FR2779406A1 - Saddle support tube for bicycle - Google Patents

Abstract

The bicycle saddle support tube has a sleeve in which slides a sprung piston attached to the saddle mounting. An intermediate skirt fixed in the sleeve forms the upper stop. The lower stop is mounted on the piston by a lower closure. The length of the skirt determines the piston movement range and a tilting ring transmits lateral adjusting forces to the piston.

Description

-1- Telescopic bistable structure with translational capacity

  to assume the positions of any device requiring two sequential stopping and retroversion points of any orientation in space, depending on the application of alternative forces acting in the direction of the movement generated, combined with the effect of lateral control pulses. Considered in a concept of translation directed along the vertical or an oblique upright the bistable structure lends itself particularly to the supply of two levels of attitude to any device belonging to the field relating to seats and assimilated as a cycle saddle for which the structure s '' integrated into the frame and replaces the rod

  saddle fitted to this family's vehicles.

  The bistable telescopic structure is shaped according to a cylindrical or pseudo-cylindrical architecture. It consists of a hollow and blind piston sliding in a blind sleeve, a compression spring which is interposed between these pipes and an intermediate jacket immobilized in the sleeve conforming to the interior of the latter. The sliding sliding of the piston is guided in the jacket between two states of stability separated by its length, materialized in the sheath, on one side by an obstruction plug which provides support for the spring and this jacket, on the other side by the free end of the same shirt. The bistable structure comprises a self-lubricated ring which contributes to the sliding of the piston and which is in contact with the free end of the sleeve by their common faces, which each have a bevel according to two angularly differentiated symmetrical declivities allowing a tilting of the ring, in the plane of symmetry with respect to the point of application of the control pulse. The lateral control, of negligible value with regard to the alternative animation force, is driven into the deployed position of the piston by the tilting of the ring; the

  persistent result of its action is canceled by a similar tilt in the opposite direction.

  In the conjuncture which refers to the seatpost, the force generating the alternative translation is identified with the weight of the user cyclist applied to the saddle then subtracted from it and thereby restored in the ascending opposite direction by the detent spring and whose control comes from the will of the cyclist. The lateral impulse effect results from the collateral displacement of the area of application of the translational force on the saddle along the plane of symmetry of the structure merged with the sagittal plane of the cycle, its

  control remains subject to the will of the cyclist.

  -2 - The collateral force causes the tilting ring to tilt, which constitutes the member for transmitting a lateral impulse, thus the imbalance of the ring operates a splash which assembles the piston with the top of the liner intermediate; in this state the piston is representative of the raised level of the saddle with which it is linked by a suitable fastener. The resulting device is capable of ensuring two saddle heights when using a cycle. It replaces the traditional rigid seatpost, which supports the disadvantage of an empirical height adjustment and ill-suited to the cyclist, who has the choice: _ either a high adjustment, optimized for its measurement, reconciling drastic pedaling

and attractive traffic.

  _ or a low adjustment, accommodating, which provides comfortable stops on the ground. _ either a median situation leading to a mediocre compromise, to compensate for the shortcomings generated by the first two solutions; namely a precarious balance when stopped, with uncertain support on one leg for optimal adjustment and a painful pedaling inconvenience due to its persistence for those who allow both

feet on the ground.

  _ after a previous halt there remains the possibility of manually adapting the

  seat height in traffic circumstances.

  The device according to the invention allows a low level of saddle for the stop phases or in slow and congested circulation and a raised level, in harmony with the stature of the cyclist for normal circulation. Each of these two states is available at the

  less solicitation of 'interested.

  Its general appearance is similar to a traditional seatpost in which are found the fixed part conventionally linked to the frame of the cycle and the sliding movable part secured to the saddle and its fastener, which is if necessary adapted to satisfy the fixation. According to a fundamental characteristic, the mobile part slides in the fixed part made up of the tubular sheath between two predefined limits for high stabilities

  and low in active circulation with the option of remaining at will on each of them.

  The high position is reached immediately when the user abandons the cycle and in particular when, starting from low use, he straightens up and relieves the saddle of his weight by standing for an instant on the pedals for the ascent time of the saddle which moves the compression spring internal to the device and which relaxes. The user then sits back on the saddle in minimal and natural glide of the body towards the rear and causes by the movement thus sketched the lateral control whose effect determines the

  splashing in the high position of the saddle.

  The return to the low position follows from the preliminary initiation of a relief of the saddle from the weight of the user accompanied by an imperceptible opposite shift of the body towards the front, which uncouples the piston from the dormant part. of the device; the low position is obtained by the action of the weight of the user sitting down and compressing the spring. A stopper retains this state which corresponds, during the installation adjustment, to the height allowing the cyclist seated on the saddle the access of his feet camped on the ground to

  the stop in the rest and safety position.

  This lower stop is the seat that the piston finds on the lower shutter, removable for reasons of construction and mounting of the device, provided with a specialized cell for retracting the sputtering means. The jacket is immobilized by a mesh in specific notches of the shutter arranged on either side of the cell. Aliasing of the jacket and lower shutter assembly can replace the notch system. The lower end of the compression spring is also located

  immobilized at the level of the lower shutter to oppose its possible rotation.

  The length of the inner sleeve to the sleeve and intermediate to the dormant and movable parts, is determined for the size of the user when the saddle is in the upper position, the sputtering performed corresponds to a high re-entrant stop. The uncoupling of the organs, preliminary to the descent of the saddle, results in a tiny rise of the latter to the maximum authorized of the piston stroke, which guarantees an internal cable to the spring of flexible and inextensible design. The cable is fixed in the piston thanks to an elastic and expansible upper shutter, blocked by its compression due to the tightening of a nut accessible from the outside before mounting the seat clamp. The cable plays the role of a high ejection stop, it is stretched when the maximum stroke is reached. This is established from its low point of retention using

  a concentrically acting compression clamp formed in the lower obturator.

  The upper shutter as its lower equal keep the spring fixed by constraining its ends which are formed to engage in openings

in the shutter elements.

  The piston tube also slides in the ring supported on the top of the sleeve; their common contact surfaces have an obtuse angle bevel to reduce the height occupied by this system, in inverted V or not. A slight angular difference exists between the contiguous gradients, which causes a weak and sufficient tilting of the ring towards the rear when the piston reaches its deployment limit, with for consequences its deviation and the introduction of the means of sputtering. that can

  look like a claw in a notch in the front of the top of the shirt.

