JP2013119151A5 - - Google Patents

Description

Finger joint structure

  The present invention relates to a finger joint structure.

  A finger joint structure such as a robot includes a plurality of finger members and hinge portions (joints) that connect the members to each other so as to be rotatable.

  As a method for rotating the plurality of joints, for example, a method of rotating a joint by winding a wire around each joint and transmitting the power of the driving means to each joint via the wire (Patent Document 1), There is proposed a method of directly driving a joint and rotating a joint directly (Patent Document 2), and a finger joint structure (Patent Document 3) capable of driving three joints by one driving means.

JP 2001-277175 A JP 2002-113681 A International Publication No. 2008/026574

  In the method of Patent Document 1, a driving unit and a wire are required for each joint, and the joint rotates by pulling the wire. Therefore, there is a problem that a wire for bending and extending the joint is required. is there. Moreover, in the method of patent document 2, it is necessary to provide a drive means for every joint, and there exists a problem that a joint structure enlarges. Furthermore, the method of Patent Document 3 has a problem that a complicated structure is required to drive three joints by one driving means.

  As described above, the conventional finger joint structure requires a complicated structure and a large structure, and it is difficult to simplify and miniaturize the structure.

  An object of the present invention is to provide a simple and small finger joint structure.

  In order to solve the above-mentioned problems, the present inventors have conducted extensive studies, and as a result, in a finger joint structure configured in the order of a finger part, a palm part, and a base part from the distal end side to the proximal end side. The finger part is composed of a hollow body formed by connecting a plurality of cylindrical bodies at end faces, and at least one wire penetrating the hollow body, and the distal end of the hollow body and the distal end of the wire are joined. The proximal end of the hollow body is fixed to the distal end of the palm, and at least one of the wires further penetrates the palm and reaches the base, so that the proximal end of the wire is proximal to the base. The present inventors have found that by pulling, the finger portion can express a rigid bent shape.

The present invention relates to a finger joint structure including a finger portion having a distal end, a palm portion extending to the finger portion, and a base portion provided at a proximal end of the palm portion (excluding a medical retractor). In the joint structure, the finger portion is composed of a hollow body in which a plurality of cylindrical bodies having irregular cross-sections are connected to each other at an end surface, and at least one wire penetrating the hollow body. At least one of the bodies has an end face that is not perpendicular to the axial direction, and at least one of the wires has a profile of a major axis that is at least 80% of the minor axis of the inner diameter of the hollow body; The distal end of the hollow body and the distal end of the wire are joined, the proximal end of the hollow body is fixed to the distal end of the palm, and at least one of the wires further penetrates the palm To reach the base, and at the base, by pulling the proximal end of the wire proximally Finger portion can express a bent shape.

  In one embodiment, two or more wires penetrate the hollow body.

  In one embodiment, the shape of the irregular cross section of the cylinder is an ellipse, a race track, a rectangle, a square, a triangle, or a pentagon.

  In one embodiment, the shape of the irregular cross section of the wire is an ellipse, a racetrack, a rectangle or a trapezoid.

  In one embodiment, the material of the cylinder is selected from stainless steel, titanium, a titanium alloy, a shape memory alloy, a superelastic alloy, or a composite thereof.

  In one embodiment, the material of the wire is selected from stainless steel, titanium, titanium alloy, shape memory alloy, superelastic alloy, or a composite thereof.

  In one embodiment, the finger portion is covered with a resin cover.

  According to the present invention, a simple and small finger joint structure can be provided. The finger joint structure of the present invention quickly develops a bent shape by operating the base. An arbitrary bent shape can be expressed by appropriately setting the angle of the end face of the adjacent cylindrical body of the hollow body constituting the finger part. By combining a plurality of finger joint structures, an object can be gripped freely by the expressed bent shape. By positively interposing the elasticity of the wire in the transmission of the driving force, the impact on the grasped object can be reduced.

It is a schematic diagram which shows one embodiment of the side shape of the finger joint structure of this invention. It is a schematic diagram which shows one embodiment of the finger joint structure of this invention. It is a schematic diagram which shows one embodiment of the cross-sectional shape of the finger | toe part of the finger joint structure of this invention. It is a schematic diagram which shows one embodiment of the side shape of the finger joint structure of this invention. It is a schematic diagram which shows one embodiment of the side shape (a) and planar shape (b) of the finger joint structure of this invention.

