(1) Two dimensional curve of plow-body is approximately represented by a sort of plane screw curves, that is r=r0et(φ-α) where, r, r0 are radius of curvature at any point of the curve and at share point respectively, φ, α are tangential angle at any point and at share point, and b is a constant. (2) A curve decided by one const. b will be called simple curve. The radius of curvature of this curve simply increase or decrease, and is constant when b is O. (3) When radius of curvature of a curve increase from share point to connecting point, then decrease from connecting point to end of breast, two const. b1 and b2, will be necessary to determine this curve. It will be called connected curve. (4) By calculation of example, relations between b or b1 and r0, r1, r2, b2 are shown in Fig. 2 and Fig 3. (5) These constants are measured about real Japanese plows. The curve of a plow is neare simple curve and that of six plows are almost connected curve. (6) Limit of radius of curvature at share point is decided by strain limit of compression side of curved fullow. For example, this is 45cm for Japanese common plow and 40cm for high breast plow.
The mounting methods of the tillage implements to the garden tractor and power tiller, such as fixed mounting, swing plow and hitching with flexible system, are studied mainly concerned to the traction and stability. The weight transfer of garden tractor with fixed mounting, is shown in Fig 2. To increase the traction, in case of the bihind mounting, l, a and RL make smaller; and W, RV larger. (Fig 1). The power tiller is a special case of the mfixed ounting. Wit hthe rotation of the tins R varies cyclicly, therefor, the weight transfer varies with some frequency; when R increases, D or the torque of the drive wheel decreases, and the power consumption isuniformlized (Fig 3). On the swing plow, the vertical landside force varies itself and makes the plow stable. If the hitch is located forward of the drive wheel axis, the traction sta bility is positive. With the flexible system hitching, the plow rappidly reaches its max. depth. and the stabilities of the traction and the depth are fairly good.
Surveying the draft resistances of the current tractor plows and disk harrows for soil-improvement use, in the different types of soils-heavy clay soil, clay-loam and volcanic light sandy loam or gravelly soil, we obtained the following results. i. e. 1. The specific resistance of subsoil-plow is influenced by the type of soil, it appears 0.304kg/cm2, in dry heavy clay soil 1.640kg/cm2, and in clay-loam or wet heavy clay soil a little above 0.7kg/cm2. 2. The specific resist. of layer-mixing plow, a variety of deep plow, appears 0.414kg/cm2 in volcanic gravelly soil. 3. If the sizes of disk harrows are similar, their draft resistances are nearly equal regardless of the types of soils described above. It map be required about 550kg. with the standard disk harrow -18″ diameter, 32 disks -and about 700kg. with the large disk harrows for soil-improvement use -20″ -26″ diameter, 10-20 disks. 4. In general, the specific resist. of the current disk harrows are in the range of 0.1-0.2kg/cm2, however 0.14-0.2kg/cm2 in heavy caly soils and 0.1-0.14kg/cm2 in volcanic soils. 5. In order to select the current implements appropriate to the tractor, we have surveyed the slip increasing rates of tractors caused by the draft at the even fields, before and after plowing, in the different types of soils. (vid. Fig. 1, 3).
I measured weights of the scattered soil, traction power and speed, by useing the wheel type soiler machine. And I knew as follows; (1) The wasted soil was constant at every speed, by useing with them, it was measured 28% of the total weights of soil. (2) The scattered soil is the maximum at 0.9m/sec, the traction power is directly proportional to the total weights of soil, the efficiency of traction power is the maximum at 10m/sec, the traction power per unit soil is the maximum at 7kg. (soil hardness) (3) y: weights of soil x: soil hardness, then y=6.54971-0.6253x y: traction power x: soil hardness, then y=88.184×0.7182x As this result, best useing conditions of the Boiler machine are; peed=0.8-0.9m/sec soil hardness=7kg.
Owing to know the stability of power tiller, we must be research the position of centre of the gravity, at the beginning. If we have inclined the machine until it shall be balanced, in the front and in the side, we can surely get the center of gravity. The balancing point in the side, thats showing Fig. 1 be able to express in the formula of Y=A sin X+B. In this formula, Y is the weight that is acting on the handle, X is the plate angle of the tiller, A shows the inclination of the formula, and B shows the weight of handle on the plate angle is in parallel with the horizon. In several power tillers, A of the Japanese tiller is largest than the other, therefore this tiller is difficult to drive than the other machine on the slope. When designning the power tiller, we must be decide the balancing weight of each parts as near as the formula that is most suitable on the stability, Y=1.2 sin X.
