Mold moving control system and two-plate injection molding machine

Abstract

The invention discloses a mold moving control system and a two-plate injection molding machine, and relates to the technical field of injection molding equipment, and the system comprises a one-way main valve, a mold moving proportional valve, a mold moving oil cylinder assembly, a mold opening oil supplementing valve and a controller; a port A of the one-way main valve is connected with a main pressure oil path of the injection molding machine, and a port B is connected with a port P of the mold moving proportional valve; a port T of the mold moving proportional valve is used for being connected with an oil return tank of the injection molding machine, a port A is connected with a mold closing cavity in the mold moving oil cylinder assembly, and a port B is connected with a mold opening cavity in the mold moving oil cylinder assembly; a port P of the mold opening oil supplementing valve is connected with a port B of the one-way main valve, and a port B is connected with the mold opening cavity; the controller is used for controlling the mold moving proportional valve to be powered on in the mold opening mode and controlling the mold opening oil supplementing valve to be powered on under the condition that the movable mold plate executes speed reduction operation in the mold opening mode, so that pressure oil of the main pressure oil way enters the mold opening cavity through the one-way main valve and the mold opening oil supplementing valve. And the vacuum phenomenon of the mold opening cavity is avoided, so that the mold opening movement stability of the movable mold plate is improved.

Description

Technical Field

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

[0002] Injection molding machine is a main molding equipment that uses plastic molding molds to make thermoplastic plastics or thermosetting plastics into plastic products of various shapes. The work process of injection molding machine involves mold closing and mold opening. The purpose of mold closing is to make the movable mold plate and the static mold plate close together to form a closed molding space; mold opening is generally the next step after mold closing, which separates the movable mold plate from the static mold plate to facilitate the removal of the molded parts.

[0003] When the movable template needs to slow down and brake during the mold opening operation, because the mold opening cavity of the two-plate 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 high back pressure. At this time, the opening of the mold shifting proportional valve needs to be reduced to provide high back pressure. However, the reduction in the opening of the mold shifting proportional valve will cause the mold opening cavity to be unable to replenish oil in time, which may cause vacuum in the mold opening cavity. If vacuum occurs in the mold opening cavity, the movable template will rebound and vibrate after the mold is opened, and the smoothness of the mold opening movement is poor. Summary of the invention

[0004] In order to solve the technical problem of poor mold opening motion stability of the movable template in the two-platen injection molding machine in the above-mentioned related art, the purpose of the present invention is to provide a mold shifting control system and a two-platen injection molding machine.

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

[0006] A first aspect of an embodiment of the present invention provides a mold shifting control system, including a one-way main valve, a mold shifting proportional valve, a mold shifting 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 shifting proportional valve;

[0008] The T port of the mold shifting 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 shifting oil cylinder assembly, and the B port is connected to the mold opening cavity in the mold shifting 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 shifting proportional valve to enter the mold opening mode in the mold opening mode, and the P port of the mold shifting proportional valve in the mold opening mode is connected to the B port, and the A port is connected to the T port;

[0011] The controller is also used to control the mold opening oil replenishing valve 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 in the energized state is connected with the B port, so that the pressure oil of 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 optional embodiment, when the movable platen performs a deceleration operation in the mold opening mode, the controller is further used to control the opening size of the mold shifting proportional valve according to the current position of the movable platen and the maximum mold opening rated deceleration.

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

[0014] According to the current position of the movable platen and the maximum rated deceleration of mold opening, the mold opening calculation speed corresponding to the current position of the movable platen is calculated;

[0015] The smallest value between the mold opening calculation speed and the mold opening setting speed corresponding to the current position of the movable platen is used as the mold opening control speed;

[0016] The mold opening control voltage value corresponding to the current position of the movable plate is calculated based on the mold opening control speed by using a pre-constructed linear function;

[0017] The opening size of the mold shifting proportional valve is controlled according to the mold opening control voltage value.

[0018] In an optional embodiment, the mold shifting control system further includes:

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

[0020] When the movable plate performs a deceleration operation in the mold opening mode, if the pressure of 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 return oil tank through the proportional pressure valve.

[0021] In an optional embodiment, the controller is also used to increase the conduction pressure of the proportional pressure valve when the movable template performs a deceleration operation in the mold opening mode and the distance between the movable template 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 return oil tank through the proportional pressure valve.

[0022] In an optional embodiment, the controller is also used to control the A port, B port, P port and T port of the mold shifting proportional valve to be disconnected from each other and control the mold opening oil replenishing valve to cut off power when the movable mold plate reaches the set mold opening end position in the mold opening mode.

[0023] In an optional embodiment, the mold shifting control system further includes:

[0024] A mold closing oil return assembly is connected between the T port of the mold shifting proportional valve and the oil return tank, and comprises 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 shifting 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 shifting proportional valve and the A port of the mold closing oil return valve, the A port is connected to the pilot cavity 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 component, including an express valve and an express pilot valve, wherein the A port of the express valve is connected between the T port of the mold shifting proportional valve and the A port of the mold closing oil return valve, and the B port is connected to the mold opening cavity; the P port of the express pilot valve is connected to the mold opening cavity, the A port is connected to the pilot cavity 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 also used to control the oil return pilot valve to be powered off and control the express pilot valve 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 flows to the mold opening cavity through the express valve.

[0027] In an optional embodiment, the controller is further used to control the mold opening oil replenishing valve to be energized when the movable mold plate does not perform a deceleration operation in the mold opening mode.

