JP4467461B2 - Rice milling machine - Google Patents

Description

  The present invention relates to a rice mill, and more particularly to a small rice mill for use in rice mill stores, homes and the like.

  Small rice mills are usually used in small places such as rice mills and homes, and in such places, for example, at a point 1 m away from the small rice mills, the sound pressure level is about 71 to 73 dB (decibel). It is known that noise is generated, and noise until brown rice is put into a rice mill and polished is an obstacle to daily life for users. This noise problem has become an urgent issue for small rice mill manufacturers. In addition, although this invention is demonstrated in detail below about a small rice mill, it is not limited to a small rice mill, It can implement also in a general rice mill.

  By the way, rice milling sound generated from a small rice mill during milling, that is, the main sources of noise are the sound generated from the milling part, the sound generated from the power source such as a motor, the power of the belt, pulley, gears, etc. There are sound generated from the transmission unit, sound generated by vibration of the chassis that covers the frame, the small rice milling machine, and the sound of rice flowing.

  Therefore, conventionally, the following method has been adopted as a method for reducing the noise of a small rice mill, either alone or in combination. That is, (1) A method of reducing the gap between the casings of the small rice milling machine as much as possible to prevent the sound generated in the casing from leaking outside, (2) Soundproofing material (sound insulating material, sound absorbing material on the inner surface of the casing) ) To prevent the sound from leaking to the outside, (3) Vibration transmission is suppressed by fixing the motor, power transmission unit, and precision unit, which are the sources of vibration, with a vibration isolator such as rubber, A method of reducing sound generated by vibration (mainly sound generated from the casing itself by vibration) (see Patent Document 1), (4) The casing is made of a damping material, and the sound generated from the casing itself is reduced. (5) A method of reducing the noise of a small rice mill such as a method of suppressing vibration by attaching a damping material to the casing and reducing sound generated from the casing itself is adopted.

  FIG. 11 is a vertical cross-sectional view of a conventional small rice mill 20 that employs a method for reducing sound generated by vibration, similar to that described in Patent Document 1. The configuration of the small rice mill 20 and the cause of the above-mentioned noise of about 72 dB will be described with reference to FIG. As shown in the figure, the small rice mill 20 has a tank lid 2 that covers the tank 1 at the top, and 3 indicates a milling unit that communicates with the tank 1 and mills the brown rice, and includes a cerealing screw 4, a milling roll 5, And a descreening screen 6. On the exit side of the finer section 3, there is provided a resistance plate 7 that is spring-biased so as to close the outlet, and the spring pressure of this resistance plate 7 is adjusted by turning the whiteness degree dial 8. The spring pressure of the blocking resistance plate 7 is adjusted, and the whiteness of the polished rice can be set stepwise.

  The cylindrical main shaft 11 includes a cerealing screw 4 provided with a screw-shaped convex portion having a flat head on the main shaft 11 and a flat head at a position opposite to the main shaft 11. About one third on the axis is substantially rectangular, and the rest is composed of a fine roll 5 having a gently curved convex part, and is driven to rotate by a motor 12 via a belt 15 and a pulley. The brown rice supplied from the tank 1 is refined and whitened while passing through the milling unit 3. The rice bran peeled from the brown rice is discharged from the dehulling screen 6 surrounding the cerealing screw 4 and the milling roll 5 and collected in the kneading box 13. On the other hand, the white rice is discharged from the exit side of the milling section 3 against the resistance plate 7 adjusted so as to close the outlet with spring pressure, and is discharged to the white rice outlet 14. The finer 3 and the motor 12 are accommodated in a casing composed of a main body frame 40 which is a vertical frame, a tank lid 2 and a bottom plate 30 on the bottom, and the motor 12 has a portal base 12a which will be described later. It is attached to the bottom plate 30 via.

