Patent ID: 12234727

For the sake of clarity, the figures show some embodiments of the disclosed solution in a simplified manner. In the figures, like reference numerals identify like elements.

Detailed Description of Some Embodiments

FIG.1shows a rock drilling rig1intended for surface drilling. However, the solution disclosed in this document can be implemented in any kind of rock drilling rigs. The rock drilling rig1comprises a movable carrier2and at least one drilling boom3connected to the carrier2. At a distal end portion of the drilling boom3is a drilling unit4provided with a feed beam5and a rock drilling machine6supported on it. A drilling tool7is connectable to the drilling machine6. The rock drilling machine6is hydraulic and comprises a hydraulic percussion device8and a hydraulic rotating device9. The rock drilling machine6may be moved A on the feed beam5by means of a hydraulic feed device10. The carrier2may comprise crawler tracks11which can be driven by means of hydraulic tramming actuators12. The rock drilling rig1is electrically operable and is provided with an operating system, which is accordance with the features disclosed in this document.

FIG.2discloses another rock drilling rig1which differs from the one shown inFIG.1by comprising four wheels13a-13deach of which is provided with hydraulic tramming actuators12a-12d. The tramming actuators12-12dmay be hub motors and selected driving direction as well as steering of the carrier2is based on control of these motors. Arrows B and C demonstrate forces directed to the carrier2when the wheels13on opposite sides of the carrier2are rotated in opposite rotation directions. The tramming actuators12aand12bon the left tramming TL side can be driven by means of one common hydraulic pump and on the right tramming TR side tramming actuators12cand12dmay be driven by means of another common hydraulic pump. More detailed description of the control is disclosed in connection ofFIGS.6and7later in this document.

FIG.2further discloses that the rock drilling rig1comprises an operating system OS provided with an electric system ES and a hydraulic system HS. The electric system ES comprises required apparatuses for providing the system with needed electric energy as well electric motors for generating needed rotation movement for driving hydraulic pumps of the hydraulic system HS. The electric system ES further comprises electric control means for controlling operation of the electric motors, such as rotation speed, rotation direction and torque. The hydraulic system HS comprises, in addition to the mentioned hydraulic pumps, hydraulic tramming actuators12a-12dand hydraulic drilling actuators of the drilling unit4, such as a hydraulic percussion device, a hydraulic rotation device and a hydraulic feed device.

FIG.3discloses that an electric supply source SS of an electrically operable rock drilling rig may comprise an electric energy storage15mounted on-board a carrier or, alternatively or in addition to, there may be a motor-generator unit16for generating the needed electric energy. The motor-generator unit may be a genset provided with a diesel engine and an electric generator. A further possibility is to provide the rock drilling rig with electric cables or corresponding means17for connecting it to an external electric network, such as to an electric network of a mine.FIG.3further shows that the electric supply source SS may a hybrid system comprising two or three of the mentioned energy sources.

FIG.4discloses an operating system OS and its electric system ES and hydraulic system HS. The electric system ES comprises one or more electric motors EM controlled by means of electric control devices18and powered by an electric supply source SS. The hydraulic system HS comprises one or more hydraulic pumps HP and one or more hydraulic actuators HA. The hydraulic pump HP is driven by the electric motor EM and the produced pressurized hydraulic fluid is conveyed to the hydraulic actuators HA through pressure channels. The hydraulic actuators HA comprise tramming actuators12and drilling actuators19, such as a percussion device8, a rotating device9and a feed device10. There are also one or more hydraulic control devices20such as valves for making selections between the hydraulic actuators HA.

The operating system OP comprises also at least one control unit CU for generating control signals and controlling the electrical control device18and the hydraulic control devices20in response to input control parameters and control commands.

FIG.4further discloses that the electric system ES may comprise one or more electric auxiliary devices21such as a compressor22and dust collector23. The control unit CU may also control the electric auxiliary devices21.

The operating system OS may comprise a regenerative braking feature RB and related apparatuses, for controlling the hydraulic pump HP and the electric motor EM so that energy recovery is possible in situations when deceleration of the carrier occurs.

