Driving assembly and device for assisting heart in functional failure

Abstract

The utility model relates to a driving assembly and a device for assisting a heart in functional failure, and belongs to the technical field of medical instruments. According to the driving assembly, in the radial direction of the rotation axis, a first air gap is formed between the motor and the radiator, a second air gap is formed between the bearing chamber and the radiator, and the first air gap is set to be larger than the second air gap, namely, the first air gap is larger than the second air gap. The heat exchange space of the part (motor) with larger heat quantity is set to be larger than the heat exchange space of the part (bearing chamber) with smaller heat quantity, so that the heat dissipation speed of the radiator part positioned on the motor side and the heat dissipation speed of the radiator part positioned on the bearing chamber side are balanced, and the surface temperature of the radiator is uniformly distributed.

Description

Technical Field

[0001] The present application relates to a driving component and a device for assisting the heart when functional failure occurs, belonging to the technical field of medical devices. Background Art

[0002] Heart failure is a life-threatening disease with a one-year mortality rate of approximately 75% once it deteriorates to the advanced stage. Given the limited number of heart donors for advanced heart failure, ventricular assist device technology has become a viable treatment or alternative treatment option between patients and transplantation.

[0003] As a ventricular assist device, the catheter pump delivers the pump body into the ventricle through interventional means, and uses the rotation of the impeller to assist in pumping blood. The catheter pump is driven by a drive assembly, such as the drive assembly disclosed in a device for assisting the heart in the event of functional failure disclosed in Chinese patent application No. 202210862742.X, which includes a motor and a bearing chamber connected to the far end of the motor, and the bearing chamber is located in the motor housing. Heat dissipation fins are formed on the motor housing to dissipate heat from the motor. However, in the prior art, since the heat transferred to the motor housing by the motor and the bearing chamber is different, the drive assembly has the problem of uneven surface temperature of the heat dissipation fins. When the surface temperature of the heat dissipation fins is uneven, the local surface temperature will be too high, affecting the hand-held operation of medical staff. Utility Model Content

[0004] The utility model aims to provide a driving component with more uniform heat dissipation.

[0005] In order to achieve the above object, the utility model provides the following technical solution: a driving assembly for driving a catheter pump to work, the driving assembly comprising:

[0006] a motor having an output shaft rotatable about a rotation axis;

[0007] a driving member connected to the output shaft of the motor to transmit the driving force of the motor; and a bearing chamber for rotatably supporting the driving member;

[0008] Wherein, at least part of the outer shell of the drive assembly is formed as a radiator, which covers at least a portion of the motor and at least a portion of the bearing chamber; in a radial direction perpendicular to the rotation axis, a first air gap is formed between the surface of the motor facing the radiator and the radiator, and in the radial direction, a second air gap is formed between the surface of the bearing chamber facing the radiator and the radiator, and the first air gap is larger than the second air gap.

[0009] Furthermore, the driving assembly further comprises a bearing chamber cover for engaging with the catheter pump, the bearing chamber cover being connected to an end surface of the bearing chamber away from the motor, and the bearing chamber cover at least covers a portion of the active member;

[0010] In the radial direction, a third air gap is formed between the surface of the bearing chamber cover facing the radiator and the radiator, and the first air gap is larger than the third air gap.

[0011] Further, in an axial direction parallel to the rotation axis, a fourth air gap is formed between an end surface of the bearing chamber close to the motor and the radiator, and the fourth air gap is fluidly connected to the first air gap and the second air gap, respectively.

[0012] Further, in the axial direction parallel to the rotation axis, a fifth air gap is formed between an end surface of the bearing chamber away from the motor and the heat sink, and the fifth air gap is fluidly connected to the second air gap and the third air gap, respectively.

[0013] Furthermore, the motor and the bearing chamber are at least partially fitted together or connected via a connection structure that can achieve heat conduction.

[0014] Furthermore, the motor is fixed to the housing of the driving assembly through a bearing chamber.

