JP2005238327A - Laser marking device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser marking device capable of changing the beam diameter of a beam expander at a low cost and with high accuracy. <P>SOLUTION: In a beam expander 50, a second lens holder 52 is concentrically and tightly fitted to a fitting hole part 51A formed in a first lens holder 51. A tapered surface 61C of an adjustment block 61 is abutted on a tapered surface 52A formed on an incident end face of the second lens holder 52. The adjustment block 61 is moved in the direction orthogonal to the optical axis LC1 by the screw-advancing/screw-retracting a screw hole 61D to/from the screw shaft 62C by turning the screw shaft 62C screwed in the screw hole 61D of the adjustment block 61 clockwise or counterclockwise, and the second lens holder 52 is moved in the direction along the optical axis LC1. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a laser marking device.

  As a laser marking device employing a galvano scanning method, a laser oscillation unit including a laser light source and a beam expander that expands a beam diameter (including a beam width and a beam divergence angle) of laser light from the laser light source, and specifically, Includes a galvanometer mirror device, a scanning unit including an optical system that irradiates a laser beam from a beam expander to a predetermined printing position, which includes a galvanometer mirror device and an fθ lens that condenses the laser beam from the galvanometer mirror device, There is known a connecting means for connecting the scanning unit and these are arranged in a line.

In the laser marking apparatus having the above-described configuration, the connecting means is held so as to be rotatable with respect to the laser oscillation unit or the scanning unit, whereby the scanning unit is rotatable with respect to the laser oscillation unit.
For example, it is used when marking information is printed on the lateral surface of the workpiece flowing on the line. A laser marking device is arranged on the side of the line, and the scanning unit is rotated with respect to the laser oscillation unit to thereby emit laser light. Is emitted parallel to the line, so that marking information can be printed on the lateral surface of the workpiece (see Patent Document 1 and Patent Document 2).
JP 2000-71088 A JP-A-7-116869

  By the way, there is a reality that the spot diameter and work distance of the laser light focused on the work differ depending on the usage environment for each user. To adjust these, the beam diameter of the laser light emitted from the beam expander is changed. A mechanism for changing is provided.

  For example, in the above-mentioned patent document, a screw cut formed on the inner periphery of a first lens holder that houses a collimator lens and a screw cut formed on the outer periphery of a second lens holder that contains a diverging lens are screwed together, There is a mechanism for adjusting the distance between the two lenses by rotating the second lens holder in both forward and reverse directions, thereby changing the beam diameter.

  As a problem of this mechanism, the second lens holder moves finely in the direction perpendicular to the optical axis with respect to the first lens holder unless the threading formation accuracy is high, so the optical axes of both lenses coincide. It becomes difficult to make it. Moreover, it is difficult to secure a desired yield because high accuracy is required, and it cannot be denied that the cost is increased.

In addition, there is a mechanism for changing the distance between both lenses by placing both lens holders on a stage that moves on a linear motion rail and moving these stages along the rail. In practice, a drive unit is provided on the stage, and the stage is moved in both forward and backward directions on the linear motion rail by an external control signal.
This mechanism has the disadvantage that the cost of accuracy management increases as the number of parts by the drive unit increases, resulting in high costs.

One of the most important items in manufacturing is that the optical axis of the laser light from the laser light source, the optical axis of the beam expander, and the rotation axis of the connecting means are matched. If this is slowed down, the laser beam is not accurately irradiated to a predetermined printing position, and as a result, the printing quality is deteriorated. Therefore, it is inevitable that the above adjustment is strictly performed.
However, in the above configuration, since the three elements must be matched, the error factor increases accordingly, and it is difficult to perform adjustment with high accuracy, and the adjustment work also requires enormous time. After all, there is a drawback that defects are likely to occur in terms of manufacturing cost and accuracy. In addition, since the laser light source, the beam expander, and the connecting means are arranged in a line, the marking device becomes long and there is a possibility that the installation space may be restricted.

  The present invention has been completed based on the above situation, and provides a laser marking device capable of changing the beam diameter of laser light emitted from a beam expander with low cost and high accuracy. With the goal.

As a means for achieving the above object, the invention of claim 1 changes the beam diameter of the laser beam from the laser light source through the beam expander, and the laser beam is placed on the print area by the optical system. In the laser marking device that prints marking information such as characters, symbols, and figures by condensing and scanning, the beam expander includes at least two lenses and accommodates one lens. A first lens holder and a second lens holder for housing the other lens;
Guide means for supporting at least one of the first or second lens holders by moving at least one of the lens holders so as to be relatively movable along the optical axis direction;
An adjustment unit having an adjustment block, and linearly displacing the adjustment block in a direction intersecting the optical axis direction;
A tapered surface provided on at least one of the one lens holder side and the adjustment block for moving the lens holder along the optical axis direction based on the displacement of the adjustment block;
The one lens holder includes a biasing unit that biases the adjustment block and the tapered surface in a direction in close contact with each other along the optical axis direction.

