FR2889157A1 - BICYCLE SUSPENSION SYSTEM - Google Patents

Abstract

A suspension system may include a front frame connected to a front wheel (300), a shock absorber (40) pivotally connected to the front frame, and a rear frame connected to a rear wheel (600) supported by a mounting point. ground contact. The shock absorber (40) may include a predetermined pressure substantially equal to a pressure caused by the weight of the body of a cyclist. The suspension system may be structurally configured to maintain a point of instantaneous center of movement of the rear frame relative to the front frame within a range of angles of about 45degree +/- 15degree relative to the point of contact on the ground when the rear frame moves relative to the front frame.

Description

BICYCLE SUSPENSION SYSTEM

  Related Applications This application is a partial continuation and claims the benefit of US Patent Application No. 10/878 542 entitled Bicycle Rear Suspension System, filed June 29, 2004, which claims priority of Taiwanese Patent Application No. 93110661 filed on April 16, 2004. The present application also claims the priority of Taiwanese Patent Application No. 94112066 filed April 15, 2005 and Taiwanese Patent Application No. 95104571 filed February 10, 2006. The contents of all the aforementioned patent applications are incorporated. hereby by reference.

  Field of the Invention The present invention relates to a shock absorbing system. In particular, it relates to a shock absorber system of rear suspension of a bicycle.

  Background of the Invention There are a number of indices for evaluating the performance of shock absorbing systems in typical bicycle frames. For example, the effectiveness of shock damping systems can be evaluated on the basis of pedal energy loss, the effect of braking on the shock-damping action, regularity or comfort. shock damping action and pedal return caused by the shock-damping action. In the field of shock damping, the term return refers to a phenomenon in which a change in chain length subjects the rack and the pedals to the force of a rearward tension, which causes inconvenience to The cyclist.

  U.S. Patent No. 4,039,200 discloses a conventional single swing arm mechanism (which is referred to alternatively as a cantilever system) for shock damping. To reduce the pedal energy loss in this type of mechanism, the main point of rotation of a rear triangular frame with respect to a front triangular frame is designed to be adjacent to where the chain connects to the wheel. front chain. For example, if the front chain wheel group is a three-pinion group, the main point of rotation is designed to be located between the intermediate gear and the small gear in the area where the chain is connected. Alternatively, if the front chain wheel group is a two-pinion group, the main point of rotation is designed to be located where the small pinion connects to the chain. Finally, if the front chain wheel group is a single sprocket chain wheel, the main point of rotation is designed to be located where the chain wheel is connected to the chain.

  This system with a single pivoting arm nevertheless has several disadvantages. For example, although this system can reduce energy loss, it can cause a greater pedal return, especially on shock-absorbing frames with long ranges of motion. To reduce the pedal return, the height of the main point of rotation must be reduced, which causes an increase in pedal energy loss. In addition, in this system, when a cyclist pedal in a standing position, the compression of the shock absorber may change depending on the amount of force applied by the cyclist. Therefore, it is not possible to reduce the energy loss adequately during standing pedaling.

  Other existing rear suspension systems have similar problems. For example, the rear suspension system disclosed in U.S. Patent No. 5,899,480 includes a four-bar linkage. In this system, the two rotation points adjacent to the fork end are very close to each other, and a virtual pivot point (which is referred to hereinafter as VPP), which makes reference to an axis of rotation of the center of the rear wheel during operation of the bicycle, is located slightly behind the pivot point at the front end of the lower fork. Since these points are relatively close to each other, this system has many of the same disadvantages as the single swing arm mechanism described above. In these systems, the loss of pedal energy and the pedal return depend on several factors. For example, because of the height of the pivot point at the front end of the lower fork in these systems, it is not possible to achieve both low energy loss and low return. In addition, the point of instantaneous center of the rear wheel center with respect to the front triangle is lower in these systems than the resulting line of force when the rear brakes are applied. When the rear brakes are applied in systems with such a low instant center point, the resultant force stretches the rear shock absorber, which hinders the tension action of the shock absorber.

  The system disclosed in U.S. Patent No. 6,386,568 (hereinafter referred to as a 568 patent) is also problematic in many respects. For example, because of the relatively high location of the VPP, the pedaling force can generate tension on the shock absorber in a wide range of circumstances. In the system described in the '568 patent, the tension is distributed over the shock absorber when the cyclist is pedaling. The shock absorber can thus remain under constant tension. The shock absorber is nevertheless designed to act only when the impact force is greater than the tension force to which the shock absorber is subjected. As a result, the shock absorber is not necessarily capable of damping small impacts due to the constant tension exerted by the cyclist pedaling. This can cause annoyance during pedaling.

  In addition, the use of a shock absorber with non-sag adjustment in the system described in the '568 patent fails to overcome the problem of pedaling inconvenience. The term non-sag adjustment refers to a pre-set internal pressure exerted by the shock absorber which is designed to neutralize the pressure applied to the shock absorber by the weight of the cyclist's body. When a shock absorber has such a setting without sagging, it does not compress when the cyclist is sitting in the saddle.

  In addition, the fact that the instantaneous center point of the rear triangular frame with respect to the front triangular frame is largely in front of the system described in the '568 patent causes a high tension of the shock absorber when the rear brake is applied. . This tension can further prevent the shock absorber from acting effectively during braking, which causes a significant reduction in the level of comfort of the cyclist. Finally, the tension on the shock absorber in this system can unnecessarily reduce the service life of the shock absorber.

  U.S. Patent Nos. 5,553,881, 6,206,397 and 6,488,301 also disclose four-bar linkage systems. In these systems, the rear wheel path is S-shaped, and the lower half is a large projection wheel. By pedaling, the chain tension pulls the rear wheel to a certain point and thus achieves the locking effect of the shock absorbing mechanism. If this point is designed as a rear wheel center position during normal sag, it may be possible to reduce the energy loss by pedaling. However, if impacts on the ground surface occur by pedaling, impacts to the ground surface are not necessarily effectively damped by the shock absorber due to string tension constraints. As a result, the pedaling comfort can suffer. By pedaling upright, a weight transfer effect can cause the center of the rear wheel to deviate from an optimal point. This can cause the shock absorbing system's inability to effectively reduce energy loss by pedaling. In addition, the variation in the distance between the multi-purpose axle connected to the seat tube and the center point of the rear wheel (referred to as RC) can be considerable, which translates into pedal return problems.

  In light of the disadvantages of conventional shock-damping systems, there is a need for a bicycle that has a rear suspension shock absorber system that minimizes energy loss by pedaling while sitting or standing, which has minimal braking effects, which has a low pedal return, and which promotes the extension of the life of the shock absorber.

  SUMMARY OF THE INVENTION The advantages and objectives of the invention will be defined in part in the description which follows, and will be partly obvious from the description, or may be learned by practicing the invention. . In addition, the advantages and objectives of the invention will be realized and achieved by means of the elements and combinations particularly highlighted in the appended claims.

  According to one aspect of the present invention, a suspension system may comprise a front frame connected to a front wheel, a shock absorber pivotally connected to the front frame, and a rear frame connected to a rear wheel supported by a point of contact. on the ground. The shock absorber may comprise a predetermined pressure substantially equal to a pressure caused by the weight of the body relative to the front frame within angles of about 45 to ground contact when the rear frame is in relation to the front frame .

