Abstract:
A seat for a two-wheeled vehicle comprising a relatively soft saddle support for a rider where the saddle support has a longitudinal direction axis and a cross direction axis as well as a supporting structure connecting the saddle support to a seat-carrying upright of the vehicle. A longitudinal oscillatable pin is provided between the upright and the supporting structure, where the oscillatable pin has a longitudinally extends substantially along a full extension of the longitudinal axis of the saddle support to allow the saddle support to oscillate about said longitudinal axis of said saddle support. A means is provided for preventing the oscillatable pin from oscillating and thereby preventing the oscillation of the saddle support.

Description:
FIELD OF THE INVENTION 
   The present invention relates to a seat for two-wheeled vehicles, bicycles, motorcycles and scooters for example, capable of oscillating around its longitudinal axis. 
   BACKGROUND OF THE INVENTION 
   It is well known that when a cyclist pushes on the pedal, the upper internal part of his thigh rubs against the parts of the seat with which it is in contact and that this causes rubefaction and discomfort. Furthermore, the seat&#39;s rigid response to the movements carried out during the pedaling contributes in a not negligible manner to the feeling of discomfort typically associated with remaining for a long time on the seat of a bicycle and, after all, to the strain felt by the cyclist. 
   The document EP 0091016 discloses a part for a bicycle according to the preamble of claim  1 . 
   OBJECT AND SUMMARY OF THE INVENTION 
   The general purpose of the present invention is to provide a seat for two-wheeled vehicles that will make it possible to avoid the drawbacks that have just been outlined. 
   A particular aim of the present invention is to provide a seat of the aforementioned type that will be capable of oscillating about its longitudinal axis and such that said oscillation can be locked. 
   Another aim of the present invention is to provide a seat of the aforementioned type in which the amplitude of the oscillation about its longitudinal axis can be adjusted. 
   A further aim of the present invention is to provide a seat of the aforementioned type in which the oscillation is associated with the possibility of the seat sliding in the longitudinal direction in such a way as to permit the seat configuration to be adapted in an optimal manner to the road on which the cyclist is moving. 
   These aims are attained by the seat in accordance with the invention of which the essential features are specified in claim  1 . Further important characteristics are set out in the dependent claims. 
   The salient feature of the seat for two-wheeled vehicles in accordance with the present invention consists in that it is mounted on a pin capable of oscillating around its longitudinal axis and that there are provided means capable of both locking the oscillations and regulating their amplitude. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other features and advantages of the seat for two-wheeled vehicles in accordance with the present invention will be brought out more clearly by the following description of some embodiments thereof, which is given by way of example and is not to be considered limitative in any way, the description making reference to the attached drawings, of which: 
       FIG. 1  is a bottom plan view of the two-wheeled vehicle seat in accordance with the invention; 
       FIG. 2  is a longitudinal section through the seat along lines II-II of  FIG. 1 ; 
       FIG. 3  is an enlarged view of the detail surrounded by a circle in  FIG. 2 ; 
       FIG. 4  is a schematic longitudinal section through a variation of the seat of  FIGS. 1-3 ; 
       FIG. 5  is a schematic longitudinal view of a second embodiment of the seat in accordance with the invention; 
       FIG. 6  is a schematic side elevation of a third embodiment of the seat in accordance with the invention; 
       FIG. 7  is a schematic side elevation of a fourth embodiment of the seat in accordance with the invention; 
       FIG. 8  is a simplified variation of the seat in accordance with the invention; 
       FIG. 9  is a fifth embodiment of the seat in accordance with the invention; 
       FIGS. 10 ,  11  and  12  illustrate other possible solutions for the mans of regulating the amplitude of the oscillation of the seat. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to  FIGS. 1-3 , the reference number  1  has been used to indicate a support that bears the rider and constitutes the upper part of the bicycle seat, or saddle pad, made of a yielding and soft material (leather, plastic or similar) and is provided with a lower part constituting the supporting structure made up of the crosspieces  2  and  3 , indicated respectively as the forward and the rearward crosspiece, which are made of rigid material and are connected to each other by the round bars  4  and  5 . 
