CN202344750U - All-electric miniature precise injection molding machine - Google Patents

Abstract

The utility model discloses an all-electric miniature precision injection molding machine, which belongs to the field of polymer material molding machinery. The miniature precision injection molding machine is mainly composed of an end face plasticizing part, a plunger injection part, a mold clamping part, a mold and a frame. The utility model adopts the side feeding method, the plunger, the machine barrel, and the hot runner nozzle are on the same straight line, and is equipped with a check valve, so that the injection resistance is small and the pressure loss is small; It solves the problems of difficult processing and low strength of the traditional small-sized screw; the servo motor is used to drive the ball screw pair to complete the injection of the plunger and the opening and closing of the mold, which can realize precise control of the action position and stepless speed regulation. The utility model combines the advantages of traditional micro-injection molding technology, end face pre-molding technology, hot runner technology and electric servo drive technology, and has the advantages of good plasticizing and mixing effect, high material utilization efficiency, small pressure loss and simple structure.

Description

An all-electric miniature precision injection molding machine

technical field

The utility model relates to a miniature precision injection molding machine, which belongs to the field of mechanical engineering for forming and processing polymer materials.

Background technique

Micro-injection molding technology is an important branch of MEMS. Micro-injection molding machine has become one of the main equipments of the world's manufacturing industry with the advantages of easy realization of low-cost mass production of precision micro-structure parts. Its main technological actions include mold closing, injection, pressure holding, cooling (simultaneous plasticizing and metering), mold opening and product demoulding.

Unlike traditional injection molding machines, micro-injection molding machines require high injection rates, precise injection volume metering and quick response capabilities. First, the high surface area/volume ratio of the product requires that the cooling of the product must occur in a very short time, so the nozzle must inject the material into the cavity as quickly as possible to ensure complete filling with a high aspect ratio feature. Second, the injection device must be capable of high injection pressures due to the need for precise feature replication. Finally, the injection process must be repeatable with high precision.

At present, commercial micro-injection molding machines can manufacture micro-products with volumes from 0.082 cm ³ to 8 cm ³ . Since micro-molding requires a small injection volume, the diameter of the screw should be reduced accordingly. At present, the minimum screw diameter is 12mm, and the smaller screw is easy to twist during the injection process. The injection unit can also adopt the plunger/screw compound type, and the clamping force can be as small as 70KN. The Boy12A injection molding machine of the German Boy Company adopts a hydraulic system, the screw diameter is 14mm (16mm, 18mm), the length-to-diameter ratio (L/D) is 18:1, and the injection volume is 0.1-5g. The TR20EH injection molding machine of Japan Sodick Company is an electro-hydraulic hybrid drive type, with a plunger diameter of 14mm, a stroke of 5mm, and an injection volume of 0.2g. The injection molding machine of Ettlniger Company in Germany has a coaxial screw/plunger compound injection unit, which can produce plastic parts of 0.1-5g. The Microsystem 50 of Battenfeld Company in Germany adopts a three-stage screw plunger type. The plastic particles are plasticized by the extrusion screw and metered by a pressure plunger. The precise quantitative resin is pushed into the injection chamber by the plunger and injected into the cavity.

Today, there are mainly three types of micro-injection molding equipment: screw type, plunger type and screw-plunger hybrid type. Screw-type micro-injection molding machine has the advantages of good plasticizing effect, but the small-sized screw has problems such as difficult processing, limited service life, long plasticizing time of molding materials and low utilization efficiency, and it is difficult to control the injection volume. The precision is poor; the control precision of the injection volume of the plunger type micro injection molding machine is higher than that of the screw type, but its plasticizing ability is low, the plasticizing uniformity is poor, and the plasticizing quality of the material is difficult to meet the requirements of high precision; the screw plunger hybrid micro injection molding machine Injection molding machines combine the advantages of screw and plunger models, but they still cannot get rid of the problems in the processing and use of small-sized screws.

