農業機械学会誌
Online ISSN : 1884-6025
Print ISSN : 0285-2543
ISSN-L : 0285-2543
30 巻 , 4 号
選択された号の論文の16件中1~16を表示しています
  • 増田 正三, 田中 孝, 山崎 稔
    1969 年 30 巻 4 号 p. 197-200
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    For the similitude study on the draft of bulldozing action of the vertical blade in pure dry sand, dimensional analysis was applied and dimensionless parameters which are called ∏ terms were derived as the operating and design conditions. The equation used to relate these terms was,
    D/ρgb3=(v2/hg, h/b, α)
    where, D=draft force
    b=width of blade
    h=height of blade
    v=speed of blade with respect to sand
    g=gravitational acceleration
    α=angle of blade surface to the direction of draft
    ρ=bulk density of sand
    Similar rectangular blades having various sizes were tested under the conditions of the same value of the ∏ terms except v2/hg. Though the designed speed to each blade could not be given by our experimental installation, the four categories of speed were adopted successfully. In the preliminary tests, we found that D/ρgb3 is constant for any value of v2/hg within the limits of the speed. And the following results were obtained.
    1. Dynamic similarity was found in six similar blades and it was proved that dimensional analysis is an available and feasible method to get the operating and design conditions.
    2. Draft force D is not influenced by the speed of blade within the limits of values of v2/hg tested in this study.
    3. Draft force D on a blade is proportional to the third power of characteristic length of a blade.
    4. Value of D/ρgb3 is constant for a given value of h/b and α. And it is proportional to (h/b)2.
    5. Value of D/ρgb3 is influenced by α and it is marked in case of blades of large values of h/b.
  • 田原 虎次, 藍 房和, 須藤 允
    1969 年 30 巻 4 号 p. 201-205
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    Tear down of seedling-band on the feed table has been a handicap to obtain good performance of the rice-seedling-transplanting machine. This, as was observed, was considerably influenced by friction between the seedling-band and the feed table.
    In this paper, it is tried to answer this problem by obtaining dynamic frictional coefficient of the band with various materials for the feed table.
    The results are as follows:
    1) The average dynamic frictional coefficient of the seedling-band was about 1.23. There were no clear relationships between this value and number of seedling per unit length of band.
    2) The dynamic frictional coefficient was very much influenced by moisture condition of the band and kind of soil used.
    This value was small by using band of low moisture content, and the value obtained from sandy loam band was larger than that from clayey loam band.
    3) There was no significant difference in the value of dynamic frictional coefficient between polyurethane and fushokufu (unweaved cloth) as seedling-band supporter
    4) Dynamic frictional coefficients of various materials such as steel, aluminum, teflon, vinyl chloride, and copper were measured. The smallest value was obtained from teflon, and large values from copper and aluminum.
    5) As a conclusion it is suggested that present problem can be reduced to a certain extent by replacing the materials of feed table with teflon.
  • 1969 年 30 巻 4 号 p. 205a
    発行日: 1969年
    公開日: 2010/04/30
    ジャーナル フリー
  • 1969 年 30 巻 4 号 p. 205b
    発行日: 1969年
    公開日: 2010/04/30
    ジャーナル フリー
  • 梅田 重夫, 毛利 建太郎
    1969 年 30 巻 4 号 p. 206-211
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    It was the purpose of this study to find out the pressure variations, the torque and the general properties of the power sprayer.
    The pressure in the cylinders, air chamber, discharge port, suction port and the torque on crank shaft were measured. In order to calculate the non-dimensional properties, the discharge flow and the over flow were measured.
    The pressure and torque variations per one revolution were found from the experimental results. The non-dimensional properties were expressed as a function of K (K: non-dimensional value of discharge pressure).
    The following resnlts were obtained.
    1. The pressure variations were shown in Fig 3. At the suction and discharge stroke, the fluctuations of the cylinder pressure, the air chamber pressure and the discharge pressure were small.
    2. In the power sprayer with no air chamber, the pressure fluctuations in cylinders at the discharge stroke were influenced by the fluctuation of discharge pressure (Fig 5).
    3. On the fluctuation of torque, they have 6 peaks per one revolution. As the experimental values included the friction loss, they closely correspond to those calculated by the equation 2 and 5 (Fig 7 and 8).
    4. The non-dimensional properties are shown in Fig 10, in which the difference by rotational speed of the power sprayer is found.
