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Volume 41 (1979 - 198･･･
- Issue 4 Pages 533-
- Issue 3 Pages 351-
- Issue 2 Pages 191-
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Volume 41, Issue 2
Displaying 1-22 of 22 articles from this issue
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[in Japanese]1979 Volume 41 Issue 2 Pages 191-192
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (454K) -
On PV DiagramKazuo Sato, Kazuo Kido, Masamitsu Nakano1979 Volume 41 Issue 2 Pages 193-200
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThis paper deals principally with how to make the PV diagram theoretically, then the indicated mean effective pressure (IMEP) of the eccentric type engine was compared with that of the general purpose engine making use of this theoretical method.
The followings are the results:
1. IMET of the eccentric type was higher than IMEP of the general purpose engine. The relationships between the change of the factors of the engine and IMEP were as follows.
For example.
2. In case of changing a scavenging efficiency (which is equal to charging efficiency in case that relative charge is constant), IMEP was approximately in proportion to its efficiency.
3. In case of changing a crank angle at the maximum pressure, IMEP was maximum at a suitable angle after top dead center.
4. In case of changing a percentage that participate in combustion of a residual gas, if its percentage was much, IMEP decreased a little.
5. In case of changing air-fuel ratio, IMEP was maximum at the ratio, 13-14.
6. Under the process that PV diagram was made, the emission of gases etc. were also found.
For example, (a) the NO quantities were more than the case that the participation rate was small. (b) The NO quantities were approximately maximum at air-fuel ratio 16.View full abstractDownload PDF (1135K) -
Injection Timing and Pressure of FuelMitsuo IIMOTO1979 Volume 41 Issue 2 Pages 201-206
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe result of the past performance test of a small diesel engine using rape-seed oil as fuel showed no special abnormality. In the paper, analysis of exhaust gases (CO2, O2, CO), excess air ratio and engine performance with varied injection timings and pressures were discussed. The results were as follows.
1. Both light oil and rape-seed oil showed small amount of CO less than 0.2 percent and especially rape-seed oil had high combustibility.
2. Although increasing excess air ratio decreased exhaust-gas temperature, the exhaust-gas temperature in case of the rapeseed oil was lower than the light oil for the same load. The reason is that excess air ratio of the rape-seed oil is higher than the light oil.
3. Results of engine performance with varied injection timings and pressures were as follows.
1) For the injection timings at B. T. D. C. 10°, 8°, and 6°, the engine performances of the both light oil and rape-seed oil showed stability through injection pressures between 95kg/cm2 and 180kg/cm2.
2) In the case of B. T. D. C 14°and 12°, the brake thermal efficiencies for the rape-seed oil were higher than the light oil at 11/10 load at rated horsepower under 95kg/cm2 of injection pressure.
As the results, it was proved that the rape-seed oil was adaptable in wide range of injection timings and pressures.View full abstractDownload PDF (811K) -
Simulation of tractor motion and its applicationYasuo SHIBATA, Jun SAKAI1979 Volume 41 Issue 2 Pages 207-214
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe dynamic vehavior of small rear-wheel drive tractors attached with rotary tillers was mainly studied based on the equations developped in the previous report and some fundamental design equations were proposed. The results are obtained as follows:
1. The reduction of the tractor weight of 730kg by 10% caused the increase of the variation of the braking force about by 20% and the weight on the front and rear wheels about by 5%.
2. As long as the imaginary hitch point is located before the center of gravity of tractor, the influence of the differences of the horizontal locations of the point to the dynamic behavior of the tractor was small. The vertical location of the imaginary hitch point gave much influence to the weights on the front and rear wheels. Lower the location, larger the variation of the weights on the front wheels became. However, the maximum weights on the front wheels were almost the same.
3. The reduction of the rotational speed of the rotary axle led to the increase of the variation of the braking force and the weights on the front and rear wheels. This teans that much consideration have to be taken on the rotary blades arrangement when reducing the rotational speed of the rotary axle.
4. The influence of the difference of tractor weight distribution to the front and rear wheels and the tractor mass moment of inertia about a transverse axis through the center of gravity to the dynamic behavior of the rotary-tilling tractor was small.
5. The soil-bin test showed that the coefficient of braking force, which is the ratio of the braking force to the weight on the rear wheels, was about 1.0 as the maximum and decreased to about 0.55 after it reached to the maximum when the tractor walked out, On the other hand, the tractor was stable when the mean value of the coefficient of braking force was less than about 0.43.
