1. 轮胎模具简介
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According to the shape
Tread patterns in commercial tires can be roughly divided into four groups according to the shape: 1. Asymmetric, [asi’metrik] 2. Unidirectional, 3.Rib shape, 4.Block shape.
In practice, the design of a tire tread pattern also requires the balancing of many contradictory demands. Finding the proper structure that balances these demands for any given tire is thus a great challenge. For this and other reasons, engineers typically focus on a large array of considerations, placing emphasis on certain design criteria over others, depending on the specific application of the tire. However, by focusing on certain design criteria, other criteria such as tire wear or stress components may not have been weighed as heavily during the design stage.
Tire Tread Pattern Design
Tire design and more specifically tread pattern design plays a critical role in the safe and efficient operation of a vehicle. For example, it is known that the tread pattern assists in the generation of 1. steering forces, 2. driving, 3. braking forces. 4. reducing road noise, 5. providing superior grip capabilities in both wet and dry driving conditions, 6. minimizing rolling resistance to increase the overall fuel economy of the vehicle.
All season type tires
All season tires have somewhat laterally extending grooves in each shoulder of the tread . These lateral grooves enhance snow traction performance.
In any event, tire patterns have common pattern traits. These common pattern traits include, for example, grooves with sharp or acute angles in transitional areas, e.g., between treads , vertical walls forming the grooves or treads , etc. It has been theorized that such designs have large stress components which conjugate at the sharp angles, as well as result in increased road noise and rolling resistance. Of course, engineers are constantly designing tread patterns to increase overall tire efficiency, but these design traits remain pervasive.
By way of a more specific illustration , one design approach has been to form grooves between ribs with negatively sloped walls to increase gripping capabilities. However, in such an approach, the grooves are more likely to trap and retain stones, which can damage the tire. Another example is in the use of all-season tires, which customarily employ block elements in their tread design. These designs have superior grip performance but tend to have increased noise level, as well as have a tendency toward irregular wear due primarily to their lack of stiffness in the circumferential direction of the tread . Such noise generation and irregular wear are accentuated at acute or sharp angles in the rubber blocks formed by intersections of groove walls.
Generally Tire
Tires generally have a tread that is well-suited for a specific vehicle application. For example, pneumatic tires used primarily on paved surfaces generally have a high proportion of the tread in contact with the road. These tires generally have a net-to-gross ratio in excess of 70%.
Final design factors
In examining the complex mechanisms involved in proper tread pattern design, several factors play a role in the final design of the tread pattern . These factors include, 1. Industry standards, 2. Government regulations, 3. Customer specifications, 4. Marketing requirements and the like.
According to functions
But, if according to functions of the tire, the tire can be divided into: 1. Generally tire, 2. All season tire, 3. Snow tire, 4. On/off the road tire, 5. Off the road tire.
Snow Tires
If, however, the vehicle owner wants increased traction on snow, tires having a more aggressive open tread pattern have been used for this purpose. These snow tires generally have a lower net-to-gross ratio and almost always a large amount of leading edges on block elements to provide increased traction.
Complex design mechanisms
On the other hand, the complex mechanisms which are taken into account in the design of the tread pattern include, 1. Amongst other mechanisms, 2. Stresses generated upon the tire during driving conditions, energy losses due to rolling resistance, 3. Sidewall flexing, To a host of other mechanisms. Thus, the design of a tread pattern is not a trivial task and, in fact, is quite complex requiring the need to take into account many different considerations.
This means that 70% or more of the area within the tires' footprint or contact patch is touching the road while 30% less is the void area representing the tires' grooves within the footprint area. These tires, due in part to the large amount of tread in contact with the road, can yield very good tread mileage sometimes in excess of 75,000 miles during the tires' normal life.
Off-Road Tire
Typically, a serious off-road enthusiast may choose a tire designated as a mud tire. These tires are very open, tending not to clog in the mud.
Skidproof pin
On/Off Road Tire
When the vehicle owner wants a tire that can operate both on the roadways as well as in snow, mud and sand, he generally must select an on/off road tread .
The Goodyear WRANGLER MT. The MT, mud tire designation has signified to off-road enthusiast that the tire was well-suited for offroad applications. A measure of the tires' off-road worthiness was one of its first applications, the U.S. Army Hummer vehicle.
Tire Moຫໍສະໝຸດ Baiduld
Background of The Tire
In order to have better understanding about the tire mould, we get to have a clear mind about the tire categories specifications.