US2943478A

US2943478A - Sample removing apparatus

Info

Publication number: US2943478A
Application number: US514946A
Authority: US
Inventors: Carl W Brabender; William R Coyne
Original assignee: Pillsbury Co
Current assignee: Pillsbury Co
Priority date: 1955-06-13
Filing date: 1955-06-13
Publication date: 1960-07-05
Anticipated expiration: 1977-07-05

Description

July 5, 1960 c. w. BRABENDER ErAL 2,943,478

SAMPLE REMOVING APPARATUS 5 Sheets-Sheet 1 Filed June 13, 1955 1960 c. w. BRABENDER ETAL 2,943,478

SAMPLE REMOVING APPARATUS 5 Sheets-Sheet 2 Filed June 13, 1955 F/a. Z

C221 MAL/Aw R 60 W July 5, 1960 w. BRABENDER ETAL 2,943,478

SAMPLE REMOVING APPARATUS Filed June 13, 1955 5 Sheets-Sheet 3 H7701? Eff y 1950 c. w. BRABENDER ETAL 2,943,478

SAMPLE REMOVING APPARATUS 5 sheets-sheet 5 Filed June 13, 1955 flaw-wraps 5 M m 5 0 flaw A. m Z ML United States Patent SAMPLE REMQVING APPARATUS Carl W. Brabender, Wayzata, and William R. Coyne,

Minneapolis, Minn., assignorsto The Pillsbury Company, a corporation of, Delaware 7 Filed June 13, 1955, Ser. No. 514,946

Claims. (CI. 73-76) This invention relates to apparatus for determining the moisture content of pulverulent or granular materials. More particularly, it relates to apparatus for effectively removing the dried sample, the moisture content of which has been determined, from the sample pan to permit a fresh sample to be deposited within the sample pan.

In makingmoisture content determinations, the conventional method of removing the dried material of .the previous determination from the sample pan is to manually empty the pan and clean it to insure that no particles of the previous determination remain therein. This procedure requires a substantial amount of time and effort and constitutes an important part ofthe time involved in rials such as flour.

A more specific object is to provide novel and improved apparatus which will obviate the need for manually emptying sample pans at the end of each moisture content determination.

- Another object is to provide novel and improved apparatus for use in conjunction with moisture determination devices which will eliminate the need for manually emptying the sample pan after each determination and will, at the same time, effectively clean the pan.

Another object is to provide novel and improved apparatus for use in conjunction with moisture content determining devices which will automatically and efiectively empty and clean the sample pan after each moisture content determination and which will do this without removing the sample pan from the scale.

These and other objects and advantages of the invention will more fully appear from the following description made in connection with the accompanying drawings, wherein like reference characters refer 'to the. same or similar parts throughout the several views, and in which:

Fig. 1 is a side elevational view of one embodiment of our invention;

Fig. 2 is a plan view of the same;

Fig. 3 is a rear elevational view of'the same embodiment of our invention; a

Fig. 4 is a fragmentary side elevational view ofth moisture content determining device on an enlarged scale viewed from the side opposite to that of Fig. l;

Fig. 5 is a fragmentary rear elevational view of the drying and sample-withdrawing mechanism of the moisture content determining device taken on an enlarged scale;

Fig. 6 is a sectional view taken along line 66 of Fig.2;"

Fatented July 5, 1960 ree Fig. 7 is a plan view of the sample pan and pan driving support of the device with portions of the former broken away to show the latter, the view being taken on an enlarged scale;

Fig. 8 is a vertical sectional view taken along line 8 -8, of Fig. 7;

v Fig. 9 is a vertical sectional view taken along line 99 of Fig. 2; V

Fig. 10 is a vertical sectional view taken along line 10--10 of Fig. 2;

Fig. 11 is a side elevational view of the cam series connected with the timing motor, the view being shown on an enlarged scale;

Fig. 12 is a diagrammatic view of the beam balance and recording mechanism showing the relation therewith to the other pan support; I

. Fig. 13 is a plan view of the electrovane at the end of the beam balance, as shown in Fig. 12; and

Fig. 14 is a wiring diagram showing the electrical lines connecting the various operating elements of the moisture content determining device.

