[background technology]
Traditional injection molding process all is to take mold cold to heat and then cool cycles cycle to finish at present, and traditional injection molding process has following defective:
1, can only keep constant mold temperature, mold temperature can not surpass the thermal deformation turning point of resin, in case mold temperature surpasses the thermal deformation turning point temperature of institute's moulding resin, profiled member just can't solidify or need solidify oversize cool time;
2, when the forming plastic cement product, can't eliminate the folder waterline of surface of plastic product, also can't improve the glossiness of surface of plastic product, promptly use the die surface of Gao Guang also to have no idea to reach the effect of Gao Guang;
3, when moulding contains the resin of metal powder, can't eliminate the strip metal vestige of precipitation, also can't reach the metal surface effect of light;
4, when moulding contains the resin of carbon fiber or glass dimension, can't eliminate the folder waterline of its product surface equally, also can't improve the glossiness of its product surface, promptly use the die surface of Gao Guang also to have no idea to reach the effect of Gao Guang.
5, when the die cast metal processing and forming, can't reach the effect of quick cooling, cause the metal casting excessive cycle.
[summary of the invention]
The objective of the invention is in order to have overcome shortcoming of the prior art, provide a kind of and can effectively improve moulding product quality and output, be suitable for multiple injection moulding material and improve the fast cold injection molding process of hot-die and the equipment thereof of traditional injection moulding technology deficiency.
The present invention realizes by following scheme for achieving the above object:
The fast cold injection molding process of hot-die, its preparatory items comprise:
● start the cold high pressure radiator cooler;
● start the mould temperature controller and give the heating of the heat carrier in the die;
● set the temperature value of the thermal source in the die;
● set die to the processing temperature of resin and the solidification temperature of resin;
● set the resin melt temperature;
● the molding parameter;
● connect the interlocking signal between high pressure cooling system and the injection moulding machine.
More than the setting of all temperature all need to set different temperature according to different resins.
The fast cold injection molding process of hot-die is characterized in that described technology may further comprise the steps:
A, adopt the resin drying oven that resin is dried, the resin of oven dry is sent into melten gel material pipe by the resin hopper, add PUR material pipe to the melt temperature of resin and make resin reach molten condition;
B, startup cooling tower are prepared cooling water, with the processing temperature of mould temperature controller preheating die to setting;
C, when the die temperature is higher than the processing temperature of setting, can regulate the high pressure cooling system of cooling water circulation rate and cooling water temperature with the control of PLC control terminal and prepare water at low temperature, open injection moulding machine mould is closed, the injection system of control injection moulding machine carries out injection;
D, when the die temperature is higher than 5 ℃ of the processing temperatures of setting, control high pressure cooling system is annotated the water at low temperature cooling to die, when the die temperature drops to resin softening point with when plasthetics solidifies, control high pressure cooling system stops to annotate water at low temperature to die and lowers the temperature;
E, startup injection moulding machine die sinking system opening mold take out plasthetics.
The fast cold injection molding process of aforesaid hot-die, the resin moisture that it is characterized in that drying among the described step a is less than 0.02%.
The fast cold injection molding process of aforesaid hot-die is characterized in that the temperature of water at low temperature in the described steps d mesohigh cooling system is set at 5-90 ℃.Need temperature according to different resins and energy saving technology requirement setting water at low temperature, wherein said high pressure cooling system is the number of patent application of the applicant in application on July 20th, 2010: 201020271728.5 " a kind of injection mold temperature control system ", this system can produce 0 ℃ water at low temperature.
The fast cold injection molding process of aforesaid hot-die when it is characterized in that described temperature when water at low temperature in the high pressure cooling system is higher than setting value, is opened cooling tower water intaking valve and outlet valve carry out inflow and outflow of water and cooling for reflux to the high pressure cooling system water.Be provided with wind force device in the described cooling tower and can carry out nature to the hot water that refluxes back and be cooled to 30 ℃, be adjusted to the temperature of required water at low temperature again by high pressure cooling system 2.
The fast cold injection molding process of aforesaid hot-die, the processing temperature setting range that it is characterized in that die among the described step b are at 60-400 ℃, and the heat source temperature in the die is set at 300-600 ℃.Need to set different processing temperatures according to different resins.
