US2657582A

US2657582A - Mechanism for producing gyratory motion

Info

Publication number: US2657582A
Application number: US186958A
Authority: US
Inventors: William C Conkling
Original assignee: Richmond Manufacturing Co
Current assignee: Richmond Manufacturing Co
Priority date: 1950-09-27
Filing date: 1950-09-27
Publication date: 1953-11-03
Anticipated expiration: 1970-11-03

Description

Nov. 3, 1953 w. c. CONKLING 2,657,582

MECHANISM FOR PRODUCING GYRATORY MOTION Filed Sept. 27. 1950 2 Sheets-Shet 1 INVEN TOR.

ATTU/m/[Xi Nov. 3, 1953 w. c. CONKLING 2,657,582

MECHANISM FOR PRODUCING GYRATORY MOTION Filed Sept. 27, 1950 2 Sheets-Sheet 2 INVENTOR.

ATTORNEYS.

Patented Nov. 3, 1953 UNITED' STATES PATENT OFFICE MECHANISM FOR PRODUCING GYRATORY MOTIO William 0. Conkling, Lockport, N. Y., assignor to Richmond Manufacturing Company, Lockport, N. Y., a corporation of New York Application September 27, 1950, Serial No. 186,958

9 Claims.

to provide an extremely simple and low cost eccentric weight type of mechanism for producing gyratory motion which on starting produces small circles of gyration which increase in size until running speed is reached when circles of the desired amplitude are produced and which on stopping progressively decreases the amplitude of the circles until the mechanism comes to rest. 7

Another object is to achieve such action on starting and stopping as a function of gravity thereby to avoid sliding parts and return springs which are subject to fouling with flour dust.

Another object is to provide such a mechanism which is conveniently adjustable to produce circles of different sizes at running speed.

-Another object is to provide such a mechanism which is fully cushioned, particularly on starting and stopping, and is free from destructive escaping vibrations while running, starting or stopping.

Another object is to provide such a mechanism which is adaptable to large sifters carrying heavy loads and to the space requirements imposed on such sifters.

Another object is to provide such a mechanism which can be driven from a motor on the sifter, from a belt running to the sifter or from a direct drive shaft above or below the sifter.

Another object is to provide such a mechanism which is simple and inexpensive in construction, reliable in operation, and which will stand up under conditions of severe and constant use without getting out of order or requiring repairs.

'Another object is to provide such a mechanism which is free from friction.

Other objects and advantages of the invention will be apparent from the following description and drawings in which Fig. 1 is a side elevational view of a mechanism embodying the present invention forv gyrating a sifter, a part of the frame of which is illustrated. The mechanism is shown in its static state.

Fig. 2 is a horizontal section taken generally on line 2-4, Fig. 3.

One of the principal objects of the invention is Fig. 3 is a vertical longitudinal section taken generally on line 3-3, Fig. 2.

The mechanism embodying the present invention for producing gyratory motion in a horizontal plane is shown as comprising a vertical shaft l0 suitably journalled at its upper and lower ends in bearings II and I2 one or both of which can be thrust bearings to support the shaft. The upper bearing II is shown as being part of an upper spider I3 and the lower bearing I2 is shown as being part of a lower spider l4. These spiders can form part of the central frame structure of a high speed gyratory sifter, but since this frame structure forms no part of the present invention it is not illustrated in further detail.

The vertical shaft I!) can be rotated in any suitable manner and for this purpose can be provided at its top or bottom with a projecting end I 5. This projecting end can be driven by an electric motor (not shown) mounted on the spider l3; a belt and pulley drive (not shown); or a vertical drive shaft (not shown) having a universal and directly connected with the shaft end 5.

Between the bearings H and I2 the vertical shaft ID carries a pair of spaced rectangular blocks 18 the vertical faces of which are parallel with the axis of the shaft l0 and these blocks being preferably secured to the shaft I 0 by set screw l9. Each block [8 also has a pair of pins 20 projecting horizontally from opposite sides thereof, the four pins 20 being parallel and in vertical alinement with each other. A roller 2| is journalled on each of these pins, preferably by roller bearings to reduce friction, and each roller is preferably radially flanged, as indicated at 22, on one side.