One embodiment of our invention, as shown in Figs. 1-14, may include a frame indicated generally as F. Mounted upon this frame F at one side thereof is an electric motor 15 which drives, by means of a chain extends across the entire width of the stack 18 and outminal 24a.

tioned directly below the discharge terminals 17a and wardly therefrom. The auger conveyor 17 has a discharge terminal 17a and the trough 19 has an associated discharge terminal 19a. Theauger conveyor 17 when driven by the motor 15 and chain drive 16, rotates in such a direction as to convey material toward these discharge terminals. The conveyor 17 and trough 19 together form a sampling mechanism for withdrawing representative samples from the stack 18.

Mounted on a portion of the frame F and extending upwardly therefrom is a foot or support 20. Carried by the upper portion of this support 20 is a bracket 21; and, journaled in this bracket is a pivot shaft 22 to which is secured a disc 23 for pivotal movement therewith about the longitudinal axis of the shaft 22. Mounted on,

the disc 23 for pivotal movement therewith is a tilting chute 24 which can be tilted about the axis of the shaft 22 with the disc 23 so that its discharging terminal 24a which extends toward the front of the machine may be in loading position relative to the sample pan, as best shown in Figs. 1 and 4, or in raised position as shown in broken lines in Fig. l. The discharging end 24a of the chute 24 is open, as is its upper end portion 24b, so that flour may pass through either end at will, assuming its passage is not arrested by other elements as to be hereinafter described with respect to the discharge ter- The medial portion of the chute 24 is posi- 19a of the auger conveyor 17 and trough 19, respectively, so as to receive all of the flour conveyed by the conveyor 17.

Mounted on the frame F in position to receive flour from the rear end portion 24b of the tilting chute 24 when that end portion is swung downwardly, as shown in broken lines in Fig. 1, is a salvage conduit 25, the upper end of which is open. This salvage conduit 25 returns the flour received from the rear end portion 24b of the chute 24 back into the main stream of flour which has.

passed the moisture determining machine. I

Mounted on the mounting bracket 21 is a chutevtilting motor 26 which by a gear 27 drives vertically a tilting rod 28 which has gear teeth 28a formed on one side" 1 3 thereof and engaging and cooperating with the gear 27. The-upperend of therod 28-is pivotally connected to the chute 24 so as to tilt the chute as the rod 28 is driven upwardly or downwardly by the motor 26. This can best be=seen-in 4. The motor 26 is 'a reversible motor and is controlled in a manner to be hereinafter described.

Mounted 'onthe-disc 23 directly above the'medial-portions of the chute 24 is a pulsating vibrator 29"which carries a gatesupporting arm 30 extending forwardly therefrom above the chute. At the forward end of the arm 30'is a depending gate member 31 which extends into the discharge terminal portion 24a of the chute. A-catch 32extends upwardly from the arm 30in position to be engaged by apivotable latch element 33, as shown in' Fig. 4. 'To this 'latch-elementB-Q there is conne'cted a rearWardly-extending camming lever 34 which swings with the latch element.

- -Also secured to the chute 24 is another electrical pulsating-vibrator '35 whichis controlled in a manner to be hereinafter described. A switch box housing H houses an upper and a

lower limit switch

23a and 23b for the chute 24 and a pin 23c extends'laterally from the disc 23 into the interior-of-the housing to engage these switches as 'the-chute pivots.

