US1984302A - Time period control device - Google Patents

Description

R. P. DE vRls TIME PERIOD CONTROL DEVICE .Filed July 51, l93l 4Sheets-Sheet 1 'I I z.

Dec.'11, 1934. R. P. DE VRIES TIME PERIOD CONTROL DEVICE Filed July 31, 1931 4 Sheets-Sheet 2 INVENTOR 5m MN m w @QMN NN "N F fink 5m N NQ NQN N NM aw H J. -F -T I .i l NWN. g ugh-w Q E "Q 4 Q N awn P x -H i un m. x L f m 1mm" a gNwx "N 5R. EY E M r. M 1 m w .3: AM a J o 1 a I 8 w b X M m 2 .w. a 1 W 1 LU" V1.41 g

Dec. 1 l, '1934.

Dec. 11, 1934.

R. P. DE VRIES TIME PERIOD CONTROL DEVICE Filed July 51, 1931 4 Shee'ts-.-Sheet 1 4 Patented use. 11, 1934 UNITED STATES 'PATENT' OFFICE Application July 31, 19:1, sci-mm. 554,269

the time periods in a cycle of operation and particularly to' a device adapted for use with sugar purifying centrifugals to control the duration of certain steps in the refining process.

Centrifugal machines are quite commonly employed in various stages of .the sugar refining process. In the use of these machines the first operation consists in starting the porous basket rotating and introducing the proper amount of sugar magma. The basket continues to rotate during the first so-called purging period during which a large portion of the mother liquor is thrown out through the pores of the basket and is conducted away. effect of walling up the sugar against the inner surface of the basket and when a large portion of the mother liquor has left the sugar, a spray of water is turned on against this inner walled surface to remove whatever liquor may still remain adhering to the crystals. At the completion of this spraying period the water is turned off. and the basket continues to rotate during the drying period for the purpose of removing the excess water. At the proper time thereafter the power is shut off and brakes are applied to bring the basket to a stop after which the purified sugar is removed.

It is highly essential for efliciency of operation and uniformity of product that the various time intervals of this process be correct and unvarying for a .given consistency of sugar magma. Thus if the purging period is too long, the sugar will commence to harden against the walls of the basket with obvious harmful results, or, if too short, the liquor will not be sufliciently removed and an excess amount of spray water will be required for a pure product. An unduly long spraying time must always be avoided, to prevent dissolving of the sugar. For efflcient centrifugal operation not only must the steps in the cycle be uniform but it is equally important that there be some way of changing these various time periods to correspond with the fluctuations in the -consistency of the sugar magma as 1 different batches are introduced.

It has been recognized in the prior art that the control of these time periods should not be left to the judgment of the operative and a number of devices have been constructed to pro-.

' able control for each of the time periods in a This rapid rotation has the complete cycle or they have been so complicated as to make their cost of installment and operation a serious disadvantage.

It is one of my objects to provide a control device of this nature which will be accurate in 5 operation and capable of fine adjustment and yet which will comprise a relatively small number of working parts.

It is quite common practice to supply a battery of these centrifugal machines with sugar magma from one-common supply tank which holds a large amount of material to be processed. In such case the consistency of the material will always be the same at any one time for each individual machine in the battery although it vmay vary withea'ch new supply with which the supply tank is replenished. As the time periods "in the cycle of operation are determined by the consistency of the magmathose periods should always be the same for each machine in the 20 battery and when a new supply of a different consistency is introduced to the main tank all of the machines will require an equal amount of adjustment. If the fluctuations in consistency are frequent and if there are quite a number of machines in the battery there will be a corre- I spondingly large number of adjustments to be made at the same time and it is one of the objects of my invention to provide as a modiflca- I tion of my preferred means a master control device which will make the adjustments for each period in the cycle simultaneously for all centrifugals in the battery. One essential function of a control device of this character is that the mechanism for collective adjustment permits independence of centrifugal operation. Thus a device which required that all the centrifugals be started and stopped at the same time would be impracticalas in operation it is essential that the operative'be able to scrape out, start and load one centrifugal while the others are rotating and not tie up an entire battery of machines for the length of time required to scrape and load all of them. 1

The prior art includes certain pneumatic control devices which are intended to have afunction similar to that of my individual and master control machines but these machines have not proven satisfactory due to the intricacy of the mechanism and the resultant expense of installment and operation.

These and further objects of my invention will appear from a more detailed description of the preferred embodiment of my invention taken in connection with the accompanying drawings, in which,--

Fig. 1 is a'diagram of a centrifugal machine electrically connected to my improved individual control device;

Fig. 2 is a perspective view of my individual control device;

Fig. 3 is a detail elevation view of certain parts shown in Fig. 2;

Fig. 4' is a'detail elevation view of certain other parts shown in Fig. 2;

Fig. 5 is an elevation view of my master control device;

Fig. 6 is a vertical sectional view taken on the line 66 of Fig. 5 in which many of the parts have been omitted for clearness of illustration;

Fig. 7 is a detail plan view of the centrifugal machine brake operating mechanism;

Fig. 8 is a detail elevation view of the parts shown in Fig. '7 showing the centrifugal machine starting levers and their connections with the brake solenoid;

Fig. 9 is an end elevation, partly in section, taken onthe line 9-9 of Fig. 8; and

Fig. 10 is a sectional elevation of my preferred type of electrically operated spray water valve.

