Injection Molding Machine Safety Control System and Injection Molding Machine

Abstract

The present invention discloses an injection molding machine safety control system and an injection molding machine. The system includes a one-way main valve, a mold moving proportional valve, a first safety switch, a mold clamping control module, a mold opening control module, a mold moving oil cylinder assembly, and a controller. The A port of the one-way main valve is connected 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. The T port of the mold moving proportional valve is connected to the oil return tank of the injection molding machine, the A port is connected to the mold clamping 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. The first safety switch is used to detect the opening and closing state of the safety door of the injection molding machine. The mold clamping control module is connected to the controller through the first safety switch. The mold opening control module is separately arranged from the mold clamping control module and is connected to the controller. When the safety door is opened, the first safety switch is disconnected, the mold clamping control module and the controller are disconnected, and the mold clamping control module does not receive a continuous mold clamping control signal, so that the mold moving oil cylinder assembly does not perform a mold clamping operation.

Description

Technical Field

[0001] The present invention relates to the technical field of injection molding equipment, and particularly to an injection molding machine safety control system and an 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 template and the stationary template closely close to form a closed molding space; mold opening is generally the next step after mold closing, and the moving template is separated from the stationary template to facilitate the removal of the molded part. Therefore, after the mold opening operation, the safety door of the injection molding machine is usually opened to take out the molded part.

[0003] In addition, the safety door of the injection molding machine is also opened when it is necessary to clean, replace or adjust the mold, or perform machine debugging, or the machine breaks down, or perform machine maintenance. Therefore, after the safety door is opened, the moving template should be in the mold opening state to perform corresponding operations and protect the safety of the operators. However, in fact, the moving template may perform a mold closing operation for some reasons. If there are operators between or near the moving template and the stationary template at this time, it will seriously affect the safety of the operators' lives. Summary of the Invention

[0004] To solve the above technical problems existing in the prior art, the purpose of the present invention is to provide an injection molding machine safety control system and an injection molding machine, so as to ensure that the moving template is in the mold opening state when the safety door is in the open state, and improve the safety and reliability of the 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 an injection molding machine safety control system, including a one-way main valve, a mold moving proportional valve, a first safety switch, a mold closing control module, a mold opening control module, a mold moving oil cylinder assembly and a controller;

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

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

[0009] The first safety switch is used to detect the opening and closing state of the safety door of the injection molding machine and send the corresponding detection result to the controller;

[0010] The mold clamping control module is connected to the controller through the first safety switch, and is configured to control the mold moving proportional valve to enter the mold clamping mode according to the mold clamping signal continuously sent by the controller, so as to control the mold moving oil cylinder assembly to perform the mold clamping operation;

[0011] The mold opening control module is separately arranged from the mold clamping control module and is connected to the controller, and is configured to control the mold moving proportional valve 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 to perform the mold opening operation;

[0012] When the safety door is opened, the first safety switch is disconnected, the mold clamping control module is disconnected from the controller, and the mold clamping control module does not receive the continuous mold clamping control signal, so that the mold moving oil cylinder assembly does not perform the mold clamping operation.

[0013] In an optional embodiment, when the controller determines that the safety door is opened according to the detection result, the controller issues an alarm message for indicating that the mold moving oil cylinder assembly is prohibited from performing the mold clamping operation.

[0014] In an optional embodiment, the injection molding machine safety control system further includes a mold clamping oil return assembly connected between the T port of the mold moving proportional valve and the oil return tank:

[0015] The mold clamping oil return assembly includes a second safety switch, a mold clamping oil return pilot valve and a mold clamping oil return valve;

[0016] The second safety switch is configured to detect the opening and closing state of the safety door;

[0017] The P port of the mold clamping oil return pilot valve is connected to the T port of the mold moving proportional valve, the A port is connected to the pilot chamber of the mold clamping oil return valve, and the power supply input end of the mold clamping oil return pilot valve is connected to the power supply through the second safety switch;

[0018] The A port of the mold clamping 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;

[0019] When the safety door is opened, the second safety switch is disconnected, the mold clamping oil return pilot valve is in a power-off state, the A port and the B port of the mold clamping oil return valve are not connected, and the oil return passage between the mold moving proportional valve and the oil return tank is not connected.

[0020] In an optional embodiment, the injection molding machine safety control system further includes:

[0021] One-way pilot valve, 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;

[0022] When the safety door is opened, the one-way pilot valve is in a power-off state, the A port and the B port of the one-way main valve are in a non-connected state, and the mold clamping cavity and the main pressure oil circuit are in a non-connected state.