Mounted adjacent to the chute 24 is a drying chamber 36. The discharge terminal portion 24a of the chute extends'through one of the walls of the chamber and is freeto tilt upwardly therewithin. A sample pan 37 which extends upwardly through'an opening in the bottom of the chamber -36,-as best shown in *Fig. 5, is supportedin material-receiving positionrelative to the discharge terminal-portion 24'a'of the chute. This pan '37 is supported bye pan driver 38which is supported by "ahollow drive shaft 38aand is journaledon a mounting plate or tilting beam 39 and drivenby a chain drive 40' which in turn is driven by 'a pan driving electric motor 41. This can best beseen in Figs.- and -7. The under side of the pan 37 carries a depending centering or positioning pin 37a and aradially-spaced depending drive pin 37b. The inside of the cup-shaped pan driver 38 has a plurality of driving dogs 38b one of whichengages the drive pin 37b ofthe pan'to drive thesame. Extending upwardly through the hollow drive shaft 38a is a pan support rod 42 with a pan support 43 at itsupper end, the rod 42 being a part of a pan-weighing mechanism to'behereinafter described. The pan support 43 has a central recess within which the centering pin 37a extends, but the bottom of the pan 37 norm-ally just clears the upper surface of the pan support 43 "The mounting plate 3? is pivotally supported by a pair of spaced depending

journal plates

44 and 45 which extend "downwardly from the chamber 36, as best shown in Fig. 4. An inverted channel member 46 is secured to the underside of the plate 39 and a pressure plate 47 extends downwardly from the medial portions thereof. Mounted-on the side of the journal plate 44 is an electric beam'tilting motor 48 which has a driving shaft 49 extending over to the journal plate 45 and carrying a cam 50'which engagesthe pressure plate 47 as it rotates with the driving shaft 49. This electric motor 48 is controlled in a'manner-to be hereinafter describedand operates to tiltthe mounting-plate 39 sothat it functions as a tilting beam. A weight 51 is secured to the end of the tilting beam 39 opposite to that carrying the pan driver 38 so as to constantly urge the latter upwardly toward panengaging positon, as shown in Fig. 5. 'The'sha-ft 49 also carries a second cam 52 which normally holds a-microswitch -53 in closed position but releases it toopen position-when a recess on the'cam isopposite the switch as shown'inFig. '5. 'The microswitch 53 is positioned within the circuit to the beam-tilting motor 48 so as to interrupt the'current thereto when the cam'dt'l reaches the position shown in Fig. 5.

*Secured'to the weighted end portion of the tilting beam 39 is a chain 54 which extends upwardly and is secured to one end of a pivot lever 55, the other end of which carries a weight 56 and the medial portion of which is mounted upon a pivot shaft 57, as best shown in Fig. 1. The pivot shaft 57 extends in substantially the same direction as the tilting beam 39 and is journaled in the side wall of the drying chamber 36. An infrared lamp 58 is secured to the oth'eiiendso'f the shaft 57 and swings therewith when the shaft pivots, about .its longitudinal axis. The lamp '58, whenhang'ing straight downwardly from the shaft 57, is positioned-directlyabovethesample pan 37 and directed thereinto.

Mounted upon the floor of the dryingchamber I36 and extending upwardly therefrom is a post 59 upon which is pivoted a bar 60 carryinga weight :61 and a stirring rod 62 which extends downwardly into .thepan 37 at its side walls and then toward and beyond the center of the pan and along its bottom. At the other end of the bar 60 and on the opposite side of the post 59 is an upwardly extending lever arm 63 which is positioned in the path of the swinging movement of the lamp 58 as best shown in Fig. 4, so that when the lamp 58 is swung sidewise away from the pan 37, the stirring rod -62 is also lifted to an aloft position out of the confines of the pan.

Mounted on the frame F below the drying chamber 36 is a weighing mechanism M. This mechanism M is preferablyof the type shown in the United States Letters Patent 'No. 2,047,765, issued to Carl W. Brabender, dated July 14, 1936. The critical portions thereof are shown diagrammatically in .Fig. 12 and include a'bearn balance 64 pivoting about a fulcrum 65 and supporting by one of its end portions, the pan support rod 42 which extends upwardly through the floor of the drying chamber 36. The other end portion carries 'a panel '66 which is positioned to pass between an electrovane 67 as that end portion is raised and also carries a panel 68 which is positioned to pass between an electrovane 69 when that end portion is raised still farther. The extreme end portion 70 of the beam balance 64 is positioned so that when an electrovane 71 is'lowered,'that end portion will pass through it and actuate the same just as the panels 66 and '68 actuate the