  The notch and the claw presented in their simplest form can assume variations in appearance and number which are most suitable for ensuring effective interpenetration.

  and reliable as much as the ease of their declabotage.

  According to particular embodiments: _ The expandable element of the upper shutter can be of one-piece conformation or the result of a stack of fragments sized to the parts in contact. _ The tilting sliding ring can be constrained to the sheath by an adhesive bandage, self-sealing and remaining flexible such as an elastomeric rubber, to ensure its homogeneity and consequently its solidity, from a version perspective.

stripped down.

  _ The tilting ring can be contained in a cylindrical socket overhanging the sheath, constituted by an imperfectly screwed tightening nut ring

  on a second so-called retaining ring, attached and totally subject to the sheath.

  _ The tilting ring can be packaged in a space arranged between the nut ring as before and the sleeve, the machined shape of which

  a certain complexity of shaping includes both the retaining ring and the bevelling.

  _ The sheath can include the retaining ring specifically as a part of revolution for which the beveling is carried out separately on an additional support ring added and totally subject to the sheath tube to melt

with him.

  The solution which seems to prevail on the economic level, apart from the stripped version is that which refers to the retaining ring added, it is therefore the subject of the description and the associated drawings in Figures 1 and 2 are also held. However, capable of reflecting a particular aspect of the treatment that can be envisaged, this solution may give rise to inclinations of modifications or different approaches to implementation which remain within the scope of the invention. Also the description includes the development of parallel equivalences applicable to any field assimilating the advantage of a base

  bistable alternative, of free access in level as in duration without contribution of motorization.

  It therefore evolves from an apparent complexity of design, emanating from a simple principle, towards a finality which inclines to the elimination of the artifices of implementation, -5 -

  relatively heavy with industrial implications.

  In the last three particular embodiments, the tightening nut ring is able to be strengthened on the sliding ring by complementary screwing of a fraction of a turn. To this end, the nut ring is provided with a boss arranged on the inner surface of its collar so that the generated prominence rests on the tilting axis to ensure the maintenance of the ring in its embolture in bistable session and exerts at the end of the screwing a formal support on the latter perpendicular to the rear panel of the bevel, which determines and retains its tilting. The nut ring has a small lever accessible under the front of the saddle to facilitate maneuvering in circulation. The resulting arrangement is suitable for equipping MTB type cycles in particularly demanding use requiring temporary total rigidity of the seatpost and is also appreciated for operating maneuvers.

  service or transport of any type of equipped cycle.

  _ The intermediate shirt which serves as a top stop can be a piece of

  length specially suited to the size of the user or approximate at most to the desired value.

  _ It can be divided into several sections, a first basic element corresponding to a decidedly small size (bicycle for young teenagers for example). The customization of the height is accomplished following the addition of one or more additional elements20 of unit length introduced by the bottom of the rod after removal of the obturator plug; - the shape of their ends is crenellated or notched so to be embedded

  in just sliding, following and in the basic element, raising it to form an inert coherent whole, particularly in rotation. This arrangement is suitable for the equipment of cycles intended to "grow" with their junior users as well as to provide a "tailor-made" article from standard elements. The addition or subtraction of such additional elements is accompanied by the lengthening of the cable.

  The accompanying drawings illustrate the invention:

  Figure I shows in section the device according to the invention in the low position.

  Figure 2 shows in section the device in the high locked position.

  Figure 3 specifies in partial section the fixed bevelled machined part of the device.

  Figure 4 specifies in partial section the fixed beveled fixed part of the device.

  Figure 5 sketch in partial section the bevelled parts in stripped version.

  Figure 6 sketches the locking system of the saddle in the high position.

  Figure 7 is a partial vertical section of the locking system with anchoring -6 - lever position and Figures 7A and 7B show its free top view then blocked. Figure 8 partially shows in exploded view the internal part of the fraction

of the device.

  Figure 9 breaks down the distribution of the complementarity of the angles involved in

  the beveling of the two elements face to face of the tilting system.

  Figure 10 symbolizes the impact on one or the other element of the subtraction of a

angle allowing tilting.

  Figure 11 symbolizes the impact on one or the other element of the addition of an angle

authorizing the rotation.

  FIG. 12 and its derivatives 12-A and 12-B show the possible combinations for the production of the thrust spring according to the principles put forward for the

specificity encountered.

  Figure 13 deals with a particular profiling of the tubes of construction of the advanced device under the visible aspect on section A and the sections Bet C. Figure 14 and its lightened derivatives 14-A to 14-D are an idealized and realistic form of

the seat post completed.

  Figure 15, lightened and its companions 15-A to 15-C, are a replica of the

  Figures 14 with a degree of idealization taking an additional step.

  With reference to these drawings, the device (Fig. I) comprises a tubular sheath (l) closed at the lower end, dimensioned to fit into the space reserved for the seatpost as part of a cycle and based on lower level suitable for the user during the stop phase. The sheath (1) contains a compression spring (2) with coaxial thrust in a movable and hollow piston (3) of which the saddle and its fastener (4) are integral, up to the height defined for the upper position materialized by the jacket (5) intermediate between the sleeve (1) and the piston (3) and therefore providing guidance to the piston. The latter also slides through the self-lubricated ring (8) which is in unstable support on the top of the sleeve (1) by the bevelled shape of their common faces and the angular adjustment of the bevels knowingly and slightly differentiated. The relative tilting resulting memorizes the state of stability of the saddle adopted by the cyclist according to the circumstances of circulation by causing or not the cramping of the claw (3a) extending the foot of the tube (3) which takes place in a notch ( 5a) top on the front of the shirt (5) (Fig. 2 and 4) in dynamic sequence. The claw (3a) also disappears in the cell (6a) when it meets the front of the low stop (6) which is offered to the

  piston (3) on top of the shutter (7) in static sequence (Fig. 8).