  As used herein, the term “distal end” refers to the portion furthest from the operator, and the term “proximal end” refers to the portion closest to the operator.

  In this specification, the term “bent shape” refers to an arbitrary shape formed by a curve, and includes a three-dimensional shape.

  Referring to FIGS. 1 and 2, the finger joint structure 1 of the present invention includes a finger part 11, a palm part 12 extending from the finger part 11, and a base part 13 provided at a proximal end of the palm part 12. The dimension of each part is not specifically limited.

  When the finger part 11 does not exhibit a bent shape, the finger part 11 takes a linear shape (FIG. 1A and FIGS. 2A-1 and 2A-1 ′). The bent shape is not particularly limited, and examples thereof include an arc shape (FIG. 1 (b) and FIGS. 2 (a-2) and (a-2 ')).

  The finger part 11 includes a hollow body 2 formed by connecting a plurality of cylindrical bodies 21 at end surfaces and at least one wire 3 penetrating the hollow body 2. The finger joint structure 1 of the present invention can be miniaturized by reducing the major axis of the cross section of the wire 3. For example, the maximum outer diameter of the finger part 11 can be 3 mm or less.

  The cylinder 21 has an irregular cross section. Here, the irregular shape means a special shape different from the standard shape. The standard shape of the cross-sectional shape of the cylindrical body 21 is a circle, and examples of the irregular shape include an elliptical shape, a racetrack shape, a rectangular shape, a square shape, a triangular shape, and a pentagonal shape.

  The number of cylinders 21 is not particularly limited as long as the finger part 11 can be formed. Preferably, it is 3 or more. The greater the number of cylinders 21, the smoother the bent shape that appears.

  Referring to FIG. 2, the finger part 11 has a large number of cylinders 21 and can grasp or wrap up an object by expressing a bent shape.

At least one of the cylinders 21 has an end surface that is not perpendicular to the axial direction. For example, when the cross-sectional shape of the cylindrical body 21 is a flat shape as shown in FIG. 3A, the end surface is an axis in the side surface shape of the cylindrical body 21 with the flat surface up and down as shown in FIG. An inverted V-shaped or V-shaped notch is formed at a certain angle θ _{1 to} θ ₃ from a plane perpendicular to the direction. In the case of θ ₁ , since the upper side L _{1 of the} side surface shape is longer than the lower side L ₂ , it is an inverted V-shaped notch. For theta ₂ is the same. On the other hand, in the case of theta _3, the upper side of the side shape is shorter than the lower side, a V-shaped notch. The magnitudes of the angles θ _{1 to} θ ₃ may be the same or different. The notch having the angle θ may be formed on either one of the two end faces of the cylindrical body 21 or on both. When forming both, both angles (theta) may be the same and may differ.

Alternatively, as shown in FIG. 4 (a), the inverted V-shaped notch and the V-shaped notch are provided on both the upper side and the lower side of the side surface shape with a certain angle θ ₁ and θ ₂ from the vertical plane. It may be formed. The magnitudes of the angles θ ₁ and θ ₂ may be the same or different. The height H ₂ of the V-shaped notch of height H ₁ and the lower side of the inverted V-shaped notch upper side may be the same, may be different, the height of the cylindrical body 21 H and H ₁ and H ₂ satisfy the relationship of H = H ₁ + H ₂ . By providing notches on both the upper side and the lower side of the cylinders 21 that are connected, the direction in which the finger portion 11 bends can be set to the lower side as shown in FIG. It can also be on the upper side as in c).

Further, the bent shape is not limited to a shape on the same plane. For example, as shown in FIG. 3B, when the cross-sectional shape of the cylindrical body 21 is rectangular, as shown in FIG. 5, in the side surface shape (a) of the cylindrical body 21 with the long side face up and down, the end face is An inverted V-shaped notch is formed at a constant angle θ ₁ and θ ₂ from a plane perpendicular to the axial direction, and in the planar shape (b), the end surface is constant from the plane perpendicular to the axial direction. at an angle theta ₃ to form an inverted V-shaped notch. Thus, by changing the surface on which θ is formed by the cylindrical body 21, a three-dimensional bent shape is possible. This is the same when the cross-sectional shape of the cylinder 21 is not rectangular.

