農業機械学会誌
Online ISSN : 1884-6025
Print ISSN : 0285-2543
ISSN-L : 0285-2543
32 巻 , 2 号
選択された号の論文の13件中1~13を表示しています
  • 芝野 保徳
    1970 年 32 巻 2 号 p. 87-95
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    The plowing and the rotary tilling tests were performed by using the walking tractor attached with the Japanese plow and the rotary tillage apparatus.
    The characteristics of the plowing and the rotary tilling were summarized as follows.
    Plowing.
    1) The draft resistance increased as the depth was increased, and there was no definite relation between the draft resistance and the travel speed.
    2) The torque of right wheel shaft was 1.2-1.5, times as large as left wheel shaft.
    3) The dynamic weight on the driving wheel decreased as the draft resistance was increased, while the dynamic weight on the heel of plow increased as the draft reistance was increased.
    4) The tractive power coefficient became maximum of 0.35 at the coefficient of traction of 0.50 (the travel reduction 0.32) and the tractive efficiency became maximum of 0.53 at the coefficicient of traction of 0.32 (the travel reduction 0.21).
    Rotary tilling.
    1) The rotor shaft torque increased as the depth and the travel speed were increased, while it generally decreased with an increase in the rotor speed.
    2) The wheel shaft torque decreased as the depth and the travel speed were increased because of propulsion by tines.
    3) As the wheel shaft power was nearly zero, about 95% of the main shaft power was consumed in the tilling parts.
    4) It was recognized that the dynamic weight on the depth adjusting wheel was heavier than the static weight on it, while the dynamic weight on the driving wheel was lighter than the static weight on it.
  • 吉田 富穂, 武田 太一, 松見 高俊, 寺尾 日出男, 伊藤 和彦
    1970 年 32 巻 2 号 p. 96-103
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    1) Since three-point linkage dynamometer reported in the previous paper had a mechanical failure between each pin dynamometer and three-point link, its improvements shown in Fig. 1 was made.
    2) As the results of their improvements, each pin dynamometer measured loads above 300kg with an accuracy of within ±3%, while prior to improvements it messured above 500kg with an accuracy of within ±5%.
    3) Calibration curve and measuring accuracies were investigated by applying static load on three-point linkage dynamometer, using calibrating apparatus and methods shown in Fig. 2, 3.
    4) The results are approximately summarized by the statement that the dynamometer, limited to tractor using a free linkage, will measure loads above 300kg with accuracy of within ±3%.
    5) The investigation of three-point linkage dynamometer compared with the trace tractor method of draught measurement was carried out.
    6) On the concrete test track condition, the draught obtained by using a strain gage dynamometer minus that by the three-point linkage dynamometer was approximately equal to the rolling resistance of the tractor. The effect of towing speed and draught was not recognized.
    7) In relation among the draught of the three-point linkage dynamometer L2, and top link horizontal force T, and lower link horigontol force supperposed L+R, the ratio T/L2 and L+R/L2 were 6% lower than, and very similar to, the results obtained from the graphical analysis (Fig. 12)
    8) On firm loam and sandy loam soil test track condition, draught of the implement obtained were from 200 for 1150kg, by changing the depth of heavy duty cultivator. As the results, draught force L1 (trace tractor method) and L2 (three point linkage dynamometer) were neary equal. (Fig. 14) The effect of towing speed and draught was not recognized.
  • 岡本 嗣男, 川村 登
    1970 年 32 巻 2 号 p. 104-110
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    To study the characteristics of the sensing device of torque on a hydraulic driving system, some experiments and analyses have been done.
    (1) The torque sensing device has a coil-spring by which oil pressure is transformed to spring displacement.
    (2) Steady state characteristic of sensing system has a relationship of linearity between oil preesure and spring displacement.
    (3) Transient response of the spring displacement to the oil pressure is very good and its time lag is very short.