Utility model content

The utility model provides an all-electric micro-precision injection molding machine, which combines the advantages of traditional micro-injection molding technology, end face pre-plastic technology, hot runner technology and electric servo drive technology, and has good plasticizing and mixing effects and high material utilization efficiency. The advantages of high pressure, small pressure loss and simple structure.

The utility model is an all-electric miniature precision injection molding machine, which is mainly composed of an injection part, a plasticizing part, a mold part, a mold clamping part and a frame, and the injection part, the plasticizing part and the mold clamping part are located on the frame. The plasticizing part is composed of machine base, plasticizing servo motor, plasticizing motor mounting plate, end screw plate, feeding hopper, heating plate, screw, machine barrel and check ball, etc. The plasticizing servo motor is installed on the plasticizing motor mounting plate through screws, and then the mounting plate is fixed on the machine base with screws; The output shaft of the motor and the end screw are connected by keys (single key, double key, spline, etc.), and the heating plate and machine barrel are connected by screws; the machine barrel and heating plate are tightly pressed on the machine base by screws; the hopper is installed on On the machine base, its axis coincides with the center of the inlet of the end screw; the material is fed from the hopper, and enters the Archimedes spiral groove opened in the end screw due to gravity, and then the molten melt enters the heating plate and Melt flow channels inside the barrel, followed by plasticizing metering. The injection part is mainly composed of injection servo motor, injection seat, coupling, ball screw, ball screw nut, push plate, plunger, injection rod, barrel and hot runner nozzle. The injection servo motor is installed on the injection seat through screws, and its output shaft is connected with the ball screw through a coupling, and the ball screw nut is fixed on the push plate; the coupling is fixed on the injection seat through rolling ball bearings and thrust bearings ; Both ends of the injection rod are respectively fixed on the injection seat and machine base by semicircular rod glands, and the push plate moves on the injection rod; the plunger is installed on the push plate, one end of which is close to the pressure sensor in the push plate, and the other end Melt channels extending into the barrel. The rotation of the injection servo motor drives the ball screw to rotate, so that the ball screw nut drives the push plate to move linearly on the two parallel injection rods, and the plunger installed on the push plate can move linearly in the barrel at the same time, and the injection is finally completed. Action; the forward and reverse rotation of the injection servo motor can realize the linear reciprocating motion of the plunger. The hot runner nozzle is installed on the barrel through the nozzle gland, and its axis coincides with the axis of the melt channel of the barrel; the hot runner nozzle is heated by a heating wire or a heating ring, and a temperature sensor and a pressure sensor are installed on it, which can detect the melt in real time The temperature and pressure are convenient for the adjustment and control of process parameters. The mold clamping part is mainly composed of the mold clamping servo motor, rear platen, moving platen, tie rod, ball screw, ball screw nut, coupling, clamping block seat, clamping screw and clamping nozzle. The machine base, moving platen and back platen are connected in series through four tie rods, and a wear-resistant bushing is set between the moving platen and the tie rods; the mold clamping servo motor is fixed on the back platen by screws, and its output shaft is passed through a coupling It is connected with the ball screw, and the ball screw nut is fixedly connected with the movable template through screws. The mold clamping servo motor drives the ball screw to rotate, so that the ball screw nut drives the moving template and the mold to reciprocate on the four pull rods, and finally realizes the mold opening and closing action. The mold structure of the mold part is basically the same as that of the traditional injection mold, except that there is a corresponding stepped hole in the center of the fixed mold, which is compatible with the structure of the hot runner nozzle; the width of the ejector plate is slightly smaller than that of the movable mold, which is consistent with the structure of the movable template . The fixing device of the mold on the template is composed of the clamping block seat, the clamping nozzle and the clamping screw. The front end of the clamping nozzle and the position corresponding to the mold have a slope structure, and the mold can be installed and disassembled by rotating the clamping screw. .

In the all-electric miniature precision injection molding machine of the utility model, the form of the end face spiral can be a single-entry Archimedes spiral, or a multi-entry Archimedes spiral, or other end face spirals. Screw groove form, as long as the plasticizing effect of the material can meet the molding requirements.