  FIG. 12 is a view of the small rice milling machine 20 as viewed from the back, and FIG. 13 is a view of the gate-type table 12a that supports the motor 12 when the small rice milling machine 20 is viewed from above. As shown in FIGS. 12 and 13, the periphery of the motor 12 is supported by a flange 12b formed at a substantially right angle from a single gate-shaped table 12a. The elastic members 12c are respectively provided at the four corners, and the vibration sound of the motor 12 mounted on the bottom plate of the small rice mill 20 is reduced through the elastic members 12c. A plurality of vent holes 31 are provided in the bottom plate 30.

  In this way, the conventional small rice mill 20 rotates the milling roll of the milling unit 3 for milling brown rice by the motor 12 incorporated in the small rice mill 20, so that the motor 12 generates heat. The part 3 and the motor 12 are accommodated in the above-described casing and are difficult to dissipate heat as they are. On the other hand, since there is an upper limit on the usable temperature of the motor 12, a vent (hole) 31 is conventionally provided in the bottom plate 30 of the housing or the main body frame 40 which is a vertical frame to cool the inside of the housing by taking in outside air. is doing. However, the rice milling machine provided with the vent 31 on the back of the bottom plate 30 and the main body frame 40 can cool the inside of the casing, but the sound generated inside the casing leaks directly from the vent 31. The small rice milling machine 20 provided with the vent 31 has a problem that noise such as milled rice leaking out increases. Specifically, as already described, noise of about 71 to 73 dB (decibel) is generated at a sound pressure level at a point 1 m away from the small rice mill 20.

Therefore, in order to reduce this noise of the small rice milling machine 20, there is a method of providing air permeability while reducing the leakage of sound by providing a sponge in the vent 31. However, a structure for taking in outside air by natural convection from the hole In the small rice milling machine 20, even if a sponge is provided, the air permeability is greatly hindered, so that it is difficult to achieve both air permeability and sound insulation, which further increases the cost. In addition, the prior art document which solves the said problem which the small rice milling machine 20 has is not found at present.
JP 2000-61327 A

  The present invention is a small rice mill in which a scouring roll of a scouring section and a motor that drives the scouring roll are surrounded by a casing, and the casing is provided with a vent for cooling the motor. An object of the present invention is to provide a small rice mill that can reduce noise while maintaining the above.

To achieve the above object, a first aspect of the invention, a pearling roll 搗 fine portion, a motor and enclosed in a housing to drive it, rice mill having a vent for cooling the motor casing A wall portion having a predetermined height extending substantially vertically along the periphery of the surface of the sound-insulating plate sized to cover the vent hole, except for two opening portions on the entire circumference thereof, attaching said wall portion upper end to said vent periphery, said cover in sound insulation board said vent periphery from the outside of the housing, extending substantially vertically at a predetermined distance into the opening portion in front of one place, the sound insulation A sound insulation wall larger than the width and height of the plate is provided.
According to a second aspect of the present invention, in the rice mill according to the first aspect of the present invention, a soundproof material is attached to the surfaces of the sound insulating plate and the sound insulating wall.

The sound insulation plate has a wall portion having a predetermined height extending substantially perpendicularly to the entire circumference except for the two opening portions, and the width and height of the sound insulation plate extending substantially vertically in front of one opening portion. because provided outside the casing of the sound insulation wall can reduce noise rice mill since no outgoing noise before the rice mill (or top) and the left-right direction. On the other hand, since the sound insulation plate is separated from the ventilation opening by two opening portions and the passage of the refrigerant such as outside air is easy, the cooling effect in the housing can be maintained.

  An embodiment of the small rice mill of the present invention will be described. FIG. 1 is a perspective view of a sound insulating plate provided in the small rice mill of the first embodiment. The sound insulating plate 16 has a substantially rectangular shape as a whole, is provided with a wall 16a having a predetermined height extending vertically along three sides of the four sides, for example, a height of about 10 to 20 mm, and on the other side. The wall portion 16a is not provided. The material of the sound insulating plate 16 may be an iron plate made of the same material as that of the housing, or may be a material such as a resin that can obtain a sound insulating effect in the same manner as the iron plate.

