JPS638004A - Tyre for icy and snowy road - Google Patents

Abstract

PURPOSE:To prevent the occurrence of powder dust pollution, by a method wherein, in a spike tyre for a vehicle, the central part of a tread is elevated, spikes are aligned between the central part and a should part, and through regulation of a tyre pressure, the spikes are rendered effective or ineffective to a road surface. CONSTITUTION:With a tyre air pressure increased, tyre rigidity is increased, a tread central part 32 is brought into a protruded state, and a shoulder part 29 is brought into a state in that it is retracted from the central part 32. Thus, spikes 10 aligned closer to the shoulder part 29 are separated from a road surface 40, the spikes 10 are rendered ineffective. Inversely, if a tyre pressure is decreased, the central part 32 is retracted, the spike pins 10 are brought into contact with a road surface to create spike action. This constitution enables the spikes 10 to be brought to an effective or an ineffective position, and enables the occurrence of powder dust pollution due to the spikes.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a tire for use on icy and snowy roads that prevents damage to the road surface caused by the spikes of a spiked tire and the dust generated therewith.

Conventional technology During winter, the tires of vehicles running on snow-covered roads in cold regions have
Snow tires are mainly used, as well as studless tires with greatly improved tread parts and other parts, snow spike tires, tire chains made of metal or composite materials, etc. are also widely used. When driving on snow-covered roads, there is no major difference in performance for the purpose of driving safety among the above types. However, there is nothing comparable in performance to spiked tires on frozen roads, and spiked tires are effective and the most reliable for driving safety on icy and snowy roads.

In recent years, spiked tires, metal tire chains, etc. have been the subject of much debate as they are thought to damage roads and generate dust pollution. The difficult point of this problem is that there is no solution, so driving safety and environmental protection are in a trade-off relationship with road wear prevention. In today's motorized society, the victim and perpetrator are often the same person, which also complicates the problem.

If roads are sufficiently cleared and melted, there is no need to use spiked tires or tire chains. On major roads in West Germany, where snow removal is well done, the same summer tires can be used on expressways throughout the summer and winter.
They can run at the same speed. However, as a result of spraying and using salt on the road surface for many years to melt snow, salt damage has become evident. Salt pollution is difficult to recover from.

There is no immediate way to remove salt damage, and efforts have been made to reduce the amount of salt sprayed. There have been cases in which lawsuits have been filed, with some arguing that salt spraying should be stopped and spiked tires replaced, and others claiming that incomplete snow removal was the cause of the accident. The number of accidents caused by slips is also increasing, and there is an urgent need to take some countermeasures in terms of non-life insurance and corrosion damage to cars.

Since 1981, the Japan Automobile Tire Association has established self-restraint standards for the third time in relation to reducing the pollution of spiked tires, and has submitted reports along with test data to the relevant ministries and agencies each time, with some of the measures already in progress. However, there are technical limits to effective modifications such as the number of spikes driven, protruding dimensions, diameter, and diameter of the bottom plate from the standpoint of maintaining driving safety, and improvements cannot be made beyond these limits. There is. Even when driving on icy and snowy roads with spiked tires, safety is maintained during normal driving, and there is no wear on the road surface or generation of dust.

However, from cold regions to warm regions, from highlands to flatlands, from large cities to suburban cities, the difference in temperature between morning and evening, the presence or absence of wind, etc.
Due to changes in conditions, depending on the region, there may or may not be ice or snow on the road surface. Diverse changes become especially severe at the change of seasons. The only way to avoid damage caused by road spikes is to replace tires with regular tires each time you drive on roads in regions where there is no ice or snow.

Spiked tires are usually used as snow spike tires. The spike has a simple appearance with a pin fixed upright on the bottom plate, but the design has been carefully designed to prevent it from falling out or falling over, and to reduce wear on the tip that receives ground pressure. Hard alloys are used to avoid damage.