6. The critical coefficient of braking force was defined to be the upper limit of the coefficient of braking force in the stable range for a tractor mounted with a rotary tiller and its numerical value was proposed to be about 0.45.
7. The design equation for the optimal weight of tractor mounted with a rotary-tiller was proposed. The variation factor of the coefficient of braking force as well as the critical coefficient of braking force plays the important role in the equation.View full abstractDownload PDF (1253K) -
(1) An analytical representation of blade curve as cut-in angle constantShotaro MORISHIMA1979 Volume 41 Issue 2 Pages 215-219
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESS1. An analytical difference between Pierce-in tine (so called Common tine) and Cut-in blade (nataba blade) was expressed by the equation (1).
2. The blade curve was analyzed through the equation (6) considering the cut-in angle γ is const. (Fig. 1). Some calculated examples were shown in Fig. 5.
For special cases, when the speed of rotary shaft u becomes zero, the equation (6) expresses the logarithmic spiral.
3. In case of u≠0 the tangential angle a can be expressed by the equation (7). (cf. Fig. 2)
4. The cut-in angle δ in operation will be the function of rotary angle θ, and it can be determined from the equation (10). (cf. Fig. 3)
5. As the Side blade has characteristics of Pierce-in tine, the transition part from Cut-in blade to Side blade will be obtained from the equation (9), in which γ=0. This shows the circle in which the center is located at (0, u/ω).
The patent dealing with the transition part (Kubota Co. etc.) can be considered as the special case of equation (9), where u=0. This is a circle of which the center is at (0, 0).
6. The section of Side blade consists of cylindrical surface, cut by any plane pararell to x-y plane, can also be expressed by equation (9).
The cut-in angle of the section under operation can be represented by the eqution (10).
For example, δ is around from -0°. 11 to -4°. -04, the negative sign means that the section has pierce-in effect.View full abstractDownload PDF (613K) -
Mathematical Model Representation of Distribution of Seeds on a Section of the Transportation Tube by Sent Pressurized-SystemMasaki MATSUO, Katsumi ISHIKAWA1979 Volume 41 Issue 2 Pages 221-228
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSSeeds were supplied into the rising tube passing though the bend by action of radical fan, and the seeds in the rising tube were influenced by the disorder of aerial current and the trajectory of seeds etc., and the seeds moved randomly by the collision with the flying seeds or the wall of tube. In this paper, the analysis of phenomenon such as floatation of the seeds in the rising tube were carried out statistically.
1. The collision of seeds were apt to arise when the transported volume of seeds increased at a constant aerial speed, and a part of seeds stayed by the normal line component which was directed outward at the bend of tube, and removed along the outside wall of tube, and distribution of seeds approached to a rather uniform dispersion on a section of the rising tube.
2. From the results of the large disturbance of aerial current, the distribution of aerial speed became uniform on a section of the vertical tube, therefore, the interval of seeds distributed on a section of vertical tube had a smaller extent of dispersion than that of the inclined tube.
3. The distribution of seeds on a given section of the rising tube was indicated as a exponential function of the number of seeds on a section where seeds floated at a nearly constant condition, and the experimental coefficient which could be obtained by the aerial speed, the transported volume and the shape of seeds.
4. Assuming that the seed is a sphere, the hypothetical elastic collision theory based on the law in terms of probability could be applied to the collision with the flying seeds or the wall of tube by using a spherical model, and the trajectory of floating seed was analyzed.
5. The process that the seeds floating on a given section of the rising tube distributed on the top of its section were characterized by random variable, excepting the phenomenon of the seeds distributed in the neighborhood of the base of tube.View full abstractDownload PDF (1186K) -
For Developing Self Feeding Devices of Rice Transplanting MachineHaruo EZAKI, Shotaro YUZAWA, Toshio KONAKA1979 Volume 41 Issue 2 Pages 229-242
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSAfter testing the effects of vibration on the deformation of rice seedling mat, it was cleared that the direction, frequency and amplitude of vibration remarkably influenced the deformation of mat. Also, the relationship between the feeding speed of mat at receiving plate and the shape and angle of the plate was reported.
Both the vibration test and the feeding speed test, evaluating some of the physical properties of seedling mat, could be used as basic data required for the design of the self feeding device of seedling mat.
