JP2005238238A - Method and device for manufacturing thin-walled metal tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device for manufacturing a thin-walled metal tube capable of realizing the positional correction by a simple means at low cost even when the position of a welded part is deviated from the position of a butted part. <P>SOLUTION: In the method for manufacturing a thin-walled metal tube by inclining, stretching and rotating an endless belt 21 in a substantially 8-letter shape over a thin-walled metal tape MT which is spirally wound around a supporting member 1 so that ends thereof are butted to each other while the thin-walled metal tape MT is fed in a rotating manner, and characterized in that a butted part mt1 is welded at a predetermined position, the angle of inclination of the endless belt 21 is varied to adjust the positional deviation when the butted part mt1 is deviated from the predetermined position at which the welding is performed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method and apparatus for manufacturing a thin-walled metal tube suitably used for a fixing roller and a photosensitive belt, which are components of an electrostatic recording apparatus (for example, a dry copying machine, a facsimile machine, a printer, etc.). The present invention also relates to a method and an apparatus for manufacturing a thin metal tube by welding a thin metal tape spirally wound around a support member at a fixed position.

  2. Description of the Related Art Conventionally, as an apparatus for manufacturing a cylindrical tube, there is known an apparatus that abuts both ends in a circumferential direction of a curved plate material that has been rounded into a cylindrical shape in advance and jointly welds the abutting portion (for example, see Patent Document 1).

  However, when the cylindrical tube manufactured by the above-described apparatus is used for each component such as the above-described electrostatic recording apparatus, the welding line exists in a straight line along the central axis on the side of the thin metal pipe. By doing so, the internal distortion accompanying welding is concentrated and remains linearly on the side of the thin metal tube.

  For this reason, the thin metal tube does not become a cylindrical body that is uniform in shape and strength in the circumferential direction, and as a result, there is a problem that toner fixing becomes non-uniform.

  Therefore, the applicant of the present invention is to attach an endless belt in the axial direction of the support member so that the thin metal tape is fed out while rotating on the thin metal tape spirally wound around the support member so that the ends meet each other. Inclined, spanned in a shape of approximately 8, and rotated the endless belt, the butted portion formed by abutting the end portions welded in place to produce a thin metal tube Invented the device.

This apparatus will be described in further detail. A thin metal tape that is supported by a bobbin or the like and can be fed out at a winding angle determined by the diameter of a cylindrical support member fixed to a machine frame and the width of the thin metal tape. The end member is wound around the supporting member so that the ends meet each other, and an endless belt made of rubber or the like is formed on the wound thin metal tape in a shape of approximately 8 and with respect to the axial direction of the supporting member. It is tilted and bridged.
Then, by rotating the endless belt, the thin metal tape is fed out while keeping the abutting state between the end portions, and is gradually fed out and moved by a welding portion such as a laser fixed at a fixed position. The butt portion is welded.

  With such a configuration, the manufactured thin metal pipe has a weld line formed in a spiral shape on the side wall of the thin metal pipe. Therefore, even if an internal strain is caused by this welding, the internal strain is generated. However, by being distributed in the circumferential direction of the thin metal tube, it acts to cancel each other, and the roundness of the obtained thin metal tube can be improved.

JP 09-182989 A (first page, FIG. 1)

However, this extremely suitable thin metal pipe manufacturing apparatus invented by the present applicant also has the following points to be improved.
That is, the above-described apparatus welds a butt portion that is gradually drawn out by a weld portion fixed at a fixed position. However, the position of the butt portion is deviated from the weld position of the weld portion. There are cases.

  This is because of the deviation of the attachment angle that occurred when attaching the endless belt, the width of the endless belt (difference from the width of the thin metal tape, the fluctuation caused by the elongation when winding, etc.), the slipping between the endless belt and the support member, etc. It is thought that this is caused by various factors causing the relationship between the pipe making speed and the rotational speed to collapse.

  In order to solve the above-described technical problem, the present inventor studied to correct the welded portion based on the amount of displacement. The technical means for moving the welded portion is technically possible to follow the spiral butting portion that is gradually drawn out and moved, however, its position control becomes extremely complicated. It has been found that the manufacturing cost for realizing the control is too high and cannot be practically adopted.

  Accordingly, the present invention provides a simple means and low cost correction of the position of the welded portion and the butted portion even if the position of the welded portion and the butted portion are misaligned. An object of the present invention is to provide a method and an apparatus for manufacturing a thin metal tube that can be realized in a simple manner.