  -7 - The torque formed by the top of the sheath (1) with the base of the ring (8) rests on the beveling of their common bearing faces considered as the superposition of two obtuse angles decomposable according to circular quadrants revealing two vertically symmetrical semicircles IMJ and INJ (Fig. 9), each consisting of the addition of a quadrant of angular value% / 2 and a quadrant resulting from the juxtaposition of two complementary angles a and a 'each belonging to one of the elements: the sheath (1) and the ring (8). In this state the assembly obtained is neutral, the total angular sum of the assembly is 2x. The interposition of a very small angle p between a and a 'creating a physical vacuum, breaks the stable equilibrium achieved at the junction of the two elements (1) and (8) and defines a tilting mode differ depending on whether the term p comes in

  addition or subtraction of a or a '.

  A first possibility consists in a swing perpendicular to the edges x, y of the angles of the bevels when P is subtracted from the complementarity a + a 'and the orientation of the bevels is that of the edges merged at the point O perpendicularly

  in the sagittal plane of the cycle (Fig. 10).

  A second possibility allows partial rolling of the ring (8) on the bevelled blanks of the sheath (1) in a direction parallel to the edges of the bevels; this bearing

  located from front to back of small amplitude corresponds to an oscillation of the ring (8).

  The second possibility arises when p is in addition to the complementarity a + a 'and the orientation of the bevels remains perpendicular to the respective edges pointed at O and O' which align along the sagittal plane of the cycle (Fig. 11). The reasoning remains valid for a beveling of the bearing faces whose tip would be

facing down.

  The description and its drawings are based on the subtractive tilting mode. The fluctuations of the ring (8), with the edges arranged perpendicular to the sagittal plane evolve in a space confined by the female ring (11), like a tightening nut, incompletely screwed on the male ring (12), which holds is attached to the sheath (1), and immobilized in position permanently and permanently. The threaded part of the retaining ring (12) is provided with a notch (12a) on a fraction of its upper periphery, distributed equally on either side of the sagittal plane of the cycle in order to ensure sufficient angular movement. to complete the tightening of the ring (l 1)

  when completing the screwing rotation (Fig. 6).

  - 8 - A boss (t1 a) judiciously installed on the internal shoulder of the collar of the ring (11) nut causes and retains the inclination of the ring (8) and consequently that of the piston (3). A small lever (15) firmly plugged into a peripheral point of the ring (11) is located so that the inserted end protrudes inside of it and opens into the space cleared by the notch made on the upper part of the retaining ring (12) for sweeping the extent AB of the previously defined angular movement. This arrangement, which is manually accessible in traffic, conditions the extent of the screwing on completion, eliminating the risk of excessive blockage

  of the sliding ring or on the contrary the unexpected unscrewing of the ring (1) nut.

  Figure 6 summarizes the example of a notch in the retaining ring (12) such that a clearance of about 90 is assigned to the lever (1 5) passing from position A to position B. This generates the screwing the ring (l1) nut accompanied by the descent of the boss (11a) of the order of 0.25 mm for a standardized fine thread of M 30 x I of the rings (11) and (12) concerned. The progression of the boss downwards, when the lever (15) reaches point B cancels the inter-bevel backlash of the same order which exists when the ring (8) is centered on the sheath (1) and that the lever ( 15) is in position AA this lever is incorporated a ball anchoring system or similar suitable for hardening of the lever (15) in the extreme positions concretized by cavities or grooves made on the interested part of the periphery of the ring ( 8) in order to prevent position disparities (Fig. 7, 7-A, 7- B). If particular reasons are discovered to oppose the existence of a controller, its visible part may be abandoned but it must

  remain the internal end in order to preserve the limitation of rotation of the ring (11).

  For the clarity of the description only the boss (11a) was mentioned in its

  role of system blocker (Fig. 6). It must also ensure the permanence of the vertical fixity of the ring (8) during sliding. To this end, the task is shared with a second boss (1b), diametrically opposite on the collar, limiting itself to providing a symmetrical contact point directly above the tilting edge x, y of the ring ( 8). The upper surface of the ring (8) is also bevelled on the half-face oriented towards the front along an oblique plane (8a) having the same characteristics as the lower bevel (8b). The usefulness of the bias (8a) intervenes in the blocking: while the boss (la) forces the tilting of the ring (8) at point C, the boss (1 lb) is relegated to D in the depression of the

  declivity o its antagonism is inhibited (Fig. 7-B).

  It is difficult to obtain a thread for the (ll) female and (12) male rings whose propeller origin on the generation surface is strictly controlled. In addition the -9 - implantation positions of the bosses (11 a) - (lb) and of the lever (1 5) are subordinate to the pitch of the thread and to the degree of mutual screwing of these rings to obtain the descent of the level of the bosses when the lever (1 5) is moved from point A to point B. It is obviated during development by a complete prior screwing of the ring (l 1) naked on the ring (12) in the presence of the ring (8) in its housing, followed by a partial unscrewing in deduction of the estimated height of the protrusions of the bosses (1a) and (11b) implantable, the pointing of their locations C and D on the collar of the ring (11 ) along the sagittal axis w, v (Fig. 7 -B), then the determination of the lateral pointing concerning the handle (1 5) in position B according to the opening of the notch adopted for the ring (12) holding (for the illustrated example: at the intersection of an arc of 45 with respect to D and an arc of 135 with respect to C); notch which is itself subject to the pitch of the thread used. In this way the relative positions of these elements are theoretically determined to carry out the installation work. By providing a latitude of vertical travel at each of the bosses (l la) and (11b) during their implantation, by a screwed mounting on the collar of the ring (l 1), with maneuvering access on their outer ends, a possibility final height adjustment of the protrusions created is open; it makes it possible to refine the synchronization of the angular displacement of the lever (15) to the common helical positioning of the bosses (11a) and (1b). This adjustment and the fixing of the lever (l 5) are made permanent by the use of a

  blocking means such as a screw brake varnish.

