Apparatus for maintaining field frequency control in a gyromagnetic instrument

Claim 2

In a gyromagnetic resonance apparatus having a polarizing magnetic field and a radio frequency magnetic field for resonating an unknown sample positioned within said fields, an improvement therein for maintaining field/frequency control during exchange of unknowns comprising: A. means for modulating the polarizing magnetic field with an audiofrequency magnetic field; B. means for controlling the frequency of the modulating means having first and second audiofrequency outputs; C. a probe member positioned within the polarizing magnetic field for holding an unknown sample mixed with an internal reference sample within the radio frequency magnetic field and an external control sample adapted to occupy the space occupied by said unknown sample mixed with the internal reference sample when it is removed from the probe; D. means for releasing the unknown sample and for positioning the control sample within the radio frequency magnetic field, said means provided with an activation circuit for selecting either the first or second frequency output of the control means, wherein the first output controls the modulating means when said unknown and reference samples are positioned in the radio frequency magnetic field to resonate said internal reference sample and the second output controlling the modulating means when the external control sample is positioned within the radio frequency magnetic field; and E. means responsive to an error signal created by a change in degree of resonance caused by fluctuations relative to the resonance conditions of the internal reference sample during sample analysis and the external control sample during sample changing for maintaining the field/frequency intensity ratio.

Claim 3

The improvement set forth in claim 1 wherein said means for modulating the polarizing magnetic field comPrises a set of coils controlled by a variable audio oscillator and a sweep oscillator, said audio oscillator having two frequency outputs and said sweep oscillator providing a sweep signal to resonate the unknown sample, one of said outputs being applied to the set of coils for modulating the polarizing magnetic field when the unknown sample is being measured, the other being applied to the said set of coils during sample exchange.

Claim 4

The improvement set forth in claim 1 wherein said probe member comprises: A. an upper and lower cylinder coaxially positioned, said upper cylinder having about its exterior an RF coil which produces a radiofrequency magnetic field; B. a control sample and holder therefor positioned in the lower cylinder and adapted for movement into the upper cylinder within the radiofrequency field; C. an unknown sample holder in the upper cylinder within the radiofrequency field and spaced apart from the control sample; and D. means for moving the control sample into the upper cylinder within the radiofrequency field when the unknown sample is removed.

Claim 5

The improvement set forth in claim 1 wherein said probe member comprises: A. an upper and lower spaced apart frame having coaxial openings therein; B. a bobbin positioned between said frames and having a coaxially aligned passageway in communication with said openings, said bobbin having positioned about its exterior a radio frequency coil; C. a cylinder depending from the lower frame in communication with the passageway and openings and having a base at its nondepending end and including two oppositely positioned slits extending through the cylinder; D. a cylindrical holder positioned within the cylinder and having an end with protrusions extending through the slits and at its other end containing the control sample; E. a spring positioned between the base and the holder end with the protrusions, said spring biasing said holder towards the bobbin passageway; F. a spacer mounted on top of said control sample; G. an unknown sample mounted on the spacer and within the bobbin and radio frequency coil; H. a pivotable hook means for holding said holder within the cylinder against the spring; and I. means for pivoting the hook to release the holder and force the control sample within the bobbin and the radio frequency coil.

Claim 6

The improvement set forth in claim 1 wherein the activation circuit of the release means includes: A. a divided variable resistor connected to a power supply at one end and grounded at the other; B. a switch connecting either of two points on the divided resistor with a third point; C. a resistor, coil and capacitor connected in series to the third point of the switch and to the ground of divided resistor; D. a relay for positioning the switch at either of said two points, said relay operable by said release means; and E. a tap between the coil and capacitor connected to said control means whereby the voltage taken from either of two points will select either the first or second output of said control means.

Claim 7

In a gyromagnetic resonance apparatus having a polarizing magnetic field and a radio frequency magnetic field for resonating an unknown sample positioned within said fields, an improvement therein for maintaining field/frequency control during sample exchange of unknown samples comprising: A. means for modulating the polarizing magnetic field with an audiofrequency magnetic field; B. means for controlling the modulating means having first and second audiofrequency outputs; C. a probe member positioned within the polarizing magnetic field for holding an unknown sample containing a internal reference sample and a control sample; D. a transmitter means for applying RF magnetic fields to said samples; E. switching means responsive to sample changes for operating an activation circuit; F. an activation circuit for selecting either the first or second frequency output of the control means wherein the first frequency output and the RF frequency field cause resonance of the internal reference sample and the second frequency output and RF frequency field cause resonance of said control sample; G. means responsive to an error signal created by a change in degree of resonance caused by fluctuations relative to the resonance conditions of the internal reference sample during sample analysis and the external control sample during sample changing for maintaining the field/frequency intensity ratio; and wherein said switching and activation circuit include: H. a photoelectric detector for detecting the presence of the unknown sample in the probe member; I. a relay connected to said detector; J. A divided variable resistor connected at one end to a power supply and grounded at its other; K. a first and second switch, said first switch for connecting and disconnecting the radio frequency to the control sample to create a radiofrequency magnetic field about said sample, said second switch connecting two points on the resistor; L. a resistor, coil and capacitor connected in series to the third point of said second switch and to the divided resistor ground; and M. a tap between the coil and capacitor connected to said control means whereby the voltage taken from either said two points will select either the first or second output frequency of said control means.