    (4) Steadily, the number of revolution of a hydraulic motor is almost constant under a setting pressure of a relief valve.
    (5) A system of velocity of rotation of hydraulic motor to torque constitutes a disturbance control system. Its transient variation is little and becomes smaller rapidly.
    (6) The dynamic characteristic of this system is under great influence of the inertia momentum of load and the capacity of actuator. To get a good responsability for the system, it is important to use the hydraulic motor which has a capacity suited to a value of inertia momentum of load.
    (7) The gain of the system is low on high frequency and the response is relieved from the impactional input. This is a merit of the hydraulic driving system.
    (8) It is easy to find the value of torque on hydraulic system by a spring and the signal is transmitted easily by the pilot pressure. This sensing system is very simple and has little inertia force. And so, the response characteristic is good and stable.
  • 松山 龍男, 川崎 健, 藤岡 澄行, 前岡 邦彦
    1970 年 32 巻 2 号 p. 111-116
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    The static side-overturning angle of 4 wheel tractor is expressed as functions of the location of gravity, tread, wheelbase, rotating angle of front axle around the center pivot and so on (Eg. (6), (7)).
    The results derived from these functions are summarized as follows:
    (1) The critical angle increases as the height of center of gravity decreases, the tread increases, and the center of gravity transfers rearward.
    (2) The critical angle increases as the location of hinge point connecting the front axle with chassis becomes higher.
    (3) Reduction of the rotating angle of front axle is recommended for safety operation, as it can prevent unstability caused by mounting of implement.
  • 梅田 重夫, 毛利 建太郎
    1970 年 32 巻 2 号 p. 117-122
    発行日: 1970/09/01
    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 movement of suction and discharge valves, and a relation between each valve and pumping performance of power sprayer.
    The lift of each valve was measured by the variation of inductance
    The experiment was performed about the each valve having the three kinds of spring varied the spring constant.
    For the actual operating of power sprayer, the movement of suction and discharge valves, the pressure in cylinders and suction port, were measured. In order to calculate the volumteric efficiency and pump efficiency, the discharge flow, the discharge pressure and rotational speed were meeasured.
    The following results were obtained.
    1. The movement of suction and discharge valves, the pressure variation in cylinders and the fluctuation of suction pressure per one revolution were shown in Fig 3.
    2. The valve delays in closing and opening were found as a rotational angle of crank shaft. On each valve, the valve delays increased with the spring constant of valve spring was the smallest, the valve delay was the greatest in each valve.
    3. On the discharge valve, the maximum valve lift increased with the increase of rotational speed.
    4. The volumetric efficiency and pump efficiency were shown in Fig 8.
    When the spring constant was the smallest, the volumetric efficency was dropped in the range of rotational speed above 600rpm.
  • 松尾 昌樹, 牧園 晴充, 太田 善三郎
    1970 年 32 巻 2 号 p. 123-128
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    From the experiments at rice harvesting of three row type walking grain binder, the power requirements of each part, which were measured by the improved equipment, were as follows:
    (1) The relations between rice feed rate and the mean torques of each part were the same as those in wheat. The binding unit torque was linearly increased with the increase of the weight of a rice bundle, and it was independent of the feed rate.
    (2) The maximum torques of each part of binder were about 2-2.5 times of respective mean torques.
    (3) The rice feed rate was about 2.5 times of wheat. When the straws were upright (straw inclination angle θ was equal 90 degrees), the mean torques of pick-up unit, cutting unit and driving wheel were almost the same as those in wheat, and the torque of cutting unit and pick-up unit was smaller than that of other unit.
    (4) The torque of pick-up unit, when the straws inclined backward (θ<90°), was smaller than the one when the straws inclined ahead (θ>90°), the order of magnitude of torque, when straws inclined, was as follows: (θ<90°)>(θ<90°)>(θ=90°). It was possible to reap rice straws inclined in the range of 30°<θ<150°. They almost couldn't be picked up when θ=180°, but almost could be picked up when θ=0°, though many grain losses grew.
