SU1237800A1 - Apparatus for cutting trees - Google Patents

Description

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The invention relates to forestry machinery and can be used in the forest industry.

The purpose of the invention is to improve performance and simplify the design.

The drawing shows a device for cutting trees, a top view.

The device includes a motor drive 1 of the saw chain 2, the hydraulic motor 3 of the saw tire 4, the oil tank 5, the pump 6, the hydraulic distributor 7, the discharge line 8, the highway 9 of the outlet of the saw tire 4 with the throttle 10 installed in it, the direct valve 11.

The device for cutting trees is mounted on a forest machine 12 by means of a pivoting suspension 13, which is driven by a hydraulic motor 14.

The device works as follows.

After stopping the logging machine 12 and fixing the device for cutting relative to the tree to be cut, the spool valve 7 is turned on. The working fluid from the pump 6 goes through the delivery line 8 to the hydraulic motor 1, which rotates the saw chain 2. Parallel the liquid enters the hydraulic motor 3 by means of which the saw bar 4 is pulled over the tree.

Before sawing, the thrust force of the saw bar 4 is determined by the resistance to rotation of the output shaft of the motor 1 and the pressure in its drain line, and the thrust speed is determined by the throttle cross section 10.

At the time of cutting the saw chain 2 into the tree, the pressure of the working fluid in the injection line 8 of the hydraulic motor 1, respectively, in the thrust cavity of the hydraulic motor 3 increases sharply. Increases and effort: on the engine saw tire 4.

To limit the thrust force of the tire 4, i.e. To reduce the load of the hydraulic motor 1, the delivery pipe 51 of the hydraulic motor 1 and the hydraulic motor 3 is connected to the trunk drain pipe 9 4 through a hydraulic action valve 11 (spring-loaded non-return valve). In the presence of throttles 10 in the line 9, hydraulic valve of direct action 11 under-g

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keeps constant differential pressure in opposite cavities of hydraulic motor 3 saw tire 4. The value of differential pressure is controlled by force

5 valve springs.

With an increase in pressure in the injection line 8 (hydraulic motor load 1), the working fluid overcomes the resistance of the valve spring 11 and

10 pressure at its outlet, is poured into the line 9 and creates a back pressure in the retraction cavity of the hydraulic motor 3, thereby limiting the force and speed of pulling the saw bar 4.

15 The size of the flow area of the throttles 10 is constant and is selected, based on the maximum allowable, in terms of the strength of the parts of the device, the speed of the idle thrust of the saw tire 4 and its retraction at the end of sawing.

In the process of sawing, there is some unproductive consumption of the working fluid flowing from the 25 oppression line 8 through the valve 11 and the throttle 10 to the drain. The magnitude of the loss of power of the hydraulic motor 1 depends on the living areas of the piston of the hydraulic engine 3 and its stroke,

30, therefore, the use of a hydraulic engine 3 of small size and the corresponding throttle 10 allows in line 9 to create a low backpressure at which the loss

The power of hydraulic motor 1 becomes dim.

In practice, this loss is less than 2% and does not exceed the loss of the most economical hydraulic actuators,

40 commercially available loggers for cutting equipment - Hbtx machines.

However, the connection of the injection line 8 with the highway 9

45 of the tire retraction through the direct action valve 11 in the area between the hydraulic motor 3 and the throttle 10 makes it possible to avoid repeating the sawing operation with insufficiently accurate

jQ installation of the device relative to the tree to be cut, as well as when cutting large-sized trees, when, the range of the saw bar D. is limited by the angle oi of its

the gate is insufficient.

In such cases, it is possible to increase the area of saw blade 4 and continue sawing.

the gate is insufficient.

In such cases, it is possible to increase the area of saw blade 4 and continue sawing.

those. turn on the hydraulic motor 14 of the rotary suspension 13 without turning off the hydraulic motor 1. When the suspension 13 turns to the angle f in the sawing process, the pressure difference in the cavity of the hydraulic motor 3 remains the same, even if its piston moves in the opposite direction. Since in this case the thrust force of the saw bar 4 remains the same, the overload

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and the motor 1 does not stop,

The use of the proposed tree-cutting device makes it possible to exclude a simple machine due to the malfunction of its hydraulic system, reduce the total time spent on cutting trees, greatly simplify the design and improve the working conditions of the operator-operator.

Editor I. Segl Nick

Order 3270/36 Circulation 610 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Z-ZZ, Raushsk nab., d, 4/5

Production and printing company, Uzhgorod, ul, Proektna, 4

Compiled by Y.Tazov Tehred L.Oleinik

Proofreader M. Pojo

Claims (1)

CUTTING DEVICE · TREES installed by means of a rotary suspension on a forest machine and including a saw bar with a saw chain, a hydraulic motor for feeding the saw tire, a hydraulic motor for driving the saw chain, having a common discharge line, and a throttle device installed in the busbar that, in order to improve performance and simplify the design, the injection pipe is connected to the bus pipe through a direct-acting relief valve in the area ezhdu throttling device and the hydraulic motor.