BEARING STRUCTURE AND COVERING UNIT WITH THE BEARING STRUCTURE

Description

[Technical Field]

[0001] The present invention relates to a bearing structure for a drape that covers a surgical robot including a holder for holding an insertion member and relates also to a drape unit including the bearing structure.[Background Art]

[0002] The sterile drape for a surgical procedure described in Patent Document 1 includes: an exterior surface adjacent to a sterile field for performing the surgical procedure; an interior surface forming a cavity for receiving a non-sterile portion of a robotic surgical system; an integral cuff including a permanently folded cease of the above exterior surface and the above interior surface at an open end of the cavity and a marker on the permanently folded cease that specifies a sterile side and a non-sterile side of the drape; and a fastener for securing the above sterile drape to the above non-sterile portion while reducing the volume of the sterile drape. With such a configuration, it may be possible to increase visualization of the patient by reducing the size of the drape, allow for quick and simple installation, and improve the instrument sterile adaptor feature.

[0003] Patent Document 2 describes a bearing structure for a drape that covers a surgical robot. The bearing structure comprises an outer ring, a sealing member and an inner ring. A first drape is attached or attachable to the outer ring by fitting in a trapezoid groove. A second drape is attached to the inner ring in another trapezoid groove.

[0004] Patent Document 3 describes a bearing structure for a drape that covers a surgical robot. The bearing structure comprises a connector, a coupling element and a further connector for holding a first drape or second drape, respectively.

[0005] Patent Document 4 describes an interface structure for detachably interfacing a surgical robot arm to a surgical instrument, the interface structure comprising a main body; and a drive transfer element comprising a first portion and a second portion, the first portion being releasably engageable with a portion of the surgical robot arm and the second portion being releasably engageable with a portion of the surgical instrument; the drive transfer element being movable relative to the main body so as to enable transfer of drive between the surgical robot arm and the surgical instrument.

[0006] Patent Document 5 describes a patient introducer for use with a surgical robotic system.

[0007] Patent Document 6 describes a sterile interface for a surgical platform. The sterile interface is configured to allow for transmission of motion without dimensional inconsistencies between a non-sterile surgical platform and a sterile surgical instrument that are related to one another in a master-slave configuration.[Prior Art Documents][Patent Documents]

[0008] [Patent Document 1] JP5193049B [Patent Document 2] WO 2009 / 092701 A1 [Patent Document 3] WO 2019 / 150111 A1 [Patent Document 4] US 2019 / 167365 A1 [Patent Document 5] WO 2018 / 187069 A1 [Patent Document 6] WO 2016 / 097861 A1 [Summary of the Invention][Problems to be solved by the Invention]

[0009] In the treatment according to Patent Document 1, however, the arm unit of a robot or the insertion member attached to the tip of the arm unit may be rotated, and in such a case, the drape may be twisted because the relative angle between the arm unit with the drape and the insertion member without the drape is changed. In particular, in recent years, there are cases in which the above relative angle exceeds 360 degrees. In such cases, the drape may be broken by a large twist, and the robot's operation may be hindered, resulting in malfunction or narrowing of the movable range.

[0010] An object of the present invention is therefore to provide a bearing structure for a drape that covers a surgical robot, the bearing structure capable of reducing the possibility that the drape is broken even when there is a rotation operation such that the relative angle exceeds 360 degrees and also capable of reliably maintaining the separation between a clean area and an unclean area. Another object of the present invention is to provide a drape unit including such a bearing structure.[Means for solving the Problems]

[0011] To achieve the above objects, a bearing structure according to claim 1 and a drape unit according to claim 12 are provided. An aspect of the present invention provides a bearing structure for a drape that covers a surgical robot having an arm whose tip is provided with a holder that detachably holds an insertion member in a rotatable manner. The bearing structure includes: a ring-shaped fixing member suitable to be attached with respect to the arm in a state in which the holder is inserted inside the fixing member; and a ring-shaped rotating member suitable to be attached with respect to the fixing member in a slidably rotatable manner in a state in which the holder is inserted inside the rotating member. The rotating member is rotatable together with the holder. The drape includes: a first drape that covers the arm and can be attached to the fixing member; and a second drape that covers the holder and can be attached to the rotating member in a rotatable manner together with the rotating member.

[0012] In the bearing structure of the present invention, the fixing member includes: a ring-shaped base member that is suitable to be attached with respect to the arm; and a ring-shaped joint member that is suitable to be detachably attached with respect to the base member by fitting, and the rotating member is attached with respect to the joint member in a slidably rotatable manner.

[0013] In the bearing structure of the present invention, the base member and the joint member are detachably fitted to each other by fitting a fitting protrusion provided on one of the base member and the joint member and a fitting recess provided in another of the base member and the joint member to each other.

[0014] In the bearing structure of the present invention, the fitting protrusion is provided on an outer circumferential surface of the base member and the fitting recess is provided in an inner circumferential surface of the joint member, or the fitting protrusion is provided on the inner circumferential surface of the joint member and the fitting recess is provided in the outer circumferential surface of the base member.

[0015] In the bearing structure of the present invention, the fitting recess is provided in a linked manner with a guide groove extending along a circumferential direction of the fixing member and the rotating member, and the fitting protrusion is moved along the guide groove thereby to rotate and guide the joint member with respect to the base member, guiding the fitting protrusion into the fitting recess.

[0016] In the bearing structure of the present invention, the guide groove extends along a main axis direction from a fitting side end portion in the main axis direction and further extends in the circumferential direction of the fixing member and the rotating member. The main axis direction is an axial direction of the fixing member and the rotating member.

[0017] In the bearing structure of the present invention, the guide groove preferably has a tapered portion in which a depth of the groove decreases as the guide groove extends from its end portion in the main axis direction along the main axis direction.

[0018] In the bearing structure of the present invention, the fitting recess and the fitting protrusion include two or more pairs of fitting recesses and fitting protrusions provided in the circumferential direction of the fixing member and the rotating member, the fitting protrusions are preferably provided at positions at a predetermined distance in the main axis direction from the fitting side end portion in the main axis direction, and a member provided with the fitting protrusions is preferably guided to a member provided with the fitting recesses by rotating the member provided with the fitting protrusions while bringing the fitting protrusions into contact with non-fitting regions in which the guide groove is not provided in the fitting side end portion in the main axis direction of the member provided with the fitting recesses.

