All issues
Volume 34 (1972 - 197･･･
- Issue 4 Pages 292-
- Issue 3 Pages 206-
- Issue 2 Pages 112-
- Issue 1 Pages 3-
- Issue Supplement Page･･･
Volume 34, Issue 1
Displaying 1-15 of 15 articles from this issue
- |<
- <
- 1
- >
- >|
-
1972 Volume 34 Issue 1 Pages 3
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (144K) -
[in Japanese]1972 Volume 34 Issue 1 Pages 4-5
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (390K) -
Effect of Implement Mast Height on Traction of Farm TractorTomiho YOSHIDA, Taiitsu TAKEDA, Takatoshi MATSUMI, Hideo TERAO, Kazuo ...1972 Volume 34 Issue 1 Pages 6-12
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESS1) Experiment was carried out on sandy loam in soil bin of Hokkaido University to know the effect of implement mast height on traction of farm tractor.
2) The experiment was based on the fact that when the mast height i. e. geometrical location of virtual hitch point was changed and the weight transfered to the rear wheels of the tractor that was doing plowing operation under constant load increased, the travel reduction of the rear wheels decreased.
3) It was found that the specific resistance of test plows (18″×1, 14″×2, 14″×3) was decreased according to the increase of working width when the depth was the same. The result obtained above resembled the tendeney of Japanese plow.
4) As working depth of each plow increased, draft increased in second order. But the changes of horizizontal forces in top link and lower links were contrary to each other. The balance of forces that each link was loaded changed considerably depending on mast height.
5) As draft increased (from 18″×1 to 14″×3 plow) travel reduction showed significant difference by changing mast height. The reason was because, as mentioned above, at 4), the balance of forces (that each link was loaded) was changed and the weight transfered to the rear wheels increased.
6) Judging proper mast height for the test tractor based on the idea of practical max, pull which was defined by 20% travel reduction, mast height was desired to be 65cm.
7) Mast height is generally standardized to be ranged from 46 to 51cm. But from the view point of effective usage of weight transfer, it was recognized that the virtual hitch point should be placed at the center of gravity of tractor.View full abstractDownload PDF (928K) -
Relationship between the Moldboard Shape and the Path of Furrow SliceOsamu KITANI1972 Volume 34 Issue 1 Pages 13-18
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSAs a basis for the development of a high speed Japanese plow, the author studied the relationships between moldboard shape and path of furrow slices. This relationship could be used for the calculation of a high speed Japanese plow shape which has the same path of furrow slice and the same parformance as the conventional Japanese plow.
The main results are the followings.
1. By means of painting method on the plow surface, the path of furrow slices was obtained from a series of field tests. Then, the obtained path on the plow surace was measured with an optical profilograph.
2. The calculated curve of the minimum path of furrow slice did not agree with the test results. The rectified minimum path in terms of α-plane (X-Z plane) did, however, become closer to the experimental curves.
3. The rectified minimum path is expressed in formulae (8), (9) and (10) in terms of dimensions, and also in the formulae (11), (12) and (13) in terms of angles.
4. The above relationship can be used to obtain the path of furrow slice from the formula of plow shape, and vice versa. In this case, for example, the formula (18) of the path was obtained from a hyperbolic plow surface.View full abstractDownload PDF (3198K) -
On the Characteristics for the Variation of Tillage TinesMinoru KOMATU, Yasutaka KAWAGUCHI, Takashi TANAKA1972 Volume 34 Issue 1 Pages 19-27
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe shape of blade of tilling tine was examined from the standpoint of the seedbed making tillage. An L-shaped cutting edge having a 90° deflection angle was taken as the basis, with radii of curvature of 8, 18, 28, 45, 65, and 85mm and their performances were compared with those of readymade knife tine and pick tine.
1) The smaller the redius of curvature, the higher the degree of soil pulverizing and leveling and power requirement.
2) The covering efficiency of rice stubble under practical tilling condition is the highest in N45(r=b) tine and reaches 80 to 90%, and decreases for the tines with larger or smaller radius of curvature. The efficiency is the lowest in Hn tine and is around 30%.
3) The uniformity of soil pulverizing is inversely proportional to the degree of soil pulverizing expyessed by the weight mean diameter.
4) The power of the wheel axle becomes negative as the tilling torque increases exempt in Hn tine, and its rate increases as the radius of curvature decreases.
5) The fluctuation ratio of tilling torque varies a little by changing tilling depth and pitch and is about 1.40 in Nn. But the ratio decreasis by incre asing the tilling depth in Nr and Hn tines, within a range of 1.30 to 1.95. In the latter, the ratio is high at medium tilling pitch and is low at smaller or lager tillng pitch, and its region of variation is from 1.35 to 1.80.
