CN2238189Y

CN2238189Y - Back wheel fork for variable speed bicycle

Info

Publication number: CN2238189Y
Application number: CN 95223375
Authority: CN
Inventors: 于秋斌
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-10-23
Filing date: 1995-10-23
Publication date: 1996-10-23
Anticipated expiration: 2005-10-23

Abstract

The utility model relates to a back wheel fork for a variable speed bicycle. Back wheel spokes are symmetrically arranged correspondingly to the central plane of the rotation of wheels, and each back wheel spoke is composed of a back wheel, two V-shaped frames, and a variable speed chain wheel. The end parts of an installation wheel shaft on which the two V-shaped frames of the back wheel is arranged are symmetrically arranged correspondingly to the central plane of the rotation of the wheels, and the distance of the end parts of the V-shaped frame of one side which is provided with the variable speed chain wheel and the central plane of the rotation of the wheels is greater than the distance of the end parts of the V-shaped frame of the other side and the central plane of the rotation of the wheels. The utility model realizes the identical stress of the spokes of both sides of the back wheel, the identical bearing force of the two shafts of the back wheel, equal strength, and equal service life, and extends totally the service life of bicycles.

Description

A kind of rear wheel fork of variable speed bicycle

The utility model relates to a kind of variable speed bicycle, particularly relates to the rear wheel fork structure of variable speed bicycle.

Bicycle is China both urban and rural residents's the main vehicle, along with living standards of the people improve, the vehicle kind of bicycle is developed more many more, have the bicycle (variable speed bicycle, racing car, mountain bike etc.) of accelerating axle to be rapidly developed in recent years, be subjected to deeply the bicycle fan particularly the teenager like.The thicker speed-changing chain of axial dimension is equipped with on the hind axle right side of this bicycle, generally the rear wheel fork with cycle frame is designed to the symmetric shape that the rotating centre plane of relative wheel has equidistance, and the spoke of wheel both sides is taked asymmetric setting, promptly there is the vehicle wheel spoke axle head of speed-changing chain one side (right side, position by bike) nearer apart from the centre plane of wheel, and the vehicle wheel spoke axle head that does not have speed-changing chain one side (left side, position by bike) is far away apart from the centre plane of wheel, the shortcoming of this layout not only makes wheel both sides spoke stressed irregular, and the bearings at both ends that makes rear vehicle shaft is stressed irregular, bearing and vehicle wheel spoke that speed-changing chain one side is housed are stressed bigger, the bearing of opposite side and vehicle wheel spoke are stressed less, this has just caused the not balanced life of Wheel bearing and spoke, and trailing wheel is yielding, from the overall normal non-failure operation time that has reduced bicycle.

The purpose of this utility model is to overcome above-mentioned shortcoming, and a kind of improvement design-calculated variable speed bicycle rear wheel fork is provided, and makes two block bearings of its hind axle stressed near identical, and trailing wheel both sides spoke is stressed near identical, makes it that be arranged identical service life.And trailing wheel car mechanical strength is improved.

Used technical scheme, a kind of variable speed bicycle rear wheel fork of the present utility model is made up of V-arrangement vehicle frame, wheel, speed-changing chain and other universal components, it is characterized in that:

A, the rotating centre plane of rear wheel spoke relative wheel (the left and right symmetrical plane of rotating centre plane of trailing wheel and vehicle frame spider and the rotating centre plane of front-wheel are same planes) is symmetrical arranged;

B, the rotating centre plane of end relative wheel that described V-arrangement vehicle frame is installed wheel shaft is asymmetric setting, the end of V-arrangement vehicle frame that speed-changing chain one side is installed apart from the distance of the rotating centre plane of wheel greater than the V-arrangement vehicle frame end of opposite side distance apart from the rotating centre plane of wheel.

The utility model has following beneficial effect:

1, rear wheel both sides spoke has improved the spoke stress condition for being symmetrical arranged; Under identical material situation, strengthen the formation intensity of wheel;

2, two block bearings of hind axle are stressed near identical, can realize the equal strength of bearing under the situation of using identical bearing, balanced life;

3, rear wheel fork is installed the asymmetrical design of wheel shaft end, manufacture craft and vehicle body external form are had no adverse effects, and functions of use can improve.

Now in conjunction with the accompanying drawings with preferred embodiment

Fig. 1 is the profile scheme drawing of variable speed bicycle.

Fig. 2 is the 2-2 part sectional view of Fig. 1, shows the structure of existing vehicle.

