JP4584471B2 - Anti-lock brake structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an anti-lock brake structure with a reduced manufacturing cost as a simple mechanical structure.
[0002]
[Prior art]
As an anti-lock brake structure that prevents the rotation of a wheel from being locked during braking, for example, Japanese Patent No. 2643946 “Anti-skid brake” is known.
[0003]
In FIGS. 1 and 2 of the above publication, the wheel 1 is rotatably attached to an axle 5 attached to a front fork 8 (the reference numerals used are those described in the publication). A brake disc 2A is attached to the wheel 1 via a clutch 7, and a brake caliper 3A is attached to the front fork 8 in order to brake the brake disc 2A with the brake caliper 3A. In order to brake the brake disc 2B with the brake caliper 3B, the brake caliper 3B is attached to the front fork 8, and the trochoid pump 9 for generating the hydraulic pressure for releasing the clutch 7 is generated inside the wheel 1 and the above. An unloader valve 10 for releasing the hydraulic pressure is arranged, and the wheel is attached to the vehicle body. A rotation sensor 32 for detecting the number of rotations of the vehicle, a vehicle speed sensor 33, and a control for detecting opening and closing of the unloader valve 10 by detecting the slip of the tire based on signals from the rotation sensor 32 and the vehicle speed sensor 33. An anti-skid brake provided with a unit 31 is described.
[0004]
When the brake lever is operated during traveling, the brake disc 2A is braked by the brake caliper 3A, and at the same time, the brake disc 2B is braked by the brake caliper 3B. At this time, when the control unit 31 detects tire slip, the unloader valve 10 is operated, and the clutch 7 is disconnected by the hydraulic pressure from the trochoid pump 9, so that the wheel 1 is not braked by the brake disc 2A. Since braking is performed only by the brake disc 2B, the braking torque for braking the wheel 1 is reduced, and the tire does not slip.
[0005]
[Problems to be solved by the invention]
In the above-described technology, the anti-skid brake is configured as a hydraulic supply device for releasing the connection of the clutch 7 (trochoid pump 9, unloader valve 10, oil passage for supplying hydraulic oil, a seal for preventing leakage of the oil passage, etc. ), A control device (control unit 31) for controlling the hydraulic pressure supply device, and a detection device (rotation sensor 32, vehicle speed sensor 33) for supplying a detection signal to the control device are necessary and expensive. Become. Therefore, for example, it is difficult to employ in a vehicle having a small displacement with reduced manufacturing costs.
[0006]
Therefore, an object of the present invention is to reduce the manufacturing cost by using an anti-lock brake structure as a simple mechanical structure.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a wheel in which an outer wheel on the rim side is fitted to an inner wheel on the axle side so as to be relatively rotatable, and a first friction plate provided on the outer wheel side has an inner wheel side. And a weight for changing the pressing force between the first friction plate and the second friction plate based on the centrifugal force according to the rotational speed of the outer wheel. The transmission torque of the friction clutch is controlled by the number of rotations of the wheel so that the wheel lock phenomenon at the time of braking can be avoided.
[0008]
Since the weight controls the transmission torque of the friction clutch according to the number of rotations of the outer wheel, the wheel speed sensor for performing hydraulic pressure control as in the hydraulic antilock brake structure and the brake pressure are increased or decreased. For this reason, there is no need for a hydraulic unit consisting of a pump, motor, solenoid valve, etc., and a control unit that controls the hydraulic unit in response to a signal from a wheel speed sensor. The wheel lock phenomenon can be avoided.
Therefore, since the manufacturing cost of the antilock brake structure can be reduced, the antilock brake structure of the present invention can be employed in a small motorcycle or the like with reduced costs.
[0009]
A second aspect of the present invention is characterized in that, in the first aspect, a drum brake is provided on the inner wheel, and the drum brake is provided on the inner side in the wheel radial direction of the friction clutch so as to overlap the friction clutch in the width direction. .
[0010]
A drum brake is provided on the inner wheel, and this drum brake is provided on the inner side in the wheel radial direction of the friction clutch so as to overlap the friction clutch in the width direction.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.
FIG. 1 is a side view of a motorcycle having an anti-lock brake structure according to the present invention. The motorcycle 10 includes a body frame 11, a head pipe 12 attached to the front end of the body frame 11, and the head pipe 12 A front fork 13 that is attached to the front fork 13, a front wheel 14 as a wheel attached to the lower portion of the front fork 13, a front fender 15 that covers the front wheel, a handle 16 attached to the upper portion of the front fork 13, and a vehicle body frame 11, a power unit 17 suspended at the rear of the power unit 17, a rear wheel 18 attached to the rear of the power unit 17, an engine 21 constituting the front of the power unit 17, and a cylinder head 22 of the engine 21 connected via an intake pipe 23. Carburetor 24 and a connecting tube to the carburetor 24 5 and air cleaner 26 which is connected via a likewise made of muffler 28. coupled to the cylinder head 22 through an exhaust pipe 27.