[0023] In an alternative embodiment, the injection molding machine safety control system further includes:

[0024] A spool position detection module, disposed in the mold moving proportional valve, for detecting the spool position information of the main spool of the mold moving proportional valve and sending it to the controller;

[0025] When the controller determines that the safety door is opened according to the detection result, if the controller determines that the mold moving proportional valve is in the mold clamping mode according to the spool 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 for characterizing the abnormality of the mold moving proportional valve is sent.

[0026] In an alternative embodiment, the injection molding machine safety control system further includes:

[0027] A mold opening oil replenishing valve, its P port is connected to the B port of the one-way main valve, the T port is connected to the oil return tank, and the B port is connected to the mold opening cavity;

[0028] When the controller determines that the safety door is opened according to the detection result, if the controller determines that the mold moving proportional valve is in the mold clamping mode according to the spool position information, the mold opening oil replenishing valve is also controlled to be in a powered-on state to connect the B port of the one-way main valve and the mold opening cavity.

[0029] In an alternative embodiment, a mold moving piston rod is disposed in the mold clamping cavity of the injection molding machine safety control system; a mold moving position detection module is disposed on the mold moving piston rod;

[0030] The mold moving position detection module is used to detect the template position information of the moving template in the injection molding machine and send it to the controller;

[0031] When the controller determines that the safety door is opened according to the detection result, if the controller determines that the mold moving oil cylinder assembly performs a mold clamping operation according to 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 for characterizing the abnormality of the mold moving oil cylinder assembly is sent.

[0032] In an alternative embodiment, the injection molding machine safety control system further includes:

[0033] A proportional pressure valve, connected between port B of the one-way main valve and the oil return tank;

[0034] When the controller determines that the safety door is open according to the detection result, the controller controls the proportional pressure valve to be in a conducting state to connect port B of the one-way main valve with the oil return tank.

[0035] In an alternative embodiment, the injection molding machine safety control system further includes:

[0036] A pressure sensor, disposed in the clamping cavity, for detecting the pressure information of the clamping cavity and sending it to the controller;

[0037] When the controller determines that the pressure in the clamping cavity 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 issue an alarm message for characterizing overpressure of the moving die cylinder assembly.

[0038] A second aspect of the embodiments of the present invention further provides an injection molding machine, including the injection molding machine safety control system provided in any one of the above first aspects.

[0039] Compared with the prior art, the present invention has at least the following beneficial effects:

[0040] On the one hand, by configuring a first safety switch between the clamping control module for controlling the moving die proportional valve to enter the clamping mode and the controller, the on-off between the clamping control module and the controller is controlled by the first safety switch. That is, for the clamping control module and the controller to establish communication, the first safety switch must be in a conducting state. Among them, since the control of the clamping mode of the moving die proportional valve by the clamping control module depends on the clamping signal continuously sent by the controller, that is to say, as long as the controller stops providing the clamping signal to the clamping control module, the clamping control module immediately stops clamping control. Therefore, when the safety door is open and the first safety switch is disconnected, it will inevitably cause the clamping control module to be disconnected from the controller, so that the clamping control module will not receive the clamping signal continuously sent by the controller, and further the moving die cylinder assembly cannot perform the clamping operation, realizing that the moving template driven by the moving die cylinder assembly in the injection molding machine is in the open mold state, thereby improving the use safety and reliability of the injection molding machine. Moreover, compared with the related art solution of adding a safety valve in the oil circuit to avoid safety accidents, it can be seen that the present invention can avoid safety accidents without adding a safety valve, so the present invention can also reduce the cost generated by adding a safety valve.

[0041] On the other hand, by configuring the mold moving proportional valve with a separately configured mold clamping control module and mold opening control module, the mold clamping mode and mold opening mode of the mold moving proportional valve can be made non-interfering. The disconnection of the mold clamping control module from the controller will not affect the connection between the mold opening control module and the controller, and the mold opening control module can still communicate with the controller, so that the mold moving oil cylinder assembly 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 FIG. is a schematic structural diagram of a safety control system for an injection molding machine provided by the present invention;

[0043] Figure 2 FIG. is a schematic structural diagram of another safety control system for an injection molding machine provided by the present invention;

[0044] Figure 3 FIG. is a schematic structural diagram of yet another safety control system for an injection molding machine provided by the present invention;

[0045] Figure 4 FIG. is a schematic structural diagram of yet another safety control system for an injection molding machine provided by the present invention;

[0046] Figure 5 FIG. is a schematic structural diagram of yet another safety control system for an injection molding machine provided by the present invention;

[0047] Figure 6 FIG. is a schematic structural diagram of yet another safety control system for an injection molding machine provided by the present invention;

[0048] Figure 7 FIG. is a schematic structural diagram of yet another safety control system for an injection molding machine provided by the present invention;

[0049] Figure 8 FIG. is a schematic structural diagram of yet another safety control system for an injection molding machine provided by the present invention;

[0050] Figure 9 FIG. is a schematic structural diagram of yet another safety control system for an injection molding machine provided by the present invention.

