A method and related apparatus for automatic dispensing of a balance bar in a blood preparation process

Abstract

The application discloses a method and related device for automatic discharging of a balancing rod in a blood preparation process, which monitors the continuity of the falling of the balancing rod in real time through a detection unit, maintains the material micro-motion through continuous periodic disturbance when the passage is unobstructed, switches to a single pulse disturbance with higher energy density and limited duration when the duration of the jam exceeds a threshold, and restores normality immediately after breaking the arch bridge. The method takes into account the unblocking effect and material stability. After the pulse ends, the system verifies the falling event, forming a closed-loop control to avoid false unblocking, further coupling the pulse execution with the no-load window timing of the downstream tank wheel to prevent secondary blockage. At the same time, through the first position sensor to confirm the falling, the pushing execution mechanism to transport, the damping limit to prevent overshoot, and the second position sensor to detect arrival and departure, the whole process from discharging to discharging can be monitored and traced.

Description

Technical Field

[0001] This invention relates to the fields of biomedical engineering and automation control technology, and to a method and related apparatus for automatic discharge of balancing rods in the blood preparation process. Background Technology

[0002] In the preparation of blood components, a strict balancing operation is required before whole blood centrifugation to ensure the balance and safe operation of the centrifuge. Currently, balancing primarily relies on manual methods, with operators manually adding filler (such as saline bags) based on the weight of the blood bags. This method is inefficient and struggles to guarantee balancing accuracy and consistency, failing to meet the demands of modern, automated blood preparation systems.

[0003] Although some automatic balancing equipment has emerged in the market, most focus on the weighing and calculation stages, lacking effective technical solutions for the automatic, orderly, and reliable supply and discharge of balancing bars. Furthermore, existing technologies often encounter problems with material jamming and blockage when discharging bar-shaped materials. This is mainly because the bar-shaped materials tend to form an "arching effect" at the hopper outlet due to mutual compression, preventing the material from falling. Traditional solutions include increasing the vibration amplitude or using continuous strong vibration, but this can easily cause the material to jump, rotate, or fly out, affecting the reliability of individual bar separation. Summary of the Invention

[0004] The present invention aims to provide a method and related device for automatic discharge of balancing rods in the blood preparation process, so as to solve the technical problems of easy jamming and difficulty in balancing unblocking and stability when discharging balancing rods in the prior art.

[0005] In a first aspect, embodiments of this application provide a method for automatic discharging of a balancing rod during blood preparation, comprising: A detection unit located at the hopper outlet monitors the continuous descent of the balancing bar in real time and generates a smooth or stuck state signal. When the smooth state signal is active, the drive unit is controlled to operate the screening mechanism with a first drive parameter, causing the screening mechanism to apply continuous periodic disturbances to the balancing bar in the hopper. When the detection unit switches from the smooth state signal to the stuck state signal, and the duration of the stuck state signal exceeds a first preset time threshold, the drive unit is controlled to operate the screening mechanism with a second drive parameter, causing the screening mechanism to apply a single or finite number of non-periodic pulse disturbances to the balancing bar in the hopper. The instantaneous peak energy density of the pulse disturbance is at least three times the average energy density of the continuous periodic disturbance, and the duration of the pulse disturbance is limited to less than a preset pulse width threshold. After the pulse disturbance ends, if the detection unit detects the balancing bar descent event again within the second preset time threshold, the continuous periodic disturbance is restored; otherwise, the pulse disturbance is repeated or an alarm signal is generated.

[0006] Optionally, the detection unit monitors the continuity of the fall by detecting the time interval or the accumulation pressure of the balancing bar, and generating the jamming state signal when the time interval exceeds the jamming determination threshold or the accumulation pressure exceeds the pressure threshold.

[0007] Optionally, the pulse disturbance is an instantaneous overload pulse with an output power of 150% to 500% of the rated power and a duration of 10ms to 200ms.

[0008] Optionally, the method further includes: determining the target weight class according to the balancing instruction, and selecting the corresponding hopper from multiple hoppers storing balancing bars of different weight classes for material supply.

[0009] Optionally, the balancing bars falling from the hopper can be transferred one by one to the downstream guide channel.

[0010] Optionally, the step of applying pulse disturbance by the control drive unit is permitted to be performed only within a time window during which the actuators being transferred one by one are in an idle ready state.

