JPH0363064A - Fluidtight rotational transmission apparatus - Google Patents

Abstract

PURPOSE:To prevent the application of excessive deformation stress on a diaphragm by prescribing the shaking motion of a coupling member through a parallel crank mechanism. CONSTITUTION:The crank shaft constituting a parallel crank mechanism is arranged between the rear surface of the first coupling part 18 and the bottom part 12a of a motor holder 12. This crank shaft is constituted of a restriction shaft 21 and, since the longitudinal direction of the eccentric quantity (e) of the eccentric axis 24 of the restriction shaft 21 and that of the eccentric quantity (e) of the eccentric axis 16 of an eccentric adaptor 15 are parallel, when the eccentric adaptor 15 is rotated with the rotation of a motor shaft 14, the first coupling part 18 performs prescribed shaking motion along a definite plane so as to respectively hold parallel relation at any position. Therefore, the diaphragm 30 provided between the second coupling part 19 and a housing 1 under tension receives only the deformation load based on the prescribed shaking motion of the coupling member but no other load at all.

Description

[Detailed Description of the Invention] [Industrial Application Field J] The present invention transmits rotation from a drive source outside the housing to a rotating body such as an impeller disposed in a fluid-tight housing such as a blood pump. This invention relates to a fluid-tight rotation transmission device used for.

[Prior Art 1] As this type of fluid-tight rotation transmission device, one that transmits rotation via an elastically deformable diaphragm for sealing, for example, is known. A fluid-tight rotation transmission device having this diaphragm completely seals the housing with a deformable diaphragm such as a diaphragm, and transmits rotation from a drive source outside the housing to a rotating body inside the housing through allowable deformation of the diaphragm. It is now possible to do so. Therefore, if this is used in, for example, a blood pump, even if blood inside the housing leaks for some reason from a bearing that supports a rotating body with respect to the housing, the leaked blood will be used to drive the outside of the housing. The fear of leakage to the source and eventual blood contamination is eliminated.

As a conventional fluid-tight rotation transmission device of this type,
In the configuration shown in No. 267458, a driven rotating shaft of a rotating body such as an impeller in the housing and a driving rotating shaft of a drive source outside the housing are each provided with a crank part capable of crank movement, and both crank parts are connected to each other. The housing is connected to the crank portion by a relatively rotatable coupling member, and a diaphragm is provided between the coupling member and the housing to close the housing in a fluid-tight manner. According to this configuration, when the coupling member moves due to the crank movement of the crank part on the drive rotation shaft side, the diaphragm deforms accordingly, and the resistance force accompanying the deformation prevents the deformation from expanding. 5. The coupling member is rotated relative to the crank portion in the direction shown in FIG. Therefore, the coupling member maintains the deformation within the permissible limit so as not to twist the diaphragm, performs a rocking motion regulated by the resistance force, and moves from the crank part on the driving rotating shaft side to the driven rotating shaft side. The crank motion is transmitted to the crank unit, and as a result, the rotating body within the housing can rotate.

[Problems to be Solved by the Invention] By the way, in the conventional fluid-tight rotation transmission device using a diaphragm, the rocking motion of the coupling member that transmits crank motion is restricted by the resistance force of the diaphragm itself. However, extra deformation stress is applied to the diaphragm, and unless special consideration is given to the deformation strength of the diaphragm, sufficient durability cannot be obtained, which is a problem.

In particular, if the fluid-tight rotation transmission device described above is used in devices that require continuous operation without interruption, such as blood pumps, the diaphragm is likely to break early due to fatigue due to repeated stress during operation. As a result, there have been problems involving risks such as leakage of blood within the housing and blood contamination.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to regulate the rocking motion of a coupling member that transmits crank motion without relying on the resistance force of the diaphragm itself. To provide a fluid-tight rotational transmission device in which deformation stress is not applied and sufficient durability can be obtained without special consideration of deformation strength of a diaphragm.