[0051] ICON:

[0052] 1 - Main pressure oil circuit, 11 - One - way main valve, 111 - One - way pilot valve, 12 - Mold - opening oil - replenishing valve, 13 - Proportional pressure valve, 2 - Moving - mold proportional valve, 21 - Clamping - mold 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 - mold oil - return valve, 71 - Clamping - mold oil - return pilot valve, 8 - Oil return tank, 9 - Moving - mold oil cylinder assembly, 91 - Mold - opening cavity, 92 - Clamping - mold cavity, 93 - Moving - mold piston rod, 94 - Moving - mold position detection module, 95 - Pressure sensor. Detailed implementation manners

[0053] For the convenience of understanding 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 are described by way of example below, which should not constitute 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, so as to form more other embodiments that may not be directly or indirectly mentioned in the present invention. The preferred embodiments of the present invention are given 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.

[0054] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of a safety control system for an injection molding machine provided by the present invention. The safety control system for an injection molding machine provided by the present invention is applied to a two - plate injection molding machine, and includes a one - way main valve 11, a moving - mold proportional valve 2, a first safety switch 3, a clamping - mold control module 21, a mold - opening control module 22, a moving - mold oil cylinder assembly 9 and a controller.

[0055] The A port of the one - way main valve 11 is used to connect to the main pressure oil circuit 1 of the injection molding machine, and the B port is connected to the P port of the moving - mold proportional valve 2.

[0056] The T port of the moving - mold 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 clamping - mold cavity 92 in the moving - mold oil cylinder assembly 9, and the B port is connected to the mold - opening cavity 91 in the moving - mold oil cylinder assembly 9.

[0057] The first safety switch 3 is used to detect the open and closed state of the safety door 4 of the injection molding machine, and send the corresponding detection result to the controller. The detection result is used to indicate that the safety door 4 is in the open state, or to indicate that the safety door 4 is in the closed state. Thus, the controller can determine whether the safety door 4 is in the open state or the closed state based on the detection result.

[0058] The mold closing control module 21 is connected to the controller via 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 continuously sent by the controller, so as to control the mold shifting cylinder assembly 9 to perform the mold closing operation.

[0059] 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 perform the mold opening operation.

[0060] When the safety door 4 is open, the first safety switch 3 is disconnected, the mold closing control module 21 is disconnected from the controller, and the mold closing control module 21 does not receive a continuous mold closing control signal, so that the mold moving cylinder assembly 9 does not perform a mold closing operation.

[0061] In the above, the implementation principles of the mold closing control module 21 and the mold opening control module 22 can be referred to in the relevant technology.

[0062] Before applying the injection molding machine safety control system provided by the present invention to the injection molding machine, the injection molding machine safety control system can be connected to the main pressure oil circuit 1, the return oil tank 8, the safety door 4, and the movable template of the injection molding machine in the connection manner described above, wherein the movable template 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 template to perform mold opening or mold closing operations.

[0063] In addition, the controller included in the safety control system for the injection molding machine provided by the present invention can be configured separately, or the controller provided by the injection molding machine can be reused.

[0064] It should be understood that the injection molding machine safety control system provided by the present invention can be produced as a set with the 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.

[0065] The working principle of the injection molding machine safety control system provided by the present invention is described below:

[0066] In a scenario where a mold clamping operation needs to be performed, the safety door 4 needs to be closed so that the first safety switch 3 is in a conducting state, enabling the connection between the controller and the mold clamping control module 21. Subsequently, the controller can send a continuous mold clamping signal to the mold clamping control module 21. After receiving the continuous mold clamping control signal, the mold clamping control module 21 controls the mold moving proportional valve 2 to enter the mold clamping mode, causing the A port and the P port of the mold moving proportional valve 2 to communicate, and the B port and the T port to communicate. Based on this, as the hydraulic oil flowing into the A port of the one-way main valve 11 gradually increases, when 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, causing the A port and the B port of the one-way main valve 11 to communicate. Therefore, the hydraulic oil will flow out of the B port from the A port of the one-way main valve 11 and sequentially pass through the P port and the A port of the mold moving proportional valve 2 to enter the mold clamping cavity 92 of the mold moving oil cylinder assembly 9, and then flow out to the oil return tank 8 from the mold opening cavity 91 through the B port and the T port of the mold moving proportional valve 2. During this process, the pressure in the mold clamping cavity 92 is greater than the pressure in the mold opening cavity 91. Therefore, the mold moving piston rod 93 disposed in the mold clamping cavity 92 moves towards the mold opening cavity 91, thereby driving the moving template connected to the mold moving piston rod 93 to move towards the stationary template, achieving the mold clamping operation.

