FR3118594A1 - CYCLE SHOCK ABSORBER GUIDE RINGS EXTRACTION TOOL - Google Patents

Abstract

The invention relates to a tool (1) for extracting guide rings (103) from shock absorbers (100), in particular cycle shock absorbers, comprising:- a tubular body (3),- a cylindrical rod (5), located in the tubular body (3), movable in translation relative to the tubular body (3) between two extreme positions, the tubular body (3) comprising at one end at least two arms (7) hinged to said tubular body (3) around tangent axes, regularly distributed over the periphery of the end of the tubular body (3), the cylindrical rod (5) comprising at the end located at the level of the arms (7) of the tubular body (3) a conical tip (11), secured to said cylindrical rod (3) and movable between an insertion position and an extraction position in which the conical tip (11) is relatively close to the end of the tubular body (3) carrying the arms (7) and spreads said arms (7) radially outwards. Figure to be published with abstract: Fig. 2

Description

CYCLE SHOCK ABSORBER GUIDE RINGS EXTRACTION TOOL

The present invention relates to a tool for extracting shock absorber guide rings, in particular fork shock absorbers of cycles such as bicycles.

To improve performance and ride comfort, cycles (bicycles, tricycles, etc.), electrically assisted cycles (“electric bicycles”) and most light motorized cycles are fitted with shock absorbers, particularly at their forks. .

Shock absorbers for cycle forks, in particular for bicycles and bicycles, comprise tubes in which cylinders or rods slide, with a mechanical damping system such as a spring or a pneumatic system which dampens shocks.

These tubes forming the enclosure of the shock absorbers are closed to prevent the infiltration of water and dirt, to guarantee long-term operation.

To improve the guiding of the sliding elements, metal rings, in particular coated with Teflon, can be inserted into the tube. These rings are in particular tubular, thin and adjusted to the dimensions of the tube.

With wear or following excessive shocks, repairs or replacement of shock absorber parts may be required. The guide rings are then notably difficult to extract from the tubes, especially if, following deformation or oxidation, they are glued or clamped against the tube.

Being located in a cramped tube, with a small thickness, said rings are particularly difficult to grasp with rods or hooks.

There is therefore a need for a tool making it possible to easily and effortlessly extract the rings of the shock absorbers, in particular cycle shock absorbers.

In order to at least partially respond to the problem mentioned above, the invention proposes a tool for extracting shock absorber guide rings, in particular cycle dampers, characterized in that it comprises:
- a tubular body,
- a cylindrical rod, located in the tubular body, movable in translation relative to the tubular body between two end positions,
the tubular body comprising at one end at least two arms articulated to said tubular body around tangent axes, regularly distributed over the periphery of the end of the tubular body,
the cylindrical rod comprising at the end located at the level of the arms of the tubular body a conical end piece, integral with said cylindrical rod and movable, by relative translation of the cylindrical rod and of the tubular body between the end positions, between an insertion position in which the conical end piece is relatively far from the end of the tubular body carrying the arms, and an extraction position in which the conical end piece is relatively close to the end of the tubular body carrying the arms and spreads said arms radially outwards.

The extraction tool thus obtained is easy to insert into the tube and the ring. When placed in the open configuration, the hooks at the end of the arms engage the radial edge of the guide ring farthest from the opening, with a power take-off distributed around the circumference of the ring.

The tubular body and the cylindrical rod can be provided for one with a screw pitch for the other with a thread, so that their relative rotation triggers a relative translation of the tubular body and the cylindrical rod.

The cylindrical rod can alternatively slide freely in translation in the tubular body while being fixed in rotation, and the device can comprise a handle, comprising a thread or a screw thread cooperating with respectively a screw thread or a thread arranged on the rod cylindrical, and limiting the sliding of the cylindrical rod relative to the tubular body so that the relative rotation of the handle relative to the cylindrical rod triggers the translation of the cylindrical rod.

The tool may comprise at least three, in particular at least four, articulated arms regularly distributed over the periphery of the end of the cylindrical body.

The arms may include shoulders forming hooks at their free end.

The articulated arms may include teeth or recesses on their radially outer face.

The tool may further comprise an extraction ring disposed around the tubular body and radially prominent, comprising a thread or a thread, and the tubular body then comprises respectively a thread or a thread, so that the rotation of the extraction ring with respect to the tubular body results in a relative translation thereof, said extraction ring forming a stop and power take-off, during use of the tool, against one end of a damper tube.

The articulated arms may include return elements, bringing the articulated arms radially inwards in the absence of stress.

The conical tip can be magnetized or include a magnet and the articulated arms can be ferromagnetic so as to form the return elements.

Other characteristics and advantages will appear on reading the description of the figures below, given by way of illustrative and non-limiting examples of embodiments of the invention, among which:

is a cross-sectional view of part of a cycle fork damper being serviced, in which a tool according to the invention is in use.

is a side view of one embodiment of a tool according to the invention.

is a three-quarter view of the tool from the .

is a sectional view of the tool from the .

is a sectional view of the end of a tool according to the invention being inserted into a ring located in a shock absorber, in the folded state.

is a sectional view of the end of a tool according to the invention being inserted into a ring located in a shock absorber, in the deployed state.

is a side view of the tool in use in a ring-engaging damper tube, shown in section.