[0011] Optionally, a first position sensor set on the guide channel can be used to detect whether the balancing bar has successfully fallen in. If it is not detected within a preset waiting time, an empty material or jam signal is generated.

[0012] Secondly, embodiments of this application provide an automatic balancing rod dispensing device for blood preparation, including a memory, a processor, and an automatic balancing rod dispensing program stored in the memory and executable on the processor; When the processor executes the automatic discharge program for the balancing rod, it implements the steps of the method for automatic discharge of the balancing rod in the blood preparation process described above.

[0013] Thirdly, embodiments of this application provide a computer-readable storage medium, comprising: The computer-readable storage medium stores an automatic balancing rod discharging program, which, when executed by a processor, implements the steps of the method for automatic balancing rod discharging in the blood preparation process described above.

[0014] Fourthly, embodiments of this application provide an automatic balancing rod dispensing system for blood preparation, comprising: The hopper is used to hold the balancing rods; A screening mechanism is located at the outlet of the hopper and is used to apply mechanical disturbance to the balancing bar; The detection unit is located at the outlet of the hopper and is used to monitor the continuous falling of the balancing bar and generate a smooth state signal or a stuck state signal. The drive unit is connected to the screening mechanism via a transmission. A control unit, electrically connected to the detection unit and the drive unit, is configured to perform the steps of the method described above for the automatic discharging of a balancing rod during blood preparation.

[0015] As can be seen from the above technical solutions, the embodiments of this application have the following advantages: This application uses a detection unit to monitor the continuous descent of the balancing rod in real time. When the flow is smooth, continuous periodic disturbances maintain the material's micro-movement. When the jamming duration exceeds a threshold, it switches to a single-pulse disturbance with higher energy density and limited duration, breaking the bridging and immediately restoring normal operation. This balances both unblocking effect and material stability. After the pulse ends, the system verifies the descent event, forming a closed-loop control to avoid false unblocking. Furthermore, the pulse execution is time-coupled with the downstream wheel's idle window to prevent secondary blockage. Simultaneously, a first position sensor confirms material drop, the push actuator delivers the material, damping limits prevent overshoot, and a second position sensor detects arrival and departure, enabling full monitoring and traceability of the entire process from material release to discharge. In summary, this application effectively solves the problems of easy jamming, difficulty in balancing unblocking and stability, and unknowable discharge status in existing technologies. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic flowchart of the automatic discharge method for balancing bars according to the present invention; Figure 2 This is a schematic diagram of the balancing rod pushing and discharging process in this application. Detailed Implementation

[0018] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0019] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0020] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0021] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0022] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0024] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0025] The method described in this application can be applied to servers, devices, terminals, or other devices with logical processing capabilities; therefore, this application does not limit its application. For ease of description, the following description uses a terminal as the executing entity.

[0026] Please see Figure 1 and Figure 2 This embodiment provides a method for automatic discharging of a balancing rod during blood preparation. This method can be applied to automatic balancing equipment in a blood preparation system. (Refer to...) Figure 1 The method includes the following steps: 101: The continuous falling of the balancing bar is monitored in real time by a detection unit set at the outlet of the hopper, and a smooth status signal or a stuck status signal is generated.

[0027] Specifically, the continuous descent of the balancing bar is monitored in real time by a detection unit located at the hopper outlet. The detection unit can employ a through-beam photoelectric sensor, or at least one of a piezoelectric thin-film sensor, a capacitive proximity sensor, or a motor current detection module. The detection principle is to detect the time interval or accumulation pressure of the balancing bar. When the balancing bar falls normally, the sensor generates a periodic blocking signal; when jamming occurs, the signal remains unchanged for an extended period or the accumulation pressure increases.

[0028] The detection unit generates two status signals based on the monitoring results: a smooth status signal, which indicates that the balancing bar is falling continuously or intermittently, and a stuck status signal, which indicates that the bar has not fallen for more than a preset time or that the pressure exceeds the limit. Specifically, if the time interval of the balancing bar exceeds the preset stuck judgment time threshold, such as 300ms, or if the accumulated pressure exceeds the preset pressure threshold, a stuck status signal is generated.

[0029] 102: When the smooth state signal is in effect, the control drive unit drives the screening mechanism to operate with the first drive parameter, so that the screening mechanism applies continuous periodic disturbance to the balancing bar in the hopper.

