Arrangement and method for heating hydraulic impact device

Patent metadata

Field	Value
Publication number	US-12480364-B2
Application number	US-202418436243-A
Country	US
Kind code	B2
Filing date	Feb 8, 2024
Priority date	Feb 10, 2023
Publication date	Nov 25, 2025
Grant date	Nov 25, 2025

Abstract

An arrangement and method for heating an impact device of a rock treating machine (Rtm) in low-temperature operating conditions is provided. The arrangement includes a warm-up mode (WM) for feeding pre-heated hydraulic fluid through a feed channel to a hydraulic circuit of the impact device. One or more hydraulic accumulators are provided in the hydraulic circuit. The feed channel is provided with a control element for limiting the feeding of the pre-heated hydraulic fluid during the warm-up mode. The control element limits the feeding of the pre-heated hydraulic fluid in the feed channel so that separating elements of the pressure accumulators do not move.

First claim

What is claimed is:

1 . An arrangement for heating a hydraulic impact device of a rock treating machine in low-temperature operating conditions, the arrangement comprising:
a selectively executable warm-up mode for feeding pre-heated hydraulic fluid through at least one feed channel to a hydraulic circuit of the impact device, wherein the hydraulic circuit of the impact device is connected to at least one pressure accumulator provided with pre-charge pressure, wherein the feed channel is provided with at least one control element for limiting the feeding of the pre-heated hydraulic fluid in response to the selected warm-up mode, and wherein the control element is configured to limit feeding of the pre-heated hydraulic fluid in the feed channel so that a pressure is below a first pre-charge pressure of a first pressure accumulator, which is located first downstream of a flow of the fluid being fed.

2 . The arrangement as claimed in claim 1 , wherein the first pressure accumulator is a high-pressure accumulator arranged for storing pressurized hydraulic fluid for executing movement of a percussion piston of the impact device in an impact direction, wherein the hydraulic circuit includes a second pressure accumulator being a low-pressure accumulator provided with a second pre-charge pressure, which is lower than the first pre-charge pressure, and wherein the control element is configured to control the feeding of the pre-heated hydraulic fluid so that pressure at a first fluid space of the first pressure accumulator is lower than the first pre-charge pressure, and that pressure at a second fluid space of the second pressure accumulator is lower than the second pre-charge pressure.

3 . The arrangement as claimed in claim 1 , wherein the control element is a throttle.

4 . The arrangement as claimed in claim 1 , wherein the control element is a proportional valve having an adjustable opening arranged for throttling the pre-heated hydraulic fluid being fed.

5 . The arrangement as claimed in claim 1 , further comprising at least one control unit arranged for at least initiating and terminating execution of the selected warm-up mode.

6 . The arrangement as claimed in claim 1 , further comprising:
at least one control unit; and at least one temperature sensor arranged for providing temperature data, wherein the selected warm-up mode is controlled in response to the temperature data.

7 . A rock drilling rig comprising:
a movable carrier; at least one drilling boom movably mounted to the carrier; at least one drilling unit mounted to the at least one drilling boom and including a feed beam; a rock drilling machine mounted on the feed beam ( 5 ) and including an impact device; and an arrangement in accordance with claim 1 arranged for heating the impact device in low-temperature operating conditions.

8 . A method of heating an impact device of a rock treating machine in low-temperature operating conditions, the method comprising:
conducting pre-heated hydraulic fluid selectively to a hydraulic circuit of the impact device for providing the rock treating machine with a warm-up mode; executing the warm-up mode before initiating a normal operational mode; conducting the pre-heated hydraulic fluid in a hydraulic circuit of the impact device via at least one pressure accumulator provided with a pre-charge pressure; conducting the pre-heated hydraulic fluid through at least one control element to the hydraulic circuit of the impact device during the warm-up mode; and limiting feeding of the pre-heated hydraulic fluid to the impact device by means of the control element for reducing pressure at a first pressure accumulator below a first pre-charge pressure of the first pressure accumulator, which is a first of the at least one pressure accumulator receiving the pre-heated hydraulic fluid in a downstream direction.

9 . The method as claimed in claim 8 , further comprising limiting properties of the conducted pre-heated hydraulic fluid by means of the control element so that an impact cycle of the impact device is operating with reduced operational frequency during the warm-up mode.

Assignees

• Sandvik Mining & Construction Oy

Inventors

• Viitaniemi Jarno
• Parkkinen Pertti
• Leskinen Martti
• Hamalainen Mikko
• Koivumaki Perttu
• Kela Timo
• Kohola Ville

Classifications

• E21B44/06

  in response to the flow or pressure of the motive fluid of the drive · CPC title

• E21B44/02

  Automatic control of the tool feed ({E21B44/005,} E21B44/10 take precedence) · CPC title

• B25D9/12

  comprising a built-in liquid motor {, i.e. the tool being driven by hydraulic pressure} · CPC title

• E02F9/2292

  Systems with two or more pumps · CPC title

• E02F9/22

  Hydraulic or pneumatic drives {(for dipper or bucket arm position control E02F3/43, for blade position control for graders E02F3/844; for turntables E02F9/121; for fork-lift trucks B66F9/22)} · CPC title