Motion control system for injection table of injection molding machine

Abstract

The utility model relates to the technical field of injection molding machines, and discloses an injection table action control system of an injection molding machine, which comprises an oil tank used as a container, a power source used for providing high pressure, namely hydraulic pumps P1 and P2, and control elements, namely an electromagnetic reversing valve VA3, an electromagnetic reversing valve VC1, an electromagnetic reversing valve VC2, an electromagnetic reversing valve VC3, an electromagnetic reversing valve VC4, a proportional overflow valve VC5, and plug-in reversing valves VC6, VC7, VC8, VC9 and VC10. The glue injection oil cylinder and the glue melting motor are used as execution elements. An electromagnetic directional valve VA3 is arranged to be communicated with an oil tank, in the pressure relief process, pressure oil in a glue injection rod cavity can directly return to the oil tank through the electromagnetic directional valve VA3, and therefore the rapid pressure relief function is achieved, and the problems that an existing injection table hydraulic control system is slow in pressure relief, large pressure exists in a glue injection cavity when a glue injection valve is closed, and the pressure is too high are solved. And large vibration and abnormal sound can be caused.

Description

Technical Field

[0001] The utility model relates to the technical field of injection molding machines, in particular to a motion control system for a shooting platform of an injection molding machine. Background Art

[0002] An injection molding machine, also known as an injection molding machine, is a mechanical device used to manufacture plastic parts. Injection molding machines come in a variety of types and sizes to suit the production needs of different products. They are widely used to manufacture a variety of plastic products, such as automotive parts, household appliances, packaging materials, and toys. They heat and compress the plastic material to form it in a mold. The injection unit is the core component of the injection molding machine and consists of a plasticizing system and an injection system. The plasticizing system heats and plasticizes the plastic granules or powder into a molten state, while the injection system injects the molten plastic into the mold at high pressure.

[0003] The injection system's injection process primarily relies on a hydraulic system to control the feed and retraction motions. At the end of the injection process, the injection platform needs to retract. However, the existing injection platform hydraulic control system has a slow pressure relief mechanism. When the injection valve closes, high pressure remains in the injection chamber, causing significant vibration and abnormal noise. Utility Model Content

[0004] The technical problem solved by the utility model is that the existing hydraulic control system of the injection molding machine is slow to release pressure. When the injection valve is closed, there is a large pressure in the injection molding chamber, which will cause relatively large vibration and abnormal noise.

[0005] The purpose of the utility model can be achieved through the following technical solutions:

[0006] An injection molding machine shooting platform motion control system includes a fuel tank, a power source, an electromagnetic reversing valve VC2, an electromagnetic reversing valve VA3, an insert-type directional valve VC8, and an injection cylinder. The injection cylinder includes a rod chamber and a rodless chamber. One end of the power source is connected to the fuel tank, and the other end is connected to the electromagnetic reversing valve VC2 and the port 1 of the insert-type directional valve VC8 respectively. The end of the electromagnetic reversing valve VC2 away from the power source is connected to the port 2 of the insert-type directional valve VC8. The port 3 of the insert-type directional valve VC8 is connected to the rod chamber and one end of the electromagnetic reversing valve VA3 respectively. The other end of the electromagnetic reversing valve VA3 is connected to the fuel tank.

[0007] In one embodiment of the present invention, the power source includes two hydraulic pumps arranged in parallel.

[0008] In one embodiment of the present invention, a filter is provided between the hydraulic pump and the oil tank.

[0009] In one solution of the present invention, a pressure gauge is provided on the oil circuit between the hydraulic pump and the injection cylinder.

[0010] In one embodiment of the present invention, the plug-in directional valve VC8 is provided in parallel with a plug-in reversing valve VC6, a plug-in reversing valve VC7, and a plug-in reversing valve VC9. A one-way valve VC11 is provided between the rodless chamber of the injection cylinder and the oil tank. The plug-in reversing valve VC6 is a normally open plug-in reversing valve, and the plug-in reversing valves VC7, VC8, VC9, and VC10 are normally closed reversing valves. When the melt action is performed, the electromagnetic reversing valve VC3 is energized, the plug-in reversing valve VC9 is opened, and the oil in the rod chamber of the injection cylinder returns to the oil tank through the plug-in reversing valve VC9. At the same time, the oil in the return oil pipeline flows through the plug-in reversing valve VC6 and the one-way valve VC11 and enters the rodless chamber of the injection cylinder.

[0011] Beneficial effects of the utility model:

[0012] (1) A solenoid reversing valve VA3 is provided to connect to the oil tank. During the pressure relief process, the pressure oil in the injection rod cavity can be directly returned to the oil tank through the solenoid reversing valve VA3, thereby realizing the function of rapid pressure relief. This solves the problem that the existing hydraulic control system of the injection platform has slow pressure relief. When the injection valve is closed, there is a large pressure in the injection cavity, which will cause relatively large vibration and abnormal noise.

