Bobbin chuck mechanism of a bobbin holder

Abstract

 To provide a bobbin holder the critical speed of which is high and resulting in a high speed rotation of the bobbin and from which an accomplished package can be detached smoothly a curved or bending laminated chuck piece 13 is disposed between retention rings 14a, 14b in order to swell to the radial direction by compressing a peripheral part 15 of a cylindrical member 9 for inserting a bobbin B to the axis direction, and a spacer 50 is provided between the retention rings 14a, 14b for limiting the swell of the chuck piece 13 to the radial direction (Fig. 1).

Description

Field of the Invention

[0001] The present invention relates to a bobbin holder which retains a bobbin for rewinding melt spinning yarn etc. and more particularly to a bobbin chuck mechanism which enables the high velocity rotation by enhancing natural frequency.

Background of the Invention

[0002] As illustrated in Figure 13, a bobbin holder 150 comprises a cylindrical member 151 for inserting into a bobbin 152 and a bobbin chuck mechanism 154 for fixing the bobbin 152 into which the cylindrical member 151 is inserted so as to rotate with the cylindrical member.

[0003] The bobbin chuck mechanism comprises a chuck piece 153 for gripping a plurality of the bobbins 152 provided on the peripheral surface of the cylindrical member 151 from the inside, a spacer 155 provided between the chuck pieces 153 and a pressure member 160 for pressing the chuck piece 153 and the spacer 155 to the axial direction.

[0004] A plurality of the chuck piece 153 is disposed at almost regular intervals to the peripheral direction on the peripheral surface of the cylindrical member 151 and plurality of the chuck pieces 153 is provided along the axial direction, and is arranged to grip a plurality of the bobbins 152 on the periphery of the cylindrical member 151.

[0005] The pressure member 160 comprises a piston 156 provided slidably to the axial direction in a hollow member 151a of the cylindrical member 151, a spring 157 for energizing the piston 156 to the base end side of the cylindrical member 151 and a cap member 159 for pressing the chuck piece 153 and the spacer 155 from the tip side to the base end side by connecting them through a rod 158 extended to the axial direction to the piston 156.

[0006] The piston 156 is arranged to move to the tip side by supplying compressed air to the hollow part 151a and to move to the base end side by the energization power of the spring 157 by releasing the compressed air.

[0007] The cap member 159 is arranged to move with the piston 156, and the chuck piece 153 and the spacer 155 are pulled to the tip side when the cap member 59 is moving to the tip side and are pressed them to the base end side when the cap member 159 is moving to the base end side.

[0008] The chuck piece 153 is arranged to get on a taper 161 respectively formed in the tip part of the cap member 159 and the spacer 155 by pressing to the base end side, to move to the radial direction and to grip the bobbin 152 by contacting strongly to the inside surface of the bobbin 152.

[0009] However, the gap between the chuck piece 153 and the bobbin 152 is small as the chuck piece 153 cannot move more than the thickness of the spacer 155 having the taper 161, so that the package cannot be occasionally detached from the bobbin holder 150 smoothly when the inside diameter of the bobbin 152 becomes narrower by so-called overwinding in forming the package (not shown in the drawing) by rewinding yarn to the bobbin 152.

[0010] Moreover, as the high velocity rotation of the bobbin 152 is required for improving productivity in recent years, the critical speed of the bobbin holder 150 needs to be increased.

[0011] A critical speed Nc of the bobbin holder 150 can be expressed in the following formula when the outside diameter of the cylindrical member 151 is (D) and the inside diameter of it is (d). Additionally, (B) is a proportionality constant determined by the vertical elastic coefficient, the gravity and the length of the cylindrical member.

[0012] It goes without saying that according to the above formula, the critical speed Nc of the bobbin holder 150 can be increased as the outside or inside diameter of the cylindrical member 151 is larger.

[0013] However, there were problems that it is not preferable in terms of the intensity that the thickness of the cylindrical member 151 becomes thinner as the inside diameter (d) of the cylindrical member 151 becomes larger and that the outside diameter (D) cannot be larger as the thickness of the chuck piece 153 is too thick as the outside diameter (D) becomes larger.