  The freedom of oscillation of the sliding ring (8) causes the piston (3) to deviate in inclination proportional to the distance separating the tilting edge from the notch (5a) of the intermediate jacket in which s clears the claw (3a) for the high position. This distance is related to the stroke of the piston, that is the deployed length of its tube outside the fixed part of the assembly. For a piston with a diameter of 20 mm and for a stroke of 100 mm, a stagnant dead length in the sheath (l) of 40 mm constitutes an admissible value to ensure the telescopic grip in high support. In application of the amplitude of the 0.25 mm tilting of the previous example, the rule of three arithmetic fixes the maximum offset E of the piston (3) at the end of the claw (3a) which can be identified with the thickness of the tube of the intermediate jacket (5): E - 0.25 x 40 / (2012) = 1 mm At the bottom of the sheath (l) the end is closed by the shutter (7) composed of a stopper including an internal friction element (7c), compressed and immobilized between the

- 10 -

  two axially drilled screws and associated locknut (7b), (7d) and (7e), while the end of the spring (2) erected as an appendage (2a) parallel to the longitudinal axis of the assembly, enters a hole or slot (6b) formed in the shutter (7) (fig. 8-r). The headless screw (7b), engaged in the shutter on the inner side of the sheath, designed to be previously maneuvered externally from the bottom of the device by means of a blade screwdriver or preferably a hexagonal wrench (before equipment is completed with the 'shutter (7)), the intermediate protruding part towards the end is partially turned, centers the base of the spring (2) and fixes it against the shutter. This fixing is based on the screwing judged a priori paradoxical of a preferably standardized screw, of slightly larger diameter inside the helix of the spring, whose pitch is different and clearly larger than that of the screw (7b ) finished in prominence P resulting from the shaping of a double flat side in opposition which clears the thread at its top to the underlying level of the intermediate turning. The prominence thus created forms a double index screwable within the turns in the base of the spring. The appendix (2a) of the latter being oriented towards its housing (6b) on the shutter, the spring, by the progression of the screw (7b) in its base, forcing their joint approach, is finally seen to be made integral shutter. The screwing has the secondary effect of tending to copy, at least in part, due to the elasticity of the spring, the value of the pitch of its spiral

  on that of the screw (7b) in this action zone (page 14, line 8).

  The plug (7) is held firmly in the sheath (1) by any suitable means such as a lateral and multiple screwing (7f) in order to protect itself in addition to the permanent forces which this part is founded to bear (reaction of the spring, weight of the user ), also from the persistence of perverse effects arising from vertical accelerations relating to the tremors induced by accidents on the ground. The solution of direct screwing of large diameter of the plug (7) in the base of the sleeve (1) is possible if the preservation of the relative positioning of all the oriented elements of the rod in the common longitudinal plane during assembly of the device is guaranteed (Fig. 8): for flawless operation it is important that the various constituent elements of the rod according to the invention are stabilized in rotation relative to each other in accordance with the representation offered by Figures 1, 2 and 8, in which the bevelling of the ring (8) and of the sleeve (1), the claw (3a) of the piston (3), the notch (5a) of the upper jacket (5) intermediate, and according to the retained solution, the notching or the aliasing of its base and of the corresponding part of the shutter (7) as well as the cell (6a), as well as the erect ends in appendix (2a) of the spring (2) and therefore the receptacle bores (6b) of these ends provided in the shutters, of all die aligned in the sagittal plane of the cycle. To help this end the device includes a

- 11 -

  orientation marking R for installation on the vehicle (Fig. 1): a vertical line of recognition engraved on the outer rear of the sleeve (1) and the piston (3) offers the advantage of having, as position reference, of the existing slot on the frame tube participating in the blocking of the seatposts, system mainly present on existing cycles. When the piston (3) reaches the rest level, its lower end formed by the claw (3a) is housed in the space (6a) reserved in the lower obturator (7). The piston (3) contains in its upper part another shutter (16) essentially consisting of an expandable, elastic sleeve (16d), compressed by screwing. It can be in one piece or fragmented, the depth of the upper shutter (16) in the piston (3) is determined by the desired preload as a function of the spring. The role of the shutter (16) is to immobilize the spring (2) in height and rotation by the lateral pressure it exerts in the prominent part of the piston rod. The association of the top of the spring (2) with the shutter (16) is based on the same principle as for the lower shutter (7); like its counterpart (7b), the upper screw (16b), operable externally from the top of the piston rod by means of a slot with a screwdriver blade or an impression for a hexagonal key, is engaged in the tapped bore a cylindrical body (16a) with base provided with an orifice for containing the upper appendage (2a) of the spring; the upper end of the body (16a) is threaded to receive a specific nut (16c) (Fig. I). Between the nut and the base of the body (16a) resides the element (16d), cylindrical, expandable, of non-slip material, its lateral surface in friction against the interior of the piston swells radially under the effect of axial compression. generated by the operation of the nut (16c), the upper part of which is provided with an actuating means accessible from outside the rod, in the absence of the saddle and its attachment for the occasion. Its adhesion in the enclosure of the piston (3) is multiplied by the significant coefficient of friction of its constituent material if necessary amplified by a chiselled of its contact surface in a series of fine parallel circular grooves. The upper part of the shutter (16) is able to accommodate from the outside a manual tool composed of two elements: a male hexagonal central key holding the body (16a) to prevent it from drifting in rotation when the nut (16c ) is operated in blocking mode and an accessory

  tubular, adapted to it and concentric to the first to operate this maneuver.

  A flexible cable (1 7), passing vertically through the whole assembly comprises a holding intermediate such as a sleeve (1 7a) crimped at its upper end which remains in abutment on the top of the screw (16b). The two screws (7b) and (16b) each carry on the side

- 12 -

  internal of the device a nipple (7a) and (16e) for guiding in soft material to preserve the

  cable (l 7) of erosive friction against them during level changes.

  When deploying the seatpost, the cable (17) internal to the spring stretches between the two shutters (7) and (16). Provided with means (17a) for locking at its upper end and passing through the axis of the shutter (16), it remains fixed between this point and the assembly which forms a clamp (7c) for compression in the lower shutter by the end of which it leaves. The cable is flexible, inextensible and during its installation, pre-twisted to remain constantly confined inside the spring (2); tensioned, the cable determines the total travel of the seat post deployment, validated by a temporary immobilization procedure to adjust its traction relative to the sheath (1). The forceps proceed by compressing a flock obtained in various possible ways, such as the crumpling of a fragment of plastic film mixed with paper or other material such as aluminum foil, landlocked and compacted in the variable volume located in (7c) between the two screws (7b) and (7d) crossed by the cable (1 7). Tightening followed by final blocking of the external screw (7d) induces the concentric grip of the cable by the flock at (7c) and retains the legitimized length. A second sleeve (17b) crimped at the projecting end of the cable

can perpetuate this state.

