WO2002025141A1

WO2002025141A1 - Movement transforming device

Info

Publication number: WO2002025141A1
Application number: PCT/FR2001/002902
Authority: WO
Inventors: Antoine Fuster
Original assignee: Antoine Fuster
Priority date: 2000-09-21
Filing date: 2001-09-18
Publication date: 2002-03-28
Also published as: CN1462348A; EP1319141A1; FR2814212B1; AU2001291950A1; FR2814212A1

Abstract

The invention concerns a device (2) comprising a slide (9) in the form of a rectangular frame, mobile in translation along its major axis (10), and comprising on the inner surface of each of its major sides a rack-like toothing (14. The slide (9) is engaged about a wheel (15) wedged on a shaft (6) and having a toothed sector (16) meshing successively with one or the other of the two sets of teeth (14) along the moving direction of the slide (9). The sets of teeth (14) have a curvature, or an inclination relative to the major axis (10) of the slide (9). The toothed sector (16) of the wheel (15) has, over its length, a variable distance relative to the geometrical axis (17) of the shaft. Thus a variation in the relationship between the translational speed of the slide (9) and the rotational speed of the shaft (6) is obtained. Said device is applicable to heat engine, particularly spark ignition engines, the slide (9) being linked at least to a piston (5).

Description

Motion transformation device

The present invention relates to a movement transformation device, more particularly a mechanical device for the transformation of an alternating rectilinear movement or into continuous rotary movement, or vice versa. This device is applicable more particularly, but not exclusively, to the production of heat engines, for the conversion of the reciprocating rectilinear movement of at least one piston, movable axially inside a cylinder, into a movement of continuous rotation d '' an output shaft, replacing a conventional crankshaft.

By French Patent No. 2,093.1 19. in the name of the Applicant, a device is already known for transforming an alternating rectilinear movement into a continuous rotary movement or vice versa. This known device mainly comprises a slide in the general shape of a rectangular frame, movable in translation along its major axis, and comprising on the internal face of each of its long sides a toothing forming a rack. The frame-shaped slide is engaged around a wheel, wedged on a shaft which crosses said slide. The wheel has a toothed sector, with the same module as the two racks and thus being able to mesh with one or the other of these racks.

Thus, when the slide describes an alternating rectilinear movement along its major axis, the toothed sector of the wheel is alternately engaged with one of the racks (for a direction of movement of the slide) and with the other rack (for the direction opposite movement of the same slide). Preferably, means are also provided for linking the displacements of the slide to the rotation of the shaft, when the toothing of the wheel is no longer engaged with one or the other of the racks of the slide, this is ie in the two end positions of this slide.

In this way, the reciprocating rectilinear displacements of the slide ensure a continuous rotation, in an invariable direction, of the shaft on which the wheel is wedged with toothed sector, and the reverse transformation, that is to say the conversion of a continuous rotary movement of the shaft in a reciprocating rectilinear movement of the slide, is also easily conceivable. It is therefore possible, by associating with this slide a piston, or preferably two opposite pistons arranged in alignment with one another, to produce a heat engine and in particular an internal combustion engine, of particularly simple and economical design, in which the number of moving parts is greatly reduced (in comparison with a traditional motor).

In particular, in such a heat engine, the or each piston can be linked directly to the slide, without the need for articulated connecting rods, and the crankshaft of a traditional engine is removed, and replaced by a simple rectilinear shaft for output of the movement. In addition, the articulated connecting rods being replaced by simple rods connecting each piston to the slide along the axis of this piston and the slide, and always acting in the direction of said axis, the wear of the pistons is considerably reduced, and any ovalization of the cylinder bore is prevented. Finally, in such an engine, the lubrication is simplified, the oil remaining in the center and no longer having to be replaced.

However, in the embodiments described by the aforementioned French patent No. 2,093.1 19, or by other similar documents such as French patent application No. 2,451,518, the two racks of the slide are rectilinear and parallel to the axis of this slide. Thus, the speed of translation of the slide, in either direction of its reciprocating rectilinear movement, is always proportional (in a constant ratio) to the speed of rotation of the output shaft. In particular, the ratio between the speed of translation of the slider and the speed of rotation of the shaft is not modified towards the end of travel positions of the slider, therefore of the pistons linked in translation to this slider. It follows that the engine operates with jerks, and that phenomena such as explosion and compression, specific to a heat engine, are not taken into account in the transformation of the movement. Consequently, the operation of the engine is not optimized, so that such an engine still lacks power and flexibility, which explains why, until now, this type of engine has not found applications. practical, despite its undeniable advantages.

