US1641748A - Sampling apparatus and system - Google Patents

Description

S e t. 192

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Sept 1927' c. G. DRESSER ET AL SAMPLING APPARATUS AND SYSTEM Filed Jan. 17 1921' s Sheets-Sheet 5 fill I a 7 Patented Sept; 6, 1927.

UNITED sTATss PAT NT CLARENCE G. mmssna, or srr. mANcoIsnIssounr, Ann rLoYn s. Youmsi's'r, oi COLLINSVILLE,1ILLINIS.

SAMPLING: APPARATUS ND SYSTEMS.

Application m ma 17; 1921. Serial No. 457,825.; I

This invention relates to a sampling a'pparatus and system adapted for the sampling-of various materials, such as ores, etc.-

One of the objects of this inventionis to {iprovide an apparatus and system for sampling dry or wet materials flowing past a certain point, and which will take a typical "sam le at frequent or long intervals dc pen ing upon the uniformity of the product 1 flowing and the quantity desired as a sample. Another object is to provide a cutter which is so constructed and arranged as to cut the same fractional part from each part of the stream.

Another object is to provide a cutter which is so constructetd and operated as to avoid errors, and more particularly accumulation of errors due to the particles striking one edge or blade of the cutter and so as to eliminate errors due to the rebounding of the particles of different specific gravities and elasticities.

Another object is to provide a cutter which is constructed and arranged so as to travel through the stream at a uniform velocity with an idle period while out of the stream ath. p Another object is to provide a cutter which is constructed and arranged to move through the stream in cycles, each cycle including a forward and reverse movement. Another object is to provide a system in which a series of cutters, each corresponding to its particular stream, are operated through the medium of driving mechanism common to all of the cutters.

Another object is to provide an apparatus in which a series of successively cut samples are measured during each of the series of.

4 successive periods, means being also provided for integrating the total samples cut at the end of a series of successive periods, and the integrations being recorded progressivel Another object is to develop a method of sampling materials in which a cutter is moved in a series of cycles back and forth -through the stream at a uniform velocity, an idle period being provided in each cycle when the cutter is out of.the stream path.

Another object is to provide a method in which the samples are measured and re- -successive perlods being also integrated.

companying drawings, in which: I

each of a series ofsuo'cessive eriods, and the total samples-at the end 0 a series of Further objects will appear from the detail descrlption taken in connection with the ac Figure 1 is a side elevation, partly in section, of a cutter and connected mechanis embodying this invention;

Figure 2 is a plan of Figure 1;

Figure 3 is a section on the line 3-'3, Figure 1; 06: Figure 4 is a side elevation, part1 in section, of the alternating mechanism or operating the cutter, showing alsothe driving mechanism therefor;

Figure 5 is a section on the line 5-5, Figure Figure 6 is aplan of the driving mechanism;

Figure 7 is a side elevation, partly in sectlon, showing a complete apparatus or. s stem, lncludmg also the measuring mec an1sm;

Figure 8 is a detail of the measuring mechanism;

Figure 9 is anenlarged section on the line 9-9, Figure 8;

-Figure 10 is a plan showing a series of i cutters driven from a common 1 driving mechanisnrf; and

Figure 11 is a section on the line 11-11, 85, Figure 10, showing another form of cutter mechanism. 1

Referring to-the accompanying drawings, andmore particularly to Figures 1, 2 and 3,

1 designates a'carrier for the cutter comprising'a pair of blades 2, which are arranged radially of a shaft 3 mounted in bearings 4 on supports 5. The shaft has fixed thereto collars 6 and 7 which support the carrier radially on the shaft so that the carrier is arranged to move'with the shaft. The shaft has fixed thereto a sheave 8 adapted to receive a cable 9 so as to-be driven from a suitable mechanism, as hereinafter described. The carrier expands below 100 the cutter, asshown in Figure 3, and has. a conduit extension 10 entering a hood 11 carried by a bracket 12 fixed to the shaft 3 and fitting over a casing 13 mounted on a support 14 and provided with an outlet corded, the measurements succeeding through 15. i

The cutter is arranged to be oscillated underneath a spout 16 so that the cutter will pass through the stream of material and cut therefrom a sample each time that such passage takes place. This sample will then flow downwardly through the conduit and into the casing 13, leaving the latter by the outlet 15. In view of the fact that the cutters are arranged radially, the o ening of the cutter at any'point is in accor ance with its linear movement at that point; accordingly the cutter will cut the flowing stream in such a manner as to cut the same fractional part from each part of the stream, irrespective of shape or cross-sectional area of the stream.