FIG.5discloses that a common electric motor EM and a common hydraulic pump HP are used for selectively driving a tramming actuator12via a closed loop hydraulic circuit24and a drilling actuator19via an open loop hydraulic circuit25. The electric motor EM may be speed controlled and the hydraulic pump HP may be a fixed displacement type pump.

FIG.6discloses a hydraulic diagram of the disclosed solution in a drilling mode andFIG.7discloses the same hydraulic diagram in a tramming mode.

As it is shown inFIG.7the operating system OS and its hydraulic circuit may comprise a first tramming circuit TL for operating first hydraulic tramming actuators12a,12b, and a second tramming circuit TR for operating hydraulic second tramming actuators12c,12d. Both tramming circuits TL, TR have two modes so that they are controllable from tramming modes to drilling modes shown inFIG.6. InFIG.7the tramming modes and their first closed loop hydraulic circuits24a,24bare emphasized, and inFIG.6the drilling modes and their first open loop hydraulic circuit25and second closed loop hydraulic circuit26are emphasized.FIG.7discloses the tramming modes wherein the tramming circuits TL, TR are configured to operate the tramming actuators12a-12dby means of closed loop hydraulic circuits.FIG.6discloses that the first tramming circuit TL is configured to operate a first drilling actuator19aby means of the first open loop hydraulic circuit25and the second tramming circuit TR is configured to operate a second drilling actuator19bby means of a second closed loop hydraulic circuit26. The mentioned first drilling actuator19amay be a feed device10and the second drilling actuator19bmay be a rotation device9. However, it is possible to select the drilling actuators in a different way too.

InFIG.6hydraulic control devices20a-20dare moved to their control position b and inFIG.7they are in their control position a. As can be noted, control positions of selection valves serving as the hydraulic control devices20a-20dcan select whether the hydraulic circuit is connected to the tramming mode or the drilling mode.

Electric control devices18a,18b, such as inverters, can control speed of electric motors EM′, EM″ driving hydraulic pumps HP′, HP″.

FIGS.6and7further disclose that the operating system OS comprises a dedicated open loop hydraulic circuit27for operating a third drilling actuator19c. The open loop hydraulic circuit27comprises a dedicated pumping unit provided with a hydraulic pump HP′″, electric motor EM′″ and an electric control device18cfor controlling their rotation speed. InFIG.6a hydraulic control device20e, which is a selection valve, is in its control position b and directs pressure fluid flow to the third drilling actuator19c, which may be a percussion device8. InFIG.7the valve20eis in its control position a and directs the pressure fluid flow to a hydraulic common rail circuit28to be used by needed auxiliary devices, for example.

The closed loop hydraulic circuits24a,24bmay be provided with a by-pass flow channels29-31allowing limited flow of pressure fluid to be fed from the common rail circuit28through channels29,30to the closed loop hydraulic circuits24a,24b, and further, out of them through channels31to a tank T so that the pressure fluid can be circulated from the closed circuits24a,24b.

The tank T may be slightly pressurized by pressurized air. This may be arranged to prevent cavitation in an inlet port of the first hydraulic pump HP′ when working in the open loop drilling mode,FIG.6. The hydraulic control device20bbetween the pump HP′ and the tank T may cause pressure drop, which can be compensated by the pressurizing the tank T.

The hydraulic circuits ofFIGS.6and7comprise four tramming actuators12a-12dsince the solution pre-sented therein is designed for a four wheeled carrier provided with skid steering. However, the disclosed hydraulic circuits can be slightly modified for controlling two tramming actuators of a carrier provided with crawler tracks.

In case a carrier can be moved and steered with only one tramming actuator, then the tramming actuators12b-12dcan be left out and the electric motor EM′, hydraulic pump HP′ and electric control device18bcan be arranged to control operation of the second drilling actuator19beither via a closed or open hydraulic circuit.

The drawings and the related description are only intended to illustrate the idea of the invention. In its details, the invention may vary within the scope of the claims.