The authors studied on the load factor of small type tractor to get data for deciding the strength of body. Therefore, we produced the accelerometer to determine the load factors and measured the accelerations of tractor body under various speeds, tillage-depths, and speeds of rotary shaft. The load factors were 1.5-4 and they were larger at the front of body. Thus, the great stress magnitudes appeared between the wheel axis and the hitch.
In order to know the force, stress and displacement appearing at every power transmission system of a power tiller, one of the widely used models in Japan, new measuring devices have been made. All transitorized mobile part of these devices which were attached to a power tiller operated in the farm field, was designed and constructed without making any change or destruction of the power tiller's own construction. Torque at the rotating tilling axis and the right and left wheel axes was measured using wire resistance strain gages attached to the principal strain directions of them. Connections between the rotating axis and frame of the tiller were made with noiseless silver to silver contact slip rings and brushes. Three accelerometers of the type of wire strain gage were attached around the gravity center of the tiller for three independent directions, one for the direction of movement and the others for perpendicular to the first. Distance and velocity were obtained by integrating the accerelation with electronic analog computer under real time operation. Tension at the link plate of the moving roller chain was also measured using wire resistance strain gages. Non-touching pitch counters of the roller chain sprockets were constructed for observing their angular displacement, angular velocity, angular acceleration and ununiformity of their rotation. All signals obtained from the mobile parts were preamplified and transmitted through the cables about 45 meters long to the laboratory where amplification, discrimination and recording were made. Every power supply for these purposes was fed from precisely regulated electronic voltage stabilizer. Recording was made using electro-magnetic oscillograph of 12 elements, direct writing recorder of 6 elements and 2 channels of magnetic tape recorder. This simultaneous recording made it possible to display the phase relation among these signals. Experimental results and analyses will be reported successively.
The conditions of the divisions of working units for tillage by a tractor (15-18Hp) were compared from the viewpoint of working efficiency, especially in turning operations, and following results were obtained. 1. As to various kinds of turning operations, the relations between turning distance and turning time are expressed in such linear equations (Tab. 1.), that total turning time can be calculated as the sum of arithmetical series. In the turning distance less than two times of the minimum turning radius of a tractor, the bottle shaped method is most efficient. 2. The effects of various conditions of the working unit divisions on plowing efficiencies are clarified (Fig. 2-4) based on four equations ((8)-(11)). Those equations were introduced from fields experiments of going and returning metod of plowing accompanied by bottle shaped and U shaped turning. As to rotary cultivation, the result is shown in Fig. 5. 3. For the improvement of working efficiency, the increase of the length-width ratio of a unit division was proved to be more efficient than the enlargement of area of a division, in either case of plowing or rotary cultivation. 4. To keep the time loss by turning operation under 10 percent of total working time, the length-width ratio of a unit division should be determined not less than 6 in plowing and 4 in rotary cultivation.
The present study wass designed to make clear the difference in the freezing condition between panbroken and untreated soils. The investigation which is a continuation of the previous report (Journal of the Society of Agr. Machinery, Japan. Vol. 22, No. 3, 1960) was carried out at “Bekkai village” in Hokkaido in 1960. The results of the investigation were as follows; Several types of soil freezing could be found, according to the soil and climatic conditions. 1. Results of the investigation at “Harauchi” plot; For the untreated soil, the ice layer formed by compact accumulation of thin ice plate could be found under the upper layer with 4-8cm. depth which consisted of only frozen soil without distinct ice crystal. For the treated soil, on the other hand, the ice layer under the upper layer consisted of the alternate layers of thin ice plate and frozen soil. The density of this layer of the treated soil was lower than that of the untreated soil. These facts showed that there was the difference in permeability of rain-water before beginning of severe cold weather between treated and untreated soils. 2. Results of the investigation at “Momono” plot; There is no snow-accumulation by strong wind at this plot. For the untreated soil, the frozen soil of 9cm. thick existing under the upper layer of 17cm. was mixed compactly with lots of ice blocks of 1 or 2mm. diameter. For the treated soil, however, the ice blocks could be found in 1/3 of the upper part of the frozen soil of 8cm thick. Under-layer of these ice block layers also consisted of frozen soil. Although the ice plate of 1 or 2mm. thickness accumulated compactly in this under-layer with 6cm. depth for the untreated soil, the hole which was made by the chisel of pan-breaker could be found in the under-layer for the treated soil. Thus, the effect of pan-breaking appeared evidently in this case, too. 3. Results of the investigation at “Kudo” plot; This plot is a lowland between hills. There were two cases, A and B at this plot. A). The frozen soil with ice crystal in the subsoil was 13cm. thick (from 6cm. to 19cm. from surface) for the untreated soil, and it was 25cm. (from 5cm. to 30cm. from surface) for the treated soil. However, the density of the frozen soil of the treated soil was lower than that of the untreated soil. B). For the treated soil, the compact alternate of ice plate and frozen soil could be found. For the untreated soil, ice plate and ice block accumulated mutually. The density and thickness of the frozen layer of the untreated soil were higher than those of the treated soil. 4. Hardness of the frozen soil; The upper part of the frozen layer was as hard as concrete, and a pick was leaped up. However the hardness decreased gradually in accordance with depth increases.
