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US 7,290,622 B2Granted
Impact device with a rotable control valve
AssigneeSandvik Mining and Construction Oy
InventorsMarkku Keskiniva, Jorma Maki, Mauri Esko, Erkki Ahola
Life of this patent
Estimating the term…
Abstract
An impact device includes a frame to which a tool is connectible, and a stress element that is supported on the frame and disposed between the frame and the tool. A hydraulic control system leads pressurized hydraulic fluid into and out of a hydraulic fluid space such that the stress element causes a stress pulse in the tool. The hydraulic control system includes a rotatingly installed control valve that has control openings for intermittently leading the hydraulic fluid out from the hydraulic fluid space.
Claims17
An impact device for generating a stress pulse in a tool, the impact device comprising:
- a frame to which the tool is connectible;
- a transmission member disposed between the frame and the tool, the transmission member including:
- a transmission piston defining a first pressure surface;
- and
- a tool-side end being in contact with the tool either directly or indirectly at least part of the time during the generation of the stress pulse;
- a stress element generating a force between the frame and the transmission member such that the force tends to push the transmission member towards the tool;
- a first hydraulic fluid space disposed on a tool-side relative to the transmission member and partially defined by the first pressure surface;
- and
- a hydraulic control system for leading pressurized hydraulic fluid into said first hydraulic fluid space and for enabling sudden flow of the hydraulic fluid out of said first hydraulic fluid space such that said force between the frame and the transmission member causes, either directly or indirectly via the transmission member and when the transmission member is in contact with the tool, a force compressing the tool in its longitudinal direction and, due to the effect thereof, a stress pulse in the tool in its axial direction, the hydraulic control system including:
- a hydraulic fluid channel for feeding pressurized hydraulic fluid into the impact device;
- a discharge channel for leading the hydraulic fluid out of the impact device;
- and
- a rotatingly installed control valve having a first set of control openings for leading the hydraulic fluid intermittently from the first hydraulic fluid space to the discharge channel, and the first set of control openings substantially simultaneously open a connection between the first hydraulic fluid space and the hydraulic fluid discharge channel, wherein the control valve includes:
- a second set of control openings for intermittently leading the hydraulic fluid from the hydraulic fluid channel to the first hydraulic fluid space;
- and
- several parallel control channels which simultaneously open a connection between the hydraulic fluid channel and the first hydraulic fluid space in such a way that the connection from the hydraulic fluid channel to the first hydraulic fluid space and, correspondingly, from the first hydraulic fluid space to the discharge channel open alternatively.
13 more elements
An impact device for generating a stress pulse in a tool, the impact device comprising:
- a frame to which the tool is connectible;
- a transmission member disposed between the frame and the tool, the transmission member including:
- a transmission piston defining a first pressure surface;
- and
- a tool-side end being in contact with the tool either directly or indirectly at least part of the time during the generation of the stress pulse;
- a stress element generating a force between the frame and the transmission member such that the force tends to push the transmission member towards the tool;
- a first hydraulic fluid space disposed on a tool-side relative to the transmission member and partially defined by the first pressure surface;
- and
- a hydraulic control system for leading pressurized hydraulic fluid into said first hydraulic fluid space and for enabling sudden flow of the hydraulic fluid out of said first hydraulic fluid space such that said force between the frame and the transmission member causes, either directly or indirectly via the transmission member and when the transmission member is in contact with the tool, a force compressing the tool in its longitudinal direction and, due to the effect thereof, a stress pulse in the tool in its axial direction, the hydraulic control system including:
- a hydraulic fluid channel for feeding pressurized hydraulic fluid into the impact device;
- a discharge channel for leading the hydraulic fluid out of the impact device;
- and
- a rotatingly installed control valve having a first set of control openings for leading the hydraulic fluid intermittently from the first hydraulic fluid space to the discharge channel, and the first set of control openings substantially simultaneously open a connection between the first hydraulic fluid space and the hydraulic fluid discharge channel;
- wherein the stress element includes a second hydraulic fluid space full of hydraulic fluid and partially defined by the transmission member, and the transmission piston defines a second pressure surface located towards the second hydraulic fluid space.
