AU605321B2

AU605321B2 - Continuous constant-rate particle feeding device with roller with grooves for feeding particles without crumbling even though these particles are readily subject to crumbling

Info

Publication number: AU605321B2
Application number: AU18683/88A
Authority: AU
Inventors: Motonari Iwako
Original assignee: FUNKEN KK
Current assignee: FUNKEN KK
Priority date: 1987-07-21
Filing date: 1988-06-30
Publication date: 1991-01-10
Anticipated expiration: 2008-06-30
Also published as: AU1868388A; CN1013855B; CN1030730A; FR2618355A1; GB2207663A; JPS6417331U; GB2207663B; GB8815386D0; DE3824700A1; DE8809299U1

Description

AUSTRALIA

PATENTS ACT' 1952 COMPLETE SPECIFICATION Form

(ORIGINAL)

FOR OFFICE USE 652 Short Title: Int. Cl: Application Number: Lodged: .!ne1'dj-ne~JUS ma'de Uflojr jrect 0ng4. n~i correct fjor 4~ 0 *0 0 o o.

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1 It it tt~t Complete Sp.--cification-Lodged: Accepted: Lapsed: Publi shed: Priority: Related Art: TO BE COMPLETED BY APPLICANT Name of Applic:.nt: Address of Applicant: KABUSHIKI KAISHA FUNKEN NO. 22-17, 7-CIOME

NISHI-GOTANDA

SHINAGAWA-KU

TOKYO

JAPAN

CLEMENT HACK CO., 601 St. Kilda Road, Melbourne, Victoria 3004, Australia.

Actual Inventor: Ad.dress for Service: Complete Specification for t %e invention entitled: CONTINUOUS CONSTANT-RATE PARTICLE FEEDING DEVICE WITH ROLLER WITH GROOVES FOR FEEDING PARTICLE11S WITHOUT CRUMBLING EVEN THOUGH THESE PART IC~ui!; ARE READILY SUB."ECT TO CRUMBLING The following statement is a full description of this invention includi.ng the best method of performing it known to me:-

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CONTINUOUS CONSTANT-RATE PARTICLE FEEDING DEVICE WITH ROLLER WITH GROOVES FOR FEEDING PARTICLES WITHOUT CRUMBLING EVEN THOUGH THESE PARTICLES ARE READILY SUBJECT TO CRUMBLING BACKGROUND OF THE INVENTION Field of the invention: S This invention relates to a continuous constanto orate particle feediiq device which is optimized to feed a particles without crumbling even though these particles o are readily subject to crumbling.

Description of the Prior Arts: o *In a system for feeding particles continuously at a predetermined desired constant-rate, if the particles o o to be fed are readily subject to crumbling, with a conventional belt or screw it is not only possible to oi cause crumbling of the particles but also it is I difficult to permit the particles to feed at a desired constant-rate. Fur2her, if the particles slip, they are liable to be crumble, or a speed error is produced, so that accurate constant-rate feeding of particles per unit rotation can not be obtained.

The present invention has proposed earlier a particle feeding device adequate for the particle material as noted above, which comprises a hopper having a bottom surface inclined by more than a rest angle of

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2 the material to be fed, a feed roller provided on the side of an outlet of the hopper and having a frictional peripheral surfar3 for friction with the material to be fed, a control gate having a semi-circular sectional profile for forming a material passage with the feed roller and a shoot disposed below the feed roller (Japanese Utility Model Publication No. Sho 53-6221), and excellent results have been recognized.

In the above proposed particle feeding device, however, despite of the fact that the material to be fed Sa,* is in the form of particles, the feed roller merely has *4*444 a roughened frictional outer periphery. Therefore, although the material can be adeq'ately fed by *4 frictional force so long as the feed roller speed is low, when the feed roller speed is increased, slip of the material occurs, resulting in failure of the proportion between the feed roller speed and the feed amount. Further, particles that are discharged from the material passage with the rotation of the feed roller will slip on the feed roller outer periphery and fall off when the feed roller reaches a certain rotational angle. Therefore, the material to be fed will fall off the shoot discontinuously.

Further, in case where the particles to be fed have a comparatively large diameter and are readily subject to crumbling, the material to be fed is liable to crumble with the phenomenon of its slip in the 3material passage.

SUMMARY OF THE INVENTION An object of the present invention is to provide a particle feeding device, which can preclude the above drawbacks in the p-i.or art and can feed particles without crumbling and continuously in proportion to the oo, feed roller speed even if these particles are readily o subject to crumbling.

