The"SYSTEM OF VARIABLE TRANSMISSION BY NORMAL FORCE ITS IMPROVEMENT"works in a rotation pattern, in a manner similar to a pair of gears.

The continuous variation of the transformation relation is achieved by continuously varying the relation between the lengths of the lever arms. This pattern, as it will be introduced, allows for the variation of the lever arms insofar as, by varying the distances between the rotation axes of both"gears", one alters the distance between the rotation axis of a"gear"and the contact point with the other"gear".

It is impossible to vary the transmission relation with two conventional gears, due to the synchronism between them. On the other hand, in the proposed pattern, it is possible to vary the transformation relation in a continuous manner, once the limitation imposed by the synchronism was resolved by the use of movable locks resembling the ones existing in devices called"ratchets".

Among the several components of this system, the most important ones comprising its original features are the cogwheel, the steering wheel and the set of contact pins, to be introduced next.

Figure 1 shows a top view of the cogwheel (1) which is made of sturdy material in the shape of a disc showing, on one of its sides, a set of cogs (2), with a central circular lowering (3). Each cog has variable width in conformity to an edge (4) in the shape of a curve. Figure 2 shows a side view of the same cogwheel (1) with its cogs (2) forming steps (5) which are perpendicular to the base plan of said cogwheel. In the middle of the figure a dotted line represents the depth of the central circular lowering (3).

Figure 3 shows, from a top view, the steering wheel (6), a part made of sturdy material, also in the shape of a disc, with a ring sharpened surface (7) which is a flat surface near its edge, and with a boss (8) having at the center the flywheel boss (9) where the driving shaft will be coupled. A fixed number of pass-through holes (10) is opened and grouped in circles on said ring sharpened surface.

Figure 4 shows the view of the cutting displayed in figure 3, with the steering wheel (6), showing the ring sharpened surface (7), the boss (8), the flywheel boss (9) and the pass-through holes (10).

Figure 5 shows, from a side view, a contact pin (11), and its head (12). These pins' dimensions must be such that their diameter is slightly smaller than the diameter of the respective pass-through holes, so that they can freely move inside them, but without play. The size of their head should not be larger than the size of the boss (8).

Gearing is done by means of the cogwheel (1) and the steering wheel (6) rotating on parallel plans at a certain distance between them, with the contact pins (11) lodged in their respective pass-through holes (10) and with their heads (12) facing the ring sharpened surface (7), they make physical contact with the cogged surface of said cogwheel. Depending on the direction of the steering wheel's rotation, some of those pins will hit the sides of the steps (5), of the cogs (2), sliding along their respective edge (40) and thus moving the cogged wheel. When the direction of the steering wheel's rotation is reversed, one can notice the ends of the contact pins sliding over the width of the cog, and falling as they reach the step, and by doing so the steering wheel rotates wrongly, not allowing the transmission of movement to the cogwheel, giving rise to a ratchet effect.

Figures 6 to 9 introduce, in a schematized way, the transmission features of the system proposed hereby.

One can notice, in figures 6 and 7, a pattern in which the cogged wheel (1) and the steering wheel (6) are coaxial. The top view of figure 6 shows the cogged wheel (1) without cog details-and the steering wheel (6) with its respective set of contact pins. The same pattern is shown in figure 7 from a side view, displaying the contact of the pins (11) with the cogged surface, being lined up the drive shaft (13) and the driving shaft (14). In such conditions, the transmission ratio is 1: 1, that is, the cogged wheel and the steering wheel rotate at the same angular velocity.

The transmission ratio is proportional to the respective lever arms. The lever arm of the steering wheel is constant and equal to the distance between the center of the flywheel boss and the ideal circular line passing through the middle of the several pass-through holes. On the other hand, the lever arm of the cogged wheel is variable and equal to the distance between the middle of the cogged wheel and the edge point at which the pin makes contact with the cog, plus the radius of the pin.

Thus, the transmission relation is 1: 1 in the above-mentioned pattern, as both lever arms are made equal due to the lining up of both axes.

One can notice, in figures 8 and 9, a pattern whereby the cogwheel (1) and the steering wheel (6) are not lined up. Such dislocation between the driving and drive shafts changes the relation between the lever arms so that the longer the distance between them, the bigger the lever arm of the cogwheel will be and, therefore, the bigger the transmission ratio will be.

The top view of figure 8 shows a cogwheel (1) with no cog details-and part of the central circular lowering (3) hidden, on the other side, by the steering wheel (6) with its set of contact pins. For this system to work efficiently, a device is required (not shown in the figures) which, through a spring effect, will force the pins against the cogwheel's surface.

On the other hand, when an ideal circular line sector passing through the middle of several pass-through holes falls over said central circular lowering (as in figure 8), some contact pins tend to project themselves into this particular lowering, which, due to the steering wheel's rotation, causes a locking or breakage of the pins. To avoid such hindrance, another device is required which temporarily nullifies the spring effect acting over the pins of the sector which is above the central circular lowering of the cogged wheel. Such device (also not shown in the figures) raises the pins of said sector through their heads so that the lower ends of the pins themselves withdraw, taking a position inside the steering wheel, as can be seen in figure 9.

