Effective Stripper-Holding on High Speed Precision Blanking of Electronic Machine Parts

2005 ◽  
Vol 6-8 ◽  
pp. 805-808
Author(s):  
F. Sekine
Keyword(s):  
Mechanical Model ◽  
High Speed ◽  
Thin Sheet ◽  
Dimensional Accuracy ◽  
New Method ◽  
Important Process ◽  
Sheet Metals ◽  
Progressive Dies ◽  
Machine Parts

The blanking of thin sheet metals using progressive dies is an important process on production of precision electronic machine parts. As a model of IC leadframe, an I-shaped and an Lshaped models were blanked and influences of blanking conditions on dimensional accuracy of blanked lead were examined. Furthermore, a mechanical model is proposed to explain the affect of the blanking conditions on product accuracy. In these days, more fine leads are required as electronic machines become more precise and accurate. It must be treated that leads are firmly held for blanking leadframes accurately. In this paper, an effective method of stripper holding leads strongly are discussed and a new method using newly designed stripper is proposed. Consequently the effect of it on lead accuracy is proved.

Development of a New High-Precision Feeder for Micro-Sheet-Forming

2011 ◽  
Vol 133 (6) ◽  
Author(s):  
Akhtar Razali ◽  
Yi Qin ◽  
Jie Zhao ◽  
Colin Harrison ◽  
R. Smith
Keyword(s):  
High Precision ◽  
High Speed ◽  
Feeding Rate ◽  
Thin Sheet ◽  
Raw Material ◽  
Sheet Metals ◽  
Promising Solution ◽  
Feeder Design ◽  
Progressive Forming ◽  
Accuracy And Repeatability

Feeding the raw material accurately is essential in microsheet-forming, especially in multistage progressive forming operations and also when in particular, a certain feeding rate has to be maintained. Research into the microforming of thin sheet metals (<100 μm) led to investigations of the performance of existing sheet metal feeders, regarding their feeding accuracy and repeatability. The results indicated that the pursuance of greater feeding accuracy and repeatability, which was aimed at 5–15% of the strip thickness, was difficult to achieve with commercially-available feeders. A new high-precision and high-speed feeder was, therefore, developed for microsheet-forming. The feeder design was supported by motion analysis and feeding simulations. The feeder was constructed in collaboration with industrial partners. The conducted feeding tests and forming experiments demonstrated that greater feeding accuracy and repeatability can be achieved, compared to those of existing commercial feeders. This suggests a promising solution for high-precision strip feeding in microsheet-forming where thin sheet metals are to be fed.

A new method used for high speed pseudo-random code generating

2014 ◽  
Author(s):  
Zhanfeng Zhao ◽  
Dong Zhang ◽  
Zhiquan Zhou
Keyword(s):  
High Speed ◽  
New Method ◽  
Random Code

scholarly journals A New Method to Verify the Measurement Speed and Accuracy of Frequency Modulated Interferometers

2021 ◽  
Vol 11 (13) ◽  
pp. 5787
Author(s):  
Toan-Thang Vu ◽  
Thanh-Tung Vu ◽  
Van-Doanh Tran ◽  
Thanh-Dong Nguyen ◽  
Ngoc-Tam Bui
Keyword(s):  
Phase Change ◽  
High Speed ◽  
Measurement Accuracy ◽  
Slow Motion ◽  
New Method ◽  
Virtual Displacement ◽  
Electro Optic ◽  
Lock In ◽  
Speed And Accuracy ◽  
Electro Optic Modulator

The measurement speed and measurement accuracy of a displacement measuring interferometer are key parameters. To verify these parameters, a fast and high-accuracy motion is required. However, the displacement induced by a mechanical actuator generates disadvantageous features, such as slow motion, hysteresis, distortion, and vibration. This paper proposes a new method for a nonmechanical high-speed motion using an electro-optic modulator (EOM). The method is based on the principle that all displacement measuring interferometers measure the phase change to calculate the displacement. This means that the EOM can be used to accurately generate phase change rather than a mechanical actuator. The proposed method is then validated by placing the EOM into an arm of a frequency modulation interferometer. By using two lock-in amplifiers, the phase change in an EOM and, hence, the corresponding virtual displacement could be measured by the interferometer. The measurement showed that the system could achieve a displacement at 20 kHz, a speed of 6.08 mm/s, and a displacement noise level < 100 pm//√Hz above 2 kHz. The proposed virtual displacement can be applied to determine both the measurement speed and accuracy of displacement measuring interferometers, such as homodyne interferometers, heterodyne interferometers, and frequency modulated interferometers.

Characteristics of Rotary Draw-Bent Tubes for the Hydroforming

2011 ◽  
Vol 213 ◽  
pp. 320-324
Author(s):  
Byeong Don Joo ◽  
Jeong Hwan Jang ◽  
Hyun Jong Lee ◽  
Young Hoon Moon
Keyword(s):  
Cross Section ◽  
Structural Strength ◽  
Dimensional Accuracy ◽  
Thickness Variation ◽  
Important Process ◽  
Rotary Draw Bending ◽  
Higher Dimensional ◽  
Bending Process ◽  
Geometric Size ◽  
Draw Bending

Hydroformed parts have higher dimensional accuracy, structural strength, and dimensional repeatability. The pre-bending process is an important process for the successful hydroforming in the case where the perimeter of the blank is nearly the same as that of final product. At initial pre-bending stage, the variations of wall thickness and cross-section have effects on the accuracy of final products and quality. Because of a relatively excellent productive velocity, geometric size precision and reliance of product qualities, rotary draw bending is widely used. This study shows the bendability such as cross-section ovality, springback ratio and thickness variation in the various conditions of materials.