[0067] However, when the safety door 4 is open, the safety door 4 will continuously trigger the first safety switch 3 to be in an open state. Therefore, the connection between the mold clamping control module 21 and the controller is also disconnected. It can be seen that the mold clamping control module 21 fails to receive the continuous mold clamping signal sent by the controller, so it is unable to control the mold moving proportional valve 2 to enter the mold clamping mode. The A port and the P port of the mold moving proportional valve 2 are in a non-connected state, and the B port and the T port of the mold moving proportional valve 2 are also in a non-connected state. In this case, even if the hydraulic oil flows out of the B port from the A port of the one-way main valve 11, since the A port and the P port of the mold moving proportional valve 2 are not connected, the hydraulic oil cannot enter the mold clamping cavity 92, and thus the mold clamping operation cannot be performed. Moreover, even if a small amount of hydraulic oil enters the mold clamping cavity 92, since the B port and the T port of the mold moving proportional valve 2 are not connected, that is, the hydraulic oil cannot return to the oil return tank 8, the mold clamping operation cannot be performed either.

[0068] It can be seen that the injection molding machine safety control system provided by the present invention can 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. It can also reduce the cost generated by adding a safety valve.

[0069] In a scenario where a mold opening operation needs to be performed, the opening and closing state of the safety door 4 can be ignored because there is no risk of the moving platen and the stationary platen clamping a human body during the mold opening operation, and the on / off between the mold opening control module 22 and the controller is independent of the state of the first safety switch 3. Therefore, in this scenario, the controller can send a continuous mold opening signal to the mold opening control module 22. After receiving the mold opening control signal, the mold opening control module 22 controls the mold moving proportional valve 2 to enter the mold opening mode according to the mold opening control signal, so that port A of the mold moving proportional valve 2 is connected to port T, and port B and port P are connected. Based on this, as the hydraulic oil entering port A of the one-way main valve 11 gradually increases, when the pressure at port A of the one-way main valve 11 is greater than the pressure in its pilot chamber, the spring at port A will be pushed open, causing port A and port B of the one-way main valve 11 to be connected. Therefore, the hydraulic oil will flow out from port A to port B of the one-way main valve 11, and successively pass through port P and port B 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 to the oil return tank 8 from the mold clamping cavity 92 through port A and port T of the mold moving proportional valve 2. During this process, the pressure in the mold opening cavity 91 is greater than the pressure in the mold clamping cavity 92. Therefore, the mold moving piston rod 93 arranged in the mold clamping cavity 92 moves in a direction away from the mold opening cavity 91, and further drives the moving platen connected to the mold moving piston rod 93 to move in a direction away from the stationary platen, realizing the mold opening operation.

[0070] Thus, the mold clamping mode and the mold opening mode of the mold moving proportional valve 2 do not interfere with each other. 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, and 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.

[0071] In some embodiments, to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add an additional layer of safety mechanism, that is, when the controller determines that the safety door 4 is open according to the above detection results, the controller can also issue an alarm message indicating that the mold moving oil cylinder assembly 9 is prohibited from performing the mold clamping operation, which can remind relevant personnel not to input a mold clamping command to the injection molding machine, and can better improve the safety of using or maintaining the injection molding machine when the safety door 4 is open.

[0072] In some embodiments, to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add an additional layer of safety mechanism, that is, please refer to Figure 2 , Figure 2Schematic structural diagram of another injection molding machine safety control system provided by the present invention. The injection molding machine safety control system provided by the present invention may further include a mold closing oil return assembly connected between the T port of the mold moving proportional valve 2 and the oil return tank 8: The mold closing oil return assembly includes a second safety switch 5, a mold closing oil return pilot valve 71, and a mold closing oil return valve 7.

[0073] The second safety switch 5 is used to detect the opening and closing state of the safety door 4.

[0074] The P port of the mold closing oil return pilot valve 71 is connected to the T port of the mold moving proportional valve 2, the A port is connected to the pilot chamber of the mold closing oil return valve 7, and the power supply input terminal of the mold closing oil return pilot valve 71 is connected to the power supply through the second safety switch 5.

[0075] The A port of the mold closing oil return valve 7 is connected to the T port of the mold moving proportional valve 2, and the B port is connected to the oil return tank 8.

[0076] When the safety door 4 is open, the second safety switch 5 is disconnected, the mold closing oil return pilot valve 71 is in a power-off state, the A port and the B port of the mold closing 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.

