to view an animation of the Wagner rocking frame remontoire, it requires
Adobe Shockwave player. There are three animations, click on "GOING" to see
COLLIN - WAGNER successor company to JEAN WAGNER, PARIS, FRANCE c. 1870 -1880s.
'Rocking frame' style remontoire. Invented by Bernard-Henri Wagner (Jean
Wagner's uncle), France, c. 1850. Gravity driven, train type. 30 second cycle. Remontoire dimensions:
5"w x 3"h x 8.5"d. Below are some
photos taken of repairs made to the remontoire. Some pieces were missing and broken when
Text of voice over narrative below:
What you see is a greatly speeded up sequence of events that in real time would
take 30 seconds. All rotational directions are described using the left picture and would
be reversed in the right.
Notice first the small clockwise rotating arm behind the large wheel in the left
picture, and center rear in the right which makes one-half revolution as soon as the frame
reaches its lowest point. This arm is mounted to an arbor that meshes with the wheels
connected to main weight of the movement.
A cam and the remontoire frame are attached to an arbor that is supported and
rotates freely between the two brass cocks mounted to the center of the upper movement
support bar. Mounted on the frame is a freely rotating wheel and pinion at its front, a
small weight hanging just behind and an adjustable counterbalance at the rear. The rear
weight is set so as to allow the front weight just enough mass to drive the escapement.
The cycle begins with the end of the arm at rest upon the face of a cam. This is
the driving phase and lasts about 28 seconds. Throughout the cycle the clock train
powered by the main movement weight is locked. During this time the fall of the small,
cylindrical weight seen closest to the viewer is powering the entire escapement and
pendulum. As it pulls the frame downward, it causes the remontoire pinion to mesh with the
locked main movement wheel. This drives the wheel attached to the same arbor to turn
clockwise and the adjoining escape wheel to turn counterclockwise. Since the left wheel is
locked and the right remontoire wheel is free to move through the escapement, power is
directed from the small weight through the right wheel and to the escapement. The cam is
also rotating clockwise with the frame until the point that the end of the arm slips off
Now begins the recoil phase and lasts about 2 seconds. At this point the
main movement train unlocks and the left wheel, powered by the main weight of the clock
movement, begins to turn counterclockwise, meshing with the remontoire pinion.
happens at a faster rate than the wheel it is attached to is turning the escape
wheel. This difference causes the pinion to ride along in the direction of the left
wheel. Pulled by the remontoire pinion the cam and frame assembly rotate counterclockwise
raising the weight upward while the arm makes one half revolution. To avoid jarring the
remontoire, the speed at which the frame recoils is mediated by a small adjustable fly
seen in the right picture. During this time the main movement is also advancing the clock
in one increment equal to 30 seconds. This is demonstrated by the slight clockwise
movement of the two pronged fork located on the takeoff wheel. The recoil continues until
the cam face has moved back into its starting position, blocking the arm and locking the
main movement wheel train again. All the while power is uninterrupted to the remontoire
wheel driving the escapement and keeping a constant power supply throughout the cycle.
The sequence should be seen as the small weight giving a constant source of
power to the escapement at all times. The small weights potential energy is
recharged periodically from the larger clock movements main weight before it
exhausts its energy by reaching the end of its limited travel. The right wheel to the
escapement is always being driven, the left movement wheel is always a driver, while the
pinion always drives and is periodically driven.
This is the principal of a differential gear system. The differential is the
general mechanical concept employed in all gravity driven train remontoire.*
The action you see, especially in the rotation of the escape wheel is
necessarily distorted. The time the remontoire is driving is far greater than its recoil
phase. So to make the animation fit into a reasonably sized file the driving phase was
greatly speeded up while the recoil phase was slowed down a bit.
* The Robin type is excepted. While it is gravity driven, it uses a flexible
line or chain to achieve what is done via differential gearing.