ITBA20090005A1 - DEVICE FOR TRANSFORMING CAMPS THE ROTARY MOVEMENT OF THE HANDS OF A CLOCK IN AN ALTERNATE RETROGRADE MOVEMENT ALONG A BOW OF 180 DEGREES - Google Patents

Description

DESCRIPTION OF THE INDUSTRIAL INVENTION ENTITLED: "CAM DEVICE TRANSFORMING THE ROTARY MOVEMENT OF THE HANDS OF A CLOCK INTO A RETROGRADING ALTERNATE MOVEMENT ALONG AN ARC OF

180 GRADT ',

- BACKGROUND OF THE TECHNIQUE: the device described below allows the movement of the hands of a rotary clock to be transformed into retrograding alternating, along an arc of 180 (one hundred and eighty) degrees, instead of the 120 (one hundred and twenty) degrees of extension reached so far . - OBJECTIVE THAT INNOVATION INTENDS TO ACHIEVE: to improve the existing technology by bringing it to the state of the art, with the achievement of the maximum extension and the best possible reading of the time, ensuring maximum precision, reliability and ease of operation.

- ANALYSIS OF THE ACHIEVED RESULT: Below are the parts making up the entire device, and in particular the functions and technical characteristics of the cam, the hand and the bridge, object of this patent (Table 1):

The aforementioned device has the dial (1) of the clock as its main reference plane: on this plane, at a predetermined point (2), a hole of sufficient diameter is made to allow entry (from the rear) and free rotation of the axis (2) of a common wall clock movement, on which the special motion transformer cam (3-4-5-6) is then pivoted, able to fully manage (Table 2):

1. the rotation of a hand (9) along an arc of 180 degrees, starting from point (12a) and arriving at point (12b), carried out in:

• twelve hours, if applied to the hour axis;

• sixty minutes, if applied to the minute axis;

• sixty seconds, if applied to the seconds axis.

2. its sudden return ("retrogradation") back, up to the starting plinth (12a), rapidly traveling backwards along the same path taken for the advancement;

3. the infinite repetition of points 1) and 2).

The cam (3-4-5 -6) is made up of three plates (Table 1):!

• the first (5) and the second (6), placed on the same plane, shaped in such a way as to have a particular curved composite profile (profiles 5a, internal, and 6a, external), necessary to precisely guide the movement of the hand (9) along an arc of 180 degrees, and allow its sudden return and stop to the starting point (12a), to restart the cycle. These plates, thus drawn, become real special cams, and subsequently, in the description that follows, they will always be called "cams". In particular, the first cam (5) governs - through its "internal" profile (5a) - the movement of the hand (9) for the first six hours - from 12.00 (point 12a) to 06.00 - passing "materially" the control of the hand (9) to the second cam (6), governing the other six hours - through its “external” profile (6a) - from 06.00 to 12.00 (point 12b);

the third plate (3), placed on a parallel plane and below the plane of the first two (5) and (6) at a suitable distance, by means of the columns (4), pivoted on the three plates (3), (5) and (6), acts as a "loom", and has the dual task of:

1. keep the two cams (5) and (6) at a certain distance and reciprocal inclination and 2. allow them to rotate around the clock rotation axis (2) in order to ensure the correct management of the movement of the hand (9 ), indicator of time.

The pointer (9) is pivoted on a pin (10) - acting as an axis of rotation - whose distance from the axis of rotation of the cam is less than the radius of action of the cam itself: it follows that, if the aforementioned pin the cam itself (and more precisely the profile

f inside 5a of the cam 5), in its rotation, would “hook” the aforesaid pin (10), stopping its motion.

To overcome this drawback, the pin (10) of the pointer is pivoted in the center of a special bridge (11), welded to the underlying surface (1) and placed at a height higher than both the rotation of the pointer and the rotation. of the cam: the adoption of the bridge (11) allows the pin (10) to be suspended at a height higher than that of the rotation plane of the pointer (9), so as not to continue below this plane and to allow free rotation of the underlying cam.

The aforementioned pointer (9) has, near its rear overhang, a pin (8), equipped with a special "groove", which acts as a "guide": the profiles (5a) and (6a) of the cam thus slide aH inside the throat, always ensuring contact with the lancet. The pin (8) is welded to the hand and its axis is normal both to the plane of the hand itself and to the plane (1) of the clock face.

