JPS6130881Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a suspension for a dual-axle vehicle.

The suspension of two rear axles in a multi-axle vehicle such as a two-axle rear wheel vehicle is generally designed based on a loaded state, so the spring constant when the vehicle is empty is large, making the ride uncomfortable. This tendency was particularly strong in vehicles such as tractors and snowplows, which have a large difference in the spring load of the suspension when the vehicle is empty, or vehicles with a short wheelbase.

The present invention was devised in view of the drawbacks of the conventional structure. Three or more leaf springs with different longitudinal lengths are rotatably supported on the vehicle body frame as a suspension for the front and rear axles, and are connected at the center. The purpose of the present invention is to provide a suspension that improves riding comfort and running stability by increasing the spring constant in stages according to the increase in the load due to the structure in which the suspension is installed with a gap between the top and bottom, except for the upper and lower parts. .

The present invention will be explained in detail below based on illustrated embodiments.

In FIGS. 1 and 2 showing one embodiment, the suspensions of a front axle 1 and a rear axle 2 of a multi-axle vehicle are constructed as follows. A trunnion shaft 5 is fixed to the vehicle body frame 3 via a bracket 4 at an intermediate position between both shafts 1 and 2, and a shaft cover 6 is attached to the spring seat 7, which is fitted into the shaft 5 so as to freely slide and rotate. and secure it. A plurality of leaf springs are superimposed and attached on the spring seat 7 as described later. The lowermost leaf spring 9 has a two-plate structure, and the central part is fixed onto the spring seat 7 by directly overlapping with bolts and nuts to be described later, and a gap is provided between the top and bottom on both sides. By fastening the parts with the clip band 10, both ends are tied together.
Pressure-fits between plates so that they can slide freely.

Then, both ends of the leaf spring 9 are slidably pressed onto the axle pads 11 and 12 fixed on the front axle 1 and the rear axle 2. Also, by fixing hook-shaped spring hangers 13 and 14 integrally with each axle pad 11 and 12 with a gap between both ends of the leaf spring 9,
Mainly when axles 1 and 2 rebound, axle 1,
This restricts the upward movement of 2 and provides good operating characteristics.

Further, a leaf spring 16 is superposed on the center portion of the leaf spring 9 via a spacer 15, and a leaf spring 18 is superposed on the center portion of the leaf spring 9 via a spacer 17.
After polymerizing 9, bolts 20, 21 and nut 2
2 and 23 on the spring seat 7.

Here, the leaf springs 9, 16, 18 are formed so that their front and back lengths become shorter in order from the lower side to the upper side, and the spacers 15, 17
By adjusting the thickness of each leaf spring, appropriate gaps a and b are provided between the upper and lower parts over the entire length of each leaf spring except for the central part. Also, the top leaf spring 18
and the lower leaf spring 9 are fastened together with clip bands 10, 24 to restrict lateral displacement of these springs.

In a suspension having such a configuration, when the vehicle is empty, the leaf springs 16,
18, the vehicle body load is supported on both axles 1 and 2 only by the lowest leaf spring 9, which is not in contact with 18.
A soft spring constant can be obtained. Furthermore, when the vehicle is loaded, the vehicle body descends due to an increase in the load, and when both ends of the intermediate leaf spring 16 come into contact with the lower leaf spring 16, the two leaf springs 9,
16 work together to support the vehicle body load, the spring constant increases, and as the load increases further, both ends of the uppermost leaf spring 18 also come into contact with the middle leaf spring 16, and all the leaf springs 9, 16 and 18 are actuated, the spring constant further increases.

In this way, each leaf spring 9, 16, 18 is installed with gaps a and b between the top and bottom, respectively, so that the spring constant A of the suspension gradually increases in three stages as the load increases, as shown in Figure 2. Therefore, compared to the linear spring constant B of the conventional structure in which multiple leaf springs are overlapped without gaps, it is possible to make the ride more comfortable when the vehicle is empty and when the load is light, and it also improves running stability. It is possible to make it good.

Furthermore, when the vehicle is running on an uneven road surface, the suspension swings around the trunnion shaft 5, and the contact area between the lowest leaf spring 9 and the axle pads 11, 12, and between each leaf spring 9, 16, 18. The front axle 1 and the rear axle 2 move independently in the vertical direction as the contact portion of the axle pad 1 slides in the longitudinal direction, and the spring constant of the axle pad 1
Similar to the conventional trunnion suspension structure, the shape of the contact portions 1 and 12 with the springs 9 gradually changes to provide good riding comfort.

As explained above, according to the present invention, the spring constant of the suspension increases in stages as the carrying load increases, so that the ride comfort and running stability of the vehicle can be improved.

[Brief explanation of the drawing]

Figure 1A is a side view of essential parts showing an embodiment of the present invention, Figure B is a view taken in the - direction arrow of Figure A, and Figure 2 compares the suspension characteristics of the above embodiment and a conventional example. This is the graph shown. 1...Front axle, 2...Rear axle, 3...Vehicle frame, 5...Trunion shaft, 9, 16, 18
... Leaf spring, 11, 12 ... Axle pad, 15, 17 ... Spacer, a, b ... Gap.

Claims (1)

[Scope of utility model registration request] Three or more leaf springs whose front and back lengths are sequentially longer from top to bottom are connected together at the center, and the center portion is pivotally supported to the vehicle body frame for free swinging, and the center portion of each of the leaf springs is The structure is such that there is a gap between the top and bottom, and both ends of the bottom leaf spring are supported on the front and rear axles so that they can freely slide in the front and rear axles. A suspension for a multi-axle vehicle characterized by a spring constant that changes stepwise each time both ends of a leaf spring come into contact with a lower leaf spring.