  The total stroke conceded to the piston (3) corresponds to a value very slightly greater than the top state of the saddle. Under the constant action of the pre-stressed spring (2), a slight automatic inclination of the piston begins and promotes the presentation of its claw (3a) in the notch (5a) of the shirt (5). The user, sitting back down by sliding backwards, causes the tiny descent of the piston which jerks the system. By relieving the saddle of its weight the cyclist allows the spring (2) to expel the emerging claw of the piston (3) out of the notch (5a) at the end of the stroke. This relief, accompanied by an insignificant shift towards the front of the cyclist on the saddle, causes the tilting of the piston (3) automatically re-aligned with the fixed body that constitutes the sheath with the shirt, ready to descend as soon as the user weighs again. To guarantee the correct return of the piston (3), the relevant ends of the latter and of the jacket (5) protrude

  one on the other by a heel and remain coaxial behind the sputtering.

  Two ways of considering the intermediate shirt (5) can be envisaged with regard to its role as a high stop: _ A length setting proportional to the size of the user presumed to be usual; which corresponds to a tailor-made seat post expressly adapted (Fig. 8-m), or, more freely, to its very close size, the approximate choice of the shirt (5) is then

- 13 -

  operated on a batch of elements of predefined lengths likely to encompass the actual format.

  _ A conventional base length based on a minimum size criterion attached to setting the saddle height in the lowest high position for an established cycle model. From this basic element, the possibility of increasing the seat height at will in successive stages up to a maximum capped by the vertical dimensions of the joint parts (sleeve (1) and piston (3)). Which requires maintaining the piston (a) deployed, removing the shutter (7) lower after release of the cable (1 7) and the spring (2) by removing the screw (7d), cleaning of (7c) and loosening of the screw (7b) to allow the introduction of the necessary number of rings (5b) for raising and approaching as close as possible the desired size of the user (Fig. 8-n), adjusted if necessary by resuming the seat adjustment in lower position. It can be carried out by successive gradations over time, defining a wider range of sizes while remaining reversible. Each rework undertaken involves readjusting the length of the cable (1 7) (objectively the cable and the wad will be replaced for this purpose). Constituting the extension of the liner (5), the raising rings are of the same diameter and same thickness as the latter. Their identical height for all is evaluated as a unit dimension. An aliasing of their ends, including that of the foot of the shirt (5), of any shape, guarantees the desired engagement to unify the assembly and oppose any unexpected rotation of the intermediate shirt which has

  an adjustment of its sliding diameter just vis-à-vis the bore of the sleeve (1).

  It follows from this design of the device according to the invention that the saddle is immobilized in the sagittal plane of the cycle in high stability and in low stability. The rigidity in the transient states of descent and ascent of the saddle responding to the only connection by the spring (2) is affected because of its elastic consistency. The resulting fleeting twist ability has no effect on the functioning of the rod, the vertical displacements of the human body not including notable rotary movements during the transitions. However, the use of a spring having a balanced flexibility in compression and a maximum torsional rigidity is strongly recommended. As for applications located outside the cycling sector, in the absence of this solution and by means of a dimensioning of section outside standards for current cycles, the freedom of rotation of the piston (3) in the body (l) can be hampered by l adoption of the very classic concept of splined shaft and hub, or according to a similar concept, of a polygonal section structure causing the entire sliding system to change. If the technology guarantees a solidity compatible with correct operation, a grooving with fine vertical stripes of these elements could maintain the maintenance of the

standardized sizing.

- 14 -

  A particular embodiment of the spring (2), relatively long, offers the advantage of an acceptable flexibility in compression and a consequent rigidity in torsion. For this, the wire of which it is made has a section either elliptical, or rectangular or flat on the order of I × 4 mm, in the perspective circumscribed to a seat post of standard diameter; when the spring is rolled, the wire is arranged so that the small dimension of its section is oriented parallel to its longitudinal axis, with the result that the large orthogonal dimension is maintained in the radial direction. Such a section of the wire

  explains the ease of tracing the spring pitch on that of the screw (7b) (page10 line 18).

  Thus produced, the spring is characterized by torsional rigidity which best limits the phenomenon of twisting which induces a deviation of the saddle from the cycle; he rocks

  its return to neutral position as soon as the cause of the twist disappears.

  The spring (2) declined so far in the description, apart from the particularity of the section of the wire is a conventional compression spring which, like all those of this type, is produced according to a single rolling direction. It turns out that when it is loaded, such a spring twists naturally and in proportion to the crushing undergone, which results in a certain degree of gyration in the opposite direction to the propeller for the end which would remain free during this contraction. It is then necessary to grasp the concept of a spring composed of two equal parts reconstituting the initial length and rolled in opposite directions, having the effect of focusing the rotation of each half spring, conjugated in

  the same direction, on the zone of their meeting in transitory evolutions in the piston (3).

  The gyratory effect dO on compression is thus canceled for the opposite ends of such a

  spring, embedded in their respective shutters (7) and (16).

  If technologically It is not very common, in the current state of the capacities of realization of the compression springs, to obtain specimens comprising in one piece two parts worked in reverse, it remains possible to couple two distinct elements ( 2b) and (2c) by a means capable of maintaining them in compression as in extension. What the sleeve (19) achieves (Fig. 12), resulting from the composition of a first abutment cylinder (19a), hollow, internal to the two springs, with a second shoulder cylinder (19b), discoid and central, pierced and shaped to receive on either side the adjoining appendages of the springs erected as previously mentioned Each of these appendages has a recess whose shape falls in correspondence with that of a circular groove on the shoulder cylinder intended to an elastic ring (l 9c), which locks the connection of the springs when it is put in place. This arrangement is visible in exploded figure 12 which shows the presence of slight external conicities of the cylinder

  abutment to reduce friction against neighboring spring coils.

- 15 -

  The coupling (19) can take other forms such as the following which consists

  to give it the same characteristics as the clamping of the spring on the shutters.

  According to this approach (Fig. 12-A), the coupling amalgamates the shoulder disc (19b) shown in section, with an abutment composed of a hollow stud (19a), comprising at each end threads opposite directions reproducing the screws (7b) and (16b) with their flats in double indexes. To this end the stud (19a) is screwable by the gyratory operation of a tool. Consequently, it becomes independent of the shoulder disc (19b), the object of which consists in its joining with the two spring sections (2b) and (2c), as these are shutters (7) and (16). opposite ends. In this case the recess produced on the appendix provided for the rod (19c) as well as the latter no longer need to exist and each section has identical terminations. To cause the rotation of the stud in one direction or the other results in its

  simultaneous screwing or unscrewing in the two components of the spring (2).

