Bending device

Claim 2

A bending device comprising: (a) a coil having an internal space therein, and comprising a number of turn portions juxtaposed in a direction of an axis of said coil; and (b) operating wire means for bending said coil, said operating wire means having a proximal end portion adapted to receive an operating force, said operating wire means having a distal end portion substantially fixed to a distal end portion of said coil; CHARACTERIZED in that: at least one pair of limitation members (33; 55) extending in an axial direction of said coil (31) and mounted respectively on diametrically-opposite portions of said coil, said limitation members engaging said turn portions (31a) of said coil to keep said turn portions at substantially constant intervals, and said coil being bendable in a direction perpendicular to a plane in which said pair of limitation members are disposed.

Claim 3

A bending device according to claim 1, in which said pair of limitation members (33; 55) extend over generally an entire length of said coil (31), and are disposed in a common plane.

Claim 4

A bending device according to claim 1, in which said coil (31) has first and second regions (M, N) arranged alternately in the axial direction of said coil, each of said first and second regions comprising a predetermined number of said turn portions (31a), a plurality of pairs of said limitation members (33) being provided, a pair of said limitation members being mounted respectively on diametrically-opposite sections of said turn portions of each of said first regions which sections are spaced from each other in a first direction (X), and a pair of said limitation members being mounted respectively on diametrically-opposite sections of said turn portions of each of said second regions which sections are spaced from each other in a second direction (Y) perpendicular to said first direction.

Claim 5

A bending device according to claim 1, in which each of said pair of limitation members comprises a corrugated strip (33), said corrugated strip having a number of support portions (33a) of a generally semi-circular cross-section juxtaposed along a length of said corrugated strip, and connecting portions (33b) each interconnecting respective adjacent ones of said support portions, and said turn portions (31a) of said coil (31) being fitted in and supported by said support portions, respectively.

Claim 6

A bending device according to claim 1, in which each of said pair of limitation members comprises a wire (55) which is wound on at least a half of an outer periphery of each of said turn portions (31a) of said coil (31), any adjacent ones of said turn portions being spaced from each other by a distance equal to a diameter of said wire.

Claim 7

A bending device comprising: a bellows having an internal space therein, and having a corrugated peripheral wall defined by first and second portions arranged alternately in a direction of an axis of said bellows, said first portions being bulged radially outwardly whereas said second portions are bulged radially inwardly; CHARACTERIZED by the provision of: (a) operating wire means (51 to 54) for bending said bellows (60), said operating wire means having a proximal end portion adapted to receive an operating force, said operating wire means having a distal end portion substantially fixed to a distal end portion of said bellows; and (b) at least one pair of independent limitation means (62; 63, 64; 69) for limiting an axial compression of said bellows, said pair of limitation means being arranged in an axial direction of said bellows and mounted respectively on diametrically-opposite portions of said peripheral wall of said bellows, each of said pair of limitation means including insertion portions fitted respectively in at least one of said first portions (60a) and second portions (60b) of said bellows, and said bellows being bendable in a direction perpendicular to a plane in which said pair of limitation means are disposed.

Claim 8

A bending device comprising: a bellows having an internal space therein, and having a corrugated peripheral wall defined by first and second portions arranged alternately in a direction of an axis of said bellows, said first portions being bulged radially outwardly whereas said second portions are bulged radially inwardly; CHARACTERIZED by the provision of: (a) operating wire means (51 to 54) for bending said bellows (60), said operating wire means having a proximal end portion adapted to receive an operating force, said operating wire means having a distal end portion substantially fixed to a distal end portion of said bellows; and (b) at least one pair of independent limitation means (62; 63, 64; 69) for limiting an axial compression of said bellows, said pair of limitation means being arranged in an axial direction of said bellows and mounted respectively on diametrically-opposite portions of said peripheral wall of said bellows, each of said pair of limitation means including insertion portions fitted respectively in at least one of said first portions (60a) and second portions (60b) of said bellows, and said bellows being bendable in a direction perpendicular to a plane in which said pair of limitation means are disposed.

Claim 9

A bending device according to claim 6, in which said pair of limitation means (62; 69) extend over generally an entire length of said bellows (60), and are disposed in a common plane.

Claim 10

A bending device according to claim 6, in which said peripheral wall of said bellows (60) has first and second regions (Q, P) arranged alternately in the axial direction of said bellows, each of said first and second regions comprising a predetermined number of said alternate first and second portions (60a, 60b) of said bellows, a plurality of pairs of said limitation means (63, 64) being provided, a pair of said limitation means being mounted respectively on diametrically-­opposite sections of each of said first regions which sections are spaced from each other in a first direction (X), and a pair of said limitation means being mounted respectively on diametrically-opposite sections of each of said second regions which sections are spaced from each other in a second direction (Y) perpendicular to said first direction.

Claim 11

A bending device according to claim 8, in which each of said limitation means comprises a row of alternate first and second pieces (63, 64) serving as said insertion portions, said first pieces being disposed inside said peripheral wall of said bellows (60), said second pieces being disposed outside said peripheral wall of said bellows, said first pieces being fitted in and fixedly secured to said first portions (60a) of said bellows, respectively, said second pieces being fitted in and fixedly secured to said second portions (60b) of said bellows, respectively, each of said first pieces having a projecting portion extending radially inwardly of an inner periphery of said second portion, said projecting portion having an insertion hole (63a) formed therethrough, and said wire operating means being passed through said insertion hole.

Claim 12

A bending device according to claim 6, in which each of said pair of limitation means comprises a limitation member (69) extending in the axial direction of said bellows (60), said limitation member being disposed outside said peripheral wall of said bellows in such a manner that said insertion portions (69a) are fitted respectively in said second portions (60b) of said bellows.

Claim 13

A bending device according to claim 6, in which each of said limitation means comprises a row of alternate first and second pieces (62, 63, 64) serving as said insertion portions, said first pieces being disposed inside said peripheral wall of said bellows (60), said second pieces being disposed outside said peripheral wall of said bellows, said first pieces being fitted in and fixedly secured to said first portions (60a) of said bellows, respectively, and said second pieces being fitted in and fixedly secured to said second portions (60b) of said bellows, respectively.

Claim 14

A bending device according to claim 11, in which each of said first and second pieces (62) has a spherical shape.

Claim 15

A bending device according to claim 6, in which a row of insertion holes (65) are formed through the corrugations of said peripheral wall of said bellows (60), said row of insertion holes being disposed on a straight line parallel to the axis of said bellows, and said operating wire means (51, 52) being passed through said row of insertion holes.

Claim 16

A bending device according to claim 6, in which a row of notches (66) are formed in the outer peripheries of said first portions of said bellows (60), said row of notches being disposed on a straight line parallel to the axis of said bellows, and said operating wire means (51, 52) being received in said row of notches.