When a surface layer of a paved area is exposed to different temperatures, ageing and vehicles driving over the surface, it may become worn and uneven. For example, heavy vehicles which starts and stops in front of a traffic light, causes the surface layer to shear relatively lower layers. The surface layer can be milled off, and a material of the surface layer may in some cases be recycled and used as aggregate when a new surface layer is paved to replace the old one.
The process of removing the surface layer can be referred to as asphalt milling, profiling, cold planning or pavement milling. During such a process a milling machine or cold planner provided with a large rotating drum or planner equipped with cutting tools can be used. The drum or planner, when rotating, grinds and removes the surface layer of e.g. a road or a parking lot. The cutting/milling is also commonly performed on various kinds of concrete surfaces, such as at bus stops, bridges and runways.
Such a drum can comprise a plurality of tool holders or attachment portions for cutting tools. An example of such a cutting tool is disclosed in US20140232172A1. In US20140232172A1, the cutting tool comprises a body, a shank which can be attached to a drum, and a cutting element.
Cutting tools are also used in several other applications, such as during coal mining or mechanical processing of rocks etc. Cutting tools may also be used during rotary drilling, such as described in WO2010099512A1. Cutting tools may also be referred to as milling tools or milling bits.
A body of the type disclosed in US20140232172A1 can be made of metal and the cutting element can be made of a hard material. When a drum with a number of cutting tools attached to a periphery of the drum is rotated on a paved surface each cutting element on each cutting tool shears away material and hereby the surface layer of the paved surface is removed.
U.S. Pat. No. 6,199,956B1 discloses a shank bit for coal cutting etc. A bit head comprises a tip bit with recesses. The recesses may facilitate introduction of circumferential forces to the bit head. The cutting tool disclosed in U.S. Pat. No. 6,199,956B1 may be suitable in some applications but there remains a need for a cutting tool which can be used for a longer amount of time before it is worn out. There also remains a need for a cutting tool which decreases forces between a surface to be milled and a tool holder and also distributes the forces between the surface to be milled and the tool holder in an advantageous manner. Further, in some milling machines and cold planners cooling of the cutting tool is achieved through water sprayed on the cutting tool. However, it may be difficult to sufficiently cool the cutting tool or some parts thereof. Insufficient cooling may lead to excessive temperature and high wear of the cutting tool. Thus, a problem in this regard is both enabling of sufficient cooling of the cutting tool and that the wear properties and required cutting forces of prior art cutting tools are not sufficiently good.
USPTO Backgrounds
USPTO Backgrounds