Mold Shifting Control System and Two-Platen Injection Molding Machine

Abstract

The present invention discloses a moving mold control system and a two-platen injection molding machine, which relates to the technical field of injection molding equipment. The system includes a one-way main valve, a moving mold proportional valve, a moving mold oil cylinder assembly, an opening mold oil replenishing valve, and a controller. The A port of the one-way main valve is used to connect to the main pressure oil circuit of the injection molding machine, and the B port is connected to the P port of the moving mold proportional valve. The T port of the moving mold proportional valve is used to connect to the oil return tank of the injection molding machine, the A port is connected to the mold closing cavity in the moving mold oil cylinder assembly, and the B port is connected to the mold opening cavity in the moving mold oil cylinder assembly. The P port of the opening mold oil replenishing valve is connected to the B port of the one-way main valve, and the B port is connected to the mold opening cavity. The controller is used to control the energization of the moving mold proportional valve in the mold opening mode, and when the moving platen performs a deceleration operation in the mold opening mode, control the energization of the opening mold oil replenishing valve, so that the pressure oil in the main pressure oil circuit enters the mold opening cavity through the one-way main valve and the opening mold oil replenishing valve. This avoids the vacuum phenomenon in the mold opening cavity, thereby improving the smoothness of the mold opening movement of the moving platen.

Description

Technical Field

[0001] The present invention relates to the technical field of injection molding equipment, and particularly relates to a mold moving control system and a two-platen injection molding machine. Background Art

[0002] An injection molding machine is a main molding device that uses a plastic molding die to form various shaped plastic products from thermoplastic or thermosetting plastics. The working process of the injection molding machine involves mold closing and mold opening. The purpose of mold closing is to make the moving platen and the stationary platen closely close together to form a closed molding space; mold opening is generally the next step after mold closing, and the moving platen is separated from the stationary platen to facilitate the removal of the molded part.

[0003] When the moving platen needs to decelerate and brake during the mold opening operation, since the mold opening cavity of the two-platen injection molding machine is a rodless cavity and the mold closing cavity is a rod cavity, the braking force is completely provided by the mold closing cavity. However, the oil pressure area of the mold closing cavity is small and the braking force can only be provided by a high back pressure. At this time, it is necessary to reduce the opening of the mold moving proportional valve to provide the high back pressure. However, reducing the opening of the mold moving proportional valve will cause the mold opening cavity to not be refilled in time, which may cause a vacuum in the mold opening cavity. If a vacuum appears in the mold opening cavity, the moving platen will rebound and vibrate after the mold opening is in place, and the smoothness of the mold opening movement is poor. Summary of the Invention

[0004] To solve the technical problem of the poor smoothness of the mold opening movement of the moving platen in the two-platen injection molding machine in the above related technologies, the purpose of the present invention is to provide a mold moving control system and a two-platen injection molding machine.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The first aspect of the embodiment of the present invention provides a mold moving control system, including a one-way main valve, a mold moving proportional valve, a mold moving oil cylinder assembly, a mold opening oil replenishing valve, and a controller;

[0007] The A port of the one-way main valve is used to connect to the main pressure oil circuit of the injection molding machine, and the B port is connected to the P port of the mold moving proportional valve;

[0008] The T port of the mold moving proportional valve is used to connect to the oil return tank of the injection molding machine, the A port is connected to the mold closing cavity in the mold moving oil cylinder assembly, and the B port is connected to the mold opening cavity in the mold moving oil cylinder assembly;

[0009] The P port of the mold opening oil replenishing valve is connected to the B port of the one-way main valve, and the B port is connected to the mold opening cavity;

[0010] The controller is used to control the mold moving proportional valve to enter the mold opening mode in the mold opening mode. When the mold moving proportional valve is in the mold opening mode, the P port and the B port are communicated, and the A port and the T port are communicated;

[0011] The controller is further configured to control the mold opening oil replenishing valve to be energized when the moving platen performs a deceleration operation in the mold opening mode. The P port and the B port of the energized mold opening oil replenishing valve are communicated, so that the pressure oil in the main pressure oil circuit enters the mold opening cavity through the one-way main valve and the mold opening oil replenishing valve.

[0012] In an alternative embodiment, when the moving platen performs a deceleration operation in the mold opening mode, the controller is further configured to control the opening size of the moving mold proportional valve according to the current position of the moving platen and the maximum rated deceleration of mold opening.

[0013] In an alternative embodiment, the process by which the controller controls the opening size of the moving mold proportional valve according to the current position of the moving platen and the maximum rated deceleration of mold opening includes:

[0014] Calculating a mold opening calculated speed corresponding to the current position of the moving platen according to the current position of the moving platen and the maximum rated deceleration of mold opening;

[0015] Taking the smaller one of the mold opening calculated speed corresponding to the current position of the moving platen and the median of the mold opening set speed as the mold opening control speed;

[0016] Calculating a mold opening control voltage value corresponding to the current position of the moving platen based on the mold opening control speed through a pre-constructed linear function;

[0017] Controlling the opening size of the moving mold proportional valve according to the mold opening control voltage value.

[0018] In an alternative embodiment, the moving mold control system further includes:

[0019] A proportional pressure valve, connected between the B port of the one-way main valve and the oil return tank;

[0020] When the moving platen performs a deceleration operation in the mold opening mode, if the pressure in the mold opening cavity is higher than the conduction pressure of the proportional pressure valve, the pressure oil overflowing from the mold opening cavity flows back to the oil return tank through the proportional pressure valve.

[0021] In an alternative embodiment, the controller is further configured to increase the conduction pressure of the proportional pressure valve when the moving platen performs a deceleration operation in the mold opening mode and the distance between the moving platen and the set mold opening end position belongs to a first set distance range, so as to prevent the pressure oil overflowing from the mold opening cavity from flowing back to the oil return tank through the proportional pressure valve.

[0022] In an alternative embodiment, the controller is further configured to, when the moving platen reaches the set mold opening end position in the mold opening mode, control the A port, B port, P port, and T port of the mold moving proportional valve to be not connected to each other, and control the mold opening oil replenishing valve to be powered off.

[0023] In an alternative embodiment, the mold moving control system further includes:

[0024] A mold closing oil return assembly, connected between the T port of the mold moving proportional valve and the oil return tank, which includes a mold closing oil return valve and an oil return pilot valve; the A port of the mold closing oil return valve is connected to the T port of the mold moving proportional valve, and the B port is connected to the oil return tank; the P port of the oil return pilot valve is connected between the T port of the mold moving proportional valve and the A port of the mold closing oil return valve, the A port is connected to the pilot chamber of the mold closing oil return valve, and the T port is connected to the B port of the mold closing oil return valve;

[0025] And an express assembly, including an express valve and an express pilot valve, the A port of the express valve is connected between the T port of the mold moving proportional valve and the A port of the mold closing oil return valve, and the B port is connected to the mold opening chamber; the P port of the express pilot valve is connected to the mold opening chamber, the A port is connected to the pilot chamber of the express valve, and the T port is connected to the B port of the mold closing oil return valve;

[0026] The controller is further configured to, when the moving platen does not perform a deceleration operation in the mold opening mode, control the oil return pilot valve to be powered off, and control the express pilot valve to be powered on, so that the pressure oil flowing out of the mold closing chamber flows through the express valve to the mold opening chamber.

[0027] In an alternative embodiment, the controller is further configured to, when the moving platen does not perform a deceleration operation in the mold opening mode, control the mold opening oil replenishing valve to be powered on.

[0028] In an alternative embodiment, the controller is further configured to, when the moving platen does not perform a deceleration operation in the mold closing mode, control the oil return pilot valve and the express pilot valve to be powered on, so that the pressure oil flowing out of the mold opening chamber is diverted to the express valve and flows back to the oil return tank through the mold closing oil return valve.

[0029] In an alternative embodiment, the controller is further configured to, when the moving platen performs a deceleration operation in the mold closing mode, control the oil return pilot valve to be powered on and the express pilot valve to be powered off.

[0030] In an alternative embodiment, the mold moving control system further includes:

[0031] A one-way pilot valve is connected between the pilot chamber of the one-way main valve and the P port of the mold moving proportional valve; the P port of the one-way pilot valve is connected to the pilot chamber of the one-way main valve, the A port is used to be connected to the main pressure oil circuit, and the B port is connected between the B port of the one-way main valve and the P port of the mold moving proportional valve;

[0032] The controller is further configured to control the one-way pilot valve to be energized in the mold opening mode or the mold closing mode.

