Injection molding machine safety control system and injection molding machine

Abstract

The invention discloses an injection molding machine safety control system and an injection molding machine. The injection molding machine safety control system comprises 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. 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 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; the first safety switch is used for detecting opening and closing states of a safety door of the injection molding machine; the mold closing control module is connected with the controller through the first safety switch; the mold opening control module and the mold closing control module are separately arranged and are connected with the controller; and under the condition that the safety door is opened, the first safety switch is switched off, the mold closing control module and the controller are disconnected, and the mold closing control module does not receive continuous mold closing control signals, so that the mold moving oil cylinder assembly does not execute mold closing operation.

Description

Technical Field

[0001] The present invention relates to the technical field of injection molding equipment, and in particular 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 plastic molding molds to make thermoplastics or thermosetting plastics into plastic products of various shapes. The workflow of an 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. Therefore, after the mold opening operation, the safety door of the injection molding machine is usually opened to remove the molded parts.

[0003] In addition, the safety door of the injection molding machine will also be opened when it is necessary to clean, replace or adjust the mold, or to debug the machine, or when the machine fails, or to perform machine maintenance. Therefore, after the safety door is opened, the movable platen should be in the open mold state in order to perform the corresponding operations and protect the safety of the operators. However, in fact, the movable platen may be closed for some reason. If there are operators between or near the movable platen and the static platen at this time, it will seriously affect the life safety of the operators. Summary of the invention

[0004] In order to solve the technical problems existing in the above-mentioned prior art, the purpose of the present invention is to provide an injection molding machine safety control system and an injection molding machine, so that when the safety door is in the open state, the movable mold plate can be ensured to be in the open mold state, thereby improving the safety and reliability of the 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 safety control system for an injection molding machine, comprising a one-way main valve, a mold shifting proportional valve, a first safety switch, a mold closing control module, a mold opening control module, a mold shifting cylinder assembly, 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 first safety switch is used to detect the open and closed state of the safety door of the injection molding machine and send the corresponding detection result to the controller;

[0010] The mold closing control module is connected to the controller via the first safety switch, and is used to control the mold shifting proportional valve to enter a mold closing mode according to the mold closing signal continuously sent by the controller, so as to control the mold shifting cylinder assembly to perform a mold closing operation;

[0011] The mold opening control module is separately arranged from the mold closing control module and connected to the controller, and is used to control the mold shifting proportional valve 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 to perform the mold opening operation;

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

[0013] In an optional embodiment, when the controller determines that the safety door is open based on the detection result, the controller issues an alarm message indicating that the mold shifting cylinder assembly is prohibited from performing a mold closing operation.

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

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

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

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

[0018] 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;

[0019] When the safety door is open, the second safety switch is disconnected, the mold closing oil return pilot valve is in a power-off state, the A port and the B port of the mold closing oil return valve are in a disconnected state, and the oil return passage between the mold shifting proportional valve and the oil return tank is in a disconnected state.

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

[0021] 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;

[0022] When the safety door is open, 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 disconnected state, and the mold clamping cavity and the main pressure oil circuit are in a disconnected state.

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

[0024] A valve core position detection module is provided in the mold shifting proportional valve, and is used to detect valve core position information of a main valve core of the mold shifting proportional valve, and send the information to the controller;

[0025] When the controller determines that the safety door is open based on the detection result, if the controller determines that the mold shifting proportional valve is in the mold closing mode based on the valve core 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 proportional valve is abnormal.

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

[0027] A mold opening oil replenishing valve, wherein the 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 open according to the detection result, if the controller determines that the mold shifting proportional valve is in the mold closing mode according to the valve core position information, the controller also controls the mold opening oil replenishing valve to be in an energized state to connect the B port of the one-way main valve and the mold opening cavity.

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

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

[0031] When the controller determines that the safety door is open based on the detection result, if the controller determines that the mold shifting cylinder assembly 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 is abnormal.

