reciprocating pump

Abstract

A pump suitable for wearable medical devices, such as patch pumps, includes: a chamber (104, 204) capable of axial translation, having an inlet (105, 205) and an outlet (106, 206); a piston (102) or diaphragm (202) rotatably received in the chamber; a first valve (112, 212) between the inlet and the chamber; a second valve (111, 211) between the outlet and the chamber; a cam portion (113, 213) attached to the chamber; a follower (103, 203) attached to the piston or diaphragm and in contact with the cam portion to cause axial translation of the chamber; and a biasing device (107, 207) acting on the chamber to apply a force to the chamber in the axial direction to maintain such contact.

Description

[0001] Case Analysis

[0002] This patent application is a divisional patent application. The original application of this divisional patent application (i.e., the parent application, office file number IIM191985) is a patent application filed on July 19, 2019, with application number 201910652376.3 and subject matter title "reciprocating pump". Technical Field

[0003] In general, this invention relates to a compact, precise, reliable, and low-cost pump suitable for the subcutaneous delivery of liquid pharmaceutical products. More specifically, embodiments of the invention relate to a pump having a piston or diaphragm undergoing rotational motion. The pharmaceutical product to be delivered may be insulin for diabetic patients. Background Technology

[0004] Diabetes is a group of diseases caused by defects in insulin production, insulin action, or both, resulting in high blood sugar levels. There are 23.6 million people with diabetes in the United States, representing 8% of the population. The overall prevalence of diabetes increased by 13.5% compared to the period 2005-2007. Diabetes can lead to serious complications and premature death, but there are well-known products that can help people with diabetes manage the disease and reduce the risk of complications.

[0005] Treatment options for people with diabetes include special diets, oral medications, and / or insulin therapy. The primary goal of diabetes treatment is to control a patient's blood sugar levels to increase the chances of a complication-free life. However, achieving good diabetes management is not always easy while balancing other life needs and circumstances.

[0006] Currently, there are two main methods of daily insulin therapy for type 1 diabetes. The first method involves syringes and insulin pens, requiring a needle prick for each injection, typically three to four times a day. This method is simple to use and relatively inexpensive. The other widely adopted and effective treatment for managing diabetes is the use of an insulin pump. An insulin pump helps users maintain their blood sugar levels within a target range as needed through continuous insulin infusion. By using an insulin pump, users can match insulin therapy to their lifestyle, rather than matching their lifestyle to how insulin injections affect them.

[0007] A conventional insulin pump delivers rapid or short-acting insulin 24 hours a day via a catheter placed under the skin. Insulin doses are typically administered at a basal rate and in bolus doses. Basal insulin is delivered continuously over 24 hours to keep the user's blood sugar levels consistent between meals and overnight. Some insulin pumps can be programmed to adjust the basal rate according to different times of day and night. Bolus doses are typically administered with meals and usually provide a single extra insulin injection to balance carbohydrate consumption. Some conventional insulin pumps allow users to program the volume of bolus doses based on the size or type of meals consumed. Conventional insulin pumps also allow users to take corrective or supplemental bolus doses of insulin to compensate for low blood sugar levels when calculating a meal bolus.

[0008] Compared to other diabetes treatments, conventional insulin pumps offer numerous advantages. Instead of a single injection, the pump delivers insulin over time, resulting in smaller fluctuations in blood glucose levels typically within the range recommended by the American Diabetes Association. Conventional insulin pumps also reduce the number of needle pricks patients must endure and make diabetes management easier and more effective for users, significantly improving their quality of life.

[0009] A major drawback of existing insulin pumps is that, despite their portability, they consist of multiple parts and are cumbersome to use. They are also typically more expensive than other treatments. From a lifestyle perspective, conventional pumps and their associated tubing and infusion kits can be inconvenient and cumbersome for users.

[0010] Unlike conventional infusion pumps, patch pumps are integrated devices that combine most or all fluid components (including a fluid reservoir, pumping mechanism, and automatic cannula insertion mechanism) into a single housing that adhesively attaches to the infusion site on the patient's skin, eliminating the need for separate infusion or tubing kits. Some patch pumps communicate wirelessly with a separate controller (such as those by Insulet Corporation under a trademark). Some are sold as a type of device, while others are completely independent. These devices are frequently replaced, for example, every three days, when the insulin supply runs out.

