The structure of the mould slider (line position) is easy to understand for demoulding

In plastic injection moulds, the opening action of the mould is used to produce a relative movement trend between the diagonal support tip and the slider, so that the slider is released from the inverted hook in two forms of movement along the opening direction and in the horizontal direction.

The slider has to move a certain distance during the mould opening process, and after the front and rear moulds are completely separated, the slider has to be able to return to its position safely. The slider has to stop in the correct position. If the slider slides further forward or backwards, it will cause the bevelled edge to collide with the hole when the mould is closed! Therefore, the slider must be equipped with a positioning device, which must be flexible and reliable to ensure that the slider does not move in its original position.

1. Screw positioning

The advantage is that it is easy to process and simple to operate; the disadvantage is that it is easily damaged. It is commonly used in the X-direction (horizontal) for small rows and rows with large travel. It can also help to delay the opening of the mould, as the beveled edge does not work when the ball will not move against the line. 2.

2. Spring and limit screw positioning

The advantages are easy processing and safe positioning. Commonly used in x- and y-directional rows and rows with small travel. Calculation of the spring: First of all, we should know that the pre-pressure of the line position spring means that it has a pre-pressure after opening the mould to move away from the buckle position.

(L stroke + 3~5 pre-pressure amount)/40% = L0 (free length)

Spring hole depth: H = L0 – preload – stroke

3. Materials used for the line fittings

Example

The product is externally threaded and can normally be moulded in a line position, but not in all cases. So use the exit angle to analyse whether there is a backlash in the direction of the line exit. What is the amount of backlash? If it is three or more C’s see if the product tolerances are offset.