The blocks l8 are flanked by vertical plates 23 each having a vertical flange 24 along the vertical edge nearest the shaft It! when the mechanism is at rest as shown in the drawings. These vertical flanges 24 project outwardly or away from each other and are secured together by a vertical gang of weights 25. The purpose of the flanges 22 of the rollers 2| is to restrain the plate and weight assembly from cocking and to space the plates 23 from the blocks 18. These weights are preferably made of roughly cast non of C-shaped form in horizontal section each being idented, indicated at 26, so that the corresponding weights fit around the blocks [8, and each weight being secured to the flanges 24 by screws 28. As shown, these weights 25 are in a vertical gang, a column of four weights being shown. It will therefore be seen that this gan of weights 25 is, in effect, a vertically elongated weight.

Each plate 23 is provided with upper and lower arcuate slots 29 which are arranged to receive the rollers 2| and which curve downwardly away from thever'tical shaft [8. Tr1 e'-tipter-5ewerk ing edge of each of the upper slots" has welded thereto an arcuate hardened rail 30. Each of the lower slots 29 also has welded thereto arr arcuate hardened rail 3|. The reason for the arrangement of the hardened rails" 33 along the} top edges of the upper arcuate slots 29 and of the hardened rails 3| alongtlie: lower eageeesthe lower arcuate slots 29 is tllettthe gang off weights tend to tip in a corresponding direction and hence establish these rails as the working surfaces.

Each plate 23 is also provided with an upper and a lower series of holes 32 extending toward the shaft l, eachhole of the upper series being preferably in vertical alinement with-a cone-- spending hole of the lo'vi'rer' series and the holes of the two plates 23 alining horizontally with one another. The series of holes 3Z1are preferably;

but not necessarily-arranged at an angle incli'ne'd to conform tothe arcu'ate' slots 29.

A: removable" pin 33 extends through a corresponding: pair of the upper series of holes 32 in thetwo plates 23 andcanj be moved to extend through any pairof these holes thereby to adjl'istthe position or this pin with reference td the gang ofweights For this purpose the pin 33"is prefera-bly in the form of a bolt having a head 34 at one end and anut 35 at it's'oppo'site end so that it can readily be pulled out from one pair ofthe-two upper'series of holes 32- and replaced in another" or these pairs of holes;

This pin 33 carries; bet-ween the plates 23,- a square block 36 to one face of which the upper end or a leaf spring 38 is secured; This leaf spring; hangs from this block and preferably arches toward the vertical shaft f'll. At its lower end this spring bears against aroller' 396151 a pin 40 extending through a correspondinghole 32 of the-"lower series of' th'e'se holes; pin

la-is also replaceable in any pair of holes 3 2 of" the lower series in the two plates 23 andhence is preferably'ir'r the formof abolt having a head 4| atone end and: a nut at its oppositeend so that it can be readily pulled out from one pair erthe two lower series of holes 32 and replace another or these pair wholes:

Secured, asby bolts 43, to the center of the leaf spring '38 is a; second vertically'arrangd arched leafv spring 44- which;- However; bows oppositely to the'leaf spring 33 so that its ends project to ward the gang of weights 2 5. This l'astarched leaf spring 44" is preferably faced Wltllleather 45 and its ends are arranged toengage the meme The mechanism is particularly designed rotehigh speed gyrat'dry sifter t6 be driven at from;-

say; 180' to 300' revolutions per minute with from say,- 2 to 4 inch circles; With the sifterhavingj say, a natural frequency or 30revclut-ions or pendulum' like gyrations per minute; determined by the effectivelhgth- 0f the flexible suspension-,

until the sifter gets te gyrate' abeve this naturalfrequency p'erfectcircle's are impossible since natural-frequency may be carrying-the sifter' frame in one direction and the weights 25 same direction with ado'iible'd unbalancing' force; 1

Accordingly before ar a after the s'i-fter is run: ning at full speed it is desirable that it describe trircgarreree acting on the weights 25 causes 4 smaller circles since otherwise there would be excessive escaping vibrations due to the fact that the circles are not perfect,

To accomplish this the center of gravity of the gang of weights 25 is initially arranged near the axis of the vertical shaft Ill which preferably iaterseets center of gravity: of the' Sifter. It w-i-lr-te under-steed; however, tfiatthe center of gravity of the gang of weights must initially be slightly on the side of the axis of the shaft ll remote-from the

leaf springs

33 and 44. Accordingly as this "shaft starts to rotate the weights have relatively small efiect in gyrating the erdescribes relatively small cir- Asthhalf't' Hl picks up in speed the centhem' to move' radially outwardly, the rollers 2| riding down the hardened

rails

30 and 3| and hence-the weights also rising vertically, In this action the gang of weights 25 have a tendency totip and hence-the hardened rail 30 is disposed along the topof its slot 29 while the hardened rail" 3| is disposed along the bottomof its slot 2-9;