[0033] In a second aspect of the embodiments of the present invention, a two-platen injection molding machine is further provided, including the mold moving control system in any one of the first aspects provided above.

[0034] Compared with the prior art, the present invention has at least the following beneficial effects:

[0035] On the one hand, by configuring a one-way main valve in the main pressure oil circuit, when the pressure at the A port of the one-way main valve is greater than the pressure at the B port, the pressure oil can flow from the A port of the one-way main valve to the B port and flow into the mold moving proportional valve, enabling the normal operation of the mold opening mode or the mold closing mode; when the pressure oil supply to the mold moving control system is stopped, the pressure at the A port of the one-way main valve is less than the pressure at the B port, and the externally applied spring force in the pilot chamber of the one-way main valve will cause the valve core to close, preventing the pressure oil at the B port of the one-way main valve from flowing to the A port of the one-way main valve. This can not only ensure that the moving platen cannot rebound in the mold closing direction during the mold opening mode, but also ensure that the moving platen cannot rebound in the mold opening direction during the mold closing mode, and at the same time solve the problem of rebound during the mold closing of the spring mold; it can improve the movement smoothness of the moving platen;

[0036] On the other hand, when the moving platen performs a deceleration operation in the mold opening mode, the braking force is completely provided by the mold closing cavity. However, since the oil pressure area of the mold closing cavity is small, only high back pressure can provide the braking force. Therefore, to achieve the deceleration purpose, the opening of the mold moving proportional valve needs to be reduced to provide high back pressure, but reducing the opening of the mold moving proportional valve will cause the mold opening cavity to be unable to replenish oil in time, or even unable to intake oil effectively, which may lead to a vacuum in the mold opening cavity. Therefore, by additionally configuring another branch for replenishing oil to the mold opening cavity that does not rely on the pressure difference to supply oil - the branch where the mold opening replenishing oil valve is located, and controlling the mold opening replenishing oil valve to be energized when the moving platen performs a deceleration operation in the mold opening mode, the pressure oil in the main pressure oil circuit can enter the mold opening cavity without resistance through the one-way main valve and the mold opening replenishing oil valve. Thus, when the opening of the mold moving proportional valve is reduced, the pressure oil can still pass through the branch where the mold opening replenishing oil valve is located to properly replenish oil to the mold opening cavity, which can not only avoid the occurrence of a vacuum in the mold opening cavity, but also avoid affecting the deceleration braking effect, and ensure that the moving platen will not rebound or vibrate due to the vacuum in the mold opening cavity, greatly improving the smoothness of the mold opening movement. Description of the Drawings

[0037] Figure 1 Schematic structural diagram of a mold moving control system provided by the present invention;

[0038] Figure 2 Schematic structural diagram of another mold moving control system provided by the present invention;

[0039] Figure 3 Schematic structural diagram of yet another mold moving control system provided by the present invention.

[0040] Icon:

[0041] 1 - Main pressure oil circuit, 11 - One - way main valve, 111 - One - way pilot valve, 12 - Mold - opening oil - supplementing valve, 13 - Proportional pressure valve, 2 - Mold - moving proportional valve, 21 - Clamping control module, 22 - Mold - opening control module, 23 - Spool position detection module, 3 - First safety switch, 4 - Safety door, 5 - Second safety switch, 6 - Express valve, 61 - Express pilot valve, 7 - Clamping oil - return valve, 71 - Oil - return pilot valve, 8 - Oil - return tank, 9 - Mold - moving oil cylinder assembly, 91 - Mold - opening cavity, 92 - Clamping cavity, 93 - Mold - moving piston rod, 94 - Mold - moving position detection module, 95 - Pressure sensor. Detailed implementation manners

[0042] To facilitate the understanding of the present invention, the technical solutions and advantages of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. For the mechanisms or methods not elaborated in the present invention, reference can be made to the prior art. The specific structure and characteristics of the present invention will be described by way of examples below, which should not be construed as any limitation to the present invention. At the same time, for any one of the technical features mentioned (including implicitly or explicitly) below, and any one of the technical features directly shown or implicitly in the drawings, any combination or deletion can be continued among these technical features, thereby forming more other embodiments that may not be directly or indirectly mentioned in the present invention. The preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0043] Please refer to Figure 1 , Figure 1 Schematic structural diagram of a mold moving control system provided by the present invention. The mold moving control system provided by the present invention is applied to a two - plate injection molding machine and includes a one - way main valve 11, a mold - moving proportional valve 2, a mold - moving oil cylinder assembly 9, a mold - opening oil - supplementing valve 12, and a controller.

[0044] Port A of the one - way main valve 11 is used to connect to the main pressure oil circuit 1 of the injection molding machine, and port B is connected to port P of the mold - moving proportional valve 2.

[0045] The T port of the mold shifting proportional valve 2 is used to connect to the oil return tank 8 of the injection molding machine, the A port is connected to the mold closing cavity 92 in the mold shifting cylinder assembly 9, and the B port is connected to the mold opening cavity 91 in the mold shifting cylinder assembly 9.

[0046] The P port of the mold opening oil replenishing valve 12 is connected to the B port of the one-way main valve 11 , and the B port is connected to the mold opening cavity 91 .

[0047] The controller is used to control the mold shifting proportional valve 2 to enter the mold opening mode in the mold opening mode, and the P port of the mold shifting proportional valve 2 in the mold opening mode is connected to the B port, and the A port thereof is connected to the T port;

[0048] The controller is also used to control the mold opening oil replenishing valve 12 to be energized when the movable template performs a deceleration operation in the mold opening mode, and the P port of the mold opening oil replenishing valve 12 in the energized state is connected to the B port, so that the pressure oil of the main pressure oil circuit 1 passes through the one-way main valve 11 and the mold opening oil replenishing valve 12 and enters the mold opening cavity 91 without resistance.

[0049] Before applying the mold shifting control system provided by the present invention to the two-plate injection molding machine, the connection between the mold shifting control system and the main pressure oil circuit 1, the oil return tank 8, and the movable platen of the two-plate injection molding machine can be realized in accordance with the connection method described above, wherein the movable platen is connected to the mold shifting piston rod 93 in the mold shifting cylinder assembly 9, so that the mold shifting cylinder assembly 9 can drive the movable platen to perform mold opening or mold closing operations. Based on this, the above-mentioned mold opening mode can be understood as the working mode of the two-plate injection molding machine when the movable platen performs the mold opening operation. Similarly, the mold closing mode can be understood as the working mode of the two-plate injection molding machine when the movable platen performs the mold closing operation.

[0050] In addition, the controller included in the mold shifting control system provided by the present invention can be configured separately, or the controller provided by the injection molding machine can be reused.

[0051] The mold shifting control system provided by the present invention can be produced as a set with an injection molding machine during the production stage, or can be used as a separate product and applied to the injection molding machine after leaving the factory.

[0052] The following is an explanation of the technical principle of the mold shifting control system provided by the present invention to prevent the mold opening cavity 91 from having a vacuum:

[0053] In the mold opening mode, to ensure that the mold moving proportional valve 2 is in the mold opening working mode so that the pressure oil flows into the mold opening cavity 91 through the mold moving proportional valve 2, the controller can control the mold moving proportional valve 2 to enter the mold opening mode, so that the P port and the B port of the mold moving proportional valve 2 are connected, and its A port and the T port are connected. Based on this, when the pressure oil flowing into the A port of the one-way main valve 11 gradually increases and the pressure at the A port of the one-way main valve 11 is greater than the pressure in its pilot chamber, the spring at the A port will be pushed open, making the A port and the B port of the one-way main valve 11 connected. Therefore, the pressure oil will flow out from the A port to the B port of the one-way main valve 11, and successively flow through the P port and the B port of the mold moving proportional valve 2 to enter the mold opening cavity 91 of the mold moving oil cylinder assembly 9, and then flow out from the mold closing cavity 92 through the A port and the T port of the mold moving proportional valve 2 to the oil return tank 8. During this process, the pressure in the mold opening cavity 91 is greater than the pressure in the mold closing cavity 92. Therefore, the mold moving piston rod 93 arranged in the mold closing cavity moves in a direction away from the mold opening cavity 91, and further drives the moving template connected to the mold moving piston rod 93 to move in a direction away from the stationary template, realizing the mold opening operation.