[0028] In an optional embodiment, the controller is also used to control the oil return pilot valve and the express pilot valve to be energized when the movable template does not perform a deceleration operation in the mold closing mode, so that the pressure oil flowing out of the mold opening cavity is diverted to the express valve and returned to the oil return tank through the mold closing oil return valve.

[0029] In an optional embodiment, the controller is further used to control the oil return pilot valve to be energized and the express pilot valve to be deenergized when the movable plate performs a deceleration operation in the mold closing mode.

[0030] In an optional embodiment, the mold shifting control system further includes:

[0031] A one-way pilot valve is connected between the pilot cavity of the one-way main valve and the P port of the mold shifting 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 connect 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 shifting proportional valve;

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

[0033] A second aspect of an embodiment of the present invention further provides a two-platen injection molding machine, comprising a mold shifting control system according to any one of the items provided in the first aspect.

[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 port A of the one-way main valve is greater than the pressure at port B, the pressure oil can flow from port A of the one-way main valve to port B and flow into the mold shifting proportional valve, thus realizing the normal operation of the mold opening mode or mold closing mode; and when the pressure oil supply to the mold shifting control system stops, the pressure at port A of the one-way main valve is less than the pressure at port B, and the spring force applied to the pilot chamber of the one-way main valve will close the valve core, thus preventing the pressure oil at port B of the one-way main valve from flowing to port A of the one-way main valve. This can not only ensure that the movable platen cannot rebound in the mold closing direction in the mold opening mode, but also ensure that the movable platen cannot rebound in the mold opening direction in the mold closing mode, while also solving the rebound problem of spring mold closing; it can improve the movement stability of the movable platen;

[0036] On the other hand, when the movable plate performs a deceleration operation in the mold opening mode, the braking force is completely provided by the mold closing cavity, but the oil pressure area of ​​the mold closing cavity is small and can only provide braking force by high back pressure. Therefore, in order to achieve the purpose of deceleration, the opening of the mold shifting proportional valve needs to be reduced to provide high back pressure. However, the reduction in the opening of the mold shifting proportional valve will cause the mold opening cavity to be unable to replenish oil in time, or even unable to replenish oil, which may cause vacuum in the mold opening cavity. Therefore, by configuring another mold opening cavity replenishment branch that does not rely on pressure difference to achieve oil supply - the branch where the mold opening oil replenishment valve is located, and when the movable plate performs a deceleration operation in the mold opening mode, the mold opening oil replenishment valve is controlled to be energized, so that the pressure oil of the main pressure oil circuit can enter the mold opening cavity without resistance through the one-way main valve and the mold opening oil replenishment valve. Thereby, when the opening of the mold shifting proportional valve is reduced, the pressure oil can still pass through the branch where the mold opening oil replenishing valve is located to properly replenish the mold opening cavity with oil, which can not only avoid the vacuum in the mold opening cavity, but also avoid affecting the deceleration and braking effect, and ensure that the moving template will not rebound or vibrate due to the vacuum in the mold opening cavity, thereby greatly improving the smoothness of the mold opening movement. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A structural schematic diagram of a mold shifting control system provided by the present invention;

[0038] Figure 2 A schematic structural diagram of another mold shifting control system provided by the present invention;

[0039] Figure 3 This is a schematic structural diagram of another mold shifting 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 replenishment valve, 13-proportional pressure valve, 2-mold shifting proportional valve, 21-mold closing control module, 22-mold opening control module, 23-valve core position detection module, 3-first safety switch, 4-safety door, 5-second safety switch, 6-express valve, 61-express pilot valve, 7-mold closing oil return valve, 71-return oil pilot valve, 8-return oil tank, 9-mold shifting cylinder assembly, 91-mold opening cavity, 92-mold closing cavity, 93-mold shifting piston rod, 94-mold shifting position detection module, 95-pressure sensor. DETAILED DESCRIPTION

[0042] In order to facilitate the understanding of the present invention, the technical solutions and advantages of the invention are further described in detail below in conjunction with the accompanying drawings and embodiments. The mechanisms or methods not described in the present invention can refer to the prior art. The specific structure and features of the present invention are described below in an exemplary manner, which should not constitute any limitation to the present invention. At the same time, any of the technical features mentioned below (including implicit or disclosed), as well as any technical features directly displayed or implied in the figure, can continue to be arbitrarily combined or deleted between 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 accompanying 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 thoroughly and comprehensively understood.

[0043] See also Figure 1 , Figure 1 This is a structural schematic diagram of a mold shifting control system provided by the present invention. The mold shifting control system provided by the present invention is applied to a two-plate injection molding machine, which includes a one-way main valve 11, a mold shifting proportional valve 2, a mold shifting cylinder assembly 9, a mold opening oil replenishing valve 12 and a controller.

[0044] The A port of the one-way main valve 11 is used to be connected to the main pressure oil circuit 1 of the injection molding machine, and the B port is connected to the P port of the mold shifting 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, in order to ensure that the mold shifting 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 shifting proportional valve 2, the controller can control the mold shifting proportional valve 2 to enter the mold opening mode, so that the P port of the mold shifting proportional valve 2 is connected to the B port, and its A port is connected to the T port. Based on this, when the pressure oil entering the A port of the one-way main valve 11 gradually increases, and the pressure of the A port of the one-way main valve 11 is greater than the pressure of its pilot cavity, the spring at the A port will be pushed open, so that the A port of the one-way main valve 11 is connected to the B port. Therefore, the pressure oil will flow out of the A port of the one-way main valve 11 and flow through the P port and the B port of the mold shifting proportional valve 2 in turn, so as to enter the mold opening cavity 91 of the mold shifting cylinder assembly 9, and then flow out from the mold closing cavity 92 through the A port and the T port of the mold shifting proportional valve 2 to the return oil tank 8. During this process, the pressure of the mold opening cavity 91 is greater than the pressure of the mold closing cavity 92, so the mold shifting piston rod 93 arranged in the mold closing cavity moves away from the mold cavity 91, thereby driving the movable mold plate connected to the mold shifting piston rod 93 to move away from the static mold plate, thereby realizing the mold opening operation.

