US2928172A - Apparatus for dividing by volume plastic materials - Google Patents

Description

March 15, 1960 2,928,172

APPARATUS FOR DIVIDING BY VOLUME PLASTIC MATERIALS Filed June 4, 195'? -r. L. A. M. STEENHUIS 2 Sheets-Sheet 1 INVENTOR THEODOR LUDWIG AUGUST MARIA STEENHUIS BY 1 B a HIS ATTORNEYS March 15, 1960 T. 1.. A. M. STEENHUIS 2 APPARATUS FOR nxvmmc; BY VOLUME PLASTIC MATERIALS Filed June 4, 1957 2 Sheets-Sheet 2 Flea. I 29 lNVENTOR THEODOR LUDWIG AUGUST MARIA STEENHUIS BY 5 I HISYATTORNEYS iinited States Patent APPARATUS FOR DIVIDING BY VOLUME PLASTIC MATERIALS Theodor Ludwig August Maria Steenhuis, Kleve, Ger-- many, assiguor to Lever Brothers Company, New York,

channel member having an internal piston movable at right angles to the direction of rotation.

in the processing of plastic substances such as marga rine, for example, volume measuring devices have been utilized comprised of a channel member rotatably mounted between diametrically opposed inlet and outlet chambers and a piston within the channel movable at right angles to the axis of its rotation. Such a device, as

shown in Us. Patent No. 2,683,932'for example, receives a measured quantity of material from the inlet chamber when the piston is moved away fromthat chamber and, after the channel member rotates half a revolution, ejects the measured quantity into the exit chamber while drawing in another quantity of material by a similar motion of the piston.

In the various known devices of this type, the successive measured quantities form a continuous bar in the outlet chamber. After every piston stroke a quantity is severed from this bar for packaging, but the surface severed does not coincide with the interface between the successive measured quantities and, therefore, each of the severed units contains a planar discontinuity which may cause the unit to break easily. Further, in the known devices, the channel member must be rotated rapidly through a half revolution and then stopped abruptly while the measuring piston makes it stroke. The extreme forces exerted on the mechanism by this operation greatly promote wear and breakage and limit the operating speed of the apparatus.

Accordingly, it is an object of this invention to provide apparatus of the above character wherein the separation between the successive measured quantities of material is less abrupt and extends partially in a longitudinal direction so that the severed unit is less likely to break.

Another object of the invention is to provide apparatus of the above character wherein the channel member and its associated piston are each accelerated and decelerated smoothly and uniformly so that a higher operating speed is attainable and wear and breakage of the mechanism are substantially reduced.

These and other objects of the invention are accomplished by providing relative motion between the channel and the outlet chamber while the piston is moved to eject the measured quantity of material. More particularly, the channel member is rotated continuously with a sinusoidal motion having velocity minima-when the channel is aligned with the inlet and outlet chamber openings and the piston is driven in a similar manner but with a velocity which increases as the overlapping of the channel and outlet chamber opening increases and decreases as this overlapping is reduced.

In one embodiment of the invention, the channel member drive mechanism includes a constantly rotating slotted crank arm engaging a pin mounted near the periphery of an eccentrically supported gear member while the ,n 2,928,172 Patented Man-.15, 1960 ice ' piston member is actuated in the desired manner from a member drive mechanism.

Further objects and advantages ofthe invention will be apparent from a reading of the following description taken in conjunction with the accompanying drawings in which:

Fig. i is a side elevation showing a typical volume di= viding apparatus arranged according to the invention;

Fig. 2 is a plan view of the apparatus drive mechanism taken along the lines 2-2 of Fig. 1;

Fig. 3 is an enlarged fragmentary view partly "in section of the drive mechanism shown in Fig. 2; and

Fig. 4 is an enlarged side elevation of'the portion of the mechanism shown in Fig. 3, taken along the lines ia-4 of Fig. 2 and looking in the direction of the arrows.

Referring to Figs. 1 and 2, the apparatus comprises a casing 1 forming a volume divider having a rotatably mounted internal channel member 1a with a piston 1b movable within the channel and provided with an inlet chamber 2 and an outlet chamber 3 with which the channel may communicate and to which conventional mate- [rial supplying and discharge devices (not shown) may be connected. Associated'with the outlet chamber is a conventionai cutting mechanism (not shown) which may be actuated by means ofa bar 4, a crank arm pivotally.

mounted in a journal 5, and a lever pivotally mounted at d which is actuated by a cam 7 'mounted on an axle 8. The axle 8 is driven by two bevel gears 9 and 10 and two axles 11 and 12 on which two engaging gear wheels 13 and Mare mounted, respectively. A constantly rotating shaft 1'] drives, the axle 12 through 'a Worm wheel 15 and a worm 16, the shaft 17 being powered from any suitable motive source.

The interior structure of the channel member 1a and the piston 1b is not shown in detail, being of the usual design, for example as shown in US. Patent, No. 2,683,- 932, wherein the piston is operated through an external member such as a lever 23 which is pivotally mounted on a journal 22. 'In order to actuate the piston 1b in conjunction with the rotation. of the internal channel member in, a cam 18 mounted on the constantly rotating axle 12 drives a lever 19 fixed at one end in a journal 20 and linked at the other end 'to the lever 23 through a bar 21.