  If a double helical direction spring obtained by reversing the wire drive is easily achievable, the resulting overhang at the reversal point is advantageously bypassed by the insertion of a disc (20 ) cylindrical, interposed, hollow and shaped, replacing the coupling (19) which, like this one, can participate in guiding the spring (2) by means of its appropriate external diameter

  for free circulation in the piston (3) (fig. 12-B).

  In each case relating to the method of obtaining the spring (2), the part wound in reverse of the common sense is dependent on a screw (7b) or (16b) as the case may be, the direction of threading is in correspondence to obtain the desired junction with the shutter (7) or (16) also concerned. The length of the constituent tubes of the device provides for a compression value of the spring (2) thus unified, limited below the crushing point of the turns to touch but also capable of providing an internal volume to the compressed spring in low stability, sufficient to easily contain the

  cable (17) curled up due to its prior twist in mimicry with the spring (2).

  The rotary deviations of the saddle does to the twists present the obstacle of awkward manipulations of the cycle in the stop phase for the stripped version of the seatpost according to the invention, which is compensated by the variant with locking in the high position. In addition, in this last reply, the deviation of the saddle with return to neutral during almost low use finds its justification in the additional possibilities it offers to the movements of the cyclist on his vehicle, by promoting the pivoting of the head. and the trunk stopped or in circulation, the movement accompanied by the saddle in

  increases the scope and certainly the safety by widening the rear vision.

- 16 -

  An approach which resolutely deviates from the preceding considerations makes it possible to envisage a tube contour capable of longitudinal guidance, more satisfactory on the

  plan of the consumption of radial space than that which relates to the traditional grooves.

  As an example, the use of a circular section of the three concentric elements (1), (5), and (3) deformed by a reprofiling leading to a local indentation distributed over each of the cylindrical envelopes according to the length of the generator (Fig. 13 - section C). The spring (2) can also benefit from a similar shaping even when approached and

  finds the classic design in circular section wire with the ends made free.

  The top and bottom shutters also evolve towards adaptation to the profile (Fig. 13); they are released from the constraint to counter tubular rotation, while the screws (7b) - (16b) as well as the need for aliasing or notching of the jacket (5) and its enhancements (Sb) are eliminated. Similarly, the sputtering between the piston (3) and the jacket (5) no longer needs to be in the sense of anti-gyratory locking, the connection only exists under the re-entrant stop and a simple release cut indifferently on the top front of the shirt or on the foot of the piston according to a large half of a portion of cylinder creates in each case a rear heel to contain an axial projection of the withdrawal of the piston relative to the sheath in a phase back to the lowered position. The tilting ring (8)

  and its embolism (11) - (2) reported are not affected.

  Taking advantage of the possibilities introduced by the tubular profiling expressed in FIG. 13 for vertical guidance, a more sophisticated processing optic brings an additional technical simplification by abandoning the ancillary elements. It is doubled by a relative industrial complication linked to the treatment of more demanding forms in machining and shaping and leads to the option presented by Figure 14. The annexes that constitute the cable (1 7) and its immobilization structures disappear of this 2 context; thus the device is ideally reduced to its basic components; _ Figure 14 (low position), in which the upper ejection stop is a thin shoulder (3b), formed on the piston (3), stopped by an inner lip (t1 b) formed at the top of the sheath (1) , shows the preserved elements which revolve around the pipes (1), (3), and (5) and which boil down to the expansible shutter (16), the shutter (7) cap, the rings (Sb) of raising and embolture (11) - (12) complete with the tilting ring (8). _ The lightened figures 14-A and B represent the deployment in the high position followed by the tilting of the seatpost, based on a height adjustment surrounding a minimized size of the user and in which the additional rings (Sb) are distributed, for one to raise the shirt (5) and three others to compensate

  high stop, in order to compensate for the absence of the restraint constituted by the cable (l 7).

- 17 -

  _ The light figures 14-C and D apply to the deployment and tilting of the rod reaching the maximum possible height of the adjustment, relative to a major size

  cyclist, in which the rings (5b) all participate in raising the saddle.

  Another step is taken by developing a solution which combines the profiling mentioned in Figure 13 and the upper stop of Figure 14 with the integration of the jacket (5) in the sleeve (1) closed by the shutter (7) lower whose front has a relief suitable for the seat of the spring and the lowered piston. In this perspective the shirt (5) is materialized by a shoulder (5c) internal to the sheath (1) located at the level corresponding to the low waist estimated for a basic format, starting point for the height of the saddle adapted to the size of the cyclist. The outcome of this degree of elaboration seems to be subordinated to a precision molding process, sparking, or even to a relevant production approach by its novelty, chosen in timely convergence with

  assimilation of the complex shape of the embolism (1) - (12) of the ring (8) (fig. 15).

  The device benefits from the concept in combination with the personalized adjustment through the use of cylindrical raising rings (5b), made of a material capable of granting them a substantial radial flexibility combined with a predominant axial rigidity. Subjected to elastic deformation under the action of lateral pressure, they are of a diameter calculated to make it possible to insert them into the sheath (1) in order to bear on the shoulder reproducing the jacket (5) when crossing the neck caused by the lip (1 lb) when they are put in place; or again, always cylindrical and elastic, they become laterally deformable by

  the existence of a slot of suitable width which opens them along their height (Fig. 1 3 -

  section B). The rings are prepared to provide a gripping means such as edge chamfering in order to facilitate their possible extraction with a tool exploiting the

  lateral flexibility of the rings, capable of insertion between the wall of the body (1) and these.

  This solution widens towards the case of the fixed body which proceeds from the shaping of revolution (Fig. 1) in which the replacement of rigid pipes (5) and (5b) by generalization is widespread.

  elastically deformable cylindrical elements.

  A stop ring (3c), formed in the profile of Figure 13 (section B or C), is interposed between the piston (3) and the inside of the sleeve (1). The degree of tightening of its insertion keeps it at the upper level in contact with the upper compensation ring (5b) or the lip (1b) of the sleeve (1) at the maximum adjustment, in the tubular space existing between this high point and the shoulder (3b) of the piston. In the absence of tension of the cable (17) the rod (3c) -18 - limits the ascent of the piston (S), its role consists in consolidating the upper stop (1b) that the

  necessary operating games could allow to overflow.

