農業機械学会誌
Online ISSN : 1884-6025
Print ISSN : 0285-2543
ISSN-L : 0285-2543
30 巻 , 1 号
選択された号の論文の11件中1~11を表示しています
  • 1968 年 30 巻 1 号 p. 1
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
  • 竹田 策三
    1968 年 30 巻 1 号 p. 2-4,12
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
    The test of the declination of oil was carried out and the following results were obtained, in the transportation of timbers with two fork lift trucks, of which one had diesel engine and the other a LPG engine.
    1. In both engines, the engine oils needed not be exchanged even after operating the engines for 300hrs.
    2. The declinaton of the engine oils was less in the LPG engine than in the diesel engine.
    3. The C oil (one of trial manufacture) was recognized to be most suitable for the LPG engine.
  • 小中 俊雄, ビュックレ W. F.
    1968 年 30 巻 1 号 p. 5-12
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
    This study was conducted to analyze by application of similitude theory the slip-sinkage phenomenon in a clay soil using grousered plates. Seven unpowered rectangular grousered plates were designed with propotional lengths based on similitude model theory.
    Fifteen variables were arranged into dimensionless pi terms according to the Buckingham Pi Theorem:
    Z/y and H/pl2=F(b/l, h/l, λ/l, y/l, v2/gl, α, c/p, c/dl, φ)
    for set 1, and
    Z/y and H/pl2=(b/l, h/l, λ/l, y/l, v2/gl, α, q/p, q/dl)
    for set 2.
    The tests were conducted on a movable soil bin in the Model Tillage Laboratory of the Department of Agricultural Engineering, Iowa State University.
    The conclusions are the following:
    Slip-sinkage increased as vertical pressure increased, but was not signiificantly affected by the rate of slip.
    The correlation between sinkage Z and distance of horizontal movement y was shown in the following equatcon: Z=Kluyl-u (K and u are constant, 0<u<1) Sinkage in soft clay was larger than in hard clay soil, but slip-sinkage in soft clay was less significant than in clay soil.
    The draft pi term H/pl2 increased slightly as the slip rate increased, but was not significantly affected by the variation of vertical pressure.
    The correlation between the distortion factor (β=π9m9) and the prediction factors (δs1a1am, δa1b1bm) are shown in the following equations (Table 9.)
    δs1.46 when π6=0.00073, π8=0.70
    δs0.442 π6=0.00073, π8=0.35
    δa0.434 π6=0.00073, π8=0.35
    δa0.181 π6=0.00073, π8=0.18
    and so on.
  • 川村 登, 増田 康雄
    1968 年 30 巻 1 号 p. 13-18,12
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
    (1) Experimental studies on three centrifugal fans and some impellers as shown in Tab. 1 are done, to get the fundamental data to design duster. The electric dynamometer was used to drive the fans for the measurement of the input power. The pressure was measured by means of the JIS method.
    (2) As for the number of blades, the pressure coefficient of 18 blades is better than 12. The former is suitable for the boom duster, because it needs higher static pressure; but needs larger power.
    (3) The larger the outlet angle of blade is (for-ward blade), the higher the pressure coefficient. Therefore, the large outlet angle blade is suitable for boom duster; but needs larger power. The efficiency is not so much affected with blade angle.
    (4) The space between the case and the impeller did not give so bad influence as mentioned in literature, on the contrary, gave a little good result. It is necessary for the good performance of fan that the static pressure distribution in scroll does not change abruptly.
    (5) The choke of tube in bend gives the drops of the efficiency and pressure.
  • 川村 登, 山下 律也, 並河 清, 池田 善郎
    1968 年 30 巻 1 号 p. 19-23
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
    Small combine with self-feeding thresher, which has chain conveyor feeding straw along the cylinder axis and of which cylinder beats the ear part of straw, has many features. We measured the power requirements of the self-feeding thresher and obtained the following power requirement characteristics of it.
    (1) Observing the cylinder torque fluctuation when one sheaf was fed, it was found that the threshing action was finished before one half of cylinder length.
    (2) The threshing power requirement for the continuous feeding was about 70% of the sheaf feeding. It is favourable to feed continuously for the combine.
    (3) When one sheaf of green rice was fed, cylinder power requirement was relatively high. It rated to 60% of the total power input.
    (4) Power loss was considerably high, because of the slippage of V-belts.
    (5) Cylinder power requirement for dried rice was about 1/2 of for green rice.
    (6) The relations between feed rate and power requirement were linear for both dried and green rice.
    (7) For the threshing of one sheaf of green rice with the increases of the sheaf weight and the revolution of cylinder, the cylinder power requirements largely increased; but for the dried rice they did not so largely increased.
  • 山下 律也
    1968 年 30 巻 1 号 p. 24-28,41
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
    In order to dry forage, it needs to clear drying characteristics of lamina, petiole, peduncle and stem-and-calm which compose the forage.
    To satisfy this purpose, the tests on drying speeds and drying characteristics for grass parts were conducted for Renge and Italian ryegrass when the cutting length and the heating temperature were varied. Obtained results were as follows.
    (1) The moisture is much in stem-and-culm, and less in lamina just after harvesting.
    (2) The drying speed for each grass part is in order of lamina, petiole, peduncle and stem-and-culm. The relation of moisture content to drying time is linear when it is plotted on semi-logarithmic graph, and expressed by a variant exponential equation.
    (3) The drying speed of whole forage is synthesized by the per cent of each grass part and it's drying speed, and the mean drying speed of forage is dominated by the stem-and-culm because it is the main constituent.
    (4) The drying speed for cutting length is dominated by a cutting area per unit weight, and the shorter it is, the faster it dries.