-Rotation of the channel member 1a is accomplished through th'e bevel gears 25 and 26 which are connected to the channel member and to an axle 27 respectively. The axle 27 is driven by two bevel gears 28 and 30 and another axle 29 on whichthe gear 30 is mounted. Another axle 31 is driven from the constantly rotating shaft 17 through a worm wheel 42 aflixed to the axle and a worm 43 mounted on the shaft.

The linkage between the axle 29 and the axle 31 converts the constant rotation of the input shaft 17 to a sinusoidal velocity rotation, which is transmitted to the channel member 1a through the axles 27 and 29. to produce this motion, the axle 31 carries a crank arm 38 keyed thereto by a pin 37 and having a radial slot 39, as best seen in Figs. 3 and 4. Surrounding the axle 31, a gear 33 is eccentrically supported in a cylinder 34 which is affixed to a portion of the frame 36, the axle 31 being supported in a journal 35 afiixed to the frame. Near the periphery of the gear 33 a pin 40 is mounted and a roller 41 supported on the pin engages the slot 39 of the crank arm. Another gear 32 engages the teeth of the gear 33 and transmits motion therefrom to the axle 29.

In operation, it will be readily observed that rotation of the arm 38 at constant velocity produces the desired sinusoidal velocity of the gear 33 because of the eccen- In order tricity "e between the gear center and the axle 31. When the arm 38 is in the position shown in Fig. 4, maximum rotational velocity is imparted thereby to the gear 33 and when these parts are in the diametrically opposite position, the gear 33 rotates with minimum velocity but in the same direction. By interposing a gear reduction of two to one at the gears 25 and 26, for example, and by proper timing of these gears, the channel 1a may be rotated with a minimum velocity occurring twice during each revolution, when the channel is aligned with the openings to the chambers 2 and 3, and a maximum velocity at two intermediate positions.

The operation of the piston 1b through the lever 23 is timed according to the position of the cam 18 on the axle 12 and this is preferably arranged to produce maximum piston velocity at the times when the channel is aligned with theopenings to the chambers 2 and 3. The shape of the cam 18 determines the duration of the piston stroke which preferably begins when the channel and the opening to the outlet chamber 3 begin to overlap and ends when the overlapping terminates. Inasmuch as the axle 12 rotates synchronously with the axle 31, the piston 11; performs two strokes for each revolution of the channel member 1a. The above-described relative motion between the channel member 1a and the opening to the outlet chamber 3 while the piston makes its stroke results in a curved interface between successive measured quantities of material in the chamber 3 and promotes mixing of the material along the interface. By a similartiming arrangement of the cam 7, the cutter driven by the bar 4 is actuated twice during each revolution of the channel member 1a at times when the channel is not in communication with the opening to the outlet chamber Although the invention has been described with reference to a specific embodiment, many variations and modificationsthereof will occur to those skilled in the art. Accordingly, the scope of the invention is not intended to be limited except as defined by the following claims. i i i I claim:

1. Apparatus for delivering exact volumes of plastic materials comprising a casing forming a volume divider having an inlet chamber and an outlet chamber diametrically opposed to the inlet chamber, an internal chan nel member mounted within the casing rotatable about an axis substantially perpendicular to the casing diameter joining the inlet and outlet chambers and having a channel communicable with both the inlet and outlet chambers, a piston mounted within the channel member and reciprocable therein, drive means operatively associated with the channel member and the piston, varying velocity means within the drive means linked with the channel member for continuously rotating it with varying velocity, and

means within the drive means connected to the piston for actuating the piston in timed relation to the rotation of the channel member.

2. Apparatus according to claim 1 wherein the varying velocity means includes means for transmitting motion to the channel member with a sinusoidally varying velocity which has a minimum value when the channel is aligned with the inlet and outlet chambers.

3. Apparatus according to claim 2 wherein the rotating means comprises an axle rotating with constant velocity, radial slot means associated with the axle, a gear supported eccentrically with respect to the axle, and slot engaging means mounted on the gear and cooperating with the radial slot means to rotate the gear with a sinusoidally varying velocity.

4. Apparatus according to claim 1 wherein the means for actuating the piston comprises constantly rotating cam means and lever means operated by the cam means to actuate a piston drive lever with varying velocity.

5. Apparatus according to claim 1 wherein the means for actuating the piston comprises means for imparting a motion to the piston having maximum. velocity when the channel in the channel member is aligned with the inlet and outlet chambers.

6. Apparatus according to claim 1 wherein means for actuating the piston comprises means for starting the piston motion when the channel starts to overlap the outlet chamber.

7. Apparatus according to claim 1 wherein the means for actuating the piston comprises means for terminating the piston motion when the overlapping of the channel and the outlet chamber terminates.

8. Apparatus according to claim 1 including cutting means for separating measured quantities of material from the outlet chamber at a point spaced from the channel member and means for actuating the cutting means in timed relation to the rotation of the channel member.

9. Apparatus according to claim 8 wherein the means for actuating the cutting means comprises a constantly rotating cam and a lever operated thereby.

10. Apparatus according to claim 8 wherein the actuating means includes means for operating the cutting means when the channel is at a position other than one communicating with the outlet chamber.

References Cited in the file of this patent UNITED STATES PATENTS

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