JPH046598B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a component for making a bicycle with a reverse function.

[Conventional technology]

BACKGROUND OF THE INVENTION Many bicycle drive devices have been invented and put into practical use for forward movement only. The reason for this was that there was no need for bicycles to run afterwards, and it was thought that it was sufficient to only think about moving forward, so there was no need for parts with a reverse function for automobiles.

However, in the PCT application, WO-85/02155-Zach
(Germany) has applied for a similar hub for wheelchairs.

However, since this structure has a ratchet inside the hub shell, it is difficult to obtain the necessary number of ratchets to fit the vehicle, and when attached to a bicycle, it is difficult to eliminate the reaction that bounces back against the pedal. do not have. If an attempt is made to increase the number of engagements, the overall size will become larger and more complex, which is uneconomical, considering the strength. Also, since a large thrust load is applied between parts 42 and 3, it is necessary to constantly supply sufficient oil, but since it is inside, this is not possible, and that part is likely to seize and the reverse rotation becomes heavy. There are some problems that cannot be easily repaired. Also, the second
The explanation of the figures does not take into account the structure of the ratchet function, and this point had to be solved.

Also US Patent 4758013 (TimothyP,
Agrillo) wheelchair reversing hub is available. However, this does not have a brake arm, the pawl 117 is attached to the vehicle body, and the holding part 5 that attaches the hub axle 2 to the vehicle body
If the chain tension is adjusted using the long groove 6, the distance between the ratchet gear 15 and the pawl 117 will change, and in some cases they may come off. Also, since there is only one pawl, the diameter must be increased to increase the number of ratchets in order to reduce the recoil that bounces back when the crank 34 is reversed during forward movement. From the above, the above two examples are suitable for use in wheelchairs, but are not suitable for use in automobiles.

[Problem to be solved by the invention]

A rear hub with a reverse function that can be easily attached to a bicycle, easy to maintain, small, lightweight, and economical at low cost is desirable. Moreover, performance is improving. Unless it is possible to smoothly stop and then go backwards without the reaction of the pedals bouncing back when the pedals are reversed, it cannot be applied to bicycles and cannot be put to practical use.

[Means to solve the problem]

Maintenance is easy if a one-way clutch mechanism is installed between the brake cone and brake arm of a bicycle coaster brake, and it is important to measure both the number of gear teeth and the necessary strength to eliminate the reaction that returns to the pedal. The shape and size are almost the same as conventional coaster brakes.

[Effect]

When the pedals are rotated forward, the vehicle moves forward, when it is stopped, only the wheels rotate freely, and when it is reversed, the brakes are applied until the forward movement stops without reaction to the pedals, and the vehicle stops. If the bicycle is stopped and then reversed again, the bicycle will go backwards, and when the bicycle is stopped, only the wheels will rotate freely. These actions can now be selected arbitrarily.

〔Example〕

FIG. 1 is a partially sectional front view showing a coaster brake according to the present invention, in which a ratchet mechanism, which is a one-way clutch, is provided between a brake arm and a brake cone.

FIG. 2 is a left side view of FIG. 1, with the nut and lock nut tightened on the left main body omitted.

FIG. 3 is a top view of the main part of FIG. 2.

FIG. 4 is an explanatory diagram of the chevron shape of the ratchet gear.

An outline of a conventional coaster brake will be explained with reference to FIG. When the pedal is rotated forward, the forward force is transmitted from the small gear 1 to the drive body 2, and the screw at the tip of the drive body pulls the clutch cone 3 toward the right drive body, and the outer taper of the clutch cone connects to the hub shell 4.
It is pressed against the inner taper of the hub shell 4.
Rotate to move the bicycle forward.

When you stop the pedal, there is no input from the small gear, the connection between the tapered parts separates, and the car rotates freely and coasts. Next, when a reversing force is transmitted to the small gear, the drive body 2 reverses, pushing the clutch cone 3 toward the left brake cone 6, and the outer diameter taper of the clutch cone expands the brake shoe 5 in the radial direction.
When pressed against the inner diameter of the hub shell, the brake shoe attempts to rotate forward due to the sheer force, but the brake shoe is locked to the brake cone, the brake cone is locked to the brake arm, and the brake arm is locked to the vehicle body. Because it is fixed, it cannot rotate, and as a result, the brakes are applied.

In addition, other similar conventional coaster brakes have slightly different internal components, but the braking force is received by a fixed brake cone and brake arm.