[0011] Since the patch pump is designed as a stand-alone unit worn by diabetic patients, it is preferably as small as possible so as not to interfere with the user's activities. To minimize user discomfort, it is preferable to minimize the overall size of the patch pump. However, in order to minimize the overall size of the patch pump, the size of its components should be minimized as much as possible.

[0012] Therefore, there is a need in the art for a precise, compact and cost-effective liquid pump that can be provided as part of a disposable system such as a patch pump.

[0013] The purpose of the exemplary embodiments of the present invention is to provide a precise, compact, and cost-effective pump for wearable medical devices, enabling more people with diabetes to benefit from the advantages offered by these devices. Summary of the Invention

[0014] According to one embodiment of the present invention, a pump for pumping liquid is provided, the pump comprising an axially translatable chamber having an inlet and an outlet, a piston or diaphragm rotatably received in the chamber, a first valve between the inlet and the chamber, a second valve between the outlet and the chamber, a cam portion attached to the chamber, a follower attached to the piston and in contact with the cam portion to cause axial translation of the chamber, and a biasing device acting on the chamber to apply a force to the chamber in the axial direction of the chamber to maintain such contact.

[0015] The pump according to one embodiment of the invention has the advantage that a very small and precise amount of liquid medication can be pumped with each rotation of the piston or diaphragm. This enables the very precise injection of small doses of liquid, thus allowing for higher drug concentrations in the reservoir. Higher drug concentrations further reduce the size of the drug reservoir and extend the replacement interval between individual reservoir cartridges. Due to the compact size of the pump according to one embodiment of the invention, it can be used in wearable patch pumps or otherwise positioned near the injection site.

[0016] According to another aspect of the invention, a method for operating a pump is provided, the pump comprising an axially translatable chamber having an inlet and an outlet, a piston or diaphragm rotatably received in the chamber, a first valve between the inlet and the chamber, and a second valve between the outlet and the chamber, the method comprising the steps of: rotating the piston or diaphragm to convert the rotation of the piston or diaphragm into axial reciprocating motion of the chamber, and opening and closing the first and second valves to allow liquid to be drawn into and discharged from the chamber through the piston or diaphragm. Attached Figure Description

[0017] The above and other exemplary objects, features and advantages of the present invention will become more apparent from the following description of certain exemplary embodiments thereof, taken in conjunction with the accompanying drawings, in which:

[0018] Figure 1A and 1B These are cross-sectional and partial upper perspective views of the pump system according to the first embodiment of the present invention;

[0019] Figure 2A and 2BThese are cross-sectional and partial upper perspective views of a pump system according to a second embodiment of the present invention;

[0020] Figure 3A and 3B This is a cross-sectional view of a pump system according to a third embodiment of the present invention, showing different parts during the pumping cycle;

[0021] Figure 3C yes Figure 3A and 3B A partial upper 3D view of the pump system;

[0022] Figure 4 yes Figure 1A-1B and Figure 2A-2B The illustration shows the angular displacement of the inlet and outlet valves relative to the rotating piston in the embodiment; while

[0023] Figure 5 yes Figures 3A-3C The illustration shows the state of the inlet valve, outlet valve, and diaphragm relative to the rotating rod in the embodiment.

[0024] In all the accompanying drawings, similar reference numerals will be understood to refer to similar elements, features, and structures. Detailed Implementation

[0025] The illustrations in this specification are provided to aid in understanding exemplary embodiments of the invention, and are described with reference to the accompanying drawings. For clarity and brevity, descriptions of well-known functions and constructions have been omitted.

[0026] like Figure 1A and 1B As shown, a pump according to a first embodiment of the present invention is illustrated in cross-section and a partial upper perspective view. The pump includes a chamber 104 in which a piston 102 is rotatably received. A shaft or piston rod 101 is rigidly connected to the piston 102. A column 103 is rigidly connected to the shaft 101 and serves as a follower to the cam portion for contacting a cam surface 113 extending around the top edge of the chamber 104. In this embodiment, the piston 102 rotates only within the chamber 104 without any movement in the axial direction of the chamber 104. Instead, the chamber 104 reciprocates axially as the rotation of the shaft 101 is converted into axial movement of the chamber 104 via the cam surface 113 and the column 103. This design is less mechanically complex than conventional designs because it does not require a rotary linkage capable of axial sliding. This design also improves reliability and reduces manufacturing costs. The advantages of this design also apply to the following... Figure 2A-2B Examples of 3A-3C.

