JP2005199927A - Bicycle tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bicycle tire having excellent traveling property, steering property, braking performance, cornering performance, durability and mud-removing property without canceling the performances with each other. <P>SOLUTION: In the bicycle tire 1 in which a plurality of knobs 2 are arranged on a tread surface 10, each knob 2 comprises a base part 4 of trapezoidal section protruded from the tread surface 10, and a columnar block part 3 continuous to a top face of the base part 4. The block part 3 and the base part 4 overlap so that peripheral wall surfaces 30 and 40 thereof overlap each other. The riser angle θ1 of the peripheral wall surface 30 of the block part 3 with respect to the tread surface 10 is set to be larger than the riser angle θ2 of the peripheral wall surface 40 of the base part 4 and ≤ 90°. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a bicycle tire. In particular, the present invention relates to a bicycle tire in which a plurality of knobs are arranged on a tread surface of a tire in order to travel on off-road such as wasteland, muddy ground, and sand.

  As shown in Fig. 7, the bicycle tires used in mountain bikes, etc., can be used to ensure safe and good driving even in harsh road conditions such as wasteland and muddy ground. A plurality of block-shaped knobs 2 are arranged on the tread surface 10 that comes into contact with each other. Depending on the shape and arrangement pattern of the knob 2, the running performance, maneuverability, brake performance, durability, mud-penetration, etc. will change. Bicycle tires 1 with different patterns are designed.

  In such a bicycle tire 1, the knob 2 protrudes from the tread surface 10. Therefore, when the bicycle is driven, the knob 2 is in a direction opposite to the traveling direction, as indicated by a broken line in FIG. 8. Since the rolling resistance is generated due to the deformation, the driving force is not efficiently transmitted to the road surface, and there is a problem that the traveling performance and the maneuverability are deteriorated. Therefore, by increasing the size of the knob 2, the contact area between the road surface and the top surface 21 of the knob 2 is increased to increase the transmission of the driving force, and the deformation of the knob 2 is suppressed to a small level, so that the bicycle can run. , To improve maneuverability.

  Further, the knob 2 protruding from the tread surface 10 is likely to be worn or damaged by friction or load applied during breaking or cornering, and there is a problem that the braking performance and cornering performance are deteriorated. Therefore, as shown in FIG. 8, the peripheral wall surface 20 of the knob 2 is formed in a tapered shape that expands toward the tread surface 10, thereby reducing wear and breakage of the knob 2 and improving durability. We are trying to improve.

Further, when traveling in a muddy area, if the groove G formed between the knobs 2 is clogged with mud, the weight of the bicycle tire increases by the amount of the mud and the road surface is firmly captured by the knob 2. Inability to travel, poor running performance and maneuverability, and is prone to slipping. Therefore, the knob 2 is formed in a spike shape, or, as shown in FIG. 8, a curved portion R is formed at the connecting portion between the knob 2 and the tread surface 10 to the groove portion G between the knobs 2. By adopting a configuration that can suppress mud adhesion and efficiently discharge clogged mud, the mud removal performance is improved.
JP-A-5-162510 No. 7-28004

However, the configuration of the knob 2 that improves each performance described above is contradictory.
Specifically, when the size of the knob 2 is increased in order to improve traveling performance and maneuverability, the groove portion G between the knobs 2 becomes narrower and the mud-repelling property is deteriorated, and the bicycle tire 1 is deteriorated. Weight also increases. For the sake of durability, when the rising angle θ4 of the knob 2 from the tread surface 10 is decreased to increase the taper amount of the peripheral wall surface 20, the area of the top surface 21 of the knob 2 that contacts the road surface decreases. As a result, the transmission efficiency of the driving force is lowered, so that the running performance and the handling performance are deteriorated, and the braking performance and cornering performance are also lowered due to the reduction of the frictional force. If the knob 2 is formed in a spike shape to improve the mud-repelling property, the travel performance and the maneuverability are deteriorated due to the reduction of the contact area between the knob 2 and the road surface, and the strength of the knob 2 is reduced. As a result, it is easily worn or damaged, and the durability is also lowered.

In this way, combining the above-mentioned configurations that improve each function, it is possible to design a bicycle tire that excels in all aspects of running performance, maneuverability, braking performance, cornering performance, durability, and mud repellency. Impossible.
Therefore, in designing the actual bicycle tire 1, the shape and arrangement pattern of the knob 2 are determined in consideration of the use of each bicycle and the running conditions such as the road surface, giving priority to the improvement of performance that should be particularly emphasized. doing.