Figure 9 shows a situation scheme in which the cogged wheel (1) firmly connected to the driving shaft (13) is not lined up with the steering wheel (6), which, in turn is firmly connected to the driving shaft (14). One can notice that the contact pins (11) which are more distant from the middle of the cogged wheel keep contact with their cogs, while the contact pins closer to the middle of the same cogwheel can be found in a raised position and retract into the steering wheel. With the rotation of the steering wheel, and due to the action of such mentioned devices, the contact pins perform a reciprocating up and down movement inside their respective pass- through holes.

As can be theoretically deduced, the variation limit in the transmission speed depends on the ratio between the lever arms of the cogwheel and of the steering wheel, and ultimately, on the relation between their respective diameters. For this reason, when higher transmission ratios are required, this system, in a manner equivalent to the conventional systems, can be separated into several pairs of gears in a series, giving rise to a cascading effect.

In figures 10 and 11, the gearwheel (1) is coupled with the motor axle (14), presents itself in the form of a disc, and on one of its sides has a set of teeth (2) and a central circular indentation (3). Each tooth has a variable width according to an edge (4) in the form of a determined curve forming treads (5) perpendicular to the basis plan of said gearwheel. On the mentioned wheel, and concentric to it, a gauze (6) is positioned, also in the form of a disc, with an annular track (7) and with a tappet (8), the gauze's cube (9) being in the center, where the motor axle (13) will be coupled. On said annular track (7), grouped in circumferential distribution, a certain number of passing holes are practiced (10), provided with corresponding contact pins (11), with widened heads (12). The size of those pins must be such that their diameter be a little smaller than the diameter of the passing holes, so that they can move axially and freely, but without play. The gearing is made with the gearwheel (1) and the gauze (6) turning on parallel plans, at a certain distance between themselves, the contact pins (11) being lodged in their respective passing holes (10) and with their heads (12) facing the annular track (7), they make physical contact with the geared surface of said gearwheel. According to the gauze's turning sense, some of those pins will stroke laterally the treads (5) of the teeth (2), slipping along the respective edge (4) and therewith moving the gearwheel. When the turning sense of the gauze is the contrary, the ends of the contact pins are seen slipping over the width of the tooth, falling when reaching the tread, and therewith the wheel turns in vain, ceasing to transmit movement to the gearwheel, generating the ratchet effect.

As can be deduced theoretically, the variation limit in the transmission velocity depends on the ratio between the levee arms of the gearwheel (1) and of the gauze (6) and, in last analysis, on the relationship between their respective diameters. For that motive, when higher transmission ratios are desired, this system, in an analog manner to the conventional systems, can be broken down into several pairs of gears in series, realizing the cascading effect.

Another materialization of the transmission system, which is the object of the present invention, comes about through its use without a clutch as well as without the use of converter, a situation where transmission ratios above 10: 1 are obtainable (Figure 12).

In order to have the system operate with no clutch, we only alter the link between the axles, in which case toothed wheel (1) remains static, in a fixed position, rotating only flywheel (6), which is not directly linked to motor axle (14).

The direction of the rotation in driving axle (13) will be determined by the design of steps (5) of the wheel (clockwise and counter-clockwise).

The rotation direction, in such case, does not depend on the entrance axle because it is not linked to the flywheel, but rather to a ring or a bearing, which, upon leaving the center, causes an indirect rotation on the flywheel. Such effect appears and gradually increases upon its leaving the zero (central) position, then reaches maximum rotation when it is dislocated until its outer limit.

The flywheel's (6) and driving axle's rotation (13) will always be in the same direction, previously determined by the steps (5) of the toothed wheel, even when the rotation of the driving axle is reversed (14). This is due to the fact that the driving axle, when centered, causes a ring (15) to rotate-like in a bearing-which involves the flywheel (6), either inside or outside, however exerting traction neither on such flywheel nor on the driving axle.

After leaving the central position, this ring (15) produces a so-called'cam effect.'The toothed wheel, acting as a ratchet brace, only allows the rotation of the flywheel (6) in the direction selected by the steps, and eventually activates the driving axle (13), which, for its turn, the larger the distance is from central position, the faster it eventually rotates in comparison to the driving axle (14). To switch on the flywheel with an excentric rotation, as far as the driving axle is concerned, we use a joint of the'Oldham'or'Zara'types.

The"SYSTEM OF VARIABLE TRANSMISSION BY NORMAL FORCE ITS IMPROVEMENT"can be potentially applied to the automotive and bicycle industry and can work with or without clutch, in substitution for conventional gear shifts, as well as to any mechanical machine or equipment where it is required to control the speed of rotation and torque, such as in lathes, mills, etc.