[0015] Furthermore, a plurality of heat dissipation fins are arranged on the outer surface of the radiator.

[0016] Furthermore, the thickness of the heat dissipation fins is between 1-4 mm.

[0017] Furthermore, the distance between adjacent heat dissipation fins is between 2-4 mm.

[0018] The utility model also provides a device for assisting the heart when functional failure occurs, comprising the drive assembly and the catheter pump in the above optional solution;

[0019] The catheter pump comprises: a catheter, a driving shaft passing through the catheter, and a pump head connected to the distal end of the catheter;

[0020] The pump head comprises: a pump housing having an inlet and an outlet, and an impeller received in the pump housing;

[0021] The distal end of the drive shaft is connected to the impeller, and the proximal end thereof is connected to a driven member, and the driven member is detachably coupled to the driving member to transmit the driving force of the motor to the impeller, and the impeller is driven to rotate, thereby sucking blood from the inlet into the pump housing and discharging it from the outlet.

[0022] The beneficial effects of the utility model are:

[0023] The drive assembly of the utility model forms a first air gap between the motor and the radiator and a second air gap between the bearing chamber and the radiator in the radial direction of the rotation axis, and the first air gap is set to be larger than the second air gap, that is, by setting the heat exchange space of the part with larger heat generation (motor) to be larger than the heat exchange space of the part with relatively smaller heat generation (bearing chamber), the heat dissipation rate of the radiator part located on the motor side and the heat dissipation rate of the radiator part located on the bearing chamber side are balanced, so that the surface temperature of the radiator is evenly distributed. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the structure of the driving assembly of an embodiment of the utility model;

[0025] Figure 2 This is a schematic diagram of the structure of a device for assisting the heart when heart function failure occurs according to an embodiment of the utility model. DETAILED DESCRIPTION

[0026] The driving assembly of the embodiment of the utility model is used to drive the catheter pump to work, and the catheter pump can at least partially assist the heart's blood pumping function to achieve the effect of at least partially alleviating the heart's burden.

[0027] See also Figure 1 The drive assembly 10 includes a housing 1, a motor 2 housed in the housing 1, an active member 3 driven by the motor 2, and a bearing chamber 4 for rotatably supporting the active member 3. The structure of the motor 2 can adopt the existing technology and will not be described in detail here. It has an output shaft (not numbered) that can rotate around a rotation axis xx. The rotation axis xx is as shown in FIG. Figure 1 As shown by the dashed line. In the present embodiment, the rotation axis xx is colinear with the axis of the housing 1, the central axis of the active component 3, and the central axis of the bearing chamber 4. The active component 3 is connected to the output shaft of the motor 2 to transmit the driving force of the motor 2. Specifically, the active component 3 transmits the driving force of the motor 2 to the catheter pump. The bearing chamber 4 is located in the housing 1. The structure of the bearing chamber 4 can also adopt the existing technology. Generally speaking, the connecting end of the active component 3 connected to the output shaft of the motor 2 extends into the bearing chamber 4. The bearing chamber 4 is provided with a bearing 5 assembled between the bearing chamber 4 and the connecting end, so as to realize rotatable support of the connecting end of the active component 3 through the bearing 5.

[0028] The housing 1 is at least partially formed as a heat sink 12 . Specifically, the housing 1 includes a motor housing 11 and a heat sink 12 disposed on the motor housing 11 . The motor housing 11 and the heat sink 12 are surrounded to form a receiving cavity 13 .

[0029] The motor 2 and the bearing chamber 4 are arranged along the axial direction of the rotation axis xx. In the radial direction of the rotation axis xx, the radiator 12 is located on one side of the motor 2 and the bearing chamber 4. In this embodiment, along the axial direction of the rotation axis xx, the radiator 12 completely covers the motor 2 and the bearing chamber 4. Different air gaps are formed between the radiator 12 and the motor 2 and the bearing chamber 4.

