General Signal Corporation

Other

Marlin D Schutte

Stephen L Markle

William F Hutchings

Robert A Blakley

David J Engel

Joel S Berg

Richard A Howk

Jeffrey S Gambrill

Ronald N Salzman

Keith T McDermott

John M Palmer

Ronald J Weetman

Jonathan C Everdyke

William J Hutchings

George C McIntosh

Craig B Bahr

A mixer gearbox assembly for driving a mixer shaft capable of receiving either a complete electric drive motor on a first face of the gearbox housing for operatively coupling with a first end of a long cross-shaft in the housing, or alternatively a partial electric drive motor on a second face of the gearbox housing for operatively coupling with an opposite end of the cross-shaft. In an alternative configuration for use with only a partial motor, an assembly containing otherwise identical components is provided with a short cross-shaft replacing the long cross-shaft, which short shaft is supported by a single bearing and is colinearly matable only at the outer end thereof with the drive shaft of a partial electric motor. The rotor and short shaft act as a unitary structure when assembled. The alternative configuration can reduce the cost of manufacture of the gearbox assembly through elimination of a motor bearing, a shaft bearing, and a long cross-shaft, and also this configuration eliminates the usual motor pedestal and its coupling, and through use of all other parts identical with those of the alternative-motor assembly.

Mixer gearbox assembly having a cross-shaft alternatively mounted in one

A system for automatically centering and rigidly retaining a mixer shaft in a mixer drive. A hollow quill in a mixer drive is provided with an axial bore having a first diameter along a central portion thereof and tapering linearly and axially in opposite directions away from the central portion with increasing diameter to define a pair of opposed conical portions of the axial bore on either side of the central bore. A smooth-surface cylindrical mixer shaft inserted into the bore is retained by the tightening of upper and lower tapered cylindrical locks which are slidable along the mixer shaft and have conical outer surfaces which are matable with the upper and lower conical portions of the quill bore. The locks, when urged into wedged relationship between the shaft and the quill bore, automatically center the shaft in the quill in rigid retention. The upper end of the shaft is provided with a thrust plate secured by throughbolts into the quill to press the upper lock into locking relationship. At the lower end of the quill, a bearing retainer ring threaded onto the outer surface of the quill is bored to receive bolts extending through a flange on the lower lock to press the lower lock into locking relationship. The rigidity of the lock increases the first critical frequency of the mixer system and therefore permits operation at high speeds, including rotational frequencies greater than the first critical (natural) frequency of the mixer system.

Double taper lock system for a locking a mixer shaft in a quill

The improved steady bearing contains a trap at the distal end of a mixer shaft in a vessel whereby the steady bearing is isolated from materials being mixed. The steady bearing is preferably a dry-running ceramic ball bearing assembly. A hood on the mixer shaft defines a cavity open downward in communication with the interior of the vessel within which cavity the steady bearing is disposed. The cavity is provided with a process fluid, preferably a gas, at a pressure equal to or greater than the hydrostatic pressure of the materials being mixed outside the hood, whereby the materials are excluded from the hood and therefore are prevented from coming into contact with the steady bearing.

Mixer apparatus having an improved steady bearing

A steady bearing on a mixer shaft in a vessel supported from the walls of the vessel by a plurality of pairs of parallel struts which are pivotably mounted at their ends in fixed parallel clevises, the inner clevises being included in a bearing support subassembly and the outer clevises being attached to the vessel wall. The struts and clevises define a plurality of supportive parallelogram structures. The steady bearing is free to slide axially along the mixer shaft. As the vessel expands or contracts in response to changes in internal pressure or temperature as required by process conditions, the shape of the parallelogram structures is free to change to lengthen or shorten the parallelogram diagonals, and in response the steady bearing moves to a new position along the shaft. Radial support of the bearing is maintained at all axial positions assumed by the bearing. The inner clevises are mounted on a clevis carrier which is attached to the bearing holder only through rings at the top and bottom of the holder. The struts and clevises are provided with cooperating faces which can interfere in the event of mechanical failure of the pivot pins to arrest a loose strut and prevent it from catastrophically engaging the mixer impeller. In a similar fashion, this interference prevents the steady bearing assembly from dropping down the shaft, which due to the strut geometry, would cause the shaft to be pulled to the side causing failure of the shaft and/or its supporting components.