Also known, from document WO 96/16282 (in particular FIG. 4), a movement transformation device for a piston engine, of complex structure with oscillating levers and connecting rods, and also including curved racks which cooperate with pinions and with rotary cams, these racks themselves being mounted to oscillate. Such a device, very complex, remains far from the principle of transformation of movement to which the present invention relates, and its oscillating racks, designed as separate parts, have nothing in common with racks or teeth formed in the opening of 'a slide.

The present invention aims to avoid the drawbacks previously exposed, by providing an improved movement transformation device, of the type here concerned, allowing an adaptation of the ratio between the speed of translation of the slide and the speed of rotation of the shaft, and allowing thus, in the context of its preferential application to the production of a heat engine, an optimization of the engine, while retaining a simple, rigid and economical structure.

To this end, the subject of the invention is essentially a device for transforming an alternating rectilinear movement into a continuous rotary movement, of the kind previously indicated, in which the two teeth or racks of the slide have a curvature, and / or a inclination with respect to the major axis of the slide, so that the distance from each toothing to this axis varies over the length of this toothing, while, correspondingly, the sector-shaped toothing of the wheel has, along its circumferential length , a variable radial distance from the geometric axis of the shaft, so as to obtain a variation of the ratio between the speed of translation of the slide and the speed of rotation of the shaft, over all or part of the stroke of the slide.

According to an exemplary embodiment of the invention, the two teeth of the slide have a curved appearance, in particular with a central portion further from the major axis of the slide than the end regions.

According to another embodiment of the invention, the two teeth of the slide form rectilinear or substantially rectilinear racks, parallel to each other but inclined relative to the major axis of the slide. As for the wheel with toothed sector, this can be an eccentric wheel relative to the shaft which carries it, the eccentricity of this wheel allowing its toothing to have, over its circumferential length, a radial distance varying by relation to the geometric axis of the tree. Thus, in a way, the device according to the invention makes it possible to vary, by adapting to the needs of each particular case of application, the "lever arm", therefore also the torque, according to which the slide sets in rotation the tree which carries the toothed sector.

Such a movement transformation device is applicable to the production of a heat engine, in particular an internal combustion engine, comprising at least one piston mounted to slide in a cylinder secured to a casing in which the device is housed, the piston being linked , in its reciprocating sliding movement, with the slide of the device, to drive an output shaft in continuous rotation. Preferably, in this application, two opposite coaxial cylinders, arranged on either side of a central casing, respectively contain two pistons linked to the opposite ends of the slide.

In the context of this application to a heat engine, the device which is the subject of the invention makes it possible to adapt very significantly, during the engine operating cycle, the "lever arm" (therefore also the force) according to which the slide rotates the output shaft, via the toothed sector. The moments can thus be changed, in the course of the engine cycle, to optimize its intrinsic efficiency, which no traditional engine with connecting rods and crankshaft allows.

The determination of the teeth can be such that this "lever arm" is increased at the time of the explosion in a cylinder, in order to recover all of its power as well as possible, and that the movement of the slide is slowed down at the end of the stroke, in order to reduce the jolts while increasing the power during compression in the opposite cylinder.

We can also consider the opposite, that is to say provide a "lever arm" smaller at the start of the cycle, and longer at the end of the cycle (or end of stroke of the slide).

It is also possible to envisage practically identical "lever arms" at the start and end of the cycle or stroke, and to increase the "lever arm" in the middle portion of the slide stroke. These various variants, and others still, can be determined by calculation, in a computer-aided design process, in order to adapt each engine according to its specific use, and especially according to the characteristics of the expansion or of the combustion or the propagation of the explosion, more or less brutal. It will be noted that such an adaptation is done in a simple and economical manner, by the simple calculation of the teeth and their corresponding machining, without additional parts or special regulation system.

