塑料注射模-注塑模具模具基本术语毕业课程设计外文文献翻译、中英文翻译

Basic terminology

1、Impression

The injection mould is an assenbly of parts containing within an inpression into which plastic material is injected and cooled. It is the impression which gives the moulding its form. The impression may, therefore, be defined as thatpart of the mould which imparts shape to the moulding.

The impression is formed by two mould mimbers:

(i)The cavity, which is the female portion of the mould, gices the moulding

its external form.

(ii)The core, which is the male portion of the mould , forms the internal shape of the moulding.

2、Cavity an core plates

The basic mould in this case consists of two plates. Into one plate is sunk the cavity which shapes the outside form of the moulding and os therefore known as the cavity plate. Similarly, the core which projects form the core plate forms the inside shape of the moulding os closed, the two plates come together forming a space between the cavity and core which is the impression.

3、Sprue bush

During the injection process plastic material is delivered to the mozzle of the machie as a melt;it is then tramsferred to the impression though a passage. The material in this passage is termed the sprue, and the bush is called a sprue bush.

4、Runner and gate systems

The material may bedirectly injected into the impression though the sprue bush or for moulds containing several impressions it may pass from the sprue bush hole through a runner and gate system therefore entering the impression.

5、Register ring

If the material is to pass without hidrance into the mould the mozzle and sprue must be correctly aligned. To endure that this is so the mould must be central to the machine and this can be achieved by including a regicter ring.

6、Guide pillars and bushes

To mould an even-walled article it is necessary to ensure that the cavity and core are keptin alignmemt. This is done by incorporating guide pillars on one mould plate which then enter corresponding guide bushes in the other mould plate as the mouls

7、Fixed half and moving half

The various mould parts fall naturally into two sections or halves. Hence, that half attached to the stationary platen of the machine (indicated by the chain dotted line)is termed the fixed half, The other half of the mould attached to the moving platen of the machine is known simply as the moving half. Now it has to be situsted. Generally the core is situated in the moving half and the overriding reason why this is so, is as follows:

The moulding as it cools, will shrink on to the core and remain with it as the mould opens. This will occur irrespective of whether the core is in the fixed half or the moving half. However, this shrinkage on to the core means that some form of ejector system is almostly certainly necessary. Motivation for this ejector system iseasily provided if the core is in the moving half. Moreover, in the case of our single-impression basic mould, where a direct sprue feed to the underside of the moulding is desired the cavity must be in the fixed half and the core in the moving half.

8、Methods of incorporating cavity and core

We have now seen that in general the core is incorporsted in the moving half and the cavity in the fixed half. However, there are various methods by which the cavity and core can be incorporated in their respective halves of the mould. These represent two basic alternatives (i) the integer method where the cavity and core can be machined form steel plates which become part of the structural build-up of the mould, or (ii) the cavity and core can be machined form small blocks of steel, termed inderts, and subsequently bolstered. The choice between these alternatives constitutes an important decision on the part of the mould designer. The final result, nevertheless, will be the contains the core is termed the core plate and the plate or assembly which contains the cavity is termed the cavity plate.

9、Cavity Fabrication

When a decision for making a mold is made, the cost is predicated on producing a specified quantity of parts without additional tooling expenditure. Sometimes, the anticipatesare quantities are exceeded; other times, they all short of requirements, and costly repairs becomenecesary in order to supply the needs.

In the making of cavities by machining, grinding, or electric discharge machining, there is constant drive to improve the rate of metal removal. Cutting tools as well as