[0030] When the system is in a smooth operation state, the control drive unit drives the screening mechanism with the first drive parameter. The screening mechanism is, for example, a swing block, with one end a fixed rotating shaft and the other end connected to a motor via an eccentric crankshaft. The first drive parameter corresponds to a relatively small motor speed and torque, causing the screening mechanism to apply continuous periodic disturbances to the balancing rods in the hopper. This disturbance manifests as small-amplitude, low-frequency reciprocating oscillations, aimed at maintaining the material in a micro-motion state and preventing the accumulation of static friction, but not enough to cause the material to jump or fly out.

[0031] 103: When the detection unit switches from the unobstructed state signal to the stuck state signal, and the duration of the stuck state signal exceeds the first preset time threshold, the drive unit is controlled to drive the screening mechanism to run with the second drive parameter, so that the screening mechanism applies a single or limited number of non-periodic pulse disturbances to the balancing bar in the hopper.

[0032] Specifically, when the detection unit switches from a smooth state signal to a stuck state signal, and the duration of the stuck state signal exceeds a first preset time threshold, the system determines that an arch bridge has become stuck. At this time, the control drive unit switches to the second drive parameter, causing the screening mechanism to apply a single or a limited number of non-periodic pulse disturbances. In this embodiment, the first preset time threshold can be 100ms, used to filter out transient interference.

[0033] Among them, the instantaneous peak energy density of non-periodic pulse disturbance is at least three times that of the average energy density of continuous periodic disturbance.

[0034] In one specific embodiment, by increasing the instantaneous power of the motor to 300% of the rated power for 50ms, the screen moving block is made to swing rapidly at a large angle, with an amplitude of 12-15mm and an angular velocity of 300° / s, generating an impact force sufficient to break the jamming of the arch bridge.

[0035] The duration of the pulse disturbance is limited to less than a preset pulse width threshold, which can be 10-200ms, to avoid prolonged strong disturbances that could cause material to fly out.

[0036] The number of pulse disturbances can be single or finite, such as 1-3 times, rather than continuous periodicity.

[0037] In a preferred embodiment, the pulse disturbance is an instantaneous overload pulse with an output power of 150% to 500% of the rated power and a duration of 10ms to 200ms.

[0038] 104: After the pulse disturbance ends, if the detection unit detects the balancing rod falling event again within the second preset time threshold, the continuous periodic disturbance is restored; otherwise, the pulse disturbance is applied again or an alarm signal is generated.

[0039] After the pulse disturbance ends, the system enters the verification phase. The detection unit continuously monitors the continuity of the falling bars. If at least one falling event of the balancing bar is detected again within the second preset time threshold, it indicates that the arch bridge has been successfully destroyed. The system control drive unit restores the first drive parameters and re-enters the continuous periodic disturbance mode in step 102.

[0040] If no falling event is detected within the second preset time threshold, it indicates that the pulse has failed to clear the blockage. The system has two options: repeat the pulse disturbance, with the maximum number of repetitions set to 3, or directly generate an alarm signal and stop the automatic discharge operation, waiting for manual intervention.

[0041] In step 101, the detection unit can be implemented in various ways, including but not limited to: Through-beam sensor: Installed on both sides of the hopper outlet channel, with the transmitter and receiver facing each other. When the balancing bar passes by, it blocks the light path, generating a pulse signal. By calculating the time interval between adjacent pulses, it determines whether there is a jam.

[0042] Piezoelectric thin film sensor: Attached to the channel wall, a voltage signal is generated by the slight impact of the balancing rod falling, and the detection frequency is measured.

[0043] Capacitive proximity sensor: detects changes in the dielectric constant of materials within the channel to determine bulk density.

[0044] Motor current detection module: When jamming occurs, the motor load increases and the current rises. The jamming is determined by detecting abnormal current.

[0045] In one embodiment, the downstream transfer mechanism can be a Geneva wheel, and the method further includes acquiring the rotational phase signal of the downstream transfer mechanism. The step of the control drive unit operating with the second drive parameters is only permitted to be executed within a time window when the transfer mechanism is in an idle, ready state. If a jamming signal appears outside this time window, the pulse disturbance is delayed until the next time window. This avoids forcibly dropping material before the Geneva wheel is in place, which could cause the balancing bar to fall into the wrong position or cause secondary blockage.

