Research and analysis on the surface accuracy of lapping plat in single-sided lapping machine with reciprocating motion of conditioning ring

The experimental investigation of reciprocating motion between the aluminum doped crumb rubber /epoxy composite and the steel ball has been carried out under Reciprocating Friction Tester, TR-282 to study the wear and coefficient of frictions using different normal loads (0.4Kg, 0.7Kgand1Kg), differentfrequencies (10Hz, 25Hz and 40Hz).The wear is a function of normal load, reciprocating frequency, reciprocating duration and the composition of the material. The percentage of aluminum presents in the composite changesbut the other components remain the same.The four types of composites are fabricated by compression molding process having 0%, 10%, 20% and 30% Al. The effect of different parameters such as normal load, reciprocating frequency and percentage of aluminum has been studied. It is observed that the wear and coefficient of friction is influenced by the parameters. The tendency of wear goes on decreasing with the increase of normal load and it is minimum for a composite having 10%aluminum at a normal load of 0.7Kg and then goes on increasing at higher loads for all types of composite due to the adhesive nature of the composite. The coefficient of friction goes on decreasing with increasing normal loads due to the formation of thin film as an effect of heat generation with normal load.

Download Full-text

ON THE HYBRID-DRIVEN LINKAGE MECHANISM WITH ONE INPUT CYCLE CORRESPONDING TO TWO OUTPUT CYCLES

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2015-0050 ◽

2015 ◽

Vol 39 (3) ◽

pp. 637-646

Author(s):

Ren-Chung Soong

Keyword(s):

Kinematic Analysis ◽

Angular Speed ◽

Motion Trajectory ◽

Dimensional Synthesis ◽

Reciprocating Motion ◽

Linkage Mechanism ◽

Output Link ◽

Input And Output ◽

Single Input ◽

Selection Of

A hybrid-driven five-bar linkage mechanism with one input cycle corresponding to two output cycles is presented. The proposed linkage mechanism is driven by a constant-speed motor and a linear motor, respectively. The output link can generate two same required output cycles during a single input cycle, while the rotational input link rotates with a constant angular speed, and the linear input link follows a reciprocating motion along a specified linear guide fixed on the rotational input link. The configuration, displacement relationship between the input and output links, and conditions of mobility of this proposed mechanism were studied, and a kinematic analysis was performed. The selection of the instantaneous motion trajectory of the linear input link and an optimal dimensional synthesis are also described. An example is provided to verify the feasibility and effectiveness of this methodology.

Download Full-text

Apical Extrusion of Debris Produced during Continuous Rotating and Reciprocating Motion

The Scientific World JOURNAL ◽

10.1155/2015/267264 ◽

2015 ◽

Vol 2015 ◽

pp. 1-5 ◽

Cited By ~ 4

Author(s):

Giselle Nevares ◽

Felipe Xavier ◽

Luciana Gominho ◽

Flávia Cavalcanti ◽

Marcely Cassimiro ◽

...

Keyword(s):

Cross Section ◽

Sodium Hypochlorite ◽

Reciprocating Motion ◽

Continuous Motion ◽

Analytical Balance ◽

Root Canals ◽

Apical Extrusion ◽

Final Weight ◽

The Difference

This study aimed to analyse and compare apical extrusion of debris in canals instrumented with systems used in reciprocating and continuous motion. Sixty mandibular premolars were randomly divided into 3 groups (n=20): the Reciproc (REC), WaveOne (WO), and HyFlex CM (HYF) groups. One Eppendorf tube per tooth was weighed in advance on an analytical balance. The root canals were instrumented according to the manufacturer’s instructions, and standardised irrigation with 2.5% sodium hypochlorite was performed to a total volume of 9 mL. After instrumentation, the teeth were removed from the Eppendorf tubes and incubated at 37°C for 15 days to evaporate the liquid. The tubes were weighed again, and the difference between the initial and final weight was calculated to determine the weight of the debris. The data were statistically analysed using the Shapiro-Wilk, Wilcoxon, and Mann-Whitney tests (α=5%). All systems resulted in the apical extrusion of debris. Reciproc produced significantly more debris than WaveOne (p<0.05), and both systems produced a greater apical extrusion of debris than HyFlex CM (p<0.001). Cross section and motion influenced the results, despite tip standardization.

Download Full-text

The Combustion Gas Turbine: Its History, Development, and Prospects

Proceedings of the Institution of Mechanical Engineers ◽

10.1243/pime_proc_1939_141_033_02 ◽

1939 ◽

Vol 141 (1) ◽

pp. 197-222 ◽

Cited By ~ 6

Author(s):

Adolf Meyer

Keyword(s):

Gas Turbine ◽

Power Supply ◽

Chemical Processes ◽

Wind Tunnels ◽

Inlet Temperature ◽

Reciprocating Motion ◽

Combustion Gas ◽

Marine Propulsion ◽

Cracking Process ◽

Principal Advantage

By “combustion gas turbine” is meant a turbine actuated by the steady flow of the products of a continuous combustion under pressure in a combustion chamber. Inventors appear to have been at work on the gas turbine since 1791, the original attractions of the proposal being its simplicity and the elimination of the reciprocating motion of the early steam engines. Simplicity remains the principal advantage of the gas turbine, though the first applications have been made possible by the needs of special chemical processes, such as the Houdry cracking process. The efficiency attainable under present conditions is 17–18 per cent, but this would be increased to 23 per cent if the gas inlet temperature could be raised from 1,000 to 1,300 deg. F. The proposed new fields of application of the gas turbine include locomotive and marine propulsion, blast furnace plants, and the power supply for wind tunnels.

