Title of Invention

AN IMPROVED TEALEAF SIFTING APPARATUS OF VERTICAL VIBRATION TYPE

Abstract An improved tealeaf sifting apparatus of vertical vibration type comprising a screen frame (2) having a vibrating motor (1) with a spinning weight (la) instaled to the underside thereof and inclined at a desired angle, wherein on the upstream side of said screen frame (2) are provided a raw material charging chute (5) in which tealeaves as raw material are charged, a fine screen (3) and a fine tealeaf discharge port (7) in which the tealeaves having passed through said fine screen are collected, on the downstream side of said screen frame (2) are provided a rough screen (4), a rough tealeaf discharge port (8) in which the tealeaves having passed through said rough screen are collected and a shifting discharge port (9) in which the tealeaves having been not al lowed to pass through said rough screen are collected, characterized in that, said screen frame (2) is connected to a machine frame (15) through a vibration absorber means, an elastic scraper (13) is arranged on the upper surface of a screen portion (16) so as to extend over the whole width of the screen portion (16), and said scraper (13) is enabled, by a driven member (11) driven by a scraper driving portion (10), to move in the longitudinal direction of the screen portion (16) while being kept in contact with the upper surface of the screen portion (16).
Full Text BACKGROUND OF THE INVNETION
This invention relates to an improved tealeaf sifting apparatus which is used mainly for sifting tealeaves of various kinds to get ones of desired size according to their respective purposes and in which vibrations and noises produced inevitably at the time of sifting can be reduced sharply.
It has been conventionally known that a tealeaf sifting process is important in finishing tealeaves for green tea and so on. This tealeaf sifting process is the fundamental operation in finishing tealeaves and the indispensable process for removing hardened tealeaves called "yanagi" (transliterated) and powder to improve the flavor and taste of tealeaves suited for their purposes. Tealeaf sifting machines having been used heretofore are classified roughly into two types: parallel type sifting machines and vibration type sifting machines. In the former ones, a horizontal reciprocating motion is imparted to cause tealeaves to slide on a screen as wire sieve to thereby perform the sifting operation, in which case a reciprocating motion with large amplitude is performed, 'so that tealeaves are mostly caused to stand on the wire sieve. As a result, it becomes possible to sift the thin and long tealeaves in great quantity, but the thick and long tealeaves may contribute to the clogging of the wire sieve, and accordingly, in the case of performing the

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operation continuously, it has been necessary to provide a sieve clogging preventive device separately.
The latter sifting machines of the type that the wire sieve surface is moved in the vertical direction are characterized by small amplitude and "high~vibrat~ion frequency and so used mainly for sifting powdered materials in most cases. The vibration type shifting machines used for finishing tealeaves are characterized in that the amplitude is made comparatively large, the vibration frequency is made lower, and the wire sieve is equipped with dampers in several portions on the surface thereof so as to control the flow of tealeaves and cause the flow of tealeaves to be swirled with the damper portions to thereby make the tealeaves stand upright to sift out the thin and long tealeaves. This type of sifting machine, therefore, is less liable to clogging of the wire sieve and suitable for the flow process.
However, in both of the conventional parallel and vibration type sifting machines described above, the more the size of the machine is increased—for-the purpose of moving a heavy screen frame itself and handling a large quantity of tealeaves, the more the reaction thereof becomes powerful and is transmitted from a machine frame directly to the floor to cause disadvantageously the whole tea factory to vibrate, and further, because of mechanical vibration, the sifting efficiency is low for the noises therefrom, and therefore the machine is required to be increased in size as a matter of course and comes to

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occupy the greater part of the space in the factory. In consequence, it is becoming very difficult to build the factory in the urban area from the viewpoints of noise, space and so on. For this reason, fixed or coiled springs have been used customarily to prevent the vibrations and noises produced at the time of sifting tealeaves, but they still could not reduce them satisfactorily.
SUMMARY OF THE INVENTION
However, an improved tealeaf s_i__fting, apparatus according to the present invention was proposed as a result of concentrated study in view of the above- described problems of the conventional apparatus, and an object of the invention is to provide a tealeaf sifting apparatus in which vibration produced at the time of sifting tealeaves is cancelled due to absorption to prevent that vibration from being transmitted to a machine frame as much as possible to thereby prevent any vibration from being transmitted to the installation floor, so that noise produced at the time of sifting can be extremely reduced, and which has a scraper useful to the prevention of clogging.
In order to achieve the above object to solve the problems, there is provided according to the present invention an improved tealeaf sifting apparatus of vertical vibration type comprising a screen frame having a vibrating motor with a spinning weight installed to the underside thereof and inclined at a desired angle, wherein

