Abstract:
Disclosed is an automatic sample changer for sequentially operating on a plurality of samples housed in test tubes, circulated around a continuous track, and sequentially associated with a radiation counting device by way of an elevator mechanism. The continuous track is in modular form, and is designed, respectively, to accommodate fifty, one hundred, two hundred or three hundred samples. Rotating index wheels are employed to drive the samples around the track, with several index wheels being used for the longer tracks. The motors controlling the respective index wheels are reversible, and when more than one motor is employed, the motors may be operated in parallel.Also disclosed is a mechanism for loosely coupling the index wheels to their associated motors to facilitate repair and ensure accurate alignment with the plane of the continuous track. The inventive sample changer is also equipped with an electronic index display which may operate independently of the sample changer power supply, and a mechanism for indicting a low paper level in the print-out roll.
Abstract:
A data analyzing system for scintillation spectrometers of the type for measuring activity levels of samples containing radioactive isotopes and subjected to varying degrees of quench, including methods and apparatus for optimizing counting conditions and thereby improving statistical counting validity irrespective of the degree of quenching present in any given sample, and wherein a measured parameter indicative of the effective quench condition of each sample is utilized to automatically adjust, by preselected preset amounts, the counting window for any given isotope relative to the observed energy spectrum for that isotope. Various methods and apparatus are described which, although suitable for optimizing counting conditions for both multiple-labeled and single-labeled test samples, are particularly effective in creating significantly improved isotope separations when dealing with multiple-labeled samples -- for example, a double-labeled sample containing tritium (.sup.3 H) and carbon-14 (.sup.14 C).
Abstract:
A radiation analyzer which measures radiation from a plurality of radiation sources in a single measurement cycle to distinguish between the radioactivity level received from a plurality of radiation sources. The radiation level of one of the sources may be known so that that source serves as a radiation standard with which to compare the other sources. Alternatively, the sources may all be known and the comparative radioactivity levels utilized to obtain information concerning some other parameter, such as external attenuation.
Abstract:
Gamma ray measuring apparatus having a multi-compartment sample holder incrementally advanced along the surface to a measuring station. The sample holder contains a plurality of sample containing vials in close mating relationship within the compartments, each compartment being provided with an aperture in the bottom thereof, the aperture being of smaller dimension than the cross-sectional dimension of the vial. A detector assembly at the measuring station has an elongated access port therein, the lower portion of the access port having a funnel-shaped entrance end with the upper portion thereof having a crystal detector in proximity thereto. An elevating rod passes through the aperture engaging the bottom surface of the vial to raise the vial guided by the compartment and the funnel-shaped entrance through the access port into the sample chamber adjacent the crystal detector for sample measurement. The elevating rod is made of a shielding material for shielding the crystal detector from rays emanating from samples within the sample holder. Provision is made for access to the well by means of a manual sample access port in alignment with the upper portion of the well. The port is plugged during operation of the apparatus in the automatic mode, and a special vial holder is provided for access to the well in a manual mode.
Abstract:
A vial transfer mechanism is provided for transferring radioactive samples from a sample changer to a radioactivity counting or measurement chamber via a bottom access conduit. Vials are lowered, either individually or as a group, from the sample changer into a sample-receiving carriage, which then moves along a horizontal conduit to a position underneath the measurement chamber. An elevator then lifts the sample from the carriage into the chamber. Light tightness is provided by equipping the carriage with O rings so that the chamber is not exposed to atmospheric illumination. The device is particularly useful for the simultaneous counting of two or more samples, where the samples are located in proximity to each other while in the sample changer, but must be spaced away from each other during radioactive measurement.
Abstract:
An automated method and associated apparatus is provided for transferring sample vials and like regularized objects from a rectilinear array past a counting station in seriatim order. The array is indexed along an X-axis in at least one tray, rows of the array are indexed out of the plane of the array tray along a Z-axis by a comb member into a bottomless carriage, and individual vials in the carriage are then indexed seriatim along a Y-axis past a counting station. Photoelectric sensors are provided to override portions of the indexing mechanism if no sample vials are present in array rows or individual compartments.
Abstract:
A sample changing and light sealing mechanism is illustrated and described for moving a sample from one vertical plane to another into a counting chamber while maintaining the light integrity within the chamber. Upon movement of the control arm toward a loading position, a cam on said control arm rotates an actuator wheel and arm to raise the elevator table from a counting position to within an elevator passageway and make a light tight seal at the chamber end of the passageway. The actuator wheel is stopped during further movement of the control arm which then opens an outer shutter over the passageway. The actuator wheel is then again rotated to raise the elevator still further so that the sample may be removed and replaced. Movement in the opposite direction reverses the sequence such that the chamber is at all times sealed against ambient light.
Abstract:
The continuous track has individual parallel track sections which are connected together by loops to form a single path for the loads. The conveyors move the loads by means of catches along the track. The loads are transferred at various points from one conveyor to another to change the speed of the loads so as to effect a slow movement of the loads in closely spaced relation past the radiation source.