RU2381362C2 - Gearless hydraulic drive of mining machine - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: invention is related to mining industry and is intended for mining machines, and specifically, for hydraulic drive. Gearless hydraulic drive of mining machine consists of body, power cylinders, crank and cam shafts joined to each other by means of mechanical transmission, unit of distribution valves, which are mechanically joined to cam shaft, besides power cylinders are connected at one side by means of hinged joints to body, and at the other side their stems are movably connected to cranks shaft, where driving sprocket of head and drain manifolds is attached. Distributing unit of power cylinders control consists of gates installed in unit body in areas of working fluid flow turn, moreover, pistons of gates have channels that connect cavity of isolated flow to cavity of gate cylinder, besides gates are spring-loaded and have valve part with pusher, and valve seats are arranged with clearance that provides for self-sealing.

EFFECT: less efforts needed to open gates, simplified design, improved reliability of hydraulic drive operation and increased volume efficiency factor.

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Description

The invention relates to the mining industry and is intended for mining machines.

Hydraulic drives of mining machines are known in which the translational movement of the hydraulic jack rods is converted into a rotational drive sprocket of the mechanism of movement of a mining combine (1) or other machines (2).

The main advantage of these drives is their small dimensions, but they are not without drawbacks, as their hydraulic system is controlled by spools, which do not provide tightness and reliability at high pressures of a non-combustible liquid in underground conditions.

The closest technical solution is the hydromechanical drive of the mining machine (3), which includes a housing, power cylinders, a drive sprocket, while it is equipped with crankshaft and cam shafts connected by a mechanical transmission, a block of control valves that are mechanically connected to the cam shaft, power cylinders are connected on one side by hinges to the housing, and on the other hand, their rods are movably connected to the crankshaft on which the drive sprocket is mounted.

The disadvantage of this actuator is the need for significant efforts (t) to open the valves under high pressure working fluid. Because of this, you have to make an additional hydraulic control system for the spools themselves. All this complicates the design and reduces the reliability of the drive.

The aim of the invention is to increase the reliability of the hydraulic drive and its volumetric efficiency. This is achieved by replacing the valves with special hydraulic locks that are installed in the control unit of the power cylinders at the points of rotation of the working fluid flow, and the valve pistons have channels connecting the cavity of the blocked flow to the valve cylinder, in addition, the valve pistons are spring-loaded, have a valve part with a pusher, and valve seats are installed with a backlash providing self-sealing and tightness of the liquid shutoff.

Distinctive features are not known from other technical solutions and ensure the fulfillment of the task, therefore, are essential.

The invention is illustrated by drawings: figure 1 - shows a General view of the drive and a section along aa; figure 2 - communication diagram of the power cylinders, distribution of hydraulic locks, pressure and drain lines and a diagram of the relative position of the hydraulic cylinders; figure 3 is a General view of the valve.

Gearless hydraulic drive (figure 1) consists of a housing 1 placed on a mining machine. Inside the housing 1, power cylinders 2 and 3 are located, connected on one side to the housing 1 by hinges 4, and on the other hand, their rods are connected via bearings 5 to a crankshaft 6, at the output end of which a drive sprocket 7 is mounted, connected directly to the working body of the mountain cars. The crankshaft 6 by means of a mechanical transmission, consisting of gears 8 and 9, is connected to the cam shaft 10, which by means of levers 11 is connected to the pushers 12 distribution pressure 13 and drain 14 hydraulic locks.

The communication scheme (figure 2) of a gearless hydraulic actuator includes pressure 13 and drain 14 hydraulic locks of the power cylinder control unit, pressure 15 and drain 16 of the highway. In the power cylinders 2 and 3, the working area of the piston cavity 17 is greater than the working area of the rod cavity 18.

The water seal (Fig. 3) consists of a control unit housing 19, inside of which there is a valve 20, which is a piston, the upper part of which is made by a valve 21 with a pusher 12 and a valve seat 22. In the water seal there are channels 23 connecting the cavity of the blocked flow 24 with the piston cavity 25 of the shutter 20, within which the spring 26 is located. The piston and the pusher of the hydraulic lock 20, as well as the valve seat 22 have sealing devices 27.

The mechanism works as follows.

When the working fluid 15 is supplied to the pressure line 15 under pressure, the rods of the power cylinders 2 and 3 begin to reciprocate, which, through the crankshaft 6, is converted into rotational motion and transmitted directly to the actuator of the machine, for example, the traction sprocket of a scraper conveyor or drive, without a gearbox stars caterpillar running hydraulic excavator.

At the moment of passage of the so-called “dead spots” by the crankshaft, the distribution valves of pressure 13 and drain 14 automatically switch, as a result of which the piston cavity 17 of the power cylinders 2 and 3 communicates alternately with pressure 15 or drain 16 highways. The rod cavities 18 of the power cylinders 2 and 3 are constantly connected to the pressure line 15, but the difference in the working areas in the piston cavity 17 and the rod 18 allows the piston to move towards the rod cavity, when both cavities are connected to the pressure line 15.

The control of the hydraulic control unit is carried out by a lever-cam mechanism by pressing the pushers 12 pressure 13 and drain 14 valves 20.

The working fluid in the valves 20 (Fig.3) from the cavity of the blocked flow 24 through the channels 23 enters the piston cavity 25. Due to the difference between the areas of the piston cavity 25 of the valve and the working area of the valve seat 22, taking into account the transverse area of the pusher 12, the pressure of the liquid and the spring of the valve 26 the valve part is pressed against the seat 22. In comparison with a conventional valve in the valve, the fluid pressure acts only on a small part of its working area and due to this, a reduction in control efforts is achieved.

Since the valve seat 22 is made with a play, it is centered by the fluid pressure and closes to the valve part 21 of the shutter 20 at the moment of closing, and thus self-sealing and tight shut-off of the flow occur.

Thanks to such a design of the power cylinder control unit, the shutter opening force is reduced, the design is simplified, and thereby the reliability of the drive and its volumetric efficiency are increased.

Information sources

1. "The mechanism of movement of the mining combine." A.S. No. 1350347, M. Cl. Е21С 29/00, BI No. 41, 1987

2. “Power surround drive”. A.S. No. 832108, M. cl. F03C 1/08, BI No. 19, 1981

3. “Hydromechanical drive of a mining machine”. Patent No. 2109946, registered in the state register of inventions 04/27/1998

Claims (1)

Gearless hydraulic drive of a mining machine, comprising a housing, power cylinders, crankshaft and cam shafts, interconnected by a mechanical transmission, a block of control valves that are mechanically connected to the cam shaft, while the power cylinders are connected on one side by hinges to the housing, and on the other hand their rods are movably connected with the crankshaft on which the drive sprocket is fixed, as well as the pressure and drain lines, characterized in that, in order to increase the reliability of the drive and volumetric efficiency, the distribution control unit for power hydraulic cylinders consists of valves installed in the block body at the points of rotation of the working fluid flow, while the valve pistons have channels connecting the cavity of the blocked flow with the cavity of the valve cylinder, in addition, the valves are spring-loaded and have a valve part with a pusher and valve seats are made with a backlash that provides self-sealing.

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