JP2015171842A - Rigidity adjusting bridge for bicycle frame - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bridge that can readily adjust torsional rigidity between two adjacent frame pipes of a bicycle.SOLUTION: A rigidity adjusting bridge 1 for a bicycle frame according to the present invention includes: two plate members 2 and 3 for bridging across two adjacent frame pipes 51 of a bicycle and holding the frame pipes 51 in a sandwich form via a plane defined by the central axes of the frame pipes 51; and fastening components 4 for fastening the two plate members to each other. The torsional rigidity between the two adjacent frame pipes can be adjusted by selecting one of plural plate member pairs each having a different thickness or width or composed of a different material (having a different Young's modulus).

Description

  The present invention relates to a bridge for fixing two adjacent frame pipes of a bicycle, in particular, a pair of pipes extending in parallel, and adjusting torsional rigidity between the two frame pipes.

  Conventionally, between two pipes (for example, between two seat stays or between two chain stays) of the frame constituting the bicycle body, both are reinforced and fixed to prevent twisting. A bridge is provided.

  For example, Patent Document 1 describes an H-shaped integral tubular bridge, which is applied between chain stays or between seat stays, and a separate bridge composed of a tubular bridge and two pairs of pipe grippers. ing. In the integral tubular bridge, the H-shaped portion is fixed to the frame by welding or rivet, and in the separated bridge, the chain stay or the seat stay, the pipe holder and the tubular bridge are all bonded and fixed by an adhesive.

  Patent Document 2 describes a flat bridge that can be applied between both chain stays and between seat stays. The flat bridge is bridged between the chain stays or the seat stays, and both ends of the bridge are welded to portions that come into contact with the chain stays or the seat stays, so that they are fixed between the chain stays or between the seat stays. The

JP-A-62-213078 JP-A-9-193870

  Especially for sports bicycles, adjust the maneuverability and ride comfort according to the driving ability of the driver and the condition of the road to increase the speed when driving on a curve and reduce fatigue due to driving for a long time. There is a need. Moreover, even if it is not for sports, there exists a request among bicycle enthusiasts to adjust maneuverability and riding comfort according to time and circumstances.

  The maneuverability is a performance in which the driver's operation is correctly transmitted to the bicycle, while the force applied to the bicycle (especially the wheels) is correctly transmitted to the driver. Riding comfort is a performance that can properly absorb the force and vibration applied to the bicycle without being excessively transmitted to the driver. Among these, in particular, the steering operation by the driver is correctly transmitted to the front wheels, and the force applied to the front wheels is correctly transmitted to the steering wheel, while the vibration and disturbance applied to the tires such as front wheels and rear wheels are not excessively transmitted to the vehicle body. Desired. There are a front fork, a seat stay, and a chain stay between the wheel and the handle and between the wheel and the vehicle body. The rigidity, particularly the torsional rigidity, has a great influence on the adjustment of the maneuverability and the riding comfort. However, in the conventional bicycles, including those described in Patent Documents 1 and 2, the rigidity cannot be adjusted because they are connected by a bridge fixed by welding or adhesion.

  An object of the present invention is to provide a bridge that can easily adjust the torsional rigidity between two adjacent frame pipes of a bicycle.

In order to solve the above problems, the bicycle frame stiffness adjusting bridge according to the present invention has two frame pipes adjacent to each other with a plane formed by the central axes of the two frame pipes in between. Two plate-like members for sandwiching between both frame pipes,
And a fastener for fastening the two flat plate members together.

  The bicycle frame stiffness adjusting bridge according to the present invention is used as follows. First, two adjacent frame pipes are sandwiched between two flat members. Then, these two flat members are fastened with a fastener such as a screw.

  The torsional rigidity of the two frame pipes is adjusted by adjusting the fastening strength of the two flat plate members by the fastener. In addition, two types of flat plate members with different thicknesses and widths, or materials with different materials (different Young's modulus) are prepared and used by replacing them. The torsional rigidity of the frame pipe can be adjusted.