[0054] During the process of performing the mold opening operation, to ensure that the moving template can be braked in time and stably at the set mold opening end position, after the moving template runs to a certain position, the controller will control the moving template to perform a deceleration operation. To achieve the purpose of deceleration, due to the structural configuration of the mold closing cavity 92 and the mold opening cavity 91, it is necessary to reduce the opening of the mold moving proportional valve 2 to reduce the pressure oil flowing into the mold opening cavity 91. However, when the opening of the mold moving proportional valve 2 decreases, it may cause insufficient oil to enter the mold opening cavity 91, and thus it is easy to cause a vacuum phenomenon in the mold opening cavity 91. Therefore, in this case, the controller controls the mold opening oil replenishing valve 12 to be energized, and the P port and the B port of the energized mold opening oil replenishing valve 12 are connected. In this way, even if the mold moving proportional valve 2 is unable to supply oil to the mold opening cavity 91, the pressure oil can still enter the mold opening cavity 91 from this branch without resistance of the mold opening oil replenishing valve 12. The so-called without resistance can be understood as that as long as the P port and the B port of the mold opening oil replenishing valve 12 are connected, the pressure oil can enter the mold opening cavity 91 through the mold opening oil replenishing valve 12, thus avoiding the vacuum in the mold opening cavity 91, realizing that the moving template will not rebound or vibrate due to the vacuum in the mold opening cavity 91, improving the smoothness of the mold opening movement, and also having no impact on the deceleration effect. On this basis, the controller can further reduce the pressure of the pressure oil in the main pressure oil circuit, so that the pressure of the pressure oil entering the mold opening cavity 91 through the mold opening oil replenishing valve 12 is also relatively low, which can better ensure that the pressure in the mold closing cavity 92 can counteract the pressure in the mold opening cavity 91, and further improve the deceleration braking effect and stability.

[0055] Therefore, the mold moving control system of the present invention can not only well avoid the vacuum in the mold opening cavity 91, improve the smoothness of the mold opening movement of the moving template, but also ensure the deceleration braking effect of the moving template. It can well improve the mold opening stability and reliability of the two-platen injection molding machine.

[0056] In order to better improve the stability of the moving template movement and ensure that the moving template can stop more timely and accurately at the set mold opening end position, in some embodiments, the mold moving control system of the present invention also provides a control scheme for the opening size of the mold moving proportional valve 2, that is, when the moving template performs a deceleration operation in the mold opening mode, the controller is further configured to control the opening size of the mold moving proportional valve 2 according to the current position of the moving template and the maximum mold opening rated deceleration, which may include:

[0057] In step S100, according to the current position of the moving template and the maximum mold opening rated deceleration, the mold opening calculated speed corresponding to the current position of the moving template is calculated;

[0058] In step S200, the smaller one of the mold opening calculated speed corresponding to the current position of the moving template and the median of the mold opening set speed is used as the mold opening control speed;

[0059] In step S300, based on the mold opening control speed, the mold opening control voltage value corresponding to the current position of the moving template is calculated through a pre-constructed linear function;

[0060] In step S400, the opening size of the mold moving proportional valve 2 is controlled according to the mold opening control voltage value.

[0061] To ensure the mold moving efficiency of the moving template and thus the output efficiency of the two-platen injection molding machine, the moving template can start decelerating and braking at a certain position, rather than requiring decelerating and braking operations at all positions during the entire mold moving process. Therefore, in the mold opening scenario, a deceleration section can be selected between the set mold opening start position and the set mold opening end position of the moving template. One end point of this deceleration section is between the mold opening start position and the mold opening end position, which can be selected according to actual requirements or experience, and the other end point is the mold opening end position. Thus, the mold opening deceleration position range can be obtained. Correspondingly, the distance between the mold opening start position and the starting point of the deceleration section corresponds to the non-deceleration section, which can also be called the mold opening non-deceleration position range.

[0062] Thus, when it is detected that the current position of the moving template is within the mold opening deceleration position range, it can be considered that the moving template is performing a deceleration operation. To ensure that the moving template can stop timely and accurately at the set mold moving end position, the above steps S100 to S400 can be executed.

[0063] Among them, the current position of the moving template can be detected by a mold moving position detection module. The mold moving position detection module can be arranged on the mold moving piston rod 93 in the mold moving oil cylinder assembly 9 of the two-platen injection molding machine. The mold moving position detection module can be connected to the controller to send the detected current position of the moving template to the controller.

[0064] As an example, the mold moving position detection module can be an electronic scale, but is not limited thereto.

[0065] During the execution of step S100, it can be calculated through the formula wherein, represents the mold opening calculation speed, represents the distance between the current position of the moving platen and the mold opening end position, represents the maximum rated deceleration of the moving platen during mold opening.

[0066] To obtain a higher accuracy of the maximum rated deceleration during mold opening, so as to further improve the control accuracy of the mold opening power flow, and further enable the moving platen to stop more reliably and in a timely manner at the mold opening end position. In some embodiments, the present invention further provides a solution for obtaining the maximum rated deceleration during mold opening: the maximum rated deceleration during mold opening is calculated based on the rated working pressure of the mold moving oil cylinder assembly 9 in the two-platen injection molding machine, the cylinder diameter of the mold moving oil cylinder assembly 9, the diameter of the mold moving piston rod 93 in the mold moving oil cylinder assembly 9, and the mass of the moving platen with the heaviest mold installed.

[0067] It can be understood that in order to obtain the maximum rated deceleration during mold opening, the controller of the two-platen injection molding machine can first obtain the following parameters:

[0068] The mass M of the moving platen with the heaviest mold installed, unit: kg; represents the mass of the machine clamping moving platen assembly in the two-platen injection molding machine when the heaviest mold allowed to be installed is included;

[0069] The rated working pressure of the mold moving oil cylinder assembly 9 , unit: Mpa;

[0070] The cylinder diameter of the mold moving oil cylinder assembly 9 , unit: mm;

[0071] The diameter of the mold moving piston rod 93 in the mold moving oil cylinder assembly 9 , unit: mm;

[0072] The maximum rated mold closing flow rate available for mold closing , unit: L / min;

[0073] The maximum rated mold opening flow rate available for mold opening , unit: L / min.

[0074] The above parameters can be read by the controller from the corresponding database or performance index storage space, but are not limited thereto. Among them, the acquisition of the maximum rated mold closing flow rate available for mold closing is considered for the mold closing mode and can be ignored in the mold opening mode.

[0075] Based on this, the maximum mold opening rated deceleration can be calculated by the following formula:

[0076]

[0077] The above formula can be obtained based on Newton's second law of motion and the relationship formula between force and pressure. The meanings of the letters in the formula can be seen in the relevant records above and will not be elaborated here. The unit of can be mm /

[0078] After calculating the mold opening calculation speed corresponding to the current position of the moving platen through step S100, the mold opening calculation speed corresponding to the current position can be compared with the mold opening set speed, where the mold opening set speed is user-defined, indicating the speed at which the user hopes the moving platen performs the mold opening operation at certain positions or position intervals.

[0079] If the comparison result indicates that the mold opening calculation speed corresponding to the current position of the moving platen is less than or equal to the mold opening set speed corresponding to the current position, it means that the mold opening set speed has exceeded the maximum speed that can ensure the reliable and stable braking of the moving platen at the mold opening end position. Therefore, to ensure the stable and accurate braking of the moving platen, the mold opening control will be based on the mold opening calculation speed at this time, rather than the mold opening set speed set by the user.

[0080] On the contrary, if the comparison result indicates that the mold opening calculation speed corresponding to the current position of the moving platen is greater than the mold opening set speed corresponding to the current position, it means that the mold opening set speed has not exceeded the maximum speed that can ensure the reliable and stable braking of the moving platen at the mold opening end position. Therefore, to ensure the user experience, the mold opening control can be based on the user's needs first at this time.

