RU2236515C1 - Boom machine working equipment gravity force balancing device - Google Patents

Abstract

FIELD: boom, earth-moving, mine and other cyclic-action lifting and transportation machines.

SUBSTANCE: proposed gravity force balancing device of working equipment has at least one main and one balancing cylinders and at least one gas bottle and one working liquid distributor. Piston space of balancing cylinder is connected with gas bottle. At least one balancing cylinder is located inside gas bottle coaxially with the latter.

EFFECT: improved efficiency and reliability of machine.

2 cl, 6 dwg

Description

The invention relates to boom digging, mining and other hoisting-and-transport machines of cyclic action.

A device for balancing the gravity of the working equipment of a boom machine [1], comprising converting the potential energy of the gravity of the working equipment to the potential energy of compressed gas in a pneumatic accumulator when lowering the boom and the use of this energy when lifting the boom, containing the main and balancing hydraulic cylinders, pneumatic accumulator, main and additional distributors.

However, the known device has the following disadvantages: it has a complex structure and low efficiency due to the use of a pneumatic accumulator, an additional distributor and a hydraulic line, which reduce the efficiency of the balancing device.

Of the known technical solutions, the closest in technical essence to the claimed object is a device for balancing the gravity of the working equipment of the boom machine [2], containing working equipment, the main and balancing cylinders, the main and additional valves, a pneumohydroaccumulator with gas cylinders, a device for compensating leaks of working fluid, hydraulic lines.

The disadvantages of the device are the use of a working fluid with a significant viscosity as a balancing body, and the complex design of the device, containing a pneumohydroaccumulator, a compensation device, and extended hydraulic lines.

According to the physical nature of the processes being implemented, the device [2], as well as the device [1], are energy recovery devices in which, when lowering the working equipment, the potential energy of the gravity of the working equipment is converted into potential gas compression energy in a pneumatic accumulator. The energy of compressed gas during lifting is used to overcome the gravity of the working equipment. However, these transformations are not ideal, but are associated with the need to transport in each working cycle of raising and lowering the working equipment of the appropriate volume of working fluid from the balancing cylinder to the pneumatic accumulator and vice versa, which are accompanied by energy losses due to the friction of the working fluid in the pipelines and an additional distributor.

The objective of the invention is to provide a device for balancing the gravity of the working equipment, which can significantly increase the efficiency of the machine by eliminating energy losses to overcome the gravity of the working equipment during the process, to increase the reliability of the system and overall efficiency.

The problem is solved due to the fact that in the known device, including working equipment and at least one main and one balancing cylinder and at least one distributor of working fluid and a gas cylinder, according to the invention, the piston cavity of the balancing cylinder is connected to a gas at the same time, at least one balancing cylinder can be located inside the gas cylinder and aligned with it.

The connection of the piston cavity of the balancing cylinder with a gas cylinder makes it possible to use gas as a balancing body and solve the problem of balancing the gravity of the working equipment, while the operations of converting the potential energy of the gravity of the working equipment to gas compression energy and the inverse transformation are eliminated and energy losses associated with transportation are eliminated working fluid in the lines between the balancing hydraulic cylinder and the pneumatic accumulator at each lift and uskanii working equipment. In the proposed device according to the invention, the piston cavity of the balancing cylinder is connected to a gas cylinder.

The invention is illustrated by drawings, where in Fig.1 shows a General view of the excavator with a balancing device consisting of two cylinders (balancing and main); figure 2 shows a General view of the excavator with a balancing device containing three cylinders (balancing and main); figure 3 is a hydraulic diagram of a device for balancing gravity with an autonomous gas cylinder; figure 4 is a hydraulic diagram of a device for balancing gravity with an autonomous gas cylinder and an additional distributor in the stock hydraulic lines; 5 is a diagram of a device for balancing gravity with a gas cylinder, in which a balancing cylinder is integrated; 6 is a device for balancing gravity with a balancing cylinder located inside the gas cylinder, and with an additional distributor of accelerated lowering.

The device for balancing gravity contains working equipment 1, balancing cylinder 2, the main hydraulic cylinders 3, the distributor of the working fluid 4, the hydraulic line 5; a gas cylinder 6 is connected to the piston cavity of the balancing cylinder (figure 3); a hydraulic pump 7 connected to the distributor of the working fluid 4. A second distributor of the working fluid 8 can be connected to the hydraulic line 5 (FIG. 4), allowing to select the operating modes (speed, power); balancing cylinder 2 may be located inside the gas cylinder 6 (figure 3) coaxially to it; the distributor of the working fluid 9 floating mode is connected to the hydraulic line of the main hydraulic cylinder 3.