The action of the cooperating teeth of the device is advantageously completed, in the end-of-travel positions of the slide, by the action of the means then linking the movements of this slide to the rotation of the shaft. These means may consist of at least one flange of circular shape wedged on the same shaft as the toothed wheel, and comprising at least one profiled groove located opposite a face of the slide, the or each groove being provided to cooperate with at least one stud or lug that the slide comprises at each of its ends, the profile of the or each groove being such that it ensures continuity in the rotation of the toothed wheel when the slide reaches the end of its travel. It is preferably provided here, in the or each flange, two profiled grooves which cooperate respectively with two nipples or lugs of the slide, these two nipples or lugs being offset relative to each other, in their positions and their instants d 'engagement in the corresponding grooves. Thus, the possible clearances are compensated for, and the jolts are eliminated, at the end-of-travel positions of the slide, therefore also of the pistons.

Overall, this gives an engine of optimized structure and operation, with a gain in power and flexibility.

The invention will be better understood with the aid of the description which follows, with reference to the appended diagrammatic drawing representing, by way of examples, some embodiments of this movement transformation device, in the case of its application to a heat engine:

Figure 1 is a longitudinal sectional view of a two-cylinder heat engine, comprising application of the movement transformation device according to the present invention; Figure 2 shows, on an enlarged scale, the movement transformation device of the motor of Figure 1;

Figure 3 is a detail view, similar to Figure 2, showing a variant of this movement transformation device. FIG. 1 shows the device according to the invention, designated as a whole by the reference 2, applied to the production of a heat engine having two opposite coaxial cylinders 3 (one of which is only partially represented), arranged on either side of a central casing 4, and integral with this casing 4. The movement transformation device 2 is housed in the casing 4; it converts the reciprocating rectilinear movement of two pistons 5, slidably mounted respectively in the two cylinders 3, into a continuous rotary movement of an output shaft 6, which crosses the casing 4. As an internal combustion engine , each cylinder 3 comprises, opposite the casing 4, a spark plug 7 located in a combustion chamber 8, delimited by the cylinder 3 and the piston 5. Each cylinder 3 also includes intake and d exhaust, here not detailed.

The device 2 mainly comprises a slide 9 in the form of a rectangular frame, mounted inside the casing 4 and movable in translation, in the direction of its major axis 10, being guided by rectilinear slides 1 1, fixed to the inside of the casing 4 on either side of this slide 9. It will be noted that the major axis 10 of the slide 9 coincides with the axes of the cylinders 3 and of the pistons 5.

In the case of the present application, the slide 9 is coupled by its ends, in the extension of its major axis 10, to two opposite rods or connecting rods 12, located in alignment with one another. Each rod or connecting rod 12 slides in a bearing 13, located at the corresponding end of the casing 4, and it extends inside one of the cylinders 3, where it is itself coupled to the corresponding piston 5. The slide 9 comprises, on the internal face of each of its two long sides, a toothing 14 forming a rack, the particular conformation of the toothing 14 being described below.

The output shaft 6, which passes through the central opening of the slide 9, carries a wheel 15 wedged on this shaft 6, and located inside said opening. The wheel 15 has at its periphery a toothing 16, similar to the toothing of a pinion but extending only over a sector of this wheel 15; the rest of the periphery of the wheel 15 is devoid of teeth, and may appear as a smooth surface. The teeth 16 of the wheel 15 have a module equal to that of the two teeth 14 of the slide 9, so as to allow engagement with one or the other of these two teeth 14, the teeth 14 and 16 having the same number teeth.

As shown in more detail in FIG. 2, the two teeth 14 of the slide 9 do not form rectilinear racks, but have a generally curved appearance, with a central portion further away from the major axis 10 of the slide 9.

In direct relation to the above, the wheel 15 is eccentric with respect to the shaft 6 which carries it, so that, if we consider the radial distance from a toothing point 16 to the geometric axis 17 of the shaft 6, this distance is variable, passing for example from a minimum (at one end of the toothing 16) to a maximum (located at an intermediate point, or towards the other end, of this toothing 16).