OPERATION (Table 1):

1. Given a fan-shaped dial (1) with an amplitude of 180 °, subdivided into 12 circular sectors of 15 ° each indicating time spaces of one hour (or five minutes, or five seconds, depending on which hand examines: hours, minutes or seconds, moved by the respective cams) and delimited by 13 notches (from number 12a to number 12b, counterclockwise), the first and last of which both correspond to that which - in a normal dial 360 ° - the 12.00 hour mark is considered, the hand ^ (9) starts its motion, starting from the mark 12a;

2. In this position, the hand (9) (for simplicity, we will take for example the operation of the hour hand only) is perfectly horizontal and superimposed on the "starting" notch (12a): to keep it in this position, cam number (5), which - suitably oriented with respect to its rotation axis (2) - “hooks”, like a fingernail, the pin (8) - located in the rear part of the lancet;

3. The internal curvilinear profiles (5a) and (6a) are designed in such a way as to allow - through their sliding in the groove of the pin (8) - the angular displacement of the pointer (9) by 1 ° counterclockwise, at each 2 ° clockwise angular displacement of the “cam” itself;

4. It follows that each clockwise angular displacement of the "cam" equal to 30 ° coincides with a counterclockwise angular displacement of 15 ° of the pointer (9), and that therefore to each complete clockwise rotation of 360 ° of the "cam" corresponds u has 180 ° counterclockwise rotation of the hand;

5. The hand (9) is guided by the cam (5) in its path from 12 (12a) to 6 o'clock, through the “internal” profile (5a), ie the one facing its rotation axis (2); 6. Once reached 6 o'clock, the pin (8) ends its sliding along the internal profile (5a) and passes, through a special calibrated groove (7), on; external profile (6a) of the cam (6), to make the second part of the path that will take the hand (9) from 6 to 12 (point 12b). The groove (7) has a size just sufficient to allow the passage of the pin from the profile (5a) to the profile (6a);

7. The pin (8) will thus slide along the entire "external" profile (6a) (ie facing in the opposite direction to that of its axis of rotation) of the cam (6), gradually bringing the hand from 6 to 12 ( point 12b): the pin (8), having finished sliding on the profile (6a), will lose contact with the cam (6) and therefore also its function as a guide for the pointer, which, suitably equipped with a suitable and common device return (9a), attached to the same (spiral spring, welded at one end to the pointer (9) and at the other end to the bridge (11)), it will not go into disarray, but will return; abruptly back, retracing in the opposite direction ("retrograding" clockwise, therefore, from point 12b to point 12a), in an instant, the angular path 12a - 12b, previously carried out in the times already mentioned above.

8. Retrograding (table 2, figures (1) and (5)) is possible, therefore, thanks to the particular design of the cam - frame complex, which leaves ample space - for the back of the pointer - to retrograde freely and instantly from the terminal portion of the outer profile (6a) of the cam (6) until it stops on the initial portion of the inner profile (5a) of the cam (5), which will revert to the rotation cycle of the pointer (9).

Claims (9)