Referring now to Figures'4, 5 and 6, the cable 9 passes around another sheave 2O fixed to a hub 24 on a shaft 21 mounted in a bearing 22 on a sup ort 23. To this shaft is fi xed the hub 24 0 the yoke 25 having a lower hub 26 resting on a worm wheel 27 fixed to a shaft 28 mounted in a bearing on a sup ort 29. The shaft 28 extends loosely into t 1e hub 24 and is threaded inside of the yoke at 30. This shaft has further keyed thereto a pair of dogs 31 and 32 arranged to cooperate with a dog 33 having a threaded engagement with the shaft, and provided with lugs 34 embracing a iii) 35 on the yoke.

The worm wheel 27 has meshing therewith a worm 36 fixed to a shaft 37, having also fixed thereto a gear 38 meshing with a pinion 39 on the shaft of an electric motor 40, which is of the constant speed type. This motor is electrically connected in circuit with a controller 41 adapted to control the direction of movement of the motor.

' This controller may be of any suitable construction, being in the form of the usual reversing switch, the moving element 42 of which is connected with a link 43 having a head 44 embracing a shank 45 slidable in bearings 46 and 47 and having a rack 48 meshing with a pinion 49 fixed to 'thcshaft 21. The shank further has collars 50 and 51 arrangedto engage with the head 44.

The motor will operate through the reducing gearing to rotate the shaft 28 at a constant and uniform speed in one or the other direction depending upon the direction of rotation of the motor. The rotation of the shaft 28 will cause the threaded part 30 to move the dog 33 either up or down, depending upon the direction of movement of the motor. The shaft 28 will, however,

rotate idly in the yoke 25, while the dog 33 is out of engagement with either of the dogs 31 or 32. Assume now that the shaft 28 rotates from right to left, Figure 4, or in the direction of the arrows, Figures 5 and 6, this, will cause the dog 33 to move upwardly on the shaft and in the yoke until the dog 33engages with the upper do" 31. Upon such engagement, the dog 31, which has been rotating with the shaft, will shift the yoke through a part of a revolution, carrying the sheave 20 with it. The movement 'of the shaft 21 with the yoke will, however, also, through the connection of the pinion 49 with the rack 48, shift the shank 45 to the right, Figure 4, thereby causing the collar 50 by its engagement with the head 44 to shift the movable element 42 of the switch, thereby reversing the direction of movement of the motor. The motor will now rotate the shaft 28 in the reverse direction, causing the dog 33 to travel downwardly and out of engagement with the dog 31, thereby not only stopping further movement of the yoke, but moving the dog 33 downwardly to engage the lower dog 32. During a predetermined interval measured by the movement of the dog 33 downwardly along the shaft, the yoke and its connected sheave 20 will remain stationary. Upon engagement of the dog- 33 with the dog 32,- the yoke will be again shifted or oscillated but in the reverse direction. This will, however, cause the collar 51 to be shifted to the left, Figure 4, thereby moving the switch element 42 to the left and again reversing the motor so as to cause the direction of movement of the shaft 28 to be again reversed. Accordingly the reverse movement of the yoke will be terminated and it will remain stationary for a predetermined period until the dog 33 again travels upwardly on. the shaft and engages the dog 31.

\Vith this mechanism, therefore, there is imparted to the sheave20, an alternating movement, first in one direction and then in the other direction, with a definite dwell or period of rest between each alternation. In view of the fact, however, that the motor is a constant speed motor, and in view of the fact that the gearing is a constant speed gearing. the movement imparted to the' sheave will be ibllDlfOI'm' movement.