In Fig. 1, I have shown-diagrammatically at A a sugar purifying centrifugal machine of vacommon type, electrically connected to my improved control device indicated generally at B. The centrifugal machine A consists of the usual porous basket 1 suspended from vertical shaft 2 which is rotated by any suitable power operated means, such as the electric motor 3. Surrounding the basket 1 is the curbing 4 providedfor the purpose of carrying away the liquors as they leave the crude sugar during rotation of the basket. I have indicated diagrammatically at 5 an electrically operated water valve adapted to introduce water to the sprayer 6, and at '1 a solenoid adapted to break the circuit (not shown) to the motor 3 and operate the brake 8 to stop rotation of the basket 1. Before describing in detail my improved control device, I will indicate the manner in which the water valve 5 is electrically operated,- as well as the mechanism by which the solenoid '7 is connected to the brake 8 and to an electric switch in circuit with the motor 3 to stop the centrifugal machine.

Referring to Figs. 7, 8 and 9 wherein I have shown a type of starting and stopping mechanismwell known to the art, 300, 300 (Fig. '7), in-

dicate a pair of brake shoes fixed to the levers 301, which are pivoted on the common shaft 302 and adapted to be operated by the toggle joints 303, 303, which are linked together by a common pivot 310, rotation of which will either contract or expand the brakes against the centrifugal machine brake drum 290 in a well known manner. Fixed to the shaft 310 is a crank arm 308 which is rotated by the lever 304 to operate the brakes. Lever 304 (Fig. 9) is connected to the hand starting lever 305 by the swivel connection 306, the lever 305 being pivoted at 500. Also fixed to the pivot, 310 of the toggles 303 is the crank 311 which is connected by means of the rod 312 to the. electric starting switch 313 for the purpose of operating the same to introduce current to the centrifugal motor 3. By this well known mechanism, rotation of the lever 305 to its full line position, as shown in Fig. 9, breaks the toggles 303 to release the brakes 300 and close the switch 313. Reversal of this process by moving the lever 305 to its dotted line position will stop rotation of the centrifugal machine.

320, dog 316 and lever 321 in a counterclockwise direction as viewed in Fig. 8 to force the said dog 316 into its holding position in engagement withthe lever 305 to retain the said lever in starting position. If the lever 321 be now manually rotated in a clockwise direction the dog 316 will slip out from behind lever 305 to permit its rotation by the spring 314 to "oif position. The dog 16 is suitably beveled whereby it will slip into locking position when lever 305 is rotated to its starting position shown in full lines. The above-described mechanism is well known to the art and therefore it is considered that this brief description will suflice.

The function of the solenoid 7 is to rotate the retaining dog 316 automatically rather than manually as has been common heretofore. For this purpose the movable core 330 of the solenoid 7 is connected to one arm of the bell-crank lever 331 by the connecting link 332. The other arm of bell-crank lever 331 is connected at 333 to a rod 334 which is connected at 335 with the upper portion of a crank 324 fixed to the shaft 320. It will thus be apparent that when current is intro-.

duced to the solenoid '1 to attract its core 330 and rotate the bell-crank lever 331 ina counterclockwise direction the shaft 320 will be rotated to move the dog 316 into releasing position to'thereby stop rotation of the centrifugal machine.

InFig. 10 I have shown my preferred type of electrically operated water valve mechanism. 340 indicates an inlet pipe through which water or any other suitable spraying liquid is conducted to. the valve chamber 341 which communicates with the outlet pipe 342 leadingto the sprayer 6 (Fig. 1). The valve mechanism consists of the valve seat 343 into which fits the lower tapered end of the valve stem 344 which slides loosely within the cylindrical member 345. The said'member 345 comprises the movable core of a solenoid of the valve 5 and is adapted to be lifted vertically by the electric coil windings 346 through which current is introduced at certain times through the wires (d) and (0) whose exterior connections will be hereinafter more specifically described. When the valve is in closed position, as shown, with the stem 344 resting against the valve seat 343, the sliding core 345'rests against a fixed internal collar 350 and in this position it will be noticed that there is a slight clearance between the top of the cylindrical core 345 and a head 351 formed on the top.end of the. valve stem 344.

' When current is introduced to the windings 346 the core 345 immediately rises but does not lift the valve stem 344from its seat until the top of 1, 20 indicates a shaft which is constantly driven ous time intervals in the above described cycle of centrifugal operation. This mechanism mcludes two mercury switches indicated at 12 and 13 which at certain times are actuated to introduce current to the aforesaid solenoids 346 and '7, respectively. The said mercury switches and solenoids are connected in multiple series with electric current supply mains (a) and (b) in the following manner,the wire (c) leads from the main (a) to one terminal of the spray solenoid 346 (Fig.