A kind of mould that is used for the fast cold injection molding process of above-mentioned hot-die, comprise die behind the front mould Renhe, form die cavity behind the die matched moulds behind the front mould Renhe, it is characterized in that being respectively equipped with in the die behind the described front mould Renhe and be used for to the heater of die heating and be used for cooling device, on die behind the front mould Renhe, be provided with the thermal insulation board of avoiding thermal loss to the die cooling.
Aforesaid a kind of mould is characterized in that described heater is arranged on the interior side near thermal insulation board of die behind the front mould Renhe, and described heater comprises heat carrier, is provided with thermal source in described heat carrier, and this thermal source is an Electrothermic wire.
Aforesaid a kind of mould is characterized in that described cooling device comprises some cooling water channels, and described cooling water channel is arranged between heater and the die cavity near in the die behind the front mould Renhe of die cavity one side.
Aforesaid a kind of mould is characterized in that described thermal insulation board is ten, is separately positioned on the outer surface of die behind the front mould Renhe.
Aforesaid a kind of mould is characterized in that the distance between described cooling device and the heater is the twice of the distance between the plasthetics surface in described cooling device and the mould.
Adopt technological process of the present invention, mainly contain following some advantage:
1, improved the die cavity internal mobility of molten condition plastic cement at high-temperature, make that the plastic cement molecular distribution of molten condition is more even, reduced the die cavity internal pressure, reduced and filled needed injection pressure, reduce the internal stress of plasthetics, reduced needed clamp force.
2, increased the glossiness on plasthetics surface, embodied the effect of one-level minute surface fully for the mould of Gao Guang, eliminated the folder waterline on plasthetics surface, can make forming plastic cement product surface naked eyes vision not have weld bond, microscopically at 100 times of focal lengths be can't see weld bond, can omit simultaneously the surface spraying of plastic cement products, make high light surface of plastic product directly reach high light effect.
3, the present invention can eliminate the inner residual internal stress of plastic cement products, avoids the back cracking of plastic cement products; Be applicable to high finish surface plastic parts and line face product.
4, the present invention can make the various engineering resin moulded products that contain metal dust can't see weld bond and the black seal of strip.
5, the present invention is applicable to glass dimension potting resin, filled with carbon fibers resin, thermosetting resin, the moulding of metal powder potting resin; Be applicable to metal injection molded moulding, die cast, foaming, nitrogen assistant formation, the present invention is applicable to all types of injection mo(u)lding injection machines.
6, the present invention can cover injection mold heating or refrigerating function separately; In same molding cycle, can start the cooling periodic duty that heats up, reach the shock heating quenching effect of injection mold.
7, cost of the present invention is low, can substitute quick cold and hot moulding process.
8, the engineering resin that is suitable for of the present invention comprises:
ABS (Acrylonitile-butadien-styrene) acrylonitrile/butadiene/styrene copolymer; ABS+GF (Acrylonitile-butadien-styrene+Glass fiber) acrylonitrile/butadiene/styrene copolymer+glass; PMMA (Poly-methyl-methacrylate) polymethyl methacrylate; PMMA+ABS (Poly-methyl-methacrylate+Acrylonitile-butadien-styrene) polymethyl methacrylate+acrylonitrile/butadiene/styrene copolymer;
PMMA+PC (Poly-methyl-methacrylate+Poly-carbonate) polymethyl methacrylate+Merlon; PC (Poly-carbonate) Merlon; PC+ABS (Poly-carbonate+Acrylonitile-butadien-styrene) Merlon+acrylonitrile/butadiene/styrene copolymer;
PC+ABS+GF (Poly-carbonate+Acrylonitile-butadien-styrene+Glassfiber) Merlon+acrylonitrile/butadiene/styrene copolymer+glass; PC+GF (Poly-carbonate+Glass fiber) Merlon+glass; PA (Polyamide/Nylon) polyamide/nylon; PA+GF (Polyamide+glass fiber) polyamide+glass; PA+CF (Polyamide+Carbonfiber) polyamide+carbon fiber.
[specific embodiment]
Below in conjunction with accompanying drawing the present invention is done further detailed description of the process.
As illustrated in fig. 1 and 2, the fast cold injection molding process of hot-die, it may further comprise the steps:
Adopt resin drying oven 6 that resin is dried moisture and be lower than 0.02%, the resin of oven dry is sent into melten gel material pipe 15 by resin hopper 5, add PUR material pipe 15 and make resin reach molten condition; Start cooling tower 1 and prepare cooling water, generate heat to design temperature, reach the processing temperature of setting for to die 9 surfaces die 9 preheating dies 9 thereby add thermal conductor 96 heat transfers with mould temperature controller 7 control thermals source 98.