[0032] In an optional 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 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 with the oil return tank.

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

[0036] A pressure sensor is disposed in the mold clamping cavity and is used to detect pressure information of the mold clamping cavity and send it to the controller;

[0037] When the controller determines that the pressure of the mold cavity 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 is overpressured.

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

[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 mold closing control module and the controller for controlling the mold shifting proportional valve to enter the mold closing mode, the on / off connection between the mold closing control module and the controller is controlled by the first safety switch, that is, if the mold closing control module and the controller want to establish communication, the first safety switch must be in the on state. Among them, since the control of the mold closing mode of the mold shifting proportional valve by the mold closing control module depends on the mold closing signal continuously sent by the controller, that is to say, as long as the controller stops providing the mold closing signal to the mold closing control module, the mold closing control module immediately stops the mold closing control. Therefore, when the safety door is open, the first safety switch is disconnected, which will inevitably cause the mold closing control module to be disconnected from the controller, so that the mold closing control module will not receive the mold closing signal continuously sent by the controller, and then the mold shifting cylinder assembly will not be able to perform the mold closing operation, so that the movable mold plate driven by the mold shifting cylinder assembly in the injection molding machine is in an open mold state, thereby improving the safety and reliability of the injection molding machine. Moreover, compared with the solution in the related art that avoids safety accidents by adding a safety valve in the oil circuit, it can be seen that the present invention does not need to add a safety valve and can also avoid safety accidents. Therefore, the present invention can also reduce the cost generated by adding a safety valve.

[0041] On the other hand, by configuring the mold shifting proportional valve with a mold closing control module and a mold opening control module that are separated from each other, the mold closing mode and the mold opening mode of the mold shifting proportional valve will not interfere with each other, and the disconnection of the mold closing control module from the controller will not affect the connection between the mold opening control module and the controller. The mold opening control module can still communicate with the controller, thereby realizing that the mold shifting 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 A schematic structural diagram of a safety control system for an injection molding machine provided by the present invention;

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

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

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

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

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

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

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

[0050] Fig. 9 This is a schematic structural diagram of another injection molding machine safety control system 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 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-mold closing oil return 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

[0053] 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.

[0054] See also Figure 1 , Figure 1 This is a structural schematic diagram of an injection molding machine safety control system provided by the present invention. The injection molding machine safety 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 first safety switch 3, a mold closing control module 21, a mold opening control module 22, a mold shifting cylinder assembly 9 and a controller.

[0055] 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 .

[0056] 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.

[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 the scenario where the mold closing operation needs to be performed, the safety door 4 needs to be closed to put the first safety switch 3 in the on state, realize the connection between the controller and the mold closing control module 21, and then the controller can send a continuous mold closing signal to the mold closing control module 21. After receiving the continuous mold closing control signal, the mold closing control module 21 controls the mold shifting proportional valve 2 to enter the mold closing mode according to the mold closing control signal, so that the A port of the mold shifting proportional valve 2 is connected to the P port, and the B port is connected to the T port. Based on this, when the hydraulic 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 chamber, the spring at the A port will be pushed open, so that the A port and the B port of the one-way main valve 11 are connected. Therefore, the hydraulic oil will flow out of the port A of the one-way main valve 11 to the port B, and then flow through the ports P and A of the mold shifting proportional valve 2 in sequence to enter the mold closing cavity 92 of the mold shifting cylinder assembly 9, and then flow out from the mold opening cavity 91 to the oil return tank 8 through the ports B and T of the mold shifting proportional valve 2. In this process, the pressure of the mold closing cavity 92 is greater than the pressure of the mold opening cavity 91, so the mold shifting piston rod 93 set in the mold closing cavity 92 moves toward the direction of the mold opening cavity 91, thereby driving the movable mold plate connected to the mold shifting piston rod 93 to move toward the direction of the static mold plate, thereby realizing the mold closing operation.