[0081] Therefore, in step S200, the smaller one of the mold opening calculation speed and the mold opening set speed corresponding to the current position of the moving platen is taken as the mold opening control speed. If the mold opening calculation speed and the mold opening set speed are equal, the mold opening calculation speed is taken as the mold opening control speed.

[0082] Next, step S300 can be executed to calculate the mold opening control voltage value corresponding to the current position of the moving platen based on the mold opening control speed through a pre-constructed linear function.

[0083] For example, assume the linear function , where and are both coefficients of the function and are known values, is the mold opening speed, Represents the mold opening control voltage. Based on this, during the execution of step S300, the mold opening calculation speed can be substituted into . At this time, the value of is the corresponding mold opening control voltage value.

[0084] In some embodiments, the present invention also provides a construction scheme for the corresponding linear function. The construction process of this linear function includes:

[0085] In step S011, according to the maximum rated mold opening flow rate of the two-platen injection molding machine and the diameter of the moving mold piston rod 93, the maximum rated mold opening speed of the moving platen is obtained;

[0086] In step S012, with the mold opening speed as the independent variable and the mold opening control voltage as the dependent variable, according to the maximum rated mold opening speed and its corresponding maximum mold opening control voltage, as well as the minimum mold opening speed and its corresponding minimum mold opening control voltage, the mold opening linear function is constructed; wherein, the minimum mold opening speed is 0.

[0087] It can be understood that before executing steps S100 to S400 of the present invention, or before executing step S300, the mold opening linear function can be constructed first through steps S011 to S012.

[0088] During the execution of step S011, the maximum rated mold opening speed can be calculated through the following formula:

[0089]

[0090] The above formula can be obtained based on the relationship formula between flow rate and speed. After calculation through the above formula, the unit of can be converted to mm / s, that is, in the formula, is the maximum rated mold opening speed, and the unit is: mm / s. The meanings of other letters can be seen in the relevant records above and will not be elaborated here.

[0091] After obtaining the maximum rated mold opening speed, step S012 can be executed. With the mold opening speed as the independent variable and the mold opening control voltage as the dependent variable, and based on two coordinate points: and , the mold opening linear function can be constructed based on relevant mathematical principles. Among them, represents the maximum mold opening control voltage, represents the minimum mold opening control voltage.

[0092] For example, assume that in the case of mold opening operation, the maximum mold opening control voltage that the moving mold proportional valve 2 can reach is -10V. Based on this maximum mold opening control voltage It can make the opening speed of the moving template reach the maximum rated opening speed Therefore, coordinate points can be obtained . And assume that the minimum opening control voltage that the moving mold proportional valve 2 can reach is -1.3V. Based on this minimum opening control voltage , it can make the opening speed of the moving template reach 0. Therefore, coordinate points ([[]] ) can be obtained.

[0093] It should be understood that the magnitude of the above voltage does not depend on the preceding "+" and "-" signs, but on the magnitude of the value following the sign. The signs are only for distinguishing the control voltage of the mold closing operation and the control voltage of the mold opening operation.

[0094] Based on this, the linear function in the mold opening mode can be: . In this case, it can be seen that in the above formula , , .

[0095] Thus, by calling the linear function, the opening control voltage value corresponding to the current position of the moving template can be calculated based on the opening control speed.

[0096] Next, step S400 can be executed to control the opening size of the moving mold proportional valve 2 by using the opening control voltage value calculated through step S300.

[0097] Based on the same principle, during the deceleration operation of the moving template in the mold closing mode, the opening size of the moving mold proportional valve 2 can also be controlled according to the above control principle. The difference is that the calculation methods of the maximum rated mold closing deceleration and the maximum rated mold closing speed in the mold closing mode are respectively adjusted to:

[0098]

[0099] Among them, represents the maximum rated mold closing deceleration, and its unit is also mm / . is the maximum rated mold closing speed, and the unit is: mm / s. The meanings of other letters can be seen in the relevant records above and will not be elaborated here.

[0100] In addition, due to the above-mentioned acquisition schemes for the non-deceleration position range and deceleration position range of mold opening, which do not consider the motion performance of the machine itself but are user-defined, it is easy to result in an excessive or insufficient distance in the finally obtained deceleration position range of mold opening. An excessive distance may lead to an increase in the mold moving time of the moving platen, which is not conducive to improving production efficiency, while an insufficient distance may cause the moving platen to not have sufficient deceleration distance to stop. Therefore, to solve these technical problems, in some embodiments, the present invention also provides another acquisition scheme for the non-deceleration position range and deceleration position range of mold opening, that is, the controller is further configured to acquire the non-deceleration position range of the moving platen in the mold opening mode, including:

[0101] In step Sa1, according to the maximum rated mold opening speed of the moving platen and the maximum rated mold opening deceleration, determine the minimum deceleration distance required for the moving platen to decelerate from the maximum rated mold opening speed to zero;

[0102] In step Sa2, according to the minimum deceleration distance and the set deceleration distance coefficient, determine the target deceleration distance of the moving platen;

[0103] In step Sa3, according to the set mold opening start position of the moving platen and the target deceleration distance, determine the non-deceleration position range of mold opening.

[0104] Thus, before executing steps S100 to S400, the non-deceleration position range of mold opening can be obtained through steps Sa1 to Sa3.

[0105] During the execution of step Sa1, the minimum deceleration distance can be calculated through the formula where, represents the minimum deceleration distance, with the unit of: mm, represents the maximum rated mold opening speed, correspondingly, represents the square of the maximum rated mold opening speed, represents the maximum rated mold opening deceleration.

[0106] Subsequently, during the execution of step Sa2, the target deceleration distance can be calculated through the formula where, is the preset deceleration distance coefficient in the mold opening mode, which can be user-defined or can adopt the system default value.

[0107] After obtaining the target deceleration distance, step Sa3 can be executed. Taking the mold opening start position as zero, then the position range corresponding to [mold opening start position, mold opening end position target deceleration distance) can be used as the non-deceleration position range of mold opening.

[0108] Correspondingly, the position range corresponding to [the mold opening end position the target deceleration distance, the mold opening end position] is used as the mold opening deceleration position range.

[0109] Thus, by incorporating the motion performance of the moving platen, the mold opening non-deceleration position range and the mold opening deceleration position range can be obtained, which can better ensure that the moving platen stops in time and accurately at the mold moving end position, and can better ensure the motion stability of the moving platen. On this basis, combined with the control scheme of steps S100 to S400, a better braking technical effect can be achieved - the moving platen is locked in time and accurately at the set mold opening end position.

[0110] Based on the same technical principle, the mold closing non-deceleration position range and the mold closing deceleration position range in the mold closing mode can also be obtained.

[0111] In some embodiments, to ensure that the position of the moving platen has the same standard in the mold closing operation and the mold opening operation, and thus better ensure the operation effect of the moving platen, the mold closing end position corresponding to the moving platen in the mold closing operation is the same as the mold opening start position corresponding to the moving platen in the mold opening operation, both being the zero position. And, the mold closing start position corresponding to the moving platen in the mold closing operation is the same as the mold opening end position corresponding to the moving platen in the mold opening operation.

[0112] Based on the embodiments shown in steps Sa1 to Sa3, to ensure that the obtained mold opening deceleration position range can more reliably ensure that the moving platen stops in time and accurately at the mold opening end position, in some embodiments, the present invention also provides another scheme for obtaining the mold opening deceleration position range, that is, the controller is further configured to obtain the mold opening deceleration position range of the moving platen in the mold opening mode, including:

[0113] In step Sb1, according to the maximum set mold opening speed of the moving platen within the mold opening deceleration position range and the maximum mold opening rated deceleration of the moving platen, the actual deceleration distance required by the moving platen is obtained;

[0114] In step Sb2, according to the actual deceleration distance and the set mold opening end position, the mold opening deceleration position range corresponding to the moving platen is determined.

[0115] After executing step Sa3, steps Sb1 to Sb2 can be executed. During the execution of step Sb1, first obtain the maximum set mold opening speed within the mold opening non-deceleration position range, and then through the formula calculate the actual deceleration distance required at the maximum set mold opening speed, where represents the maximum set mold opening speed of the moving platen within the mold opening non-deceleration position range, and the meanings of other letters are as described in the relevant records above. Among them, in the case where is not set, in the formula It can be deleted.