  The hollow body 2 formed by connecting a plurality of cylindrical bodies 21 at the end faces can take a linear shape in accordance with the shape of the wire 3 penetrating the hollow body 2, and an inverted V having an angle θ between the end faces of the adjacent cylindrical bodies 21. A letter-shaped notch is formed. When the hollow body 2 is pressed from both ends by pulling to the base side of the wire 3, the hollow body 2 is hollow until the angle between the end faces of the adjacent cylindrical bodies 21 becomes 0 °, that is, until the end faces are in close contact with each other. A bent shape as shown in FIGS. 1B, 2A-2 and 2A-2, and FIGS. 4B and 4C is developed together with the wire 3 penetrating the body 2. FIG.

  The angle θ is appropriately set according to the bending shape that is manifested. Further, how to arrange the cylindrical body 21 having the end face of the angle θ is appropriately set according to the bent shape to be expressed.

  The dimension of the cylinder 21 is not specifically limited. The ratio (%) (for example, flatness) of the minor axis to the major axis in the outer diameter of the cylindrical body 21 is not particularly limited. The bending directivity of the hollow body 2 can be increased as the ratio is increased, but if the ratio is too large, the rigidity of the hollow body 2 is decreased. The cylinder thickness of the cylinder 21 is not particularly limited as long as the rigidity of the finger portion 11 can be ensured.

  Although the material of the cylinder 21 is not specifically limited, Preferably it is a metal. Examples of the metal include stainless steel, titanium, titanium alloy, shape memory alloy, superelastic alloy, and composites thereof. Examples of stainless steel include SUS304, SUS316, and SUS316L. Examples of titanium and titanium alloy include pure titanium and β titanium. Examples of the shape memory alloy and superelastic alloy include nitinol (nickel-titanium alloy). As a material of the cylindrical body 21, a resin may be used as long as it is rigid. Examples of the resin include polyamide and polytetrafluoroethylene (PTFE).

  The number of wires 3 is appropriately set according to the rigidity of the hollow body 2 and the wires 3. Usually, it is 1-6, preferably 2-4.

  At least one of the wires 3 has a deformed cross section having a major axis that is smaller than the major axis of the hollow body 2 and at least 80% of the minor axis, and preferably larger than the minor axis. The standard shape of the cross section of the wire is a circle, and examples of the irregular shape include an elliptical shape, a racetrack shape, a rectangular shape, and a trapezoidal shape. FIG. 3A shows an example of a racetrack shape. FIG. 3B shows an example of a rectangular shape. FIG. 3C shows an example of a trapezoidal shape.

  By making the major axis of the wire 3 at least 80% of the minor axis of the inner diameter of the cylindrical body 21, preferably larger than the minor axis, the flat surface or long side surface of the hollow body 2 and the major axis surface of the irregular cross section of the wire 3 are matched. It is possible to prevent the wire 3 from freely rotating around the axis in the hollow body 2. The ratio (%) of the sum of the minor diameters of the deformed cross sections of all the wires 3 penetrating the cylindrical body 21 to the minor axis of the inner diameter of the cylindrical body 21 is not particularly limited, but the shape of the hollow body 2 is maintained (preventing deviation). In order to ensure the rigidity, it is preferably 60% or more, more preferably 80% or more. The ratio (%) of the major axis of the wire 3 having the largest major axis of the wire 3 penetrating the cylinder 21 to the major axis of the inner diameter of the cylinder 21 is not particularly limited, but is preferably preferably 60% or more, More preferably, it is 80% or more.

  The material of the wire 3 is not particularly limited, but is preferably a metal. Examples of the metal include stainless steel, titanium, titanium alloy, shape memory alloy, superelastic alloy, and composites thereof. Examples of stainless steel include SUS304, SUS316, and SUS316L. Examples of titanium and titanium alloy include pure titanium and β titanium. Examples of the shape memory alloy and superelastic alloy include nitinol (nickel-titanium alloy). The shape of the wire may be, for example, a spring shape or a mesh shape.

  When there are two or more wires 3, the cross-sectional shape of each wire may be the same or different. For example, as shown in FIG. 3A, in the case of one set of wires composed of three wires 31 having the same cross-sectional shape with a small major axis and one wire 32 with a different cross-sectional shape having a large major axis Since the wire 31 has high rigidity and high linear directivity, and since the wire 32 has low rigidity and high bending directivity, it is possible to control the bent shape expression and the linear shape restoring property.

