1. A scroll compressor, comprising:
a hermetic container, refrigerant flowing in and out of which;
a driving unit installed in the hermetic container to rotate a rotation axis;
an orbiting scroll fixed to the rotation axis and rotated with the rotation axis; and
a fixed scroll fixed to the hermetic container, engaged with the orbiting scroll to define a compression chamber, and compressing refrigerant by an interaction with the orbiting scroll, a discharge direction of a discharge space-side discharge hole heading from the compression chamber to the discharge space not corresponding to a discharge direction of a compression chamber-side discharge hole.
2. The scroll compressor of claim 1, wherein the discharge hole of the fixed scroll is formed like two or more stairs.
3. The scroll compressor of claim 1, wherein the discharge hole of the fixed scroll comprises a discharge inlet portion through which high pressure refrigerant flows in, a discharge outlet portion through which high pressure refrigerant flows out, the discharge outlet portion being eccentric to the discharge inlet portion, and a discharge connection portion making the discharge inlet portion and the discharge outlet portion communicate with each other.
4. The scroll compressor of claim 3, wherein the discharge inlet portion and the discharge outlet portion are formed vertically in an eccentric state, and the discharge connection portion is formed horizontally.
5. The scroll compressor of claim 3, wherein the discharge inlet portion and the discharge outlet portion comprise a bottleneck section where certain areas communicate with each other, and the discharge connection portion is omittable.
6. The scroll compressor of claim 3, wherein a sectional area of the discharge outlet portion is larger than a sectional area of the discharge inlet portion.
7. The scroll compressor of claim 3, wherein a flow direction length of the discharge outlet portion is larger than a flow direction length of the discharge inlet portion.
8. The scroll compressor of claim 5, wherein a sectional area of the bottleneck section is 0.5 to 0.8 times of the sectional area of the discharge outlet portion.
9. The scroll compressor of claim 7, wherein the flow direction length of the discharge outlet portion is larger than the flow direction length of the discharge inlet portion by over 1.2 times.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. An electromagnetic tracking system comprising
a magnetic field generating unit driven by a drive signal,
a field sensing unit having a sensing signal responsive to changing magnetic field the generating and sensing units being arranged to generate and to sense, respectively, an electromagnetic field in an arena of interest, and wherein at least one of said units is movable,
signal measurement and conditioning circuitry connected to said units to
(i) detect the drive signal and the sensing signal,
(ii) ratiometrically combine said signals to form a mutual inductance matrix, and
a processor operative with the mutual inductance matrix to determine coordinates of the movable unit.
2. The electromagnetic tracking system of claim 1, wherein said system drives the field generating unit with a controlled voltage drive line, and senses current in said line.
3. The electromagnetic tracking system of claim 1, wherein said field generating unit comprises
a plurality of independent field coils,
a multiplexer coupled to said coils for selecting any one of said coils, and
an amplifier coupled to said coils via the multiplexer, the amplifier measuring a current flowing through any of the coils selected by the multiplexer.
4. The electromagnetic tracking system of claim 1, further comprising a calibration transmitter, the calibration transmitter being fixed with respect to the field sensing unit for generating a fixed reference field sensed by said sensing unit.
5. The electromagnetic tracking system of claim 4, wherein the field sensing unit comprises n2 coils spanning n2 dimensions, and the calibration coil is positioned to couple signal into each of said coils.
6. The electromagnetic tracking system of claim 4, further comprising a current sensor that senses one or more currents induced in the generating unit by the drive signal and another current sensor senses current in the calibration transmitter, both said current sensors being coupled to a common amplifier thereby providing a common gain factor for all current measurements
7. An electromagnetic tracking system comprising
a magnetic field generating unit having at least one field generating coil driven by a drive signal,
a field sensing unit having at least one field sensing coil generating a sensing signal responsive to a changing magnetic field, said changing magnetic field including a position-dependent field produced by said magnetic field generating unit
the generating and sensing units being arranged to generate and to sense,
respectively, an electromagnetic field in an arena of interest, and wherein at least one of said units is movable,
signal measurement and conditioning circuitry connected to said units to
(i) synchronously sample and digitize drive signal data and sensing signal data for respective pairs of field generating and field sensing coils, cumulating the digitized data to form a raw signal matrix, and
(ii) determine a mutual inductance matrix from the raw signal matrix, and a processor that utilizes the mutual inductance matrix to determine coordinates of the movable unit.
8. The electromagnetic tracking system of claim 7, wherein the field sensing unit is fixed to a structure and the field generating unit is movable.
9. The electromagnetic tracking system of claim 7, wherein the processor normalizes the raw signal matrix with respect to drive signal and sensing unit coil coupling response.
