Bicycle hydraulic device that has a reservoir

Abstract

bicycle hydraulic device (10), which: a container (11) with a first surface (21); a lid (13) with a second surface (22) facing the first surface (21); and a membrane (12) arranged between the container (11) and the lid (13), wherein the membrane (12) has a third surface (23) facing the first surface (21) and a fourth surface (24) facing the second surface (22); characterized by the fact that at least one of the first to fourth surfaces has a convex section (25) extending towards the other surface facing the at least one of the first to fourth surfaces, wherein the membrane (12) is deformed by the container (11) and the lid (13) over the first surface (21) and the second surface (22) and the bicycle hydraulic device (10) further a first fastening component (14) designed for fastening the lid (13) to the container (11) by means of the membrane (12); and a second fastening component (16) designed for fastening the lid (13) to the container (11) by means of the membrane (12), and the first fastening component (14) has a first axis (15), the second fastening component (16) has a second axis (17), and the convex section (25) has an upper section (26) located between the first axis (15) of the first fastening component (14) and the second axis (17) of the second fastening component (16).

Description

[0001] The present invention is directed to a bicycle hydraulic device comprising a reservoir. More specifically, the reservoir comprises a lid and a diaphragm.

[0002] The integration of hydraulic fluid reservoirs into bicycle hydraulic systems has been widely used in recent years. In a bicycle hydraulic system, the movement of a master piston is transmitted to a slave piston. To maintain the position of a physical component, such as a friction component, bicycle hydraulic systems sometimes include a reservoir. Typically, such reservoirs have a volume separated by a flexible diaphragm into two separate chambers: a gas-containing chamber, the gas reservoir, and a fluid-containing chamber, the fluid reservoir. Commonly used reservoir designs include a fluid reservoir with a lid and a diaphragm placed between the fluid reservoir and the lid. Sometimes, the seal between the different components of the reservoirs is unsatisfactory.

[0003] An example of a hydraulic expansion tank is disclosed in DE 10 2007 023 420 A1. The expansion tank comprises a can-shaped container with a circumferential container wall protruding from the bottom, a plastic bellows inserted into the container, which divides the container volume into two separate chambers, and a lid with a circumferential sealing surface for closing the container. The circumferential lid sealing surface forms a sealing gap with a portion of the inside of the container wall, and the bellows has an outer wall with a sealing edge that engages the sealing gap and forms a sealing contact with the inside of the container wall and the sealing surface of the lid.

[0004] Accordingly, the technical object of the present invention is to provide a bicycle hydraulic device having a further improved structure in that the hydraulic fluid is held more stably by improving the seal.

[0005] The problem is solved with a bicycle hydraulic device according to claim 1. Preferred embodiments are described in the dependent claims.

[0006] The bicycle hydraulic device has the features of claim 1.

[0007] In other words, the bicycle hydraulic device consists of a stacked assembly including a reservoir and a lid, and a diaphragm disposed between the reservoir and the lid. At least one of the four surfaces has a convex portion extending toward its corresponding surface. Within the scope of the present invention, the term "diaphragm" refers to an elastic material, such as a diaphragm or the like, that is leak-proof to hydraulic fluid. The purpose of the diaphragm is to compensate for temporary volumetric expansions or contractions of the hydraulic fluid by elastic deformation of the diaphragm. Within the scope of the present invention, the term "convex portion" refers to an increase in the thickness of the corresponding component at a given position at its peripheral edge.However, the term "convex" is not limited to a gradual increase in the thickness of this portion, but covers a wide range of shapes and forms that protrude toward the corresponding surface. If there is no convex portion, two corresponding surfaces are always the same distance apart; the surfaces are practically parallel to each other. By providing this convex portion, the loss in surface pressure along the length of the peripheral edge of the bicycle hydraulic device in the assembled state is compensated for. The latter is based on the observation that, due to the elasticity of the container and the lid, the surface pressure acting on two or more surfaces in contact decreases with increasing distance from the attachment point.Therefore, at a position remote from a mounting point, the local surface pressure can be below the critical surface pressure required to maintain the leak-tightness of the bicycle hydraulic device. According to the invention, the local surface pressure can therefore be locally increased by applying bending stresses to the component in contact with the component having the convex portion. In other words, the surface with the convex portion forces a flat surface to bend along the curvature of the convex portion when the mounting force is thus increased to a sufficient level.

