Adapter cable for connecting a pulsoximetry sensor unit to a medical measuring device
First Claim
1. An adapter cable for connecting a pulsoximetry sensor unit to a medical measuring device,said pulsoximetry sensor unit comprising two antiparallel-connected, light-emitting elements for emitting light of different wavelengths into a part of the body supplied with pulsating blood and a photosensitive element for receiving light which has been allowed to pass through said part of the body supplied with pulsating blood, andsaid medical measuring device providing a pulsed supply signal, which supplies power to the light-emitting elements, and determining, on the basis of a signal produced by said photosensitive element, the oxygen saturation of the hemoglobin contained in the blood of the transilluminated part of the body,wherein said adapter cable comprises the following features;
- first and second lines for connecting the antiparallel-connected, light-emitting elements with supply terminals of the medical measuring device;
a third line for connecting one terminal of the photosensitive element to a measuring signal input of the medical measuring device;
a first grounding line for connecting another terminal of the photosensitive element to a reference potential terminal of the measuring device;
an electronic switch means, which is connected to said first and second lines and which, when activated, forms a shunt to at least one of the light-emitting elements, anda fault current detection circuit, which detects current flowing through the first grounding line and for activating the electronic switch means, if the current flowing through said first grounding line exceeds a limit value.
5 Assignments
0 Petitions
Accused Products
Abstract
An adapter cable is used for connecting a pulsoximetry sensor unit to a medical measuring device. The pulsoximetry sensor unit comprises, among other components, two antiparallel-connected, light-emitting diodes, which are activated alternatingly by a pulse current source of the medical measuring device. Between said pulsoximetry sensor unit and said medical measuring device, a plurality of grounding lines extend within the adapter cable. In the case of a short circuit between one of the two supply lines of the antiparallel-connected, light-emitting elements and one of the grounding lines, the fault current is caused to flow in the grounding lines to a first node in accordance with the present invention, said first node being adapted to be connected to a reference potential of the medical measuring device via a first resistor. The voltage drop across said first resistor will cause firing of a thyristor structure, if a limit value is exceeded, provided that the instantaneous control phase of the pulse current source of the medical measuring device can cause an activation of a predetermined element of the two light-emitting elements. The triggered thyristor circuit will cause an activation of a switch, which will establish a shunt to the light-emitting elements.
245 Citations
9 Claims
-
1. An adapter cable for connecting a pulsoximetry sensor unit to a medical measuring device,
said pulsoximetry sensor unit comprising two antiparallel-connected, light-emitting elements for emitting light of different wavelengths into a part of the body supplied with pulsating blood and a photosensitive element for receiving light which has been allowed to pass through said part of the body supplied with pulsating blood, and said medical measuring device providing a pulsed supply signal, which supplies power to the light-emitting elements, and determining, on the basis of a signal produced by said photosensitive element, the oxygen saturation of the hemoglobin contained in the blood of the transilluminated part of the body, wherein said adapter cable comprises the following features; -
first and second lines for connecting the antiparallel-connected, light-emitting elements with supply terminals of the medical measuring device; a third line for connecting one terminal of the photosensitive element to a measuring signal input of the medical measuring device; a first grounding line for connecting another terminal of the photosensitive element to a reference potential terminal of the measuring device; an electronic switch means, which is connected to said first and second lines and which, when activated, forms a shunt to at least one of the light-emitting elements, and a fault current detection circuit, which detects current flowing through the first grounding line and for activating the electronic switch means, if the current flowing through said first grounding line exceeds a limit value. - View Dependent Claims (8, 9)
-
-
2. An adapter cable for connecting a pulsoximetry sensor unit to a medical measuring device,
said pulsoximetry sensor unit comprising two antiparallel-connected, light-emitting elements for emitting light of different wavelengths into a part of the body supplied with pulsating blood and a photosensitive element for receiving light which has been allowed to pass through said part of the body supplied with pulsating blood, and said medical measuring device providing a pulsed supply signal, which supplies power to the light-emitting elements, and determining, on the basis of a signal produced by said photosensitive element, the oxygen saturation of the hemoglobin contained in the blood of the transilluminated part of the body, wherein said adapter cable comprises the following features: -
first and second lines for connecting the antiparallel-connected, light-emitting elements with supply terminals of the medical measuring device; a third line for connecting one terminal of the photosensitive element to a measuring signal input of the medical measuring device; a fourth line for connecting another terminal of the photosensitive element to a first node; a first resistor connecting the first node to a second node; a fifth line for connecting the second node to a reference potential terminal of the medical measuring device; an electronic switch means, which is connected at least to one of said first or second lines in such a way that, when said electronic switch means is activated, a flow of limit-exceeding current through the light-emitting elements will be prevented, and a fault current detection circuit, having an input side connected to said first and second nodes and having an output side connected to said electronic switch means and responsive to a voltage drop across the first resistor exceeding a limit value so as to activate said electronic switch means. - View Dependent Claims (3, 4)
-
-
5. An adapter cable for connecting a pulsoximetry sensor unit to a medical measuring device,
said pulsoximetry sensor unit comprising two antiparallel-connected, light-emitting elements for emitting light of different wavelengths into a part of the body supplied with pulsating blood, a photosensitive element for receiving light which has been allowed to pass through said part of the body supplied with pulsating blood, and a coding resistor whose resistance value is representative of the wavelength of the light emitted by one of said light-emitting elements, and said medical measuring device providing a pulsed supply signal, which supplies power to the light-emitting elements, and determining, on the basis of a signal produced by said photosensitive element, the oxygen saturation of the hemoglobin contained in the blood of the transilluminated part of the body, wherein said adapter cable comprises the following features: -
first and second lines for connecting the antiparallel-connected, light-emitting elements with supply terminals of the medical measuring device; a third line for connecting one terminal of the photosensitive element to a measuring signal input of the medical measuring device; a first grounding line for connecting another terminal of the photosensitive element to a first node; a coding resistor connection line for connecting one terminal of the coding resistor to a coding resistor terminal of the measuring device; a second grounding line for connecting another terminal of the coding resistor to the first node; a third grounding line constructed as an outer shield of the adapter cable and connected to the first node; a first resistor connecting said first node to a second node; a fifth line for connecting the second node to a reference potential terminal of the measuring device; an electronic switch means connected to said first and second lines and forming, when activated, a shunt for at least one of the light-emitting elements; and a fault current detection circuit, which responds to a voltage drop across the first resistor exceeding a limit voltage, so as to activate said electronic switch means. - View Dependent Claims (6, 7)
-
Specification