An all-electric miniature precision injection molding machine of the utility model, the heating plate is heated by a heating rod, and the temperature is measured by a thermocouple, and other heating methods can also be used.

An all-electric miniature precision injection molding machine of the utility model has no special product ejection mechanism in the mold clamping part, and the final ejection of the product depends on the retreat of the moving template and the relative forward movement of the ball screw when the mold is opened.

As can be seen from the above technical solutions, the utility model has the following advantages compared with the prior art:

1. The utility model adopts the end screw to plasticize the material, the material stays for a short time and will not decompose due to too long a stay time, and fundamentally solves the problems of difficult processing and low strength of the traditional small-sized screw.

2. The utility model adopts the side feeding method, the plunger, the machine barrel, and the hot runner nozzle are on the same straight line, and is equipped with a check valve, which has small injection resistance and small pressure loss; and the ball screw is used to drive the injection and measure High precision.

3. The utility model adopts a hot runner nozzle, so that there will be no cold material well and long main flow channel during molding, which greatly saves molding raw materials; and a pressure and temperature sensor is installed on the hot runner nozzle, which can monitor the melt pressure in real time and is easy to Real-time adjustment of molding process parameters to improve the repeatability of molded products.

4. The mold installation and fixing device of the utility model is driven by the locking screw to press the wedge-shaped mold pressing block nozzle to rely on the slope to press the mold, the mold is directly installed in the cavity of the fixed mold and the movable mold, and the installation and removal of the mold only need to twist the mold lock Tighten the screws, do not need to disassemble the mold pressing block frequently, and facilitate the standardization of micro-molds.

5. The power of the micro-injection molding machine of the utility model comes from the drive of the servo motor, which can realize the precise control of the action position and the stepless speed regulation of the motor, so the machine has strong adaptability to the types of molding materials and low noise.

Description of drawings

Fig. 1 is a schematic diagram of the overall front view of a micro-injection molding machine of the present invention.

Fig. 2 is an A-A sectional schematic diagram of the plasticized part structure shown in Fig. 1 .

Fig. 3 is a B-B sectional schematic view of the structure of the injection part shown in Fig. 1 .

Fig. 4 is a schematic sectional view of C-C of the mold clamping part structure shown in Fig. 1 .

In the figure: 1-injection part, 2-plasticizing part, 3-mold part, 4-mold clamping part, 5-frame, 6-plasticizing servo motor, 7-plasticizing motor mounting plate, 8-end screw . Thrust bearing, 19-Coupling, 20-Injection rod, 21-Ball screw, 22-Push plate, 23-Ball screw nut, 24-Clamping block seat, 25-Locking screw, 26-Clamping pressure Block nozzle, 27-mould, 28-hot runner nozzle, 29-nozzle gland, 30-tie rod, 31-plunger, 32-semicircle rod gland, 33-moving platen, 34-back platen, 35-mold clamping servo motor.

Detailed ways

As shown in Figure 1, the utility model is an all-electric miniature precision injection molding machine, mainly composed of injection part 1, plasticizing part 2, mold part 3, mold clamping part 4 and frame 5, injection part 1, plastic part Forming part 2 and clamping part 4 are positioned on frame 5.

