What Are The Causes And Solutions for The Lag of The Fume Hood Operation Window?

Cause analysis

Mechanical structure problem

Track deformation: The operation window of the fume hood is usually opened and closed by sliding along the track. If the fume hood is subjected to external force impacts for a long time or has been in use for too long, the track may deform. For instance, when moving experimental equipment, the operation window was accidentally bumped, causing local bending of the track. This hindered the sliding process of the window, resulting in a lag.

Pulley damage: The pulley is a key component for the operation window to slide on the track. The pulley may fail to rotate normally due to wear, aging or being stuck by foreign objects. For instance, if the fume hood is located in an environment with a lot of dust, the dust will enter the interior of the pulleys, increasing the resistance to their rotation. Over time, this will lead to the damage of the pulleys and subsequently cause the operation window to get stuck.

Linkage mechanism failure: Some fume hoods use linkage mechanisms to control the opening and closing of their operation Windows. If the connection parts between the connecting rods become loose, rusty or deformed, it will affect the normal movement of the connecting rod mechanism, resulting in an unsmooth sliding of the operation window. For instance, rust at the hinge of the connecting rod can cause the connecting rod to be hindered by frictional force during movement, resulting in jamming.

Electrical control problem

Motor failure: The operation Windows of some fume hoods are electrically controlled, and the motor is the power source that drives the movement of the Windows. The motor may experience faults such as winding short circuit, open circuit, and bearing damage, which can prevent the motor from operating normally and cause the operation window to freeze. For instance, if a motor operates under overload for a long time, the temperature of the motor windings will rise too high, causing a short circuit in the windings and affecting the normal operation of the motor.

Control system failure: The electrical control system of the fume hood is responsible for controlling the start, stop and running speed of the motor, etc. If the circuit board in the control system malfunctions, the sensor malfunctions or there is a program error, it may cause the motor to fail to operate according to the set instructions, and then make the operation window lag. For instance, if the sensor fails to accurately detect the position of the operation window, it will lead to a misjudgment by the control system, causing the motor to be unable to drive the window to slide normally.

Influence of external factors

Foreign object obstruction: Foreign objects may enter the tracks or pulleys around the operation window of the fume hood, such as solid particles or paper scraps that fall during experiments. These foreign objects can get stuck between the tracks or pulleys, hindering the sliding of the operation window and causing it to get stuck. For instance, during chemical experiments, some tiny crystal particles might fall onto the track, affecting the normal movement of the window.

Environmental temperature influence: In extreme temperature conditions, the mechanical components of the fume hood operation window may be affected. For instance, in a low-temperature environment, the lubricating oil inside the pulley may solidify, increasing the resistance to the pulley's rotation. In high-temperature environments, the track may deform due to thermal expansion and contraction, causing the operation window to freeze.

Processing method

Regarding mechanical structure issues

Track repair or replacement: If the track deformation is not severe, professional track correction tools can be used for repair. When making corrections, it is necessary to ensure that the straightness and levelness of the track meet the requirements. If the track is severely deformed and cannot be repaired, a new track needs to be replaced. When replacing the track, select a track of the same specification as the original one and install it according to the correct installation method.

Pulley replacement or cleaning: For damaged pulleys, new ones need to be replaced in a timely manner. When replacing the pulley, it is important to ensure that the model and specification of the pulley are consistent with the original one. If the pulley is only stuck by foreign objects, you can use small brushes, air guns and other tools to clean the foreign objects thoroughly, and add an appropriate amount of lubricating oil inside the pulley to ensure that it can rotate normally.

Maintenance of connecting rod mechanism: Check the connection parts between the connecting rods. If any looseness is found, use tools such as a wrench to tighten them. For rusty connecting rod components, rust remover can be used for rust removal treatment, and then anti-rust oil can be applied to the surface to prevent rusting again. If the connecting rod is deformed, it can be corrected with professional correction tools or replaced with a new one.

Regarding electrical control issues

Motor maintenance or replacement: If a motor malfunctions, it is necessary to first inspect the motor to determine the cause of the fault. If there is a short circuit or open circuit in the winding, a multimeter or other tools can be used for detection, and the repair can be carried out based on the detection results. If the motor bearing is damaged, a new one needs to be replaced. If the motor failure cannot be repaired, a new motor needs to be replaced. When replacing the motor, select a motor with the same parameters as the original one, such as power and speed, and connect it according to the correct wiring method.

Control system maintenance: For faults in the electrical control system, it is necessary to check whether the components on the circuit board are damaged and whether the solder joints are loose, etc. If any component is found to be damaged, a new one needs to be replaced. If the solder joint is loose, it needs to be re-welded. At the same time, the sensitivity and accuracy of the sensor should be checked. If the sensor malfunctions, a new one needs to be replaced. For program errors, professional programming equipment can be used to reprogram or debug the control system.

In response to the influence of external factors

Remove foreign objects: Regularly clean the tracks and pulleys of the fume hood operation window to prevent foreign objects from entering. You can use tools such as vacuum cleaners and brushes to clean the dust and debris around the tracks and pulleys. During the experiment, it is important to avoid dropping solid particles, paper scraps and other foreign objects onto the track.

Environmental regulation: Try to place the fume hood in an environment with a suitable temperature and avoid using it in extreme temperature conditions. If the ambient temperature cannot be controlled, corresponding measures can be taken. For instance, in a low-temperature environment, heating equipment can be used to preheat the fume hood to keep the lubricating oil in the pulley in a flowing state. In high-temperature environments, ventilation equipment can be used to cool down fume hoods to prevent the tracks from deforming due to thermal expansion and contraction.