   In the forward crosspiece  2  there is housed a first bushing or bearing  6 , while a second bushing or bearing  7  is applied to the rearward crosspiece  3  by means of a strip  8  fixed to the crosspiece  3  by means of screws  9 . The two ends of a pin  10  that extends longitudinally and is rigidly connected to the upright  11  carrying the saddle are rotatably housed in the two supports  5  and  7 . 
   Pin  10  is provided with a stiffening plate  12  that facilitates the longitudinal sliding and enhances the flexural rigidity of the pin. Pin  10  also has a first shoulder  13  that acts as a stop for the first support  6  and, at the opposite end, a second shoulder  12  that acts as a stop for the second support  7 . As can better be seen in  FIG. 3 , second shoulder  14  is of a substantially discoidal shape with a radial notch  14   a . A ratchet  15  is attached to the crosspiece  13  by means of a strip  16  and screws  17  and can slide across it in a position corresponding to notch  14   a  of shoulder  14 . Ratchet  15  is provided with a small lever  18  to permit its being easily gripped and made to slide across the crosspiece  3 . When it is desired to lock the oscillation of the saddle  1 , ratchet  15  has to be slid until it engages with notch  14   a . When the ratchet is not engaged with notch  14   a , the saddle can oscillate freely. Two end-of-run stops, indicated by  19  and  20 , are provided on the ratchet and correspond, respectively, to the positions in which the ratchet is disengaged from notch  14   a  and engaged with it. 
   The position of saddle  1  with respect to upright  11  can be regulated by causing pin  10  to slide with respect to head  21  of upright  11  after having slackened locking screw  22 . 
   Alternatively, the supports  6  and  7  can be provided with rubber articulations of a known type to perform the same function. 
   In the variation of  FIG. 4 , where components equal to those of the previous figures are always indicated by the same reference number, round bars  15  (one only can be seen in  FIG. 4 , the other or the others being hidden by it), which form part of the supporting structure of saddle  1  and are rigidly locked to the head of saddle-carrying upright  11  by means of the tightening of screw  22 , converge onto two pins  23  and  24  that are rotatably engaged in small blocks  2  and  3  of saddle  1 , where the blocks may or may not be provided with a rolling support. A device, generically indicated by  26 , is also provided for locking seat  1  with respect to pins  23  and  24 , and may be, for example, of the type illustrated in  FIGS. 1-3  or some equivalent device. 
   In order to limit the torsion between the front and the rear part of saddle  1 , one or more metal ribs, indicated by the reference number  27 , made of metal or some other torsion-resisting material, may advantageously be inserted in it. 
   The supporting structure, indicated by  25  in  FIG. 4 , may also be made of just one appropriately sized round bar or other metallic rod of which the ends act as trunnions. The size of the trunnions is such that they can safely be inserted in seatings  2  and  3  without there being any risk of their slipping out and to this end they may also be provided with appropriate locking systems of a conventional type. 
   Another embodiment of the invention is illustrated by  FIG. 5 , where components identical to those of the previous embodiments are indicated by the same reference numbers. According to this embodiment, head  21  of saddle holding upright  11  has a concave end  11   a  in which there is arranged the complimentarily shaped base of a block  20  that has a tubular longitudinal guide  31  rigidly connected to it. The relative position of block  30  with respect to head  21  of upright  11  makes it possible to regulate the inclination of saddle  1 . The locking of block  30  with respect to head  21  is obtained by tightening screw  22  that engages with a hollow plug  33  passing transversely through block  30 . Pin  10  is rendered integral with saddle  1  by means of fixing devices generically indicated by  34  and  35  and is slidingly mounted inside tubular guide  31 . The oscillation of saddle  1  is controlled by a mechanism  36  of the type, for example, illustrated in  FIGS. 10-12 . The sliding of saddle  1  with respect to head  21  of upright  11  is controlled by means of a pair of sheathed tension cables  37  and  38  acting in opposition to each other and remotely operated, for example by means of a small lever under the saddle generically indicated by  39 . 
