ORBITA Sempre for the Hand-Wound Watch
“SEMPRE” is the first and only watch winder for virtually any hand-wound mechanical watch. The Sempre watch winder is totally unique in concept, as it replicates the human action of fingers winding a watch crown.
The SEMPRE substitutes a mechanical finger arrangement, called a “collet”, which grasps the watch’s crown securely and rotates it. Several different size collets are provided to fit any watch crown diameter from 3 to 9 millimeters. The collet is fixed to the cylinder power shaft at the heart of which there is a ball bearing set in motion by the electric motor through the system of cog-wheels. The collet will open if you press the piston on the other side of the power shaft. The piston sets the collet on the winding crown.
Just as an individual winding senses the increasing turning resistance of the crown as the watch is being wound, the microprocessor “brain” of the SEMPRE monitors the electrical current drawn by the gear motor as it rotates. The amount of force required to wind the mainspring of a mechanical watch, known as the winding torque, increases as the watch is being wound. As the torque increases, the drive motor draws more current. The control circuit is user-adjustable to shutdown the system when it senses that the current has reached a pre-set limit, one which is well below the maximum torque that the mainspring can handle. To prevent “overbanking” the drive reverses the crown momentarily after shutdown.
For safety purposes, the drive system is fitted with a mechanical slip-clutch, which has been factory set to slip at a safe torque in the event of a microprocessor failure. This redundancy eliminates any possibility of stressing or breaking the mainspring of an expensive and, perhaps delicate, mechanical watch.
Automatically turns on every twenty-four hours. Upon actuation, the drive motor begins rotating the collet for 8 minutes. With the collet rotating at approximately 6 rpm, this provides a maximum of 48 crown rotations per day. However in practice, the actual number of rotations is controlled by the current feedback circuit whose priority is to shut down the motor based on torque, rather than by time.
Interestingly, the SEMPRE will also wind “self-winding” automatic watches.
The winding action of an automatic differs from a hand-wound mechanical in that there is a built-in slip-clutch in the mainspring mechanism to prevent over winding rather than a finite stop as in a hand-wound. In this case, the timing circuit of the SEMPRE comes into play as there may not be enough current draw increase to signal the system to shut-down automatically. Either way, this hybrid control circuit provides redundant safety for winding any type of mechanical; hand wound or automatic.
New Orbita Tourbillon 1 Watch Winder
In use, after the proper collet has been selected, the watch is placed in position on a mounting “shuttle” which supports both horizontally and vertically. All contact points are non-metallic, protecting the finely finished surfaces from scratching or abrasion. Using a provided “spacer” even allows watches with screw-down crowns to be wound safely and conveniently. Many hand wound pocket watches can be accommodated with this system by using the supplied extender kit.
Operating by battery, the winder can be stored in a safe for 10 to 12 months without attention. Alternately, the winder may be powered with the high quality “switcher” type AC/DC converter supplied with each unit, which operates at any voltage from 90 to 240 VAC, 50 or 60 hertz and provides perfect 6 VDC.
The winder is housed in an elegant maple burl veneer case with a plate glass viewing pane and solid brass, gold-plated lock. All hardware is solid brass, with all exposed parts gold-plated and lacquered for durability. There is also a model made of calfskin.
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