JPH07505096A - Delivery and mixing systems for multicomponent molding compounds - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Feeding and mixing systems technology for multicomponent molding compounds The present invention feeds a plurality of different ingredients into a molding machine in controlled amounts and composition states. Regarding the system. More particularly, the present invention provides a method for combining a plurality of different particulate molding composition components. to maintain the dryness of this component throughout the system and the uniformity of all components. This particulate component is blended in order to obtain a mixture of and a system for feeding this mixture to a molding machine.

Background of the invention Feeding multiple different ingredients into a molding machine in the exact amount and desired state is a problem. It is. This problem involves large parts, which are used in large numbers in automotive applications. This is further increased during molding operations, especially when molding parts reinforced with glass fibers. It will be done.

The use of renewable thermoplastic polymers becomes increasingly important in the field of molding large parts It has become to. These polymers are prone to hydrolytic degradation at molding temperatures. and must be delivered to the molding machine in a dry state.

The glass fibers used to strengthen molded parts are supplied by the manufacturer in the form of cut bundles. Delivered in Handling, especially when mixing and feeding the glass fibers into the forming machine. This bundle tends to change suddenly, forming a fuzzball. Ru. This pilling causes overgrowth of glass fibers that can block the system and impair the performance of the molded product. Generates surplus area. Fine fibers from dismantling the bundle are removed from the air filter and Block transportation lines.

The system of the present invention combines multiple ingredients in precise proportions while simultaneously drying 11Drying of the contained ingredients during allocating, transporting, mixing and feeding operations can be maintained.

Summary of the invention The system of the invention comprises a plurality of holding boxes for particulate molding material components. . Each component requires its proper dryness. Separate drying hoppers for each component It is provided. Each hopper receives conditioned air, i.e. dehumidified air at a temperature Unique heater control system that adjusts temperature before introducing it into individual drying hoppers It has a location. The transport system from the drying hopper to the molding machine has a coordinated Air is supplied.

Utilizing dehumidified air provided by dehumidifying dryers, filters and compressors Contains a pneumatic transport loop. The drying hopper for each ingredient includes a compact A smaller residual supply box (inventory 5up) that is part of the metering unit ply bin) to allow loading of the evacuated contents with dry air for transport. A special discharge valve is installed. These boxes separate the shipments from each box. Suspended in a precise weighing strain cell (weighing 5 train cell) A vibrating pan type feeder (vLbratory pan) that distributes to the weighing hopper (feeder) by gravity. The weighing hopper consists of a weighing cell and a vibrating plate type feeder. With automatic feedback control between amplitude and timing controller to feeder , filled to their exact weight.

Transport hoppers handle components with widely different physical and handling properties. Designed with steep sides for easy handling. Typically the hopper is an oval A vertical front wall and a steep slope (7 0 degrees).

The pre-weighed components are then pneumatically conveyed (venturi) using conditioned air. ) system to a holding hopper located near the molding machine.

The particulate component, pre-metered and held in a holding hopper, is released into a mixer. . Releasing the fine particles into the mixer before introducing the glass fibers This is important to eliminate excessive turning, which may result in "pilling".

The glass fiber component prevents the glass fiber bundle from becoming fibrillated and prevents the formation of "pills". treated in a very special and careful manner to prevent this. shredded glass fiber The fiber is in a bulk container, preferably a large container weighing generally 1000 to 2000 lbg. received from a large bulk bag feeder. Glass fibers follow control set points. and according to set ratios and set ratios for other compositions to reach the correct weight. is fed to the weighing hopper until the When commands are given from the central control station, The discharge gate of the glass fiber metering hopper is opened. At the same time or almost simultaneously The gate valve of the purified air seal is opened and the metered glass fiber charge to the mixer begins. Filling is allowed.

Reinforcing components in addition to or in place of glass fibers are used in the system. Good too.

The ingredients are mixed approximately above the molding machine. Internal lifting and orientation are elements Horizontal shaft type mixer with limited rotation and controlled speed of the device All ingredients in the mixer are gently brought together to create a homogeneous mixture. so that it is rotated to To unravel the glass fibers and place them downwards into the mixer, Separating and handling the glass fibers using only gravity (excluding the feeder) It is important to maintain the integrity of the fiber bundles and thereby minimize fibrillation. one Once the required number of revolutions of the mixer has occurred in order to obtain a homogeneous mixture, the central control system On command from the The port can be opened. This ensures that a well-mixed ingredient charge is placed in the holding hopper and and into the throat of the molding machine. Place the mixer almost above the extruder By doing so, separation of components due to differences in solid flow characteristics of the components may occur. do not have. (The homogeneity of the mixture is formed by plug flow.) It is maintained until entering the aircraft. Glass breakage and “pilling” formation is kept to a minimum and This improves the performance of molded parts.

