RU2631060C2 - Thrust drive of mine excavator - Google Patents

Abstract

FIELD: transportation.

SUBSTANCE: method is implemented by means of executing the thrust drive of a rack mine excavator in the form of two drive motors connected by a V-belt drive with the corresponding gearboxes arranged in a double-beam boom, on the output shafts of which rack gears are installed. The rack gears are interfaced with racks located on a handle. In the boom beams, cylindrical cups are symmetrically made. The gearbox housings are cylindrical and are arranged in the cups of the boom beams in the form of removable blocks. The cylindrical seating surface is coaxially located on the outer surface of the gearbox housings, and flanges with openings for bolting to the boom are located at the ends of the gearbox housings. The input shaft of each gearbox is equipped with a brake combined with the pulley of the V-belt drive, and the distance between the rack gears is more than twice the width of the gear. A sprocket connected with an encoder is installed on one of the output shafts of the gearboxes.

EFFECT: creating a reliable thrust drive, increasing its maintainability, namely, carrying out repairs by means of removing the gearbox unit without disassembling the transmission, simplifying the installation of the thrust drive and the possibility of dismantling the rack gears without dismantling the gearboxes.

2 cl, 1 dwg

Description

The invention relates to mining machines used in the development of mineral deposits in an open way, namely to mining shovels of the "direct shovel" type with electromechanical drives of the main mechanisms.

The drive mechanism of the pressure of a single-bucket excavator is necessary for the translational movement of the handle when digging, its introduction into the face and removing soil by moving the bucket by the excavator lifting mechanism.

An analogue of the claimed device is a rope drive of the pressure head of an excavator ECG-10 manufactured by IZ-KARTEKS named after P.G. Korobkova ”(EKG-10 type crawler mining excavators“ Operation manual 3536.00.00.000 RE ”, Izhorskiye Zavody OJSC, St. Petersburg, 2000).

The drive consists of a drive motor mounted on a rotary platform and a gearbox connected to it, on the output shaft of which there are drums with pressure and return ropes enveloping the blocks mounted on the pressure axis and attached to the ends of the handle. By changing the length of the rope when winding it onto the drum, the reciprocating movement of the handle is carried out when digging.

The advantage of this design is to reduce the dynamics of the pressure drive due to the flexibility of the rope and the location of the drive motor and gearbox on the rotary platform of the excavator, which reduces the load on the boom and reduces the moment of inertia of the rotary part of the excavator relative to the central axle, thereby reducing the load on the rotation drive.

The design drawback is the low durability of pressure ropes, the frequent replacement of which leads to a loss in excavator performance. In addition, the location of the two-strand bypass blocks on the pressure axis from two sides of the handle significantly complicates the design and periodically requires additional adjustment. Another drawback of the design is the need for periodic sampling of the weakening of the pressure rope in connection with its extraction during operation.

Another analogue is the rack drive of the pressure head of the EKG-12 excavator manufactured by the Ural Heavy Engineering Plant (Excavator - EKG-12, Operating Instructions, 11075.00 IE, Yekaterinburg, 2001).

The drive consists of a drive motor located on the boom in the area of the pressure shaft, connected by a coupling to a drive gear installed inside the boom housing. On the last (output) shaft of the gearbox, the power flow is split into two flare gears mounted on the consoles of the output shaft, due to the interaction of which with the rails mounted on the handle, the handle moves back and forth during digging.

The disadvantage of the design of such a pressure drive is low maintainability, eliminating the possibility of repair by the aggregate-node method. Since the metal structure of the boom is used as the gearbox housing, repair or replacement of worn parts, if necessary, is carried out to repair or replace parts in the field, which adversely affects the conditions and results of repair, especially at low temperatures. Sending the gearbox to the repair facility together with the boom is not economically feasible, since it requires a large amount of installation work with the presence of load-lifting and heavy-duty vehicles, which in turn entails long-term downtime of the excavator.

In addition, the split power on the output shaft of the gearbox requires not only the location of the contact surfaces of the teeth of the two gear wheels in the same plane, but also a similar arrangement of the teeth of the two cast racks welded to the handle beams. This requirement for rails located at a considerable distance with large allowances for the thickness of the molten tooth is technologically very difficult to carry out.

Failure to comply with this condition leads to the transfer of the entire power flow to one rail through one rack gear, which adversely affects the operation of the pressure head.