This study was conducted to investigate the effects of pan-breaking on physical properties of soil and beet yield for the third year after pan-breaking treatment. This was done on the experimental field at Hokkaido University in 1901. The results were as follows; 1. Though there was not a significant difference in water content and porosity rate of soil between treated and untreated plots, the decrease of water spots on the soil surface indicated that the drainage effect of pan-breaking lasted for three years. 2. Soil hardness data were secured by the cone penetrometer. The equi-hardness curve shows that the chisel trace maintains its shape and softness in the third year after pan-breaking. 3. Pan-breaking treatment of soil gave increased top growth and moderately higher root yields of beet crop in the third year after treatment.
On the measurment of soil displacement, it is necessary to clear the characteristic of displacement of soil displacement measuring pieces, and its characteristic can be shown by the trusting ratio of them. The trusting ratio of soil displacement measuring pieces changes by the material, size and specific-gravity of them, but we summarized as follows: (1) The authors have introduced the following equation to indicate the trusting ratio of soil displacement measuring pieces. The trusting ratio (%)=100-β×average deviation where, β is a coefficient that is determined by the number of divided stratums and the minimum value of scattering soil to divided stratums. (2) The trusting ratio of chalk-pieces are as follows: length trusting ratio 0.75cm 97.74% 1.5cm 98.17% 3.0cm 89.74% (3) There is some relation between the trusting ratio and the number of soil displacement measuring pieces. When the number of them increases, the trusting ratio approximates to characterestic value of them. (4) On the measurment, more than a hundred soil displacement measuring pieces is necessary.
The coating of seeds makesit possible to drop the seeds more easily and smoothly from the seed spout of planter. So the author made experiments on the coating method, coating machine, coating material and germination of the coated seeds. The results were as follows: 1. Two types of the coating machine, coating pan and tabletting machine were used. The coating pan was suitable for seeds of Beer barley, barley and wheat, and tabletting machine for comparatively small seeds like those of rape-seed, turnip and radish. 2. The author used talcum as main coating material, and arabicgum and gelatine as binder. 3. In germination of seeds there was no difference between coated seeds and natural seeds.
The influences of the abrasion of fan blower on its performance were investigated for 50 hours by dusting polishing powder instead of agricultural chemicals with knapsack mist-duster (Arimitsu-EDM) (1) The abrasion of fan-case is more severe than that of fan-blade. The amount of abrasion of fan-blade seemed to increase with time, while that of fan-case was distinguished between 10 to 30 hours. (2) The feature of abrasion of fan blade was observed every 10 hours. (3) Both the discharge(air flow)and the driving horse power of fan blade decreased with its abrasion. This tendency is especially remarkable in the former after 30 hours, driving at the revolution higher than 5000r. p. m. Fuel consumption (grips-h) increased with time. (4) The efficiency of fan blower declined for the first 10 hours, while it increased thereafter with driving time. On the influence of abrasion of fan blower on the performance, the decline of discharge should be taken care rather than its efficiency.
We made a self-propelled rice combine for trial. A four-wheel tractor (17PS) was rebuilt for its use, on which a conventional T-type header, separating units and an axial-type threshing cylinder were mounted. Specification Cutting width 1.5m (5 feet) Tractor engine horsepower 17PS Desirable ground speed 0.4-0.8m/s Net weight 1300kg In test, on paddy fields, we could get the intended results-unthreshed seeds, husked seeds, and power requirements for the cylinder were below 1 per cent, approximately 1 per cent and 2-3 ps respectively.
As shown in previous report, our experiments clearly indicated that plant surfaces were covered very extensively by using the water-dust and mist-dust mixed application methods. But in those experiments, we felt uneasy about effects of injury of applicated chemicals by the reason that covered surfaces were too extensive for plants. So, the injuries of applicated chemicals for the Japanese pear, the cabbage and the yam were investigated in the field experiments. And the results of those were as follows; (1) On the Japanese pear, when mixed chemicals of Bordeaux mixture and BHC dusts were applicated, those injuries were not occurred. But we found injury on the leaves only in the case of Folidol for the dusts. (2) On the cabbage, injury of applicated chemicals was not found at all. And in the mist-dust mixed application plots the damages by insects and diseases were less than those in the water-dust mixed application plot. (3) On the yam, injuries of applicated chemicals were not also occurred. The efficiencies of application work by mixed applicators were higher than those by power sprayers. (4) It can generally be said that we need not care about chemicals injury in using the water-dust and mist-dust mixed application methods. The working efficiency and pest control effects of these new application methods were good.