US3293907A

US3293907A - Apparatus for determining the moisture content of grain, or the like

Info

Publication number: US3293907A
Application number: US261738A
Authority: US
Inventors: Schnatz Gustav; Richter Lothar
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-02-28
Filing date: 1963-02-28
Publication date: 1966-12-27
Anticipated expiration: 1983-12-27
Also published as: GB1004120A; DE1234052B; CH401538A; NL289538A

Description

Dec. 27, 1966 G. SCHNATZ ETAL APPARATUS FOR DETERMINING THE MOISTURE CONTENT OF GRAIN, OR THE LIKE Filed Feb. 28, 1963 l IIIIIIIIIIJIIIIIUIJ 7. 7' INVENTORS Gusmv SCHNATZMCI L THAR RlcHTER Men 4710 Fri 25 United States Patent 3,293,907 APPARATUS FER DETERMINING THE MQESTURE QtlNTENT @F GRAIN, UR THE LEKE Gustav Schnatz, 11 frchone Aussicht, Maschen, Hat-burg,

Germany, and Lothar Richter, l9 Winsener Landstrasse, Fieestedt, Harhnrg, Germany Fiied Feb. 28, 1363, Ser. No. 261,738 Ciaims priority, appiication Germany, Feb. 28, 1962, Sch 31,058 6 Claims. (Ci. 73-73) This invention relates to rotary testing apparatus for cyclically determining the moisture content of grain, or the like, based on a sample which is ground and introduced into a measuring container and compressed therein, the measuring container comprising means for measuring the electrical resistance and the temperature of the sample.

When drying and storing grain, or the like, it is necessary to determine its moisture content either at regular intervals, or continuously.

Generally the above mentioned measurements are required when grain, or'sirnilar material, is delivered for storage, since the moisture content is a controlling factor with regard to storage time and price. If these measurements show a too high moisture content, the grain is 'fed to a dryer whereupon, after drying, the moisture content must be determined again. In conventional practice, the samples are manually removed from a stream of grain at timed intervals and are then measured in a laboratory. However, from the time of taking the sample until the measurement results are known, a certain time is lost depending on various factors and, during this time, grain having an objectionable moisture content is delivered to the storage facility or to the dryer. Moreover, samples are usually removed from a large quantity or batch of grain and practice has shown that such samples do not always reflect the actual moisture content of the entire batch although the batch is well mixed. Since the samples are taken manually generally every half hour there is no assurance that the representative moisture content for all of the grain is actualy measured.

Therefore it is an object of the invention to provide a rotary cyclically operative apparatus for repeatedly determining the moisture content of grain, and which will determine the moisture content of a continuously conveyed fiow of grain at very short time intervals, or nearly continuously.

Briefly, the measurement container and grinding means are arranged for rotation as a unit about a substantially horizontal axis and with their inner chambers communicating with each other in such a way that the sample will flow from the grinding means into the measuring container and vice versa by gravitational action.

Preferably this is accomplished in such a manner, that the measuring container includes two openings, each being separately closable by a suitably controlled slide, one of the openings communicating with the inner chamber of the grinding means while the other opening forms an inlet for the sample to be measured. By means of this arrangement, a sample amount may be removed from a flow of grain without manual operation and may be introduced into the chamber of the grinding means from where it is automatically passed into the measuring container by gravitational flow after the grinding is finished and the moisture content is measured using the measuring electrodes provided within the container. Because the measuring container is eccentrically mounted for rotation with the grinding means, all of the movements of the sample required for the measuring are produced by gravity and may advantageously be controlled in accordance with the angular position of the measuring con- 3,293,97 Patented Dec. 27, 1966 tainer and the grinding means, so that the measuring apparatus will operate automatically. Due to this it is possible to install the apparatus according to the inven tion directly at the conveyor, or mount it thereon respectively, whereby transportation of the sample to the laboratory is omitted. An etfectively continuous measurement, or a measurement repeated at very short time intervals of a few minutes is thus made possible so that between succesive measurements only a small amount of material will pass the sampling bone. When dryers are used, the measured values of moisture content may be translated into electrical control impulses for regulating the action of the dryer.

In the drawings:

FIG. 1 is a schematic sectional view of measuring apparatus embodying the invention; and

FIG. 2 is an enlarged fragmentary sectional view showing the measuring container and the grinding means of the apparatus according to the invention.