General-use spiked tires have spikes drilled into the tire with holes in the front for driving spikes into the tire. Tires that are not too soft are used to better retain the spikes. In some cases, spikes are driven into a tire with marks attached to the holes for driving the spikes.

When driving on icy and snowy roads, tires with relatively low pressure are used in order to widen the tire's contact area and increase grip, so spikes are given priority to the part of the shoulder where the contact pressure distribution is high. It is normal to be included. If the protruding dimension of the spike from the tread is too short, the injection friction will be insufficient, and if it is too long, it will damage the road surface and the phenomenon of falling will become stronger, reducing the effect. The current restriction on protruding size is 1.5 fins.

Regarding wear, the tread wears out faster than the ground-contacting parts of the spikes, so the protruding dimension of the spikes gradually increases as tire wear progresses.

As a result of tireless research and development, tires are durable,
He achieved a high level of development in athletic performance, etc.

Naturally, there was a demand for lower pollution with respect to spiked tires, and many considerations were made, but they were too complicated and large.
Since it is not effective or lacks durability, there is no one that has been put into practical use and widely used.

Problems to be Solved by the Invention The grip force of a tire is caused by adhesive friction and hysteresis friction, and the phenomenon is complicated due to the viscoelasticity of the material. On the other hand, there are various road surfaces such as dry paved roads, wet paved roads, soft snow roads, compacted snow roads, ice film roads, ice film roads, etc., and during climate changes such as snow melting season and snowfall season, especially long distance roads. While driving, a car passes through various road surfaces.

In order to reduce damage to road surfaces, it is important to classify the need for ice and snow tires by region, region, urban area, or surrounding area, broadcast information about road surfaces, and make them available for use. However, in that case, if it is possible to make the spikes effective at times, and largely eliminate their effectiveness if necessary, then the reduction in pollution from spiked tires will generally be possible. achieved.

Tires wear out with use. Since the tread portion normally wears out faster than the tip of the spike that touches the ground, the protruding dimension of the spike increases as it wears.

1.5 Even in light of the fact that regulations on the protrusion size are set in small increments of mm, it is important to adjust the protrusion size according to wear, preferably before the season of use, in order to reduce the pollution of spiked tires. It is a necessary means.

Means to solve the problem The grip force of a tire is the sum of the adhesive friction force between the road surface and the tread, and the hysteresis friction caused by unevenness of the road surface, deformation of the tread, and smearing caused by being pressed and moved. However, on icy, snowy or wet roads, the adhesion frictional force is greatly reduced, and most of the tire's grip is due to hysteresis friction.

Figure 4 shows the names of the structural parts of a tire, and the most effective way to deform a tire is to increase or decrease the air pressure. Gully resistance is also reduced. When the air pressure is lowered,
Deformation is dispersed in the sidewalls, beads, etc. If the air pressure of the tire is set to a relatively low pressure, the tire will deform when it receives ground pressure, increasing the contact area and making the spikes placed near the shoulder part more effective. The rigidity of the tread increases, the contact area decreases, the ground contact pressure in the center of the tread increases, and the effectiveness of the spikes near the shoulder area decreases. Even if you change the tire pressure, it has its own limits. For the safe driving of regular cars, it is desirable that the power consumption does not exceed 1.3 Kt/nJ at the lowest and 30 Kt/nJ at the highest.

As a first means of solving the problem, we focused on changes in the tread's contact area and ground pressure, which are caused by changes in tire air pressure, and in order to amplify these changes, spikes are inserted into the tread's contact surface. The central part of the tread, excluding the part near the shoulders, is made thicker and higher, including the button.

When increasing the height of the center part, it is prepared from the tread design stage along with the tread, rather than adding adhesive later, but other components are changed so as not to interfere with the characteristics of the tire as much as possible. Do not add.

