Safety exhaust valve group for a blow molding machine

Abstract

The application relates to a blow molding machine safety exhaust valve group, which comprises a gas source air inlet pipeline, a normally open electromagnetic valve, a normally closed electromagnetic valve, a blow molding machine gas end, an exhaust passage and a safety door linkage device. The gas source air inlet pipeline, the blow molding machine gas end and the exhaust passage are connected through a tee pipe. The normally closed electromagnetic valve is connected in series between the gas source air inlet pipeline and the blow molding machine gas end. The exhaust passage is located between the normally closed electromagnetic valve and the blow molding machine gas end. The normally open electromagnetic valve is connected in series on the exhaust passage. The safety door linkage device is electrically connected with the normally open electromagnetic valve and the normally closed electromagnetic valve. The blow molding machine safety exhaust valve group and the control method can realize stable air inlet during normal production, open the safety door, realize quick air cut-off and exhaust when the equipment is abnormal, power-off or the emergency stop button is pressed, improve the operation safety of the blow molding machine, and guarantee production and personnel safety.

Description

Technical Field

[0001] This application relates to the field of blow molding machine equipment technology, and in particular to a safety exhaust valve assembly for a blow molding machine. Background Technology

[0002] In the production process of blow molding machines, the pneumatic system, as the core unit for drive and execution, directly determines the overall operating efficiency and reliability of the machine due to the stability and safety of its operation. Traditional pneumatic control solutions for blow molding machines often exhibit slow response and insufficient judgment accuracy when faced with emergencies such as sudden opening of safety doors, abnormal air pressure fluctuations, or equipment overload. Especially in scenarios requiring immediate intervention, such as safety door opening, if the system cannot quickly cut off the main air intake and completely release residual pressure in the circuit within milliseconds, the mold may experience abnormal closure or collision under pressure, leading to cavity damage, cooling pipe rupture, and semi-finished products suffering from flash and uneven wall thickness due to pressure runaway, resulting in batch quality scrap. Furthermore, existing pneumatic modules lack coordination, resulting in low system integration and difficulty in meeting the high-efficiency and safe production requirements of blow molding machines. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide a safety exhaust valve assembly for a blow molding machine, which can be linked with a safety gate to improve the operational safety of the blow molding machine and ensure production and personnel safety.

[0004] To achieve the above objectives, this application adopts the following technical solution: A safety exhaust valve assembly for a blow molding machine includes an air source inlet pipe, a normally open solenoid valve, a normally closed solenoid valve, an air supply end for the blow molding machine, an exhaust passage, and a safety door linkage device, specifically including: The air source inlet pipe, the air supply end of the blow molding machine, and the exhaust passage are connected by a T-junction. The normally closed solenoid valve is connected in series between the air source inlet pipe and the air supply end of the blow molding machine. The exhaust passage is located between the normally closed solenoid valve and the air supply end of the blow molding machine. The normally open solenoid valve is connected in series on the exhaust passage. The safety door linkage device is electrically connected to the normally open solenoid valve and the normally closed solenoid valve.

[0005] In some embodiments, the air inlet pipe is connected to an external air source, and the air supply end for the blow molding machine is connected to the blow molding machine.

[0006] In some embodiments, the safety door linkage device is mechanically linked to the safety door of the blow molding machine. The safety door linkage device includes a limit switch that can be triggered when the safety door is opened or closed, and at least one relay electrically connected to the limit switch. At least one of the relays is connected in series between the normally open solenoid valve and the power supply circuit and the normally closed solenoid valve and the power supply circuit.

[0007] In some embodiments, when the safety door of the blow molding machine is in the closed state, the safety door linkage device is electrically connected to the normally open solenoid valve and the normally closed solenoid valve respectively. The normally closed solenoid valve is in the open state, and a passage is formed between the external air source, the air source inlet pipe and the air-using end of the blow molding machine. The normally open solenoid valve is in the closed state, and the air source inlet pipe and the exhaust passage are disconnected. When the safety door of the blow molding machine is in the open state, the safety door linkage device is disconnected from the normally open solenoid valve and the normally closed solenoid valve respectively. The normally closed solenoid valve is in the closed state, and the air source inlet pipe is disconnected from the air supply end of the blow molding machine. The normally open solenoid valve is in the open state, and a passage is formed between the air supply end of the blow molding machine and the exhaust passage.

[0008] In some embodiments, the safety door linkage device is mechanically linked to an emergency stop button, and the safety door linkage device is a limit switch or relay that can be passively triggered when the emergency stop button is pressed.

[0009] Compared with the prior art, the beneficial effects of this application are as follows: The gas pipeline of this application is linked with the safety door. When the safety door is opened, the gas can be quickly cut off and the gas can be exhausted, effectively avoiding safety hazards such as mold damage and product splashing, protecting equipment and operators, and meeting the safety production requirements of blow molding workshops. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of a safety exhaust valve assembly for a blow molding machine, provided in an embodiment of this application.

[0011] Figure 2 A schematic diagram of the control circuit for the safety door linkage control unit provided in the embodiments of this application.

