EP0218727B1

EP0218727B1 - Rice cleaning unit

Info

Publication number: EP0218727B1
Application number: EP19860902024
Authority: EP
Inventors: Soichi Yamamoto
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-03-28
Filing date: 1986-03-27
Publication date: 1989-10-18
Also published as: WO1986005716A1; AU578358B2; CH664299A5; DE3690156T1; AU5663186A; EP0218727A1; CN85103873A; JPS61222544A; CN1003981B

Abstract

A rice-cleaning unit in which the front and rear sides of the vertical rice-cleaning roller (17) are equipped with semicircular rice-cleaning roll strips (32) which are easily removable and replaceable, while the right and left sides without rice-cleaning strips form a wide inflow chamber (43). A polygonal rice-bran removing cylinder (13) is then positioned at the outside of the said rice-cleaning cylinder and rubbing devices (20, 24) are attached to the inside corners of the said rice-bran removing cylinder (13).

Description

The present invention is related to the improvement of Japan Patent Application No. 58-148615 with Publication number JP-A-6041548 applied for by the present applicant.

Invention background

Invention field

The present invention is related to the rice cleaning unit.

Description of prior state of the art

The rice cleaning unit has heretofore been commonly known as a unit in which removable, replaceable longitudinal rice-cleaning roll strips are attached and the circumference of these strips is surrounded by a polygonal rice-bran removing cylinder.
Since the rice-cleaning strips are attached to the front and rear as well as to the right and left of the rice-bran removing cylinder, it is difficult for grains of rice to flow down from the top, and thorough polishing is impossible because of a narrow-gap between the outside surface of the rice-cleaning roll strips and the inside surface of the rice-bran removing cylinder.
On the other hand, the rice-bran removing cylinder has a polygonal form-e.g. hexagonal or octagonal-in order to prevent simultaneous turning of rice grains and to ensure required polishing pressure, although efficiency is limited when resistance to rotation of rice grains depends on polygonal form only..
Therefore, the present invention as defined in claim 1, does away with such difficulties by attaching rice-cleaning roll strips to either the front and back or right and left, in order to cope with the inflow difficulty for rice grains due to the aforementioned narrow gap, or by providing a rubbing device for the inside angular section of the polygonal rice-bran removing cylinder so that the rice-cleaning roll strips come into close proximity. The dependent claims set out particular embodiments of the invention.

Brief description of the drawings

Fig. 1 is a longitudinal elevation view of the new invention, with one part broken away.
Fig. 2 is a perspective view of the rice-cleaning roll assembly.
Fig. 3 is a lateral cross-section of the rice-cleaning roll assembly and rice-bran removing cylinder.
Fig. 4 is an exploded view which illustrates the attached condition of the rubbing device and rice-bran removing cylinder.
Fig. 5 is a partial cross-section which illustrates the attached condition of the rice-cleaning roll strip and arc strip to the mating cylinder.

Description of the preferred structure

In one structure of the new invention, the number 1 indicates a frame on which the rice-cleaning assembly is mounted. The number 2 indicates an outer case for the rice-cleaning assembly, the number 3 indicates a window which is made in the side of case 2, and number 4 indicates an operating window in case 2. Inward projection 5 is provided for the top of case 2, and feed cylinder 7 is inserted through the top of opening 6, which is provided in the center of ring-like projection 5. The number 8 indicates a feed hopper which is fixed to the top of said ring-like projection 5; feed cylinder 7 and feed hopper 8 are formed separately, and feed cylinder 7 then moves up and down through case 2 quite freely.
The number 9 indicates a shaft; one end of shaft 9 is fixed to case 2 and the other end is projected inward so as not to reach feed cylinder 7. The number 10 indicates a shaft which is provided below shaft 9, then affixed to feed cylinder 7 and projected outward. Tilting rod 11 is attached between shaft 9 and shaft 10. The number 12 is a spring which pulls said feed cylinder 7 upward. The number 14 indicates a discharge port, 15 indicates a vertical rotary shaft, and 16 indicates a pulley which is attached to rotary shaft 15.
Fig. 3 illustrates a cross-section of said rice-bran cylinder 13 with rice-cleaning roller 17 inside. Rice-bran cylinder 13 consists of iron sheets in which an indeterminate number of rice-bran removing holes are made; four such perforated iron sheets are bent and combined to form the assembly of rice-bran removing cylinder 13. Four vertical pillars 19 are provided at the front and back as-well as at the right and left, then the rice-bran removing cylinders 13 and rubbing device 20 are attached with screws 44 to the inner surface of each vertical pillar 19.
The right and left ends 21 of the rubbing device 20 are projected from the vertical pillar 19, each end of the rice-bran removing cylinder 13 is fit to the outer surface, and holder 22 is then attached by fitting from the outside and securing to vertical pillar 19 by tightening with screws 23. Therefore, the rice-bran removing cylinder 13 can be replaced with removing screws 23 and detaching holder 22.
The rubbing device 24, which has the same shape as the aforementioned rubbing device 20, is fit to the inside center of the rice-bran removing cylinder 13 and secured with screws 25 from the outside.
Hollow pipe 26, which has vent holes 27, is provided at the center of the rice-cleaning roller 17 and connected to the aforementioned vertical rotary shaft 15. Gap 28 is provided around the circumference of hollow pipe 26 and mounting cylinder 29 is provided at the outside of gap 28. Mounting cylinder 29 is provided with longitudinal slits 30 at fixed intervals at the front and back as well as the right and left. Some of the longitudinal slits 30 have passages 31 to said gap 28, while others have no passage.
As illustrated in Fig. 2, the rice-cleaning strips 32 have a longitudinal square shape. In the lateral cross-section of rice-cleaning strip 32, the width of the inside which fits to mounting cylinder 29 is wider than that of the outside. Said rice-cleaning strips are fit to the front and rear sides of said mounting cylinder 29, while thin wall arc strips 33 are attached to the right and left sides in place of the rice-cleaning roll strips 32. Rice-cleaning roll strips 32 and arc strips 33 are then secured with roll holders 34. Inner edge 15 of roll holder 34 is made to fit to said slit 30, while the outer edge is enlarged by means of taper to form holding section 36. Therefore, no special machining is required for rice-cleaning roll strips 32 and arc strips 33 because both strips are fit by means of roll holder 34. Roll holder 34 is attached to mounting cylinder 29 with set screws 37. The outside wall 38 of roll holder 34 and the outside wall 39 of arc strip 33 form arc surfaces of the same radius, while the outside wall 40 of rice-cleaning roll strip 32 is remarkably extended as compared with outside walls 38 and 39.
Roll holder 34, which turns ahead of rice-cleaning roll strip 32 has no injection hole, while roll holder 34, which turns behind rice-cleaning roll piece 32, has backward injection hole 41.
As illustrated in Fig. 2, said rice-cleaning roller 17 may have two-stage construction, consisting of upper and lower sections.