Although the description refers in detail to a limited number of embodiments, features of embodiments may be combined to obtain new embodiments, and non-essential features may be modified without departing from the scope of the invention.

There is a schematic representation of a cycle damper 100, shown in section, and in which a ring extraction tool 1 is inserted.

The cycle damper 100 notably comprises tubes 101 in which a damping device (not shown) such as a spring or a pneumatic piston is normally inserted. The damping device normally connects a handlebar or guide element of the cycle and a wheel of the cycle, in order to absorb the shocks received by the wheel.

Following excessive wear or a shock having caused a malfunction, the internal elements of one of the tubes 101 must be replaced. The internal elements comprise, in addition to the damping device, guide rings 103, adjusted to the internal dimensions of the tube 101 containing them. These guide rings 103 must be extracted from the tube containing them 101 using the ring extraction tool 1.

The ring extraction tool 1 is inserted into the tube 101 by one of its ends until it exceeds the ring 103. The extraction tool 1 is shown in more detail in figures 2, 3 and 4.

The ring extraction tool 1 is shown in particular in side view in , three-quarters to and in section .

The ring extraction tool 1 comprises in particular a tubular body 3, forming a guide for a cylindrical rod 5 movable in translation in the tubular body 3. The tubular body 3 and the cylindrical rod 5 comprise for example for one a thread, and for the other a thread, so that a relative rotation of the tubular body 3 with respect to the cylindrical rod causes a translation between them.

The general shape of the tool 1 defines a longitudinal axis A , which corresponds to the axis of the tube of the tubular body 3 and to the directing axis of the cylindrical rod 5. The tool 1 has substantially a symmetry of revolution or any at least one invariance by rotation around said longitudinal axis A .

The tubular body 3 comprises at one end a plurality of arms 7 articulated to said tubular body 3 around tangent axes, regularly distributed over the periphery of the end of the tubular body 3.

In particular, the number of articulated arms 7 is greater than or equal to two, and in particular to three. More particularly, the embodiment of Figures 2 to 4 comprises four arms, distributed in a square on a head 9 carrying the joints located in the extension of the tubular body 3.

The cylindrical rod 5 comprises at the end located at the level of the articulated arms 7 of the tubular body 3 a conical end piece 11, integral with said cylindrical rod 5 and movable, by relative translation of the cylindrical rod 5 and of the tubular body 3 between positions extremes corresponding to extreme positions in relative translation of the cylindrical rod 5 and of the tubular body 3.

The two end positions correspond for one to an insertion position in which the conical endpiece 11 is relatively distant from the end of the tubular body 3 carrying the articulated arms 7, and for the other to an extraction position in which the conical end piece 11 is relatively close to the end of the tubular body 3 carrying the arms 7 and spreads said arms 7 radially outwards.

The conical tip 11 can in particular be made of plastic overmoulded on the cylindrical rod 5.

The arms 7 carry at their free end a hook 13 in the form of a shoulder oriented radially outwards.

In addition to the hooks 13, the arms 7 carry on their radially outer surface recesses 15 or teeth which form power take-offs during the extraction of the ring 103.

For a better grip, the cylindrical rod 5 is integral with a handle 17, for example a star-shaped or circular handle with a peripheral edge having roughness.

According to a particular embodiment, the handle 17 carries the thread or the screw thread cooperating with the screw thread respectively the thread of the cylindrical rod 5. The cylindrical rod 5 then slides freely in translation in the tubular body 3 while being fixed in rotation, and the relative rotation of the handle 17 with respect to the cylindrical rod 5 then triggers the translation of the cylindrical rod 5 between the end positions.

The tool 1 shown in Figures 2 to 4 further comprises an extraction ring 19, surrounding the tubular body 3 and projecting radially outwards from said tubular body 3.

The extraction ring 19 and the tubular body 3 respectively comprise a thread and a thread, so that the relative rotation of the extraction ring 19 with respect to the tubular body 3 triggers its axial translation.

In use, the extraction ring 19 forms a support against the end of the tube and therefore a power take-off for the extraction of the ring 103 (see ).

The various elements of the tool 1 can in particular be machined in metal, for example stainless steel or aluminum.

Figures 5 and 6 illustrate the use of tool 1 to extract a ring 103 from a tube 101.

A portion of a tool 1, in particular around the end carrying the arms 7 and the conical end piece 11 is shown being inserted into a tube 101 of a shock absorber 100 in and after entering the ring 103 in .

In , the conical tip 11 is in the insertion position. The arms 7 are positioned substantially parallel to the longitudinal axis of the tool 1 (axis of the cylindrical rod 5) and the maximum diameter of the tool 1 is consequently reduced, in particular substantially equal to the diameter of the conical tip 11 , and less than the inside diameter of the ring 103.