[0054] In the process of performing the mold opening operation, in order to ensure that the movable mold plate can be braked to the set mold opening end position in a timely and stable manner, after the movable mold plate runs to a certain position, the controller will control the movable mold plate to perform a deceleration operation. In order to achieve the purpose of deceleration, due to the structural configuration of the mold closing cavity 92 and the mold opening cavity 91, the opening of the mold shifting proportional valve 2 needs to be reduced to reduce the pressure oil flowing into the mold opening cavity 91. However, the reduction in the opening of the mold shifting proportional valve 2 may result in a lack of oil flow into the mold opening cavity 91, which may easily cause a vacuum phenomenon in the mold opening cavity 91. Therefore, in this case, the controller controls the mold opening oil replenishment valve 12 to be energized, and the P port of the mold opening oil replenishment valve 12 in the energized state is connected to the B port. In this way, even if the mold shifting 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 the mold opening oil replenishing valve 12, which is a branch without resistance. The 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, thereby avoiding the vacuum in the mold opening cavity 91, and realizing that the movable template will not rebound or vibrate due to the vacuum in the mold opening cavity 91, which can improve the stability of the mold opening movement and will not affect 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 low, which can better ensure that the pressure in the mold closing cavity 92 can compete with the mold opening cavity 91, and can further improve the effect and stability of the deceleration brake.

[0055] Therefore, the mold shifting control system of the present invention can not only effectively avoid the vacuum in the mold opening cavity 91 and improve the stability of the mold opening movement of the movable mold plate, but also ensure the deceleration and braking effect of the movable mold plate, thereby effectively improving the mold opening stability and reliability of the two-platen injection molding machine.

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

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

[0058] In step S200, the smallest value between the mold opening calculation speed and the mold opening setting speed corresponding to the current position of the movable platen is used as the mold opening control speed;

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

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

[0061] In order to ensure the mold shifting efficiency of the movable template, and then ensure the output efficiency of the two-plate injection molding machine, the movable template can start to decelerate and stop at a certain position, without the need to perform deceleration and braking operations at all positions during the entire mold shifting process. Therefore, in the mold opening scenario, a deceleration section can be selected between the set mold opening starting position and the set mold opening ending position of the movable template. One of the endpoints of the deceleration section is between the mold opening starting position and the mold opening ending position, which can be selected according to actual needs or experience, and the other endpoint is the mold opening ending position. In this way, the mold opening deceleration position range can be obtained. Correspondingly, the distance between the mold opening starting 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] Therefore, when it is detected that the current position of the movable template is in the mold opening deceleration position range, it can be considered that the movable template is performing a deceleration operation. In order to ensure that the movable template can stop at the set mold shifting end position in a timely and accurate manner, the above steps S100 to S400 can be executed.

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

[0064] As an example, the mold transfer position detection module may be an electronic ruler, but is not limited thereto.

[0065] In the process of executing step S100, the formula Calculated, among which, Indicates the mold opening calculation speed, Indicates the distance between the current position of the moving plate and the end position of mold opening. Indicates the maximum rated deceleration of the moving platen when opening the mold.

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

[0067] It can be understood that in order to obtain the maximum mold opening rated deceleration, 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 of the two-platen injection molding machine when it contains the heaviest mold allowed to be installed;

[0069] Rated working pressure of mold transfer cylinder assembly 9 , unit: MPa;

[0070] Cylinder diameter of mold transfer cylinder assembly 9 , unit: mm;

[0071] Diameter of mold shifting piston rod 93 in mold shifting cylinder assembly 9 , unit: mm;

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

[0073] 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 maximum rated mold closing flow rate available for mold closing The acquisition is for the consideration of mold closing mode and can be ignored in mold opening mode.

[0075] Based on this, the maximum mold opening rated deceleration It 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 between force and pressure. The meaning of each letter in the formula can be found in the relevant records above and will not be repeated here. The unit can be mm / .

[0078] After calculating the mold opening calculation speed corresponding to the current position of the movable template through step S100, the mold opening calculation speed corresponding to the current position can be compared with the mold opening setting speed, wherein the mold opening setting speed is user-defined, indicating at which position or in which position range the user wants the movable template to perform the mold opening operation and at what speed.

[0079] If the comparison result indicates that the calculated mold opening speed corresponding to the current position of the movable platen is less than or equal to the set mold opening speed corresponding to the current position, it means that the set mold opening speed has exceeded the maximum acceptable speed that can ensure that the movable platen can be reliably and stably stopped at the end position of the mold opening. Therefore, in order to ensure the stability and accurate stopping of the movable platen, the mold opening control will be based on the calculated mold opening speed instead of the set mold opening speed set by the user.

[0080] On the contrary, if the comparison result indicates that the calculated mold opening speed corresponding to the current position of the movable template is greater than the set mold opening speed corresponding to the current position, it means that the set mold opening speed has not exceeded the maximum acceptable speed that can ensure that the movable template can be reliably and stably braked at the end position of the mold opening. Therefore, in order to ensure user experience, mold opening control can be performed based on user needs at this time.

