US-12624683-B2 - Reciprocating pump

US12624683B2US 12624683 B2US12624683 B2US 12624683B2US-12624683-B2

Abstract

A pump suitable for use in a wearable medical device, such as a patch pump, comprises an axially translatable chamber with an inlet and an outlet, a piston or a 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 affixed to the chamber, a follower affixed to the piston and in contact with the cam for axially translating the chamber, and a biasing means acting on the chamber for applying a force on the chamber in an axial direction of the chamber to maintain such contact.

Inventors

J. Richard Gyory

Assignees

BECTON, DICKINSON AND COMPANY

Dates

Publication Date: 20260512
Application Date: 20211019

Claims (9)

1 . A pump system for the pumping of a liquid, the pump system comprising: an axially translatable chamber having a cam surface, an inlet valve and an outlet valve; a diaphragm received in the chamber; a follower coupled to the diaphragm and in contact with the cam surface for axially translating the chamber by rotation of said follower relative to said chamber; and where said chamber is biased in an axial direction of the chamber with respect to the pump system to maintain contact between the follower and the cam surface of the chamber; wherein said diaphragm is flexible and has an outer edge rotatably coupled to an inner surface of said chamber, and said pump system further comprises a post, said diaphragm covering an axial end of said post.
2 . The pump system according to claim 1 , wherein the inlet valve and the outlet valve comprise check valves.
3 . The pump system according to claim 1 , wherein the inlet valve and the outlet valve comprise externally controlled valves that are operated by a mechanical linkage or operated an electrical control system.
4 . The pump system according to claim 1 , wherein the inlet valve and said outlet valve comprise pinch valves.
5 . The pump system according to claim 1 , wherein the chamber is biased by a biasing member comprising a spring.
6 . The pump system according to claim 1 , wherein the cam surface is on an axial surface of the chamber.
7 . The pump system according to claim 1 , wherein said diaphragm is flexible and has an outer edge coupled to an inner radial surface of said chamber, said diaphragm forming an axial barrier of said chamber.
8 . The pump system according to claim 1 , wherein said follower extends radially outward from said post and is oriented for contacting the cam surface of the chamber.
9 . The pump system of claim 1 , wherein rotation of said follower and said post relative to said chamber moves said center portion of said diaphragm between a first configuration and a second configuration.

Description

This application is a continuation application of U.S. Ser. No. 16/041,068 filed on Jul. 20, 2018, which is hereby incorporated by reference in its entirety. FIELD OF THE INVENTION The present invention relates generally to a compact, precise, reliable and low cost pump suitable for subcutaneous delivery of a liquid pharmaceutical product. More particularly, embodiments of the present invention relate to a pump with a piston or diaphragm that undergoes a rotational motion. The pharmaceutical product to be delivered may be insulin for diabetic patients. BACKGROUND OF THE INVENTION Diabetes is a group of diseases marked by high levels of blood glucose resulting from defects in insulin production, insulin action, or both. There are 23.6 million people in the United States, or 8% of the population, who have diabetes. The total prevalence of diabetes has increased 13.5% since the 2005-2007 time period. Diabetes can lead to serious complications and premature death, but there are well-known products available for people with diabetes to help control the disease and lower the risk of complications. Treatment options for people with diabetes include specialized diets, oral medications and/or insulin therapy. The primary goal for diabetes treatment is to control the patient's blood glucose (sugar) level in order to increase the chances of a complication-free life. It is not always easy, however, to achieve good diabetes management, while balancing other life demands and circumstances. Currently, there are two principal modes of daily insulin therapy for the treatment of type 1 diabetes. The first mode includes syringes and insulin pens that require a needle stick at each injection, typically three to four times per day that are simple to use and relatively low in cost. Another widely adopted and effective method of treatment for managing diabetes is the use of an insulin pump. Insulin pumps can help the user keep blood glucose levels within target ranges based on individual needs, by continuous infusion of insulin. By using an insulin pump, the user can match insulin therapy to lifestyle, rather than matching lifestyle to how an insulin injection is working for the user. Conventional insulin pumps are capable of delivering rapid or short-acting insulin 24 hours a day through a catheter placed under the skin. Insulin doses are typically administered at a basal rate and in a bolus dose. Basal insulin is delivered continuously over 24 hours, and keeps the user's blood glucose levels in a consistent range between meals and overnight. Some insulin pumps are capable of programming the basal rate of insulin to vary according to the different times of the day and night. Bolus doses are typically administered when the user takes a meal, and generally provide a single additional insulin injection to balance the carbohydrates consumed. Some conventional insulin pumps enable the user to program the volume of the bolus dose in accordance with the size or type of the meal consumed. Conventional insulin pumps also enable a user to take in a correctional or supplemental bolus of insulin to compensate for a low blood glucose level at the time the user is calculating a meal bolus. There are many advantages of conventional insulin pumps over other methods of diabetes treatment. Insulin pumps deliver insulin over time rather than in single injections and thus typically result in less variation within the blood glucose range that is recommended by the American Diabetes Association. Conventional insulin pumps also reduce the number of needle sticks which the patient must endure, and make diabetes management easier and more effective for the user, thus considerably enhancing the quality of the user's life. A major disadvantage of existing insulin pumps is that, in spite of their portability, they include multiple components and can be heavy and cumbersome to use. They are also typically more expensive than other methods of treatment. From a lifestyle standpoint, the conventional pump with its associated tubing and infusion set can be inconvenient and bothersome for the user. Unlike a conventional infusion pump, a patch pump is an integrated device that combines most or all of the fluidic components, including the fluid reservoir, pumping mechanism and a mechanism for automatically inserting the cannula, in a single housing which is adhesively attached to an infusion site on the patient's skin, and does not require the use of a separate infusion or tubing set. Some patch pumps wirelessly communicate with a separate controller (as in one device sold by Insulet Corporation under the brand name OmniPod®), while others are completely self-contained. Such devices are replaced on a frequent basis, such as every three days, when the insulin supply is exhausted. As a patch pump is designed to be a self-contained unit that is worn by the diabetic patient, it is preferable to be as small as possible so that it does not interfere with the activities