[0116] After obtaining the actual deceleration distance required for the moving template through step Sb1, step Sb2 can be executed to determine the opening die deceleration position range corresponding to the moving template according to the actual deceleration distance and the set opening die end position. For example, the position range corresponding to [opening die end position actual deceleration distance, opening die end position] is used as the opening die deceleration position range.

[0117] Since the maximum set opening die speed of the moving template is user-defined and the moving template will not run at a speed exceeding the maximum set opening die speed, by dividing the position of the moving template during the opening die process into an opening die non-deceleration position range and an opening die deceleration position range, and the opening die deceleration position range is determined according to the maximum set opening die speed of the moving template in the opening die non-deceleration section and the maximum opening die rated deceleration of the moving template, it can ensure that the opening die deceleration position range better meets the distance requirement for the moving template to accurately and reliably decelerate to the opening die end position. On this basis, after the moving template enters the deceleration section, the corresponding opening die calculation speed is calculated in real time according to the current position of the moving template and the maximum opening die rated deceleration, and the opening die calculation speed obtained each time is compared with the corresponding opening die set speed, and the smallest value is selected to control the opening die corresponding to the current position of the moving template, which can ensure that during the operation of the moving template in the deceleration section, no matter which position it runs to, it can finally be braked in time at the set opening die end position. Thus, through the combination of the above two technical levels, it can be better realized to lock the moving template in time and accurately at the opening die end position. The same technical effect can also be achieved by adopting the same technical solution in the closing die operation.

[0118] In some embodiments, to further improve the opening die braking effect and save energy, the controller can also be used to control the opening die flow rate of the main pressure oil circuit 1 in the two-platen injection molding machine according to the opening die control speed.

[0119] Thus, by using the opening die control speed to control both the opening of the moving die proportional valve 2 and the opening die flow rate of the main pressure oil circuit 1, not only can the opening die braking effect be improved by combining the two, but also the fuel consumption in the oil circuit can be saved and energy waste can be avoided.

[0120] In some examples, the mapping relationship table between the moving die speed and the moving die flow rate can be constructed in advance according to the correlation relationship between the moving die speed and the moving die flow rate of the main oil circuit. Thus, the mapping relationship table can be called to obtain the opening die flow rate corresponding to the current opening die control speed, and based on this opening die flow rate, the opening size of the valve between the main pressure oil circuit 1 and the oil supply tank can be controlled, or the rotation speed of the servo motor for driving the pressure oil supply can be controlled.

[0121] Similarly, the controller can also be used to control the mold - closing flow rate of the main pressure oil circuit 1 in the two - plate injection molding machine according to the mold - closing control speed.

[0122] In some other examples, to reduce the data storage amount and improve the determination efficiency and accuracy of the moving - mold flow rate, the controller controls the opening - mold flow rate of the main pressure oil circuit 1 in the two - plate injection molding machine according to the opening - mold control speed, which may include: obtaining the corresponding opening - mold flow rate according to the opening - mold control speed and the diameter of the moving - mold piston rod 93 in the moving - mold oil cylinder assembly 9.

[0123] Similarly, the controller controls the mold - closing flow rate of the main pressure oil circuit 1 in the two - plate injection molding machine according to the mold - closing control speed, which may include: obtaining the corresponding mold - closing flow rate according to the mold - closing control speed, the cylinder diameter of the moving - mold oil cylinder assembly 9, and the diameter of the moving - mold piston rod 93 in the moving - mold oil cylinder assembly 9.

[0124] Based on this, the mold - closing flow rate corresponding to the moving platen at the current position and the opening - mold flow rate can be calculated respectively through the following formulas:

[0125]

[0126]

[0127] In the above formulas, the unit of the mold - closing flow rate and the opening - mold flow rate corresponding to the moving platen at the current position is L / min. represents the mold - closing control speed corresponding to the moving platen at the current position, represents the opening - mold control speed corresponding to the moving platen at the current position, and the meanings of other letters can be referred to the relevant records above.

[0128] In some embodiments, to further improve the opening - mold movement stability of the moving platen, please refer to Figure 2 , Figure 2 which is a schematic structural diagram of another moving - mold control system provided by the present invention. The moving - mold control system of the present invention may further include:

[0129] A proportional pressure valve 13, connected between port B of the one - way main valve 11 and the oil return tank 8;

[0130] In the case where the moving platen performs a deceleration operation in the opening - mold mode, if the pressure in the opening - mold cavity 91 is higher than that of the proportional pressure valve 13, the pressure oil overflowing from the opening - mold cavity 91 flows back to the oil return tank 8 through the proportional pressure valve 13.

[0131] Thus, when the moving template performs a deceleration operation in the mold opening mode, the main pressure oil can be made to supply pressure oil to the mold opening cavity 91 at the conduction pressure, thereby achieving control over the amount of pressure oil entering the mold opening cavity 91 and avoiding affecting the deceleration effect. Moreover, during the deceleration process, if the pressure in the mold opening cavity 91 is higher than the conduction pressure of the proportional pressure valve 13, the pressure oil in the mold opening cavity 91 can overflow to the oil return tank 8 through the moving mold proportional valve 2 and the proportional pressure valve 13, preventing the power requirement of the servo motor from constantly changing due to changes in the pressure in the mold opening cavity 91, so as to ensure that the servo motor can output pressure oil with a stable oil volume at a stable servo power, and achieving the speed stability of the moving template during the mold opening deceleration process.

[0132] In some embodiments, to ensure the motion stability of the moving template during the process of approaching the mold opening end position, the controller is further configured to increase the conduction pressure of the proportional pressure valve 13 when the moving template performs a deceleration operation in the mold opening mode and the distance between the moving template and the set mold opening end position falls within a first set distance range, so as to prevent the pressure oil overflowing from the mold opening cavity 91 from flowing back to the oil return tank 8 through the proportional pressure valve 13.

[0133] In the above, the first set distance range can be set according to experience or actual requirements, and the present invention does not limit this. Since the opening of the moving mold proportional valve 2 may be smaller during the process of the moving template approaching the mold opening end position, by increasing the conduction pressure of the proportional pressure valve 13 to prevent the pressure oil overflowing from the mold opening cavity 91 from flowing back to the oil return tank 8 through the proportional pressure valve 13, it is possible to ensure that the mold opening cavity 91 maintains a relatively stable pressure, avoiding affecting the pressure balance between the mold opening cavity 91 and the mold closing cavity 92 due to the overflow of pressure oil, and thereby effectively ensuring the stability of the moving template when braking.

[0134] In some embodiments, to ensure that the moving template brakes stably at the mold opening end position, the controller is further configured to control the A port, B port, P port, and T port of the moving mold proportional valve 2 to be non - communicating and control the mold opening oil replenishing valve 12 to be powered off when the moving template reaches the set mold opening end position in the mold opening mode.

[0135] Thereby, the supply of pressure oil to the mold opening cavity 91 and the mold closing cavity 92 can be cut off, further ensuring that the moving template does not continue to move when it reaches the mold opening end position. In addition, the conduction voltage of the proportional pressure valve 13 can be set to 0, but is not limited thereto.

[0136] In some embodiments, to enable the moving template to perform a faster mold opening to improve the production efficiency of the injection molding machine, please refer to Figure 3 , Figure 3 which is a schematic structural diagram of another moving mold control system provided by the present invention. The moving mold control system of the present invention may further include:

[0137] The mold closing oil return assembly is connected between the T port of the mold shifting proportional valve 2 and the oil return tank 8, and includes a mold closing oil return valve 7 and an oil return pilot valve 71; the A port of the mold closing oil return valve 7 is connected to the T port of the mold shifting proportional valve 2, and the B port is connected to the oil return tank 8; the P port of the oil return pilot valve 71 is connected between the T port of the mold shifting proportional valve 2 and the A port of the mold closing oil return valve 7, the A port is connected to the pilot cavity of the mold closing oil return valve 7, and the T port is connected to the B port of the mold closing oil return valve 7.

[0138] And an express component, including an express valve 6 and an express pilot valve 61, wherein the A port of the express valve 6 is connected between the T port of the mold shifting proportional valve 2 and the A port of the mold closing oil return valve 7, and the B port is connected to the mold opening cavity 91; the P port of the express pilot valve 61 is connected to the mold opening cavity 91, the A port is connected to the pilot cavity of the express valve 6, and the T port is connected to the B port of the mold closing oil return valve 7.