[0067] However, when the safety door 4 is open, the safety door 4 will always trigger the first safety switch 3 to be in the disconnected state, so the connection between the mold closing control module 21 and the controller is also disconnected. It can be seen that the mold closing control module 21 fails to receive the mold closing signal continuously sent by the controller, 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 hydraulic 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 hydraulic oil cannot enter the mold closing cavity 92, and thus the mold closing operation cannot be performed. Furthermore, even if a small amount of hydraulic 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 hydraulic oil cannot return to the oil return tank 8, and thus the mold closing operation cannot be performed.

[0068] It can be seen that the injection molding machine safety control system provided by the present invention can improve the safety and reliability of the injection molding machine, and does not need to add a safety valve to avoid safety accidents, and can also reduce the cost generated by adding a safety valve.

[0069] In the scenario where the mold opening operation needs to be performed, the opening and closing state of the safety door 4 can be ignored, because the mold opening operation will not cause the risk of the human body being clamped by the moving mold plate and the static mold plate, 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 shifting proportional valve 2 to enter the mold opening mode according to the mold opening control signal, so that the A port of the mold shifting proportional valve 2 is connected to the T port, and the B port is connected to the P port. Based on this, when the hydraulic 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 chamber, the spring at the A port will be pushed open, so that the A port and the B port of the one-way main valve 11 are connected. Therefore, the hydraulic oil will flow out of the port A to the port B of the one-way main valve 11, and flow through the ports P and B of the mold shifting proportional valve 2 in sequence to enter the mold opening cavity 91 of the mold shifting cylinder assembly 9, and then flow out of the mold closing cavity 92 to the oil return tank 8 through the ports A and T of the mold shifting proportional valve 2. In 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 set in the mold closing cavity 92 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.

[0070] As a result, the mold closing mode and mold opening mode of the mold shifting proportional valve 2 do not interfere with each other, and the disconnection of the mold closing control module 21 and 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.

[0071] In some embodiments, in order to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add a layer of safety mechanism, that is, when the controller determines that the safety door 4 is open according to the above-mentioned detection results, the controller can also issue an alarm message for indicating that the mold shifting cylinder assembly 9 is prohibited from performing the mold closing operation, thereby reminding relevant personnel not to input the mold closing instruction to the injection molding machine, which can better improve the safety of use or maintenance of the injection molding machine when the safety door 4 is open.

[0072] In some embodiments, in order to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add a layer of safety mechanism, that is, Figure 2 , Figure 2This is a structural schematic 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 also include a mold closing oil return component connected between the T-port of the mold shifting proportional valve 2 and the oil return tank 8: the mold closing oil return component 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 status 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 shifting proportional valve 2, the A port is connected to the pilot cavity of the mold closing oil return valve 7, and the power supply input end 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 shifting 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 disconnected state, and the oil return passage between the mold shifting proportional valve 2 and the oil return tank 8 is in a disconnected state.

[0077] 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 mold closing oil return pilot valve 71 is always in the power-off state, so that 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 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 hydraulic oil discharged from the mold opening cavity 91 must be larger 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 reflux tank, in order 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 not connected, the hydraulic 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, and the mold closing operation cannot be performed without oil return. This can further improve the safety of the use or maintenance of the injection molding machine when the safety door 4 is open.

[0079] In some embodiments, in order to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add a layer of safety mechanism, that is, Figure 3 , Figure 3This is a structural schematic 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 also include:

[0080] 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.

[0081] When the safety door 4 is open, 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 in a disconnected state, and the mold clamping cavity 92 and the main pressure oil circuit 1 are in a disconnected state.