electrovanes

67 and 69 respec-' tively when they extend between opposite portions of each. These electrovanes are manufactured by the 'Brown Division, Philadelphia, Pennsylvania, of Minneapolis Honeywell Regulator Co., "Minneapolis, Minnesota, and may be purchased from that company :under'the identification of part'No. 353,848-1. They include a pair of spaced detecting coils which may be shielded from each other by passing a vane therebetween. When the vane is not shielding the detecting coils from each other, the electronic circuit de-energizes the relay of the unit and a circuit is closed to accomplish the desired action as hereinafter defined. The scale mechanism M maybe purchased from the Brabender Corporation, Rochelle Park, New Jersey, and is identified by that company merely as a Brabender scale.

The electrovane 71 is carried by a gear mechanism 72 which is threadably mounted for vertical movement on a vertical threaded shaft "73, which is driven by a motor 74. A second threaded shaft 75 extends vertically through the gear mechanism72 and threadablyengages the same so that vertical movement of the gear mechanism 72 causes rotation of the shaft 75 about its longitudinal axis. A gear reduction mechanism '76 conmeets the upper end of the shaft 75 with a swingable recording pen 77 which inks the record of the extent of its swing upon a chart 78. This chart 78 is constructed, graduated and correlated with the extent of swing of the pen 77 so as to give a direct reading of the moisture content of the sample, the sample having been of a predetermined weight prior to having been dried. A time stamp mechanism '79 operated by a solenoid .80.records the time upon the chart 78 each time a recording is made.

Mounted upon and extending through one wall of the motor 97 and stops the latter.

drying chamber 36 is a telescoping withdrawing or discharge chute D having a fixed upper portion 81 and a relatively movable portion 82, the latter of which has longitudinally arranged gear elements 83 on its outer surface cooperating with a drive gear 84 which in turn is driven by a reversible motor 85. When the gear 84 is driven, the lower portion 82 moves telescopically relative to the upper portion 81. A spacer element 86 extends downwardly from the lower end of the movable portion 82. A trip arm 87 extends laterally from the movable portion 82 and into a slot 88 formed by a housing 89 which covers an upper limit switch 90 and a lower limit switch 91. The chute is arranged so that the spacer element and the lower end portion 8 2 will extend within the confines of the pan 37 when at its lowermost position. A brush 92 is carried by the lower end of the portion 82 and this brush extends into the pan 37 and brushes the peripheral portions of the bottom of the pan to dislodge any particularly securely adhering particles of flour as the pan rotates.

The upper portion 81 is connected by a conduit 93 to a cyclone 94 which discharges the collected material into a collector 95. The upper end of the cyclone is connected to a suction creating mechanism 96 such as is used in a vacuum cleaner.

Associated with the various motors, relays, and moving parts is a timer controlled camming mechanism C which is best shown in Fig. 11 and which is electrically connected with the various parts as best shown in Fig. 14. For the sake of reference there is employed a timer motor 97 which drives a main cam-carrying shaft 98. This shaft carries a number of cams indicated as 99, 100, 101, 102, 103, 104, 105 and 106. Each of these cams has a

switch

107, 108, 109, 1-10, 111, 112, 113 and 114 respectively associated therewith and the switches are connected electrically as shown in Fig. 14. Each of these cams has at least one recess formed in its camrning surface to release its switch during a part of its rotation with the shaft 98 and the remainder of its camming surfaces cam the switches inwardly. Some of these cams have more than one recess and some of these switches are three-way switches as will be described in more detail hereinafter.

Cam 100 actuates switch 108 which is electrically connected to a solenoid valve 118 which controls the passage of air through an air conduit 119 which is connected to a source of compressed air (not shown). The conduit 119 terminates within the tilting chute 24 and is directed so as to dislodge particles of the previous sample which may have stuck within the chute.

