JPH03146141A - Rice grain leakage detector in rice polishing machine - Google Patents

Abstract

PURPOSE:To permit the detection of leakage of rice grains in a small amt. by providing a detector via vibration-proofing member and a sensing needle in a rice bran discharge duct. CONSTITUTION:A casing 7 for a detecting device 5 is securely mounted on the wall 6 of a rice bran discharge duct 4. A detector 8 is mounted in the casing 7 via a vibration-proofing member 9 made of elastic material. A sensing needle 10 is provided extending into the duct 4. Upon contact of rice grains with the sensing needle 10, the needle vibrates differently according to the sizes of the grain. At this time, the strength and number of vibrations of the sensing needle 10 are detected by the detector 8 and converted into electric signals which are then sent to a control device 13. The detector 8 detects the shocks of vibrations in a predetermined or more magnitude of the sensing needle 10 but not a slight vibration thereof. This ensures the detection of the leakage of the rice grains in a small amt. which has been difficult by the conventional devices.

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention is a rice milling machine that is capable of immediately removing rice grains that leak out during operation due to holes or damage in the wire mesh in the milling section. This invention relates to a leak detection device used for detecting leaks.

<Prior Art> When a hole is formed in the milling wire gauze of a rice milling machine, rice grains during milling leak out from the hole, and the rice milling yield is reduced accordingly. Therefore, in order to detect this leakage, conventionally,
The following devices have been proposed. The rice grains leaking from the milling wire mesh enter the bran discharge duct and are discharged together with the bran by air transport, or during this discharge, the rice grains collide with the wall of the duct, producing noise and vibration. Jitsukō 60-284
No. 84 proposes a technology to detect leakage by sensing the collision sound with a sensor. Also, Unexamined Patent Publication No. 1-15
No. 5951 proposes a technique for detecting leakage by sensing the collision vibration of the duct at this time using a vibration switch.

<Problems to be Solved by the Invention> However, conventional leakage detection devices have the following drawbacks. In the case of collision noise as in Utility Model Publication No. 60-28484, the sensor is also activated by other sounds such as factory noise, resulting in many detection errors and poor detection accuracy.

In addition, detection sensitivity is low when the vibration is caused by collision of the duct itself, as in JP-A No. 1-155951, and it is possible to detect a large amount of leakage, but it seems that a small amount of rice grains are leaking from a small hole. It cannot be detected in such cases. However, in actual situations, what we want to know about is small leaks like this. In the case of a large amount of leakage, the yield after inspection will drop significantly, so workers are immediately concerned about the leakage (-1<), but in the case of a small amount of leakage, the yield will drop only slightly. As a result, workers may continue to work as they are for a long time without noticing, resulting in large economic losses due to the accumulation of small amounts of leakage.

In view of these points, it is an object of the present invention to provide a device that is capable of detecting a small amount of leakage and is capable of highly accurate leakage detection without causing detection errors.

<Means to Solve the Problem> The technical means of the rice grain leakage detection device of the present invention is a detection device body that converts vibration into an electric signal, a sensing needle extending from the detection device body, and a signal connection with the detection device body. The main body of the detecting device is installed via a vibration-proofing member to prevent vibrations from the rice milling machine's bran discharge duct from being transmitted to the main body of the detecting device, and the sensing needle is The rice grains are protruded into the bran discharge duct without making direct contact with the wall of the bran discharge duct. When the needle collides with the sensing needle, the main body of the detection device detects the shock vibration generated in the sensing needle at this time.

Further, the hole in the duct wall surface through which the sensing needle passes may be made slightly thicker, and the gap between the sensing needle and the hole may be closed with a thin plate made of a flexible material.

Furthermore, the detection device may be installed at a slightly rear position of the curved portion of the duct, and the sensing needle may be made to protrude inward from the curved outer wall surface in the 1-tough direction.

Function> In the rice grain leakage detection device of the present invention, the sensing needle of the detection device protrudes into the bran discharge duct. In addition, the rice bran discharged from the rice milling machine is pneumatically transported through this duct, so if rice grains are mixed in the discharged rice bran, the rice grains collide with the sensing needle. Although not all rice grains collide with the sensing needle, there is a certain probability that they will collide with the sensing needle. This collision generates shock vibrations in the sensing needle, which are detected by the detection device itself. The detection device converts this into an electrical signal and sends it to the control device.