[0012]
Here, 32 and 33 are wheels and tires constituting the front wheel 14, 34 is a front cover, 35 is a headlamp, 36 is a front inner cover, 37 is a floor step, 38 is a fuel tank, and 41 and 42 are an engine 21. Head cover and cylinder block, 44 is a seat, 45 is a storage box, 46 and 46 (the rear side 46 is not shown) is a pair of left and right body covers, 47 is a rear cover, 48 is a tail lamp, 51 is a rear fender, 52 is a rear cushion A unit, 53 is a stand, and 54 is a kick pedal.
[0013]
FIG. 2 is a cross-sectional view of the front wheel for explaining the anti-lock brake structure according to the present invention. An axle 61 is attached to each lower end of a pair of left and right forks 13a and 13b constituting the front fork 13, and the axle 61 6 shows a state in which the front wheel 14 is rotatably mounted through bearings 62 and 62 and a drum brake 64 is mounted on the axle 61 through a collar 63. In addition, 61a is a nut screwed into the axle 61, 65 and 65a are collars, and 65c and 65d are seal members.
[0014]
The wheel 32 of the front wheel 14 is rotatably attached to a hub 66 rotatably attached to the axle 61, a spoke 67 integrally extending radially outward from the hub 66, and a bearing (not shown). The rim 68 includes a spoke 67 and a multi-plate friction clutch 70 interposed between the rim 68 and the rim 68.
[0015]
The hub 66 and the spoke 67 constitute an inner wheel 72, and the rim 68 constitutes an outer wheel.
The friction clutch 70 includes a first friction plate 73 (... indicates a plurality, the same applies hereinafter) meshed with the inner peripheral portion of the rim 68, and a second friction plate 70 meshed with the spoke 67. A friction plate 74, a weight 76 that supports the second friction plate 74 at the extreme end and can swing around the support shaft 75 by centrifugal force when the inner wheel 72 rotates, and a first It comprises a pressing plate 78 for pressing the friction plates 73... And the second friction plates 74. 81 is a spacer interposed between the first friction plate 73 and the pressing plate 78 at the end, 82 is a bolt that supports one end of the spring 77 via a washer 83, 84... A seal member 85 that seals between the rim 68 and the rim 68 is a spring support provided on the pressing plate 78 to support the other end of the spring 77.
[0016]
The first friction plate 73 rotates integrally with the rim 68 and is attached to the rim 68 so as to be movable in the direction in which the axle 61 extends.
The second friction plate 74 rotates integrally with the spoke 67 and is attached to the spoke 67 so as to be movable in the direction in which the axle 61 extends.
The weight 76 includes a weight portion 76a having a weight larger than that of other portions and a cam portion 76b having a cam surface gradually separating from the support shaft 75.
[0017]
The drum brake 64 has a base portion 87 attached to the axle 61 and the left fork 13a, a pin 88 attached to the base portion 87, a brake shoe 91 attached to the pin 88 so as to be swingable, and the brake shoe 91 to press the brake shoe 91. And a drum 92 formed in a cylindrical shape on the spoke 67.
[0018]
The operation of the antilock brake structure described above will be described next.
FIGS. 3A and 3B are first operation diagrams for explaining the operation of the antilock brake structure according to the present invention, and the operation of the friction clutch 70 will be described.
In (a), when the motorcycle is stopped, the front wheel does not rotate, so that centrifugal force does not act on the weight 76 and the weight 76 is in a stationary state.
At this time, the first friction plates 73 and the second friction plates 74 are in a state of being pressed through the pressing plate 78 by the elastic force of the spring 77.
[0019]
When the motorcycle starts running and the front wheels start to rotate, the centrifugal force F acts on the weight 76, and the weight 76 starts to swing around the support shaft 75 as shown by the arrow (1) in the figure.
At this time, since the cam portion 76b presses the outermost second friction plate 74 by the swing of the weight 76, the first friction plate 73, the second friction plate 74, the spacer 81 and the pressing plate 78 are pressed. Both move as shown by arrow (2).
[0020]
As a result, the spring 77 is compressed and the elastic force of the spring 77 gradually increases. Accordingly, the pressing force pressing the first friction plate 73 and the second friction plate 74 is increased, and the friction force between the first friction plate 73 and the second friction plate 74 is increased, and the first friction plate 73 and the second friction plate 74 are increased. The transmission torque between the friction plates 74 can be increased.
[0021]
In (b), when the vehicle speed further increases, the rotational speed of the front wheels increases, the centrifugal force F acting on the weight 76 further increases, the swing amount of the weight 76 increases, and the weight portion 76a of the weight 76 is spoken. It hits 67 inner wall 67a. The weight 76 will no longer swing.
