The present invention relates to a blood testing machine, and it more particularly relates to a machine which performs a plurality of different tests on a blood sample.
Medical doctors of today make use of many different techniques for diagnosing and controlling disease. One such technique is blood analysis, which has become more important with the advent of the modern hospital laboratory and the extensive research into human biochemistry. However, even though sophisticated procedures and apparatus have been developed for analyzing blood, the problem still remains of unwanted delays in obtaining the results of the blood tests. Thus, it would be highly desirable to have a machine for quickly and efficiently analyzing a patient's blood in the patient's room, thereby eliminating the time delay in transporting a blood sample to the hospital laboratory for analysis by the ordinarily overworked laboratory technicians. Also, it would be highly desirable to have such a machine which could repeatedly draw blood from a patient without repeated venepunctures and their accompanying trauma to the patient. In this regard, a needle portion of the input device to the machine would remain intravenous for as long as the physician deems necessary. In this way, a nonlaboratory attendant, such as a nurse, could repeatedly operate such a machine to test a patient's blood periodically, whereby the nurse would be alerted to any change in the patient's condition and thus be forewarned of an oncoming crisis, such as a heart attack. Moreover, it would be desirable to have such a machine which would be small in size and portable in nature, so that it could be used, if desired, in a vehicle, such as an ambulance.
Therefore, it is the principal object of the present invention to provide a new and improved blood testing machine.
It is further object of the present invention to provide a new and improved blood testing machine which can quickly analyze a patient's blood in the patient's room.
Another object of the present invention is to provide a new and improved blood testing machine which remains intravenous for as long as the treating physician deems necessary and which causes a blood sample to be drawn from the patient so that the machine can perform a plurality of different tests on the blood sample.
A further object of the invention is to provide a new and improved technique for separating blood serum from a blood sample.
Briefly, the above and further objects are realized in accordance with the present invention by providing a blood testing machine which draws a blood sample into the machine and performs a plurality of different tests on the blood sample. The machine of the present invention includes a suction device which causes the blood sample to be drawn into the machine, an input control device for determining the amount of blood withdrawn in proportion to the number of tests to performed, a pair of electrically energized electrodes for coagulating the blood, a dialyzer for separating the blood solids from the blood serum, a device for automatically diverting the serum into a preselected number of testing components which test the serum by techniques, such as laser spectroscopy.
The invention, both as to its organization and method of operation, together with further objects and advantages thereof will best be understood by reference to the following detailed description taken in connection with the accompanying sheets of drawings, wherein:
FIG. 1 is an elevational view, with portions thereof broken away for illustration purposes, of the blood testing machine of the present invention;
FIG. 2 is an enlarged, face view of the control panel for the machine of FIG. 1;
FIG. 3 is a cross-sectional, enlarged view of the left-hand side of the input control device for the machine of FIG. 1;
FIG. 4 is an enlarged, plan view in cross section of the input control device of FIG. 1 taken substantially along the line 4--4 thereof;
FIG. 5 is a fragmentary, cross-sectional view of a porting on the right-hand side of the input control device of FIG. 4 taken substantially along the line 5--5 thereof;
FIG. 6 is an enlarged, fragmentary detail view in cross section of the input control device of FIG. 4 taken substantially along the line 6--6 thereof;
FIG. 7 is an enlarged, plan view in cross section of the front end portion of the machine of FIG. 1 taken substantially along the line 7--7 thereof;
FIG. 8 is an enlarged elevational view in cross section of the front end portion of the machine of FIG. 1 taken substantially along the line 8--8 thereof;
FIG. 9 is an enlarged, cross-sectional view of the machine of FIG. 1 taken substantially along the line 9--9 thereof;
FIG. 10 is an enlarged, elevational view in cross section of the dialyzer and main vacuum pump components of the machine of FIG. 1;
FIG. 11 is an enlarged, cross-sectional view of the dialyzer of FIG. 10 taken substantially along the line 11--11 thereof;
FIG. 12 is an enlarged view of the machine of FIG. 1 taken substantially along the line 12--12 thereof;
FIG. 13 is a plan view of the diverter and combiner components of the machine of FIG. 1;
FIG. 14 is an enlarged, cross-sectional fragmentary view of the diverter component of FIG. 13 taken substantially along the line 14--14 thereof, portions of the diverter component being enlarged to a greater extent than other portions for illustration purposes;
FIG. 15 is an enlarged, cross-sectional view of the rod release mechanism of FIG. 1 taken substantially along the line 15--15 thereof;
FIG. 16 is an enlarged, perspective view of a member of the diverter of FIG. 14;
FIG. 17 is a fragmentary, enlarged view in vertical cross section of the combiner and readout components of the machine of FIG. 1;
FIG. 18 is a reduced-scale fragmentary plan view of the vacuum release mechanism of FIG. 17;
FIG. 19 is a schematic drawing of the control circuitry for the machine of FIG. 1; and
FIG. 20 is an enlarged cross-sectional view of another readout component constructed in accordance with the present invention.