[0008] In view of the above, with all of the four possible first to fourth surfaces in contact with each other, various combinations of convex and non-convex surfaces are possible within the scope of the present invention. It is also possible for all surfaces to have a convex portion. The crucial factor is that, due to the at least one convex portion, the surface pressure along the surfaces is locally increased in the assembled state. Within the scope of the present invention, the term "increased" refers to a reference case in which surfaces are employed that are parallel to each other in the assembled state of the bicycle hydraulic device.

[0009] Preferably, the bicycle hydraulic device further comprises a first fastening component configured for fastening the lid to the container by means of the membrane, and a second fastening component configured for fastening the lid to the container by means of the membrane. Using these two fastening components, the bicycle hydraulic device can be assembled quickly and easily, preferably at two ends of the bicycle hydraulic device. Within the scope of the present invention, the term "fastening component" includes all devices with which the surface pressure on the first to fourth surfaces can be increased when the bicycle hydraulic device is in an assembled state.

[0010] Preferably, the first fastening member has a first axis, the second fastening member has a second axis, and the convex portion has an upper portion located at a portion corresponding to a midpoint of a first virtual line extending between the first axis and the second axis when the lid is attached to the container. In other words, the maximum curvature of the convex portion is located at or near the midpoint between the two fastening members. Generally, when two parallel surfaces are attached to each other by means of two fastening members, the surface pressure is at a minimum in the midpoint between the two fastening members. Therefore, when the upper portion of the convex portion is located at a midpoint of the first virtual line, the local surface pressure at that location can be effectively increased.

[0011] Preferably, the bicycle hydraulic device further comprises a third fastening component configured to fasten the lid to the container by means of the membrane, wherein the third fastening component has a third axis and a second virtual line running between the first axis and the third axis, or a third virtual line running between the second axis and the third axis, is shorter than the first virtual line. The use of a third fastening component has the advantage that more complex contours of the bicycle hydraulic device can be realized, and that the additional fastening component provides additional clamping force at the given location of the bicycle hydraulic device.In a preferred embodiment, the second virtual line and the third virtual line have a length that allows sufficient surface pressure to be maintained along their lengths, even if parallel surfaces are provided along the second and third virtual lines. Here, only the surfaces along the first virtual line have the at least one convex portion according to the invention.

[0012] Preferably, the first to third fastening components are screw bolts, and the reservoir has first to third reservoir screw holes for receiving the first to third fastening components. With screw bolts, the assembly of the bicycle hydraulic device can be easily achieved, and the required clamping force can be readily applied to the cover and the diaphragm.

[0013] Preferably, the lid has first to third lid holes aligned with the respective first to third container screw holes, and the membrane has first to third membrane holes aligned with the respective first to third container screw holes. By means of these first to third lid holes and first to third membrane holes aligned with the first to third container screw holes, a stacking arrangement of the container, membrane, and lid components can be easily achieved before the screws are tightened. Furthermore, even if one or more screws become inadvertently loose, there is no risk of the membrane and / or the lid immediately detaching from the container.

[0014] Preferably, the convex portion is provided on the lid or the container. Alternatively, the convex portion is provided on the lid. Providing the convex portion on the lid or the container, i.e., on one of the structures made of comparatively rigid material, has the advantage that the resulting increase in surface pressure is higher compared to the case where the convex portion is provided on the elastic membrane. Providing the convex portion on the lid has the further advantage that the surface quality of the peripheral edge of the lid may not be as high as the surface quality of the container.

[0015] The lid is preferably made of resin. Resin is a lightweight material with sufficient rigidity, allowing for great flexibility in the design and shape of the lid.

[0016] The diaphragm is preferably made of rubber. Rubber is a cost-effective, durable, and readily available material with sufficient elasticity and chemical resistance to hydraulic fluid.

[0017] The reservoir is preferably made of resin. Resin is a lightweight material with sufficient rigidity, allowing for great flexibility in design and shape, and is chemically resistant to hydraulic fluid.

[0018] Preferably, the reservoir is provided on a base component designed for attachment to a bicycle handlebar. Mounting the reservoir on the handlebar using a base component allows for convenient integration of the reservoir and other hydraulic components on the bicycle handlebar. Furthermore, bleeding the bicycle hydraulic system can be performed more easily if the reservoir is located at a high and easily accessible position.