[0139] The controller is also used to control the oil return pilot valve 71 to be powered off and control the express pilot valve 61 to be powered on when the movable template does not perform a deceleration operation in the mold opening mode, so that the pressure oil flowing out of the mold closing cavity 92 flows to the mold opening cavity 91 through the express valve 6.

[0140] Therefore, when the movable template does not perform the deceleration operation in the mold opening mode, that is, when the current position of the movable template is in the mold opening non-deceleration position range, in order to ensure that the movable template can run at high speed, by adding a mold closing oil return component and an express component, and controlling the power off of the return oil pilot valve 71 in the mold closing oil return component and the power on of the express pilot valve 61 in the express component, it is achieved that even when the pressure at port A of the mold closing oil return valve 7 is greater than the pressure at port B, due to the connection between the pilot chamber of the mold closing oil return valve 7 and the A and P ports of the return oil pilot valve 71, and the pressure of the spring in the pilot chamber of the mold closing oil return valve 7, the A and B ports of the mold closing oil return valve 7 cannot be connected, and therefore the passage between the pressure oil flowing out of the T port of the mold shifting proportional valve 2 and the return oil tank 8 is disconnected. The express pilot valve 61 is conductive, so that when the pressure at port A of the express valve 6 is greater than the pressure at port B, ports A and B of the express valve 6 can be connected, so that the pressure oil flowing out of port T of the mold shifting proportional valve 2 can flow out of port B through port A of the express valve 6 to enter the mold opening cavity 91, thereby quickly replenishing oil to the mold opening cavity 91 and realizing differential express mold opening.

[0141] In some embodiments, in order to extend the service life of the mold shifting proportional valve 2, the controller is also used to control the mold opening oil replenishing valve 12 to be energized when the movable platen does not perform a deceleration operation in the mold opening mode.

[0142] That is to say, in the mold opening mode, the mold opening oil replenishing valve 12 can be continuously controlled to be energized. After the mold opening oil replenishing valve 12 is energized, it can provide another oil path branch for the pressure oil flowing out from the B port of the one-way main valve 11 to enter the mold opening cavity 91. That is, the pressure oil flowing out from the main pressure oil path 1 can enter the mold opening cavity 91 through the moving mold proportional valve 2 and the mold opening oil replenishing valve 12 respectively. It can be seen that the mold opening oil replenishing valve 12 plays a role in splitting the pressure oil, which can reduce the oil inlet flow rate of the moving mold proportional valve 2, and thus can effectively reduce the energy consumption and spool heating of the moving mold proportional valve 2, which is beneficial to extending the service life of the moving mold proportional valve 2. Combining this solution with the solution of the previous embodiment can further improve the mold opening speed.

[0143] Since the mold opening cavity 91 is a rodless cavity and the mold clamping cavity 92 is a rod cavity, at the same moving mold speed, the pressure oil flow rate in the mold opening cavity 91 is much larger than that in the mold clamping cavity 92. In this way, when the moving template does not perform a deceleration operation in the mold clamping mode, since the opening of the moving mold proportional valve 2 is usually relatively large to ensure the mold clamping speed in the non-deceleration section, the pressure oil flow rate flowing into the mold clamping cavity 92 is also relatively large. Correspondingly, the pressure oil flow rate flowing out from the mold opening cavity 91 is even larger. If all this pressure oil flows out from the moving mold proportional valve 2, it will inevitably cause more energy consumption in the moving mold proportional valve 2, and the spool is also prone to heating, and it may also affect the mold clamping speed. Therefore, to solve these technical problems, in some embodiments, the controller is further configured to control the oil return pilot valve 71 and the express pilot valve 61 to be energized when the moving template does not perform a deceleration operation in the mold clamping mode, so that the pressure oil flowing out from the mold opening cavity 91 is split to the express valve 6 and flows back to the oil return tank 8 through the mold clamping oil return valve 7.

[0144] In the mold clamping mode, the controller will control the moving mold proportional valve 2 to enter the mold clamping working mode, and the mold opening oil replenishing valve 12 is in the power-off state, so that the P port and the A port of the moving mold proportional valve 2 are connected, and the B port and the T port are connected, so as to realize that the pressure oil of the main pressure oil path 1 flows into the mold clamping cavity 92 from the moving mold proportional valve 2, and no pressure oil flows into the mold opening cavity 91, so as to ensure that the moving template can accurately perform the mold clamping operation.

[0145] During the process when the moving template is in the mold clamping mode and does not perform a deceleration operation, to avoid excessive oil output of the moving mold proportional valve 2 causing spool heating, excessive energy consumption, and affecting the mold clamping speed of the moving template, the controller controls the oil return pilot valve 71 and the express pilot valve 61 to be energized. In this way, a part of the pressure oil flowing out from the mold opening cavity 91 will be split to the express valve 6, that is, it flows from the B port of the express valve 6 to the A port of the express valve 6, and flows out from the A port of the mold clamping oil return valve 7 to the B port of the mold clamping oil return valve 7, and then flows into the oil return tank 8 through the B port of the mold clamping oil return valve 7.

[0146] Thus, by diverting the pressure oil flowing out of the mold opening cavity 91, the flow rate of the pressure oil flowing out of the mold moving proportional valve 2 can be reduced, thereby effectively reducing the energy consumption and the heating of the valve core of the mold moving proportional valve 2, which is beneficial to extending the service life of the mold moving proportional valve 2. At the same time, the mold closing speed and the stability of the mold closing movement of the moving platen can be ensured.

[0147] In the case where the moving platen performs a deceleration operation in the mold closing mode, since the opening of the mold moving proportional valve 2 will decrease and the flow rate of the pressure oil passing through will also decrease, it is not necessary to continue to control the energization of the express pilot valve 61, so as to save energy to a certain extent. Based on this, in some embodiments, the controller is further configured to control the oil return pilot valve 71 to be energized and the express pilot valve 61 to be de-energized when the moving platen performs a deceleration operation in the mold closing mode.

[0148] That is to say, in the mold closing mode, the oil return pilot valve 71 can always be in the energized state. Among them, during the process when the moving platen does not perform a deceleration operation, the express pilot valve 61 can also be controlled to be energized, and during the process when the moving platen performs a deceleration operation, the express pilot valve 61 can be controlled to be de-energized. Thus, during the process when the moving platen performs a deceleration operation, the oil flowing out of the mold opening cavity 91 can only flow from port B to port T of the mold moving proportional valve 2, and then flows out to the oil return tank 8 through port A and port B of the mold closing oil return valve 7.

[0149] In some embodiments, to further ensure the stable progress of the mold closing mode or the mold opening mode, and to avoid the pressure oil flowing into the mold closing cavity 92 or the mold opening cavity 91 at will due to the pressure at port A of the one-way main valve 11 being greater than the pressure at port B of the one-way main valve 11 in an injection molding machine that does not require mold closing and mold opening operations, which affects the reliability of the injection molding machine, please continue to refer to Figure 3 , the mold moving control system provided by the present invention may further include:

[0150] A one-way pilot valve 111, connected between the pilot cavity of the one-way main valve 11 and port P of the mold moving proportional valve 2; port P of the one-way pilot valve 111 is connected to the pilot cavity of the one-way main valve 11, port A is used to be connected to the main pressure oil circuit 1, and port B is connected between port B of the one-way main valve 11 and port P of the mold moving proportional valve 2;

[0151] The controller is further configured to control the one-way pilot valve 111 to be energized in the mold opening mode or the mold closing mode.

[0152] Therefore, when it is necessary to control the moving platen to perform the mold closing operation or the mold opening operation, the one-way pilot valve 111 is controlled to be energized. In this way, when the pressure at port A of the one-way main valve 11 is greater than the pressure at port B of the one-way main valve 11, ports A and B of the one-way main valve 11 can be connected, and the pressure oil in the main pressure oil circuit 1 can enter the mold moving proportional valve 2. This can ensure the reliability and use safety of the injection molding machine.