Claim 8

In a gyromagnetic resonance apparatus having a polarizing magnetic field and a radio frequency magnetic field for resonating an unknown sample positioned within said fields, an improvement therein for maintaining field/frequency control during sample exchange of unknown samples comprising: A. means for modulating the polarizing magnetic field with an audiofrequency magnetic field; B. means for controlling the modulating means having first and second audiofrequency outputs; C. a probe member positioned within the polarizing magnetic field for holding an unknown sample containing a internal reference sample and a control sample; D. a transmitter means for applying RF magnetic fields to said samples; E. switching means responsive to sample changes for operating an activation circuit; F. an activation circuit for selecting either the first or second frequency output of the control means wherein the first frequency output and the RF frequency field cause resonance of the internal reference sample and the second frequency output and RF frequency field cause resonance of said control sample; G. means responsive to an error signal created by a change in degree of resonance caused by fluctuations relative to the resonance conditions of the internal reference sample during sample analysis and the external control sample during sample changing for maintaining the field/frequency intensity ratio; and wherein said switching and activation circuit include: H. a photoelectric detector for detecting the presence of the unknown sample in the probe member; I. a relay connected to said detector; J. A divided variable resistor connected at one end to a power supply and grounded at its other; K. a first and second switch, said first switch for connecting and disconnecting the radio frequency to the control sample to create a radiofrequency magnetic field about said sample, said second switch connecting two points on the resistor; L. a resistor, coil and capacitor connected in series to the third point of said second switch and to the divided resistor ground; and M. a tap between the coil and capacitor connected to said control means whereby the voltage taken from either said two points will select either the first or second output frequency of said control means.

Claim 9

A gyromagnetic resonance apparatus comprising: A. a pair of spaced apart magnets for creating a polarizing magnetic field and having a power supply and magnetic flux stabilizer coils; B. an RF transmitter coupled through a bridge circuit to an RF coil for creating an RF magnetic field; C. a pair of modulation coils for modulating said polarizing magnetic field with an audiofrequency magnetic field and a sweeping magnetic field; D. a probe member positioned between said modulation coils, said probe holding the unknown sample mixed with a reference sample within the RF coil and a control sample adapted to be moved within the space previously occupied by the unknown sample when the unknown sample is removed; E. a sweep oscillator connected to the modulation coils for providing the sweeping magnetic field resonating said unknown and a variable oscillator having a first and second frequency output providing audiofrequency magnetic fields that cooperate with the Rf magnetic field to resonate the internal reference and external control samples respectively, connected to the modulation coil, said resonances causing an output from said bridge circuit having components corresponding to the frequency of the sweep oscillator and the first and second frequencies; F. a means for positioning the unknown sample within the RF field and for releasing the unknown sample and for positioning the control sample within the space previously occupied by said unknown in the RF field within the probe, said means including a circuit means connected to the variable oscillator for switching the oscillator to the first frequency output when the unknown sample is positioned within the RF field and for switching to the second frequency outputs of said oscillator when said external control sample is positioned within the RF field; G. a homodyne detector connected to said bridge circuit and RF transmitter for detecting only said first and second frequency output components and sweep frequency output component; H. a first phase sensitive detector connected to said homodyne detector and sweep oscillator for eliminating said first and second frequency output to form an absorption waveform of the sweep oscillator component of the resonance signal of the unknown sample; I. a recorder for recording said waveform; J. a second phase sensitive detector connected to said homodyne detector and variaBle oscillator for forming the dispersion waveform of said first and second frequency output; and K. a magnetic flux stabilizer connected to said second phase detector and to said magnetic flux stabilization coils responsive to an error signal being the output of the second phase sensitive detector and caused by fluctuations from the resonance conditions in the control sample and internal reference sample for stabilizing said polarizing magnetic field.