[0019] Preferably, the base member has a proximal end portion configured for attachment to the bicycle handlebar, a distal end portion, and a grip portion disposed between the proximal end portion and the distal end portion. Furthermore, the bicycle hydraulic device preferably includes a cylinder provided on the base member, a piston disposed in the cylinder, and an actuating member pivotally mounted on the distal end portion for actuating the piston, wherein the actuating member extends downward when the base member is attached to the bicycle handlebar. The present invention is particularly suitable for the bicycle hydraulic device having the described base member and actuating member, since the opening of the reservoir is usually inclined with respect to the horizontal plane.

[0020] Preferably, the bicycle hydraulic device further comprises a switching unit provided on the base member or the operating member. The switching unit is simply provided on the bicycle hydraulic device, which keeps the hydraulic fluid stable.

[0021] Preferably, the bicycle hydraulic device further comprises an elastic cover configured to at least partially cover the base component. The elastic cover improves rider comfort.

[0022] Embodiments of the invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is an exploded side view of the schematically illustrated bicycle hydraulic device according to a first embodiment; Fig. 2 is an exploded side view of the schematically illustrated bicycle hydraulic device according to a second embodiment; Fig. 3 is an exploded side view of the schematically illustrated bicycle hydraulic device according to a third embodiment; Fig. 4 is an exploded side view of the schematically illustrated bicycle hydraulic device according to a fourth embodiment; Fig. 5 is a view of the assembled bicycle hydraulic device according to a first embodiment; Fig. 6 is a view of the assembled bicycle hydraulic device according to a fourth embodiment and Fig. 7 is a cross-sectional view of a basic component comprising a bicycle hydraulic device according to the invention.

[0023] In the description of each of the following embodiments, the same compositional elements have been designated by the same reference numerals, and overlapping descriptions have been omitted. Furthermore, in each drawing, some of the compositional elements have been omitted as necessary for convenience of description.

[0024] The Fig. 1 to 4 show cross-sectional views through a side portion of a bicycle hydraulic device 10 according to the invention, showing different embodiments of the bicycle hydraulic device 10. In these figures, the bicycle hydraulic device 10 is further shown in an exploded view. The bicycle hydraulic device 10 is shown to comprise a reservoir 11, a diaphragm 12, and a lid 13. The diaphragm 12 is positioned between the reservoir 11 and the lid 13. Hydraulic fluid (not shown) is stored in the reservoir 11. The diaphragm 12 extends across the entire horizontal cross-section of the reservoir 11 and separates the bicycle hydraulic device 10 into two chambers: a lower chamber, represented by the reservoir 11 filled with hydraulic fluid, and an upper chamber, represented by a gas volume between the lid 13 and the diaphragm 12. The two chambers are schematically shown in the Fig. 1 to 4 are illustrated by dashed lines, since such technology is generally known to a person skilled in the art. The bicycle hydraulic device 10 has a plurality of fastening components used to mount the cover 13 and the membrane 12 to the container 11. The Fig. 1 to 4 schematically show a first fastening component 14 with a first axis 15 and a second fastening component 16 with a second axis 17.

[0025] In an assembled state of the bicycle hydraulic device 10, the first fastening component 14 and the second fastening component 16 are received in the reservoir 11 through special reservoir screw holes 18, which are provided as threaded holes. In an assembled state of the bicycle hydraulic device 10, the first fastening component 14 and the second fastening component 16 both extend through a diaphragm hole 19 and a cover hole 20, which are provided in the diaphragm 12 and the cover 13 at each attachment point. Each reservoir hole 18, diaphragm hole 19, and cover hole 20, which are arranged one above the other, are aligned one after the other in such a way that the fastening component can extend through the component stack.

[0026] As in the Fig. As shown in Figures 1 to 4, the bicycle hydraulic device 10 has specific surfaces where two adjacent components come into contact with each other when the bicycle hydraulic device 10 is in an assembled state. In this regard, the reservoir 11 has a first surface 21, the lid 13 has a second surface 22, and the diaphragm 12 has a third surface 23 and a fourth surface 24. Here, it is assumed that the first surface 21 is in contact with the third surface 23, and the second surface 22 is in contact with the fourth surface 24.