10) of the water valve to the other terminal of which is connected the wire (d) which connects the solenoids 346 in series with the mercury switch 12 which is also connected to .the main (b) the wire (g) leads from the main (b) to the brake solenoid 7 which is connected in series with the mercury switch 13 by the wire (e), said switch 13-being connected to the main' (a) by the wire (I) For the purpose of starting certain parts in the control device B rotating to measure time, I

have provided a solenoid 10 whose operation will bermore fully described later but which is connected at one terminal to the main (a) and at the other terminal to the wire (h) leading to a control starting button or switch 11 which is connected to the main (b) by the wire (i). In operation the workman starts the basket 1 rotating by moving the starting lever 305 to its full line position, Figs. 1 and 10, and he then pours the proper-amount of crude sugar magma into the basket. He then immediately pushesthe button 11 to start the automatic measurement and control of the time periods. At a certain time thereafter the purging period will be complete and contact will be made in the switch 12 to actuate the water valve 5 to spray water against the sugar for a predetermined length of time, at the completion of which the connection at 12 will be broken and the water shut ofl. After another predetermined length of time the mercury switch 13 will be actuated to operate brake solenoid 7 to shut off current to motor 3 and apply brakesa to bring the basket 1 to a stop. 7

Referring now to Fig. 2 in which I have shown more in detail the device indicated at B in Fig.

at a slow rate of speed from a source of power indicated at 29 in Fig. 1. Loosely mounted on the shaft20, as shown in detail in Fig. 3, is the sleeve 21 which carries rigidly fixed to it the spray cam 22 and the brake cam 23. The spray cam 22" consists of a disc substantially circular I in shape but eccentrically mounted to produce :designated at 51. 'circ'ular disc mounted on center and having an a gradual raising and lowering of its cam follower 50, the highest portion of the cam being The cam 23 consists of a abrupt raised portion 75.

Also loosely mounted on the shaft are semicircular collar segments 24 and 25 which are maintained in frictional engagement with the shaft 20 by the encircling spring 26. The lugs 27 and 28 are formed integral with and perpendicular to thecollar segments 24 and 25, respectively, .65

held stationary by 'certainmechanism herein.- after described.

Erected in proximity to the cams 22 and 23 is the calibratedpost 40 which carries at its extremities the blocks 41 and 42 which may slide lengthwise of the post 40 and may be maintained at various elevations by means of the thumb screws'43 and 44 respectively. Pivoted at 45 to the upper sliding block 41 isthe lever 46 which carries at one end the cam follower 50 adapted to ride on the top of the cam 22 and be raised and lowered thereby. Mounted on the lever 46 above the cam follower 50 is the aforesaid mercury switch 12. This switch consists of.

ject in close proximity to, but at a slight distance from, the surface of the mercury when the glass vial is in a horizontal position as shown.

- From this arrangement of parts it will be seen that contact is made between the terminals 53 when the cam 22 raises its follower 50 to rotate the lever 46 about the pivot 45 in a clockwise direction by -a suflicient amount to cause the mercury 52 to flow to the terminal end of the vial 47 and contact both points. 7

block 42 is a horizontal member which, as shown in Fig. 4, is bifurcated at- 61. Pivoted at -30 Extending from one side of the lower sliding 63 to a supporting member 62 is'the lever 64 which extends parallel to and adjacent the member 60 and carries at approximately its central portion the pin 65 received by the bifurcated end 61 of the rigid member 60. Pivoted at to the lever 64 is the bell crank lever 71, the arm 72 of which carries the cam follower 73 which en-" gages the brake cam-23. The other arm 74 of the bell crank lever 71 carries at its extremity the mercury switch 13 which is in all respects identical withithe mercury switch 12 described above and which receives the terminals 76 of the brake solenoid circuit wires (e) and (f). The weight of the arm 74 and mercury switch 13 maintains the follower 73 in engagement with the brake cam'23, the raised portion 75 of which at times rotates the bell crank lever 71 in a clockwise" direction about its pivot 70 to cause the mercury inthe switch 13 to make contact across the terminals 76 to actuate the brake solenoid 7.

Rigidly mounted at a fixed elevation on the Post 40 is the block 80 from one side of which projects" the arcuate member 81 which is slotted at 82 to receive the block which is constructed to slide up and down in the slot 82 and be maintained at any desired elevation by the thumb screw 91.

Carried by the block 90 is the solenoid 10 which as stated above is connected in circuit with the push button switch 11 by the wires (:1) and (h). Pivotally mounted at 86 on the cam 22 is a springpressed latch 83 adapted to engage a nose 84 on the movable core of the solenoid 10 and when m such engaging position to rest against the stop 94 projecting from the cam 22 to hold the said cam 22 and the brake cam 23 from rotating counterclockwise with the shaft 20 as is permitted by their frictional driving connection. A spring 87' is connected at one endto the extremity of the latch 83 and at the other end to the cam 22 to quickly move the latch to a position against a second stop 88 upon retraction of the core 84.