The essence of the device for balancing the gravity of the working equipment is to bring the gravity of the working equipment to the rod of the balancing cylinder according to the equation

where T is the reduced gravity on the rod of the balancing cylinder;

G _i , h _i - respectively, the gravity of the elements of the working equipment and their shoulders;

h is the shoulder of the balancing cylinder.

The reduced force T on the rod is balanced by the gas pressure on the piston

T = A ₁ p,

where A ₁ is the piston area of the balancing cylinder;

p is the pressure in the gas cylinder.

The best effect of the device is achieved with a constant gas pressure in the cylinder.

To ensure a constant gas pressure in the cylinder, the condition

V _Г ≥ (10 ... 12) V ₂ ,

where V _G is the volume of the gas cylinder;

V ₂ - the working volume of the balancing cylinder.

Thus, due to the balancing of gravity when lifting the working equipment with the load in the bucket in the main hydraulic cylinders, loads arise only from the gravity of the load in the bucket and from the inertia forces during acceleration and braking of the working equipment, as well as from the friction forces in the hinges.

The proposed balancing device really provides balancing of the gravity of the working equipment, eliminates the need to convert the potential energy of the gravity of the working equipment to the potential energy of gas compression in the pneumatic accumulator and eliminates the energy loss due to friction in hydraulic lines.

The device operates as follows. To raise the boom 1, the spool of the distributor of the working fluid 4 is turned into the lower position, the working fluid from the pump 7 is fed into the piston cavities of the main hydraulic cylinders 3, lifting the boom. At the same time, a constant gas pressure acts in the piston cavity of the balancing cylinder 2, balancing the gravity of the working equipment.

Stop lifting the boom by installing the distributor of the working fluid 4 in the neutral position, shown in figure 3.

To lower the boom 1, the spool of the distributor 4 is moved to the upper position, the working fluid from the pump 7 is fed into the rod cavities of the cylinders 3 and 2, while the working fluid is drained from the piston cavities of the cylinders into the tank.

The device in figure 4 provides two speeds for lowering the working equipment. When the spool valve 8 is in the position shown in figure 4, when lowering the boom 1, the working fluid from the pump 7 is fed into the rod cavities of the cylinders 3 and 2, provide the first estimated speed of lowering the boom 1 (greater burial force on the tooth of the bucket). If the valve spool 8 is installed in the upper position, then the working fluid from the pump 7 when lowering the boom is served only in the rod cavity of the hydraulic cylinders 3 and provide a second increased speed of lowering the boom.

The device in FIG. 5 is characterized by a combined execution of a balancing cylinder 2 and a gas cylinder 6 in one housing. The principle of operation of the device differs from the previously considered figures 3, 4 in that the rod cavity of the balancing cylinder 2 is connected to a drain hydraulic line. The presence of the working fluid in the rod cavity of the cylinder 2 is a positive factor providing lubrication of the rubbing parts and sealing of the gas piston cavity of the balancing cylinder 2.

In Fig.6, the device provides three modes of operation: normal mode of operation - lifting, with balancing of gravity; lowering with balancing of gravity and a floating mode of accelerated lowering of the working equipment. Figure 6 shows the position of the valve spool 9, providing a mode of balancing the gravity of the working equipment. The valve spool 9 is turned on to the right position only when lowering the working equipment, when the piston cavities of the cylinders 3 and the rod cavities of the cylinders 2, 3 are connected to each other and to the drain hydraulic line, while the accelerated lowering in the floating operating mode of the working equipment is performed.

The proposed device can be used on jib machines with a cyclic nature of the working process when developing the soil, mining, etc., when the processes of raising and lowering the working equipment are alternated. The device allows you to save fuel and energy spent on lifting the working equipment, to increase the overall efficiency of the machine.

Sources of information

1. Copyright certificate No. 543715, M.cl. ² E 02 F 9/22, BI No. 3, 1977.

2. Patent for invention No. 2190062, class. ⁷ E 02 F 9/22, BI No. 27, 2002.

Claims (2)

1. The device for balancing the gravity of the working equipment of the boom machine, containing working equipment, at least one main, one balancing cylinder and at least one gas cylinder and one distributor of working fluid, characterized in that the piston cavity of the balancing cylinder is connected to the gas cylinder. 2. The device according to p. 1, characterized in that at least one balancing cylinder is located inside the gas cylinder coaxially with it.

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