  According to another aspect of the present invention, a suspension system for a bicycle may comprise a front frame supported by a front wheel, a shock absorber connected to the front frame, a rear frame supported by a rear wheel having a center point, and a drive assembly connected to the rear frame having at least one chain wheel.

  The shock absorber may comprise a predetermined pressure substantially equal to a pressure applied to the shock absorber by a cyclist on the bicycle assembly. The rear frame can be configured to guide the movement of a virtual pivot point, which represents an axis of rotation of the center point of the rear wheel, along a path of a cyclist. The rear frame structurally configured to maintain the instantaneous center of motion of the frame may be a point backward by a range at the point of movement by substantially aligned with respect to a tangent line extending between the center point of the rear wheel and a tangent point of the chain wheel as the rear wheel moves relative to the front wheel.

  The present disclosure further provides a shock absorber for a bicycle assembly. The shock absorber comprises a main cylinder, a main piston positioned inside the main cylinder which separates the main cylinder into a first chamber and a second chamber, the first chamber and the second chamber being in fluid communication with each other. The main piston is movable between a first position and a second position, forcing a fluid to flow between the first chamber and the second chamber. The shock absorber further comprises an auxiliary cylinder which is movable along an outer surface of the main cylinder, an auxiliary piston fixed relative to the main cylinder and disposed within the auxiliary cylinder, which separates the auxiliary cylinder from a first chamber and a second chamber, and a piston rod connected between the main piston and the auxiliary cylinder. Fluid flow between the first chamber and the second chamber of the main cylinder is restricted when the main piston is in the first position.

  According to another aspect of the present invention there is provided an apparatus which, in some embodiments, comprises a front triangular frame, a rear triangular frame, a front wheel pivotally provided in a forward direction of the triangular frame, a wheel rearwardly mounted rearward of the front triangular frame, and a rearwardly extending suspension system comprising a shock absorber having a non-sag setting. The suspension system can be activated to receive a shock absorbing movement and can be installed between the front triangular frame and the rear wheel. The rear triangular frame may include a main pivot point pivotally connected to the front triangular frame. The main pivot point may be located on or near a resultant force line generated during braking and further localized by an oscillating angle within a range of 45 to 15, where the vertex of the angle can be defined as a ground contact point of the rear wheel with respect to a horizontal ground surface. The apparatus may also comprise a compression of the shock absorber not exceeding one seventh of the shock absorbing movement.

  According to yet another aspect of the present invention, there is provided an apparatus which, in some embodiments, may comprise a front triangular frame, a rear triangular frame, a front wheel pivotally provided in a forward direction of the triangular frame, a rear wheel installed in a rear direction of the front triangular frame, and a rearward extending suspension system comprising a shock absorber having a non-sag setting. The suspension system can be activated to receive a shock absorbing movement and installed between the front triangular frame and the rear wheel. The rear triangular frame may include a main pivot point pivotally connected to the front triangular frame. The main pivot point may be located on or near a resultant force line generated during braking and further localized by an oscillating angle within a range of 45 to 15, where the vertex of the angle is defined as a ground contact point of the rear wheel with respect to a horizontal ground surface. The apparatus may also comprise a compression of the shock absorber not exceeding one seventh of the shock absorbing movement. An action of the shock absorber may be responsive to an offset action to reduce energy loss. The shock absorber may further comprise a first oil chamber and a second oil chamber for receiving a pressure fluid, and a piston activated to move from a first position to a second position, the flow being restricted to the first position. The pressure fluid can flow from the second oil chamber to the first oil chamber in which the piston can move from the second position to the first position, the oil flow being restricted to the first position.

  According to yet another aspect of the present invention there is provided an apparatus which, in some embodiments, may comprise a front frame, a front wheel pivotally provided in a forward direction of the front frame, a rear wheel installed in a rearward direction of the front frame, a rearwardly extending suspension system installed between the front frame and the rear wheel, a chain wheel, and a VPP substantially aligned with a tangent formed by the center of the rear wheel and the chain wheel. The apparatus may also include moving the VPP rearward as the rear wheel moves upward.

  It is understood that the foregoing general description and the following detailed description are illustrative and explanatory only and are not restrictive of the invention as claimed.

Brief description of the drawings

  The accompanying drawings are included to provide a better understanding of the invention and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

  Other features and advantages of the invention will emerge more clearly on reading the following description, made with reference to the appended drawings, in which: FIG. 1 is a diagram of the forces applied to an existing shock damping frame before engaging the rear brakes; Figure 2 is a diagram of the forces applied to an existing shock damping frame after the rear brakes engage; Figure 3 is a schematic of the resulting line of force of the rear brakes in an existing shock damping frame; Fig. 4 is a planar diagram illustrating a first preferred embodiment of the present invention, i.e., a bicycle with rear suspension shock absorption; Fig. 5 shows how an angle is formed by the line crossing the instantaneous center point and the contact point on the ground of the rear wheel and a horizontal line corresponds to the resultant line of force in a preferred embodiment; Fig. 6 is a composite sectional diagram of a shock absorber of the preferred embodiment described above of the present invention; Fig. 7 is a rear wheel action diagram of the above-described preferred embodiment of the present invention, illustrating how shocks to the rear wheel compress in an upward direction and result in an upper connection bar and lower connecting bar to generate a pivoting action in the same direction; Fig. 8 is an action diagram of the shock absorber of the preferred embodiment described above of the present invention, illustrating how the piston moves from the first position to a second position; Fig. 9A is a virtual pivot point distribution diagram of a preferred embodiment of the present invention; Fig. 9B is a virtual pivot point distribution scheme of another preferred embodiment of the present invention; Fig. 9C is a virtual pivot point distribution diagram of another preferred embodiment of the present invention; Fig. 10 is a planar diagram of a second embodiment of a bicycle having a rear suspension shock absorption; Fig. 11 is a composite sectional diagram of a shock absorber of the second preferred embodiment of the present invention; Fig. 12 is an action diagram of a rear wheel of the second preferred embodiment of the present invention; and Fig. 13 is a composite sectional diagram of a shock absorber of the third preferred embodiment of the present invention.

  Description of Illustrative Embodiments

  Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used throughout the drawings to refer to like or similar parts.

  According to one aspect of the present invention, when a cyclist engages the brakes of a typical bicycle, the performance of a shock absorbing system can be affected in a number of ways. For example, before braking, the situation is as shown in Figure 1. Before the brakes are engaged, the force (FR), which is exerted on the rear wheel of a typical bicycle frame, can be represented by the following equations: EM ,,, -0; FRx (a b) = mgxb;

FR b nF + b where

  MPF represents a resultant torque with respect to a front point where the front wheel touches the ground; a represents the distance from a rear point where the rear wheel touches the ground to the cyclist's center of gravity; b represents the distance from the cyclist's center of gravity to the point before m represents the rider's mass; and g represents the acceleration of gravity.

  After the braking, the situation is identical to that shown in Figure 2. In this situation, the force (FR '), which is exerted on the rear wheel during braking, can be represented by the following equations.