Fig. 3 is the force diagram of two bearing fulcrums of hind axle of the shown existing vehicle of Fig. 2.

The same Fig. 2 in Fig. 4 parting position, the structure of demonstration the utility model revamped design.

Fig. 5 is the force diagram of shown two the bearing fulcrums of the utility model vehicle hind axle of Fig. 4.

Fig. 1 shows the external form scheme drawing of general variable speed bicycle, comprises vehicle frame, wheel, speed-changing chain and other universal components, and improvement of the present utility model only relates to V-arrangement vehicle frame 1 and rear wheel 2; Now only this improvement part is described.

Fig. 2, Fig. 3 show prior art.

V-arrangement vehicle frame 1 comprises horizontal fork arm and the oblique forked lever that links into an integrated entity with it among the figure, easy for narrating, accompanying drawing only is described horizontal fork arm, the oblique forked lever feature is identical does not with it give unnecessary details, the left side of wishbone 1, right horizontal fork arm is installed the end 5 of wheel shaft 7,4 is that the rotating centre plane 6 of relative wheel is symmetrical arranged, a mark hind axle 7 and a left side on the figure, right horizontal fork arm end 5,4 point of connection is respectively a, d, wheel shaft 7 is 0 with the intersection point of the rotating centre plane 6 of wheel, visibility a0=d0 in figure, rear wheel 2 is with left and right sides bearing 8,9 are supported on wheel shaft 7, use symbol b, c marks wheel shaft 7 block bearings 8 respectively, 9 fulcrum, owing on the wheel shaft on wheel 2 right sides speed-changing chain 10 is housed, thereby cause distance b 0＜c0, Fig. 3 to show wheel shaft 7 and bearing 8,9 force diagram, P is the load that puts on hind axle 7 among the figure; Stressed stressed greater than bearing 9 that can judge bearing 8 from this force diagram, and for consideration easy to maintenance, bearing 8,9 uses identical bearing, so it is stressed big bearing 8 to occur, perishable, service life is shorter, bearing 9 is stressed little, and not perishable, service life is longer.Simultaneously because the existence of speed-changing chain 10, and keep the rotating centre plane 6 of wheel to be positioned at the vehicle frame center again, the right left spoke 11,12 that can only make rear wheel 2 is by asymmetric setting, promptly the inclination angle of the spoke 12 on the less and left side, the inclination angle of You Bian spoke 11 is bigger, spoke 11,12 and wheel shaft 7 projection on the ground are scalene, this makes troubles not only for the installation of spoke, and the both sides spoke is stressed inequality, and what caused the both sides spokes does not wait service life yet.

Fig. 4 is the structure of the utility model embodiment, referring to Fig. 4, (installation wheel shaft) end 4 of V-arrangement vehicle frame 1, the rotating centre plane 6 of 5 relative wheels is asymmetric setting, the wishbone end 4 that speed-changing chain 10 promptly is housed is away from described centre plane 6, it is characterized in that wheel shaft 7 and bearing 8,9 fulcrum b, c equates with the distance of the intersection point 0 of axletree 7 with the rotating centre plane 6 of wheel, be b0=c0, this has just realized bearing 8,9 equal stressedly see Fig. 5, the spoke 11 of

same wheel

2,12 have realized being symmetrical arranged, spoke 11,12 with wheel shaft 7 projection on the ground be equicrural triangle, realized the identical stressed and identical service life of both sides spokes.

Because the existence of speed-changing chain 10, so V-arrangement vehicle frame 1 is designed to asymmetric shape, be wishbone 1 and two fulcrum a, d of axletree 7 do not wait apart from the distance of the intersection point 0 of rotating centre plane of wheel and axletree, there is a0＞d0, this asymmetric rear crotch design is not increasing any inconvenience or defective on the technology and on the car body external form, and improved the running condition of bicycle, its substantive distinguishing features and progress are arranged.

Claims

1. the rear wheel fork of a variable speed bicycle is made up of two wishbones, wheel, speed-changing chain, it is characterized in that:

A. the rotating centre plane of rear wheel spoke bearing relative wheel is symmetrical arranged;

B. the rotating centre plane of end relative wheel that described wishbone is installed wheel shaft is asymmetric setting, the wishbone end that speed-changing chain one side is installed apart from the distance of the rotating centre plane of wheel greater than the distance of opposite side wishbone end apart from wheel center of gyration plane.