  A small rice mill 20 according to the first embodiment will be described with reference to FIG. Here, since the overall structure and the like of the small rice mill 20 are the same as those of the conventional one shown in FIG. 11 already described, the same portions are denoted by the same reference numerals and description thereof is omitted. The sound insulating plate 16 is provided at a position outside the housing, which is separated from the vent 31 of the bottom plate 30 of the housing shown in FIG. When the sound insulating plate 16 is attached to the bottom plate 30 of the small rice milling machine 20, it is attached so that the portion without the wall portion 16a (hereinafter referred to as “opening portion”) faces backward.

  The sound insulation plate 16 viewed from the bottom of the small rice mill 20 will be described with reference to FIG. The sound insulation plate 16 provided on the bottom plate 30 is sized to cover the entire vent 31 and the opening of the sound insulation plate 16 is attached so as to face the rear direction of the bottom plate 30, so that the noise is directly small. There is no leakage in the front direction of the rice milling machine 20.

  By providing the sound insulating plate 16 with the three side walls 16a in the same position and direction as described above, noise leaking directly from the vent 31 is reflected and attenuated by the sound insulating plate 16, but the sound insulating plate 16 is placed around the vent. Since the noise is reflected by the wall portions 16a attached to the three sides, the noise is further reflected and decays compared to, for example, the case where the noise is reflected by the wall portions 16a on the front and rear sides. When noise is reflected by the wall portions 16a on the front and rear sides, when the sound wave of the noise collides with the sound insulation plate 16, the attenuated sound goes out in the left and right directions of the small rice mill 20, but the sound insulation plate 16 Is supported by the three side wall portions 16a, noise is not emitted in the front and left and right directions, so that the noise of the rice milling machine can be reduced. On the other hand, since the sound insulating plate 16 is separated from the vent 31 in the rearward direction and the passage of refrigerant such as outside air is not hindered, the cooling effect in the housing can be maintained.

  In addition, although what attached to the outer side of a housing | casing was demonstrated as an attachment position of the sound insulating board 16, 2nd Embodiment which attaches the sound insulating board 16 to an inner side of a housing | casing is described below. FIG. 4 is a view showing the sound insulating plate 16 provided inside the housing below the back surface of the main body frame 40 of the small rice milling machine 20. The sound insulating plate 16 is sized to cover the entire vent 31 provided below the back surface of the main body frame 40, and the three side walls 16a of the sound insulating plate 16 are supported inside the housing, and the opening portion thereof. Is attached in the direction below the small rice milling machine 20.

  In this case, in the first embodiment, the noise that has passed through the vent 31 is reflected and attenuated by the sound insulation plate 16, but in the second embodiment, the noise is reflected by the sound insulation plate 16 and attenuated, and the wall of the noise is a wall. Noise diffusely reflected in the direction of the lower part without the portion 16a leaks from the entire vent 31 toward the back of the small rice mill 20. For example, when compared to a structure in which two side walls 16a in the left and right direction are attached to the inside of the casing and the noise is reflected, the noise is reflected and attenuated by the sound insulating plate 16, and the noise is not up and down without the wall 16a. The noise diffusely reflected in the direction of the portion leaks from the entire vent 31 toward the back of the small rice mill 20.

  As described above, the second embodiment having no wall portion 16a at one place theoretically halves the diffusely reflected noise that leaks toward the back of the small rice milling machine 20 as compared with the case without the wall portion 16a at two places. effective. From the above description, it is effective to halve the irregularly reflected noise if a place without the wall portion 16a is provided in one place in any of the upper, lower, left and right positions. On the other hand, since the sound insulating plate 16 is separated from the vent 31 at the opening portion, and the passage of the refrigerant such as outside air is not hindered, the cooling effect in the housing can be maintained.

  FIG. 5 is a rear view of the small rice mill 20. The sound insulating plate 16 is sized to cover the entire vent 31 provided below the back surface of the main body frame 40 of the small rice milling machine 20, and the opening portion of the sound insulating plate 16 faces the direction below the small rice milling machine 20. It is attached inside the housing.

