1. A casing mechanism comprising:
a casing;
a board support provided to the casing, and to which a first circuit board on which a first connector is mounted is fastened with a screw;
stress absorbing means provided to the casing, for fastening with a screw a second circuit board on which a second connector for connection to the first connector is mounted, in a state where the first connector and the second connector are connected to each other,
wherein the stress absorbing means comprises:
a first fixing lug including a screw hole perpendicular to a plane direction of the first circuit board; and
a second fixing lug provided at a position closer to the first connector and the second connector than to the first fixing lug, the second fixing lug having elasticity so that the second fixing lug can move in the plane direction of the first circuit board and having a screw hole in the same direction as the plane direction of the first circuit board.
2. The casing mechanism according to claim 1, wherein the second fixing lug is formed by cutting a part of the casing.
3. The casing mechanism according to claim 1, wherein the second fixing lug is formed with a separate part having an elasticity factor larger than that of the casing and is disposed integrally to the casing.
4. The casing mechanism according to claim 1, wherein the second fixing lug is constituted by another part other than the casing and is disposed rotatably around a support shaft perpendicular to the plane direction of the first circuit board.
5. A medical imaging apparatus comprising a casing mechanism, wherein the casing mechanism includes:
a casing;
a board support provided to the casing, and to which a first circuit board on which a first connector is mounted is fastened with a screw;
stress absorbing means provided to the casing, for fastening with a screw a second circuit board on which a second connector for connection to the first connector is mounted, in a state where the first connector and the second connector are connected to each other,
wherein the stress absorbing means comprises:
a first fixing lug including a screw hole perpendicular to a plane direction of the first circuit board; and
a second fixing lug provided at a position closer to the first connector and the second connector than to the first fixing lug, the second fixing lug having elasticity so that the second fixing lug can move in the plane direction of the first circuit board and having a screw hole in the same direction as the plane direction of the first circuit board.
6. The medical imaging apparatus according to claim 5, wherein the second fixing lug is formed by cutting a part of the casing.
7. The medical imaging apparatus according to claim 5, wherein the second fixing lug is formed with a separate part having an elasticity factor larger than that of the casing and is disposed integrally to the casing.
8. The medical imaging apparatus according to claim 5, wherein the second fixing lug is constituted by another part other than the casing and is disposed rotatably around a support shaft perpendicular to the plane direction of the first circuit board.
9. An ultrasound endoscope comprising a casing mechanism, wherein the casing mechanism includes:
a casing;
a board support provided to the casing, and to which a first circuit board on which a first connector is mounted is fastened with a screw;
stress absorbing means provided to the casing, for fastening with a screw a second circuit board on which a second connector for connection to the first connector is mounted, in a state where the first connector and the second connector are connected to each other,
wherein the stress absorbing means comprises:
a first fixing lug including a screw hole perpendicular to a plane direction of the first circuit board; and
a second fixing lug provided at a position closer to the first connector and the second connector than to the first fixing lug, the second fixing lug having elasticity so that the second fixing lug can move in the plane direction of the first circuit board and having a screw hole in the same direction as the plane direction of the first circuit board.
10. The ultrasound endoscope according to claim 9, wherein the second fixing lug is formed by cutting a part of the casing.
11. The ultrasound endoscope according to claim 9, wherein the second fixing lug is formed with a separate part having an elasticity factor larger than that of the casing, and is disposed integrally to the casing.
12. The ultrasound endoscope according to claim 9, wherein the second fixing lug is constituted by another part other than the casing and is disposed rotatably around a support shaft perpendicular to the plane direction of the first circuit board.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A gas analyzer, comprising:
an electromagnet that has spaced opposing magnetic poles forming an air gap with a magnetic field therebetween;
a power source for supplying cyclically variable electrical currentvoltage to said electromagnet;
a sample gas conduit and a reference gas conduit opening into said air gap, said sample gas conduit carrying a sample gas comprising a gas mixture to be analyzed, and said reference gas conduit carrying a reference gas having a known concentration of a predetermined gas component;
an exit conduit communicating with said air gap for removing an intermixed sample comprising said sample gas and said reference gas from said air gap with the magnetic field;
a pressure detecting microphone connected to said sample gas conduit and to said reference gas conduit, said pressure detecting microphone adapted for sensing gas pressures at a first predetermined acoustic measuring frequency and a second predetermined acoustic measuring frequency; and
electronics connected to said pressure detecting microphone to receive a first acoustic pressure signal component and a second acoustic pressure signal components, said electronics forming intermediate output signals comprising at least:
a first intermediate output signal describing content of a paramagnetic gas component in the sample gas, and
a second intermediate output signal including content data of a second gas component in the sample gas,
wherein said electronics comprise an amplifier with an input connected to receive said first acoustic pressure signal component and said second acoustic pressure signal component,
wherein said amplifier generates the first intermediate output signal and the second intermediate output signal,
wherein said electronics comprise a calculation unit with means to provide a first difference to describe the content of a gas component in said sample gas, and
wherein the first difference is calculated by subtracting the second intermediate output signal and the first intermediate output signal at their acoustic measuring frequencies.
2. A gas analyzer according to claim 1, wherein:
said pressure detecting microphone is adapted for sensing gas pressures at a third predetermined acoustic measuring frequency; and
said electronics receive a third acoustic pressure signal component, and form a third intermediate output signal including content data of a third gas component in the sample gas.
3. A gas analyzer according to claim 2, wherein said calculation unit comprises means to provide a second difference to describe the content of said third gas component in the sample gas, and wherein the second difference is calculated by subtracting the third intermediate output signal and the first intermediate output signal at their acoustic measuring frequencies.
