Solid State Relays (SSR) & magnetic proximity sensors by celduc PLASTIC INDUSTRY

Solid State Relays (SSR) & magnetic proximity sensors by celduc PLASTIC INDUSTRY

Injection & moulding machines a) Two processes : injection & moulding INJECTION The thermoplastic material is melted inside the nose of the injection machine and carried inside the mold with a screw: Temperature : according with the material : 220 C up to 350 C Pressure to push the plastic inside the mold: 250 to 400 Kg/cm² The mold is cold or a little bit warm : 20 C to 70 C The mold owns a water circulation to keep it cold The plastic material warmed up to 220 C to 350 C goes into the mold and becomes hard because of the cold mold s temperature. PS: when the finished product is out from the mold, it can be melted again if you warm it up, and becomes more and more liquid. We can find through the world a large choice of people making injection molding machine for plastic part : Sumitomo, Nissei, Billon, Sandreto, Sidel, Husky, Engel, Netzal, Aoki, ASB.. SC9 / SO9 used to switch On & Off the heater around the screw which carries the plastic material : Typically : SC941160 & SC962160 Infra red lamp on each side of the preform track is driven by phase angle controllers SG5 : on this example 16 IR lamp means 8 SG4 / machine a SG4 drive 2 IR lamp Lamp power : 500W / 1000W / 1500W

Example : PET injection machine In this example, the thermoplastic material used for water bottle is a PET. First with a classic injection molding machine a preform is injected inside a cold mold, then the preform is unloaded from the mold, warmed up again with Infra Red lamp, then put inside a mold with a bottle cavity and hold by his screw nose, blowing with hot air and stretching to get a water bottle. MOULDING The thermoplastic material is a powder which is pressed to get a pellet. A pellet is made from powder inside a tool with a huge pressure to compress the powder and get a preform which seems like an aspirin tablet. The size of this pellet depends on the size of the finished product which will be encapsulated. This technology is used mainly for semiconducteur parts: triac, transistor, memory, processor, diode, Reed relays, SOT 23 ( SMD component). Several «Lead Frame» after «encapsulation with thermosetting material

The thermosetting pellet is sometimes preheated up to 80 C sometimes only pushed inside the hot mold and melted against the hot wall of the mold: Temperature of the thermosetting material : 20 C up to 80 C Temperature of the tool mold: 170 C up to 200 C Pressure to push the thermosetting inside the mold: 15 to 30 Kg/cm² The mold owns a heating system integrated or not inside its base, it s the case for large molds. For automatic molding sytems, the table on which the molds tools are moving is maintained hot with heaters. Anyway we find an accurate heating regulation to maintain the mold at the right temperature which depends on the material. The thermosetting material (phenols Epoxy, Diallil phtalate ) is pushed by the plunger inside the hot mold. In contact with the hot mold, the thermosetting material melts and goes inside the runner to get the cavities and encapsulates the insert put inside the mold with a frame or without frame which depends on the two types of process. We can find through the world a few companies making automatic molding machine for semiconductor parts : FICO in Netherlands, one in Japan, HULL in scotland, Lauffer in Germany.Krass corp in USA..These main players have to be found because the semiconductor market is huge and a lot of molding system is sold through the world. celduc uses this technology to make the encapsulation of the Reed relays M60 & D31A, so we know exactly what a customer is looking for. b) Why using SSRs? The main trouble on the large mold 400 cavities is a broken heater. As there are 6 to 10 heaters spread inside, it s not easy to check a heater broken through the other because the temperature up the wrong heater drops down 3 or 4 degrees..no more but enough to have some trouble shooting with small bubbles inside the encapsulation. So our new SSR with Diagnostic which is able to give information about the status of the output must be welcomed by the manufactures of these systems. If this heater is broken, means open. It doesn t warm and the temperature of the mold just up the heater drop down 2 or 3 C only...enough to have some trouble 10 Heaters 500W to 1000W inside the top and bottom part of the mold means 20 heaters Bottom mold Bottom part of the mold

Extruders a) The process Long used with other materials, extrusion techniques have become widespread when applied to the processing of thermoplastics. The extrusion process consists in continuously forcing a heat-softened plastic through a die which will determine the cross-section of the profile after cooling. This is achieved using single- or double-screw extruders where screws rotate inside a heated cylinder. Based on time-honoured trade practices, the art of extrusion has now progressed further through continued research. The continuous nature of the process is conducive to high productivity following time-consuming and delicate adjustments.

Using any single type of basic equipment, the multiplicity of dies developed in our Industry keeps expanding the range of products available in extruded form. Extruded profiles currently represent 40% of thermoplastic end products. b) Compound manufacturing Compound manufacturing is a two-stage process, which includes formulation and production. The result is an intermediate between the raw materials and the end product. Formulation, the determination of the nature and proportions of the materials and additives to be used, is an essential step in compound development. Individual formulations, specific to one client or product line, must meet a number of requirements at the preparation stage, before they are put into production in the form of granulates or dry-blend, usually coloured in the wass. Production requirements generally relate to colour, appearance, elasticity, stiffness, impact properties, resistance to chemicals, light resistance and thermal cycling resistance. These properties must remain unchanged throughout product life. c) Profiles and applications Thermoplastics are extruded through dies into a variety of profiles for use in areas such as the building and furnishing trades, the automotive industry, leisure products, agriculture, medical applications, electronics, communications, aeronautics, advertising signs and many more. -Building and furnishing trades The multiplicity of PVC window applications requires a wide range of compatible profiles with frequently complex sections. The success of the extrusion process in responding to such demands accounts for the enthusiastic adoption of extruded profiles by the building trade. Gates, fences, wallcovering, rollshutters, skirting, wireways and cable trays are also available in extruded form. -Automotive industry Vehicle side protection and wire ducts are extruded products. -Products for leisure and agriculture All skiers are familiar with plastic slalom poles. They are made by extrusion, as are greenhouses, stables, stakes, garden furniture, turning-slat signs and many other items. Extruded profiles are part of our everyday life, and their qualities contribute to its improvement.

d) The SSR s function into the extrusion process Just like the injection process, the SSRs make an accurate temperature control possible. Indeed, in this case as well, the plastic material has to be soft enough, which means between two accurate temperature levels. The temperature control thermocouples are made up of two different metals soldered between each other. Due to this dissimilarity, electrical pulses which are commensurate with temperature, are sent to a system controlling the SSR. The extruders produce, amongst other things, cables. The die is dedicated to lay out the plastic coat. The cooling fixture is the result of the customers requirements in terms of accuracy. It allows a better accuracy. Filière Conformateur (réglage précis des dimensions de la couche plastique) Safety sensors Ensure the safety of machine operators and machine operating reliability!

The PXS or PSS ranges are safety sensors used to give an emergency signal and / or stop dangerous machines when protective devices, machine casings or door are open.