6) The maximum tilling torque distributes in the higher torque range with higher frequency as the radius of curvature becomes shorter.View full abstractDownload PDF (1165K) -
Yasunori SHIBANO1972 Volume 34 Issue 1 Pages 28-33
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe power requirement of tillage were measured by using the small tractor attaching the drawn tillage tool in front of rotary tilling device, varying tool shape and manner of tool movement. The characteristics of the combination tillage were summarized as follows:
(1) Better results were obtained when the cutting depth of the drawn tillage tool was 70% of the cutting depth of the tine, its angle of inclination was about 15°-20°, and its share length was about 12.5-15cm.
(2) The performance of the combination tillage using simple inclined tillage tool was generally far better than that using the vertical tillage tool,
(3) For the same pulverizing effect, the total power requirement in the combination tillage was about 0.7-0.8 times as large as that in the rotary tillage.View full abstractDownload PDF (788K) -
Air Flow and Dust Movement in the Boom Duster PipeYasuo MASUDA, Noboru KAWAMURA1972 Volume 34 Issue 1 Pages 34-40
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESS(1) The air and dust flow, and the emitting volume through the boom duster pipe have been examined, in order to raise the applying ability of dust.
(2) The pressure was measured to know the state of air flow through the pipe. Dynamic pressure decreased gradually along the perforated pipe and static pressure decreased also but at the end of pipe it increased a little.
(3) An expression from Bernoulli's theorem was led to know the pressure pattern through the perforated pipe and calculated with a computer. Calculated values with the computer were compared with measured values.
(4) As a result of investigation the gush flow from orifices by means of measured values and photographs, it is thinkable that the gush flow was influenced by the static pressure through the pipe, and at the same time the orifice form was affected by the gush angle.
(5) The buoyancy by the flux of air through each orifice was calculated and was compared with the weight of unit length pipe.
(6) The approximate values of friction-loss coefficient of the perforated pipe were obtained.
(7) The relation between the electrostatic generation on plastic perforated pipe and the emitting volume of dust was examined, and the efficacy of the anti-electrification materials was tested.View full abstractDownload PDF (2720K) -
Hisashi HORIO, Noboru KAWAMURA1972 Volume 34 Issue 1 Pages 41-45
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSPreviously we devised the new threshing method and studied on this method using an experimental model. In this paper we report the results of stationary experiments of stripping device (Fig. 1) employed by our method and the comparison among various layouts of stripping device.
1) Each type of the layout of stripping device is divided into two groups; the one is with stripping reel set at right angles to traveling direction and the other, parallel, In the case of the former which is low in traveling velocity, a wider operating width must be taken to increase the rate of work. In the case of the later which is narrow in operating width, a higher traveling velocity must be taken to increase the rate of work.
2) The practical ranges of revolutional speeds of stripping reel and traveling velocities were defined by the quality of stripping. In the former type, the rotating pitch of stripping tooth must be taken for less than 45mm, lest grain should be unstrapped. In the later type, the peripheral speed of stripping tooth must be taken for 400-470cm/sec where the upper limit was given by the number of branch-breaking and the lower limit was given by the number of unstipped grains.
3) The required power of the reel shaft of the later type was less than 0.1 hp per one row under most conditions.
4) Further studies are needed to decrease the number of branch-breaking and to attach the feeding device of rice plant to stripping reel.View full abstractDownload PDF (660K) -
Takenori KOIZUMI1972 Volume 34 Issue 1 Pages 46-50
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe natural frequencies of a portable rotay cutter with an electric motor were calculated using the following simplified models.
(A) Double beam system which consists of two beams connected with each other at 5 points by springs.
(B) Double beam system connected by 3 supporting points and fixed with each other at the ends of the second beam.
Results obtained are as follows;
(1) The finite element method reqired considerably longer calculation time than the Myklestad method or Transfer Matrix method in this case, but it seemed to be convenient for analysis of complicated structure like tree limbs.
(2) Some of models in Fig. 1 or partially amended model may serve for predicting natural frequencies or for vibration analysis of such portable rotary cutters as one with an electric motor.View full abstractDownload PDF (613K) -
Akira SASAO, Syunzo ENDO1972 Volume 34 Issue 1 Pages 51-56
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe authors investigated the effect of various factors which determine the conditions of fluidization in fluidized bed, with air and grains such as soy bean, unhulled rice, brown rice, processed wheat and rape seed. Following results were obtained.
1. The minimum fluidization velocity umf may be shown by
umf={1/37.74⋅(um⋅εc)1.9⋅ρs/(1-εc)0.9}0.59
2. The limit of the height of the bed in which slugging occurs (Lc/DT)sl. may be shown by
(Lc/DT)sl=0.374 (Dp⋅ρs)-04⋅8
or (Lc/DT)sl=434.4 (ums)-0⋅96
3. The height of fluidized bed Lf may be shown by
Lf=β(u/um)1⋅12⋅Lc for u/um≤(u/um)0
Lf=25.0(u/um)3⋅56⋅Lc for u/um≥(u/um)0
where (u/um)0=(β/25.0)0⋅41
and β is a constant, and datermined to be
6≤β≤8 in this study.