[0019] In the bearing structure of the present invention, the guide groove is formed to have a wider width than that of the fitting recess in the main axis direction.

[0020] In the bearing structure of the present invention, the fitting protrusions preferably have respective fitting side end portions in the main axis direction, the fitting side end portions preferably form a plane orthogonal to the main axis direction, and the non-fitting regions are preferably located on a plane orthogonal to the main axis direction.

[0021] In the bearing structure of the present invention, the fitting recess and the fitting protrusion include two or more pairs of fitting recesses and fitting protrusions provided in a circumferential direction of the fixing member and the rotating member.

[0022] In the bearing structure of the present invention, three or more of the fitting recesses and three or more of the fitting protrusions are preferably provided in the circumferential direction of the fixing member and the rotating member.

[0023] In the bearing structure of the present invention, at least some of the fitting recesses and fitting protrusions preferably have different intervals in the circumferential direction of the fixing member and the rotating member.

[0024] In the bearing structure of the present invention, the guide groove is preferably provided in a linked manner with the fitting recess via a restriction protrusion, and the restriction protrusion preferably restricts the fitting protrusion fitted in the fitting recess from returning to the guide groove.

[0025] In the bearing structure of the present invention, the base member and the joint member are preferably provided with respective fitting markers that indicate that the fitting protrusion has reached a position at which it is fitted into the fitting recess by rotating the joint member relative to the base member.

[0026] In the bearing structure of the present invention, the fitting marker provided on the base member and the fitting marker provided on the joint member are preferably arranged at a same position as each other in the circumferential direction of the fixing member when the fitting protrusion has reached the position at which it is fitted into the fitting recess.

[0027] In the bearing structure of the present invention, the base member is preferably provided with an initial position marker that indicates a position at which the fitting protrusion is entered into the guide groove.

[0028] In the bearing structure of the present invention, the first drape is preferably fixed to an outer circumferential surface of the joint member, and the base member and the joint member preferably have a gap having a length that is at least twice a thickness of the first drape in an axial direction of the fixing member and the rotating member.

[0029] In the bearing structure of the present invention, the fixing member preferably has a protruding edge portion that protrudes outward in a radial direction at an end portion of the fixing member in an axial direction, and the rotating member attached to the fixing member in the slidably rotatable manner preferably comes into contact with the protruding edge portion thereby to be prevented from coming off from the fixing member.

[0030] In the bearing structure of the present invention, the rotating member preferably has a tongue portion that protrudes outward in the radial direction at an end portion of the rotating member in the axial direction, the fixing member preferably has a groove portion recessed inward adjacent to the protruding edge portion in the axial direction, and the tongue portion preferably engages with the groove portion.

[0031] In the bearing structure of the present invention, the base member is preferably composed of a metal, and the joint member and the rotating member are preferably composed of a resin material having durability against sterilization.

[0032] In the bearing structure of the present invention, the fitting protrusion preferably has a shape that protrudes in a hemispherical shape.

[0033] In the bearing structure of the present invention, the fitting protrusion preferably has a spherical portion and a biasing portion that biases the spherical portion in an outward direction.

[0034] Another aspect of the present invention provides a drape unit including: any form of the bearing structure as described above; the first drape attached to the fixing member; the second drape attached to the rotating member; and a separator that is provided in a linked manner with the second drape and is located between the insertion member and the holder to cover the holder.[Effect of the Invention]

[0035] According to the present invention, not only when the relative angle of the insertion member with respect to the arm unit is less than 360 degrees, but also when the insertion member is operated to rotate so as to exceed 360 degrees, it is possible to reduce the possibility that the drape which covers the rotating member, fixing member, holding body, arm unit, etc. is broken and also to reliably maintain the separation between a clean area and an unclean area.[Brief Description of Drawings]

[0036] FIG. 1 is a perspective view illustrating the external configuration of a holding body of a medical robot including a bearing structure according to an embodiment of the present invention. FIG. 2 is an exploded perspective view illustrating the schematic configuration of the holding body illustrated in FIG. 1. FIG. 3 is an exploded perspective view illustrating the configuration of the bearing structure according to an embodiment of the present invention. FIGS. 4(a) and 4(b) are perspective views of the configuration of a joint member in an embodiment of the present invention as viewed from different directions. FIGS. 5(a) and 5(b) are perspective views of the configuration of a base member in an embodiment of the present invention as viewed from different directions. FIG. 6 is an enlarged perspective view illustrating a fitting recess of the base member and its periphery. FIG. 7(a) is a cross-sectional view taken along the line VII-VII' of FIG. 3 and FIG. 7(b) is a cross-sectional view illustrating a state in which the rotating member, joint member, and base member illustrated in FIG. 7(a) are assembled. FIG. 8 is a set of views illustrating the attaching positions of a first drape and a second drape, wherein FIG. 8(a) is a side view illustrating a state before attaching a drape unit and FIG. 8(b) is a side view illustrating a state in which the drape unit is attached to the holding body side. FIG. 9 is a set of views illustrating the configuration of a rotating member in an embodiment of the present invention, wherein FIG. 9(a) is a plan view as viewed along the direction of an axis of rotation and FIG. 9(b) is a perspective view. FIG. 10(a) is a plan view of the configurations of fitting markers and an initial position marker in an embodiment of the present invention as viewed from above and FIG. 10(b) is a plan view illustrating the positions of the fitting markers and initial position marker before and after fitting of the joint member and the base member. FIG. 11(a) is a rear view illustrating the configuration of the joint member in an embodiment of the present invention and FIG. 11(b) is a rear view illustrating the configuration of a joint member according to a modified example. FIG. 12 is an exploded perspective view illustrating the configuration of a bearing structure according to a modified example. FIG. 13 is a perspective view illustrating the configuration of a joint member in another modified example. FIG. 14 is a cross-sectional view conceptually illustrating the configuration of a fitting protrusion in still another modified example. [Embodiments for Carrying out the Invention]

[0037] Hereinafter, the bearing structure according to an embodiment of the present invention will be described in detail with reference to the drawings. The present embodiment represents an example in which the bearing structure is applied to a medical robot, but the bearing structure of the present invention is not limited to this.