To measure the vibrations at the handle of the power tillers in field operation, we designed and constructed a small moving magnet type vibrometer (accelerometer) which consists of a pick up, amplifier and oscillograph. The pick up consists of a permanent magnet pendulum, coil and damping plate (see Fig. 1). The natural frequency of the magnet pendulum is 21cps. The overdamping is given by the damping plate and the damping oil filled in the pick up case. The size of the pick up is 66×54×54 (mm) and its weight is about 500g. The oscillogram (Fig. 3) of the vibration of the pick up gained by the vibration testing machine means the wave is the acceleration curve. The characteristics curve of this vibrometer is shown in Fig. 4. The performance of this vibrometer shows a good result when the acceleration is rapid, but it is not good when the acceleration is slow.
The corrosion behavior of chromium steel, stainless steel, cast iron and bronzes in each dilute moving solution of agricultural chemicals, such as lime sulphur compound, nicotine sulphate, uspelum and niccarine were studied. And the relation between the amount of corrosion and the corrosion time was clarified for each metallic materials to agricultural chemicals respectively.
We studied on the most effective and economical spraying method with power sprayer for pest control. The boom which we used in this experiment was a pipe with 10 spray-nozzles. Each nozzles were placed at interval of 11cm and their sizes were 0.8mm in diameter. The boom was moved by the equipment shown Fig 1. The results were as follows: 1) When the height of spraying (H) from the top of plant was lower than 40cm, the adhesion of chemicals was too much and ununiform, but when it was heigher than 40cm, the adhesion was decreased. In the case of the height in 40cm, we had the best result. (Fig. 2) 2) The speed of spraying (s), that is quantity of spraying chemicals, must be heigher than 77cm/sec. When it was lower than 77cm/sec, the quantity of spraying chemicals increased, but the increasing ratio of adhesion reduced. (Fig 3) 3) As the pressure of spraying (P) became higher, the adhesion did not increase so large as expected from the increased quantity of spraying chemicals. It's effect of pest control was smaller than the effect by the height and speed of spraying and the structuce of boom. (Fig 4) 4) The adhesion increased in proportion to the growth of rice plant. (Fig 5)
The author had the several cutting tests on a small type silage cutter, which revealed the following facts remarkably to reduce the required power. 1. As for the cutting mechanism, it is better to cut from the inner side of the shear plate to the outer side. 2. By increasing the affixed angle of the cutting knives, feed material can be free from being pushed towards the back of the knives or the wheel arms, consequently the required power is greatly reduced. 3. Difference of the flywheel rim weight is so little concerned in the required power at the constant load. It is necessary to be driven with the constant number of revolutions by keeping the belt from slip. 4. Difference of the blade angle only little influences the cutting resistance. Sharpen, therefore, the knife edge, even if the blade angle be larger, and it will show the better result than in the case of a dull blade with a smaller angle.
One of the rotary mower that was named E-53-2 type was made under tieal by us. And researched the effect using it in milkvetch and soybean for silage. 1) Wheels of machine were propelled by driven rubber drums. —this is the different point to E-53-1 type, mower. —See fig. 2. 2) We applied two different size rotary cutter (K-type or E-type) and set several types of vertical vane on 4 arms of cutter (a, b, c, d, 1, 2, 3, 4)-See fig. 1. 3) We got the better results as the diameter of cutter, and the height and length of the vane became longer or heigher. (See teble 5) 4) We have got selfconfidence that we could harvest sufficiently thick milk vetch and soybean into regular windrows. (See fig. 2 and 3). But we could not researched next items in this study, so we want to continue this study. 1) How much _??_ is consumed to havest grass or milk vetch by this machine? 2) What is the most effective shape of cutter?
In the first report, I described about the machnism of apparatus and the progress of reserch. In this report, I should like to analysis dynamically the operation of the apparatus in order to confirm the effect and investigator elements for the design.