[0077] Thus, 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 mold closing oil return pilot valve 71 is always in the power-off state. Therefore, the A port and the P port of the mold closing oil return pilot valve 71 are connected, and the A port of the mold closing oil return pilot valve 71 is also connected to the pilot chamber of the mold closing oil return valve 7, further causing the A port and the B port of the mold closing oil return valve 7 to be 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 non-rod chamber, the area of the mold opening cavity 91 is larger than the area of the mold closing cavity 92. Therefore, the hydraulic oil discharged from the mold opening cavity 91 must be greater than the hydraulic oil entering the mold closing cavity 92, and the hydraulic oil discharged from the mold opening cavity 91 must flow back to the return tank to achieve the mold closing operation.

[0078] However, since the A port and the B port of the mold closing oil return valve 7 are in a non-connected state, the hydraulic oil flowing out of the mold opening cavity 91 cannot return oil, that is, the oil return passage between the mold moving proportional valve 2 and the oil return tank 8 is in a non-connected state, and no oil return means that the mold closing operation cannot be performed. This can further improve the safety of using or maintaining the injection molding machine when the safety door 4 is open.

[0079] In some embodiments, to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention may add an additional layer of safety mechanism, that is, please refer to Figure 3 , Figure 3Schematic structural diagram of another injection molding machine safety control system provided by the present invention. The injection molding machine safety control system provided by the present invention may further include:

[0080] One-way pilot valve 111, connected between the pilot chamber of the one-way main valve 11 and the P port of the mold moving proportional valve 2; 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 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 moving proportional valve 2.

[0081] When the safety door 4 is opened, the one-way pilot valve 111 is in a power-off state, the A port and the B port of the one-way main valve 11 are not connected, and the mold clamping cavity 92 and the main pressure oil circuit 1 are not connected.

[0082] Thus, when the safety door 4 is opened, the controller can control the one-way pilot valve 111 to be in a power-off state, so that the A port and the P port of the one-way pilot valve 111 are connected. Since the A port of the one-way pilot valve 111 is connected to the main pressure oil circuit 1, the hydraulic oil flowing into the one-way pilot valve 111 from the A port will flow into the pilot chamber of the one-way main valve 11 from the P port of the one-way pilot valve 111. Coupled with the fact that the pressure-receiving area of the pilot chamber of the one-way main valve 11 is larger than the pressure-receiving area of the A port of the one-way main valve 11, and a spring for applying pressure to the A port is also provided in the pilot chamber of the one-way main valve 11, it can be ensured that the pressure in the pilot chamber of the one-way main valve 11 is greater than the pressure in the A port of the one-way main valve 11, thereby making the A port and the B port of the one-way main valve 11 not connected.

[0083] It can be seen that even if the mold clamping control module 21 controls the mold moving proportional valve 2 to be in the mold clamping mode at this time, since the A port and the B port of the one-way main valve 11 are not connected, the mold clamping cavity 92 and the main pressure oil circuit 1 are also not connected, and the hydraulic oil cannot enter the mold clamping cavity 92, so that the mold moving oil cylinder assembly 9 cannot perform the mold clamping operation, thereby improving the safety of using or maintaining the injection molding machine when the safety door 4 is opened.

[0084] In some embodiments, to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention may add a layer of safety mechanism, that is, please continue to refer to Figure 1 , the injection molding machine safety control system provided by the present invention may further include:

[0085] A spool position detection module 23, arranged 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.

[0086] When the controller determines that the safety door 4 is opened based on the above detection result, 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 operating, or controls the injection molding machine to stop operating and issues an alarm message for characterizing that the mold moving proportional valve 2 is abnormal.

[0087] The spool position detection module 23 can adopt a module for detecting the spool position in related technologies. For example, the spool position detection module 23 can be a module that outputs a corresponding voltage signal according to the detected spool position. Based on this, the spool position information can be a voltage signal. Correspondingly, the controller can 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 disconnecting mode, in which the A port, B port, P port, and 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 can be the mold closing mode.

[0088] The first interval, the second interval, and the third interval can be configured according to the working pressure parameters corresponding to the mold moving proportional valve 2 in different modes. For example, assuming that the working voltage range corresponding to the mold closing mode of the mold moving proportional valve 2 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 disconnecting 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 moving proportional valve 2 is in the mold closing mode. And when the controller determines that the safety door 4 is opened based on the above detection result, the mold closing operation should not be performed. Therefore, for safety considerations, the controller will control the injection molding machine to stop operating so that the mold moving oil cylinder assembly 9 cannot perform the mold closing operation.