11 more elements
An impact device for generating a stress pulse in a tool, the impact device comprising:
- a frame to which the tool is connectible;
- a transmission member disposed between the frame and the tool, the transmission member including:
- a transmission piston defining a first pressure surface;
- and
- a tool-side end being in contact with the tool either directly or indirectly at least part of the time during the generation of the stress pulse;
- a stress element generating a force between the frame and the transmission member such that the force tends to push the transmission member towards the tool;
- a first hydraulic fluid space disposed on a tool-side relative to the transmission member and partially defined by the first pressure surface;
- and
- a hydraulic control system for leading pressurized hydraulic fluid into said first hydraulic fluid space and for enabling sudden flow of the hydraulic fluid out of said first hydraulic fluid space such that said force between the frame and the transmission member causes, either directly or indirectly via the transmission member and when the transmission member is in contact with the tool, a force compressing the tool in its longitudinal direction and, due to the effect thereof, a stress pulse in the tool in its axial direction, the hydraulic control system including:
- a hydraulic fluid channel for feeding pressurized hydraulic fluid into the impact device;
- a discharge channel for leading the hydraulic fluid out of the impact device;
- and
- a rotatingly installed control valve having a first set of control openings for leading the hydraulic fluid intermittently from the first hydraulic fluid space to the discharge channel, and the first set of control openings substantially simultaneously open a connection between the first hydraulic fluid space and the hydraulic fluid discharge channel, wherein the control valve is installed to continuously rotate in a single direction.
10 more elements
An impact device for generating a stress pulse in a tool, the impact device comprising:
- a frame to which the tool is connectible;
- a transmission member disposed between the frame and the tool, the transmission member including:
- a transmission piston defining a first pressure surface;
- and
- a tool-side end being in contact with the tool either directly or indirectly at least part of the time during the generation of the stress pulse;
- a stress element generating a force between the frame and the transmission member such that the force tends to push the transmission member towards the tool;
- a first hydraulic fluid space disposed on a tool-side relative to the transmission member and partially defined by the first pressure surface;
- and
- a hydraulic control system for leading pressurized hydraulic fluid into said first hydraulic fluid space and for enabling sudden flow of the hydraulic fluid out of said first hydraulic fluid space such that said force between the frame and the transmission member causes, either directly or indirectly via the transmission member and when the transmission member is in contact with the tool, a force compressing the tool in its longitudinal direction and, due to the effect thereof, a stress pulse in the tool in its axial direction, the hydraulic control system including:
- a hydraulic fluid channel for feeding pressurized hydraulic fluid into the impact device;
- a discharge channel for leading the hydraulic fluid out of the impact device;
- and
- a rotatingly installed control valve having a first set of control openings for leading the hydraulic fluid intermittently from the first hydraulic fluid space to the discharge channel, and the first set of control openings substantially simultaneously open a connection between the first hydraulic fluid space and the hydraulic fluid discharge channel, wherein the control valve is rotated by a hydraulic fluid-driven motor.
10 more elements
An impact device for generating a stress pulse in a tool, the impact device comprising:
- a frame to which the tool is connectible;
- a transmission member disposed between the frame and the tool, the transmission member including:
- a transmission piston defining a first pressure surface;
- and
- a tool-side end being in contact with the tool either directly or indirectly at least part of the time during the generation of the stress pulse;
- a stress element generating a force between the frame and the transmission member such that the force tends to push the transmission member towards the tool;
- a first hydraulic fluid space disposed on a tool-side relative to the transmission member and partially defined by the first pressure surface;
- and
- a hydraulic control system for leading pressurized hydraulic fluid into said first hydraulic fluid space and for enabling sudden flow of the hydraulic fluid out of said first hydraulic fluid space such that said force between the frame and the transmission member causes, either directly or indirectly via the transmission member and when the transmission member is in contact with the tool, a force compressing the tool in its longitudinal direction and, due to the effect thereof, a stress pulse in the tool in its axial direction, the hydraulic control system including:
- a hydraulic fluid channel for feeding pressurized hydraulic fluid into the impact device;
- a discharge channel for leading the hydraulic fluid out of the impact device;
- a rotatingly installed control valve having a first set of control openings for leading the hydraulic fluid intermittently from the first hydraulic fluid space to the discharge channel, and the first set of control openings substantially simultaneously open a connection between the first hydraulic fluid space and the hydraulic fluid discharge channel;
- and
- at least one separate auxiliary valve coupled to be controlled by rotation of the control valve such that when hydraulic fluid is fed into the first hydraulic fluid space, each auxiliary valve closes the connection from the hydraulic fluid space to the discharge channel and, correspondingly, when the hydraulic fluid is allowed to flow away from the first hydraulic fluid space, opens the connection from the hydraulic fluid space to the discharge channel.