[0014] It is an object of the present invention to solve the above problems and to provide the bobbin holder the critical speed of which is high resulting in a high speed rotation of the bobbin.

[0015] It is another object of the present invention to provide a bobbin holder from which an accomplished package can be detached smoothly.

Summary of the Invention

[0016] For solving the above problems, the present invention comprises a cylindrical member for inserting a bobbin, a plurality of retention rings for inserting into the cylindrical member slidably to the axial direction, a curved or bending laminated chuck piece disposed between the adjacent retention rings so as to swell to the radial direction by compressing to the axial direction and an extendable drive unit extended the chuck piece to the axial direction through the retention ring and provided in the cylindrical member.

[0017] The bobbin is gripped by curving and bending the laminated chuck piece to the radial direction. A spacer limits the swell of the chuck piece to the radial direction if there is no bobbin, so that the outside diameter (D) and the inside diameter (d) of the cylindrical member can be easily formed bigger and the high velocity rotation is available as the chuck piece and the spacer need not to be formed thick. Moreover, a package can be detached smoothly if generating some overwindings in the accomplished package on the bobbin holder as the gap between the chuck piece and the bobbin can be set large.

[0018] Also, it is preferable that the spacer whose both ends are retained to the retention ring with a play of only the predetermined distance to the axial direction limits the interval between the retention rings to the interval between the first interval and the second interval which is smaller than this first interval.

[0019] The chuck piece cannot be too compressed more than requires as the spacer limits the interval between the retention rings to the first interval when releasing the bobbin by the chuck piece on the laminated plate compressing to the center, so that the phenomenon can be prevented from generating that a part of the chuck piece is swelled by pushing to the pushing direction when the package is pushed out from the bobbin holder.

[0020] Moreover, the retention ring has a toric engaging groove on an inner wall, the chuck piece has a first engaging projection fitting along the peripheral direction of the engaging groove in the both ends, the spacer has a second engaging projection fitting along the peripheral direction of the engaging groove in the both ends and it is preferable that the width of the second engaging projection is narrower than the width of the first engaging projection.

[0021] The interval between the adjacent retention rings can be limited to the first interval and the second interval which is smaller than the first interval when the second engaging projection of the spacer is fitted into the engaging groove to the width direction with some space, and the chuck piece can be swelled or compressed properly to the inside and outside of the radial direction within the confined range of this spacer.

Brief Description of the Drawings

[0022] 

Figure 1 is a side view of a substantial part of a bobbin holder illustrating a preferred embodiment of the present invention.

Figure 2 is a cross sectional view of a retention ring.

Figure 3A is a perspective view of a chuck piece, and Figure 3B is a side vew of the chuck piece.

Figure 4A is a perspective view of a spacer, and Figure 4B is a sideview of the spacer.

Figure 5 is an extended elevation illustrating the retention state to a retention ring of the chuck piece and the spacer, and Figure 5A illustrates an extended state and Figure 5B illustrates a compressed state.

Figure 6 is a perspective view of the chuck piece illustrating the other preferred embodiment of the present invention.

Figure 7 is a perspective view of the retention ring illustrating the other embodiment of the present invention.

Figure 8 is a side view of the bobbin holder.

Figure 9 is also a perspective view of the chuck piece illustrating the other embodiment of the present invention.

Figure 10 is a side view of Figure 9.

Figure 11 is also a perspective view of the chuck piece illustrating the other embodiment of the present invention.

Figure 12 is also a perspective view of the chuck piece illustrating the other embodiment of the present invention.

Figure 13 is a side view of the substantial part of the conventional bobbin holder.

Detailed Description of the preferred Embodiments

[0023] A preferred embodiment of the present invention will be described in detail with reference to the drawings.

[0024] As illustrated in Figure 8, a bobbin holder 1 comprises a tubed retention member 3 whose one end can be installed in a machine body 2 such as a melt spinning yarn winder, a rotating shaft 7 which is pivoted rotatably through bearings 4, 5 in the retention member 3 and makes a tip part 6 projected from the retention member 3, a cylindrical member 9 provided in the tip part 6 of the rotating shaft 7 as one for inserting a bobbin B and a bobbin chuck mechanism 10 for fixing the bobbin B into the cylindrical member 9 removably.