[0038] In each figure, X-Y-Z coordinates are illustrated as reference coordinates. In the following description, the Z1-Z2 direction is referred to as an up-down direction, the X1-X2 direction is referred to as a front-rear direction, and the Y1-Y2 direction is referred to as a left-right direction. The X1-X2 direction and the Y1-Y2 direction are orthogonal to each other, and the X-Y plane including the X1-X2 direction and the Y1-Y2 direction is orthogonal to the Z1-Z2 direction. In the following description, a state in which the lower side (Z2 side) is viewed from the upper side (Z1 side) may be referred to as a plan view.(Overall Structure)

[0039] The medical robot of the present embodiment includes an arm unit that can change its direction and angle, and a holding body 10 illustrated in FIG. 1 is provided at the tip of the arm unit. From the front end of the holding body 10, a holder 21 and a separator 22 that is arranged so as to cover the holder 21 extend frontward. An insertion member inserted into the patient's body to be treated by the medical robot is detachably attached with respect to the holder 21 by using the separator 22. The posture of the insertion member is changed in accordance with the changes of the direction and angle of the arm unit. Examples of the insertion member includes a treatment tool and an endoscope used for the treatment.

[0040] As illustrated in FIG. 2, the holder 21 and the separator 22 are attached to the holding body 10 via a switch unit 31, a bearing structure 40, and a bearing member 32 that are arranged in this order from the front to the rear. The bearing member 32 is fixed to the holding body 10 via an annular bearing plate 33. The holder 21 and the separator 22 are provided integrally with the switch unit 31. The bearing member 32 is, for example, a rolling bearing whose outer ring is fixed to the holding body 10 and whose inner ring can rotate relative to the outer ring.

[0041] As illustrated in FIGS. 2 and 3, the bearing structure 40 includes a rotating member 41, a joint member 42, and a base member 43 that are all ring-shaped. Rear portions of the holder 21 and the separator 22 are inserted inside the above members of the bearing structure 40, and the holder 21 and the separator 22 are provided integrally with the rotating member 41.

[0042] The joint member 42 and the base member 43 are detachably attached to each other by fitting and constitute a fixing member 44. The base member 43 is attached with respect to the holding body 10. The rotating member 41 is attached with respect to the joint member 42 of the fixing member 44 in a slidable manner along a circumferential direction C.

[0043] The base member 43 is preferably composed of a metal from the viewpoint of durability against sliding with the joint member 42, and for example, aluminum or duralumin is used.

[0044] The joint member 42 and the rotating member 41 are preferably composed of a resin material from the viewpoint of slidability and durability against sterilization, and for example, ABS resin, polycarbonate, and polyacetal are suitable.

[0045] By configuring the rotating member 41 and the fixing member 44 with such materials, it is possible to prevent damage when sterilizing a member with which the drape contacts and to ensure the slidability for a long period of time, and damage due to sliding over a long period of time can be reduced.

[0046] The holder 21, the separator 22, the switch unit 31, and the rotating member 41 are supported by the bearing member 32 in a rotatable manner and are driven by a motor (not illustrated) to rotate around an axis of rotation AX along the front-rear direction (X1-X2 direction).

[0047] As illustrated in FIGS. 8(a) and 8(b), a front opening portion 51a of a tubular first drape 51 is fixed along an outer circumferential surface 142d on the rear side of the joint member 42 of the bearing structure 40. The first drape 51 extends rearward from the joint member 42 and covers the holding body 10 and the surgical robot including an arm unit on which the holding body 10 is provided.

[0048] The fixing member 44 is composed of two components of the base member 43 fixed to the holding body 10 and the joint member 42 detachable from the base member 43, and the first drape 51 can therefore be easily removed from the holding body 10 by attaching the first drape 51 to the joint member 42.

[0049] A front opening portion 52a of a tubular second drape 52 is provided in a linked manner with the separator 22 so as to be fixed from its front end portion 22a to its rear end portion 22b. This allows the separator 22 and the second drape 52 to be integrated, and the lower surface of the separator 22 is placed in the second drape 52.

[0050] On the other hand, a rear opening portion 52b of the second drape 52 is fixed along an outer circumferential surface 141 of the rotating member 41.

[0051] Thus, the separator 22 and the rotating member 41 are attached with respect to the holding body 10 from the state in which the second drape 52 is attached. In this operation, the holder 21 and the switch unit 31 are inserted into the rotating member 41, and the separator 22 is attached to an upper surface 21b of the holder 21. According to this step, as illustrated in FIG. 8(b), the front surface and lower surface of the holder 21 are covered with the second drape 52 from a front end portion 21a located on the front side of the front end portion 22a of the separator 22, and the upper surface 21b is covered with the separator 22. When the rotating member 41 rotates relative to the fixing member 44, the second drape 52 rotates integrally with the rotating member 41, the separator 22, and the holder 21.(Fixing Member)

[0052] The joint member 42 has an inner circumferential surface 42a provided with two fitting protrusions 42b and 42c (see FIGS. 3 and 11(a)) while the base member 43 has an outer circumferential surface 43a provided with two fitting recesses 43b and 43c (see FIGS. 3, 5(a), and 5(b)) on the joint member 42 side (X1 side, front side). The joint member 42 and the base member 43 are detachably fitted to each other by fitting the fitting protrusions 42b and 42c into the fitting recesses 43b and 43c, respectively. In this fitting, two side surfaces of each of the fitting protrusions 42b and 42c (two surfaces facing each other in the front-rear direction) and two inner side surfaces of each of the fitting recesses 43b and 43c (two inner surfaces facing each other in the front-rear direction) come into contact with each other thereby to maintain the fixed state. In this fitting state, the joint member 42 covers the outside of the base member 43 in the fitting portion, and the first drape 51 is attached to the joint member 42 as described above; therefore, in the fixing member 44, the joint member 42 and the base member 43 can be fitted to each other in a state in which a clean component covers an unclean component.