[0089] In addition, the controller can also issue an alarm message for characterizing that the mold moving proportional valve 2 is abnormal to prompt relevant personnel to perform fault detection or maintenance on the mold moving proportional valve 2. Because when the safety door 4 is opened, the communication between the controller and the mold closing control module 21 is disconnected, and it is impossible for the mold closing control module 21 to control the mold moving proportional valve 2 to enter the mold closing mode. Therefore, it is possible that the mold moving proportional valve 2 has a fault. For example, the mold moving proportional valve 2 has a valve jamming phenomenon, and the spool is stuck at the position where the A port of the mold moving proportional valve 2 can be connected to the P port. Therefore, to ensure the safety and stability of the subsequent use of the injection molding machine, an alarm message for characterizing that the mold moving proportional valve 2 is abnormal can also be issued in a timely manner to avoid affecting the subsequent operation of the injection molding machine.

[0090] In some embodiments, based on the previous embodiment, to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add an additional layer of safety mechanism, that is, please refer to Figure 4 , Figure 4 which is a schematic structural diagram of another injection molding machine safety control system provided by the present invention. The injection molding machine safety control system provided by the present invention may further include:

[0091] A mold opening oil replenishing valve 12, whose P port is connected to the B port of the one-way main valve 11, the T port is connected to the oil return tank 8, and the B port is connected to the mold opening cavity 91.

[0092] When the controller determines that the safety door 4 is opened based on the above detection results, if the controller determines that the mold moving proportional valve 2 is in the mold closing mode according to the spool position information, it also controls the mold opening oil replenishing valve 12 to be in the energized state to connect the B port of the one-way main valve 11 and the mold opening cavity 91.

[0093] Thus, when the controller determines that the safety door 4 is opened based on the detection results, if the controller determines that the mold moving proportional valve 2 is in the mold closing mode according to the spool position information, it may indicate that the mold moving proportional valve 2 has a valve sticking phenomenon, and the spool is stuck at a position where the A port and the P port of the mold moving proportional valve 2 can be connected. Therefore, to further reduce the risk, the controller can also control the mold opening oil replenishing valve 12 to be in the energized state. After being energized, the P port and the B port of the mold opening oil replenishing valve 12 are connected, so that even if there is hydraulic oil flowing out of the B port of the one-way main valve 11, the flowing hydraulic oil will flow through two branches. One branch is the oil circuit where the P port and the A port of the mold moving proportional valve 2 are located, and the other branch is the oil circuit where the P port and the B port of the mold opening oil replenishing valve 12 are located. Therefore, the hydraulic oil will enter the mold closing cavity 92 and the mold opening cavity 91 respectively, making the mold closing cavity 92 and the mold opening cavity 91 connected by the hydraulic oil and having the same pressure, so that the mold closing operation cannot be performed.

[0094] In addition, since the mold closing cavity 92 is a rod chamber and its area is smaller than that of the mold opening cavity 91 which is a rodless chamber, therefore, when the pressures of the mold closing cavity 92 and the mold opening cavity 91 are the same, due to the larger area of the mold opening cavity 91 than that of the mold closing cavity 92, the mold moving oil cylinder assembly 9 can only perform the mold opening operation and will not perform the mold closing operation.

[0095] Moreover, when the spool of the mold moving proportional valve 2 is stuck at a position where the P port and the B port of the mold moving proportional valve 2 are connected, regardless of whether the mold opening oil replenishing valve 12 is energized or not, the hydraulic oil will flow into the mold opening cavity 91 and flow out to the oil return tank 8 through the mold closing cavity 92. Therefore, the mold moving oil cylinder assembly 9 can only perform the mold opening operation and will not perform the mold closing operation.

[0096] Thus, when the safety door 4 is opened, the use safety of the injection molding machine can be further improved.

[0097] In some embodiments, to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add an additional layer of safety mechanism, that is, please refer to Figure 5 , Figure 5 FIG. is a schematic structural diagram of another injection molding machine safety control system provided by the present invention. In the injection molding machine safety control system provided by the present invention, a moving die piston rod 93 is arranged in the die clamping cavity 92; a moving die position detection module 94 is arranged on the moving die piston rod 93.

[0098] The moving die position detection module 94 is used to detect the template position information of the moving template in the injection molding machine and send it to the controller. In some examples, the moving die position detection module 94 can be an electronic scale, but is not limited thereto.

[0099] When the controller determines that the safety door 4 is opened according to the above detection result, if the controller determines that the moving die oil cylinder assembly 9 performs a die clamping 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 issue an alarm message indicating that the moving die oil cylinder assembly 9 is abnormal.

[0100] Since the moving die position detection module 94 can detect the template position information of the moving template in real time, and if the template position information becomes smaller and the value of the decrease per unit time exceeds the set value, it indicates that the moving template has a die clamping operation. Therefore, the controller can determine whether the moving die oil cylinder assembly 9 performs a die clamping 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.

[0101] Therefore, in the case where no die clamping control is performed, if the controller determines that the moving die oil cylinder assembly 9 performs a die clamping 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 a die clamping operation.