[0082] Therefore, when the safety door 4 is open, 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 in from the A port of the one-way pilot valve 111 will flow from the P port of the one-way pilot valve 111 into the pilot chamber of the one-way main valve 11, and the pressure area of ​​the pilot chamber of the one-way main valve 11 is larger than the pressure area of ​​the A port of the one-way main valve 11, and the pilot chamber of the one-way main valve 11 is also provided with a spring for applying pressure to the A port, so it can be ensured that the pressure of the pilot chamber of the one-way main valve 11 is greater than the pressure of the A port of the one-way main valve 11, thereby making the A port of the one-way main valve 11 and the B port of the one-way main valve 11 in a non-connected state.

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

[0084] In some embodiments, in order to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can 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 also include:

[0085] 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.

[0086] When the controller determines that the safety door 4 is open according to the above detection results, 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, or the injection molding machine is controlled to stop running and an alarm message is issued to indicate that the mold shifting proportional valve 2 is abnormal.

[0087] 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.

[0088] 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. When the controller determines that the safety door 4 is open according to the above detection results, 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.

[0089] In addition, the controller can also issue an alarm message for indicating an abnormality of the mold shift proportional valve 2, so as to prompt relevant personnel to perform fault detection or maintenance on the mold shift proportional valve 2. Because when the safety door 4 is open, the communication between the controller and the mold closing control module 21 is disconnected, and the mold closing control module 21 cannot control the mold shift proportional valve 2 to enter the mold closing mode, so it is possible that the mold shift proportional valve 2 has a fault, for example, the mold shift proportional valve 2 has a stuck valve phenomenon, and the valve core is stuck at the position where the A port of the mold shift proportional valve 2 can be connected to the P port. Therefore, in order to ensure the safety and stability of the subsequent use of the injection molding machine, an alarm message indicating an abnormality of the mold shift proportional valve 2 can also be issued in time to avoid affecting the subsequent operation of the injection molding machine.

[0090] In some embodiments, based on the previous embodiment, in order to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add a layer of safety mechanism, that is, refer to Figure 4 , Figure 4 This is a structural schematic 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 also include:

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

[0092] When the controller determines that the safety door 4 is open according to the above detection results, 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 controller also controls the mold opening oil replenishing valve 12 to be in an energized state to connect the B port of the one-way main valve 11 and the mold opening cavity 91.

[0093] Therefore, when the controller determines that the safety door 4 is open according to the detection result, if the controller determines that the mold shifting proportional valve 2 is in the mold closing mode according to the valve core position information, it may indicate that the mold shifting proportional valve 2 is stuck, and the valve core is stuck at a position where the A port and the P port of the mold shifting proportional valve 2 can be connected. Therefore, in order to further reduce the risk, the controller can also control the mold opening oil replenishing valve 12 to be in an energized state, and the P port and the B port of the mold opening oil replenishing valve 12 are connected after being energized, so that even if hydraulic oil flows out of the B port of the one-way main valve 11, the outflowing hydraulic oil will flow from two branches, one of which is the oil circuit where the P port and the A port of the mold shifting 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, so that the hydraulic oil will enter the mold closing cavity 92 and the mold opening cavity 91 respectively, so that the mold closing cavity 92 and the mold opening cavity 91 are connected through the hydraulic oil, and the pressure of the two is consistent, so the mold closing operation cannot be performed.

[0094] In addition, since the mold closing cavity 92 is a rod cavity, its area is smaller than the area of ​​the mold opening cavity 91 which is a rodless cavity. Therefore, when the pressures of the mold closing cavity 92 and the mold opening cavity 91 are consistent, since the area of ​​the mold opening cavity 91 is larger than that of the mold closing cavity 92, the mold shifting cylinder assembly 9 can only perform the mold opening operation but not the mold closing operation.

[0095] Furthermore, when the valve core of the mold shifting proportional valve 2 is stuck in the connection between the P port and the B port of the mold shifting proportional valve 2, regardless of whether the mold opening oil replenishing valve 12 is energized, the hydraulic oil will flow into the mold opening cavity 91 and flow out to the return oil tank 8 through the mold closing cavity 92. Therefore, the mold shifting cylinder assembly 9 can only perform the mold opening operation and will not perform the mold closing operation.