A prototype of self feeding device of seedling mat using sequential automatic control was designed and the test results were reported in this paper, part II.View full abstractDownload PDF (2079K) -
Effect of Nozzle Loss on Water Jet and Coverage Property of Water JetMotonobu URA, Noboru KAWAMURA1979 Volume 41 Issue 2 Pages 243-250
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESS1. A loss coefficient of a solid cone nozzle for the high pressure type sprinkler became greater according to the increase of Re Number in the range under Rec and it had a peak near Rec. ζn was considerably affected by the contraction angle δ of a nozzle; namely ζn became less against the nozzle that δ was smaller regardless of the nozzle diameter. Considering an aspect ratio, when Dn was less than 2mm, ζn became smaller for the nozzle without cylindrical part because the pressure loss was caused by the swirl at this part of the nozzle, but when Dn was bigger than 3mm, ζn became greater for the nozzle with cylindrical part.
2. Accompanied air velocity ua by water jet stream was approximately expressed by a normal distribution, and the air velocity on the axis of water jet stream was shown by 2 kinds of exponential curves. A length of jet stream core was not varied by the difference of ejected pressure for the nozzle that Dn=1mm, but it extended with the increase of ejected pressure against Dn=2mm.
3. When a nozzle was fixed as the ejected angle became 12°, the maximum coverage distance Lm of droplet became greater with the increase of ejected pressure for the nozzle that Dn=2, 3mm, but Lm became less for Dn=1mm. Also, when Dn were 2 and 3mm, Lm/Dn was expressed by the function of Re Number and when Dn was 1mm, it was expressed as the function of Re Number and ζn.
4. The trajectory of a droplet which arrived at Lm point was simulated very well under the usage of ua measured by the experiment. It became clear by another simulation that the coverage property was not hardly influenced by the rotation of the high pressure type sprinkler.View full abstractDownload PDF (1316K) -
Effect of digging blade in Baker's garlic-planted sand fieldMasami IWASAKI, Akira ISHIHARA1979 Volume 41 Issue 2 Pages 251-256
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSAs the fundamental studies of lifting type digger development, the draft force, sand surface and Baker's garlic stalks displacement in the planted sand field in the harvest season were measured by the portable draft apparatus with digging blade.
The followings were obtained.
1. When the digging blade passed through the root zone area, the specific resistance (k) was considerably influenced by the cutting resistance of root zone. Also, the cutting of root zone by digging blade was influenced by field moisture content.
2. The cutting efficiency of root zone (Q), which did not show a significant difference among the different shapes, thicknesses and cutting angles of digging blade, was increased with drawing near the bottom of the bulbs and increased with the field moisture content and had a tendency to increase more by using the side blade (S2) than the case of using (S1).
3. The root zone was distributed almost uniformly in the horizontal direction, and 80 to 90% of root zone weight concentrated on the vertical direction at the range of each 5cm to upper and lower side from the bulb bottom.View full abstractDownload PDF (5738K) -
Some Experimental Results obtained from the Test of DetectorKenji NAKAGAWA, Kazuo HORIBE, Hideto KOSAKA, Kazuyuki KONDO, Ikuo MURA ...1979 Volume 41 Issue 2 Pages 257-261
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESS1. It is mainly dependent on the detector whether the accuracy of new shoot plucking operation can be satisfactorily improved or not, in case that the cutter bar position of the tea-plucking machine is controlled automatically. And some operation tests were done in the tea field in order to find proper design specifications of the detector.
2. It is desirable that the sensing plate should be pressed down to the optimum plucking surface or thereabout and slide on the plant surface under the applied pressure when using the sensing plate for detecting the optimum plucking surface. The optimum plucking surface can be stably detected without being affected by unevenness of new shoots under these conditions. The pressure required for keeping proper position of the sensing plate changed widely in places of plant surface, however it may be shown about 1.5-2.0g/cm2.
3. The bigger size sensing plate showed the more stable operation, in the range of plate sizes used in this experiment. However, the distance between the sensing plate and the cutter bar will possibly become too great for the bigger size plate so that such a bigger plate should be avoided.
4. The place shape should be of keeping stable contact area with plant surface regardless of vertical movement. Therefore, a straight sectional shape of the plate is better than an arc shape.
