WO2019052110A1 - Fluid infusion device and driving mechanism therefor - Google Patents

Abstract

Disclosed is a driving mechanism (1, 1') for a fluid infusion device, the driving mechanism comprising: a shape memory driving member (11, 11') configured to generate a driving force by means of shape changes; a transmission component (12, 12'), the transmission component (12, 12') having a stress dispersion portion (121, 121'), and the stress dispersion portion (121, 121') being in contact with part of the shape memory driving member (11, 11') so as to disperse the stress on the part of the shape memory driving member (11, 11') during the transferal of the driving force; and an output component (13, 13') cooperating with the transmission component (12, 12') for outputting the driving force to a fluid pushing mechanism (2) of the fluid infusion device. The driving mechanism (1, 1') can prevent the small-radius bending of the shape memory driving member (11, 11'), such that the fatigue lifetime of the shape memory driving member (11, 11') is improved, and the overall service life of the driving mechanism (1, 1') is prolonged.

Description

Fluid infusion device and its driving mechanism

Cross-reference to related applications

This application claims the Chinese patent application filed on Sep. 12, 2017, the application number is 201710818473.6, the invention name is "fluid infusion device and its driving mechanism", and the application number submitted on September 12, 2017 is 201721165362.1, invention The priority of the Chinese patent application is hereby incorporated by reference.

Technical field

The present invention relates to the field of fluid delivery, and in particular to a fluid infusion device and a drive mechanism therefor.

Background technique

Diabetes is a metabolic disease characterized by high blood sugar. Hyperglycemia is generally caused by defects in insulin secretion or its biological effects, or a combination of both. The long-term presence of hyperglycemia in diabetic patients can cause chronic damage and dysfunction in multiple body organs (eg, eyes, kidneys, heart, blood vessels, nervous system, etc.).

The clinical diagnosis of diabetes can be divided into type 1 diabetes and type 2 diabetes. Type 1 diabetes, also known as insulin-dependent diabetes, is usually a disease inherited by a congenital family. Type 1 diabetes is an autoimmune disease in which the body's immune system attacks the beta cells that produce insulin in the body, ultimately leading to the inability to produce insulin in the body. Such patients need to be injected with exogenous insulin to control blood sugar levels in the body. Type 1 diabetes patients typically require 24-hour exposure to an electronic insulin pump, such as the Medtronic Minimed insulin pump. Type 2 diabetes, also known as non-insulin-dependent diabetes, is generally caused by adults, especially obese people, whose condition can lead to weight loss. Possible causes include: insulin resistance, which prevents the body from using insulin effectively; the reduction in insulin secretion does not meet the body's needs. Early type 2 diabetes patients can control and even cure diabetes by improving their lifestyles (eg, healthy eating, moderate exercise, safe weight loss, smoking cessation, and avoidance of secondhand smoke). Most people with type 2 diabetes can control their blood sugar levels through oral hypoglycemic agents or control their blood sugar levels through a phased injection of insulin.

The traditional drug infusion device adopts a driving mechanism in which a motor and a screw are matched. For example, by rotating the lead screw by the motor, the lead screw is moved forward to drive the fluid pushing mechanism to push the fluid out of the reservoir. However, such a drive mechanism requires complicated motor components and transmission components, so that the overall production cost of the infusion device is increased and the weight is greatly increased.

In recent years, in order to reduce the production cost and weight, there has been a driving mechanism that provides a driving force by the deformability of a shape memory alloy (SMA), but a stress pole of a portion of the shape memory alloy that is in contact with the transmission component during its deformation process. Large, easy to break, therefore, these drive mechanisms are usually single-use drive mechanisms, unable to perform long-term, multiple infusions.

Summary of the invention

In order to solve the above technical problems, the present invention provides a drive mechanism for a fluid infusion device that can be reused.

In one aspect, an embodiment of the present invention provides a drive mechanism for a fluid infusion device, comprising: a shape memory drive configured to generate a driving force by a shape change; and a transmission member having a stress dispersion portion And the stress dispersion portion is in contact with a portion of the shape memory drive member to disperse stress of the portion of the shape memory drive member during transmission of the driving force; and an output member opposite to the transmission member Cooperating, a fluid pushing mechanism for outputting the driving force to the fluid infusion device.

In another aspect, an embodiment of the present invention provides a fluid infusion device for administering a patient, the fluid infusion device comprising: a reservoir for storing a fluid; and an infusion line for Delivering fluid in the reservoir to a patient; a fluid pushing mechanism for pushing fluid in the reservoir for delivery to the patient through the infusion line; and a drive mechanism as previously described Driving the fluid pushing mechanism.

