When riding a two-wheeled bicycle it is the most comfortable for the bicyclist if he has a possibility to extend his legs. In such a situation the cycling is not tiring for the bicyclist and k is possibie to provide for a maxima ! use of leg muscie power to drive the bicycie.

It necessitates to fix the bicycle saddle at a suitable height in such a manner that the bicyclist can extend his legs when the pedals during the rotation are situated at their lowest reverse position, i. e. in most cases ten or so centimetres above the ground on which the bicycle moves. The bicycle saddle can be vertically adjusted, individually for every bicyclist, but such along adjustment is fixed and invariable during the bicycle ride.

Due to such a construction of the bicycle, especjally during cycling in municipal traffic, when there is a necessity to stop abruptly and frequently in front of the traffic lights or other obstacles, the bicyclist must descend the saddle or incline sideways during bike stops or standstills. Furthermore, the bike start is also more difficult, since the bicyclist must maintain equilibrium at a moment just before getting on the saddle. It creates a risk of accident in tight and overcrowded municipal traffic and causes inconvenience for the bicyclist. Therefore in order to maitain equilibrium, especially in the case of the elderly, it is required to make use of three-wheeled bicycle which prevents against the loss of equilibrium and ensures a reliable cycling.

From the Polish patent specification No. 163300 a stabilizing system for the one-track vehicle, mainly bicycle, providing for the maintenance of the bicyclist's equilibrium during stops, is already known. The stabilizing system has the support mating with the stabilizing wheels located at both sides of the bicycle. The support is lowered to the ground on which the the bicycle moves along and it lifts the rear bicycle wheel. However, such a constructional solution is an unpractical one and requires a wide tread of the stabilizing wheels to ensure an effective support of the bicycle.

Known are also constructions of bicycles, for instance, from the Polish Patent Specifications No. 141889 and No. 172053, in which the bicycle saddle alternatively together with the pedals constitutes a driving gear owing to the changes of positioning from the upper position to the lower one and vice versa.. When the bicycle saddle is in the lower position, i. e. in the lowered position, the bicyclist can effectively and reliably stop in front of the obstacle while maintaining equilibrium. In most cases it is impossible, since the bicycle saddle comes to rest during the cycling in a position other than the lower position.

Known is from the Polish patent specification No. P-304912 the bicycle support located under the saddle, providing for shock absorbing connection between the saddle and the bicycle frame. The bicycle support consists of two coaxial tubes, whereby to the one under the saddle, the bicycle saddle is fixed while in the frame tube the shock absorbing pad is inserted into the element of the bicycle main frame.

Known are also shock absorbing brackets to fix the bicycle saddle, for instance, from the Polish applications of utility models No. W-103972 and W-103273. The shock absorbing brackets have a guide tube and an elastic element in the form of a spring, located inside. The spring is furnished with a guide screw whose the upper end protrudes outside and has a fixing sleeve. Under the bottom a threaded stopper is foreseen.

Both the support under under the bicycle saddle and the shock absorbing brackets lead to the suppression of shocks caused by riding on the uneven ground. Due to the mounted elastic element the bicycle saddle changes its vertical position during the ride, but only within specified and admissible limits of the parameters caused by the byciclist's weight.

Such a constructional solution is an ineffective one for ensuring the maintenance of bicyclist's equilibrium during stops and standstills, since the mounted elastic element does not bring about a required vertical change of the saddle height under the action of the bicyclist's weight.

The objective in this invention is to improve the one-track vehicle, especially a two-wheeled bicycle and to eliminate all the above mentioned inconveniences and limitations. This mention enables the bicyclist to stop and stand without a necessity of getting off the saddle. It is also purposeful to develop such a type of fixing the saddle to the bicycle which could be installed as an exchangeable bicycle component part without a necessity to alter the bicycle main construction.

This objective could be achieved thanks to the construction of the bicycle saddle set with a variable vertical position.

According to the invention, the bicycle saddle changes its height in a stabilized and controlled manner from the raised position to the lowered position before or during the bicycle stops and from the lowered position to the raised position before or during cycling start. A difference between the heights of both saddle positions is at least equal or greater than that between the distances of the lowered legs of the bicyclist's sitting on the saddle set up in the raised position, measured from the ground on which the bicycle moves along. The saddle is furnished with the position interlocking in the raised position. A position of the saddle can be changed at a given height from the rised position down to the lowered position due to a variable vertical fixation by means of the support mounted under the bicycle saddle secured to the main bicycle frame.

The bicycle saddle has been provided with the position interlocking in the upper position, which can be released by a hand lever and is interconnected with the hand lever through a tension member. The said hand lever is located on the bicycle handle-bars.