  The mobility of the body, required for operations to change the level of the saddle, is naturally assimilated to pedaling and does not require any prior learning. The choice of the constituent materials, their processing and implementation are devolved to those skilled in the art to result in the development of a durably reliable product, faultless in its operation. Used individually, the device for the invention is particularly designed for cycles. It extends to the domain of sigw and assimilated, most often on the basis of two or more parametric units acting in step, when two levels of plane are sought alternately & otammen a work post can receive these two niwveaur commonly activated as for a dominated table, the solution encountered is a succession of postures asise and standing The possibilities of applications are spreading beyond the few following examples which relate to silent siesW partcip4nt for one to the arrangement of modular devices help with the evolution of people with motor disabilities, - for another and in A & same spirit that can be part of the function of physiotherapy rehabilitation complexes or bodybuilding equipment. This type of seat can still meet the equipment of the cockpits of certain specific vehicles requiring on the same space, a place of conduct for moving walls accompanied by a

  vertically offset position, suitable for the building actviM.

  Outside the field of saddlery, the particularities of the bistable structure according to the invention make it possible to envisage the collective inclusion of copies in

  parallel or independent or even antagonistic operation, on specialized machines and robots25, with the aim of assigning them additional functions.

-19-

Claims (8)

  1) Telescopic bistable structure composed of a hollow and blind piston sliding in a blind sleeve, comprising an elastic compression element interposed between these two blind parts as well as an intermediate jacket conforming to the inside of the sleeve, in immobility between it ci and the piston and offering to the latter a translation in any spatial orientation under the double action of opposing alternating forces, to accomplish sliding sliding phases between two distinct states of stability, characterized in that: - the length of the intermediate jacket determines the piston stroke; in that: _ the free end of the jacket represents the end of the piston output stroke controlled by the action of a lateral impulse impulse force external to the device; in that: _ a rocking ring contributing to the sliding of the piston ensures the transmission of the deviating force; and in that:   _ the piston is made blind by a movable shutter adjustable in position.   2) Bistable seat post composed of a hollow piston and blind cap sliding in a blind sleeve (1), comprising an elastic element (2) of compression interposed between these two blind parts as well as a shirt (5) intermediate marrying the inside of the sheath (l) in immobility between the latter and the piston (3) and offering the latter a translation in vertical or even oblique orientation under the double action of alternating forces, one of which, rising, is developed by the elastic element (2) in compression, and ensures two levels of attitude superimposed on any device belonging to the field relating to seats and assimilated as a cycle saddle for which the rod is integrated into the frame by supporting the saddle with the load which it undergoes sporadically, characterized in that: _ the length of the intermediate jacket (5) determines the stroke of the piston (3) measured from the free end of the jacket (5) to a shutter (7) fixed terminal at the opposite end which blinds the sheath (1), constitutes a retaining stop for the liner (5) and the elastic element (2), and acts as a limit stop for the piston ( 3) retracted; - 20 -   in that: _ the free end of the jacket <(5) represents the end of stroke of the piston (3) in the extended position, its appearance is complementary to the end of the piston (3) trapped in the sheath (1) which is arranged to allow their mutual and stable meshing under the effect of an external lateral impulse deflecting the piston (3) against the internal wall of the sleeve (1); in connection, a complementary reproduction of the gear on the shutter (7), identical in principle, becomes operational when the piston <3) is fully retracted; in that: - the piston (3) is blinded due to the presence in its internal terminal part of a shutter (16) adjustable in position in a mobility that allows its deficit diametrical dimension compared to the caliber of the rod piston (3); the shutter (16) is kept locked in position following the volumetric expansion of its constituent cylinder caused during its axial compression obtained by suitable and common means such as screwing; and in that: _ a ring (8), self-lubricated contributes to the sliding of the piston (3) and remains in contact with the end of the sleeve (1) by their common faces, which each have a bevel according to two angularly differentiated symmetrical declivities of a minimal value leaving to the sliding ring (8) a tiltability on the confused edges, perpendicular to the plane of symmetry with respect to the point of application of the control pulse if the principle chosen is based on subtraction a low angle value applied to one or the other of the paired bevels, or a partial rolling ability on the end blanks of the sheath (1) parallel to the plane of symmetry, if the choice stops at l addition of a similar angle value applied to the same system bevels.   3) Bistable seat post according to claim 2, characterized in that: _ the sliding ring (8) imperfectly matching the corresponding declining surfaces of the sheath (1) retains a freedom of alternating tilting in the plane of symmetry coincident with the sagittal plane of the cycle while remaining packaged in a socket formed by a nut intended for a ring (1I) female, partially screwed onto a ring (12) male, holding, connected to the sheath (1) by means of attachment; and in that: _ the retaining ring (1 2) is an integral part of the sleeve (1) as a part - 21 -   of pure revolution complete with an additional support ring (beveled separately),   reported, in accordance oriented and definitively secured by a connecting means.   4) Bistable seat post according to claim 2, characterized in that: _ the sliding ring (8) imperfectly matching the corresponding declining surfaces of the sheath (1) retains a freedom of alternating tilting in the plane of symmetry merged with the sagittal plane of the cycle while remaining conditioned in a socket formed by a nut intended for a ring (11) female, partially screwed onto a ring (12) male, holding, connected to the sheath (1) by means of attachment; and in that: _ the retaining ring (12) is an integral part of the sleeve (1) as a part of revolution completed by a beveling in accordance with the orientation when it is machined in its mass.   ) Bistable seat post according to claim 2, characterized in that: _ an adhesive bandage (18), flexible and self-sealing, constrains the tilting ring (8)   at the beveled top in accordance with the orientation of the sheath (1).   