JPH0262401B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a spiked tire used for driving a car safely on a frozen or snowy road.

[Prior Art] In cold, snowy regions like Hokkaido, tire chains, spiked tires, etc. are used to allow cars to drive safely on roads covered with ice or snow. Therefore, compared to tire chains that are only attached and used when the road surface is snowy or frozen, spiked tires, in which the spike pins always protrude from the tire surface, are more convenient because it saves the trouble of attaching and detaching the chain. As a result, most cars are now equipped with spiked tires.

However, in recent years, due to advances in road snow removal technology and an increase in traffic volume, roads are often left exposed even during snowy conditions, and the distance traveled that requires spiked tires has become extremely short. There is. For example, in Hokkaido, it is estimated that this distance is only about 5% of the total distance traveled using spiked tires.

If spiked tires, which have hard metal spike pins embedded in the ground contact surface of the tire, which are conventionally used on roads that are free of ice and snow, are used, they will cause damage to the road surface, wear and tear, and the resulting damage to the road surface. Problems such as dust generation occur. However, from the viewpoint of safe driving of automobiles in snowy areas, the above-mentioned spiked tires are effective. Therefore, it is desired to solve the above-mentioned problems that occur when spiked tires are used in non-frozen and non-snowy conditions.

[Problems to be Solved by the Invention] The present invention provides a spiked tire as described above, in which the temperatures of the tire and spike pins are different when the car is running on roads that are frozen or covered with snow and roads that are not covered with ice or snow. By focusing on the difference in temperature, the company took advantage of this difference in temperature to make the spike pins protrude from the tires when driving on frozen or snowy roads, but when driving on roads that are free of ice and snow. When doing so, the spike pin should be constructed so that it automatically goes into the pin hole, and the movement should be done as quickly as possible to minimize damage to the road surface caused by spiked tires, abrasion, and the generation of dust caused by the spiked tires. The technical challenge is to prevent this.

[Means for Solving the Problems] In order to solve the above problems, the spike tire of the present invention has pin holes provided in the ground contact surface of the tire body.
A spike pin that has a flange portion at the base end and whose tip portion can freely protrude and retract from the pin hole, and a spike pin that is disposed between the flange portion of the spike pin and the bottom surface of the pin hole, and that the spike pin is always attached in the protruding direction. The spike is disposed in contact with the biasing force of the disc-shaped spring and the flange of the spike pin, and the spike is heated by the heat generated by the tire and restores to its memorized shape against the biasing force of the disc-shaped spring. The tire is characterized by the provision of a dish-shaped actuating member made of a shape memory alloy that allows the pin to sink into the tire body.

[Function] When driving on a frozen or snowy road surface using the above-mentioned spiked tires, since the tires are in a low temperature state, the actuating member made of a shape memory alloy maintains a plastic state where it can be easily deformed. The spike pin is kept protruding from the tire at all times by a disk spring.

On the other hand, when driving on roads that are free of ice or snow, the temperature of the shape memory alloy actuating member rises due to the heat generated by the tires during driving, and the actuating member made of a shape memory alloy resists the biasing force of the disk spring and changes to its memorized shape. For restoration, the spike pin is recessed into the pin hole.

In particular, when the disk-shaped actuating member made of a shape memory alloy becomes plastic and flattens due to the urging force of the disk-shaped spring, it comes into contact with the flange portion of the spike pin over a wide area, so the spike pin The heat transferred through the actuating member is quickly conducted to the actuating member, and the actuating member is significantly accelerated.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

1 and 2 show embodiments of the invention, each representing a different operating state. In these figures, 1 indicates the tire body, 2 indicates a pin hole for accommodating a spike pin provided on the ground contact surface of the tire body 1, and the inner bottom of the pin hole 2 has an enlarged diameter portion 2a.
is formed.

The spike pin 3 fitted into the pin hole 2 has a flange portion 3a at its base end which is fitted into the enlarged diameter portion 2a.
The tip portion 3b can freely protrude and retract from the pin hole 2, and the flange portion 3a of the spike pin 3
A dish-shaped spring 4 is disposed between the spike pin 3 and the bottom surface 2c of the pin hole 2 to bias the spike pin 3 in the direction of protruding from the pin hole 2. The bottom surface 2c of the enlarged diameter portion 2a of
A dish-shaped actuating member 6 made of a shape memory alloy and having a hole in the center is disposed between the opposing surface 2d and the flange portion 3a in contact with the flange portion 3a.

