JPH0455881B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a solid rubber tire suitable for so-called capsule vehicles used for conveyance within steel pipelines. In general, a capsule vehicle has, for example, five solid tires c mounted on the front and rear surfaces of a container-shaped vehicle body b, as shown in FIG. It is transported while rotating in a spiral pattern, powered by the wind pressure. For example, the solid tire c used in such a capsule vehicle d is required to have a small wheel outer diameter and a high load capacity, but on the other hand, characteristics such as ride comfort are not required, and conventionally, as shown in Fig. 2, The tread rubber f bonded to the baseband e is made of polyurethane with a large load-bearing capacity or a rubber compound with relatively high hardness, and the cross section is approximately trapezoidal, and the thickness of the rubber is set to be thin in the range of 15 to 35 mm. The main point was to suppress the heat generated by the tires while running. Therefore, depending on the location of the plant, problems such as severe vibration and noise during running may occur. For example, when operated at a maximum load of 1600 kg and a speed of 36 kp, the vibration noise reaches approximately 80 dB, which becomes a source of pollution, causing the problem that pipe a cannot be laid, especially near private residences. Furthermore, since the solid tires used in capsule liners are always rotating with a slip angle, the side hoses are always working on the adhesive interface between the baseband and the tread rubber. For this reason, if the adhesive force at the interface is equivalent to that of a general solid tire, interfacial delamination damage will occur and this will grow, significantly reducing the tire's durable life. Therefore, in order to alleviate impact vibrations that generally cause noise when tires are running, it is necessary to increase the thickness of the tread rubber and to adopt materials and structures that increase the tire's deflection characteristics. However, the heat generated by running a tire generally increases in proportion to the thickness of the rubber and the deflection of the tire, so if the tire was designed in this way based on conventional wisdom, the heat generated by the tire would increase and its durability would be shortened. will decrease significantly. The present invention was completed as a result of various studies regarding the formulation and shape of treaded rubber in order to satisfy the required characteristics of reducing vibration noise and maintaining adhesive durability.
A treaded rubber made of a rubber component made by mixing 0 to 25% by weight of polybutadiene rubber with 20 to 60 parts by weight of carbon black with a particle size of 250 to 70 mμ is vulcanized and adhered to the outer peripheral surface of the baseband. The contact surface of the tread rubber is a plain without grooves, and the wall thickness of the tread rubber is 13 mm of the outside diameter of the tire.
-19%, and in the axial cross section of the tread, in the area where the tread rubber is adjacent to the baseband, the tread rubber must have a side surface shape that transitions from a concave groove to a convex part from the end of the baseband toward the tread shoulder. It is characterized by An embodiment of the solid tire of the present invention will be described below with reference to the drawings. In FIG. 3, a solid tire 1 of the present invention is shown.
In this case, a tread rubber 4 is vulcanized and bonded onto a baseband 2 via an adhesive layer 3. Treaded rubber 4
The ground contact surface 6 is formed to have a cross-sectional arc having a radius of approximately 150 to 600 mm, the ground contact surface 6 is plain, and the thickness TH of the tread rubber is 50 to 70 mm. Increasing this wall thickness increases the deformation of the tire, so with conventional compounded rubber for treads, the tire generates a lot of heat and becomes unusable, but with the compounded rubber for treads based on the present invention, the internal energy of the rubber increases. Since the loss (hysteresis) is small, the heat generation of the tire is significantly reduced. Therefore, even if the tire is designed to have a thicker wall thickness to increase absorption and relaxation of impact force, the heat generated by the tire during running can be suppressed to a level that does not pose a problem. Next, on the side surface 5 of the tread rubber 4, a concave groove 7 is formed in the tire circumferential direction in an area adjacent to the baseband 2, and the contact surface side of the concave groove 7 smoothly transitions to the convex portion 8. ing. Then, a required number of vent holes with a diameter of 1.5 to 2.5 mm are provided at positions in the mold corresponding to the convex portions 8. This uneven shape suppresses the flow of the rubber 4 near the adhesive interface, preventing the attachment layer 3 from flowing out to both ends of the baseband 2 as in the conventional case, and reducing the adhesive force between the baseband 2 and the tread rubber 4. is avoided. Further, by providing a vent hole in the convex portion 8, the rubber 4 near the tire side surface 5 moves in the direction of the vent hole, and the flow of the rubber 4 adjacent to the adhesive layer 3 is effectively suppressed. Furthermore, providing the grooves 7 and the convex portions 8 is highly desirable from the viewpoint of alleviating stress concentration at the end of the adhesive interface between the tread rubber 4 and the baseband 2, and contributes to maintaining and improving adhesive strength. It's a big deal. The treaded rubber 4 is a composition using a rubber component made of natural rubber alone or a mixture of natural rubber and 25 parts by weight or less of butadiene rubber, and soft carbon black with a particle size of 250 to 70 mμ and other ordinary rubber compounding agents. It is formed. As for the composition of the tread rubber 4, conventionally used tread rubber formulations and urethane rubber have high hardness and cannot sufficiently absorb impact vibrations. Furthermore, the internal heat generation of the rubber is high and sufficient durability cannot be exhibited. Therefore, the above-mentioned blended composition is used. If the butadiene rubber exceeds 25 parts by weight, impact fracture resistance and chipping resistance will decrease, which is not preferable. Also, the particle size of carbon black is 250~
A rubber having a diameter in the range of 70 mμ is used, but if it is smaller than 70 mμ, the resilience of the rubber decreases and energy loss increases. On the other hand, if it exceeds 250 mμ, reinforcing properties will deteriorate, which is not preferable. Furthermore, from the viewpoint of the balance between the heat generating properties and reinforcing properties mentioned above, the filling amount of carbon black is determined by the rubber component.
The amount ranges from 20 to 60 parts by weight per 100 parts by weight. In addition, in the blending of treaded rubber 3, 3 to 5 parts by weight of zinc oxide is blended with respect to 100 parts by weight of the rubber component.
As the blending amount increases, the thermal conductivity improves, but the elongation at break tends to decrease. In addition, ordinary rubber chemicals such as stearic acid, anti-aging agents, and vulcanizing agents are added to the composition of the treaded rubber 3, but no softening agents such as oil are added. In addition, in the solid tire 1 of the present invention, the upper surface of the base band 2 is roughened by sandblasting or shot blasting, then degreased and cleaned with a solvent such as trichloride, and after drying, an adhesive is applied to the surface of the base band 2. Coloring, pasting, roll,
A sheet of the above-mentioned treaded rubber composition kneaded with a Banbury etc. is calendered to be slightly wider than the width of the baseband 2, and then wrapped around the outer peripheral surface of the baseband 2 until a predetermined diameter is obtained to form a raw cover. The tire is placed in a predetermined mold attached to a vertically operating press and vulcanized for a predetermined period of time by applying a pressure of 100 kg/cm ² or more and a temperature of 130 to 160° C. to the cross section of the tire. As described above, since the solid tire of the present invention is constructed by combining tread rubber with a predetermined compounded rubber in terms of wall thickness and shape, it has a high ability to absorb shock vibrations caused by the running of the capsule, and also prevents peeling of the adhesive interface between the tread rubber and the baseband. effectively prevent damage,
Excellent durability and vibration noise reduction can be achieved. Example Tire outer diameter 375mm, tire width 147mm, tire inner diameter
A 288mm solid tire with the specifications shown in Table 1 was prototyped. This is shown in Figure 1.