  As the material of the flat plate member, aluminum or an aluminum alloy, steel (carbon steel, chromium molybdenum steel, stainless steel), magnesium or magnesium alloy, brass, titanium, carbon fiber reinforced resin, or the like can be used.

  A rubber sheet or a resin sheet may be sandwiched between the flat plate member and the two frame pipes. With this configuration, the torsional rigidity of the two frame pipes can be weakened, and vibrations generated in the frame pipes during traveling can be absorbed, thereby contributing to an improvement in riding comfort. In addition, since the vibration of the frame pipe is difficult to be transmitted, the fastener is not easily loosened.

  The two frame pipes may be two chain stays, two seat stays, two fork blades, or a top tube and a down tube.

  According to the bicycle frame stiffness adjusting bridge according to the present invention, the torsional stiffness between two adjacent frames can be adjusted. Moreover, since the replacement is easy, the torsional rigidity can be adjusted with a large width by changing the thickness and material.

1 is an enlarged perspective view showing a state in which a bicycle frame stiffness adjusting bridge according to one embodiment of the present invention is applied between two chain stays. FIG. The perspective view (a), (b) which shows the front and back of the upper flat member of the Example, and the perspective view (c), (d) which shows the front and back of the lower flat member. Sectional view (a) showing a state in which two chain stays are sandwiched between two flat plate members of the same embodiment, and a diagram (b) of a screw for fastening them. The figure for demonstrating the name of each frame pipe of a bicycle. The figure which shows the site | part which can apply the flame | frame frame pipe of a bicycle, and the bridge for frame rigidity adjustments concerning this invention. The expansion perspective view (a) and sectional drawing (b) which show the state which applied the bridge for frame rigidity adjustment of the bicycle which concerns on another Example of this invention to two chain stays and a bottom bracket.

One embodiment of a bicycle frame stiffness adjusting bridge according to the present invention will be described with reference to FIGS.
As shown in FIG. 1, the bicycle frame stiffness adjusting bridge 1 of this embodiment is for sandwiching and fixing two parallel chain stays 51 in a sandwich shape. It consists of a lower flat plate member 3 and six screws 4 for fastening them.

The upper flat plate member 2 and the lower flat plate member 3 are large enough to be bridged between two adjacent chain stays 51 between the bottom bracket 56 and the rear wheel (tire) 6. As shown in the figure, it has a substantially trapezoidal shape in accordance with the spread of the two chain stays 51, and is composed of frame pipe gripping portions 22 and 32 on both sides and plane portions 23 and 33 between them. The
The frame pipe gripping portions 22 and 32 of the upper flat plate member 2 and the lower flat plate member 3 have inner surfaces that are substantially the same as the outer shape of the frame pipe so that the frame pipe (each chain stay 51 in this case) can be held. (Fig. 2 (b) and (d)).
Six screw holes for fastening the upper flat plate member 2 and the lower flat plate member 3 are provided in the flat portions 23 and 33 (FIGS. 2B, 2C and 2D).

  The material of the upper flat plate member 2 and the lower flat plate member 3 is aluminum in the present embodiment, but is not limited to this. For example, reinforced aluminum alloy, steel (carbon steel, chrome molybdenum steel, stainless steel) The same materials as those used for bicycle frames, such as magnesium or magnesium alloy, brass, titanium, carbon fiber reinforced resin, etc. can be used.

  To attach the frame rigidity adjusting bridge 1 of this embodiment, first, the two chain stays 51 are sandwiched between the upper plate member 2 and the lower plate member 3 from above and below, and are lowered into six screw holes. The screw 4 is inserted from the flat member 3 side and screwed with a screwdriver.

  The thickness (the thickness of the upper flat plate member 2 and the lower flat plate member 3) and the width (W in FIG. 2 (d)) of the bridge rigidity adjusting bridge 1 fixed with the two chain stays 51 sandwiched therebetween. By preparing a plurality of sets with different materials or different materials, the torsional rigidity of the two chain stays 51 can be changed (adjusted) in various ways.