  • 中川 健治, 堀部 和雄, 春田 守年, 鳥潟 浩司, 津田 直和
    1969 年 30 巻 4 号 p. 212-217
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    In order to obtain an uniform distribution of water over the sprinkling area with the turning irrigation pipe, which has many orifices along the pipe and rotates alternately to the right and left, ranging from zero to 180° upward, its. desirable operating method has been studied experimentally.
    The results obtained are summerized as follows:
    1. The trajectory distance of the drops of water jetted from each orifice on the irrigation pipe is comparatively short, because the drops of water encounter with an air resistance proportional to the square of relative velocity during the drops traveling through the air.
    2. The distribution of water over the sprinkling area is changed largely with the range of a rotating angle of the irrigation pipe. For example, in case of 180° turning of the pipe (full rotation), it is found that the distribution of water is irregular, for most of the drops of water jetted from orifices at any angle ranging from 20° to 50° and from 130° to 160° fall near the outer edge of the area covered, being followed by the occurrence of the accumulation peak of the drops thereabout. This tendency is especially large at a low pressure of water. However, in case of about 80° turning of the pipe, it is sure that the distribution of water over the sprinkling area is more uniform than that in case of 180° turning, though the maximum trajectory distance decreases slightly. Therefore, 80° turning of the pipe is desirable to obtain an uniform distribution of water as compared with 180° turning. A breaze is useful for an uniform distribution of jetted water.
    3. Each orifice should be correctly bored with a drilling machine on the pipe, because uncorrectly bored orifices bring often an irregular distribution of water to the direction parallel to the pipe.
    4. If the irrigation pipe is laid at about 1 meter in height, the water distribution and trajectory distance is not influenced by the pipe height. The pipe height should be nearly equal to the plant height lest the jetted water should be intercepted by the stalks or leaves of plants.
  • 宮地 豊房, 渡海 一
    1969 年 30 巻 4 号 p. 218-224
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    Here we propose a husker roller shaping hyperboloid of one sheet of revolution as intermediate method bet ween right cylinder roller whose larger capacity of treatment is inherent, and a motor husker which has husking operation as natural function. The principle employs the slip in the direction ofthe nearest generating straight line caused by preserving an included angle between two roller axes, for husking operation.
    When the included angle between two axes is 20°, the diameters are about 76mm, and the slit breadth between two rollers is 3/10-7/10 of thickness of paddy, the slip length is 2.5-3.5mm.
    The result of husking test by static loading using these rollers is as follows. When paddy are suppliad in lying state, (it represents standing state in right cylinder roller), the husking ratio reaches 100%, and even in standing state, when the slit breadth is less than 3/10, the ratio also reaches 100%. when 6/10, it reaches about 60%.
    The reguired torque of rollers for husking is mainly influenced by the breadth of slit between the rollers. Beside, in our opinion, the greater part of this torque is consumed by inlaying rollers with paddy.
  • 宮地 豊房
    1969 年 30 巻 4 号 p. 225-230
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    Considering relative position of a couple axes, hyperboloid of one sheet of rvolution is a basic form of a pair-roller. When two hyperboloid of one sheetare contacted mutually at generating straight line, x: generating straight line in contact. y: perpendicular line to both x and z.
    z: common perpendicular of the axes of two rollers.
    a or b: minimum radius of A or B roller.
    α or β: included angle between x and the axis of A or B roller.
    p (parameter): distance from origin, on straight line in contact.
    θa or θb (parameter): revolution angle around axis of A or B roller.
    ra≡√a2+p2sin2α
    The equation of A roller is following,
    {x=ra sin α sin θa+p cos2α
    y=ra cos α sin θa-p cos α sin α
    z=ra cos θa+a
    Slipping ratio in the direction of x axis is ζhg=ra sin α cos θa+ra sin β cos θb
    On x axis, it is constant and its value is following,
    ζh=a sin α+b sin β
    On the other hand, slip in the perpendicular direction to x axis is
    ωa√p2sin2α+a2cos2α-ωb√p2sin2β+b2cos2β
    When ωa=dθa/dt, ωb=dθb/dt
    These basic formulas can be applied to the cases of right cylinder, conic and cylinder-disc rollers.