[0153] When it is not necessary for the moving platen to perform the mold closing operation and the mold opening operation, the controller controls the one-way pilot valve 111 to be de-energized. In this case, port A and port P in the one-way pilot valve 111 are connected, the P port of the one-way pilot valve 111 is connected to the pilot chamber of the one-way main valve 11, and port A of the one-way pilot valve 111 and port A of the one-way main valve 11 are also both connected to the main pressure oil circuit 1. Therefore, the pressure in the pilot chamber of the one-way main valve 11 is the same as the pressure at port A of the one-way main valve 11. Coupled with the pressure action of the spring in the pilot chamber, the closed state of port A will be maintained. Therefore, ports A and B of the one-way main valve 11 cannot be connected, so that when the injection molding machine is not in the mold closing mode and the mold opening mode, the pressure oil will not flow into the mold moving proportional valve 2, and the moving platen will not be caused to perform the mold moving operation, ensuring the safety of the injection molding machine after standby or shutdown.

[0154] For safety considerations, in some embodiments, please refer to Figure 3 , the mold moving control system provided by the present invention may further include:

[0155] A first safety switch 3 for detecting the opening and closing state of the safety door 4 of the injection molding machine;

[0156] A mold closing control module 21, which is connected to the controller through the first safety switch 3, and is used to control the mold moving proportional valve 2 to enter the mold closing mode according to the mold closing signal sent by the controller, so as to control the mold moving oil cylinder assembly 9 to drive the moving platen to perform the mold closing operation.

[0157] A mold opening control module 22, which is separately arranged from the mold closing control module 21 and is connected to the controller, and is used to control the mold moving proportional valve 2 to enter the mold opening mode according to the mold opening signal sent by the controller, so as to control the mold moving oil cylinder assembly 9 to drive the moving platen to perform the mold opening operation.

[0158] When the safety door 4 is opened, the first safety switch 3 is disconnected, and the mold closing control module 21 is disconnected from the controller.

[0159] Thus, when the safety door 4 is opened, the connection between the mold clamping control module 21 and the controller is disconnected. The mold clamping control module 21 cannot receive any signals sent by the controller, including the mold clamping signal. Therefore, it cannot control the mold moving proportional valve 2 to enter the mold clamping mode. The A port and P port of the mold moving proportional valve 2 are in a non-connected state, and the B port and T port of the mold moving proportional valve 2 are also in a non-connected state. In this case, even if the pressure oil flows out of the A port of the one-way main valve 11 and into the B port of the one-way main valve 11, since the A port and P port of the mold moving proportional valve 2 are not connected, the pressure oil cannot enter the mold clamping cavity 92, and thus the mold clamping operation cannot be performed. Moreover, even if a small amount of pressure oil enters the mold clamping cavity 92, since the B port and T port of the mold moving proportional valve 2 are not connected, that is, the pressure oil cannot return to the oil return tank 8, the mold clamping operation cannot be performed either.

[0160] It can be seen that the mold moving control system provided by the present invention can also improve the use safety and reliability of the injection molding machine, and there is no need to add a safety valve to avoid safety accidents, and the cost generated by adding a safety valve can also be reduced.

[0161] In addition, since the mold clamping control module 21 and the mold opening control module 22 are separately arranged, the mold clamping mode and the mold opening mode of the mold moving proportional valve 2 can be made non-interfering. The disconnection of the mold clamping control module 21 from the controller will not affect the connection between the mold opening control module 22 and the controller. The mold opening control module 22 can still communicate with the controller, so that the mold moving oil cylinder assembly 9 can still perform the mold opening operation, which can meet more application requirements of the injection molding machine and can improve the versatility and practicality of the injection molding machine to a certain extent.

[0162] Also for safety considerations, in some embodiments, please refer to Figure 3 , the mold moving control system provided by the present invention may further include:

[0163] A second safety switch 5 for detecting the opening and closing state of the safety door 4.

[0164] When the safety door 4 is opened, the second safety switch 5 is disconnected, and the controller is further configured to control the mold clamping oil return pilot valve 71 to be powered off, so that the A port and B port of the mold clamping oil return valve 7 are in a non-connected state, and the oil return passage between the mold moving proportional valve 2 and the oil return tank 8 is in a non-connected state.

[0165] Thus, when the safety door 4 is open, the safety door 4 will continuously trigger the second safety switch 5 to be in the off state, thereby ensuring that the oil return pilot valve 71 is always de-energized. Therefore, the A port and the P port of the oil return pilot valve 71 are connected, and the A port of the oil return pilot valve 71 is also connected to the pilot chamber of the mold-closing oil return valve 7. Furthermore, the A port and the B port of the mold-closing oil return valve 7 are in a non-connected state. Based on this, if a mold-closing operation is to be performed, since the mold-closing cavity 92 is the rod chamber and the mold-opening cavity 91 is the rodless chamber, and the area of the mold-opening cavity 91 is larger than the area of the mold-closing cavity 92, the pressure oil discharged from the mold-opening cavity 91 must be greater than the pressure oil entering the mold-closing cavity 92, and the pressure oil discharged from the mold-opening cavity 91 must flow back to the return tank to achieve the mold-closing operation.

[0166] However, since the A port and the B port of the mold-closing oil return valve 7 are in a non-connected state, the pressure oil flowing out of the mold-opening cavity 91 cannot return, that is, the oil return path between the mold-moving proportional valve 2 and the oil return tank 8 is in a non-connected state. Without the ability to return oil, the mold-closing operation cannot be performed, which can also ensure the safety of the use and maintenance of the injection molding machine. If combined with the upper-layer safety scheme, a better safety effect can be achieved.

[0167] Similarly, for safety considerations, in some embodiments, please refer to Figure 3 , the mold-moving control system provided by the present invention may further include:

[0168] A spool position detection module 23, disposed in the mold-moving proportional valve 2, for detecting the spool position information of the main spool of the mold-moving proportional valve 2 and sending it to the controller.

[0169] When the safety door 4 is open, if the controller determines that the mold-moving proportional valve 2 is in the mold-closing mode according to the spool position information, the controller controls the injection molding machine to stop running.

[0170] The spool position detection module 23 may adopt a module for detecting the spool position in related technologies. For example, the spool position detection module 23 may be a module that outputs a corresponding voltage signal according to the detected spool position. Based on this, the spool position information may be a voltage signal. Correspondingly, the controller may pre-store the correspondence between the voltage signal and the working mode of the mold-moving proportional valve 2. For example, when the voltage signal is in the first interval, the working mode corresponding to the mold-moving proportional valve 2 is the mold-opening mode; when the voltage signal is in the second interval, the working mode corresponding to the mold-moving proportional valve 2 is the off mode, in which the A port, the B port, the P port, and the T port of the mold-moving proportional valve 2 are not connected to each other; when the voltage signal is in the third interval, the working mode corresponding to the mold-moving proportional valve 2 may be the mold-closing mode.

[0171] The first interval, the second interval, and the third interval can be configured according to the working pressure parameters corresponding to the mold shifting proportional valve 2 in different modes. For example, assume that the working voltage range of the mold shifting proportional valve 2 corresponding to the mold closing mode is [+1.3V, +10V], the working voltage range corresponding to the mold opening mode is [-10V, -1.3V], and the working voltage range corresponding to the off mode is (-1.3V, +1.3V). Then, when the controller determines that the voltage signal detected by the spool position detection module 23 belongs to the range of [+1.3V, +10V], the controller considers that the mold shifting proportional valve 2 is in the mold closing mode. And when the safety door 4 is opened, the mold closing operation should not be performed. Therefore, for safety reasons, the controller will control the injection molding machine to stop running so that the mold shifting oil cylinder assembly 9 cannot perform the mold closing operation.

[0172] Similarly, for safety reasons, in some embodiments, please refer to Figure 3 , the mold shifting control system provided by the present invention may further include:

[0173] A mold shifting position detection module 94, which is used to detect the template position information of the moving template in the two-platen injection molding machine and send it to the controller.

[0174] In some examples, the mold shifting position detection module 94 may be an electronic scale, but is not limited thereto.

[0175] When the safety door 4 is opened, if the controller determines that the mold shifting oil cylinder assembly 9 performs a mold closing operation according to the template position information, the controller controls the injection molding machine to stop running, or controls the injection molding machine to stop running and issues an alarm message for characterizing the abnormality of the mold shifting oil cylinder assembly 9.