Assuming that the parts are at rest in starting is rotating in a counterclockwise direction as indicated by the arrow, the cams 22 and 23 remain motionless, due to the fact that the projection 84 is in engagement with the latch 83. Current is now introduced to the solenoid 10 to withdraw the projection 84 from its engaging position with the latch 83 and the frictional drive above described rotates the cams 22 and 23 to measure the solenoid 10 is interrupted. The mercury switch 12 will now gradually move upwardly and slant downwardly at the terminal end as the forward end of the lever 46 is raised by the gradual high portion 51 of the cam 22. This first portion of the rotation governs the length of the purging period and it continues until contact is made between the terminals 53 which contact causes. allow of current to the spray solenoid 5 to start the spray period, which contact will be maintained until the high portion 51 has passed and the mercury switch 12 again assumes the position where contact across its terminals is broken. At that instant the spray period terminates and the drying period commences. Shortly thereafter the projection 75 on the brake cam 23 will move the, roller 73 to cause a tilting 'of the mercury switch 13 to make contact across the terminals 76, which contact is of sufficient duration to actuate the brake solenoid 7. This completes the full cycle of operation in the centrifugal machine but the cams 22 and 23 will continue to rotate until the latch 83, now resting against stop 88, again enases the nose 84 and is brought to rest against stop 94.

I have provided in my improved device a series of adjustments, one of which varies the purging time or the time interval from the moment the centrifugal is placed under the influence of my control device by actuation of the solenoid 10 to the moment when the mercury switch 12 is actuated to turn the wash water on, another adjustment which regulates the spraying time or the interval during which contact is made in the mercury switch'12 and still another adjustment for the drying period which changes the time interval from the moment when the contact in the spray mercury switch 12 is broken until contact in the brake mercury switch 13 is made.

To regulate the duration of electric contact in the spray mercury switch 12 the thumb screw 43 may be loosened and the block 41 and pivot 45 elevated or lowered to various positions. Assume, for example, that the glass vial 47 of the mercury switch 12 is in an exactly horizontal position when the follower 50- is resting on the lowest portion of the cam 22 as shown in Fig. 2. Assume also that" the space between .the surface of the mercury contained in the switch 12 and the extremities of the terminals 53 is of such an amount that just one quarter of a rotation of the 22 will cause contact to be made. The spray period commencing at that moment will occupy the nexthalfrotation of the cam 22 and contact will be brokenat the beginning of the lastuuartcr rotation which brings the cam 22 back to its initial position. If the block 41 benow raised a few notches on the rod 40 the mercury 1,984,302 position as shown in Fig. 2 and that the shaft 20 switch '12 will be slightly rotated in a counterclockwise direction about the pivot of the cam follower 50 which will lower the end of the vial 47 opposite to that receiving the terminals 53 and cause the mercury to flow to the lower end and slightly recede from the said terminals. With the parts so adjusted, somewhat more than one quarter of a rotation of the cam 22 will be required to bring the glass vial 47 to the position in which contact is made across the terminals 53. This contact, which is maintained during the spray pericd, will be broken at a correspondingly earlier time and by this adjustment the spraying time has been decreased. It will be apparent that such a regulation in the spraying time also has the effect of increasing the purging period, that is, the time interval between the moment when the cam 22 commences to rotate to measure time and the moment when the spray is turned on. Adjustment oi this purging period, however, can now be made in the following manner.

Again assume that the parts are in their initial position'as shown in Fig. 2, except that the adjustment of the spraying time which has just been made causes actuation of the spray solenoid when the cam 22 has rotated from its position as shown to the position where the point marked Z on the edge of the cam is directly under the cam follower 50. As thelength of the are on the periphery of the cam 22 between the point Z counterclockwise to the point where the follower 50 rests on the cam in its initial position as shown determines the length of the purging period, this period can be varied by changing the length of that arc. If we now loosen the bolt 90 and move the solenoid 10 downwardly a few notches the engagement of the nose 84 with the latch 83 which in turn abuts the pin- 94 will cause a corresponding clockwise rotation of the cam 22,-the frictional driving connection permitting the cam 22 to slip on the shaft 20. If we had desired to shorten the purging period by rotating the cam 22 slightly in a counterclockwise direction to elevate the starting position of the point Z,v raising of the solenoid 10 slightly would have accomplished this purpose as thefrictional driving mechanism would have caused the latch 83 to follow the nose 84 until it came to rest in contact therewith at its new adjusted position.

The last adjustmentto be made is that of the drying period time, which, it will be remembered,

is determined by the time at which the brake solenoid 7 is actuated by engagement of the raised portion 75 on the brake cam.23 with its follower 73. This adjustment should be made last due to the fact that in changing the initial position of the spray cam 22 the initial position ofthe raised portion 75 of the cam 23 relative to its follower 73 was also changed as the two cams rotateas a unit. The length of the are on the periphery of the cam 23 from the raised portion 75 counterclockwise to the point of contact between the cam and the follower 73 at the initial position of the said cam measures the time period from the moment the cams start to rotate to the moment when the brakes are applied. The diiference between that length of time and the sum of the lengths oftime of the purging and spraying periods which we have arready determined gives the drying time. If we causes a slight clockwise rotation of the lever I '64, which carries the said pin about its pivot 63.

* the .arm 74 without affecting the angle of inclination of the mercury switch 13. It should also be noted that by providing the lever 64 and pivoting the bell crank lever '71 to it rather than to the. arm directly the range of movement of the follower 73 in proportion to the corresponding movement of block 42 is greatly increased to thereby provide an increased range ofbraking time adjustment.