The alternating movement imparted to the sheave 20 Will be transmitted to the sheave 8 and the shaft 3 by the cable 9. Accordingly the shaft 3 has-imparted to it a corresponding alternating movement with a dwell or period of rest between the movements, and this movement is a constant one so that the movement imparted to the cutter, while an alternating movement, is such as to cause the cutter to pass through the stream at a constant or uniform velocity.

Accordingly, the alternating mechanism is so constructed as to move the cutter through the stream in opposite directions in cycles, each cycle including a forward and a reverse movement, but this cutter passes through the stream at a uniform velocity. The displacement of the cutter at each movement thereof need only be slightly greater than the distance across the stream. However, since -upon the movementof the cutter and the actual length the cutter has an idle period after it is out of the stream path at the end of each half cycle, this idle period may be used to correspond to a movement of the cutter at a uniform velocity along an extended path. Therefore, the cutter will take or cut a definite fractional part of the stream, and in fact a definite fractional part from each art of the stream. The magnitude of this ractional part depends upon the length of the cutter path while the cutter is in the stream as related to the total length of the imaginary path of the cutter; this depends ratio of the gearing, the speed of of the cutter travel before it is reversed.

In view of the fact that the cutter travels through the stream at a. uniform velocity, the amount'of the sample is determined; this sample is a uniform section of the stream for the reason that the amount out from the stream at any point is in accordance with the linear movement of the-cutter at that point, so that a correct sample will be taken, irrespective of the shape or cross-section of the stream. Since the cutter moves through the stream in cycles, each cycle including a forward and a reverse movement. errors due to difference in specific gravities and rebounding of particles striking the edge of the cutter will be compensated for and eliminated, since the errors due to this effect, when the cutter moves through the stream in one direction, are cancelled or eliminated when the cutter moves in the opposite direction through the stream.

It will be noted that the cutter moves back and forth through the stream in successive cycles with an idle period when out of the stream path, and this idle period is variable so as to increase or diminish the fractional part taken from the stream. The velocity of the cutter when passing through the stream is not, however, only uniform but also fixed since it is not varied or adjusted, in view of the fact that adjustment of a fraction is varied by changing the duration of the idle period, This in effect adjusts what may be considered the total travel of the cutter, while the travel through the stream part and the velocity of the cutter through the fixed as well as uniform. By maintaining the velocity of the cutter while passing through the stream path fixed as Well as uniform, variations in its action are eliminated so that the action of this cutter in taking a fraction is uniform. By obtaining adjustment through a variation in the idle period, the fractional portion can be closely adjusted to suit requirements, and this adjustment is especially fine in View of the screw and nut mechanism employed which stream remains enables the idle period to be closely adjusted. This is especially advantageous where a small but uniform and characteristic sample is'desired during a days run in a large plant. Thus if, for instance, it is desired to obtain some odd fraction, for instance, one part in 10,100,the mechanism can readily be adjusted to 'obtain that result, and in view of the fact that the mechanism is so constructed as to obtain a typical sample with great accuracy, the total material passing through a plant during a days run can e accurately determined even with a large multiplying factor as noted above.

' eferring now to Figures 7, 8 and-9, the outlet 15 discharges into a hopper 60 which has a pipe 61 conductingthe material to t e measuring mechanis The pipe 61, therefore, leads to a channel 62 in a support 63, which connects with a beam or measuring element 64 in the form of a long pipe supported by a bearing 65 fixing one end of the measuring element, the element being closed and provided with a recordin operating with a record 6 on any suitable recording mechanism 68. The free end of the measuring element supports a reservoir or accumulator 69, the bottom of which connects interiorly with the free end of the measuring element, the cover of which is provided tablish atmospheric pressure within the reservoir or accumulator 69. The bearing 65 has a base portion 71 mounted on a bracket 72-so as to be slidable therealong. The bearing further has a cap retained by bolts 73 which pass through a slot 74 in the bracket 72. In this way, the bearing can be moved along the bracket to fix the point free and bein element 66 c0- ment 64 in order to initially adjust it. As

other end of this.

with a perforated plug 70 toesan additional adjustment, the measuring element is. provided with is movable along a screw 76 mounted in brackets 77 on the measuring element.