It follows that during the operation of the engine, the two teeth 14 of the slide 9 alternately engage with the teeth 16 of the wheel 15, the operation being established as follows: The two pistons 5 being alternately repelled by explosions from the candles 7, they print on the slide 9, by means of the rods or connecting rods 12, an alternating rectilinear movement along the major axis 10 of this slide 9. The toothing 16 in the form of a sector of the wheel 15 thus being successively in taken with one and the other of the two teeth 14 of the slide 9, the wheel 15 and the shaft 6 are rotated continuously.

During a back or forth movement of the slide 9, the teeth 16 of the wheel 15 rolls on one of the teeth 14 of the slide 9, the contact point of these teeth being variable and also having a radial distance variable with respect to the geometric axis 17 of the shaft 6. This results in a variation in the ratio between the instantaneous speed of translation of the slide 9, on the one hand, and the instantaneous speed of rotation of the shaft 6, d 'somewhere else. As is easily understood, the choice of the shape of the teeth 14, and of the eccentricity of the wheel 15, makes it possible to adapt this gear ratio, over the entire travel of the slide 9 therefore pistons 5, and in particular towards the end positions of these pistons 5.

In addition, to ensure proper operation at each end of travel of the slide 9, the wheel 15 is bordered, on either side, by two circular flanges 18, between which the slide 9 is also included. The flanges 18 comprise each two profiled grooves 19 and 20, parallel to each other, the two grooves 19, 20 of one of the flanges 18 being located in correspondence with the two grooves of the other flange. The slide 9 has, on either side of each of its ends, two pins or lugs 21 and 22, designed to engage respectively in the two profiled grooves 19 and 20 of the slide 9, at each end of travel of this slider 9, that is to say each time the toothing 16 of the wheel 15 meshes with neither of the two toothing 14 of the slider 9. By these arrangements, the displacements of the slider 9 remain, at all times, related to the rotation of the wheel 15, which also means that the displacements of the pistons 5, towards their end-of-travel positions, remain linked to the rotation of the output shaft 6, in particular in the position shown in FIGS. 1 and 2 .

Preferably, in order to ensure an even more flexible operation of the device 2, the two pins 21, 22 provided on the slide 9, at each end, are offset relative to each other, in their positions therefore also in their instants of engagement in the corresponding grooves 19, 20, so as to better absorb any play and jolts at each passage from one toothing 14 to the other, and thus to suppress parasitic resonances.

FIG. 3, in which the elements corresponding to those described above are designated by the same references, shows a variant of the movement transformation device 2 object of the invention. In this variant, the slide 9, still in the form of a substantially rectangular frame, has on the internal face of its two long sides, respectively two teeth 14 forming a rack. The two teeth 14 here form rectilinear racks, which are parallel to each other, but whose directions form a certain acute angle relative to the direction of the major axis 10 of the slide 9. In correspondence with this conformation of the two teeth

14, the wheel 15 has a toothed sector 16 which, thanks to the eccentricity of this wheel 15 relative to the geometric axis 17 of the shaft 6, has an increasing radial distance (measured from the axis 17) , from one end to the other of this toothed sector 16.

Thus, during operation, each rectilinear toothing 14 of the slide 9 successively engages the toothed sector 16 of the wheel 15, and the point of contact of the teeth has a variable distance, for example increasing or decreasing, with the axis 17 of the shaft 6, so that the rotation of this shaft 6 is gradually slowed down or accelerated, between one end of travel and the other.

Furthermore, in a manner here not described in detail, the whole of the movement transformation device 2, enclosed in the casing 4, operates in an oil bath. We would not depart from the scope of the invention, as defined in the appended claims:

- by modifying constructive details, such as the external shape of the slide 9;

- by adapting the shape of the two teeth 14 of the slide 9, according to the desired movement transformation law;

- by modifying the number of grooves 19, 20 and corresponding lugs 21, 22;

- by using any equivalent of the mechanical organs described, in particular by replacing the teeth 14 and 16 with a system of ramps (instead of the teeth 14 of the slide 9) and of cams (replacing the toothed sector 16);

- in the context of the application of the device to a heat engine, by juxtaposing two or more similar devices 2, which will then be linked by an output shaft

6 common, so as to produce a motor with more than two cylinders 3, in which case the positions of the toothed sectors 16 of the wheels 15 of the different unitary devices are advantageously offset, to ensure the regularity of the drive in continuous rotation of the shaft 6; by providing the same device 2, the operation of which is "reversible", for the reverse transformation of a continuous rotary movement into a reciprocating rectilinear movement, for example for the constitution of a piston compressor; more generally, by using this device for all devices, machines and equipment requiring a conversion from reciprocating rectilinear movement to continuous rotary movement, or vice versa.