[0081] Therefore, in step S200, the smallest value between the mold opening calculation speed and the mold opening setting speed corresponding to the current position of the movable platen is used as the mold opening control speed. If the mold opening calculation speed and the mold opening setting speed are equal, the mold opening calculation speed is used as the mold opening control speed.

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

[0083] For example, assuming the linear function ,in, and are the coefficients of the function, which are known values. is the mold opening speed, Indicates the mold opening control voltage. Based on this, in the process of executing step S300, the mold opening calculation speed can be Substitute into In, at this time The value of is the corresponding mold opening control voltage value.

[0084] In some embodiments, the present invention further provides a corresponding linear function construction scheme, and the linear function construction process includes:

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

[0086] In step S012, the mold opening speed is taken as the independent variable and the mold opening control voltage is taken as the dependent variable. The mold opening linear function is constructed 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; wherein the minimum mold opening speed is 0.

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

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

[0089]

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

[0091] After obtaining the maximum rated mold opening speed, step S012 may be performed, with the mold opening speed as the independent variable and the mold opening control voltage as the dependent variable, based on two coordinate points: and , based on relevant mathematical principles, we can construct a linear function for opening the mold. Indicates the maximum open-mode control voltage, Indicates the minimum open-mode control voltage.

[0092] For example, assuming that in the case of mold opening operation, the maximum mold opening control voltage that can be achieved by mold shift proportional valve 2 is is -10V, based on the maximum open-mode control voltage , which can make the opening speed of the movable mold plate reach the maximum rated opening speed , so we can get the coordinate point . Assume that the minimum mold opening control voltage that can be achieved by mold shift proportional valve 2 is is -1.3V, based on this minimum open-mode control voltage , the opening speed of the movable mold plate can reach 0, so the coordinate point 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 numerical value following the sign. The sign is only used to distinguish the control voltage for mold closing operation from the control voltage for mold opening operation.

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

[0095] Therefore, the mold opening control voltage value corresponding to the current position of the movable plate can be calculated based on the mold opening control speed by calling a linear function.

[0096] Next, step S400 may be performed to control the opening size of the mold shifting proportional valve 2 using the mold opening control voltage value calculated in step S300.

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

[0098]

[0099] in, Indicates the maximum rated mold closing deceleration, and its unit is also mm / . The maximum rated mold closing speed, unit: mm / s. The meanings of other letters can be found in the above related records and will not be repeated here.

[0100] In addition, since the above-mentioned acquisition scheme of the mold opening non-deceleration position range and the mold opening deceleration position range does not take into account the motion performance of the machine itself, but is customized by the user, it is easy to cause the final mold opening deceleration position range to have excess or insufficient distance, and the excess distance may increase the mold shifting time of the movable platen, which is not conducive to improving production efficiency, while the insufficient distance may cause the movable platen to have insufficient deceleration distance for braking. Therefore, in order to solve these technical problems, in some embodiments, the present invention also provides another acquisition scheme of the mold opening non-deceleration position range and the mold opening deceleration position range, that is, the controller is also used to obtain the mold opening non-deceleration position range of the movable platen in the mold opening mode, including:

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

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

[0103] In step Sa3, the mold opening non-deceleration position range is determined according to the set mold opening starting position of the movable platen and the target deceleration distance.

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

[0105] In the process of executing step Sa1, the formula The minimum deceleration distance is calculated, where Indicates the minimum deceleration distance, in mm. Indicates the maximum rated mold opening speed, correspondingly, It represents the square of the maximum rated mold opening speed. Indicates the maximum rated deceleration for mold opening.

[0106] Then, in the process of executing step Sa2, the formula Calculate the target deceleration distance, It is the deceleration distance coefficient preset in the mold opening mode, which can be customized by the user or the system default value can be used.

[0107] After obtaining the target deceleration distance, step Sa3 can be executed. Taking the mold opening starting position as zero as an example, [mold opening starting position, mold opening end position The position range corresponding to the target deceleration distance) is used as the mold opening non-deceleration position range.

[0108] Accordingly, the [Mold opening end position The position range corresponding to the target deceleration distance and the mold opening end position is used as the mold opening deceleration position range.

[0109] Therefore, by incorporating the motion performance of the movable platen to obtain the mold opening non-deceleration position range and the mold opening deceleration position range, it is possible to better ensure that the movable platen stops promptly and accurately at the end position of the mold shifting, and to better ensure the motion stability of the movable platen. On this basis, combined with the control scheme of steps S100 to S400, a better braking technical effect can be achieved - the movable platen is locked promptly and accurately at the set mold opening end position.

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

[0111] In some embodiments, in order to ensure that the position of the movable platen has the same standard in the mold closing operation and the mold opening operation, and thus better ensure the operation effect of the movable platen, the mold closing end position corresponding to the movable platen in the mold closing operation and the mold opening start position corresponding to the movable platen in the mold opening operation are the same, both are zero positions. In addition, the mold closing start position corresponding to the movable platen in the mold closing operation and the mold opening end position corresponding to the movable platen in the mold opening operation are the same.

[0112] Based on the embodiments shown in steps Sa1 to Sa3, in order to ensure that the obtained mold opening deceleration position range can more reliably ensure that the movable platen stops at the mold opening end position in a timely and accurate manner, in some embodiments, the present invention also provides another mold opening deceleration position range acquisition scheme, that is, the controller is also used to obtain the mold opening deceleration position range of the movable platen in the mold opening mode, including:

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

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

[0115] After executing step Sa3, steps Sb1 to Sb2 can be executed. In the process of executing step Sb1, the maximum set mold opening speed within the mold opening non-deceleration position range is first obtained, and then the maximum set mold opening speed is calculated by formula The actual deceleration distance required at the maximum set mold opening speed is calculated, where: Indicates the maximum set mold opening speed of the movable platen within the mold opening non-deceleration position range. The meanings of other letters are as described above. In the case of Can be deleted.