    (5) In the case of rice harvesting, the torques of conveyor and binding unit were 2.5-3 and 5-6 times of wheat, respectively, and the weight of a bundle was also larger than wheat. It was considered that these large torques were due to the feed rate, the weight of a bundle and the friction of paddy and unsuitable timing of binding unit and others. Therefore, the binding unit should be improved in future.
    The total power requirement at the second gear was small and economic compared with at the first gear except that the feed rate was low.
    (6) Even in the case of upright straws (θ=90°), the total power requirements, which were 2.7-5.9 PS at the first gear and 3-4.6 Ps at the second gear were nearly full load for the engine. and the binding unit power at binding reached up to 66-76% of the total power.
  • 中川 健治, 堀部 和雄, 佐藤 純一
    1970 年 32 巻 2 号 p. 129-134
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    1. The movement of tea-leaves fed in the thrower was analyzed and the formulas of their movement courses, discharge speeds and angles were obtained. The movement courses at several throw positions and with primary speeds were calculated by using these formulas, which were shown in Figs. 2 and 3.
    2. Observations of the tea-leaves flowing in casing at several throw positions and speeds revealed that the relative position between inlet and outlet had a strong effect on the movement course of tea-leaves and suction. It seemed that there were a suitable positions which, after observations and mathematical analyses, were obtained as in Fig. 4.
    4. If the number revolutions required (N) of impeller is approximated by formula (24), the value of ξ (theoretical revolution number/revolution number required) in this formula is 0.4-0.5.
  • 梅田 重夫
    1970 年 32 巻 2 号 p. 135-139
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    This study was performed to carry out the separation, drying and conveyance of grains by fluidization. The soy bean, red bean, unhulled rice, brown rice, barley and rape seed were fluidized by air and the air distributors were used the fabric (felt) and wire screens (150, 50, 30 and 10 mesh).
    As the results, the minimum fluidization velocities of these grains were 0.6-1.7m/sec and the velocity of large graing was larger than small ones.
    The fluidized states varied with the size of the grain, the kind of the distributor and the initial bed height and the phenomena of the channeling and slugging occured under particular conditions.
    As grains were not fluidized uniformly in these experiments, further investigation is needed to understand these phenomena clearly before applying the fluidization to the separation, drying and conveyance of grains.
  • 石橋 貞人, 小島 孝之, 伊東 秋人
    1970 年 32 巻 2 号 p. 140-144
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    In this experiment, cooling, cold air drying and storage of deep bed baley (NIRASAKI No. 5) were made without interruption.
    1. The sample weight was 250kg. In During cooling and drying, the cooling air temperature, the relative humidity and the air flow rate were 10-13°C, 80-85% and 2-3m3/min., respectively. During storage, the daily mean values of air temperatures, relative humidities and flow rates were within the limits of 10-16°C, 70-90% and 0.5-1.0m3/min., respectively.
    2. Time required in cooling the grain from 20.5°C to 8°C was 25 hours. The drying time of the grain from 20.5% to 10.5% m. c. was 264 hours (11 days).
    3. The inlet air temperature and relative humidity were influeced and changed due to the change of external atmosphere conditions, because of the unsufficient heat insulation of the storage bin and pipes. Therefore, the equilibrium moisture content became dynamical and resulted in inconsitency with the equilibrium moiture content in steady state
    4. The storage term was 69 days, during which grain moulds were not detected.
    5. In the 69 day storage the grain moisture content decreased 1% and the germination ratio decreased 0.6%.
  • 小島 孝之, 石橋 貞人
    1970 年 32 巻 2 号 p. 145-149
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    Apples (KOKKO, KOGYOKU, INDO), pears (NIJISSEIKI) and peaches (HAKUHO) were test ed for their mechaical properties. The results were as follows:
    1) If the grade, kind, variety, quality, growing conditions, harvesting time and the handling methods after the harvest were the same, the rupture point of each agricultural product was almost equal (Fig. 3).