Referring now to the drawings, and more particularly to FIG. 1 thereof, there is shown a blood testing machine 10 which embodies the principles of the present invention. The machine 10 generally comprises an input control device 12 which has a tubular needle 14 for inserting into the vein of a patient, and a portable unit 16 which includes suction and testing components for drawing a blood sample into the unit 16 and for subjecting the blood sample to a plurality of different preselected tests. The portable unit includes a suction and converter component 18, a dialyzer component 20, a main vacuum component 22, a diverter and combiner component 24, a readout component 26, a laser component 28, and a control unit 30. A tube 31 connects the input control device 12 to the portable unit 16 to convey the blood sample directly from the patient's vein to the unit 16 for testing purposes. However, it is to be understood that, if desired, the blood sample need not be taken directly from the patient's vein, and that the sample may instead be taken in the conventional manner and then drawn into the machine 10 via the needle 14 of the input control device 12. A tube 33 connects a bottle 35 containing a proteolytic cleaning fluid, such as acetone, to the input control device 12 for conveying the cleaning fluid through the system during a cleaning cycle of operation, which immediately follows a blood testing operation.
Referring now to FIGS. 1, 7, 8 and 9, in order to draw a blood sample from the patient via the input control device 12 and the tube 31 into the unit 16, the tube 31 is connected in fluid communication at a Y-junction 37 to a pair of tubes 39 and 41, which are relatively larger in diameter than the diameter of the tube 31, and a roller 43, which is mounted on a carriage 45, extends transversely across both of the tubes 39 and 41 and compresses them as the carriage 45 moves the roller 43 along the tubes 39 and 41 to evacuate the air therefrom. The volume of the tube 39 is slightly greater than the volume of the tube 31 to cause the blood sample to be drawn from the needle 14 of the input control device 12 to the junction 37. The tube 41 is longer than the tube 39 and has a volume which is sufficiently large to cause the blood sample to be drawn through the component 18 and into the dialyzer component 20. As best seen in FIG. 8, a piston-cylinder operated clamp 47 located near the junction 37 of the tube 31 alternately compresses one and then the other of the tubes 39 and 41. The clamp 47 normally compresses the tube 41, and thus the tube 39 causes the blood sample to be drawn from the patient into the tube 31 via the input control device 12. When the blood sample reaches the junction 37, the clamp 47 automatically switches to compress the tube 39 and open the evacuated tube 41 so that the blood sample enters the tube 41, which at its opposite end is connected in fluid communication with the dialyzer component 20.
A pair of platinum electrodes (not shown) are located in the interior of the tube 71 near the entrance to the dialyzer component 20 and are electrically energized to cause the blood to be coagulated so that the blood solids can be separated from the blood serum by the dialyzer component 20. If desired, additional pairs of electrodes may also be provided in the tube 41 and arranged in a spaced-apart manner to ensure uniform clotting of the blood. The electrodes traumatize the blood, and thus a clotting mechanism of the blood is triggered in the same manner that a wound triggers the clotting mechanism. It is to be understood that other devices as well can be used to separate the blood serum from the blood solids.
As best seen in FIGS. 1, 9, 11 and 12, a tube 49 is connected in fluid communication with the dialyzer component 20 to convey the unnecessary solid or cellular portion of the blood sample from the dialyzer component 20 and extends (FIG. 11) longitudinally along the component 18 above the tube 41 to a point (FIG. 1) almost midway between the ends of the component 20, at which point the tube 41 bends (FIG. 9) and extends through an opening in the rear wall of the component 20 and extends (FIG. 12) along the outside of the backwall of the component 20 to a waste bottle 51 which rests on the top wall of the component 22. In order to draw the unnecessary cellular portion of the blood sample from the dialyzer component 20, carriage 45 rolls along and compresses the tube 49 as the carriage 45 returns to its initial position near the clamping device 47, whereby a vacuum is created in the tube 49 to draw the waste material from the dialyzer component 20. For the purpose of drawing the waste material along the tube 49 which extends along the outside of the component 20, a tube 53 is connected in fluid communication to the bottle 51 and extends from the bottle 51 across the top of the dialyzer component 20 through an opening in the top wall of the component 18 and extends the length thereof above the tube 39. Thus, the carriage 45 compresses the tube 53 and thus causes a vacuum to be formed therein to evacuate the waste bottle 51, whereby the waste material is drawn into the bottle 51.
A tube 55 is connected to the serum outlet of the dialyzer component 20 to convey the serum from the dialyzer component 20 to the diverter and combiner component 24 under the control of the main vacuum component 22. The diverter portion of the component 24 diverts the blood sample into a number of different combining chambers in accordance with the number of tests to be performed. Chemical reagents are automatically added to the blood serum in each of the combining chambers. The readout component 26 receives the mixtures of serum and reagents and filters the mixtures. The filtrates are subjected to laser spectroscopy by means of laser beams from the laser component 28 to produce secondary radiations which are then graphically displayed on a graph (not shown), which may be an integral part of the blood testing machine 10 or which may be a separate component. The intensity of the secondary radiation from each of the filtrates closely follows "Beer's Law," and thus is proportional to the concentration of the blood component being tested.
In operation, an ON-OFF switch 57 located on a control panel 59 (FIG. 2) is switched to its ON position to commence the operation of the machine 10. The needle 14 is inserted into the vein of the patient, and the attendant then selects the test or tests to be performed on the patient's blood by pushing one or more of the series of 10 different selection buttons 60, which are arranged in a circle on the test panel 59. Once the machine 10 is thus programmed, a start button 62 located at the top of the dialyzer component 20 is pushed to initiate a cycle of operation. Thus, the blood is drawn from the patient through the needle 14 and the input control device 12 via the tube 31 into the component 18. After the blood sample is drawn and leaves the device 12, cleaning fluid from the bottle 35 via the tube 33 is drawn through the input control device 12 into the tube 31, so that the cleaning fluid can follow the blood sample through the various components of the machine 10 for cleaning purposes.
