JP2000085643A - Track belt for snowmobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a track belt for snowmobiles that can remarkably improve the high-speed travel performance of snowmobiles via suppression of its own heat generation during high-speed travel and thus prevention of separation of tractive projections from its reinforcing layer. SOLUTION: An outer reinforcing woven fabric 10a includes a tenacity- increasing polyester yarn, and an upper cover layer 11a has tractive projections 13 whose rubber properties are determined to have a loss tangent tanδ at 60 deg.C of not more than 0.2. This constitution suppresses heat generation of a track belt body 3A to prevent separation of the tractive projections 13 from the outer reinforcing woven fabric 10a and improves high-speed travel performance remarkably as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a snowmobile track belt, and more particularly, to a snowmobile track belt capable of suppressing heat generation of the track belt during high-speed running and improving high-speed running performance. is there.

[0002]

2. Description of the Related Art Conventionally, as a configuration of a snowmobile traveling on snow, for example, as shown in FIG. 2, one or two skis 2 for steering are provided at a lower front part of a vehicle body 1 and a rear part thereof is provided. Has an endless track belt (infinite track belt)
3 is provided.

The output from the engine 4 is transmitted to the track belt 3 via the automatic transmission 5 and the wheel sprocket 6, and transmitted to the snow surface by the track belt 3. Reference numeral 7 denotes a suspension rail of the track belt 3, and reference numeral 8 denotes a steering handle.

The track belt 3 is constructed, for example, as shown in FIG. 3 by reinforcing outer and inner layers on upper and lower portions of a core 9 made of a polyester cord disposed along the longitudinal direction of the track belt 3. The woven fabrics 10a and 10b are provided, and the upper and lower portions thereof are covered with upper and lower cover layers 11a and 11b made of a rubber-like elastic body or the like, and further, between the core 9 and the reinforcing woven fabrics 10a and 10b. , Track belt 3
A lateral rigid member 12 (rod) is buried at a predetermined interval in the longitudinal direction of the track belt 3 and in the width direction of the belt body 3 in order to reinforce the surface rigidity of the snow contact surface.

Further, on the upper cover layer 11a, traction projections 13 are formed at predetermined intervals in the longitudinal direction and parallel to each other at predetermined intervals, and on the lower cover layer 11b, driving projections meshing with the pins of the wheel sprocket 6 are provided. 14 are integrally formed at predetermined intervals.

[0006]

By the way, the reinforcing woven fabric 10a on the outer layer side of the track belt 3 as described above functions to protect the core body 9 from damage and hold the lateral rigid material.
Due to the recent improvement in the performance of snowmobiles, the function of holding the lateral stiffness material is insufficient, and the outer reinforced fabric 1
0a and breakage of the lateral rigid member 12 occurred.

In order to increase the strength of the reinforced woven fabric, a measure has been taken to change from nylon to polyester. However, polyester has a lower adhesiveness to rubber than nylon, so that the pulling projection 13 is not used. Problem occurs that the part of the reinforcing layer is separated from the reinforcing woven fabric 10a constituting the reinforcing layer,
There were limits to improving high-speed driving performance due to the occurrence of fatal accidents.

SUMMARY OF THE INVENTION It is an object of the present invention to suppress heat generation of a track belt during high-speed running, to prevent a traction projection from peeling off a reinforcing layer, and to dramatically improve high-speed running performance of a snowmobile. It is an object of the present invention to provide a snowmobile track belt.

[0009]

According to the present invention, in order to achieve the above object, the rubber properties of the traction projection provided on the upper cover layer are set so that the loss tangent tan δ (60 ° C.) is 0.2 or less. It is the gist. Further, a polyester yarn is provided in the reinforcing layer on the outer layer side.

[0010] The present invention is constructed as described above, wherein a polyester yarn is disposed on the outer reinforcing layer, and the outer reinforcing layer has a function of holding the lateral rigid member. By setting physical properties to predetermined values,
The heat generated by the track belt can be suppressed, the peeling is prevented, and the high-speed running performance of the snowmobile is improved.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The same components as those of the conventional example are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 1 is a partially enlarged cross-sectional view of a track belt main body 3A taken along the line AA of FIG. 3 showing an embodiment of the present invention. Reference numeral 9 denotes a core made of polyester cord; And outer and inner layers of reinforcing woven fabric disposed on the upper and lower portions of the core body 9, respectively.
b, an upper cover layer 11a having a traction protrusion 13 on the surface and a lower cover layer 1 having a drive protrusion 14 on the surface.
1b is provided.