    2) The handling method of agricultural products after harvest, the method of transportation such as by cold storage car or normal car; severity of vibration in transit showed an effect on the rate of post-maturation and softening of the products.
    3) If the agricultural products had the same storage conditions, temperature and humidity, its creep deformation and unrecovery deformation tended to increase respectively, on account of the postmaturation and the softening.
    4) Softening rate of products tended to differ on account of their harvesting time.
    5) In general, agricultural products have different strength at various times after harvest, therefore the relative strength among varied agricultural products should be determined at either the harvest time or eating time.
    6) The change of damage volume by the falling impact tests was not observed during 5 days after the test.
  • 清水 幸夫
    1970 年 32 巻 2 号 p. 150-155
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    Changes in the void space within a tobacco leaf during curing were studied.
    1. The effect of various drying parameters on the void of the tissue was considered from the viewpoint of the volume balance.
    The following equation was obtained.
    εd=1-a (1-εg) /k
    where:
    εd: void of the dried leaf
    a: coefficient of real volumetric shrinkage
    k: coefficent of apparent volumetric shrinkage
    εg: void of harvested leaves
    Among these parameters, k was considered to be the most changeable one
    2. The void of the tissue was examined with both harvested and ordinarily flue-cured leaves. In the case of harvested leaves, the void was calculated from the known data on the volume percentage of the intercellular space and an assumed specific gravity of tobacco leaves. The calculated values were found to be 0.25 to 0.4 and they were greater in the lower leaves than in the upper ones. The void of the cured leaves was obtained by the measurement of their apparent and real densities. The values were found to be within the range of 0.23-0.6, and also comparably greater in the lower leaves.
    By comparing harvested leaves with cured ones, it was revealed that the void of the lower leaves considerably increased during curing although that of the upper ones did not show any change.
    3. Based on the above results, three methods of curing to improve the void of the leaf were examined. They were; 1) drying the leaf under tension load, 2) changing the rate of drying, and 3) freeze-drying of the leaf at the end of the yellowing stage of curing.
    In the method 1), the void of leaves was increased by 4% by applying the tension load equivalent to twice the shrinkage strength. Changing the rate of drying, however, did not give any appreciable effect on the void of the dried leaves. In the method 3), about 20% or less moisture was initially removed from the leaves during the yellowing stage and then leaves were subjected to freeze-drying. This procedure increased the void of the leaves by 11%.
  • 永田 雅輝, 古池 寿夫, 岡田 芳一
    1970 年 32 巻 2 号 p. 156-159
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    1) The authors constructed an experimental crack tester for unhulled rice. The tester consisted of (1) a source of light (1), (2) a sample unhulled rice box (3), (3) a light control board (4) and (4) a dark room (5) (Fig. 4). The light control board is the most important part. Therefore, three kinds were tried. These were as follows; (1) Slit slide type, (2) Pin hole slide type, (3) Pin hole fixed type (Fig 5).
    2) The procedure of testing was as follows: put fifty grains of unhulled rice into the sample unhulled rice box, then set them on the light control board. Then switch on the light and slide from the right to the left the sample unhulled rice box on the light control board, and check shadows that will appear at the cracks. Thus a user can tell cracked rice from uncracked one.
    3) The percentage of detection by using this tester was on the whole 83%, and that of pin hole fixed type was from 90 to 98%. If a user masters, the method of using the tester, the percentage will be more than 90%.
    4) The time reqiured to test fifty grains of unhulled rice was from 3 to 4 minitues. Namely, the necessary time of this tester is one-third, that of a crack tester for hulled rice usually needed. The most efficient light control board was the pin hole fixed type
  • 1970 年 32 巻 2 号 p. 160-162
    発行日: 1970/09/01
    公開日: 2010/04/30
    ジャーナル フリー
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