[0046] After completing the above feeding steps, the method for automatic feeding of the balancing rod in the blood preparation process also includes a downstream feeding process: 105: Transfer the balancing bars falling from the hopper one by one to the downstream guide channel.

[0047] In one specific embodiment, the transfer of each balancing bar is achieved by a grooved wheel: the grooved wheel is provided with a slot to accommodate a single balancing bar. The grooved wheel rotates 180 degrees, causing the slot to rotate from the receiving position to the dropping position, and the balancing bar falls into the V-shaped guide channel under the action of gravity.

[0048] 106: The first position sensor installed on the guide channel detects whether the balancing bar has successfully fallen in. If it is not detected within the preset waiting time, an empty material or jam signal is generated.

[0049] 107: In response to a confirmation signal that the balancing bar has fallen into the guide channel, the control push actuator conveys the balancing bar along the guide channel to the discharge position. During the conveying process, a damping force is applied to the balancing bar at the discharge position to prevent it from rushing out of the discharge position due to inertia.

[0050] 108: The arrival and departure status of the balancing rod is monitored by a second position sensor set at the discharge position. When the arrival of the balancing rod is detected and it is removed, the signal changes from blocked to open, generating a discharge success signal; if the arrival is not detected within a preset time, or if the rod is not removed after arriving and the preset dwell time is exceeded, a discharge abnormality signal is generated.

[0051] In one embodiment, the method for automatically discharging balancing rods during blood preparation further includes: in response to a balancing command, determining the target weight class of the required balancing rods; and selecting a corresponding hopper from a plurality of hoppers storing balancing rods of different weight classes for feeding. Each hopper or bin is used to store balancing rods of a single weight class, such as 10g, 20g, or 50g, and the system automatically switches the feeding hopper according to the calculated balancing requirements.

[0052] In a specific application scenario: The system performs a self-check, confirming that each hopper is filled with the corresponding weight class of balancing bars and that the sensors are calibrated normally. The control unit then activates the screening mechanism of all hoppers with the first drive parameters (continuous periodic disturbance, amplitude 2mm, frequency 1.5Hz).

[0053] Receive balancing command: The host computer sends a command requesting the discharge of a 50g balancing rod. The control unit selects the 50g hopper and opens its outlet baffle.

[0054] The balancing bar falls normally under continuous periodic disturbances, and the groove wheel catches one bar every 180° rotation, falling into the V-shaped channel.

[0055] In one instance, the arch bridge became stuck. The detection unit did not detect a falling signal within 300ms, thus generating a stuck status signal.

[0056] If the jamming lasts for 120ms (exceeding the first preset time threshold of 100ms), the control unit triggers a pulse disturbance: the motor is momentarily overloaded to 2.5A for 40ms, the swing block violently impacts the rod pile, and the arch bridge breaks.

[0057] Within 150ms after the pulse ended, two drop events were detected, and the system resumed continuous periodic disturbances.

[0058] The first position sensor detects that the balancing bar has fallen into the V-shaped channel and starts the pusher motor.

[0059] The pusher pushes the balancing bar to the discharge position at 50mm / s, and the damping roller prevents overshoot.

[0060] The second position sensor detects the arrival of the balancing rod, meaning the sensor's light path is blocked.

[0061] The external robotic arm removes the balancing bar, the optical path of the second position sensor is restored, and a discharge success signal is generated.

[0062] The system recorded success and is waiting for the next instruction.

[0063] If the blockage cannot be cleared after three consecutive pulses, the system will issue an audible and visual alarm, and the operator will manually handle the situation by opening the hopper through the transparent door.

[0064] This invention provides an automatic balancing rod dispensing device for blood preparation, including a memory, a processor, and an automatic balancing rod dispensing program stored in the memory and executable on the processor; When the processor executes the automatic discharge program for the balancing rod, it implements the steps of the method for automatic discharge of the balancing rod in the blood preparation process described above.

[0065] Embodiments of this application provide a computer-readable storage medium, comprising: The computer-readable storage medium stores an automatic balancing rod discharging program, which, when executed by a processor, implements the steps of the method for automatic balancing rod discharging in the blood preparation process described above.

