DETAILED ACTION
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 04 November 2025 has been entered.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1, 2 and 4-8 are rejected under 35 U.S.C. 103 as being unpatentable over Alstad (US 20100301071) in view of Nelson (US 20130189120), Haegermarck (US 20210244255) and Zhou (US 20150158907).
With respect to claim 1, Alstad discloses a method of controlling fluid flow comprising providing fluid to a first conduit (Figure 1:30) of a pump assembly (Figure 1:20), wherein the pump assembly further includes a lever arm (Figure 1:28) and a rotor (Figure 1:24) operatively coupled to a pump motor (Figure 4:32). The rotor includes one or more rollers (Figure 6:48) configured to rotate and compress the first fluid conduit in order to pump fluid through the first fluid conduit. This is taught in paragraphs [0023]-[0028]. Alstad, however, does not expressly state that torque and rotor position are measured to estimate a fluid flow rate value through the first conduit and thereby modify the rotation of the rotor based on the estimated fluid flow rate value.
Nelson discloses a method of controlling fluid flow comprising providing a fluid to a first fluid conduit (Figure 1:12) of a pump assembly, wherein the pump assembly includes a rotor (Figure 1:11), a pump motor (Figure 1:32), and a plurality of rollers (Figure 1:16). Nelson teaches in paragraphs [0028]-[0030] that a rotor position value is measured by a sensor (Figure 1:28), and that this rotor position value is used to modify the rotation of the rotor to affect fluid flow through the first fluid conduit.
Haegermarck discloses a method of controlling fluid flow comprising providing a fluid to a first fluid conduit (Figure 1:17) in communication with a pump assembly (Figure 1:11). Paragraph [0037] states that flow rate through the conduit is estimated by monitoring the torque of the pump (“ The flow rate of liquid flowing through the drain conduit 17 significantly affects the torque of the drain pump and the electrical quantities of the electric motor of the drain pump 11. For example, if the flow rate of liquid flowing through the drain conduit 17 is high, the torque of the drain pump 11 is high. Contrarywise, if the flow rate of liquid flowing through the drain conduit 17 is low, and/or if the drain pump 11 is sucking air, the torque of the drain pump 11 is low”).
Before the effective filing date of the claimed invention, it would have been obvious to measure torque value and rotor position values and subsequently use this information to estimate flow rate and modify the rotation of the Alstad rotor. Nelson shows how rotor position information measured in real time may be used to determine when the rotation of the rotor needs to be sped up in order to recovery from a slowdown caused by a flow anomaly. Haegermarck teaches that torque sensors are typically used to detect an increased or decreased load on the pump, which is indicative of the flow rate of liquid flowing through the conduit. Haegermarck states that this allows one to estimate flow rate “in a simple and efficient manner without the need for additional sensors”.
Alstad still differs from the claimed invention because Alstad does not expressly state that the rotor rotates at a rate between 1 rpm and 20 rpm.
Zhou discloses a method of controlling fluid flow comprising providing a fluid to a first fluid conduit (Figure 1:6) of a pump assembly (Figure 1:8), wherein the pump assembly may be configured as a peristaltic pump. Zhou states in paragraph [0131] that the rotor may be rotated at a variety of rpm, including “between about 10 RPM and about 20 RPM”.
Before the effective filing date of the claimed invention, it would have been obvious to adjust the Alstad rpm in order to modify flow rate. Those of ordinary skill would have understood that lower rpm of the rotor in a peristaltic pump would produce lower flow rates. Accordingly, it would have been obvious to reduce the Alstad rpm to between 1 and 20 when it is not necessary to maintain a high flow rate. By citing a wide variety of pump rpm and flow rate values, Zhou is evidence that it is well within the ability of one of ordinary skill to experiment with pump rotation rate in order to optimize system performance.
With respect to claim 2, Alstad, Nelson, Haegermarck and Zhou disclose the combination as described above. Wells further describes measuring motor current value and a pressure value in paragraphs [0029]-[0034] and [0048].
With respect to claim 4, Alstad, Nelson, Haegermarck and Zhou disclose the combination as described above. Alstad, Nelson and Haegermarck further show how it is known to estimate a flow rate from rotor activity through known relationships. Those of ordinary skill would have found it useful to use known sensors to obtain information used to calculate flow rate when the Alstad peristaltic pump is used in operations that require a specific flow rate or variable flow rates at different times.
With respect to claims 5 and 6, Alstad, Nelson, Haegermarck and Zhou disclose the combination as described above. The Alstad pump is fully capable of pumping fluid through either a closed loop or an open loop. Those of ordinary skill would have recognized that these are two basic flow path configurations.
With respect to claims 7 and 8, Alstad, Nelson, Haegermarck and Zhou disclose the combination as described above. Alstad shows in Fig. 4 how a non-zero flow rate is maintained in at least first and second fluid conduits of the pump assembly, wherein the first and second fluid conduits are operated in parallel.
Response to Arguments
In response to Applicant’s amendment filed 04 November 2025, the previous rejections have been withdrawn. However, upon further consideration, a new ground of rejection is made in view of the combination of Alstad with Nelson, Haegermarck and Zhou.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. The Barrett (US 20240426292) reference teaches the state of the art regarding monitoring pump rotational position and torque in order to control flow rate.
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/NATHAN A BOWERS/Primary Examiner, Art Unit 1799