TWI395653B - Injection molding machine to correct the end of the injection method - Google Patents

Description

Method for correcting the exit end of the injection molding machine

The present invention relates to a method for correcting the exit end of an injection molding machine, and more particularly to a method for effectively controlling the amount of plastic residue in the injection hole to be within an allowable range to ensure the quality of the injection.

The vertical or horizontal injection molding machines currently used mainly include an organic table, a clamping unit, a driving assembly and an injection assembly. Wherein, the driving component and the shooting component are horizontally movable relative to the two rails. The injection assembly is provided with a material tube, and an injection shaft is coaxially accommodated in the material tube, and the injection shaft can be rotated and moved forward and backward by the oil pressure or the electric servo motor.

When the plastic is injection molded, the nozzle at the front end of the injection tube of the injection assembly is pressed against the gate of the mold of the clamp assembly, and the injection shaft is driven by the hydraulic motor or the electric servo motor to make the plastic in the material tube. The mixing is pushed forward, and the injection shaft is retracted by a reaction force for a certain distance, and then the plastic in the material tube is squeezed forward, so that the plastic in the material tube is injected into the mold of the clamping assembly at a high speed to make the plastic forming.

In the above injection molding process, since the injection of the plastic requires a high pressure, the injection bearing is relatively subjected to a large reaction force. Therefore, the injection shaft must have a high strength, but a high-strength, high-precision injection shaft is manufactured. Need a higher cost. The injection shaft is an elongated screw, and the plastic flows between the gums and the valleys, so that the plastic can flow smoothly during the process of extrusion and storage, and the diameter of the injection shaft cannot be too Small, as a result, it limits the size of the product to be shot, and it is not easy to shoot fine and tiny objects.

Therefore, the creator designed an injection molding machine a that can replace the injection assembly. As shown in Fig. 7, it mainly includes a machine a1. The upper end of the machine a1 is provided with a clamping module a2, a driving assembly a3, and a storage. The material assembly a4 and the injection assembly a5, wherein the clamping assembly a2 is fixed to the machine a1, and the driving assembly a3 and the storage assembly a4 are relatively moved with the clamping assembly a2. As shown in FIG. 8, the stock assembly a4 includes a material tube b. The material tube b is provided with a storage shaft b1 for use as a storage material, and one end of the material tube b extends at an angle. The outlet portion c is provided with a shot hole c1 that communicates with the shaft hole. The injection assembly a5 is detachably coupled to the projection c, and one end of the injection assembly a5 is provided with an injection axis d, and the injection axis d is accommodated in the injection hole d1 so as to be relatively linearly movable. The injection assembly a5 is connected to a power source e, so that after the storage shaft b1 pushes the plastic into the injection hole d1, the injection shaft is driven by the power source e, and the extruded plastic is injected into the clamp assembly a2.

Thereby, the problem of the conventional injection molding machine can be effectively improved. However, in the injection molding process, if the setting of the storage material is wrong, the plastic pushed into the injection hole is more than the plastic to be injected into the clamping assembly, and the injection shaft is squeezed. After the pressed plastic is injected into the clamping module, there is still residual plastic accumulated in the injection hole, and if the residual plastic is too much and remains in the injection hole, the plastic is easily deteriorated and the injection is caused. The decline in quality.

The problem of the above-mentioned residual plastic hoarding is also formed on the injection molding machine in which the injection shaft is coaxially accommodated in the material tube. Although the plastic is not deteriorated and the injection quality is not affected, when the injection molding machine is operated for a certain period of time and the operation is stopped, The plastic remaining on the front end of the tube will harden due to cooling. When another injection program is restarted and reheated, since the detector cannot accurately detect whether the residual plastic is completely melted, it is easy to start the injection operation when the interior of the residual plastic has not melted, thereby causing the injection shaft. The damage, or the quality of some products after injection.