Connected by a channel 78 with the channel- 62 is a cylinder 79 having a stem 80 rising therein and provided with a. valve seat at its upper end closed by a valve 81. This valve is mounted on a cross-head 82 movable in guides 83 and connected with a yoke 84 provided with a fork 85 guided on-the shaft 86. This yoke has acam roll 87 cooperating with a cam 88 onv a worm wheel 89 on the shaft 86, a leaf spring'94 moving the yoke down. The worm wheel meshes with a worm 90 on a shaft 91 provided with a bevel gear 92 mashing with a bevel gear93 on the shaft 28, whereby the alternating movement of the shaft 28 will cause a cor responding movement of the shaft 86. The cylinder 79 has an outlet 95 from which leads a pipe 96. This pipe discharges into a weight 75 which past the charging-into a tank 99 mounted on a platform of a suitable scale 100.

The cam 88 may be in the ositionshown.

in Figures 7 and 8 when-the e ement 33 is in the position shown in Figures 4 and 7, at.

which time the 'valve 81 is closed and the cutter is out of the stream path. As the shaft 28 continues to move in the same direction the cam '88 will move underneath the roll 87, raisethe valve 81 and drain the accumulator 69 to the zero level 101 passing through the valve seat, the length of the cam being sufficient to accomplish this draining. After the 'cam has moved past the roll, thereby closing the valve 81, the element 33 engages the upper dog 31 and causes the cutter to pass through the stream. whereby the sample will be caused to flow into the ho per 60.

The samp e taken by the cutter and discharged into the hopper 60 will flow through the channel 62 and along the measuring element and into the accumulator 69 so as to accumulate in the latter, thereby causing the measuring element to flex in accordance with the accumulation. The weight having been'adjusted so that the recording element 66 will be at 0 when the level is at 101, as the-accumulation in the accumulator 69 rises above that level, the measuring element will flex in accordance with that acc umulation so that the recording element 66 will move on the recorder 67 and record,

thereon the weight or measurement of the sam le.

T e cutter having now passed through the stream, and remaining at rest, the direction of movement'of shaft 28 is reversed, thereby causing reversal of cam 88, and when the element 33 again reaches midosi- .tion (Figures 4 and 7), the cam will ave been moved back to engage roll 87. This cam will then upon further movement move the valve 81 from its seat, thereby allowing the accumulation in the accumulator 69 to flow through the element 64 upwardly through the stem into the cup 79 and discharge by the pipe 96 into the cup 97 from whence the pipe 98 discharges the same into the tank 99. The cam will now move roll thereby closing the valve before the element 33 engages the lower dog 32, so that the accumulator has been drained to zero and is ready to receive the next sample when the cutter again passes through the stream.

The record 67 may be of any suitable form and may be divided into any suitable eriods, such as eight, twelve or twenty-four liour periods of a days run, or even into half or quarter hour periods of that run. The record may further be calibrated in. tons, or any other suitable unit. By adjustment of the bearing 65 and the weight ing, the recording element can be ma e to correspond with the calibration of the re-- corder, while the gearing 'betweenthe shaft 28 and the cutter on one hand and the cam 88 on the other hand, can be so proportioned that one complete movement of the. shaft cutter and cam will correspond, for instance, to the unit of time, such as the hour, half hour or quarter hour to which the record is calibrated.

The record will at any time show the tonnage of the material which'has flowed past a given point during a given interval or unit of time. The total samples during any number of units of time, for instance, during a days run are integrated in the tank 99 and integrations are indicated b the scale 100. Accordingly not only wil the accumulating samples be measured and recorded progressively during each interval or unit of time during a days run, but the total will also be integrated, and sincet-he recorder can be directly calibrated in tonnage and since the scale 100 can also be calibrated directly, the tonnage passing a given point during an interval of time or during any part of that interval, as well as the total tonnage'during a days run, can readily be determined. Moreover, the record will also show fluctuations in the tonna e.