  The present invention has been made in view of the above circumstances, and in the “bicycle tire in which a plurality of knobs are arranged on the tread surface”, as described above, the respective performances are not offset from each other. It is an object to provide a bicycle tire that is excellent in all of performance, braking performance, cornering performance, durability, and mud repellency.

(1) The bicycle tire of the invention according to claim 1 is: “The knob has a trapezoidal cross-sectional base portion protruding from the tread surface and a columnar shape connected to the top surface of the base portion. It consists of a block part,
The block portion and the base portion are overlapped so that their peripheral wall surfaces are continuous, and the rising angle of the peripheral wall surface of the block portion with respect to the tread surface is the rising angle of the peripheral wall surface of the base portion Greater than and less than or equal to 90 degrees ”.
According to this, the knob 2 has a two-stage structure in which the base portion 4 having a small rising angle θ1 from the tread surface 10 and the block portion 3 having a large rising angle θ2 overlap each other. The height M of the columnar block portion 3 that contacts the road surface and receives a force in the direction opposite to the traveling direction can be reduced, and deformation of the block portion 3 is suppressed because it is supported by the base portion 4. Similarly, deformation of the knob 2 in the advancing direction is suppressed by the base portion 4 during braking and cornering. Therefore, rolling resistance caused by deformation of the knob 2 is reduced, and wear and breakage of the knob 2 are prevented.

  The angle formed by the tread surface 10 and the peripheral wall surface 40 of the base portion 4 and the angle formed by the peripheral wall surface 40 of the base portion 4 and the peripheral wall surface 30 of the block portion 3 are both obtuse angles. Since the width of the groove portion G formed between the knobs 2 increases from the tread surface 10 toward the tip of the knob 2, the groove portion G is not easily clogged with mud and the clogged mud is It is discharged smoothly due to deformation of the knob 2 or the like.

(2) The bicycle tire of the invention according to claim 2 is: “The center of the top surface of the base portion connected to the block portion is rearward of the traveling direction of the bicycle tire from the center of the bottom surface”. It is characterized by being 'positioned'.
According to this, the taper amount of the peripheral wall surface 40a located in the forward direction of the base portion 4 is large, and the angle formed by the tread surface 10 and the peripheral wall surface 40a of the base portion 4 is also large. The mud hardly adheres to the connecting portion C between the tread surface 10 and the base portion 4 and is easily removed even if it adheres.

(3) The bicycle tire of the invention according to claim 3 is characterized in that "the block portion occupies a height of one-third to two-thirds of the height of the entire knob".
According to this, since the road surface can be surely captured by the knob 2, the driving force can be efficiently transmitted to the road surface, and the amount of deformation of the knob 2 can be kept small, so that the rolling resistance is reduced.

(4) The bicycle tire of the invention according to claim 4 is characterized in that "the block portion is a prismatic shape and a plane constituting the peripheral wall surface is arranged in a traveling direction of the bicycle tire". To do.
According to this, since the load applied to the knob 2 at the time of traveling or braking can be received by the entire flat surfaces 31a and 31b constituting the peripheral wall surface 30, the base portion 4 and the block portion 3 are Hard to tear.

(5) The bicycle tire of the invention according to claim 5 is characterized in that “the block portion has a tapered shape that expands toward a connecting portion with the base portion”.
According to this, the angle formed by the peripheral wall surface 40 of the base part 4 and the peripheral wall surface 30 of the block part 3 is larger than that when the rising angle θ2 of the block part 3 is 90 degrees, and the base The rising angle θ1 of the portion 4 is reduced. Thereby, since the taper of the whole knob becomes larger than that of the rising angle θ2 of 90 degrees, mud is not easily clogged in the groove portion G between the knobs 2 and clogged mud is easily discharged. Further, since the deformation of the block portion 3 is suppressed to a small level, it is difficult to be worn or damaged.

(6) The bicycle tire of the invention according to claim 6 is characterized in that “the base portion is a truncated cone”. According to this, even when a load is applied to the knob 2 from any direction, the block portion 3 can be similarly supported by the truncated cone.