The invention according to claim 2 is the taper according to claim 1, wherein the one lens holder is inclined by a predetermined angle with respect to the optical axis around an end surface on the incident or exit side of the laser beam. Forming the surface,
The adjustment block is characterized in that an adjustment taper surface that contacts at least a taper surface of the one lens holder at a position sandwiching the optical axis is formed.

The invention of claim 3 is the one according to claim 2, wherein the tapered surface is formed by inclining the entire end face on the incident or exit side by a predetermined angle with respect to the optical axis,
The adjustment taper surface is characterized in that a passage hole is formed in a region through which the optical axis passes and that the adjustment taper surface can be brought into contact with the entire outer peripheral region of the optical axis.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the guide means is centered on the optical axis formed on one of the first and second lens holders. It is characterized in that the other lens holder is coaxially fitted to the fitting hole.

  The invention according to claim 5 is characterized in that, in the apparatus according to any one of claims 1 to 4, an adjustment amount display means for displaying the adjustment amount of the adjustment means is provided.

  According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the adjusting means includes a shaft portion that rotates to displace the adjusting block, and the adjustment amount display means is configured to rotate the shaft portion. It is characterized in that it has a speed reduction mechanism that converts it into a reduced rotational motion.

According to a seventh aspect of the present invention, in the apparatus according to any one of the first to fifth aspects, the adjusting means includes a shaft portion that rotates to displace the adjusting block, and the shaft portion is the light beam. A screw shaft provided in a direction perpendicular to the shaft;
The adjustment block is formed with a screw hole to be screwed with the screw shaft,
It is characterized in that the adjustment block is screwed back and forth by rotating the screw shaft.

  The invention according to an eighth aspect is the one according to the seventh aspect, wherein the beam expander covers an incident side dustproof portion that covers a portion of the incident side excluding a passing portion through which the laser beam passes, and an emission side. A dustproof cover including an emission side dustproof portion is provided, and the screw shaft is rotatably supported by the incident side dustproof portion.

The invention of claim 9 is the laser oscillation unit according to claim 7 or 8, wherein at least the laser light source is accommodated,
A scanning unit containing at least the optical system;
A connecting means for connecting the laser oscillation unit and the scanning unit, and having an accommodating portion for accommodating the beam expander;
The scanning unit is configured to be held rotatably with respect to the laser oscillation unit about an axis in the connecting direction of the connecting means,
The coupling means is fixed to the laser oscillation unit so that the optical axis and the optical axis of the laser beam are positioned so as to coincide with each other.

  According to a tenth aspect of the present invention, in the apparatus according to the seventh or ninth aspect, the connecting means is fixed so as not to rotate with respect to the laser oscillation unit, and rotates with respect to the scanning unit. It is characterized by being held possible.

  According to an eleventh aspect of the present invention, in any one of the first to tenth aspects, the driving of the galvano scanner is controlled based on marking data for printing including a plurality of coordinate data generated from the marking information. Control means for scanning the laser beam at a predetermined printing position, and a correction signal corresponding to the variation in the distance between the two lenses of the beam expander or the amount of change in the movement of the adjustment block. Signal output means for outputting to the control means, wherein the control means stores reference marking data serving as a reference for printing, and the control means uses the coordinate data constituting the reference marking data. When generating a plurality of coordinate data of the marking data for printing, the level of the correction signal from the signal output means Depending having characterized in that to generate the correction markings data by correcting the coordinate data of the reference marking data.

  According to a twelfth aspect of the present invention, in the eleventh aspect of the present invention, the control means further comprises correction coefficient storage means for storing a plurality of correction coefficient data corresponding to the levels of the plurality of correction signals, and the control means is the control means. According to the level of the correction signal, the corresponding correction coefficient data is read from the correction coefficient storage means, and the coordinate data of the reference marking data is corrected based on the read correction coefficient data.

  According to a thirteenth aspect of the present invention, in the method according to the eleventh or twelfth aspect, the reference marking data includes line type data in each line segment generated from the marking information, and start and end positions of the line type data. Primary data composed of the coordinate data of the primary data, and the primary data is converted into a plurality of coordinate data including the start point and the end point at predetermined intervals based on the line type data of the primary data. The printing data is converted into secondary data which is marking data, and the control means scans the laser beam based on the secondary data, and the control means generates the secondary data for the correction. It is characterized in that it is performed on the coordinate data of the primary data in the previous stage.

  In the present invention, since the lens holder is moved by so-called linear motion conversion, the beam diameter can be changed with a simple structure, and the optical axis shift can be prevented (invention of claim 1). .