   Another embodiment of the invention is illustrated by  FIG. 6 , where components identical to those of the previous embodiments are again indicated by the same reference numbers. As in the embodiments of  FIGS. 4 and 5 , this embodiment comprises a tubular guide  31  integral with a block  30  that can be tightened on head  21  of upright  11  by means of screw  22  and plug  33 . Longitudinal pin  10  is rendered integral with the saddle  1  by means of connections  34  and  35 , so that saddle  1  may slide and oscillate integrally with it. Coaxially fixed to tubular guide  31 , on one side with respect to block  30 , there is a sleeve  40 , one end of which has an axially inclined portion  40   a  obtained by removing a roughly semi-annular portion of its side wall. 
   A sleeve  42 , coaxial with sleeve  40  and integral with pin  10 , has an end  41   a  correspondingly inclined, obtained in the same manner, and counterposed to end  40   a  of sleeve  40  in such a manner that it can become coupled with it following the sliding of pin  10  controlled by a sheathed tension cable  42  connected to block  30  and capable of being operated by, for example, a small lever (not shown) situated beneath the saddle. The action of the tension cable is opposed by a spring  43  coaxial with pin  10  and arranged between the end of tubular guide  31  on the side of block  30  opposite to sleeve  40  and a stop  44  fixed to the end of pin  10 . The end of the tension cable is also attached to stop  44 . 
   When the two inclined ends  40   a  and  41   a  of, respectively, sleeves  40  and  41  have come to constitute a perfect fit as shown in  FIG. 7 , all further rotation of pin  10  within tubular guide  32  is prevented. On the other hand, as the two sleeves  40  and  41  move away from each other due to the effect of the traction applied by tension cable  42 , the amplitude of the oscillation that pin  10  is allowed to perform will increase. Spring  43  acts in opposition to tension cable  42  and therefore tends to keep the two inclined surfaces  40   a  and  41  in the position in which the form a perfect fit. 
   It should be noted that in the illustrated embodiments the seating plane of the saddle is inclined forward with respect to pin  10 , which is substantially horizontal, In practice, the rear of pin  10  will be lowered from 10 to 80 mm with respect to the seating plane of the seat  1 . 
   It should also be noted that in the embodiment illustrated by  FIGS. 5 and 6  there is provided a rearward nut  45  that can be screwed onto pin  10  and therefore makes it possible to tension soft support  1  of the seat. 
     FIG. 7  illustrates yet another embodiment of the oscillating seat in accordance with the invention that renders possible controlled oscillation and or lockage of the oscillation of the seat both in a rearward and a forward position thereof. This embodiment is particularly advantageous, above all, for sporting and competitive activities, because the advanced position of the seat is the one generally preferred for uphill routes, while the rearward position is preferred for downhill routes. The possibility of controlling the oscillation of the seat in both these positions therefore appreciably improves its performance. 
   Referring to  FIG. 7 , the saddle in accordance with this embodiment is still of the type in which there is provided a tubular guide  31  for an oscillation pin  10  integral with a block  30  mounted in an adjustable manner on head  21  of saddle-carrying upright  11  by the tightening of a bolt  22  that arrests a stem  33  passing transversely through block  30 . Fixed to the two ends of tubular guide  31  there are two sleeves  50  and  51  coaxial with pin  10  and both provided with inclined ends  50   a  and  51   a . Two further sleeves  52  and  53  integral with pin  10  and coaxial with it are provided with inclined ends  52   a  and  53   a  opposed to the respective inclined ends  50   a  and  51   a  of sleeves  50  and  51 . Two sheathed portions  54  and  55  of a single tension cable are fixed with their respective ends to stop  44  integral with one end of pin  10  and to a further stop  56  integral with the other end of the same pin  10 . The two portions  54  and  55  of the tension cable converge onto a common activation device (not shown), a lever situated under the seat for example, thanks to which it is possible at one and the same time to make pin  10  slide in tubular guide  31  and to regulate the amplitude of the oscillation, right to the point of locking it, in the two positions, i.e. respectively with the seat pushed forward or with the seat pushed backward. 
   In the configuration illustrated by  FIG. 7  the seat is pushed completely forward and all rotation is prevented by the fact that the two inclined ends  51   a  and  53   a  constitute a perfect fit. Traction applied to the portion  54  of the tension cable will produce the gradual disengagement of the aforesaid inclined ends, but will bring the inclined ends  50   a  and  52   a  closer together and eventually make them constitute a perfect fit when the saddle reaches its rearward position, where the possibility of rotation is once again prevented. In all the intermediate positions, on the other hand, oscillation will be possible with an amplitude that gradually increases as the two inclined ends  51   a  and  53   a  move away from each other in the forward position, and then gradually decreases as the inclined ends  50   a  and  52   a  come closer to each other in the rearward position. 
