Figure 3 The principle chart of selectivity laser sintering

The SLS technique shape speed is fast(general ware, need one or two days to complete), the shape accuracy is high(the minimum thickness of each layer powder is about 0.07 mms, the laser dynamic state accuracy can reach the ±0.09 mms, and have the automatic laser repair function), the prototype strength is high(gather its bent strength of the carbonic acid fat and can amount to the 34.5MPa,the nylon can reach 55MPa), therefore, can carry on function’s experiment and assemble the emulation with the prototype, to obtain the best curved face to match with the observation the condition. Continue reading

hot and fictile shape methods

The hot and fictile shape method burns the knot with the selectivity laser of the DTM company development namely the SLS (the Selective Laser Sintering) application is the most. That method is a way manufacture kind piece that burns with the CO2 laser machine controls by the calculator, carry on scanning on the material powder according to several information for faces of several pieces with horizontal each layer of the body, the powder is scanning by laser and solidify together. Then, spread up a new powder of layer, then scan to burn the knot with the laser, thus again and again, keep to go to make the kind piece which needed. As figure 3 shows.

Solidification resin materials using laser light shapes law

The light shape equipment is excellent with a product of the 3D Systems company of the United States, and the formation of a monopoly. Figure 1 shows the operating principles. Issued by the laser light, the optical system to compile into a small beam, the beam in the computer controlled, selective scanning resin surface, using an ultraviolet resin Frozen mechanisms, a layer of solidification resin, each layer of solidification, precision workstations in a distance with the new layer of surface geometric information to the laser scanner for scanning reading, solidification of the new layer of resin and firmly stick to the previous layer has solidification resin, so repeatedly until the production of spare parts entities generated a model. The laser stereoscopic shape manufacturing accuracy can reach the ±0.1 mms, mainly used to provide the sample and the experiment models for the product. In addition, the SOLIFORM of the Japanese system machine developed can manufacture to inject to model the molding tool and vacuum molding tools directly.

Rapid prototyping technology concept that the concept RP

Rapid prototyping technology concept that the concept RP (Rapid Prototyping Technology) could be back to 1979. the profess of Zhong Chuan Weixiong in produce and technique institute of Japanese University of Tokyo invent the method of fold the layer model, the Xiao Yu Xiunan put forward the light shape method again in 1980, after the conceive put forward, it was continued to study in 1984 by Wan Gu Yanger, and carried on to produce manufacture on a trial basis in 1987.

1988, the United States rapidly prototype 3D Systems Corporation was the first to introduce practical devices-laser three-dimensional shapes that SLA (Stereo Lightgraphy Apparatus), and annual sales growth rate 30%~40% increase in the world market. In recent years, with increasing performance scanning-a mirror, and the development of materials science and computer technology, rapid prototyping technology matures, and in 1994 to promote universal access to the formal stage. In accordance with the patterns and materials used in the different types of rapid prototyping technology currently has the following four types.

The characteristics of Rapid Prototyping Technology

Rapid Prototyping Technology breaks the traditional way to produce spare parts of “roughcast àslice to pare to processàfinished”, Needless cutlery created the first production of spare parts, is an unprecedented lamina reducing processing methods. Comparing to tradition, the fast prototype processes the following advantage:

(1)Produce the spare parts of the curved face and more complicated appearance quickly, such as shoulder within spare parts and hollow and parts of etc.s, consumedly lowered the development cost of the new product and development period. Continue reading

The basic principle of Rapid Prototyping Technology

The RP is the generic name of the principle creation product prototype that uses the long-lost layering, its principle is: Produce CAD modelà Stratified separated àaccording to the plan geometry information which is dispersed to pile up the original materialà generating entity models.

This technology integrates of computer technology, laser processing technology, new material technology, relying on CAD software in the creation of 3D computer models entities, and is divided into a series of plane geometry information to control the scanning laser beam direction and speed, using sinter, pooling or chemical reaction means exhaustive selective processing of raw materials, thus rapid accumulation manufacture products entities models.

The selection of design principles connectors

Connectors and electrical components selected to ensure good contact, the contact resistance reduced to a minimum, improve reliability, preferred structure of the double spring clamp connectors.

According to the wire cross-sectional area and a reasonable choice by the current size of the connectors.

Sheath docking engine compartment, as the cabin temperature and humidity is too large and there are a lot of corrosive gases and liquids, so be sure to choose waterproof jacket. Continue reading

Ground distribution design principles

Engine ECU, ABS and other vehicle performance and safety of impact, and other electrical equipment susceptible to interference, so these pieces of Ground point must be a single set.

For airbag system, it should not only be a single set point Ground, and in order to ensure their safe and reliable, preferably double-Ground. The aim is one of a Ground failure, the system can point to another Ground Ground, to ensure system security. Continue reading

The selection of the relay design

Relay is divided into current-and voltage-type two kinds. Generally based on the use of electrical power and switch to determine whether the carrying capacity of selected relays. Relay devices are generally used wipers, horn, defroster, headlights, fog lights, fans, blowers, turn lights (flasher) and so on. Relay sub-6V, 12V, 24V3 species, common relays rated at 12V.

Use the relay to refer to the technical requirements: ① reliability; ② stable performance; ③ light weight, small size, long life, little impact on the surrounding components; ④ simple structure, good process, and low cost.

Automotive wiring harness design and material selection

Auto wiring harness car circuit network is the main wiring harness can not exist without the car circuit. With the car’s safety, comfort, economy and emissions requirements increase, automotive wiring harness becomes more complex, but the body harness to give the space is getting smaller and smaller. Therefore, how to improve the overall performance of automotive wiring harness design has become the focus of attention, and automotive wiring harness manufacturer, wiring harness is no longer simply engaged in the latter part of the design and manufacturing, and automotive manufacturers to co-host for pre-development has become an inevitable trend. Based on the author in the years of experience designing and manufacturing wiring harness, wiring harness to talk about the general design process and design principles. Continue reading