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on the upstream side of the screen frame are provided a raw material charging chute in which tealeaves as raw material are charged, a fine screen and a fine tealeaf discharge port in which the tealeaves having passed through the fine screen are collected, on the downstream side of the screen frame are provided a rough screen, a rough- teaiLeaf discharge port in which the tealeaves having passed through the rough screen are collected and a sittings discharge port in which the tealeaves having been not allowed to pass through the rough screen are collected, the screen frame is connected to a machine frame through a vibration absorber means, an elastic scraper is arranged on the upper surface of a screen portion,so as to extend over the whole width of the screen potion, and the scraper is enabled, by a driven member driven by a scraper driving portion, to move in the longitudinal direction of the screen portion while being kept in contact with the upper surface of the screen portion.
Preferably, the vibration absorber means is a rubber spring which absorbs vibrations of the screen frame due to elastic deformation of rubber member. Further, it is preferred that the scraper driving portion is disposed above the screen portion so as to extend over the whole length of the screen portion, the driven member is so arranged as to be slidable along the scraper driving portion, the scraper is attached to a scraper holder and enabled to come into and out of contact with the screen portion by a lifting guide with which the scraper holder

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is engaged, and the scraper holder is connected to the driven member through a rubber spring.
Tealeaves are supplied_into the raw material charging chute formed on the most upstream side of the apparatus by using a suitable means and then made to move downstream while jumping about on the fine screen as wire sieve. At this time, due to the vertical vibration of the screen portion, tealeaves are thrown up and then fall on the screen portion with their positions changed variously, so that it becomes easier for the tealeaves to pass through the openings in the screen portion. The tealeaves having passed through the openings in the fine screen arranged on the upstream side are collected into the fine tealeaf discharge port which is the outlet for fine tealeaves. The tealeaves having been not allowed to pass through the openings in the fine screen are then moved onto the rough screen disposed contiguously on the downstream side and subjected to sifting on the rough screen in the same manner. The tealeaves having passed through the rough screen are collected into the rough tealeaf discharge port, and the tealeaves having been not allowed to pass through the rough screen are collected into the sittings discharge port as the siftings which are to be used for coarse green tea, for example.
Sifting of tealeaves is finished in the way described above. In the tealeaf sifting apparatus according to the invention, the screen frame and the machine frame are connected through the vibration absorber

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means, so that the vibration of the screen frame caused by a vibrating motor is not transmitted to the machine frame, thereby making it possible to reduce sharply the vibrations and noises produced at the time of sifting tealeaves. Further, all vibrations except those perpendicular to the screen portion are absorbed by the vibration absorber means, so that the screen frame is moved largely up and down without being shaken from side to side to thereby perform the sifting of tealeaves with high efficiency.
Incidentally, the spinning weight is a weight that is provided on the motor with its center of gravity off the axis of rotation of the motor for causing vibration when the motor rotates, the number of which may be one or more for each motor.
The amplitude of up-and-down motion of the screen frame is decided by the output power of the vibrating motor. Further, the speed at which the sifting of tealeaves is carried out can be optimized by setting the inclination of the screen frame at an appropriate angle. Moreover, the rotational frequency of the vibrating motor is just equal to the vibration frequency of the screen, so that a higher vibration frequency can be obtained as compared with the mechanical crank system, thereby making it possible to perform the sifting of tealeaves with high efficiency.
Furthermore, the scraper is arranged on the upper surface of the screen portion. This scraper is