In order to achieve the above technical problem, the thin metal pipe manufacturing method and apparatus according to the present invention employs the following technical means.
In other words, the thin metal pipe manufacturing method according to claim 1 is flexible so that the thin metal tape is sent out while rotating around the thin metal tape spirally wound around the support member so that the ends meet each other. The endless belt having a property is inclined with respect to the axial direction of the support member and is bridged in a shape of approximately eight, and the endless belt is rotated so that the end portions abut each other. A manufacturing method for manufacturing a thin metal tube by welding at a fixed position, wherein when the butt portion is displaced from the fixed position where welding is performed, the inclination angle of the endless belt is varied to adjust the displacement. It is characterized by performing.
The thin-walled metal pipe manufacturing apparatus according to claim 2 is configured such that the thin-walled metal tape is sent out while rotating on a thin-walled metal tape that is spirally wound around the support member so that the ends meet each other. A flexible endless belt that is slanted with respect to the axial direction and spanned in a substantially 8-character shape, and a butted portion formed by rotating the endless belt and abutting the ends are fixed. And a mechanism part that varies the inclination angle of the endless belt, and when the abutting part is displaced from the fixed position where welding is performed, the endless belt is moved by the mechanism part. The positional deviation adjustment is performed by varying the tilt angle.
The thin metal pipe manufacturing apparatus according to claim 3 is the apparatus according to claim 2, wherein when the butt portion is displaced from the fixed position, the detecting means for detecting a displacement between the fixed position and the butt portion, Control means for adjusting the displacement by operating the mechanism based on detection information from the detection means is provided.

  According to the method for producing a thin metal pipe according to claim 1, the inclination angle of the endless belt is varied to change the pipe making speed (the length per unit time for pipe making by gradually welding the thin metal tape), The abutting part moves with the pipe forming speed, so when the abutting part is displaced from the fixed position where welding is performed, the inclination angle of the endless belt is moved so that the abutting part moves in the direction opposite to the position deviation direction. By simply changing the position, it is possible to easily correct the position of the welded portion and the butt portion.

  According to the thin-walled metal pipe manufacturing apparatus according to claims 2 and 3, for example, a frame that supports an endless belt is supported by a simple mechanism such as a ball screw feed mechanism so as to be swingable, and as described above, welding is performed. When the abutting part is displaced from the position of the part, the inclination angle of the endless belt can be changed so that the abutting part moves in the direction opposite to the misalignment direction, so that a thin metal tube with a position correction mechanism is manufactured. The device can be provided at low cost.

  Next, an embodiment of a thin metal tube manufacturing apparatus and method according to the present invention will be described with reference to the accompanying drawings.

  First, as shown in FIG. 1, the thin metal tube manufacturing apparatus according to the present embodiment includes a support member 1, an endless belt portion 2, a welding portion 3, a detection portion 4, and a control portion 5. Composed.

  The support member 1 is a cylindrical shaft member having a required diameter having a desired thin metal tube diameter (inner diameter), and is fixedly supported by a machine frame of the apparatus main body.

  The endless belt portion 2 includes a pulley 22 in an approximately 8 shape so that the thin metal tube is fed while rotating on the thin metal tube formed by winding and welding the thin metal tape MT around the support member 1. An endless belt 21 such as a flexible flat rubber belt that is suspended so as to be inclined with respect to the axial direction of the support member 1, and a known ball screw feeding mechanism (motor drive) linked to the pulley 22. The endless belt 21 can be moved to a desired angle by tilting the endless belt 21.

  The welded portion 3 is configured by a known laser welding apparatus including a processing head 31 that performs welding by emitting a laser beam, and is near the support member 1 base side from the endless belt 21 spanned over the thin metal tape MT. Further, the processing head 31 (laser center) is fixed so as to coincide with the abutting portion mt1 which is an abutting portion between the ends of the thin metal tape MT.

  The detection unit 4 includes a camera 41 having a well-known structure in which an imaging device such as a CCD or MOS type is built, and, similar to the processing head 31 described above, a center portion of an image captured by the camera 41 and a butting portion mt1 Are arranged to match. In addition, the detection part 4 is not limited to this, What is necessary is just a displacement sensor which detects the left-right movement of the edge part of the thin metal tape MT.

  The control unit 5 performs image processing on the image data captured by the camera 41, detects the amount of misalignment between the position of the butt portion mt1 and the processing head 31, and controls the mechanism unit based on the misalignment information. And the inclination angle of the endless belt 21 is adjusted to a desired angle.

  The thin-walled metal pipe manufacturing apparatus configured as described above first has the thin-walled metal tape MT wound around the bobbin B at a winding angle determined by the diameter of the support member 1 and the width of the thin-walled metal tape MT. The end member 21 is wound around the supporting member 1 so that the end portions abut each other, and the endless belt 21 is bridged over the wound thin metal tape MT in a substantially 8-character shape.