[0022]
At this time, the first friction plate 73..., The second friction plate 74..., The spacer 81 and the pressing plate 78 move to the right in the figure, and the first friction plate 73 and the second friction plate. The pressing force of 74 is also maximized, and the maximum friction force is generated between the first friction plate 73 and the second friction plate 74. Accordingly, the transmission torque between the first friction plate 73 and the second friction plate 74 is maximized.
M in the drawing is the maximum movement amount of the pressing plate 78 from the initial state (state (a)) and is also the maximum deflection amount of the spring 77.
[0023]
4 (a) and 4 (b) are second operation diagrams for explaining the operation of the antilock brake structure according to the present invention, (a) is an explanatory view of the front wheels, and (b) is a wheel speed and transmission torque in the front wheels. It is a graph which shows the relationship.
In (a), the wheel speed of the front wheel 14 while the motorcycle is traveling is Vw, and the transmission torque between the outer wheel 68 and the inner wheel 72 is T. Reference numeral 94 denotes a road surface.
[0024]
In (b), the vertical axis represents the transmission torque T between the outer wheel and the inner wheel, and the horizontal axis represents the wheel speed Vw.
When the transmission torque T (in this case, the torque that can be transmitted) when the motorcycle is stopped (wheel speed Vw = 0 (zero)) is T0, the transmission torque T is a straight line as the wheel speed Vw increases from T0. When the wheel speed Vw becomes v1, the transmission torque T becomes the maximum transmission torque T1.
[0025]
At this time, as shown in FIG. 3B, the swing of the weight 76 stops, and therefore, in FIG. 4B, when the wheel speed Vw further increases, the maximum transmission torque T1 is maintained.
[0026]
FIGS. 5 (a) and 5 (b) are third action diagrams for explaining the action of the antilock brake structure according to the present invention. (A) is an explanatory view of the front wheel, and (b) is each speed in the wheel of the front wheel. It is a graph showing the time change of brake force.
In (a), the speed of the axle 61 in which the motorcycle is traveling, that is, the vehicle body speed is V, the speed of the outer wheel 68 is Vwout, and the speed of the inner wheel 72 is Vwin.
[0027]
In this case, the speed Vwout of the outer wheel 68 and the speed Vwin of the inner wheel 72 are speeds calculated by multiplying the rotational speeds per unit time by the outer diameter of the tire 33 when traveling, and the outer wheel 68 and the inner wheel. If there is no relative slip between the tire 72 and the tire 33 and the road surface 94, V = Vwout = Vwin.
[0028]
In (b), the left vertical axis represents speed (body speed V, outer wheel speed Vwout, inner wheel speed Vwin), the right vertical axis represents the brake force B of the drum brake, and the horizontal axis represents time t.
For example, when the front wheel brake is started at time t1 while the motorcycle is running at time t0, and the brake force B is gradually increased, the speed Vwin of the inner wheel provided with the drum brake drum becomes The vehicle body speed V gradually decreases due to the gradual decrease. At this time, the inner wheel and the outer wheel rotate integrally with no relative slip. That is, Vwout = Vwin.
[0029]
From time t2, the torque exceeding the transmission torque T corresponding to the rotational speed of the inner wheel acts on the inner wheel and the outer wheel, and relative slip occurs between the inner wheel and the outer wheel. Speed Vwout exceeds the inner wheel speed Vwin.
Thereby, the slip with respect to the road surface of the tire attached to the outer wheel can be prevented.
[0030]
The braking force B increases more gently than the increase from time t1 to time t2 after the outer wheel has caused relative slip.
After the time t2, the inner wheel speed Vwin rapidly decreases, and Vwin = 0 at time t3.
Further, the outer wheel speed Vwout gradually decreases after time t2, and becomes Vwout = 0 when the vehicle body speed V becomes V = 0 at time t4.
[0031]
As described above with reference to FIGS. 2 and 4B, the present invention includes a wheel 32 in which the outer wheel 68 on the rim side is fitted to the inner wheel 72 on the axle 61 side so as to be relatively rotatable, and the outer wheel. A friction clutch 70 formed by pressing a second friction plate 74 provided on the inner wheel 72 side against a first friction plate 73 provided on the 68 side, and a first friction plate based on a centrifugal force corresponding to the rotational speed of the inner wheel 72 73 and a weight 76 for changing the pressing force between the second friction plate 74 and the transmission torque T of the friction clutch 70 can be controlled by the number of revolutions of the inner wheel 72 to avoid a wheel lock phenomenon during braking. It is characterized by doing so.