  ## EQU1 ## where ## EQU1 ## resulting line of force (referred to as 9) can then be represented by the following equations: FF, tan 0 Fe 'xp bb _ - x rs mg t = + b -0.4-b axh bx .r a + b + ': There may be b + / 4 x --- ra - b (a + b) x (r2 + bu tall

P-tari a + b

  In general, the height of the center of gravity (h) can be estimated to be approximately equal to the wheelbase of the bicycle wheels (wb). Based on this estimate, the resulting line of force LR can form an angle of about 45 x hr with respect to a horizontal axis. Where the rear suspension system is a single swinging arm or a four-bar link having a lower fork connected to the front triangular frame by a single rotary axis, most of the main points of rotation of the rear suspension system may be located from Adjacent to or in alignment with the resulting line of force L R. Locating most major points of rotation in this manner may prevent the tension from being applied to the shock absorber when the rear brakes are engaged.

  With regard to other types of four-bar links, the instantaneous center position of the rear triangular frame with respect to the front triangular frame can be taken into account. This instantaneous center position is at the intersection of the line defined by the front and rear rotation points of the lower connecting bar and the line defined by the points of rotation of the upper connecting bar. For example, as shown in the exemplary embodiment of FIG. 5, the instantaneous center point 0 is located at the intersection of a line L1, which extends between the point of rotation before 21 and the point of rotation. rearward rotation 22 of the lower connecting bar, and a line L2, which extends between the forward rotation point 32 and the rear rotation point 31 of the upper connecting bar. The closer the instantaneous center point 0 is to the resultant line of force LR, the less action there is to affect the shock absorber.

  In a preferred embodiment of the invention, the instantaneous center point 0 is substantially aligned with the resultant line of force L R. The substantially aligned term refers to a preferred range of distances between the instantaneous center point 0 and the resultant line of force R. In another preferred embodiment of the invention, the distance between the instantaneous center point 0 and the resultant line of force LR is set to prevent a voltage being applied to the damper shock when the rear brakes are engaged. In another preferred embodiment of the invention, the instantaneous center point 0 lies within a range of 15 relative to the resultant line of force LR.

  According to another aspect of the invention, the term "weight transfer effect" refers to the change of force applied to the shock absorber which is caused by a shift of the center of gravity which occurs when a cyclist changes position between a sitting position and a standing position. As a general rule, when the cyclist changes position between a sitting position and a standing position, the center of gravity shifts, causing a change in the length of the force arm for the center of gravity relative to the rotation point of the center of gravity. the shock absorber. The change in the length of the force arm in turn causes a change in the compression of the shock absorber. In addition, when the cyclist performs a pedaling movement while standing, the center of gravity rises and falls during the pedaling movement because the feet of the cyclist do not apply a uniform force on the pedals with each pedal stroke.

  An embodiment of the invention may include a rear suspension shock absorber assembly. The rear suspension shock absorbing assembly may include a shock absorber that is responsive to certain types of forces, such as those produced by a pedaling motion of a cyclist when the cyclist is seated and standing. The shock absorber can minimize the impact of these types of forces on the efficiency of the shock shock absorber assembly. Another embodiment of the invention may include a shock absorber having a non-sag adjustment, wherein the shock absorber can act with great sensitivity to reduce energy loss. For example, this feature can improve a level of comfort of a cyclist pedaling on the bicycle set. Another embodiment of the invention may include a feature which prevents degradation of the shock absorber resulting from complete compression of the shock absorber. Another embodiment of the invention may include the reduction of pedaling energy loss and pedal feedback.

  Figure 4 illustrates an embodiment of the present invention that includes a bicycle having a rear suspension shock-damping system. The bicycle may comprise a rear suspension system 100, a front triangular frame 200, a front wheel 300, a rack unit 400, a drive unit 500, and a rear wheel 600. The front triangular frame 200 may be connected to the rear suspension system 100. The front wheel 300 may be installed at the front (the forward direction is indicated by the arrow I in FIG. 4) of the triangular frame 200. The rack unit 400 may be provided with pivotally on the base of the triangular frame 200. The drive unit 500 is adapted to be driven by the rack unit 400. The rear wheel 600 may be located at the rear (the rearward direction is indicated by the arrow II in Figure 4) of the triangular frame before 200, and installed on the rear suspension system 100.

  The front triangular frame 200 may comprise a handlebar tube 210, a seat tube 220, an upper tube 230 and a lower tube 240. The upper tube 230 may be connected between the handlebar tube 210 and the seat tube 220. lower tube 240 can be connected between the handlebar tube 210 and the seat tube 220. A multi-purpose axle 250 can be attached to a base of the seat tube 220 and connected to the lower tube 240.

  The rack unit 400 may comprise a rack 410 and two pedals 420 pivotally provided at both ends of the rack 410.

  The drive unit 500 may comprise a chain wheel assembly 510 (which is alternatively referred to as a drive assembly), a rear free wheel assembly 520, and a chain 530. The assembly The rear freewheel unit 520 can be connected to the rear wheel 600. The chain 530 can be provided around the chainwheel assembly 510 and a rear free wheel group 520.

  According to one aspect of the invention, the chain wheel assembly 510 may comprise a single pinion or a plurality of pinions. In the description of the preferred ranges of displacement of an axis of rotation of the center point of the rear wheel, the term chain wheel can refer to different things depending on the number of gears used. For example, in one embodiment where the chain wheel assembly 510 includes two sprockets, the term sprocket wheel may refer to the virtual intermediate circle 510 'which is concentric with the two sprockets and between them. In another embodiment where the chain wheel assembly 510 comprises three sprockets, the term sprocket wheel may refer to the intermediate sprockets. In another embodiment where the sprocket assembly 510 includes a single sprocket, the term sprocket wheel may refer to the single sprocket.

  The rear suspension system 100 may comprise a rear triangular frame 10, a lower connecting bar 20, an upper connecting bar 30, and a shock absorber 40. The rear triangular frame 10 may extend in a rear direction 11 through compared to the triangular front frame. The lower connecting bar 20 can pivotably connect between the rear triangular frame 10 and the front triangular frame 200. The upper connecting bar 30 can pivotably connect between the rear triangular frame 10 and the front triangular frame 200 and it can also be located above the lower connecting bar 20. The shock absorber 40 can pivotably connect between the front triangular frame 200 and the upper connecting bar 30.

  The triangular frame a lower fork 11, rear 10 may comprise an upper fork 12, and a lower end 11 may 250 and extend fork upper fork lower rear fork 13. The fork will match the multi-purpose axle in the direction back II. The 12 may be in intersection with the 11 to form an angle. The rear fork end 13 may be fixedly connected to a connection point at which the upper fork 12 and the lower fork 11 are connected. The lower fork 11 may comprise a lower fork front end 111 adjacent to the multi-purpose axle 250. The upper fork 12 may include a front upper fork end 121 above the forward end of the lower fork 111.