  When there are two or more wires 3, the material of each wire may be the same or different. For example, in the case of one set of wires in which two of the four wires 3 shown in FIG. 3A are high-strength stainless steel and the other two are superelastic nickel-titanium alloys, the stainless steel is rigid. Highly linear directivity due to its high rigidity while bending shape is high, while nickel-titanium alloy has low rigidity and high elasticity due to its super elasticity, while flexibility when bending shape is manifested (straight shape recovery) Is expensive.

  In this way, by appropriately selecting and combining the number of wires 3, the cross-sectional shape and material of each wire, and optimally controlling the balance of characteristics such as bending shape development, rigidity at the time of bending shape development, and linear shape restoration can do.

  By making the finger part 11 have the above-described configuration, the bending direction of the cylindrical body 21 can be made constant, and the finger part 11 has a flat surface side or long side surface side of the hollow body 2, that is, an irregular cross section of the wire 3. The bending directivity increases in the minor axis direction, and the bending shape expression and the rigidity at the time of bending shape expression increase.

  The distal end of the hollow body 2 and the distal end of the wire 3 are joined by a joining member 4, and the proximal end of the hollow body 2 is fixed to the distal end of the palm 12 by a fixing member 5. The joining portion may or may not have the joining member 4 that reinforces the joining, and the securing portion may or may not have the fixing member 5 that reinforces the securing.

  At least one of the wires 3 further penetrates the palm 12 and one end reaches the base 13. The cross-sectional shape of the wire 3 penetrating the palm portion 12 may be the same as or different from the cross-sectional shape at the palm portion 12 and the cross-sectional shape at the finger portion 11. For example, the cross-sectional shape of the palm portion 12 may be a circle. The material of the wire 3 penetrating the palm portion 12 may be the same as or different from the material of the palm portion 12 and the material of the finger portion 11. The proximal end of the remaining wire 3 that does not penetrate the palm 12 may be fixed to the distal end of the palm 12 or may not be fixed, but is preferably not fixed.

  The finger portion 11 is usually linear in accordance with the shape of the wire 3 that penetrates the hollow body 2, but in the base portion 13, the proximal end of the wire 3 that penetrates the palm portion 12 is pulled to the base side, so that the finger portion 11 is hollow. The body 2 is pressed from both ends, and the end surfaces of the respective cylinders 21 can be brought into close contact with each other to develop a bent shape. By loosening the traction force, the pressing force is weakened and the expression of the bent shape is released.

  There may be two or more wires 3 that penetrate the palm portion 12 and control the expression of the shape of the finger portion 11 by pulling the proximal end toward the base side. In the case of two or more, for example, the wire 3 used for the control is selected even in the finger portion 11 provided with notches on both the upper side and the lower side of the connecting cylinder 21 as shown in FIG. Thus, the bending direction of the finger part 11 can be determined. For example, the wire 3 closest to the bending direction side is used for control.

  The length of the wire 3 that penetrates the palm 12 is appropriately set according to the length of the finger joint structure 1.

  The palm 12 is a hollow cylinder, and at least one of the wires 3 passes through the cylinder. The material of the palm portion 12 is not particularly limited as long as it is rigid. Examples thereof include stainless steel such as SUS304, resin such as polyamide and polytetrafluoroethylene (PTFE), and stainless steel coated with a resin.

  The finger part 11 and the palm part 12 preferably have smooth surfaces. In particular, the finger part 11 may be covered with the resin cover 6 (FIGS. 2A-2 and 2A-2 '). Preferably, the region from the distal end to the proximal end of the finger portion 11 and the boundary region between the finger portion 11 and the palm portion 12 are in close contact with and covered with the resin cover 6. The resin cover 6 can not only relieve the impact on the object to be grasped when the finger part 11 grasps the object, but can also protect the finger joint structure. Examples of the resin include polyamide, polyolefin, fluorine-based resin (PTFE, Teflon (registered trademark) FEP, fluon (registered trademark) PFA, etc.), silicone, polyurethane, and polyethylene terephthalate (Daclon (registered trademark)). The thickness of the resin cover 6 is preferably 10 to 250 μm.

  The finger part 11 and the palm part 12 may have an uneven surface to prevent slipping.

  The base portion 13 can be operated to change the shape of the finger portion 11. The method of changing the shape of the finger part 11 is a method of pulling the proximal end of the wire 3 penetrating the palm part 12 toward the base part 13 as described above.