Claim 10

A gyromagnetic resonance apparatus comprising: A. a pair of spaced apart magnets for creating a polarizing magnetic field and having a power supply and magnetic flux stabilizer coils; B. an RF transmitter coupled through a bridge circuit to an RF coil for creating an RF magnetic field; C. a pair of modulation coils for modulating said polarizing magnetic field with an audiofrequency magnetic field and a sweeping magnetic field; D. a probe member positioned between said modulation coils, said probe holding the unknown sample mixed with a reference sample within the RF coil and a control sample adapted to be moved within the space previously occupied by the unknown sample when the unknown sample is removed; E. a sweep oscillator connected to the modulation coils for providing the sweeping magnetic field resonating said unknown and a variable oscillator having a first and second frequency output providing audiofrequency magnetic fields that cooperate with the Rf magnetic field to resonate the internal reference and external control samples respectively, connected to the modulation coil, said resonances causing an output from said bridge circuit having components corresponding to the frequency of the sweep oscillator and the first and second frequencies; F. a means for positioning the unknown sample within the RF field and for releasing the unknown sample and for positioning the control sample within the space previously occupied by said unknown in the RF field within the probe, said means including a circuit means connected to the variable oscillator for switching the oscillator to the first frequency output when the unknown sample is positioned within the RF field and for switching to the second frequency outputs of said oscillator when said external control sample is positioned within the RF field; G. a homodyne detector connected to said bridge circuit and RF transmitter for detecting only said first and second frequency output components and sweep frequency output component; H. a first phase sensitive detector connected to said homodyne detector and sweep oscillator for eliminating said first and second frequency output to form an absorption waveform of the sweep oscillator component of the resonance signal of the unknown sample; I. a recorder for recording said waveform; J. a second phase sensitive detector connected to said homodyne detector and variaBle oscillator for forming the dispersion waveform of said first and second frequency output; and K. a magnetic flux stabilizer connected to said second phase detector and to said magnetic flux stabilization coils responsive to an error signal being the output of the second phase sensitive detector and caused by fluctuations from the resonance conditions in the control sample and internal reference sample for stabilizing said polarizing magnetic field.

Claim 11

A gyromagnetic resonance apparatus comprising: A. a pair of spaced magnets for creating a polarizing magnetic field; B. an RF transmitter coupled through a bridge circuit to a first and second RF coil for creating two RF magnetic fields; C. a pair of modulation coils for modulating the polarizing magnetic field with an audiofrequency magnetic field and a sweeping magnetic field; D. a probe member positioned between the modulating coils, said probe arranged to hold an unknown sample mixed with a reference sample within said first RF coil and a control sample within said second RF coil; E. a sweep oscillator for resonating said unknown sample connected to the modulation coils and a variable oscillator having a first and second frequency output providing alternating magnetic fields that cooperate with the RF magnetic fields to resonate the internal reference sample and external control sample respectively, connected to said modulation coils, said resonances causing an output from said bridge circuit having components corresponding to the frequency of the sweep oscillator and the first and second frequencies; F. a first phase sensitive detector connected to said bridge for detecting an audio frequency component of the resonance signal of said unknown sample to which the audiofrequency from the sweep oscillator is applied as a reference signal; G. a photoelectric detector and light source for detecting the presence of the unknown sample in the probe; H. a relay connected to said photoelectric detector for actuating a first switch to connect the RF transmitter and second RF coil when the unknown sample is removed, a circuit means connected to the variable oscillator for switching the oscillator to said first frequency output when the unknown sample is positioned within the first RF coil and for switching to the second frequency output when said unknown sample is removed; I. a preamplifier and detector connected to said first switch for detecting the resonance signals of the control sample; and J. a second phase sensitive detector connected to said detector for selecting only the audiofrequency component of the resonance signals and a magnetic flux stabilizer responsive to an error signal being the output of the second phase sensistive detector created by a change in degree of resonance caused by fluctuations from the resonance conditions in the control sample and internal reference sample for controlling the polarizing magnetic field.

Claim 12

A gyromagnetic resonance apparatus comprising: A. a pair of spaced magnets for creating a polarizing magnetic field; B. an RF transmitter coupled through a bridge circuit to a first and second RF coil for creating two RF magnetic fields; C. a pair of modulation coils for modulating the polarizing magnetic field with an audiofrequency magnetic field and a sweeping magnetic field; D. a probe member positioned between the modulating coils, said probe arranged to hold an unknown sample mixed with a reference sample within said first RF coil and a control sample within said second RF coil; E. a sweep oscillator for resonating said unknown sample connected to the modulation coils and a variable oscillator having a first and second frequency output providing alternating magnetic fields that cooperate with the RF magnetic fields to resonate the internal reference sample and external control sample respectively, connected to said modulation coils, said resonances causing an output from said bridge circuit having components corresponding to the frequency of the sweep oscillator and the first and second frequencies; F. a first phase sensitive detector connected to said bridge for detecting an audio frequency component of the resonance signal of said unknown sample to which the audiofrequency from the sweep oscillator is applied as a reference signal; G. a photoelectric detector and light source for detecting the presence of the unknown sample in the probe; H. a relay connected to said photoelectric detector for actuating a first switch to connect the RF transmitter and second RF coil when the unknown sample is removed, a circuit means connected to the variable oscillator for switching the oscillator to said first frequency output when the unknown sample is positioned within the first RF coil and for switching to the second frequency output when said unknown sample is removed; I. a preamplifier and detector connected to said first switch for detecting the resonance signals of the control sample; and J. a second phase sensitive detector connected to said detector for selecting only the audiofrequency component of the resonance signals and a magnetic flux stabilizer responsive to an error signal being the output of the second phase sensistive detector created by a change in degree of resonance caused by fluctuations from the resonance conditions in the control sample and internal reference sample for controlling the polarizing magnetic field.