Anti-sway apparatus for trailers

• US 4,082,309 A
• Filed: 02/04/1977
• Issued: 04/04/1978
• Est. Priority Date: 02/04/1977
• Status: Expired due to Term

• Current Assignee: James E. Fox
• Original Assignee: James E. Fox
• Inventors: Fox, James E.
• Primary Examiner(s): Peters, Jr., Joseph F.
• Assistant Examiner(s): Schrecengost, R.
• Application Number:
  US05/765,786
• Time in Patent Office: 424 Days
• Field of Search: 280/432, 280/446 R, 280/446 B, 200/83 S, 188/106 P, 188/158, 188/163, 188/77
• US Class Current: 280/455.1
• CPC Class Codes: B60D 1/32 involving damping devices

Abstract

A sway control apparatus for a trailer comprising an electromagnetically actuated brake drum mounted horizontally on the draw bar frame of the trailer. Means are provided on the rotatable drum of the brake to which are connected ends of chain links. The other ends of the chains extend forward and connect to opposite ends of a cross bar member fixed to the hitch means directly below the hitch ball. The cross bar member and the two spaced chains connected to the brake drum form a parallelogram which is normally free to shift positions during normal driving. When swaying occurs, the sway control brake is manually actuated to fix the parallelogram in position thereby preventing or dampening the return sway. A pressure sensing device is fitted at the side of the trailer adjacent the rear thereof. The pressure sensing device will actuate a switch when air pressure is exerted on the side of the trailer sufficient to cause swaying of the trailer. This pressure switch closes a separately energized circuit to the sway control brake when the sway of the trailer is initiated by air pressure caused by passing truck vehicles. This circuit operates independently of the drivers manual control to immediately prevent initiation of the trailer sway caused by the side air pressure.

Claims

1. An anti-sway apparatus for a towing and trailer vehicle combination comprising the combination of:

means on said trailer vehicle connecting said towing vehicle for braking the sway of said trailer vehicle;

means in a side of said trailer vehicle for sensing change in air pressure against said side of said trailer vehicle;

electric circuit means energized by said means in said side of said trailer vehicle, said energized electric circuit means actuating said means on said trailer vehicle to brake the sway of said trailer vehicle.

2. An anti-sway apparatus for a towing and trailer vehicle combination comprising the combination of:

means on said trailer vehicle connecting said towing vehicle for braking the sway of said trailer vehicle, said means comprising a freely rotatable brake drum member, brake shoe members for bearing against said drum member and an electromagnetic device to move said shoe members against said drum member;

means in a side of said trailer vehicle for sensing change in air pressure against said side of said trailer vehicle;

electric circuit means energized by said means in said side of said trailer vehicle, said electric circuit means energizing said electromagnetic device to brake said drum member.

3. In a towing and trailer vehicle combination wherein said towing vehicle is provided with brake actuating means, an electric circuit energized by said brake actuating means and hitch bar means extending rearwardly from said towing vehicle, and wherein said trailer vehicle is provided with draw bar means, and hitch means for connection to said hitch bar of said towing vehicle, an anti-sway apparatus for said trailer vehicle comprising the combination of:

a drum brake housing comprising a freely rotatable brake member horizontally mounted to the draw bar of the trailer vehicle;

actuating means to brake said freely rotatable brake member;

a laterally extending bar member connected to said hitch bar means;

spaced connecting members provided on said freely rotatable brake member;

elongated link members connecting said connecting members on said rotatable brake member and the ends of said laterally extending bar member forming a variable parallelogram configuration; and

power transmission means connecting said brake actuating means of said towing vehicle and said actuating means for braking said rotatable brake member of said trailer vehicle; and

a pressure sensing means provided on the side of said trailer vehicle, an electric circuit independent of said brake actuating means of said towing vehicle, including said actuating means to brake said freely rotatable brake member, a switch actuated by said pressure sensing means and an electric power source.

4. An anti-sway apparatus for a towing and trailer vehicle combination comprising the combination of:

pressure sensing means on the side of said trailer vehicle;

a drum brake housing comprising a freely rotatable brake member horizontally mounted to the draw bar of the trailer vehicle;

actuating means to brake said freely rotatable brake member; and

stabilizing means connecting said rotatable brake member to said towing vehicle; and

an electric circuit including said actuating means to brake said freely rotatable brake member, a switch actuated by said pressure sensing means and an electric power source.

5. The anti-sway combination of claim 4 wherein said means to brake said freely rotatable brake member is further characterized as being an electromagnetic device linked to brake shoes adapted to bear against said freely rotatable brake member.