【table】

[Table] Attached to the sea urchin capsule car, inner diameter 1000mm, length 3.6
The temperature rise and vibration noise of the tires were measured in a steel pipe line with km at a speed of 36 km/h and a load of 1600 kg per wheel at a maximum of 70 seconds and a minimum of 0 kg for 105 seconds. The increased temperature is the maximum temperature inside the tire, and the vibration noise is a relative value to Comparative Example 1.
From Table 1, it can be seen that the examples of the present invention significantly reduce vibration noise. Additionally, the incidence of poor adhesion at the edges of the baseband has been significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing a capsule vehicle. FIG. 2 is a sectional view showing a conventional solid tire. FIG. 3 is a sectional view showing an embodiment of the tire of the present invention. 1...Solid tire, 2...Baseband,
3... Adhesive layer, 4... Tread rubber, 5... Tire side surface, 6... Ground contact surface, 7... Concave groove, 8... Convex portion.

Claims (1)

[Claims] 1. A tored rubber composition consisting of a rubber component made by mixing 100 to 75% by weight of natural rubber and 0 to 25% by weight of polybutadiene rubber, and 20 to 60 parts by weight of carbon black with a particle size of 250 to 70 mμ is used as a base. In addition to being vulcanized and bonded to the outer circumferential surface of the band, the contact surface of the tread rubber should be plain with no grooves, and the thickness of the tread rubber should be in the range of 13 to 19% of the outer diameter of the tire. 1. A solid tire for a capsule liner, characterized in that the side surface shape transitions from a concave groove to a convex portion from the end of the baseband toward the tread shoulder in a region adjacent to the tread shoulder.