[0012] Among them, 100 is the safety exhaust valve group of the blow molding machine; 10 is the air source inlet pipe; 20 is the normally open solenoid valve; 30 is the normally closed solenoid valve; 40 is the air supply end of the blow molding machine; 50 is the exhaust passage; 60 is the safety door linkage device; 601 is the limit switch; and 602 is the relay. Detailed Implementation

[0013] To illustrate the technical content, structural features, achieved objectives, and effects of the invention in detail, the technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. In the following description, for illustrative purposes, numerous specific details are set forth to provide a detailed description of various exemplary embodiments or implementations of the invention. However, various exemplary embodiments may also be implemented without these specific details or in one or more equivalent arrangements. Furthermore, the various exemplary embodiments may differ, but are not necessarily exclusive. For example, the specific shape, construction, and characteristics of the exemplary embodiments may be used or implemented in another exemplary embodiment without departing from the inventive concept.

[0014] This invention relates to a safety exhaust valve assembly for a blow molding machine. By using normally open and normally closed solenoid valves, it achieves stable air intake during normal production and rapid air cut-off and exhaust when the safety door is opened, or in case of equipment malfunction, power failure, or pressing of the emergency stop button, thereby improving the operational safety of the blow molding machine and ensuring the safety of production and personnel.

[0015] See Figures 1-2 A safety exhaust valve assembly 100 for a blow molding machine includes an air source inlet pipe 10, a normally open solenoid valve 20, a normally closed solenoid valve 30, a blow molding machine air supply end 40, an exhaust passage 50, and a safety door linkage device 60. The air source inlet pipe 10, the blow molding machine air supply end 40, and the exhaust passage 50 are connected by a T-junction. The exhaust passage 50 is located between the air source inlet pipe 10 and the blow molding machine air supply end 40, and downstream of the normally closed solenoid valve 30. The normally closed solenoid valve 30 is connected in series between the air source inlet pipe 10 and the blow molding machine air supply end 40. The normally open solenoid valve 20 is located after the normally closed solenoid valve 30 and connected in series with the exhaust passage 50. The safety door linkage device 60 is electrically connected to the normally open solenoid valve 20 and the normally closed solenoid valve 30.

[0016] The safety door linkage device includes one or more limit switches that can be triggered when the safety door is opened or closed, and one or more relays connected in series between the normally open solenoid valve 20 and the power supply circuit, and between the normally closed solenoid valve 30 and the power supply circuit. The limit switches are electrically connected to the relays. When a limit switch is triggered, the relay is energized, and both the normally open and normally closed solenoid valves 20 and 30 are energized; or, when a limit switch is triggered, the relay is de-energized, and both the normally open and normally closed solenoid valves 20 and 30 are de-energized. The limit switches can be installed in the closed position or the open position of the safety door, depending on the actual installation needs of the site.

[0017] In this embodiment, please refer to [link to previous document] for the gas flow direction. Figure 1The arrows indicate that the air source inlet pipe 10 connects to an external air source to supply gas to the pneumatic actuator of the blow molding machine; the normally closed solenoid valve 30 is connected in series with the air source inlet pipe 10, initially closed, remains open when energized, and closes when de-energized to cut off the air source to the air-consuming end 40 of the blow molding machine; the normally open solenoid valve 20 is connected to a branch of the air source inlet pipe 10 and the exhaust passage 50, initially open, remains closed when energized, and opens when de-energized to conduct the exhaust passage; the air-consuming end 40 of the blow molding machine is connected to the air source inlet pipe 10 to receive gas for blow molding operations.

[0018] The safety door linkage device 60 is mechanically linked with the safety door of the blow molding machine. When the safety door is closed and the equipment is working normally, the normally open solenoid valve 20 and the normally closed solenoid valve 30 are energized. When the safety door is opened or the equipment is abnormal, the power supply to the normally open solenoid valve 20 and the normally closed solenoid valve 30 is cut off, and the linkage solenoid valve is activated.

[0019] The working process of the safety exhaust valve of the blow molding machine, which achieves safe air intake and exhaust through the coordinated control of dual solenoid valves, is as follows: When the safety door of the blow molding machine is closed, the safety door linkage device 60 simultaneously supplies power to the normally open solenoid valve 20 and the normally closed solenoid valve 30. The normally closed solenoid valve 30 is energized and turned on, and the external air source supplies air to the air-consuming end 40 of the blow molding machine through the air source inlet pipe 10 to meet the air intake requirements of blow molding (such as mold inflation, product cooling and shaping, cylinder action, etc.). The normally open solenoid valve 20 is energized and kept closed to prevent gas leakage and ensure stable air pressure. When the safety door of the blow molding machine is opened due to maintenance, abnormality, or other reasons, the safety door linkage device 60 simultaneously disconnects the power supply to the normally open solenoid valve 20 and the normally closed solenoid valve 30. The normally closed solenoid valve 30 is de-energized and closes, cutting off the air supply to the air-consuming end 40 of the blow molding machine, and the pneumatic operation of the blow molding machine is interrupted. The normally open solenoid valve 20 is de-energized and opens, and the residual gas in the air-consuming end 40 of the blow molding machine and the pipeline is discharged through the exhaust passage, quickly releasing pressure and preventing safety hazards such as machine malfunction and product flying caused by residual air pressure. When the safety door linkage device 60 restores power to the normally closed solenoid valve 30 and the normally open solenoid valve 20, the air intake of the blow molding machine 40 can be restarted to continue the production process.