As the blood sample reaches the junction 37 at the end of the tube 31, the clamping device 47 switches to compress the tube 39 and open the tube 41, whereby the blood sample enters the evacuated tube 41. The blood sample is then subjected to the pair of electrically energized electrodes in the tube 41 to coagulate the blood sample. The blood serum is then separated from the solid portion of the blood sample by means of the dialyzer component 20 and conveyed via the tube 55 to the diverter and combiner unit 24. The blood serum sample is then diverted into a preselected number of combining chambers in accordance with the number of tests to be performed, and the necessary chemical reagents are combined with the blood serum in the combining chambers to form precipitates. The precipitates are then filtered out and analyzed by laser spectroscopy, the results being displayed graphically.
Considering now the input control device 12 in greater detail with reference to FIGS. 3, 4, 5 and 6, of the drawings, the device 12 includes an elongated hollow housing member 66, a nose member 68 which is welded to the member 66 by a peripheral weld 70, and a housing 72 mounted on the side of the member 66. The device 12 is composed of a suitable metal, but it may also be molded of a suitable plastic material. A pair of U-shaped strap holders 74 and 76 are connected respectively to the member 66 and the housing 72 for the purpose of receiving and retaining a strap (not shown) so that the device 12 can be held in place on the patient. At least a portion of the device 12 is intended to be a disposable item so that a fresh sterilized unit can be used for each patient.
As best shown in FIG. 3, a passageway 78 in the nose member 68 communicates with a passageway 81 which extends the length of the upper portion of the member 66 and which is connected in fluid communication with the tube 31 to convey the blood sample from the needle 14 to the tube 31. A passageway 83 in the lower portion of the member 66 extends the length of the member 66 and communicates with the passageway 78 in the nose member 68 to convey the cleaning fluid from the tube 33 to the passageway 78 and thus to the passageway 81 and the tube 31. A connector 83 extends from the front end of the nose member 68 for sealably receiving an enlarged hollow end portion 87 of the hollow needle 14 to connect the needle 14 in fluid communication with the passageway 78 in the nose member 68. A ball valve 89 is located in the nose member 68 in the junction between the passageway 78 and the passageway 81 to permit the blood sample and the cleaning fluid to flow from the passageway 78 into the passageway 81, but fluid cannot flow from the passageway 81 into the passageway 78, whereby fluids are prevented from entering the vein of the patient. A ball valve 91 is disposed in the nose member 68 at the junction between the passageway 78 and the passageway 83 to permit the cleaning fluid to flow from the passageway 83 into the passageway 78, and the ball valve 91 also prevents the blood sample from entering the passageway 83.
A needle valve 93 includes a thin plastic rod 94 which extends through an opening in the member 66 and into the passageway 78 of the nose member 68, and which in its closed position extends into the interior of the needle 14 and extends out the point of the needle by a slight distance to prevent any blood from entering the needle. As shown in FIG. 3, when the valve 93 is open, the rod 94 of the needle valve 93 is retracted so that its distal end is located in the passageway 78 to permit the blood sample to flow into the passageway 78. A block 98 is connected to the rear end of the rod 94 to control the movement of the rod 94 and is slidably mounted in a bore 101 in the member 66. The needle valve 93 also includes a spring 103 which is located in the bore 101 and biases the block 98 away from the front end of the housing member 66 to cause the needle valve 93 to the biased in its open position. A rod 98A extends from the rear end of the block 98 through a central hole in a removable retainer 104, which is threaded into the rear end of the housing member 66, and when the needle valve 93 is disposed in its open position, the rod 98A compressingly engages the tube 33 to shut off the tube 33 so that the cleaning fluid is prevented from entering the passageway 83 unless and until the valve 93 is moved out of its open position.
In order to close the needle valve 93, as best shown in FIG. 4, a pair of rods 105 and 106 are connected to and extend from opposite sides of the block 98 through the respective elongated openings 107 and 108 in the housing member 66. A timing device generally indicated at 109 in the housing 72 normally maintains the needle valve 93 in its closed position against the force of the spring 103 as shown in FIG. 5, but the device 109 permits the needle valve 93 to snap back to its open position at the beginning of a testing cycle of operation. The device 109 closes the needle valve 93 against the force of the number of tests to be performed. In this regard, the needle valve 93 remains in its open position for a period of time which is proportionate to the number of test-selecting buttons 60 which are selected and depressed by the attendant. For this purpose, a direct-current electric motor 111 which is disposed within the housing 72 drives a timing belt 113. As shown in FIG. 5, the valve 93 is disposed in its closed position, and a gear tooth 115 on the belt 113 engages the rod 105 and maintains the rod 105 in its extreme frontmost position during the interval of time in which the needle valve 93 is closed. However, once the machine 10 is programmed by depressing the buttons 60 and the start switch 62 is depressed, the electric motor 111 drives the timing belt 113 in a counterclockwise direction as seen in FIG. 5 so that the gear 115 is cammed away from the rod 105 to permit the block 98 to snap back to its normal position as seen in FIGS. 3 and 4. The motor 111 is driven at a rate of speed which is inversely proportionate to a number of selection buttons 60 which have been selected and depressed. In other words, with a greater number of depressed buttons 60, the motor 111 drives the timing belt 113 at a correspondingly slower speed, whereby the valve 93 remains open for a proportionately longer time to withdraw a proportionately greater amount of blood from the patient. Once the gear tooth 115 commences its forward motion, the tooth 115 engages the rod 105 to move it in a forward direction against the force of the spring 103. A switch 117 is engageable by the lower end portion of the gear tooth 115 to cause the motor 111 to abruptly stop the timing belt 113 once the valve 93 reaches its closed position. The gear 115 normally maintains the block 98 in its extreme forward position, thereby to maintain the needle valve 93 in its closed position.