[0053] As illustrated in FIGS. 4(a) and 4(b), the two fitting protrusions 42b and 42c are provided at the rearmost end of the joint member 42 in the front-rear direction (X1-X2 direction). The two fitting protrusions 42b and 42c are formed so as to protrude inward (toward the axis of rotation AX side) at positions symmetrical with respect to the axis of rotation AX in the circumferential direction C of the ring-shaped joint member 42.

[0054] The two fitting recesses 43b and 43c are formed so as to extend along the circumferential direction C at positions symmetrical with respect to the axis of rotation AX in the circumferential direction C of the ring-shaped base member 43 (see FIGS. 3, 5(a), and 5(b)).

[0055] As illustrated in FIG. 5(a), the fitting recesses 43b and 43c are provided in a linked manner with guide grooves 61 and 71, respectively. One guide groove 61 extends rearward from the foremost end (end portion on the fitting side with the joint member 42) in the front-rear direction of the base member 43, that is, in the main axis direction which is the axial direction of the fixing member 44 and the rotating member 41. The guide groove 61 further extends along the circumferential direction C from the position corresponding to the fitting recess 43b in the front-rear direction. The other guide groove 71 also extends rearward from the foremost end (end portion on the fitting side with the joint member 42) in the front-rear direction of the base member 43 and further extends in the circumferential direction C from the position corresponding to the fitting recess 43c. Thus, when viewed along a radial direction R of the base member 43, the guide grooves 61 and 71 are both formed so as to bend in an L shape.

[0056] The fitting protrusions 42b and 42c are provided symmetrically in the circumferential direction C of the joint member 42 while the fitting recesses 43b and 43c are also provided symmetrically in the circumferential direction C of the base member 43, and therefore one of the two fitting protrusions 42b and 42c corresponds to one of the two fitting recesses 43b and 43c, and the other fitting protrusion and the other fitting recess correspond to each other. Thus, one pair of fitting protrusions and one pair of fitting recesses are provided in the circumferential direction C of the fixing member 44. For this reason, when the joint member 42 and the base member 43 are fitted together, they can be easily moved along the axis of rotation AX, and it is therefore possible to prevent the joint member 42 and the base member 43 from biting and damaging each other during the fitting and prevent the inner surfaces of the fitting recesses from being scraped due to the slanting of the fitting protrusions.

[0057] One fitting recess 43b and the guide groove 61 provided in a linked manner with the fitting recess 43b will then be described in detail. The other fitting recess 43c and the guide groove 71 provided in a linked manner with the fitting recess 43c have symmetrical shapes to those of the fitting recess 43b and the guide groove 61 with respect to the axis of rotation AX, so the detailed description thereof will be omitted.

[0058] As illustrated in FIG. 6, the guide groove 61 provided in a linked manner with the fitting recess 43b has a tapered portion 62 that increases its thickness so as to reduce the depth of the guide groove 61 as the guide groove 61 extends along the main axis direction (X1-X2 direction) from the end portion on the fitting side with the joint member 42. By providing the tapered portion 62, it becomes easy to guide the fitting protrusion (either the fitting protrusion 42b or 42c) into the guide groove 61.

[0059] The guide groove 61 is provided in a linked manner with the fitting recess 43b via a restriction protrusion 63 in the circumferential direction C. The restriction protrusion 63 has approximately the same thickness as that of the outer circumferential surface 43a on the front side of the base member 43 and is provided so that the outer surface of the restriction protrusion 63 is located outside both the fitting recess 43b and the guide groove 61 in the radial direction R. This allows the fitting protrusion (either the fitting protrusion 42b or 42c) fitted in the fitting recess 43b to come into contact with the side surface of the restriction protrusion 63 in the circumferential direction C, so that the fitting protrusion is restricted from returning to the guide groove 61. Thus, the rotational movement of the joint member 42 with respect to the base member 43 is restricted by the restriction protrusion 63, and a trouble is therefore less likely to occur that the fitting is disengaged due to the rotational movement of the rotating member 41 attached to the joint member 42.

[0060] By providing the restriction protrusions 63 and 73, when the joint member 42 and the base member 43 are fitted to each other and the fitting is released, click feeling (attaching feeling or detaching feeling) can be given to the operator in the operation of getting across the restriction protrusions 63 and 73. Hence, even in a situation in which it is difficult to visually recognize the joint member 42 or the base member 43 due to the presence of the drape, the completion of attachment / detachment can be easily confirmed.

[0061] The guide groove 61 is formed to have wider widths than those of the fitting recess 43b in the main axis direction (X1-X2 direction) and the circumferential direction C. In other words, the guide groove 61 is formed to have wider widths than those of the fitting protrusion 42b in the main axis direction and the circumferential direction C. This allows the fitting protrusion 42b to be easily guided into the guide groove 61. Moreover, in the guide groove 61, the fitting protrusion 42b comes into contact with the rear end wall in the guide groove 61 to allow for easy positioning in the main axis direction, and from this state, the fitting protrusion 42b is moved along the circumferential direction C thereby to be easily and reliably guided into the fitting recess 43b.

[0062] Also in the guide groove 71, a tapered portion 72 and a restriction protrusion 73 are provided in a similar manner to the tapered portion 62 and restriction protrusion 63 of the guide groove 61 (see FIG. 5(b)).

[0063] As illustrated in FIGS. 3 and 7(a), the joint member 42 has a groove portion 142b and a protruding edge portion 142c on an outer circumferential surface 142a on the rotating member 41 side (X1 side). The protruding edge portion 142c is provided at the front end portion of the outer circumferential surface 142a in a flange shape extending outward in the radial direction R. The groove portion 142b is provided in a linked manner with the protruding edge portion 142c to have an annular shape behind the protruding edge portion 142c on the outer circumferential surface 142a, and is provided so as to be recessed inward in the radial direction R from the outer circumferential surface 142a.

[0064] As illustrated in FIG. 10(a), the base member 43 has a rear-side outer circumferential surface 43e, on which an initial position marker M0 is provided at a position corresponding to the center of the guide groove 61 in the left-right direction (Y1-Y2 direction) so as to extend in the front-rear direction. The initial position marker M0 corresponds to the position at which the fitting protrusion 42b is introduced into the guide groove 61. The above outer circumferential surface 43e is provided with a fitting marker M11 so as to extend in the front-rear direction at a position corresponding to the center of the fitting recess 43b in the left-right direction.