A design drawback is also the lack of a flexible connection in the pressure head, as a result of which dynamic overloads and shocks in the pressure head are transmitted in full to the drive motor.

The prototype of the invention is the MARION 301M excavator (Promotional brochure DRESSER MARION, DRESSER INDUSTRIES, INC, MARION DIVISION, 617 West Center Street, P.O. Box 505, Marion, Ohio 43302), in the construction of which the above-mentioned disadvantages of analogues have been partially eliminated.

The drive of the prototype pressure head is made with separation of the power flow and consists of two electric motors mounted on the box-section beams of a double-beam boom, each drive shaft having a drive gear engaged with a gear wheel located on the intermediate shaft. Each intermediate shaft extends from the inside of the beam to the outside and relies on bearings mounted on the beams. A second pinion gear is installed at the opposite end of the countershaft, which engages with a gear wheel mounted on the pressure shaft. The second gear train is enclosed in a separate oil bath.

Each pressure shaft passes inside the box beam from its outer side to the inner one. On the output end of each pressure shaft, on the inside of the box-shaped beams, there is a cremeler gear that engages with the handle rail and a support roller that accepts the weight of the handle and reactions in the saddle bearing that arise when digging.

Pressure shafts are supported by bearings mounted in glasses welded into vertical sheets of boom beams.

Significant disadvantages of the prototype are:

- The drive is assembled directly on the boom from separate units, which complicates its installation and adjustment in the field and excludes the possibility of repair by the aggregate method (complete replacement of the unit).

- Replacing the ratchet gear is a very time-consuming operation, because there is practically no distance between the gears, it is impossible to remove the cremeler gear from the pressure shaft, shifting it inside the boom, in this case the gear will abut against the roller of the opposite pressure shaft. To remove the gear, it is necessary to extend the pressure shaft with bearings out of the boom, having previously disassembled the oil bath of the second gear and the gear itself. Also, with repeated dismantling of the bearings, their seating surfaces in the boom glasses are damaged. Restoring the landing surfaces is an extremely time-consuming operation associated with the dismantling of the boom and its transportation to the repair facility.

- The presence of the supporting rollers of the handle on the pressure shaft determines the pressure on the pressure shaft due to the weight of the handle and reactions in the saddle bearing that occur when digging soil, which leads to the need to increase the working cross sections of the pressure shaft, the load bearing capacity and increase the support elements in the boom. This circumstance leads to an increase in the weight and size parameters of the assembly and its weight.

- Installation of the brake on the motor shaft does not provide braking of the mechanism in case of breakdown of the pressure drive elements.

The technical task of the invention: the creation of a reliable pressure drive, increasing its maintainability, namely, carrying out repairs by removing the gear unit without disassembling the transmission, simplifying the installation of the pressure drive and the possibility of dismantling the ratchet gears without dismantling the gearboxes.

The technical problem is solved by performing the drive pressure of a rack and pinion excavator in the form of two drive motors connected by a V-belt drive with corresponding gearboxes located in a double-beam boom, on the output shafts of which are mounted gear wheels. The gear wheels are coupled to the racks located on the handle.

In the boom beams, cylindrical glasses are symmetrically made. The gearboxes are cylindrical and placed in glasses of boom beams in the form of removable blocks. A cylindrical seating surface is coaxially located on the outer surface of the gear housings, and flanges with holes for bolting to the boom are located on the ends of the gear housings. The input shaft of each gearbox is equipped with a brake combined with a V-belt pulley, and the distance between the rack gears is more than twice the width of the gear.

An asterisk is installed on one of the output shafts of the gearboxes, connected to the handle limiter - an encoder.

The implementation of cylindrical cups for gearboxes in the handle beams allows the gearboxes to be completely placed in the housings, which simplifies their installation - dismantling the pressure drive and eliminates accidental breakdowns and destruction, increasing the reliability of the pressure drive.

The execution of the gear housing is cylindrical and the presence of a cylindrical landing surface allows you to center and fix the gear housing in the boom cups, ensuring alignment of the shafts of the left and right gears, which also increases the reliability of the pressure head drive.

The presence of flanges with holes for bolting on the ends of the gear cases allows you to rigidly fix the gears in the boom beams and eliminate their axial displacement, increasing the reliability of the pressure head drive.