  The lower connecting bar 20 may comprise a first axis of rotation 21 and a second axis of rotation 22. The first axis of rotation 21 may be pivotally provided on the lower tube 240. The second axis of rotation 22 may be disposed at the opposite of the first axis of rotation 21 and pivotally provided at the front end of the lower fork 111 of the rear triangular frame 10. In addition, the first axis of rotation 21 may be located above the multipurpose axle 250 of the front triangular frame 200 and, in one embodiment, the first axis of rotation 21 is located on the side of the multipurpose axle 250 in the forward direction I. The upper connecting bar 30 may constitute a triangle having a third rotation axis 31, a pivot connection 32, and a fourth axis of rotation 33. The third axis of rotation 31 may be pivotally provided at the front end of the upper fork 121 of the rear triangular frame 10. The pivot connection 32 may be disposed opposite the third axis of rotation 31. The fourth axis of rotation 33 may be arranged between the third axis of rotation 31 and the pivot connection 32 and, in one embodiment, the fourth axis of rotation 33 may be pivotally provided on the seat tube 220.

  With reference to FIG. 6, another embodiment of the invention may comprise a shock absorber 40 having a main cylinder 41, a main piston 42, an auxiliary cylinder 43, an auxiliary piston 44, a piston rod 45, an adjustable adjusting rod 46, and a recovery unit 47. The main piston 42 may be internally disposed within the main cylinder 41. The auxiliary cylinder 43 may be externally provided around the main cylinder 41. The auxiliary piston 44 may be internally disposed within the auxiliary cylinder 43 and secured to the main cylinder 41. The piston rod 45 may be connected between the main piston 42 and the auxiliary cylinder 43 and extend along an axial line. . The adjustable adjusting rod 46 can pass through the inside of the piston rod 45. The recovery unit 47 can provide a rebound force for the main piston 42.

  In a preferred embodiment, the shock absorber 40 may have a non-sag adjustment which controls the amount of compression of the shock absorber 40. Preferably, the non-sag setting limits the amount of compression to about one seventh of a shock absorbing piston stroke. For example, if a shock-absorbing piston stroke is 38 mm, the compression amount at the non-sag setting can be 5.4 mm to 0 mm or 3.8 mm to 0 mm. When there is a small amount of compression, any pedaling force may generate a compression effect on the shock absorber 40. If the amount of compression is about zero (0), then substantially no pedaling force may be able to distribute a deactivating voltage effect on the shock absorber 40.

  The main cylinder 41 may comprise a base end 411, an upper end 412 and a main cylinder wall 413. The base end 411 may be pivotally provided on the lower tube 240 of the front triangular frame 200.

  The upper end 412 may be disposed opposite the base end 411. The main cylinder wall 413 may be disposed between the base end 411 and the upper end 412.

  In addition, the upper end 412 may comprise a small diameter portion 412 '. The base end 411 may be located on the forward direction I side of the first axis of rotation 21 of the lower connection bar 20.

  In one illustrative embodiment, the piston 42 may be formed to separate the main cylinder 41 into a first oil chamber 421 (adjacent to the base end 411) and a second oil chamber 422 (proximate the end). higher 412).

  The second oil chamber 422 may be connected to the small diameter portion 412 ', and the cross sectional area of the second oil chamber 422 may be larger than that of the small diameter portion 412'.

  In another illustrative embodiment, the auxiliary cylinder 43 may include a cylinder connecting portion 431 which fits around the outside of the main cylinder 41. The auxiliary cylinder 43 may also include a pivoting portion 432 disposed at the opposite of the cylinder connecting portion 431. The pivoting portion 432 can be pivotally connected to the pivot connection 32 of the upper connecting bar 30.

  The auxiliary piston 44 can separate the auxiliary cylinder 43 into a positive gas chamber 441 (to which it is alternatively referred as a first gas chamber), which can be located near the pivoting portion 432 and a second negative gas chamber 442 (to which is alternatively referred as a second gas chamber), which may be located near the cylinder connection portion 431. In a preferred embodiment, the pressure The air in the negative gas chamber 442 is preferably the same as the external air pressure (which is referred to alternatively as atmospheric pressure). In addition, since the air pressure of the negative gas chamber 442 may be low, the air pressure of the positive gas chamber 441 may also be similarly low.

  In another illustrative embodiment, the piston rod 45 may comprise a hollow tube. The piston rod 45 may include an oil port 451 which connects the first oil chamber 421 to the second oil chamber 422. The oil port 451 may include a first opening 452 provided on the main piston 42, and a second opening 453 provided on a peripheral surface of the piston rod 45.

  The adjusting rod 46 may comprise a conical portion 461 corresponding to the first opening 452 and pulled by a control rod 462 mounted helically on the auxiliary cylinder 43. The adjusting rod 46 can be moved along an axis to adjust the cross-sectional area of the first opening 452.

  The recovery unit 47 may comprise a spacer plug or a piston 471 and a space containing gas 472. The spacer plug 471 can fit inside the main cylinder 41.

  The gas-containing space 472 may be formed by the spacer plug 471 and located on one side of the first oil chamber 421. In one embodiment, the gas-containing space 472 may be filled with gas. high pressure nitrogen.

  In the rear suspension system described above 100 illustrated in FIG. 5, the instantaneous center point 0 of the rear triangular frame 10 with respect to the front triangular frame 200 may be substantially aligned with a point of intersection between a first straight line. L1, which passes through the first axis of rotation 21 and the second axis of rotation 22 of the lower connecting bar 20, and a second straight line L2, which passes through the third axis of rotation 31 and the fourth axis of rotation 33 of the bar In a preferred embodiment, the angle e2 is formed by the instantaneous center point 0 and the point A where the rear wheel 600 touches the ground. In another preferred embodiment, the angle e2 is about 40. In another preferred embodiment, this angle e2 is within the range of angles e1 formed by the ground surface at point A and the resultant line of force LR generated when the brake of the rear wheel 600 is applied. Therefore, it is possible to minimize the effects of shock caused by the rear wheel brake. In another preferred embodiment, the angle e1 is about 45.

  In another preferred embodiment, the angle e1 may be within the range of 40 to 50 or within the range of 35 to 45.

  As illustrated in FIG. 6, when a cyclist sits on the saddle while pedaling, and when the shock absorber has a non-sag setting, substantially no force can be delivered to the shock absorber 40 to cause it to compress or expand inadvertently. This can prevent the shock absorber 48 from being deactivated by such a force, which reduces a loss of pedaling energy. At this stage, the main piston 42 corresponds to the main cylinder 41 and is in the first position shown in FIG. 6. The second opening 453 of the oil orifice 451 corresponds to the small diameter portion 412 'of the main cylinder 41. The auxiliary piston 44 also corresponds to the auxiliary cylinder 43 and is at the lowest position.

  As further shown in Fig. 7, the rear wheel 600 may gradually swing upward in the Y direction, as when the traveling bicycle encounters uneven ground. In this embodiment, the second axis of rotation 22 of the lower connecting bar 20 can undergo a rotation offset clockwise from the rear direction II to the front direction I. As and when that the second axis of rotation 22 undergoes the offset of rotation, the first axis of rotation 21 can act as the center of rotation. The third axis of rotation 31 of the lower connecting bar 30 can also undergo a rotation offset clockwise from the rear direction II towards the front direction I. As the third axis of rotation 31 undergoes rotation offset, the fourth axis of rotation 33 can act as a center of rotation.

