FR2887000A1 - Mechanical energy absorber for bicycle frame comprises fluid-filled chamber with supple inner membrane between two separate compartments - Google Patents

Abstract

The energy absorber consists of a fluid-filled chamber mounted between components (A, B) that are able to move relative to one another, divided into two compartmemnts that are separated by a supple membrane, e.g. of an elastomer-coated glass fibre fabric. The chamber is connected by a tube to a second divided chamber containing fluid on one side of a membrane and air at variable pressure on the other, designed to damp shocks and vibrations. The fluid can be water, an aqueous mixture or a lubricant.

Description

The present invention relates to a device for absorbing energy

  mechanical fluid, for cycles and cycle transport accessories, for limiting the energy transfer between two parts or sets (A) and (B) whose movement

  relative is limited by one or more mechanical links (L) and whose range of motion in the remaining degrees of freedom is limited. This type of connection is present in the rear suspension linkages / swingarms, the slide links in the cycle forks, the link between frames / accessories such as baby carriers and even in the suspensions of cycle trailers.

  The fluid energy absorbing devices currently used on the cycles are of the type movable piston in a chamber. These devices may have disadvantages in terms of their cost and their weight. In the case of a relative movement of the two said parts or sets (A) and (B) non-linear, the conventional absorption devices are secured to each of said two parts or sets (A) and (B) by the intermediate pivots or ball joints of a weight and a significant cost.

  In addition, the presence of sliding contacts (piston in chambers), requires the use of a lubricant fluid in the absorber. The device according to the invention can remedy these disadvantages. According to a first characteristic, it comprises a volume (V1) whose boundaries are defined by two surfaces, defined by one or more bodies, preferably rigid, contiguous to each of said elements or sets (A) and B) whose relative movement is limited, on which they can be secured by means of element (s) or assembly technique, and a flexible membrane connecting the two said adjoining surfaces, capable of deforming to leave the two said parts or together the desired amplitude of movement, and a volume (V2) whose capacity varies as a function of the pressure of the fluid that it contains and whose amplitude of variation is at least equal to the amplitude of variation of (V1 ) between the two extreme positions of the relative movement of said two pieces or sets (A) and (B) whose relative movement is limited, said volumes (V1) and volume (V2) are related by means of at least one orifice or conduit [ for the case of a mounting or the said (V1) and (V2) are distant, in which case the said (V2) is associated without any rigidity constraints to one or other of the two said parts or sets whose relative movement is limited], allowing the fluid they contain to circulate freely or controlledly between said volume (V1) and volume (V2), and one or more openings (s) closed in operating condition can be placed on one or / and the other of said volume (V1) and volume (V2), or on said conduit can connect them to add or remove fluid in said volumes.

  According to particular embodiments: the relative movement between said parts or assemblies (A) and (B) may be limited by one or more links of the pivot or slide type according to an amplitude that can be limited by stops mechanical, which can be made of elastomer.

  - The said volume (V2) may be defined by a flexible elastic membrane or not able to be constrained by an elastic body (more particularly in the case where the said membrane is inelastic), associated or not with a body (s) rigid to define its boundaries.

  the fluid contained in said volumes (VI) and (V2) may be water, an aqueous mixture or a lubricant.

  - The circulation of the fluid between said volumes (V1) and (V2) can be controlled in particular on its flow, and differently depending on the direction of flow of said fluid, for example by means of a check valve with throttling, which can be adjustable and / or controlled by fluid pressure.

  Non-elastic flexible membranes may be coated fabric membranes, for example a fiberglass cloth coated with elastomer.

  - The elastic flexible membranes may be elastomeric membranes.

  - The elastic body constraining the flexible membrane, boundary of said volume (V2) may be a metal spring, an elastomeric spring, a spring of composite materials, a gas under pressure whose quantity is fixed or adjustable, a deformable element containing a gas under pressure whose quantity is fixed or adjustable exerting on it a fixed or adjustable pressure.

  - The pressurized gas whose quantity is fixed or adjustable exerting on said flexible membrane, boundary of said volume (V2) a stress, directly or through a deformable body containing it may be air or nitrogen.

  - The flexible membranes can be protected, especially against perforations by covers or bellows.

  The accompanying drawings illustrate the invention: Figure la: Representation of a cycle frame with swingarm, on which the device can be adapted.

  Figure lb: Representation of a telescopic front fork cycle, on which the device can be adapted.

  Figure 2: Partial representation of the device in a particular application of damper for oscillating arm with (V 1) and (V 2) remote, (V 1) using for the definition of its borders rigid bodies and a flexible non-elastic membrane.

  FIG. 3: Partial representation of the device in a particular application of a swingarm damper with (V1) and (V2) remotes, (V2) using for the definition of its borders rigid bodies and a flexible non-elastic membrane constrained by a gas under pressure.

  Figure 4: Representation of the device in a particular application of shock absorber for swingarm with (V 1) and (V2) remote.

  With reference to these drawings, the device comprises: A volume (V1) whose boundaries are defined by: - two surfaces, one contiguous to each of said two pieces or sets (A) and (B) whose relative movement is limited; One (Si) defined by a rigid metal washer and the screw (K) securing it to a protruding part (P), welded to the oscillating arm (B) and used to clamp the membrane (Ml) on said prominent piece (P) The other, (S2) defined by a part (Q) forming a welded bowl on the frame (A) - A flexible membrane (Ml) connecting the two said adjacent surfaces (Sl) and (S2), capable of to deform to leave the swing arm (B) the desired range of motion.