The presence of a brake on the input shaft of each gearbox allows to reduce the flywheel moment, and the combination of the brake with a V-belt pulley allows to reduce the weight and dimensions of the pressure drive.

The arrangement of the gear wheels at a distance greater than twice the width of the gear allows them to be removed when damaged and replaced without dismantling the gearboxes.

Installing an asterisk connected to the encoder on one of the output shafts limits the handle movement within the specified limits, which eliminates the impact of the handle when moving it against the front and rear stops.

The figure shows the drive head of a quarry excavator, which is two symmetrical blocks, including drive motors 2 mounted on box-shaped boom beams 1 and gearboxes 4 mounted in cylindrical cups 3 of boom boom 1 in cylindrical bodies.

On the output (pressure) shafts 5 of the gearboxes 4, rack-mounted gears are mounted 6. The connection of each gearbox 4 with the corresponding drive motor 2 is carried out by a V-ribbed belt 7, envelope the pulley 8, mounted on the output shaft of the drive motor 2, and a pulley 9, mounted on the input shaft of the gearbox 4 The pulley 9 is combined with the pulley of a normally closed brake 10. The gear wheels 6 are engaged with the racks 11 of the handle 12.

Each gearbox 4 has a landing cylindrical surface 13 and a flange 14, in the holes of which bolts 15 are installed. On one of the pressure shafts 5 of the gearboxes 4 an asterisk 16 is mounted, connected by a chain 17 to the asterisk 18 of the encoder for restricting the movement of the handle (hereinafter the encoder) 19.

The fixation of the gearboxes 4 in the cups 3 of the boom 1 in the radial direction is carried out by the seating surfaces 13 of the gearboxes 4, and in the axial direction by bolts 15 installed in the holes of the flanges 14 connected to the bodies 4.

The drive pressure quarry excavator works as follows. When the motors 2 are turned on, the torque from the 2 pulleys 8 installed on the output shaft of the pulley 8 with V-ribbed belts 7 is transmitted to the pulleys 9 of the gearboxes 4. When the motors 2 are turned on, voltage is applied to the coils (not shown) of the brakes 10. The brake 10 is released, thereby providing transmission of torque from the pulley 9 mounted on the input shaft of the gearbox 4 through the gears of the gearboxes 4 (not shown in the figure) to the output (pressure) shafts 5 and the gear wheels 6. The gear wheels 6, inter working with rails 11, provide translational movement of the handle 12. The direction of movement of the handle 12 is determined by the direction of rotation of the drive motors 2 set by the excavator driver. In this case, the automation excludes the inclusion of engines 2 in which the gear wheels 6 would rotate in different directions (emergency mode).

When the pressure shaft 5 rotates, the sprocket 16 mounted on it and the sprocket 18 connected to it 17 rotates the input shaft of the encoder 19. The encoder 19 is configured so that for a certain number of revolutions of its input shaft (not shown), determined by the number of revolutions pressure shaft 5, the corresponding drive motor 2 is turned off and thereby stop the movement of the handle 12. The corresponding setting of the encoder 19 provides the necessary movement for removing chips when digging the handle 12.

The invention was used in career excavators EKG-32R and allowed:

- to simplify installation and obtain a drive of high maintainability pressure due to the possibility of its implementation by the aggregate method (removal of the gear unit) without disassembling the transmission;

- to increase the reliability of the pressure drive by eliminating the effects of the weight of the handle and reactions in the saddle bearing when digging pressure reducers (pressure shafts) onto the output shafts;

- reduce the number of seals in the drive pressure;

- dismantle the gear wheels without dismantling the gearboxes.

Claims (2)

1. The drive pressure of a rack and pinion excavator containing two drive motors connected by a V-belt drive with gearboxes located in the double-beam boom, on the output shafts of which are mounted gear wheels coupled to the racks located on the handle, characterized in that the cylindrical glasses are symmetrically made in the boom beams , gear housing is cylindrical and placed in glasses of boom beams in the form of removable blocks; a cylindrical landing surface is coaxially located on the outer surface of the gear housings, and flanges with holes for bolting to the boom are located on the ends of the gear housings; the input shaft of each gearbox is equipped with a brake combined with a V-belt drive pulley, and the distance between the rack gears is greater than the doubled gear width. 2. The pressure head drive of a mining excavator according to claim 1, characterized in that an asterisk is mounted on one of the output shafts of the gearboxes and connected to the handle limiter by an encoder.

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