   With a view to making it possible for the oscillation to be locked also in a position intermediate between the completely advanced position and the completely rearward position, there is provided a locking device consisting of a tooth  57  integral with pin  10  and projecting from a slot  31   a  situated in a central position on tubular guide  31 . Locking of the rotation will be obtained when, due to the sliding of pin  10 , tooth  57  comes to be situated within a corresponding vault defined by an arched portion  30   a  of block  30  bridging over tubular guide  31 . 
   In a simplified variation of the invention, which is illustrated by  FIG. 8 , pin  10  is a threaded pin integral with saddle  1  and engaged within tubular guide  31  integral with saddle-carrying upright  11 , the tubular guide being likewise threaded on its inside. At the rearward end of pin  10  there is provided a knob  59  by means of which pin can be rotated and therefore moved forward and backward. A mechanism for adjusting and blocking the oscillation of the previously mentioned type is also provided, so that rotation of the aforesaid knob also makes it possible to adjust the amplitude of the oscillation or eventually to lock it completely. In particular, said mechanism comprises an inclined plate  60  that extends between an end of tubular guide  31  and a similarly inclined check wall  61  integral with the saddle. As inclined plate  60  approaches check wall  61  due to the translation of pin  10 , the oscillation amplitude of the pin will become gradually reduced and eventually completely locked when plate  60  fits perfectly against wall  61 . 
   Given its constructional simplicity, the oscillation mechanism shown in  FIG. 8  can also be employed for converting conventional saddle into oscillating saddle that can be adjusted in the longitudinal direction. 
   In the embodiment of the seat in accordance with the invention illustrated by  FIG. 9  the supporting structure of the saddle comprises a longitudinal groove  62  in which pin  10  is arranged in such a manner as to be able to slide. Its sliding in one direction or the other is controlled by a pair of tension cables  63  and  64  that converge on an activation device, a lever for example, similar to the one provided for the embodiments illustrated by  FIGS. 5 and 7 . Pin  10  may also rotate within groove  62  and is provided with an oscillation control and lockage mechanism generically indicated by  65 . 
   This mechanism may be of the type used in  FIGS. 10 ,  11  and  12 , According to the variation of  FIG. 10 , pin  10  has a radial rib  66  that engages with a flared groove  67 , i.e. a groove of a substantially triangular section provided on a small block  68  that can slide in a seating  69  integral with the supporting structure of the saddle. The sliding of small block  68  is obtained by rotating a screw  70  fixed with respect to seating  69  and screwed into block  68 . As the block comes gradually closer to rib  66 , the amplitude with which pin  10  is allowed to oscillate will become reduced and eventually completely locked. 
   In the variation of  FIG. 11 , on the other hand, radial rib  66  extends between a pair of adjustment screws  71  and  72  axially facing to each other and screwed into the side walls of seating  69 . In this case adjustment of the oscillation amplitude is obtained by tightening or slackening screws  71  and  72  to increase or decrease the space between them. 
   In the variation of  FIG. 12  pin  10  is provided with a groove  73  that engages with prismatic tooth  74  having a triangular section and projecting from a small block  75  that can be made to slide within seating  69  by acting on screw  70 . In this case the reduction of the oscillation amplitude of pin  10  and its eventual locking are obtained as the tooth  74  is gradually pushed further into groove  73  of pin  10 . 
   Though the present description makes reference for the most part to seats for bicycles, the invention also extends to the seats of other two-wheeled vehicles. For example, the possibility of having an oscillating seat may be advantageous in competition motorcycles, because the oscillation of the seat will accompany the rider in the bends. The oscillatory motion makes it possible to use larger and more ergonomic seats. 
   The seat in accordance with the invention can be readily dismantled by simply unscrewing screw  22  and, in the versions in which it is provided, pulling plug  33  out of block  30 , so that in this way a seat of any other shape can be mounted.