A drive shaft 119 of the motor 111 and a capstan or sleeve 120 surrounding and fixed to the drive shaft drives the timing belt 113 which is wrapped about and stretched between the capstan 120 and another capstan 121 which is rotatably mounted on a stub shaft 123. In order to permit the rod-engaging portion of the tooth 115 to readily move past the capstan 121, as shown in FIG. 6, the capstan 121 has a depressed or reduced portion 125, which receives the tooth 115 as it moves past the capstan 121. The capstan 120 has a similar depressed portion (not shown) to permit the rod-engaging portion of the tooth 115 to pass by the drive shaft 119. The electrical connections for the motor 111 and a pair of wires 126 for the switch 117 are connected to the control unit 30 via a cable 127.
Considering now the clamping device 47 in greater detail with reference to FIGS. 1, 7 and 8 of the drawings, the clamping device 47 includes a lever 120 which is pivotally mounted at 122 and extends transversely over the tubes 39 and 41 which are disposed on opposite sides of the pivot point 122. A spring 124 is connected to an end 125 of the lever 120 to bias it into compressing engagement with the tube 41 to shut off the tube 41, the tube 39 on the opposite side of the pivot point 122 being normally in an open condition. A piston cylinder assembly 126 has a piston rod 127 which is connected to an opposite end 129 of the lever 120 to pivot the lever 120 in a clockwise direction as seen in FIG. 8 until the lever 120 compressingly engages the tube 39 to shut off the tube 39 and to open the tube 41.
Considering now the suction and converter component 18 with reference to FIGS. 1 and 9 of the drawings, the tubes 39 and 41 are supported by the respective horizontal spaced-apart, coplanar plates 131 and 133 which extend from and are supported by the respective vertical sidewalls 135 and 137 of the component 18. A pair of horizontal, coplanar spaced-apart plates 139 and 141 are supported by the respective sidewalls 135 and 137 and are disposed above the plates 131 and 133, respectively, to cause the roller 43 to compressingly engage the tubes 39 and 41 as the roller 43 moves toward the dialyzer component 20, whereby the roller 43 rolls along the tubes 39 and 41 and compresses them. The carriage 45 includes a triangularly shaped plate 142 which has a backwardly sloping guide slot 143 through which extends a reduced portion 145 of the roller 43 so that when the carriage 45 moves in a direction away from the dialyzer component 20, the roller 43 is permitted to roll along the upper surfaces of the plates 139 and 141 whereby to compress the upper tubes 49 and 53 against a top wall 147 of the component 18. As shown in FIG. 1, a downwardly turned end portion (not shown) of the plate 141 near the component 20 cause the roller 43 to be guided upwardly when the carriage 45 reverses its direction of movement and moves away from the component 20 to position the roller above the plates 139 and 141.
A gear 152 is rotatably connected to the plate 142 of the carriage 45 by means of a rivet 154. A pair of vertically spaced racks 156 and 158 extend for the length of the component 18 and mesh with the gear 152, whereby the carriage can roll along the racks 156 and 158. The rack 156 is connected to the underside of the plate 133, and the rack 158 is connected to a bottom wall 160 of the component 18. A direct-current electric motor 162 is mounted on the carriage plate 142 and drives the gear 152 by a suitable gear train (not shown).
As shown in FIG. 1, a limit switch 164 is supported by the plate 133 near the end of the tube 39 and is actuated by the carriage plate 142 to cause the clamping device 47 to switch from its normal position as the carriage 45 moves toward the dialyzer component 20 and rolls past the end of the tube 39. A switch 166 is supported by the bottom wall 160 beyond the downwardly turned end portion 149 of the guide plate 133 so that when the carriage plate 142 actuates the switch 166, it causes a reversal of electrical power to the electric motor 162 thereby to reverse the direction of movement of the carriage 45.
Referring now to FIGS. 1, 10, 11 and 12, the start button 62 comprises a rod 172 which is spring-loaded at its bottom end by means of a coil spring 174 (FIG. 10) and which has an electrical switch 62A mounted on the top wall of the component 20 and actuated by the rod 172 to start a cycle of operation. In order to retain the rod 172 in its depressed condition, a catch member 176, which is a rod bent in the shape of a rectangle, is urged into engagement with the rod 172 by means of a pair of springs 178 and 179 (FIG. 11) stretched between the respective rings 181 and 183 of the respective side portions 185 and 187 of the catch member 176 and an end wall 189 of the component 18. A notch 191 in the rod 172 receives an end portion 193 of the catch member 176, when the rod 62 is depressed, to maintain the rod 172 in its depressed condition. As shown in FIG. 1, when the carriage 45 returns to its original position, an opposite end portion 195 of the catch member 176 is moved by the carriage plate 142 of the carriage 45 to move the end portion 193 of the catch member 176 out of engagement with the notch 191 to permit the spring 174 to return the rod 172 to its initial position. Thus, the carriage plate 142 moves the catch member 176 to cause the switch 62A to turn off the power to abruptly stop the carriage 45. As a result, the carriage 45 comes to rest at a position where the roller 43 is located beyond the end portion of the guide plates 139 and 141 near the sidewall 170 so that the roller then returns to its normal position in the lower end of the slot 143 in the plate 142. When the start button 62 is depressed to start a cycle of operation, the bottom 62 must be held in a fully depressed condition until the carriage 45 begins to move toward the dialyzer component 20 to permit the catch member 176 to move into engagement with the notch 191. In order to slidably mount the catch member 176, the side portions 185 and 187 of the catch member 196 are slidably supported by a plurality of the respective brackets 197 and 199 which are supported by the top wall 147 of the component 18.
