JP6747716B2 - Ball joint and arm device - Google Patents

Description

The present invention relates to a ball joint and an arm device including the ball joint.

In the medical field, for example, arm devices hold medical instruments during surgery. In this case, it is required that the arm device and the medical instrument can be freely moved and fixed when necessary. As a technique of this kind, for example, Patent Document 1 discloses a telescopic holding arm device for medical instruments.

JP2012-95679A

Patent Document 1 discloses a configuration for switching lock/free at a plurality of locations such as a ball joint by an air clutch system.
However, when the air clutch system is adopted, it is necessary to install the air clutch and the surrounding structure (air flow path, air source, etc.), which complicates the configuration and increases the size.

Here, in some cases, it is preferable that the ball joint has a structure in which rotation of the ball in a predetermined direction is restricted rather than giving directionality to the movement of the ball, in other words, making the ball freely rotatable in all directions. For example, when adopting a structure for switching lock/free of the ball joint, it is conceivable that lock/free can be surely switched by adopting a structure that gives direction to the movement of the ball even when it is free. ..

The present invention has been made in view of the above points, and an object thereof is to provide directionality to the movement of a ball in a ball joint.

In order to solve the above problems, the gist of the present invention is as follows.
[1] Ball,
A through hole is formed, and a frame member in which the ball is arranged inside the through hole,
The ball is configured to restrict rotation around an axis extending in the one radial direction ,
A ball joint , wherein an insertion hole for inserting a rod-shaped body is formed in the ball, and the ball joint functions as a holding device for the rod-shaped body .
[2] The inner peripheral surface of the through hole has a maximum diameter at the center between the opening edges at both ends thereof, and has a concave arc surface that reduces in diameter toward each of the opening edges [1] Ball joint described in.
[3] A locking surface portion is provided on a part of the inner peripheral surface of the through hole, and at the position where the locking surface portion is provided, the inner peripheral surface of the through hole should not be the concave arc surface. The ball joint according to [2], which restricts rotation of the ball around the axis.
[4] A chamfered portion is formed in a strip shape on the outer peripheral surface of the ball so as to pass through the openings at both ends of the insertion hole and along the entire circumference of the ball, and the chamfered portion faces the locking surface portion. the ball joint according to [3], wherein the chamfered portion is characterized that you have been so as not to interfere with the locking surface when moving the ball.
[ 5 ] The ball is divided by a dividing line passing through openings at both ends of the insertion hole,
The ball is fixed by contacting the ball with an abutting member that can move in and out from the radial direction of the through hole inward of the through hole, and the rod-shaped body that is inserted through the insertion hole is also fixed. The ball joint according to any one of [1] to [4] .
[ 6 ] The ball joint according to [ 5 ], wherein the dividing line of the ball is arranged so as to be displaced from the position where the contact member moves in and out.
[ 7 ] The ball joint according to any one of [1] to [6], wherein the axis is an axis of the insertion hole.
[ 8 ] The ball joint according to [ 5 ] or [ 6 ],
The ball joint is provided with an arm provided at the tip,
The arm device is characterized in that the arm is provided with a projecting member that moves in and out from the tip by a predetermined operation, and the projecting member projects the abutting member into contact with the ball.

According to the present invention, it is possible to give directionality to the movement of the ball in the ball joint.

It is a perspective view showing an arm device concerning an embodiment. It is a figure for demonstrating the ball of a holding device of a ball joint type. It is a figure for demonstrating the frame member of a holding device of a ball joint type. It is a figure for demonstrating a holding device of a ball joint type. It is a figure for demonstrating a holding device of a ball joint type. It is a figure for explaining an arm. It is a figure for explaining an arm. It is a figure for demonstrating a base. It is a figure for demonstrating a base.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the following, if necessary, front-back, left-right, and up-down directions are shown in the drawings, and the directions will be used for description.
As shown in FIG. 1, the arm device according to the present embodiment includes a base 3 supported by a support rod 4, an arm 2 supported by the base 3, and a ball joint type holding device provided at the tip of the arm 2. 1 and 1. The ball joint type holding device 1 includes a ball 5 in which an insertion hole 6 is formed, and a rod-shaped medical device 7, for example, a cannula or a rigid endoscope can be inserted and held in the insertion hole 6. .. This ball joint type holding device 1 is an example of a ball joint to which the present invention is applied.