Self-adjusting steady bearing support assembly and suspension

A mixer assembly including a driven hollow quill having first and second conical portions in an axial bore and being adapted to receive and mate with a mixer shaft assembly including a mixer shaft having a conical chamfer to mate with the first conical portion and a quill shaft disposed on and removable from the end of the mixer shaft. The quill shaft has a threaded aperture which cooperates with a jack screw rotatably mounted within the quill bore to draw the conical chamfer into preloaded centered relationship with the first conical portion of the quill bore. A tapered sleeve lodged between the mixer shaft and the second conical portion of the quill bore distributes radial loads on the shaft over a large area of the quill, thereby preventing damage to the shaft and quill. A seal assembly on the mixer shaft isolates the housing from the interior of the vessel. The seal is readily removed for replacement. First, the tapered sleeve is released from the second conical portion. Then the jack screw is rotated to drive the mixer shaft assembly axially from the quill bore. When the mixer shaft is free of the seal assembly, the shaft is secured to the vessel wall. The quill shaft is disconnected from the mixer shaft, and the jack screw is counter-rotated to withdraw the quill shaft from the seal assembly, permitting the seal assembly to be removed in a radial direction from the mixer assembly.

Mixer drive apparatus enabling radial changing of shaft seal

A mixer system for aggressive (toxic, hazardous, corrosive, etc.) materials which are mixed (agitated, suspended, circulated, etc.) in a vessel with an impeller connected to a drive shaft has the impeller and its shaft mounted in an assembly which extends through an opening into the tank and closes that opening. The assembly has a cylindrical hub with a passageway through which the shaft extends out of an open end of the hub. Bearings which are made of materials resistant to the aggressive material in the tank are mounted in the hub and journal and support the shaft. The passageway is part of a confinement region which is terminated by a confinement shell which separates inner and outer rotors of a magnet coupling. The inner rotor is connected to the shaft, directly or through a gear train (preferably a planetary gear set). The outer rotor is connected to a drive shaft.

Mixer systems

A mixer system for aggressive (toxic, hazardous, corrosive, etc.) materials which are mixed (agitated, suspended, circulated, etc.) in a tank with an impeller connected to a drive shaft has the impeller and its shaft mounted in an assembly which extends through an opening into the tank and closes that opening. The assembly has a cylindrical hub with a passageway through which the shaft extends out of an open end of the hub. Bearings which are made of materials which are resistant to the aggressive material in the tank are mounted in the hub and journal and support the shaft. There are no dynamic seals which close the confinement region so that the aggressive materials can be present therein. In the event that it is desirable that the bearings be replaceable or the confinement region be sterilized, or purged, an expandable elastomeric collar may be disposed either at the end of the hub below the bearings, which may then be mounted in a cartridge in a hub which is removable therefrom, or in a plate spaced from the hub. Purge or pressure release passages may be provided which are opened and through which purging or sterilizing gas is introduced into the confinement region.

Chuck mechanisms quickly connect and enable quick disconnection of an impeller shaft of a mixer from the drive shaft of the motor unit. A spindle has a keyway which enables a key, either a detent key which is movable in the keyway or a key which is provided by pins extending from the shaft, to be aligned in locking position where the key transfers the thrust from the spindle to the shaft or an unlocked position where the shaft is rotated out of the locking position and may be removed from the spindle. The key is retained in locking position by an outer sleeve or collar having a slot which enables the key to move away from the shaft when the shaft is rotated to the unlocked position. When the collar is rotated to move the slot away from the key, the key is locked against outward movement. The keyway may be sufficiently large to enable the flat on the shaft to tilt the key so as to provide wedging action of the key against the spindle sleeve and tighten the shaft on the sleeve so as to preclude slipping when greater torque is needed by the mixing impeller. In another embodiment, a tapered bolt is used in a cross-bore through the spindle sleeve, which bolt and a flat with a cylindrical undercut define a keyway. A tapered shoulder portion of a bolt which extends into the keyway defines a guide which permits the shaft to be inserted only with the flat in alignment with the cross-bore and keys the sleeve to the shaft when the bolt is screwed into the cross-bore.

Chuck mechanism for detachably connecting impeller shaft and drive unit

The gas outlet of a pipe or other sparging device is encompassed by a cover or cap which is located between the gas outlet and the mixing impeller at the bottom of a vessel. The cap is closed at the top and has a side wall so that the gas bubbles disperse around the lower rim of the wall. The wall may be non-symmetric, such as square in cross section, so as to be at different radial positions with respect to the gas outlet. The gas bubbles, even if released in pulses are distributed spatially and in time. The lower rim is preferable serrated (as a saw tooth edge) with the teeth being of different height, thereby further spreading the distribution of the bubbles as they are dispersed. The overlap or distance between the rim and the gas outlet is such that a sufficient quantity of gas is confined around the outlet to damp pressure pulsations when the pressure of the gas at the outlet does not significantly exceed the hydrostatic pressure at the outlet into the liquid. It is believed that the cap defines an acoustic filter which damps and effectively reduces pressure pulses. A turning cone below the top of the cover and facing the outlet may be used to facilitate more uniform distribution of the gas bubbles.

Mixing system for dispersing a compressible fluid such as gas into

A method for making an end connection for a shaft made of composite material, which accommodates for differences in stiffness, thermal expansion, and chemical resistance between the shaft and the member connected thereto and operates under oscillating torque, thrust, and bending loads, and also provides for manufacturing flexibility in enabling the shaft and connection to be produced as separate parts which are formed when final assembly is to occur. The connection has a male insert which is inserted into the end of the composite shaft. Axial and circumferential grooves are cut in the surfaces of the male insert and the shaft. These grooves are aligned to form circumferential and axial keyways which intersect each other. Material is injected into the keyway and polymerizes to form structural keys which transmit the thrust and torque, while locking the insert member and the shaft permanently together. The bending loads are transmitted through the tight fit extending axially between the composite shaft, insert member and keys. The radial thickness of the end of the shaft, the amount and orientation of the reinforcing fibers therein and the insert are matched so that their stiffness index approximately match. The composite shaft may be connected to a mixing impeller to provide a reliable support and drive therefor.

Method for making an end connection for composite shafts

An end connection for a shaft made of composite material, which accommodates for differences in stiffness, thermal expansion, chemical resistance between the shaft and the member connected thereto and operates under oscillating torque, thrust, and bending loads, and also provides for manufacturing flexibility in enabling the shaft and connection to be produced as separate parts which are formed when final assembly is to occur. The connection has a male insert which is inserted into the end of the composite shaft. Axial and circumferential grooves in the surfaces of the male insert and the shaft. These grooves are aligned to form circumferential and axial keyways which intersect each other. Material is injected into the keyway and polymerizes to form structural keys which transmit the thrust and torque, while locking the insert member and the shaft permanently together. The bending loads are transmitted through the tight fit extending axially between the shaft, insert member and keys. The radial thickness of the end of the shaft, the amount and orientation of the reinforcing fibers therein and the insert are matched so that their stiffness index approximately match. The composite shaft may be connected to a mixing impeller to provide a reliable support and drive therefor.

End connection for composite shafts

Apparatus for mixing particulate material carried in separable containers or process modules rotated with the longitudinal axis thereof at an angle other than 90.degree. to the axis of rotation thereof so that the container rotates asymmetrically with respect to the longitudinal axis thereof. The containers have mixing or process bars rotatably mounted therein and extending also at an angle other than 90.degree. so as to be horizontal when the container is in position for asymmetrical rotation during mixing operations. A docking station of the apparatus has a column connected to the drive shaft at the angle other than 90.degree., an upper arm and a lower arm which is connected to the column and to actuators which tilt the lower arm from a horizontal, container receiving position to a position essentially parallel to the upper arm for clamping the container therebetween. A coupling, between the mixing bar and a shaft which rotates the bar, has a detent which provides for automatic engagement and alignment without manual intervention.

Solids mixing apparatus

Improved draft tube mixing apparatus having one or more of the following features: (a) controlled circulation at the inlet of the tube which allows operation at reduced submergence by preventing formation of a vortex; (b) an additional passage for controlled flow into the draft tube along its length to allow operation without the tube being entirely submerged; (c) the recovery of dynamic energy from the flow at the outlet of the tube by wide area diffusion without separation from the walls of the tube in the diffusing region thereof; (d) improved guidance of radially directed to axially directed flow at the inlet of the draft tube for efficient axial pumping by the impeller by maintaining generally uniform axial flow velocity radially of the impeller; and (e) separation of coarse and fine particles in suspension in the tank to allow selective draw-off of the coarse and/or fine particles thereby increasing efficiency of mixing.

Growing community of inventors

Rochester, NY, United States of America

Marlin D Schutte