Considering now the dialyzer component 20 is greater detail, with reference to FIGS. 1, 10 and 11 of the drawings, the component 20 separates the clotted blood from the blood serum so that the blood serum can be subjected to the desired tests. It should be understood that, if desired, rather than utilizing the electrodes and the dialyzer component 20, the blood serum may be obtained directly by separating the blood serum from the unnecessary cellular blood solids by conventional means. A ball check valve 200 is disposed in the tube 41 which is connected to an inlet 202 of a dialyzer unit 204 for separating the clotted blood solids from the blood serum. The ball check valve 200 permits the clotted blood to enter the dialyzer unit 204 and prevents any flow of fluid in the reverse direction. Thus, the check valve 200 prevents partially clotted blood from flowing back toward the input control device 12 and thus the patient. The dialyzer unit 204 includes a helical semipermeable tube 205 which is connected in fluid communication between the inlet 102 and an outlet 206, and a tube 208 which concentrically and sealably surrounds the semipermeable tube 205. The tube 208 is connected in fluid communication with an outlet 210 which in turn is connected in fluid communication with the tube 55. The suction tube 55 draws the blood serum through the semipermeable tube 205 into the concentric tube 208 and out the tube 55, whereby the blood serum id drawn from the dialyzer component 20 and is transferred to the component 24. The larger unnecessary cellular portion of the blood does not pass through the semipermeable tube 208, but instead it is conveyed to the tube 49 via a ball check valve 212 which permits the cellular portion of the blood to leave the dialyzer unit 204 and prevents a reverse flow the cellular portion of the blood from the tube 49 to the dialyzer unit 204.
The unnecessary cellular portion of the blood sample is drawn from the dialyzer unit 204 into the evacuated tube 49 as a result of the roller 43 compressing the tube 49 and forcing the air therefrom. In order to draw the cellular portion of the blood from the tube 49 to the waste bottle 51, the roller 43 also compresses the longer tube 53 to force the air therefrom and thus to withdraw the air from the bottle 51, which is connected in fluid communication with the tube 53.
Considering now the main vacuum component 22 in greater detail with reference to FIG. 10 of the drawings, the main vacuum unit 22 supplies the necessary vacuum to draw the blood serum from the dialyzer component 20 to the diverter component 24 and the readout component 26. Since the blood serum is not as unstable as whole blood, the suction produced by the main vacuum component 22 need not treat the blood serum as gently as the suction component treated the whole blood. Moreover, if desired, a conventional vacuum pump may be used in place of the component 22.
As shown in FIG. 1, the vacuum pump component 22 includes a plunger 214 which extends into the component 18. In FIG. 1, the plunger 214 is shown in the normal position, and it is shown in its fully retracted position in FIG. 10. The plunger 214 is moved from its normal position to its retracted position by the carriage plate 142 to activate the vacuum pump component 22. One end of a hollow piston rod 216 is connected to an end plate 218 of the plunger 214, and the opposite end of the hollow piston rod 216 is connected to a piston head 221 which is slidably mounted within an elongated chamber 223. A return spring 225 is positioned between the end plate 218 of the plunger 214 and the vacuum chamber 223 to bias the plunger 214 to its normal position, as shown in FIG. 1, the spring 225 causing the plunger 214 to move extensively toward the left as seen in FIG. 1 as the carriage 45 returns to its initial position.
A ball valve 229 is positioned in the hollow rod 216 at an opening in the end wall of the piston head 221 to permit air to flow from the interior of the chamber 223 into the hollow piston rod 216 and enter the atmosphere via a vent 231 in the portion of the piston rod 216 extending outside of the chamber 223. Thus, as the plunger 214 retracts due to the carriage 45, a tube 223 which is connected in fluid communication between the evacuated chamber 223 and other components of the machine 10 via a ball check valve 235, provides the necessary suction to draw the blood serum through the remaining components to the readout component 26. The valve 235 prevents air from entering the interior of the evacuated chamber 223 and permits air to escape during the initial movement of the piston head 221 to evacuate the chamber 223.
In order to energize the diverter component 24 to receive the blood serum, a toggle switch 236 is actuated by an abutment 236b as the plunger 214 is moved to its retracted position, and the switch 236 is opened by an abutment 236a during the return of the plunger 214 to its initial position.
Considering now the diverter component 24 in greater detail with reference to FIGS. 1, 13, 14, 15 and 16, the selection buttons 60 each include a rodlike extension 237 (FIG. 1), which is similar to the start button 62 and which extends into the diverter component 24 to control its operation. As best seen in FIG. 13, the diverter component 24 includes a valve assembly 239 for conveying the blood serum to a combining assembly 241 which surrounds the valve assembly 239 and which comprises a plurality of individual combining units 243. The diverter component further includes a plurality of individual valve units 245, which are controlled by the rods 237, for selectively connecting the valve assembly 239 in fluid communication with the combining units 243. The rods 237 are reciprocably mounted in the valve units 245, and the upper ends of the rods 237 project from the control panel 59 to provide the selection buttons 60. The lower ends of the rods 60 extend into the valve units 245.
