BACKGROUND OF THE INVENTION

In a low cost clinical analyzer, time can be traded for complexity and multiple mechanisms. In other words, with a longer cycle time a complete sample delivery cycle can be achieved followed by a complete reagent delivery cycle without overlap in time. The acceptance of a longer cycle time in the low cost analyzer allows for the possibility of a single pipettor assembly thus combining the sample and reagent probe functionalities. In such a situation, two probe mechanisms can still be driven with a single X-Y-Z drive.

What is needed, therefore, is a simple mechanism for moving and driving sample and reagent delivery devices.

BRIEF SUMMARY OF THE INVENTION

In one embodiment, a drive mechanism mounted on an XY gantry of a clinical analyzer comprises first and second passive wheels disposed on the XY gantry and a movable drive carriage disposed adjacent the first and second passive wheels. A drive wheel is disposed on the movable drive carriage as are first and second brake structures that are spaced apart from one another with the drive wheel disposed in-between. The drive carriage is arranged such that the drive wheel is disposed between the first and second passive wheels and the first passive wheel is between the first brake structure and the drive wheel and the second passive wheel is between the drive wheel and the second brake structure.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Embodiments of the present invention may be better understood by referring to the following description in conjunction with the accompanying drawings in which:

Fig. 1 is a perspective view of one embodiment of the present invention;

Figs. 2A-2C are top views of the embodiment of Fig. 1 in different modes of operation;

Figs. 3A-3C are sides views of the embodiment of Fig. 1 in different modes of operation corresponding, respectively, to Figs. 2A-2C;

Fig. 4 is a schematic view of one embodiment of the present invention;

Fig. 5 is a perspective view of the embodiment of Fig. 4;

Fig. 6 is a schematic view of one embodiment of the present invention; Fig. 7 is a perspective view of the embodiment of Fig. 6;

Fig. 8 is a perspective view of an embodiment of the present invention;

Fig. 9 is a view of one embodiment of the present invention;

Fig. 10 is a side view of the embodiment of Fig. 9; and

Fig. 11 is a perspective view of an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present invention. It will be understood by those of ordinary skill in the art that these embodiments of the present invention may be practiced without some of these specific details. In other instances, well-known methods, procedures, components and structures may not have been described in detail so as not to obscure the embodiments of the present invention.

One embodiment of the present invention is a single X-Y gantry on which two probe Z-axis mechanisms are mounted, one for sample delivery and one for reagent delivery. Only one of the Z- axis mechanisms, however, is driven at any point in time. Thus, a simpler drive mechanism is provided where a drive motor on a horizontal slide engages, when directed, with either one of the two Z-axis mechanisms which then moves an attached probe up or down. When one Z-axis mechanism is being driven, a brake holds the other Z-axis mechanism in position and prevents it from moving due to either its natural weight and/or vibrations in the system.

A single drive assembly 100, as shown in Fig. 1, includes a slotted carriage 104 on which a drive wheel 108, mounted on a drive wheel spindle 110, is provided. In one embodiment of the present invention, a drive motor 112 is connected to the drive wheel spindle 110 in order to rotate the drive wheel 108. The drive motor 112 may be a stepper motor or other similar type motor. Further, in an alternate embodiment, the stepper motor may be integral with the drive wheel 108. In any event, the drive motor 112 receives instruction from a controller, not shown, as to which direction the drive wheel 108 should spin, how fast, how long, etc.

Left and right longitudinal carriage slots 114-L, 114-R are provided in the slotted carriage 104. Left and right brake structures 116-L, 116-R are provided on the slotted carriage 104 adjacent a respective left and right carriage slot 114-L, 114-R. It should be noted that the reference to left and right, as found throughout the specification, is merely for convenience in identifying various components. The recitation of left and right, however, is not meant to be limiting in any way.

Left and right passive wheels 120-L, 120-R are mounted, respectively, on left and right passive wheel spindles 124-L, 124-R positioned through the left and right carriage slots 114-L, 114-R. The left and right passive wheel spindles 124-L, 124-R are mounted on a surface, not shown, such that a distance between the left and right passive wheel spindles 124-L, 124-R remains the same. The slotted carriage 104, however, is able to move independently, i.e., separately, along the direction defined by the left and right carriage slots 114-L, 114-R.