  A rubber sheet or a resin sheet may be sandwiched between the upper flat plate member 2 and / or the lower flat plate member 3 and the two chain stays 51. With this configuration, the torsional rigidity of the two chain stays 51 can be weakened. Further, it is possible to absorb vibration from the ground mainly transmitted through the rear wheel 6 during traveling, and to realize a more comfortable riding comfort. Further, since the vibration of the chain stay 51 is difficult to be transmitted, the screw 4 is hardly loosened.

  The frame stiffness adjusting bridge 1 of this embodiment is attached between the two chain stays 51 (A in FIG. 5), but the attachment location is between two adjacent frames of the bicycle, for example, two seats. It may be between the stays 52 (B in FIG. 5), between the two fork blades 53 (C in FIG. 5), and / or between the top tube 55 and the down tube 54 (D in FIG. 5). The torsional rigidity can be adjusted more finely by adjusting the thickness, width, material, attachment location, etc. of the bicycle frame rigidity adjusting bridge 1 according to the present invention.

  Further, since the frame rigidity adjusting bridge 1 of the present invention is replaceable, it has a structure suitable for adjusting the torsional rigidity in accordance with the purpose of using the bicycle. Can also be used for

  A bicycle suitable for mounting the frame rigidity adjusting bridge 1 of the bicycle of the present invention has a thin frame, a road bike having a large maneuverability and mobility by the bridge, and a small-diameter vehicle having a small frame or tire, Needless to say, the single speed is easy to customize, but it can be mounted on other types of bicycles.

  The present invention is not limited to the above embodiment, and can be appropriately modified, added, and modified within the scope of the present invention. For example, the number of screws and the like can be appropriately changed according to the bicycle to be attached and the part. Further, either the upper flat plate member 2 or the lower flat plate member may be located above the frame pipe. Furthermore, the screw hole of the upper flat plate member may pass therethrough, and the upper flat plate member and the lower flat plate member may be connected to each other by a bolt and a nut.

  Moreover, when attaching between the chain stays 51, as shown in FIG. 6, the upper and lower flat plate members 62, 63 may have a shape straddling not only between both the chain stays 51 but also the bottom bracket 56 connecting them. . In this case, the upper and lower flat plate members 62 and 63 may be simply sandwiched by the bottom bracket 56 at a portion extending in front thereof, but may be fixed to the bottom bracket 56 with a screw 64. As a result, the adjustment can be made in the direction of increasing the torsional rigidity.

DESCRIPTION OF SYMBOLS 1 ... Bicycle frame rigidity adjustment bridge 2 ... Upper flat plate member 21 ... Screw hole 22 ... Frame pipe holding part 23 ... Plane part 3 ... Lower flat plate member 31 ... Screw hole 32 ... Frame pipe holding part 33 ... Plane part 4 ... Screw 51 ... Chain stay 52 ... Seat stay 53 ... Fork blade 54 ... Down tube 55 ... Top tube 56 ... Bottom bracket 6 ... Rear wheel (tire)

Claims (4)

Two plate-shaped members for sandwiching two frame pipes adjacent to each other in a sandwich shape across both frame pipes with a surface formed by the center axis of both frame pipes in between,
A bridge for adjusting frame rigidity of a bicycle, comprising: a fastener for fastening the two flat plate members together.   The flat plate member is made of any one of aluminum or aluminum alloy, carbon steel, chromium molybdenum steel, stainless steel, magnesium or magnesium alloy, brass, titanium, or carbon fiber reinforced resin. Bridge rigidity adjustment bridge.   The bicycle frame rigidity adjusting bridge according to claim 1 or 2, further comprising a rubber sheet or a resin sheet interposed between the flat plate member and the two frame pipes.   The two frame pipes are two chain stays, two seat stays, two fork blades, or a top tube and a down tube, respectively. Bicycle frame rigidity adjustment bridge as described.

Images