Further, since the main body of the detection device is installed via a vibration isolating member, it is not disturbed by vibrations of the bran discharge duct, and leakage can be detected accurately. Furthermore, since the sensing needle does not come into contact with the bran discharge duct, it is possible to accurately detect the collision of rice grains. The sensing needle is affected by collisions with bran or small rice, or small vibrations are eliminated by the detection device itself, and only vibrations caused by collisions with normal rice grains are selected and detected.

Furthermore, if the gap between the hole in the bran discharge duct and the sensing needle is closed with a thin plate of flexible material, it is possible to prevent the vibration from the bran discharge duct from being transmitted to the sensing needle, and to prevent vibrations from being transmitted into the duct through the gap. It can prevent the bran etc. from leaking out.

Furthermore, if the detection device is installed at a position slightly behind the curved part of the bran discharge duct, where the duct is vertical, rice grains can be detected more efficiently. Immediately, when the rice grains pass through the curved part of the duct 1-, they gather outward from the curve due to centrifugal force, so they are slightly behind the curved part and
By positioning the sensing needle outside the vertical position, you can maximize the probability of collision with the rice grains.
It is possible to efficiently detect the leakage of rice grains, and to avoid interference with detection due to the accumulation of rice bran.

Furthermore, by using a detection device main body whose sensitivity can be freely adjusted, detection errors can be eliminated and leakage detection can be performed with high accuracy. This is because the sensing needle protruding into the duct collides with bran, small rice, and broken rice, causing a warped vibration in the sensing needle, and even when normal rice grains collide, the speed of the particles causes the sensing needle to collide. The amount of vibration received by the device changes. Therefore, if the sensitivity is fixed, it is not possible to detect with sufficient accuracy, so by making the sensitivity adjustable in this way, the minimum detection value of impact vibration can be adjusted to below, and only the vibration caused by the collision of normal rice grains can be accurately detected. You will be able to kick.

<Example> An example of the rice grain leakage detection device of the present invention will be described with reference to the drawings. 1 is the milling section of the rice milling machine. 2 is the pounding tube, and 3 is the mortuary tube, which is usually made of wire mesh or perforated plate, and the rice bran discharged from the pounding process falls here and is collected. A bran discharge duct 4 is connected to the lower end of this ridge support hopper 3. Further, a blower and a cyclone (none of which are shown) are attached to the duct 4 to transport the bran pneumatically and then collect it. This duct 4 usually has an inner diameter of about 60 to 300 mm and a transport speed of about 10 to 20 m/sec. Further, a detection device 5 is provided at a suitable location in this duct.

The detailed structure of the detection device 5 is shown in FIG. A casing 7 of the detection device 5 is fixed to the wall surface 6 of the bran discharge duct 4. The detection device main body 8 is attached to the casing 7 via a vibration isolating member 9 made of an elastic material such as rubber. 10
is a sensing needle of the detection device, which is provided in a state protruding into the duct 4. For this reason, the duct wall surface 6 has holes 11.
is formed. This hole 11 has a large diameter so that even if the sensing needle 10 swings, it will never come into contact with the edge of the hole. Reference numeral 12 denotes a thin plate made of a flexible material such as rubber, which blocks the hole 11 to prevent bran and the like from entering the casing 7. The sensing needle 10 is in a state of penetrating the thin plate 12, but since the thin plate 12 is flexible, it does not interfere with the vibration of the sensing needle 10 and does not transmit the vibration of the duct to the sensing needle 10.

