Protection device for hydraulic actuator of front loader

FIELD: construction, pipeline.

SUBSTANCE: invention pertains to hydraulic actuators of carrying and lifting machines, namely, to front loaders handling supplies and construction materials in the scoop on construction sites and off-the-road. Protection device of the hydraulic actuator of a front loader contains a heavy hauler, working equipment, boom hydraulic cylinders and, at least, one balancing cylinder, head end whereof is connected with a gas cylinder. Accumulator, reverse-flow valve and an adjustable choke are switched to the head ends of the boom hydraulic cylinders. Valve "OR" is installed into the hydraulic line connecting distribution unit with rod ends of the boom hydraulic cylinders.

EFFECT: protection of hydraulic actuator from the negative effect as on working equipment lifting - down casting as in wheels movement over abrupt supporting surface.

4 dwg

 

The invention relates to a hydraulic lifting-transport machines, namely, frontal loaders, engaged in the movement of goods and construction materials in the bucket in terms of construction sites and off-road.

Known protection device hydraulic front loader that includes live axle with wheels, suspension bridge, containing the cylinders of the suspension, hydropneumatic accumulator, check valve and adjustable chokes, pressure relief valve [see, for example self-Propelled wheeled earthmovers /Ulyanov N.A., Roninson EG, V.G. Soloviev - M.: Mashinostroenie, 1976. - 359 S.].

A disadvantage of this device is the design complexity, due to the fact that the protection system use additional hydraulic cylinders, which increases the cost of the system.

Known hydraulic operating equipment front loader [see, for example, patent 2280737 C2, IPC E02F, 2006.01], which includes a wheeled tractor, working equipment, hydraulic cylinders boom and balancing pneumatic cylinder, a piston chamber which is connected to a gas cylinder, a relief valve.

A disadvantage of this device is the lack of protection of the hydraulic drive from disturbing influences when lifting, lowering work equipment when driving on an uneven support surface.

<> The objective of the invention is to protect the hydraulic actuator as from impacts when lifting, lowering work equipment and the movement of the wheels on the uneven support surface.

The task of the invention is solved due to the fact that in the known device, containing the tractor, working equipment, hydraulic cylinders boom and at least one balancing cylinder, a piston chamber which is connected to the gas cylinder according to the invention in a piston cavity of the hydraulic cylinders boom connected the battery, check valve and an adjustable throttle, hydroline connecting the dispenser rod cavities of the hydraulic cylinders boom, installed valve "OR".

The invention is illustrated by drawings, where figure 1 shows a front loader with the highest elevated work equipment, provided with a device for protection of the hydraulic actuator; figure 2 - front-end loader with working equipment at maximum boom equipped with a protection device of the hydraulic actuator; figure 3 presents the system of protection of working equipment with two hydraulic cylinders boom and one of the balancing cylinder; 4 - the system of protection of working equipment with one cylinder arrows and two balanced pneumatic cylinders.

The protection device hydraulic front shipped is of OPIC contains wheeled tractor 1, working equipment 2, the cylinders of the boom 3, a counterbalancing pneumatic cylinder 4, the gas cylinder 5, a battery 6, the check valve 7, an adjustable orifice 8, the valve OR 9, the valve 10, the hydraulic pump 11, the pressure relief valves 12, 13, the tank 14.

The essence of the protection of the hydraulic front loader from effects is to expand the functionality of the invention in different modes of operation front loader: acceleration and braking of work equipment when lifting, lowering, work truck in transport mode when driving on uneven supporting surface.

The essence of the operation of the invention in the mode of the rise of a working equipment after filling the bucket with material consists in the operation of the acceleration of the working equipment of the stationary state in the mode of lifting, in which there are large forces of inertia and increases the pressure of the working fluid in the piston cavities of the hydraulic cylinders boom, which results in the discharge of a small amount of fluid in the battery. After the dispersal of the working equipment comes the steady state rotation arrows disappear forces of inertia and decreases the pressure in the piston cavities of the hydraulic cylinders boom. During this period, an overflow of the small volume of the working fluid from the accumulator back into hydrocele the other arrows.

The essence of the transport mode of the invention consists in the following. The movement of a front loader with a load in the bucket happens with the boom raised to the intermediate position shown in figure 2. When the wheels of the truck to some irregularities with the length l and height h, the operator with the existing hydraulic system work equipment usually reduces the speed or performs maneuvers to bypass irregularities. In both considered cases decreases the performance of the truck. The proposed method allows to move the bumps without slowing down the movement of the machinery. The essence of the operation of the device in transport mode is as follows. Hitting the wheels of the truck on the irregularity occurs at the time

where V- the speed of movement of the tractor with a load in the bucket.

