Drive coupler and uncoupler

A device is disclosed for coupling and uncoupling driving and driven members. The driving and driven members each include a flange and means are provided for engaging and disengaging said flanges. When the flanges are engaged, the members are coupled whereupon torque is transmitted from the driving to the driven member. When the flanges are disengaged, the members are uncoupled and the transmission of torque is prevented.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a coupler and, more particularly, to a coupler 
for engaging and disengaging a driving shaft from a driven shaft. 
2. Description of the Prior Art 
In aircraft engines a powered drive shaft drives a generator shaft. In the 
event of a generator failure on a multi-engine aircraft, the engine 
driving the generator is shut off. However, a more desirable alternative 
is to provide means for uncoupling the failed generator from its driving 
engine so as not to affect engine operation. Various devices are known in 
the art for accomplishing this general purpose. Illustrative of these 
prior art devices are commonly assigned U.S. Pat. No. 2,989,160, issued 
June 20, 1961 to Frank Woodruff, disclosing a coupling device wherein 
brake means must be actuated to uncouple the driving and driven members 
and to prevent the transmission of torque; and commonly assigned U.S. Pat. 
No. 3,080,030, issued Mar. 5, 1963 to Henry Troeger, disclosing pneumatic 
valves for controlling pressurized air to couple and uncouple the driving 
and driven members. These devices, while adequate for specific purposes, 
do not fulfill the needs of the present invention, where a more economical 
and simpler device is required. 
SUMMARY OF THE INVENTION 
This invention contemplates a drive coupler and uncoupler for the purposes 
described and including a flange affixed to a driving member and another 
flange affixed to a driven member. The flange affixed to the driven member 
carries a pair of pivots for pivotally supporting a corresponding pair of 
plates. A rod is arranged to engage the plates and the plates are arranged 
to engage the flange of the driving member. The members are thus coupled 
and torque is transmitted from the driving member to the driven member as 
long as the plates are engaged with the flange of the driving member. 
Moments are generated so that upon displacement of the rod to disengage 
the rod from the plates, the plates pivot and are disengaged from said 
flange whereupon the driving and driven members are uncoupled. 
The main object of this invention is to provide means for coupling driving 
and driven members whereby torque is transmitted from the driving to the 
driven member, and for uncoupling said members to prevent transmission of 
torque as may be required. 
Another object of this invention is to accomplish the above with simpler 
and more economical means than has heretofore been possible. 
Another object of this invention is to uncouple a generator from its 
driving engine without shutting off the engine. 
The foregoing and other objects and advantages of the invention will appear 
more fully hereinafter from a consideration of the detailed description 
which follows, taken together with the accompanying drawings wherein one 
embodiment of the invention is illustrated by way of example. It is to be 
expressly understood, however, that the drawings are for illustration 
purposes only and are not to be construed as defining the limits of the 
invention.

DESCRIPTION OF THE INVENTION 
With reference to FIGS. 1, 2 and 3, wherein corresponding elements carry 
corresponding numerical designations, a substantially oblong flange 2 is 
integral with or permanently affixed to a driving shaft 4. Flange 2 has a 
pair of substantially circular slots 6 at opposite ends thereof as best 
shown in FIGS. 2 and 3. 
A substantially oblong flange 8 is integral with or permanently affixed to 
a hollow driven shaft 10. Flange 8 carries a pair of pivots 12 at opposite 
ends thereof. 
Each of a pair of substantially triangular plates 14 are supported at 
corresponding corners by a pivot 12. Plates 14 carry rollers 16 at corners 
opposite the corners supported by the pivots and carry stops 18 near the 
pivot corners. Rollers 16 engage corresponding slots 6 of flange 2. Plates 
14 have concavities 20 at corners opposite rollers 16. A longitudinally 
displaceable rod 22 extends through hollow shaft 10 and engages 
concavities 20 in plates 14. 
Shaft rotation is assumed to be in the clockwise direction as indicated by 
the arrow shown in FIG. 2. Torque is transmitted from driving shaft 4 to 
driven shaft 10 as long as rollers 16 of plates 14 remain engaged in slots 
6 of flange 2 as shown in FIG. 2. The arrangement is such that the 
transmission of torque causes moments to be generated about pivots 12 
tending to pivot plates 14 about the pivots in a direction which would 
disengage rollers 16 from slots 6. These moments are augmented by 
centrifugal force in the configuration shown in the Figure. The aforenoted 
pivoting is prevented by rod 22 engaging concavities 20 in plates 14 to 
effect the coupling of shafts 4 and 10 and the aforenoted torque 
transmission. 
Upon displacement of rod 22 in the direction shown by the arrow in FIG. 1, 
the rod is disengaged from the concavities and plates 14 are rendered free 
to pivot about pivots 12 in the direction shown by the arrows in FIG. 3, 
until stops 18 abut flange 8. The device is then in the configuration 
shown in FIG. 3, with rollers 16 of plates 14 disengaged from slots 6 of 
flange 2, and the driving and driven shafts being thereupon uncoupled. 
In this connection it will be understood that rod 22 may be displaced by 
solenoid means or the like, either manually actuated upon an indication 
that uncoupling of the driving and driven members is desirable or 
necessary, or automatically actuated by sensing means which senses a 
failure requiring the uncoupling as the case may be. 
Further, while a single configuration employing the principles of the 
invention has been illustrated, other configurations as well as desirable 
structural refinements are now obvious. For purposes of illustration, 
means may be provided for maintaining plates 14 in the disengaged position 
as shown in FIG. 3, and such means may include spring loading or the like 
as will be readily understood. Thus, although but a single embodiment of 
the invention has been illustrated and described in detail, it is to be 
expressly understood that the invention is not limited thereto. Various 
changes may also be made in the design and arrangement of the parts 
without departing from the spirit and scope of the invention as the same 
will now be understood by those skilled in the art.