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elastic and brought into elastic contact with the screen portion which is vibrated vertically, and therefore it is possible to remove the causal tealeaves of the clogging without damaging the screen portion. In addition, in the apparatus the scraper is held by the rubber spring, so that it is possible to reduce the noise produced when removing the causal tealeaves of the
BRIEF DESCRIPTION OF THE/ ACCOMPANYING DRAWINGS
Fig. 1 is a front view of a tealeaf sifting apparatus according to an embodiment of the present invention;
Fig. 2 is an illustration showing, on an
enlarged scale, a scraper portion of the sifting apparatus of Fig. 1; and
Fig_ 3 is a perspective view showing, on an enlarged scale, a spring body of an L-shaped rubber spring of the sifting apparatus of Fig. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Now, description will be given of a tealeaf sifting apparatus according to an embodiment of the present invention.
Fig. 1 shows a general construction of the
sifting apparatus of this embodiment. In Fig. 1, reference numeral 2 denotes a screen frame for guiding tealeaves downstream. One or more vibrating motors 1 are connected

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to the underside of the screen frame 2 and each vibrating motor 1 is provided with a spinning weight la so that rotation of the vibrating motor 1 causes the screen frame 2 to vibrate in the vertical direction. The amplitude of vertical vibration of the screen frame 2 can be controlled by setting arbitrarily the output power of the vibrating motor 1, and the rotational frequency of the vibrating motor is just equal to the vibration frequency of the screen, and therefore it is possible to carry out efficiently the sifting of tealeaves very quickly. The screen frame 2 is so inclined that a screen portion 16 where the sifting is performed slopes down from its upstream end (adjacent to a raw material charging chute 5) toward its downstream end (adjacent to a siftings . discharge port 9). The angle of this inclination can be set arbitrarily according to the kinds of tealeaf and so on, for example, and therefore it is possible to select the optimum moving speed for the tealeaves to be handled. Reference numeral 3 denotes a fine screen and 4 denotes a rough screen. These fine and rough screens 3 and 4 serving as sieves for sifting tealeaves are disposed fixedly on the surface of the screen frame 2 so as to be contiguous with each other. Below the fine screen 3 located on the upstream side of the apparatus is provided a fine tealeaf discharge port 7 through which high-quality tealeaves having passed through the openings in the fine screen 3 are discharged, while below the rough screen 4 located on the downstream side is provided a rough tealeaf

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discharge port 8 through which rough tealeaves having passed through the openings in the rough screen 4 are discharged. Such rough tealeaves are cut up appropriately by means of a cutting machine and then made to pass through over the screen portion 16 once more. In the embodiment, two screens, that is, the fine screen 3 and the rough screen 4 are employed, and however it is naturally possible to provide three or four screens in series in the same way, and it is also possible to provide the screens consecutively or fine and rough alternatively.
Above the most upstream end of the screen frame 2 having the above structure is provided the raw material charging chute 5 in which tealeaves as raw material are charged with a suitable means, while at the most downstream end thereof is provided the siftings discharge port 9 which is the outlet for the tealeaves having been not allowed to pass through the openings in the fine and rough screens 3 and 4 and utilized for coarse green tea. In Fig. 1, reference numeral 6 denotes a spill preventive wall by which tealeaves, when thrown up due to the vertical vibration of the screen portion 16, can be prevented from being spilled out of the apparatus.
The screen frame 2 is connected and fixed in an appropriate position on a machine frame 15 located above the screen frame 2 through the medium of L-shaped rubber springs 14 provided right and left as shown in Fig. 1. Each L-shaped rubber spring 14 comprises a spring body 31 for absorbing the vibrations from the screen frame 2 and

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two arms 32 extending outward from the spring body 31 making an angle of approx. 90° between them, for example, and is in the shape of a substantially L-letter form as a whole. The spring body 31 comprises, as shown in Fig. 3, a metallic square pipe 33 (outer shell) having a substantially square cross section, another square pipe 34 (inner shell) having a smaller cross section than the square pipe 33 and inserted in the square pipe 33 so that the diagonals of their square cross sections cross each other at an angle of 45°, and four cylindrical solid rubber rods 35 press-fitted in four spaces formed at the four corners inside the outer shell 33 (between the outer shell 33 and the inner shell 34). And, one of the two arms 32 is connected to the outer shell 33, and the other to the inner shell 34 in such a manner that the swinging movement of the arms 32 about the spring body 31 causes the relative rotational movement between the outer and inner shells 33, 34 and as a consequence the rubber rods 35 are subjected to compressive deformation so as to absorb the vibrations.
In the apparatus of this embodiment, one of the arms of L-shaped rubber spring 14 is connected to the screen frame 2, and the other arm to the machine frame 15, thereby connecting the two frames 2 and 15. Therefore, the vibration of the screen frame 2 caused by the vibrating motors 1 is prevented from being transmitted to the machine frame 15, thereby making it possible to reduce the vibrations and noises of the sifting apparatus remarkably.