Morphology of Edge Cracks of Rolled Magnesium Alloy Sheet

2014 ◽  
Vol 922 ◽  
pp. 469-474 ◽  
Author(s):  
Sho Manabe ◽  
Hiroshi Utsunomiya ◽  
Tetsuo Sakai ◽  
Ryo Matsumoto
Keyword(s):  
Magnesium Alloy ◽  
Magnesium Alloys ◽  
High Speed ◽  
Heating Temperature ◽  
Thin Sheet ◽  
Contact Length ◽  
Alloy Sheet ◽  
Different Temperatures ◽  
Edge Cracks ◽  
Critical Reduction

Magnesium alloys show low deformability at low temperature because of hcp structure and inactiveness of basal slip. Manufacturing of thin sheet is difficult in industries. Some approaches, such as small-draft multi-pass rolling, intermediate annealing, isothermal rolling and high-speed rolling were proposed to overcome the deformability. However, small edge cracks are still formed on the sheet. In this study, rolling speed of 1000m/min was employed to warm-roll AZ31B magnesium alloy in a single pass at different temperatures. The edge cracks formed after the rolling were classified into three main groups: minor, regular and zigzag edge cracks. ‘Crack contact length’ are introduced to explain the morphology of edge cracks. The results show that the critical reduction for crack initiation depends on the pre-heating temperature. The spacing between edge cracks increases linearly with the crack contact length regardless of roll diameter, speed and reduction. It is suggested that this approach is useful to understand the formation mechanism of edge cracks and to evaluate the rollability of magnesium alloys.

Measurement of Dynamic Strain

1943 ◽  
Vol 10 (2) ◽  
pp. A85-A92
Author(s):  
C. O. Dohrenwend ◽  
W. R. Mehaffey
Keyword(s):  
High Speed ◽  
Shock Loading ◽  
Low Frequency ◽  
Dynamic Strain ◽  
Time Axis ◽  
Low Frequencies ◽  
Strain Measurements ◽  
Moving Vehicles ◽  
Machine Parts ◽  
Dynamic Strains

Abstract The measurement of dynamic strains of both high and low frequency give rise to a variety of problems in instrumentation. Two types of equipment and circuits designed and used by the authors are discussed in detail. The first type based on the amplitude-modulated method is for low frequencies from zero to about 15 per cent of the carrier frequency of 1025 cycles per sec. The equipment has application to strain measurements varying from static values to those produced in moving vehicles, various machine parts, structures such as crane bridges, in fact all strain measurements where the frequency is 150 cycles per sec or less. The second type of equipment discussed is a potentiometer type and is for high-frequency strain measurements from 100 cycles per sec to 8000 cycles per sec. This high-speed equipment is conveniently used for impact strain, such as produced in hammer blows, shock loading, forging equipment, and impact-factor determination. Both units are designed to be used with a cathode-ray oscillograph which lends itself to a variety of recording methods. The methods discussed include both the type where the time axis is obtained by sweeping the oscilloscope beam on a stationary film and where the time axis is obtained mechanically.

Characterization of Tensile and Compressive Behavior of Microscale Sheet Metals Using a Transparent Micro-Wedge Device

2011 ◽  
Author(s):  
James Magargee ◽  
Jian Cao ◽  
Rui Zhou ◽  
Morgan McHugh ◽  
Damon Brink ◽  
...  
Keyword(s):  
Mechanical Behavior ◽  
Thin Sheet ◽  
Thin Sheets ◽  
Stainless Steel Sheet ◽  
Sheet Metals ◽  
Compressive Behavior ◽  
Buckling Modes ◽  
Full Field ◽  
Compressive Loads

The cyclic and compressive mechanical behavior of ultra-thin sheet metals was experimentally investigated. A novel transparent wedge device was designed and fabricated to prevent the buckling of thin sheets under compressive loads, while also allowing full field strain measurements of the specimen using digital imaging methods. Thin brass and stainless steel sheet metal specimens were tested using the micro-wedge device. Experimental results show that the device can be used to delay the onset of early buckling modes of a thin sheet under compression, which is critical in examining the compressive and cyclic mechanical behavior of sheet metals.

scholarly journals MAGNETIC FORCES AND CURRENTS OF THE INDUCTOR FOR MAGNETIC-PULSE PROCESSING OF OF WELDING JOINTS OF NON-MAGNETIC THIN SHEET METALS

2020 ◽  
Vol 2020 (5) ◽  
pp. 74-79
Author(s):  
A.P. Raschepkin ◽  
◽  
I.P. Kondratenko ◽  
O.N. Karlov ◽  
R.S. Kryshchuk ◽  
...  
Keyword(s):  
Thin Sheet ◽  
Magnetic Pulse ◽  
Sheet Metals ◽  
Magnetic Forces ◽  
Pulse Processing ◽  
Welding Joints
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