The measuring apparatus comprises essentially two important members, the grinding means 1 and a measurement container 2. The interior chambers of the grinding means and of the measuring container are connected together so that a sample may pass from the measuring container to the grinding means and vice versa. The measuring container 2 is provided with two laterally spaced resistance measuring electrodes 3 and temperature measuring means 4 which may be a thermometer, a thermocouple element, or the like. The measuring electrodes 3 as well as the temperature measuring means 4 are connected to suitable indicating or other utilization means (not shown).

The measurement container 2 and the inner chamber of the grinding means 1 may be shut off from each other by a radially inner cam-actuated slide 5. An inlet opening 6 of the measurement container 2 may be shut off from the interior of the container by a radially outer cam-actuated slide 7. Once during each revolution of the apparatus, and when the measurement container is upwardly directed, the inlet opening 6 is brought into axial alignment or register with an inlet tunnel or receiver 8 for the sample, whereby a sample of predetermined volume may be metered and passed via the container 2 into the grinding means 1 with the

slides

5 and 7 both open.

After the sample arrives within the grinding means 1, it will start to operate. As shown, the grinding means may operate continuously independently of the presence of material to be ground. During grinding, the upper slide 7 is closed so that the sample is ground under conditions which exclude air and prevent the escape of moisture. The closure of the slide 7 is suitably achieved by the fact that the grinding means together with the measuring container are pivoted on a hollow counterclockwise rotating shaft 9 which extends axially at the center of a stationary cylindrical drum it) so that the slide 7 engages a fixed arcuately extending slide-actuating cam 11 at the angular position A.

Details of the construction of the cam 11 and cooperating slide 7 have been omitted for simplicity of illustration. The cooperation is such, however, that the slide 7 is positively actuated by the cam 11 both for opening and closing, the slide 7 being continuously closed throughout the arcuate extent of the cam 11 from angular position A proceeding counterclockwise to position E and open from angular position E proceeding counterclockwise to position A. The cam 11 is thus a doubleacting cam. Any conventional arrangement may be used, such as a cam-follower roller guided between the lateral walls of a camming slot, a biasing spring ar' rangement for open-ing the slide, a slotted cam follower which is positively actuated by a fixed camming lip engaged in the slot, or any other convenient means for causing the opening and closing sequence for the slide 7 as described above. Because of their manner of operation, the slide controlling cams are hereinatfer referred to, for convenience, as double-acting cams.

Thereafter, the grinding means with the measuring container continues to rotate counterclockwise to the position B where the drive of the grinding means is preferably switched oft by cam-actuated means (not shown). After stoppage of the grinding means 1 and further counter-clockwise rotation of the shaft 9, the position of the measurement container 2 changes relative to the inner chamber of the grinding means 1, whereby the ground material contained in the grinding means fiows by gravity into the measuring container 2. In the position C the entire sample has been transferred to the measurement container 2 and the slide 5 is closed by a fixed double-acting arcuate control cam 12. Thus, the sample is confined in the temperature and moisture measurement container 2 and the measuring procedure may take place.

The measuring procedure also includes the compression of the ground sample of the goods which is achieved by the invention in such a way that a telescopically arranged spring loaded coaxial extension 13 of the measuring container 2 is yieldingly urged axially outwardly of the measuring container. This tubular extension 13 carries the outer slide 7 so that the volume of the measurement chamber of the measuring container 2 may be decreased and the sample compressed. The compressive movement of the telescoping extension 13 is obtained in a simple manner by engagement of a shoulder of extension 13 with a fixed control cam 14. After the compression is completed at position D, the electrical measuring electrodes and the temperature measuring means are utilized and the measurements are made while the rotating movement of the shaft 9 carrying the grinding means and the measuring container is momentarily interrupted. This interruption is suitably timed and is terminated after the measurements are completed. Thereupon shaft 9 resumes its rotation and the compression of the sample is discontinued by disengagement of the extension 13 from the control cam 14. This abrupt release causes loosening of the sample compressed in the measuring container whereupon, at the position E, the

slides

5 and 7 are opened by the double-acting

cams

12 and 11, respectively, and compressed air is blown into the inner chamber of the grinding means 1 via the duct 15. Thereby the spent sample is blown out and drops downwardly through the inlet opening 6 and the outlet opening 16 in drum into a storage bin (not shown). Simultaneously, the grinding means may start operating again to facilitate by its movement the pneumatic discharge of the measured sample. At the position F the supply of compressed air is shut off and the measuring container and the grinding means return after further rotation into the starting position shown in FIG. 1 in which the axis of the grinding means and of the cylindrical measuring container extend substantially vertically upwardly.

