Gear check device

Thread Content

Gear stop devices: This time I found some information on gear stop devices, which are mainly used in watches to prevent the gears from rotating in reverse after the spring is wound. There are various designs and principles behind these devices, as well as special gear sets such as differential gears and compound gears (I guess that covers them all). Those who are interested can take a look.

Gear stop devices

Function of the stop device
The stop device consists of what is commonly referred to as a stop element (indicated by the red circle on the left in the image) and a positioning spring (indicated by the red circle on the right). The stop element is usually located next to the gear of the large steel wheel, and thanks to the elastic force of the positioning spring, it continuously makes contact with the gear of the large steel wheel, producing a slight sound. The nature of this sound varies depending on the design of the stop device. The function of this stop device is to ensure that the axis of the spring box rotates in only one direction, thereby preventing the spring from unwinding in the reverse direction. In short, the combination of the stop element and the positioning spring serves to make the winding process more stable and reliable. 　　 　　Image: The small steel wheel hub shaft (indicated by the red circle) has a special Y-shaped design; the positioning spring (A) is shaped as a large curve and is located on the side of the large steel wheel. 　　 　　Image: On the 3/4 plate, the large and small steel wheels are visible; the positioning reed (A) is fixed on the side of the small steel wheel, so the distance between the stop member (indicated by the red circle) and the reed is short. 　　I. Design of retro-style check valves The biggest difference between the approach used for check valves in the 1950s and 1960s and the current standard practices is that the position of the positioning reed was exposed outside the large steel wheel. 　　 　　Images: Every check device must have a positioning spring; the function of this spring is to withstand the force exerted by the returning stop element. It is sometimes hidden beneath the large steel wheel, but by paying close attention to the gap between the gear and the stop element (as indicated by the red circle), it is possible to see traces of this positioning spring, which appears as wires of varying thicknesses. 　　 　　Image and text: A crescent-shaped design can be seen in the center of the left image. (On the right of the image), it is clear to see the baffle (indicated by the red circle) as well as the design of the wire-shaped positioning reed (A); its wire is not hidden inside the large steel wheel. II. Design of standard check valves The so-called standard design takes into account cost considerations as well as efficiency in production; therefore, the standard design features diaphragms made of steel wires of varying thicknesses. In some cases, these wires are concealed beneath large steel wheels, while in other cases they remain visible. Using steel wires is cost-effective, but the downside is that they are prone to breaking once they rust. 　　 　　Image and text: Design of a strip-shaped check device, which features a strip of steel with a hollow area in the middle; a large steel wheel is placed inside this strip, and there is a sharp-angle design within the strip that allows it to catch the serrated gears. Additionally, the check mechanism shown in the upper right diagram operates on a principle similar to that of the P.P mentioned above; the only difference is that the steel bar of the check device passes beneath the large steel wheel, resulting in very high stability. 　　 　　Images: What sets its check mechanism apart from other designs is that it combines the positioning reed with the stop elements into a single steel spring (as indicated by the red circle). Images: It features two large steel wheels (A and B); these wheels allow for the use of two spring boxes and enable winding in both directions. When wheel A rotates in engagement with the smaller wheel C, the check mechanism prevents wheel B from moving, and vice versa. Winding is possible in both directions. There are gears surrounding the cover shaft, and between the large wheels and the cover shaft there are two stop elements along with positioning reeds. 　　Source: twforum.wwwmonline.com/viewtopic.php?=&p=14133 Differential bevel gears: These three-dimensional differential gears connect the teeth of the spring box to the ratchet gears; they operate on the same principle as differential gears. The intermediate gear rotates around the axis center, and when the resistance on both sides is equal, the rotation speeds of the two gears are the same as that of the axis center. If the resistances differ, the gear with greater resistance will rotate more slowly, while the one with less resistance will rotate faster. “Cardan joint”: The winding hole on the back of the watch and the five plates inside the movement are all perpendicular to each other. When energy is transmitted to the balance wheel through the gear train via a “chock” at the back of the watch, the cardan joint plays an important role in this situation, as it allows tools to be inserted from various directions in order to transfer energy. Furthermore, we can see a three-dimensional miniature bevel gear on the back of the watch; through this gear, the sources and destinations of kinetic energy in both vertical and horizontal directions are organized in terms of direction.