JP2008195181A - Fork bracket structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To respond to a taste feeling of a two wheeler rider having frequently a pecuriority, by embodying the same appearance as professional specifications using three bolts, when fixedly connecting the upper end side of a front fork to an under bracket. <P>SOLUTION: This fork bracket structure is formed so that right-left gripping parts 11 of the under bracket 1 have an installation hole 11a formed as a split structure for conducting the upper end side of the front fork composed of a car body side tube and a wheel side tube, and the installation hole 11a can be diametrically contracted by fastening of two bolts 2 respectively screwed in the right-left gripping parts 11. An intermediate head 31 formed same as a head part 21 of the two bolts 2, is arranged between the head part 21 in the two bolts 2 of connecting the upper end side of the front fork to the under bracket 1 by diametrically contracting the installation hole 11a by its fastening, by being screwed in the gripping parts 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fork bracket structure, and more particularly to a fork bracket structure suitable for use in mounting a front fork as a hydraulic shock absorber that absorbs road surface vibration input to a front wheel of a traveling motorcycle on the front wheel side of the motorcycle. Regarding improvement.

  There have been various proposals for a fork bracket structure suitable for use in mounting a front fork as a hydraulic shock absorber that absorbs road vibration input to the front wheel of a traveling motorcycle on the front wheel side of the motorcycle.

  Among them, for example, Patent Document 1 discloses that an under bracket that is positioned below an upper bracket and fixedly connects the upper end of the front fork together with the upper bracket uses the plurality of bolts to connect the upper end of the front fork. A fork bracket structure that is fixedly connected is disclosed.

  That is, the under bracket is formed so as to exhibit an arbitrary planar shape that is often a triangle or an oval, and the upper end of the front fork, which is often left and right in many cases, is fixed. In order to connect the two, the left and right end portions are gripping portions, and the gripping portions are formed in a split structure and have attachment holes for conducting the upper end side of the front fork.

  The gripping portion is, for example, a plurality of bolts from the outside, that is, as disclosed in Patent Document 1, the mounting hole formed in the split structure is tightened by screwing two bolts. The diameter is made possible.

  By the way, the front fork is composed of a vehicle body side tube and a wheel side tube, and the vehicle body side tube is formed with a step portion that changes so as to increase the outer diameter, and the grip portion of the under bracket is formed on this step portion. In this state, the gripping portion reduces the diameter of the mounting hole by tightening the bolt.

Therefore, according to the fork bracket structure disclosed in Patent Document 1 described above, the upper end side of the front fork can be fixedly connected to the under bracket by an appropriate tightening operation of the two bolts. .
JP 2004-108431 A (see paragraph 0017, FIG. 1 and FIG. 2 in the specification)

  However, in the proposal disclosed in the above-mentioned Patent Document 1, there is no problem in fixedly connecting the upper end side of the front fork to the under bracket. There may be a small request from the rider.

  In other words, there is an opinion that so-called professional riders such as racers should ensure a more reliable unity when connecting the under bracket and the front fork.

  And from the current situation where it is hoped that a proposal that can realize that will be made, the straightforward measure is to change the number of bolts to be used from two to three. The following are possible problems.

  In other words, when tightening something using bolts, it is easy to tighten two bolts evenly, but it is not easy to tighten three bolts evenly by just adding one bolt. obtain.

  Still, for professional riders and mechanics, evenly tightening the three bolts would be a fateful task, and would be acceptable, but for ordinary riders it would be a bit annoying. It is likely that it will be announced.

  This is because the tightening state using the three bolts mentioned above is a professional specification, so if you are a general rider who has a lot of attention, I would like to propose a method that can easily realize the professional specification Is easily assumed.

  The present invention was devised in view of such a current situation, and the object of the present invention is, of course, that the upper end of the front fork can be fixedly connected to the under bracket. By providing a fork bracket structure that can be adapted to the taste of motorcycle riders who often embrace the same appearance as the professional specifications that use the vehicle, and that is optimal for expecting improved versatility is there.

  In order to achieve the above object, the structure of the fork bracket structure according to the present invention is basically a front fork in which the left and right gripping portions of an under bracket having an arbitrary planar shape are composed of a vehicle body side tube and a wheel side tube. In the fork bracket structure that has a mounting hole formed in a split structure that conducts the upper end side of the screw and that allows the mounting hole to be reduced in diameter by tightening two bolts that are screwed into the left and right gripping parts respectively, It was formed in the same way as the heads of the two bolts between the heads of the two bolts that are screwed into the two bolts and tightened to reduce the diameter of the mounting hole and connect the upper end of the front fork to the under bracket Assume that an intermediate head is provided.