    On the generating straight line in contact, curvature of sectional curve, which is intersection of y-z parallel plain and the surface of revolution, is following
    1/ρx=|a2(1-tan2α)+x2tan2α/(a2+x2tan2α)3/2|
    Beside, geometrical and dynamical conditions for a solid to pass through between two rollers are explained.
  • 石橋 貞人, 小島 孝之
    1969 年 30 巻 4 号 p. 231-236,240
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    Advancing in knowledge of the mechanical properties of fruits and vegetables under compression has an important significance for us in all agricultural and food engineering; harvesting, handling, storing and processing etc. Information on the mechanical properties of some agricultural products tested in this experiment is as follows:
    (1) In each product, we found a considerable difference even in the same kind of products due to harvesting time, growing condition and product size.
    (2) Depending on the diameter of plunger, product variety and size, the stress-deformation curves may not have the bio-yield point on them.
    (3) As a rule, early harvested fruits are harder than the properly harvested ones, and as for fruits and vegetables except tomatoes etc., early harvested ones are softer and more delicate than the properly harvested.
    (4) The apex resistance of fruits after harvest may become stronger than the base, except a certain kind such as citrus fruits.
    (5) As for grain such as unhulled-rice, well dried grain are better than wet ones in hulling, and properly wet grain are more suitable than dry grain in crushing process.
  • 中馬 豊, 村田 敏
    1969 年 30 巻 4 号 p. 237-240
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    The thermal diffusivity coefficient, κ, of cylindrical vegetables, burdock, carrot, cucumber and radish, were calculated from rate of temperature change of the center and surface of them when they were suddenly immersed in ice-water bath. The temperature was measured and recorded with a recorder employing preamplifiers and copper-constantan thermocouples, and κ was obtained by substitution in the following equation:
    κ=1/α12 (t2-t1)lege(vo)t=t1/(vo)t=t2
    where t1 is initial time after immersion of vegetables when the semi-logalithmic curve of the center temperature versus time becomes linear, t2 is any subsequent time linear portion of curve, (vo) t=t1 is center temperature at t1, (vo)t=t2 is center temperature at t2, κ is thermal diffusivity and α1 is the smallest root of
    (va)t=t1/(vo)t=t2=Jo (aα1)
    where Va=surface trmperature at t2, a=mean radius,
    Jo (aα1)=Bessel's function of O order. From the results, the locations of the mass-average temperature of the vegetables were obtained by the following equation:
    r/a=aα1/rα1
    where r is the location of the mass-average temperature found as the root of
    2J1(aα1)/aα1=Jo(rα1)
    where J1(aα1)=Bessel's function of the first order.
  • 中馬 豊, 村田 敏, 渡辺 兼五
    1969 年 30 巻 4 号 p. 241-251
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    It was believed that the stacking pattern of cartons used in storage or transportation influenced the cooling rate of packed products.
    To find out what this influence was, a study was undertaken and following results were obtained.
    1. In the multi-stacked type of loads, the cooling rate of the products in the carton increased in accordance with cooling air flow rate. Half cooling time of 3.1 to 4.2 hours was attained with air flow of 0.23 to 0.06m3/min/kg (Fig 1).
    2. In the Vertical-vented stacked loads, remarkable cooling rate was accomplished, and the effect of opening area in a carton on the cooling rate was little under constant air flow (Fig. 2).
    3. The cooling rate of middle layer of horizontal-vented stacked loads was the lowest. On the uneveness of cooling in the horizontal vented stacked loads, the difference of location in a carton had more effect than the difference of the height of the carton.
    “Krisp cooling” as an example of this pattern is referred (Fig. 3).
    4. The cooling rate of the products in the spaced-stack loads differed much by the location of each cartons, the difference of the half cooling time being 1.5 to 3.6 hours (Fig. 4) Optimum size of channels between stacked cartons exist.
    5. The products in the spaced-stack loads was cooled more rapidly than the one in solid loads, and the products in the carton was cooled more rapidly than in the wooden box (Fig. 6).
    6. The relation between the stacking patterns and their total area of void were explained. The wooden box and the carton box were compared in the time required to remove 3/4 of field heat (2Z) (Fig. 7).
    7. Thermal conductivity, thermal resistance of the materials of carton and wooden boxes were compared.
    The temperature of wooden boxes is much influenced by surrounding air temperature (Table 1).
    8. Principle of cooling of vented-carton by chimney loading was explained.
    The cooling rate increased in accordance with the cross-sectional area of chimney space and its air velocity.