[0025] An air passage 12 for supplying air into an after-mentioned hollow part 11 is formed in the rotating shaft 7.

[0026] The almost central part of the longitudinal direction in the cylindrical member 9 is fixed in the tip part 6 of the rotating shaft 7, and the power to the bending direction is not arranged to activate in the tip part 6 of the rotating shaft 7. The cylindrical member 9 is arranged to cover the periphery of the retention member 3 in the base end side.

[0027] As illustrated in Figure 1, the bobbin chuck mechanism 10 comprises the cylindrical member 9 for inserting the bobbin B through after-mentioned retention rings 14a, 14b, the retention rings 14a, 14b for retaining the end of an after-mentioned chuck piece 13 by inserting into the cylindrical member 9 slidably to the axial direction, the curved laminated chuck piece 13 retained between the adjacent retention rings 14a, 14b and disposed in a peripheral part 15 of the cylindrical member 9 so as to swell to the radial direction by compressing to the axial direction, a spacer 50 disposed in parallel with the chuck piece 13 and retained with a play to the axial direction between the adjacent retention rings 14a, 14b and an extendable drive unit 16 provided in the cylindrical member 9 for extending the chuck piece 13 to the axial direction.

[0028] A plurality of the chuck pieces 13, disposed to the peripheral direction and also connected to the axial direction through the retention rings 14a, 14b, can grip a plurality of the bobbins B in the periphery of the cylindrical member 9.

[0029] A plurality of the spacers 50 is disposed so as to alternate to the peripheral direction with the chuck piece 13 and also connected to the axial direction through the retention rings 14a, 14b.

[0030] As illustrated in Figure 8, the edge of the base end side in the chuck piece 13 and the spacer 50 located in the most base end side is retained by an end ring 17 fixed in the back end (the edge of the base end side) in the cylindrical member 9. Moreover, a tip ring 27 fixed in the tip of the cylindrical member 9 retains the edge of the tip side in the chuck piece 13 and the spacer 50 located in the most tip side.

[0031] As illustrated in Figure 3, the chuck piece 13 comprises a metal laminated plate formed longer to the axial direction. In the drawings, three chuck elements 13a one of which is I-shaped are installed consecutively to the peripheral direction as one for the convenience of the molding and assembly. The number of the consecutively installed chuck elements 13a is optional, more than two or four.

[0032] This chuck piece 13 has engaging projections 18, 18 whose width is constant which extend to the peripheral direction so as to engage in the retention rings 14a, 14b in the both ends of the axial direction. As clearly illustrated in Figure 3B, the both ends part including these engaging projections 18, 18, bent in the appropriate points (two points in the drawings) and fitted into an after-mentioned engaging groove 20 of the retention rings 14a, 14b, can follow on the periphery of the cylindrical member 9. The respective chuck elements 13a of the chuck piece 13, curved slightly so that a central part 19 to the axial direction swells to the radial direction, swells the central part 19 to the radial direction in compressing to the axial direction.

[0033] As illustrated in Figure 4, the spacer 50 is composed of the metal laminated plate formed longer to the axial direction. In the drawings, one spacer 50 is I-shaped. This spacer 50 is disposed equally to the peripheral direction of the retention rings 14a, 14b by alternating the spacer 50 and the aforementioned chuck piece 13.

[0034] The spacer 50, having the similar shape as the one chuck element 13a, has an engaging projection 51 whose width is constant extended to the peripheral direction so as to engage in the retention rings 14a, 14b in the both ends of a central part 52. As clearly illustrated in Figure 4B, the both end parts including these engaging projections 51, 51, are bent in the appropriate parts (two parts in the drawings) and can follow the after-mentioned engaging groove 20 of the retention rings 14a, 14b. The central part 52 has the thickness enough to transfer the axial force without bending the bridging or pulling between the retention ring 14a and the retention ring 14b, so that the thickness of the central part 52 of the spacer 50 is thicker than the thickness of the central part 19 of the chuck piece 13.