0e o As has been shown in the foregoing, with thc p"I continuous constant-rate particle feeding device with a feed roller with grooves for feeding particles without crumbling even if these particles are readily subject to crumbling, it is possible to feed the particles at a constant-rate even when the material pressure in the V i hopper 3 vanishes with reduction of the material in the hopper. Also, the particles can be fed reliably and with less crumbling even if they are readily subject to crumbling. Further, the speed of the feed roller 1 and feed amount are proportional, and the particles having passed through the passage 6 will never slippedly fall off the outer periphery of the feed roller 1, so that there is no possibility that the particles are fed discontinuously.

7PL,~t P~i~Bxxrun_--- 4 According to the present invention there is provided a constant-rate feeder continuously feedinj a particulate material at a constant rate which comprises: a hopper having an upper inlet and a lower outlet and a first bottom wall inclined at an angle greater than an angle of repose of the particulate material to be fed through said lower outlet of said hopper; a rotating feed roller extending substantially along the entire length of said lower outlet of said hopper and disposed substantially below said lower outlet of said 0 am. hopper, said feed roller being substantially cylindrical and o a having on the outer peripheral surface thereof a plurality p 04 of axially extending grooves having a width and a depth °o sufficient to receive lowermost-layer particles of the °oo particulate material being fed from said hopper; and a feed gate extending substantially in parallel with said feed roller and having a substantially semi-circular constant cross-sectional profile, said feed gate cooperating with said feed roller to define a material passage through *DVV which the particulate material may be fed from said hopper, said feed gate being rotatable to adjust an opening degree S of said material passage to thereby control the feed rate of the particulate material.

The particulate material in the hopper falls into the shoot from the passage with rotation of the feed roller.

In this case, when the opening of the control gate is minimized so that the vertical dimension of the passage is Sreduced to substantially corresponding to the size of the particles, the mate.rial passes through the passage in a lateral row. If the vertical dimension of the passage is large, the particles pass through the passage in a plurality of layers one above another. At this time, the particles of the lower most layer are received in grooves formed on the outer periphery of the feed roller, and they are fed progressively with the rotation of the feed roller.

5 Therefore, there occurs no slip of the material to be fed irrespective of the speed of the feed roller, and the feed roller speed and feed amount are proportional, so that the matlrial can be fed reliably up to the last particle.

Further, even if the vertical dimension of the passage is minimized, the particles can be fed reliably 'without crumbling even if they are readily subject to crumbling.

When tha feed roller is rotated up to a certain rotational angle, the particle material falls into the shoot. At this time, the material will never slip along the f t outer periphery of the feed roller, but it is carried in the grooves to a position corresponding to a predetermined t rotational angle of the feed roller. Therefore, the U It 'tI material can fall and be fed continuously.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other objects and features of the invention will become apparent from the following description of a preferred embodiment of the invention with S reference to the accompanying drawings: in which: Fig. 1 is a schematic elevational view showing the feeder device; Fig. 2 is a side sectional view showing an essential part of the same; Fig. 3 is a side sectional view showing the essential part of the same with a control gate in a

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r: j 6 fully open state; Fig. 4 is an enlarged-scale sectional view showing the relation between groove and particle; and Fig. 5 shows graphs showing the relation between the feed amount and the feed roller speed of the continuous constant-rate particle feeding device according to the present invention and a prior-art continuous constant-rate particle feeding device, with Fig. 5(A) being for the particle feeding device according to the present invention and Fig. 5(B) being for the prior art particle feeding device.

DESCRIPTION OF THE PREFERRED EMBODIMENT Now, an embodiment of the continuous constantrate particle feeding device with a roller with grooves for feeding particles without crumbling even if the particles are readily subject to c-rurnbling will be described with reference to Figs. 1 to 5. Fig. 1 is a schematic elevational view showing the feeding device, Fig. 2 is a side sectional view showing an essential part of the same, Fig. 3 is a side sectional view showing the essential part of the same with a control gate in a fully open state, Fig. 4 is an enlarged-scale sectional view showing the relation between groove and particle, and Fig. 5 shows graphs showing the relation between the feed amount and the feed roller speed of the continuous constant-rate particle feeding device tI 7 according to the present invention and a prior art continuous constant-rate particle feeding device. In Fig. 5, graph is for the particle feeding device according to the present invention, and graph is for the prior art particle feeding device.

The particle feeding device according to the present invention comprises a hopper 3 having a bottom surface 3a inclined by more than a rest angle of the t material to be fed, a feed roller 1 provided on the side of an outlet 5 of the hopper, a control gate 3 having a semi-circular sectional profile for forming a material passage 6 with the feed roller 1 and a shoot 4 disposed below the feed roller 1. This structure is the same as the structure proposed earlier by the present invention and disclosed in Japanese Utility model Publication No.