[0102] In addition, when the safety door 4 is open, the die clamping control module 21 does not control the moving die proportional valve 2 to enter the die clamping mode, but if the moving template still has a die clamping operation, it may be because the moving die oil cylinder assembly 9 is abnormal. Therefore, in addition to controlling the injection molding machine to stop running, the controller can also issue an alarm message indicating that the moving die oil cylinder assembly 9 is abnormal to prompt relevant personnel to perform abnormal detection or maintenance on the moving die oil cylinder assembly 9 to avoid affecting the subsequent normal use requirements of the injection molding machine.

[0103] In some embodiments, to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add an additional layer of safety mechanism, that is, please refer to Figure 6 , Figure 6The schematic structural diagram of another injection molding machine safety control system provided by the present invention. The injection molding machine safety control system provided by the present invention may further include:

[0104] A proportional pressure valve 13 is connected between port B of the one-way main valve 11 and the oil return tank 8.

[0105] When the controller determines that the safety door 4 is opened according to the above detection result, the controller controls the proportional pressure valve 13 to be in a conducting state to connect port B of the one-way main valve 11 with the oil return tank 8.

[0106] Thus, when the safety door 4 is opened, to ensure that there is no mold closing operation, the controller can control the proportional pressure valve 13 to be in a conducting state. For example, the pressure of the proportional pressure valve 13 is set to 0, so that the hydraulic oil at any pressure at port B of the one-way main valve 11 can directly drain back to the return tank through the proportional pressure valve 13 without passing through the mold moving proportional valve 2, thereby preventing the injection molding machine from performing a mold closing operation, and further improving the safety of using or maintaining the injection molding machine when the safety door 4 is opened.

[0107] In some embodiments, to avoid damage to the mold due to excessive pressure in the mold closing cavity 92, or to prevent defects in the molded parts or equipment failures, the injection molding machine safety control system provided by the present invention can add an additional safety mechanism, that is, please refer to Figure 7 , Figure 7 The schematic structural diagram of another injection molding machine safety control system provided by the present invention. The injection molding machine safety control system provided by the present invention may further include:

[0108] A pressure sensor 95 is disposed in the mold closing cavity 92 for detecting the pressure information of the mold closing cavity 92 and sending it to the controller.

[0109] When the controller determines that the pressure in the mold closing 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 issue an alarm message indicating overpressure of the mold moving oil cylinder assembly 9.

[0110] Thus, it is possible to avoid the phenomenon that the mold closing cavity 92 continues to work under overpressure, resulting in mold damage, or damage to the molded parts, or equipment failure, which is beneficial to extending the service life of the injection molding machine safety control system and reducing the maintenance cost.

[0111] It should be noted that one or more of the above safety mechanisms provided by the present invention can be combined and applied to achieve a better safety control effect. As an example, all of the above safety mechanisms can be combined. Please refer to Figure 8 , Figure 8It is a schematic structural diagram of another injection molding machine safety control system provided by the present invention. It can be seen that at this time, the injection molding machine safety control system can include all the devices, functions, and technical effects mentioned in the above-mentioned embodiments. Figure 8 For the technical principle and technical effect of the shown injection molding machine safety control system, reference can be made to the relevant records above, and details will not be elaborated here.

[0112] In some embodiments, to enable the injection molding machine control safety system to have the functions of rapid mold opening and closing, please refer to Figure 9 , Figure 9 It is a schematic structural diagram of another injection molding machine safety control system provided by the present invention. The injection molding machine safety control system provided by the present invention may further include:

[0113] A special valve 6, whose port A is connected between the T port of the mold moving proportional valve 2 and the P port of the mold closing return oil pilot valve 71, and port B is connected to the mold opening cavity 91;

[0114] And a special pilot valve 61, whose P port is connected between the B port of the special valve 6 and the mold opening cavity 91, port A is connected to the pilot cavity of the special valve 6, and port T is connected to the oil return tank 8.

[0115] When the special pilot valve 61 is de-energized, its port A is communicated with port P, and port B is communicated with port T; when the special pilot valve 61 is energized, its port A is communicated with port T, and port B is communicated with port P.

[0116] For the relevant principle of using the special pilot valve 61 to achieve rapid mold closing and opening of the injection molding machine, reference can be made to the related technology, and details will not be elaborated here.

[0117] Corresponding to the embodiments of the injection molding machine safety control system, the present invention also provides an injection molding machine, which includes the injection molding machine safety control system in any of the above embodiments.

[0118] For the technical principle of the injection molding machine to achieve safety control, reference can be made to the relevant records in the embodiments of the injection molding machine safety control system, and details will not be elaborated here.