[0035] As illustrated in Figure 2, the retention rings 14a, 14b has the engaging groove 20 for fitting the engaging projection 18 of the chuck piece 13 and the engaging projection 51 of the spacer 50 in the both ends to the axial direction. The engaging groove 20 is toric. Notches 55 to the radial direction fitting the central part 19 of the chuck piece 13 and the central part 52 of the spacer 50 are provided at regular intervals to the circumferential direction in this engaging groove 20.

[0036] The engaging groove 20 and the notch 55 can fit the engaging projection 18 of the chuck piece 13 and the engaging projection 51 of the spacer 50 into the retention rings 14a, 14b from the inside to the radial direction. This fitted structure retains the chuck piece 13 and the spacer 50 between the adjacent retention rings 14a, 14b on the periphery of the cylindrical member 9.

[0037] Additionally, the end ring 17 and the tip ring 27 as illustrated in Figure 8 have the engaging groove 20 and the notch 55 same as the ones in Figure 2 in the edge facing the center respectively to the axial direction.

[0038] Back to Figure 2, a width (W1) of the engaging projection 18 of the chuck piece 13 is slightly wider than a width (H) of the engaging groove 20 and is fittable. Meanwhile, a width (W2) of the engaging projection 51 of the spacer 50 is narrower than the width (W1) of the engaging projection 18 of the chuck piece 13 and the difference is (δ), so that the spacer 50 limits the interval between the adjacent retention rings 14a, 14b to the interval between a first interval (L) and a second interval which is by (2 × δ) smaller than the first interval (L), namely, (L - 2 × δ).

[0039] As illstrated in Figure 1, the extendable drive unit 16 is composed of a spring 21 for compressing the chuck piece 13 to the axial direction and an air cylinder 22 for extending the chuck piece 13 to the axial direction in the teeth of the energization power of the spring 21.

[0040] The air cylinder 22 comprises the cylinder member 9 forming the hollow part 11 for storing compressed air in the inside, a piston 23 provided slidably to the axial direction in the cylindrical member 9, a rod 24 provided with the piston 23 and extended to the tip side and a guide member 25 provided as one in the cylindrical member 9 for supporting the middle of the rod 24 slidably to the axial direction.

[0041] The rod 24 is arranged to connect to the chuck piece 13 through a cap 26 extended to the radial direction by filling the tip of the cylindrical member 9.

[0042] The cap 26 is engaged with the cylindrical member 9 slidably to the axial direction with spline and arranged not to rotate to the cylindrical member 9. Moreover, the cap 26 has the notch (not shown in the drawings) for engaging the engaging projection 18 of the chuck piece 13 in a tip part.

[0043] The piston 23, blocking off the hollow part 11 for storing compressed air to the axial direction in the tip side of the rotating shaft 7, moves to the tip side by sending compressed air into the hollow part 11.

[0044] The spring 21 is composed of the coil spring displaying the returning power to the compressed power. The spring 21, nipped between the piston 23 and the guide member 25 by inserting the rod 24 in the inside, is arranged to press the piston 23 to the base end side to the axial direction.

[0045] Next, the movements of the bobbin chuck mechanism 10 of the above structure will be described.

[0046] If the bobbin B is set in the bobbin holder 1, the compressed air is supplied from the air passage 12 in the rotating shaft 7 into the hollow part 11. When the air pressure in the hollow part 11 is higher, the piston 23 moves to the tip side in the teeth of the energization power of the spring 21.

[0047] The cap 26 is also moved to the tip side along with the movement of the piston 23 and the chuck piece 13 connected to the cap 26 is pulled to the tip side to the axial direction.

[0048] The chuck piece 13 connected to the cap 26 is drafted with making the swell of the central part 19 to the radial direction smaller and draws the retention ring 14a connected to the base end side and the retention ring 14a pulls the chuck piece 13 connected to the base end side. The chuck piece 13 in the base end side is drafted sequentially and the entire chuck piece 13 is drafted. Then, the interval between the retention rings 14a, 14b is limited to the predetermined first interval (L) by the spacer 50. Therefore, the swell of the central part 19 of the chuck piece 13 is kept in the suitable state so as not to run off the outside diameter of the retention rings 14a, 14b. After that, a plurality of the bobbins B is inserted into the bobbin holder 1 sequentially.

