1. Coarse adjustment failure
The fault phenomenon is that the lens barrel cannot be raised and lowered when the coarse focusing screw is rotated. The lifting and lowering of the microscope lens is realized by the gear driven by the rod, and the meshing wheel is fixed on the rotating shaft of the coarse adjustment knob, and the rod is fixed on the lens barrel. When the coarse adjustment knob is turned, the gear drives the bar to lift the lens barrel. If the lens barrel can not be raised and lowered, it means that the gears and teeth do not match. The common cause of failure is that the rack sleeve rotates with the coarse adjustment knob, that is, the two stop screws on the rack sleeve do not fix the rack sleeve on the dovetail guide rail. The repair method is to move the gear to the middle of the gap of the gear rod sleeve, and make the gap C of the gear rod sleeve face the sash, and then use a small screwdriver to tighten the two stop screws on the end surface of the tail rail. If it is invalid, it means that the rack is seriously worn, you need to remove the lens barrel, unscrew the fixing screws on the top and bottom of the rack, and use the rack upside down, because the wear of the rack mainly occurs on the upper part of the rack. Or cut a piece of metal sheet according to the width of the rack, make the metal sheet inlaid on the rack, fix the sheet and rack on the lens barrel with fixing screws, and plug the lens barrel for debugging. If you feel tightness, you can change the thickness of the metal sheet until it is suitable. Or buy a new rack from the manufacturer according to the original model specifications.
2. The lens barrel slides down by itself
The fault phenomenon is that when the focal length is aligned, the hand loosens the focusing screw, and the mirror will slide down by itself, resulting in inaccurate focal length. In the coarse adjustment structure of the microscope, the tightness of the gear shaft is generally controlled by the friction force between the gear rod sleeve and the coarse adjustment knob, while the friction force between the gear shaft and the gear rod sleeve is controlled by the two gears connected to the gear shaft. The coarse adjustment knob is obtained by pressing two plastic washers on the end face of the tooth rod sleeve. The tighter the grain is rotated or pressed with the end face of the gear rod sleeve, the greater the frictional force obtained. The reason why the lens barrel slides down by itself is that the washer has been used for a long time and is worn out, which reduces the friction between the gear shaft and the gear rod sleeve. caused by the torque generated. The repair method is to hold one side of the coarse adjustment knob with both hands, and tighten the coarse adjustment knob in a clockwise direction. If it doesn't work, thicken the washer. Insert needle nose pliers into the double eye nut on the end face of any coarse adjustment knob, unscrew it, remove the coarse adjustment knob, take out the plastic washer, cut a washer of the same diameter with green paper or thin plastic sheet, and sandwich it between the original washer and the coarse adjustment knob. Between the adjustment knobs, re-install it. If it is very laborious to turn the coarse adjustment knob, it means that the washer is too thick and should be replaced with a thinner washer. prevail.
3.the tilt joint is too loose
The tilt joint refers to the movable joint at the connection between the mirror arm and the mirror column. When using the microscope, the mirror arm is often tilted back to an angle that is convenient for observation. After period of use, the tilt joint may become loose, causing the mirror arm to not be tilted at will. The repair method is to insert the needle-nose pliers into the two double-eye nuts on the end face of the inclined joint respectively, and rotate clockwise until the tension of the mirror arm is moderate. If it does not work, the friction washers on both ends of the mirror arm and the mirror column may be worn. Thicken the washers, unscrew the eye nut with the beak pin, take out the rotating shaft, and cut a quill with the same diameter from green paper or thin plastic sheet. Figure Thicken the original gasket and reassemble it
it is good.
4. The pins of the reflector are too loose or too tight in the socket
There are two common types of mirror pin structures: - One is to open a slot on the pin, depending on the width of the slot to adjust the tightness of the pin in the socket - When the input pin is too loose in the socket, a flat-blade screwdriver can be used to insert it into the slot of the pin , so that the opening of the slot is enlarged, so that the tightness of the pins in the socket is suitable. Conversely, when the pins are too tight, use wire cutters to narrow the openings of the pins_upper grooves. The other is to rely on the set screw to adjust the pin to be tight in the socket. When the pin is too loose in the socket, use a screwdriver to tighten the set screw. If the pins are too tight in the socket, it is easy to twist the pins when the reflector is turned, and you can use a screwdriver to loosen the set screws.