[0027] Chamber 104 includes an inlet 105, an outlet 106, an inlet valve 112, and an outlet valve 111. Valves 111 and 112 may be self-starting check valves or externally controlled valves operated sequentially by a suitable mechanical linkage or electrical control system (not shown). A biasing device 107, such as a helical spring, acts on chamber 104 to apply an upward biasing force at the bottom of chamber 104 in the axial direction. The biasing device 107 maintains constant contact between the pin 103 and the cam surface 113, causing chamber 104 to translate vertically along its axial direction. The rotational motion of the pin 103 and piston 102 is converted into linear motion of chamber 104. As the pin 103 rotates, it pushes against the cam surface 113 of chamber 104.

[0028] The opening and closing of valves 111 and 112 are synchronized with the rotation of column 103. Inlet valve 112 and outlet valve 111 open and close according to the relative displacement between column 103 and cam surface 113 to allow liquid to flow into and out of chamber 104.

[0029] The biasing device 107 maintains appropriate pressure to keep constant contact between the column 103 and the cam surface 113 throughout the pumping cycle. The pumping process itself is repeated to maintain a stable flow of fluid through the chamber 104.

[0030] Figure 2A and 2B This is a cross-sectional and partial upper perspective view of a pump according to another embodiment of the present invention. Similar to... Figure 1A and 1B The biasing device 107 acts on the chamber 104 to apply a force to the chamber 104 in the axial direction to maintain constant contact between the column 103 and the cam surface 113. The interaction between the column 103 and the cam surface 113 causes the chamber 104 to translate vertically along the axial direction of the chamber 104.

[0031] When column 103 rotates to a certain position, cam surface 113 and chamber 104 are pushed downwards by column 103, triggering pinch valve 109 to close flexible outlet pipe 106. When column rotates to another position, chamber 104 is pushed upwards by bias device 107, triggering pinch valve 108 to close flexible inlet pipe 105. The pumping process itself repeats to maintain a stable flow of fluid through chamber 104.

[0032] exist Figures 3A-3CThe pump according to a third embodiment of the present invention is shown in cross-section and partial upper perspective view. The pump includes a chamber 204 in which a flexible diaphragm 202 is rotatably received. A shaft 201 is rigidly connected to the diaphragm 202. A column 203 is rigidly connected to the shaft 201. Similar to the previous embodiment, the diaphragm 202 rotates only within the chamber 204 and does not participate in axial movement. The chamber 204 includes an inlet 205, an outlet 206, an inlet valve 212, and an outlet valve 211. A biasing device 207, such as a helical spring, acts on the chamber 204 to apply a biasing force to the chamber 204 in the axial direction. The biasing device 207 maintains constant contact between the column 203 and the cam surface 213. Axial translation of the chamber 204 is coordinated with the opening and closing of the inlet valve 212 and the outlet valve 211. Valves 211 and 212 may be self-starting check valves or external control valves operated sequentially by a suitable mechanical linkage or electrical control system (not shown). The opening and closing of inlet valve 212 and outlet valve 211 may be mechanically synchronized with the displacement of column 203 and cam surface 213.

[0033] When the cam surface 213 is pushed upward by the biasing device 207, the outlet valve 211 opens to allow fluid to be pumped out of the chamber 204. The diaphragm is in a position as... Figure 3A The downward deflection position is shown. When the cam surface 213 is pushed downward by the column 203, the inlet valve 212 opens to allow fluid to be pumped into the chamber 204. The diaphragm 202 is in the position shown. Figure 3B The upward flexing position is shown.

[0034] Figure 4 Is Figure 1A-1B The illustration shows the angular displacement of the inlet and outlet valves relative to column 103 in embodiments 2A-2B. In the first angular displacement A, the inlet valve is open and the outlet valve is closed to allow fluid to flow into the chamber. In the second angular displacement B, both the inlet and outlet valves are closed. In the third angular displacement C, the inlet valve is closed and the outlet valve is open to allow fluid to flow out of the chamber. In the fourth angular displacement D, both the inlet and outlet valves are closed. Column 103 then rotates back to the first angular displacement A, starting a new pumping cycle. The pumping cycle is repeated to allow fluid to be continuously pumped into and out of the pump chamber 104.