11 more elements
An impact device for generating a stress pulse in a tool, the impact device comprising:
- a frame to which the tool is connectible;
- a transmission member disposed between the frame and the tool, the transmission member including:
- a transmission piston defining a first pressure surface;
- and
- a tool-side end being in contact with the tool either directly or indirectly at least part of the time during the generation of the stress pulse;
- a stress element generating a force between the frame and the transmission member such that the force tends to push the transmission member towards the tool;
- a first hydraulic fluid space disposed on a tool-side relative to the transmission member and partially defined by the first pressure surface;
- and
- a hydraulic control system for leading pressurized hydraulic fluid into said first hydraulic fluid space and for enabling sudden flow of the hydraulic fluid out of said first hydraulic fluid space such that said force between the frame and the transmission member causes, either directly or indirectly via the transmission member and when the transmission member is in contact with the tool, a force compressing the tool in its longitudinal direction and, due to the effect thereof, a stress pulse in the tool in its axial direction, the hydraulic control system including:
- a hydraulic fluid channel for feeding pressurized hydraulic fluid into the impact device;
- a discharge channel for leading the hydraulic fluid out of the impact device;
- a rotatingly installed control valve having a first set of control openings for leading the hydraulic fluid intermittently from the first hydraulic fluid space to the discharge channel, and the first set of control openings substantially simultaneously open a connection between the first hydraulic fluid space and the hydraulic fluid discharge channel;
- and
- seals adjustable with hydraulic medium and arranged between the control valve and the frame of the impact device, the seals include channels through which the hydraulic fluid is led at least through the discharge channel.
11 more elements
An impact device for generating a stress pulse in a tool, the impact device comprising:
- a frame to which the tool is connectible;
- a transmission member disposed between the frame and the tool, the transmission member including:
- a transmission piston defining a first pressure surface;
- and
- a tool-side end being in contact with the tool either directly or indirectly at least part of the time during the generation of the stress pulse;
- a stress element generating a force between the frame and the transmission member such that the force tends to push the transmission member towards the tool;
- a first hydraulic fluid space disposed on a tool-side relative to the transmission member and partially defined by the first pressure surface;
- and
- a hydraulic control system for leading pressurized hydraulic fluid into said first hydraulic fluid space and for enabling sudden flow of the hydraulic fluid out of said first hydraulic fluid space such that said force between the frame and the transmission member causes, either directly or indirectly via the transmission member and when the transmission member is in contact with the tool, a force compressing the tool in its longitudinal direction and, due to the effect thereof, a stress pulse in the tool in its axial direction, the hydraulic control system including:
- a hydraulic fluid channel for feeding pressurized hydraulic fluid into the impact device;
- a discharge channel for leading the hydraulic fluid out of the impact device;
- and
- a rotatingly installed control valve having a first set of control openings for leading the hydraulic fluid intermittently from the first hydraulic fluid space to the discharge channel, and the first set of control openings substantially simultaneously open a connection between the first hydraulic fluid space and the hydraulic fluid discharge channel;
- wherein hydraulic fluid is fed from a hydraulic fluid pump through the hydraulic fluid channel to the rotating control valve and, correspondingly, from the control valve through the discharge channel to a hydraulic fluid tank, and wherein each of the hydraulic fluid and discharge channels comprise parallel hydraulic fluid channels and discharge channels, respectively, and that a number of openings in the first set of openings of the rotating control valve and the number of parallel hydraulic fluid and discharge channels, respectively, leading to the control valve are multiplied in accordance with the same integer.
11 more elements
Dependencies are inferred from the claim text.