  As shown in the embodiment of Fig. 8, a pivot connection 32 may be used to drive the pivoting portion 432 of the auxiliary cylinder 43, causing it to compress with respect to the main cylinder 41. When the The swivel 432 is compressed, the pressure fluid flows from the first oil chamber 421 to the second oil chamber 422. The main piston 42 then moves from the first position shown in FIG. 6 to the second position near the first oil chamber 422. spacing plug 471 shown in Fig. 8. Because of the difference between the small diameter portion 412 'and the cross sectional area of the second oil chamber 422, when the second opening 453 of the oil orifice 451 is inside the small diameter portion 412 '(the main piston at the first position), a flow restriction occurs, and the main piston progressively gains e n speed from the first position to the second position. At this point, the auxiliary cylinder 43 is pressed closer to the main cylinder 41. Therefore, the auxiliary piston 44 moves from the lowest position to a higher position and compresses the high pressure gas into the main gas chamber. 41. In addition, the high pressure nitrogen inside the gas-containing space 472 can be compressed by the spacer plug 471. In other words, at the moment the shock occurs, the piston main 42 is used at the first position shown in Fig. 6 to cause flow restriction and buffer action.

  Then, when the force of the shock applied to the pivoting portion 432 of the auxiliary cylinder 43 disappears, the high pressure gas of the positive gas chamber may act to produce a rebound effect within the gas-containing space 472. The auxiliary cylinder 43 and the spacer plug 471 may bounce at the positions shown in Figures 6 and 8 for example. In addition, the piston 42 may return from the second position to the first position, and the pressure medium may be caused to flow from the second oil chamber 422 to the first oil chamber 421. In addition, because of the difference in cross sectional area of the second oil chamber 422 and the small diameter portion 412 ', when the second opening 453 of the oil port 451 corresponds to the small diameter portion 412', the restriction of flow can be performed. The movement of the main piston 42 progressively slows as the piston moves from the second position to the first position. In this way, it is possible to prevent the shock absorber 40 from bouncing and the auxiliary piston 44 not to strike the auxiliary cylinder 43. Thus, the operating life of the shock absorber 40 can be extended. .

  In another embodiment, the gas pressure in the negative gas chamber 422 of the shock absorber 40 is preferably low. The gas pressure of the positive gas chamber 441 may be correspondingly low. This can reduce manufacturing costs since the requirements for precision and air tightness can be reduced. In addition, the low gas pressure of the positive gas chamber 441 can provide a higher level of comfort. By using the control rod 462, the cross-sectional area between the conical portion 461 and the first aperture 452 can be adjusted to adjust the buffer performance as needed.

  As further shown in FIGS. 4 and 9A-C, when a pedaling force is applied to a pedal 420, the tension on the chain 530 and the weight rotation of a cyclist can distribute a force to the pedal. end of the rear fork 13. This force can be applied in different directions, for example depending on the gear. When the VPP is located on the average of all the lines of force applied, a lower amount of pedaling energy loss occurs. In one embodiment, the VPP is substantially aligned with a tangent line extending from the center 602 of the rear wheel 600 assisting a sprocket 510 when a cyclist is in a normal position and when the shock absorber has a setting without sag. Figures 9A-C illustrate the range of motion of the VPP under different circumstances. For example, as the rear wheel 600 continues to swing upward in the Y direction, for example away from the ground surface, the VPP extends in the direction II. It is thus possible to reduce the effect of pedal return caused when the shock absorber is in action. In one embodiment, the VPP is on or near a tangent line 512 of a rear wheel center 602 and a chain wheel 510. The range of motion of the VPP may be defined by reference to the tangent point 514 and the tangent line 512 of the rear wheel center 602 to the chain wheel 510.

  As illustrated in the embodiment of Fig. 9B, the range of motion of the VPP may be within an area 610. Area 610 may be delimited by a first vertical line 612, a second vertical line 614 , deflection distances up and down H1 and HZ with respect to the tangent line 512, an upper line 616 and a lower line 618. The upward deflection distance H1 may extend to a first deflection point P which is on the second vertical line 614 and which is spaced above the tangent line 512. Similarly, the downward deflection distance HZ can extend to a second deflection point P2 , which is located on the second vertical line 614 and which is spaced below the tangent line 512. The zone 610 may also be delimited by a third deflection point P3, which is on the first vertical line 612 and which is spaced at above the tangent line 512, and a fourth deflection point P4 which is on the first vertical line 612 and which is spaced below the tangent line 512. The upper line 616 may extend along a direction parallel to the tangent line 512 and may extend between the first deflection point P and the third deflection point P3. Similarly, the lower line 618 may extend between the second deflection point P2 and the fourth deflection point P4.

  The tangent point 514 may be spaced a distance D1 from the first vertical line 612 extending through a center point C of the chain wheel 510. The second vertical line 614 may be spaced from the tangent point 514 of a distance D2. In an illustrative embodiment, the distance D1 is about 10 mm, the distance D2 is about 300 mm, the deflection distances up and down H1, HZ are 55 mm respectively, and both parallel lines 616 and 618 may extend along a direction substantially parallel to the tangent line 512.

  As illustrated in the embodiment of Fig. 9C, the range of motion of the VPP may be within an area 620. Area 620 may be delimited by a first vertical line 622 intersecting with the tangent point 514, a second vertical line 624, upward and downward deflection distances H3 and H4 relative to the tangent line 512, an upper line 626 and a lower line 628. The upward deflection distance H3 may be extend to a first deflection point P'1 which is on the second vertical line 624 and which is spaced above the tangent line 512. Similarly, the deflection distance downward H4 can extend to a second deflection point P'2, which is located on the second vertical line 624 and which is spaced below the tangent line 512. The zone 620 may also be delimited by a third deflection point P'3 , which is on the first vertical line 622 and which is spaced above the tangent line 512, and a fourth deflection point P'4 which is on the first vertical line 622 and which is spaced below the tangent line 512. The line upper 626 may extend between the first deflection point P'1 and the third deflection point P'3. Similarly, the lower line 628 may extend between the second deflection point P'2 and the fourth deflection point P'4. In an illustrative embodiment, the distance D is about mm, the deflection distances up and down H3, H4 are 20 mm respectively, and the two parallel lines 626 and 628 may extend along a direction substantially parallel to the tangent line 512. By way of further illustration, the embodiments of the present invention may provide at least the following exemplary functions.

  1. minimize the pedaling energy loss: the VPP is placed near or on the tangent defined by the rear wheel center and the front chain wheel. As a result, the system can effectively reduce the torque generated by the chain tension by pedaling on the VPP, which minimizes the compression of the shock absorber 40.

  II. Effective shock absorption: thanks to the non-sag adjustment of the shock absorber 40, when a cyclist sits on the saddle and pedal, the shock absorber 40 can not act or can act only slightly. Thus, the goal of low energy loss is realized. Nevertheless, when the bicycle passes over a bump or a hole, it can respond quickly.

