JPS5855947B2 - Highly durable track belt - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a continuous track belt mainly made of rubber or rubber-like elastic material, which dramatically improves its durability, and has particularly excellent running stability with an excellent anti-rolling function. The aim is to provide this type of endless track belt that has been realized in line with recent improvements.

For a track belt 1 made of general rubber or rubber-like elastic material, the ground plane and its n-n are shown in Figs. 1 and 2, respectively.
The m-plane is shown.

This endless track belt 1 is inside a belt-shaped body 2 made of rubber elastic material.
The core bar 3 is buried at right angles to the direction with the longitudinal spacing thereof reduced, and the strips 4 are embedded parallel to the direction, respectively, at a position where the core bar 3 is surrounded by the strips. This belt-shaped body 2 is usually connected at both ends to form an endless strip, which has a reinforced core made of core bar and strip material, and a grounding lug 5 is provided on the outer circumferential surface of the belt-shaped body 2 when the above-mentioned embedding is performed. molded at the same time.

6 in Figure 1 is the engagement hole of the sprocket wheel.

When the track belt 1 touches the ground under a vehicle load, the wear shown in Fig. 2 (a) occurs mainly on the grounding lugs 5, and the wear shown in Fig. 1 (C) mainly occurs on the skid base. It is important to prevent such cracks, and in this regard, it is desirable to take precautions such as making the entire band 2 made of rubber that is resistant to wear and cracks.

However, since the inner circumferential surface of the endless track belt 1 serves as the surface through which the rolling wheels pass, damage as shown by b in FIG. Therefore, the above measures are not suitable for this case.

On the other hand, both side edges of the endless track belt 1 are provided with grounding lugs 5 during use.
There is a phenomenon in which there is a gap between the ears, that is, an inward deflection d, as shown by the imaginary line in Figure 2, in the middle section of the pipe, and this deflection d is particularly inconvenient when used in wet fields. As a result, the effective ground contact width decreases due to the
Subsidence of '+t' causes damage to turning performance and straight-line performance, and furthermore, the soil scooped up on the inner circumferential surface of the endless track belt 1 is not shaken off and its rolling wheels and guide wheels (not shown) This is because it can get caught in the wheel and cause the train to fall off the track.

For this reason, it becomes necessary to make the core metal 3 larger, especially in the width direction, which results in a disadvantage of increased cost due to the increased thickness of the core metal, and also makes peeling from the rubber more likely to occur.

As can be seen from the above, it has become clear that each rubber part of the endless track belt, which is mainly made of rubber elastic material, is required to perform a special function under different effects.

The present invention was made based on the above findings, and includes core metals spaced apart in the longitudinal direction and perpendicular to the longitudinal direction, and strips parallel to the longitudinal direction. At the position where the material is surrounded by the above-mentioned core metal,
The endless track belt has a reinforcing core consisting of the above-mentioned core metal and strip material and has a grounding lug on its outer circumferential surface. The outer rubber C, which should be located at The inner rubber or the grounding lug is a highly durable endless track band that protrudes into the outer rubber C.

Here, the hardness of the outer rubber C is 45° to 75° JISA, and the hardness of the inner rubber A and the covering rubber A' is 65° to 90°.
The outer rubber C is a rubber with excellent abrasion resistance and crack resistance, and the inner rubber A and the covering rubber A' are rubbers with compression osteoclast resistance and metal resistance. In practice, it is desirable that the rubber has good adhesion.

These rubbers are integrated by vulcanizing and molding each unrefined rubber in a mold to produce an endless belt.

This X is compatible with outer rubber C (l-j: The composition is mainly composed of NR, BR and SBR, with emphasis on wear resistance and crack resistance, and the inner rubber A button and covering rubber A' are The composition is mainly composed of the same <'NR, BR and SBR, but has particularly good compression resistance and suppresses permanent elongation.

The details will be explained below based on the drawings.

Figure 3 shows a fourth example in which the ground contact surface of the endless road belt according to the present invention is removed.
The figure shows the cross section taken along line IV-IV in Figure 3, and
Each figure shows a cross section taken along the line v-■ in FIG. 3.

In the figure, a core bar 11 is embedded inside a band-shaped body 10 of rubber or a rubber-like elastic material at right angles to the longitudinal direction at regular intervals, and after the band-shaped body 10 is made endless. A strip 1 having a winding arrangement that surrounds the core metal 11 from the outer periphery.
2 is also buried, and the structure is the same as that of the conventional structure described above, including the fact that the grounding lug 13 is formed in a raised manner on the outer peripheral surface.

In general, the grounding lugs 13 may be placed almost directly above the core metal 11 as shown in FIG. 3, but they may also be placed in a so-called staggered pattern left and right.

Although any conventionally known core bar 11 can be used, the figure shows a case where a so-called corner 14 core bar 11 is used, which serves as a retaining protrusion. A square mesh hole is formed to fit the sprocket wheel.

The strip 12b is usually a pair of rubber-coated strips 12a and 12b formed by arranging a large number of steel cords.
Arrange in two rows near the outer edge of 1.

These core bar 11 and strip material 12 are collectively referred to as a core body in this specification.

In this invention, the rubber quality of the strip 10 is individually specified in consideration of the performance requirements of each part, and first, as shown in FIG.・
It is divided into an outer rubber C located at the outer rubber C and an inner rubber A that overlaps the outer rubber C on the inner circumferential side.

Here, each rubber material used has the rubber properties described above.

