the effective factors of forward speed, cylinder rotation, and clearance between a combine’s cylinder and concave on wheat kernel breakage and seed germination were studied in karaj area using a 955 model john dear combine. this study was conducted on three levels of adjustment for each of the variables, 1.2, 1.8 and 2.5 km/hr for forward speed, 800, 900, 1000 rpm for cylinder rotation as well ...

In this paper, we developed a detailed mathematical model of dual action pneumatic actuators controlled with proportional spool valves. Effects of nonlinear flow through the valve, air compressibility in cylinder chambers, leakage between chambers, end of stroke inactive volume, and time delay and attenuation in the pneumatic lines were carefully considered. System identification, numerical sim...

This paper proposes a control approach that can provide significant energy savings for the control of pneumatic servo systems. The control methodology is formulated by decoupling the standard four-way spool valve used for pneumatic servo control into two threeway valves, then using the resulting two control degrees of freedom to simultaneously satisfy a performance constraint (which for this pa...

A problem with pneumatic positioning systems is the low energetic efficiency. This paper presents a structure of a compressed air saving for pneumatic positioning systems with capacity to move high loads. This structure use the loading to save compressed air and thus to increase the energetic efficiency of these systems. This configuration adds a fast switching on/off valve in a feedback betwee...

Prediction of pressure pulsation magnitude and their harmonic components for a multistage reciprocating compressor, piping and reservoir system depends on the input design and operating parameters. In the present paper, the results of the theoretical study carried out to study the effect of such parameters on pressure pulsations and their harmonics have been presented. The effect of pipe diamet...

This paper investigates the problems of cylinder fitting in laser scanning three-dimensional Point Cloud Data (PCD). Most existing methods require full cylinder data, do not study the presence of outliers, and are not statistically robust. But especially mobile laser scanning often has incomplete data, as street poles for example are only scanned from the road. Moreover, existence of outliers i...

A new energy-saving mechanical system with automatically controlled air valves has been proposed by investigator and the preliminary model setup has been tested. The testing results indicated the proper function of this energy-saving mechanical system. This mechanical system model has been simulated and analyzed by the computational aided engineering solution. The major advantages of this mecha...

Given the need to reduce greenhouse gas emissions, new energy-efficient solutions can be adopted for construction and agricultural machinery. Such a solution is digital hydraulic cylinder that uses several active areas constant pressure supply with which gradual variation of driving force obtained. Traditional systems have high energy losses due direct throttle flow through different valves. Th...

To bridge the gap that exists in key equipment of new subsea production control system, all-electric gate valve actuator, and exploit oil gas resources with high reliability safety while saving energy, this paper proposes a novel concept prototype an actuator which has functions redundant drive, failsafe closing, auxiliary override, position indication, low-power holding. It satisfied electrica...

(g) pumps incorporating measuring devices, of heading 8413; weight–operated counting and checking machinery, or separately presented weights for balances (heading 8423); lifting or handling machinery (headings 8425 to 8428); paper or paperboard cutting machines of all kinds (heading 8441); fittings for adjusting work or tools on machine tools, of heading 8466, including fittings with optical de...