[0049] The bobbin 8 can be inserted into the chuck piece 13 whose central part 19 is deformed flat so as to follow the peripheral surface of the cylindrical member 9.

[0050] As all the bobbins B are inserted into the bobbin holder 1, the bobbin B is fixed in the bobbin holder 1. The bobbin B is fixed by evacuating compressed air from the hollow part 11.

[0051] When the compressed air is evacuated from the hollow part 11, the piston 23 is moved to the base end side by the energization power of the spring 21 and the cap 26 is also moved to the base end side.

[0052] Consequently, the respective chuck pieces 13 connected to the cap 26 is compressed with deforming the central part 19 so as to swell to the radial direction, and is also pressed the retention ring 14a to the base end side through the chuck piece 13.

[0053] The retention ring 14a pressed to the base end side also compresses the respective chuck pieces 13 connected to the base end side of the retention ring 14a and the respective chuck pieces 13 lining to the base end side is compressed sequentially.

[0054] Then, the respective chuck pieces 13 lining to the peripheral direction is compressed at the almost same time and swells the central part 19 to the radial direction as a plurality of the chuck pieces 13 is set out to the peripheral direction.

[0055] The core of the bobbin B is adjusted with being lifted by the chuck piece 13 located in the upper part of the cylindrical member 9 and the inside surface is pressed radially to the chuck piece 13. Then, the inside surface of the engaging projection 18 of the chuck piece 13 is pressed to the cylindrical member 9, so that the bobbin B is fixed to the cylindrical member 9.

[0056] As the rotating shaft 7 for forming the package is rotated, the cylindrical member 9 is also rotated together and the bobbin B fixed in the cylindrical member 9 through the chuck piece 13 is also rotated as one.

[0057] As the package is formed, the piston 23 is moved to the tip side by supplying compressed air into the hollow part 11 again. When extending the respective chuck pieces 13, the package is detached from the bobbin holder 1 by pressing to the tip side.

[0058] Then, as the chuck piece 13 is arranged to retain the bobbin B by swelling the central part 19 adequately though the bobbin B makes the inside diameter smaller by the overwinding, the adequate gap is formed between the chuck piece 13 and the bobbin B by making the chuck piece 13 almost flat by extending and the package can be detached smoothly from the bobbin holder 1.

[0059] Moreover, when the package is pushed to the tip side, the retention rings 14a, 14b in the base end side of the bobbin holder 1 are pushed to the tip side by the friction between the inside diameter of the bobbin B and the retention rings 14a, 14b, and the retention rings 14a, 14b in the tip side of the bobbin holder 1 is occasionally compressed to the direction swelling the chuck piece 13. As illustrated in Figure 5A, however, the interval between the retention rings 14a, 14b in the base end side of the bobbin holder 1 is not too broad as the interval between the retention rings 14a, 14b is limited to the first interval (L) by drafting the central part 52 of the spacer 50, so that the phenomenon can be prevented form generating.

[0060] Further, if the extendable drive unit 16 is driven to the direction that the chuck piece 13 is swelling without inserting the bobbin B into the bobbin holder 1, the chuck piece 13 is occasionally too swelling as there is no regulation to the peripheral direction of the chuck piece 13. As illustrated in Figure 5B, however, the central part 52 of the spacer 50 is bridged and the interval between the retention rings 14a, 14b is limited to the second interval (L - 2 × δ), so that the phenomenon can be prevented from generating.

[0061] The curbed or bending laminated chuck piexe 13 is provided so as to swell to the radial direction by compressing to the axial direction to the peripheral part 15 of the cylindrical member 9 for inserting the bobbin B and the extendable drive unit 16 for extending the chuck piece 13 to the axial direction to the cylindrical member 9 is provided, so that the critical speed can be increased by making the outside diameter (D) and the inside diameter (d) of the cylindrical member 9 easily larger, high speed rotation is available and the package formed on the bobbin holder 1 can be detached smoothly.

[0062] Further, the spacer 50 for limiting the interval between the adjacent retention rings 14a, 14b to the interval between the first interval (L) and the secong interval (L - 2 × δ) is provided for limiting the swell of the chuck piece 13 to the radial direction in parallel with the chuck piece 13, so that the central part 19 of the chuck piece 13 can be prevented from too swelling.