[Means for Solving the Problems] In order to solve the above conventional problems, in the present invention,
A device main body, a housing provided on the device main body so as to allow fluid to circulate therein, a rotating body disposed within the housing, a rotating driven shaft attached to the rotating body, and a rotating driven shaft disposed outside the housing. a rotary drive shaft rotatable by a drive source provided therein; first and second crank portions provided on opposite sides of the rotary drive shaft and the rotary driven shaft and capable of crank movement; The coupling member is connected to each of the second crank parts and is movable in a swinging manner so as to transmit crank motion from the first crank part to the second crank part. A crank transmission means for transmitting transmission to a rotation driven shaft, and a coupling member of the crank transmission means and the housing, which is stretched between the housing and fluid-tightly closes the housing and allows the crank movement of the crank transmission means. The present invention proposes a fluid-tight rotation transmission device comprising a deformable diaphragm as described above, characterized in that the rocking motion of the coupling member is regulated via a parallel crank mechanism.

In the above configuration, the parallel crank mechanism specifically includes a crankshaft that is disposed between the coupling member and the main body of the device via a bearing and that is parallel to the axis of the rotational drive shaft. It is proposed as a general structure.

As a more specific configuration, it is proposed that the parallel crank mechanism is a three-crank parallel motion mechanism consisting of three crank shafts arranged in an equal relationship around the rotational drive shaft.

Further, in each of the above configurations, the coupling member is
The first coupling part is connected to the first crank part via a bearing, and the second coupling part is connected to the second crank part via a bearing. A specific structure is proposed in which the coupling portion is separably engaged with the rotary drive shaft and the rotary driven shaft in the axial direction.

Furthermore, in each of the above configurations, a specific example is one in which a blood inlet and an outlet are formed in the housing, and blood flows in from the inlet and flows out from the outlet according to the rotation of the rotating body. proposed as a configuration.

[Function] According to the fluid-tight rotation transmission device according to the present invention having the above configuration,
The coupling member, which is capable of swinging motion so as to transmit crank motion from the first crank section to the second crank section, has its swing motion regulated via the parallel crank mechanism, so that it remains in a fixed plane. No matter where you are along the line,
The diaphragm, which is stretched between the coupling member and the housing, receives only the deformation load based on the pre-regulated rocking movement of the coupling member. The diaphragm is not subjected to any other load, and therefore the service life of the diaphragm can be improved.

[Embodiment] Hereinafter, an embodiment of a fluid-tight rotation transmission device of the present invention used in a blood pump will be described with reference to FIGS. 1 and 2.

In the figure, 1 is a housing. This housing l is composed of a pump case 2 and a pump base 3. The pump case 2 is formed into a substantially conical shape, and the bottom thereof is closed with a pump base 3. A blood inlet 4 is formed at the upper end of the pump case 2, and a blood outlet 5 is formed in the tangential direction at the circumferential side.

The pump base 3 has an upper end closed with a flange 3a, and is integrally formed into a substantially short cylindrical shape.

The peripheral edge of the flange 3a is fluid-tightly fixed to the lower end peripheral edge of the pump case 2 by screws (not shown), and a thick impeller shaft support part 3b is formed in the center thereof.

An impeller 6 serving as a rotating body is provided inside the housing 1 configured in this manner.

As the impeller 6 rotates, blood flows into the housing l from the blood inlet 4 as shown by the arrow in FIG.
The blood is allowed to circulate and flow out from the blood outflow port 5.

The lower part of the impeller 6 has an axis 7 in the vertical direction,
An impeller shaft 8 constituting a rotation driven body is integrally attached. The impeller shaft 8 is rotatably supported by the impeller shaft support part 3b of the pump base 3 via a bearing 9 so as to pass through the impeller shaft support part 3b. This bearing 9
On the upper side, a V-ring 10.10 and its counter face 1) are installed between the support part 3b and the impeller shaft 8. This prevents the bearing 9 from coming into direct contact with blood, resulting in a structure that takes hygiene into consideration. Note that a sealing member such as a lip seal can also be used instead of the ring 10.