  By the way, when the ventilation hole 31 was provided in the back surface of the main body frame 40, the 2nd embodiment which provided the sound insulation board 16 inside the housing | casing of the small rice milling machine 20 was demonstrated, but the sound insulation board 16 is provided in the housing outer side. It may be provided. In that case, the opening portion is preferably provided on the outside of the housing in the downward direction. The reason is that the noise leaked in the lower direction is reflected by the floor or the like on which the small rice milling machine 20 is placed, and the noise is attenuated. It is less attenuated than that. Further, in the case where the vent hole 31 is provided in the bottom plate 30, the embodiment in which the sound insulating plate 16 is provided on the outer side of the small rice milling machine 20 has been described with reference to FIGS. 2 and 3, but the sound insulating plate 16 is provided on the inner side of the case. It may be provided. In that case, as described in the second embodiment, the effect of halving the irregularly reflected noise can be obtained by providing a place without the wall portion 16a at one place in any one of the front, rear, left and right.

  A second other embodiment in which the sound insulating plate 16 is attached to the upper inside of the back surface of the main body frame 40 according to FIG. 6 will be described below. FIG. 6 is a view showing the sound insulating plate 16 provided above the back surface of the main body frame 40 of the inner machine of the small rice milling machine 20. As in FIG. 3, the sound insulating plate 16 is sized to cover the entire vent 31 provided above the back of the main body frame 40 of the small rice milling machine 20, and the sound insulating plate 16 is supported by three side wall portions 16a. And the opening part is attached toward the downward direction of the small rice milling machine 20. Even when the sound insulation plate 16 is attached to the upper inner side of the back surface of the main body frame 40 shown in FIG. As long as there is no place in any one of the top, bottom, left and right, there is an effect of halving the diffusely reflected noise.

  7 is a longitudinal sectional view taken along line B shown in FIG. The shape, installation position and direction of the sound insulation plate 16 shown in FIGS. 2 and 3 are the same. On the surface of the sound insulation plate 16 facing the vent hole 31, a soundproof material 16b such as urethane foam is attached. By attaching the soundproofing material 16b to the sound insulating plate 16, the noise is further attenuated by the sound absorbing effect of the sound insulating material 16b in addition to the reflection effect of the sound insulating plate 16. In the case of the embodiment shown in FIGS. 4 to 6, a soundproof material 16b such as urethane foam is attached to the left side surface of the sound insulating plate 16 in FIG.

  A small rice mill 20 according to the third embodiment will be described with reference to FIG. Here, since the overall structure and the like of the small rice mill 20 are the same as those of the conventional one shown in FIG. 11 already described, the same portions are denoted by the same reference numerals and description thereof is omitted. In the configuration of the sound insulating plate 16 already described, the opening portion is not located at one place but at two places in the front-rear direction at the position outside the case that is separated from the vent 31 of the bottom plate 30 of the case shown in FIG. The sound insulating wall 16-1 is provided so as to be separated from the front of the opening so as not to prevent outside air from passing through, and the sound insulating wall having a shape larger than the width and height of the sound insulating plate 16-1 on the opening side. 16-2 is erected on the bottom plate 30, and its mounting position is a position parallel to the front opening portion of the sound insulating plate 16. The structure composed of the sound insulation plate 16-1 and the sound insulation wall 16-2 is hereinafter referred to as a “separation sound insulation plate 17”.

  The separation sound insulating plate 17 viewed from the bottom of the small rice mill 20 will be described with reference to FIG. The sound insulation plate 16-1 provided on the bottom plate 30 is sized to cover the entire vent 31, and the opening portion of the sound insulation plate 16-1 is attached so as to face the front-rear direction of the bottom plate 30. Since the sound insulation wall 16-2 is provided at the mounting position, the noise leaked from the front of the sound insulation plate 16-1 is reflected by the sound insulation wall 16-2 and directly leaks in the forward direction of the small rice mill 20. Absent. Moreover, since the front-back direction of the sound insulation board 16-1 is vacant, since external air can pass from the front-back direction of the sound insulation board 16-1, the cooling effect in a housing | casing can be maintained.