    (5) As a cutting face unfolds outward and a evaporation area increases while drying, the effect of cutting enlarges.
    (6) To consider the drying speed for the heating temperature, the evaporation at a long cutting length is promoted by means of raising the temperature.
  • 松尾 昌樹
    1968 年 30 巻 1 号 p. 29-34
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
    From the experiments of the compression and wafering of hay or pasture (ladinoclover and orchardgrass) by the piston and cylinder type compression tests, the following results were obtained:
    1. Some sap ran off and the compression force requirements increased steeply when the final density of hay exceed over a limit.
    2. The characteristics of compression of hay or pasture were just like powder, and the following linear equation was obtained in relation between σ and σ/ε,
    σ=a+bσ/ε
    where σ is stress, ε is strain, a and b is constant.
    3. The maximum strain value of 23.5% moisture contents ladinoclover and 19.6% moisture contents orchardgrass were 0.8 and 0.808, in each sample, at this time the stress increased infinitely.
    4. The compression stress p for the equal strain value of orchardgrass were larger than that of ladinoclover, perhaps because the more fiber content and stronger stiffness of the former than the latter.
    5. The compression ratios of samples were 4-6 at a low moisture contents and 3-5 at a high moisture, but the difference of the compression ratio between ladinoclover and orchardgrass was very little. They increased linearly with increase of final dry weight density ρd.
    6. Pasture and hay showed rheological characteristics.
    The degree of stress relaxation increased with increase of sample moisture contents and that of orchardgrass was smaller than ladinoclover and disappeared after about two minutes.
    7. The compression force P increased exponentialy with increase of final dry weight density ρd, which of orchardgrass was larger than ladinoclover at low ρd, but their relations were inverted at high ρd.
    8. The compression force P and stress P increased as the height and volume of the formed wafer increased if sample moisture, ρd and diameter of formed wafer were equal, with the exception of high moisture samples.
    9. When the kind of hay, moisture contents, ρd and forming height were the same, to decrease the diameter of formed hay gave an increase in the compression stress p, and the difference of compression stress between rations diameters increased as ρd increased; therefore, it was supposed that the ratio of friction between wafer and cylindrical chamber wall was relatively large.
    10. As for the same kind and the same moisture content of hay, the force P requried to compress from a certain initial volume to a certain ρd decreased with the decrease of the diameter, especially in case of low moisture contents, therefore, it was sujested that the slender forming of hay is desirable from the view point of the power requirements.
    11. The Compression force P was constant or reduced as the forming height of hay increased at a high moisture contents.
    It was considered that the facts in the above three items depended on the rheological characteristics and ununiform compression of hay.
  • 中馬 豊, 村田 敏, 岩元 睦夫
    1968 年 30 巻 1 号 p. 35-41
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
    The authors designed the laboratory scale installations of room cooling and forced-air cooling, and the characteristics of the cooling rates of NATSU DAIDAI in some packages were studied in various conditions, i. e. stacking pattern, vent-opening and the rate of air flow. Results obtained were as follows:
    (1) The half cooling time of NATSU DAIDAI located in the center of standard carton was 10.8hr, for room cooling and 6.3hr, for forced-air cooling. The irregularity of the cooling rate for room cooling was smaller than that of forced air cooling. (Fig. 2, 3)
    (2) The effectiveness of vent hole was remarkable for forced-air cooling. (Fig. 2)
    (3) The cooling rate of forced air for lidless carton was very large, especially, when the cold air was blasted to the exposed NATSU DAIDAI. The half cooling time of NATSUD AIDAI located in the center of box was 1.3hr. (Fig. 4)
    (4) It was not so effective for the purpose of cooling to leave wide space between the cartons. compared with narrow one (Fig. 5)
    (5) The slopes of cooling curves in non-vented carton were parallel (Fig. 6)
    (6) It is necessary to pay following attentions in the cutting of vent hole on the carton. (Fig. 7, 8, 9)
    1) The vent hole should be bored in the perpendicularly plane to the forced air.
    2) Vent hole Should be bored in the lower part of the plane
    3) The area of vent hole of 5% is large enough 5 percent from the point of cooling.
    (7) Vented carton is better from the point of cooling compared with non-vented carton accompanied with highly increased air flow. (Eig. 10)
  • 中馬 豊, 村田 敏, 早川 功
    1968 年 30 巻 1 号 p. 42-44
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
    The pears in carton box on vibrator being asumed to be a Voigt-body rod atached to a foundation that vibrates the rod axially, the following differential equation and boundary conditions are derived:
    2u/∂t2-gγ/ρ∂2u/∂x2-ηg/ρ∂3u/∂t∂x2=Aω2cosωt (1)
    Stress=∂u/∂x=0 where x=λ (2)
    u=Acosωt where x=0 (3)
    where t: the time (sec), u: the displacement of the point in the vertical direction (m), x: coordinate in the vertical direction (m), g=9.8m/sec2, ρ: the density (kg/m3), η: the viscosity of the pears (kgs/m2), A: the amplitude of the vibrator (m), ω: the circular frequency of the vibrator (sec-1), γ: the elastisity of the pears (kg/m2), λ: the effective depth of the carton box (m).
    Using this solution, the elastisity and viscosity fo the pears are both calculated from the acceleration measured by the accelerometers in the pears (TABLE 1).
  • 竹田 策三
    1968 年 30 巻 1 号 p. 45-46
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
  • 1968 年 30 巻 1 号 p. 47-49
    発行日: 1968/06/01
    公開日: 2010/04/30
    ジャーナル フリー
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