Agitating – Stirrer within stationary mixing chamber – Rotatable stirrer
Reexamination Certificate
1999-06-18
2001-08-07
Walker, W. L. (Department: 1723)
Agitating
Stirrer within stationary mixing chamber
Rotatable stirrer
C366S078000, C366S331000, C277S908000
Reexamination Certificate
active
06270247
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention refers to a mixing and kneading apparatus, comprising a housing delimiting a work space, a working member located in the interior of the housing, a drive assembly for driving the working member to a rotating and to a reciprocating movement, and a sealing assembly located between the housing and the working member. Further, the invention also refers to a sealing assembly for sealing a working member located in a housing and driven to a rotating and reciprocating movement, whereby the sealing assembly is located between the housing and the working member.
Mixing and kneading apparatuses of the kind referred to herein are used, for example, for processing highly viscous masses, for homogenizing and plastifying plastic materials and for admixing fillers and reinforcing additives to such masses.
In order to provide for mixing and processing these materials as homogeneously as possible, such mixing and kneading apparatuses comprise a working member, e.g. a shaft member provided with mixing and kneading vanes, that is driven not only to a rotating movement, but simultaneously to a reciprocating movement as well. One difficulty in using a rotating and simultaneously reciprocating working member consists in the fact that it is very difficult to seal that working member vis-a-vis the housing in such a way that a perfect seal is maintained over an extended period of time. Moreover, caused by the two motions of the working member superimposed to each other, a wobbling motion of the working member can result what renders a reliable sealing even more difficult to achieve.
PRIOR ART
For the purpose of sealing such rotating and simultaneously reciprocating working members, usually elastically resilient sealing members have been used in the past that can absorb both radial deflections and relative axial shifts of the mixing and kneading shaft. However, experience has shown that the life cycle of such sealing members is very limited.
OBJECTS OF THE INVENTION
Therefore, it is an object of the present invention to provide a mixing and kneading apparatus having a sealing assembly that allows for a reliable sealing of the rotating and reciprocating working member over an extended period of time. It is a further object of the invention to provide a sealing assembly for sealing a working member located in a housing and driven to a rotating and reciprocating movement that can fulfill its function reliably over an extended period of time.
SUMMARY OF THE INVENTION
In order to meet these and other objects, the present invention provides, according to a first aspect, a mixing and kneading apparatus, comprising a housing delimiting a work space, a working member located in the interior of the housing, a drive assembly for driving the working member to a rotating and to a reciprocating movement, and a sealing assembly located between the housing and the working member.
The sealing assembly comprises a supporting assembly is located between the housing and the working member. The sealing assembly includes first sealing means and second sealing means. The supporting assembly is rotationally fixed, but coupled to the working member to perform therewith the reciprocating movement.
The first sealing means provide for a rotative sealing of the working member and is located between the working member and the supporting assembly, while the second sealing means provides for a translative sealing of the working member and is located between the supporting assembly and the housing.
According to a second aspect, the invention also provides a sealing assembly for sealing a working member located in a housing and driven to a rotating and reciprocating movement. The sealing assembly is located between the housing and the working member.
The sealing assembly comprises a supporting assembly located between the housing and the working member. It is provided with first sealing means and second sealing means. The supporting assembly is rotationally fixed, but coupled to the working member to perform therewith the reciprocating movement.
The first sealing means is adapted to provide for a rotative sealing of the working member and is located between the working member and the supporting assembly, and the second sealing means is adapted to provide for a translative sealing of the working member and is located between the supporting assembly and the housing.
By the provision of a sealing assembly comprising a supporting assembly located between the housing and the working member and adapted to receive first and second sealing means, the supporting assembly being locked against rotation but coupled to the working member to perform its reciprocating movement therewith, the sealing task can be split into two partial tasks: (1) The first sealing means serving for a rotative sealing of the working member can be located between the working member and the supporting member. (2) The second sealing means serving for a translative sealing of the working member can be located between the supporting member and the housing. By this split into two partial tasks, each sealing means can fulfill its objective in an optimal and reliable manner.
According to a preferred embodiment, the second sealing means can comprise a diaphragm. By providing a diaphragm between the housing and the supporting assembly, the materials to be processed can be prevented from proceeding behind the supporting assembly and clogging it.
REFERENCES:
patent: 4408769 (1983-10-01), Wolff
patent: 4443015 (1984-04-01), Duffee et al.
patent: 4878677 (1989-11-01), Larkins et al.
patent: 5048847 (1991-09-01), Kovacs et al.
Buss Compounding Systems AG
Sorkin David
Tarolli, Sundheim, Covell Tummino & Szabo L.L.P.
Walker W. L.
LandOfFree
Mixing and kneading apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Mixing and kneading apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mixing and kneading apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2538071