Infusion pump

Patent metadata

Field	Value
Publication number	US-9463275-B2
Application number	US-201214346828-A
Country	US
Kind code	B2
Filing date	Sep 11, 2012
Priority date	Sep 26, 2011
Publication date	Oct 11, 2016
Grant date	Oct 11, 2016

Abstract

An infusion pump has a primary finger with an inclined surface, which is obliquely inclined to an advancing and retracting direction, and a secondary finger with an inclined surface, which is slidable relative to the inclined surface of the primary finger. When the primary finger is advanced, the secondary finger is retracted in proportion to the variation (increasing) in an entire width of an infusion tube, and when the primary finger is retracted, the secondary finger is advanced in proportion the variation (decreasing) in the entire width of the infusion tube. This configuration can suppress the occurrence of any gap between a tip surface of the secondary finger and an outer peripheral surface of the infusion tube in the advancing and retracting process of the primary finger. Consequently, this prevents the infusion tube from meandering, and suppresses the reduction in the accuracy of the rate of infusion.

First claim

The invention claimed is:

1. An infusion pump comprising a pump mechanism which presses an infusion tube to deliver an amount of infusion solution within the infusion tube,
wherein the pump mechanism comprises:
a primary finger capable of being advanced and retracted in an advancing and retracting direction relative to the infusion tube, the primary finger having a pair of tapered inclined surfaces opposingly inclined to the advancing and retracting direction, and the primary finger pressing the infusion tube when the primary finger is advanced;
driving means which moves the primary finger in the advancing and retracting direction; and
a pair of secondary fingers each capable of being advanced and retracted only in one direction orthogonal to the advancing and retracting direction of the primary finger, each of the pair of secondary fingers having an inclined surface arranged to contact and slidable relative to one of the tapered inclined surfaces of the primary finger,

wherein when the primary finger is advanced and retracted, the tapered inclined surfaces of the primary finger and the inclined surfaces of the secondary fingers are arranged to slide in contact with each other, thereby causing the secondary fingers to move in conjunction with the movement of the primary finger in the directions orthogonal to the advancing and retracting direction of the primary finger,
wherein, when the primary finger is advanced, the secondary fingers are retracted in proportion to a variation in an entire width of the infusion tube, and when the primary finger is retracted, the secondary fingers are advanced in proportion to the variation in the entire width of the infusion tube, and
wherein, with an angle of inclination for the tapered inclined surfaces of the primary finger relative to a central axis being θ1, θ1 is set to satisfy θ1=tan −1 (π/4−½).

2. The infusion pump according to claim 1 , further comprising
a resilient member which presses the inclined surfaces of the secondary fingers against the tapered inclined surfaces of the primary finger, wherein the tapered inclined surfaces of the primary finger and the inclined surfaces of the secondary fingers are configured to slide relative to each other due to a resilient force of the resilient member when the primary finger is retracted.

3. The infusion pump according to claim 1 , further comprising
connecting means which slidably connects the primary finger and the secondary fingers,
wherein the tapered inclined surfaces of the primary finger and the inclined surfaces of the secondary fingers are configured to slide relative to each other due to the connection of the connecting means when the primary finger is retracted.

4. The infusion pump according to claim 1 ,
wherein the pump mechanism further comprises an upstream side valve finger which occludes openably/closably the infusion tube on an upstream side of an infusion delivery direction of the primary finger, and a downstream side valve finger which occludes openably/closably the infusion tube on a downstream side of an infusion delivery direction of the primary finger.

5. The infusion pump according to claim 1 ,
wherein the primary finger is a plurality of primary fingers capable of being advanced and retracted relative to the infusion tube, the plurality of primary fingers pressing the infusion tube when the plurality of primary fingers is advanced, and
wherein the driving means individually moves the plurality of primary fingers in the advancing and retracting direction, the amount of infusion solution being sent out in a peristaltic motion by driving each of the plurality of primary fingers to advance and retract to the infusion tube, wherein the pair of secondary fingers is a plurality of secondary fingers provided for the primary fingers of the pump mechanism.