[0030] In detail, in the radial direction perpendicular to the rotation axis xx, a first air gap 61 is formed between the surface of the motor 2 facing the radiator 12 and the radiator 12; in the radial direction, a second air gap 62 is formed between the surface of the bearing chamber 4 facing the radiator 12 and the radiator 12. The first air gap 61 is larger than the second air gap 62.

[0031] When the drive assembly 10 is working, the main working unit is the motor 2, and the heat generated by the motor 2 is the main heat generated by the drive assembly 10. Under the drive of the motor 2, the bearing 5 in the bearing chamber 4 will also generate heat, and the heat generated by the bearing 5 is mainly absorbed by the bearing chamber 4 and transferred from the bearing chamber 4 to the housing 1. The heat generated by the motor 2 is greater than the heat of the bearing chamber 4.

[0032] In the radial direction of the rotation axis xx, a first air gap 61 is formed between the motor 2 and the radiator 12, and a second air gap 62 is formed between the bearing chamber 4 and the radiator 12, and the first air gap 61 is set to be larger than the second air gap 62, that is, the heat exchange space of the part with larger heat generation (motor 2) is set to be larger than the heat exchange space of the part with relatively smaller heat generation (bearing chamber 4), so as to balance the heat dissipation rate of the radiator 12 part located on the motor 2 side and the heat dissipation rate of the radiator 12 part located on the bearing chamber 4 side, so that the surface temperature distribution of the radiator 12 is uniform.

[0033] In other embodiments, the radiator 12 may also partially cover the motor 2 and / or partially cover the bearing chamber 4. The area covered by the radiator 12 for the motor 2, the area covered for the bearing chamber 4, and whether the covered areas are the same are determined according to actual conditions and are not specified in detail in this application.

[0034] In one embodiment, the motor housing 11 and the radiator 12 are separate structures, and the two are assembled by means of a clamping connection or a fastener connection. For example, for the sake of convenience, the following is a Figure 1 The state shown is the reference direction to explain the structure of the motor housing 11. Figure 1The direction indicated by the middle arrow a1-a2 is the up-down direction, and the direction indicated by the arrow b1-b2 is the left-right direction. The motor housing 11 has a lower wall 111, a front side wall (not shown) and a rear side wall (not shown) that are arranged oppositely, and a left side wall 112. The upper side of the motor housing 11 is an installation opening (not numbered), and the right side is an opening (not numbered), and the radiator 12 is installed in the installation opening. The motor housing 11 and the radiator 12 are arranged as a split structure, which facilitates the assembly convenience of the motor 2 and the bearing chamber 4.

[0035] In one embodiment, a plurality of heat dissipation fins 122 are disposed on the outer surface of the heat sink 12 to further improve the heat dissipation performance. In this embodiment, the heat sink 12 has a main body 121 installed in the installation opening to close the installation opening and a plurality of heat dissipation fins 122 formed on the outer surface of the main body 121. The heat dissipation fins 122 are sheet-shaped bodies extending along the width direction of the heat sink 12, and the heat dissipation fins 122 are vertically or quasi-vertically disposed on the main body 121. The cooling airflow flows between two adjacent heat dissipation fins 122 to take away the heat of the heat sink 12.

[0036] It should be noted that in the prior art, the heat sink fins 122 are usually made of metal materials (such as aluminum). Since the heat sink fins 122 are sheet-shaped, if the thickness of the heat sink fins 122 is set too thin, the heat sink fins 122 will become sharp and easily cause injuries to the user; at the same time, if the spacing between adjacent heat sink fins 122 is set too small, it is not easy to insert a cotton swab into the spacing for cleaning. If a cotton swab is forcibly inserted into the spacing for cleaning, the heat sink fins 122 may be easily damaged by the cotton swab due to the small thickness and weak strength of the heat sink fins 122. On the contrary, if the thickness of the heat sink fins 122 is too thick or the spacing is too large, the heat dissipation performance will be reduced. Therefore, it is necessary to set the thickness and spacing of the heat sink fins 122. After simulation experiments, the preferred scheme of the thickness and spacing of the heat sink fins 122 is finally confirmed: the thickness of the heat sink fins 122 is between 1-4mm, and the spacing of the heat sink fins 122 is between 2-4mm. The height of the heat sink fins 122 can be set according to the heat dissipation requirements.