By the mechanism above described the various time periodsin the cycle of operation of a. single centrifugal machine can be controlled automatically and adjusted as desired. In practice the post 40 and arcuate member 81 are calibrat d as shown and a number of charts are prepared giving corresponding values in units of time for the calibrated settings computed on the basis of the speed ofrotation of shaft 20. In using these charts the calibrated number corresponding to the desired time in seconds for the spraying period is first determined and the spray block 41 adjusted to that number. As the position of the .block 90 which determines the purging time is dependent not only on the number of seconds desired for purging butalso' on the point on the cam 22 at which contact will be made in the spray mercury switch 12 which point is already fixed. by the spray adjustment just made, a secand chart is provided which gives settings'for. the purging blockv 90 corresponding to various spray block settings and various purging time.

. The last setting to bemade is that of the brake block 42 which fixes the drying period. For

intervals of convenience of-operation it is desirable to deterposition of the point Z on cam 22 determined by that setting and the raised portion 75 are I Y definitely fixed due to the integral construction cfthe cams 22 and 23 and that therefore a chart can be prepared which gives settings for the brakeblock 42 to correspond with various sprayblcck -41 settings and periods of time from spray on to brake .on.

preferred-embodiment of my invention an appa ratus adapted to control the various time intervals in the cycle of operation simultaneously for a'battery 'of centrifugals. The principle of operation of my master controlprmits theessen- 'tial independenceof centrifugal operation- Referring now to Figs. 5 and BI will describe a device adapted tocontrol. a'battery which for purposes of illustration I have assumed to'consist of four centrifugal machines. Correspondingly my control mechanism comprises four sep-- arate and distmct controlling units in all respects identical, which are mounted on a'commen shaft and linked together by a common adjusting mechanism. As-the description proceeds it will become apparent that I can provide a controlling mechanism for any number of centrifugal machines by the simple expedient of adding the objects of mytery. 'The A unit is shown in vertical section in Fig. 6 and my description of the parts which are duplicated in each unit will be confined to those shown in theA section although in Fig. 5 I have numbered some of the like parts of the other units to correspond with the numberings -in the A section.

I have indicated at an enclosed box-like structure adapted to house my improved master control device. Joumaled in suitable bearings 126 and 127 in the end walls of the casing 125 is the main shaft 128 which is continuously driven at a constant rate of speed by any suitable power operated means indicated by the sprocket wheel 129. In a manner similar ,to that described above for my individual control device this constantly driven shaft carries a spray cam and a brake cam for each centrifugal, each pair of which cams is mounted on a common sleeve and I at times rotated by the saidshaft 128'by means of a suitable frictional driving connection. 130 indicates one of the sleeves rotatably mounted on the shaft 128 and-carrying rigidly fixed to it the spray cam 131 and the brake cam 132. As in my individualcontrol device the spray cam'131 con- :sists of a disc which is substantially circular in shape but eccentrically mounted toimpart a gradual rising and falling motion to its cam 101- 5 lower 161. The brake cam 132 in my modified form consists preferably of a circular disc,

mounted on center, which in this case is provided with a depression or recess 133 which at certain times receives its cam follower 185. The spring 134 embraces frictional driving collar segments,

attached to the lugs 135 and 136 which lugs in my master control device engage the brake cam 132 to drive that cam, the collar 130 and the spray cam 131 being constructed to rotate as a unit in .a manner similar to that described for my in dividual control driving means.

Extending lengthwise of the machine and parallel to the maindriving shaft 128 is the shaft 140 which is eccentrically mounted in the bearings- 141 and 142 by means of the reduced, oncenter, end portions 143, 144. Rigidly fixed to the reduced end 144 of the shaft 140 is the spray dial 145 having suitable calibrations which co ordinatewith the index 146. Rotation of this dial turns the shaft 140 eccentrically for purposes which will be hereinafter described, and it may be maintained inlprg'per position, as indicated by the dial rnarlcingabira'rdeansJbf the bolt extending from the end wall of the box 125 through an arcuate slot 151 (Fig. 6) in thedial 145 and receiving the thumb nut 152.

Loosely mounted on the shaft 140 is the collar 153-which'is. maintained in suitable position lengthwise of the shaft 140 by the retaining collars 154 and 155 rigidly fixed to the shaft and 162 is gradually raised to make a mercury contact across the wires (1' and b to actuate the spray in any desired position by means of the bolt 174 extending through the arcuate slot 175 of the dial- 172 (Fig. 6) and receiving the thumb nut 176. Rigidly mounted on both ends of the shaft 171 are the parallel upwardly extending levers and 181, the upper extremities of which form bearings for the shaft 182. Loosely mounted on the shaft 182 is the block 183,,maintained in fixed position longitudinally of the shaft 182 by suitable retaining collars, from one side of which block extends the lever 184 carrying at its ex-' tremity the cam follower 185 resting on the brake cam 132 and also carrying the mercury switch which receives the terminals of the brake solenoid wires e and f. In operation the cam 132 which is circular in shape maintains the brake mercury switch 190 in slightly elevated inoperative position until the recess 133 arrives in position beneath the roller 185, at which time the lever'184 will drop and mercury switch 190 will be tilted to close the circuit to the brake solenoid on the first centrifugal machine to stop rotation of its basket.

