JP4413819B2 - Household rice milling machine - Google Patents

Description

  The present invention relates to a rice mill for home use.

  In general, in a rice mill for home use, a cylindrical rice milling screen is fitted around a milling roll driven by a motor, and brown rice put into a hopper is formed between the milling roll and the rice milling screen. Introduced inside the chamber, with the rotation of the milling roll, the whitening action is performed by adding resistance between the rice grains while sending out the brown rice. The milling roll has a feed section formed with a small pitch feed screw at the part close to the hopper discharge port (spinning chamber inlet), and the tip part on the outlet side of the milling chamber has a large pitch reverse feed screw. It is a scouring part formed by the above, and while the brown rice is fed by its feeding part, it is fed in the direction of the exit of the scouring room as a whole while applying a reverse force by the scouring part.

  Further, as a typical model of a domestic rice milling machine having the above-described configuration, there is one called a pressure type or a single-pass type (hereinafter referred to as a single-pass type). In this one-time type, in order to give a certain resistance to the above-mentioned delivery of rice grains, the exit of the milling room is closed with a resistance plate, and the rice grains are polished by causing strong friction between the internal rice grains, The whitening degree can be changed by adjusting the closing pressure of the resistance plate.

  Also, as another typical model, instead of the above resistance plate, the rice grains are circulated by connecting the exit of the milling room and the hopper with a return passage, and the milling degree is changed by adjusting the circulation time. There is what is called a circulation type.

  In any of the above-mentioned types of household rice mills, the brown rice to be polished is transferred from the hopper into the milling chamber and undergoes a whitening action by mutual friction while proceeding through the milling chamber. When high immature rice is mixed, it may be crushed and hardened by compression. As a result, the transfer resistance increases, and the rotation of the motor eventually stops, and the fine roll may be locked.

  Therefore, the home-grown rice mill of Patent Document 1 includes a control device that controls driving of the motor and rotation detection means that detects rotation stop of the motor. When the rotation detection means detects rotation stop of the motor, the control device However, the motor is reversely rotated for a certain time. As a result of the reverse rotation of the motor, the finer part on the tip side of the finer roll performs the feed action, and the small pitch feed part performs the reverse feed action, as a result of the reverse feed direction. The lump is decentralized and the lock is released.

  Further, when the milling operation is finished, the milling roll feeding action is also lost, so a large amount of brown rice or the like remains in the milling room, and sometimes the milling operation is terminated while the milling roll is in a locked state. When the next rice milling operation is started in such a state, the rotational torque of the motor is extremely low immediately after the start of rotation, so the milling roll does not rotate forward or the milling roll rotates until the rotational torque increases. Is dull.

  For this reason, there is a conventional rice milling machine that rotates forward after the motor rotates backward for a set time each time the start button is turned on (see Patent Document 2).

JP 2002-360434 A Japanese Patent Publication No.51-22

  However, in both cases of reverse rotation immediately after the start of the rice milling operation and reverse rotation of the unlocking of the motor, the brown rice that has been fed back is rubbed for a longer time than usual with the milling roll. Therefore, there is a problem that as the reverse rotation time of the motor becomes longer, more cracked polished rice is generated.

  Therefore, the problem of the present invention is that the motor lock can be smoothly released according to the state at the time of reverse rotation immediately after the start of the rice milling operation and at the time of reverse rotation of the motor unlocking, and generation of cracked polished rice It is to be able to suppress this.

  In order to achieve the above object, the present invention provides a motor for starting rice milling by turning on a start switch, a milling roll rotated by the motor, a rice milling screen fitted with a gap in the milling roll, Rotation detection means for detecting rotation stop of the motor, and when the start switch is turned ON, the motor rotates forward after reverse rotation, and when the rotation detection means detects rotation stop of the motor, the motor Is characterized in that the fixed time is longer than the reverse rotation time when the start switch is turned on.

  According to the above configuration, when the start switch is turned on, the motor rotates in the reverse direction and weakens the transfer resistance. For this reason, the motor rotates in the reverse direction smoothly regardless of the rotational torque. And the reverse rotation of the motor loosens the solid rice in the milling chamber, thereby reducing the transfer resistance. As a result, the motor smoothly starts normal rotation. The reverse rotation time when the start switch is turned on is preset in a control device such as a microcomputer provided in a domestic rice mill.