[0119] 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. An injection molding machine safety control system, characterized in that, It includes a one-way main valve, a mold moving proportional valve, a first safety switch, a mold clamping control module, a mold opening control module, a mold moving oil cylinder assembly, a mold clamping oil return assembly 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 moving proportional valve; 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 clamping 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; The first safety switch is used to detect the opening and closing state of the safety door of the injection molding machine and send the corresponding detection result to the controller; The mold clamping control module is connected to the controller through the first safety switch, and is used to control the mold moving proportional valve to enter the mold clamping mode according to the mold clamping signal continuously sent by the controller, so as to control the mold moving oil cylinder assembly to perform the mold clamping operation; The mold opening control module is separately arranged from the mold clamping control module and is connected to the controller, and is used to control the mold moving proportional valve 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 to perform the mold opening operation; The mold clamping oil return assembly is connected between the T port of the mold moving proportional valve and the oil return tank: the mold clamping oil return assembly includes a second safety switch, a mold clamping oil return pilot valve and a mold clamping oil return valve; The second safety switch is used to detect the opening and closing state of the safety door; The P port of the mold clamping oil return pilot valve is connected to the T port of the mold moving proportional valve, the A port is connected to the pilot cavity of the mold clamping oil return valve, and the power supply input end of the mold clamping oil return pilot valve is connected to the power supply through the second safety switch; The A port of the mold clamping 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; When the safety door is opened, the first safety switch is disconnected, the mold clamping control module is disconnected from the controller, the mold clamping control module does not receive a continuous mold clamping control signal, so that the mold moving oil cylinder assembly does not perform the mold clamping operation, and the second safety switch is disconnected, the mold clamping oil return pilot valve is in a power-off state, the A port and the B port of the mold clamping oil return valve are in a non-connected state, and the oil return passage between the mold moving proportional valve and the oil return tank is in a non-connected state.

2. The injection molding machine safety control system according to claim 1, wherein When the controller determines that the safety door is opened according to the detection result, the controller issues an alarm message indicating that the mold moving oil cylinder assembly is prohibited from performing the mold clamping operation.

3. The injection molding machine safety control system according to claim 1, characterized in that, It also includes: A one-way pilot valve, which is 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 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 moving proportional valve; When the safety door is opened, the one-way pilot valve is in a power-off state, the A port and the B port of the one-way main valve are in a non-connected state, and the mold clamping cavity and the main pressure oil circuit are in a non-connected state.

4. The injection molding machine safety control system according to claim 1, wherein, It also includes: A spool position detection module is arranged in the mold moving proportional valve, and is used for detecting the spool position information of the main spool of the mold moving proportional valve and sending it to the controller; When the controller determines that the safety door is opened according to the detection result, if the controller determines that the mold moving proportional valve is in the mold closing mode according to the spool position information, it controls the injection molding machine to stop running, or controls the injection molding machine to stop running and issue an alarm message for characterizing the abnormality of the mold moving proportional valve.

5. The injection molding machine safety control system according to claim 4, wherein It further includes: A mold opening oil replenishing valve, its P port is connected to the B port of the one-way main valve, its T port is connected to the oil return tank, and its B port is connected to the mold opening cavity; When the controller determines that the safety door is opened according to the detection result, if the controller determines that the mold moving proportional valve is in the mold closing mode according to the spool position information, it also controls the mold opening oil replenishing valve to be energized to connect the B port of the one-way main valve and the mold opening cavity.

6. The injection molding machine safety control system according to claim 1, wherein A mold moving piston rod is arranged in the mold closing cavity; a mold moving position detection module is arranged on the mold moving piston rod; The mold moving position detection module is used for detecting the template position information of the moving template in the injection molding machine and sending it to the controller; When the controller determines that the safety door is opened according to the detection result, if the controller determines that the mold moving oil cylinder assembly performs a mold closing operation according to the template position information, it controls the injection molding machine to stop running, or controls the injection molding machine to stop running and issue an alarm message for characterizing the abnormality of the mold moving oil cylinder assembly.

7. The safety control system of an injection molding machine according to any one of claims 1-6, characterized in that It further includes: A proportional pressure valve is connected between the B port of the one-way main valve and the oil return tank; When the controller determines that the safety door is opened according to the detection result, the controller controls the proportional pressure valve to be in a conducting state to connect the B port of the one-way main valve and the oil return tank.

8. The safety control system of an injection molding machine according to claim 1, wherein, It further includes: A pressure sensor is arranged in the mold closing cavity and is used for detecting the pressure information of the mold closing cavity and sending it to the controller; When the controller determines that the pressure in the mold closing cavity 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 issue an alarm message for characterizing the overpressure of the mold moving oil cylinder assembly.

9. An injection molding machine, characterized in that, It includes the injection molding machine safety control system according to any one of claims 1-8.

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