Figure 2 is a cross-sectional view of the plasticizing part 2 (the left view of the cross-section of the hopper axis in Figure 1), the plasticizing part 2 is composed of a machine base 14, a plasticizing servo motor 6, a plasticizing motor mounting plate 7, and an end screw 8 , hopper 9, heating plate 10, screw 13, machine barrel 12 and check ball 11 and so on. The plasticizing servo motor 6 is installed on the plasticizing motor mounting plate 7 by screws, and then the mounting plate 7 is fixed on the base 14 with screws; the plasticizing motor 6, the end screw disk 8, the heating plate 10, the check ball 11 and The barrels 12 are connected in sequence, wherein the output shaft of the plasticizing motor 6 is connected to the end screw 8 by a single key, and the heating plate 10 and the barrel 12 are connected by screws; the barrel 12 and the heating plate 10 are tightly pressed on the machine base by screws 13 14; the feeding hopper 9 is installed on the machine base 14, and its axis coincides with the center of the entrance of the end screw 8; the material is added from the feeding hopper 9, and enters the Archimedes spiral that is opened in the end screw 8 due to gravity. Spiral groove, and then the molten melt enters the melt flow channel inside the heating plate 10 and barrel 12, and then performs plasticizing metering; the spiral groove form of the end face screw disk 8 is an Archimedes spiral spiral groove, and its end view It can be in the form of single inlet or multiple inlets; the heating plate 10 and barrel 12 are heated by heating rods, and the temperature is measured by thermocouples, and other heating methods can also be used.

Figure 3 is a sectional view of the injection part 1 (the top view of the center of the injection motor and the base in Figure 1), the injection part 1 is mainly composed of an injection servo motor 15, an injection seat 16, a coupling 19, a ball screw 21, and a ball screw. It is composed of lever nut 23, push plate 22, plunger 31, injection rod 20, machine barrel 12 and hot runner nozzle 28, etc. The injection servo motor 15 is installed on the injection seat 16 through screws, and its output shaft is connected with the ball screw 21 through the coupling 19, and the ball screw nut 23 is fixed on the push plate 22; the coupling 19 is connected by the rolling ball bearing 17 and The thrust bearing 18 is fixed on the injection seat 16; the two ends of the injection rod 20 are respectively fixed on the injection seat 16 and the machine base 14 by the semicircular rod gland 32, and the push plate 22 moves on the injection rod 20; the plunger 31 is installed on the push On the plate 22, one end of it is close to the pressure sensor in the push plate 22, and the other end stretches into the melt channel of the machine barrel 12. The injection servo motor 15 rotates to drive the ball screw 21 to rotate, so that the ball screw nut 23 drives the push plate 22 to move linearly on the two parallel injection rods 20, and the plunger 31 installed on the push plate 22 can be moved in the barrel at the same time. 14 linear motion, and finally complete the injection action; the injection servo motor 15 can realize the linear reciprocating motion of the plunger 31 forward and reverse. The hot runner nozzle 28 is installed on the barrel 12 through the nozzle gland 29, and its axis coincides with the melt passage axis of the barrel 12; the hot runner nozzle 28 is heated by a heating wire or a heating ring, and a temperature sensor and a pressure sensor are installed on it. The temperature and pressure of the melt can be detected in real time, which is convenient for the adjustment and control of process parameters.

Fig. 4 is a cross-sectional view of the mold clamping part 4 (the top view of the mold clamping motor and the center of the injection seat in Fig. 1), the mold clamping part 4 is mainly composed of a mold clamping servo motor 35, a rear template 34, a movable template 33, a pull rod 30, and a ball screw 21. Ball screw nut 23, shaft coupling 19, clamping block seat 24, clamping screw 25 and clamping block mouth 26 etc. are composed. The machine base 14, the moving template 33 and the rear template 34 are connected in series through four pull rods 30 in sequence, and a wear-resistant bushing is arranged between the movable template 33 and the pull rods 30; the clamping servo motor 35 is fixed on the rear template 34 by screws, Its output shaft is connected with the ball screw 21 through a coupling 19, and the ball screw nut 23 is fixedly connected with the movable template 33 through screws. The mold clamping servo motor 35 drives the ball screw 21 to rotate, thereby driving the movable template 33 and the mold 27 to reciprocate on the four pull rods 30 through the ball screw nut 23, finally realizing the mold opening and closing action. The mold structure of the mold part 4 is generally the same as that of the traditional injection mold, except that there is a corresponding stepped hole in the center of the fixed mold, which is compatible with the structure of the hot runner nozzle 28; The structure matches. The fixing device of the mold 27 on the formwork is composed of a mold locking briquetting seat 24, a mold locking briquetting nozzle 26 and a mold locking screw 25. The front end of the mold locking briquetting nozzle 26 and the position corresponding to the mold 27 have a slope structure, and the rotating mold locking screw 25 The installation and disassembly of the mold can be realized.