[0065] On the other hand, the joint member 42 has a rear-side outer circumferential surface 142d, on which a fitting marker M12 is provided at a position corresponding to the center of the fitting protrusion 42b in the left-right direction so as to extend in the front-rear direction. The fitting marker M12 of the joint member 42 and the fitting marker M11 of the base member 43 are arranged at the same position as each other in the circumferential direction C of the fixing member 44 (see the right figure of FIG. 10(b)) when the fitting protrusion 42b has reached a position at which it is fitted into the fitting recess 43b.

[0066] By providing the fitting markers M11 and M12 and the initial position marker M0, when the joint member 42 and the base member 43 are fitted to each other and the fitting is released, confirmation of the fitting and its release can be reliably performed by the visual sense in addition to the click feeling due to getting across the restriction protrusions 63 and 73, and it is therefore possible to prevent a situation in which the fitting between the joint member 42 and the base member 43 is incomplete, etc.

[0067] The initial position marker M0 and the two fitting markers M11 and 12 are provided in a linear shape having a predetermined width in each of the front-rear direction and the circumferential direction C, but other shapes may be adopted, provided that the fitting marker M12 of the joint member 42 can be reliably aligned with the initial position marker M0 or fitting marker M11 of the base member 43. Additionally or alternatively, the markers may be formed by printing or the like or formed as recesses or protrusions on the surface to be formed with the markers, which may be preferred because the operator can sense the markers by tactile sense.(Rotating Member)

[0068] As illustrated in FIGS. 3, 9(a), and 9(b), the rotating member 41 has four tongue portions 41b, 41c, 41d, and 41e at the front end portion of an inner circumferential surface 41a. The four tongue portions 41b, 41c, 41d, and 41e are provided at identical angular intervals with respect to the axis of rotation AX, which is the central axis of the ring-shaped rotating member 41, and are provided so as to protrude inward from the inner circumferential surface 41a. When the rotating member 41 is fitted to the joint member 42, the four tongue portions 41b, 41c, 41d, and 41e are movable in the circumferential direction C in the groove portion 142b of the joint member 42 and come into contact with the protruding edge portion 142c thereby to restrict the movement in the front-rear direction. The groove portion 142b of the joint member 42 has a depth sufficient to prevent the tongue portions 41b, 41c, 41d, and 41e from coming off.(Assembly of Fixing Member and Fitting of Fixing Member and Rotating Member)

[0069] The base member 43 is fixed to the outer ring of the bearing member 32 thereby to be fixed to the holding body 10.

[0070] The joint member 42 is then moved in the front-rear direction so as to cover the outer circumferential surface 43a on the front side of the base member 43. At this time, in the circumferential direction C, the initial position marker M0 on the base member 43 and the fitting marker M12 on the joint member 42 are arranged so as to coincide with each other (left figure of FIG. 10(b)), and the fitting protrusions 42b and 42c move in the front-rear direction while sliding in the corresponding guide grooves 61 and 71 in the base member 43 along the front-rear direction and reach the positions on the rearmost side (X2 side) in the guide grooves 61 and 71. Subsequently, the joint member 42 is rotated in the circumferential direction C until the fitting marker M12 of the joint member 42 coincides with the fitting marker M11 of the base member 43 (position at which the fitting protrusion 42b is fitted into the fitting recess 43b) (right figure of FIG. 10(b)). This allows the fitting protrusions 42b and 42c to be moved from the guide grooves 61 and 71 into the fitting recesses 43b and 43c beyond the restriction protrusions 63 and 73 and fitted into the fitting recesses 43b and 43c. Through this series of operations, the joint member 42 and the base member 43 are fitted to each other, and the movement of the joint member 42 with respect to the base member 43 is restricted in the front-rear direction (main axis direction) and the circumferential direction C.

[0071] On the other hand, in the release of fitting between the joint member 42 and the base member 43, the joint member 42 is rotated by the force larger than a predetermined value in the circumferential direction opposite to that when the joint member 42 is fitted with respect to the base member 43. Then, when the fitting protrusions 42b and 42c get across the restriction protrusions 63 and 73 and the fitting marker M12 of the joint member 42 reaches a position corresponding to the initial position marker M0 of the base member 43, the fitting protrusions 42b and 42c are released from the fitting recesses 43b and 43c, respectively, and the joint member 42 can therefore be removed from the base member 43. The above predetermined value is appropriately set in accordance with the spec of the surgical robot and the like.

[0072] Here, the fitting protrusions 42b and 42c share a plane on which their rear end surfaces are orthogonal to the extending direction of the axis of rotation AX (main axis), and this plane is flush with a rear end surface 42d of the joint member 42 (see FIGS. 4(a) and 7). In other words, a part of the rear end surface 42d of the joint member 42 constitutes each of the rear end surfaces of the fitting protrusions 42b and 42c, and other parts form non-fitting regions that do not fit to the fitting recess 43b or 43c of the base member 43. With such a configuration, when the joint member 42 is fitted with respect to the base member 43, even in a state in which the fitting protrusions 42b and 42c and the fitting recesses 43b and 43c do not face each other in the axial direction, at least one of the joint member 42 and the base member 43 can be easily guided to a position at which the fitting protrusions 42b and 42c and the fitting recesses 43b and 43c correspond to each other through bringing the rear end surface 42d of the joint member 42 and a front end surface 43d of the base member 43 into contact with each other and sliding them along the circumferential direction C.

[0073] The rotating member 41 is attached with respect to the joint member 42 before it is fitted to the base member 43. The rotating member 41 is attached with respect to the joint member 42 by being moved along the front-rear direction so as to cover the outer circumferential surface 142a on the front side of the joint member 42 with the inner circumferential surface 41a (see FIGS. 10(a) and 10(b)). In this attaching, the tongue portions 41b, 41c, 41d, and 41e of the rotating member 41 are engaged in the groove portion 142b of the joint member 42, and the rotating member 41 is thereby attached to the joint member 42 in a state of being rotatable around the axis of rotation AX.