For time t1is turning frame of the tractor about the axis of the rear axle together with the working and experiencing the acceleration of the boom and load, resulting in the piston cavities of the hydraulic cylinders boom increases the pressure of the working fluid. When a pressure accumulator is reset small amount of fluid from the piston cavities of the hydraulic cylinders boom in the battery 6 (3, 4). When lowering the wheels of the truck with irregularities happens is throttling the working fluid when returning it from the battery 6 in the working cavity of the hydraulic cylinders boom. This limits the pressure in the hydraulic cylinders boom and subsequent quenching of the oscillations. The movement of the forklift with the load in the bucket is at a high transport speed and provides high performance machines.

The protection devices of the hydraulic operating equipment for acceleration of work equipment is as follows. To lift the bucket of the loader, after completing his material, carry out the inclusion of the slide valve of the distributor 10 down. The working fluid from the hydraulic pump 11 is served in the piston cavity of the hydraulic cylinders 3 arrows. The beginning of the rise of the working equipment is accompanied by a considerable force of inertia of the working equipment and the increase in the pressure in the cavities of the hydraulic cylinders boom, causing part of the liquid is discharged through the check valve 7 in the battery 6. After the dispersal of the working equipment and the establishment of a constant speed of rotation of boom pressure in the working spaces of the cylinders of the boom is reduced and the working fluid from the battery 6 through an adjustable throttle piston 8 is returned to the cavity of the hydraulic cylinders 3 arrows. At the same time when a decrease in the volume of the piston cavities of the hydraulic cylinders 3 arrows is a corresponding increase in the rod ends of these cylinders are provided with valve "OR" 9, ensure the suction of the working fluid from the tank 14 to the rod end of the hydraulic cylinders boom. When returning the working fluid from the battery 6 to the cylinders 3 volume piston cavities increases, and the volume of the rod ends is reduced due to message the rod ends of the cylinders 3 arrows with discharge to the tank through the valve "OR" 9.

The operation of the device in transport mode is as follows. When hitting the wheels on the roughness of the support surface is rotated frame of the truck relative to the axis of the rear axle and there is a force of inertia of the working equipment, and increases the pressure in the piston cavities of the hydraulic cylinders 3 arrows. As a result, the portion of the volume of the working fluid is discharged from the piston cavities of the hydraulic cylinders 3 arrows in the battery 6. After moving irregularities in the working fluid from the battery 6 is returned through a managed hydrotussin 8 in the piston cavity of the hydraulic cylinders 3 arrows. At the first phase of operation of the device, the working fluid through the valve "OR" 9 sucked into the rod end of the cylinders 3 arrows from the tank, and the second phase of the process the working fluid displaced from the rod ends of the cylinders 3 arrows in the tank through the valve "OR" 9.

The proposed invention in the mode of lifting-lowering work equipment the study is carried out as follows. For lifting work equipment valve dispenser 10 include down. The working fluid from the hydraulic pump 11 is served in the piston cavity of the hydraulic cylinders 3 arrows. Thus from the rod ends of the cylinders 3 arrows working fluid through the valve OR 10 is discharged into the tank 14. To perform the operation of lowering work equipment valve dispenser 10 include up. The working fluid from the hydraulic pump 11 is fed through a valve OR piston 9 in the cavity of the hydraulic cylinders 3 arrows from the piston cavities of these cylinders, the working fluid is discharged into the tank 14 through the valve 10.

When performing lifting, lowering pressure and load balancing hydraulic cylinders 4 are virtually unchanged due to the size of the gas cylinder 5.

The protection device hydraulic front loader containing the tractor, working equipment, hydraulic cylinders boom and at least one balancing cylinder, a piston chamber which is connected to a gas cylinder, wherein the piston cavities of the hydraulic cylinders boom connected the battery, check valve and adjustable throttle and hydroline connecting the dispenser rod cavities of the hydraulic cylinders boom, installed valve "OR".



 

Same patents:

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6 dwg

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7 cl, 1 dwg

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4 dwg

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1 dwg

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3 dwg

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9 dwg

FIELD: mechanical engineering.

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5 cl, 6 dwg

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EFFECT: increased simplicity and efficiency of hydraulic drive heating at negative ambient temperatures.

1 dwg

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