[0116] After the actual deceleration distance required by the movable platen is obtained through step Sb1, step Sb2 can be executed to determine the mold opening deceleration position range corresponding to the movable platen according to the actual deceleration distance and the set mold opening end position. For example, [Mold opening end position The position range corresponding to the actual deceleration distance and the mold opening end position is used as the mold opening deceleration position range.

[0117] Since the maximum set mold opening speed of the movable template is customized by the user, and the movable template will not run at a speed exceeding the maximum set mold opening speed, the position of the movable template in the mold opening process is divided into a mold opening non-deceleration position range and a mold opening deceleration position range, and the mold opening deceleration position range is determined according to the maximum set mold opening speed of the movable template in the mold opening non-deceleration section and the maximum mold opening rated deceleration of the movable template, so that the mold opening deceleration position range can better meet the distance requirements of the movable template to accurately and reliably decelerate to the mold opening end position. On this basis, after the movable template enters the deceleration section, the corresponding mold opening calculation speed is calculated in real time according to the current position of the movable template and the maximum mold opening rated deceleration, and the mold opening calculation speed calculated each time is compared with the corresponding mold opening setting speed, and the one with the smallest value is selected to control the mold opening corresponding to the current position of the movable template, so that the movable template can be ensured to stop at the set mold opening end position in time no matter where it runs during the deceleration section. Therefore, through the combination of the above two technical levels, it is possible to better lock the movable template in the mold opening end position in a timely and accurate manner. The same technical effect can be achieved by adopting the same technical solution under the mold closing operation.

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

[0119] Therefore, by utilizing the mold opening control speed to control both the opening of the mold shifting proportional valve 2 and the mold opening flow of the main pressure oil circuit 1, not only can the mold opening brake effect be improved by combining the two, but also the oil consumption in the oil circuit can be saved to avoid energy waste.

[0120] In some examples, a mapping relationship table between the mold shifting speed and the mold shifting flow rate can be constructed in advance based on the correlation between the mold shifting speed and the mold shifting flow rate of the main oil circuit. The mapping relationship table can be called to obtain the mold opening flow rate corresponding to the current mold opening control speed, and based on the mold opening flow rate, the valve opening size between the main pressure oil circuit 1 and the oil supply tank can be controlled, or the speed of the servo motor used to drive 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-platen injection molding machine according to the mold closing control speed.

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

[0123] Similarly, the controller controls the mold closing flow 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 according to the mold closing control speed, the cylinder diameter of the mold shifting cylinder assembly 9 and the diameter of the mold shifting piston rod 93 in the mold shifting cylinder assembly 9.

[0124] Based on this, the mold closing flow corresponding to the current position of the moving plate and mold opening flow They can be calculated by the following formulas:

[0125]

[0126]

[0127] In the above formula, the mold closing flow corresponding to the current position of the movable platen is and mold opening flow The unit is L / min. Indicates the mold closing control speed corresponding to the current position of the moving platen. It indicates the mold opening control speed corresponding to the current position of the movable platen, and the meaning of other letters can be found in the relevant records above.

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

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

[0130] When the movable mold plate performs a deceleration operation in the mold opening mode, if the pressure of the mold opening cavity 91 is higher than the proportional pressure valve 13 , the pressure oil overflowing from the mold opening cavity 91 flows back to the return oil tank 8 through the proportional pressure valve 13 .

[0131] Therefore, when the movable template performs a deceleration operation in the mold opening mode, the main pressure oil can provide pressure oil to the mold opening cavity 91 according to the conduction pressure, thereby realizing the control of the amount of pressure oil entering the mold opening cavity 91 to avoid affecting the deceleration effect. Moreover, during the deceleration process, if the pressure of 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 into the return oil tank 8 through the mold shifting proportional valve 2 and the proportional pressure valve 13, thereby avoiding the servo motor power from constantly changing due to changes in the pressure of the mold opening cavity 91, thereby ensuring that the servo motor can output a stable amount of pressure oil with stable servo power, thereby achieving speed stability of the movable template during the mold opening deceleration process.

[0132] In some embodiments, in order to ensure the movement stability of the movable template in the process of approaching the mold opening end position, the controller is also used to increase the conduction pressure of the proportional pressure valve 13 when the movable template performs a deceleration operation in the mold opening mode and the distance between the movable template 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 91 from flowing back to the return oil 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 needs, and the present invention does not limit this. Since the opening of the mold shifting proportional valve 2 may be smaller when the movable template is close to the mold opening end position, the conduction pressure of the proportional pressure valve 13 is increased to prevent the pressure oil overflowing from the mold opening cavity 91 from flowing back to the return oil tank 8 through the proportional pressure valve 13, thereby ensuring that the mold opening cavity 91 maintains a relatively stable pressure, avoiding the overflow of pressure oil affecting the pressure balance of the mold opening cavity 91 and the mold closing cavity 92, and thus effectively ensuring the stability of the movable template when braking.

[0134] In some embodiments, in order to ensure that the movable template is stably braked at the mold opening end position, the controller is also used to control the A port, B port, P port and T port of the mold shifting proportional valve 2 to be disconnected from each other when the movable template reaches the set mold opening end position in the mold opening mode, and control the mold opening oil replenishing valve 12 to cut off power.