In view of the above, in order to improve the above-mentioned shortcomings, the method of correcting the exit end of the injection molding machine can effectively control the amount of plastic residue in the injection hole within the allowable range to ensure the injection quality, and the inventors have accumulated many years of experience and continuous R&D improvements have resulted in the creation of the present invention.

The main object of the present invention is to provide a method for correcting the exit end of an injection molding machine. The detector detects the value of the actual exit end position of the injection axis, and then controls the injection axis to move backward through the comparison operation of the controller. The distance, so that the actual exit end position of the injection shaft can be controlled within a predetermined range, and most of the plastic can be injected in each injection process to reduce the residual amount of plastic, thereby ensuring the quality of the injected product. .

For the purpose of the above invention, the method for correcting the exit end of the injection molding machine of the present invention comprises the following steps: a. a setting step: providing a controller to set the value of the injection axis at the exit starting position and the predetermined injection The value of the end position; b. a detecting step: after the injection shaft shoots the plastic by an injection stroke to form an object, and then detects the value of the actual exit end position of the injection shaft by a detector; and c. Step: when the value of the actual injection end position of the injection axis is greater than the value of the predetermined injection end position, the controller corrects the distance moved after the injection axis, and in the next mode, the injection axis is again injected until the detection When the value of the actual exit end position of the injection axis detected by the device is less than or equal to the value of the predetermined exit end position, the corrective action of the controller is completed.

In implementation, the shooting action of the injection shaft can be directly emitted by setting the time, or by detecting the plastic pressure to determine the amount of injection, or by measuring the electronic position gauge to determine the control of the injection amount. Wherein, when the injection operation of the injection shaft is controlled by the measurement of the electronic position gauge to determine the injection amount, in the setting step, the controller simultaneously sets the value of the position of the filling phase to the pressure maintaining phase. In the correction step, the distance after the injection axis is moved backwards = the value of the injection path of the injection axis + the position of the predetermined injection end position, and the value of the actual injection end position of the injection axis.

In order to facilitate a more in-depth understanding of the present invention, it is described in detail later:

1‧‧‧Injection molding machine

2‧‧‧Storage components

21‧‧‧ material management

22‧‧‧Axis hole

23‧‧‧Storage shaft

24‧‧‧Adapter

25‧‧‧ shot hole

3‧‧‧Injecting components

31‧‧‧Inner shaft hole

32‧‧‧Piston

33‧‧‧ shot axis

4‧‧‧Hydraulic oil supply system

5‧‧‧ Controller

61‧‧‧ Shooting starting position

62‧‧‧ Scheduled end position

63‧‧‧ Shooting itinerary

631‧‧‧filling stage

632‧‧‧Pressure phase

64‧‧‧ Actual exit end position

65‧‧‧The distance from the axial movement

66‧‧‧ Filling stage to the stage of the holding pressure stage

7‧‧‧Detector

a‧‧‧Injection molding machine with replaceable injection assembly

A1‧‧‧ machine

A2‧‧‧clamp assembly

A3‧‧‧ drive components

A4‧‧‧Storage components

A5‧‧‧jecting components

B‧‧‧ material tube

B1‧‧‧ storage shaft

C‧‧‧protrusion

C1‧‧‧ shot hole

D‧‧‧ shot axis

D1‧‧‧ shot hole

e‧‧‧Power source

Figure 1 is a partial cross-sectional view of an injection molding machine to which the present invention is applied before injection.

Figure 2 is a partial cross-sectional view of an injection molding machine to which the present invention is applied after injection.

Figure 3 is a flow chart showing the steps of a preferred embodiment of the present invention.

Figure 4 is a schematic illustration of the steps of setting and detecting a preferred embodiment of the present invention.

Figure 5 is a schematic illustration of the modification steps of the preferred embodiment of the present invention.

Figure 6 is a schematic illustration of the preferred embodiment of the present invention with the injection stroke including a fill phase and a hold pressure phase.

Figure 7 is a side elevational view of an injection molding machine of a conventional replaceable injection assembly.