[0066] Embodiments of this application provide an automatic balancing rod dispensing system for blood preparation, comprising: The hopper is used to hold the balancing rods; A screening mechanism is located at the outlet of the hopper and is used to apply mechanical disturbance to the balancing bar; The detection unit is located at the outlet of the hopper and is used to monitor the continuous falling of the balancing bar and generate a smooth state signal or a stuck state signal. The drive unit is connected to the screening mechanism via a transmission. The control unit, electrically connected to the detection unit and the drive unit, is configured to perform the steps of the method described above for the automatic dispensing of a balancing rod during blood preparation. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0067] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0068] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0069] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0070] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

Claims

1. A method for automatic discharge of a balancing rod during blood preparation, characterized in that, include: The continuous falling of the balancing bar is monitored in real time by a detection unit set at the outlet of the hopper, and a smooth status signal or a stuck status signal is generated. When the unobstructed state signal is in effect, the control drive unit drives the screening mechanism to operate with the first drive parameter, so that the screening mechanism applies continuous periodic disturbance to the balancing bar in the hopper. When the detection unit switches from the unobstructed state signal to the stuck state signal, and the duration of the stuck state signal exceeds the first preset time threshold, the drive unit is controlled to drive the screening mechanism to run with the second drive parameter, so that the screening mechanism applies a single or limited number of non-periodic pulse disturbances to the balancing bar in the hopper. Wherein, the instantaneous peak energy density of the pulse disturbance is at least three times the average energy density of the continuous periodic disturbance, and the duration of the pulse disturbance is limited to less than a preset pulse width threshold. After the pulse disturbance ends, if the detection unit detects the balancing rod falling event again within the second preset time threshold, the continuous periodic disturbance is restored; otherwise, the pulse disturbance is applied again or an alarm signal is generated.

2. The method for automatic discharge of the balancing rod in the blood preparation process according to claim 1, characterized in that, The detection unit monitors the continuity of the fall by detecting the time interval or the accumulation pressure of the balancing bar. When the time interval exceeds the jamming judgment threshold or the accumulation pressure exceeds the pressure threshold, the jamming state signal is generated.

3. The method for automatic discharge of the balancing rod in the blood preparation process according to claim 1, characterized in that, The pulse disturbance is an instantaneous overload pulse with an output power of 150% to 500% of the rated power and a duration of 10ms to 200ms.

4. The method for automatic discharge of the balancing rod in the blood preparation process according to claim 1, characterized in that, The method further includes: determining the target weight class according to the balancing instruction, and selecting the corresponding silo from multiple silos storing balancing bars of different weight classes for material supply.

5. The method for automatic discharge of a balancing rod in blood preparation according to claim 1, characterized in that, Also includes: The balancing bars falling from the hopper are transferred one by one to the downstream guide channel.

6. The method for automatic discharge of a balancing rod in blood preparation according to claim 5, characterized in that, The step of applying pulse disturbance by the control drive unit is permitted to be performed only within the time window during which the actuators being transferred one by one are in an idle and ready state.

7. The method for automatic discharge of a balancing rod in blood preparation according to claim 1, characterized in that, Also includes: The first position sensor installed on the guide channel detects whether the balancing bar has successfully fallen in. If it is not detected within the preset waiting time, an empty material or jam signal is generated.

8. An automatic discharge device for balancing rods in blood preparation process, characterized in that, include: Memory, processor, and automatic discharge program for balancing bars stored in the memory and executable on the processor; When the automatic discharge program for the balancing rod is executed by the processor, it implements the steps of the method for automatic discharge of the balancing rod in the blood preparation process as described in any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores an automatic balancing rod discharging program, which, when executed by a processor, implements the steps of the method for automatic balancing rod discharging in the blood preparation process as described in any one of claims 1 to 7.

10. An automatic feeding system for balancing rods in blood preparation, characterized in that, include: The hopper is used to hold the balancing rods; A screening mechanism is located at the outlet of the hopper and is used to apply mechanical disturbance to the balancing bar; The detection unit is located at the outlet of the hopper and is used to monitor the continuous falling of the balancing bar and generate a smooth state signal or a stuck state signal. The drive unit is connected to the screening mechanism via a transmission. A control unit, electrically connected to the detection unit and the drive unit, is configured to perform the steps of the method for automatic discharge of a balancing rod during blood preparation as described in any one of claims 1 to 7.

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