[0032]
Since the weight 76 controls the transmission torque T of the friction clutch 70 in accordance with the number of rotations of the inner wheel 72, a wheel speed sensor for performing hydraulic pressure control like a hydraulic type antilock brake structure, and a brake There is no need for a hydraulic unit consisting of a pump, motor, solenoid valve, etc. to increase or decrease the pressure, and a control unit that controls the hydraulic unit in response to a signal from the wheel speed sensor. With the configuration, it is possible to avoid a wheel lock phenomenon during braking.
[0033]
Therefore, since the manufacturing cost of the antilock brake structure can be reduced, the antilock brake structure of the present invention can be employed in a small motorcycle or the like with reduced costs.
[0034]
In addition, although the weight of this invention was provided in the inner wheel in embodiment, you may provide in an outer wheel, not only this. In this case, the pressing force between the first friction plate and the second friction plate is changed based on the centrifugal force acting on the weight according to the rotation speed of the outer wheel. Thereby, the same effect as when the weight is provided on the inner wheel is exhibited.
[0035]
In this embodiment, the weight is of a type that swings due to centrifugal force. However, the weight is not limited to this, and the weight moves linearly outward of the wheel due to centrifugal force or moves away from the axle. It may be in the form of
[0036]
Furthermore, the relationship between the wheel speed Vw and the transmission torque T shown in FIG. 4B is not limited to the proportional relationship as shown in the graph, and the transmission torque T increases in a curve with respect to the wheel speed Vw (the transmission torque T The increase rate of the transmission torque T gradually increases or the increase rate of the transmission torque T gradually decreases).
Furthermore, although the anti-lock brake structure of the present invention is adopted for a wheel braked by a drum brake, it may be adopted for a wheel braked by a disc brake.
[0037]
【The invention's effect】
The present invention exhibits the following effects by the above configuration.
The anti-lock brake structure according to claim 1 is provided on the inner wheel side on a wheel formed by fitting an outer wheel on the rim side so as to be rotatable relative to an inner wheel on the axle side, and on a first friction plate provided on the outer wheel side. A friction clutch that presses the second friction plate, and a weight that changes the pressing force between the first friction plate and the second friction plate based on the centrifugal force according to the rotational speed of the outer wheel. Since the transmission torque of the friction clutch is controlled according to the rotational speed of the outer wheel, a wheel speed sensor for performing hydraulic pressure control like a hydraulic type antilock brake structure, and a pump for increasing or decreasing the brake pressure A hydraulic unit consisting of a motor, solenoid valve, etc., and a control unit that controls the hydraulic unit in response to a signal from a wheel speed sensor Configuration is not required, such as say, it is possible to avoid wheel lock phenomenon at the time of braking by a mechanical simple configuration.
Therefore, since the manufacturing cost of the antilock brake structure can be reduced, the antilock brake structure of the present invention can be employed in a small motorcycle or the like with reduced costs.
[0038]
The anti-lock brake structure according to claim 2 is the anti-lock brake structure according to claim 1, wherein the inner wheel is provided with a drum brake, and the drum brake is provided on the inner side in the wheel radial direction of the friction clutch so as to overlap the friction clutch in the width direction. That is.
[Brief description of the drawings]
FIG. 1 is a side view of a motorcycle equipped with an antilock brake structure according to the present invention. FIG. 2 is a cross-sectional view of a front wheel illustrating the antilock brake structure according to the present invention. FIG. 4 is a second operation diagram illustrating the operation of the antilock brake structure according to the present invention. FIG. 5 is a third operation diagram illustrating the operation of the antilock brake structure according to the present invention. Action diagram [Explanation of symbols]
DESCRIPTION OF SYMBOLS 14 ... Wheel (front wheel), 32 ... Wheel, 61 ... Axle, 68 ... Outer wheel (rim), 70 ... Friction clutch, 72 ... Inner wheel, 73 ... First friction plate, 74 ... Second friction plate, 76 ... Weight , T: Transmission torque.

Claims (2)

A wheel (14) formed by fitting an outer wheel (68) on the rim side so as to be rotatable relative to an inner wheel (72) on the axle (61) side, and a first friction plate provided on the outer wheel (68) side The friction clutch (70) formed by pressing the second friction plate (74) provided on the inner wheel (72) side against (73), and the centrifugal force according to the rotational speed of the outer wheel (68). A weight (76) for changing the pressing force between the first friction plate (73) and the second friction plate (74);
The transmission torque of the friction clutch (70) is controlled by the number of rotations of the outer wheel (68) so that the wheel lock phenomenon during braking can be avoided.
Anti-lock brake structure characterized by that. A drum brake (64) is provided on the inner wheel (14), and the drum brake (64) is provided on the inner side in the wheel radial direction of the friction clutch (70) so as to overlap the friction clutch (70) in the width direction. The antilock brake structure according to claim 1, wherein the antilock brake structure is provided.

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