[0063] Consequently, the chuck piece 13 can be prevented from swelling to the extent of the plastic deformation when the extendable drive unit 16 is operated without inserting the bobbin B into the bobbin holder 1.

[0064] Moreover, when the package is pushed out from the bobbin holder 1 to the tip side, the phenomenon can be prevented that the package cannot be pushed out as the interval between the retention rings 14a, 14b is too broad and the chuck piece 13 between the retention ring 14a and the retention ring 14b in the tip side is swelled.

[0065] Further, the thickness of the chuck piece 13 can be thinner to the extent of securing the deformation enough to grip the bobbin and the height of the bobbin chuck mechanism 10 can be totally lower.

[0066] Moreover, as the engaging projection 18 of the chuck piece 13 and the engaging projection 51 of the spacer 50 are fitted into the toric engaging groove 20 of the retention rings 14a, 14b, the intreval between the retention rings 14a, 14b can be limited to the first interval (L) or the second interval (L - 2 × δ) only by narrowing the width of the engaging projection 18 to the engaging groove 20 than the width of the engaging projection 18 of the chuck piece 13. Therefore, the chuck piece 13 and the spacer 50 can be easily and surely fitted into the retention rings 14a, 14b.

[0067] Moreover, as the extendable drive unit 16 comprises the spring 21 for compressing the chuck piece 13 to the axial direction and the air cylinder 22 for extending the chuck piece 13 to the axial direction in the teeth of the energization power of the spring 21, the bobbin B can be stably fixed on the cylindrical member 9 by the energization power of the spring 21 after fixing the bobbin B on the cylindrical member 9.

[0068] The other embodiment of the present invention in changing the chuck piece and the retention ring will be described.

[0069] As illustrated in Figure 6, a chuck piece 61 is formed I-shaped same as the spacer 50. The shape of the chuck piece 61 has engaging projections 62, 62 extended to the peripheral direction in the both ends of a central part 63 curved like a mountain.

[0070] As illustrated in Figure 7, a retention ring 65 has the engaging projection 62 of the chuck piece 61 and an engaging groove 66 for engaging the engaging projection 51 of the spacer 50 in Figure 3 in the both ends to the axial direction. The engaging groove 66 is formed in the inside of the retention ring 65 so as to fit the engaging projection 62 of the chuck piece 61 and the engaging projection 51 of the spacer 50 from the inside to the radial direction. For example, after engaging three of the chuck pieces 61, both are disposed so as to be equal to the peripheral direction as a whole for engaging one spacer 50. Additionally, the positional relation of the width direction of the engaging projection 62 and the engaging projection 51 is same as Figure 5 and Figure 6.

[0071] Further, the other embodiment of the present invention in changing the chuck piece will be described. In addition, the structure other than the chuck piece is same as the above embodiment of the present invention, so that the explanation is omitted.

[0072] As illustrated in Figure 9 and Figure 10, a chuck piece 28, formed laminated and extended to the axial direction, has a bendable joint 29 in the middle to the axial direction.

[0073] The joint 29 rotatably connects a first connecting part 30 forming one end side of the chuck piece 28 and a second connecting part 31 forming the other end side through a pin 32, and the first connecting part 30 and the second connecting part 31 are extended from the position which is eccentric respectively from the shaft of the joint 29 to the axial direction.

[0074] Moreover, a cylindrical engaging shaft 33 extended to the peripheral direction for engaging rotatably to the retention rings 14a, 14b is provided in the both ends to the axial direction of the chuck piece 28 as one.

[0075] To be more precise, the engaging shaft 33 is provided eccentric to the first connecting part 30 and the second connecting part 31 respectively and is arranged to slant the first connecting part 30 and the second connecting part 31 to the joint 29 as illustrated in Figure 10.

[0076] The chuck piece 28 makes the first connecting part 30 and the second connecting part 31 slant to the radial direction toward the joint 29 when provided in the cylindrical member 9 and swell to the radial direction with bending the joint 29 when compressed to the axial direction.