4. Nomenclture
DT: diameter of pipe;
ums: theoretical terminal velocity;
um, Dp, ρs: terminal velocity, diamater and density of grain, respectivel;
Lc, εc: height and void fraction of static bed, respectively.View full abstractDownload PDF (651K) -
High-speed Economy in Terms of Machine CostOsamu KITANI1972 Volume 34 Issue 1 Pages 57-63
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe optimum speed in terms of operating cost of implements and tractor under the assuption of speeding-up or widening of operating width was computed.
After computing field capacity at a certain speed or operating width, operating cost per hour as well as cost per hectare were calculated and then compared with each other.
The following conclusions were made.
1) The economical limit in terms of cost per hour of speeding-up of Japanese plow is about 3 times as large as its conventional speed (Speed-up ratio t=3). Above this speed, widening of operating implements is more profitable. The optimum speed-up ratio in terms of operating cost per hour is a little less than 2.
2) In the case of rotary tiller, the economical limit in terms of cost per hour is t=5, and the optimum speed-up ratio is 3.5.
3) When the cost per hectare is considered, the merit of speeding-up of Japanese plows is quite small and limited in the range of t<2, and there is no clear optimum speed.
4) The speed-up of rotary tiller is always profitable from the view point of cost per hectare. The optimum speed-up ratio is about 3.
5) Economical profit of speeding-up in view of machine costs is greater for smaller machines than for larger ones.View full abstractDownload PDF (712K) -
Sea Transportation Test with Bulk ContainerYutaka CHUMA, Mutsuo IWAMOTO, Touru SHIGA1972 Volume 34 Issue 1 Pages 64-70
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSUsing a container designed for bulk loading of Citrus Unshu, the sea transportation test from Fukuoka to Tokyo was conducted to obtain the foundamental data for its practical use. In this test, in addition to the above container, 'Palletainer' widely used in the market and lattice container filled with carton boxes were used and the following results were obtained:
1. Atomospheric temperature in the bulk loaded container, which was initially lower than the air temperature in the hold, progressively rised with time after shipping.
Sea air induced into the hold during the voyage had an effect of preventing temperature rise of the fruit.
The highest in-transit air temperature was 16.5°C in the hold, 14.3°C in the bulk container and 16.6°C in the carton box.
2. Transportation of carton box filled with washed and waxed fruits is not desirable from the point of preserving quality due to the increased humidity and high temperature of air in the carton.
Relative humidity in the carton filled with untreated fruits was 75 to 80 percent.
It is desirable to circulate air and exclude moisture from the bulk container during transportation.
3. The magnitude and frequency of in-transit vibration were remarkably less than that in the case of the freight car and truck.
4. After transportation, the specific gravity and total sugar of juice were not found to be changed. The rate of flesh to total weight of the fruit treated with washing and waxing inclined to increase more than that of nontreated, and the decreasing of citric acid of nontreated fruit was. found to be less than that of treated.
5. The amount of the fruits decayed and ruptured during transportation was less than one percent in every container.
6. Moisture content of carton box filled with. treated fruits with waxing and washing reached 19.2 percent during the sea-transportation, while that of non-treated fruits was 18.7 percent.
Initial moisture content of the carton was 10 percent.View full abstractDownload PDF (5731K) -
The pre-cooler type Jacketed Room System and Effect of Precooling Methods on the Quality of Unshu Mandarin during Storage (1)Sadato ISHIBASHI, Takayuki KOJIMA, Yasuyuki SAGARA, Shunichiro TANAKA1972 Volume 34 Issue 1 Pages 71-79
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSA pre-cooler type Jacketed Room System was designed and constructed.
Studies were carried out to investigate the effect of the difference in pre-cooling and storage methods on the quality of Unshu Mandarin using the pre-cooler type Jacketed Room System, three types of pre-coolers and a conventional storage room.
The changes in the qualities such as external apperarence, weight loss, respirative rate, sugar content, acidity, and color of peel were objectively measured by instrumental methods during storage.
All of these results were discussed, and the suitable methods for the pre-cooling and storage of Unshu Mandarin were presented.
A summary of the results is given below.
1) From the point of view for the faculty of cooling and effect on the quality, vacum-cooling was not suitable for Unshu Mandarin.
2) The weight loss for 30 days on the samples stored in the jacketed room system was about half that of the standard storage room.
3) After one month storage, the decay of fruit occured in the lots of the samples pre-cooled with the hydro-cooler.
4) The respirative rate of the samples precooled with the vacum-cooler was always 5-10ppm/kg higher than that of the samples pre-cooled with hydro-and air-coolers.
5) By using a spectrophotometer, it was possible to observe the change in chlorophyll of Unshu Mandarin peel during storage. From the stand-point of controlling the peel color of Unshu Mandarin during storage, the air-cooler was the most superior to other coolers.View full abstractDownload PDF (1082K) -
A. HOSOKAWA1972 Volume 34 Issue 1 Pages 80-83
Published: June 01, 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (589K) -
1972 Volume 34 Issue 1 Pages 93
Published: 1972
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (62K)
- |<
- <
- 1
- >
- >|