First, the ball joint type holding device 1 will be described with reference to FIGS. 2 to 5.
The ball joint type holding device 1 includes a ball 5 having an insertion hole 6 and a frame member 8.

2A and 2B are views for explaining the ball 5, where FIG. 2A is a perspective view of the ball 5, FIG. 2B is a front view of the ball 5, FIG. 2C is a side view of the ball 5, and FIG. And (e) is a perspective view of the hemisphere 5a.
As shown in FIG. 2, the ball 5 is divided into two by a dividing line 9 passing through the openings 6a and 6b at both ends of the insertion hole 6, and is constituted by a pair of hemispheres 5a. As shown in FIG. 2(e), a groove 10 is formed on the divided surface of the hemisphere 5a along the circumferential direction of the insertion hole 6, and a pair of hemispheres is inserted by a ring (not shown) inserted into the groove 10. 5a is positioned.

On the outer peripheral surface of the ball 5, chamfered portions 11 are formed on both sides so as to connect the openings 6a and 6b at both ends of the insertion hole 6. The chamfered portion 11 is formed in a flat and band shape so as to pass through the openings 6 a and 6 b at both ends of the insertion hole 6 and to extend along the entire circumference of the ball 5. The chamfered portion 11 is formed at a position overlapping the dividing line 9, and the dividing line 9 is located at the center of the chamfered portion 11 in the width direction. The distance a in the normal direction between the chamfered portions 11 on both sides is smaller than the diameter b of the ball 5 itself.
A protrusion 12 is formed around the opening 6a at one end of the insertion hole 6. Details of the protrusion 12 will be described later.

3A and 3B are views for explaining the frame member 8, where FIG. 3A is a perspective view of the frame member 8, FIG. 3B is a top view of the frame member 8, and FIG. 3C is a sectional view taken along line II of FIG. (D) is the II-II sectional view taken on the line of (b).
As shown in FIG. 3, the frame member 8 includes a ring portion 13 having a through hole 15 formed therein and a tubular portion 14 provided in a part of the ring portion 13, and the ball 5 is provided inside the through hole 15. Will be placed.
As shown in FIG. 3D, the inner peripheral surface 15c of the through hole 15 has a maximum diameter B at the center between the opening edges 15a and 15b at both ends thereof, and the diameter decreases toward the opening edges 15a and 15b. Then, each opening edge 15a, 15b forms a concave arc surface having a minimum diameter A.
The maximum diameter B and the minimum diameter A of the through hole 15 are set according to the diameter b of the ball 5. Specifically, the maximum diameter B is slightly larger than the diameter b of the ball 5, and the minimum diameter A is smaller than the diameter b of the ball 5, so that the ball 5 does not fall out.
The minimum diameter A of the through hole 15 is approximately the same as or slightly larger than the distance a between the chamfered portions 11 of the ball 5.

In the inner peripheral surface 15c of the through hole 15, a pair of locking surface portions 16 are provided at positions shifted in phase by 90 degrees with respect to the axis line of the tubular portion 14, in other words, the axis line C ₁ of the rod member 17 described later. Has been. The locking surface portion 16 has a planar circular shape that connects the opening edges 15 a and 15 b at both ends of the through hole 15. As a result, as shown in FIG. 3C, at the position where the locking surface portion 16 is provided, the inner peripheral surface 15c of the through hole 15 is not a concave arc surface, and the distance between the pair of locking surface portions 16 is It is about the same as the minimum diameter A of the through hole 15. The locking surface portion 16 may be configured by providing a member on the inner peripheral surface 15c as in the present embodiment (see FIG. 3C), or integrally with the inner peripheral surface 15c. It may be configured by being formed.

A cylindrical rod member 17 is movably inserted into the cylindrical portion 14, and the rod member 17 can be inserted and withdrawn in the inward direction of the through hole 15 from one radial direction of the through hole 15. At the position where the rod member 17 comes in and out, a notch 18 is formed on the inner peripheral surface 15c side of the ring portion 13, and the rod member 17 thicker than the thickness of the ring portion 13 comes in and out. The tip end surface of the rod member 17 is formed in an arc surface shape so as to fit the ball 5.