When a grain of rice or the like collides with this sensing needle IO, the needle vibrates in response to the size of the object. Then, the strength and number of impact vibrations of the sensing needle 10 at this time are detected by the detection device main body 8,
After being converted into an electrical signal, it is sent to the control device 13. Note that the detection device main body 8 eliminates minute vibrations of the sensing needle IO and detects only the impact vibrations at a fixed position. usually,
The detection device consists of a sensing section and an amplifying section, and the amplifying section can adjust the sensitivity, so that the minimum value of the detected vibration intensity can be freely adjusted. The control device 13 has a built-in counter that determines that rice grains have leaked if there are shock vibrations more than a certain number of times within a certain period of time.
A signal is sent to the alarm device 14 to issue a sound or light alarm, or a signal is sent to the control section of the rice milling machine to stop the machine.

The detection device 5 may be installed anywhere along the entire length of the bran discharge duct. However, if it is installed in a horizontal location of the duct, bran etc. may accumulate at the bottom and obstruct detection, so it is preferable to install it in a vertical location. Furthermore, in terms of detection probability, it is preferable to provide the sensor at a slightly rearward position of the curved portion of the duct as shown in FIG. At a curved part of the duct, rice grains gather outward due to centrifugal force, so a sensing needle should be installed slightly behind the curved part and in a vertical position, protruding from the outer wall of the duct. However, the probability of collision with rice grains is highest. Furthermore, when selecting a curved location, a relatively gently curved location where the radius of curvature R is three times or more the diameter of the duct is more advantageous in terms of detection.

In the present invention, the type and structure of the detection device main body 8 are free.

<Effects of the Invention> The rice grain leakage detection device of the present invention is capable of detecting rice grain leakage with high accuracy by capturing only vibrations caused by collisions of rice grains without receiving interference from other sources. Therefore, it is possible to reliably detect a small amount of leakage, which has been difficult to detect with conventional devices, and to prevent a decrease in the yield of rice milling operations due to leakage.

Further, according to the second aspect of the present invention, it is possible to prevent bran from leaking out from the needle insertion hole without interfering with the vibration of the sensing needle.

Furthermore, if the detection device is provided at a position behind the curved portion where the duct is vertical, as in claim 3, leaking rice grains can be detected even more efficiently.

Furthermore, when a detection device with adjustable sensitivity is used as in claim 4, leakage of rice grains can be detected with higher accuracy by eliminating the influence of collisions with bran or small rice.

[Brief explanation of the drawing]

The drawings show an embodiment of the rice grain leakage detection device of the present invention.
The figure is a partial cross-sectional schematic diagram showing a state in which the leak detection device is installed in a rice milling machine, FIG. 2 is a sectional view in which the leak detection device is installed, and FIG. DESCRIPTION OF SYMBOLS 1... Rice polishing part of rice milling machine, 2... Milling tube, 3... Wire receiving pump, 4... Bran discharge duct, 5... Detection device,
6... Duct wall surface, 7... Casing, 8... Detection device main body, 9... Vibration isolating member, IO... Sensing needle, 1
2... Thin plate, 13... Control device, 14... Alarm device.

Claims (1)

[Claims] 1. Consists of a detection device main body that converts vibrations into electrical signals, a sensing needle extending from the detection device main body, and a control device signal-coupled with the detection device main body. It is installed through a member to prevent vibrations from the rice polishing machine's bran discharge duct from being transmitted to the detection device body, and the sensing needle does not come into direct contact with the bran discharge duct wall and can be inserted into the bran discharge duct. When rice grains are mixed in the discharged bran, the rice grains collide with the sensing needle as they flow through the bran discharge duct, and the shock vibration generated in the sensing needle at this time A rice grain leak detection device for a rice milling machine that detects the leakage of rice grains from the main body of the device. 2. A somewhat large hole is formed in the wall of the bran discharge duct, a sensing needle is made to protrude into the duct through the hole, and a gap between the sensing needle and the hole is closed with a thin plate made of a flexible material. Rice grain leakage detection device for rice milling machines. 3. A detection device is provided at a position slightly behind the curved part of the bran discharge duct where the duct becomes vertical, and the sensing needle is made to protrude inward from the curved outer wall surface of the duct. The rice grain leakage detection device of the rice milling machine according to 1. 4. The rice grain leakage detection device for a rice milling machine according to claim 1, wherein the detection device main body is adjustable in sensitivity so that the minimum value of the strength of vibration to be detected can be adjusted.