Honeycomb drawer product is shown in Figure 1. Maximum size of product is 120.00 mm * 88.50 mm * 32.20 mm, average thickness of plastic part is 3.00 mm, material of plastic part is PC+ABS+PTFE, shrinkage rate is 1.0045, and weight of plastic part is 55.64 grams. Technical requirements for plastic parts are that there must be no defects such as peaks, underfilling of injection molding, flow lines, pores, warpage deformation, silver streaks, cold materials, jet lines, etc.

 

It can be seen from Figure 1 that plastic part is shaped as a flat drawer-shaped shell. Shape of front and rear molds is roughly symmetrical. There is an elastic tongue on one side of plastic part, and slider core needs to be designed here. Plastic part material is PC+ABS+PTFE, among which PC+ABS is commonly known as plastic alloy. This material not only has excellent heat and weather resistance, dimensional stability and impact resistance of PC resin, but also has excellent processing fluidity of ABS resin. Therefore, it can be used in thin-walled and complex-shaped products to maintain its excellent performance and good injection moldability. PTFE has excellent chemical stability, and does not have any effect on concentrated acids, concentrated alkalis or strong oxidants, and even "aqua regia" even at high temperatures. Friction factor is only 0.04. It can be used as an oil-free lubricating material for offshore oil drilling derrick slide rail veneer, dock slide veneer, river dam gate slide veneer, bridge telescopic support slide veneer, sliding guide veneer and lubricating board of various lathes, boring machines, grinders, planers, and stripping mold plates for manufacturing laminates and decorative boards. After adding PTFE, coefficient of friction of honeycomb drawer is small, product is wear-resistant, and various electrical properties are good.

 

 

 

 

 

 

Figure 2 Mould diagram of honeycomb drawer
Plastic parts are produced in large batches, mold design cavity is ranked as 4 cavities. See mold design diagram 2. Glue feeding method is a three-plate mold point gate, gate position is on the top surface of plastic part, and glue is fed in one point. Parting surface selection of mold. For this kind of plastic part, parting surface is very simple, it is a plane, located in the center of plastic part, and difficulty lies in the choice of mold opening direction. When size and shape of movable mold side, fixed mold side of plastic part are roughly same, choice of mold opening direction of plastic part is very important. Selection of mold opening direction is related to various issues such as whether plastic part will stick to mold, whether plastic part will be difficult to demold when mold is opened.
This set of molds choose to design one side of elastic tongue in movable mold, there are two main factors. First, it is convenient to design lateral parting and core pulling mechanism. Elastic tongue is on the side of movable mold. Movable mold slider is designed, which is simple and reliable. Second factor is that due to influence of elastic tongue and the other two bone positions, elastic tongue is designed on movable mold side, packing force on movable mold side is greater than fixed mold side, and plastic parts are not easy to stick to fixed mold.
Mold base is DCH5080, mold is American mold style, and mold base adopts a straight mold base. Mold is large, mold core is divided into two pieces, and fine frame is also two. Sliders are located on both sides of operating side and non-operating side, die core is positioned by heaven and earth side squeezing block when entering frame. At the same time, two inclined positioning blocks are designed on heaven and earth side to provide secondary positioning for mold. Mold steel is S-7, which is chromium steel used for molds in United States. This material has a heat treatment of 54-56HRC, has better toughness than 8407 and 2344. It is a commonly used material for long-life molds.
All sliders are driven by two oblique guide posts. Slider insert 19 is set on the slider seat 18 as a step. Design of slider separate inserts mainly considers ease of processing, and secondly considers ease of designing fixing of water transport rubber ring ; Inclined wedge 15 extends to movable mold as a backhoe mechanism to ensure reliable clamping of slider.
Plastic parts are ejected by a thimble. American customers generally require thimble to be plated with titanium to extend life of thimble.