At the start of one of the cycles, the timer motor 97 is rotated and it turns the shaft 98 until the recess of cam 99 is opposite its switch member 107 which permits the switch member to move to closed position and thereby energize the two l0-second time delay relays 115, 116 shown only in the wiring diagram, Fig. 14, and the two-minute time delay relay 117, also shown only in Fig. 14. This switch member 107 as it closes, establishes a. current also to the auger conveyor motor 15 and to the vibrator 35 on the chute 24. When these two s econd relays close, they complete a circuit to the motor 26 which tilts the tiltable chute 24. As this motor 26 commences to tilt the chute 24, the tilting action swings an arm or pin 230 which releases a microswitch 23a which in turn breaks the circuit leading to the timing bythe chute tilting motor 26 when the current is closed thereto by the closing of the ten-second time delay relays 115, 116. As the chute 24 reaches the pan filling position, the microswitch 23b at the upper end of the path of the pin 230 is actuated to out 01f the tilting motor 26 and thereby cease the tilting action. The vibrator 35 continues to operate until 9% grams of flour have been deposited within the sample pan 37, and during that time the flour is fed into the feed chute 24 by the auger The chute 24 is tilted conveyor 17 and descends, as a result of the vibration, down the tilted chute and into the pan.

If the chute 24 has not returned to tipped-up position within two minutes, the two-minute time delay relays 117 are closed and establish a circuit to awarning signal (not shown) which will be sounded. In other words, the sample should be completely delivered within atwominute period into the confines of the sample pan 37, and if this is not the case, something has operated improperly and the mill supervisor will be apprised of that situation.

When the sample pan 37 has received 9% grams of flour, electrovane 67 is actuated by the tilting of the scale beam 64. This tilting, of course, is caused by the weight of the flour deposited into the pan ,37 so that the vane 66 is introduced between the spaced coils of the electrovane 67. This electrovane closes a current to the pulsating vibrator 29 which closes the gate 31 on the chute 24 and permits the latch 33 to engage the catch 32 and lock the gate in position. This electrovane 67 also, at the same time, cuts oif the current to the auger conveyor motor 15 so that it ceases to withdraw samples from the stack 18. At the same time, this electrovane 67 breaks the current to the pulsating vibrator 35 and thereafter only a dribble feed of the pulverulent material (created by material slipping past gate 31 as a result of the vibrations of vibrator 29) enters into the pan 37 until an additional /2 gram has been added to bring the weight of the sample within the pan to the 10 gram level. Of course, the entire mechanism may be adjusted so as to weigh out a 5 gram sample and make a determination of that weight of the pulverulent material. The weight of the sample causes the scale beam 64 to tilt farther so as to cause the vane 68 to pass between the spaced coils of the electrovane 69. This second electrovane 69 cuts off the current to the vibrator 29 and at the same time establishes a current to thechute tilting motor 15, which in turn tilts the discharge terminal 24a of the chute 24 back to raised position. This electrovane 69 also cuts the current to the two-minute delay relay 117 so that the warning signal will not be sounded.

As the chute reaches the end of its upward tilting movement, the lower microswitch 23a associated there with is closed by the actuating arm 230 to close the circuit to the timer motor 97 and commence it to again rotate the shaft 98 and the cam carried thereby. The closing of the lower microswitch 23a also cuts off the current to the tilting motor 26. Thereafter the timing motor 97 continues to operate continuously for the remainder of the cycle. As the discharge terminal 24a of the tilting chute 24 tilts upwardly, the flour deposited in the chute 24 and prevented from being discharged therefrom by the gate 31 slides rearwardly and is discharged into the salvage conduit 25 from the rear end of the chute. This insures that none of the flour of the previous sampling is included with that of a subsequent sampling. At the same time, the latch 33 is cammed to released position at the end of the tilting action. The purpose of the latch 33 is to prevent excess flour from dropping into the pan 37 when the chute 24 starts to tilt upwardly at the end of the sample discharging operation.