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Incidentally, as for the vibration absorber
means by which the screen frame 2 and the machine frame 15 are connected, such rubber spring 14 may be substituted with a coiled spring, a leaf spring and so on, for example. However, on the basis of the experiment conducted by the present applicant, it is advisable, from the viewpoint of preventing the vibrations and noises, to employ the vibration absorber means of the type that absorbs the vibrations by making use of the elastic deformation of the rubber member, such as the rubber spring 14 described above.
An elastic scraper 13 is arranged on the upper surface of the screen portion 16 so as to extend over the whole width of the screen portion 16. The scraper 13 is moved in the longitudinal direction of the screen portion 16 while being kept in contact with the upper surface of the screen portion 16. More specifically, above the screen portion 16, a scraper driving portion 10 is so disposed as to extend over the whole length of the screen portion 16, and a driven member 11 is arranged slidably on the scraper driving portion 10. The driven member 11 is driven by the driving portion 10 so as to move linearly on the driving portion 10. The scraper 13 is attached to a scraper holding metal fitting 12 and fixed to the driven member 11 through the medium of rubber springs 19 to be described later. In the scraper driving portion 10, it is possible to adopt a mechanism in which a magnet capable of attracting the driven member—11 is arranged in a pipe and

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air is injected into the hollow portion in this pipe so that the driven member 11 is moved with the magnet, a mechanism in which the scraper driving portion 10 is made of a round bar having a screw thread cut on an outside surface thereof and the driven member 11 is screwed on it so that rotation of the driving portion 10 makes the driven member 11 move, or other mechanism, for example. Incidentally, in Fig. 2, reference numeral 18 denotes a stopper by which the driven member 11 is stopped.
In the case of the clogging with tealeaves, the scraper 13 is moved in contact with the upper surface of the screen portion 16 so as to break and remove the causal tealeaves of the clogging. The scraper 13 used for this purpose is attached to the forward end of the scraper holder 12. When the scraper 13 is out of use, the scraper holder 12 is engaged with a lifting guide 17 so as to make a gap between the screen portion 16 and the scraper 13, and therefore no problems will arise in respect of the movement of tealeaves. Namely, the scraper 13, if necessary, is moved by operating the driven member 11 and, after having been moved, returned to the starting point thereof. At this time, the scraper 13 kept in contact with the screen portion 16 is moved up by means of the lifting guide 17, thereby making the gap through which tealeaves are made to pass. Such scraper 13 is moved in contact with the screen portion 16 which is vibrated vertically, so that it is moved vertically in response to the movement of the screen portion 16, and therefore the scraper 13 is

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made of a comparatively soft material such as rubber and plastic, for example, so as to prevent the occurrence of noise. The existing scraper means, in which a plurality of scrapers are provided at regular intervals in such a manner that they are brought into contact with the lower surface of the screen portion and they can cover the amplitude range of the screen portion, is complicated in structure, and incapable of removing the causal tealeaves of the clogging with reliability because the causal tealeaves of the clogging are swept away from below, and further unsuitable for the vertical vibration type sifting apparatus.
Reference numeral 19 denotes the rubber springs which are stretched between the scraper holding metal fitting 12 and the driven member 11 and moved vertically in response to the movement of the screen portion 16. Therefore, the scraper 13 is supported by the rubber springs 19. Owing to this kind of rubber springs 19, the scraper 13 is brought into elastic contact with the upper surface of the screen portion 16, so that it becomes possible to remove the causal tealeaves of the clogging with reliability and reduce the noises therefrom.