[0037] In another embodiment, the radiator can also be directly formed on the motor housing, and the motor housing is formed by injection molding. Specifically, the motor housing includes a shell body that is integrally injection molded and a radiator formed on the shell body, that is, the radiator is a part of the motor housing. Specifically, the motor housing has an upper wall and a lower wall that are relatively arranged, and a front side wall, a rear side wall and a left side wall that are relatively arranged. An accommodating cavity is formed in the shell body by the upper wall, the lower wall, the front side wall, the rear side wall and the left side wall. The right side of the shell body is an opening. The radiator is formed on the upper wall. In this embodiment, since the radiator is directly formed on the upper wall and the upper wall is a part of the radiator, the outer surface of the radiator 12 is the outer surface of the upper wall, that is, a plurality of cooling fins are formed by extending upward from the outer surface of the upper wall.

[0038] As mentioned above, the motor 2 and the bearing chamber 4 are completely located in the housing 1. In the drive assembly 10, generally speaking, the radial dimension of the bearing chamber 4 will be larger than the radial dimension of the motor 2, so the side wall of the bearing chamber 4 may be in contact with the radiator 12. As described above, the heat generated by the motor 2 is greater than the heat generated by the bearing chamber 4, so the temperature of the air flow in the first air gap 61 will be greater than the temperature of the air flow in the second air gap 62. In order to further ensure the uniform distribution of the surface temperature of the radiator 12 and to prevent the side wall of the bearing chamber 2 from directly contacting the radiator 12, in one embodiment, in the axial direction parallel to the rotation axis xx, a fourth air gap 63 is formed between the end face of the bearing chamber 4 close to the motor 2 and the radiator 12, and the fourth air gap 63 is in fluid communication with the first air gap 61 and the second air gap 62, respectively. By setting the fourth air gap 63, air flows of different temperatures in different air gaps can form convection.

[0039] In an optional embodiment, the motor 2 and the bearing chamber 4 are at least partially fitted together or connected by a connection structure that can achieve heat conduction. In this way, a portion of the heat of the motor 2 is transferred to the bearing chamber 4 through heat conduction, and then conducted to the radiator 12 through the second air gap 62, and another portion of the heat is conducted to the radiator 12 through the first air gap 61, thereby effectively ensuring that the surface temperature of the radiator 12 is evenly distributed.

[0040] In this embodiment, the motor 2 is fixed in the motor housing 11 through the bearing chamber 4, and the motor 2 does not contact other parts of the motor housing 11. Specifically, the bearing chamber 4 is fixed to the motor housing 1, and the motor 2 is fixed on one end surface of the bearing chamber 4. A gap 7 is formed between the motor 2 and the motor housing 11 (the front side wall, the rear side wall, the left side wall 112 and the lower wall 111). Compared with the motor 2 being directly fitted with the motor housing 11, the gap 7 forms a heat-insulating space between the motor 2 and the motor housing 11, thereby preventing the heat generated by the motor 2 from being directly conducted through the front side wall, the rear side wall, the left side wall 112 and the lower wall 111, thereby preventing the front side wall, the rear side wall, the left side wall 112 and the lower wall 111 from being locally overheated. The gap 7 can also be called a vibration gap. Since the motor 2 is the main vibration source, the vibration gap is set to prevent the motor 2 from directly contacting the front side wall, the rear side wall, the left side wall 112 and the lower wall 111, which is beneficial to the overall vibration reduction of the drive assembly 10.