  When the rotation detecting means detects the rotation stop of the motor, the motor is reversely rotated for a predetermined time, which is longer than the reverse rotation time when the start switch is turned on. Therefore, when the start switch is turned on, the reverse rotation time of the motor is shortened and the generation of cracked polished rice is suppressed. On the other hand, at the time of unlocking, it becomes possible to set the necessary reverse rotation time, and sufficient unlocking can be achieved.

  The predetermined time is stored in advance in the control device or the like, or is determined by the control device in response to detection of the rotation stop. That is, the reverse rotation time when the start switch is turned on is determined for the purpose of reducing the residual transfer resistance of the previous rice milling operation as described above, and can be set to about 0.5 to 1 second. . On the other hand, since the predetermined time is determined for the purpose of unlocking the fine roll generated during operation, for example, the predetermined time can be set to about 2 to 4 seconds. Thus, in the above configuration, the reverse rotation time of the motor can be set according to the purpose, and as a result, the lock of the motor can be smoothly released according to the state, and the generation of cracked polished rice is prevented. Can be suppressed.

  In the above configuration, if the fixed time is fixedly set, the reverse rotation time may be insufficient when a strong lock state exceeding the assumption occurs. In such a case, the rotation detection means continuously detects the rotation stop.

  Therefore, in the above configuration, it is possible to adopt a configuration in which the certain time is extended as the number of detections of the rotation detecting means increases during one unit time. According to this configuration, even if the lock is not released by the first reverse rotation, the reverse rotation sufficient to release the lock is performed. For this reason, it is possible to set the initial value for a certain period of time short while achieving smooth rotation of the motor. As a result, it is possible to avoid an excessive reverse rotation time when the motor is locked lightly. It becomes like this. Therefore, generation | occurrence | production of the cracked polished rice is suppressed more.

  Here, one unit time is a period from a suitable trigger until a predetermined time elapses, and is a time that is a delimiter for counting the number of rotation stop detections. As the trigger, ON operation of the start switch or detection of the rotation stop is used. For example, the measurement start of one unit time and the reset after the lapse of one unit time are automatically repeated from the ON operation.

  More preferably, in the above configuration, when the number of detections reaches the upper limit number during the one unit time, a fail safe provided in advance may be activated. Here, “fail safe” refers to safety control that stops at least the rotation of the motor. For example, in addition to stopping the rotation of the motor, a display device provided in the body can also be operated.

  As described above, the configuration of the present invention is based on the relationship between the transfer resistance inside the milling chamber formed between the milling roll and the rice milling screen and the rotational torque immediately after the start of rotation of the motor. For this reason, a resistance plate is provided at the exit of the semen chamber, and therefore, it is particularly suitable for a single-through type in which the transfer resistance is higher than the circulation type.

  The rotational torque of the motor depends on the rotational speed. For this reason, transmission between the fine roll and the motor is performed via a transmission element such as a clutch, and the transmission element idles around the normal rotation to increase the rotation speed and then starts the transmission. It is also possible to employ a configuration or a configuration in which the rotational torque is amplified and transmitted.

  Here, in the above configuration, if a configuration in which the rotation shaft of the motor and the fine roll are directly connected is adopted, the transmission element can be omitted or reduced in size by adjusting the reverse rotation time by setting the set time. Can be.

  As described above, according to the rice milling machine of the present invention, when the start switch is turned ON, the motor rotates forward after reverse rotation, and when the rotation detecting means detects the rotation stop of the motor, In a rice mill for household use in which the motor rotates reversely for a fixed time, the reverse time immediately after the start of the rice polishing operation is adopted because the fixed time is longer than the reverse rotation time when the start switch is turned on. At the time of rotation and reverse rotation of unlocking the motor, the motor can be smoothly unlocked according to the state, and generation of cracked polished rice can be suppressed.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS A rice mill according to the best embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an overall configuration diagram of a main part of a domestic rice milling machine according to an embodiment. FIG. 2 is an exploded view of a main part of the domestic rice milling machine according to the embodiment. As shown in FIGS. 1 and 2, the domestic rice milling machine according to the embodiment includes a casing 20 that supports the rice milling mechanism 10 and a rice container 30 that receives the milled rice discharged from the rice milling mechanism 10.

  The rice milling mechanism 10 is a one-time system. Of course, the rice milling mechanism 10 may be of a circulation type. Specifically, the rice milling mechanism 10 includes a milling roll 12 inserted into the milling room 11, a cylindrical rice milling screen 13 fitted in the milling roll 12 with a gap, and a machine base 21 inside the casing 20. And a motor 14 supported with a constant gradient.