[0020] In this embodiment, the safety door linkage device 60 includes a limit switch 601 and a relay 602. The limit switch 601 is installed near the safety door when it is in the closed position, such as on the door frame or wall. When the safety door of the blow molding machine is closed, the limit switch 601 is triggered to send an electrical signal to activate the relay 602, which supplies power to the normally closed solenoid valve 30 and the normally open solenoid valve 20. When the safety door of the blow molding machine is opened, the signal of the limit switch 601 is interrupted, and the relay 602 is de-energized.

[0021] In this embodiment, the normally closed solenoid valve 30 is initially normally closed, conducts when energized, and closes when de-energized; the normally open solenoid valve 20 is initially normally open, closes when energized, and opens when de-energized.

[0022] In this embodiment, the air source inlet pipe 10 is selected from air pipes that are compatible with the air pressure and flow of the blow molding machine and are stably connected to external air sources such as air compressors; the normally open solenoid valve 20 and normally closed solenoid valve 30 are selected according to the working air pressure and voltage parameters of the blow molding machine, and are connected in series to the air inlet pipe and exhaust branch through pipe joints and wires respectively, and are connected to the safety door linkage device 60 and integrated into the pneumatic control system of the blow molding machine.

[0023] In this embodiment, during normal blow molding, the safety door is closed, the limit switch 601 is triggered, the relay 602 is engaged, and the normally open solenoid valve 20 and normally closed solenoid valve 30 are energized. The normally closed solenoid valve 30 is open, allowing the gas source to continuously supply gas to the blow molding mold and forming mechanism, ensuring stable gas pressure during the blow molding process. The normally open solenoid valve 20 is closed, ensuring that the gas is used specifically for production and preventing exhaust leakage. In abnormal situations, the safety door opens (e.g., during personnel maintenance or equipment malfunction alarms), the limit switch 601 resets, the relay 602 is disconnected, and the normally open solenoid valve 20 and normally closed solenoid valve 30 are de-energized. The normally closed solenoid valve 30 instantly cuts off the gas source upon closing, preventing the introduction of new gas from exacerbating the risk. The normally open solenoid valve 20 opens to quickly discharge residual gas from the pipeline and mold, relieving pressure. Once the safety door closes and power is restored, blow molding production can resume, achieving intelligent switching between safety and production processes.

[0024] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope. The scope of protection of the present invention is defined by the appended claims, specification, and their equivalents.

Claims

1. A safety exhaust valve assembly for a blow molding machine, comprising an air source inlet pipe, a normally open solenoid valve, a normally closed solenoid valve, an air supply end for the blow molding machine, an exhaust passage, and a safety door linkage device, characterized in that: The air source inlet pipe, the air supply end of the blow molding machine, and the exhaust passage are connected by a T-junction. The normally closed solenoid valve is connected in series between the air source inlet pipe and the air supply end of the blow molding machine. The exhaust passage is located between the normally closed solenoid valve and the air supply end of the blow molding machine. The normally open solenoid valve is connected in series on the exhaust passage. The safety door linkage device is electrically connected to the normally open solenoid valve and the normally closed solenoid valve.

2. The safety exhaust valve assembly for a blow molding machine according to claim 1, characterized in that, The air inlet pipe is connected to an external air source, and the air supply end for the blow molding machine is connected to the blow molding machine.

3. The safety exhaust valve assembly for a blow molding machine according to claim 2, characterized in that, The safety door linkage device is mechanically linked with the safety door of the blow molding machine. The safety door linkage device includes a limit switch that can be triggered when the safety door is opened or closed, and at least one relay electrically connected to the limit switch. At least one of the relays is connected in series between the normally open solenoid valve and the power supply circuit and the normally closed solenoid valve and the power supply circuit.

4. The safety exhaust valve assembly for a blow molding machine according to claim 3, characterized in that, When the safety door of the blow molding machine is closed, the safety door linkage device is electrically connected to the normally open solenoid valve and the normally closed solenoid valve respectively. The normally closed solenoid valve is open, and a passage is formed between the external air source, the air source inlet pipe and the air-using end of the blow molding machine. The normally open solenoid valve is closed, and the air source inlet pipe and the exhaust passage are disconnected. When the safety door of the blow molding machine is in the open state, the safety door linkage device is disconnected from the normally open solenoid valve and the normally closed solenoid valve respectively. The normally closed solenoid valve is in the closed state, and the air source inlet pipe is disconnected from the air supply end of the blow molding machine. The normally open solenoid valve is in the open state, and a passage is formed between the air supply end of the blow molding machine and the exhaust passage.

5. The safety exhaust valve assembly for a blow molding machine according to claim 3, characterized in that, The safety door linkage device is mechanically linked to an emergency stop button. The safety door linkage device is a limit switch or relay that can be passively triggered when the emergency stop button is pressed.

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