4. A gas analyzer according to claim 3, wherein said calculation unit is adapted to provide at least two analyzer output signals starting from said first intermediate output signal, said first difference, and second difference, and wherein said analyzer output signals are proportional to the concentrations of three different gases present in said sample gas.
5. A gas analyzer according to claim 3, wherein said first acoustic measuring frequency, said second acoustic measuring frequency, and a third acoustic measuring frequency are selected to match for determination of the content of oxygen andor helium andor nitrous oxide.
6. A gas analyzer according to claim 2, wherein said first acoustic measuring frequency, said second acoustic measuring frequency, and a third acoustic measuring frequency are selected to match for determination of the content of oxygen andor helium andor nitrous oxide.
7. A gas analyzer according to claim 1, wherein said power source is a multi-frequency power source.
8. A gas analyzer according to claim 7, wherein said multi-frequency power source has components for supplying a chopped or alternating electrical currentvoltage to said electromagnet to produce magnetic field frequencies in said air gap of the electromagnet, said magnetic field frequencies respective at least to said first and second predetermined acoustic measuring frequencies.
9. A gas analyzer according to claim 1, wherein:
at least two pressure detecting microphones are connected to said sample as conduit and said reference gas conduit, and
wherein said electronics comprises at least a multi-channel electricalelectronic subtraction or addition unit that has amplifiers with inputs connected to receive at least two pairs of acoustic pressure signal components from the pressure detecting microphones, and which produce at least a subtractionaddition signal respective to each pair of acoustic pressure signal components at their acoustic measuring frequencies as the intermediate output signals.
10. A method for analyzing at least a paramagnetic gas component in a sample gas, the method comprising:
creating a cyclically variable magnetic field in an air gap positioned between opposing magnetic poles of an electromagnet;
flowing a sample gas along a sample gas conduit into said air gap;
flowing a reference gas with known concentration of a predetermined gas component along a reference gas conduit into said air gap;
intermixing said sample gas and said reference gas in said air gap under the effect of said cyclically variable magnetic field, wherein said intermixed gases are allowed to exit from said air gap through an exit conduit;
sensing gas pressures at a first predetermined acoustic measuring frequency from said sample gas conduit and from said reference gas conduit utilizing a pressure detecting microphone giving at least a first acoustic pressure signal component;
sensing gas pressures at a second predetermined acoustic measuring frequency from said sample gas conduit and from said reference gas conduit utilizing said pressure detecting microphone giving at least a second acoustic pressure signal component;
applying calculations to said first acoustic pressure signal component forming at least a first intermediate output signal describing content of a first gas component in the sample gas;
applying calculations to said second acoustic pressure signal component forming at least a second intermediate output signal including content data of a second gas component in the sample gas; and
calculating a first difference to describe the content of another gas component in said sample gas,
wherein the first difference is calculated by subtracting the second intermediate output signal and the first intermediate output signal at their acoustic measuring frequencies,
and wherein the first intermediate output signal and the second intermediate output signal generated by an amplifier from said first acoustic pressure signal component and said second acoustic pressure signal component.
11. A method according to claim 10, further comprising:
sensing gas pressures at a third predetermined acoustic measuring frequency from said sample gas conduit and from said reference gas conduit utilizing said pressure detecting microphone giving at least a third acoustic pressure signal component; and
applying calculations to said third acoustic pressure signal component or components forming at least a third intermediate output signal including content data of a third gas component in the sample gas.
12. A method according to claim 11, further comprising:
selecting one of said second acoustic measuring frequency and said third acoustic measuring frequency that has a higher frequency for measuring the concentrations of oxygen and a gas or gases other than oxygen.
13. A method according to claim 12, wherein said second acoustic measuring frequency is selected to be in the order of 2000 Hz for determining the concentration of nitrous oxide as said second gas component, and
wherein said third acoustic measuring frequency is selected to be in the order of 2450 Hz for determining the concentrations of helium third gas component.
14. A method according to claim 11, further comprising:
one of subtracting and adding the third acoustic pressure signal component at said third acoustic measuring frequency from or to each other resulting to said third intermediate output signal.
15. A method according to claim 14, further comprising attaining the concentration of the third gas component from a second difference,
wherein the second difference is calculated by subtracting the third intermediate output signal and the first intermediate output signal at their acoustic measuring frequencies.
16. A method according to claim 10, further comprising:
selecting one of said first acoustic measuring frequency and said second acoustic measuring frequency that has a higher frequency for measuring the concentrations of oxygen and a gas or gases other than oxygen.
17. A method according to claim 16, further comprising:
selecting said first acoustic measuring frequency to be at a maximum 300 Hz for determination of the concentration of oxygen as said first gas component in the sample gas;
selecting said second acoustic measuring frequency to be in the order of 2200 Hz for determining the concentrations nitrous oxide as said second gas component; and
selecting said third acoustic measuring frequency to be in the order of 2450 Hz for determining the concentrations of helium as said third gas component.
18. A method according to claim 10, further comprising:
one of subtracting and adding the first acoustic pressure signal component at said first acoustic measuring frequency from or to each other resulting to said first intermediate output signal; and
one of subtracting and adding the second acoustic pressure signal component at said second acoustic measuring frequency from or to each other resulting to said second intermediate output signal.
19. A method according to claim 18, further comprising:
attaining the concentration of the first gas component from said first intermediate output signal; and
attaining the concentration of the second gas component from the first difference.
20. A method according to claim 10, wherein the first acoustic pressure signal component at said first acoustic measuring frequency provides said first intermediate output signal, and wherein the second acoustic pressure signal component at said second acoustic measuring frequency provides said second intermediate output signal.
21. A method according to claim 20, wherein the third acoustic pressure signal component at said third acoustic measuring frequency provides said third intermediate output signal.