[0074] In the above assembly process, before the joint member 42 to which the rotating member 41 is fixed is fitted to the base member 43 (state of FIG. 8(a)), the front opening portion 51a of the first drape 51 is fixed to the outer circumferential surface 142d on the rear side of the joint member 42, such as by adhesion, and the rear opening portion 52b of the second drape 52 is fixed with respect to the outer circumferential surface 141 of the rotating member 41, such as by adhesion. The front opening portion 52a of the second drape 52 is fixed with respect to the front end portion 22a and rear end portion 22b of the separator 22. By fixing the first drape 51 and the second drape 52 in this way, a drape unit D is configured to include the bearing structure 40, which includes the rotating member 41, the joint member 42, and the base member 43, the first drape 51 attached to the fixing member 44, the second drape 52 attached to the separator 22 and the rotating member 41, and the separator 22 which covers the holder 21 from above.

[0075] As illustrated in FIG. 7(b), a gap S1 is formed between the joint member 42 and the base member 43 along the circumferential direction C in the front-rear direction (direction along the axis of rotation AX). In the front-rear direction, the length of the gap S1 is twice or more the thickness of the first drape 51. By providing the gap S1 with such a size, when the joint member 42 is fitted with respect to the base member 43 in a state in which the first drape 51 is fixed to the joint member 42, a trouble of tucking the first drape 51 into the gap S1 is less likely to occur.

[0076] Through the above steps, the holder 21, the separator 22, the switch unit 31, the rotating member 41, the fixing member 44, the bearing member 32, and the bearing plate 33 are attached with respect to the holding body 10. Here, the fixing member 44 is fixed to the holding body 10. On the other hand, the rotating member 41 can rotate relative to the fixing member 44 around the axis of rotation AX. The rotating member 41 is integrated with the holder 21 and the separator 22, which are rotatable together with the inner ring of the bearing member 32, and can rotate around the axis of rotation AX.

[0077] This allows the separator 22 whose relative position is fixed with respect to the holder 21 to rotate as the holder 21 rotates, and even when the second drape 52 rotates accordingly, the rotating member 41 to which the second drape 52 is attached rotates relative to the fixing member 44; therefore, the fixing member 44 to which the first drape 51 is attached does not rotate, and even if the holder 21 rotates beyond 360 degrees, the first drape 51 is less likely to be twisted, and the damage of the first drape 51 can be prevented.

[0078] Moreover, the guide groove 71 is formed to have an L shape when viewed along the radial direction R by extending the guide groove 71 along the main axis direction from the fitting side end portion in the main axis direction (direction in which the axis of rotation AX extends) which is the axial direction of the fixing member 44 and the rotating member 41 and further extending the guide groove 71 along the circumferential direction C of the fixing member 44 and the rotating member 41, so that two operations in the axial direction and the circumferential direction C are performed as the fitting operation for the joint member 42 with respect to the base member 43; therefore, the fitting is less likely to come off even if there is vibration or the like, and the fitting state is easy to stabilize.

[0079] When the rotating member 41 is attached with respect to the joint member 42, a front surface 41f of the rotating member 41 comes into contact with the protruding edge portion 142c in the main axis direction because the protruding edge portion 142c is provided on the joint member 42 of the fixing member 44. This can prevent the rotating member 41 from detaching from the joint member 42, and even when the second drape 52 attached to the rotating member 41 is pulled frontward in the axial direction, for example, a trouble is less likely to occur that the rotating member 41 comes off from the joint member 42 to expose the unclean portion.

[0080] Moreover, when the rotating member 41 is attached to the joint member 42, the tongue portions 41b, 41c, 41d, and 41e provided at the end portion in the axial direction of the rotating member 41 are fitted in the groove portion 142b of the joint member 42 in a state of being slidable along the circumferential direction C. This allows the rotating member 41 to stably rotate along the circumferential direction C while being restricted in the movement along the axial direction.

[0081] Modified examples will be described below.

[0082] In the above embodiment, the joint member 42 is provided with the fitting protrusions 42b and 42c and the base member 43 is provided with the fitting recesses 43b and 43c, but alternatively to this, another configuration is also possible in which the base member 43 is provided with fitting protrusions and the joint member 42 is provided with fitting recesses.

[0083] Moreover, in the above embodiment, the joint member 42 is fitted from the outside of the base member 43, but conversely, the base member may be fitted from the outside of the joint member.

[0084] In the above embodiment, the two fitting protrusions 42b and 42c and the two fitting recesses 43b and 43c are provided at equal angle intervals of 180 degrees when viewed along the main axis direction (X1-X2 direction). FIG. 11(a) illustrates the fitting protrusions 42b and 42c provided on the joint member 42.

[0085] In contrast, three or more pairs of fitting protrusions and fitting recesses may be provided. Three or more pairs can stabilize the fitting state when fitting the fixing member 44 and the rotating member 41 to each other, and the fitting protrusions can therefore be easily fitted into the fitting recesses. FIG. 11(b) illustrates an example in which the joint member 42 is provided with three fitting protrusions 132b, 132c, and 132d at equal angle intervals of 120 degrees. In the case of this configuration, the fitting recesses are also provided so as to correspond to the fitting protrusions 132b, 132c, and 132d at equal angle intervals of 120 degrees. With this configuration, in the process of fitting the joint member 42 to the base member 43, when they are subjected to relative rotation while bringing the front end surface 43d of the base member 43 into contact with the three fitting protrusions 132b, 132c, and 132d, the presence of the three fitting protrusions can stabilize the rotation and can also efficiently and reliably transmit the force required for fitting the base member 43 and the joint member 42 to each other.

[0086] In the example illustrated in FIG. 11(b), the three fitting protrusions 132b, 132c, and 132d are provided at equal angle intervals of 120 degrees, but if they are distributed, for example, at 110 degrees, 140 degrees, and 110 degrees rather than setting equal angle intervals of the fitting protrusions, the attachment is possible only at determined positions in the circumferential direction, and it is therefore possible to prevent the drape from being attached in a twisted state when fitting the fitting protrusions and the fitting recesses to each other.