5. The force required to pull the sensing plate being in contact with plant surface is theoretically minimized when the angle of pulling is equal to the one of friction, and thus it is recommended to pull around at that angle of friction. That is about 43-degree angle.View full abstractDownload PDF (780K) -
In Case of a Single GrainKeisuke SUYAMA, Hiroshi SHIMIZU1979 Volume 41 Issue 2 Pages 263-269
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSIn order to investigate the aerodynamical properties of grains, the drag force of the grain in air flow and the rising time of a single grain in a vertical pipe were measured. The following grains were investigated: rough rice, wheat, oats and soybean. The results obtained were as follows;
1. In the range of the air velocity from 15 to 45m/s, the drag force of each grain was almost dependent on the pressure drag force. The variations among the drag coefficients of each grain due to the difference of Reynold's number were small as shown in Fig. 2. The drag coefficients of each grain indicated the maximum value in the direction of its Z axis and the minimum value in its X axis except the soybean. The drag coefficient and the terminal velocity in its three axes directions were given in Table 2 when the air velocity was 15m/s.
2. The flying orientation and the rising velocity of an irregular shaped-particle like the grain in a vertical air pipe were not steady and its rising time before reaching the setting height varied in stochastically as shown in Fig. 4. In case of low air velocity, the variation of its rising time was especially large.
3. A mean actual terminal velocity Vta was defined as the value which subtracted the mean rising velocity before reaching the setting height from the mean air velocity va in the vertical pipe. The relation of the mean actual terminal velocity Vta and the mean air velocity va was shown in Fig. 5.
4. A flying orientation coefficient was defined by the equation (1) from the mean actual terminal velocity Vta, the maximum terminal velocity Vtx and the minimum terminal velocity Vtz.
Vta=n(Vtx-Vtz)+Vtz (1)
The equation (2) was obtained by this experimental results.
n=0.117va-0.574 (2)
In this experimental condition, n was 0.1 to 0.5. It was observed that a rough rice was rised with the posture that its Z axis to be nearly parallel to the direction of the air steam for the low air velocity of about 6m/s. It took its intermediate direction between X and Z axes to be parallel to the air stream for the high air velocity of about 9m/s.
5. If the drag coefficients of the grain for the given three axes are determined, it becomes possible to estimate its mean actual terminal velocity and its rising time at the certain air velocity in the vertical pipe, using this flying orientation coefficient n for the other grains of which their shapes are similar to rough rice.View full abstractDownload PDF (1161K) -
Tetsugi TERUI, Toshinori KIMURA, Yoshio NISITYAMA1979 Volume 41 Issue 2 Pages 271-277
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSEquilibrium moisture content is important for analysis and simulation of drying process. But there have been very few reports concerned with the exact determination of dynamic equilibrium moisture content (DEMC) during drying and its relationship to static equilibrium moisture content (SEMC).
The authors made experiments on drying of wheat grains under various conditions and investigated about the determination of DEMC.
The results obtained are as follows;
1. DEMC should be determined by citing many data from the drying curves. In this sense non linear method of least squares proved to be most desirable.
2. Calculated values of DEMC varied according to the drying times which needed more than 10 to 36 hours for convergence of the DEMC values. The minimum times required for the convergences were ranged from 5.2 to 5.8 in dimensionless time of the sphere modle.
3. Compared with the conventional static method, this dynamic method had an availability to get reproductive DEMC values for wider range of temperatures and humidities.
4. Since the DEMC relationship to air conditions was similar to SEMC relationship reported by Henderson et al., it was considered that two equilibrium moisutre contents were almost the same physical properties.
5. Drying constant K which was calculated from the DEMC was influenced by the conditions of intial moisture content, drying air, variety and drying career.
Consideration of DEMC obtained from this method will contribute to increasing the accuracy of a drying analysis.View full abstractDownload PDF (1085K) -
DLE Fundamental Characteristics of Persimmon FruitsYutaka CHUMA, Kei NAKAJI1979 Volume 41 Issue 2 Pages 279-285
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe delayed light emission (DLE) characteristics of chlorophyll of persimmons (Fuyu fruits) were investigated for the purpose of providing data for the automation of sorting process. The following results were obtained:
1. The DLE intensity of persimmons had a property of dark recovery which changed due to the exiting light intensity (Fig. 2).
2. The effects of fundamental factors such as exciting period, exciting light intensity and fruit temperature upon the DLE intensity were investigated (Fig. 3, 4, 5). From the results obtained, the exciting conditions for obtaining the maxmum DLE intensity were as follows:
Dark period for dark recovery; above 15min
Exciting illuminance; above 2800lx
Exciting period; 1 to 3 sec
Fruit temperature; 22 to 32°C
3. Delayed light of persimmon fruit was emitted from the chlorophyll in the peel tissue. The flesh was considered to aid the chlorophyll in the peel to be excited by the diffuse reflection within the part of the flesh (Fig. 6, 7).
