Motor vehicles – Special driving device – Portable track
Patent
1995-12-27
1998-09-15
Johnson, Brian L.
Motor vehicles
Special driving device
Portable track
280 611, 280755, B62D 55116
Patent
active
058066160
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The invention relates to an arrangement in a rock drilling equipment for controlling oscillation, comprising oscillation cylinders acting between a body and two crawlers, respectively, an oscillation selector valve allowing the oscillation cylinders to be interconnected during the drive of the equipment so that when one cylinder is extended the other cylinder is contracted, and vice versa.
BACKGROUND
In a crawler-base rock drilling equipment, each crawler is connected to the equipment body by an oscillation cylinder positioned between the crawler frame and the body and a transverse turning axle allowing the crawler to turn with respect to the equipment in accordance with the irregularities of the underlying surface. In order that the equipment would move more evenly in the terrain and would load the body to a lesser extent, the oscillation cylinders are interconnected during normal drive in such a way that when the other crawler turns in one direction with respect to the equipment, the other crawler has to turn correspondingly in the opposite direction, and so the equipment will stay in balance. A drawback of the prior art is, however, that the cylinders have to be interconnected by hoses in order that the equipment could operate, the cylinders could move and the crawlers turn. When a hose is damaged for one reason or another, the pressure escapes from the oscillation cylinders and there is the danger that the equipment may fall over.
SUMMARY OF THE INVENTION
The object of the present invention is to provide an arrangement by means of which the balance of the equipment can be controlled easily and reliably in as many situations as possible. The arrangement according to the invention is characterized in that it comprises locking valves mounted in the oscillation cylinders, said valves being connected to hydraulic lines for the oscillation cylinders such that the flow of pressure fluid out of the oscillation cylinders through the hydraulic lines is normally blocked, and that the locking valves comprise guide means, which release the flow of pressure fluid in the hydraulic lines of the cylinders by a pressure applied to the locking valves. An essential feature of the invention is that the locking valves are mounted in the oscillation cylinders, and connected to the hydraulic lines of the oscillation cylinders such that the hydraulic lines are normally closed, whereby the oscillation cylinders are fixed in the position in which they are. Another essential feature of the invention is that the locking valves are controllable by an external separate pressure, so that they can be e.g. opened automatically while driving the equipment onwards by taking the control pressure from a line which is pressurized during drive. Still another essential feature of the invention is that, if required, the oscillation may be locked out e.g. when the drilling boom or the upper carriage of the equipment turns outwards from the longitudinal direction of the equipment through a predetermined angle. In this way, the risk of falling caused by changes in balance can be avoided.
An advantage of the arrangement according to the invention is that when the hoses between the oscillation cylinders are damaged, the control pressure of the valve may be guided directly into the tank, for instance, and the valves are closed, fixing the cylinders in position so that the crawlers will be locked stationary with respect to the body of the equipment. Further, the equipment is constantly safe as the oscillation is opened only during drive and it need not always be paid attention to separately. Moreover, the invention provides extra safety in that the oscillation can be easily locked out in unusual conditions, and the locking out can be automated by utilizing sensors connected to the turning mechanism of the boom or the upper carriage.
The invention will be described more fully with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic side view of a rock drilling equipment in a partial sec
REFERENCES:
patent: 3012624 (1961-12-01), Lich
patent: 3972557 (1976-08-01), Hudston et al.
patent: 3990583 (1976-11-01), Nishida et al.
patent: 4046209 (1977-09-01), LaCasse
patent: 4341149 (1982-07-01), Dezelan
patent: 4606551 (1986-08-01), Toti et al.
patent: 4614148 (1986-09-01), Bates
Enlund Pentti
Kuisma Jouko
Peltola Seppo
Piipponen Juha
Johnson Brian L.
Lerner Avraham
Tamrock Oy
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