the order of two percent greater than said common radius, the other of said rollers having a convex surface of revolution divided into axial zones including a central zone and a pair of opposing end zones, the surfaces of said end zones having a common radius, the surface of said central zone having a radius of two percent less than said common radius.

References Cited in the file of this patent UNITED STATES PATENTS 294,361 Bowers Mar. 4, 1884 1,743,623 Ross Ian. 14, 1930 2,100,860 Lobley Nov. 30, 1937

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