The timing motor 97 continues to turn the cams 99 106 until the recess on the

cams

104 and 106 permits their associated

switches

112 and 114 to close. Cam 104 controls two motors, one which rotates the pan (the pan rotating motor 41) and the other 48 which tilts thepan carrying beam. Both of these motors are actuated when the switch 112 associated with the recess of earn 104 closes.

switch is forced to open position, the lamp is no longer energized. When the beam 39 is tilted,the lamp 58 is also swung to drying position above the beam 37. The,

Cam 106 controls the current to the infrared cam '50 mounted on the "driving shaft 49 of the beam tilting motor 48 beats against'the pressure plate 47 which depends from the beam 39. 'When this-pressure plate 47"is actuated by the beam tilting motor cam 50, the beam 394s tilted to withdraw the chain 54 downwardly, which in turn causes the shaft 57 carrying the lamp -58 to pivot about its longitudinal axis and into drying position relative to the Sample pan 37. v

I It will be recalled that the pan rotating motor '41 is mounted on the beam 39 and is connected with a chain drive 40 to the pan driver 48 which is a cup-shaped element having four pan driving dogs '48 thereon. Prior to the tilting of the beam 39-, the pan 3-7 rests upon the pan support 33 of the scale, this pan support being a small disc with a central recess. The depending positioningp'in 37a of the pan extends downwardly into the recess 'of the pan support 43, and the depending drive pin 37b is engaged by the pan driving dogs 38b to rotate the pan. As the beam tilts, the pan driver 38 engages and lifts the pan 37 oil the pan support 43 and rotates the same about a vertical axis. The infrared lamp 58 is directed into the confines of the sample pan 37 as a result of swinging to drying position. The stirring rod 62 extends into the sample and the relative rotation of the sample pan causes the rod to continuously change the upper surface of the sample which is presented to the heat and drying action of the lamp 58. In this manner a much more relatively intense heat may be used,

and since the infrared lamp has such penetrating qualities the combined action results in a rapid drying 'process. So long as the upper level of the sample is continuously changed, and there is moisture remaining in the sample, there'is no danger of scorching which would cause inaccurate determinations. By continuously changing the upper surface of the sample, the drying opera tion is reduced to a matter of a very short period. The drying period continues until the timer motor '48 has turned the cams 1M and 106 sufficiently far to initiate action on the part of the beam tilting motor, as will be hereinafter described.

As the tiltingbeam 39 reaches the end of its tilting action, (immediately prior to the drying operation) a cam 52 on the tilting motor 48 engages a microswitch 53 which breaks the current to the beam tilting meter 48itself, and this motor remains idle for the entire drying period until, at the end of that period, when the

cams

104 and 106 have been driven far enough by the timing motor 97 so that the recess on cam NM terminate's. At that point, the associated switch 112, which is -a three-way switch, is pressed inwardly to close a separate circuit to the tilting motor 48, and cam 106 opens its associated switch 114 and thereby cuts off the current to the lamp 58. The tilting motor 48 then continues to operate and its pressure plate engaging cam 50 rotates, thereby permitting the pressure plate 47 to retract and permit the tilting beam 39 to commence to tilt back to its original position. When the tilting beam reaches its original position, the cam 52 on the beam tilting motor 48 releases the mic'roswit'ch 53 which breaks the current to the beam tilting motor 48. As the beam tilts back, the pan driver 38 is lowered and the 37 is again engaged by the pan support 43 of the scale mechanism M. In so doing, the chain 54 to the lamp carrying shaft 57 is released and the weight thereon causes the shaft to pivot about its longitudinal axis, thereby swinging the lamp to one side to non-drying position.

When the tilting beam 33 is permitted to tilt back and the chain 54 connecting the beam to the'lamp carry ing shaft 57 permits the weighted shaft to pivot to swing the lamp sidewi'se, the lamp engages the lever arm 63 of the stirring mechanism and causes the stirrer 62 to beswung upwardly and laterally away from the pan.