These are the core metal 11. when unvulcanized. l=- and strip 12
They are placed in a predetermined position in the mold, and embedded and combined by vulcanization molding.

To explain the process of this molding, although not shown, two unvulcanized rubber sheets to be used as inner rubber A are placed on a lower mold suitable for forming the inner circumferential surface of the endless track belt. Lay them out in the same direction.

Next, the core bar 11 is placed on top of the core bar 11 and its arrangement determined, and then two unvulcanized rubber sheets, preferably of the same quality as the inner rubber A or the same quality as the covering rubber A' of the strip 12, are placed. Core metal 1
Arrange on top of 1.

Strips 12a and 1 are made of rubber-coated strips 12 made of steel cord on this unvulcanized rubber sheet.
2b is placed under tension.

When this covering rubber A' is rubberized slightly thickly on one side, the arrangement of the unvulcanized rubber sheet of rubber A or A' on the core metal can be omitted.

Finally, one unvulcanized rubber sheet corresponding to the outer rubber C is placed on top of the other.

In this state, place the outer peripheral surface of the track belt on the grounding lug 1.
An upper mold suitable for forming the mold with the above-mentioned lower mold is combined with the lower mold, and while vulcanization molding is performed by heating under pressure, the core bar 1L strip 12 is embedded and combined by vulcanization adhesion, and each rubber is integrated. The rubber elastic material strip 10 is obtained by curing.

Here, the covering rubber A' of the strip 12 is compatible with the inner rubber by being of the same quality, but may have a slightly lower hardness.

During such molding, a local swelling 15 of the high hardness inner rubber A is generated in the low hardness outer rubber C toward the grounding lug as shown in FIG.

In other words, this is due to the difference in softening flow depending on the hardness difference of the rubber materials, but when arranging the unvulcanized rubber sheet of inner rubber A in the lower mold, it is slightly thicker at the position where the grounding lug 13 is to be formed. It is more convenient to prepare in advance, and as the outer rubber C flows into the upper die cavity of the grounding lug 13, the inner rubber A flows together with the flow to form a smooth local protrusion 15.

Of course, the formation of the swollen protrusion 15 is not limited to the above-mentioned method of partially changing the thickness of the unvulcanized rubber sheet of the inner rubber A; Rubber C
Regarding the unvulcanized rubber sheets, the inner rubber A can be set to the outer rubber C at a sufficient height by making use of the volume difference or selecting the desired softening fluidity properties to be applied to both unvulcanized rubber sheets. It is possible to form a local swelling 15 that penetrates into the area.

In the belt-shaped body 10 constituting the endless morning road belt of the present invention, the hardness of the inner rubber A, which is divided into two parts approximately at the center of its thickness, is higher than that of the outer rubber C, and the grounding lug 13 (c) Since the protrusions 15 of the hard inner rubber A are located in the outer rubber C along the protrusions of the lugs, the rigidity in the width direction is also significantly improved as the rigidity in the length direction of the strip 10 is increased. do.

As a result, it is possible to effectively prevent the phenomenon in which the track belt comes off from the rolling wheels, and also to effectively prevent the bending of the ears in wet fields, thereby improving the turning performance and running performance in wet fields. Under the reinforcing effect of the local expansion of the rubber A having high hardness inside the grounding lug 13, deformation of the grounding lug 13 is minimized, which is advantageous for transmitting propulsion force.

As described above, the local swelling 1 caused by the hard inner rubber 10 extending in the width direction at approximately the center in the thickness direction of the band-shaped body
5 does not have the disadvantages of using the f-shaped reinforcing core bar 11, and also contributes to reinforcing the ground lug corresponding to its elongation, thereby realizing prevention of ear bending that is effective in avoiding derailment. Since the inner surface that guides the movement of the wheels is made of hard inner rubber, damage to the rubber is slight, and there is no disadvantage of cracks in the skid base made of outer rubber.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a conventional endless track belt, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, Fig. 3 is a plan view of the endless track belt according to the present invention, and Fig. 4 is Cross-sectional view of line IV-■, No. 5
The figure is a cross-sectional view taken along the line ■-v in FIG. 3. 10...Band-shaped body, 11,12... Core body (
Core metal. strip material), 13... Grounding lug, 15...
- Swelling, A...Inner rubber, A'...Coating rubber, C...Outer rubber.

Claims (1)

[Scope of Claims] 1. A core bar is disposed inside a band-shaped body of rubber or a rubber-like elastic material at right angles to the longitudinal direction, and a strip is disposed parallel to the longitudinal direction. In the endless track belt, which has a reinforcing core consisting of the above-mentioned core metal and strip material, which are embedded and combined at the position surrounding the metal, and which has a grounding lug on its outer circumferential surface, this endless band The outer rubber C, which should be located on the outer periphery side of the core body, is laminated and combined with the covering rubber A' of the strip material and the inner rubber A that wraps the sides and inside of the core metal, and the hardness of each rubber is A highly durable endless track belt in which A≧A'>C, and the inner rubber A protrudes into the outer rubber C toward the grounding lug. 2. In accordance with claim 1, the hardness of the outer rubber C is 45° to 75° JISA, and the hardness of the inner rubber A and the covering rubber A' is 65° to 90° JISA. endless track belt. 3. According to claim 1, the outer rubber C is a rubber with wear resistance and crack resistance, and the inner rubber A and the covering rubber A' have good compression resistance and good liquid temperature properties with metals. Highly durable endless track belt made of rubber.