Figure 8 is a partial cross-sectional view of an injection molding machine of a conventional replaceable injection assembly.

Referring to Figures 1 and 2, there is shown an injection molding machine 1 in which the stocker assembly 2 and the injection unit 3 are disposed at an angle. The storage assembly 2 includes a material tube 21, and a shaft hole 22 is disposed in the material tube 21 for accommodating a spiral storage shaft 23 for use as a storage material, and one end of the material tube 21 is coupled to the material. The adapter 24 is provided with a shot hole 25 that communicates with the shaft hole 22. The injection assembly 3 is coupled to the adapter 24, and an inner shaft hole 31 is formed in the interior of the injection assembly 3 for the injection shaft 33 at one end of the piston 32 to pass through, and the push piston 32 via the hydraulic oil supply system 4 can be The injection shaft 33 is linearly reciprocated in the inner shaft hole 31. In implementation, the injection shaft 33 can also be driven by a servo motor. Thereby, when the stocker shaft 23 is rotated to push the plastic into the shot hole 25, the injection shaft 33 is driven by the hydraulic oil supply system 4 or the servo motor to inject the plastic into the mold. The hydraulic oil supply system 4 or the servo motor is controlled by a PLC programmable controller 5 to control the injection stroke of the injection shaft 33.

Referring to FIG. 3, a preferred embodiment of the method for correcting the exit end of the injection molding machine of the present invention comprises a setting step, a detecting step and a correcting step. As shown in Fig. 4, it is a schematic diagram of the above setting and detecting steps. The setting step is to set the value of the injection axis 33 at the exit start position 61 and the predetermined exit end position 62 by the controller 5; the detecting step is to advance the injection stroke 63 on the injection shaft 33 to project the plastic to form a shape. After the object, take a detector 7 The value of the exit position 33 of the injection axis 33 is detected. As shown in FIG. 5, the correction step is performed by the controller 5 when the value of the actual exit end position 64 of the exit shaft 33 is greater than the value of the predetermined exit end position 62. The distance 65 at which the injection shaft 33 moves backward is corrected, and in the corrected next mode, the injection shaft 33 is injected again or more until the actual injection end of the injection shaft 33 detected by the detector 7 is reached. When the value of the position 64 is less than or equal to the value of the predetermined exit end position 62, the correcting action of the controller 5 is completed.

In the implementation, the output shaft 33 in the setting step outputs the value of the starting point position 61 = the outputting stroke 63 of the injection axis + the actual injection end position 64 of the injection axis. The position 61 at which the exit axis 33 emits the starting point indicates that the plastic has been pressed into the inner shaft hole 31, but the injection shaft 33 has not yet been moved. The position of the actual exit end of the injection shaft 33 indicates that the injection shaft 33 is emitting. Move forward to the minimum position during the forming process. Each of the above-mentioned position points is measured by an electronic position scale, and the electronic position scale is used as the detector 7.

For example, the value of the predetermined exit end position set by the controller 5 for a certain product is 5 mm, the value of the exit position of the exit shaft 33 is 50 mm, and after the shot, the detector 7 measures the exit shaft 33. The value of the actual exit end position is 20 mm, and after the calculation by the controller 5, the injection stroke of the injection shaft 33 is 30 mm.

Since the value of the actual exit end position 64 of the exit shaft 33 is larger than the value of the predetermined exit end position 62, the correction is required by the controller 5. The correction formula is: the distance 65 after the injection axial movement is the value of the injection stroke 63 of the injection axis + the predetermined injection end position 62 - the value of the injection injection end position 64 of the injection axis. According to the above example, the injection stroke of the injection shaft 33 is 30 mm, the value of the predetermined exit end position is 5 mm, and the value of the actual exit end position of the injection shaft 33 is 20 mm. Therefore, the distance at which the injection shaft 33 moves backward = 30 + 5 - 20=15 (mm). That is, the distance that the injection shaft 33 corrected by the controller 5 moves backward is 15 mm. After the hydraulic oil supply system 4 or the servo motor is commanded by the controller 5, the drive injection shaft 33 is moved backward by 15 mm. At this time, the value of the exit shaft 33 of the injection shaft 33 measured by the detector 7 is 61. 35mm.