As shown in FIG. 15, in order to retain the rods 60 in a depressed position during a testing cycle of operation, there is provided an electromagnetic release mechanism 247 having a plurality of individual catchplates 249 which are slidably mounted on a baseplate 250. A plurality of springs 252 extending between the catchplates 249 and a plurality of electromagnets 254 bias the catchplates 249 against the rods 237. A plurality of slots 256 in the rods 237 receive the catchplates plates 249 when the rod is moved into its downward position, whereby the catchplates 249 retain the depressed rods in their downward position. As best seen in FIG. 14, a plurality of springs 258 surround the rods 237 above the valve unit 245, and a plurality of springs 260 are disposed within the valve units 245 at the bottom ends of the rods 237 to bias the rods 237 in their upper position where the buttons extend above the control panel, whereby when the magnets 254 are energized to retract the catchplates 249 against the force of the springs 252, the springs 258 and 260 of the depressed rods 237 cause the depressed rods to return to their upper initial position. It is to be understood that the valve units 245 as illustrated in FIG. 14 are shown in an enlarged scale as compared to the valve assembly 239 and the selection and combining assembly 243.
The valve assembly 239 generally comprises a cylindrical housing valve-seat member 262 which has a conical-shaped chamber 264, and a conical-shaped valve member 266 which is urged via a compression spring 268 into a closed position in the chamber 264 to seal an inlet 271 which is connected in fluid communication with the tube 55. A plurality of passageways 275 are disposed below the valve member 266 in a lower base portion 273 of the housing member 262 and communicate with the conical-shaped chamber 264 to convey the blood serum from the tube 55 to a plurality of passageways 277 which are located in the housing member 262 and which are connected in fluid communication with corresponding passageways 279 in the valve units 245. A plurality of passageways 281 in the base portion 273 of the housing member 262 communicate with a tube 283 through a centrally disposed hole 285 in the bottom of the housing member 262 so that suction can be applied from the main vacuum component via the tube 283 to evacuate the chamber 275 when the valve member 266 is in its closed position. An electrical coil 287 is disposed in the bore of the housing member 262 and is energized in response to the switch 236 in the main vacuum component 22 to cause the valve member 266 to move out of sealing engagement with the member 262 against the force of the bias spring 268 into contact with the upper surface of the base portion 273. A plurality of ball check valves 289 are disposed within the passageways 277 to permit the blood serum to flow from the passageways 275 into the passageways 279 of the valve unit 245 and to prevent air from entering the passageways 275 from the passageways 277 when the passageways 275 are evacuated via the tube 283.
Each of the rods 237 of the valve unit 245 includes a transverse passageway or hole 290 which has the same diameter as the passage way 279 or less, whereby when the rods are depressed, the depressed rods 237 have their holes 290 aligned with the passageways 279 to permit the fluid to flow from the valve assembly 24 to the combiner unit 243 via a tube 292.
Considering now the valve units 245 in greater detail, each of the units 245 includes a chamber 294 which has an inlet 296 and an outlet 298 for receiving a chemical reagent to be added to the blood serum for test purposes. A piston device 300 is connected to and forms an integral part of the bottom end of each of the rods 237 for the purpose of forcing the chemical reagent from the chamber 294 through the outlet 298. The piston device 300 includes an upstanding cylindrical piston head 302 which is integrally connected to a circular bottom wall 304 which in turn is biased in an upward direction by the spring 260. The bottom wall 304 is integrally joined to the rod 237 via a pair of diametrically opposed rods 306 and 308 which are slidably mounted in their respective holes in the housing of the valve unit 245. A pair of diametrically opposed bars 311 and 313 are also connected to the periphery of the bottom wall 304 and are positioned so that when the rod 237 is disposed in its normal position, the bars 311 and 313 block and seal the serum passageways 279 in the valve unit 245. A depressed rod therefore causes the piston head 302 to retract almost entirely out of the chamber 274 to permit the chemical reagent to enter the chamber 294 via the inlet 296. When the rods 237 are released by the release mechanism 247, the piston head 302 enters the chamber 294 and forces the liquid contained in the chamber into the outlet 298.
Considering now the combining units 243 in greater detail with reference to FIGS. 13, 17 and 18 of the drawings each of the combining units 243 includes a combining chamber 315 for mixing the blood serum with chemical reagents, a serum measuring device 317 connected in fluid communication with the tube 292 from the valve unit 245 for measuring the amount of blood serum entering the unit 243 and for forcing the blood serum into the combiner chamber 315, and a convoluted tube 319 connected in fluid communication with the readout component 26 for additional agitation of the mixture of blood serum and chemical reagents. The blood serum tube 292 enters a housing 320 of the unit 243 and is connected in fluid communication with the measuring device 317. A ball check valve 322 is disposed in the tube 2892 to prevent any of the blood serum from leaving the unit 243 A tube 324 is connected in fluid communication with the tube 292 between the check valve 232 and the device 317 to transfer the blood serum from the tube 292 to the combining chamber 315. A ball check valve 326 is disposed within the tube 324 to prevent the blood serum from leaving the combining chamber 315 via the tube 324.