CLAIMS 1. “Device (Table I) with cams transforming the movement of the hands of a rotary clock into alternating retrograde along an arc of 180 degrees”, comprising (in the most complete version, consisting of three cams); • a common wall clock mechanism, equipped with its three spheres (hours, minutes, seconds), placed on a plane below that of the dial (1); • three pairs of cams, each of which held together by a special frame, keyed on the three spheres of the watch (instead of the three classic hands), having the function of governing the retrograde alternating motion of the hour, minute and second hands placed on a secondary axis, through the sliding of the cam profiles on special pins equipped with grooves, placed orthogonally, on the ends of the hands opposite to those measuring the time; • three bridges, having the function of suspending the three hands each on a plane higher than that of rotation of the respective cams, the latter having a radius of rotation greater than the distance between the axis of the clock mechanism (on which the three cams) and the axis of rotation of the hands (suspended from the aforementioned bridges); 2. Device as per claim 1 (table 1), characterized by the fact that the profiles (5a) and (5b) of each pair of cams governing the movement of the corresponding hand (through the sliding on the profiles of its pin with groove ) are, in order, the internal one of the first and the external one of the second cam, and have a design such as to make the governed hand complete the regular path of 180 degrees at a constant angular velocity (the angular velocity of the hand is equal to half of the angular one reached by the cam), and its sudden return ("retrogradation") to the starting point. 3. Device according to the preceding claims (table 3), characterized in that the rotation radius of the cam (3-4-S-6) is greater than the distance between the rotation axes of the cam and the pointer, and that , to allow the rotation of the latter, the axis of the same is placed and suspended on a special bridge (11) lying on an axis placed at a height higher than that of the respective cam, so as to allow this last is free rotation below the axis of rotation of the hand. 4. Device as per the preceding claims (table 1), characterized by the fact that each single hand is equipped with a spiral spring (9a) (or, alternatively, with a special tie rod, connected to a suitable counterweight), for the sudden recall of the same to the starting point, once it has finished its run on the profiles of the cams, a hand composed of two ends, the first, having the task of indicating the time on the dial; the second, equipped at its end with a special pin, having the task of keeping the pointer always in contact with the profile of the cam. 5. Device as per the preceding claims (table 2), characterized by the fact that the pair of cams governs the movement of the hand in the following way: the first cam, with its internal profile, allowing the sliding of the pin equipped with the groove of the hand for the first 90 degrees, and the second cam, with its external profile, for the next 90 degrees. The aforesaid pin of the pointer passes from the internal profile of the first cam to the external profile of the second by passing through a slot between the two cams having just enough width to allow passage without friction or play of the pin itself. 6. Procedure for drawing (table 3a) the internal and external profiles of the cams, characterized by the use of a disk divided into twelve 30 ° circular sectors, and a 180 ° circular sector, divided into two equal parts by a vertical axis passing through the centers of rotation of the sector and of the disc (placed at a suitable distance between them), the circular sector being divided into twelve minisectors with a width of 15 ° each, the center of rotation of the circular sector being positioned inside of the area of the aforesaid disc, on the aforesaid diametrical axis, at a convenient distance from the center of rotation of the disc. such as to allow a hand, rotating on the pivot of the circular sector, to mark Torah on the latter. 7. Process according to claim 6 (table 3), characterized by the fact that the first point of the cam profile is obtained by positioning: 1) the disc so that its diametrical axis matches the axis dividing the sector of 180 ° (direction 2 - 10, table 1) and 2) the hand so that its end marking the time is positioned exactly on the first axis of the circular sector (direction 10 - 12 °, table I) and the opposite end , on the other hand, equipped with a nib, keyed orthogonally to the axis of the hand, placed at a convenient distance from its axis of rotation, and placed orthogonally to the plane of the dial, mark the first point on the disk, on axis 12b - 10 (pl. 1). 8. Process according to claim 7 (table 3), characterized by the fact that the subsequent points of the profile are obtained by rotating from time to time 1) the disc, clockwise, by 1 ° (one degree) and 2) the hand placed on the sector, 30 '(half a degree) counterclockwise, marking on the disc all the points on which the nib rests (placed, for the construction of the profile, in place of the pin 8), the definitive profile obtained from the union of the same. 9. Application of the process of claims 6, 7, and 8 (table 3b), to draw a particular cam profile causing the rotation of the hour hand on a sector of 180 ° in a time span of 24 hours , characterized by the use of 1) a disc divided into twenty-four sectors of 15 ° each and 2) a circular sector of 180 ° divided in turn into twenty-four sectors of 7 ° 30 '(seven and a half degrees), the final profile thus obtained by creating a special cam with a partially "helical" and partially flat profile, in which individual profiles (internal and external) are no longer placed on the same axis but create a "screwing" effect, as their design must allow : 1) a single excursion of the hand on the sector of 180 ° in a span of twenty-four hours, and 2) r "screwing" and "unscrewing" of the same on its axis of rotation, to allow its rear pin to faithfully follow the profile of the cam, the latter having the starting point of the first internal profile (24 "c") placed at a higher level than that where both the end point of the aforementioned first internal profile (point 12 where the profiles meet) and the entire cam "b" are placed. in its rotation, at the (lower) level of the "D" plane of the quadrant, it is then brought back, at the moment of its sudden retrogradation, from the lower level of point 24 "d" to the upper level where point 24 "c" is located (from which it started its run), thanks to the aid of a special deflector "E", placed just outside the circumference of the circle of rotation of the cams, starting at the 12 o'clock mark on the dial (and height equal to that of the dial itself) and "going back" as a kind of ramp, up to the initial 24 hours (24 "a"), where it will have reached (and made it reach the pointer) the same upper level where point 24 "c" is placed, thus causing to the hand, during its rotation, also the characteristic o "screwing" and "unscrewing" effect of the same on its rotation axis.