In the ball joint type holding device 1 configured as described above, the balls 5 are arranged such that the openings 6a and 6b of the insertion holes 6 are located vertically in FIG. That is, as shown in FIG. 4, with respect to the ring portion 13 of the frame member 8, one of the openings 6a and 6b of the insertion hole 6 is located in one of the thickness directions (vertical direction in FIG. 1) of the ring portion 13. On the other hand, the ball 5 is arranged so that the other of the openings 6a and 6b of the insertion hole 6 is positioned.
At this time, the chamfered portion 11 of the ball 5 is arranged so as to face the locking surface portion 16. That is, the dividing line 9 of the ball 5 is arranged so as to be displaced from the position where the rod member 17 moves in and out.

The diameter of the rod-shaped medical device 7 is slightly larger than the diameter of the insertion hole 6. Thereby, the medical instrument 7 is inserted into the insertion hole 6 in a state where the pair of hemispheres 5a are slightly separated from each other in the through hole 15. Therefore, the medical device 7 can be moved or rotated in the insertion hole 6 in the axial direction.

Here, in the free state, as shown in FIGS. 4 and 5, the ball 5 can be moved within the through hole 15 so as to tilt the axis C ₂ of the insertion hole 6 in any direction of 360 degrees. That is, similarly to a general ball joint, when the axis C ₂ of the insertion hole 6 is tilted in any direction of 360 degrees, the outer peripheral surface (the portion having the diameter b) of the ball 5 interferes with the inner peripheral surface 15c of the through hole 15. There is no such thing. Further, since the chamfered portion 11 faces the locking surface portion 16 and the distance A between the pair of locking surface portions 16 is the same as or slightly larger than the distance a between the chamfered portions 11, the axis C _{2 of the} insertion hole 6 The chamfered portion 11 does not interfere with the locking surface portion 16 when the is tilted in any direction of 360 degrees. In this way, the ball 5 can be moved so that the axis C ₂ of the insertion hole 6 is tilted in any direction of 360 degrees, so that the inclination of the medical device 7 can be freely changed.

However, the rotation of the ball 5 around the axis C ₂ of the insertion hole 6 is restricted as shown by the arrow with a cross mark in FIG. This is because, when the ball 5 tries to rotate about the axis C ₂ , the outer peripheral surface (portion having the diameter b) of the ball 5 interferes with the locking surface portion 16.

When the rod member 17 is brought into contact with the ball 5 from this free state, it can be switched to the locked state. When the rod member 17 is brought into contact with the ball 5, the ball 5 is pressed against the inner peripheral surface 15c of the through hole 15, so that the ball 5 can be fixed to the frame member 8. In addition, since the pair of hemispheres 5a come close to each other and are pressed against the medical device 7, the medical device 7 can be fixed to the ball 5.

When switching to the locked state, as described above, the ball 5 is configured to restrict rotation around the axis C ₂ of the insertion hole 6, so that the medical device 7 can be reliably fixed. For example, when the ball 5 can freely rotate around the axis C ₂ of the insertion hole 6, there may be a state in which the dividing line 9 of the ball 5 just faces the tip of the rod member 17. In this state, even if the rod member 17 is brought into contact with the ball 5, the pair of hemispheres 5a cannot be brought close to each other, and the medical device 7 cannot be fixed. On the other hand, by restricting the rotation of the ball 5 around the axis C ₂ of the insertion hole 6, the dividing line 9 of the ball 5 is displaced 90 degrees from the axis C ₁ of the rod member 17. Since the rod member 17 is kept in contact with the ball 5, the pair of hemispheres 5a can be surely brought close to each other. With such a configuration that gives direction to the movement of the ball 5, lock/free can be surely switched.