In operation, the slotted carriage 104 is moved in order to allow the drive wheel 108 to come into contact with either the left passive wheel 120-L or the right passive wheel 120-R. Advantageously, when the drive wheel 108 is coupled to one of the left or right passive wheels 120- L, 120-R, the other passive wheel is kept motionless by operation of the corresponding left or right brake 116-L, 116-R.

Referring to Fig. 2A, in a neutral or maintenance position, the drive wheel 108 is not in contact with either of the left or right passive wheels 120-L, 120-R and the left and right brakes 116-L, 116-R are not in contact with either the left or right passive wheels 120-L, 120-R. Accordingly, the drive wheel 108 is free to spin as are the left and right passive wheels 120-L, 120-R.

In order to drive, for example, the left passive wheel 120-L, the slotted carriage 104 is moved to the left, as shown in Fig. 2B. By moving the slotted carriage 104 to the left, the drive wheel 108 contacts the left passive wheel 120-L and the right brake 116-R contacts the right passive wheel 120-R and prevents the right passive wheel 120-R from moving.

Similarly, in order to drive the right passive wheel 120-R with the drive wheel 108, the slotted carriage is moved to the right and the left brake 116-L then contacts the left passive wheel 120-L and prevents it from rotating while the right passive wheel 120-r is driven by the drive wheel 108.

Whereas the view shown in Figs. 2A-2C is a top view of the single drive assembly 100 shown in Fig. 1, Figs. 3A-3C are side views of the single drive assembly 100 as shown with respect to Figs. 2A-2C. Thus, the slotted carriage moves from the neutral position, Fig. 3A, to either of the drive positions, Figs. 3B and 3C, in order to drive one of the left or right passive wheels 120-L, 120-R while the other is held in place. It should be noted that the spindles 124-L, 124-R do not move with respect to one another.

As shown in Figs. 3A - 3C, the drive wheel 108 and the left and right passive wheels 120-L, 120-R are in a same plane to facilitate transfer of driving force from the drive wheel 108. Of course, the drive wheel 108 and the passive wheels may be of different thickness in order to account for any tolerances or to make better contact. In any event, a sufficient portion of the surfaces of the wheels are intended to make contact. In an implementation where the single drive assembly 100 is used to move two tools, for example, a sample probe and a reagent probe in a Z direction, an embodiment of the present invention would include a Z movement assembly 400 as shown in Fig. 4. In one embodiment, the Z movement assembly 400 would be mounted on an XY gantry 402 disposed over a plurality of locations, e.g., cuvettes, in a clinical analyzer. The operation of an XY gantry is well known to those of ordinary skill in the art. Accordingly, the Z movement assembly 400 includes the slotted carriage 104 with the drive wheel 108, the left and right passive wheels 120-L, 120-R and the left and right brakes 116-L, 116-R. The left and right carriage slots 114-L, 114-R would also be included, however, they are not shown here for purposes of clarity.

In addition to the foregoing, left and right drive hubs 404-L, 404-R are provided, respectively, on the left and right passive wheels 120-L, 120-R. Left and right drive belts 408-L, 408-R are coupled to the left and right drive hubs 404-L, 404-R, respectively, and run around respective left and right return hubs 412-L, 412-R. As a non-limiting example, a sample probe 414 is coupled to the left drive belt 408-L and a reagent probe 418 is coupled to the right drive belt 408- R.

It should be noted that the provision of the left and right drive hubs 404-L, 404-R on the left and right passive wheels 120-L, 120-R is for purposes of example only and not meant to be limiting. The hubs, or a similar structure, could be coupled to the left and right passive wheels 120- L, 120-R but located on the other side of the carriage 104. Further, the belts could be coupled to the spindles or similar elongate structures as would be understood by one of ordinary skill in the art.

In operation, the drive wheel 108 is coupled to either one or the other of the left or right passive wheels 120-L, 120-R in order to raise or lower the sample probe 414 or the reagent probe 418. By operation of the movement of the slotted carriage 104 when one or the other of the sample probe 414 and the reagent probe 418 is being moved, the other is being held in place due to the left or right brake 116-L, 116-R pressing against the other of the left or right passive wheel 120-L, 120-R.

The sample probe 414 and the reagent probe 418 are coupled by appropriate tubing to respective reservoirs, as shown in Fig. 5, as are provided in many clinical analyzer systems as known to those of skill in the art.