According to the invention, the position interlocking can be released by means of a tension member and force exerted by leg muscles during the backward motion of the pedals.

When a vertical position of the saddle is changed from the raised position to the lowered position, the position interlocking is advantageously situated in the lowered position.

The saddle position is changed from the raised position down to the lowered position under the action of the bicyclist's weight once the saddle has been unlocked. The saddle position from the lowered position up to the raised position is changed under the action of the elastic element compressed during the change of the saddle position from the raised position down to the lowered one.

It is advantageous when the saddle movement to the lowered position and/or up to the raised position is dampened by means of a damper which controls speed and gentle continuous positioning. The damper should be preferably set working at the final stage of reaching the upper and lower position.

The raised position of the bicycle saddle is interlocked by a toggle mechanism. The toggle mechanism should preferably have a cage-type construction and be outfitted with three (3) pivot axles, whereby at least two (2) pivot axles have only a single degree of freedom. about its own axle. The bicycle saddle set equipped with the saddle set bracket, the tube of the saddle and the saddle, according to the invention, characteristic in that the saddle set bracket and the tube of the saddle are mutually interconnected by means of a toggle mechanism outfitted with an elastic straightening element mounted at least on one of the pivots.

According to the invention, it is advantageous that there is an additional elastic element located inside the saddle set bracket, preferably in the form of a spring. Such additional elastic element should be mounted on a pilot bar.

The saddle set bracket preferably has been provided with packings. It is purposeful that the elastic straightening element is mounted on the middle axle of the toggle mechanism and is preferably in the form of a torsion spring.

According to the invention, an elastic coupling has been preferably mounted on the middle axle.

The invention enables the bicyclist to maintain equilibrium in his position without a necessity to descend the bicycle saddle during bicycle stops, standstills and starts.

The advantage of the invention is the fact that it facilitates the start and stabilizes the cycling when. the-bicycle starts moving and stops. The bicyclist can fully control his bicycle and therefore increases both safety of cycling and safety of other road users.

The constructed bicycle saddle set can be intended for the application in various types of bicycles, since it may be exchangeable with the typical bicycle component part and can be separately mounted by every bicyclist who already owns a bicycle, without a necessity of assistance from specialistic service workshop.

The objective of the invention will be described in more detail below with the aid of an embodiment represented in the drawing which Fig. 1 shows a side of a two-wheeled bicycle outfitted with the bicycle saddle set, designed according to the invention, in the cross-section and with a broken line in the raised upright and lowered position, respectively, and Fig. 2 shows a view with a part section of the bicycle saddle set in the raised position, and upright Fig. 3 shows a view with a part section of the bicycle saddle set in the lowered position.

According to the invention, a height of the saddle 4 can be changed from the raised position 6 down to the lowered position 7 by means of the toggle mechanism 10, the upper arm I Oa of the said toggle mechanism 10 is fixed to the tube 8 of the saddle in the point 14 while the lower arm lOb ofthe said toggle mechanism 10 is attached to the bracket 9 in the point 15.

The toggle mechanism 10'from the raised upright position is ejected by an-ejector 10 pivoted on the lower axle 20. The tube 8 of the saddle is coaxially and displacable mounted in the bracket 9 of the bicycle saddle set 3, adapted-in tum-to the installation in the tube 2 of the main frame 1 and fixed by the clamp 5 of the bracket. The position of the saddle 4 can be changed under action of the weight of the bicyclist who sits on the saddle once the toggle mechanism 10 has been unlocked. The said toggle mechanism 10 provides for interlocking the saddle 4 in the raised position 6 during the cycling. The said toggle mechanism 10 has a cage-type construction. It can be unlocked by means of the hand lever 29 located on the handle-bars 33 which is interconnected with the said toggle mechanism 10 with the help of the elastic tension member 6. The changed position of the saddle 4 from the raised position 6 down to the powered position 7 leads to the compression of the spring 21. It takes place at a moment just before or du-mythe bicycle stop The bicvclist can then freelv extend his legs and remove them from the pedals 30, touching with his feet the ground on which the bicycle moves along and maintaining equilibrium during standstills. Thanks to the application of the spring 21 it is possible to ensure the controlled lowering of the saddle 4 and partially absorb the travel caused by the displacement of the saddle downward.

Energy accumulated in in the spring 21 under the action of the bycyclist's weight permit to shift the saddle 4 back to the raised position 6 before and during starts or during the cycling. For this purpose the bicyclist must raise himself a little up when pressing with his legs on the pedals 30.