Tool 1 is then inserted into tube 101 and into ring 103, until arms 7 and in particular hooks 13 pass beyond ring 103.

To hold the arms 7 against the conical end piece 11, said arms 7 may include return elements bringing, in the absence of stress, the arms 7 radially inwards against the conical end piece 11. These return elements may for example be springs, or the conical tip 11 can be magnetized or include an annular magnet so as to cooperate with arms 7 made of ferromagnetic metal.

A user of the tool 1 then turns the handle 17 or the tubular body 3 to bring the conical tip 11 into the extraction position, corresponding to the .

In , the arms 7 are open radially outwards. The diameter of the tool 1 is thereby increased, and is in particular greater than that of the ring 103, with in particular the free end of the arms 7 located against the inner wall of the tube 101.

By pulling on the cylindrical rod 5, the hooks 13 are brought into engagement with the ring 103, so that a traction on the tool 1 is transmitted to the ring 103 to allow its extraction.

The tool 1, with its arms 7 folded or deployed by translation of the conical tip 11 therefore makes it possible to grasp by means of said arms 7 in the deployed state the ring 103 in a tube 101, and thus to exert on said ring 103 important but regularly distributed forces allowing a simplified extraction.

There shows tool 1 more completely and inserted into a tube 101.

In , the tool 1 is in the extraction position, and the arms 7 are engaged with the ring 103 via the recesses 15 instead of the hooks 13 at the end of the arms 7.

The extraction ring 19 is in particular bearing against one end of the tube 103. When the user of the tool 1 turns either the extraction ring 19 or the tubular body 3, the thread pitch between the extraction ring 19 and the tubular body 3 triggers a relative translation of the tubular body 3 with respect to said ring 19.

This translation triggers the extraction of the ring 103, the extraction ring 19 forming a power take-off on the tube 101 by its end.

.The tool 1 according to the invention therefore makes it possible to easily and quickly extract the guide rings 103 in the tubes 101 of the shock absorbers 100. In addition, the regularly distributed arms 7 allow a better distribution of the forces, and damage to the rings 103 and/or tubes 101 can be avoided.

Claims (9)

Tool (1) for extracting guide rings (103) from shock absorbers (100), in particular cycle fork shock absorbers, characterized in that it comprises:
- a tubular body (3),
- a cylindrical rod (5), located in the tubular body (3), movable in translation relative to the tubular body (3) between two end positions
the tubular body (3) comprising at one end at least two arms (7) hinged to said tubular body (3) around tangent axes, regularly distributed over the periphery of the end of the tubular body (3),
the cylindrical rod (5) comprising at the end located at the level of the arms (7) of the tubular body (3) a conical end piece (11), integral with said cylindrical rod (3) and movable, by relative translation of the cylindrical rod (5) and of the tubular body (3) between the end positions, between an insertion position in which the conical tip (11) is relatively far from the end of the tubular body (3) carrying the arms (7), and an extraction position in which the conical end piece (11) is relatively close to the end of the tubular body (3) carrying the arms (7) and spreads said arms (7) radially outwards. Tool according to claim 1, characterized in that the tubular body (3) and the cylindrical rod (5) are provided for one with a screw thread for the other with a thread, so that their relative rotation triggers a relative translation of the tubular body (3) and the cylindrical rod (5). Tool according to Claim 1, characterized in that the cylindrical rod (5) slides freely in translation in the tubular body (3) while being fixed in rotation, in that it comprises a handle (17), comprising an internal thread or a screw thread cooperating with respectively a screw thread or a thread arranged on the cylindrical rod (3), and limiting the sliding of the cylindrical rod (5) relative to the tubular body (5) so that the relative rotation of the handle (17) relative to the cylindrical rod (5) triggers the translation of the cylindrical rod (5). Tool according to Claim 1, 2 or 3, characterized in that it comprises at least three, in particular at least four, articulated arms (7) regularly distributed over the periphery of the end of the cylindrical body (3). Tool according to one of the preceding claims, characterized in that the arms (7) have at their free end shoulders (13) forming hooks. Tool according to one of the preceding claims, characterized in that the articulated arms (7) have teeth or recesses (15) on their radially outer face. Tool according to one of the preceding claims, characterized in that it further comprises an extraction ring (19) arranged around the tubular body (3) and radially projecting, comprising a thread or a thread, and in that that the tubular body (3) respectively comprises a thread or an internal thread, so that the relative rotation of the extraction ring (19) with respect to the tubular body (3) causes a relative translation thereof, said extraction ring (19) forming a stop and power take-off, during use of the tool (1), against one end of a tube (101) of the shock absorber (100). Tool according to one of the preceding claims, characterized in that the articulated arms (7) comprise return elements, bringing the articulated arms (7) radially inwards in the absence of stress. Tool according to the preceding claim, characterized in that the conical end piece (11) is magnetized or comprises a magnet and the articulated arms (7) are ferromagnetic so as to form the return elements.