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

[0097] In some embodiments, in order to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add a layer of safety mechanism, that is, Figure 5 , Figure 5 This is a structural schematic 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 mold shifting piston rod 93 is provided in the mold clamping cavity 92; and a mold shifting position detection module 94 is provided on the mold shifting piston rod 93.

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

[0099] When the controller determines that the safety door 4 is open according to the above detection results, if the controller determines that the mold shifting cylinder assembly 9 performs a mold closing 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 is issued to indicate that the mold shifting cylinder assembly 9 is abnormal.

[0100] Since the mold shifting position detection module 94 can detect the mold position information of the movable mold plate in real time, 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.

[0101] Therefore, in the absence of mold closing control, 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.

[0102] 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.

[0103] In some embodiments, in order to further improve the safety of the injection molding machine, the injection molding machine safety control system provided by the present invention can add a layer of safety mechanism, that is, Figure 6 , Figure 6This is a structural schematic 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 also include:

[0104] The proportional pressure valve 13 is connected between the 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 open according to the above detection result, the controller controls the proportional pressure valve 13 to be in a conducting state to connect the B port of the one-way main valve 11 with the oil return tank 8 .

[0106] Therefore, in order to ensure that there is no mold closing operation when the safety door 4 is open, the controller can control the proportional pressure valve 13 to be in a conducting state, for example, setting the pressure of the proportional pressure valve 13 to 0, so that the hydraulic oil of any pressure at the B port of the one-way main valve 11 can be directly discharged from the proportional pressure valve 13 back to the reflux tank without passing through the mold shifting proportional valve 2, thereby making it impossible for the injection molding machine to perform the mold closing operation, which can further improve the safety of the use or maintenance of the injection molding machine when the safety door 4 is open.

[0107] In some embodiments, in order to prevent the mold from being damaged by excessive pressure in the mold cavity 92, or causing defects in the molded part or equipment failure, the injection molding machine safety control system provided by the present invention can add a layer of safety mechanism, that is, refer to Figure 7 , Figure 7 This is a structural schematic 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 also include:

[0108] 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.

[0109] 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 indicating that the mold shifting cylinder assembly 9 is overpressured.

[0110] Thus, it is possible to avoid the mold cavity 92 continuing to work under overpressure, which may cause damage to the mold, damage to the molded part, or equipment failure, which is beneficial to extending the service life of the injection molding machine safety control system and reducing maintenance costs.

[0111] It is worth noting that one or more of the security mechanisms in the above multiple embodiments provided by the present invention can be combined with each other to achieve a better security control effect. As an example, all of the above security mechanisms can be combined. Figure 8 , Figure 8This is a schematic diagram of the structure of another injection molding machine safety control system provided by the present invention. It can be seen that the injection molding machine safety control system at this time may include all the devices, functions and technical effects mentioned in the above embodiments. Figure 8 The technical principles and technical effects of the injection molding machine safety control system shown can be referred to the relevant records above and will not be elaborated here.

[0112] In some embodiments, to realize the injection molding machine control safety system with the function of rapid mold opening and closing, please refer to Fig. 9 , Fig. 9 : is a structural schematic 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 also include:

[0113] The express valve 6 has its port A connected between the port T of the mold shifting proportional valve 2 and the port P of the mold closing oil return pilot valve 71, and its port B connected to the mold opening cavity 91;

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

[0115] When the express pilot valve 61 is powered off, its A port is connected to the P port, and its B port is connected to the T port; when the express pilot valve 61 is powered on, its A port is connected to the T port, and its B port is connected to the P port.

[0116] The relevant principles of using the express pilot valve 61 to realize the rapid mold closing and opening of the injection molding machine can be found in the relevant technology and will not be elaborated here.

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

[0118] For the technical principles of implementing safety control for the injection molding machine, please refer to the relevant records in the embodiments of the safety control system for the injection molding machine, which will not be elaborated here.

