Agitating – Stationary deflector in flow-through mixing chamber
Reexamination Certificate
2001-04-27
2003-07-01
Drodge, Joseph (Department: 1723)
Agitating
Stationary deflector in flow-through mixing chamber
C366S337000, C366S341000
Reexamination Certificate
active
06585407
ABSTRACT:
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the priority of the Swiss patent application No. 830/00 filed on Apr. 27, 2000, the disclosure of which is incorporated herein by reference in its entirely.
BACKGROUND OF THE INVENTION
The present invention relates to static mixing elements and to single stage static mixing element segments having a tubular mixing channel with mixing vanes arranged in that channel. Furthermore the present invention relates to static mixers with static mixing elements and/or single stage static mixing element segments of the before mentioned type, to a mixing vanes element for arrangement in a tubular mixing channel and to a method for mixing very viscous goods, in particular very viscous polyurethane with a curing accelerating agent.
Generally, static mixing elements resp. static mixers are used in applications where two or more streams of free-flowing goods have to be mixed to one substantially homogeneous stream. In the field of adhesives, there are known disposable static mixers for two component adhesive systems which consist of a plastics tube forming a mixing channel and, arranged in lose manner inside that tube, a one-piece mixing unit made of plastics whose mixing vanes are designed as swirl vanes. In the center, said mixing vanes are interconnected with each other in such way that they form a coherent mixing vanes element. Inside said tube, said mixing vanes element abuts, in the area of the exit of said tube, with its mixing vanes which are arranged in flow direction axial at the last position on an axial shoulder of the tube and thereby is, axially in flow direction, supported.
While this mixer design yields good results when mixing low viscous goods at low to medium flow rates, the results when mixing very viscous materials resp. at high flow rates are not satisfactory.
BRIEF SUMMARY OF THE INVENTION
Hence, it is a general object of the invention to provide static mixing elements, single stage static mixing element segments, static mixers, a mixing vanes element and a method for mixing very viscous goods, in particular very viscous polyurethane with a curing accelerating agent, which do not have the before mentioned disadvantages and can be manufactured or performed at low costs.
A first aspect of the invention concerns a static mixing element for mixing at least two components, comprising
a mixing channel of substantially tubular shape which is undivided in axial direction and is formed by at least two separate radial segments and wherein an inner wall of said mixing channel in radial direction forms an outer boundary of a cross section for receiving said components and
mixing vanes arranged in said mixing channel which radially abut on said inner wall of said mixing channel and which are formed by at least one element which is separate from said mixing channel, wherein said mixing vanes comprise a last mixing vane which is arranged axially in flow direction at a last position of said mixing vanes and at least one second mixing vane which is arranged axially in flow direction before said last mixing vane, and wherein at least one of said at least one second mixing vane is, in an area where it radially abuts on said inner wall of said mixing channel, interconnected with said inner wall for transferring axial forces to said mixing channel.
Thus, mixing channel and mixing vanes are formed by separate elements and one or more mixing vanes which are arranged on a position not being, in flow direction, the last axial vane position are interconnected with said inner wall for transferring forces which act in axial direction from said vanes to the inner wall of said mixing channel. This interconnection, which can be established by positive locking, by frictional connection, by glueing or welding or by a combination thereof, effects a stabilization of the axial position of the mixing vanes in the entry area of the mixing element.
As has been mentioned earlier, the inner wall of the mixing channels forms the outer boundary of the cross section of the mixing channel through which the components flow when they pass through the mixing element for being mixed. It encloses this flow path and is, with a large area, in contact with this stream of components. The inner contour of the mixing channel is tubular and preferably of substantially round, preferably of circular cross section. Substantially round cross section means a cross sections with a shape which prevents the formation of dead corners, like e.g. oval cross sections or cross sections of a polygonal shape that approximate a round, oval or similar cross section.
In case a non-round cross section is chosen, a mixing element can be provided in which, when using a uniform swirl vane distribution, the flow is alternately accelerated and decelerated. This can be of advantage in certain applications. Beside the before mentioned shapes of the cross section of the mixing channel it is also planned to use mixing channels with substantially angular and preferably square cross sections. Especially in case the mixing vanes in the mixing channel are simple turbulence vanes oriented transversely to the flow direction of the mixing element, such a cross section can be advantageous.
A mixing channel which in undivided in axial direction is a mixing channel whose inner wall is formed at a given radial position over its entire axial extension by a one-piece element. This means in other words that this mixing channel might be formed by several radial segments each extending over its entire length, but, however, not by several axial segments.
Preferably, the mixing channel is formed by exactly two radial segments each forming one half of said channel.
A second aspect of the invention concerns a static mixing element for mixing at least two components comprising
a mixing channel of substantially tubular shape and of a, in axial direction, substantially constant cross section which is formed by a one-piece element and wherein an inner wall of said mixing channel in radial direction forms an outer boundary of a cross section for receiving said components and
mixing vanes arranged in said mixing channel which radially abut on said inner wall of said mixing channel and which are formed by at least one element which is separate from said mixing channel, wherein said mixing vanes comprise a last mixing vane which is arranged axially in flow direction at a last position of said mixing vanes and at least one second mixing vane which is arranged axially in flow direction before said last mixing vane, and wherein at least one of said at least one second mixing vane is, in an area where it radially abuts on said inner wall of said mixing channel, interconnected by positive locking and/or frictional connection with said inner wall for transferring axial forces to said mixing channel.
A third aspect of the invention concerns a static mixing element for mixing at least two components comprising
a mixing channel of substantially tubular shape which is formed by a one-piece element and wherein an inner wall of said mixing channel in radial direction forms an outer boundary of a cross section for receiving said components and
mixing vanes arranged in said mixing channel which radially abut on said inner wall of said mixing channel and which are formed by at least one element which is separate from said mixing channel, wherein said mixing vanes comprise a last mixing vane which is arranged axially in flow direction at a last position of said mixing vanes and at least one second mixing vane which is arranged axially in flow direction before said last mixing vane, and wherein at least one of said at least one second mixing vane is, in an area where it radially abuts on said inner wall of said mixing channel, interconnected by positive locking through penetration of protrusions in recesses with said inner wall for transferring axial forces to said mixing channel.
In a preferred embodiment of one of the preceding three aspects, the mixing vane or the mixing vanes which are arranged in flow direction axial at the first
Burns Doane Swecker & Mathis L.L.P.
Drodge Joseph
Sika Schweiz AG
LandOfFree
Static mixing element, single stage static mixing element... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Static mixing element, single stage static mixing element..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Static mixing element, single stage static mixing element... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3067701