JPH0638922Y2 - Front frame of wheeled loader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a so-called articulated wheeled loader in which a front part and a rear part of a vehicle are separated and connected to each other. In particular, the present invention relates to an improvement of the front frame that constitutes the front part of this wheeled loader.

[Conventional technology]

FIG. 3 is a conceptual side view showing a general wheeled loader 1.

The wheeled loader 1 is a so-called articulated wheeled loader, and comprises a separated front frame 2 forming a main part of a vehicle front part and a separated rear frame 3 forming a main part of a vehicle rear part. The front frame 2 and the rear frame 3 are configured as shown in FIG.
As shown in FIG. 4 shown in the AA sectional view, they are connected by a center hinge portion 4.

In FIG. 3, reference numerals 4 and 5 denote front wheels and rear wheels of the wheeled loader 1, and reference numerals 6, 7, 8, and 9 denote buckets, booms, bucket cylinders, and booms of the wheeled loader 1, respectively. Shows a cylinder. In addition, reference numeral 10 in FIG.
Is a steering cylinder, 11 is a steering cylinder 10
Shows the pivot.

Next, the conventional front frame 2 of the wheeled loader 1 described above will be described in detail.

FIG. 5 is a conceptual perspective view showing a conventional front frame 2. The front frame 2 is mounted on the lower frame 20 constituting the lower part of the front frame 2 and the upper part of the lower frame 20, and various bearing holes are provided. And an upper frame 21 formed with.

Of these, the lower frame 20 is composed of a front plate 22 that covers the front of the front frame 2 and a pair of side plates 23 that covers the front side of the front frame 2, and the upper frame 21 is a top plate 24 that covers the upper front part of the front frame 2. And a pair of side plates 25, which are separate members arranged on both sides of the upper part of the side plate 23. The pair of side plates 25 are welded laterally to the side plate 23 through the ribs 26 for reinforcement and are fixed thereto.

In FIG. 5, reference numeral 30 is a pair of boom pivots formed on the side plate 23 and side plate 25, 31 is a pair of boom cylinder pivots formed on the side plate 25, and 32 is formed in the center of the upper plate 24. It is a bucket cylinder pivot.

[Problems to be solved by the device]

By the way, in the above-mentioned front frame 2, the front wheels 4
The axle mount portion 33, the boom mount portion 34, and the bucket cylinder mount portion 35 that support (Fig. 3) receive an external force, so that these members are able to withstand the external force. , The side plate 23 and the center hinge 4 (FIG. 4) are welded together, but in addition, the side plate 25, which is a separate member in which the boom pivot 30 and the boom cylinder pivot 31 are formed, is also provided with a rib 26 for reinforcement. It is joined to the side plate 23 by welding through. Therefore, in the conventional structure of the front frame 2, the number of parts and the number of welded parts are so large that the number of assembling steps is increased, which results in a low assembling work efficiency and a high manufacturing cost.

On the other hand, in the front frame 2, the centering accuracy of each pivot, especially the pair of left and right boom pivots 30 and the pair of left and right boom cylinder pivots 31, must be improved from the viewpoint of improving the reliability and durability of the wheel loader 1. However, conventionally, the pair of left and right boom pivots 30 and the pair of left and right boom cylinder pivots 31 described above are formed on the pair of side plates 25, which are separate members, respectively, and when welding, a hole for the pivot is formed in advance. Since the pair of side plates 25 thus positioned are respectively positioned at predetermined positions, and then the welding work is performed,
Due to the difficulty of positioning accuracy of each side plate 25 during welding and the expansion and contraction when the deposited metal is solidified, the centering accuracy of each pivot is lowered.

In view of the above-mentioned problems, the present invention reduces the number of parts and welding points of the upper frame forming the upper part of the front frame, and improves the centering accuracy of the pivot hole formed in the upper frame. It is intended to provide a ftunt frame of.

[Means and Actions for Solving the Problems]

In order to achieve the above-mentioned object, in the present invention, the upper frame constituting the upper part of the front frame is provided with at least a plate thickness more than that of other components constituting the front frame in which the bucket cylinder pivot and the boom pivot are arranged. A thick and strong single plate and a boom cylinder pivot are formed, and configured by a pair of plate-shaped boom cylinder pivot members connected to both ends of the single plate,
With this, the upper frame that constitutes the upper part of the front frame is unitized, and simply place the upper frame of the unitized front frame on the lower frame that constitutes the lower part of the front frame and weld it. The front frame is assembled by.

〔Example〕

Hereinafter, an embodiment of the front frame according to the present invention will be described in detail.

FIG. 1 is a conceptual perspective view of an upper frame 40 constituting an upper portion of a front frame according to the present invention, and the same portions as those in FIG. 5 are designated by the same reference numerals.

