Elevator safety brake

• US 3,942,607 A
• Filed: 09/06/1974
• Issued: 03/09/1976
• Est. Priority Date: 09/06/1974
• Status: Expired due to Term

• Current Assignee: Dane Sobat
• Original Assignee: Dane Sobat
• Inventors: Sobat, Dane
• Primary Examiner(s): Blunk, Evon C.
• Assistant Examiner(s): Rowland, James L.
• Application Number:
  US05/503,933
• Time in Patent Office: 550 Days
• Field of Search: 187/73, 187/80, 187/89, 187/90, 187/91, 187/77, 187/78, 187/68, 187/69, 188/44, 188/61, 188/63, 188/127, 188/189
• US Class Current: 187/373
• CPC Class Codes: B66B 5/22 by means of linearly-movable wedges B66B5/24 takes precedence

Abstract

The accompanying specification discloses a mine cage safety device comprising at least one friction wheel adapted to roll freely over the shaft wall or mine cage guide timber when the cage is lifted upwards and downwards in the mine shaft. When the cage accelerates past a critical level as in a free fall the friction wheel actuates a hydraulic trigger means that in turn sets off an explosive charge which instantaneously drives braking means against the timber guides to thereby arrest the free fall of the mine cage.

Claims

1. A braking device for an elevating apparatus operating within the walls of a shaft comprising in combination:

i. at least one wheel member rotatably mounted from said elevating apparatus against one of the walls of said shaft as said elevating device is moved upwardly or downwardly within said shaft;

ii. hydraulic means operated by movement of said wheel member to pump fluid at increasing pressure to a trigger device supported on a platform of said elevating apparatus;

iii. an explosion containing chamber having an explosive charge therein fixed to said elevating apparatus adapted to drive an ejection member therefrom upon release of said trigger to explode a charge contained by said chamber, said trigger actuated by increase of fluid pressure from said hydraulic means;

iv. brake members expandable from said platform against said shaft walls by said ejection means to arrest movement of said elevating device within said shaft.

2. A braking device for an elevating apparatus as claimed in claim 1 wherein said elevating apparatus operates between two guide rails fixed within said shaft and wherein said wheel member is rotatably mounted on a frame supported by said platform, against one of said guide rails as the elevating apparatus is moved upwardly or downwardly of said shaft, and wherein said brake members comprise a pair of brake shoes expandable outwardly of said platform to said one of said guide rails by said ejection member exploded from said chamber.

3. A safety device as claimed in claim 2 wherein said wheel rotatably mounted on said elevating apparatus comprises a friction wheel fixed to a frame and freely moveable along one of said guide rails as said apparatus is moved upwards or downwards along said guide rails, and having a piston arm eccentrically mounted to said wheel and connected to a hydraulic pump means to pump fluid at increasing pressure as said wheel is moved more rapidly along said guide rails by increasing acceleration of said elevating device, a valve means interconnected with said pump means adapted to release a tripping rod when pressure increases in said pumping system beyond a predetermined level and wherein said tripping rod actuates said trigger means to fire the explosive charge to actuate the ejection member.

4. A safety device as claimed in claim 2 having a first ejection member acting against a wedge to force a pair of smooth brake shoes against one of said guide rails to decelerate the elevating device and having a delay means associated with said first ejection member to trigger and fire a second explosive charge to eject a second ejection member against a wedge forcing a second pair of brake shoes against the second rail to quickly arrest the fall of said elevating apparatus in said shaft.