Brief description of the drawing The figure is a schematic diagram showing a preferred embodiment of the component supply system according to the invention.

Detailed description of the invention Referring to the figure, a plurality of particulate molded compound components are placed in holding boxes 10.12.14 and 10.12.14. and stored in 16. This component is supplied to the feed line 20.22.24, and a drying hopper 30, each equipped with individually controlled heaters via 26; 32, 34, and 36. Conveying air is routed from the main dryer unit 28. It is fed to the drying hopper via the inlet 18. Conditioned (dry) air is dried From machine 110 to conditioned air supply lines 120, 122, 124, and 126. Drying hopper via arranged heaters 112, 114, 116, and 118 - supplied to

The particulate component is made of thermosetting polymers such as polyester and polyamide, as well as reinforcing materials and Such as , viscosity reducer, colorant, mold release agent, antioxidant, ultraviolet light stabilizer, flame retardant It may also contain additives. polyethylene terephthalate soft drink bottle Recycled thermoset polymers, such as post-consumer recycled bottle resin, can also be used. can be used. When the ingredients reached the desired level of dryness, they were adjusted The residual supply box (1n inventorysupply bin) 50, 52, 54, and 56 be done. Each box should have one vertical wall and a sharp corner to facilitate the excretory flow of its specific contents. A side wall with a degree is used. Each feeder receiving boat is coated It is loosely connected to the individual feed boxes via a flexible sock and similarly connected to its output. At the mouth, ingress of indoor air, excessive loss of purified air, and leakage of particulate matter are connected to the weighing hoppers 60 and 60' to prevent

By commands from the central control unit, weighing units 48 and 48' A predetermined amount of the ingredient is delivered to the metering hoppers 60 and 60' to be metered. Ru. Each hopper carries the exact weight of these ingredients designated to pass through it. 1 suspended in controlled weighing cells 58 and 58' to give e.g. , the total loading is 3 from residual supply boxes 50, 52, 54, and 56, respectively. 50 lbg (22,7 kg) consisting of 5%, 35%, 25%, and 5% ingredients ). Separate weighing hoppers 60 and 60' allow for simultaneous weighing. This results in an increase in cycle speed. The feeder of the weighing unit is a spiral groove type. Although an auger feeder may be used, a covered pan type high frequency vibration feeder may be used. A dynamic unit is preferred. Dish type feeder provides extremely uniform lip area under precise control While the spiral groove feeder has the general advantage of providing a uniform distribution, each groove It has the disadvantage of slightly slugging when the material is dispensed from the pitch. ing. As a result, the accuracy range of each helical groove type is more limited than that of a vibrating dish feeder. It will be done.

Weighing hoppers 60 and 60' are provided with weighing cells and vibrations for their precise weight. Automatic feedback control between the plate feeder's amplitude and timing controllers provides Filled. Two or more specified components are delivered sequentially to each metering hopper. It will be done. Both weighing hoppers can be operated sequentially or simultaneously. Weighing hopper When the specified weight of the load is obtained, the bottom flap of each weigh hopper is This charge is automatically removed by opening wrapper valves 62 and 62'. The scale is then dropped into the scale accumulation hopper 64. Weighing hopper, flapper bar The dry air is This merging means is supplied to prevent the ingress of air.

The hopper 64 is fed with widely varying physical and handling characteristics. Designed with steeply sloped side walls to properly handle the components . Typically, this hopper is elliptical-conical in shape, with a vertical front wall and a truncated oval section. It has a steeply sloped (70 degree) rear wall arranged in turns.

The pre-metered ingredients are transferred to a pneumatic conveyance (Venturi) system 66 using dry air. and a dryer disposed proximately above the injection molding machine 96 via the feed line 68. The air is transported to a holding hopper 70 for air purification.

The bulk bag 80, which is a source of glass fibers, is used in the upper structure 72 and the running lane 7. It is suspended from a holding rack supported by 4. Robot with long arm gloves ( using the long-armed glove entry port) 82. The drawstring on the bag 80 can be untied and the downspout of the bag is inside the funnel of the ejector 84. placed on the side. Large bags are tied together with a drawstring device and outer flaps characterized by a bottom seal consisting of an internal tubular funnel that is The outer flap is also activated with a drawstring device and tied with a knot. It's been revealed. The bag being filled retains a flexible rubber seal that wraps around the bag's discharge area. It is lowered onto the top surface of the discharge box 88 which has the same structure. Steep side walls and vertical walls of the discharge box However, the glass fibers are sent to a vibrating plate type feeder 85 with a cover sealed with a sock. let Through a sequence control station, this feeder separates the glass fibers into separate Direct it to the weighing hopper 86. This weighing hopper has a superstructure with a weighing cell. Supported by. Glass fibers are tested according to control set points and in combination with other components. is allowed to enter the weighing hopper 86 until the correct weight is obtained according to the determined proportions. has been done.