The return of the pan 37 'to the pan support 43 of the scale causes the scale to automatically register the weight of the dried sample and the interpolation of the loss of weight is displayed in the two places, namely upon the continuous chart 78 through the recording mechanism which is actuated by the third electrovane .71 by the beam of'the scale, and also at a reading window on the scale. At the end of the drying action and return of the beam 39, cam 111 cuts in a switch which energizes electrovane 71 which, when entered by the beam '64, act-uates the motor 74 which drives shaft 73. The rotation of the shaft 73 causes the gear mechanism 72 to lower until the extreme end 70 of the beam balance 64 passes between the coils of the 'electrovane to energize the same. When electrovane 71 is energized, it cuts off the current to the motor 74 so that the gear mechanism is arrested at that position. The downward movement of the gear mechanism 72 causes the shaft 75 to rotate about its longitudinal axis and, through the gear reduction 76, to swing the recording pen 7'7 laterally the appropriate distance to indicate accurately upon the chart 78, the moisture content of the sample. When the tilting beam has returned to its original position, the current to the infrared lamp-58 is shut off by cam 106 moving its associated switch 114 to open position.

After the recording has been completed ashereinbefore described, the timing motor 97 which is continuing to operate, will move cam 107 to energize a time stamp '79 for the chart 7%. Thus the time of the deermi-nation will be stamped upon the chart opposite the recording made by the recording pen 77. There after cams N2, 11% and "1M come in at approximately the same time. Actually cam 1W. moves so as to permit its associated switch 112 to close first to energize the beam tilting motor 43 and the pan rotating motor 41. This motor 41 tilts the beam until stopped by its second cam 52 and limit switch 53, and the pan is lifted by the pan driver 38 and rotated thereby. Thereafter cam 103 permits its associated switch 111 to close and this energizes the vacuum chute moving motor $5 which is connected by gear mechanism 33, 84 to the vacuum chute D to lower its lower end 82 to a position immediately above the pan 37 carried by the scale. The limit switches 91), 91 at both ends of the path of movement of the chute prevent the chute from moving downwardly or upwardly too far. When the chute reaches a position immediately above the pan so that its spacer element 86 engages the bottom of the pan and its brush 92 extends into the confines of the pan against the bottorn thereof, the downward movement of the lower par't 82 of the chute D will be stopped because the microswitch 91 will cut olf the vacuum chute moving motor 85. Immediately thereafter cam 102 permits its associated switch lit? to close to energize the vacuum inducing mechanism 96 which causes the vacuum chute D to draw the material upwardly out of the pan. As the pan rotates, the brush 92 dislodges all fine particles from the bottom of the pan and these are sucked upwardly through the vacuum chute D.

After the material'has been drawn out of the pan, cam lilZ cuts out the vacuum mechanism 96 and thereafter cam Th3 cuts in the reversible vacuum chute moving motor so that the lower portion $2 of the vacuum chute D is moved upwardly until the limit switch E at the upper end of the path of movement is engaged, whereby the current to the vacuum chute moving motor 35 is again out off. Thereafter the second recess of cam i614 reaches its end and presses inwardly the switch 112, which is a three-way switch, and thereby closes a separate circuit to the beam tilting motor 43 to thereby tilt the beam back to the position where the pan rests upon the pan support 43 of the scale. This switch 112 at the same time cuts off the current to the pan rotating motor 41. At the end of the tilting action of the beam, the cam 52 on the \heam tilting motor 48 cuts out the current to that motor.

Thereafter cam 100 closes the current to a solenoid valve 118 which opens an air conduit 119 connected to a source of compressed air (not shown). The conduit terminates within the tilting chute as shown and is directed so as to dislodge particles of the previous sample which may have stuck within the chute. The timing motor 97 continues to rotate the cams until cam 100 cuts off the current to the solenoid valve and cam 99 has its recess opposite its associated switch 107. it again energizes all of the timing relays 115-417 and the entire operation commences to repeat itself.

"Thus it can be seen that we have provided novel apparatus for removing the sample from a sample pan at the termination of a moisture content determination, moreover, the apparatus removes the sample from the pan automatically without manual manipulation or supervision. It quickly and efficiently withdraws the pan and cleans it so as to avoid possible error in ensuing determinations. It disposes of the dried sample without any mess or time-consuming procedures and without removing the pan from the scale. The entire operation is automatic and thus effects a substantial saving in time, effort and cost.

