DAVID HENRY VROOM
Pilots at Comanche Way, Tucson, AZ

License number
Arizona A1977675
Issued Date
Jan 2016
Expiration Date
Jan 2018
Category
Airmen
Type
Authorized Aircraft Instructor
Address
Address
1501 W Comanche Way W COMANCHE WAY, Tucson, AZ 85755

Professional information

David Vroom Photo 1

Reversible Ratchet Mechanism

US Patent:
7341267, Mar 11, 2008
Filed:
Jun 23, 2005
Appl. No.:
11/159575
Inventors:
David H. Vroom - Tucson AZ, US
International Classification:
B62M 1/14
US Classification:
280250, 280251, 74 25, 74163
Abstract:
A reversible ratchet mechanism includes a pair of roller clutches set to operate in opposite directions when engaged by a belt. During the forward motion of the ratchet assembly in either direction of propulsion of the belt, one roller clutch is disengaged while the other is engaged and locked, thereby propelling the belt. During the backward stroke, the engaged roller clutch is free to rotate. The result is that the reciprocating motion of the assembly is converted into the linear motion of the belt. The ratchet assembly includes a shift mechanism to reverse the engagement of the roller clutches and change the direction of propulsion of the belt produced by the push/pull action of the operator. The invention is advantageously used in conjunction with a wheelchair.


David Vroom Photo 2

Hydroset Pressure Relief System

US Patent:
4147309, Apr 3, 1979
Filed:
Jun 29, 1977
Appl. No.:
5/811208
Inventors:
David Vroom - Tucson AZ
Assignee:
Duval Corporation - Houston TX
International Classification:
B02C 204
US Classification:
241215
Abstract:
A pressure relief system for a gyratory crusher is disclosed in which two separate but interacting fluid assemblies function, respectively, to adjust the operating position of the crusher cone of the gyratory crusher and to control the pressure above which the pressure relief system is activated. The system operates to relieve excessive pressure caused by the introduction of uncrushable foreign matter into the crushing chamber and to facilitate the elimination of such matter from the crusher.