According to various embodiments of the present invention, by having the transmission member have a stress dispersion portion to disperse the stress of the shape memory driving member, the small radius bending of the shape memory driving member can be avoided, the fatigue life of the shape memory driving member can be improved, and the driving mechanism can be increased. The overall life span allows it to be reused in fluid infusion devices for extended periods of time.

DRAWINGS

1 is a schematic view of a drive mechanism for a fluid infusion device in accordance with an embodiment of the present invention;

Figure 2 is an enlarged schematic view showing the contact of the shape memory driving member and the stress dispersion portion of Figure 1;

Figure 3 is an enlarged plan view of the electrode of Figure 1;

4 is a schematic view of a drive mechanism for a fluid infusion device in accordance with another embodiment of the present invention;

Figure 5a is an enlarged schematic view showing a contact portion of a shape of the stress dispersion portion and the shape memory driving member of Figure 4;

Figure 5b is a schematic view of the contact portion of Figure 5a after being glued;

Figure 6a is an enlarged schematic view showing the contact of the stress dispersion portion of another shape of Figure 4 with the shape memory drive member;

Figure 6b is a schematic view of the contact portion of Figure 6a after being glued;

Figure 7 is a schematic illustration of a fluid infusion device for administration to a patient in accordance with an embodiment of the present invention.

Among them, the drive mechanism-1/1', shape memory drive-11-11', transmission component -12/12', stress dispersion (first arc surface)-121/121', fork-122/122 ', fork base -123/123', stress dispersion (holding surface) -124', output part -13/13', first electrode -14/14', second electrode - 15/15', Reset member-16, fluid push mechanism-2, reservoir-3, infusion line-4.

Detailed ways

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings. It is to be noted that the invention is not limited to the construction and/or arrangement of the components shown in the drawings, and various combinations of various embodiments of the invention may be made without departing from the spirit of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific embodiment of a driving mechanism for a fluid infusion device of the present invention will be described below with reference to the accompanying drawings.

Embodiments of the present invention provide a drive mechanism for a fluid infusion device that can include, but is not limited to, a shape memory drive, a transmission component, and an output component. Wherein, the shape memory driving member can change the shape, and the driving force is generated by the shape change; the transmission component is used for transmitting the driving force generated by the shape memory driving member; and the output component is matched with the transmission component for outputting the driving force to the fluid transmission. The fluid pushing mechanism of the injection device. The transmission member has a stress dispersion portion that is in contact with a portion of the shape memory drive member to disperse stress of the portion of the shape memory drive member during transmission of the drive force.

[First Embodiment]

1 is a schematic view of a driving mechanism for a fluid infusion device according to an embodiment of the present invention; FIG. 2 is an enlarged schematic view of the shape memory driving member of FIG. 1 in contact with a stress dispersion portion; FIG. An enlarged view of the electrodes in the middle.

As shown in FIGS. 1 and 2, the drive mechanism 1 includes two shape memory drive members 11, a transmission member 12, and an output member 13, wherein the transmission member 12 has a stress dispersion portion 121, a stress dispersion portion 121, and a shape memory drive member 11. A portion of the contact contacts the stress of the portion of the shape memory drive during the transfer of the driving force.

The driving mechanism supplies electric power to the shape memory driving member 11 through the first electrode 14 and the second electrode 15, and heats and cools the shape memory driving member 11 by energizing and de-energizing to change the shape of the shape memory driving member 11. The first electrode 14 is fixedly disposed on the transmission member 12, and the second electrode 15 is fixedly disposed at a position away from the transmission member 12.

In this embodiment, each of the shape memory driving members 11 may be composed of a fixing portion for fixing the shape memory driving member 11 and a working portion for performing shape change, wherein the fixing portion is opposite An end portion, one end portion is fixedly connected to the first electrode 14, and the other end portion is fixedly connected to the second electrode 15; the working portion is a portion other than the opposite end portions, and the shape memory driving member is adjacent to the first electrode 14 The part is the working part, which surrounds the stress dispersion.

In the present embodiment, the stress dispersion portion 121 is a first circular arc surface 121 formed on the transmission member. The circular arc surface is in contact with the working portion of the shape memory driving member to disperse the stress of the working portion, and during the shape change (shrinkage, elongation) of the shape memory driving member, the small radius of the working portion of the shape memory driving member can be avoided. Fold to improve its fatigue life. For example, the circular arc of the first circular arc surface may be any arc between 30 and 90 degrees, such as 30 degrees, 45 degrees, 60 degrees, 90 degrees, etc., to better disperse the shape memory drive member. stress.