On the other hand, on the lower side of the housing 1, a motor holder 12 that constitutes the main body of the device is arranged. This motor holder 1
2 has a bottom portion 12a integrally and is formed into a short cylindrical shape. An enlarged diameter part 12b is formed on the inner circumferential surface of the upper end of the holder 12, and the lower end of the pump base 3 is fitted into this enlarged diameter part 12b and is restricted from coming into contact with the motor holder 12. , the housing 1 is removable in the direction of the axis 7 and can be mounted in a predetermined position. At this time, in the female screw hole formed in the radial direction of the enlarged diameter portion 12b,
By screwing a screw (not shown) from the outside and tightening it to the lower end of the pump base 3, the housing 1
Escape is prevented.

A drive motor 3 constituting a drive source is attached to the bottom surface of the motor holder 12. This drive motor 13
has a motor shaft 14 facing upward, which constitutes a rotational drive shaft. The motor shaft 14 passes through the bottom 12a of the holder 12 and faces into the holder 12, so that the axial center of the motor shaft 14 is located on the axial center 7 of the impeller shaft 8.

A crank transmission means for transmitting the rotation of the motor shaft 14 to the impeller shaft 8 is provided between the motor shaft 14 and the impeller shaft 8 . This crank transmission means has a first
It is composed of a crank part, a second crank part, and a coupling member.

The first crank portion includes an eccentric adapter 15, which is fitted and fixed to the motor shaft 14. The eccentric adapter 15 has an eccentric shaft center 16 that is eccentric by an eccentric amount e with respect to the shaft centers 7 of the motor shaft 14 and the impeller shaft 8, and is formed in a cylindrical shape.

Thereby, the eccentric adapter 15 can be cranked relative to the rotation of the motor shaft 14.

The second crank portion is composed of an eccentric joint 17 and is fitted and fixed to the lower end portion of the impeller shaft 8. The eccentric joint 17 is configured such that an eccentric shaft 17a having an eccentric shaft center located on the eccentric shaft center 16 of the eccentric adapter 15 is integrally provided at the lower part thereof. As a result, the impeller shaft 8
The eccentric joint 17 is capable of crank movement with respect to the rotation of.

The coupling member includes a first coupling part 18 and a second coupling part 18.
The coupling portion 19 is comprised of a coupling portion 19 .

The first coupling part 18 is connected to the eccentric adapter 15. The first coupling portion 18 has a lower portion formed into a disk shape, and an internal gear 18a integrally formed on the upper portion thereof. A bearing 20 is mounted at the center of the lower surface of the first coupling part 18, and the eccentric adapter 15 is rotatably supported by the bearing 20.

The internal gear 18a on the upper part of the first coupling part 18 has its axis aligned with the eccentric axis 16.

A crankshaft forming a parallel crank mechanism is disposed between the lower surface of the first coupling portion 18 and the bottom portion 12a of the motor holder 12.

The crankshaft is constituted by a restraint shaft 21, the lower end of which is rotatably supported by a bearing 22 on the upper surface of the bottom 12a of the motor holder 12. The axis 23 of this lower end
are parallel to the axis 7. restraint shaft 21
The upper end portion is formed to have an eccentric shaft center 24 that is eccentric with respect to the shaft center 23 of the lower end portion by an eccentric amount e that is the same as the eccentric amount e, and is connected to the first coupling member via a bearing 25. It is rotatably supported on the lower surface of 18. At this time, the length direction of the eccentric amount e of the eccentric shaft center 24 of the restraining shaft 21 and the length direction of the eccentric amount e of the eccentric shaft center 16 of the eccentric adapter 15 are parallel to each other. As a result, the restraint shaft 21
and the eccentric adapter 15 act as a crank of the parallel motion mechanism. Therefore, when the eccentric adapter 15 rotates as the motor shaft 14 rotates, the first coupling portions 18 maintain a parallel relationship at any position along a fixed plane. It is designed to perform a regulated rocking motion.

As shown in FIG. 2, three restraining shafts 21 are arranged evenly around the axis 7 of the motor shaft 14, and these three restraining shafts 21 form a three-crank parallel motion mechanism. Can be configured. According to this three-crank parallel motion mechanism, the first coupling portion 18 can swing smoothly, and furthermore, by uniformly disposing the restraint shafts 21, smooth rocking motion can be obtained.