[0027] In the first embodiment of the invention of Fig. 1 shows that the second surface 22 has a convex portion 25. The second surface 22 is the surface of the cover 13 that, in the assembled state of the bicycle hydraulic device 10, is in contact with the fourth surface 24 of the diaphragm 12. The curvature of the convex portion 25 culminates in an upper portion 26. The upper portion 26 is located between the first axis 15 of the first fastening component 14 and the second axis 17 of the second fastening component 16. In other words, the upper portion 26 is arranged at a portion corresponding to a first virtual line V1 ( Fig. 5) extending between the first axis 15 and the second axis 17 when the lid 13 is attached to the container 11. In the first embodiment, the upper portion 26 is arranged at a portion corresponding to a center portion CP of a first virtual line V1 (see FIG. Fig. 5). According to the first in Fig. 1, the first surface 21, the third surface 23 and the fourth surface 24 are substantially flat and run parallel to one another.

[0028] In the second embodiment of the invention of Fig. 2, it is shown that the third surface 23 has a convex portion 25. The third surface 23 is the surface of the diaphragm 12 which, in the assembled state of the bicycle hydraulic device 10, is in contact with the first surface 21 of the reservoir 11. The curvature of the convex portion 25 culminates in an upper portion 26. The upper portion 26 is located between the first axis 15 of the first fastening component 14 and the second axis 17 of the second fastening component 16. Just as in the first embodiment, the upper portion 26 in the second embodiment is arranged as a portion corresponding to a center portion CP of a first virtual line V1. According to the second in Fig. 2, the first surface 21, the second surface 22 and the fourth surface 24 are substantially flat and run parallel to one another.

[0029] In the third embodiment of the invention of Fig. 3 shows that the fourth surface 24 has a convex portion 25. The fourth surface 24 is the surface of the diaphragm 12 which, in the assembled state of the bicycle hydraulic device 10, is in contact with the second surface 22 of the cover 13. The curvature of the convex portion 25 culminates in an upper portion 26. The upper portion 26 is located between the first axis 15 of the first fastening component 14 and the second axis 17 of the second fastening component 16. Just as in the first embodiment, the upper portion 26 in the third embodiment is arranged as a portion corresponding to a center portion CP of a first virtual line V1. According to the third in Fig. In the embodiment shown in Figure 3, the first surface 21, the second surface 22 and the third surface 23 are substantially flat and run parallel to one another.

[0030] In the fourth embodiment of the invention of Fig. 4 further shows that the first surface 21 has a convex portion 25. The first surface 21 is the surface of the reservoir 11 that, in the assembled state of the bicycle hydraulic device 10, is in contact with the third surface 23 of the diaphragm 12. The curvature of the convex portion 25 culminates in an upper portion 26. The upper portion 26 is located between the first axis 15 of the first fastening component 14 and the second axis 17 of the second fastening component 16. Just as in the first embodiment, the upper portion 26 in the fourth embodiment is arranged as a portion corresponding to a center portion CP of a first virtual line V1. According to the fourth in Fig. 4, the first surface 21, the second surface 22 and the fourth surface 24 are substantially flat and parallel to one another.

[0031] The diaphragm 12 is made of an elastic material, such as rubber or the like, and is compressed by both the lid 13 and the reservoir 11 via the first surface 21 and the second surface 22 when force is applied to the bicycle hydraulic device 10. Compression of the stack consisting of the reservoir 11, the diaphragm 12, and the lid 13 must be achieved so that a stable sealing function is achieved between the third surface 23 and the fourth surface 24. To achieve a reliable seal, the surface pressure between the first fastening component 14 and the second fastening component 16 must be sufficiently high, as described in more detail below.

[0032] The Fig. 5 and Fig. 6 illustrate the bicycle hydraulic device 10 in an assembled state, wherein Fig. 5 illustrates the bicycle hydraulic device 10 according to the first embodiment of the invention and Fig. 6 illustrates the bicycle hydraulic device 10 according to the fourth embodiment of the invention. The bicycle hydraulic device 10 is mounted by a total of three fastening components 14, 16 and 27. In the embodiments shown, Fig. 5 and Fig. 6, the distance between the first fastening component 14 and the second fastening component 16 is greater than the distance between the first fastening component 14 and the third fastening component 27. Also, the distance between the second fastening component 16 and the third fastening component 27 is shorter than the distance between the first fastening component 14 and the second fastening component 16. In other words, a second virtual line V2 running between the first axis 15 and the third axis 28, or a third virtual line V3 running between the second axis 17 and the third axis 28, is shorter than the first virtual line V1.