[0013] (2) When performing the melt action, the electromagnetic reversing valves VC4 and VC3 are energized, the plug-in reversing valve VC10 is opened, and the pressure oil enters the melt motor M3 through the plug-in reversing valve VC10, pushing the melt motor M3 to rotate and perform the melt action. At this time, since the electromagnetic reversing valve VC3 is also energized, the plug-in reversing valve VC9 is opened, and the oil in the rod chamber of the injection cylinder returns to the oil tank through the plug-in reversing valve VC9. At the same time, the rodless chamber of the injection cylinder also needs to absorb oil. At this time, the oil in the return oil pipeline flows through the plug-in reversing valve VC6 and the one-way valve VC11 and enters the rodless chamber of the injection cylinder, achieving rapid oil replenishment, preventing the problem of vacuum, solving the problem of inconsistent injection machine operation caused by cavity vacuum in the prior art, and ensuring the working efficiency of the injection molding machine.

[0014] Additional aspects and advantages of the present invention will be given in part in the following description and will become apparent from the following description or learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0016] Figure 1 It is a schematic structural diagram of the utility model as a whole;

[0017] Figure 2 It is a structural diagram of the injection oil circuit board part of the utility model.

[0018] The reference numerals in the figure are: 1, oil tank; 2, power source; 3, injection cylinder. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0021] In the description of this utility model, "several" means one or more, "many" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0022] See also Figure 1-2 The present invention is a control system for the injection molding machine's shooting platform. It includes an oil tank 1 serving as a reservoir, a power source 2 for providing high pressure: hydraulic pumps P1 and P2, and control elements: a solenoid directional valve VA3, a solenoid directional valve VC1, a solenoid directional valve VC2, a solenoid directional valve VC3, a solenoid directional valve VC4, a proportional relief valve VC5, and plug-in directional valves VC6, VC7, VC8, VC9, and VC10. Furthermore, an injection cylinder 3 and a melt motor serve as actuators. The injection cylinder 3 includes a rod chamber and a rodless chamber. One end of the power source 2 is connected to the oil tank 1, and the other end is connected to port 1 of the solenoid directional valve VC2 and plug-in directional valve VC8, respectively. The end of the solenoid directional valve VC2, remote from the power source 2, is connected to port 2 of the plug-in directional valve VC8. Port 3 of the plug-in directional valve VC8 is connected to the rod chamber and one end of the solenoid directional valve VA3, respectively. The other end of the solenoid directional valve VA3 is connected to the oil tank 1.

[0023] See also Figure 1-2In one embodiment of the present invention, a filter may be installed between the hydraulic pump and the oil tank 1 to remove impurities in the hydraulic oil (including mechanical impurities remaining in the system after cleaning, such as rust, casting sand, welding slag, etc., impurities entering the system from the outside, such as dust, and impurities generated during operation, such as debris and metal powder from seal wear) to prevent these impurities from damaging the system. A pressure gauge is installed in the oil circuit between the hydraulic pump and the injection cylinder 3 to effectively monitor the oil circuit pressure.

[0024] See also Figure 1-2 In one embodiment of the present utility model, the plug-in directional valve VC8 is provided in parallel with a plug-in reversing valve VC6, a plug-in reversing valve VC7, and a plug-in reversing valve VC9. A one-way valve VC11 is provided between the rodless chamber of the injection cylinder 3 and the oil tank 1. The plug-in reversing valve VC6 is a normally open plug-in reversing valve, and the plug-in reversing valves VC7, VC8, VC9, and VC10 are normally closed reversing valves. When the glue is melted, the solenoid reversing valve VC3 is energized, the plug-in reversing valve VC9 is opened, and the oil in the rod chamber of the injection cylinder 3 returns to the oil tank 1 through the plug-in reversing valve VC9. At the same time, the oil in the return oil pipeline flows through the plug-in reversing valve VC6 and the one-way valve VC11 and enters the rodless chamber of the injection cylinder 3.

[0025] The working principle of this utility model:

[0026] During injection, solenoid reversing valve VC2 is energized. At this point, P connects to B and A connects to T in solenoid reversing valve VC2, opening the plug-in reversing valve VC8. Pressurized oil flows through VC8 into the rod chamber of injection cylinder 3, pushing cylinder 3 forward and initiating injection. At the end of injection, solenoid reversing valve VA3 is energized. At this point, P connects to B and A connects to T in solenoid reversing valve VA3. The pressurized oil in the rod chamber is returned directly to tank 1 via solenoid reversing valve VA3, achieving rapid pressure relief. After pressure relief is complete, solenoid reversing valves VC2 and VA3 are de-energized, and injection ends. Because solenoid reversing valve VA3 is connected to tank 1, the pressurized oil in the rod chamber can be returned directly to tank 1 via solenoid reversing valve VA3 during the pressure relief process. This allows for rapid pressure relief, resolving the issue of slow pressure relief in existing injection platform hydraulic control systems. This leads to high pressure in the injection chamber when the injection valve is closed, causing significant vibration and noise.