  Therefore, in the present invention, the left and right gripping portions of the under bracket have attachment holes formed in a split structure that conducts the upper end side of the front fork consisting of the vehicle body side tube and the wheel side tube, and Since the mounting hole can be reduced in diameter by tightening the two bolts that are screwed into each part, the upper end of the front fork is fixedly connected to the under bracket by tightening the two bolts as before. It becomes possible to make it.

  In the present invention, since an intermediate head formed in the same manner as the heads of the two bolts is disposed between the heads of the two bolts, a pro that uses three bolts. It can embody the same external appearance as the specification, and can respond to the general rider's hobbies of motorcycles, who often have a lot of attention.

  Hereinafter, the present invention will be described based on the illustrated embodiment. The fork bracket structure according to the present invention has an upper end side of a front fork that is a hydraulic shock absorber that absorbs road surface vibrations input to the front wheels of a traveling two-wheeled vehicle. It is said that it is embodied in an under bracket that connects the two.

  At this time, although not shown, the front fork is formed in a telescope structure having a vehicle body side tube and a wheel side tube so as to be extendable and retractable. It is said that it is formed so that the damping action by expansion and contraction of this damper is made possible.

  Although not shown, the front fork is set to an inverted type in which the vehicle body side tube is a large diameter outer tube and the wheel side tube is a small diameter inner tube, or the large diameter outer tube is a wheel side tube. Of course, the implementation of the present invention is not hindered in any case where the narrow inner tube is set to the upright type in which the vehicle body side tube is used.

  The under bracket 1 shown in FIG. 1 for fixedly connecting the upper end side of the front fork, that is, the upper end side of the vehicle body side tube is not shown, but in many cases, the front bracket is disposed above the front fork as well. It is said that it will be used in an up-and-down pair with an upper bracket that fixedly connects the upper end of the fork.

  Further, in many cases, the under bracket 1 has a so-called pair of left and right front forks. Therefore, the gripping portion that grips the upper end side portion of the front fork at the so-called left and right portions that are the upper and lower portions in FIG. Therefore, as long as the grip portion 11 is provided, it may be formed to have an arbitrary planar shape. However, in many cases, the planar shape is a triangle or an oval shape. It is supposed to be.

  By the way, the fork bracket structure of the present invention is embodied to connect the upper end side of the front fork to the under bracket 1 in a fixed manner. The left and right gripping portions 11 in the bracket 1 have mounting holes 11a formed in a split structure for conducting the upper end side of the front fork, and two bolts 2 respectively screwed into the left and right gripping portions 11 (FIGS. 2 and 2). 3 and FIG. 4), the mounting hole 11a can be reduced in diameter.

  At this time, the two bolts 2 are supposed to be screwed into the gripping portion 11. Specifically, as shown in FIGS. 3 and 4, the split 11 b is formed while the gripping portion 11 is formed. The pair of tightening portions 11c and 11d are screwed into a so-called rear tightening portion 11d which is an upper side in FIG.

  In addition, although not shown, in the pair of tightening portions 11c and 11d, the rear tightening portion 11d is assumed to have a screw thread for screwing the screw thread of the shaft portion of the bolt 2. 1, the front tightening portion 11c, which is the lower side, only penetrates the shaft portion of the bolt 2 and does not have a thread (see FIG. 1).

  Therefore, in this fork bracket structure, the upper end side of the front fork can be fixedly connected to the under bracket 1 by tightening the two bolts 2 as in the conventional case.

  In this fork bracket structure, the head of the two bolts 2 that are screwed into the gripping portion 11 to reduce the diameter of the mounting hole 11a by tightening and connect the upper end side of the front fork to the under bracket 1 is provided. An intermediate head 31 (see FIGS. 2, 3 and 4) formed in the same manner as the head 21 of the bolt 2 is disposed between the portions 21.

  Therefore, this fork bracket structure has the same appearance as a professional specification using a so-called three bolts with a dummy head between two so-called genuine heads 21 (see FIG. 2). It can respond to the general rider's hobby of motorcycles who often have a commitment.

  In other words, this fork bracket structure can achieve the basic purpose of allowing other riders, which are said to be similar, to be recognized as having professional specifications at a glance.

  Then, when a plurality of bolts are screwed into somewhere, it is a common practice to align the so-called heads. Therefore, even in the illustrated embodiment, as shown in FIG. The core of the intermediate head 31 is positioned on the line a connecting the cores of the head 21 of the bolt 2, that is, the heads are aligned, and as indicated by the symbol L in the figure, It is assumed that the intermediate head 31 is positioned in the middle of the head 21 of the two bolts.

  In addition, since the intermediate head 31 is a so-called dummy, it can be said that there is a degree of freedom in the selection of the material, but in order to avoid being recognized as a different thing due to secular change, etc. It would be preferable to form the same material as the bolt 2.

  Further, for disposing the intermediate head 31 at a predetermined position, an arbitrary measure such as so-called sticking may be selected. However, from the viewpoint of realizing a more reliable disposition state, for example, It is preferable that the headed bolt is screwed to the mounting portion 11c (see FIG. 1) of the grip portion 11 as a headed bolt.