I will now describe means for starting the spray and brake cams rotating to measure the time of their; respectively controlled intervals, which means is the same in principle of operation as that of the corresponding means in my individual control device, but which differs somewhat therefrom in its method of adjustment.

Rotatably mounted in suitable hearings in the end walls of thecasing 125 is the shaft 200 which is adapted to be adjusted to various angular positions by means of the calibrated dial having the arcuate slot 196 adapted to receive the bolt 197 with its thumb nut 198. Rigidly mounted at both ends of the shaft 200 are the gears 210 which are identical in pitch diameter and 'number of teeth and each one of which meshes with one of the gear segments 211 rotatably mounted on the shaft 128. Fixed to each of these gear segments 211 is a-member 212, the lower extremities of which members are connected by the flat bar 214, which bar has fixed to it by suitable bolts the solenoid 215. These connected parts are so designed and assembled that rotation of the shaft 200 in a clockwise direction as viewed in Fig. 6 will rotate'the gear segments 211, cross member 214 and solenoid 215 in a counterclockwise direction in the arcs of concentric circles whose common center is the axis of the shaft 128.

Pivotally mounted at 216 on the spray cam 131 is the spring pressed latch 217 adapted at times to abut against stop 218 and having an end be operated. Whencurrent is introduced to the solenoid 215, the projecting end of the core is retracted to permit the end 219 of the latch 217 to pass by and the spray and brake cams to rotate. v

So far in my illustration of the master control device I have described in detail the operation of the spray cam, brake cam and actuating solenoid of the A unit which controls the time periods in the operation of the first centrifugal in the tated by a frictional driving mechanism. The

shaft 140 carries four cam operated levers 160,

each one of which carries a mercury switch."

adapted to' operate a spray solenoid. The shaft 182 carries four levers 184 each one of which carries a mercury switch 190 adapted tooperate its brake solenoid. Fixed to the movable bar 214 are four solenoids 215, each one of which is adapted to hold its respective cams stationary until its core is withdrawn. It will thus be apparent that my mechanism provides for independence of operation of each control unit and that any one of them may be set in operation by actuating its solenoid 215 irrespective of whether any of the other control units are operating. All of the members of each control unit are assembled in the same relative position. Thus the brake cams I 132 (Fig. 6) are mounted so that when the latch 217 is in the position shown against the projection 220 of the core of the solenoid the recessed portion 133 in each disc will be in the position shown in that figure. As the lengthof the time periods in the various steps in the cycle of operation depends solely on the relative positions of the parts, these time periods will be the same for each centrifugal unit irrespective of when that control unit is set in operation.

It is the chief object of my master control to provide mechanism adapted to regulate the purging, spraying and drying intervals collectively for all centrifugals in the battery by one adjusting mechanism for each of those intervals.

On the same theory explained in the description of my individual control mechanism the duration of the spraying period, which is the first adjustment to be made, depends upon the angle of iiclination of the spray mercury switch 162. If the thumb nut 152 be loosened and the dial 145 turned; the shaft 140 will be eccentrically rotated about the axis of its reduced portions 143 and 144 to tilt each one of the mercury switches 162 the same degree and thus change the four spraying periods the same amount. The next adjustment is that of the purging time which can be varied by turning the dial 195 and its connected shaft 200 thereby rotating the gears 210, gear segments 211 and bar 214 with its four solenoids 215 and thus setting the four spray and brake came at a new initial position. The final brake adjustmentis obtained by tuming the dial 172 and shaft171'to swing the shaft 182 toward or away from the cams and thus increase or decrease the are on the four brake cams 132 measured in a counterclockwise direction from their recessed portions 133 to their respective cam followers 185. It will be noted that this adjustment will not materially alter the angle of.

inclination of the mercury switch 190.

From the above description it will be apparthe needs of the individual user without departing from the spirit of my invention which I do not wish' to limit except as indicated in the appended claims. 9

As one example of a modification which has found considerable favor among. the users of these machines I have frequently provided means for separating the various grades of liquor as they leave the curbing 4 (Fig. 1). Thus in operati'on the liquor which drains from the sugar during the purging period consists chiefly of impurities which have left the'crude sugar and is not of any particular value. At the'completion of the purging period when the spray water is'introduced the draining liquor may contain a fairly large amount of dissolved sugar and a.

lesser amount of impurities and it is desirable, to keep this grade of liquor separate from that derived from the purging operation. For this purpose a gate is provided beneath the-spout through which the liquor leaves the curbing 4,

which gate can be moved to direct the liquor into either one of two drain receptacles. As this gate shifting operation is performed first at the time the spray is turned on, and in preparation for the next cycle of operation again when the spray water isturned off, I may pro- 'vid'e-a useful automatic gate shifting mechanism comprising a gate shifting solenoid similar to the solenoids 5 and '7, which solenoid is electrically connected in the circuit leading from the spray mercury switch 12 to the spray solenoid 5 'to operate simultaneously therewith.

From ,the above description it will also be apparent that I have provided a deviceof this nature which strikingly contrasts with the prior art in its extreme simplicity and low cost of installmentand'operation. Some of the prior art machines are so designed that their time 'me'asuririg elements cannot continue to travel in the time measuring direction to return the parts to initial position but require additional mechanism adapted to reverse the direction of motion ofthese parts and retrieve them at the completion of their functions. It isconsidered that this is not a workmanlike'expedient, par ticularly insofar as these machines require an additional manual operation immediately after the completion of the functions of the time meas uringelements, and-that my device is superior insofar as it permits the time measuring cams 'to continue in their time measuring direction of rotation after their functions have been performed and finally come to rest without shock or undue force being exerted on the adjustable parts.