When die 9 temperature are higher than the processing temperature of setting, control PLC control terminal 8 starts the high pressure cooling system 2 that can regulate cooling water circulation rate and cooling water temperature and prepares water at low temperature, open injection moulding machine 3 mould 4 is closed, the injection system 31 of control injection moulding machine 3 carries out injection; When die 9 temperature are higher than 5 ℃ of the processing temperatures of setting, transmitting signal makes high pressure cooling system 2 annotate the water at low temperature cooling for die 9 for PLC control terminal 8, water at low temperature flows out from high pressure cooling system 2 and enters die 9 through water at low temperature flowing water Valve 13, flow out from die 9 again, get back to high pressure cooling system 2 through water at low temperature backwater valve 11, circulation cooling so repeatedly, when die 9 temperature drop to below the resin softening point, plasthetics 14 in the die 9 solidifies, and transmits signal and makes high pressure cooling system 2 stop to annotate water at low temperature to die 9 for PLC control terminal 8; Start injection moulding machine 3 die sinking system opening molds 4, take out plasthetics 14.
The temperature of water at low temperature is set between 5-90 ℃ in the described high pressure cooling system 2, when the temperature of water at low temperature in the high pressure cooling system 2 is higher than setting value, open the water that 10 pairs of high pressure cooling systems of cooling tower water intaking valve 12 and cooling tower outlet valve, 2 interior water at low temperature are carried out inflow and outflow of water and cooling for reflux.
As shown in Figure 3, a kind of mould that is used for the fast cold injection molding process of above-mentioned hot-die, die 91 and back die 92 before comprising, form die cavity 90 behind preceding die 91 and back die 92 matched moulds, before described, be respectively equipped with the heater 93 and the cooling device 94 that is used for to die 9 coolings that is used for to die 9 heating in die 91 and the back die 92, on preceding die 91, back die 92, be provided with thermal insulation board 95.
Form die cavity 90 behind die 91 and back die 92 matched moulds before described, inner surface for die 9, five faces beyond preceding die 91 or the back die 92 upper cavities 90 place faces form the outer surface of dies 9, described thermal insulation board 9 is ten, be used to avoid temperature loss to keep the temperature of die 9, the temperature of die 9 is all distributed when avoiding to die 9 coolings, is separately positioned on preceding die 91 and back die 92 outer surfaces.
Described heater 93 is separately positioned near in the preceding die 91 of thermal insulation board 95 1 sides and the back die 92, comprises heat carrier 96, in described heat carrier 96 Electrothermic wire is housed.Described heat carrier 96 is the material of copper billet or other good heat conductivity, and described Electrothermic wire is common 220V or the Electrothermic wire of 380V, and power bracket is between 1KW to 10KW.
Described cooling device 94 comprises some cooling water channels 97, is arranged in the preceding die 91 and back die 92 of close die cavity 90 1 sides between heater 93 and the die cavity 90.Punch at the 3-9 millimeter place that preceding die 91, back die 92 are pressed close to die cavity 90 and to add cooling water channel 97, the distance between cooling device 94 and the heater 93 is the twice of the distance between cooling device 94 and plasthetics 14 surfaces.
As shown in Figure 4, described heater 93 and cooling device 94 also can be provided with like this, punch two round positions in preceding die 91, back die 92, near row's connection cooling water channel 97 of die cavity, near the electric heating tube of packing in another row of thermal insulation board 95, the power of every electric heating tube is not higher than 1KW.
When mould 4 closures, the die 9 that die cavity 90 is arranged in preceding die 91 and back die 92 formation closed together, after the injection, die 9 temperature continue to rise, when die 9 surface temperatures surpass 5 ℃ of processing temperatures, injecting water at low temperature in the cooling device 94 begins plasthetics 14 coolings, when reducing to the following resin solidification of resin softening point, stop to inject the water at low temperature cooling, because of cooling device 94 close plasthetics 14, away from heater 93, during cooling die 9 peripheral temperature than the temperature around the plasthetics 14 descend slow, the temperature of thermal source 98 is far above the temperature of heat carrier 96 outer dies, after stopping cooling, close water at low temperature flowing water Valve 13, close once more in the process of mould at mould 4 die sinkings taking-up plasthetics 14 and mould 4, die 9 temperature in the heat transmission of thermal source 98 can continue to go up to setting value beginning injection moulding next time.