In the present embodiment, the shape memory driving member may be in the form of a wire, for example, formed of a shape memory alloy (for example, a nickel-titanium-niobium alloy), and provided with two, which are subjected to heat shrinkage and cooling elongation. Alternatively, the shape memory driving member may also have other shapes, such as strips, strips, etc., or may be formed of other materials having shape memory properties, such as shape memory polymers, etc., the number of which is not limited to 2, for example, may be 1, 3, 4 or more, can be set according to the needs of the required driving force.

As shown in FIG. 2, the first electrode and the second electrode each have a clamping portion that clamps the end of the shape memory driving member, and the clamping portion can be formed by sheet metal to better clamp the end of the shape memory driving member. Department, and achieve electrical conduction and fixation. Alternatively, the first electrode and the second electrode may also fix the end of the shape memory driving member by other means, such as a direct adhesive connection or the like, or may form the clamping portion by other forms. Alternatively, the end of the shape memory drive member may be fixed to the nip by gluing (at the adhesive portion shown in Fig. 1) to further increase the fixing effect while reducing the stress on the fixed portion.

The output member 13 is a ratchet, and the transmission member 12 includes a shift fork 122 and a fork base 123. The fork 122 is fixed to the fork base 123, and is operatively coupled to the ratchet 13, and the stress dispersion portion 121 is disposed on the fork base. 123 is in contact with the shape memory drive member 11. Alternatively, the output member may be other gears, and the transmission member is not limited to the form of a shift fork, and may be any form capable of transmitting a driving force and cooperating with the output member.

When the first electrode 14 and the second electrode 15 are energized, the shape memory driving member 11 is heated, and the working portion thereof is changed from the first shape to the second shape (for example, the length is shortened), and the first circle is passed through the working portion and the stress dispersion portion. The contact of the arc surface 121 drives the fork base to rotate, so that the shift fork moves to push the ratchet to rotate one frame; when the first electrode 14 and the second electrode 15 are powered off, the shape memory driving member 11 is cooled, and the working portion thereof is The second shape is changed to the first shape (for example, the length is elongated), and the contact of the working portion with the first circular arc surface 121 of the stress dispersion portion drives the fork base to return to the original position, so that the shift fork is reset; Heating and cooling causes the ratchet to move intermittently, outputting motion and torque to the fluid pushing mechanism (see Figure 7).

In the present embodiment, in order to facilitate the recovery of the working portion of the shape memory drive member 11, the drive mechanism 1 further includes a reset member 16, which is coupled to the transmission member and configured to cause the shape memory drive member 11 to generate a driving force. The shape is restored from the deformed shape to the shape before the deformation (returning from the second shape to the first shape, for example, elongating the shape memory drive member 11). For example, the reset member can be a reset torsion spring disposed on the fork base 123 to assist in elongating the shape memory drive member 11 to reset the shift fork when the shape memory drive member 11 is cooled.

[Second embodiment]

4 is a schematic view of a driving mechanism for a fluid infusion device according to another embodiment of the present invention; and FIG. 5a is an enlarged schematic view showing a contact portion of a shape of the stress dispersion portion and the shape memory driving member of FIG. Figure 5b is a schematic view of the contact in Figure 5a after being glued.

As shown in FIGS. 4 to 6b, the drive mechanism 1' includes a shape memory drive member 11', a transmission member 12', and an output member 13', wherein the transmission member 12' has a stress dispersion portion, a stress dispersion portion, and a shape memory. A portion of the drive member 11' is in contact to dissipate the stress of the portion of the shape memory drive during the transfer of the drive force.

The driving mechanism supplies power to the shape memory driving member 11' through the first electrode 14' and the second electrode 15' to heat and cool the shape memory driving member 11' to change the shape of the shape memory driving member 11', the first electrode 14' And the second electrode 15' is fixedly disposed at a position away from the transmission member 12'.

In this embodiment, the stress dispersion portion includes a first circular arc surface 121' formed on the transmission member and a retaining portion 124' formed at one end of the first circular arc surface, wherein the circular arc of the first circular arc surface It can be any arc between 30 and 90 degrees.