. There are some prior art devices particularlythose of the pneumatic type which havea function similar to that of my master control device l 3 trol means requires individual adjustment and timing but which are subject to criticism due to the fact that their calibrated adjustments are not centralized on one dial which'may' be isolated from the centrifugal machine itself and kept in a clean and well lighted part of the workroom, easily accessible to the'foreman. On thecontrary they provide mechanical spray controlling means mounted on the framework of each centrifug'al machine, each one of which spray conhence p ives such prior artcontrol devices oftheir function of master adjustment.

Throughout the description of my individual and. master control devices I'have described the brakes as being applied at a definite time interval after the spray water has been shut off to thereby provide a period of rotation wherein the sugar may be dried. In practice it is frequently advisable to shut off the power to the centrifugal machine driving motor and apply the brakes at a short time before the spray water is shut off. The common type of centrifugal machine carry-- ing a capacity loadof crude sugar and rotating at a speed of approximately 1200 R. P. M. can be brought to a stop in approximately seconds by a full application of the brakes. It has been exerted by the rotation of the basket is still suflicient to eliminate a large amount of liquor. This period of rotation which has been increased in time by the lighter brake application must therefore be computed as constituting part of the drying time and for that reason the adjustments provided in an individual or master centrifugal control must be of such a nature that they permit application of brakes before the completion of the spraying period particularly if a brief drying period is desired. Some of the prior art devices,

particularly of the pneumatic type, do not provide for such an adjustment which is, however, a distinct feature of my invention.

Having described my invention what I wish to claim and secure by Letters Patent is:

1. In a device for automatically controlling the timing of the cycle of operation of a centrifugal machine having a wash fluid valve, the combination of cam mechanism having dwell portions and actuating portions, shaft means forrotating said cam mechanism during the cycle of operation'to measure the timing of the steps constituting the said cycle, frictional drive means connecting the shaft means and the cam mechanism, cam following mea-ns adapted to respond to the configuration-of said cam mechanism, means actuated by said cam following means to open the wash fluid valve at apredeterminedtime after the beginning of the time measuring rotation of the cam mechanism and -to close the said vaive' at a second predetermined time after the beginning of said rotation, means to vary the initial relative positions of the actuating portions of the cam mechanism and the cam following means to alter the first of said predetermined time periods and means to vary the extent of said actuating pore tions to alter the second of said predeterminedtime periods.

2. In a device for automatically controlling the timing of the cycle of operation of acentrifu'gal machine having an electrically operated wash fluid valve, the combination of an electric circuit for operating said valve, cam mechanism comprising a substantially circular disc eccentrically mounted to provide dwell portions and actuating portions, means for rotating said cam mechanism during the cycle of operation to measure the ofthe steps constituting-the said cycle,-

cam following means adapted to respond to the configuration of said cam mechanism, electric switch means in said circuit and actuated by the cam following means to open the wash fluid valve at a predetermined time after the beginning of the time measuring rotation of the cam mechanism and to close the said valve at a second predetermined time after the beginning of said rotation, means to vary the initial relative positions of the cam mechanism and the cam following means to alter the first of said predetermined time periods and means to vary the initial position of the electric switch means relative to the cam mechanism to alter the second of said predetermined t-ime periods.

3. In a device for automatically controlling the timing of the cycle of operation of a centrifugal machine having an electrically operated wash fluid valve, the combination of an electric circuit for operating said valve, .cam mechanism having dwell portions and actuating portions, means for rotating said cam mechanism during the cycle of operation to measure the timing of the steps constituting thesaid cycle, cam following means adapted to respond to the configuration of said cam mechanism, an electric switch having ter-- minals and a contact in said circuit adapted to be opened and closed by the cam following means to open the wash fluid valve at a predetermined time after the beginning of the time measuring rotation of the cam mechanism and to close the said valve at a second predetermined time after the beginning of said rotation, means to vary the initial relative positions of the cam mechanism and the cam following means to alter the first of said predetermined time periods and means to vary the initial relative positions of the contact and terminals of the switch to alter the second of said predetermined periods.

4. In a device for automatically controlling the timing of the cycle of operation of a centrifugal machine having an electrically operated wash fluid valve, the combination of an electric circuit for operating said vvalve, cam mechanism comprising a plurality of cams adapted to rotate as a unit, shaft means for rotating said cam mechanism during the cycle of operation to measure the timing of the steps constituting the said cycle,