10. The electromagnetic tracking system of claim 8, wherein the processor determines coordinates of the movable unit by approximating coordinates of the field sensing unit relative to the field generating unit, and iteratively adjusting the approximated coordinates to determine coordinates of the movable unit.
11. The electromagnetic tracking system of claim 7, wherein the drive signal is any of a drive current or a drive voltage.
12. An electromagnetic tracking system comprising
a magnetic field generating unit driven by a drive signal,
a field sensing unit having a sensing signal responsive to a changing magnetic field, said changing magnetic field including a position-dependent field produced by said magnetic field generating unit,
the generating and sensing units being arranged to generate and to sense, respectively, an electromagnetic field in an arena of interest, and wherein at least one of said units is movable,
signal measurement and conditioning circuitry connected to said units to sample and digitize signal data for the field generating and field sensing units,
a distorter having a known structure disposed at a selected location in the arena of interest, and
a processor operative on the sampled and digitized signal data to determine relative coordinates and orientations of said field generating or field sensing unit, said processor modeling the distorter and the generating and sensing units to generate modeled signal data and fitting said modeled signal data to measured signal values to determine coordinates and orientations of said field generating and field sensing units.
13. An electromagnetic tracking system comprising
a magnetic field generating unit and a magnetic field sensing unit, at least one said units being movable relative to the other, the sensing unit having a sensing signal responsive to a changing magnetic field produced by said magnetic field generating unit
the generating and sensing units being arranged to generate and to sense, respectively an electromagnetic field in an arena of interest,
signal measurement and conditioning circuitry connected to said units to sample and condition field generating and field sensing signal values
a processor operative on sampled and conditioned signal values to determine relative position and orientation of said units
wherein the signal measurement and conditioning circuitry includes a common gain stage amplifier connected to plural coils and a high precision analog to digital converter that converts amplified coil signals to high precision digital values such that coil outputs over a work arena may be digitally processed without patching or conversion of gains in different regions of the work arena.
14. An intra-operative imaging and tracking system for guiding a surgical tool during a surgical procedure performed on a patient, comprising
a fluoroscope having an x-ray source and an imaging assembly, said source and imaging assembly being movable about the patient to generate a plurality of two-dimensional x-ray images of the patient from different views,
a magnetic tracker having a field generating unit driven by a drive signal to generate an electromagnetic field in an area of interest and a sensing unit that generates a sensing signal in response to said field, one of said units being secured against movement relative to said imaging assembly and the other unit being affixed to the surgical tool,
a magnetic field distorter secured against movement relative to said imaging assembly,
a signal measurement circuit for measuring said drive and sensing signals to generate measured signal data, and
a processor operative on said x-ray images and said measure signals, said processor modeling said field distorter and said generating and sensing units to derive modeled signal data and fitting said modeled signal data to said measured signal data to determine relative coordinates and orientations of said generating and sensing units, said processor further utilizing said x-ray images and said relative coordinates and orientations to determine position of the tool relative to the patient.
15. An intra-operative imaging and tracking system for guiding a surgical tool during a surgical procedure performed on a patient, comprising
a fluoroscope having an x-ray source and a detector, said x-ray source and detector being movable relative to the patient so as to generate a plurality of two-dimensional x-ray images of the patient from different views,
a magnetic tracker having a magnetic field generating unit driven by a drive signal to generate an electromagnetic field in an area of interest and a magnetic field sensing unit generating a sensing signal responsive to the electromagnetic field, one of said units being secured against motion relative to the detector and the other unit being affixed to the surgical tool,
a signal measurement circuitry electrically coupled to the tracker to measure said drive and sensing signals to form a matrix representing mutual inductance between said generating and sensing units,
a processor operative with said mutual inductance matrix and said x-ray images to determine coordinates of the unit affixed to the surgical tool and position of the surgical tool relative to the patient.
16. An electromagnetic tracking system comprising
a magnetic field generating unit driven by a drive signal,
a field sensing unit having a sensing signal responsive to a changing magnetic field, said changing magnetic field including a position-dependent field produced by said magnetic field generating unit,
the generating and sensing units being arranged to generate and to sense, respectively, an electromagnetic field in an arena of interest, and wherein at least one of said units is movable,
signal measurement and conditioning circuitry connected to said units to sample and digitize signal data for the field generating and field sensing units,
a distorter having a structure optimal for shielding one or more objects in the arena of interest, said distorted being disposed so as to substantially shield magnetic fields generated by said objects, and
a processor operative on the sampled and digitized signal data to determine relative coordinates and orientations of said field generating or field sensing unit, said processor modeling the distorter and the generating and sensing units to generate modeled signal data and fitting said modeled signal data to measured signal values to determine coordinates and orientations of said field generating and field sensing units.