From the relationship between the minimum diameter A of the through hole 15 and the distance a between the chamfered portions 11, the entire region of the chamfered portion 11 of the ball 5 faces the inner peripheral surface 15c of the through hole 15, in other words, the insertion hole 6 When the axis C ₂ is aligned with the axis C ₁ of the rod member 17, the ball 5 can be pulled out from the through hole 15.
In this embodiment, the rod member 17 is brought into contact with the ball 5 by a spring or the like (not shown). The term "contact" as used herein means that the rod member 17 is brought into light contact with the ball 5 to the extent that the movement of the ball 5 and the medical device 7 is not disturbed in the free state. When the axis C ₂ of the insertion hole 6 is aligned with the axis C ₁ of the rod member 17, the protrusion 12 around the opening 6a of the insertion hole 6 is located in the notch 18, but at this time the protrusion 12 is the rod member. Since it interferes with 17, it is possible to prevent the ball 5 from coming off. In other words, when the ball 5 is pulled out from the through hole 15, the projection 12 is positioned in the notch 18 through the operation of pushing the rod member 17 against the spring or the like.

In the present embodiment, the chamfered portion 11 and the locking surface portion 16 have been described as flat surfaces, but it is sufficient that the chamfered portion 11 and the locking surface portion 16 do not interfere with each other. It does not matter if one of them has a concave substantially flat surface and the other has a convex substantially flat surface.

Next, the arm 2 will be described with reference to FIGS. 6 and 7.
FIG. 6 is an exploded perspective view of the arm 2. 7A and 7B are diagrams for explaining the movement of the arm 2, where FIG. 7A is a state where the width is not widened, and FIG. 7B is a diagram where the width is widened.
The arm 2 includes a rod 21, a pair of engagement bars 22L and 22R arranged on the left and right of the rod 21, and an arm body 23 that houses the rod 21 and the pair of engagement bars 22L and 22R so as to sandwich the rod 21 from above and below. The arm member 23 is provided with an operation member 24 that is connected to the front portion of the arm body 23. As shown in FIG. 1, by inserting the arm main body 23 into the insertion hole portion 44 of the base 3, the arm 2 is supported so as to be slidable forward and backward.

The rod 21 is provided with a screw portion 25 in a region excluding the tip portion thereof.

The pair of engagement bars 22L and 22R have teeth 26 formed on the inner side surface (the surface facing the screw portion 25) of which peaks and valleys are repeated. Further, plate surface portions 27 which are vertically overlapped with each other are formed at the rear end portions of the pair of engagement bars 22L and 22R, and the plate surface portion 27 is formed with a long hole 28 extending in the left-right direction.

The arm body 23 has a flat shape such as an ellipse that is thick in the center and thin in the left and right in the cross section, and the threaded portion 25 of the rod 21 is housed in the center thereof. Further, openings 29 opening in a slit shape are formed in the left and right and the rear end of the arm body 23, and the pair of engagement bars 22L and 22R are accommodated in the openings 29. As a result, the outer side surfaces of the pair of engagement bars 22L and 22R form the left and right side surfaces of the arm body 23. A pin 30 that is inserted into the elongated holes 28 of the pair of engagement bars 22L and 22R is fixed to the rear end of the arm body 23.

Similar to the arm body 23, the operation member 24 has a flat shape such as an ellipse that is thick in the center and thin in the left and right in the cross section, and the tip portion of the rod 21 is housed in the center portion. The operation member 24 allows the rod 21 to move back and forth (moves in the axial direction), but is integrally assembled with respect to the rotation of the rod 21 about its axis, and is rotated about the axis of the rod 21. That is, it can be operated so as to be twisted with respect to the arm body 23. A hole 31 is formed in the tip surface of the operation member 24 so that the tip portion of the rod 21 can be projected. The ball joint type holding device 1 is provided at the tip of the operation member 24, and the tip of the rod 21 abuts the rod member 17.

In the arm 2 configured as above, when the operation member 24 is operated to be twisted with respect to the arm body 23, the rod 21 is moved by the engagement of the screw portion 25 of the rod 21 and the teeth 26 of the pair of engagement bars 22L and 22R. Advance. As a result, the rod member 17 is pushed by the tip of the rod 21 and abuts on the ball 5, and the ball 5 and the medical device 7 held by the ball 5 are locked as described above.

If the operating member 24 is further twisted from this state, the rod 21 cannot move any further, and therefore the threaded portion 25 of the rod 21 and the teeth 26 of the pair of engaging bars 22L and 22R mesh with each other so that the pair of engaging members engage. The joining bars 22L and 22R move outward along the elongated hole 28 and the pin 30, respectively. That is, as shown in FIG. 7B, the arm body 23 is widened. By expanding the width of the arm body 23 in this manner, the arm body 23 is stretched in the insertion hole portion 44 of the base 3, and the arm 2 can be fixed to the base 3.

