Hardware mold design

Design Preparation
1. Confirmation of necessary drawings and the contents of the sample book:
The following drawings or documents are usually required before the formal design of the mold:
(i) part drawing; (ii) sample of gold model design and production; (iii) design and production contract; and (iv) other documents.
The above information must be fully understood, and any ambiguities must be confirmed by the customer.
2. Grasp the outline of the drawing
The part drawing determines the final purpose of the design and must be understood thoroughly. The part drawing provided by the Japanese customer is drawn using the triangular method in accordance with the JIS drawing regulations, and usually consists of the following parts:
Front view, Plan view, Side view, Section view, Detailed view, Reference view, Notes, Tolerance list, List of markings, Title bar, Others.
Pay attention to the following aspects in the view process:
① Tolerance requirements are more stringent; ② the parts that have an impact on the structure of the metal type;
(ii) The part that cannot be understood from the existing drawing; (iv) Matters highlighted in the notes.
⑤ Special material and heat treatment requirements; ⑥ Thin wall thickness of parts (t <0.6mm)
(vii) Thick wall thickness of parts; (viii) Whether the appearance of special sample requirements
⑨ three-dimensional surface part; ⑩ designer, date, period, price, etc.
3 parts of the understanding of the three-dimensional shape
Parts of the drawing is a two-dimensional drawing, to be converted into three-dimensional shape in the mind of the designer through the view, and hand-drawn three-dimensional drawing is very helpful.
Prepare paper and pencil.
First, draw the general outline of the product, and then draw the cross-section of each part of the product according to your understanding of the part drawing.
This is important for determining the parting surface and dividing the part in the future. If conditions permit, it is better to use aids such as clay to aid understanding.
4. Review of the title bar
The title bar of the part drawing usually indicates the tolerance in the drawing, the material of the part, and other contents, which must be read carefully.
① part name; ② figure name; ③ figure fan; ④ material (including shrinkage); ⑤ sample, refers to the details of the material sample, such as manufacturers, trade names, resin code; ⑥ scale; ⑦ designer; ⑧ change column;
5. Note part of the review
(1) gate type, location, number
If there is no special requirement, the gold mold designer needs to obtain the customer's consent after deciding on his own.
(2) Requirements for the sub-dividing line
Since the sub-separation line will form a mark on the surface of the product, which affects the appearance and is especially harmful to the folded part, the designer should comply with the regulations of the part drawing.
(3) Requirements for defects such as scratches on the surface of molded products
The designers of the molded parts shall avoid the design of the structure of the molded parts in which the above defects may occur.
(4) Requirements for unannotated tolerances
(5) Changes in the shape and size of molded products must be approved by the customer, and the mold designer must not make decisions on his/her own.
(6) Review of the main view
The main view is the place where the dimensions of the drawing are concentrated, and we confirm the tolerance on both sides and the tolerance on the side of the sheet, and mark the stricter ones.
(7) Review of other views. The method is the same as above.
(8) Review of the necessary molding force
When the molten resin is injected, a large injection pressure is generated on the parting surface of the mold. If the maximum force of the injection machine is less than the injection pressure, gaps will be created between the moldboards, and edge overflow will occur. Calculation of the necessary force is as follows:
F=P×A F: Necessary type bonding force (Kg)
P: injection pressure (Kg/cm2), take 300 ~ 500, depending on the molding conditions
A: the projected area of the product in the direction of injection cm2
(10) Review of necessary injection volume
When selecting the injection molding machine, it is necessary to review the injection volume.
The sum of the volume including the chat and the product should be less than 1/2 to 2/3 of the maximum injection volume of the injection machine.
(11) Other matters
If the information provided by the customer is incomplete, it is necessary to contact the customer to obtain all the information.
Use colored pens to mark the ones you think are more important for the next step of the design.