The shape memory driving member 11' is composed of a fixing portion for fixing the shape memory driving member 11' and a working portion for performing shape change, and the fixing portion includes opposite end portions and is supported in the middle of the surface of the holding portion 124' In one portion, one end is fixedly connected to the first electrode 14', the other end is fixedly connected to the second electrode 15', and the intermediate portion is fixed to the holding portion 124' so that the working portion of the shape memory driving member 11' is along the A circular arc surface 121' at least partially surrounds the transmission member 12'. The shape material of the shape memory driving member 11' and the fixing manner of the opposite ends can be referred to the first embodiment, and details are not described herein. The manner in which the shape memory driving member 11' and the holding portion 124' are fixed is as follows:

As shown in FIG. 5a and FIG. 5b, the surface of the holding portion 124' of the stress dispersion portion may be a circular arc surface (ie, a second circular arc surface) through which a portion of the shape memory driving member 11' in contact with the holding portion 124' may pass. The gluing (adhesive area in Fig. 5b) is fixedly connected, and by the fixing of the glue, the stress of the shape memory driving member in contact with the surface of the holding portion can be reduced, making it difficult to bend. Alternatively, the shape memory drive member may be otherwise secured to the surface of the retaining portion 124', such as a snap or the like.

The output member 13' is a ratchet, and the transmission member 12' includes a shift fork 122' and a fork base 123'. The shift fork 122' is fixed to the fork base 123', and is operatively coupled to the ratchet 13'. The first circular arc surface 121' and the retaining portion 124' are both disposed on the fork base 123' to be in contact with the shape memory driving member 11'. Alternatively, the output member may be other gears, and the transmission member is not limited to the form of a shift fork, and may be any form capable of transmitting a driving force and cooperating with the output member.

When the first electrode 14' and the second electrode 15' are energized, the shape memory driving member 11' is heated, and the working portion thereof is changed from the first shape to the second shape (for example, the length is shortened), and the working portion and the stress dispersion portion are passed through The contact engagement of the first circular arc surface 121 ′ and the holding portion 124 ′ causes the shifting base to rotate, so that the shifting fork moves to push the ratchet to rotate one space; when the first electrode 14 ′ and the second electrode 15 ′ are powered off, The shape memory driving member 11' is cooled, and its working portion is changed from the second shape to the first shape (for example, the length is elongated), and the working portion is in contact with the first circular arc surface 121' and the holding portion 124' of the stress dispersion portion. Cooperating, the fork base is restored to restore the original position, so that the fork is reset; by such circulation heating and cooling, the ratchet intermittently moves, and the movement and torque are output to the fluid pushing mechanism.

In this embodiment, in order to facilitate the restoration of the shape of the working portion of the shape memory drive member, the drive mechanism may further include a reset member (not shown in FIG. 4) connected to the transmission member and configured to cause the shape memory drive member 11' recovers from the deformed shape to the shape before deformation during the generation of the driving force.

[Third embodiment]

Fig. 6a is an enlarged schematic view showing the contact of the stress dispersion portion of the other shape in Fig. 4 with the shape memory driving member, and Fig. 6b is a schematic view showing the contact at the contact portion of Fig. 6a.

In the present embodiment, the rest of the structure of the driving mechanism is the same as that of the second embodiment except for the shape of the holding portion of the stress dispersing portion. For details, refer to the second embodiment, and details are not described herein.

In the present embodiment, as shown in Figs. 6a and 6b, the surface of the holding portion 124' of the stress dispersion portion may be a rectangular surface. The portion of the shape memory driving member 11' that is in contact with the holding portion 124' is fixedly joined by gluing. As shown in the adhesive region shown in FIG. 6b, the glue covers the rectangular surface of the holding portion, and the portion of the shape memory driving member 11' that is in contact with the holding portion 124' is completely wrapped in the glue, so that the glue can be fixed by the glue. The stress on the contact of the shape memory drive member with the rectangular surface is reduced, making it difficult to bend.

Fourth Embodiment

Figure 7 is a schematic illustration of a fluid infusion device for administration to a patient in accordance with an embodiment of the present invention.

As shown in Fig. 7, the fluid infusion device includes a reservoir 3, an infusion line 4, a fluid pushing mechanism 2, and a driving mechanism 1 (for example, the driving mechanism described in the first embodiment). Among them, the accumulator 3 is used to store the fluid to be infused, and may be in various shapes, wherein the stored fluid may be various liquids or the like for administering to a patient. Alternatively, the fluid can be a therapeutic liquid drug such as insulin.

The infusion line 4 is in communication with the reservoir 3 for delivering fluid in the reservoir to a target object (eg, a patient). The fluid push mechanism 2 is used to push fluid in the reservoir 3 for delivery to the patient via the infusion line 4, which may include a piston that is axially movable in the reservoir 3 along the reservoir 3. The drive mechanism 1 is used to drive a fluid pushing mechanism, for example, to move the piston axially in the reservoir 3 such that fluid in the reservoir 3 is delivered to the patient through the infusion line 4.