[0035] Figure 5 yes Figures 3A-3CThe illustration shows the states of the inlet and outlet valves and the diaphragm 202 relative to the column 203 in the embodiment. In the first angular displacement A, the diaphragm 202 flexes downward, the inlet valve 212 is closed, and the outlet valve 211 is open to allow fluid to flow out of the chamber. In the second angular displacement B, both the inlet valve 212 and the outlet valve 211 are closed. In the third angular displacement C, the diaphragm 202 flexes upward, the inlet valve 212 is open, and the outlet valve 211 is closed to allow fluid to flow into the chamber. In the fourth angular displacement D, both the inlet valve 212 and the outlet valve 211 are closed. The column 203 then rotates back to the first angular displacement 610, starting a new pumping cycle. The pumping cycle is repeated to allow fluid to be continuously pumped into and out of the pump chamber 204.

[0036] Although the invention has been shown and described with reference to specific illustrative embodiments, the invention is not limited to the illustrative embodiments, but only to the appended claims and their equivalents. It should be understood that those skilled in the art can change or modify the illustrative embodiments without departing from the scope of the invention. Furthermore, features of various embodiments can be combined with each other to form new embodiments without departing from the scope of the invention.

Claims

1. A pump system for pumping liquids, the pump system comprising: A chamber capable of axial translation, the chamber having a cam surface, an inlet valve, and an outlet valve; A diaphragm, the diaphragm being received within the chamber; A follower, which is coupled to the diaphragm and contacts the cam surface, so as to cause the chamber to translate axially by means of the rotation of the follower relative to the chamber; and In this configuration, the chamber is biased relative to the pump system in the axial direction to maintain contact between the follower and the cam surface of the chamber.

2. The pump system according to claim 1, wherein, The diaphragm is flexible and has an outer edge that is attached to the inner surface of the chamber.

3. The pump system according to claim 2, wherein, The pump system also includes a shaft that extends axially from the diaphragm, and wherein the follower is coupled to the shaft.

4. The pump system according to claim 3, wherein, The follower extends radially outward from the shaft and is oriented to contact the cam surface of the chamber.

5. The pump system according to claim 1, wherein, The diaphragm is rotatable within the chamber.

6. The pump system according to claim 1, wherein, The follower extends radially outward relative to the diaphragm.

7. The pump system according to claim 6, wherein, The cam surface faces outward along the axial direction relative to the chamber, and the follower is oriented to contact the cam surface of the chamber.

8. The pump system according to claim 1, wherein, The diaphragm is flexible and has an outer edge rotatably coupled to the inner surface of the chamber. The pump system has a shaft extending axially from the central portion of the diaphragm. A follower is coupled to the shaft, wherein rotation of the follower and the shaft relative to the chamber causes the central portion of the diaphragm to move between a first configuration and a second configuration.

9. A pump system for pumping liquids, the pump system comprising: A chamber capable of axial translation, the chamber having a cam surface, an inlet, and an outlet; A piston, received in the chamber, is fixed in an axial position relative to the pump system; the piston has a follower that contacts the cam surface to cause the chamber to translate axially by means of rotation of the piston relative to the chamber. and The chamber is biased in the axial direction to maintain contact between the follower and the cam surface of the chamber.

10. The pump system according to claim 9, wherein, The inlet includes an inlet valve, and the outlet includes an outlet valve.

11. The pump system according to claim 10, wherein, The inlet valve and the outlet valve include check valves.

12. The pump system according to claim 10, wherein, The inlet valve and outlet valve include external control valves operated by mechanical linkage devices or by electronic control systems.

13. The pump system according to claim 10, wherein, The inlet and outlet valves include pinch valves.

14. The pump system according to claim 10, wherein, The inlet valve includes a flexible inlet pipe, wherein when the chamber is in a first position, the pinch valve closes the flexible inlet pipe, and the outlet valve includes a flexible outlet pipe, wherein when the chamber is in a second position, the pinch valve closes the flexible outlet pipe.

15. The pump system according to claim 9, wherein, The chamber is biased by a biasing member, which includes a spring.

16. The pump system according to claim 9, wherein, The cam surface is located on the axial edge of the chamber.

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