Download Full-text

Analysis of structures of flat planting machines

Journal of Mechanical Engineering and Transport ◽

10.31649/2413-4503-2021-13-1-140-148 ◽

2021 ◽

Vol 13 (1) ◽

pp. 140-148

Author(s):

Andrіі Slabkyі ◽

◽

Olexandr Manzhilevskyy ◽

Olexandr Polishchuk ◽

◽

...

Keyword(s):

Cutting Tool ◽

Relative Movement ◽

Statistical Parameters ◽

Abrasive Finishing ◽

Wide Range ◽

Uneven Wear ◽

Lapping Machine ◽

Numerical Program ◽

Hydraulic Pulse

One of the methods of material processing is considered, which allows to obtain high geometric accuracy and low surface roughness of parts, namely their abrasive finishing. The high quality of machining of parts in this way is due to the use of coordinated relative movement of the workpiece and the cutting tool. According to the kinematic features, most lapping machines can be divided into two groups: machines with oscillating working motion and machines with rotating lapping motion. The machines of the first group are more common due to the simplicity of their design and versatility. However, the possibility of their use is limited by the size range of the workpieces and uneven wear of the cutting tool and, as a consequence, the uneven surface treatment of the part. The machines of the second group are considered the most versatile, as they allow processing a wide range of parts, varying in shape and size, but they are also not without such a disadvantage as uneven wear of the cutting tool with all the corresponding consequences. Improving the efficiency of abrasive finishing by complicating the trajectory of the relative movement of the tool and the part, ie the formation of a unique mutual working movement of the lapping and the movement of the workpiece, is one of the most common areas. The main disadvantage of equipment that provides processing of parts on this principle is, in most cases, limited regulation of the operating parameters of the cutting process, so this area remains promising and has broad prospects for development. The constructive scheme of the hydraulic-pulse flat-lapping machine offered in work thanks to a combination of advantages of the hydraulic-pulse drive with use of numerical program control will allow to provide unique mutual multi-movement of preparation and the lapping tool with a possibility of adjustment of its parameters in the course of processing. Purposeful choice of the shape and density of the trajectory of the working movement of the tool will form a micro relief of the treated surface with the necessary statistical parameters and low roughness.

Download Full-text

Real-time Closed-loop Active Surface Technology of a Large Radio Telescope

Publications of the Astronomical Society of the Pacific ◽

10.1088/1538-3873/ac32af ◽

2022 ◽

Vol 134 (1031) ◽

pp. 015003

Author(s):

Yong Zhang ◽

Guoping Li ◽

Guohua Zhou ◽

Qishuai Lu ◽

Heng Zuo ◽

...

Keyword(s):

Real Time ◽

Radio Telescope ◽

Closed Loop ◽

Preliminary Test ◽

Active Surface ◽

Angle Measurement ◽

Quality Data ◽

Surface Accuracy ◽

Surface System ◽

Reflector Surface

Abstract The surface accuracy of a large radio telescope’s primary reflector is easily affected by gravity and temperature change during observations. An active surface system is crucial to ensure the regular operation and high-quality data output of the radio telescope. We propose a real-time closed-loop active surface system including two components. The first component, a new type of photoelectric edge sensor, detects the angle change of the adjacent panels. The second component, the displacement actuator, adjusts the panels’ position and posture to compensate for the angle changes. So, over the entire observation, the closed-loop surface control system with these two components could actively maintain the primary reflector’s accuracy in real time. Using this approach, we constructed an experimental active surface system for the Xinjiang Qitai 110 m Radio Telescope (QTT) to test the maintenance of the surface accuracy. The angle measurement accuracy is better than 0.″2, and the positioning accuracy of the displacement actuator could achieve ±15 μm over the whole 50 mm stroke. The preliminary test results show that the accuracy requirements of the QTT’s primary reflector surface can be met using the active surface system we propose.

Download Full-text

Engineering of a lapping machine with a cycloidal toolpath

Metalloobrabotka ◽

10.25960/mo.2019.2.54 ◽

2019 ◽

pp. 54-59

Author(s):

Karim Ravilevich Muratov ◽

Evgeny Anatolyevich Gashev ◽

Daria Petrovna Ismailova

Keyword(s):

Lapping Machine

Download Full-text

Experimental study of pin surface precision on lubrication behavior of pin–bush pairs in industrial roller chains

Industrial Lubrication and Tribology ◽

10.1108/ilt-10-2020-0369 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Ansheng Zhang ◽

Mingyu Zhang ◽

Jing Wang ◽

Jianjun Zhang ◽

Zhaohua Shang ◽

...

Keyword(s):

Experimental Study ◽

Design Methodology ◽

Industrial Applications ◽

Experimental Basis ◽

Reciprocating Motion ◽

Content Type ◽

Oil Supply ◽

Machining Errors ◽

Surface Precision ◽

Straightness Error

Purpose The purpose of this paper is to study the influence of surface precision on the lubrication state of the roller chain under adequate and rare oil supply conditions, respectively. Design/methodology/approach The straightness error and roughness error of the pin generatrices were measured and the influence of surface precision on the lubrication behavior under steady state and reciprocating motion was studied through optical interference experiments. Findings The lubrication state is strongly influenced by the surface precision of the roller surface both under adequate oil supply and rare oil supply conditions. Originality/value In industrial applications, the machining errors of parts cannot be completely eliminated. Studying the influence of the surface precision on the lubrication behavior of pin–bush pairs can provide the experimental basis for the optimal design of the bush roller chains.

Download Full-text

Overconstrained Mechanisms with Radially Reciprocating Motion

Advances in Robot Kinematics: Motion in Man and Machine ◽

10.1007/978-90-481-9262-5_31 ◽

2010 ◽

pp. 293-300 ◽

Cited By ~ 3

Author(s):

Guowu Wei ◽

Jian S. Dai

Keyword(s):

Reciprocating Motion ◽

Overconstrained Mechanisms

Download Full-text