The upper frame 40 is a solid single plate that is at least thicker than the other components of the front frame described later.
41 and a pair of boom cylinder pivot members 42 disposed below both ends of the single plate 41, and the number of parts constituting the upper frame is extremely large as compared with the conventional example (FIG. 5). There are few. The boom cylinder pivot member 42 is made of a plate material having an L-shaped cross section, and the boom cylinder pivot member 42 is welded or integrally cast to the single plate 41.
It is formed integrally with.

According to such a structure of the upper frame 40, when the upper frame 40 is machined or attached to the lower frame described later, the entire kappa frame 40 can be handled as one unit (unit). .

On the other hand, a pair of brackets 43 on which the bucket cylinder pivot 32 is processed and formed are fixed to the single plate 41 by welding or integral casting in the center of the upper surface 41a of the single plate 41. A pair of brackets 44 on which the boom pivot 30 is formed are fixed to the one plate 41 by welding or integral casting on both ends 41b and 41c of the upper surface 41a.

According to the unitized upper frame 40, a pivot hole is integrally formed from the side of the brackets 43, 44 and the boom cylinder pivot member 42 by a drilling jig such as a drilling machine (not shown). Therefore, the bucket cylinder pivot 32 with high centering accuracy is formed on the pair of brackets 43, and the boom pivots 30 with high centering accuracy are further mounted on the brackets 44 arranged in pairs. The boom cylinder pivots 31 having a high height are formed on the pair of boom cylinder pivot members 42, respectively. Therefore, when a pivoting center shaft of a boom or a cylinder (not shown) is fitted into each pivot, the centering accuracy of each pivot is high, so that one edge of the pivoting center shaft of each pivot, boom, cylinder, etc. Is less likely to occur, which significantly improves the accuracy and durability of the wheel loader.

In this way each pivot (bucket cylinder pivot 32,
Boom pivot 30 and boom cylinder pivot 31) are integrally drilled to form a unitized upper frame 40.
Is attached to the upper part of the lower frame 20 of the front frame 50 according to the present invention shown in FIG. 2 in which the same parts as those in FIG. 5 are designated by the same reference numerals, and the contact portion between the lower frame 20 and the upper frame 40, that is, the arrow B, When welding is performed at a total of four portions including the portion on the other side, which includes the portion on the other side that faces the C, the lower frame 20 and the upper frame 40 that form the front frame 50
And are firmly fixed, and the entire front frame 50 is assembled. Therefore, in the embodiment, the front frame 50
The number of parts and welding points are extremely small for the assembly of
Therefore, the number of assembling steps is reduced as compared with the conventional example.

In FIG. 2, reference numeral 23a is a step portion formed above the side plate 23 that constitutes the lower frame 20, and this step portion 23a is the end portions 41b and 41c of the single plate 41 that constitutes the upper frame 40. The single plate 41 is engaged and positioned on the lower frame 20.

[Effect of device]

As described above, in the front frame according to the present invention, the number of parts of the upper frame that constitutes the upper portion of the front frame is reduced, so that the number of welding points when assembling the entire front frame is reduced, and the upper frame is a single plate. Since it is unitized on the basis of, it is possible to integrally process the pivot holes, and thus it is possible to obtain a wheeled loader that has high centering accuracy of each pivot, is inexpensive, and has high reliability and durability.

[Brief description of drawings]

FIG. 1 is a conceptual perspective view of an upper frame constituting an upper portion of a front frame according to the present invention, FIG. 2 is a conceptual perspective view of a front frame according to the present invention, and FIG. 3 is a conceptual side view of a wheeled loader. FIG. 4 is a sectional view taken along the line AA in FIG. 3, and FIG. 5 is a conceptual perspective view showing a conventional front frame. 1 ... Wheeled loader, 4 ... Front wheel, 20 ... Lower frame, 30 ... Boom pivot, 31 ... Boom cylinder pivot, 32 ... Bucket cylinder pivot, 40 ... Upper frame, 41 ... One piece Plate, 42 ... Boom cylinder pivot member.

Claims (3)

[Scope of utility model registration request] 1. A lower frame supporting a front wheel, and a bucket cylinder pivot fixedly mounted on the lower frame,
In a front frame of a wheeled loader having a boom pivot and an upper frame on which a boom cylinder pivot is formed, the upper frame includes a single plate on which the bucket cylinder pivot and the boom pivot are formed, and the single plate. And a pair of boom cylinder pivot members formed with the boom cylinder pivot, the front frame of the wheeled loader. 2. The wheeled loader according to claim 1, wherein the one plate has a plate thickness at least larger than that of other constituent parts of the front frame. Front frame. 3. The boom cylinder pivot portion has a substantially L-shaped cross section.
The front frame of a wheeled loader according to claim (1), characterized in that it is a letter-shaped plate material.