Next, the base 3 will be described with reference to FIGS. 8 and 9.
FIG. 8 is an exploded perspective view of the base 3. Further, FIG. 9 is a diagram for explaining the movement of the base 3, (a) is a side view of the base 3 (a view of an arrow IX in FIG. 8), and (b) and (c) are (a). FIG. 3 is a sectional view taken along line III-III of FIG.
The base 3 includes a base main body 33 supported by the support rod 4, a first support member 34, a second support member 35, and a pair of lock members 36, 36.

The base body 33 is formed with a hole 37 through which the support rod 4 is inserted, and an insertion hole 38 that is arranged at a position where the hole 37 is twisted. A part of the support rod 4 inserted through the hole 37 is an insertion hole. Exposed at 38.

The first support member 34 includes an insertion portion 39 that is inserted into the insertion hole 38 of the base body 33, and a flange 40 that is provided at the base end of the insertion portion 39. The insertion portion 39 has a diameter-expanded portion 41 on the front end side and a diameter-reduced portion 42 on the base end side, and an insertion hole 43 through which the arm body 23 of the arm 2 is inserted is formed in the diameter-enlarged portion 41.

The second support member 35 is a tubular body having an open beak shape with both sides cut out, and with the insertion portion 39 of the first support member 34 inserted into the insertion hole 38 of the base body 33, It is arranged around the insertion portion 39. Due to its beak shape, the second support member 35 constitutes an insertion hole portion 44 through which the arm body 23 of the arm 2 is inserted together with the insertion hole 43 of the first support member 34.

As shown in FIG. 9, the pair of lock members 36, 36 are arranged on the reduced diameter portion 42 of the first support member 34. A pair of inclined surfaces 45 is formed on the inner surface of the lock member 36 so as to extend along the outer peripheral surface of the reduced diameter portion 42. Further, an abutment surface 46 that is inclined so as to face the support rod 4 is formed on the outer surface of the lock member 36. In the reduced-diameter portion 42, an appropriate distance 1 is secured between the pair of lock members 36, 36 (see FIG. 9B).
When the insertion portion 39 of the first support member 34 is inserted into the insertion hole 38 of the base body 33, the flange 40 is adjacent to the one lock member 36. Further, when the second support member 35 is arranged around the insertion portion 39 of the first support member 34, the base end of the second support member 35 is adjacent to the other lock member 36.

In the base 3 thus configured, the height position of the base 3 with respect to the support rod 4 can be changed. Further, the first support member 34 can be rotated with respect to the base body 33 of the base 3, and the inclination of the arm 2 can be freely changed.

Here, as described above, when the operation member 24 is operated to be twisted, the arm main body 23 is widened as shown in FIG. 7B. By expanding the width of the arm body 23 in this way, the arm body 23 is stretched in the insertion hole portion 44, and as shown by an arrow x in FIG. A force in the opposite direction is applied to the support member 35. Therefore, the flange 40 of the first support member 35 and the base end of the second support member 35 are pushed to move the pair of lock members 36, 36 so as to approach each other (the distance 1 becomes shorter). As a result, the contact surfaces 46 of the pair of lock members 36, 36 are pressed against the support rod 4, so that the base 3 can be fixed to the support rod 4. Further, since the inclined surfaces 45 of the pair of lock members 36, 36 are pressed against the reduced diameter portion 42 of the first support member 34, the first support member 34 can be fixed to the base 3.

As described above, in the arm device according to the present embodiment, it is not necessary to install the air clutch and the structure around it, and with a simple structure, the operation of the operation member 24 is performed by one operation, and the frame member 8 is The ball 5 is fixed, the medical device 7 is fixed to the ball 5, the arm 2 is fixed to the base 3, the base 3 is fixed to the support rod 4, and the base body 33 of the base 3 is fixed. In contrast, the first support member 34 can be fixed.

Although the present invention has been described along with the embodiments, the above embodiments merely show examples of embodying the present invention, and the technical scope of the present invention is construed in a limited manner by these. It must not be. That is, the present invention can be implemented in various forms without departing from its technical idea or its main features.
INDUSTRIAL APPLICABILITY The present invention is applicable not only to a ball joint type holding device, but also to ball joints in general regardless of whether or not the balls 5 are divided.