Operation will be described below

Grain is supplied from feed hopper 8; it then flows thorugh the inside of feed cylinder 7 into polishing chamber 42. In this case, a lot of grain flows into enlarged inflow chamber 43 because rice-cleaning roll strips 32 are provided at the front and rear sides only and thin wall arc strips 33 are provided at right and left sides.
When rotary shaft 15 is turned from the motor through pulley 16, rice-cleaning roll 17 turns counterclockwise as shown in Fig. 3, then grain moves counterclockwise so that it is forced out by the action of rice-cleaning strips 32. Therefore, some grain is forced out through taper section 45 of rice-cleaning strip 32 and moved together with rice-cleaning roll 17, it then gets into the space between the rice-cleaning roll strip and rice-bran removing cylinder 13. When the rice-cleaning roll piece comes to the position where it is facing rubbing devices 20 and 24, grain is thoroughly polished in this position by means of resistance between rice-cleaning roll strip 32 and opposing rubbing devices 20 and 24. In this case, thorough rice polishing is possible because of the minimized gap formed between rice-cleaning roll strip 32 and opposing rubbing devices 20 and 24.
When said rice-cleaning action causes friction between rice-cleaning roll strip 32 and opposing rubbing devices 20 and 24, frictional resistance forces rice-bran removing cylinder 13 to turn counterclockwise as illustrated in Fig. 1.
When resistance increases, tilting rod 11 turns counterclockwise, centering around shaft 9, inclined tilting rod 11 then tends to a vertical position. Therefore, the volume of inflow chamber 43 is enlarged and resistance is removed, because feed cylinder 7 to which shaft 10 is attached moves downward and rice-bran removing cylinder 13 also moves downward.
Thus, polished grain is fed in behind rice-cleaning roll strip 32 and rice-bran is removed by air blowing through vent hole 27, gap 28, passage 31 and outflow hole 41, and discharged through the rice-bran removal hole 18 to the outside. Similarly, grain is polished under powerful pressure in the same manner as in commonly-known examples, when rice-cleaning roll strip 32 comes to the position where it is facing the plain section of polygonal rice-bran removing cylinder 13.
When rice-cleaning roll strip 32 or rice-bran removing cylinder 13 is damaged during operation, it can be readily replaced with a new one by removing holder 22 and screws 23. When rice-cleaning roll strip 32 is divided into two sections, as illustrated in Fig. 2, rice cleaning of different degrees can be performed simultaneously because rice-cleaning roll strip 32 can consist of two parts which differ in roughness.

Claims

1. A rice cleaning unit comprising an outer case (2), a vertical rice cleaning-roller (17) rotatably mounted within said case, a rice-bran removing cylinder (13) surrounding said cleaning-roller, characterized in that the rice-cleaning roller is provided with two diametrically opposed rice-cleaning roll strips (32) and two diametrically arc strips (33) located between said rice-cleaning roll strips (32), the radial extension of the rice-cleaning roll strips (32) exceeding that of the arc strips (33), so that wider inflow chambers (43) are formed between the rice-bran removing roller (13) and the arc strips (33).

2. The unit as claimed in claim 1, characterized in that the circumference of said rice-cleaning roll strips (32) is enclosed concentrically, and rubbing devices (20 and 24) are fixed to the inside corners of said rice-bran removing cylinder (13) so that gaps between rice-cleaning roll strips (32) and rice-bran removing cylinder (13) are made narrower at these places.

3. The unit as claimed in claim 1, characterized in that sectional geometry of said rice-cleaning roll strip (32) is made narrower from its inside to its outside such that tapered sections are formed, and arc strips (33) are then fit and fixed to said tapered sections (45).