A transverse rigid member (rod) 12 is arranged between the core 9 and the reinforcing woven fabric 10b on the inner layer side in the width direction of the track belt body 3A. According to the present invention, the outer layer reinforcing woven fabric 10a (reinforcing layer) disposed on the upper portion of the core body 9 made of polyester cord and the traction projection 1 made of rubber material are used.
The cause of the separation of the upper cover layer 11a provided with the upper cover layer 11a is caused by the fact that the track belt body 3A generates heat during high-speed running, and the adhesive strength between the outer layer reinforcing woven fabric 10a and the traction projections 13 and the upper cover layer 11a is reduced. This was discovered from various experimental results.

That is, the outer layer reinforcing woven fabric 10a (reinforcing layer)
By arranging a polyester yarn to increase the strength and setting the rubber properties of the traction projections 13 provided on the upper cover layer 11a such that the loss tangent tan δ (60 ° C.) becomes 0.2 or less, the track belt is improved. The main body 3A can suppress heat generation, prevent peeling between the outer layer reinforcing woven fabric 10a (reinforcing layer) and the traction projections 13, and dramatically improve high-speed running performance. In addition, the curvature radius R of the lateral rigid member hem of the outer layer reinforcing woven fabric 10a (the reinforcing layer) is set to 8 mm.
By setting the value larger than that, heat generation can be prevented.

According to the results of the durability test on the indoor bench, by setting the loss tangent tan δ (60 ° C.) to be 0.2 or less, the durability (peelability) (%) is increased by about 5 times. By setting the radius of curvature R of the lateral rigid member hem of the outer layer reinforcing woven fabric 10a (reinforcing layer) to be larger than 8 mm, the durability (heat generation) (%) can be extended about 5 times. Even if a polyester yarn is disposed on the outer layer reinforcing woven fabric 10a, the rubber physical properties of the traction projections 13 are reduced by the loss tangent tanδ (60
(C) is set to 0.2 or less, the durability (peelability) can be extended about three times.

The test conditions of the indoor bench endurance test were as follows: speed: 160 km / h, load: 1530 N. Judgment was made by comparing the running distance up to the occurrence of failure (peeling) with 100% as a reference.

The measurement conditions for the loss tangent tan δ (60 ° C.) are measured by an extension type viscoelasticity measurement. Frequency 20H
g, elongation 10 ± 2%. As described above, the outer layer reinforcing woven fabric 1
0a (reinforcing layer) is provided with a polyester yarn to provide a function of holding the lateral rigid member, and furthermore, the arrangement of the outer reinforcing layer and the physical properties of the rubber of the traction protrusion are reduced by a loss tangent tanδ (60 °
By setting C) to be 0.2 or less, heat generation of the track belt can be suppressed, peeling is prevented, and the high-speed running performance of the snowmobile is improved.

[0018]

According to the present invention, the rubber properties of the traction projections provided on the upper cover layer as described above are determined by the loss tangent tanδ (60 °
C) is set to be 0.2 or less, suppressing heat generation of the track belt during high-speed running, preventing the towing projections from peeling off the reinforcing layer, and dramatically improving the high-speed running performance of snowmobiles. Can be done.

[Brief description of the drawings]

FIG. 1 is a partially enlarged cross-sectional view of a track belt main body, showing an embodiment of the present invention, taken along a line AA in FIG.

FIG. 2 is a schematic configuration diagram of a conventional snowmobile.

FIG. 3 is a partially cutaway perspective view of a conventional track belt.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Body 2 Ski 3 Track belt (infinite track belt) 4 Engine 3A Track belt body 5 Automatic transmission 6 Wheel sprocket 7 Suspension rail 8 Steering handle 9 Core body 10a, 10b Reinforcement woven cloth of outer and inner layers 11a, 11b Upper and lower cover layers 12 Lateral rigid member 13 Traction projection 14 Drive projection R Radius of curvature of lateral rigid member skirt

Claims (2)

[Claims] An upper cover layer provided with traction projections via a reinforcing layer and a lower cover layer provided with drive projections are provided on upper and lower portions of a core body provided along a longitudinal direction of a track belt main body. In a snowmobile track belt, a lateral rigid member is embedded between the core and the reinforcing layer at a predetermined interval in the longitudinal direction of the track belt main body and in the width direction of the track belt main body. A snowmobile track belt wherein the rubber properties of the traction projections provided on the upper cover layer are set so that the loss tangent tan δ (60 ° C.) is 0.2 or less. 2. The snowmobile track belt according to claim 1, wherein a polyester yarn is disposed on the reinforcing layer on the outer layer side.