EP-3777641-B1 - ARM DEVICE

Inventors

• HARAGUCHI, DAISUKE
• TADANO, KOTARO
• KANAZAWA, NORIAKI

Dates

Publication Date

20260506

Application Date

20180910

Claims (6)

1. An arm device (1, 201, 301, 401) comprising: a first gimbal portion (21, 421) configured to rotatably support an instrument about a first rotational axis (101) extending along an axis line of the instrument; a second gimbal portion (22, 422, 522) configured to rotate the instrument about a second rotational axis (102) extending along a direction intersecting the first rotational axis; a distal portion (30) configured to rotate the instrument about a third rotational axis (103) extending to intersect a plane including the first rotational axis and the second rotational axis, an arm portion (40, 60) configured to support the distal portion (30), the arm portion comprising a first arm portion (40) having at least one parallel link (41A, 41B) and a second arm portion (60) having at least one parallel link (61A, 61B); an actuator (42, 62) configured to drive the parallel link (41A, 41B, 61A, 61B) to thereby move a position of the distal portion (30); two gravity compensators (63A, 63B) provided to the second arm portion (60) and configured to apply a force to move the distal portion (30) upward on the parallel link of the second arm portion (61A, 61B); and one gravity compensator (43) provided on the first arm portion (40) and configured to apply a force to move the distal portion (30) upward on the parallel link of the first arm portion (41A, 41B), the third rotational axis having an inclination angle greater than 0 degree and less than 90 degrees when a horizontal direction is defined as 0 degree and an upper vertical direction is defined as 90 degrees.
2. The arm device according to claim 1, wherein the third rotational axis has an inclination angle of 45 degrees.
3. The arm device according to claim 1 or 2, further comprising: a link portion (241, 261) having one end relatively rotatably mounted on a support and the other end relatively rotatably mounted on the distal portion; and a drive portion (245, 265) configured to change a relative position of the distal portion with respect to the support, and to maintain an attitude of the distal portion constant.
4. The arm device according to any one of claims 1 to 3, wherein the actuator is an air pressure actuator configured to be driven by receiving air supply.
5. The arm device according to any one of claims 1 to 4, wherein the first arm portion extends along a horizontal direction and is configured to rotate about a rotational axis line extending vertically.
6. The arm device according to any one of claims 1 to 5, further comprising: a holding portion (80) that is attachable to and detachable from a place where the instrument is to be arranged for use.

Description

TECHNICAL FIELD The present disclosure relates to an arm device, and particularly relates to an arm device suitable for endoscopic surgery and endoscopic examinations using an endoscope, and for general surgery. BACKGROUND ART Endoscopic surgery using an endoscope has been known. In the endoscopic surgery, an instrument holder to hold an instrument, such as an endoscope and a forceps. A known instrument holder is an instrument holder having a gimbal portion and an arm portion and capable of operating an instrument three-dimensionally. The instrument holder is also capable of holding an instrument at any position. Also, in endoscopic examinations using an endoscope and, for example, general open abdominal surgery (hereinafter, endoscopic surgery, endoscopic examinations, and general surgery are also collectively referred to as "examinations and operations".), more and more examinations and procedures are being performed using such an instrument holder to hold an instrument. Under this situation, it is known that, for example, an endoscope observation angle at which an endoscope is to be held during endoscopic surgery varies for each target disease, and each target disease has a suitable observation angle. Examples of the endoscope observation angle frequently used in endoscopic surgery are as below. In digestive surgery, frequently used is an endoscope observation angle to hold an endoscope obliquely downward relative to a surgical bed. In respiratory surgery, frequently used is an endoscope observation angle to hold an endoscope in a substantially vertical attitude relative to a surgical bed. In urological surgery, frequently used is an endoscope observation angle to hold an endoscope in a substantially horizontal attitude relative to a surgical bed. Moreover, surgical tools for use with the endoscope are each held and used at an appropriate angle corresponding to the target disease and the endoscope observation angle. In order to correspond to different endoscope observation angles as described above, regarding the instrument holder, for example, instrument holders with various configurations have been proposed (see, for example, Patent Documents 1 and 2). PRIOR ART DOCUMENTS PATENT DOCUMENTS Patent Document 1: Japanese Patent No. 3579379Patent Document 2: Japanese Unexamined Utility Model Application Publication No. H3-13113 Patent document JP2003053684A discloses a prior art arm device, and describes a parallel robot or parallel kinematics mechanism provided for uses such as robotics or machining. The mechanism comprises a fixed base, a main arm, and a first and second support arm to position and orient an object in a cylindrical space with at least three degrees of freedom and retained inclination. The main arm includes an end component for supporting the object and linkage means to retain the inclination of the end component with respect to the base for all positions and orientations of the end component. Patent document US2006245894A1 discloses another prior art arm device, comprising two gravity compensators in the form of springs. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION The aforementioned gimbal portion has three rotational axes intersecting one another. The gimbal portion with this configuration may assume a specific attitude in which two rotational axes are located in the same direction plane depending on rotational positions of the three rotational axes. In the gimbal portion assuming the specific attitude, original three degrees of freedom will be reduced to two degrees of freedom. If the gimbal portion takes an attitude close to the specific attitude, it will be difficult to operate the instrument holder in a specific direction, and an operation range of the instrument will be narrowed. In order to allow use of the instrument holder without difficulty in various endoscopic surgery, the gimbal portion is required not to take the specific attitude within a range of the endoscope observation angle. However, the technique disclosed in Patent Document 1 or 2 does not achieve a configuration in which the gimbal portion of the instrument holder can be avoided from assuming the specific attitude. In the configuration disclosed in Patent Document 1, when a medical manipulator 1 is held in a substantially horizontal attitude, a rotational axis 106 overlaps a rotational axis 104. In this situation, the attitude of the gimbal portion is the specific attitude. In case of using the configuration disclosed in Patent Document 1 for endoscopic surgery in the urological surgery, operability might be impaired. In this regard, if the configuration disclosed in the Patent Document 1 is arranged with a distal portion 15 (including the rotational axis 104) inclined by 90°, the gimbal portion can be avoided from assuming the specific attitude. Thus, when an instrument holder with the distal portion 15 inclined by 90° is used for endoscopic surgery in the urological surgery, operability might be