In the next mode, the injection shaft 33 is again injected at the corrected position. Since the injection stroke of the injection shaft 33 is 30 mm, the value of the actual injection end position 64 of the injection shaft 33 is 5 mm or less after another shot. 5mm, that is, the correcting action of the controller 5 is completed; however, if the value of the actual shooting end position 64 of the shooting shaft 33 is still greater than 5 mm, the controller 5 will perform another correction or multiple corrections until the detector 7 detects The value of the actual exit end position 64 of the exit shaft 33 is less than or equal to the value of the predetermined exit end position 62.

In the implementation, the injection shaft 33 performs an injection operation by the time set by the controller 5, and the injection shaft 33 can also detect the plastic pressure in the inner shaft hole 31 by the pressure detector, and then The controller 5 decides whether to continue shooting or by measuring the position of the electronic position gauge to decide whether to continue shooting.

As shown in FIG. 6, when the injection operation of the injection shaft 33 is controlled by the measurement of the electronic position gauge to determine the injection amount, since the injection stroke 63 includes a filling phase 631 and a pressure maintaining phase 632, Therefore, in the setting step, the controller 5 sets a value of the filling phase to the pressure maintaining phase position 66. In the correction step, the value of the filling phase transfer pressure stage position 66 is simultaneously corrected so that the injection shaft 33 maintains a fixed injection stroke 63.

In practice, the present invention can also be applied to an injection molding machine in which an injection shaft is coaxially accommodated in a material tube and stored and ejected by an injection shaft.

In this way, the present invention can be applied to various injection molding machines, and in each injection program, the actual injection end position 64 of the injection shaft 33 can be controlled within a certain range to emit most of the plastic. This effectively reduces the amount of plastic remaining in the inner shaft hole 31 and ensures the quality of the injected product.

In summary, according to the above disclosure, the present invention can achieve the intended purpose of the invention, and provide an injection molding machine capable of effectively controlling the amount of plastic residue in the injection hole to be within an allowable range to ensure the injection quality. The method of correcting the exit end point is very valuable for industrial use, and the invention patent application is filed according to law.

Figure 3 is a step flow chart

Claims (6)

A method for correcting an exit end of an injection molding machine, comprising: a. a setting step: providing a controller to set a value of an exit axis at an exit start position and a predetermined exit end position; b. a detecting step: After the injection shaft ejects the plastic by an injection stroke to form an object, the detector detects the value of the actual exit end position of the injection shaft; and c. a correction step: the value of the actual injection end position of the injection shaft is greater than When the value of the end position is scheduled to be output, the controller corrects the distance of the injection axis and then moves, and in the next mode, the injection axis is again injected until the detection axis detects the actual exit end position of the injection axis. When the value is less than or equal to the value of the predetermined exit end position, the corrective action of the controller is completed. A method of correcting an exit end of an injection molding machine as described in claim 1, wherein the controller is a PLC programmable controller. A method for correcting an exit end of an injection molding machine as described in claim 1, wherein the detector is an electronic position gauge. A method of correcting an exit end point of an injection molding machine according to the second or third aspect of the invention, wherein, in the setting step, the value of the exit axis exit start position = the exit stroke of the injection shaft + the actual exit end position of the injection shaft Value. The method of claiming the end point of the injection molding machine of claim 4, wherein the injection stroke comprises a filling phase and a holding phase; and in the setting step, the controller simultaneously sets a filling The value of the phase to the pressure holding phase position. The method of correcting the injection end point of the injection molding machine according to the first aspect of the invention, wherein, in the correcting step, the distance of the injection axis rearward movement = the injection path of the injection axis + the value of the predetermined injection end position - the injection The value at which the axis actually exits the end position.