4. The bloom covering the fruit surface, which could cause peel color to be misclassified, had little effect on the DLE intensity of persimmon (Table 2).
5. The DLE intensity of persimmon had a linear relation with the chlorophyll content. A specially high correlation was observed with the content of chlorophyll a and total chlorophyll (Fig. 8, 9, 10).View full abstractDownload PDF (980K) -
Experimental Equations on Compressible Filter CakeHiroshi SHIMIZU, Junichi TAKEDA1979 Volume 41 Issue 2 Pages 287-292
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSTreatment of animal waste is important for labor saving and pollusion control. Since the waste treatment essentially consists of solid-liquid separation, this study aimed at the analysis of filtration characteristics of swine waste which is one of the most important problems today. Experiments and analyses were made through the following procedures;
1. Experiments for constant pressure filtration were carried on by Leef-Test method shown in Fig. 1-1, measuring the filtrated volume (V) as to the time, elimination rate (S) and dried weight of filter cake (Wcn).
2. Eq. (1-10) was derived from the fundamental equation (1-3) of Ruth based upon the assumption of a compressible cake.
3. From the seperate experiments, the second term of eq. (1-10) due to the resistance of a filter and a tube, was considered to be a known term expressed by as eq. (1-15).
4. The result of the experiments by use of the method (1) had a tendency shown in Fig. 1-2. From the experimental results, the authors determined experimental equation (1-18) in which coefficients V, K, J were caluculated by the least square method. The filtration process of compressible filter cake is thus realized by the coefficients k and j of eq. (1-17) which has the same form as the theoretical equation (1-10).View full abstractDownload PDF (919K) -
Takashi TAKEZONO, Kensuke AMANO1979 Volume 41 Issue 2 Pages 293-299
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe paper dealt with a solar greenhouse constructed at Hokkaido national expriment station located at 43°N, Japan. The greenhouse was designed and constructed at reasonable cost in such a way that it could be heated all through the winter without any “artificial” energy supply except the main source of solar energy.
The heat requirement could be reduced with energy conservation arrangements, such as double glazing air inflated house-covering, air inflated plastic film duct (i. e., collector) on the ceiling of the house and multiple movable inside film covering.
The dimensions of the greenhouse are 10.8m of length, 10.8m of width, and 3.5m of height. The solar heating system consists of a tall sidewall of the house, a 772m double tube collector (a transparent outer tube with an inner acceptor tube) of polyethlene (or vinyl) film, and a 29m3 rock pile stsrage unit (insulated with 10cm of polystrene insulator) under the ground inside the house. The system worked well at the effective use of the beam radiation, diffuse radiation and solar radiation reflected from the ground, and re-use of lost heat from the house and from the storage.
In 1977 to 78 winter, the operation of the solar system were conducted. The system worked well to keep the vegetation area over 0°C, to prevent from freezing, even at the outdoor temperature of -26°C. A leafy vegetable variaty, “TAINA” grew well without any supplementary seat source auring in the cold winter.
In this system, solar energy was collected actively through the collector, and passively through the house and soil surface. In the coldest month, Feburary, the total useful heat gain was nearly in in the level of the heat leak from the house at night. The overall collector efficiency was around 30% in winter.View full abstractDownload PDF (2894K) -
1979 Volume 41 Issue 2 Pages 300-300,323
Published: 1979
Released on J-STAGE: April 30, 2010
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[in Japanese], [in Japanese]1979 Volume 41 Issue 2 Pages 301-304
Published: 1979
Released on J-STAGE: April 30, 2010
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[in Japanese], [in Japanese], [in Japanese], [in Japanese]1979 Volume 41 Issue 2 Pages 305-308
Published: 1979
Released on J-STAGE: April 30, 2010
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[in Japanese], [in Japanese]1979 Volume 41 Issue 2 Pages 309-312
Published: 1979
Released on J-STAGE: April 30, 2010
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[in Japanese]1979 Volume 41 Issue 2 Pages 313-321
Published: 1979
Released on J-STAGE: April 30, 2010
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1979 Volume 41 Issue 2 Pages 337a
Published: 1979
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (87K) -
1979 Volume 41 Issue 2 Pages 337b
Published: 1979
Released on J-STAGE: April 30, 2010
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