[0033] From a force-flow perspective, two effects must be considered when analyzing the surface pressure along the length between the first fastening component 14 and the second fastening component 16 (and, if applicable, between the first fastening component 14 or the second fastening component 16 and the third fastening component 27).

[0034] First, the surface pressure exerted on the stack consisting of the container 11, the lid 13, and the membrane 12 by the first fastening member 14 and the second fastening member 16 gradually decreases with increasing distance from each of the fastening members, depending on the elasticity of the materials of the container 11 and the lid 13. Therefore, according to this first aspect alone, the surface pressure is minimal at the mid-length between the first fastening member 14 and the second fastening member 16. Consequently, the surface pressure may differ along the length of the first fastening member 14 and the second fastening member 16, so that reliable sealing cannot be guaranteed.

[0035] Next, the surface pressure exerted on the lid 13 and the diaphragm 12 by the convex portion 25 of the lid 13 depends on the curvature of the convex portion 25. More specifically, the smaller the gap between the first surface 21 and the fourth surface 24, the higher the surface pressure acting on the diaphragm 12, assuming infinite rigidity of the container 11 and the lid 13. Therefore, according to this second aspect alone, the surface pressure acting on the diaphragm 12 is at a maximum where the curvature of the convex portion 25 reaches its maximum at the upper portion 26.

[0036] Since the material of the container 11 and the lid 13 is elastic to a certain extent, both of the aspects identified above must be taken into account in order to maintain a surface pressure above the critical surface pressure along the entire distance between the first fastening component 14 and the second fastening component 16. The latter is achieved with the bicycle hydraulic device 10 according to the invention. Here, the curvature of the convex portion 25 is designed to compensate for the decrease in surface pressure exerted by the fastening components, particularly in the middle of the length between the first fastening component 14 and the second fastening component 16.

[0037] The convex portion 25 may be provided only on the long side of the bicycle hydraulic device 10, between the first fastening member 14 and the second fastening member 16. In the embodiments shown, the two other sides of the bicycle hydraulic device 10 are short enough to provide a surface pressure sufficient to maintain the critical surface pressure. It is shown that the convex portion 25 of the cover 13 causes the diaphragm 12, which is arranged under the cover 13, to deform according to the curvature of the convex portion 25 of the cover 13. It is also shown that in the center, at the upper portion 26 of the convex portion 25, the gap between the reservoir 11 and the cover 13 is minimal. Of course, a convex portion 25 may also be provided on one or both of the other two sides of the bicycle hydraulic device 10.

[0038] Fig. 7 schematically illustrates the bicycle hydraulic device 10 attached to the bicycle. Here, the bicycle hydraulic device 10 is incorporated into a base member 29 of a bicycle brake device having an electric switching unit 38 for electrically actuating a derailleur. The bicycle hydraulic device is mounted on the handlebar 30 by means of the base member 29. The base member 29 has a proximal end portion 31 and a distal end portion 32. A grip portion 33 is provided between the proximal end portion 31 and the distal end portion 32. Furthermore, a cylinder 34 is provided on the base member 29, and a piston 35 is arranged in this cylinder 34. The piston 35 can be actuated by means of an actuating member 36. The actuating member 36 is a brake lever that is pivotally attached to the distal end portion 32 of the base member 29.Here, the actuating member 36 is attached to the distal end portion 32 of the base member 29 such that the actuating member 36 extends downward when the base member 29 is attached to the bicycle clamp.

[0039] As shown, the base member 29 further includes an elastic cover 37, shown in dashed lines, covering the handlebar portion 33. While riding the bicycle, the rider's hands can rest on the elastic cover 37, thereby increasing user comfort.