Further, the combination of the arm devices described in the above embodiments is only an example, and for example, in the ball joint type holding device 1 to which the present invention is applied, the protruding member is not limited to the arm 2 and the protruding member comes in and out from the tip by a predetermined operation. It may be provided on the arm.

In the above embodiment, the rod member 17 functions as the contact member in the present invention, and the rod 21 functions as the protruding member in the present invention. However, one member is the contact member and the protruding member. May function as. According to the above-described embodiment, the rod 21 may function as the protruding member and the contact member, that is, the rod member 17 may be omitted and the rod 21 may directly contact the ball 5.

In the above embodiment, the chamfered portion 11 is formed on the outer peripheral surface of the ball 5 at a position overlapping the dividing line 9, but the chamfering portion 11 and the dividing line 9 are formed around the axis C ₂ of the insertion hole 6. You may make it arrange|position, shifting a phase. For example, the chamfered portion 11 may be arranged with a 90° phase shift with respect to the dividing line 9 around the axis C ₂ of the insertion hole 6 (this is referred to as type 1 here). In this case, the tip surface of the rod member 17 is made to be a flat surface so that it also serves as the locking surface portion 16.
Furthermore, depending on the mechanism and application of the ball joint to which the present invention is applied, the chamfered portion 11 may not be formed so as to connect the openings 6a and 6b at both ends of the insertion hole 6. For example, when the type 1 is described as a base, the chamfered portion 11 may be rotated 90 degrees around the axis of the dividing line 9.

In the above embodiment, the ball joint type holding device and the arm device for holding the medical device 7 are described, but the present invention can be widely applied as long as it holds a rod-shaped body.

1: Ball joint type holding device, 2: Arm, 3: Base, 4: Support rod, 5: Ball, 5a: Hemisphere, 6: Insertion hole, 6a, 6b: Opening, 7: Medical device, 8: Frame member, 9: dividing line, 10: groove, 11: chamfered portion, 12 protruding portion, 13: ring portion, 14: tubular portion, 15: through hole, 15a, 15b: opening edge, 15c: inner peripheral surface, 16 : Locking surface part, 17: Rod member, 18: Notch part, 21: Rod

Claims (8)

A ball,
A through hole is formed, and a frame member in which the ball is arranged inside the through hole,
The ball is configured to restrict rotation around an axis extending in the one radial direction ,
A ball joint , wherein an insertion hole for inserting a rod-shaped body is formed in the ball, and the ball joint functions as a holding device for the rod-shaped body . The inner peripheral surface of the through hole has a maximum diameter at the center between the opening edges at both ends thereof, and has a concave arc surface that reduces in diameter toward each of the opening edges. Ball joint. A locking surface portion is provided on a part of the inner peripheral surface of the through hole, and at the position where the locking surface portion is provided, the inner peripheral surface of the through hole is not the concave arc surface, The ball joint according to claim 2, wherein the ball is restricted from rotating around the axis. On the outer peripheral surface of the ball , a chamfered portion is formed in a band shape so as to pass through the openings at both ends of the insertion hole and along the entire circumference of the ball, and the chamfered portion faces the locking surface portion. ball joint according to claim 3, wherein the chamfered portion is characterized that you have been so as not to interfere with the locking surface when moved. The ball is divided by a dividing line passing through openings at both ends of the insertion hole,
The ball is fixed by contacting the ball with an abutting member that can move in and out from the radial direction of the through hole inward of the through hole, and the rod-shaped body that is inserted through the insertion hole is also fixed. The ball joint according to any one of claims 1 to 4, wherein the ball joint has a structure. The ball joint according to claim 5 , wherein the dividing line of the ball is arranged so as to be displaced from the position where the contact member moves in and out. The ball joint according to any one of claims 1 to 6 , wherein the axis is an axis of the insertion hole. The ball joint according to claim 5 or 6 ,
The ball joint is provided with an arm provided at the tip,
The arm device is characterized in that the arm includes a protruding member that moves in and out from the tip by a predetermined operation, and the protruding member causes the contact member to contact the ball.

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