Preferably the measuring apparatus is mounted in such a way that, except for the remote measuring means (not shown), it is enclosed within a closed cylindrical drum 10 adapted to be directly mounted at the location where the sample is taken. The drive for the rotating movement may comprise an electric motor (not shown) connected to the shaft'9.

What is claimed is:

1. Grain testing apparatus of the class described, comprising: a stationary drum; grinding means disposed within said drum for rotation about a horizontal axis coaxial with said drum; sample receiving means carried by said drum and extending outwardly thereof for receiving a sample of the grain to be tested; means defining a radially extending axially compressible elongated measurement chamber communicating with said grinding means and connected for rotation therewith, said measurement chamber being positioned eccentrically with respect to the rotational axis of said grinding means for gravitational filling and discharge of the sample therefrom, an outer end portion of said measurement chamber being brought into register with said sample receiving means when said chamber is in an upwardly directed position, said drum having an outlet aperture formed therein wherewith said outer end portion 'of said measurement chamber in register when said chamber is in a downwardly directed position; temperature measurement means within said chamber; electrical resistivity measurement electrode means within said chamber; first cam-actuated slide means for selectively shutting off communication between said measurement chamber and said grinding means; second cam-actuated slide means for selectively shutting off communication between said outer end portion of said chamber and the interior thereof; resilient means biasing said chamber to elongate the same; fixedly positioned first cam means within said drum, said first cam means operating to open both of said slide means when said outer end portion of said measurement chamber is in register with said sample receiving means for delivery of said sample to said grinding means through said measurement chamber and to close said second slide means when said outer end portion moves out of register with said receiving means, said cam means closing both of said slide means when said measurement chamber has arrived at a downwardly directed position and said grinding means has gravitationally discharged the sample in ground condition into said chamber; second cam means acting on the outer end portion of said means defining said measurement chamber when both of said slide means are closed to compress said chamber whereby a predetermined pressure is applied to said sample, rotational movement of said chamber being interrupted wit-h said pressure applied to permit measurement of the temperature and electrical conductivity of said sample, said pressure being released by said second cam means after said rotational movement has been resumed; said first cam means opening both of said slide means after release of pressure by said second cam means and with said outer end portion of said chamber in register with said outlet aperture.

2. Apparatus according to claim 1, further comprising pneumatic means operative when said outer end portion of said chamber is in register with said outlet aperture for blowing said sample out of said chamber.

3. Apparatus according to claim 1, wherein said measurement chamber defining means comprises two telescopically arranged tubular members.

4. Grain testing apparatus of the class described, comprising: grinding means mounted for rotation in a predetermined direction about a horizontal axis; sample receiving means positioned above said axis for receiving a sample of the grain to be tested; means defining a radially extending compressible measurement chamber communicating with said grinding means and connected for rotation therewith, said measurement chamber being positioned eccentrically with respect to the rotational axis of said grinding means for gravitational filling and discharge of the sample therefrom, an outer end portion of said measurement chamber being brought into register with said sample receiving means when said chamber is in an upwardly directed position; outlet means wherewith said outer end portion of said measurement chamber in register when said chamber is in a downwardly directed position; temperature measurement means within said chamber; electrical resistivity measurement electrode means within said chamber; first slide means for selectively shutting oif communication between said measurement chamber and said grinding means; second slide means for selectively shutting off communication between said outer end portion of said chamber and the interior thereof; resilient means biasing said chamber against compression thereof; first actuating means operating to open both of said slide means when said outer end portion of said measurement chamber is in register with said sample receiving means for delivery of said sample to said grinding means through said measurement chamber and to close said second slide means when said outer end portion moves out of register with said receiving means, said actuating means closing both of said slide means when said measurement chamber has arrived at a downwardly directed position and said grinding means has gravitationally discharged the sample in ground condition into said chamber; second actuating means acting on said measurement chamber when both of said slide menas are closed to compress said chamber whereby a predetermined pressure is applied to said sample, measurements of the temperature and electrical conductivity of said sample being made with said sample compressed, said pressure being released by said second actuating means after further rotational movement of said measurement chamber; said 20 References Cited by the Examiner UNITED STATES PATENTS 1,890,545 12/ 1932 Limbrick 73-73 2,082,364 6/ 1937 Store. 2,343,340 3/ 1944 Stevens 737 3 2,520,394 8/1950 Franzen-Lutz et al. 324-65 FOREIGN PATENTS 885,306 12/ 1961 Great Britain.

RICHARD C. QUEISSER, Primary Examiner.

DAVID SCHONBERG, JAMES J. GILL, Examiners.

LAWRENCE R. FRANKLIN, Assistant Examiner.