Claims

1 - Device for transforming an alternating rectilinear movement into a continuous rotary movement, or vice versa, mainly comprising a slide (9) in the general shape of a rectangular frame, movable in translation along its major axis (10), and comprising on the internal face of each of its long sides a toothing (14) forming a rack, the slide (9) being engaged around a wheel (15), wedged on a shaft (6) which crosses said slide (9), the wheel (1 5) having a toothed sector (16), with the same module as the two racks (14) and capable of meshing with one or the other of these racks (14), so that, when the slide (9 ) describes a reciprocating rectilinear movement along its major axis (10), the toothed sector (16) of the wheel (15) is alternately engaged with one of the racks (14), for a direction of movement of the slide (9) , and with the other rack (14), for the opposite direction of movement of the same slide (9), means (18 to 22) being preferably provided for linking the movements of the slide (9) to the rotation of the shaft (6), when the toothing (16) of the wheel (15) does not is no longer engaged with one or the other of the racks (14) of the slide (9), that is to say in the two end positions of this slide (9), characterized in that the two teeth or racks (14) of the slide (9) have a curvature, and / or an inclination relative to the major axis (10) of the slide (9), so that the distance from each toothing (14) to this axis ( 10) varies over the circumferential length of this toothing (14), while, correspondingly, the toothing (16) in the form of a sector of the wheel (15) has, along its length, a variable radial distance from the 'geometric axis (17) of the shaft (6), so as to obtain a variation of the ratio between the speed of translation of the slide (9) and the speed of rotation of the shaft (6 ), over all or part of the travel of the slide (9).

2 - movement transformation device according to claim 1, characterized in that the two teeth (14) of the slide (9) have a curved shape, in particular with a central portion further away from the major axis (10) of the slide (9) as the end regions. 3 - movement transformation device according to claim 1, characterized in that the two teeth (14) of the slide (9) form rectilinear or substantially rectilinear racks, parallel to each other but inclined relative to the major axis (10) of the slide (9).

4 - movement transformation device according to any one of claims 1 to 3, characterized in that the wheel (15) with toothed sector (16) is a wheel (15) eccentric with respect to the shaft (6) which the door. 5 - Movement transformation device according to any one of claims 1 to 4, characterized in that the means, provided for linking the movements of the slide (9) to the rotation of the shaft (6), in the positions of end of stroke of the slide (9), consist of at least one flange (18) of circular shape fixed on the same shaft (6) as the toothed sector wheel (15, 16), and comprising at least one profiled groove (19, 20) located opposite one face of the slide (9), the or each groove (19, 20) being designed to cooperate with at least one stud or lug (21, 22) that the slide (9) comprises at each of its ends, the profile of the or each groove (19, 20) being such that it ensures continuity in the rotation of the toothed wheel (15, 16) when the slide (9) reaches the end of its travel.

6 - movement transformation device according to claim 5, characterized in that there are provided, in the or each flange (18), two profiled grooves (19, 20) which cooperate respectively with two pins or lugs (21, 22) of the slide (9), these two pins or lugs (21, 22) being offset relative to each other, in their positions and their engagement times in the grooves (19, 20) corresponding.

7 - Movement transformation device according to any one of claims 1 to 6, characterized in that it is applied to the production of a heat engine, in particular an internal combustion engine, comprising at least one piston (5) mounted sliding in a cylinder (3) integral with a casing (4) in which is housed the device (2) for transforming movement, the piston (5) being linked, in its reciprocating sliding movement, to the slide (9) of the device (2), for continuously driving an output shaft (6). 8 - Application of a movement transformation device to a heat engine according to claim 7, characterized in that two opposite coaxial cylinders (3), disposed on either side of a central casing (4), respectively contain two pistons (5) linked to the opposite ends of the slide (9).