(7) The bicycle tire of the invention according to claim 7 is characterized in that “the base portion is a truncated pyramid”. According to this, by arranging the knob 2 so that the planes 41 a to 41 d constituting the truncated pyramid face in a predetermined direction, a load is applied by a straight line that is a connecting portion C of the base portion 4 and the block portion 3. Since it can be received and supported, the strength of the knob 2 in a specific direction can be improved.

  As described above, according to the first aspect of the present invention, the knob 2 has the two-stage knob 2 in which the columnar block part 3 is connected to the base part 4 having a trapezoidal cross section protruding from the tread surface 10. As a result, the deformation of the block portion 3 with respect to the traveling direction of the bicycle tire 1 can be kept small without increasing the size of the knob 2 or reducing the height M of the knob. The increase in weight of the tire 1 can be reduced. Therefore, it is excellent in running performance and maneuverability.

Even during braking and cornering, the peripheral wall surface 40 of the base portion 4 supports the block portion 3, so that the wear of the knob 2 can be reduced without reducing the contact area between the block portion 3 and the road surface. Breakage can be prevented. Therefore, the brake performance, cornering performance, and durability are excellent.
Further, the angles formed by the tread surface 10 and the peripheral wall surface 40 of the base part 4, the peripheral wall part 40 and the peripheral wall surface 30 of the block part 3 are both obtuse, and the groove part G between the knobs 2 is Since it expands toward the tip of the knob 2, mud clogging can be prevented and clogged mud can be discharged smoothly without forming the knob 2 in a spike shape. Therefore, the mud repellency is excellent.
From these, in the bicycle tire of the configuration of the present invention, the running performance, the handling performance, the braking performance, the cornering performance, the durability, and the mud repellency performance are not offset each other, and all the performances are excellent. Bicycle tires can be designed.

According to the invention which concerns on Claim 2, the center A of the top surface of the base part 4 was located back with respect to the advancing direction rather than the center B of the bottom face, so that the tread surface 10 and the base part 4 Since the mud hardly adheres to the connecting portion and is easily removed even if it adheres, the mud-repelling property is excellent.
According to the third aspect of the present invention, since the height M of the block portion 3 is set to one third to two thirds of the height H of the knob, the driving force can be efficiently transmitted and the rolling resistance is increased. Therefore, it is excellent in running and maneuverability.

According to the invention according to claim 4, by arranging the plane of the prismatic block portion 3 with respect to the traveling direction of the bicycle tire 1, the base portion 4 and the base portion 4 are caused by a load during traveling or braking. Since the block portion 3 is not easily torn, it has excellent durability.
According to the invention which concerns on Claim 5, since it was set as the taper-shaped block part 3, since it is hard to clog mud in the groove part G between the knobs 2 and clogged mud is easy to be discharged, mud drainage is excellent. Yes. Moreover, since the said block part 3 is hard to be worn out or damaged, durability is also excellent.

According to the invention which concerns on Claim 6, since the said base part 4 was made into the truncated cone, when the load is applied to the knob 2 from which direction, the said block part 3 can be supported, Therefore Durability is excellent. .
According to the invention which concerns on Claim 7, since the intensity | strength of the said knob 2 can be improved with respect to the load from a specific direction by making the base part 4 into the truncated pyramid, durability is excellent.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
<Embodiment 1>
A bicycle tire 1 according to an embodiment of the present invention is shown in FIGS. 1 and 2.
As shown in FIG. 1, this includes a base part 4 having a trapezoidal cross section projecting from a tread surface 10, and a columnar block part 3 connected to the base part 4 and contacting a road surface during driving. Is a bicycle tire 1 corresponding to off-road driving in which a knob 2 having a two-stage structure is arranged along a circumferential direction, and the base portion 4 and the block portion 3 are peripheral wall surfaces having different inclination angles. 40 and 30 are formed so as to be continuous via the connecting portion C.

  The base part 4 is an elliptical frustum having a major axis in the traveling direction of the bicycle tire 1, and as shown in FIG. 3, the center B of the top surface is a rear position in the traveling direction with respect to the center A of the bottom surface. It is formed to become. Therefore, the peripheral wall surface 40a located in the front in the traveling direction has a smaller rising angle θ1 from the tread surface 10 and a taper amount than the rear and left and right peripheral wall surfaces 40b. Further, the rear and left and right peripheral wall surfaces 40b are formed to have the same rising angle θ3.