  The rear end portion of the fine roll 12 is directly connected to the rotating shaft 14 a of the motor 14. Further, the fine roll 12 is provided with a forward feed portion made of a spiral having a fine pitch at the base portion and a reverse feed portion made of an opposite spiral having a coarse pitch at the tip portion. Due to the reverse rotation of the motor 14, contrary to the normal case, the polishing section of the polishing roll 12 performs a feeding action, and the feeding section performs a reverse feeding action.

  The milled rice screen 13 is provided with a number of slits for discharging rice bran. An inlet 13 a of the rice milling screen 13 communicates with a lower end discharge port 15 a of a hopper 15 provided at the upper part of the casing 20. The exit of the rice milling screen 13 is inserted into the end plate 11a of the rice milling chamber 11 and opened to the outside. The end plate 11a can be freely engaged with and disengaged from the rice milling chamber 11 by a snap stopper.

  A resistance plate 17 is pressed against the outlet of the milling chamber 16 formed between the milling roll 12 and the milled screen 13 with a required pressing force. The resistance plate 17 is supported by the casing 20 via a pressure regulator 18 provided on the upper part of the rice milling screen 13.

  A discharge chute 19a attached to the end plate 11a is provided at the exit of the rice milling chamber 11. The lower end portion of the rice milling chamber 11 is opened, and a rice bran guide 11b is formed in the opened portion.

  3 (a) and 3 (b), the rice milling chamber 11 is provided with a bowl-shaped escape chute 19b for discharging the brown rice remaining in the milling chamber 16 when the operation is stopped. 13a is provided below. The casing 20 is made of resin, and the lower side of the rice milling chamber 11 in the side periphery thereof is opened forward. In this open space, the rice container 30 and the straw container 31 are juxtaposed so that they can be inserted and removed. The discharge chute 19 a and the escape chute 19 b face the rice container 30, and the straw guide 11 b faces the straw container 31. When the rice milling screen 13 is extracted from the rice milling roll 12, the brown rice remaining in the rice milling chamber 16 does not flow toward the rice kneading container 31 by the rice kneading guide 11b, but flows into the escape chute 19b due to the gradient of the rice milling screen 13, and the rice container 30 Discharged inside.

  When the start switch 22 is turned on, the motor 14 rotates in the reverse direction and then rotates forward. The milling roll 12 directly connected to the motor 14 rotates in the same manner, and the milling between the milling roll 12 and the milling screen 13 is performed from the hopper 15. The brown rice fed into the chamber 16 is polished by friction between the rice grains in the milling chamber 16. The polished rice pushes open the resistance plate 17 and jumps to the outside, and falls into the rice container 30 through the discharge chute 19a (see FIGS. 1 and 2). The straw generated at that time is discharged through a large number of slits provided in the rice milling screen 13 and falls into the straw container 31 from the straw guide 11b. When it is detected by a hopper discharge port sensor (not shown) that all the brown rice in the hopper 15 has been discharged, the motor 14 is stopped to complete the rice polishing.

  Next, the drive / control device 40 of the motor 14 mounted on this household rice mill will be described. The drive / control device 40 constitutes a rotation detection means that detects the rotation stop of the motor 14 and a control device that controls the drive of the motor 14. Specifically, as shown in FIG. 4, in the drive / control device 40, the power switch 41 is provided with the start switch 22, and the start switch 22 is connected to the load current detection circuit 43 via an interface 42 such as a relay. Is provided. A current is supplied to the motor 14 through the load current detection circuit 43. The load current value detected by the load current detection circuit 43 is input to the microcomputer 45 through an appropriate interface 44. A command from the microcomputer 45 to the motor 14 is issued through the interface 42.

  The microcomputer 45 determines that the rotation of the motor 14 is stopped when the load current detected by the load current detection circuit 43 is equal to or greater than a specified value, and controls driving of the motor 14 based on the detection result. In addition, the microcomputer 45 counts the number of rotation stop detections, stores a detection counter function, a timer function that counts one unit time according to the count number of the detection counter function, and when the start switch is turned on. Set time (0.5 seconds in this embodiment) to reversely rotate the motor 14, and a fixed time (in this embodiment, the initial value is the reverse rotation of the motor 14 according to the count number when rotation stoppage is detected) 2 seconds), the function of storing the upper limit number of counts (3 times in this embodiment) during one unit time (10 seconds in this embodiment), and the stopping of the motor 14 when the upper limit number is reached. A fail-safe function for operating the display device 23 (see FIG. 2) and a fixed time calculation function for extending the fixed time as the count number increases during one unit time. That.