As the shaft M" reaches its maximum speed the rollers 21' approach close to the bottoms of the 'arcuate' slots 29 and'the ends of the leather faced leaf spring" mt. engage the blocks |8. This causes this spring and lts supporting leaf spring 38*to' flatten 0111; against the pins 33 and 40', these springs thereby serving as a resilient stop to the outward move ment of the gang of weights 25. The springs 38 act as positive stops which prevent complete bot:

toming of the rollers 21 in the bottoms of the slots 29'. The resiliency provided by these leaf springsprevents jarring or the sifter as it is brought" under control to describe running circles of the desired amplitude;

The size of these running circles ofgyration can easily be'adju'ste'cl. 'ThlllS th' Sifter is $817" to gyrate with circleso'f maximum" amplitude. If smaller circles are desired, the

bolts

33 and 40 are removed and replaced in the next higher closer to these weights and hence" these weights are stopped closer to the axis of'the" shaft to this shaft reaches full running speed circles; at running speed, of smaller amplitude result;

It will particularly be noted that these

bolts

33 and 40 are readily replaced to secure the dc sired circular orbit of the sifter. There is no need to jack up the-weights 25 or to undertake anycther difficult work.

When the driving force is relieved from the vertical shaft l0 it gradually slows down and" sincedecr-easing centrifu al force is app'li'edto the weights 25 they gradually lower by gravity the' rollers- 21 riding up the arcuate" slots 2-9 and the gang of weights-coming closer to the axis of? the'shaf-t m as the sitter comes to rest; Accord: ingly as the rate of gyration of the Sifter falls below the natural frequency thereof the size of. the circles generated. is" sfnall and the" unbalance of the forces do not set up a pronounced walkingv or cradling action of thesifte'r;

In the action of the sifter, the shape of the arcrxateslots 29 is important. Thus, it will be noted that" the slope of the rails of each of" these' slots increases tdwa'rd its lower end.

cordingly as a result of the action of the inclined rails on the rollers there is a restraining horizontal force to the movement of the gang of weights 25 which increases-with the movement of the weights from: the axis of the shaft If). This is desirable as the centrifugal force of the gang of weights is proportional to the length of the radius from the center of the shaft 18 to the center of gravity of the weights 25. Accordingly it is desirable that the horizontal component due to the action of the rollers in the slots 29 increases at a greater rate than this radius so that there is no tendency for a sudden outwardmovement of the weights due to the increase in centrifugal force as they move outwardly. Expressed in another way, the form of the rails of the arcuate slots 29 is such that the horizontal force opposing movement of the weight 25 away from the shaft I9 increases at a greater rate than the centrifugal force of the weight increases.

From the foregoing it will be seen that the present invention provides an extremely simple and low cost mechanism for gyrating heavy sifters and the like which is easily adjustable to produce different amplitudes of gyration at running speed, is free from tendency to foul, and accomplishes the many objects enumerated.

I claim:

1. A mechanism for producing gyratory motion, comprising a vertical shaft, a pair of vertical plates flanking said shaft, a vertically elongated weight connecting said plates and arranged adjacent said shaft in the static condition of the mechanism, means for guiding said plates to cause an upward movement of said weight away from said shaft, and a stop interposed between said plates on the side of said shaft opposite from said weight and arranged to limit the horizontal movement of said weight away from said shaft.

2. A mechanism for producing gyratory motion, comprising a vertical shaft, a pair of vertical plates flanking said shaft, a vertically elongated weight connecting said plates and arranged adjacent said shaft in the static condition of the mechanism, means for guiding said plates to cause an upward movement of said weight away from said shaft, and a stop resiliently mounted on said plates and interposed therebetween and coacting with said shaft to limit the horizontal movement of said weight away from said shaft.

3. A mechanism for producing gyratory motion, comprising a vertical shaft, a pair of vertical plates flanking said shaft, a vertically elongated weight connecting said plates and arranged adjacent said shaft in the static condition of the mechanism, means for guiding said plates to cause an upward movement of said weight away from said shaft, a stop interposed between said plates on the side of said shaft opposite from said weight and arranged to limit the horizontal movement of said weight away from said shaft, and means for shifting said stop horizontally along said plates toward and from said weight.

4. A mechanism for producing gyratory motion, comprising a vertical shaft, a pair of vertical plates flanking said shaft, a vertically elongated weight connecting said plates and arranged adjacent said shaft in the static condition of the mechanism, means for guiding said plates to cause an upward movement of said weight away from said shaft, a stop resiliently mounted on said plates and interposed therebetween and coacting with said shaft to limit the horizontal movement of said weight away from said shaft, and means for shifting said stop horizontally along said plates toward and from said weight.

