High-back-pressure safety protection and automatic alarm device for filter press
Through the combination of PLC programmable controller and electrical contact pressure gauge, automatic monitoring and alarm of the return pressure of the hydraulic cylinder of the filter press is realized, solving the problem of the return pressure of the hydraulic cylinder exceeding the limit, ensuring the safe operation of the equipment and personnel safety.
Patent Information
- Application Number
- CN202320716902.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-04-04
- Publication Date
- 2025-08-01
- Estimated Expiration
- 2033-04-04
AI Technical Summary
During the use of the filter press, when the hydraulic cylinder return pressure exceeds the safety pressure, it is easy to cause damage to hydraulic accessories and safety accidents. The existing technology lacks effective safety protection and automatic alarm mechanism.
The PLC programmable controller is used to combine the electrical contact pressure gauge and alarm device. By setting the upper and lower pressure contacts, the hydraulic cylinder return pressure is automatically monitored and alarmed to ensure the safe operation of the hydraulic system.
It realizes automatic alarm and safety protection when the hydraulic cylinder return pressure exceeds the safety pressure, avoids damage to hydraulic system accessories and personnel injury, and ensures the safe operation and economic benefits of the equipment.
Smart Images
Figure CN223170411U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the field of filter press equipment in the solid-liquid separation industry, and relates to a high back-pressure safety protection and automatic alarm device for a filter press. Background Technique
[0002] A filter press is a mechanical device that uses a special filter medium to apply pressure to the filtered material so that the liquid seeps out. It is a commonly used solid-liquid separation device. Solid-liquid separation is an important link in sewage treatment, and the filter press plays an important role in the sewage treatment process.
[0003] The filter press mainly consists of a hydraulic system, an electrical control system, a double-acting hydraulic cylinder part, a transmission system, a filter plate part, a frame part, etc. The filter press needs to be used in cooperation with a feed pump, and the two devices are connected by a pipeline. After the filter press completes the equipment pressure holding through the hydraulic system, a cavity sealed around is formed inside the filter plate of the press. The feed pump pumps the material to be filtered into the cavity formed by the filter plate of the filter press and provides the required filtration pressure. Under the action of the filtration pressure, the water in the material will pass through the filter medium and be discharged, and the solid substances are intercepted on the other side of the filter medium, achieving the purpose of solid-liquid separation.
[0004] During the working process of the filter press, parameters such as feed pressure, hydraulic cylinder pressure, and hydraulic cylinder back-pressure are involved. The feed pressure refers to the filtration pressure provided by the feed pump; the hydraulic cylinder pressure refers to the pressure range set by the hydraulic system, including hydraulic low pressure and hydraulic high pressure; the hydraulic cylinder back-pressure refers to the pressure presented in the rear cavity of the hydraulic cylinder under the feed pressure of the feed pump. In the actual use of the filter press, sometimes the on-site configured feed pump does not match the required feed pressure of the filter press or the operator mistakenly adjusts the hydraulic cylinder pressure, which will cause the hydraulic cylinder back-pressure to exceed the safety pressure of the hydraulic cylinder, resulting in damage to hydraulic accessories or safety accidents, thereby causing harm to on-site operators or losses to economic benefits. Summary of the Invention
[0005] The purpose of the utility model is to solve the deficiencies in the above background technology, and provide a high back-pressure safety protection and automatic alarm device for a filter press, which can provide safety protection and automatic alarm functions when the hydraulic cylinder back-pressure exceeds the safety pressure. It includes: a PLC programmable controller, an electric contact pressure gauge one and an electric contact pressure gauge two, a fault indicator light and a buzzer alarm, a feed pump switch and a hydraulic pump switch of the hydraulic system. The PLC programmable controller is connected to the electric contact pressure gauge one, the electric contact pressure gauge one is connected to the hydraulic pump switch of the hydraulic system, the PLC programmable controller is connected to the electric contact pressure gauge two, the electric contact pressure gauge two is connected to the feed pump switch, and the PLC programmable controller is connected to the fault indicator light and the buzzer alarm.