Now, Fig. 1 shows a coaster brake with a reverse function by inserting a ratchet between the brake cone and the brake arm of the coaster brake so that the brake cone can only rotate backwards by the action of a one-way clutch. That is, in FIGS. 1 and 2, the conventional female thread of the brake cone 6 is removed, a round hole with different diameters is made, a bearing 20 (integrated with the holding nut 8) is inserted into the large diameter part, and the hub axle 10 is centered. When the brake cone 6 is rotated freely, two oval-shaped surfaces are provided on the part where the brake cone 6 protrudes outward from the hub shell 4 to the left side, and the outer diameter of this convex portion forms a ratchet, and an oval hole is provided in the center. The ratchet gear 11 is inserted in the oval hole into the convex part in a direction in which the pawl is engaged during forward rotation and becomes free during backward rotation, and the gear is locked and connected. The tooth profile of the ratchet gear 11 is a chevron shape in which the apex T of the tooth is drawn backward from the straight line A-A passing through the bottom of the tooth and the center of the ratchet gear 11, as shown in FIG. 4, and the compression applied to the tooth surface. By directing the force toward the inside of the ratchet gear rather than tangentially, this prevents teeth from chipping and increases strength. As a result, small teeth can absorb strong forces, so even if the required number of teeth is determined, a small ratchet gear can be used. Two pawls 12 and 13 are placed on the outside of the outer diameter of the ratchet gear 11, with the pawls sandwiching the ratchet gear, at the positions of pins 15 and 16 that are pivotally attached to the brake arm at the other end of the pawls so that the pawls are shifted half a pitch and engage alternately. Determine the center part of the claw with the claw spring 1
At step 7, pull the two pawls together, make them move simultaneously in a pendulum state, and constantly apply pressure to ensure that they mesh with the gear.When one pawl is pushed up to the mountain of the ratchet gear, it will move by that amount. The other claw is pressed against the ratchet gear so that it engages with the ratchet gear, increasing safety through certainty, and making it impossible to always rotate forwards but allow backward rotations. It is preferable to do this at least 40 times in one rotation, so that even if you reverse the pedal while rolling forward, the reaction from the rebound to the pedal will be within an acceptable range.

Next, brake arm 14 and ratchet gear 1
A flat washer-shaped thrust bearing 19 having a radial, circular, spiral, or a combination of these grease grooves is fitted between the brake cone 6 and the bearing 20. If enough grease is added, reverse rotation will be achieved smoothly.

If you don't install a strong bearing that can retain the grease with a groove or the like, the powerful axial thrust will cause it to seize up quickly and you won't be able to move backwards. Bearings 19 and 20 may be combined into one angular bearing.

Now, if the small gear is reversed and the brakes are applied while the bicycle is moving forward, then the ratchet gear 1
1 tries to rotate in the direction of the arrow, but the claw 12,
Since rotation is stopped by 13, the brake is applied and the bicycle stops. In this case, the moment the small gear is reversed for the first time, there will be a rebound reaction on the pedal, but if the ratchet has more than 40 pawls, it will be enough to be used, but 40 times is not a fixed value. This is a rough guideline; the higher the number, the better. The drawing was drawn 46 times.

Now, when the rotation is further reversed from the stopped state, the ratchet gear rotates in the direction opposite to the arrow, and the pawl 12,
Push up 13 and reverse. This reversal causes the bicycle to move backwards.

〔Effect of the invention〕

In the past, it was thought that a bicycle only needed to be able to move forward, and there was no need for it to be able to go backwards, but by actually creating a hub that could go backwards, it was discovered that the uses of the bicycle could be expanded.

In the case of a multi-wheeled bicycle, it is convenient and comfortable to be able to go forward and backward while riding it, and it is fun to change direction. It can also be used as a utility vehicle.

In an aging society, it is safe and useful for rehabilitation.

Also, by reversing the head angle of the front fork of a two-wheeled vehicle and moving it toward the rear wheel, you can create a two-wheeled bicycle that can go both forward and backward, and when you ride it, you have to move muscles that you didn't move before, which improves your health and promotes exercise. Furthermore, it has become possible to create bicycles that can contribute to humanity.

[Brief explanation of drawings]

FIG. 1 is a partially sectional view showing a coaster brake according to the present invention, in which a ratchet mechanism, which is a one-way clutch, is provided between a brake arm and a brake cone. Figure 2 is a left side view of Figure 1.
The nut and lock nut that are tightened to the left side of the car body are omitted. FIG. 3 is a top view of the main parts of FIG. 2. FIG. 4 is an explanatory diagram of the chevron shape of the ratchet gear. 1... Small gear, 2... Drive body, 3... Clutch cone, 4... Hub shell, 5... Brake shoe, 6... Brake cone, 7... Ball pusher, 8...
...Press nut, 9...Lock nut, 10...Hub axle, 11...Ratchet gear, 12, 13...
...Claw, 14... Brake arm, 15, 16...
Pin, 17... Claw spring, 18... Locking hole, 19...
...Thrust bearing, 20...Bearing.

Claims (1)

[Claims] 1. When the brake cone 6 of a bicycle coaster brake is mounted on the hub axle 10, the shape of the teeth on the part of the brake cone 6 protruding from the hub shell 4 is a straight line A passing through the bottom of the tooth and the center of the ratchet gear.
- The ratchet gear 11, which has a chevron shape with the apex T of the teeth pulled backward from A, is stopped from rotating forward;
The rear rotation is in the free direction, and the ratchet gear 11 is locked and connected, and two pawls 12 are attached to the outer diameter of the ratchet gear 11.
13, the other end of the pawl is pivoted to the brake arm 14 with pins 15 and 16 so that the pawls sandwich the latch gear and engage alternately with a half-pitch shift, and the center part of the pawl is fixed with a pawl spring 17. The two claws are biased toward each other to ensure that the ratchet gear 11
A coaster brake with a reverse function, in which a bearing is inserted between the brake arm 14, the brake cone 6, and the hub axle 10, so that the brake cone 6 cannot rotate forward but can smoothly rotate backward. .