5 single driving mechanism may be used to drive any number of cutters as well as their corresponding measuring mechanisms. This is shown in Flgures 10 and 11 in which one such mechanism is shown at A and another at B, each cutter mechanism corresponding to its articular stream supply. The cable 9 lea ing from the sheave 20 passes over a sheave on a counter shaft 111 which has a sheave 112, which has passing over it a cable 113 passing over the sheave 8 of the mechanism A and a sheave 108 over the mechanism B. The mechanisms A and B may be operated directly from the shafts 21 and 121 of the sheaves .8 and 108, respectively, but in the specific construction, the cutter mechanism B illustrates another embodiment of this inven tion in which the cutter 2 is mounted on a carrier 114 rolling on a track 115 and connected directly to the cable 113 so that this cutter will move so as to remain parallel to a fixed direction. In such a construction,

the cutter blades 2 are parallel instead ofradial, while the conduit 116 will discharge into a hopper 117 having a spout 118 discharging into a hopper 60. The outlet of each mechanism A and B may discharge into its individual hopper for its individual measuring mechanism, but all of these measuring mechanisms may be driven from the shaft 28, for instance, by providing .each shaft 91 with a sprocket 119 and. connecting i be made the details u out departing from the s irit of thisinventhe same .by a chain 120; Accordingly all of the mechanisms are driven in unison and each measuring mechanism will sample its individual stream and will measure and record the samples individually.

'It is obvious that various changes may of construction withtion; it is, t erefore, to e understood that this invention is not to be limited to the specific details shown and described.

Having thus decribed this invention, what is claimed is:

1. In the art of sampling materials in which a cutter periodically takes a. sample from a flowing stream, the process comfprising, passing the cutter back and orth through the stream at a uniform velocity.

2. In the art of sam ling materials in which a cutter periodica ly takes a sample from a flowin stream, the process comprising, passing the cutter through the stream at a uniform velocity in successive cycles with an idle period when out of the stream] vpath.

3. In the art of sampling materials in which a cutter periodically takes a sample from a flowing stream, the process com rismg, passing the Y cutterback and. 'orth through the stream at a uniform velocity in successive cycles with an idle period when j l out of the stream path.

mg, passing a cutter, point is in accordance at that point, back and forth at a uniform which a cutter periodica 4. In the art of sampling materials in which a cutter periodically takes a sample from a flowing stream, the precesscomprising, passing a cutter, whose o ening at any point is in accordance with its inear velocity at that point, back and forth through the stream.

5. In the art of sam ling materials in" which a' cutter periodica ly takes a sample from a flowing stream, the process comprising, passing a cutter, whose opening at any point is in accordance with its linearvelocity at that point, through the stream in successive cycles wit-h an idle period when out of the stream path.

6. In the art of which a cutter from a flowing sampling materials in periodically takes a sample stream, the process compriswhose opening at any with its linear velocity velocity through the stream.

7. In the art of sam ling materials in Whicha cutter periodica from a flowing stream, the process comprising, passing the cutter at a uniform velocit through the stream in successive cycles with an idle period when out of the stream path, and varying the duration of the idle .8. In the art of sam ling materials in ly takes a sample from a flowing stream, the process com rising, successively cutting the same de ite periods, automaticall ly takes a sample period.

fraction from all partsof the stream irrespective of the shape entrees-sectional area of the, stream. J 9. In the art of sampling materials, the process comprising, cutting successive sam ples. fr'omthe stream, measuring the samples dur ng each ofa series of successive periods, and automatically. recording such measurements during each of said periods.

10.'In the art of sampling materials, the process comprisin cutting successive'samples from the stream, measurin the samples .dllrlllg' each of a series of successive recording such meas- .urements durlng eac of said periods, and integrating the total samples cut at the end of a series of successive periods.

11. A sampling apparatus, comprising, a cutter, and means for moving said cutter at a uniform velocity through the stream first in one. direction and then in the opposite direction. 1 12. A sampling apparatus, comprising, a cutter, means for moving said cutter in-successive cycles through the stream, cooperatingmeans for causing said cutter to have an idle period in each cycle when out of the stream path, and cooperating means for causing said cutter to move at a uniform velocitythrough the stream. I

13. A sampling apparatus, comprising, a cutter, means for moving-said cutter in successive cycles through the stream, each cycle including a forward and a reverse movement,

cooperating means for causing said cutter to 15. A sampling apparatus,

comprising, a

' cutter, and means for moving said cutter through the stream first in one direction and then in the opposite direction, through an arcuate path the opening of the cutter at any point being in accordance with its linear velocity at that point. 16. sampling apparatus for taking separate'samples from different streams, compr sing, a series cut its corresponding stream, alternating. driving mechanism having a uniform velocity, and connections from said mechanism to the respective cutters.