The device 317 includes a spring-loaded piston 328 in the tube 292 which is movable toward and away from a vacuum chamber 330. The piston 328 is moved by a predetermined distance in a downward position toward the chamber 330 as a result of the chamber 330 being evacuated by the main vacuum component 22. As the piston rod 328 retracts, a vacuum is created in the tube 292 to draw the blood serum into the tube 292, it being understood that the ball check valve 326 in the tube 324 prevents air from being drawn from the combining chamber 315 into the tube 292. A spring-loaded wedge-shaped plug member 332 is normally spring-biased in a closed position to close and seal a vent opening in the bottom wall of the chamber 330, and in order to release the vacuum in the chamber 330, the plug 332 moves upwardly, whereby the spring-loaded piston 328 returns to its initial position to force the blood serum in the tube 292 into the connecting tube 324 and thus into the combining chamber 315.
As shown in FIG. 18, in order to move the wedge members 332 by a short distance in an upward direction to vent the chambers 330, a plurality of cam members 334 of an electromagnetic release mechanism 336 are disposed opposite the wedge members 332 and are slidably mounted on a baseplate 338. An electromagnet 340, when energized, moves a plurality of shank portions 342 of the cam members 334 toward the magnet 340 against the force of a plurality of bias springs 344 to cause the wedge members 332 to momentarily relieve the vacuum in the chambers 330. The springs 344 cause the slidably mounted cam members 344 to return to their original position.
A tube 346 is connected in fluid communication with the chamber 330 and extends through an opening in the housing 320 of the unit 243 and is connected to the pump component 22 via a distributor 348 which is connected to each of the units 243 and to the valve assembly 239 via the tube 283. The pump component 22 is connected to the distributor 348 via the tube 233.
A tube 350 extends through the component 243 and is connected between a source (not shown) of chemical reagent under pressure and the inlet 296 of the corresponding valve unit 245. A tube 352 connects the outlet 298 of the corresponding valve unit 245 to the combining chamber 315. Should a second reagent be required, a second inlet tube 354 is directly connected to the combining chamber 315. For mixing purposes, a plurality of mixing vanes 356 are disposed within the combining chamber 315 which is supported by a bracket 358 which in turn is connected to the housing 320.
Considering now the readout component 26, a plurality of outlets, such as the outlet 358, of the convoluted tubes 319 are connected in fluid communication with a plurality of chambers, such as the chamber 361, in a plurality of readout units 363, it being understood that there is a readout unit 363 for each combining unit of the combining component 243. An outlet tube 365 is connected in fluid communication with the tube 49 (FIG. 12) to convey the remains of the blood serum to the evacuated waste bottle 51. A transparent curvette 367 is connected in fluid communication between the chamber 361 and the outlet tube 365. A piston assembly 369 is disposed in the chamber 361 and has a semipermeable piston head 370 which is drawn into the curvette 367 by the vacuum in the waste bottle 51 to cause the precipitates of the blood serum-reagent mixture from entering the curvette 367. A spring 372 is connected between the head 370 and a perforated plate 374 to retract the semipermeable head 370 from the curvette 367 to permit the trapped precipitate particles to flow through the curvette 367 to the waste bottle 51 via the tube 365.
A pair of windows 376 and 378 on opposite sides of the curvette 367 are disposed in a passageway 381 in the housing 363 so that a laser beam from the laser component 28 can be directed in the passageway 381 and thus the beam passes through the curvette 367. The windows are composed of nearly nonrefractive quartz material. A beam enters the passageway 381 before it enters the curvette 367 to establish a reference. When the fluid enters the curvette 367, the beam stimulates the specific quantity of material in the curvette 367, since the curvette has a predetermined microvolume. With the material in the curvette 367, the intensity of the secondary radiation of the beam leaving the exit window 378 closely follows Beer's Law, and thus is proportional to the concentration of the blood component being tested, it being understood that different valves of secondary radiation are produced for the various different tests due to the fact that different reagents are added to the blood serum. Moreover, it is to be understood that, if desired, different types of readout components may be used in place of the laser testing technique.
A photomultiplier tube 383 is positioned in the housing 363 in line with the passageway 381 to detect the reference and secondary radiation which passes through the passageway 381 and the curvette 367. The photomultiplier tube 383 in turn converts the radiations into electrical energy to operate a stylus (not shown) for marking a moving graph paper (not shown) in a conventional manner, the conventional graphical recording apparatus not being illustrated in the drawings. A magnet 385 and a light filter 387 are disposed between the curvette 367 and the photomultiplier tube 383, and a lens may be located between the magnet and filter cluster and the photomultiplier tube 383.
When the ON-OFF switch 57 is first closed, the stylus records a normal position on the graph to indicate an area of relatively normal values for a particular blood component. When the material enters the curvette 367, a change is indicated on the graph paper. A switch 391 (FIG. 1) is actuated by the carriage 45 at its initial position to energize a motor 394 (FIG. 19) to move the graph paper, it being understood that there is one stylus for each readout unit 363 and that the graph paper is divided into 10 separate horizontal test quadrants which are each calibrated for its specific test.
Referring now to FIG. 19 of the drawings, a control circuit 396 is located in the control unit 30 and includes a pair of transformers 398 and 401 having their primary windings connected in series with the ON-OFF switch 57 and an indicator lamp 403 on the control panel 59 and which are connectable to a source of AC electrical power by means of a plug 405. A conventional rectifier circuit 407 is connected across a secondary winding 409 of the transformer 398 to rectify the output of the secondary winding 409 for the purpose of driving the motors 111 and 162 which are coupled across the rectifier circuit 407 between the terminals 411 and 413. The terminal 413 is connected to the rectifier circuit 407 by means of the start switch 62A. The motor 111 of the input control device 12 is connected via a wire 415 between the terminal 411 and a resistance switching network generally indicated at 417, which in turn is connected to a safety switch 419. A manually operable reset switch 420 connects the safety switch 419 to the terminal 413 and is operated at the control panel 59. The switch 420 is a single throw, double pole switch, which in its normal position as shown in FIG. 19, connects a lamp 421 across the terminals 411 and 413 to indicate to the attendant that the reset switch 420 must be actuated to its other position before commencing the operation by closing the start switch 62A. In order to return the reset switch 420 to its initial position, a relay 420A is connected to a secondary winding 422 of the transformer 398 via a rectifier circuit 424 and is momentarily actuated by the switch 117 in the input control device 12 to release the spring-loaded switch 420 to cause it to return to its initial position.