At this time, the parallel crank mechanism can be constructed by using a gear or a belt instead of the crankshaft constituted by the restraining shaft 21.

In FIG. 2, the eccentric adapter 15, the restraining shaft 21, and the first coupling portion 18 shown by the two-dot chain line are connected to the motor shaft 14.
It shows the respective states when it rotates 180 times.

The second coupling portion 19 is connected to the eccentric joint 17 via a bearing 26. This second coupling portion 19 includes a pair of split members 19a, 19b and an external gear 19c.
It is composed of. Of the split members 19a and 19b,
One split member 19a is formed into an annular shape, and the other split member 19b is formed into a container shape integrally having a stepped bottom. Both split members 19a and 19b are one split member 1
They are mated and fixed with the split member 9a facing up and the other split member 19b facing down, thereby holding the bearing 26 on their inner circumferential surfaces. The eccentric shaft 17a of the eccentric joint 17 is rotatably supported by the bearing 26. A nut 27 is screwed and tightened to the lower end of the eccentric shaft 17a to prevent the eccentric shaft 17a from slipping out of the bearing 26.

The split members 19a and 19b are matched and fixed by forming a female thread in the upper split member 19a at their peripheral edges, and screwing and tightening the flat screw 28 into the female thread. At this time, the lower surface of the head of the ribs 28 is made to be flush with the lower surface of the split member 19b located below.

A male threaded portion 29 is integrally protruded from the lower surface of the split member 19b located below the eccentric shaft 16, and the external gear 19C is screwed and fixed to the male threaded portion 29&. This external gear 19c is formed in a concave shape and follows the shape of the lower surface of the split member 19b. Further, the external gear 19c has its axis coincident with the eccentric axis 16, and is engaged with the internal gear 29 so as not to rotate relative to each other. The force and the Sopring portion 19 can be separated along the eccentric axis 16 to 7 directions of the axis.

Due to this engagement, the second coupling part 19 is integrated with the first coupling part 18 and performs a regulated rocking movement, so that the second coupling part 19 moves through the bearing 26. In contrast, the eccentric shaft 17a of the eccentric joint 17 rotates, and the eccentric joint 17 performs a crank motion, and as a result,
Crank motion can be transmitted from the eccentric adapter 15 to the eccentric joint 17.

Therefore, in the above-mentioned parallel crank mechanism, the first coupling part 18 is arranged so as to restrict its swinging motion, but the second coupling part 19 is arranged so as to restrict its swinging motion. Even if a parallel crank mechanism is provided so as to restrict the
The coupling member constituted by 9 is capable of obtaining the necessary rocking motion.

Further, the separation and engagement of the first and second coupling portions 18°i9 is not limited to the internal gear 18a and external gear 19c, and may be performed using other gears such as splines.

The split member L9 that constitutes the second coupling portion 19
A deformable diaphragm 30 is stretched between the outer circumferential surfaces of the impeller shafts a and 19b and the outer circumferential surface of the impeller shaft support portion 3b of the pump base 3 constituting the housing l. As a result, even if the sealing effect is reduced due to blood coagulation around the V-ring 10 and blood leaks to the bearing 9 side, the diaphragm 30 blocks the blood and prevents it from leaking outside. Good fluid tightness within 1.

The diaphragm 30 is formed of a deformable diaphragm, for example, as shown in the figure, or other bellows including a metal bellows, thereby restricting the oscillation of the coupling member, as shown by the two-dot chain line in FIG. It is designed to be able to follow the dynamic movement, that is, to allow the crank movement performed by the crank transmission means. or,
The diaphragm 30 can be attached by physical fixation such as adhesion, high frequency welding, and screw tightening.