[0027] During glue melting, the screw moves backward, meaning the injection cylinder 3 moves backward. At this point, the rodless chamber of the injection cylinder 3 needs to continuously absorb oil. If the oil absorption is not fast enough, after the glue melting operation is completed, the rodless chamber of the injection cylinder 3 needs to be filled with oil before the core-pulling operation can be performed. This will cause discontinuous shooting operations and reduce work efficiency. In existing injection control oil circuits, the plug-in reversing valve VC6 is typically a normally closed plug-in reversing valve. During this process, the rodless chamber needs to overcome the spring force of the plug-in reversing valve VC6 before it can absorb oil from the return oil line. As a result, the oil absorption efficiency is very low, and oil often fails to be absorbed. Because the rodless chamber of the injection cylinder 3 cannot be filled with oil in a timely manner, it is in a vacuum state. After the melting action is completed, when the glue extraction action is performed, the rodless cavity of the injection cylinder 3 needs to be filled with oil before the glue extraction action can be performed. This causes the injection machine to move incoherently. When the injection molding machine performs high-frequency continuous processing, the problem of the cavity vacuum limiting the retraction of the shooting platform will affect the efficiency and movement accuracy of the continuous processing, thereby affecting the work efficiency. In order to solve the above problems, in this application, the plug-in reversing valve VC6 is a normally open plug-in reversing valve, and the plug-in reversing valves VC7, VC8, VC9, and VC10 are normally closed reversing valves. The rodless cavity of the injection cylinder 3 is directly connected to the return oil pipeline. Specifically, when performing the melting action, the electromagnetic reversing valves VC4 and VC3 are energized, the plug-in reversing valve VC10 is opened, and the pressure oil enters the melting motor M3 through the plug-in reversing valve VC10, driving the melting motor M3 to rotate to perform the melting action. At this time, since the electromagnetic reversing valve VC3 is also energized, the plug-in reversing valve VC9 opens, and the oil in the rod chamber of the injection cylinder 3 returns to the oil tank 1 through the plug-in reversing valve VC9. At the same time, the rodless chamber of the injection cylinder 3 also needs to absorb oil. At this time, the oil in the return oil pipeline flows through the plug-in reversing valve VC6 and the one-way valve VC11 and enters the rodless chamber of the injection cylinder 3, realizing rapid oil replenishment, preventing vacuum problems, and ensuring the working efficiency of the injection molding machine.

[0028] The above describes an embodiment of the present invention in detail. However, the above description is only a preferred embodiment of the present invention and should not be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the claims of the present invention.

Claims

1. An injection molding machine shooting platform motion control system, characterized in that: The invention comprises an oil tank (1), a power source (2), an electromagnetic reversing valve VC2, an electromagnetic reversing valve VA3, an insert-type directional valve VC8 and a glue injection cylinder (3). The glue injection cylinder (3) comprises a rod chamber and a rodless chamber. One end of the power source (2) is connected to the oil tank (1), and the other end is connected to the electromagnetic reversing valve VC2 and the port 1 of the insert-type directional valve VC8 respectively. The end of the electromagnetic reversing valve VC2 away from the power source (2) is connected to the port 2 of the insert-type directional valve VC8. The port 3 of the insert-type directional valve VC8 is connected to the rod chamber and one end of the electromagnetic reversing valve VA3 respectively. The other end of the electromagnetic reversing valve VA3 is connected to the oil tank (1).

2. The injection molding machine shooting platform motion control system according to claim 1, characterized in that: The power source (2) comprises two hydraulic pumps arranged in parallel.

3. The injection molding machine shooting platform motion control system according to claim 2, characterized in that: A filter is provided between the hydraulic pump and the oil tank (1).

4. The injection molding machine shooting platform motion control system according to claim 2, characterized in that: A pressure gauge is provided on the oil circuit between the hydraulic pump and the injection cylinder (3).

5. The injection molding machine shooting platform motion control system according to claim 1, characterized in that: The invention also includes an insert-type reversing valve VC6, an insert-type reversing valve VC7, and an insert-type reversing valve VC9. A one-way valve VC11 is provided between the rodless chamber of the injection cylinder (3) and the oil tank (1). The insert-type reversing valve VC6 is a normally open insert-type reversing valve, and the insert-type reversing valves VC7, VC8, VC9, and VC10 are normally closed reversing valves. When performing the melt operation, the electromagnetic reversing valve VC3 is energized, the insert-type reversing valve VC9 is opened, and the oil in the rod chamber of the injection cylinder (3) returns to the oil tank (1) through the insert-type reversing valve VC9. At the same time, the oil in the return oil pipeline flows through the insert-type reversing valve VC6 and the one-way valve VC11 and enters the rodless chamber of the injection cylinder (3).

Images