[0006] The electric contact pressure gauge 1 is provided with a lower pressure limit contact and an upper pressure limit contact. The lower pressure limit contact controls the lower limit pressure for the hydraulic cylinder of the hydraulic system to be tightened, and the upper pressure limit contact controls the upper limit pressure for the hydraulic cylinder of the hydraulic system to be tightened. The electric contact pressure gauge 2 is provided with an upper pressure limit contact and a lower pressure limit contact. The lower pressure limit contact is connected to the feed pump switch to control the backpressure of the hydraulic cylinder.
[0007] A high backpressure safety protection and automatic alarm device for a filter press provided by the present invention can achieve the effect of interlocking safety between the backpressure of the hydraulic cylinder and the start-stop device of the feed pump. The entire working process of the filter press is uniformly controlled by a PLC programmable controller, which controls the hydraulic pressing process, the feeding process, and the discharging process of the filter press. According to the PLC programmable controller, the start switch of the hydraulic pump of the filter press hydraulic system is automatically controlled to be turned on. After the hydraulic cylinder pressure reaches the upper pressure limit contact set by the electric contact pressure gauge 1, the electric contact pressure gauge 1 provides a switch signal, and according to the PLC programmable controller, the hydraulic pump is controlled to be turned off. If the hydraulic cylinder pressure of the hydraulic system drops to the lower pressure limit contact set by the electric contact pressure gauge 1, the electric contact pressure gauge 1 provides a switch signal, and according to the PLC programmable controller, the hydraulic pump is controlled to be started. After the hydraulic cylinder pressure reaches the upper pressure limit of the electric contact pressure gauge 1, the electric contact pressure gauge 1 provides a switch signal to turn off the hydraulic pump, and the filter press enters the hydraulic pressure holding state. After the filter press enters the pressure holding state, the PLC programmable controller controls the start of the feed pump to start the feeding process, and the feeding process is controlled by the feeding time. After the feeding is completed, the PLC programmable controller controls the shutdown of the feed pump, starts the hydraulic pump of the hydraulic system, and releases the hydraulic pressing to complete the discharging process. During the operation of the filter press, if the feeding pressure of the on-site equipped feed pump exceeds the required feeding pressure of the filter press, resulting in the backpressure of the hydraulic cylinder exceeding the safety pressure of the hydraulic cylinder and exceeding the lower pressure limit contact set by the electric contact pressure gauge 2, the electric contact pressure gauge 2 provides a switch signal, and according to the PLC programmable controller, the feed pump is controlled to be turned off. At the same time, the fault indicator light flashes, and the buzzer alarm sounds. After the operator sees or hears the alarm signal, the operator quickly conducts a fault check. After the fault is eliminated, the system is restarted. The high backpressure safety protection and automatic alarm device of the filter press is controlled by the PLC programmable controller, and uses the switch signal of the electric contact pressure gauge to ensure that no safety accident will occur and avoid high-pressure damage to the accessories of the hydraulic system after the backpressure of the filter press hydraulic cylinder exceeds the safety pressure of the hydraulic cylinder, protecting the lives of on-site personnel and reducing economic losses. Brief Description of the Drawings
[0008] Figure 1 is an electrical control schematic diagram of the "high backpressure safety protection and automatic alarm device for a filter press" of the present invention.
[0009] In the figure, 1. is a PLC programmable controller, 2. is a power switch, 3. is the lower pressure contact of the electric contact pressure gauge II, 4. is the upper pressure contact of the electric contact pressure gauge II, 5. is a fault indicator light, 6. is a buzzer alarm, 7. is a feed pump switch, 8. is a hydraulic pump switch of the hydraulic system, 9. is the upper pressure contact of the electric contact pressure gauge I, 10. is the lower pressure contact of the electric contact pressure gauge I. Detailed implementation mode
[0010] The present utility model provides a high backpressure safety protection and automatic alarm device for a filter press, and the electrical control schematic diagram is shown in Figure 1. This device is automatically controlled by the PLC programmable controller 1, and an electric contact pressure gauge I and an electric contact pressure gauge II are set. Both the electric contact pressure gauge I and the electric contact pressure gauge II are installed in the rear cavity of the double-acting hydraulic cylinder of the filter press hydraulic system. The electric contact pressure gauge I is provided with an upper pressure contact 9 and a lower pressure contact 10, and the electric contact pressure gauge II is provided with an upper pressure contact 4 and a lower pressure contact 3. The upper pressure contact 9 and the lower pressure contact 10 of the electric contact pressure gauge I and the lower pressure contact 3 of the electric contact pressure gauge II are all connected to the PLC programmable controller 1. A fault indicator light 5 is set and connected to the PLC programmable controller 1. A buzzer alarm 6 is set and connected to the PLC programmable controller 1. A hydraulic pump switch 8 of the hydraulic system is set and connected to the upper pressure contact 9 and the lower pressure contact 10 of the electric contact pressure gauge I. The lower pressure contact 3 of the electric contact pressure gauge II is set and connected to the feed pump switch 7. A power switch 2 is set and connected to the PLC programmable controller 1.