  When rotation of the endless belt 21 is started, the thin metal tape MT moves while sliding on the surface of the support member 1. At this time, since the butt portion mt1 is theoretically stayed at one point if the pipe making speed is advanced by one pitch per rotation, the butt portion mt1 is required by the laser irradiation from the fixed processing head 31. The thin metal tape MT is gradually fed out from the bobbin B while being gradually welded and piped at the pipe making speed v.

  However, a shift in the mounting angle caused when the endless belt 21 is mounted, the width of the endless belt 21 (variation due to a difference from the width of the thin metal tape MT, elongation due to winding, etc.), the endless belt 21 and the support member 1 Due to various factors such as slippage, the relationship between the pipe making speed and the rotational speed may be lost, and the center of the machining head 31 and the position of the butt portion mt1 may be displaced.

In order to solve this problem, the inclination angle of the endless belt 21 is changed, and the position of the butt portion mt1 is corrected and moved to the center of the machining head 31.
Hereinafter, the change in the position of the butt portion mt1 by changing the inclination angle of the endless belt 21 will be described in order using mathematical expressions.

First, a method for calculating the winding angle of the thin metal tape MT will be described in detail.
FIG. 2 is an explanatory view schematically showing the entire wound state of the thin metal tape MT, and FIG. 3 is a partially enlarged view of FIG. In the figure, W is the width of the thin metal tape, Rp is the overlap amount (wrap amount), P is the winding pitch, D is the winding shaft diameter (support member diameter D), and θ is the winding angle.
According to FIG.

As shown in FIG. 4, when the portion wound in the order of OAB is viewed, if the portion of the wound AB is folded back to AB ′, BB ′ passes through C and becomes perpendicular to the axis. Since ∠CAB = ∠CAB ′, BC = B′C. Since BC is perpendicular to the axis, it is half the outer circumference of the axis, and BC = πD / 2. Therefore, BB ′ = πD.
Since ∠B'OB = θ,

It becomes.

Thus, if the thin metal tape width W and the shaft diameter D are known, the winding angle can be calculated. Further, the butt portion mt1 is calculated by setting the lap amount to zero. That is, if Rp = 0 is substituted into the above equations (1) to (3),

It becomes. Even at the time of butt, if the thin metal tape width W and the support member diameter D are known, the winding angle can be calculated.

Here is a specific example. When the support member diameter D: 39.84 mm, thin metal tape width W: 80 mm, wrap amount: 0 mm (butting state), the winding angle θ and the winding pitch P are substituted into the equation (5),
cos θ = 80 / (π × 39.84) = 0.639176
θ = Acos (0.639176) = 50.26956 °
Pitch P is substituted into equation (4) and arranged,
P = 80 / sin (50.26956) = 104.0231
It becomes. That is, if the support member diameter D and the thin metal tape MT are changed, the winding angle and the like change.

Next, the position adjustment of the welding position will be described.
First, FIG. 5 is a schematic diagram showing a locus of a butt portion mt1 of a thin metal tube having a radius r. The thin metal tape MT wound at the speed v in the z-axis direction moves while rotating counterclockwise at the rotation speed f. The rotation amount is rotated once when the winding pitch P advances in the z-axis direction. That is, the rotation angle per unit is 2π / P.
The rotation angle θ of FIG. 5 that is moved by L in the z-axis direction after an arbitrary time t seconds from the reference point O

It becomes. So the coordinates of point A are

It becomes. Here, since the cylinder is actually rotating at a rotation speed of 2π / T, after an arbitrary time t seconds, the cylinder is rotated by φ shown in Equation (9). However, T is the time required for the cylinder to make one rotation in the circumferential direction.

  In other words, when the principal axis conversion is performed using φ, (x, y) is converted into a determinant like (x, y) in Expression (10).

If this expression is expanded,

Then, substituting each value and organizing it,

It becomes. Here, if the movement distance L is expressed using the moving speed v of the cylinder, L = vt, and if substituted into the equation (12),

  It becomes. Here, if (X, Y) stays at one point regardless of the time t, the welding trajectory stays at one point. A condition that is irrelevant to t is found if it is differentiated at t to become zero. That means

Than this,

  Here, T is the time required for the thin metal tube to make one rotation in the circumferential direction, and therefore has the following relationship with the circumferential rotation speed f of the thin metal tube.

Substituting equation (17) into equation (16),

It becomes. This indicates that the spiral stays at one point and the position of welding stays at one point when the z-axis is moved at a winding pitch times (P times) the rotational speed f in the circumferential direction of the thin metal tube.