' 17. A sampling apparatus for taking sepa- 1 5 rate samples from different streams, comprising, a series of cutters each adapted to cut its corresponding stream, alternating mechanism, connections from said mechanism to the respective cutters, and driving of cutterseach adapted. to 12 mechanism connected to drive said alternating mechanism, said driving mechanism having means for causing an. idle period following each movement of said alternatingv mechanism.

18. A sampling apparatus, comprising, means for cutting successive samples, means for measuring the samples, and means for progressively recording such measurements.

19. A sampling apparatus, comprising, means for cutting successive samples, means for measuring the samples cut during each of a series of successive periods, and means for recording such measurements during each period.

20. A sampling apparatus, comprising, means for cuttingsuccessive samples, means for measuring the samples cut during each of a series of successive periods, and means for progressively recording such measurements during each period.

21. A sampling apparatus, comprising, means for cutting successivesamples, means for measuring the cut samples, and driving mechanism connected to drive said cuttin means and said measuring means in time relation.

22. A sampling apparatus, comprising,

means for cutting successive samples, means for measurin the samples out during eachof a series 0 successive periods, and driving mechanism connected to drive said cutting means and said measuring means in timed relation.

23'. A sampling apparatus, comprising, a cutter, means for successively moving said cutter through the stream and adapted to cut therefrom a series of fractional samples,

means for measuring the cut samples, and

driving mechanism connected to drive said cutter moving means and said measuring means in timed relation.

24:. A sampling apparatus, comprising, a cutter, means for successively moving said cutter through the stream and adapted to cut therefrom a series of fractional samples, means for measuring the samples cut durin each of a series of successive periods, an driving mechanism connected to drive said cutter moving means and said measuring means in timed relation.

25. A sampling apparatus, comprising, a cutter, means for successively moving said cutter at a uniform velocity through the stream and adapted to cut therefrom a series of fractional samples, means for .measuring the cut samples, and driving mechanism connected to drive said cutter moving means and said measuring means in timed relation.

26.. A sampling apparatus, comprising, a

cutter, means for successively moving said cutter through the stream, first in one direction and then in the opposite direction, and adapted to cut therefrom a series of fractional samples, means for measuring the cut samples, and driving mechanism connected to drive said cutter moving means and said measuring means in timed relation.

27 A sampling apparatus, comprising, a series of cutters each adapted to cut a corresponding stream, a series of cutting devices each adapted to measure the samples cut from a corresponding stream, and driving mechanism connected to drive said cutters and said devices.

28. A sampling apparatus, comprising, a series of cutters each adapted to cut a corresponding stream, alternating mechanism connected to drive said cutters, a series-of cutting devices each adapted to measure the samples cut from a corresponding stream, and driving mechanism connected to drive said alternating mechanism and said devices.

29. A sampling apparatus, comprising, a'

rotatably mounted and radially extending carrier, axially disposed cutter blades extending radially on said carrier, a conduit on said carrier and leading from said blades, and means for oscillating said carrier.

30. An apparatus of the class described, comprising, means for taking a fractional portion of the material, accumulating means therefor, means for measuring the accumulation, and means for discharging the measured accumulation at intervals.

31. An apparatus of the class described, comprising, accumulating means, means for measuring the accumulation, and means for discharging the measured accumulation automatically after a predetermined accumulating period.

32. An apparatus of the class described, comprisin means for taking a fractional portion 0 the material, an accumulating measuring element therefor adapted to receive and measure the material, and means for recording .the measured accumulations.

33. An apparatus of'the class described, comprising, means for taking a fractional portion of the -material, an accumulating measuring element therefor adapted to receive the material, means for discharging the accumulations, and a recording element on said measuring element.

In testimony whereof We aflix our signatures this 17th day of December, 1920.

CLARENCE G. DRESSER. FLOYD s. YOUTSEY. I

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