  Further, an adjustment taper surface is formed on the adjustment block while the entire incident or emission side is inclined with a predetermined angle with respect to the optical axis, and the adjustment taper surface is sandwiched between the optical surfaces of the taper surfaces. If it is configured to abut against the entire position or the outer peripheral region of the optical axis, it is possible to prevent the optical axis shift more reliably (invention of claim 2 or claim 3).

  If the guide means is formed on one of the lens holders and the other lens holder is coaxially fitted to the fitting hole with the optical axis as the center, both guide holders are assembled at the assembly stage. The optical axes of the lenses can be made to coincide with each other, and the accuracy can be ensured at a much lower cost than that using a conventional screw cutting (invention of claim 4).

  If the adjustment amount display means for displaying the adjustment amount of the adjustment means is provided, a guideline for determining the adjustment amount of the adjustment means can be easily made (invention of claim 5).

  If the adjustment means has a shaft portion that rotates to displace the adjustment block, and the adjustment amount display means has a speed reduction mechanism that converts the rotational motion of the shaft portion into a reduced rotational motion, the adjustment means can be adjusted. The amount can be accurately displayed (invention of claim 6).

  The adjustment means has a shaft portion that is rotated to displace the adjustment block, the shaft portion has a screw shaft provided in a direction orthogonal to the optical axis, and the adjustment block has a screw that is screwed with the screw shaft. If the hole is formed and the adjustment block is screwed back and forth by rotating the screw shaft, the spatial range of the adjustment operation accompanying the movement of the adjustment block can be minimized (invention of claim 7). .

  Moreover, if the screw shaft is configured to be rotatably supported by the dust cover, a dedicated member for supporting the screw shaft is not required, so the number of parts can be reduced, and further, the screw shaft can prevent dust. Since the cover is hermetically sealed, the dustproof performance can be reliably maintained (invention of claim 8).

In addition, since the connecting means is provided with a housing portion and the beam expander is housed in the housing portion, the center axis in the connecting direction of the connecting means is aligned with the optical axis of the beam expander. The error factor at the time of axis adjustment can be reduced, so that the accuracy of optical axis adjustment can be improved, and the adjustment can be further facilitated. In addition, the manufacturing cost can be reduced by greatly reducing the labor required for adjustment.
Furthermore, by accommodating the beam expander in the connecting means, the apparatus can be shortened (invention of claim 9).
Further, since only the scanning unit is configured to rotate, for example, stress generated in the coupling unit is reduced as compared with a configuration in which the coupling unit and the scanning unit are rotated with respect to the laser oscillation unit. The durability can be improved (the invention of claim 10).

  According to the invention of claim 11, since the marking data is corrected based on the correction signal from the signal output means, the size of the printed character or figure is always constant regardless of the adjustment of the focal length of the optical system. It becomes.

  According to the twelfth aspect of the present invention, the reference marking data is corrected based on a correction coefficient corresponding to the magnitude of the correction signal. With such a correction format, the accuracy of correction is higher than when correction is performed based on a single correction coefficient (the printed characters are close to the desired character size).

  According to the thirteenth aspect of the present invention, the correction of the marking data is performed on the coordinate data of the primary data before the secondary data is generated. If it is such a correction timing, when secondary data is generated (secondary data represents marking information only by coordinate data, so the number of coordinate data that needs to be corrected, that is, the number of coordinate data) Compared to the primary data), the correction process is less and the processing is also faster.

<Embodiment 1>
A laser marking apparatus according to a first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the laser marking device includes an oscillation unit 10 having a laser light source 14, a head unit 20 having an optical member such as a galvano mirror device 24 and a converging lens (for example, an fθ lens 25), 20 includes a connecting member 30 that connects 20, a beam expander 50 accommodated in the connecting member 30, and an adjustment mechanism 60 that adjusts the beam expander.

<Oscillation unit>
The housing 11 of the oscillation unit 10 has a cylindrical shape with a substantially rectangular cross section, and includes a vertically long base portion 12 having wall portions on the front and rear sides and a cover portion 13 having a plate surface suspended from the left and right side portions of the top plate. It consists of parts.
The housing 11 is provided with a laser light source 14 for emitting laser light. For example, the head 11 is formed of a CO2 laser light source and is formed from a circular laser emission port 15 formed in the wall portion 12A on the front side of the base portion 12. Laser light that is invisible light is emitted to the unit 20. Further, a plate-like base member 12A is provided on the bottom surface of the base portion 12, and the laser light source 14 is placed on the adjustment block 16 stacked thereon.
Between the laser light source 14 and the wall portion 12A, a cover portion 17 having a U-shaped cross section (corresponding to the incident-side dustproof portion) is formed upright from the bottom surface, and of these, the wall portion 18 parallel to the wall portion 12A. Is provided with a passage hole H (φ = 5 mm) for passing the laser beam (corresponding to the passage portion), the emission end face of the housing of the laser light source 14 is in contact with the wall portion 18, and The laser light from the laser light source 14 is positioned so as to pass through the passage hole H. Further, a screw hole portion 19A in which two screw holes having different diameters are formed coaxially is formed in the wall portion 19 orthogonal to the wall portion 12A.

