An Improved Design of the Engine Bench Test Tool for the Dual Mass Flywheel (DMF)

At present, a lot of passenger cars and light trucks are equipped with the dual mass flywheel, which can decrease the non-uniformity of the indicated engine torque. In engine bench test, the secondary mass of the dual mass flywheel can’t be fixed because there is no transmission system on the test bench. As a result, the secondary mass of the dual mass flywheel will have radial and circumferential movements, which may lead to a damage to the dual mass flywheel. This paper presents an improved design of the crafting tool for the dual mass flywheel to protect the secondary mass during the engine bench test. For the improved design, the cylinder body is used for the positioning of the crafting tool, and a spline shaft and a ball bearing of centripetal adjustment are chosen to fix the secondary mass. Through this tool, the dual mass flywheel engine can be tested on the test bench without a starting shaft, and the disassembling of the engine flywheel bolts during the hot test can be avoided.

THEORETICAL RESEARCH STUDIES OF REGULARITIES FORMATION OF ACOUSTIC CHARACTERISTICS FOR THREADING AND SPLINE SHAFT MILLING MACHINE

The research paper presents the theoretical studies results of noise generation during workpieces processing on threading and spline shaft milling machines. It is proposed the analytical dependence determining the sound pressure and sound power for various acoustic models of the noise sources with grounding conditions of the cutting tool, workpieces and their geometric dimensions.

Manufacturing of the surfaces of spline fitting connection

The aim of this publication is the analysis of the geometric establishment and the manufacturing designing and development of spline fitting promoting the engineer’s designing works. There are many connection possibilities according to the utilization on different constructions. Based on them, different technologies are needed for the manufacturing of the spline shaft and the spline hole. Generally, milling and grinding technologies are needed. These technologies will be analysed. We design mathematical models for the analysis of the milling technologies by mathematical way. We define the technological parameters and the computed machine time for the manufacturing designing process and recommend technologies for the different shapes.

Effect of floating axial holder on oscillating cold forging of spline shaft

Oscillating technique is applied into the axial forging process of spline shaft to decrease the forming load and improve the quality of products. A floating axial holder with dwell force is designed to control the material flow. The influences of the floating axial holder have been analysed by finite element (FE) simulation and then verified by experiments. A FE model that considers material property change, elastic recovery and elastoplastic friction was built. The constitutive material model, which is mainly composed of variable elastic modulus and rate-dependent hardening, was used to simulate changes in material properties. Results showed that material flow was improved by decreasing dwell force. Tooth shape can be controlled by changing the dwell force of floating axial holder. The nonlinear function between addendum circle diameter and dwell force has been found. Hence, an optimal value of dwell force was determined considering the forming force, forming defects and tooth shape. Based on the simulating results, the optimal and irrational parameters of dwell force and frequency have been compared in the experiments. The typical defects of flash and accumulation can be eliminated by using the floating axial holder with optimal parameters.