As a second means of solving the problem, the spike body is made to have an expandable structure. To have a simple mechanism that can withstand instantaneous and continuous ground pressure, is compact, does not loosen, and does not have its expansion and contraction function impaired by foreign objects, rust, etc. As the height of the central portion of the tire's tread increases in the direction of contact with the ground, the effect of changes in air pressure becomes greater as far as the effectiveness of spikes is concerned, but the amount of adjustment of air pressure must be increased accordingly. Furthermore, when the air pressure is low, the deflection increases and the heat generated by the tire also increases. The thickness of the central part of the tread should be as small as possible in terms of heat generation and other factors, but since the current regulation on the protruding dimension of spikes is a maximum of 1.5 m, there is no need to make it very high. do not have.

By combining the above measures, we aim to reduce the pollution of tires for icy and snowy roads.

Action Figure 10 shows radial tires (G) and bias tires (H).
Fig. 1 is an explanatory diagram of changes in the contact surface of the tread when a load of 1 is applied. (30 is flexible and easily deformed. Deformed ground contact part f4N1@? When touching the ground, the bias tire () (+) tends to lift the part shown in the center. The figure report exaggerates this tendency. As shown in the diagram, this condition only occurs when the air pressure is extremely low or the load is high.

FIG. 1 is a partial perspective view of the tread of the tire, and FIG. 2 is a sectional view taken along line A-A at high air pressure.

The central part of the tread C3G, excluding the part near the shoulder part 29 where the spike flO is driven, is made thicker and raised with the slam. If the air pressure is high, the rigidity of the tire increases, and the central part of the tread G21 becomes higher.
The spikes, which were driven into the part of the shoulder that had become lower, moved in the direction away from the road surface 40.

When the air pressure of the tire is lowered, the contact area of the tread GO increases due to the deformation of the side wall G3, the shoulder part, the carcass 311°, the bead 39, and others, and as shown in FIG. approach and make contact. This separation and contact air pressure depends on the characteristics of the tire and the load on the tire. Tire deformation due to air pressure is sensitive and occurs reliably, and when the air pressure changes by α2 to α3Vd in regular tires for general passenger cars, it can be sensed from the driver's seat as a change in maneuverability and stability.

The hardness of the raised portion of the tread central portion G2 may be the same as that of the tread GO, and must not be too soft.

The spikes (Io) to be driven are not much different in external shape from conventional spikes as shown in Fig. 8.As shown in Fig. 7 exploded perspective view, the bottom plate αθ
The spike pillars (Iz) inscribed in the outer cylinder (14) having an outer cylinder (14) are connected to each other with screws (13 (Isu collection 2).

The screw (13α5 groove has a small lead, and in order to prevent loosening due to vibration and impact, a spring washer 08 is placed on the bottom plate side, and anti-slip protrusions 20-) are provided on the upper and lower surfaces of the spring washer 4, Recess 23 that fits into this
■Mutsumi, add on the spike pillar side, bottom plate α0. The dustproof cover 241 is provided to prevent the screw from being obstructed by foreign matter. The dustproof cover C< cannot prevent moisture from entering, so if the spike column t12, outer cylinder (141, spring washer (18) etc. are made of rust-prone materials, apply anti-rust treatment or During assembly, apply sticky oil to the inner surface.The spike α2 is screwed in using a tool through the screwdriver groove Qθ, and the height of the spike (10 is adjusted by the screwing. Adjustments are made when driving spikes for tires with different performance.To match the protrusion size, and when the protrusion size of the spike becomes too large due to tire tread wear.

It is for correction.

Adjustment of the protrusion size for wear does not need to be performed frequently. Depending on the degree of strike, the degree of wear is checked before each winter season.
Make adjustments only when necessary.

Example A partial perspective view of a tire for ice and snow roads is shown in FIG. 1 as an example.
FIG. 2 shows a cross section along line A-A when the tire has a high air pressure, and FIG. 3 shows a cross section along line A-A when the tire has a low air pressure.