  The block portion 3 is a square frustum having a square cross section, and is connected to the top surface of the base portion 4 as shown in FIG. The peripheral wall surface 30 of the block portion 3 has a tapered shape that expands toward the tread surface 10 and has a rising angle θ2 close to a right angle. The block 3 is arranged such that the planes 31 a and 31 b constituting the peripheral wall surface 30 are parallel to the traveling direction so that the planes 31 a and 31 b are parallel to the traveling direction of the bicycle tire 1. .

  In this example, the knob 2 is formed with rising angles θ1: 30 degrees and θ2: 80 degrees of the peripheral wall surface 40 of the base portion 4 and rising angles θ3: 45 degrees of the rear peripheral wall surface. Further, the height N of the base portion 4 and the height M of the block portion 3 are formed to be 3/5 and 2/5 the height H of the knob.

  Since the bicycle tire of this example is configured as described above, the block portion 3 having a rising angle θ2 close to a right angle can firmly capture road surfaces such as wasteland and muddy ground where the bicycle travels, Since the block portion 3 is less than half of the height H of the knob 2, deformation of the knob 2 in the traveling direction of the block portion 3 and the opposite direction can be suppressed when the bicycle is driven. Further, the base portion 4 having a small rising angle θ1 from the tread surface 10 is hardly deformed during driving and supports the block portion 3 connected by the peripheral wall surface 40 having a large taper amount from below. Particularly in this example, since the taper amount of the front peripheral wall surface 40a is large, the block portion 3 can be firmly supported against the load from the front in the traveling direction during driving.

  As a result, the rolling resistance generated by the deformation of the knob 2 during driving is small, and the driving force is efficiently transmitted to the road surface. Further, even when a load is applied to the knob 2 from a direction other than the traveling direction, such as during braking or cornering, the base portion 4 supports the block portion 3 to suppress deformation of the knob 2, Because it prevents wear and damage, it has excellent braking performance, cornering performance and durability.

  Further, since the connecting portion C of the base portion 4 and the block portion 3 is indented inward, the top surface 21 and the bottom surface 22 are linearly connected by the peripheral wall surface 20 as shown in FIG. Since the volume is smaller than that of the oval shaped knob 2, the weight of the bicycle tire 1 can be reduced without reducing the contact area between the knob 2 and the road surface.

  The angle formed by the tread surface 10 and the peripheral wall surface 40 of the base portion 4 and the angle formed by the peripheral wall surface 40 of the base portion 4 and the peripheral wall surface 30 of the block portion 3 are both large obtuse angles. Therefore, as shown in FIG. 3, the groove G between the knobs 2 expands toward the tip of the knob 2. For this reason, the groove G is not easily clogged with mud, and the clogged mud is smoothly discharged. In particular, in this example, since the block portion 3 is formed in a tapered shape, the mud is more difficult to clog and the clogged mud is easily discharged.

As described above, the bicycle tire 1 of this example is excellent in all of the performances of running performance, maneuverability, braking performance, cornering performance, durability, and mud repellency. Therefore, it can be widely used for off-road bicycles having different uses and running conditions.
Further, in this example, the flat surfaces 31a and 31b constituting the peripheral wall surface 30 of the block portion 3 are disposed with respect to the traveling direction of the bicycle tire 1, and the flat surfaces 31c and 31d are disposed in parallel with the traveling direction. Therefore, the load from the front, rear, left and right in the traveling direction can be received by the entire plane. Therefore, the base part 4 and the block part 3 are not easily torn. In addition, since the base part 4 is a truncated cone, the base part 4 can support the block part 3 and suppress deformation to be small even with respect to a load from any direction. Are better.

<Embodiment 2>
FIG. 4 shows a bicycle tire in which knobs 2 having different configurations are arranged.
The knob 2 in this example has a configuration in which a rectangular column block 3 is connected to a base 4 made of a quadrangular pyramid, and the base 4 is similar to that of the first embodiment described above. As shown in FIG. 4, the rising angle θ1 of the peripheral wall surface 40a is set to rise from the rear and left and right side peripheral wall surfaces 40b so that the taper amount of the peripheral wall surface 40a located in the forward direction of the bicycle tire 1 is increased. It is formed to be smaller than the angle θ3.

