OVERLOAD BRAKE FOR TROLLEY

Abstract

An overload brake and method for trolley suspended on a flange of a load traveling apparatus girder prevents the displacement movement of a suspended load along a girder by clamping a brake between two symmetrical flange tabs of the girder. The girder is elastically deformed by the load which is applied to the girder by the contact between a surface of the girder and translation wheels that move the load along the girder. Upon sufficient elastic deformation, portions of the girder contact a brake to prevent movement of the load along the girder.

Claims

1. An overload brake for trolley, characterized by using local α angular elastic deformation of the girder loaded flange to block the trolley displacement movement along the girder by compressing a brake between two symmetrical tabs of the girder loaded flange.

2. An overload brake for trolley according to claim 1, wherein the brake is mounted between two symmetrical loaded flange tabs that form a concave C section, with the opening facing the direction of the load and symmetrical along the girder web axis.

3. An overload brake for a trolley, comprising: at least one wheel adapted to ride on a support member; and a brake member, wherein an overload condition is transmitted to the support member by the at least one wheel, causing angular deformation of the support member to press a portion of the support member into the brake member, thereby braking against translation movement along the support member.

4. The overload brake according to claim 3, wherein said support member comprises a girder with a first surface which said at least one wheel rides on, and said girder further comprises a flange tab which presses against said brake member upon a first amount of angular deformation of the girder.

5. The overload brake according to claim 3, comprising two of said wheel adapted to ride on a support member.

6. The overload brake according to claim 5, wherein said support member comprises a girder with two symmetrical flange tabs of the girder forming a concave C section, wherein said brake member is positioned in an opening of said C section.

7. A method for providing an overload brake for a trolley, comprising: providing at least one wheel adapted to ride on a support member; and providing a brake member, wherein an overload condition is transmitted to the support member by the at least one wheel, causing angular deformation of the support member to press a portion of the support member into the brake member, thereby braking against translation movement along the support member.

8. The method according to claim 7, wherein said support member comprises a girder with a first surface which said at least one wheel rides on, and said girder further comprises a flange tab which presses against said brake member upon a first amount of angular deformation of the girder.

9. The method according to claim 7, comprising providing two of said wheel adapted to ride on a support member.

10. The method according to claim 9, wherein said support member comprises a girder with two symmetrical flange tabs of the girder forming a concave C section, wherein said brake member is positioned in an opening of said C section.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is a view of a lifting and handling apparatus girder section and trolley mechanism suspended on wheels;

[0010] FIG. 2 is a drawing of the girder section with trolley showing the girder lower flange elastically deformed by the action of vertical load applied by the wheels and clamping the brake mounted on the trolley; and

[0011] FIG. 3 is a perspective drawing of the trolley and brake in absence of a girder.

DETAILED DESCRIPTION

[0012] The system according to a preferred embodiment of the present disclosure comprises the overload brake for trolley mounted on a trolley 4 that is suspended from a lifting and handling apparatus girder 1, as shown in FIG. 1. The system prevents the displacement movement of a suspended load as soon as this value exceeds the allowable value of girder 1 within its elastic deformation capacity range.

[0013] The overload brake 10 comprises a pair of wheels 3 that are mounted to ride along a surface of girder 1 to allow translation of the device and the load carried below along the length of the girder. Hoist 7 is attached to the braking device and raises and lowers, by extension and retraction of load chain 8, hook 9 carried on an end of the chain, for attaching to a load.

[0014] A brake having a pair of brake disks 2 is positioned to be mounted between the opening formed by two symmetrical loaded flange tabs 1a, 1b of the girder 1 web, the flange tabs forming a concave C section, with the opening facing the direction of the load and symmetrical along the girder 1 web axis.

[0015] As shown in FIG. 2, a view of the girder section with trolley with the hoist, load chain and hook removed for illustration, if overload lifting is attempted, the girder lower flanges 1a and 1b elastically deform by the action of vertical load applied by the circular surfaces of wheels 3 riding on the girder wheel engaged surface of the girder, which causes a local α angular elastic deformation the girder (1) loaded flange. This angular deformation moves the tabs 1a and 1b inwardly in the direction of arrows 11, causing girder flange tabs 1a and 1b to contact to brake disks 2 and to clamp the brake mounted on the trolley by the elastic deformation of the girder 1 loaded flange.

[0016] Such local α elastic angular elastic deformation is used to block the displacement movement of the trolley 4 along girder 1 by compressing the brake between the two symmetrical tabs of the girder 1 loaded flange.

[0017] In accordance with the disclosure, an improved overload brake is provided which can prevent displacement of a suspended trolley along a girder when an attempt to lift an overcapacity load is made.

[0018] While a preferred embodiment of the technology has been shown and described, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the broader aspects. The appended claims are therefore intended to cover all such changes and modifications as fall within the true spirit and scope of the technology.