A single-rope memorial gate type depth indicator consists of two parts. One is the device connected with the hoist shaft end at a right angle, and it transfers movement, that is, memorial gate-type depth indicator gear; and the other part is the depth indicator. The two are connected via a coupler.

Working Principle:

The rotational motion of the hoist shaft is transferred to the depth indicator via the gearing, and then transferred to the lead screw through the gear, making two vertical lead screws rotate in an opposite direction, that is, one rotates upwards and the other downwards. The number of revolutions of the lead screw is proportional to that of the spindle; therefore, it locates in the corresponding position in the shaft with the container, so is the position of the pointer of the nut on the lead screw. Through the pointer, you can point the position of the container in the shaft correctly.

The trapezoidal nut is not only equipped with a pointer but also with pawls and trailing iron. When the hoisting container is close to the unloading position of the wellhead, the pawl drives the pin on the signal pull rod, raising the signal pull rod gradually; in the mean time, the pin also moves in a horizontal direction; and the pin will break away from the pawl and fall down when reaching the reducing point. The hammer installed on the signal pull rod knocks the signal bell, sending out the deceleration start signal. A limit switch is installed on the vertical column beside the signal pull rod; the running pulley of the collision block reducer switch begins reducing speed until the machine is stopped when the hoisting container reaches a certain position. If the hoist appears overwinding, the collision iron on the trapezoidal nut will turn on the overwinding limit switch and realize safety braking.

The pin on the signal pull rod can be moved as desired. And upper and lower positions of the reducing limit switch and over-winding limit switch can be adjusted conveniently to suit different deceleration distance and overwinding distance requirements.

The speed-limit cam is driven by the turbine; provides speed limit protection through the speed-limit rheostat or selsyn, so that the hoist will not be too fast in the deceleration stage. In a lifting process, the rotation angle of each cam should be within 270-330 degrees.

Installation, commissioning requirements, use and maintenance precautions of depth indicators

Memorial gate-type depth indicator

Installation and Commissioning Requirements

The indicator scale shall be calibrated at the time of installation of the hoist, that is, to draw the grid (with a reduced proportion) corresponding to the depth of the shaft or the length of the tunnel with white paint on the scale. The pointer range is more than 2/3 of the total length of the scale.

The gearing should be flexible and reliable; and the pointer shall not touch the ruler when moving.

The installation and commissioning of the transmission shaft should ensure the gear bites well. The gap of the pair of bevel gears at the end of the shaft must be adjusted well, so as to avoid no smooth, which shall cause broken signal accidents.

Use and Maintenance Precautions

1. It should be ensured that there is enough lubricating oil in the oil tank to make the worm, cylindrical gear and bevel gear immersed in the oil.

2. Replace the oil in the tank every year

3. Always check the hinge connection and lubricate it

4. Always check the occlusion gap of the bevel gear at the end of the spindle, so as to avoid the gap is too small, which shall cause the damage of the bevel gear and lead to the broken signal accident accordingly.