  III. The impact damping based on the position of the cyclist: due to the weight transfer effect, when a cyclist pedal while standing, the force applied by the cyclist on the shock absorber 40 is different from the force applied when the cyclist is seated. If there is the setting without sagging, the shock absorber 40 performs a less shock damping action when the cyclist applies a pedaling force and when the bicycle hits an object on the road than would be the case if the bicycle had a shock-damping design with sag adjustment.

  Thus, it is possible to significantly reduce the energy loss by pedaling upright.

  IV. Minimize the impact of the braking on the shock absorption: the instantaneous center point 0 of the rear triangular frame 10 with respect to the front triangular frame 200 being inside the sector 45 whose summit is the point where the wheel With the rear end touching the ground and the horizontal line of which is the ground surface, the effects of shock caused by the braking of the rear wheel can be minimized.

  V. Minimizing Pedal Return: Since the pedal return phenomenon can be caused by changes in chain length during the shock-damping action, the RC change can be changed so that it approximates the change in chain length. The phenomenon of pedal return can thus be minimized.

  VI. Providing a shock absorber with a non-sag adjustment function: since a shock absorber 40 may be provided with a positive gas chamber 441 which has a certain predetermined internal pressure level, the shock absorber 40 may have a characteristic adjustment without sag. When this predetermined pressure in the gas chamber 441 is high, the shock absorber 40 may preferably have a very solid design, and it may not respond too quickly. As indicated by the equation PP = Np + F (PP = gas pressure of the positive gas chamber, Np = gas pressure of the negative gas chamber, F = force applied by the cyclist's weight), the Pressure reduction objective in the positive gas chamber 441 can be achieved by reducing the pressure in the negative gas chamber 442. When the pressure in the negative gas chamber 442 is relatively low, perhaps as low as the external pressure it is possible to obtain the ideal pressure of the positive gas chamber 441.

  Nevertheless, when the pressure in the negative gas chamber 442 is low, the result is that the shock absorber 40 tends to bounce at its limit. When the shock absorber piston stroke reaches its limit, the moving parts of the shock absorber 40 strike against each other and tend to become damaged. Therefore, the shock absorber 40 uses a hydraulic bumper, which can generate a buffer effect when the rebound stroke of the shock absorber piston is about to reach its limit, which can extend the life of the shock absorber. It goes without saying that this solution does not have to use hydraulic parts. Any material or process capable of achieving an elastic buffer effect can provide the same results.

  As further shown in Fig. 10, a second embodiment of the present invention is similar to the embodiments described above. This embodiment comprises a rear suspension system 100 ', a front triangular frame 200' pivotally connected to the rear suspension 100 ', a front wheel 300' installed at the front (the forward direction is indicated by the arrow I in FIG. 10) of the front triangular frame 200 ', and a rear wheel 600' corresponding to the front wheel 300 'and situated at the rear (the direction towards the rear is indicated by the arrow II in the figure 10) of the triangular frame before 200 'and installed on the rear suspension system 100'.

  The triangular frame before 200 'may comprise a handlebar tube 210', a seat tube 220 ', an upper tube 230' connected between the handlebar tube 210 'and the seat tube 220', a lower tube 240 'connected between the handlebar tube 210 'and the seat tube 220' and below the upper tube 230 ', a multipurpose axle 250' connected to a base of the lower tube 240 ', and a pivot post 260' with respect to the seat tube 220 'and disposed above the multi-purpose axle 250'. The rear suspension system 100 'comprises a rear triangular frame 10' pivotally connected to the pivot post 260 ', and a shock absorber 40' pivotally connected between the front triangular frame 200 'and the rear triangular frame 10 .

  The rear triangular frame 10 'may comprise a main pivot point 11' pivotally connected above the multipurpose axle 250 '.

  As shown in FIG. 11, the shock absorber 40 'may comprise a main cylinder 41', a main piston 42 'entering inside the main cylinder 41', an auxiliary cylinder 43 'adapted to the outside of the main cylinder 41 ', an auxiliary piston 44' entering inside the auxiliary cylinder 43 'and fixed on the main cylinder 41', a piston rod 45 'connected between the main piston 42' and the auxiliary cylinder 43 'and extending along an axis, an adjustable adjusting rod 46 'passing through the interior of the piston rod 45', a recovery unit 47 'which provides a rebound force for the main piston 42', and a buffer portion 48 'installed within a negative gas chamber 442' of the auxiliary cylinder 43 '. The stamp portion 48 'may comprise a ring made of high quality plastics material. When the shock absorber 40 'has a non-sag adjustment, no pedaling force is able to generate a voltage on the shock absorber 40'. In addition, the structural parts and functions described above are broadly similar to those of the shock absorber of the embodiments described above as shown in FIGS. 1-9. In addition, the buffer portion 48 'can produce buffer effects when the rebound stroke of the shock absorber reaches or is about to reach its limit.

  Thus, it can extend the operating life of the shock absorber.

  With the main pivot point 11 'at or near the resulting LR force line generated when the brakes are applied to the rear wheel 600', the tension force produced on the shock absorber 40 'by the pedaling force applied by the cyclist sitting on the saddle can be reduced to a minimum.

  As further shown in Fig. 12, when the bicycle encounters an uneven road surface which causes the rear wheel 600 'to swing gradually in a upward direction Y, the rear triangular frame 10' undergoes, along with the point main pivot 11 'as a center of rotation, a rotation offset from the rear direction II to the forward direction I (clockwise). In addition, by positioning the shock absorber 40 ', it is possible to achieve the flux and buffer restriction effects (as has been described in the same shock absorber action of the previous embodiments).

  The shock absorber 40 'may also be applied to the rear suspension system 100 of the embodiments shown in FIGS. 4 and 5. The shock absorber 40 of the foregoing embodiments may be applied to the rear suspension system 100' of the embodiment shown in FIG.

  As shown in FIG. 13, the shock absorber 40 "according to another embodiment of the present invention is generally the same as that of the preceding embodiments. In the previous embodiments, the shock absorber 40 is provided with a negative gas chamber 442, whose gas pressure is low, In the shock absorber 40 "shown in Fig. 13, the pressure of the negative gas chamber 442" is substantially equal to the pressure external (atmospheric pressure), and the location where the main cylinder 41 "is connected to the auxiliary cylinder 43" is provided with a plurality of conduction channels 48 ", and by means of the conduction channels 48", the gas chamber negative 442 "can be connected externally.

  The above descriptions are only preferred embodiments of the present invention and should not be used to limit the scope of the embodiments of the present invention. This means that any equivalent change or equivalent revision made in accordance with the claims and the description of the present invention must be considered within the scope of the present invention.

  Other embodiments of the invention will be apparent to those skilled in the art in view of the disclosure and practice of the invention disclosed herein. The paper and the examples should be considered as purely exemplary. It is therefore understood that the invention is not limited to the illustrative examples of the present specification. Instead, the invention is intended to cover all modifications and variations within the scope of the appended claims and their equivalents.