[0077] The bobbin B can be fixed on the bobbin holder 1 when even the chuck piece 28 without the elastic restoring force is compressed or extended to the axial direction on the cylindrical member 9 like this.

[0078] Additionally, the chuck piece 13 comprising the laminated plate which swells the central part 19 to the radial direction and the laminated chuck piece 28 having the bendable joint 29 in the middle to the axial direction are described here, however the embodiment is not confined to this.

[0079] As illustrated in Figure 11, for example, it can be a chuck piece 36 having fold lines 34, 35 in the center to the axial direction and in the vicinity of both ends so as to lift the center to the axial direction.

[0080] In this case, it might be a good idea to form a notch 37 in the both ends of the fold lines 34, 35 in advance so as to be easy to bend in the fold lines 34, 35 in compressing to the axial direction.

[0081] Moreover, as illustrated in Figure 12, it can be a chuck piece 40 with fold lines 38, 39 in a plurality of the positions to the axial direction which is bent in a plurality of the positions, and other shapes are also available if it is the chuck piece which is deformed or bent so as to swell to the radial direction when pressing to the axial direction.

[0082] Moreover, though not shown in the drawings, the spacer 50 is not confined to the laminated shape and it may have a round bar shaped central part between the plates shaped engaging projections in both ends. Moreover, it is preferable that the engaging projection in the both ends of the spacer 50 is also plate shaped, but it may be the round bar shape.

[0083] Moreover, it is preferable that the spacer 50 limits the interval between the retention rings 14a, 14b in the both to the bridging and pulling directions, but it may limit the interval between the retention rings 14a and 14b to at least the bridging direction as it can bridge to the extending direction based on the shape of the chuck piece itself.

[0084] Consequently, the present invention demonstrates the following advantages.

(1) The high velocity rotation of the bobbin holder is available as the bobbin chuck mechanism is formed thinner according to the combination of the chuck piece and the spacer.

(2) The accomplished package can be detached smoothly as the gap between the chuck piece and the bobbin can be set large.

(3) The chuck piece can be prevented from swelling to the radial direction as the spacer limits the interval between the retention rings in compressing the chuck piece to the axial direction when the bobbin is not inserted into the bobbin holder.

Claims

1. A bobbin chuck mechanism of a bobbin holder, comprising:

a curved or bending laminated chuck piece for swelling to the radial direction by compressing the peripheral part of a cylindrical member for inserting a bobbin to the axial direction, and

an extendable drive unit for extending the chuck piece to the axial direction in the teeth of the cylindrical member.

2. A bobbin chuck mechanism of a bobbin holder as in claim 1, wherein the extendable drive unit is equipped with a spring for compressing the chuck piece to the axial direction and an air cylinder for extending the chuck piece to the axial direction to the energization power of the spring.

3. A bobbin chuck mechanism of a bobbin holder as in claim 1 or claim 2, wherein the chuck piece has a bendable joint in the middle to the axial direction.

4. A bobbin chuck mechanism of a bobbin holder, comprising:

a cylindrical member for inserting the bobbin,

a plurality of a retention rings for inserting slidably to the axial direction to the cylindrical member,

a curved or bending laminated chuck piece disposed between the adjacent retention rings for swelling to the radial direction by compressing to the axial direction,

a spacer disposed in parallel with the chuck piece for limiting the interval between the adjacent retention rings in order to limit the swell to the radial direction of the chuck piece, and

an extendable drive unit for extending the chuck piece to the axial direction through the retention ring.

5. A bobbin chuck mechanism of a bobbin holder as in claim 4, wherein the spacer, whose both ends are retained by having a play of only the predetermined distance to the axial direction to the retention ring, limits the interval between the retention rings to the interval between a first interval and a second interval which is narrower than the first interval.

6. A bobbin chuck mechanism of a bobbin holder as in claim 5, wherein the retention ring has a toric engaging groove on the inner wall, the chuck piece has a first engaging projection which fits along the peripheral direction of the groove in the both ends, the spacer has a second engaging projection which fits along the peripheral direction of the groove in the both ends, and the width of the second engaging projection is narrower than the one of the first engaging projection.

Drawing