. means to arrest rotation of the cam mechanism after a complete revolution in the time measuring direction, means for retracting said arresting means to release the cam mechanism from its arrested position for rotation in the next succeeding cycle, cam following means adapted to respond to the configuration of said cam mechanism, an electric switch having terminals and a contact in said circuit adapted to be actuated by said cam following mean-s to open the wash fluid valve at a predetermined time after the beginning of the time measuring rotation of the cam mechanism and to close the said valve at a second predetermined time after the beginning of said rotation, means actuated by said cam mechanism for stopping rotation of the centrif- -ugal at a third predetermined time after the beginning of said rotation, means to vary the position of the arresting means whereby to change the initial position of the cam mechanism to alter the first of said predetermined time periods,

means to vary the initial relative positions of the contact and terminals of the switch to alter the second of. said predetermined periods and means centrifugal machines having-a wash fluid valve for each centrifugal, the combinationof a-time control unit for each centrifugal including time measuring means adapted to rotate .to measurethe timing in the cycle of its centrifugal, means for rotating the time measuring means ofceach ,of the units independently of those of theotherunits, means for arresting the rotation of the time measuring means of each unit when the rotation thereof in the time measuring direction-after the completion of one cycle has returned it to start;- ing position for the next succeeding cycle, means actuated by each unit for opening the wash fluid valve of its centrifugal at a predetermined time after the beginning of rotation of its time measuring means and for closing the valve at a second'predetermined time after the beginning of said rotation, means actuated by each unit to stop rotation of its centrifugal at a third predetermined time after the beginning of rotation of its time measuring means, means for varying the first of said predetermined time periods simultaneously for all the centrifugals, means for varying the second of said predetermined time periods simultaneously for all the centrifugals and means for varying the third of said predetermined time periods simultaneously for all the centrifugals whereby the time periods in the cycles of all the centrifugals are independently controlled and collectively variable.

6. In a device for automatically controlling the timing of the cycles of operation of a battery of centrifugal machines having a wash fluid valve for each centrifugal, the combination of a time control unit for each centrifugal including time measuring means adapted to rotate to measure the timing in the cycle of its centrifugal, means for rotating the time measuring means of each of the units independently of those of the other units, means for arresting the rotation of the time measuring means of each unit when the rotation thereof in the time measuring direction after the completion of one cycle has returned it to starting position for the next succeeding. cycle, means actuated by each unit for opening the wash fluid valve of its centrifugal at a predetermined time after the beginning of rotation of its time measuring means and for closing the valve at a second predetermined time afterthe beginning of said rotation, means for varyingthe first of said predetermined time periods simultaneously for all the centrifugals, and means for varying the second of said predetermined time periods simultaneously for all the centrifugals whereby the time periods in the cycles of all the centrifugals are independently controlled and collectively variable.

' vI. In a device for automatically controlling the timing of the cycles of operation of a battery of centrifugal machines having a wash fluid valve for each centrifugal, the combination of a time control unit for each centrifugal including time measuring means adapted to rotate to measure the timing in the cycle of itscentrifugal, means for rotating the time measuring means of each of the units independentlyof those of the other units, means for arresting the rotation of the time measuring means of each unit when the rotation thereof in the time measuring direction after the completion of one cycle has returned it to starting position for the next succeeding cycle, means actuated by each unit for opening the wash fluid valve of its centrifugal at a predetermined time after'the beginning of rotation of its time measuring means and for closing the trifugals.

8. In a device for automatically controlling the timing of the cycles of operation of a battery of centrifugal machines having a wash fluid valve for each centrifugal, the combination of a time control unit for each centrifugal including cam mechanism adapted to rotate to measure the timing in the cycle of its centrifugal, means for rotating the cam mechanism of each of the units independently of those of the other units, cam following means for each of the units adapted to respond to the configuration of its cam mechanism, means actuated by the cam following means of each unit to open its wash fluid valve at a predetermined time after the beginning of the time measuring rotation of its cam mechanism and to close the said valve at a second predetermined time after the beginning of said rotation,

, means actuated by the cam following means of each unit for stopping rotation of its centrifugal at a third predetermined time after the beginning of said rotation, means for varying the first of said predetermined time periods simultaneously for all the centrifugals, means for varying the second of said predetermined time periods simultaneously for all the centrifugals and means for varying the third of said predetermined time periods simultaneously for all centrifugals whereby the time periods in the cycles of all the centrifugals are independently controlled and collectively variable. a

9. In a time period control device the combination of a cam having dwell portions and actuating portions, cam following means comprising a lever having one end in engagement with the cam and its other end pivoted to a support in proximity to the cam, an electric circuit including a fluid switch mounted on the lever and havingpontact means for closing the circuit with the fluid upon actuation of the cam following means by the cam and means for varying the position of the pivoted end of the lever whereby to change the duration of contact between the fluid and said contact means during each revolution of the cam.

10. In a device for automatically controlling the time periods in a cycle of operation comprising a plurality-of steps, the combination of a plurality of cams each having dwell and actuating portions, means for rotating said cams to measure time, cam following means adapted to respond to the configuration of one of said cams, means actuated by said cam following means to perform two consecutive steps in said cycle, means to vary the extent of the actuating portion of the cam to alter the time period of the second of said steps, means to vary the initial position of the cam following means relative to the actuating portion of the said cam as thus varied to alter the time period of the first of said steps, a second cam following means adapted to respond to the configuration of a second of said cams, means actuated by said second cam following means to perform a third step in said cycle and means to vary the initial relative positions of the actuating portion of the said second cam and its said cam followingmeans to alter the time period of ,the third of said steps.

REINIER P. DE VRIES.

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