WE CLAIM
1. An improved tealeaf sifting apparatus of vertical vibration type comprising a screen frame (2) having a vibrating motor (1) with a spinning weight (la) installed to the underside thereof and inclined at a desired angle, wherein on the upstream side of said screen frame (2) are provided a raw material charging chute (5) in which tealeaves as raw material are charged, a fine screen (3) and a fine tealeaf discharge port (7) in which the tealeaves having passed through said fine screen are collected, on the downstream side of said screen frame (2) are provided a rough screen (4), a rough tealeaf discharge port (8) in which the tealeaves having passed through said rough screen are collected and a shifting discharge port (9) in which the tealeaves having been not allowed to pass through said rough screen are collected, characterised in that, said screen frame (2) is connected to a machine frame (15) through a vibration absorber means, an elastic scraper (13) is arranged on the upper surface of a screen portion (16) so as to extend over the whole width of the screen portion (16), and said scraper (13) is enabled, by a driven member (11) driven by a scraper driving portion (10), to move in the longitudinal direction of the screen portion (16) while being kept in contact with the upper surface of the screen portion (16).

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2. An improved tealeaf sifting apparatus as claimed in claim 1,
wherein said vibration absorber means is a rubber spring (14)
which absorbs vibrations of said screen frame (2) due to elastic
deformation of rubber member.
3. An improved tealeaf sifting apparatus as claimed in either of claims
1 and 2, wherein said scraper driving portion (10) is disposed
above the screen portion (16) so as to extend over the whole length
of the screen portion (16), said driven member (11) is so arranged
as to be slidable along said scraper driving portion (10), said
scraper (13) is attached to a scraper holder (12) and enabled to
come into and out of contact with the screen portion (16) by a
lifting guide (17) with which said scraper holder (12) is engaged,
and said scraper holder (12) is connected to said driven member
(11) through a rubber spring (19).
An improved tealeaf sifting apparatus of vertical vibration type comprising a screen frame (2) having a vibrating motor (1) with a spinning weight (la) instaled to the underside thereof and inclined at a desired angle, wherein on the upstream side of said screen frame (2) are provided a raw material charging chute (5) in which tealeaves as raw material are charged, a fine screen (3) and a fine tealeaf discharge port (7) in which the tealeaves having passed through said fine screen are collected, on the downstream side of said screen frame (2) are provided a rough screen (4), a rough tealeaf discharge port (8) in which the tealeaves having passed through said rough screen are collected and a shifting discharge port (9) in which the tealeaves having been not al lowed to pass through said rough screen are collected, characterized in that, said screen frame (2) is connected to a machine frame (15) through a vibration absorber means, an elastic scraper (13) is arranged on the upper surface of a screen portion (16) so as to extend over the whole width of the screen portion (16), and said scraper (13) is enabled, by a driven member (11) driven by a scraper driving portion (10), to move in the longitudinal direction of the screen portion (16) while being kept in contact with the upper surface of the screen portion (16).

Documents:

00463-cal-1999-abstract.pdf

00463-cal-1999-claims.pdf

00463-cal-1999-correspondence.pdf

00463-cal-1999-description(complete).pdf

00463-cal-1999-drawings.pdf

00463-cal-1999-form-1.pdf

00463-cal-1999-form-18.pdf

00463-cal-1999-form-2.pdf

00463-cal-1999-form-3.pdf

00463-cal-1999-form-5.pdf

00463-cal-1999-letters patent.pdf

00463-cal-1999-p.a.pdf

00463-cal-1999-priority document others.pdf

00463-cal-1999-priority document.pdf

00463-cal-1999-reply f.e.r.pdf


Patent Number 206415
Indian Patent Application Number 463/CAL/1999
PG Journal Number 17/2007
Publication Date 27-Apr-2007
Grant Date 27-Apr-2007
Date of Filing 18-May-1999
Name of Patentee YOSHIRO HATTORI
Applicant Address 45-17, HIRAKAWAKURUMAZUKA, JOYO-SHI
Inventors:
# Inventor's Name Inventor's Address
1 MASARU HATTORI 2, MIYANOATO, SHIRAKAWA, UJI-SHI, JAPAN
2 YOSHIRO HATTORI 45-17, HIRAKAWAKURUMAZUKA, JOYO-SHI
PCT International Classification Number A 23F 3/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10-008481 1998-10-12 Japan