The actuating member 6 made of the shape memory alloy is easily deformed by external force when its temperature is maintained below the transformation temperature at which it returns to its memorized shape and is in a plastic state. When the temperature rises above the transformation temperature due to the temperature rise in step 3, the property restores from the appropriate shape of the plastic state to the memorized shape, and the flange portion 3a of the spike pin 3 resists the biasing force of the disc spring 4. It is pressed in the direction of the bottom surface 2c of the pin hole.

Various types of shape memory alloys are already known, and the temperature for restoring the memory shape can be freely set depending on the proportion of the alloy. The transformation temperature at which the actuating member 6 formed of the shape memory alloy is restored to its memorized shape is appropriately set depending on the type of vehicle and the weather conditions of the region in which the vehicle travels.

When driving on a frozen or snowy road surface using a spiked tire having the above configuration, since the tire is in a low temperature state, as shown in FIG. Since the spike pin 3 is maintained in this state and is compressively deformed into a flat plate shape by the biasing force of the disc-shaped spring 4, the spike pin 3 is maintained in a state protruding from the ground contact surface of the tire body 1.

On the other hand, when driving on a road that is free of ice or snow, the temperature of the actuating member 6 made of a shape memory alloy rises due to the heat generated by the tires and spike pins 3 during driving, and the biasing force of the disk spring 4 increases. The spike pin 3 is accommodated in the pin hole 2 in a recessed state in order to restore the disk-shaped memorized shape as shown in FIG.

In particular, when the disc-shaped actuating member 6 becomes plastic and flattens due to the biasing force of the disc-shaped spring 4, it becomes flat and comes into contact with the flange portion 3a of the spike pin 3 over a wide area. , the heat transmitted through the spike pin 3 is quickly conducted to the actuating member 6, and the actuating member 6 is accelerated.

[Effects of the Invention] As described above, according to the spiked tire of the present invention, on a frozen or snowy road surface, the actuating member made of a shape memory alloy maintains a plastic state that easily deforms due to temperature drop, and does not fit into the pin hole. The biasing force of the disc-shaped spring keeps the spike pin protruding from the pin hole, ensuring safe driving of the car, and even when the car is driving on a road surface that is free of ice and snow. As the temperature rises, the restoring force of the moving member made of shape memory alloy suppresses the biasing force of the dish-shaped spring, and the spike pin automatically sinks into the pin hole. The generation of dust associated with this can be prevented.

Moreover, in the present invention, since the disk-shaped actuating member made of a shape memory alloy is disposed in contact with the flange portion of the spike pin, it becomes plastic and becomes flattened by the biasing force of the disk-shaped spring. When you do,
It makes contact with the flange of the spike pin over a wide area,
The heat transmitted through the spike pin is quickly conducted to the actuating member, significantly speeding up the actuation of the actuating member. By performing such a quick operation, damage to the road surface caused by spiked tires, wear and tear, etc. can be prevented as much as possible.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a sectional view showing its different operating states. 1...Tire body, 2...Pin hole, 2c...Bottom surface, 3...Spike pin, 3a...Flange part,
3b...Tip portion, 4...Dish-shaped spring, 6...Operating member.

Claims (1)

[Scope of Claims] 1. A spike pin having a flange portion at its base end in a pin hole provided in a ground contact surface of a tire body, and a tip portion of which can freely protrude and retract from the pin hole, and the flange portion of the spike pin and the pin hole. A dish-shaped spring is disposed between the bottom surface of the spike pin and constantly biases the spike pin in the projecting direction, and a disc-shaped spring is disposed in contact with the flange of the spike pin, and is heated by the heat generated by the tire. A spike tire comprising: a disk-shaped actuating member made of a shape memory alloy that causes the spike pin to sink into the tire body by restoring the spike pin to a memorized shape against the biasing force of a disk spring.