In another embodiment of the present invention, a variation of the single drive assembly 100 is used to drive two different pumping systems. Referring now to Fig. 6, a single drive pumping system 500 includes the slotted carriage 104 with the drive wheel 108, the left and right passive wheels 120-L, 120-R and the left and right brakes 116-L, 116-R. Left and right screw drives 504-L, 504-R are coupled to the left and right passive wheels 120-L, 120-R, respectively. In other words, rather than left and right passive wheel spindles 124-L, 124-R, the single drive assembly 500 operates the left and right screw drives 504-1, 504-R. Left and right screw couplers 508-L, 508-R are, respectively, coupled to the left and right screw drives 504-L, 504-R. Left and right screw drive shafts 512-L, 512-R are coupled to the left and right screw couplers 508-L, 508-R, respectively. A plunger 514 is coupled to a distal end of each of the left and right screw drive shafts 512-L, 512-R. The plunger 514 on the end of the left screw drive shaft 512-L moves within an air pump 516 that, in one embodiment of an immunoassay analyzer, is coupled to the sample probe using disposable tips 414 shown in Figs. 4 and 5. The plunger 514 on the end of the right screw drive shaft 512-R is provided within a water pump 520. The water pump 520 is coupled to a three-way valve 524. The three-way valve 524 has one port coupled to the fixed washable reagent probe 418 of the embodiment shown in Figs. 4 and 5 while another port of the three-way valve 524 is coupled to a pressurized water source, not shown.

In operation, when the slotted carriage 104 is moved such that the drive wheel 108 engages the left passive wheel 120-L, the left screw drive shaft 512-L is caused to move within the air pump 516 to move the air or fluid to, or from, the sample probe 414. While the left passive wheel 120-L is being driven, the right passive wheel 120-R is held in place by the right brake 116-R and therefore, the plunger 514 within the water pump 520 remains stationary. Of course, when the drive wheel 108 is in contact with the right passive wheel 120-R, the plunger 514 on the end of the right screw drive shaft 512-R within the water pump 520 is being operated while the plunger 514 within the air pump 516 remains stationary.

As a result, a single drive source is provided for moving two separate mechanisms where it is not necessary that the mechanisms be driven and/or moved at the same time.

Fig. 7 is a schematic view of a portion of the single drive pumping system 500 as shown in

Fig. 6.

Referring now to Fig. 8, an alternate embodiment of the present invention includes a single drive assembly 800 that includes a slotless carriage 804 and a slotted frame 808. Here, left, middle and right frame slots 812-L, 812-M, 812-R are provided in the slotted frame 808. The left and right passive wheels 120-L, 120-R, are mounted, respectively, on left and right passive wheel spindles 124-L, 124-R disposed on the slotted frame 808. The left brake 116-L is mounted on a corresponding left brake mount 816-L that is provided through the left frame slot 812-L. Similarly, the right brake 116-R is mounted on a right brake mount 816-R that is provided through the right frame slot 812-R and onto the slotless carriage 804. The drive wheel 108 is mounted on its drive wheel spindle 110 which is provided through the middle frame slot 812-M and coupled to the motor 112 attached to the slotless carriage 804. Of course, one of ordinary skill in the art would understand that the drive wheel may have an integrated motor or the motor 112 could be mounted on an upper surface of the slotless carriage 804.

The drive assembly 800 operates similarly to the embodiments described above in that the slotless carriage 804 is moved in order to position the drive wheel 108 against one of the left or right passive wheels 120-L, 120-R while the other is held still by the corresponding left or right brake 116-L, 116-R. One of ordinary skill in the art would understand how the assembly 800 would be disposed in order to operate either the belt or screw driven embodiments described above.

In addition, the slotted carriage 104, the slotless carriage 804 and the slotted frame 808, in their respective embodiments, may be moved between the three positions, i.e., neutral, left driving and right driving, using a solenoid, a motor, a pneumatic device, etc. The left and right brakes 116- L, 116-R may be made of a material sufficient to stop movement of the left and right passive wheels 120-L, 120-R and may comprise a hard material such as a plastic and, where the left and right passive wheels 120-L, 120-R are implemented as gears, may include matching teeth or impressions to couple with the gear teeth and may be spring loaded to provide a braking force against the left and right passive wheels 120-L, 120-R.