[0119] 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 safety control system for an injection molding machine, characterized in that: It includes a one-way main valve, a mold shifting proportional valve, a first safety switch, a mold closing control module, a mold opening control module, a mold shifting cylinder 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 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 first safety switch is used to detect the open and closed state of the safety door of the injection molding machine and send the corresponding detection result to the controller; The mold closing control module is connected to the controller via the first safety switch, and is used to control the mold shifting proportional valve to enter a mold closing mode according to the mold closing signal continuously sent by the controller, so as to control the mold shifting cylinder assembly to perform a mold closing operation; The mold opening control module is separately arranged from the mold closing control module and connected to the controller, and is used to control the mold shifting proportional valve 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 to perform the mold opening operation; When the safety door is open, the first safety switch is disconnected, the mold closing control module is disconnected from the controller, and the mold closing control module does not receive a continuous mold closing control signal, so that the mold moving cylinder assembly does not perform a mold closing operation.

2. The injection molding machine safety control system according to claim 1, characterized in that: 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 shifting cylinder assembly is prohibited from performing a mold closing operation.

3. The injection molding machine safety control system according to claim 1, characterized in that: It also includes a mold closing oil return assembly connected between the T port of the mold shifting proportional valve and the oil return tank: the mold closing oil return assembly includes a second safety switch, a mold closing oil return pilot valve and a mold closing oil return valve; The second safety switch is used to detect the opening and closing status of the safety door; The P port of the mold closing oil return pilot valve is connected to the T port of the mold shifting proportional valve, the A port is connected to the pilot cavity of the mold closing oil return valve, and the power supply input end of the mold closing oil return pilot valve is connected to the power supply through the second safety switch; 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; When the safety door is open, the second safety switch is disconnected, the mold closing oil return pilot valve is in a power-off state, the A port and the B port of the mold closing oil return valve are in a disconnected state, and the oil return passage between the mold shifting proportional valve and the oil return tank is in a disconnected state.

4. The injection molding machine safety 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; When the safety door is open, 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 disconnected state, and the mold clamping cavity and the main pressure oil circuit are in a disconnected state.

5. The injection molding machine safety control system according to claim 1, characterized in that: Also includes: A valve core position detection module is provided in the mold shifting proportional valve, and is used to detect valve core position information of a main valve core of the mold shifting proportional valve, and send the information to the controller; When the controller determines that the safety door is open based on the detection result, if the controller determines that the mold shifting proportional valve is in the mold closing mode based on the valve core 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 proportional valve is abnormal.

6. The injection molding machine safety control system according to claim 5, characterized in that: Also includes: A mold opening oil replenishing valve, wherein the 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; When the controller determines that the safety door is open according to the detection result, if the controller determines that the mold shifting proportional valve is in the mold closing mode according to the valve core position information, the controller also controls the mold opening oil replenishing valve to be in an energized state to connect the B port of the one-way main valve and the mold opening cavity.

7. The injection molding machine safety control system according to claim 1, characterized in that: A mold shifting piston rod is provided in the mold clamping cavity; a mold shifting position detection module is provided on the mold shifting piston rod; The mold shifting position detection module is used to detect the template position information of the movable template in the injection molding machine and send it to the controller; When the controller determines that the safety door is open based on the detection result, if the controller determines that the mold shifting cylinder assembly 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 is abnormal.

8. The injection molding machine safety control system according to any one of claims 1 to 7, 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 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 with the oil return tank.

9. The injection molding machine safety control system according to claim 1, characterized in that: Also includes: A pressure sensor is disposed in the mold clamping cavity and is used to detect pressure information of the mold clamping cavity and send it to the controller; When the controller determines that the pressure of the mold cavity 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 is overpressured.

10. An injection molding machine, characterized in that: The invention comprises the injection molding machine safety control system according to any one of claims 1 to 9.

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