  Here is a specific example. When the support member diameter is 39.84 mm, the thin metal tape width is 80 mm, and the wrap amount is 0 (butting state), the pitch is 104.023 mm. When the pipe making speed v is 50 mm / s, the rotation speed at that time is 0.4807 rps. At this time, in order to increase the pipe making speed to double 100 mm / s and keep the spiral trajectory at a single point, the relationship of equation (18) should be maintained, but the winding pitch is the width of the thin metal tape width W and the axis Since it is fixed from the diameter D, it can be changed by changing the rotational speed to 0.9613 rps, which is doubled.

  Next, a technical basis on which the position of the butt portion mt1 can be corrected and moved to the welding position by changing the inclination angle of the endless belt 21 will be described.

In the pipe making method, the endless belt 21 is wound in the shape of a figure 8 from above the thin metal tape MT wound around the support member 1, and the endless belt 21 is rotated (see FIG. 1). ).
Since the endless belt 21 is wound at a required angle with respect to the axial direction of the support member 1, the force is divided in the circumferential direction and the axial direction. Therefore, the thin metal tube is fed in the axial direction while rotating.

If the relational expression (18) obtained above is satisfied, the spiral trajectory remains at one point. However, the winding angle of the endless belt 21 is shifted, the width of the endless belt 21 (the difference from the width of the thin metal tape MT, Fluctuation due to elongation at the time of winding, etc.), the tube-forming speed per unit time changes due to the slip of the endless belt 21 and the thin metal tube, and the position of the spiral fluctuates.
The position when rotated by 2πD from the fulcrum O, that is, the distance traveled in the z-axis direction when making one round is ideally the pitch obtained by calculation, but the conditions break down due to the above factors, and the welding position moves to the left and right. (See FIG. 6).

  Therefore, the welding position is controlled, and the first conceivable control means is an ideal movement, that is, the relationship of equation (18), by adjusting v. To actually adjust only v, it can be changed by adjusting the winding speed of the endless belt 21 to be sent out, but at the same time, the sending speed f changes proportionally, and the relationship of equation (18) is satisfied. Don't be. In addition, it is difficult to control the width of the endless belt 21 and the slippage.

  Therefore, by adjusting the winding angle of the endless belt 21 as needed, if the winding angle is changed while the winding speed of the endless belt 21 is kept constant, the winding pitch of the endless belt 21 changes and the pipe making speed (the distance traveled per unit time). ) Changes, the change in the width of the endless belt 21 and the shift due to the friction between the thin metal tape MT and the endless belt 21 are alleviated so that the relationship of Expression (18) is obtained.

  Specifically, the detection unit 4 or the displacement sensor described above is provided at the position of FIGS. 1 and 7 to detect the left and right movement of the end portion of the thin metal tape MT. When the end of the thin metal tape MT in FIG. 7 moves to the left and right, this means that the relationship of equation (18) is broken. Therefore, when the winding angle (tilt angle) of the endless belt 21 is changed according to the change amount, the ratio of the feed amount and the rotation amount in the circumferential direction changes, and the spiral locus passes through one point.

  For example, if the winding angle of the endless belt 21 is decreased by 0.01 degree when moved to the right by 5 μm per second, the winding angle is changed by increasing the winding angle by 0.01 degree when moved to the left by 5 μm. Thus, the ratio of the feed amount and the rotation amount is changed (see FIG. 8). By this control, the difference in the width of the endless belt 21 and the effects of elongation and slipping are alleviated, and the relationship of equation (18) is maintained.

  The advantage of the control of changing the winding angle of the endless belt 21 is that the relationship of the expression (18) can be maintained only by changing the winding angle by alleviating the influence of elongation and slippage of the endless belt 21. That is.

  As described above, the technical basis that the position of the butt portion mt1 can be corrected and moved to the welding position by changing the inclination angle of the endless belt 21 has been described. Based on this, the thin metal tube of the present embodiment A specific example of position correction in the manufacturing apparatus will be described.

This series of correction operations will be described with reference to FIGS.
First, the position data (positional deviation) of the position of the butt portion mt1, that is, the position of the boundary portion between the thin metal tapes MT, with the image data captured by the camera 41 as the origin by a known image processing technique. Amount) is extracted (S1).
Note that when the above formula (18), that is, the relationship of V ≠ P · f from the relationship of V = P · f, the pipe forming speed (the distance traveled per unit time) changes for some reason, A shift occurs, and the butt portion mt1 moves in either the left or right direction without stopping at the center of the image.