[0087] Such a configuration in which the angle intervals are not the same is preferred because the same effect can be obtained also when applied to a configuration in which two fitting protrusions and two fitting recesses are provided. Specific examples of such cases include those in which the angle intervals between the fitting protrusions and between the fitting recesses are set to 170 degrees and 190 degrees.

[0088] The fitting protrusion 42b of the above embodiment is disposed at a position at which its rear end surface is flush with the rear end surface 42d of the joint member 42, but alternatively to this, as illustrated in FIG. 12, a fitting protrusion 242b may be disposed at a position at a predetermined distance from the rear end surface 42d of the joint member 42 to the front side (X1 side) in the main axis direction. The same applies to the other fitting protrusion 42c of the above embodiment.

[0089] When the fitting protrusion 242b is disposed so as to be shifted inward from the rear end surface 42d of the joint member 42 in this way, upon the fitting of the joint member 42 and the base member 43 to each other, at least one of the joint member 42 and the base member 43 can be easily rotated around the axis of rotation AX while maintaining a state in which the fitting protrusion 242b is in contact with a non-fitting region on the front end surface 43d of the base member 43. The fitting protrusion 242b can therefore be easily guided to the guide groove 61 or 71 of the base member 43.

[0090] In the above embodiment, the fitting protrusions 42b and 42c and the fitting recesses 43b and 43c are arranged symmetrically with respect to the axis of rotation AX in the circumferential direction C, and fitting at two positions is possible. In contrast, the fitting protrusions and the fitting recesses may be arranged asymmetrically, and the intervals may be different between clockwise and counterclockwise in the circumferential direction C. When three or more fitting protrusions and three or more fitting recesses are provided, an arrangement may be adopted in which at least a part or some of the intervals are not the same as the other intervals. With such an arrangement, the fitting position of the joint member 42 and the base member 43 in the circumferential direction C is fixed to one, and the orientation of the separator 22 can therefore be easily adjusted.

[0091] The surface shape of the fitting protrusions 42b and 42c of the above embodiment is a shape corresponding to the bottom surface shape of the fitting recesses 43b and 43c. That is, when the bottom surface of the fitting recesses 43b and 43c is a curved surface having the same curvature as that of the outer circumferential surface 43a on the front side, a curved surface facing thereto is adopted, while when the bottom surface of the fitting recesses 43b and 43c is a flat surface, a flat surface facing thereto is adopted.

[0092] In contrast, another form may be adopted in which the surface shape of the fitting protrusions is a hemispherical shape protruding along the radial direction R (shape of fitting protrusions 342b and 342c in FIG. 13), and the inner surface shape of the fitting recesses is a recessed shape corresponding to the above hemispherical shape. Still another form is also possible in which, instead of the fitting recesses 43b and 43c, protrusions that hemispherically protrude outward in the radial direction R are provided on the outer circumferential surface 43a on the front side of the base member 43, and recesses corresponding to the shape of the above protrusions are provided on the inner circumferential surface 42a of the joint member 42. According to these forms, workability can be improved in both the fitting of the joint member 42 and the base member 43 to each other and the release of the fitting, and the protrusions and the recesses can be easily processed.

[0093] Furthermore, as illustrated in FIG. 14, a fitting protrusion 442c may be configured to include a spherical portion 442h and a biasing portion 442s that biases the spherical portion 442h outward from the inner circumferential surface 42a, that is, in a direction toward the axis of rotation AX in the radial direction R. In the example illustrated in FIG. 14, the spherical portion 442h is hemispherical, but it may be a sphere, while a compression spring is illustrated as the biasing portion 442s, but a spring other than the compression spring, a rubber material, or the like can also be used, provided that it can bias the spherical portion 442h along the radial direction R. With such a configuration, it is not necessary to control the elastic deformation of the fitting recesses, and damage to the fitting recesses can be reduced.[Description of Reference Numerals]

[0094] 10 Holding body 21 Holder 21a Front end portion of holder 21b Upper surface 22 Separator 22a Front end portion of separator 22b Rear end portion of separator 31 Switch unit 32 Bearing member 33 Bearing plate 40 Bearing structure 41 Rotating member 41a Inner circumferential surface of rotating member 41b, 41c, 41d, 41e Tongue portion 41f Front surface 42 Joint member 42a Inner circumferential surface of joint member 42b, 42c Fitting protrusion 42d Rear end face of joint member 43 Base member 43a Outer circumferential surface on front side of base member 43b, 43c Fitting recess 43d Front end surface of base member 43e Outer circumferential surface on rear side of base member 44 Fixing member 51 First drape 51a Front opening portion 52 Second drape 52a Front opening portion 52b Rear opening portion 61, 71 Guide groove 62, 72 Tapered portion 63, 73 Restriction protrusion 132b, 132c, 132d Fitting protrusion 141 Outer circumferential surface of rotating member 142a Outer circumferential surface on front side of joint member 142b Groove portion 142c Protruding edge portion 142d Outer circumferential surface on rear side of joint member 242b Fitting protrusion 342b, 342c Fitting protrusion 442c Fitting protrusion 442h Spherical portion 442s Biasing portion AX Axis of rotation (main axis) C Circumferential direction D Drape unit M0 Initial position marker M11, M12 Fitting marker R Radial direction S1 Gap