  A volume (V2) whose capacity varies as a function of the pressure of the fluid that it contains and whose amplitude of variation is at least equal to the amplitude of variation of (V1) between the two extreme positions of the oscillating arm ( B).

  The volume (V2) is defined by a non-elastic flexible membrane (M2) clamped between two metal bells (L1) and (L2) by means of screws (J), one of the two bells (L1) defining a rigid part at the borders of (V2), the other of the two bells (L2) defining a rigid part at the borders of a volume containing pressurized air (G), which exerts a stress on the membrane (M2).

  Volumes (V1) and (V2) being distant, a conduit (C) puts them in relation and allows the fluid contained in volumes (V 1) and (V 2) to flow between said volume (V 1) and volume ( V2).

  The circulation of the fluid between said volumes (V1) and (V2) is controlled on the flow, and differently according to the direction of flow of said fluid by means of two adjustable non-return valves with choke (D) positioned on the duct ( VS).

  The elements constituting the volume (V2) are associated with the frame (A) by means of one of the screws (J) used to clamp the membrane between the two bells (L1) and (L2).

  An orifice (0) closed in operating condition by targeted caps (Ni) and (N2) are placed on each of said volume (V1) and volume (V2), to allow the user to add or remove fluid in the said volumes.

  The relative movement between the frame (A) and the oscillating arm (B) is limited by a link (L) of the pivot type according to an amplitude limited by mechanical stops (E) made of elastomer.

  The quantity of air under pressure (G) contained in the volume allotted to it is modifiable by a valve (I).

  The fluid contained in the volumes (V 1) and (V 2) is water.

  The flexible membranes (Ml) and (M2) are elastomeric coated fiberglass fabric membranes.

  The flexible membrane (Ml) is protected, in particular against the perforations by a bellows (H). -6

Claims (8)

  1 - Mechanical fluid energy absorption device, for cycles and cycle transport accessories, for limiting the energy transfer between two parts or assemblies (A) and (B) whose relative movement is limited by one or more mechanical links (L) and whose amplitude of movement in the remaining degrees of freedom is limited, characterized in that it comprises a volume (V 1) whose boundaries are defined by two surfaces (S 1) and (S2), defined by one or more bodies, preferably rigid, one contiguous to each of said two pieces or sets (A) and (B) whose relative movement is limited, on which they can be secured by means of element (s) or technique (s) assembly, and a flexible membrane (Ml) connecting the two said adjacent surfaces, capable of deforming to leave the two said pieces or together the desired range of motion, and a volume (V2 ) whose capacity varies ion of the pressure of the fluid that it contains and whose amplitude of variation is at least equal to the amplitude of variation of (V1) between the two extreme positions of the relative movement of the two said parts or assemblies whose relative movement is limited, the said volumes (V 1) and volume (V2) are related by means of at least one orifice or conduit (C) [for the case of a mounting or the said (V1) and (V2) are distant , in which case said (V2) is associated, without imperative rigidity constraints to one or the other of said two parts or sets whose relative movement is limited], allowing the fluid they contain to circulate so free or controlled between said volume (V1) and volume (V2), and an orifice (s) (s) closed in operating condition can be placed on one or the other of said volume (V1 ) and volume (V2), or on said conduit (C) can connect them to add or remove fluid in said volumes.   2 - Device according to claim 1 characterized in that the relative movement between said parts or sets (A) and (B) can be limited by one or more links (L) of the pivot or slide type according to an amplitude which can be limited by mechanical stops (E), which can be made of elastomer.   3 - Device according to claim 1 is characterized in that said volume (V2) can be defined by a flexible membrane (M2) elastic or not can be constrained by an elastic body (G) (more particularly in the case where the said membrane is non-elastic), associated or not with rigid body (s) to define its boundary.   4 - Device according to claim 1 characterized in that the fluid (f) contained in said volumes (V 1) and (V2) may be water, an aqueous mixture or a lubricant.     Device according to Claim 1, characterized in that the circulation of the fluid between said volumes (V 1) and (V 2) can be controlled in particular on its flow rate, and differently according to the direction of flow of said fluid, for example by means of check valve (s) with throttling (D), which can be adjustable or / and controlled by the pressure of the fluid.   6 - Device according to claims 1 and 3 characterized in that the nonelastic flexible membranes (Ml) and (M2) may be coated fabric membranes, for example an elastomeric coated fiberglass cloth.   7 - Device according to claim 3 characterized in that the flexible membrane (M2) elastic may be an elastomeric membranes.   8 - Device according to claim 3 characterized in that the elastic body (G) constraining the flexible membrane (M2), boundary of said volume (V2) may be a spring (s) metal, an elastomeric spring (s), a spring (s) of composite materials, a gas under pressure whose quantity is fixed or adjustable, a deformable element containing a pressurized gas whose quantity is fixed or adjustable exerting on it a fixed or adjustable pressure.   2887000 -8- 9 - Device according to claim 8 characterized in that the pressurized gas whose quantity is fixed or adjustable exerting on said flexible membrane (M2), boundary of said volume (V2) a stress, directly or through a defolmable body containing it, can be air or nitrogen.   - Device according to any one of the preceding claims characterized in that the flexible membranes can be protected, in particular against perforations by covers or bellows (H).