  The shape and structure of the base portion 13 are not particularly limited as long as they have the functions described above. It is easy for the operator to handle and can be the size and shape normally employed in the art.

  In the finger joint structure 1 of the present invention, the finger portion 11 exhibits a bent shape. The finger part 11 grips an object by an operation by the base part 13.

  According to the present invention, a simple and small finger joint structure can be provided. The finger joint structure of the present invention quickly develops a bent shape by operating the base. An arbitrary bent shape can be expressed by appropriately setting the angle of the end face of the adjacent cylindrical body of the hollow body constituting the finger part. By combining a plurality of finger joint structures, an object can be gripped freely by the expressed bent shape. By positively interposing the elasticity of the wire in the transmission of the driving force, the impact on the grasped object can be reduced.

The finger joint structure of the present invention is a structure for deforming the tip of the linear body by remote operation, and can be used as a finger joint structure of a robot or a medical instrument. Examples of the robot include a robot that plays an active role in a place where it is difficult for a person to work such as a disaster robot . The finger joint structure of the present invention can also be used as an electrode for electrolytic processing and an industrial endoscope.

  The finger joint structure of the present invention has a simple structure and can be supplied at low cost.

DESCRIPTION OF SYMBOLS 1 Finger joint structure 11 Finger part 12 Palm part 13 Base part 2 Hollow body 21 Cylindrical body 3 Wire 31 Wire of cross-sectional shape with small long diameter 32 Wire of cross-sectional shape with large long diameter 4 Joining member 5 Fixing member 6 Resin cover L ₁ Flat surface Long side L _{2 of} the cylindrical body 21 with the up and down sides L ₂ Short side of the side surface of the cylindrical body 21 with the flat surface up and down L ₃ Long side L ₄ of the planar shape of the cylindrical body 21 with the long side surfaces up and down Short side H of flat shape of cylinder 21 with long side surface up and down H Height of shape of cylinder 21 with flat side or long side surface up and down (H ≦ W)
W The width of the shape of the cylindrical body 21 with the flat surface or the long side surface up and down (H ≦ W)
H ₁ of the shape of the tubular body 21 having a flat surface or a long side surface and below the upper side of the inverted V-shaped notch of height H ₂ of the flat surface or the long side surfaces were in a vertical cylindrical body 21 in the shape of the lower side V-shaped notch height θ ₁ , θ ₂ , θ ₃ Angle formed by the end face of the cylindrical body 21 and a plane perpendicular to the axial direction

Claims (7)

A finger joint structure comprising: a finger portion having a distal end; a palm portion extending from the finger portion; and a base portion provided at a proximal end of the palm portion,
The finger portion is composed of a hollow body formed by connecting a plurality of cylindrical bodies having irregular cross sections at end faces, and at least one wire penetrating the hollow body,
At least one of the cylindrical bodies has an end face that is not perpendicular to the axial direction;
The wire has a deformed cross section having a major axis that is 80% or more of the minor axis of the inner diameter of the hollow body;
The distal end of the hollow body and the distal end of the wire are joined;
The proximal end of the hollow body is secured to the distal end of the palm;
At least one of the wires further penetrates the palm and reaches the base, and at the base, the proximal end of the wire is pulled toward the base, whereby the finger portion develops a bent shape. obtain,
Finger joint structure (excluding medical retractors) . The finger joint structure according to claim 1, wherein two or more wires penetrate the hollow body (excluding a medical retractor) . The finger joint structure according to claim 1 or 2, wherein a shape of the irregular cross section of the cylindrical body is an ellipse, a racetrack, a rectangle, a square, a triangle, or a pentagon , except for a medical retractor. ) The finger joint structure according to any one of claims 1 to 3, wherein the deformed cross-sectional shape of the wire is an ellipse, a racetrack, a rectangle, or a trapezoid (except for a medical retractor) . The finger joint structure according to any one of claims 1 to 4, wherein the material of the cylindrical body is selected from stainless steel, titanium, a titanium alloy, a shape memory alloy, a superelastic alloy, or a composite thereof . Excluding medical retractors) . The material of the wire, stainless steel, titanium, titanium alloys, shape memory alloys are selected from a superelastic alloy or a composite thereof, finger joint structure according to any one of claims 1 5 (however, the medical Except for retractor) . The finger joint structure according to any one of claims 1 to 6, wherein the finger portion is covered with a resin cover (excluding a medical retractor) .