6) Bistable seatpost according to claims 3 or 4, characterized in that:   _ the ring (l1) nut has a boss (11a) on the internal shoulder of its collar, pointed along the line of the bevelled edges x, y in bistable phase A, maintained in contact with the upper face of the ring (8 ) sliding and tilting along a partial rotation of the ring (11) nut which acts as a helical operating member for a temporary blocking of the saddle at the high level by immobilization of the ring (8) in tilted position; in that: _ a second boss (1l 1b) implantation symmetrical to the first on the line of the edges x, y, assigned with it to the maintenance of the ring (8) while allowing its oscillation in bistable phase, loses all potential during blocking B, being exported by the rotation of the ring (11) nut above a zone (8a) of the upper half-face of the ring (8) oriented towards the sagittal front along the axis of symmetry w, v, of neutralizing effect 30 by its declining shape like the oblique of the lower slope (8b), in that: _ a lever (15) whose screwable end is fixed blocked through of the ring (11) nut, evolves in a notched space (1 2a), practiced on a fraction - 22 -   circular of the upper threaded part of the retaining ring (12), of a width adapted to the extent of the mobility defined for the bosses (11 a) and (11 b) in equal distribution along the axis w, v ; The notch (12a) allows and delimits the maneuver, balanced with respect to the sagittal plane, of the ring (l 11) nut, which stabilizes on the extreme positions of the handle (15) which incorporates with the ring (8) a ball anchoring system or other means, hardening each of the two stationary states A and B of the ring (l 1) nut; and in that: _ the bosses (11a) and (11b) are each provided with means for adjusting the height of their prominence relative to the shoulder of the collar of the ring (11) nut which carries them, for example of screwing type blocked in their implantation, accessible from the outside, in relation to the final synchronization of the movement of the lever (15) leading to the helical positioning of the bosses (11 a) and (l1 b) on the milestones C and D   which are respectively assigned to them on the top of the tilting ring (8).   7) Bistable seatpost according to claims 5 or 6, characterized in that:   _ the length of the intermediate jacket (5) which materializes the stroke of the piston (3) is designed in a single piece and corresponds to a size close to that of the privileged user of the cycle, by an approximate choice made on a batch predefined sections   likely to include its actual size.   8) Bistable seatpost according to claims 5 or 6, characterized in that:   - the length of the shirt (5) establishes a reference height which reflects the size of a user of moderate size, which can be raised as required by a set of rings (5b) of the same kind, representing a unit fraction of the length basic; the rings fit into each other as well as into the terminal shutter (7) by a crenellated structure of their ends preferred to a combination   possible notches, maintaining the entire extension.   9) Bistable seatpost according to claims 7 or 8, for which one uses   cylindrical tubes to constitute the fundamental body formed by the sleeve (1), the jacket (5) and the piston (3), characterized in that: _ the elastic element (2) is in the form of a spring of compression of which the cross-section of the constituent wire comprises two orthogonal axes of distinctly differentiated lengths such as those of the ellipse, of the rectangle or of the flat and whose helical rolling is carried out in orientation of the small dimension of the cross-section of the wire along a parallel to the longitudinal axis of the spring; - 23 -   in that: this spring comes from two equal helices in dimensions and qualities, rolled in opposite directions reconstructing its appropriate length in the arrangement of the structure; in that: _ the double helix of the spring (2) implies that the part wound, unlike the common sense, receives a screw with a thread adapted to this direction to make the junction with the shutter also concerned; in that: _ the intermediate jacket (5) and the lower end of the spring (2) are kept fixed in rotation and translation in the shutter (7) of the sleeve (1), by means of either notches or a circular aliasing for the intermediate jacket (5) and an orifice arranged to receive the end of the spring (2) erected as an appendage (2a) oriented along its longitudinal axis; in that: _ the shutter (7) of the sheath (11) incorporates a gripper (7c) transverse, of compression, with a concentric locking action by compacting the flock of a crumplable body, under the effect of the screw ( 7d) axial, projecting externally to the device, tightened in the direction of a grub screw, projecting internally in the structure; and in that: _ the headless screw (7b) whose protruding outgoing end of a turning, shaped into a double index, operable using a conventional means such as an impression for a hexagonal key from the outside and through the compression clamp (7c), is screwed into the internal spiral at the base of the spring (2) and associates it with the shutter (7). 10) Bistable seat post according to claim 9, characterized in that: the upper shutter (16) is intended to ensure the prestressing adjustment of the compression spring (2) and the locking in rotation and translation of its upper end. itself shaped for this purpose in appendix (2a) which engages in a suitable orifice of the shutter (16) such as a slot, against which it is held by a screw (16b) similarly paired with that (7b ) of its lower part, and crossed by a cable (l 7) immobilized at the top end of this screw (16b) by a means such as a matted sleeve; and in that: _ the total deployment of the spring (2) and with it the complete stroke of the piston (3) are limited by the maximum tension of the flexible cable (17), internal to the spring (2), pre-twisted during assembly,   subject to its holding elements: the compression clamp (7c) which it passes through in the sheath (1) and the shutter (16) which fixes it in the piston (3).   24- 11) Bistable seatpost composed of a hollow and blind piston (3) sliding in a blind sleeve (1) and comprising an elastic element (2) of compression interposed between these two blind parts, characterized in that: a cylindrical clearance made on the inner wall of the sleeve (1) extending towards its top determines the stroke of the piston (3) measured from the origin of the clearance up to a fixed shutter (7) at the opposite end which makes blinds the sheath (1), constitutes a holding stop for the elastic element (2) and plays the role of an end of stroke stop for the retracted piston (3); in that: _ the origin of the clearance made in the sheath (1) constitutes a shoulder which represents the end of the exit stroke of the piston (3) in abutment on this shoulder by the end of its foot (3a); in that: _ the end of the foot (3a) of the piston (3) is shaped at an appropriate angle to provide a maximum contact surface against the shoulder of the sleeve (l) on the front part in combination with a longitudinal extension at the heel of the piston (3) on the rear of the sleeve (1) sufficient to prevent any overlap during the withdrawal phase; in that: _ the sliding sleeve (1) and piston (3) assembly has a pseudo-circular section which defines a profile radially retracted over a localized area of the contour, of cardioid appearance, offering the piston (3) a guaranteed translation strictly linear guidance; in that: _ the sheath (1) has a shoulder (l b) narrowing the inner periphery of the orifice at the top end of the sheath; in that: _ an external shoulder (3b) limits the length of a diametrical narrowing of the upper part of the piston <3) in mobility through the top orifice of the sheath (1); in that: _ an open and flexible rod (3c), of any cross-section, is interposed between the shoulders (lb) and (3b) by means of one or more raising rings (5b), at the end piston exit stroke (3); in that: _ the top end of the sheath (l) incorporates the retaining ring (12); and in that: _ the raising rings (5b) take on the appearance of open hollow cylinders and   have axial rigidity and radial flexibility.