Claims (4)

1. An all-electric miniature precision injection molding machine, mainly composed of injection part, plasticizing part, mold part, clamping part and frame, injection part, plasticizing part and clamping part are located on the frame, it is characterized in that: The plasticizing part is composed of machine base, plasticizing servo motor, plasticizing motor mounting plate, end face screw, feeding hopper, heating plate, screw, machine barrel and check ball, etc.; the plasticizing servo motor is installed on the plasticizing motor through screws. On the mounting plate, fix the mounting plate on the machine base with screws; the plasticizing motor, the end screw, the heating plate, the check ball and the machine barrel are connected in sequence, and the output shaft of the plasticizing motor and the end screw are connected by a key. , the heating plate and the machine barrel are connected by screws; the machine barrel and the heating plate are tightly pressed on the machine base by screws; the feeding hopper is installed on the machine base, and its axis coincides with the center of the end screw disk inlet; the injection part is mainly controlled by the injection servo motor. , injection seat, coupling, ball screw, ball screw nut, push plate, plunger, injection rod, barrel and hot runner nozzle, etc. The injection servo motor is installed on the injection seat through screws, and its output shaft passes through The coupling is connected with the ball screw, and the ball screw nut is fixed on the push plate; the coupling is fixed on the injection seat through rolling ball bearings and thrust bearings; the two ends of the injection rod are respectively fixed on the injection seat by semicircular tie rod glands And on the machine base, the push plate moves on the injection rod; the plunger is installed on the push plate, one end of which is close to the pressure sensor in the push plate, and the other end extends into the melt channel of the barrel; the injection servo motor rotates to drive the ball The screw rotates, so that the ball screw nut drives the push plate to move linearly on the two parallel injection rods, and the plunger installed on the push plate can move linearly in the barrel at the same time, and finally completes the injection action; the injection servo motor is The linear reciprocating motion of the plunger can be realized by reversing; the hot runner nozzle is installed on the barrel through the nozzle gland, and its axis coincides with the axis of the melt channel of the barrel; the hot runner nozzle is heated by a heating wire or a heating ring, which is installed There are temperature sensors and pressure sensors; the mold clamping part is mainly composed of mold clamping servo motor, rear platen, moving platen, tie rod, ball screw, ball screw nut, coupling, clamping block seat, clamping screw and clamping block The base, the moving platen and the rear platen are connected in series through four pull rods in sequence, and a wear-resistant bushing is arranged between the moving platen and the pull rods; the mold clamping servo motor is fixed on the rear platen by screws, and its output shaft passes through A coupling is connected with the ball screw, and the ball screw nut is fixedly connected with the movable platen through screws, and the mold clamping servo motor drives the ball screw to rotate, so that the ball screw nut drives the movable platen and the mold to reciprocate on the four tie rods , and finally realize the mold opening and closing action; in the mold part, there is a corresponding stepped hole in the center of the fixed mold, which is compatible with the structure of the hot runner nozzle; the width of the ejector plate is slightly smaller than that of the movable mold, which is consistent with the structure of the movable template. 2. An all-electric miniature precision injection molding machine according to claim 1, characterized in that: the fixing device of the mold on the template is composed of a mold locking briquetting seat, a mold locking briquetting nozzle and a mold locking screw, and the mold locking briquetting nozzle The corresponding position of the front end and the mold has a slope structure, and the locking screw pushes the wedge-shaped mold pressing nozzle to press the mold against the slope to realize the installation of the mold. 3. An all-electric miniature precision injection molding machine according to claim 1, characterized in that: the form of the end screw is a single-entry Archimedes spiral or a multi-entry Archimedes spiral. 4. An all-electric miniature precision injection molding machine according to claim 1, characterized in that: the final ejection of the product depends on the moving platen retreating while the ball screw moves forward relatively when the mold is opened.

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