A difference between the height of the saddle 4 situated in the raised position 6 and in the lowered position 7 is at least equal or greater than that between the distances of the lowered legs of the bicyclist sitting on the saddle 4 set up in the raised position 6, measured from the ground on which the bicycle moves along.

It is of avantage when the saddle 4 has the position interlocking in the lowered position 7 <BR> <BR> <BR> (Fig. 3), where the catch pawl 13 of the ejector 11 rests on the projection 17 on the upper<BR> <BR> <BR> <BR> <BR> <BR> arm 1 Oa of the toggle mechanism 10. From practical reasons it is advantageous when the ejector 11 and the catch pawl 13 of the interlocking constitute a single compact element.

In order to increase and improve shock absorption during the lowering of the saddle 4, from the raised position 6, the fluid dash-pot 39 regulating a speed. and continuous movement. of the saddle 4 should be foreseen.

The toggle mechanism 10 is outfitted with three pivots: the upper axle 18, the middle axle 19 and the lower axle 20 have only one degree of freedom around their own axle.

The application of the invention provides for a safe cycling, especially in-municipal traffic during bike stops, standstills and starts, enabling the bicyclist at the same time to maintain equilibrium and a full control over his bicycle, owing to the support on the ground with his legs, without a necessity to descend the saddle 4.

The bicycle saddle set 3, as it has been shown in Fig. 2 and Fig. 3. ; ils outfitted with the additional torsion spring 22, initially stressed, the end 25 of which rests-in the raised position 6 of the saddle 4-on the stop projection 34 of the upper arm I Oa in the toggle mechanism 10. The spring 22 in Fig. 3 has been shown in the position of additional stressing, whereby the end 25 of the said spring rests on the projection 26 on the tube 8 of the saddle, intensifying the action of the spring 21. The spring 22 should be preferably stronger than the spring 21. The bicycle saddle set 3 incorporates the shock absorber 38 which provides for damping at the final stage of movement of the saddle 4 from the lower position 7 up to the upper position 6. The shock absorber 38, as it has been shown in Fig. 2 and Fig. 3, is mounted between the projection 37 of the bracket 9 and the ejector 11. The shock absorber 38 should be preferably of fluid dash-pot type 39. Furthermore, it is advantageous that the tube 8 of the saddle contains the spring 23 mounted on the pilot bar 24, designed for intensyfying the action of the spring 21 in such a case when the toggle mechanism 10 has not beenequipped with the accesory spring 22. In order to guarantee an optional operation the bracket 9 is preferably filled inside with a certain amount of lubricating oil 36.

Alternatively to the above-described method, the saddle 4 may be lowered from the position 6 down to the position 7 through the rotations of the pedals 30 backwards.

To achieve this goal the ejector 11 is connected via the tension member 27 with the rotary element 31 mounted on the driving axle 28, whereby the set driving axle 28 is interconnected with the pedals 30.

SPECIFICATION OF REFERENCE SIGNS 1. MAIN FRAME 2. TUBE OF THE MAIN FRAME 3. SADDLE SET 4. SADDLE 5. CLAMP OF THE BRACKET 6. RAISED POSITION OF THE SADDLE 7. LOWERED POSITION OF THE SADDLE 8. TUBE OF THE SADDLE 9. BRACKET 10. TOGGLE MECHANISM 10a UPPER ARM OF THE TOGGLE MECHANISM 1 Ob LOWER ARM OF THE TOGGLE MECHANISM 11. EJECTOR 12. ARM OF THE EJECTOR 13. CATCH PAWL OF THE INTERLOCKING FIXATION TO THE TUBE 14. POINT FIXATION TO THE TUBE OF THE SADDLE 15. POINT FOR THE FIXATION ON THE BRACKET 16. TENSION MEMBER OF THE EJECTOR 17. PROJECTION ON THE TOGGLE MECHANISM 18. UPPER AXLE 19. MIDDLE AXLE 20. LOWER AXLE 21. SPRING 22. ACCESSORY SPRING 23. SPRING IN THE SADDLE TUBE 24. PILOT BAR 25. END OF THE ACCESSORY SPRING 26. PROJECTION ON THE SADDLE TUBE 27. TENSION MEMBER 28. DRIVING AXLE 29. HAND LEVER 30. PEDALS 31. ROTARY ELEMENT 32. STOPS 33. HANDLE-BARS 34. STOP PROJECTION 35. ADJUSTING SCREW 36. LUBRICATING OIL 37. PROJECTION OF THE BRACKET IN THE SADDLE SET 38. SHOCK ABSORBER 39. FLUID DASH-POT