Warning and safety system indicating truck trailer tip-over condition

• US 4,988,974 A
• Filed: 07/17/1989
• Issued: 01/29/1991
• Est. Priority Date: 07/17/1989
• Status: Expired due to Fees

• Current Assignee: Gerald D. Bailey, Tommy J. Fury
• Original Assignee: Gerald D. Bailey, Tommy J. Fury
• Inventors: Bailey, Gerald D., Fury, Tommy J.
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US07/380,498
• Time in Patent Office: 561 Days
• Field of Search: 340/431, 340/440, 340/689, 340/686, 340/665, 340/666, 340/671, 340/672, 340/673, 340/674, 340/685, 280/433, 280/432
• US Class Current: 340/431
• CPC Class Codes: B60P 1/045 Levelling or stabilising systems for tippers suspensions with levelling or stabilising means for vehicles in general B60G17/00, B60G21/00, using ground-engaging vehicle fittings B60S9/00

Abstract

A warning and safety system for tractor-trailer dump trucks to indicate that the raised trailer is in a precarious position and in danger of tipping over, which system measures the pivot angle or the angle of revolution of the front end of the trailer. When the raised trailer is in an unstable position and begins to tip over, the front end of the trailer pivots on the hydraulic telescoping cylinder extending from the fifth wheel of the trailer. Mounted directly onto to hydraulic telescoping cylinder is an instrument sensitive to angular motion, or, alternatively, mounted on the fifth wheel of the tractor is a pivoting canister containing that instrument, from which a cable extends, parallel to the hydraulic telescoping cylinder, to the bottom of the front end of the trailer, where the cable engages with a pulley arrangement securely mounted on the cylinder well of the trailer. When the warning and safety system detects that the tipping angle of the trailer is equal to or greater than predetermined, but adjustable, critical angles, various first stage and second stage alarms are triggered. The first stage alarms may comprise audio and visual alarms, whereas the second stage alarms automatically dump the oil from the hydraulic telescoping cylinder back into the oil reserve tank and immediately lower the trailer. The location of the pivoting canister on the fifth wheel prevents spurious false alarms, as does the time-delayed dampened instrumentation within the canister. Power is supplied automatically to the warning and safety system either by using a pressure-sensitive switch which turns on the system as soon as the trailer is raised a small distance, or by wiring a switch into the gate-release switch.

Claims

1. In a tractor-trailed truck, including a trailer capable of being raised by a hydraulic cylinder mounted between the front end of said trailer and the fifth wheel of said trailer, means for detecting the side-to-side or tip rotation of the front end of said trailer about the connection between said hydraulic cylinder and said fifth wheel, said detecting means including tip angle measuring means mounted adjacent to said fifth wheel, and means connecting said tip angle measuring means with one of said front end of said trailer or said hydraulic cylinder adjacent said front end of said trailer, said connecting means moving though substantially the same angle as said front end of said trailer, when said front end of said trailer undergoes tip rotation, to thereby proportionally rotate said tip angle measuring means.

2. The combination as set forth in claim 1, wherein said tip angle measuring means includes means for rotatably mounting said tip angle measuring means.

3. The combination as set forth in claim 2, wherein said mounting means is attached to one of said fifth wheel or said hydraulic cylinder in a location adjacent to said fifth wheel.

4. The combination as set forth in claim 1, wherein said connecting means includes a cable connected to said tip angle measuring means.

5. The combination as set forth in claim 4, wherein said connecting means includes means for maintaining said cable in tension as said trailer is raised or lowered by said hydraulic cylinder.

6. The combination as set forth in claim 5, wherein said tip angle measuring means includes means for rotatable mounting said tip angle measuring means.

7. The combination as set forth in claim 6, wherein said mounting means is attached to one of said fifth wheel or said hydraulic cylinder in a location adjacent to said fifth wheel.

8. The combination as set forth in claim 7, wherein said tip angle measuring means includes an inclinometer.

9. The combination as set forth in claim 1, wherein said tip angle measuring means includes means for adjusting and setting at least one angle indicative of an unstable position in which said trailer is in danger of tipping over, means for comparing said tip angle of rotation to said one set angle, and means for signaling when said tip angle of rotation is equal to or exceeds said one set angle.

10. The combination as set forth in claim 9, further including means for adjusting and setting a second angle, said second angle being greater than said one set angle, means for comparing said tip angle with said second angle and means for releasing hydraulic fluid from said hydraulic cylinder when said tip angle of revolution is equal to or exceeds said second angle, thereby automatically lowering said trailer.

11. In a tractor-trailer dump truck having a trailer with an extendible cylinder connected between a fifth wheel on said trailer and the front end of said trailer for lifting said front end of said trailer, a method of preventing damage to said trailer when said trailer is raised to dump materials and said tractor-trailer dump truck is an unstable condition and said trailer may tip over, said method comprising the steps of:

(a) measuring the pivot angle about which the front end of the extended trailer pivots about said fifth wheel along a radial path determined by the movement of the connection between said front end of said trailer and said cylinder about said fifth wheel;

(b) comparing said pivot angle with a predetermined critical angle representing a deviation of said front end of said trailer from the vertical at which said trailer is in an unstable condition; and

(c) signaling an alarm when said pivot angle equals or exceeds said critical angle.

12. The method as set forth in claim 11 further including:

(a) comparing said pivot with a second predetermined critical angle, said second critical angle being greater than said predetermined critical angle; and

(b) signaling a second stage alarm which automatically lowers said trailer along said cylinder when said pivot angle equals or exceeds said second critical angle.

13. In a trailer dump truck having a tractor and a trailer with a fifth plate, said trailer capable of being raised by a hydraulic telescoping cylinder, said hydraulic cylinder being coupled to said fifth plate and coupled to the front end of said trailer, comprising in combination:

(a) means for detecting an angle of revolution of said trailer around said fifth plate along a radial path determined by the movement of said trailer-hydraulic coupling about said fifth plate;

(b) means for adjusting and setting at least one critical angle wherein as said angle of revolution approaches said one critical angle said trailer approaches an unstable position in danger of tipping over;

(c) means for comparing said angle of revolution to said one critical angle;

(d) means for signaling when said angle of revolution is equal to or exceeds said one critical angle;

(e) means for mounting said detecting means said adjusting and setting means, and said comparing means;

(f) a cable means connected to said detecting means and a cable-rewind mechanism mounted on the underside of said trailer to maintain said cable taut; and

where in when said trailer is raised and approached an unstable condition, said cable causes said detection means to pivot through said angle of revolution thereby activating said signaling means when said angle of revolution is equal to or exceeds said one critical angle.