Claims (49)

  A suspension system characterized by comprising: a front frame connected to a front wheel (300); a shock absorber (40) pivotally connected to the front frame and having a predetermined pressure substantially equal to a pressure caused by the weight of the body of a cyclist; and a rear frame connected to a rear wheel (600) supported by a ground contact point, and structurally configured to maintain a point of instantaneous center of movement of the rear frame with respect to the front frame within a range of angles about 45 to the point of ground contact as the rear frame moves relative to the front frame.   Suspension system according to claim 1, characterized in that the instantaneous center of movement comprises a point of center of rotation of the rear frame with respect to the front frame, and the front and rear frames are connected to each other. another at a plurality of axes of rotation which define the instantaneous center point of rotation.   3. Suspension system according to claim 1, characterized in that the front and rear frames are connected to each other at a first axis of rotation, a second axis of rotation, a third axis of rotation, and a fourth axis of rotation, and the instantaneous center of movement of the rear frame relative to the front frame is substantially aligned with a point of intersection between a first line, which extends through the first axis of rotation and the second axis of rotation, and a second line, which extends through the third axis of rotation and the fourth axis of rotation.   4. Suspension system according to claim 3, characterized in that the first axis of rotation and the second axis of rotation connect a lower connecting bar of the rear frame to the front frame.   5. Suspension system according to claim 3, characterized in that the third axis of rotation and the fourth axis of rotation connect an upper connecting bar of the rear frame to the front frame.   Suspension system according to claim 1, characterized in that it further comprises a chain wheel rotatably coupled to the rear wheel (600), and characterized in that the rear frame is configured to substantially align the movement a virtual pivot point, which represents an axis of rotation of a center point of the rear wheel (600), relative to a line extending between the center point of the rear wheel (600) and a tangent point of the wheel chain.   7. suspension system for a bicycle characterized in that it comprises: a front frame supported by a front wheel (300); a shock absorber (40) connected to the front frame, and having a predetermined pressure substantially equal to a pressure applied to the shock absorber (40) by a cyclist of the bicycle assembly; a rear frame supported by a rear wheel (600) having a center point; a drive assembly connected to the rear frame having at least one chain wheel; and wherein the rear frame is configured to guide the movement of a virtual pivot point, which represents an axis of rotation of the center point of the rear wheel (600), along a substantially aligned path with respect to a a tangent line extending between the center point of the rear wheel (600) and a tangent point of the chain wheel when the rear wheel (600) moves relative to the front wheel (300).   Suspension system according to claim 7, characterized in that it further comprises a lower connecting bar pivotally connected to the front frame at a front pivot point and the rear frame at a rear pivot point, and a upper connecting bar pivotally connected to the front frame at a front pivot point and the rear frame at a rear pivot point, and wherein a point of intersection of a first line, which is defined by the pivot points front and rear of the lower connecting bar, and a second line, which is defined by the front and rear pivot points of the upper connecting bar, remains within a range of angles of about 45 relative to a ground surface, wherein the angle range has an apex at a ground contact point of the rear wheel (600).   Suspension system according to claim 7, characterized in that the rear frame is configured to guide the movement of the virtual pivot point within an area delimited by a first vertical line extending through a point of rotation. center of the chain wheel, a second vertical line spaced from the first vertical line towards the rear wheel (600), a first deflection point on the second vertical line and spaced above the tangent line, a second deflection point on the second vertical line and spaced below the tangent line, a third deflection point on the first vertical line and spaced above the tangent line, a fourth deflection point on the first vertical line and spaced below the tangent line, an upper line extending between the first deflection point and the third deflection point, and a lower line extending between the second point of deviation and the fourth point of deviation.   10. Suspension system according to claim 9, characterized in that the upper line and the lower line extend in a direction substantially parallel to the tangent line.   11. Suspension system according to claim 9, characterized in that the tangent point is spaced about 10 mm from the first vertical line, the first point of deflection is spaced about 55 mm above the tangent line, the second The deflection point is spaced about 55 mm below the tangent line, and the second vertical line is spaced about 300 mm apart from the tangent point.   Suspension system according to claim 7, characterized in that the rear frame is configured to guide the movement of the virtual pivot point within an area delimited by a first vertical line extending through the tangent point. of the chain wheel, a second vertical line spaced from the first vertical line, a first deflection point on the second vertical line and spaced above the tangent line, a second deflection point on the second vertical line and spaced below from the tangent line, a third deflection point on the first vertical line and spaced above the tangent point, a fourth deflection point on the first vertical line and spaced below the tangent point, an upper line extending between the first tangent line and point of deviation and the third point of deflection, and a lower line extending between the second deflection point and the fourth point of deviation.   13. Suspension system according to claim 12, characterized in that the upper line and the lower line extend in a direction substantially parallel to the tangent line.   A suspension system according to claim 12, characterized in that the first deflection point is spaced about 20 mm above the tangent line, the second deflection point is spaced about 20 mm below the the tangent line, and the second vertical line is spaced about 150 mm away from the first vertical line.   Suspension system according to claim 7, characterized in that the drive assembly comprises an intermediate gear having an outer circumference intersecting the tangent point.   16. Suspension system according to claim 7, characterized in that the drive assembly comprises two gears, and the tangent point is located on a circumference of a virtual intermediate circle between the two gears.   Suspension system according to claim 7, characterized in that the chain wheel assembly comprises a single pinion, and the tangent point is located on a circumference of the single pinion.   Suspension system according to claim 7, characterized in that the shock absorber (40) comprises: a main cylinder (41) having a first chamber and a second chamber in fluid communication with the first chamber; and a main piston (42) configured to move between a first position, at which fluid is present in the first chamber, and a second position, at which fluid is moved from the first chamber to the second chamber.   Suspension system according to claim 18, characterized in that the flow of fluid between the first chamber and the second chamber is restricted when the main piston (42) is in the first position.   Suspension system according to claim 18, characterized in that the shock absorber (40) further comprises: a passage between the first chamber and the second chamber of the main cylinder (41), the passage having a first connected opening in the first chamber and a second opening connected to the second chamber; and wherein when the main piston (42) is in the first position, the second opening is located within a portion of the second chamber having a relatively smaller diameter to restrict the flow of fluid exiting the second opening.   Suspension system according to claim 18, characterized in that the shock absorber (40) further comprises: an auxiliary cylinder (43) movable along an outer surface of the main cylinder (41); an auxiliary piston (45) attached to the main cylinder (41) and disposed within the auxiliary cylinder (43) to define a first chamber and a second chamber; and a piston rod (45) connected to the main piston (42) and the auxiliary cylinder (43).   22. Suspension system according to claim 21, characterized in that the fluid flow between the first chamber and the second chamber is restricted when the main piston (42) is in the first position.   Suspension system according to claim 22, characterized in that the shock absorber (40) further comprises: a passage between the first chamber and the second chamber of the main cylinder (41), the passage having a first opening connected thereto to the first chamber and a second opening connected to the second chamber, and wherein when the main piston (42) is in the first position, the second opening is located within a portion of the second chamber having a relatively smaller diameter to restrict the flow of fluid exiting the second opening.   