[0176] Since the mold shifting position detection module 94 can detect the template position information of the moving template in real time, and the template position information is the current position recorded above. If the template position information becomes smaller and the value of the decrease within a unit time exceeds the set value, it indicates that the moving template has a mold closing operation. Therefore, the controller can determine whether the mold shifting oil cylinder assembly 9 performs a mold closing operation according to the change of the template position information. The set value can be obtained based on experience or experiments, and the present invention does not limit this.

[0177] Therefore, in the case where no mold closing control is performed, if the controller determines that the mold shifting oil cylinder assembly 9 performs a mold closing operation according to the template position information, for safety reasons, the controller controls the injection molding machine to stop running so that the injection molding machine cannot perform the mold closing operation.

[0178] In addition, when the safety door 4 is open, the mold clamping control module 21 does not control the mold moving proportional valve 2 to enter the mold clamping mode, but if there is still a mold clamping operation on the moving platen, it may be because the mold moving oil cylinder assembly 9 is abnormal. Therefore, in addition to controlling the injection molding machine to stop running, the controller can also send an alarm message indicating the abnormality of the mold moving oil cylinder assembly 9 to prompt relevant personnel to perform abnormality detection or maintenance on the mold moving oil cylinder assembly 9, so as not to affect the subsequent normal use requirements of the injection molding machine.

[0179] Similarly, for safety considerations, in some embodiments, to avoid excessive pressure in the mold clamping cavity 92 damaging the mold, or causing defects in the molded parts or equipment failures, please refer to Figure 3 , the mold moving control system provided by the present invention may further include:

[0180] A pressure sensor 95, disposed in the mold clamping cavity 92, for detecting the pressure information of the mold clamping cavity 92 and sending it to the controller.

[0181] When the controller determines that the pressure in the mold clamping cavity 92 is greater than the set pressure threshold according to the pressure information, it controls the injection molding machine to stop running, or controls the injection molding machine to stop running and issues an alarm message for characterizing overpressure of the mold moving oil cylinder assembly 9.

[0182] Thereby, it is possible to avoid the phenomenon that the mold clamping cavity 92 continues to work under overpressure, resulting in mold damage, or molded part damage, or equipment failure, which is beneficial to extending the service life of the mold moving control system and reducing the maintenance cost.

[0183] Any embodiment in the mold moving control system provided by the present invention can be combined with each other to form a new solution as long as there is no combination contradiction.

[0184] Corresponding to the embodiments of the mold moving control system, the present invention also provides an injection molding machine, which includes the mold moving control system in any of the above embodiments.

[0185] Among them, for the control principle of realizing the stable operation of the moving platen and the technical principle of realizing safe operation of the injection molding machine, reference can be made to the relevant records in the embodiments of the mold moving control system, which will not be elaborated here.

[0186] The above embodiments are only the preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. For those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A mold moving control system, characterized in that, It includes a one-way main valve, a mold moving proportional valve, a mold moving oil cylinder assembly, a mold opening oil replenishing valve and a controller; Port A of the one-way main valve is used to connect with the main pressure oil circuit of the injection molding machine, and port B is connected with port P of the mold moving proportional valve; Port T of the mold moving proportional valve is used to connect with the oil return tank of the injection molding machine, port A is connected with the mold clamping cavity in the mold moving oil cylinder assembly, and port B is connected with the mold opening cavity in the mold moving oil cylinder assembly; Port P of the mold opening oil replenishing valve is connected with port B of the one-way main valve, and port B is connected with the mold opening cavity; The controller is used to control the mold moving proportional valve to enter the mold opening mode in the mold opening mode. In the mold opening mode, port P and port B of the mold moving proportional valve are communicated, and its port A and port T are communicated; The controller is also used to control the mold opening oil replenishing valve to be energized when the moving platen performs a deceleration operation in the mold opening mode. In the energized state, port P and port B of the mold opening oil replenishing valve are communicated, so that the pressure oil in the main pressure oil circuit passes through the one-way main valve and the mold opening oil replenishing valve and enters the mold opening cavity; When the moving platen performs a deceleration operation in the mold opening mode, the controller is also used to: Based on the distance between the current position of the moving platen and the mold opening end position, and the maximum rated mold opening deceleration, calculate the mold opening calculated speed corresponding to the current position of the moving platen; wherein, the maximum rated mold opening deceleration is based on the formula Calculated as represents the maximum rated mold opening deceleration, represents the rated working pressure of the moving mold cylinder assembly, represents the cylinder diameter of the moving mold cylinder assembly, represents the diameter of the moving mold piston rod in the moving mold cylinder assembly, represents the mass of the moving platen with the heaviest mold installed; Take the smaller one of the mold opening calculated speed and the median of the mold opening set speed corresponding to the current position of the moving platen as the mold opening control speed; Based on the mold opening control speed, calculate the mold opening control voltage value corresponding to the current position of the moving platen through a pre-constructed linear function; Control the opening size of the mold moving proportional valve according to the mold opening control voltage value.

2. The mold shifting control system according to claim 1, wherein It also includes: A proportional pressure valve, connected between port B of the one-way main valve and the oil return tank; When the moving platen performs a deceleration operation in the mold opening mode, if the pressure in the mold opening cavity is higher than the conduction pressure of the proportional pressure valve, the pressure oil overflowing from the mold opening cavity flows back to the oil return tank through the proportional pressure valve.

3. The transfer mold control system according to claim 2, wherein, The controller is also used to increase the conduction pressure of the proportional pressure valve when the moving platen performs a deceleration operation in the mold opening mode and the distance between the moving platen and the set mold opening end position belongs to the first set distance range, so as to prevent the pressure oil overflowing from the mold opening cavity from flowing back to the oil return tank through the proportional pressure valve.

4. The transfer mold control system according to claim 2, wherein, The controller is also used to control the ports A, B, P and T of the mold moving proportional valve to be not communicated with each other when the moving platen reaches the set mold opening end position in the mold opening mode, and control the mold opening oil replenishing valve to be de-energized.

5. The transfer die control system according to any one of claims 1 to 4, characterized in that, It also includes: A mold clamping oil return assembly, connected between port T of the mold moving proportional valve and the oil return tank, which includes a mold clamping oil return valve and an oil return pilot valve; port A of the mold clamping oil return valve is connected with port T of the mold moving proportional valve, port B is connected with the oil return tank; port P of the oil return pilot valve is connected between port T of the mold moving proportional valve and port A of the mold clamping oil return valve, port A is connected with the pilot cavity of the mold clamping oil return valve, and port T is connected with port B of the mold clamping oil return valve; And a fast component, including a fast valve and a fast pilot valve, wherein the A port of the fast valve is connected between the T port of the mold moving proportional valve and the A port of the mold clamping oil return valve, and the B port is connected to the mold opening cavity; the P port of the fast pilot valve is connected to the mold opening cavity, the A port is connected to the pilot cavity of the fast valve, and the T port is connected to the B port of the mold clamping oil return valve; The controller is further configured to control the oil return pilot valve to be de-energized and the fast pilot valve to be energized when the moving platen does not perform a deceleration operation in the mold opening mode, so that the pressure oil flowing out of the mold clamping cavity flows through the fast valve to the mold opening cavity.

6. The transfer mold control system according to claim 5, characterized in that, The controller is further configured to control the oil return pilot valve and the fast pilot valve to be energized when the moving platen does not perform a deceleration operation in the mold clamping mode, so that the pressure oil flowing out of the mold opening cavity is diverted to the fast valve and flows back to the oil return tank through the mold clamping oil return valve; And / or, the controller is further configured to control the oil return pilot valve to be energized and the fast pilot valve to be de-energized when the moving platen performs a deceleration operation in the mold clamping mode.

7. The transfer mold control system according to claim 1, wherein, Further comprising: A one-way pilot valve, connected between the pilot cavity of the one-way main valve and the P port of the mold moving proportional valve; The P port of the one-way pilot valve is connected to the pilot cavity of the one-way main valve, the A port is used to be connected to the main pressure oil circuit, and the B port is connected between the B port of the one-way main valve and the P port of the mold moving proportional valve; The controller is further configured to control the one-way pilot valve to be energized in the mold opening mode or the mold clamping mode.

8. A two-platen injection molding machine, characterized in that, Comprising the mold moving control system according to any one of claims 1 to 7.

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