6. An infusion pump comprising a pump mechanism which presses an infusion tube to deliver an amount of infusion solution within the infusion tube,
wherein the pump mechanism comprises:
a primary finger capable of being advanced and retracted relative to the infusion tube, the primary finger pressing the infusion tube when the primary finger is advanced;
driving means which moves the primary finger in the advancing and retracting direction; and
a secondary finger capable of being advanced and retracted only in one direction orthogonal to the advancing and retracting direction of the primary finger,

wherein the primary finger has an inclined surface which is obliquely inclined to the advancing and retracting direction, and the secondary finger has an inclined surface which is arranged to contact the inclined surface of the primary finger,
wherein when the primary finger is advanced and retracted, the inclined surface of the primary finger and the inclined surface of the secondary finger are arranged to slide in contact with each other, thereby causing the secondary finger to move in conjunction with the movement of the primary finger in the direction orthogonal to the advancing and retracting direction of the primary finger,
wherein, when the primary finger is advanced, the secondary finger is retracted in proportion to a variation in an entire width of the infusion tube, and when the primary finger is retracted, the secondary finger is advanced in proportion to the variation in the entire width of the infusion tube,
wherein the inclined surface of the primary finger is an inclined surface inclined to the advancing and retracting direction, and the secondary finger is a single secondary finger with an inclined surface slidable relative to the inclined surface of the primary finger, and
wherein, with an angle of inclination for the inclined surface of the primary finger relative to a central axis being θ2, θ2 is set to satisfy θ2=tan −1 (π/2−1).

7. The infusion pump according to claim 6 , further comprising
a resilient member which presses the inclined surface of the secondary finger against the inclined surface of the primary finger, wherein the inclined surface of the primary finger and the inclined surface of the secondary finger are configured to slide relative to each other due to a resilient force of the resilient member when the primary finger is retracted.

8. The infusion pump according to claim 6 , further comprising
connecting means which slidably connects the primary finger and the secondary finger,
wherein the inclined surface of the primary finger and the inclined surface of the secondary finger are configured to slide relative to each other due to the connection of the connecting means when the primary finger is retracted.

9. The infusion pump according to claim 6 ,
wherein the pump mechanism further comprises an upstream side valve finger which occludes openably/closably the infusion tube on an upstream side of an infusion delivery direction of the primary finger, and a downstream side valve finger which occludes openably/closably the infusion tube on a downstream side of an infusion delivery direction of the primary finger.

10. The infusion pump according to claim 6 ,
wherein the primary finger is a plurality of primary fingers capable of being advanced and retracted relative to the infusion tube, the plurality of primary fingers pressing the infusion tube when the plurality of primary fingers is advanced, and
wherein the driving means individually moves the plurality of primary fingers in the advancing and retracting direction, the amount of infusion solution being sent out in a peristaltic motion by driving each of the plurality of primary fingers to advance and retract to the infusion tube, wherein the secondary finger is a plurality of secondary fingers provided for the primary fingers of the pump mechanism.

Assignees

• Ueda Mitsutaka
• AKAI Ryoichi
• Takahashi Hidenori
• Nipro Corp

Inventors

• Ueda Mitsutaka
• AKAI Ryoichi
• Takahashi Hidenori

Classifications

• A61M5/14212

  Pumping with an aspiration and an expulsion action · CPC title

• A61M5/16813 Primary

  by controlling the degree of opening of the flow line · CPC title

• F04B43/082

  the tubular flexible member being pressed against a wall by a number of elements, each having an alternating movement in a direction perpendicular to the axes of the tubular member and each having its own driving mechanism · CPC title

• A61M5/14224

  Diaphragm type · CPC title

• A61M5/14228 Primary

  with linear peristaltic action, i.e. comprising at least three pressurising members or a helical member · CPC title