  The material of the separation sound insulating plate 17 may be an iron plate made of the same material as that of the housing, or may be a material such as a resin that can obtain the sound insulating effect in the same manner as the iron plate. Furthermore, a soundproof material 16b such as urethane foam may be attached to the surface of the sound insulation board 17. A soundproof material 16b such as urethane foam is attached to the inside of the sound insulating plate 16-1 and the right side of the sound insulating wall 16-2 shown in FIGS. By attaching the soundproof material 16b to the sound insulation wall 16-2, noise is further attenuated by the sound absorption effect of the sound insulation material 16b in addition to the reflection effect of the sound insulation wall 16-2.

  The separated sound insulation plate 17 of the fourth embodiment provided outside the back of the main body frame 40 of the small rice mill 20 will be described with reference to FIG. The air vent 31 on the back surface of the main body frame 40 is provided below, and the separation sound insulating plate 17 is provided at an outer position separated from the back surface of the main body frame 40 by about 10 to 20 mm. When the sound insulating plate 16-1 is attached to the main body frame 40 of the small rice milling machine 20, the sound insulating plate 16-1 is attached so that the opening portion faces the vertical direction. A sound insulation wall 16-2 having the same structure as the sound insulation wall 16-2 described in the description of FIGS. 8 and 9 is provided in the upper direction so as to be separated from the outside so as not to prevent outside air from passing therethrough. The material of the sound insulation board 17 and the attachment of the sound insulation material 16b to the sound insulation board 17 are the same as those described with reference to FIGS.

  Further, even when the vent 31 on the back surface of the main body frame 40 is installed in the upward direction, it is possible to use the separated sound insulating plate 17 of the fourth embodiment. The attachment of the soundproofing material 16b is the same as that described with reference to FIGS. By providing the spaced sound insulation plate 17 described according to FIG. 10 outside the back of the main body frame 40, noise leaked from above the sound insulation plate 16-1 is reflected by the sound insulation wall 16-2. The noise leaking upward of 20 is reduced. In addition, since the sound insulation plate 16-1 is vacant in the vertical direction, the heat generated from the motor is dissipated from above, and cold outside air flows from below and convection of the outside air easily occurs. Can be maintained.

It is a perspective view of the sound insulation board of 1st Embodiment. It is a figure of the small rice milling machine of 1st Embodiment. It is a diagram of the sound insulation plate as seen from the bottom of the small rice mill. Is a diagram of a sound insulating plate provided in the housing side of the lower body Wakuse surface of the second embodiment. FIG. 5 is a rear view of FIG. 4. It is a diagram of a sound insulating plate provided in the housing side of the upper body Wakuse surface of the second embodiment. It is a longitudinal cross-sectional view in the B line shown in FIG. It is a figure of the small rice milling machine of 3rd Embodiment. Is a diagram of spaced sound insulation plate as seen from the bottom of the small rice mill. It is a figure of the small rice milling machine of 4th Embodiment. It is a longitudinal cross-sectional view of a conventional small rice mill. It is the figure seen from the back of a small rice mill. It is the figure of the gate type stand seen from the small rice milling machine .

Explanation of symbols

DESCRIPTION OF SYMBOLS 12 ... Motor, 16 ... Sound insulation board, 16a ... Wall part, 16b ... Soundproof material, 20 ... Small rice mill, 30 ... Bottom plate, 31 ... Vent.

Claims (2)

In a rice milling machine comprising a milling roll of a milling unit and a motor for driving the milling machine surrounded by a casing, and a ventilation hole for cooling the motor in the casing.
A wall portion having a predetermined height is provided along the peripheral edge of the surface of the sound insulating plate sized to cover the vent hole, except for two openings on the entire circumference, and extending substantially vertically. An upper end of the part is attached to the periphery of the vent, and the sound insulating plate covers the periphery of the vent from the outside of the housing, and extends substantially vertically at a predetermined distance in front of one opening portion. A rice mill characterized by providing a sound insulation wall larger than the width and height . In the rice mill of Claim 1,
A rice milling machine , wherein a soundproofing material is attached to the surface of the sound insulating plate and the sound insulating wall .

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