The tread center part 3z of the tread Go is a part raised in the direction of contact with the ground, and between this and the shield part 4,
Spikes [10 (
1 (to) are arranged and poured. As shown in Figure 2, as the air pressure of the tire is increased, the tire becomes more rigid, and while it can bear the load, the tips of the spikes will not touch the road surface! It changes in the direction away from 4G, no longer makes contact with the road surface (40), and separates. When driving in this condition, the contact area decreases and the contact pressure at the center of the tread increases, so the spike aaam and injection friction Loss of power. Or due to unevenness of the road surface, or during sudden braking or sharp turns, the vehicle will come into contact with the road surface (40, but except in extreme cases,
The contact is caused by the height of the tread center G2.
It becomes lighter. This is also due to the tire's inherent excellent performance, which enables safe driving. Lowering the tire pressure reduces stiffness and reduces the shoulder part 2.
9. Along with sidewall C33 etc., tread (3()
The carcass (31
1 was also pushed a little inside the tire, and the spikes acxtoa'
xy> The tip transitions in the direction approaching the road surface 10 as shown in Fig. 3, and if the tire air pressure is appropriate, depending on the load,
The tip of the spike αcmacn.

Strengthen the contact with the road surface 40. When driving on icy and snowy roads in this condition, the injection friction of spikes (tolG (b)) is affected by the load depending on the type of vehicle that is applied to the road surface. is flexible and deforms in a relatively diverse manner, and it is possible to use tires with different shapes depending on the characteristics of the tire, such as the width of the tire.
(Showed in Fl.

Effects of the Invention The standard air pressure for both high and low levels and the standard protrusion dimensions of spikes are displayed on tires for each tire performance type, and the
The driver can adjust the effectiveness of the spikes by changing the tire pressure using a stationary compressor or a portable air cylinder, based on a fairly wide range of road surface information, such as urban areas and roads with good snow melting. It can be controlled. It is also caused by changes in the protruding dimensions of the spikes due to wear and tire performance. Depends on air pressure. The protrusion dimension can be adjusted according to the difference in tread deformation.

The Japan Automobile Tire Association has reported to related ministries and agencies for the third time since 1981, regarding the number of spikes, diameter, protrusion dimension, and ground contact of spikes, which are effective means of reducing the pollution of spiked tires. Among issues such as the shape of the surface, the diameter of the spike bottom plate, etc., problems related to the protrusion dimension, which is an effective but difficult method, can now be controlled by injection friction, and the reduction in pollution of tires for ice and snow roads with spikes is approximately achieved.

[Brief explanation of the drawing]

Fig. 1 is a partial perspective view of the tire tread. Fig. 2 is a cross-sectional view of the tread section taken along the line A-A when the air pressure is high. Fig. 3 is a cross-sectional view of the tread section taken along the line A-A when the air pressure is low. , Name diagram of the structural parts of a general tire. Figure 5 is a plan view of the spike. Figure 6 is a BB sectional view of the spike. Figure 7 is an exploded perspective view of the spike. Figure 8 is an external perspective view of the spike. FIG. 9 is a cross-sectional view of another example trend. FIG. 10 is an explanatory diagram of ground contact area change. 1O...Spike 12...Spike column 14...
・Outer cylinder 16...Bottom plate 18...Spring washer 2020...Protrusion 2222a...Recess 24...
...Dust cover 26...Screw groove 28...Tire 29...Shoulder part 30...Tread
31...Carcass 32...Trend center part 33...Side wall 35...Bead 40...
・Road surface

Claims (1)

[Claims] 1. In a tire for icy and snowy roads of a vehicle, the tread of the tire (
30), including the pattern, is made higher in the direction of ground contact, and the center part (32) and shoulder part (29) are raised higher in the direction of ground contact.
), along both sides of the central part (32), there are spikes (
10) A tire for icy and snowy roads arranged and installed. 2. The spike (10) has an outer cylinder (
14) and a spike column (12) to which a dustproof cover (24) is fixed and which has a screwdriver groove (26) are inscribed so as to be threaded by screws, and the spike column (12) and the bottom plate (1
6), a spring washer (18
), and the bottom plate (16) and the spike pillar (12) are provided with recesses that fit into the protrusions.