Portions of the subject matter disclosed in the present application are claimed in companion applications Serial Numbers 514,945 and 514,947 filed on even date herewith.

It will, of course, .be understood that various changes may be made in the forms, details, arrangement and proportions of the various parts without departing from the scope of our invention.

What is claimed is:

1. A device for removing samples from the sample pan of moisture-content determining apparatus after the determination has been completed, said device comprising a conduit having an intake terminal and a discharge terminal, mounting structure movably supporting said conduit for movement to bring its intake terminal from a non-adjacent position to a position in close proximity to and above the sample pan and back again, time sensitive control mechanism connected to said conduit and constructed and arranged to be connected with such moisture determining apparatus for automatically moving the intake terminal of said conduit into close proximity and above said sample pan at the close of each determination, means for inducing a negative pressure Within said conduit to cause the contents of the sample pan to be withdrawn therefrom and to pass through said conduit when its intake terminal is swung to such position.

2. In moisture-content determining apparatus, mechanism for weighing and discarding samples of material comprising a sample pan, a stationary frame, a balance fixedly mounted on said frame and supporting said sample pan and indicating the weight of the same and its contents, a conduit having an intake terminal and a discharge terminal, mounting structure movably supporting said conduit for movement of its intake terminal from a position non-adjacent to said sample pan to a position above and adjacent to said sample pan and vice versa, time regulated control mechanism connected to said conduit and with said balance for automatically moving the intake terminal of said conduit into close proximity and above said sample pan at the close of each determination, and means for inducing a negative pressure within said conduit and thereby causing the contents of said sample pan to be withdrawn therefrom and to pass through said conduit and discharged therefrom when its intake terminal is swung to such position.

3. A device for removing samples from the sample pan of moisture content deter-mining apparatus after the determination has been completed, said device comprising a conduit having an intake terminal and a discharge terminal, mounting structure movably supporting said conduit for movement to bring its intake terminal from a non-adjacent position to a position in close proximity to and above the sample pan and back again, time regulated control mechanism connected to said conduit and the moisture content determining apparatus for automatically moving the intake terminal of the same to said position and back again at the close of each determination, and means for inducing a negative pressure within said conduit to cause the contents of the sample pan to be withdrawn therefrom and to pass through said conduit when its intake terminal is swung to such position.

4. In moisture content determining apparatus, mechanism for weighing and discarding samples of material comprising a sample pan, a laterally immovable balance supporting said sample pan and indicating the weight of the same and its contents, a conduit having an intake terminal and a discharge terminal, mounting structure movably supporting said conduit for movement of its intake terminal from a position non-adjacent to said sampie pan to a position above and adjacent to said sample pan and back again, time regulated control mechanism connected to said conduit and with said balance tor automatically moving said conduit from said non-adjacent position to said adjacent position and back again, and means for inducing a negative pressure within said conduit and thereby causing the contents of said sample pan to be withdrawn therefrom and to pass through said conduit and discharged therefrom when its intake terminal is swung to such position.

5. in moisture content determining apparatus, mechanism for weighing and discarding samples of material, comprising a sample pan, a balance supporting said sample pan and indicating the weight of the same and its contents, suction type Withdrawing mechanism movably mounted adjacent said sample pan for movement from a position non-adjacent to said sample pan to a position above and adjacent to said sample pan and back again, and time regulated control mechanism connected to said conduit and with said balance for automatically moving said suction type Withdrawing mechanism from said nonadjacent poistion to said adjacent position and back again at the end of each determination.

References flied in the file of this patent UNITED STATES PATENTS 1,048,446 Curry Dec. 24, 1912 1,081,723 Curry Dec. 16, 1913 2,162,019 Johnson June 13, 1939 2,622,438 Campbell Dec. 23, 1952 2,643,160 Zeig June 23, 1953 FOREIGN PATENTS 702,578 Great Britain Jan. 20, 1954