Claims

1. A bearing structure (40) for a drape that covers a surgical robot having an arm whose tip is provided with a holder (21) that detachably holds an insertion member in a rotatable manner, the bearing structure (40) comprising: a ring-shaped fixing member (44) suitable to be attached to the arm in a state in which the holder (21) is inserted inside the fixing member (44); and a ring-shaped rotating member (41) suitable to be attached to the fixing member (44) in a slidably rotatable manner in a state in which the holder (21) is inserted inside the rotating member (41), the rotating member (41) being rotatable together with the holder (21), the drape comprising: a first drape (51) that covers the arm and can be attached to the fixing member (44); and a second drape (52) that covers the holder (21) and can be attached to the rotating member (41) in a rotatable manner together with the rotating member (41), wherein the fixing member (44) comprises a ring-shaped base member (43) that is suitable to be attached to the arm; and a ring-shaped joint member (42) that is suitable to be detachably attached to the base member (43) by fitting, and the rotating member (41) is attached to the joint member (42) in a slidably rotatable manner; and wherein the base member (43) and the joint member (42) are detachably fitted to each other by fitting a fitting protrusion (42b, 42c) provided on one of the base member (43) and the joint member (42) and a fitting recess (43b, 43c) provided in another of the base member (43) and the joint member (42) to each other, wherein the fitting protrusion (42b, 42c) and the fitting recess (43b, 43c) have the following features (I) and (II): (I) the fitting protrusion (42b, 42c) is provided on an outer circumferential surface of the base member (43) and the fitting recess (43b, 43c) is provided in an inner circumferential surface of the joint member (42), or the fitting protrusion (42b, 42c) is provided on the inner circumferential surface of the joint member (42) and the fitting recess (43b, 43c) is provided in the outer circumferential surface of the base member (43); (II) the fitting recess (43b, 43c) and the fitting protrusion (42b, 42c) comprise two or more pairs of fitting recesses (43b, 43c) and fitting protrusions (42b, 42c) provided in a circumferential direction of the fixing member (44) and the rotating member (41), wherein the fitting recess (43b, 43c) is provided in a linked manner with a guide groove (61, 71) extending along a circumferential direction of the fixing member (44) and the rotating member (41), and the fitting protrusion (42b, 42c) is moved along the guide groove (61, 71) thereby to rotate and guide the joint member (42) with respect to the base member (43), guiding the fitting protrusion (42b, 42c) into the fitting recess (43b, 43c), wherein the guide groove (61, 71) has the following features (i) and (ii): (i) the guide groove (61, 71) extends along a main axis direction from a fitting side end portion in the main axis direction and further extends in the circumferential direction (C) of the fixing member (44) and the rotating member (41), wherein the main axis direction is an axial direction of the fixing member (44) and the rotating member (41); (ii) the guide groove (61, 71) is formed to have a wider width than that of the fitting recess (43b, 43c) in a main axis direction that is an axial direction of the fixing member (44) and the rotating member (41).

2. The bearing structure (40) according to claim 1, wherein the bearing structure (40) has at least one feature of the group consisting of the following features (A) and (B): (A) the guide groove (61, 71) has a tapered portion (62, 72) in which a depth of the groove decreases as the guide groove (61, 71) extends from its end portion in the main axis direction along the main axis direction; (B) the fitting recess and the fitting protrusion comprise two or more pairs of fitting recesses and fitting protrusions provided in the circumferential direction of the fixing member and the rotating member, the fitting protrusions are provided at positions at a predetermined distance in the main axis direction from the fitting side end portion in the main axis direction, and a member provided with the fitting protrusions is guided to a member provided with the fitting recesses by rotating the member provided with the fitting protrusions while bringing the fitting protrusions into contact with non-fitting regions in which the guide groove is not provided in the fitting side end portion in the main axis direction of the member provided with the fitting recesses.

3. The bearing structure (40) according to claim 2, wherein, in a case in which the guide groove has said feature (B), at least some of the fitting recesses and fitting protrusions have different intervals in the circumferential direction of the fixing member and the rotating member.

4. The bearing structure (40) according to claim 1, wherein the base member (43) and the joint member (42) are provided with respective fitting markers (M11, M12) that indicate that the fitting protrusion (42b, 42c) has reached a position at which it is fitted into the fitting recess (43b, 43c) by rotating the joint member (42) relative to the base member (43).

5. The bearing structure (40) according to claim 4, wherein the bearing structure (40) has at least one feature of the group consisting of the following features (Alpha) and (Beta): (Alpha) the fitting marker (M11) provided on the base member (43) and the fitting marker (M12) provided on the joint member (42) are arranged at a same position as each other in the circumferential direction (C) of the fixing member (44) when the fitting protrusion (42b, 42c) has reached the position at which it is fitted into the fitting recess (43b, 43c); (Beta) the base member (43) is provided with an initial position marker (M0) that indicates a position at which the fitting protrusion (42b, 42c) is entered into the guide groove (61, 71).

6. The bearing structure (40) according to claim 1, wherein the first drape (51) is fixed to an outer circumferential surface (142d) of the joint member (42), and the base member (43) and the joint member (42) have a gap (S1) having a length that is at least twice a thickness of the first drape (51) in an axial direction of the fixing member (44) and the rotating member (41).

7. The bearing structure (40) according to claim 1, wherein the fixing member (44) has a protruding edge portion (142c) that protrudes outward in a radial direction (R) at an end portion of the fixing member (44) in an axial direction, and the rotating member (41) attached to the fixing member (44) in the slidably rotatable manner comes into contact with the protruding edge portion (142c) thereby to be prevented from coming off from the fixing member (44).

8. The bearing structure (40) according to claim 1, wherein the base member (43) is composed of a metal, and the joint member (42) and the rotating member (41) are composed of a resin material having durability against sterilization.

9. The bearing structure (40) according to claim 1, wherein the bearing structure (40) has at least one feature of the group consisting of the following features (a) and (b): (a) the fitting protrusion (442c) has a shape that protrudes in a hemispherical shape; (b) the fitting protrusion (442h) has a spherical portion and a biasing portion (442s) that biases the spherical portion (442h) in an outward direction.

10. The bearing structure according to any one of claims 1 to 9, wherein the second drape (52) is fixed along the outer circumferential surface (141) of the rotating member (41).

11. The bearing structure according to any one of claims 1 to 10, wherein (iii) the guide groove (61, 71) is provided in a linked manner with the fitting recess (43b, 43c) via a restriction protrusion (63, 73), and the restriction protrusion (63, 73) restricts the fitting protrusion (42b, 42c) fitted in the fitting recess (43b, 43c) from returning to the guide groove (61, 71).

12. A drape unit (D) comprising: the bearing structure (40) according to any one of claims 1 to 11; the first drape (51) attached to the fixing member (44); the second drape (52) attached to the rotating member (41); and a separator (22) that is provided in a linked manner with the second drape (52) and is located between the insertion member and the holder (21) to cover the holder (21).