Still further, one of ordinary skill in the art will understand that movement of the drive wheel 108, the slotted carriage 104, the slotless carriage 804 and the slotted frame 808 may be controlled by a central controller as known in the art. Further, the setting of the three-way valve 524 would also be controlled by this central controller although operation of the central controller is not a part of the embodiments of the present invention.

Referring now to Figs. 9 and 10, another embodiment of the present invention includes a single drive assembly 900 that includes a drive carriage 904 with left and right brakes 116-L, 116-R extending from a surface of the drive carriage 904. The drive wheel 108 is mounted on its drive wheel spindle 110 which is provided through the drive carriage 904 and coupled to the motor 112. Of course, one of ordinary skill in the art would understand that the drive wheel may have an integrated motor or the motor 112 could be mounted on an upper surface of the drive carriage 904.

The left and right passive wheels 120-L, 120-R, are mounted, respectively, on left and right passive wheel spindles 124-L, 124-R that are fixedly mounted on a surface, not shown, where the distance between the passive wheels 120-L, 120-R is fixed.

The drive assembly 900 operates similarly to the embodiments described above in that the drive carriage 904 is arranged such that the drive wheel 108 is positioned between the passive wheels 120-L, 120-R. This is shown in Fig. 10, a view of the embodiment shown in Fig. 9 from the direction A, where the system is in the neutral position. The drive carriage 904 is then moved, as described above, in order to position the drive wheel 108 against one of the left or right passive wheels 120-L, 120-R while the other is held still by the corresponding left or right brake 116-L, 116-R. One of ordinary skill in the art would understand how the assembly 900 would be disposed or configured in order to operate either the belt or screw driven embodiments described above, i.e., how the belt and/or screw components would be coupled to the passive wheels 120-L, 120-R.

In another embodiment of the present invention, a drive carriage is configured with multiple drive wheels. Referring now to Fig. 11, a double-drive carriage 950 is provided with two drive wheels 108a, 108b positioned between, respectively, pairs of left and right passive wheels (120-L1, 120-R1) and (120-L2, 120-R2). The double-drive carriage 950 also includes left and right brakes 116-L, 116-R. While each of the left and right brakes 116-L, 116-R is shown as a single structure, in an alternate embodiment, there may be two pairs of brake structures with one pair for each set of passive wheels.

Drive mechanisms 954-R1, 954-R2, 954-L1 and 954-L2 are coupled to the passive wheels, 120-R1, 120-R2, 120-L1 and 120-L2, respectively. The drive mechanisms may be the belt or screw driven structures described above.

Similar to the embodiments described above, the double-drive carriage 950 is moved left or right to engage one set of drive wheels while holding the other set in position with the opposite brake. The drive wheels 108a, 108b may be driven with separate motors and controllers although there may be an implementation where the drive wheels are driven from the same motor and controlled together. Variations on the controlling of the drive wheels will be apparent to those of ordinary skill in the art.

Advantageously, in one implementation, the double-drive carriage embodiment can be provided in an XY gantry and used to maneuver a sample probe and a reagent probe. Thus, for example, the left passive wheel 120-L1 may drive a sample probe while the other left passive wheel 120-L2 drives a reagent probe. As the drive wheels 108a, 108b are separately controlled, the motion of the sample and reagent probes can be separately controlled when positioned over an assay location.

The double-drive carriage 950 is similar to the slotted carriage 104 as shown in Fig. 1, however, this is only for ease of explanation. One of ordinary skill in the art will understand that either the slotless drive carriage 804, shown in Fig. 8, or the drive carriage 904, shown in Fig. 9, could be adapted to have multiple drive wheels and multiple pairs of passive wheels. It should be noted that while the drive wheel 108 and the left and right passive wheels 120-L, 120-R have been described as wheels where the driving force is friction-based, an alternate embodiment of the present invention includes gears where each of the drive wheels 108 and the left and right passive wheels 120-L, 120-R are configured as gears with teeth that intermesh in order to provide movement to either the belt, the screw drive or other mechanism.

Further, one of ordinary skill in the art will understand that application of the embodiments of the present invention are not limited to just driving belts or screws and that other movement mechanisms are envisioned as being within this disclosure, for example, belts, pulleys, lead screw, rack and gear, rack and pinion, etc.

Having thus described several features of at least one embodiment of the present invention, it is to be appreciated that various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure and are intended to be within the scope of the invention. Accordingly, the foregoing description and drawings are by way of example only, and the scope of the invention should be determined from proper construction of the appended claims, and their equivalents.