[0011] During the working process of the filter press, the overall equipment electrical control is completely automatically controlled and operated by the PLC programmable controller 1. After turning on the power switch 2, according to the instruction of the PLC programmable controller 1, the hydraulic pump switch 8 of the hydraulic system is started, and the hydraulic system starts to operate. The piston rod of the hydraulic cylinder extends to press the filter plate tightly. When the pressing pressure of the hydraulic cylinder reaches the upper pressure contact 9 of the electric contact pressure gauge I, an instruction is issued by the PLC programmable controller 1 to turn off the hydraulic pump switch 8 of the hydraulic system. At this time, a cavity with a sealed periphery is formed inside the filter plate of the filter press, and the hydraulic system enters the pressure-holding state. If there is pressure relief in the filter press hydraulic system, when the pressing pressure of the hydraulic system drops to the lower pressure contact 10 of the electric contact pressure gauge I, an instruction is issued by the PLC programmable controller 1 to start the hydraulic pump switch 8 of the hydraulic system, and the hydraulic system starts to work. The pressing force of the hydraulic system rises to keep the pressing pressure of the hydraulic system within the range, and the pressing process is completed; an instruction is issued by the PLC programmable controller 1 to start the feed pump switch 7 to start feeding. The feeding time is controlled by time. After the feeding is completed, an instruction is issued by the PLC programmable controller 1 to turn off the feed pump switch 7 to complete the feeding process; an instruction is issued by the programmable controller 1 to turn on the hydraulic pump switch 8 of the hydraulic system, and the hydraulic system starts to work to loosen the filter press filter plate and start discharging to complete the discharging process.
[0012] During the operation of the filter press, if there are faults such as the feeding pressure of the feeding pump equipped with the filter press exceeding the specified feeding pressure, resulting in the backpressure of the hydraulic cylinder exceeding the safety pressure of the hydraulic cylinder, the lower pressure limit contact 3 of the pressure gauge of the normally open contact is triggered. The PLC programmable controller 1 issues an instruction to close the switch 7 of the feeding pump. At the same time, the fault indicator light 5 starts to flash, and the buzzer alarm 6 immediately sounds an alarm. After receiving the alarm information from the fault indicator light and the buzzer alarm, the on-site operator quickly conducts a fault check and troubleshoots the fault to avoid safety accidents, economic losses, and ensure the safe operation of the filter press and the safety of the operator's life.
Claims
1. A high backpressure safety protection and automatic alarm device for a filter press, comprising: PLC programmable controller, electric contact pressure gauge 1 and electric contact pressure gauge 2, fault indicator light and buzzer alarm, feed pump switch and hydraulic pump switch of the hydraulic system, characterized in that: the PLC programmable controller is connected to the electric contact pressure gauge 1, the electric contact pressure gauge 1 is connected to the hydraulic pump switch of the hydraulic system, the PLC programmable controller is connected to the electric contact pressure gauge 2, the electric contact pressure gauge 2 is connected to the feed pump switch, and the PLC programmable controller is connected to the fault indicator light and the buzzer alarm.
2. The high backpressure safety protection and automatic alarm device for a filter press according to claim 1, wherein: The electric contact pressure gauge 1 is provided with a pressure upper limit contact and a pressure lower limit contact. The pressure lower limit contact controls the lower limit pressure of the hydraulic cylinder pressing in the hydraulic system, and the pressure upper limit contact controls the upper limit pressure of the hydraulic cylinder pressing in the hydraulic system; the electric contact pressure gauge 2 is provided with a pressure upper limit contact and a pressure lower limit contact, and the pressure lower limit contact is connected to the feed pump switch to control the back pressure of the hydraulic cylinder.