[0041] In one embodiment, the drive assembly 10 further includes a bearing chamber cover 8 for engaging with the catheter pump. The bearing chamber cover 8 is connected to an end face of the bearing chamber 4 away from the motor 2. The bearing chamber cover 8 covers at least a portion of the active component 3. The active component 3 generates heat while transmitting power, and a portion of the generated heat is transmitted outward through the bearing chamber cover. As mentioned above, the heat generated by the motor 2 is greater than the heat generated by the bearing chamber 4. Similarly, in this embodiment, the heat generated by the motor 2 is also greater than the heat generated by the bearing chamber cover 8. Therefore, in order to ensure uniform temperature distribution on the surface of the radiator 12, in the radial direction, the air gap between the motor 2 and the radiator 12 is set to be greater than the air gap between the bearing chamber cover 8 and the radiator 12. Specifically, in the radial direction, a third air gap 64 is formed between the surface of the bearing chamber cover 8 facing the radiator 12 and the radiator 12, and the first air gap 61 is greater than the third air gap 64.

[0042] In one embodiment, the radial dimension of the bearing chamber 4 will be larger than the radial dimension of the bearing chamber cover 8, and the side wall of the bearing chamber 4 may be in contact with the radiator 12. In order to further ensure that the surface temperature of the radiator 12 is evenly distributed, in the axial direction parallel to the rotation axis xx, a fifth air gap 65 is formed between the end surface of the bearing chamber 4 away from the motor 2 and the radiator 12, and the fifth air gap 65 is fluidly connected to the second air gap 62 and the third air gap 64, respectively.

[0043] Since the bearing chamber 4 is close to the motor 2, the heat of the bearing chamber 4 is greater than the heat of the bearing chamber cover 8, so the temperature of the airflow in the second air gap 62 is greater than the temperature of the airflow in the third air gap. By forming the fifth air gap 65, the second air gap 62 and the third air gap 64 can be connected, so that the relatively high temperature airflow in the second air gap 62 and the relatively low temperature airflow in the third air gap 64 form convection, so as to ensure that the surface temperature of the radiator 12 is evenly distributed.

[0044] Please combine Figure 1 and Figure 2 The embodiment of the utility model also provides a device for assisting the heart when functional failure occurs, which includes a drive assembly 10 and a catheter pump 20. The structure of the drive assembly 10 adopts the structure of the drive assembly 10 in the above example, which will not be described in detail here.

[0045] In an illustrative scenario, the catheter pump 20 can be used as a left ventricular assist, and its working part (specifically the pump head 23 below) can be inserted into the left ventricle. When the pump head 23 is in operation, it can pump the blood in the left ventricle into the ascending aorta.

[0046] It is worth noting that the above example of being used as a left ventricular assist is only one feasible application scenario of the catheter pump 20. In other feasible scenarios that cannot be explicitly excluded, the catheter pump 20 can also be used to assist the right ventricle, and the pump head 23 can be inserted into the right ventricle, and the pump head 23 pumps the blood in the vein to the right ventricle when it is in operation. Of course, the catheter pump 20 can also be used to assist the kidneys, as a renal pump.

[0047] The catheter pump 20 may adopt an existing structure, and the catheter pump 20 generally includes a catheter 21, a drive shaft 22 inserted in the catheter 21, and a pump head 23 connected to the distal end of the catheter 21. The pump head 23 includes a pump housing 231 having an inlet and an outlet, and an impeller 232 accommodated in the pump housing 231. The distal end (unnumbered) of the drive shaft 22 is connected to the impeller 232, and the proximal end (unnumbered) thereof is connected to a driven member 24, and the driven member 24 is detachably coupled to the driving member 3 to transmit the driving force of the motor 2 to the impeller 232, and the impeller 232 is driven to rotate, thereby sucking blood from the inlet into the pump housing 231 and discharging it from the outlet.