The peripheral wall surface 40 of the base part 4 is composed of flat surfaces 41a to 41d, and the peripheral wall surface 30 of the block part 3 is composed of flat surfaces 31a to 31d. As shown in FIGS. The four planes of the peripheral wall surfaces 30 and 40 are overlapped in two upper and lower stages so as to be continuous through the connecting portion C.
Since the bicycle tire 1 of this example has such a configuration, the rolling resistance generated by the deformation of the knob 2 during driving is small and the driving force is efficiently transmitted to the road surface as in the first embodiment. Therefore, it is excellent in runnability and maneuverability.

When the knob 2 is deformed as shown by a broken line in FIG. 6 during braking or cornering, the block portion is supported by the base portion 4 so that the knob 2 is deformed. Because it can be kept small, it has excellent braking performance and cornering performance.
Further, since the knob 2 is prevented from being worn or damaged, it is excellent in durability. Particularly in this example, the knobs are arranged so that the planes 31a, 31b, 41a, 41b are parallel to the traveling direction of the bicycle tire 1 and the planes 31c, 31d, 41c, 41d are parallel to the traveling direction. 2 is arranged, the strength of the knob 2 is higher with respect to the load from the front, rear, left and right than in the first embodiment, and the durability is excellent.
Since the groove portion G between the knobs 2 expands toward the tip of the knob 2, mud is not easily clogged in the groove portion G, and the clogged mud is discharged smoothly. Are better.

* Others The bicycle tire according to the embodiment of the present invention is not limited to the bicycle tire.
In the above-described example, the block portions 3 are all formed in a quadrangular prism shape, but if the base portion 4 and the block portion 3 having different rising angles are connected in a two-stage structure, The block portion 3 may be cylindrical or polygonal.

Further, the base 4 is not limited to the above-mentioned elliptical frustum and square frustum, but may be a cone as long as it has a tapered cross section that can be connected to the peripheral wall 30 of the block 3. Even a table, a triangular frustum or a polygonal frustum may be used.
In the above-described example, the knob 2 having the same shape is arranged. However, the knob 2 is arranged so as to have different patterns in the center portion and the outer side of the bicycle tire in combination with the knob 2 having different shapes. Also good.

1 is a cross-sectional view of a bicycle tire according to a first embodiment of the present invention. It is a top view of the bicycle tire of FIG. It is a side view of the knob formed in the bicycle tire of FIG. It is a top view of the tire for bicycles of Embodiment 2 of the present invention. It is a side view of the knob formed in the bicycle tire of FIG. It is a front view of the knob of FIG. It is a top view which shows the conventional tire for bicycles. It is a side view of the knob formed in the conventional bicycle tire.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bicycle tire 10 Tread surface 2 Knob 21 Top surface 3 Block part 4 Base part 20, 30, 40, 40a-40c Peripheral wall surface 31a-31d, 41a-41d Plane (theta) 1, (theta) 2, (theta) 3, (theta) 4 Standing angle G Groove part

Claims (7)

In bicycle tires where multiple knobs are arranged on the tread surface,
The knob includes a base part having a trapezoidal cross section projecting from the tread surface, and a columnar block part connected to the top surface of the base part.
The block portion and the base portion are overlapped so that their peripheral wall surfaces are continuous, and the rising angle of the peripheral wall surface of the block portion with respect to the tread surface is the rising angle of the peripheral wall surface of the base portion A bicycle tire characterized by being larger than and 90 degrees or smaller. The bicycle tire according to claim 1, wherein
The bicycle tire according to claim 1, wherein the base portion has a center of a top surface to which the block portion is connected positioned rearward of a traveling direction of the bicycle tire with respect to a center of the bottom surface. The bicycle tire according to claim 1 or 2,
The bicycle tire according to claim 1, wherein the block portion occupies a height of one-third to two-thirds of a height of the entire knob. The bicycle tire according to any one of claims 1 to 3,
2. The bicycle tire according to claim 1, wherein the block portion has a prismatic shape, and a plane constituting the peripheral wall surface is arranged in a traveling direction of the bicycle tire. The bicycle tire according to any one of claims 1 to 4,
The bicycle tire according to claim 1, wherein the block portion has a tapered shape that expands toward a connecting portion with the base portion. The bicycle tire according to any one of claims 1 to 5,
The bicycle tire according to claim 1, wherein the base portion is a truncated cone. The bicycle tire according to any one of claims 1 to 5,
The bicycle tire is characterized in that the base portion is a truncated pyramid.

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