  However, even if it is recognized at first glance that the professional specification is applied, if it is found that the intermediate head 31 is only disposed if it is observed carefully, other riders who are regarded as similar to the other side There is also the possibility of being falsified.

  Considering this, it is preferable to take a measure that is not recognized as a so-called dummy. Therefore, the present invention takes the following considerations.

  That is, as shown in FIGS. 3 and 4, the intermediate head 31 is the head of the third bolt 3, and this third bolt 3 is involved in the diameter reduction of the mounting hole 11 a in the grip portion 11. Without being indicated on the grip 11, that is, the crack 11 b in the grip 11, which is screwed into the mounting portion 11 d, the thread of the shaft portion is exposed.

  Therefore, in the places shown in FIG. 3 and FIG. 4, since the shaft portion of the three bolts 2 and 3 is exposed to the crack 11b in the gripping portion 11, other riders regarded as similar to each other can be seen. However, at first glance, it will be recognized that professional specifications are applied, and it will be possible to satisfy the superiority of riders who have a so-called commitment.

  On the other hand, in the present invention, in order to overcome the disadvantage that may be said to be ineffective from the technical point of view, the following consideration is given.

  That is, in the place shown in FIG. 3 and FIG. 4 described above, in order to prevent the third bolt 3 from being easily removed from the arrangement position, this is attached to the gripping portion 11, that is, the rear side. When screwed into the tightening portion 11d, an axial force can be exerted between the tightening portion 11d.

  More specifically, as shown in the enlarged view of FIG. 3, the axial force is caused by the tip 32 of the bolt 3 coming into contact with the so-called bottom of the grind hole 11e remaining in the tightening portion 11d. As shown in FIG. 4, the axial force is generated by the shoulder 33 of the bolt 3 coming into contact with the step portion 11f formed in the tightening portion 11d as shown in FIG. It is going to be done.

  At this time, the third bolt 3 is seated so that the axial force is generated with certainty, that is, in the illustrated manner, the intermediate head 31 is pressed against the outer surface of the grip portion 11. In order to avoid this, a so-called relief is provided by forming a counterbored hole 11g in the tightening portion 11c.

  In view of the above, in the fork bracket structure according to the present invention, as before, the upper end side of the front fork can be fixedly connected to the grip portion 11 in the under bracket 1 by tightening the two bolts 2. Of course, the intermediate head 31 formed in the same manner as the head 21 of the bolt 2 is disposed between the heads 21 of the two bolts 2 so that three bolts are said. It is possible to embody the same external appearance as a professional specification that uses the vehicle, and to respond to the general rider's hobbies of motorcycles that often have a commitment.

  Since the bolt 3 has an axial force with the tightening portion 11d, the bolt 3 is not easily detached from the gripping portion 11, and the third bolt 3 is not known to the rider. In this way, it is possible to avoid in advance the occurrence of a malfunction such as dropping out.

It is a fragmentary top view which shows the holding part of the under bracket which actualized the fork bracket structure by this invention. It is a fragmentary elevation view which shows the state by which the 3rd volt | bolt is arrange | positioned with the two volt | bolts in the holding part of an under bracket. It is a longitudinal cross-sectional view of the holding part shown by the YY line position in FIG. 2, and three bolts. It is a figure which shows other embodiment similarly to FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Under bracket 2, 3 Bolt 11 Grip part 11a Mounting hole 11b Split 11c, 11d Fastening part 21 Head 31 Intermediate head

Claims (4)

The left and right gripping portions of the under bracket having an arbitrary planar shape have mounting holes formed in a split structure that conducts the upper end side of the front fork composed of the vehicle body side tube and the wheel side tube, and are screwed into the left and right gripping portions, respectively. In the fork bracket structure in which the diameter of the mounting hole can be reduced by tightening the two bolts to be inserted, the mounting hole is reduced in diameter by screwing into the gripping part and the upper end side of the front fork is used as the under bracket. A fork bracket structure characterized in that an intermediate head formed in the same manner as the heads of two bolts is disposed between the heads of the two bolts to be connected. The fork bracket structure according to claim 1, wherein the core of the intermediate head is positioned on a line connecting between the cores of the heads of the two bolts. The intermediate head is the head of the third bolt, and the third bolt is screwed into the gripping portion without being involved in the diameter reduction of the mounting hole in the gripping portion, and the shaft portion is screwed into the crack in the gripping portion. The fork bracket structure according to claim 1, wherein the fork bracket is exposed. The shaft portion of the third bolt is screwed into one of the pair of tightening portions that form a crack in the grip portion, and the third bolt is between the other of the pair of tightening portions that form the above-described crack. The fork bracket structure according to claim 3, wherein the fork bracket structure is prevented from loosening.

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