[0135] Thus, the pressure oil supply to the mold opening cavity 91 and the mold closing cavity 92 can be cut off, thereby ensuring that the movable platen 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, in order to enable the movable platen to open the mold more quickly to improve the production efficiency of the injection molding machine, please refer to Figure 3 , Figure 3 : is a structural schematic diagram of another mold shifting control system provided by the present invention. The mold shifting control system of the present invention may also 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 controlled to be energized all the time. After the mold opening oil replenishing valve 12 is energized, another oil circuit branch can be provided for the pressure oil flowing out of the B port of the one-way main valve 11 to enter the mold opening cavity 91, that is, the pressure oil flowing out of the main pressure oil circuit 1 can enter the mold opening cavity 91 through the mold shifting 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 diverting the pressure oil, which can reduce the oil flow from the mold shifting proportional valve 2, and then effectively reduce the energy consumption and valve core heating of the mold shifting proportional valve 2, which is beneficial to extend the service life of the mold shifting proportional valve 2. This scheme combined with the scheme 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 closing cavity 92 is a rod cavity, the pressure oil flow rate of the mold opening cavity 91 is much larger than that of the mold closing cavity 92 at the same mold shifting speed. In this way, when the movable mold plate does not perform a deceleration operation in the mold closing mode, since the opening of the mold shifting proportional valve 2 is generally large to ensure the mold closing speed in the non-deceleration section, the pressure oil flow rate flowing into the mold closing cavity 92 is also relatively large. Correspondingly, the pressure oil flow rate flowing out of the mold opening cavity 91 is also larger. If all of these pressure oils flow out of the mold shifting proportional valve 2, it will inevitably lead to more energy consumption of the mold shifting proportional valve 2, and the valve core is also easy to heat up, which may also affect the mold closing speed. Therefore, in order to solve these technical problems, in some embodiments, the controller is also used to control the return oil pilot valve 71 and the express pilot valve 61 to be energized when the movable mold plate does not perform a deceleration operation in the mold closing mode, so that the pressure oil flowing out of the mold opening cavity 91 is diverted to the express valve 6 and returned to the return oil tank 8 through the mold closing oil return valve 7.

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

[0145] When the movable template is in the mold closing mode and no deceleration operation is performed, in order to avoid excessive oil output from the mold shifting proportional valve 2, which may cause the valve core to heat up and lose a lot of energy, and affect the mold closing speed of the movable template, the controller controls the return oil pilot valve 71 and the express pilot valve 61 to be energized. In this way, a part of the pressure oil flowing out of the mold opening cavity 91 will be diverted to the express valve 6, that is, from the B port of the express valve 6 to the A port of the express valve 6, and flow out through the A port of the mold closing oil return valve 7 to the B port of the mold closing oil return valve 7, and then flow into the return oil tank 8 through the B port of the mold closing oil return valve 7.

[0146] Therefore, by diverting the pressure oil flowing out of the open mold cavity 91, the pressure oil flow out of the mold shifting proportional valve 2 can be reduced, thereby effectively reducing the energy consumption and valve core heating of the mold shifting proportional valve 2, which is beneficial to extending the service life of the mold shifting proportional valve 2, and at the same time ensuring the mold closing speed and mold closing movement stability of the movable mold plate.

[0147] When the movable template performs a deceleration operation in the mold closing mode, since the opening of the mold shifting proportional valve 2 will be reduced, the flow of the pressure oil passing through will also be reduced. Therefore, there is no need to continue to control the power supply of the express pilot valve 61, so as to save energy consumption to a certain extent. Based on this, in some embodiments, the controller is also used to control the power supply of the return oil pilot valve 71 and the power supply of the express pilot valve 61 when the movable template 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 be always in the energized state. In the process that the movable template does not perform the deceleration operation, the express pilot valve 61 can also be controlled to be energized, and in the process that the movable template performs the deceleration operation, the express pilot valve 61 can be controlled to be deenergized. Therefore, in the process that the movable template performs the deceleration operation, the oil flowing out of the mold opening cavity 91 can only flow from the B port of the mold shifting proportional valve 2 to the T port, and then flow out to the oil return tank 8 through the A port and the B port of the mold closing oil return valve 7.

[0149] In some embodiments, in order to further ensure the stable operation of the mold closing mode or the mold opening mode, it is avoided that the pressure oil can flow into the mold closing cavity 92 or the mold opening cavity 91 at will because the pressure of the port A of the one-way main valve 11 of the injection molding machine that does not need to perform the mold closing operation and the mold opening operation is greater than the pressure of the port B of the one-way main valve 11, thereby affecting the reliability of the injection molding machine. Please continue to refer to Figure 3 The mold shifting control system provided by the present invention may also include:

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

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

[0152] Therefore, when the movable platen needs to be controlled to perform mold closing or mold opening operation, the one-way pilot valve 111 is controlled to be energized, so that when the pressure of port A of the one-way main valve 11 is greater than the pressure of 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 shifting proportional valve 2. The reliability and safety of the injection molding machine can be guaranteed.

[0153] When the movable template is not needed to perform mold closing and mold opening operations, the controller controls the one-way pilot valve 111 to cut off the power. In this way, the A port and the P port in the one-way pilot valve 111 are connected, and the P port of the one-way pilot valve 111 is connected to the pilot chamber of the one-way main valve 11. The A port of the one-way pilot valve 111 and the A port of the one-way main valve 11 are also 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 that at the A port of the one-way main valve 11. In addition, the pressure of the spring in the pilot chamber maintains the closed state of the A port. Therefore, the A port of the one-way main valve 11 and the B port of the one-way main valve 11 cannot be connected. Therefore, 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 shifting proportional valve 2, and will not cause the movable template to perform the mold shifting operation, thereby ensuring the safety of the injection molding machine after standby or shutdown.