    The products at the middle layer of chimney loads was cooled later than the one at the upper and lower located cartons (Fig. 5).
    9. The chimney load and the solid load combined with vented or nonvented cartons were compared in the cooling rate (Table 2).
    The results obtained are as follows:
    (vented carton in chimney loads)>
    (vented carton in solid loads)=
    (non-vented carton in chimney loads)
    10. The method of exhausting from ceiling through the side of stacked loads had little temperature difference between upper and lower cartons of the stack (Fig. 9).
    11. The method of exhausting from ceiling through the multi-stacked shallow wooden boxes with slitted bottom had uniform cooling through all layers, and the cooling rate increased in accordance with cooling air flow rate (Fig. 10)
    12. Ventilation through suction tube inserted into the piled citrus was effective for rapid cooling (Fig. 11).
    13. Cooling rates by the stacked patterns were collected in a table (Table 3).
  • 小島 孝之, 伊東 秋人, 石橋 貞人, 嶋尾 弘
    1969 年 30 巻 4 号 p. 252-256,263
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    From October 1966 to March 1968, research and investigation on the actual condition of storge are carried out to gain the engineering data for improving citrus storage technique. We selected and researched six natural simple storages in A section and five mechanical cooling storages in B and C section in Fig. 1, Kagoshima prefecture, Japan. Investigation results were summarized as follows:
    (1) In natural simple storages such as underground type, barn type and watering under-floor type, the ratio of evapotranspiration weight loss to the total weight loss was smaller than the ratio in PRECON, mechanical cooling storage.
    (2) In the later term of storage in the natural type, green mold and stem-end-rot of citrus fruit incresed and the total weight loss also increasd exponentially.
    (3) In mechanical cooling storage (PRECON), considerable and a certain weight loss by evapotranspiration in the total weight loss continues through the storage term.
    (4) During storage, contents of acid (mainly, citric acid) (%) in citrus fruit unshu gradually decreased, especially normal temperature (natural) storage allows contents of citric acid to decrease more rapidly than the low temperature storage.
    (5) No significant tendency was recognized in the change of contents of total sugar (%) in the citrus fruits. Measurement degree by sugar refractometer to determine the sugar contents is not to be relied upon, because citrus as well as other fruits are constituted by complex ingredients which have a different index of refraction, respectively.
  • 酒井 学, 瀬川 敬, 山崎 稔
    1969 年 30 巻 4 号 p. 257-263
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    Some static and dynamic properties of various concentrates, roughage, litter and muck shown in Fig. 4, 5 and 6 was investigated.
    Based on such results as summarized in Tables 2 and 4, we proposed classification of rough materials in relation to handling (Table 5). Through our investigations, it seemed somewhat difficult and problematical to apply the measuring technique of soil mechanics to rough materials. So that, our proposal is only tentative, but will be useful to develop handling system suitable for characteristics of materials.
  • 梅田 重夫, 毛利 建太郎, 大塚 庄吾
    1969 年 30 巻 4 号 p. 264-265
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
  • 細川 明, 三枝 滋
    1969 年 30 巻 4 号 p. 266-271
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
    In an old production method of starch noodles, starch was mixed with water and extruded into fine noodles and into boiling water. The noodles were then frozen in a cold storage room, thawed in cold water, hung on bamboo sticks and dried in the sun. The new continuous method presented in this report was devised and patented by Mr. Mori, a owner of a starch noodle plant in Tokyo and was industrially materialized with writers' cooperation on engineering sides. In this new method, starch mixture with water is extruded into thin film and onto a net conveyor. Then it goes through a steam tunnel for cooking, through drying chamber to reduce moisture so that the film can be cut by a cutter into noodles and then the noodles are dried in a drying tunnel. An automatic packer may be used in connection with this method. The main features of the new processes are:
    (1) the new method requires 6-7 men to produce 1 t. of noodles a day whereas old methods required 35-40.
    (2) elimination of 80 square meters of cold storage room with a 30 PS refrigeration system and also replacement of 1, 000 square meters of drying space with a 60 square meter drying tunnel, thereby cutting the production costs by 30% but still method retaining good old qualities of starch noodles.
  • 1969 年 30 巻 4 号 p. 272-273
    発行日: 1969/03/01
    公開日: 2010/04/30
    ジャーナル フリー
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