A suspension system according to claim 21, characterized in that the piston rod (45) is movable within an internal hole so as to adjust a cross-sectional area of the first opening.   25. Suspension system according to claim 21, characterized in that the first chamber of the auxiliary cylinder (43) is supplied with the predetermined pressure so that when a cyclist is on the suspension system, the amount of compression of the shock absorber (40) caused by the weight of the cyclist is about one seventh of a shock absorbing piston stroke of the shock absorber (40).   26. A suspension system according to claim 21, characterized in that the shock absorber (40) comprises a pressure in the second chamber of the auxiliary cylinder (43) which is substantially equal to atmospheric pressure.   27. Suspension system according to claim 21, characterized in that the second chamber of the auxiliary cylinder (43) is in fluid communication with an outer portion of the auxiliary cylinder (43).   The suspension system of claim 21, characterized in that the shock absorber (40) further comprises a buffer portion installed within the second chamber of the auxiliary cylinder (43).   Suspension system according to claim 21, characterized in that the shock absorber (40) further comprises a spacer plug disposed within the main cylinder (41) so as to define a space containing fluid to contain a fluid inside it.   Suspension system according to claim 7, characterized in that the rear frame is configured in such a way that during a first half of a complete shock absorbing piston stroke of the shock absorber (40). , an instantaneous center of movement of the rear frame with respect to the front frame remains within a range of angles of about 45 to a ground area, where the range of angles has a one-to-one peak. ground contact point of the rear wheel (600).   31. Suspension system according to claim 7, characterized in that the rear frame is configured so that during a first third to two thirds of a full stroke of the shock absorbing piston of the shock absorber (40), an instantaneous center of movement of the rear frame with respect to the front frame remains within a range of angles of about 45 to a ground surface, where the range of angles at a vertex at a ground contact point of the rear wheel (600).   32. Rear suspension system (100) for a bicycle having a front frame supported by a front wheel (300), characterized in that it comprises: a shock absorber (40) connected to the front frame; and a rear frame supported by a rear wheel (600) and connected to the front frame of the bicycle at a plurality of pivot points arranged to maintain a central pivot axis of the rear frame with respect to the front frame within a Angle range of about 45 to a ground contact point of the rear wheel (600).   The rear suspension system (100) according to claim 32, characterized in that the rear frame comprises a lower connecting bar and an upper connecting bar, and the plurality of pivot points comprises a first pivot point and a second pivot point. pivot point between the lower connecting bar and the front frame, and a third pivot point and a fourth pivot point between the upper connecting bar and the front frame.   A rear suspension system (100) according to claim 32, characterized in that the shock absorber (40) is provided with a predetermined pressure substantially equal to a pressure caused by the weight of a cyclist's body on the body. shock absorber (40) when the cyclist is on the rear suspension system (100).   The rear suspension system (100) according to claim 32, characterized in that it further comprises: a chain wheel assembly having at least one pinion mounted on the front frame, the chain wheel assembly having a concentric virtual circle concentric with the at least one pinion, the virtual intermediate circle being located at an intermediate position of the at least one pinion, and having a mean diameter substantially equal to a diameter of the at least one pinion; and wherein the rear frame is configured to guide a movement of a virtual pivot point, which represents an axis of rotation of the center point of the rear wheel (600), along a path substantially aligned with a tangent line extending between a center point of the rear wheel (600) and a tangent point on the virtual intermediate circle.   36. A rear suspension system (100) according to claim 35, characterized in that the chain wheel assembly comprises three pinions, and the virtual intermediate circle is substantially coincident with an outer circumference of the intermediate gear.   37. Rear suspension system (100) according to claim 35, characterized in that the chain wheel assembly comprises two gears, and the virtual intermediate circle is substantially coincident with an intermediate circle between the two gears.   38. A bicycle assembly according to claim 35, characterized in that the chain wheel assembly comprises a pinion, the virtual intermediate circle being substantially coincident with an outer circumference of the pinion.   39. A bicycle assembly characterized by comprising: a front frame supported by a front wheel (300); a suspension system having a rear frame supported by a rear wheel (600), a shock absorber (40) pivotally connected between the front frame and the rear frame, the shock absorber (40) having a predetermined internal pressure substantially equal to a pressure caused by the weight of a cyclist's body on the shock absorber (40) when the cyclist is on the bicycle assembly, the rear frame being pivotally connected to the front frame at a point main pivot located on or near a resultant force line generated by gravity and friction during braking; and wherein the main pivot point is within a range of angles of about 45 relative to a ground surface, where the vertex of the angle range is at a point of contact on the ground of the rear wheel (600).   40. A bicycle assembly according to claim 39, characterized in that a pedaling force applied by a cyclist causes substantially no tension on the shock absorber (40).   A bicycle assembly according to claim 39, characterized in that the main pivot point lies within a range of angles of about 35 to 45 with respect to the ground surface, where the vertex of the angle range is at the ground contact point of the rear wheel (600).   42. A shock absorber (40) for a bicycle assembly characterized by comprising: a main cylinder (41); a main piston (42) positioned within the main cylinder (41), characterized in that the main piston (42) separates the main cylinder (41) into a first chamber and a second chamber, the first chamber and the second chamber chamber being in fluid communication with each other, and characterized in that the main piston (42) is movable between a first position and a second position, forcing a fluid to flow between the first chamber and the second chamber; an auxiliary cylinder (43) movable along an outer surface of the main cylinder (41); an auxiliary piston (45) fixed to the main cylinder (41) and disposed within the auxiliary cylinder (43), characterized in that the auxiliary piston (45) separates the auxiliary cylinder (43) into a first chamber and a second bedroom; a piston rod (45) connected between the main piston (42) and the auxiliary cylinder (43); and wherein the flow of fluid between the first chamber and the second chamber of the main cylinder (41) is restricted when the main piston (42) is in the first position.   43. A bicycle assembly according to claim 42, characterized in that the shock absorber (40) has a passage connecting the first chamber and the second chamber of the main cylinder (41), the passage having a first opening connected to the first bedroom and a second opening connected to the second bedroom; and wherein when the main piston (42) is in the first position, the second opening is located within a portion of the second chamber of the main cylinder (41) having a relatively smaller diameter to restrict flow fluid leaving the second opening.   A shock absorber (40) according to claim 42, characterized in that the piston rod (45) defines an internal hole, and further comprises a rod movable within the internal hole, the rod being adapted to adjust the cross-sectional area of the first opening.   The shock absorber (40) of claim 42, further comprises a buffer portion installed within the second chamber of the auxiliary cylinder (43).   A shock absorber (40) according to claim 42, characterized in that the first chamber of the auxiliary cylinder (43) is provided with a predetermined pressure substantially equal to a pressure caused by the weight of the body of a cyclist on the shock absorber (40) when the cyclist is on the bicycle assembly.   47. A shock absorber (40) according to claim 42, characterized in that a pressure of the second chamber of the auxiliary cylinder (43) is substantially equal to atmospheric pressure.   48. Damper (40) according to claim 42, characterized in that the second chamber of the auxiliary cylinder (43) is in fluid communication with an outer portion of the auxiliary cylinder (43).   A shock absorber (40) according to claim 42, characterized in that the shock absorber (40) further comprises a spacer plug which fits inside the main cylinder (41) and a space containing fluid formed by the spacer plug and the main cylinder (41).