[0154] For security reasons, in some embodiments, please refer to Figure 3 The mold shifting control system provided by the present invention may further include:

[0155] A first safety switch 3, used to detect the open or closed state of a safety door 4 of the injection molding machine;

[0156] The mold closing control module 21 is used to connect with the controller through the first safety switch 3, and is used to control the mold shifting 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 shifting cylinder assembly 9 to drive the movable mold plate to perform the mold closing operation.

[0157] The mold opening control module 22 is separately arranged from the mold closing control module 21 and connected to the controller, and is used to control the mold shifting 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 shifting cylinder assembly 9 to drive the moving mold plate to perform the mold opening operation.

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

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

[0160] It can be seen that the mold shifting control system provided by the present invention can also improve the 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 closing control module 21 and the mold opening control module 22 are arranged separately, the mold closing mode and the mold opening mode of the mold shifting proportional valve 2 will not interfere with each other, and the disconnection of the mold closing 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 shifting 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 security reasons, in some embodiments, see Figure 3 The mold shifting control system provided by the present invention may further include:

[0163] The second safety switch 5 is used to detect the open or closed state of the safety door 4 .

[0164] When the safety door 4 is open, the second safety switch 5 is disconnected, and the controller is also used to control the mold closing oil return pilot valve 71 to be in a power-off state, so that the A port and the B port of the mold closing oil return valve 7 are in a disconnected state, and the oil return passage between the mold shifting proportional valve 2 and the return oil tank 8 is in a disconnected state.

[0165] Therefore, when the safety door 4 is open, the safety door 4 will always trigger the second safety switch 5 to be in the disconnected state, thereby ensuring that the oil return pilot valve 71 is always in the power-off state, so that 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 cavity of the mold closing oil return valve 7, thereby making the A port and the B port of the mold closing oil return valve 7 in a disconnected state. Based on this, if the mold closing operation is to be performed, because the mold closing cavity 92 is a rod cavity and the mold opening cavity 91 is a rodless cavity, the area of ​​the mold opening cavity 91 is larger than the area of ​​the mold closing cavity 92, so 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 reflux 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 not connected, the pressure oil flowing out of the mold opening cavity 91 cannot be returned, that is, the oil return passage between the mold shifting proportional valve 2 and the oil return tank 8 is not connected. If the oil cannot be returned, the mold closing operation cannot be performed, and the safety of the use and maintenance of the injection molding machine can also be guaranteed. If combined with the previous safety solution, a better safety effect can be achieved.

[0167] Also, for security reasons, in some embodiments, see Figure 3 The mold shifting control system provided by the present invention may also include:

[0168] The valve core position detection module 23 is disposed in the mold shifting proportional valve 2 and is used to detect the valve core position information of the main valve core of the mold shifting proportional valve 2 and send the information to the controller.

[0169] When the safety door 4 is opened, if the controller determines that the mold shifting proportional valve 2 is in the mold closing mode according to the valve core position information, the injection molding machine is controlled to stop running.

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

[0171] The first interval, the second interval and the third interval can be configured according to the corresponding working pressure parameters of the mold shifting proportional valve 2 in different modes. For example, assuming 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 disconnection mode is (-1.3V, +1.3V). When the controller determines that the voltage signal detected by the valve core 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 open, 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 cylinder assembly 9 cannot perform the mold closing operation.

[0172] Also, for security reasons, in some embodiments, see Figure 3 The mold shifting control system provided by the present invention may also include:

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

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

[0175] When the safety door 4 is open, if the controller determines that the mold shifting cylinder assembly 9 performs a mold closing operation based on the template position information, the injection molding machine is controlled to stop running, or the injection molding machine is controlled to stop running and an alarm message is issued to indicate that the mold shifting cylinder assembly 9 is abnormal.

[0176] Since the mold shifting position detection module 94 can detect the mold position information of the movable mold plate in real time, the mold position information is also the current position recorded above, and the mold position information is decreasing and the value of the decrease in unit time exceeds the set value, it indicates that the movable mold plate has a mold closing operation, so the controller can determine whether the mold shifting cylinder assembly 9 performs a mold closing operation according to the change of the mold position information. The set value can be obtained according to experience or experiment, and the present invention is not limited to this.

[0177] Therefore, when mold closing control is not performed, if the controller determines that the mold shifting cylinder assembly 9 performs a mold closing operation based on the template position information, the controller controls the injection molding machine to stop running for safety reasons so that the injection molding machine cannot perform a mold closing operation.

[0178] In addition, when the safety door 4 is open, the mold closing control module 21 will not control the mold shifting proportional valve 2 to enter the mold closing mode, but the movable mold plate still has a mold closing operation, which may be because there is an abnormality in the mold shifting cylinder assembly 9. Therefore, in addition to controlling the injection molding machine to stop running, the controller can also issue an alarm message indicating that the mold shifting cylinder assembly 9 is abnormal, so as to prompt relevant personnel to perform abnormal detection or maintenance on the mold shifting cylinder assembly 9 to avoid affecting the subsequent normal use needs of the injection molding machine.