[0040] Although the Fig. 7 is an electrical switching unit, the present invention could also be applied to a mechanically actuated switching unit which is designed for actuation by means of a switching cable of a Bowden cable. REFERENCE SYMBOL 10 Bicycle hydraulic device 11 containers 12 Membran 13 lids 14 first fastening component 15 first axis 16 second fastening component 17 second axis 18 Container screw hole 19 membrane hole 20 lid hole 21 first area 22 second area 23 third area 24 fourth area 25 convex section 26 upper section 27 third fastening component 28 third axis 29 Basic component 30 bicycle handlebars 31 proximal end section 32 distal end section 33 Handle section 34 cylinders 35 pistons 36 Actuating component 37 elastic cover 38 switching unit V1 first virtual line V2 second virtual line V3 third virtual line CP middle section

Claims

[1] Bicycle hydraulic device (10) which: a container (11) having a first surface (21); a cover (13) having a second surface (22) facing the first surface (21); and a membrane (12) arranged between the container (11) and the lid (13), the membrane (12) having a third surface (23) facing the first surface (21) and a fourth surface (24) facing the second surface (22); characterized by , that at least one of the first to fourth surfaces has a convex portion (25) extending toward the other surface facing the at least one of the first to fourth surfaces, wherein the membrane (12) is deformed by the container (11) and the lid (13) over the first surface (21) and the second surface (22), and the bicycle hydraulic device (10) further a first fastening component (14) designed to fasten the lid (13) to the container (11) by means of the membrane (12); and a second fastening component (16) which is designed for fastening the lid (13) to the container (11) by means of the membrane (12), and the first fastening component (14) has a first axis (15), the second fastening component (16) has a second axis (17), and the convex portion (25) has an upper portion (26) located between the first axis (15) of the first fastening component (14) and the second axis (17) of the second fastening component (16). [2] The bicycle hydraulic device (10) according to claim 1, wherein the upper portion (26) is disposed at a portion corresponding to a center portion (CP) of a first virtual line (V1) extending between the first axis (15) and the second axis (17) when the lid (13) is attached to the container (11). [3] Bicycle hydraulic device (10) according to claim 2, further comprising: a third fastening component (27) which is designed for fastening the lid (13) to the container (11) by means of the membrane (12); wherein the third fastening component (27) has a third axis (28) and a second virtual line (V2) running between the first axis (15) and the third axis (28) or a third virtual line (V3) running between the second axis (17) and the third axis (28) is shorter than the first virtual line (V1). [4] A bicycle hydraulic device (10) according to claim 3, wherein the first to third fastening components are screw bolts and the reservoir (11) has first to third reservoir screw holes (18) for receiving the first to third fastening components. [5] Bicycle hydraulic device (10) according to claim 4, wherein the lid (13) has first to third lid holes (20) aligned with the respective first to third container screw holes (18), and the membrane (12) has first to third membrane holes (19) aligned with the respective first to third container screw holes (18). [6] Bicycle hydraulic device (10) according to one of the preceding claims, wherein the convex portion (25) is provided on the lid (13) or the container (11). [7] Bicycle hydraulic device (10) according to claim 6, wherein the convex portion (25) is provided on the cover (13). [8] Bicycle hydraulic device (10) according to one of the preceding claims, wherein the cover (13) is made of resin. [9] Bicycle hydraulic device (10) according to one of the preceding claims, wherein the membrane (12) is made of rubber. [10] Bicycle hydraulic device (10) according to one of the preceding claims, wherein the container (11) is made of resin. [11] Bicycle hydraulic device (10) according to one of the preceding claims, wherein the container (11) is provided on a base component (29) which is designed for attachment to a bicycle handlebar (30). [12] Bicycle hydraulic device (10) according to claim 11, wherein the base member (29) has a proximal end portion (31) adapted for attachment to the bicycle handlebar (30), a distal end portion (32) and a grip portion (33) disposed between the proximal end portion (31) and the distal end portion (32). [13] Bicycle hydraulic device (10) according to claim 12, further comprising: a cylinder (34) provided on the base member (29); a piston (35) arranged in the cylinder (34); and an actuating member (36) rotatably attached to the distal end portion (32) for actuating the piston (35), the actuating member (36) extending downward when the base member (29) is attached to the bicycle handlebar (30). [14] Bicycle hydraulic device (10) according to claim 13, further comprising: a switching unit (38) which is provided on the base component or the actuating component. [15] Bicycle hydraulic device (10) according to one of the preceding claims 11 to 14, further comprising: an elastic cover (37) which is designed to at least partially cover the base component (29).

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