Authors: Ling Ling, Jun Hao Li, Jiao Li
Abstract: The working principle of lock ring synchronizer was expounded and the synchronous working process of automatic mechanical transmission (AMT) at each stage was analyzed in this paper. Based on the control principle of discrete PID, the corresponding control strategy to three stages was proposed. Then, the degree of jerk when starting of motor vehicle was used as an evaluation criterion. Finally, the bench tests were carried out to verify the feasibility of the proposed control strategy. The experimental results indicate that the control strategy can ensure the demand of jerk, meet the limited synchronous time, improve the smoothness and comfort of gear shift, reduce the wear of the synchronizing ring and increase the lifetime of synchronizer.
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Abstract: A new finishing method of holes that uses an effective electrode and a nonconductive roller to execute the design of synchronous processes of ultrasonic electrochemical finishing and rolling-leveling is investigated. The submitted processes can be used among the traditional techniques of various holes machining. Through simple equipment attachment, ultrasonic electrochemical finishing and rolling-leveling can follow to execute the finishing process on the same machine. Among the factors affecting finishing processes, the performance of rolling-leveling combined with ultrasonic electrochemical finishing is primarily discussed. In the experiment, the electrode is used with continuous and pulsed direct current. The controlled factors include roller material, roller geometry, chemical composition and concentration of the electrolyte, and flow rate of electrolytes. The experimental parameters are frequency and power level of ultrasonics, feed rate of electrode and roller, rotational speed of the finish-tool, die material, electrical current rating, and pulsed period. The design of the synchronous processes through rolling-leveling is the most influential parameter in this study. An adequate finish-tool rotational speed produces better finishing. The average effect of the ultrasonic is better than the pulsed current while the machining time needs not to be prolonged by the off-time. An effective and low-cost finishing process through the ultrasonic electrochemical finishing and using the rolling-leveling assistance after the process of traditional holes machining make the surface of the holes smooth and bright is presented.
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Abstract: The current study using ultrasonic energy transmitted into the electrolyte to assist in
discharging of electrolytic product and cuttings out of the machining gap in the synchronous finish
processes of grinding and electrochemical finishing on hole-wall surface beyond traditional process
of holes machining instead of conventional hand or machine polishing. The design finish-tool
includes a grinding-tool and an electrode as a hole-wall surface finish improvement that goes beyond
traditional rough boring. In the experiment, the finish-tool is completely inserted to the hole; the
electrode is used with continuous or pulsed direct current. The electrode form and the machining
process are obviously different from electrochemical grinding (ECG). The experimental results show
that the large supply of current density is effectively to reach the amount of the material removal and
is advantageous to the finish processes. The finish effect is better with a high rotational speed of the
finish-tool because the dregs and cuttings discharge of electrochemical finishing and grinding
becomes easier and is also advantageous to the finish. The average effect of the ultrasonics is more
better than the pulsed current while the machining time needs not to be prolonged by the off-time. The
synchronous processes of grinding and ultrasonic electrochemical finishing just require a short time to
make the hole-wall surface smooth and bright.
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Abstract: A most effective design system and an advantage of low cost equipment using
synchronous processes of electrochemical finishing and burnishing for a freeform surface following
turning machining is investigated. The proposed design process uses a feeding finish-tool instead of
the mate electrode as in conventional ECM. Hence higher electrical current is not required when the
effective design electrode is used to reduce the response area. Through simple equipment
attachment, electrochemical finishing can follow the traditional turning on the same machine. The
controlled factors include the chemical composition and concentration of the electrolyte, die
material, and rotational speed of workpiece. The design finish-tool is primarily discussed among the
factors affecting the synchronous processes of electrochemical finishing and burnishing. The
experimental parameters are initial gap width, flow rate of electrolyte, current rating, feed rate of
finish tool, pulsed period, and the evaluation of different process features. The use of large
electrolytic flow rate is advantageous to the finish effect. High rotational speed of the finish tool
produces better finish. The finish effect is better with longer off-time because discharge of finish
dregs becomes easier. Higher current rating with quicker feed rate of finish tool effectively reaches
the fast improvement of the surface roughness of the workpiece is recommend in current study. The
effective design finish-tool with an electrode of a globe-form and a burnishing tool of a pin-form
have an optimal value for higher current density and provides larger discharge space, which
produces a smoother surface. The synchronous processes of electrochemical finishing and
burnishing just needs only a short time to make the workpiece smooth and bright and saves the need
for the precise process of traditional machining is recommended for the finish process of the
freeform surface.
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Abstract: In order to elevate the efficiency of the surface finish to reach the fast improvement of the
surface roughness of the workpiece, so as to reduce the residual stress on the surface efficiently. The
present study discusses the surface after traditional machining, of which the plane surface used a
design of finish tool includes an electrode and a nonconductive grinding wheel to execute the
synchronous process of grinding and electrochemical finishing. The electrode form and the
machining process are obviously different from electrochemical grinding (ECG). In the experiment,
the design electrode is used with continuous and pulsed direct current. The controlled factors
include die material, and chemical composition and concentration of the electrolyte. The
experimental parameters are flow rate of electrolytes, position of plate electrode, electrode
thickness, electrode rotational speed, electrical current rating, feed rate of workpiece, and pulsed
period. The experimental results show that the supply of current rating is near concern with the
position and thickness of the plate electrode. The use of large electrolytic flow rate and thick
electrode is advantageous to the finish effect. High rotational speed of finish tool produces better
polishing. The finishing effect is better with longer off-time because discharge of polishing dregs
becomes easier. Higher current rating with quicker workpiece feed rate effectively reaches the fast
improvement of the surface roughness of the workpiece is recommend in current study.
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