In addition to or instead of glass fibers, inorganic fibers and carbon fibers can be used. Reinforcing components such as bars and aramid fibers, mica, glass or ceramic spheres can also be used in this system and is fed to the weighing hopper 86 as described above. obtain.

The mixer 90 is located close above the feed throat of the machine hopper 94. . Residual feed hopper 50.52° from 54, and 56, and glass fiber feed The components delivered from source 80 are gently mixed together to obtain a homogeneous mixture. is then activated by the slide gate valve 92 on command from the central control station. It is discharged into the molding machine hopper 94. The mixer is placed above and close to the molding machine 96. This prevents separation of components due to differences in flow characteristics in the solid state of the components. It is not allowed to

Also, pilling and glass breakage are kept to a minimum.

It is important that the mixing of particulate components and glass fibers should be carefully controlled. . As previously pointed out, the fine particles should be fed into the mixer before the glass fiber feeding. However, with careful control, different materials can be fed into the mixer at the same time. good. A highly efficient magnetic grid 95 protects the system from mechanical disruption or with components. to remove any contaminants that may have entered the bottom of the machine hopper 94. It is located in the department. Using high-efficiency magnets, it is possible to increase the spacing between bars in the grid. and allow free flow of components.

The mixture of ingredients is fed in a plug (gravity) flow to a moving part 98 of an injection molding machine 96. . In the moving parts, plastic components are melted and mixed with other components. Afterwards, the mixture is fed to tool 100 to form a molded part.

This system distributes to the molding machine the exact amounts of various ingredients required for a specific product. can be fully automated and programmed to Successfully operate the system and quality An essential requirement to obtain good molded parts is the provision of dry air for the conveyance of the components. It is to do so. Air passes through supply line 102 and filter 78 to heat exchanger 10 Sent to 4. The main dryer unit 28 should distribute conditioned air to the system. It includes a dew point meter 106 and other controls. Dryer 108 with separate purified air can be supplied through supply line 38 by. A purified air dryer is a dehumidified air dryer. supply air to the various system units, thereby filling almost all interior spaces. Prevents air from entering the system.

Variations on this system are possible. For example, air supply and drying means can be Combined within the unit, the residual supply box supplies the particulate components to glass fibers. This can be omitted by directly feeding the relevant metering and merging means in the vicinity of the source. can. Accordingly, the invention departs from the principles of the invention set forth in the appended claims. It should be understood that this also includes embodiments that may be made without any modifications.

L@arbitrary judgment g cow Continuation of front page (72) Inventor: Lathrop, John, Francis United States of America 26181 West Virginia Washington Route 2 Box 60 (72) Inventor Maurer, Heinrich Federal Republic of Germany D-6390 Ufingeru Effi Bach Ufingeru; Trace 46 (72) Inventor Shin, Shikai United States of America 19317 Pennsylvania State Chappe Ford Power Lift The Pass

Claims (1)

[Claims] 1. A system that feeds multiple different ingredients into a molding machine in controlled amounts and composition states. a) a plurality of holding boxes for particulate forming composition components; b) said component (110); (112) [114) (116) (118) and apply the above to the entire system. means for keeping the ingredients dry; c) a bulk source (80) storing reinforcing ingredients; d) associated with said holding box and said ingredients; means (40), (42), (44) for feeding the weighing station (58), (58') )(46)(50)(52)(54)(56), e) a confluence comprising said metering station and achieving a predetermined mixture of said particulate components; Means (48) (48') (62) (62') (64), f) adding said particulate component and a controlled amount of reinforcing component to said component and said reinforcing component; feeding means for feeding the mixer (90) in which a homogeneous mixture is formed; and g) The mixture of the particulate component mixture and the reinforcing component is supplied to the mixture from the mixer. means (92) for releasing material into a hopper (94) for feeding said forming machine (96); A system that combines the following. 2. 7. The system of claim 1, wherein said reinforcing component is glass fiber. 3. The hopper (94) is located substantially above the molding machine (96). The system in the first term of the scope of demand. 4. The means for releasing the mixture of the particulate component and the glass fibers comprises and gravity feeding the glass fibers from the hopper (94) to the forming machine (96). 3. The system of claim 2, further comprising means for: