JPS6310257B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an excavator for excavating earth and sand, and more particularly to an excavator suitable for digging trenches where there are underground objects such as cables, water pipes, gas pipes, etc.

When laying cables, various types of piping, etc. underground, it is necessary to dig a trench along the installation route. Usually, this installation route is provided along the road, but especially in urban areas, it is common for various underground structures to be provided below the road. When digging a trench to install a new cable or the like in such a location, care must be taken not to damage existing underground structures. It is efficient to use excavators such as backhoes and trenchers to dig trenches, but when such excavators are used, there is a risk of damaging underground objects when the excavation mechanism hits them. There is a possibility that Therefore, in urban areas where there are many underground objects, road paving materials are removed and excavation is carried out mechanically to a certain depth, but excavation deeper than that is done manually while paying attention to underground objects. I'm walking along. For this reason, excavation work is extremely inefficient.

In order to efficiently carry out excavation work, the present applicant has proposed an excavator that excavates earth and sand using an elastic rotary cutter such as a wire hole or a hard rubber cylinder having a large number of protrusions. The rotary cutter of this excavator has elasticity, so even if it hits an underground object, it will not damage it, but the truck moves forward and backward repeatedly to check for the presence of underground objects as it moves forward. Therefore, the disadvantage is that the excavation speed is slow and workability is low.

SUMMARY OF THE INVENTION An object of the present invention is to provide an excavator that does not damage underground objects even when it hits them, and can increase excavation speed.

Embodiments of the present invention will be described in detail with reference to the drawings. FIGS. 1 and 2 show an excavator 10 according to the present invention.
This excavator includes a truck 12, an excavation mechanism 14 mounted on the truck, and a drive means (not shown) that drives the excavation mechanism in the vertical direction.

The excavation mechanism 14 is supported by supports 16,1 on the truck 12.
A support arm 20 attached to a slider 18 that slides up and down while being guided by a support arm 2
It consists of a plurality of excavating blades 22 attached to the lower end of the excavator 0 in a row in the horizontal direction. Therefore, when the drive means is driven, the support arm 20 moves vertically with respect to the soil to be excavated, so that the excavation blade 22 scrapes up the soil. Since the truck 12 moves forward each time the excavator blade 22 makes one reciprocating motion, a groove 26 is formed in the road 24 as shown in FIGS. 1 and 2.

As shown in FIGS. 3 to 5, each excavation blade 22 is provided with a fixed blade 28 integrally fixed to the lower end of the support arm 20, and a fixed blade 28 that is overlapped with the lower end of the fixed blade. The movable blade 32 is pivotally supported at the lower end of the blade. In the illustrated embodiment, all fixed blades 28 consist of one horizontal end 20a extending horizontally from the lower end of the support arm and a plurality of carbide tips 28a independently attached to the front end of this horizontal end. However, they may be separated like forks. The movable blade 32 is normally connected to a spring biasing means 34 which is spring biased so as to overlap the lower surface of the fixed blade 28, and this spring biasing means 34 is connected to a bracket 36 attached to the support arm 20 and each movable blade. It consists of an extension spring 38 suspended between 32 and 32. In addition, each extension spring 38
passes through a hole 20b in the horizontal end 20a of the support arm. As can be seen from FIG. 4, each movable blade 32
protrudes more than the fixed blade 28, and normally, when the excavation blade 22 rises, only the movable blade 32 bites into the earth and sand to be excavated.

Next, describing the usage state of the excavator 10 of the present invention, as shown in FIGS. 1 and 2, the excavation mechanism 1
The excavator 10 carrying the excavator 4 is intermittently moved forward on the road 24 to be excavated, and the excavating mechanism 14 is vertically moved to excavate the road. In this case, the forward pitch of the excavator 10 is set to be equal to or less than the length of the protruding portion of the movable blade 32. In this case, normally the movable blade 32 as shown in FIG.
The earth and sand are scraped up by the machine, but when it hits an object 40 (see Fig. 6) that is not buried underground, such as a stone, one or a small number of movable blades 32 resist the tensile force of the extension spring 38. It pivots downward around axis 30 and escapes. If the movable blade escapes by one or a few times, it means that the object hit is not a long one, so after that excavation, the cart should be moved one more time.
Move forward one step at a time. Then, in the next excavation, the fixed blade 28 hits a buried object such as a stone and lifts it up, so that the earth and sand can be excavated without any trouble. However, when the digging blade 22 hits a long underground object such as a cable, water pipe, or gas pipe, all or most of the movable blades 32 escape at once.
Therefore, when all or most of the movable blades have retreated, the operator determines that he has hit a long underground object, stops digging, and excavates only that part manually, avoiding the underground object. .

As shown in FIG. 6, a limit switch 42 attached to the support arm 20 is provided corresponding to the spring biasing means 34 of each movable blade 32, so that when the limit switch 42 is pressed by the extension spring 38, By lighting lamps provided on the driver's seat panel corresponding to each movable blade, it is possible to indirectly monitor the retreat of the movable blade from the driver's seat without having to directly monitor the movable blade.

According to the present invention, as described above, even if the excavation blade collides with an underground object, the underground object is not damaged due to the retreat of the movable blade, and even if all of the plurality of movable blades are retreated. It is easy to judge whether the object is underground or not based on whether one part has retreated, and there is no need to move the cart back to confirm the existence of underground objects, which greatly improves excavation speed. Able to work efficiently.

[Brief explanation of the drawing]

1 and 2 are a front view and a side view of an excavator according to the present invention, FIGS. 3 to 5 are an enlarged top view, side view, and rear view of main parts of the present invention, and FIG. 6 is an enlarged view of the main part of the present invention. FIG. 6 is a side view of another embodiment of the invention in an operating state; DESCRIPTION OF SYMBOLS 10... Excavator, 12... Dolly, 14... Excavation mechanism, 20... Support arm, 22... Excavation blade, 2
4...Road, 26...Groove, 28...Fixed blade, 30
... Pivot, 32 ... Movable blade, 34 ... Spring biasing means, 38 ... Extension spring.

Claims (1)

[Claims] 1. An excavation mechanism that includes a truck, a support arm that is mounted on the truck and moves up and down relative to the soil to be excavated, and a plurality of excavation blades that are attached to the lower end of the support arm in a row in a horizontal direction; In the excavator, each of the excavating blades is provided with a fixed blade fixed substantially perpendicularly to the lower end of the support arm, and a fixed blade superimposed below the fixed blade so as to separate from the fixed blade. a movable blade which is pivotable to the fixed blade, said movable blade being connected to spring biasing means which is normally spring biased to overlap the lower surface of said fixed blade; An excavator characterized in that the fixed blade protrudes from the fixed blade at a position where the fixed blade overlaps with the fixed blade.