OT-2026-000003240
Crane level indicator device
- Published
- Permanent URL
- https://opentechnical.org/p/OT-2026-000003240
- Classification
- Lifting, Positioning & Manipulation › Hoists and Cranes
- Original source
- US-5673491-A, the United States Patent and Trademark Office, 7 October 1997
- Document SHA-256
- 7dfedade939c91fa1caf40e0d3bc37c91b1a292db296f77447281023a4d14c4a
Disclosed is a level indicator device for cranes. A sensor sending unit fixed to the crane base utilizes a free swinging pendulum with a tip which activates sensor portions on a sensor board. An out-of-level attitude of the crane tilts the sensor sending unit and thus moves the pendulum tip to contact a specific sensor portion defined by the crane attitude. The sensors are connected to circuitry including a programmable array logic chip which generates a signal representative of a binary number corresponding to the position of the particular sensor activated. A serial to parallel converter converts the parallel binary number to a serial number and transmits radio frequency signals with said serial binary number indicative of the pendulum position. The RF signal is received by a receiver indicator unit located in the operator control station of the crane. Circuitry converts the signals to indicator activating signals for an indicator panel on the receiver indicator unit. The indicator panel displays the direction and degree of tilt of the crane base by appropriately positioned visual indicators laid out in quadrants to incrementally indicate the degree and direction of the crane tilt whereby the crane operator may operate the crane leveling controls.
Abstract
Disclosed is a level indicator device for cranes. A sensor sending unit fixed to the crane base utilizes a free swinging pendulum with a tip which activates sensor portions on a sensor board. An out-of-level attitude of the crane tilts the sensor sending unit and thus moves the pendulum tip to contact a specific sensor portion defined by the crane attitude. The sensors are connected to circuitry including a programmable array logic chip which generates a signal representative of a binary number corresponding to the position of the particular sensor activated. A serial to parallel converter converts the parallel binary number to a serial number and transmits radio frequency signals with said serial binary number indicative of the pendulum position. The RF signal is received by a receiver indicator unit located in the operator control station of the crane. Circuitry converts the signals to indicator activating signals for an indicator panel on the receiver indicator unit. The indicator panel displays the direction and degree of tilt of the crane base by appropriately positioned visual indicators laid out in quadrants to incrementally indicate the degree and direction of the crane tilt whereby the crane operator may operate the crane leveling controls.
1. Drawings
[0001]Sheet 1.
[0002]Sheet 2.
[0003]Sheet 3.
[0004]Sheet 4.
[0005]Sheet 5.
Publication information
Citation
OpenTechnical Publication OT-2026-000003240, “Crane level indicator device,” published September 15, 2026 at 19:55:01 UTC, https://opentechnical.org/p/OT-2026-000003240.
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Terms
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