Claims

1. GRAIN TESTING APPARATUS OF THE CLASS DESCRIBED, COMPRISING: A STATIONARY DRUM; GRINDING MEANS DISPOSED WITHIN SAID DRUM FOR ROTATION ABOUT A HORIZONTAL AXIS COAXIAL WITH SAID DRUM; SAMPLE RECEIVING MEANS CARRIED BY SAID DRUM AND EXTENDING OUTWARDLY THEREOF FOR RECEIVING A SAMPLE OF THE GRAIN TO BE TESTED; MEANS DEFINING A RADIALLY EXTENDING AXIALLY COMPRESSIBLE ELONGATED MEASUREMENT CHAMBER COMMUNICATING WITH SAID GRINDING MEANS AND CONNECTED FOR ROTATION THEREWITH, SAID MEASUREMENT CHAMBER BEING POSITIONED ECCENTRICALLY WITH RESPECT TO THE ROTATIONAL AXIS OF SAID GRINDING MEANS FOR GRAVITATIONAL FILLING AND DISCHARGE OF THE SAMPLE THEREFROM, AN OUTER END PORTION OF SAID MEASUREMENT CHAMBER BEING BROUGHT INTO REGISTER WITH SAID SAMPLE RECEIVING MEANS WHEN SAID CHAMBER IS IN AN UPWARDLY DIRECTED POSITION, SAID DRUM HAVING AN OUTLET APERTURE FORMED THEREIN WHEREWITH SAID OUTER END PORTION OF SAID MEASUREMENT CHAMBER IN REGISTER WHEN SAID CHAMBER IS IN A DOWNWARDLY DIRECTED POSITION; TEMPERATURE MEASUREMENT MEANS WITHIN SAID CHAMBER; ELECTRICAL RESISTIVITY MEASUREMENT ELECTRODE MEANS WITHIN SAID CHAMBER; FIRST CAM-ACTUATED SLIDE MEANS FOR SELECTIVELY SHUTTING OFF COMMUNICATION BETWEEN SAID MEASUREMENT CHAMBER AND SAID GRINDING MEANS; SECOND CAM-ACTUATED SLIDE MEANS FOR SELECTIVELY SHUTTING OFF COMMUNICATION BETWEEN SAID OUTER END PORTION OF SAID CHAMBER AND THE INTERIOR THEREOF; RESILIENT MEANS BIASING SAID CHAMBER TO ELONGATE THE SAME FIXEDLY POSITIONED FIRST CAM MEANS WITHIN SAID DRUM, SAID FIRST CAM MEANS OPERATING TO OPEN BOTH OF SAID SLIDE MEANS WHEN SAID OUTER END PORTION OF SAID MEASUREMENT CHAMBER IS IN REGISTER WITH SAID SAMPLE RECEIVING MEANS FOR DELIVERY OF SAID SAMPLE TO SAID GRINDING MEANS THROUGH SAID MEASUREMENT CHAMBER AND TO CLOSE SAID SECOND SLIDE MEANS WHEN SAID OUTER END PORTION MOVES OUT OF REGISTER WITH SAID RECEIVING MEANS, SAID CAM MEANS CLOSING BOTH OF SAID SLIDE MEANS WHEN SAID MEASUREMENT CHAMBER HAS ARRIVED AT A DOWNWARDLY DIRECTED POSITION AND SAID GRINDING MEANS HAS GRAVITATIONALLY DISCHARGED THE SAMPLE IN GROUND CONDITION INTO SAID CHAMBER; SECOND CAM MEANS ACTING ON THE OUTER END PORTION OF SAID MEANS DEFINING SAID MEASUREMENT CHAMBER WHEN BOTH OF SAID SLIDE MEANS ARE CLOSED TO COMPRESS SAID CHAMBER WHEREBY A PREDETERMINED PRESSURE IS APPLIED TO SAID SAMPLE, ROTATIONAL MOVEMENT OF SAID CHAMBER BEING INTERRUPTED WITH SAID PRESSURE APPLIED TO PERMIT MEASUREMENT OF THE TEMPERATURE AND ELECTRICAL CONDUCTIVITY OF SAID SAMPLE, SAID PRESSURE BEING RELEASED BY SAID SECOND CAM MEANS AFTER ROTATIONAL MOVEMENT HAS BEEN RESUMED; SAID FIRST CAM MEANS OPENING BOTH OF SAID SLIDE MEANS AFTER RELEASE OF PRESSURE BY SAID SECOND CAM MEANS AND WITH SAID OUTER END PORTION OF SAID CHAMBER IN REGISTER WITH SAID OUTLET APERTURE.