5. A mechanism for producing gyratory motion, comprising a vertical shaft, a pair of vertical plates flanking said shaft, a vertically elongated weight connecting said plates and arranged adjacent said shaft in the static condition of the mechanism, means for guiding said plates to cause an upward movement of said weight away from said shaft, a cross bolt insertable through registering holes through said plates of a series of holes extending horizontally toward said shaft from the side thereof opposite said weight, and

a stop on said cross bolt between said plates and,

coacting with said shaft to limit the horizontal movement of said weight away from said shaft.

6. A mechanism for producing gyratory motion, comprising a vertical shaft, a pair of vertical plates flanking said shaft, a vertically elongated weight connecting said plates and arranged adjacent said shaft in the static condition of the mechanism, means for guiding said plates to cause an upward movement of said weight away from said shaft, comprising a pair of vertically spaced blocks fast to said shaft, a pair of coaxial rollers projecting in opposite directions from each of said blocks with their axes arranged perpendicularly to said plates and each roller riding in an inclined guideway provided in the adjacent part of the corresponding plate, said guideways being generally parallel with one another, a pair of resilient stops interposed between said plates on the side of said shaft opposite from said weight and each arranged to engage a corresponding one of said blocks to limit the horizontal movement of said weight away from said shaft, and means for shifting each of said stops horizontally along said plates toward and from said weight.

7. A mechanism for producing gyratory motion, comprising a vertical shaft, a pair of vertical plates flanking said shaft, a vertically elongated weight connecting said plates and arranged adjacent said shaft in the static condition of the mechanism, means for guiding said plates to cause an upward movement of said Weight away from said shaft, comprising a pair of vertically spaced blocks fast to said shaft, a pair of coaxial rollers projecting in opposite directions from each of said blocks with their axes arranged perpendicularly to said plates and each roller riding in an inclined guideway provided in the adjacent part of the corresponding plate, said guideways being generally parallel with one another, a leaf spring interposed between said plates on the side of said shaft opposite from said weight and having its opposite ends arranged to engage said blocks to limit the horizontal movement of said weight away from said shaft, and means for shifting said leaf spring horizontally along said plates toward and from said Weight.

8. A mechanism for producing gyratory motion, comprising a vertical shaft, a pair of vertical plates flanking said shaft, a vertically elongated weight connecting said plates and arranged adjacent said shaft in the static condition of the mechanism, means for guiding said plates to cause an upward movement of said weight away from said shaft, comprising a pair of vertically spaced blocks fast to said shaft, a pair of coaxial rollers projecting in opposite directions from each of said blocks with their axes arranged perpendicularly to said plates and each roller riding in an inclined guideway provided in the adjacent 7 part of the correspondin plate, said guideways being generally parallel with one another, a vertical leaf spring interposed between said plates am the side: (if. mm; dppm'site; 1mm. said wefgm, a, 2mm seua ing' cm'e eimefsaid l'eaiflspfingi t6 5am platefi and ins-mama regi stexmg pairs. 0 h0Ie= tmrcxugri smich 'lxes of. a1 sefisszextnmg hz izbntal'ly'towrdl saixfl shsalft, whacking baht engagin me rather em of saiei leaf spring: max-table in lfgisfi'ringf pairs 0:? moles thrcm'gh: sa'i dplfies of a series extending homronml ly rim midi'sa id shaftana'a: semndi-li safisprin seamed at;- i deiiiiral pwrt; ad the Gamma part; at san d firsi; spring, the: ends oi saiki s'eeond Ieaif sptii ig Being n-g zigeasbl; with said blo iks w limit jhe duffiweimi-moverhnfiof sai'd weignt relative to said Sm lavfifiany as a unitary structure transversely of mvemept of s'aiid wigm away from saidlshaft 2,516,207

ix'imwszsessv at a" gzwterur ste; i centnifizgnk farce increases, comprising a. guide: slbl' and roller plates and saidshaflz, m-laasecandguide sIot on Sam. guide si ots, me Siam condifian of um mechanism, being" disposed on the side ofisadd shaft'hopiwsite fimm-said one side-thereof;

WILLIAM C; CONKLING,.

R fimw sfii ed; h le 1' his nt WEED S TES PA' EN' Name Date Climbs Jun-e a; 1 915 Number its l'ower end arrangedremote; imm- Heberbrand- June 4, was: Hartwi'g July 25;, W