According to the fluid-tight rotation transmission device having the above configuration, when the coupling member moves along a certain plane in accordance with the crank motion of the first crank portion 18, the coupling member is at any position on the plane of movement. However, the second coupling portion 1 swings to maintain a parallel relationship.
The diaphragm 30 stretched between the diaphragm 9 and the housing 1 receives only the deformation load based on the pre-regulated rocking movement of the coupling member, and is not subjected to any other load, resulting in a strong For example, sufficient durability can be obtained even with a normal thin diaphragm without any special considerations. This improved durability prevents damage to the diaphragm 30 during operation even when continuous operation is required, such as in medical equipment such as blood pumps, and prevents blood from leaking inside the housing and blood contamination. You can eliminate fear.

Also, by removing the housing 1 from the motor holder 12 and separating the device between the first coupling part 18 and the second coupling part 19, the housing l including the blood contact part can be discarded. Blood contamination, etc. can be prevented, and other parts, such as the motor holder 12, can be reused.

Although the present invention has been described above with reference to Examples, the present invention is not limited to the above-mentioned Examples, and can be modified in various ways without changing the gist of the present invention. For example, in the embodiment, a fluid-tight rotation transmission device used in a blood pump has been described, but the invention is not limited to this.
It is also applicable to fluids other than blood, and even centrifuges and the like.

[Effects of the Invention] As explained above, according to the fluid-tight rotation transmission device according to the present invention, since the rocking motion of the coupling member is regulated via the parallel crank mechanism, the coupling member can At any position along a certain plane,
The diaphragm is oscillated to maintain a parallel relationship and is therefore stretched between the coupling member and the housing.
It receives only the deformation load based on the pre-regulated rocking motion of the coupling member, and does not receive any other load, and even with a normal thin-walled diaphragm, it can maintain durability for long-term use. , it can be suitably used without danger in the field of medical equipment such as blood pumps.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional front view showing an embodiment of the fluid-tight rotation transmission device of the present invention used in a blood pump;
The figure is a sectional view taken along the line A--A in FIG. 1. l...Housing, 4...Blood inlet 5
... Blood outflow port, 7 ... Motor shaft and a8 ... Impeller shaft, 13 ... Drive motor, 15 ... Eccentric adapter, 18 ... First coupling 19 ... Second Coupling 20...Bearing, 22, 25...Bearing, 30...Diaphragm 6...Axis center of impeller shaft 12...Motor holder 14...Motor shaft 17...Eccentric coupling part Ring part 21...Restriction shaft 26...Bearing

Claims (4)

[Claims] (1) A device main body, a housing provided in the device main body so as to allow fluid to circulate therein, a rotating body disposed within the housing, a rotating driven shaft attached to the rotating body, and the housing. a rotary drive shaft rotatable by a drive source disposed outside; first and second crank portions each provided on opposing sides of the rotary drive shaft and the rotary driven shaft and capable of crank movement; 1st and 2nd
The coupling member is connected to each of the crank parts and is movable in a swinging manner so as to transmit crank motion from the first crank part to the second crank part. A crank transmission means for transmitting transmission to the shaft, a coupling member of the crank transmission means and the housing, and is stretched between the crank transmission means and the housing, so as to close the housing in a fluid-tight manner and to allow crank operation of the crank transmission means. 1. A fluid-tight rotation transmission device comprising a deformable diaphragm, characterized in that the rocking motion of the coupling member is regulated via a parallel crank mechanism. (2) The parallel crank mechanism includes a crankshaft that is disposed between the coupling member and the device main body via a bearing and is parallel to the axis of the rotational drive shaft. Fluid-tight rotation transmission device. (3) The fluid-tight rotation transmission device according to claim 2, wherein the parallel crank mechanism is a three-crank parallel motion mechanism consisting of three crank shafts arranged in an equal relationship around the rotational drive shaft. . (4) The coupling member includes a first coupling part connected to the first crank part via a bearing and a second coupling part connected to the second crank part via a bearing. The fluid-tight rotational transmission according to any one of claims 1 to 3, wherein the first and second coupling portions are separably engaged in the axial direction of the rotational driving shaft and the rotational driven shaft. Device. (5) The fluid tightness according to any of claims 1 to 4, wherein a blood inlet and an outlet are formed in the housing, and blood is caused to flow in from the inlet and to flow out from the outlet according to the rotation of the rotating body. Rotation transmission device.