JPH0579549B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rubber crawler suitably used for a relatively large mobile earth-moving machine.

(Prior Art) Conventionally, the undercarriages of working machines include iron caterpillars a as shown in Fig. 1 (side view) and rubber crawlers b as shown in Fig. 2 (side view). For this purpose, iron crawlers are exclusively used, but in recent years, rubber crawlers have come to be used in the field of relatively small civil engineering work machines.

By the way, it is convenient to be able to install either an iron caterpillar or a rubber crawler as an undercarriage device, but for large civil engineering machines with a machine weight of 8 to 10 tons or more, rubber crawlers for small civil engineering machines are generally used. Since it is not possible to manufacture rubber crawlers with sufficient durability using conventional designs, they are not suitable for use in special cases, such as use on snowy roads or in workplaces where there is little movement. Rubber crawlers for large civil engineering machines have yet to be proposed.

(Problem to be solved by the invention) Conventionally, rubber crawlers for small civil engineering machines have inferior steel properties compared to iron track tracks, so the crawlers tend to come off easily.For this reason, the width of the core metal wings embedded in the main body has been increased. Consideration has been given to increasing the ratio of the core metal embedded part to the non-embedded part to increase rigidity.

However, in large civil engineering machines, the spacing between the sprocket pawls is large, which means that the crawler pitch becomes large. Therefore, if we try to obtain large rigidity by making the core metal wing width sufficiently large, the spacing between the sprocket pawls and the idler windings will be Stress is concentrated in the non-embedded part of the core metal, and the fatigue of the rubber in this part progresses, impairing its durability.

By the way, if the spacing between the sprocket pawls is narrowed, this problem may not be a problem, but replacing the sprocket in order to use the same suspension device as both a steel track pillar and a rubber crawler requires considerable manpower for the replacement work. This is a problem that cannot be implemented because it is necessary.

Regarding the shape of the ground contact side lug of the rubber crawler, the ratio P/M of the ground contact area P of the lug and the machine weight M
There is a relationship in which it is necessary to increase P/M as M becomes larger. For this reason, in applications where the weight of the machine is large, the ratio of the lug area to the total area of the ground contact side of the rubber crawler becomes large, and the shape and arrangement of the lugs must be adequately arranged.

(Means for Solving the Problem) As shown in Figures 1 and 2, the conventional engagement ratio between the crawler pitch and the sprocket pawl is such that the crawler pitch has a ratio of 1 to the sprocket pawl's engagement ratio of 2. However, in the present invention, the engagement ratio is set to 1.
In addition, the core metal is buried in each pitch, and the grounding lug is installed so as to cover almost the entire projected surface of the two circumferentially adjacent core metal wings. The left and right lugs are shifted one pitch back and forth in the circumferential direction.

(Function) The engagement ratio between the crawler pitch and the sprocket pawl is set to 1.
By embedding a core metal in each pitch and narrowing the spacing between the core metals, the rigidity of the crawler body was increased. Also, the grounding lug is
The area covers almost the entire projected surface of the core metal wing, and the left and right lugs are shifted back and forth by 1 pitch, so the part where the crawler body thickness is smaller between the front and rear lugs is the crawler width. This increases the rigidity of the crawler body because it is only on one side and does not span the entire width. In particular, since the lug contact area is large and the rigidity is high, the durability is good and the crawler is less likely to come off.

(Example) Fig. 3 shows an example of a rubber crawler according to the present invention, in which A is a plan view of the contact surface side, and B is a plan view of the contact surface side.
- An X-ray sectional view, and FIG. 4 is a diagram showing its usage state.

Reference numeral 1 denotes a rubber crawler body, and 2 denotes engagement holes formed in the center of the rubber crawler body 1 in the width direction at intervals such that the engagement ratio corresponding to the sprocket pawl is 1:1. Therefore, a core metal 3 is buried between the adjacent engagement holes 2, 2 so that its wing parts 4 are parallel to each other, and a built-up lug 5 is provided on the ground contact side. The lugs 5 are adjacent to each other in the circumferential direction.
The shape is such that it covers almost the entire projected surface of the two core metal wing parts 4, 4, and the left and right lugs 5, 5 are arranged to be shifted back and forth by one pitch.

Fig. 5 shows a lug 5 formed as described above, in which a concave groove 6 is formed in a portion roughly corresponding to between the core metal wing parts 4, 4, and if the rigidity is too high, the depth of the groove can be adjusted as appropriate. Adjustments shall be made accordingly.

FIG. 6 shows still another embodiment, in which a middle lug 7 is provided on the projection surface of the central portion 3a of the core metal 3, which commonly covers the projection surfaces of the left and right lugs 5, 5. , a portion of the left and right lugs 5, 5 are successively connected, which is very effective in increasing the traction force.

(Effects of the Invention) The present invention is configured as described above, and even if it is a rubber crawler for a large civil engineering machine, the crawler pitch is relatively small.
Moreover, since the core metal is embedded in each pitch, the ratio of the core metal embedded dimension F in the crawler circumferential direction to the non-embedded core dimension N (see Fig. 3B), F/N, is
By making it relatively large, even if the F/N is large, the winding around the sprocket wheel 8 and idler 9 is smooth as shown in Fig. 4, and stress concentration on the part where the core metal is not embedded can be avoided. . Therefore, a rubber crawler with high rigidity, less possibility of crawler dislodgement, and good bending resistance can be obtained.

In addition, since the lug 5 has a size that covers the projected surface of the two core metal wings 4, 4, and the left and right lugs are shifted back and forth by one pitch, the rigidity of the crawler body is doubled. Furthermore, by increasing the durability of the lugs, the durability of the crawler itself can be dramatically improved.

In addition, since the core metal engages at each pitch of the sprocket 8, and the left and right lugs 5 are shifted by one pitch, it is possible to prevent the rolling wheels from falling and vibration between the core metals (between the lugs). But it is very good.

[Brief explanation of drawings]

Figures 1 and 2 are side views showing the conventional product;
The figures show the product of the present invention; A is a ground plane side plan view;
B is a cross-sectional view taken along the same line, FIG. 4 is a diagram of the state in which it is used, and FIGS. 5 and 6 are ground-side plan views of other examples. 1...Rubber crawler body, 2...Engagement hole, 3...
... Core metal, 4 ... Wing part, 5 ... Lug, 6 ... Concave groove,
7...middle lug, 8...sprocket wheel.

Claims (1)

[Claims] 1 Engagement holes with sprocket pawls are provided at regular intervals in the center of the width direction of the crawler body, a core metal is buried between the front and rear engagement holes, and a large number of steel cords are installed in the circumferential direction on the ground side of the core metal wing. In rubber crawlers that are buried in a left-right pattern, the lugs on the ground contact side of the crawler body have a shape that is sufficient to almost cover the projected surface of the two adjacent core metal wings, and This rubber crawler is characterized in that it is installed distributed from the center to the left and right, and the left and right lugs are provided at positions shifted by one pitch from the front and back in the circumferential direction.