[0048] In one embodiment, the active member 3 and the driven member 24 adopt an eddy current coupling transmission mode, that is, one of the two is a magnetic force providing element and the other is a conductor, and a gap is formed between the two. The magnetic force providing element is a magnet with its own magnetism, such as a permanent magnet. The conductor can be made of metal, such as copper, aluminum, or an alloy containing copper and aluminum with good electrical conductivity. In this embodiment, the active member 3 has an outer rotor 31, and a conductor 32 is arranged inside the outer rotor 31 (see Figure 1 ). A permanent magnet is arranged in the driven member 24.

[0049] In other embodiments, the active member and the driven member may also be connected by magnetic coupling, that is, both the active member and the driven member are provided with permanent magnets, and the specific connection method is not described in detail here.

[0050] It should be understood that the above description is for illustration and not for limitation. By reading the above description, many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art. Therefore, the scope of this teaching should not be determined with reference to the above description, but should be determined with reference to the attached claims and the full scope of equivalents possessed by these claims.

Claims

1. A drive assembly, characterized in that: Used to drive the catheter pump to work, the driving component includes: a motor having an output shaft rotatable about a rotation axis; an active member connected to an output shaft of the motor to transmit a driving force of the motor; and A bearing chamber, used for rotatably supporting the active member; Wherein, at least part of the outer shell of the drive assembly is formed as a radiator, which covers at least a portion of the motor and at least a portion of the bearing chamber; in a radial direction perpendicular to the rotation axis, a first air gap is formed between the surface of the motor facing the radiator and the radiator, and in the radial direction, a second air gap is formed between the surface of the bearing chamber facing the radiator and the radiator, and the first air gap is larger than the second air gap.

2. The drive assembly according to claim 1, characterized in that: The drive assembly further comprises a bearing chamber cover for engaging with the catheter pump, the bearing chamber cover being connected to an end surface of the bearing chamber away from the motor, and the bearing chamber cover at least covers a portion of the active member; In the radial direction, a third air gap is formed between the surface of the bearing chamber cover facing the radiator and the radiator, and the first air gap is larger than the third air gap.

3. The drive assembly according to claim 1, characterized in that: In an axial direction parallel to the rotation axis, a fourth air gap is formed between an end surface of the bearing chamber close to the motor and the heat sink, and the fourth air gap is fluidically connected to the first air gap and the second air gap, respectively.

4. The drive assembly according to claim 2, characterized in that: In an axial direction parallel to the rotation axis, a fifth air gap is formed between an end surface of the bearing chamber away from the motor and the heat sink, and the fifth air gap is fluidically connected to the second air gap and the third air gap, respectively.

5. The drive assembly according to claim 1, characterized in that: The motor and the bearing housing are at least partially in contact with each other or connected via a connection structure that enables heat conduction.

6. The drive assembly according to claim 1, characterized in that: The motor is fixed to the housing of the drive assembly through the bearing chamber.

7. The drive assembly according to claim 1, characterized in that: The outer surface of the radiator is provided with a plurality of radiating fins.

8. The drive assembly according to claim 7, characterized in that: The thickness of the heat dissipation fins is between 1-4 mm.

9. The drive assembly according to claim 7 or 8, characterized in that: The distance between adjacent heat dissipation fins is between 2-4 mm.

10. A device for assisting a heart in the event of heart failure, characterized in that: comprising a drive assembly and a catheter pump as claimed in any one of claims 1 to 9; The catheter pump comprises: a catheter, a driving shaft passing through the catheter, and a pump head connected to the distal end of the catheter; The pump head comprises: a pump housing having an inlet and an outlet, and an impeller received in the pump housing; The distal end of the drive shaft is connected to the impeller, and the proximal end thereof is connected to a driven member, and the driven member is detachably coupled to the driving member to transmit the driving force of the motor to the impeller, and the impeller is driven to rotate, thereby sucking blood from the inlet into the pump housing and discharging it from the outlet.

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