  Then, it is determined whether or not the extracted position data (position displacement amount) is displaced from the image center (processing head 31 center) (S2). If it is determined that there is no position shift (S2, No), the process returns to S1 to extract position data.

  If it is determined that a displacement has occurred (S2, Yes: see FIGS. 9 (2) and 9 (3)), the extracted position data (position displacement amount) and mechanical data of the pulley support mechanism (for example, one pulse) The correction control data to be transmitted to the mechanism unit is generated based on the angle change amount of the pulley 22 per signal (S3).

And the control part 5 drives a mechanism part based on this correction control data, and carries out correction | amendment movement of the pulley 22 (S4).
The correction operation at this time is as follows. First, the butt portion mt1 that has moved away from the processing head 31 (image center) is moved toward the center of the processing head 31 by changing the inclination angle of the endless belt 21 based on the data described above. Moving. Even in this series of states, the camera 41 continuously performs imaging / image processing, and determines whether or not the position correction is completed (S5). If it is determined that the position correction is not completed (S5, No), the movement is continued.

  If it is determined that the butt portion mt1 is positioned at the center of the machining head 31 and the position correction is completed (S5, Yes), the angle of the pulley 22 is maintained and the passing trajectory of the butt portion mt1 is stopped, and a series of processing ends. .

The welding portion 3 continues welding even when performing this correction movement, and this correction movement starts immediately when it is determined that even a slight deviation has occurred in the welding position (welding center position). The operation is within a range where no welding failure occurs even if welding is continuously performed. In addition, what was illustrated in FIG. 9 is exaggerated for understanding the contents of the invention, and actually, as described above, even if a slight deviation occurs even in a range where no welding failure occurs. Corrective action is performed.
If the width of the endless belt 21 is different from the width of the thin metal tape MT, the winding pitch of the endless belt 21 is different from the winding pitch of the thin metal tape MT. Therefore, it is easier to control the width of the endless belt 21 closer to the same width as that of the thin metal tape MT.

  The above-described embodiment shows an example of a preferred embodiment of the present invention, and the present invention is not limited thereto, and various modifications can be made without departing from the scope of the invention. .

  For example, the operator can correct the position without automating the above-described correction operation using the detection unit 4 or the control unit 5. Also, a thin metal pipe manufacturing method in which the positional deviation is adjusted by changing the inclination angle of the endless belt 21 may be used.

It is a schematic diagram of the thin metal pipe manufacturing apparatus concerning this Embodiment. It is explanatory drawing which shows the winding state of a thin metal tape. FIG. 3 is a partially enlarged view of FIG. 2. It is a schematic diagram corresponding to the calculation formula of a winding angle. It is a schematic diagram which shows a welding locus | trajectory. It is the schematic diagram which showed the change of the welding position. It is the schematic diagram which showed the attachment position of the displacement sensor. It is the schematic diagram which showed the variation | change_quantity by a winding angle. It is a schematic diagram which shows the example of an image around a butt | matching part. It is a flowchart which shows a series of flows of correction | amendment operation | movement.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support member 2 Endless belt part 21 Endless belt 22 Pulley 3 Welding part 31 Processing head 4 Detection part 41 Camera 5 Control part B Bobbin MT Thin metal tape mt1 Butting part

Claims (3)

  A flexible endless belt is attached to the thin metal tape spirally wound around the support member so that the ends meet each other with respect to the axial direction of the support member so that the thin metal tape is fed out while rotating. A manufacturing method for manufacturing a thin metal tube by inclining and spanning in an approximately eight shape, rotating the endless belt, and welding the butted parts formed by abutting the end parts at a fixed position The method of manufacturing a thin metal tube, wherein when the butted portion is displaced from the fixed position where welding is performed, the displacement is adjusted by changing an inclination angle of the endless belt. The thin metal tape spirally wound around the support member so that the ends meet each other is inclined with respect to the axial direction of the support member so that the thin metal tape is fed out while rotating, and is approximately 8 characters. An endless belt having flexibility in the form of a bridge;
A welded portion that welds in a fixed position a butted portion formed by rotating the endless belt and abutting the ends;
A mechanism for varying the inclination angle of the endless belt;
With
An apparatus for producing a thin metal tube, wherein when the butted portion is displaced from the fixed position where welding is performed, the mechanism portion is configured to adjust the displacement by changing the inclination angle of the endless belt. Detecting means for detecting a positional deviation between the fixed position and the butting portion;
And a control unit configured to adjust the displacement by operating the mechanism unit based on detection information from the detection unit when the abutting unit is displaced from the fixed position. 2. The apparatus for producing a thin metal tube according to 2.