4 Sho 53-6221. Therefore, its detailed description will be omitted.

In the particle feeding device according to the present invention having the above construction, the feed roller 1 has its outer periph(ry formed with a plurality of axial grooves 7 having a width k and a depth S such as to be able to receive lowermost-layer particles 11 of the particle material 10 fed from the passage 6.

The width k and depth S of the groove 7 may be varied depending on the particle material to be fed.

The sectional profile of the groove 7 is desirably semi- 8 circular rather than angular. The arcular surface 7a of the groove 7 permits ready tumbling and rolling of the particle 11. Thus, when the opening of the passage 6 is minimized as shown in Fig. 2, the feed roller 1 is rotated with received particles 11, and the received particles 11 are tilLt-d without beiJng carried into the passage 6 as their top touches the control gate 2.

Thus, the material 10 can be fed with less crumbling even if it consists of particles readily subject to crumbling.

Since the particles 11 of the material 10 are received in the grooves 7, there occurs no slip of the material to be fed irrespective of the speed of the feed roller 1, and the material can be reliably fed up to the last particle.

Measurement data were obtained as follows by using the continuous constant-rate particle feeding device with a feed roller with grooves according to the present invention and a prior art particle feeding device with a feed roller.

Table 1 shows data with the particle feeding device according to the present invention, and Table 2 Sshows data with the prior art particle feeding device.

Fig. 5 shows graphs of the data, with Fig. 5(A) showing data according to the present invention and Fig. showing data of the prior art.

The data shown in Tables 1 and 2 were obtained in -9case where the material was in the form of pellets readily subject to crumbling and the opening of the control gate 2 was set to a i -Y Table 1 (Present invention) Feed roller speed (rpm) 0.84 1.4 2.8 5.6 11.2 16.8 22.4 28 Time (sec.) 60 60 60 60 30 30 30 speed (n) 1 308.6 550.8 1131 2233 2215 3317 4293 5421 2 302.1 549.0 1133 2245 2233 3313 4283 5361 3 309.9 556.3 1136 2244 2202 3320 4329 5452 4 303.7 550.4 1135 2259 2223 3321 4290 5376 307.5 544.5 1134 2241 2216 3315 4312 5447 x 306.4 550.2 1133.8 2244.4 2217.8 3317.2 4301.4 5411.4 a 2.97 3.78 1.72 8.43 10.19 2.99 16.81 36.88 Accuracy 0.97 0.69 0.15 0.38 0.46 0.09 0.39 0.68 Feed Amount (kg/h) 18.4 33.0 68.0 134.7 266.1 398.1 516.2 649.4 I i 11 Table 2 (Prior Art) Feed roller speed (rpm) 8.83 17.65 26.5 35.3 Time (sec.) 30 30 30 speed (n) 1 2195 4286 5876 6530 2 2222 4196 5.44 6650 3 2222 4246 5852 6510 4 2186 4196 5842 6640 2174 4184 5904 6620 6 2198 4230 5908 6660 2199.5 4223 5871 6602 a 17.64 35.42 27.12 59.28 Accuracy 0.80 0.84 0.46 0.89 Feed Amount (kg/h) 263.94 506.76 704.52 792.24 In the Tables: n: number of times of measurement x: measured value R: average measured valcu a: standard deviation, and we have i/ (xi 3)2 n i=1 a Accuracy x 100 x As is obvious from these data and also the graphs of Fig. 5, it is possible to obtain adequate ,1

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12- Ill 12 proportional control of the feed amount determined by the speed of the feed roller 1.

Claims

1. A constant-rate feeder for continuously feeding a particulate material at a constant rate which comprises: a hopper having an upper inlet and a lower outlet and a first bottom wall inclined at an angle greater than an angle of repose of the particulate material to be fed through said lower outlet of said hopper; a rotc'ing feed roller extending substantially along the entire length of said lower outlet of said hopper sand disposed substantially below said lower outlet of said hopper, said feed roller being substantially cylindrical and having on the outer peripheral surface thereof a plurality of axially extending grooves having a width and a depth z suufficient to receive lowermost-layer particles of the particulate material being fed from said hopper; and a feed gate extending substantially in parallel with said feed roller and having a substantially semi-circular constant cross-sectional profile, said feed gate cooperating with said feed roller to define a material passage through t which the particulate material may be fed from said hopper, t said feed gate being rotatable to adjust an opening degree SIt of said material passage to thereby control the feed rate of 1' t I the partirulate material.

2. The continuous constant-rate particle feeding device according to claim 1, wherein each of said grooves has a substantially semi-circular sectional profile. DATED THIS 2ND DAY OF OCTOBER, 1990 KABUSHIKI KAISHA FUNKEN By Its Patent Attorneys: GRIFFITH HACK CO. Fellows Institute of Patent Attorneys of Australia.