Alternatively, the fluid infusion device may replace the drive mechanism 1 with a drive mechanism 1' (e.g., the drive mechanism 1' described in the second embodiment or the third embodiment).

For a description of the driving mechanism, please refer to the related description in the foregoing embodiments, and details are not described herein again.

According to the driving mechanism of the present invention, the bending of the small radius of the memory alloy driving member can be avoided, the fatigue life can be improved, and the service life of the driving mechanism can be prolonged, so that the driving mechanism can be used for a long time.

It should be noted that, although the various aspects of the above described devices are described in a specific order and specific structural arrangement, this is for illustrative purposes only and is not limiting of the invention, and the claimed subject matter is not limited to the described order. And structural arrangement. It will be appreciated by those skilled in the art that various modifications can be made in the invention and equivalents can be substituted without departing from the spirit of the invention. Therefore, the claimed subject matter is not limited to the specific embodiments disclosed above, and may include all technical solutions falling within the scope of the claims and equivalent technical solutions. Furthermore, in the claims, all terms are to be understood in the broadest

Claims (17)

1. A driving mechanism for a fluid infusion device, comprising:

   a shape memory drive configured to generate a driving force by a shape change;

   a transmission member having a stress dispersion portion in contact with a portion of the shape memory drive member to disperse stress of the portion of the shape memory drive member during transmission of the driving force ;

   An output member cooperating with the transmission member for outputting the driving force to a fluid pushing mechanism of the fluid infusion device.
2. The driving mechanism according to claim 1, wherein said shape memory driving member is composed of a fixing portion and a working portion, said stress dispersion portion being in contact with a working portion of said shape memory driving member to disperse said work Department of stress.
3. The driving mechanism according to claim 2, wherein the driving mechanism further comprises a first electrode and a second electrode,

   The fixing portion of the shape memory driving member includes two opposite ends, one of which is fixedly connected to the first electrode and the other end is fixedly connected to the second electrode.
4. The drive mechanism according to claim 3, wherein said first electrode and said second electrode have grip portions that grip end portions of said shape memory drive member.
5. The drive mechanism according to claim 4, wherein the clamping portion is formed by sheet metal.
6. The drive mechanism according to claim 5, wherein the end portions of the shape memory driving member are each fixed to the nip portion by gluing.
7. The drive mechanism according to claim 3, wherein said stress dispersion portion is a first circular arc surface formed on said transmission member.
8. The driving mechanism according to claim 7, wherein the arc of the first circular arc has an arc of 30 to 90 degrees.
9. The driving mechanism according to claim 7, wherein said first electrode is fixedly disposed on said transmission member and said second electrode is fixedly disposed at a position away from said transmission member to facilitate said shape memory drive A portion of the piece adjacent to the first electrode surrounds the first arcuate surface.
10. The drive mechanism according to claim 7, wherein said stress dispersion portion further comprises a holding portion formed at one end of said first circular arc surface.
11. The driving mechanism according to claim 10, wherein said first electrode and said second electrode are fixedly disposed at a position away from said transmission member, and said fixing portion of said shape memory drive member is supported by said holding portion An intermediate portion of the surface, the intermediate portion being secured to the retaining portion such that the working portion of the shape memory drive member at least partially surrounds the transmission member along the first arcuate surface.
12. The driving mechanism according to claim 11, wherein a portion of the shape memory driving member that is in contact with a surface of the holding portion is fixedly coupled to a surface of the holding portion by gluing.
13. The drive mechanism according to claim 1, wherein said drive mechanism further comprises a reset member, said reset member being coupled to said transmission member, configured to cause said shape memory drive member to generate a driving force Restores from the deformed shape to the shape before the deformation.
14. The drive mechanism of claim 1 wherein said shape memory drive member is in the form of a strip or a wire.
15. The drive mechanism of claim 1 wherein said shape memory drive member is formed from a shape memory alloy.
16. The driving mechanism according to claim 1, wherein the output member is a ratchet, the transmission member comprises a shift fork and a fork base, and the stress dispersion portion is disposed on the fork base. The shift fork is operatively coupled to the ratchet.
17. A fluid infusion device for administering to a patient, characterized in that the fluid infusion device comprises:

    a reservoir for storing a fluid;

    An infusion line for delivering fluid in the reservoir to a patient;

    a fluid pushing mechanism for pushing fluid in the reservoir for delivery to the patient through the infusion line;

    A drive mechanism according to any one of claims 1 to 16 for driving the fluid pushing mechanism.

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