The resistance switching network 417 comprises a plurality of switches, such as the switch 426, which are single-throw, double pole switches and which are manually operated by the rods 60 at the control panel 59. Each of the switches connects a resistor, such as a resistor 428, in series with the motor 111 to cause it to run at a proportionately slower speed in proportion to the number of closed switches. In this regard, the switch 426 in its normal position opens the circuit to its resistor 428, but in its closed position, the switch 426 connects the resistor 428 in series with the motor 111. The safety switch 419 is mechanically connected to each of the switches 426 of the network 417 so that when one or more of the switches of the network 417 are closed, the switch 419 is then automatically closed. In this manner, the motor 111 cannot be accidentally energized to cause blood to be withdrawn from a patient since one or more of the switches of the network 417 must first be actuated.
A secondary winding 431 of the transformer 398 is connected to the electromagnet 126 of the clamping device 18 via a rectifier circuit 433 to energize the electromagnet 126 upon closing of the switch 164 which is located slightly beyond the end of the shorter tube 39 of the component 28. A rectifier circuit 435 is connected across a secondary winding 437 of the transformer 398 to supply rectified current via the switch 341 to the electromagnets 254 and 340, which are connected in parallel. In this regard, when the switch 341 is momentarily actuated by the carriage 45 in the component 28, the switch 341 closes momentarily to energize momentarily the electromagnets 254 and 340 whereby the release mechanism 247 releases the rods 237 and the release mechanism 340 causes the vacuum to be relieved in the vacuum chambers 330.
A rectifier circuit 439 is connected across a secondary winding 442 of the transformer 398 to energize the electromagnet 287 of the valve assembly 239. Connected in series with the electromagnet 287 is the switch 236 which is closed when the plunger 214 is fully retracted and which is opened with the plunger 214 returns to its initial position.
The pair of platinum electrodes, which are disposed in the tube 41 of the component 28, and which are shown schematically in FIG. 19 by the box E, are connected across a secondary winding 444 of the transformer 401 via a capacitor 446 which is connected across the winding 444 to supply low voltage and low current excursions to the electrodes for traumatizing the blood for trigger the clotting mechanism of the blood. For the purpose of supplying power to the laser component 28, a secondary winding 448 of the transformer 401 is connected to the laser component 28 via a rectifier circuit 450. A secondary winding 452 of the transformer 401 is connected to the photomultiplier tubes 383 via a rectifier circuit 454 for the purpose of energizing the photomultiplier tubes. In like manner, the graph motor 394 is coupled to a secondary winding 456 of the transformer 401 via a rectifier circuit 458, the graph motor being energized by the switch 391 which is connected in series with the motor 394 and which is energized by the carriage 45 of the unit 18.
Referring now to FIG. 20, there is shown another readout component 460, which is similar to the readout unit 26 of FIG. 17, and which may be used in addition to or in place of the readout units 26. The unit 460 may be used for different types of blood testing procedures, such as where additional reagents are required. The unit 460 includes a housing 462 which supports a cylinder 464 having an inlet 466 adapted to be coupled in fluid communication with the outlet of a combining unit 243. A curvette 468 forms an extension of the cylinder 464 and has an outlet 469 which is connected to a combining chamber 471. A reagent tube 473 is also connected in communication with the chamber 471 to provide a passageway to permit the addition of other reagents. A convoluted tube 475 is connected in fluid communication with a chamber 471 and with a curvette 477 which is disposed in a laser-beam passageway 479. A pair of oppositely disposed windows 481 and 483 permit the laser-beam to pass through the curvette 477. A tube 185 is connected to the curvette 477 and to the vacuum waste bottle 51. A ball check valve 487 and a spring-loaded semipermeable piston 489 are disposed within the cylinder 464 and the curvette 468 in the same manner as the ball check valve 375 and the piston assembly 369 of FIG. 17. A photomultiplier tube 490 is positioned in the housing 462 at the end of the passageway 479 opposite the exit window 483 of the curvette 477 to receive the reference and secondary radiation of the laser-beam and to convert the radiation into electrical energy for operating the stylus of the graphic recording apparatus. A filter 492 is disposed in the passageway 479 between the window 483 and the photomultiplier tube 490.
In view of the foregoing description, it should now be apparent that there is provided in accordance with the present invention a new and improved blood testing machine which is capable of performing a number of different tests simultaneously on a blood sample. Moreover, the blood testing apparatus of the present invention is adapted to automatically draw a blood sample from a patient and divert it into the separate blood testing components of the machine. Blood serum is clotted by electrically energized electrodes, and then the unnecessary solid portion of the blood sample is separated from the blood serum by a dialyzer.
While the present invention has been described in connection with a particular embodiment thereof, it will be understood that many changes and modifications of this invention may be made of those skilled in the art without departing from the true spirit and scope thereof. Accordingly, the appended claims are intended to cover all such changes and modifications as fall within the true spirit and scope of the present invention.