  In this embodiment, the fixed time calculation function calculates the fixed time = initial value + (count number−1) × 1 [second]. That is, in this embodiment, the fixed time is calculated as 2 seconds for the first time and 3 seconds for the second time in one unit time.

  FIG. 5 is a flowchart of motor drive control by the microcomputer 45. That is, when the start switch 22 is turned on (S1), the motor 14 is rotated reversely for 0.5 seconds (S2), and then the motor 14 is rotated forward (S3).

  Next, monitoring of the load current detected by the load current detection circuit 43 is started (S4), and if the load current is below a certain specified value, the rice polishing is continued until the rice in the hopper 15 runs out (S5). . When the sensor detects that the whole amount of polished rice for one batch has been discharged from the hopper 15, the motor 14 is stopped to complete the polished rice (S6).

  In (S4), when the load current is equal to or greater than a predetermined value, reverse rotation processing of the motor 14 is started, and when this reverse rotation processing is completed, the motor 14 is rotated forward (S7).

  FIG. 6 is a flowchart showing details of the reverse rotation process of the motor 14 in (S7). When the microcomputer 45 detects that the load current is equal to or greater than the specified value, the microcomputer 45 checks whether or not the value of the detection counter is “0” (S10). Measurement is started (S11). The timer function counts the remaining time from 10 seconds to 0 seconds.

  In (S10), when the value of the detection counter is other than “0”, it is confirmed whether the measurement time by the timer function is “0” (whether it is within one unit time) (S12). When it is “0”, the count number of the detection counter is cleared (S13).

  If the measurement time is other than “0” in (S12), the detection counter increments the count by “1” and stores the result (S14). This (S14) is also executed after (S11) and (S13).

  After (S14), it is checked whether or not the value of the count number is “3” or more (S15). If it is “3” or more, the fail-safe function is activated (S16).

  In (S15), when the value of the count number is “3” or less, a fixed time for reversely rotating the motor 14 is calculated by a fixed time calculation function (S17), and the motor 14 is moved only for the calculated fixed time. Reverse rotation is performed (S18). For this reason, even if the lump of the brown rice has been crushed around the milling roll 12, it is dispersed and removed by the reverse rotation of the milling roll 12. As a result, the locked state is automatically canceled when returning to normal motor drive.

Whole part block diagram of domestic rice milling machine concerning embodiment 1 is an exploded perspective view of a main part of the household rice milling machine in FIG. (A) Perspective view of the escape chute of the rice milling mechanism of FIG. 1, (b) Cross-sectional view of line III-III of the escape chute of the rice milling mechanism of FIG. 1 is a block diagram showing a drive / control circuit of a motor mounted on the domestic rice milling machine of FIG. Flowchart of motor drive control performed by the microcomputer of FIG. Flowchart of motor reverse rotation process of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rice milling mechanism 11 Rice milling chamber 11a End plate 11b Rice bran guide 12 Milling roll 13 Rice milling screen 14 Motor 14a Rotating shaft 15 Hopper 15a Lower end discharge port 16 Milling chamber 17 Resistance plate 18 Pressure regulator 19a Discharge chute 19b Relief chute 20 Casing 21 Machine base 22 Start switch 23 Display device 30 Rice container 31 Rice cake container 40 Drive / control device 41 Power supply circuit 42, 44 Interface 43 Load current detection circuit 45 Microcomputer

Claims (2)

A motor for starting rice milling by turning on the start switch, a milling roll rotated by the motor, a milling screen fitted to the milling roll with a gap, and a rotation detecting means for detecting rotation stop of the motor. In a rice milling machine for home use in which when the start switch is turned ON, the motor rotates in the forward direction after rotating in the reverse direction, and when the rotation detecting means detects the rotation stop of the motor, the motor rotates in the reverse direction for a predetermined time. the predetermined time, the start switch is rather long than the reverse rotation time when oN operation in accordance with increases during detection count is a unit time of the rotation detecting means, said predetermined time is extended A unique rice milling machine for home use. Wherein the number of detections reaches the upper limit number of times during the time unit, household rice mill according to claim 1, the fail-safe for rotating stop of the motor is activated.

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