This present invention is directed to a water cutting assembly and nozzle nut that allows a more cohesive high velocity water stream for cutting of materials.
High pressure water assemblies 100 typically include a nozzle 120 and a retainer 102 secured to the nozzle by a nut 108 (
Manufacturers continue to strive to create more cohesive water streams and therefore faster and more accurate and precise cuts. Therefore, with any water cutting assembly, a cohesive and narrow water stream is desired to create a water cutting apparatus that is more efficient, precise and accurate. Most improvements to the water stream cohesiveness relate to the orifice passage.
In view of the above, the present invention is directed to an assembly for a water cutting apparatus that includes an improved nozzle assembly that improves the cohesiveness of the exiting water stream. A more cohesive water stream at high pressure allows for more efficient operation and faster cutting times.
The present invention includes an end assembly for a water cutting apparatus comprising a nozzle, a nut coupled to the nozzle, and a collimating chamber defined between the nozzle and the nut. The collimating chamber has a volume and a portion of the volume is formed by each of the nut and the nozzle.
The nozzle may include a first end and an opposing second end, with an elongated passageway extending between the first and second ends. The elongated passageway includes an expanded area portion. The nut may include an orifice assembly, so that the nut, nozzle and the orifice assembly define a collimating chamber. The orifice assembly includes a retainer having an inner profiled surface extending from the nut to the orifice member with a decreasing diameter. The expanded area portion, in combination with an inner profiled surface cooperate to create an enlarged collimating chamber.
A nut having an orifice member for use with a water cutting apparatus. The nut includes a cavity having a threaded area, a sealing surface, a profiled surface and orifice cavity. The sealing surface is located between said threaded area and said profiled surface. An orifice assembly is retained within the orifice cavity. The orifice assembly includes an orifice and a retainer having an inner retainer profile.
Further scope of applicability of the present invention will become apparent from the following detailed description, claims, and drawings. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art.
The present invention will become more fully understood from the detailed description given here below, the appended claims, and the accompanying drawings in which:
As illustrated in
The nozzle 20 generally includes an elongated body 21 which defines the inlet passage 24. At a first end, not illustrated, the nozzle 20 is connected to an apparatus that provides high pressure water to the inlet passage 24. Many prior art nozzles have a collimating chamber at the first end, and the present invention may also have a variety of configurations at the first end, including a collimating chamber. The apparatus or assembly to which the nozzle 20 is coupled may be a robotic arm capable of movement. At the second end 23, the nozzle 20 includes threads 26 or other coupling means and an inner wall or a first profiled surface 28 that defines an expanded region 29 which forms at least a portion of the collimating chamber 80. The nozzle 20 also includes a seal surface or a first engagement surface 22 which allows the nozzle nut 30 to be coupled to the nozzle 20 with a water tight seal. The first engagement surface 22 meets the first profiled surface 28 at an inner nozzle edge 29. While the first engagement surface 22 is illustrated as being in a plane perpendicular to the axis of the inlet passage 24, other geometric configurations may be used such as a beveled surface, so long as the nozzle nut 30 is capable of being sealed to the nozzle 20 to withstand the high pressures within the inlet passage 24 and collimating chamber 80.
The nozzle nut 30 defines a cavity 31 having a threaded portion 39, a second engagement or seal surface 32, an inner wall or second profiled surface 36, an orifice cavity 38, and an outlet passage 34. The threaded portion 39 allows the nozzle nut 30 to be threaded onto the nozzle 20 although other means of connection may be used. The second engagement surface 32 creates a water tight seal with the first engagement surface when the nozzle nut 30 is coupled to the nozzle 20. The orifice cavity 38 is designed to receive the orifice assembly 70. The second profiled surface 36 is located between the orifice cavity 38 and the second engagement surface 32. While in the first example in
The orifice assembly 70 which fits within the orifice cavity 38 on the nozzle nut 30 includes an orifice member 50 and a retainer 40. The orifice member 50 is typically formed out of a hard material such as sapphire, ruby, or diamond and has an orifice passage 52 which restricts the flow of the high pressure water within the collimating chamber 80 to a very small outlet to create the high velocity water stream. The retainer 40 is formed from titanium, however alternate materials such as delrin, acetal, peek or other materials with similar properties may be used. The retainer 40 includes tabs or fingers 44 which hold the orifice member 50 in place. The tabs or fingers 44 create a spring-like effect to hold the orifice member 50 in place. While being illustrated as planar in
The inventors have found that a high velocity stream exiting through the orifice passage 52 may be improved to have tighter more cohesive stream characteristics and thereby provide improved cutting performance by having the water pass through an inlet passage 24 into a collimating chamber 80 wherein the collimating chamber 80 expands in diameter over the inlet passage 24. It is believed that the expanded diameter allows better flow movement before entering the orifice passage 52, which helps create the improved high velocity stream exiting the orifice passage. The expanded collimating chamber allows an area for the turbulence, which is believed to be primarily caused by the velocity of the water, to subside or calm as the water is being directed to the orifice passage. The reduction in turbulence is believed to result in an improved, more cohesive water stream exiting the orifice passage. Of course, the collimating chamber 80 is formed primary without sharp edges that may cause turbulence. The collimating chamber 80 may take on almost any shape so long as it expands in diameter. More specifically, it has been found that a smooth expansion in diameter from the inlet passage with a smooth reduction in diameter to the orifice member 50 is helpful in improving the stream characteristics of the exiting high velocity water stream. Therefore, the retainer 40 has been formed with a somewhat frusto-conical or in cross-section a beveled shape to help transition the reduction in diameter as the water approaches the orifice passage 52. The nozzle nut 30 may also facilitate this reduction in diameter. The collimating chamber 80 in the illustrated embodiment is defined by both the nozzle 20, the retainer, and typically at least a portion of the nozzle nut 30.
The foregoing discussion discloses and describes an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims.