Abstract:
The invention relates to a vessel for mixing a cell lysate. The invention also relates to a method of using the vessel to mix a cell lysate in order to obtain high-purity products such as nucleic acids or proteins for use in a variety of applications. The invention also relates to a method for monitoring the degree of cell lysis in a cell suspension by measuring the viscosity of the cell suspension.
Abstract:
A method for the measurement of rheological properties of high density slurry materials and in particular high density mill tailings. A sample of the tailings is placed within a mixing tub, with mixing paddle used to effect the mixing. A digitally controlled electric motor is used to directly drive the paddle at a constant predetermined speed or speeds. Feedback control elements, including a variable speed drive and a computer constantly monitor the mixing speed and compensate for deviations therefrom. The tub is laterally pivotable against a load cell for a direct determination of reaction torque with correlation to viscosity and other rheological properties of the mill tailings. The load cell emits signals which are conditioned and fed to the computer which correlates torque to speed and determines the rheological properties on a continuous real-time basis. The computer also compares determined torque/speed parameters to stored rheological properties of known materials.
Abstract:
A method to oxidize an oxidizable component in a liquid phase with an oxygen-containing gas is disclosed. The method comprises mixing the liquid phase and gas phase in a reactor with a rotating agitator element operated at constant power.
Abstract:
An apparatus for selectively controlling a plurality of electric motors for driving individual work objects, the apparatus including an electrical switch which is adapted to produce predetermined speed signals for the electric motor selected, a programmable controller disposed in signal receiving relation relative to the electrical switch and which is adapted to generate a predetermined signalling sequence in response to the signal received from the electrical switch, a variable speed motor drive electrically coupled with the programmable controller, and with the electric motor selected, the variable speed motor drive selectively driving the selected electric motor at a predetermined speed in response to the signalling sequence received from the programmable controller, and a sensor adapted to indicate the work performed by the electric motor whereby the electric switch may be selectively adjusted to control the operation of the electric motor selected.
Abstract:
An orbital shaker apparatus which has a tray for cyclic motion is flexibly suspended from a frame which is flexibly suspended from a plurality of stationary supports. The flexible suspension constrains the tray to move only translationally along one axis with respect to the frame and constrains the frame to move only translationally along one axis perpendicular to the tray movement axis. A microprocessor is used for receiving operator input to set the speed and duration of the cyclic motion. Embodied in the microprocessor is a closed loop speed control which measures the actual speed of the cyclic movement with an interrupt routine which calculates the duration between the pulses of an optoelectric speed sensor. The actual speed is compared to the set speed and a digital "bang-bang" control signal is generated to regulate motor velocity from the difference between the two speeds.
Abstract:
At least two levels of mixing, one adjacent the top of the vessel and one adjacent the bottom of the vessel are provided and individually driven at appropriate speeds to produce a single flow pattern in the fluid in the vessel. The bottom mixing apparatus is preferably a single large diameter impeller whereas the top mixing apparatus includes a plurality of smaller diameter impellers positioned equally distant from and symmetrical about the lower impeller's vertical axis of rotation. Each of the impellers have a converging flow field exiting the impeller.
Abstract:
An emulsification tester for determining the amount of water a known amount of material such as printers ink or shellac will absorb when agitated or mixed a precise number of times and in a precise manner is disclosed. As is well known by those skilled in the art, certain materials, especially materials such as shellac and printers ink, will not function properly unless these materials have the ability to absorb a proper amount of water. That is, the material must be able to absorb a minimum amount of water but must not absorb an excess amount of water. The tester of this invention allows a precise amount of water and a material to be tested (such as printer ink) to be agitated by mixer blades rotating at a precise selected speed and for a precise number of revolutions. In addition, the tester of this machine further includes means for very positively but slowly rotating the container such that the mixer blades clearly come into contact with all portions of the material in the container and leaves none unagitated. Thus, as an example, the water absorption characteristics of printers ink can be determined after a precise amount of agitation simply by pouring off and measuring the remaining water. The apparatus comprises a heavy-duty mixer which uses a precise DC electric motor which in turn drives a gear box connected to the mixers or agitators such that the agitators rotate at a precise revolution per minute. The container itself is driven at a slow speed (approximately 4 RPM) by a small AC motor. A sensing means connected to one of the agitators or mixer blades senses each revolution of the blades. A pulse representative of each of these revolutions is then provided to a count-down counter which counts each pulse received from said pulsing means. Thus, when a selected number of turns is preset in the counting means, and the machine started, it will be appreciated that once the counter reaches zero, electrical power is interrupted to the DC motor and AC motors thereby stopping the agitation. A light indicator, buzzer or other audible device may be attached to give notice that the mixing is complete. At that time, the water can be poured off and measured to determine the amount absorbed.
Abstract:
Apparatus for controlling delivery of power to a grain stirring apparatus is disclosed. A bridge frame (21) is supported between a shaft (34) and a circular track (24) on the wall (11) of bin (10). Frame (21) supports a trolley mechanism (45) having a rotating auger (47) operatively attached thereto. Frame (21) moves orbitally around bin (10) as trolley (45) moves radially inward and outward thereby allowing auger (47) to stir grain (12).The apparatus for controlling power delivery has a switch (151) which senses orbital movement using roller (191) to follow cam (190) fastened to shaft (34). If orbital movement is not appropriately sensed, timer (117) causes relays (119) and (133) to open thereby powering off grain stirring apparatus (20).
Abstract:
A mixing apparatus for mixing fluids, such as drilling muds, in a reservoir, each fluid having different densities requiring different torques for proper mixing thereof, with the mixing apparatus having provisions therewith operatively controlling the motor mechanism for limiting the maximum horsepower of the motor mechanism absorbed in mixing the fluid to substantially the rated horsepower of the motor mechanism to prevent overloading of the motor mechanism.
Abstract:
A system for conditioning bulk material comprising a mixer having a mixing chamber and motor means driving a rotary mixing element in the chamber; an automatically controlled discharge system for discharging material from the chamber at a selected constant rate, the discharge system comprising an outlet opening formed in the mixing chamber, a discharge door adjacent the opening mounted for reciprocal vertical movement between a closed position covering the opening and an open position uncovering the opening, and a fluid motor for normally maintaining the door in a fixed neutral position partially uncovering the opening and operable to move the door out of the neutral position when a selected variation in load on the motor means is exceeded and to return the door toward said neutral position when the variation is no longer exceeded.