[0179] Similarly, for safety reasons, in some embodiments, to prevent excessive pressure in the mold cavity 92 from damaging the mold, or causing defects in the molded part or equipment failure, please refer to Figure 3 The mold shifting control system provided by the present invention may also include:

[0180] The pressure sensor 95 is disposed in the mold clamping cavity 92 and is used to detect pressure information of the mold clamping cavity 92 and send the pressure information to the controller.

[0181] When the controller determines that the pressure of the mold cavity 92 is greater than the set pressure threshold based on the pressure information, the injection molding machine is controlled to stop running, or the injection molding machine is controlled to stop running and issue an alarm message for indicating that the mold shifting cylinder assembly 9 is overpressured.

[0182] Thereby, it is possible to avoid the mold closing cavity 92 continuing to work under overpressure, which may cause damage to the mold, damage to the molded part, or equipment failure, thereby helping to extend the service life of the mold shifting control system and reduce maintenance costs.

[0183] Any embodiments of the mold shifting 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 shifting control system, the present invention further provides an injection molding machine, which includes the mold shifting control system in any of the above embodiments.

[0185] Among them, the control principle of the injection molding machine to achieve stable operation of the moving platen and the technical principle of achieving safe operation can be found in the relevant records in the mold transfer control system embodiment, which will not be repeated here.

[0186] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. For ordinary technicians in this field, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A mold shifting control system, characterized in that: It includes a one-way main valve, a mold shifting proportional valve, a mold shifting cylinder assembly, a mold opening 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 mold shifting proportional valve; The T port of the mold shifting 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 shifting oil cylinder assembly, and the B port is connected to the mold opening cavity in the mold shifting oil cylinder assembly; 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; The controller is used to control the mold shifting proportional valve to enter the mold opening mode in the mold opening mode, and the P port of the mold shifting proportional valve in the mold opening mode is connected to the B port, and the A port is connected to the T port; The controller is also used to control the mold opening oil replenishing valve 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 in the energized state is connected with the B port, so that the pressure oil of the main pressure oil circuit enters the mold opening cavity through the one-way main valve and the mold opening oil replenishing valve.

2. The mold shifting control system according to claim 1, characterized in that: When the movable platen performs a deceleration operation in the mold opening mode, the controller is further used to control the opening size of the mold shifting proportional valve according to the current position of the movable platen and the maximum mold opening rated deceleration.

3. The mold shifting control system according to claim 2, characterized in that: The process of the controller controlling the opening size of the mold shifting proportional valve according to the current position of the movable mold plate and the maximum rated mold opening deceleration includes: According to the current position of the movable platen and the maximum rated deceleration of mold opening, the mold opening calculation speed corresponding to the current position of the movable platen is calculated; The smallest value between the mold opening calculation speed and the mold opening setting speed corresponding to the current position of the movable platen is used as the mold opening control speed; The mold opening control voltage value corresponding to the current position of the movable plate is calculated based on the mold opening control speed by using a pre-constructed linear function; The opening size of the mold shifting proportional valve is controlled according to the mold opening control voltage value.

4. The mold shifting control system according to claim 1, characterized in that: Also includes: A proportional pressure valve, connected between port B of the one-way main valve and the oil return tank; When the movable plate performs a deceleration operation in the mold opening mode, if the pressure of 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 return oil tank through the proportional pressure valve.

5. The mold shifting control system according to claim 4, characterized in that: The controller is also used to increase the conduction pressure of the proportional pressure valve when the movable template performs a deceleration operation in the mold opening mode and the distance between the movable template 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 return oil tank through the proportional pressure valve.

6. The mold shifting control system according to claim 4, characterized in that: The controller is also used to control the A port, B port, P port and T port of the mold shifting proportional valve to be disconnected from each other and control the mold opening oil replenishing valve to be powered off when the movable mold plate reaches the set mold opening end position in the mold opening mode.

7. The mold transfer control system according to any one of claims 1 to 6, characterized in that: Also includes: A mold closing oil return assembly is connected between the T port of the mold shifting proportional valve and the oil return tank, and comprises 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 shifting 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 shifting proportional valve and the A port of the mold closing oil return valve, the A port is connected to the pilot cavity of the mold closing oil return valve, and the T port is connected to the B port of the mold closing oil return valve; And an express component, including an express valve and an express pilot valve, wherein the A port of the express valve is connected between the T port of the mold shifting proportional valve and the A port of the mold closing oil return valve, and the B port is connected to the mold opening cavity; the P port of the express pilot valve is connected to the mold opening cavity, the A port is connected to the pilot cavity of the express valve, and the T port is connected to the B port of the mold closing oil return valve; The controller is also used to control the oil return pilot valve to be powered off and control the express pilot valve 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 flows to the mold opening cavity through the express valve.

8. The mold transfer control system according to claim 7, characterized in that: The controller is also used to control the oil return pilot valve and the express pilot valve to be energized when the movable platen does not perform a deceleration operation in the mold closing mode, so that the pressure oil flowing out of the mold opening cavity is diverted to the express valve and returned to the oil return tank through the mold closing oil return valve; And / or, the controller is also used to control the oil return pilot valve to be energized and the express pilot valve to be deenergized when the movable template performs a deceleration operation in the mold closing mode.

9. The mold transfer control system according to claim 1, characterized in that: Also includes: A one-way pilot valve connected between the pilot cavity of the one-way main valve and the P port of the mold shifting 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 connect 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 shifting proportional valve; The controller is also used to control the one-way pilot valve to be energized in a mold opening mode or a mold closing mode.

10. A two-platen injection molding machine, characterized in that: The invention comprises the mold shifting control system according to any one of claims 1 to 9.

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