<Head unit>
The housing 21 of the head unit 20 has a cylindrical shape with a substantially rectangular cross section like the oscillation unit 10, and includes a base portion 22 having a wall portion 22A at the rear end, a plate surface suspended from the left and right sides of the top plate, and the front end. The cover part 23 has two parts. In addition, the inside of the scanning unit 20 is hermetically sealed by these two components, and exhibits a dustproof function (corresponding to the emission side dustproof portion).
The housing 21 is provided with a galvanometer mirror device 24, an fθ lens 25, and the like, and the laser light incident inside through a circular laser incident port 26 formed in the wall surface 22A on the rear side of the base portion 22 is galvanized. The direction is changed via the mirror device 24, and the light is converged by the fθ lens 25 and irradiated onto the print area of the work (not shown). The irradiation position of the laser beam is determined by the rotation angle of the galvanometer mirrors 24A and 24B provided in the galvanometer mirror device 24, and the galvanometer mirrors 24A and 24B are rotated based on the marking information such as desired characters, symbols and figures. By operating, the marking light is printed by scanning the converging light on the printing area.
The fθ lens 25 is threaded at the peripheral portion, is formed in the base portion 22, and is screwed into a hole portion that is threaded at the inner peripheral edge.

<Connecting member>
The connecting member 30 is formed around a cylindrical connecting portion 31 that bridges between the laser emitting port 15 of the oscillation unit 10 and the laser incident port 26 of the head unit 20, and is formed around the cylindrical connecting portion 31. It is comprised from the fixing | fixed part 40 which fixes 20 integrally.

The cylindrical connecting portion 31 is disposed on the inner side of the oscillation unit 10 with respect to the laser emission port 15, and extends vertically from the inner ring portion of the annular base portion 32 and enters the laser incident port 26. And a cylindrical portion 33 (corresponding to the “accommodating portion” of the present invention). The annular base portion 32 has an inner ring diameter smaller than the laser emission port 15 by the thickness of the cylindrical portion 33, and the outer ring diameter is conversely larger. A plurality of screw holes 34 are formed in the circumferential direction of the annular base portion 32, and the side surface portion is fixed to the oscillation unit 11 by being screwed to the wall surface 12 </ b> A of the oscillation unit 11. The outer diameter of the cylindrical portion 33 is substantially the same as the diameters of the laser emission port 15 and the laser incident port 26, so that the cylindrical portion 33 is tightly fitted to the oscillation unit 10 and the head unit 20. Yes. A small diameter portion and a large diameter portion are formed on the inner periphery of the cylindrical portion 33 with a step portion 35 formed on the laser incident port 26 side as a boundary. When a beam expander 50 described later is accommodated. The housing 51 of the beam expander 50 has a function of engaging with the step portion 35 to help prevent the shift in the connecting direction.
Further, the cylindrical portion 33 is provided with a portion that is thin along the axial direction, and a hole portion 32 </ b> A is formed in a portion of the annular base portion 32 that corresponds to the thin portion.

  The fixed portion 40 includes a first annular projecting portion 41 formed to project from the periphery of the laser emission port 15 toward the head unit 20 on the wall surface 12A of the oscillation unit 10, and a periphery of the laser incident port 26 on the wall surface 22A of the head unit 20. The second annular projecting portion 42 formed projecting from the oscillating unit 10 toward the oscillation unit 10 and the annular projecting portions 41 and 42 are brought into contact with each other, and are swaged (caulked) over the entire circumferential direction. It comprises a crimping ring 43 that fixes the head unit 20 so as not to be relatively displaced.

  The first annular projecting portion 41 has a square cross-sectional shape with an acute angle, and the outer annular portion of the first annular projecting portion 41 is formed with an annular slope portion 41A that rises in an overhanging manner with respect to the wall surface 12A, An upright annular wall surface 41B is formed in the inner ring portion. Further, an annular flat portion 41C parallel to the wall surface 12A is formed between the outer ring portion and the inner ring portion.

  The second annular protrusion 42 has a square cross-sectional shape with an acute angle similar to the first annular protrusion 41, and the outer ring portion of the second annular protrusion 42 stands in an overhang shape with respect to the wall surface 26. A slope portion 42A is formed, and an upright cylindrical wall portion 42B is formed in the inner ring portion. An annular flat surface portion 42C parallel to the wall surface 22A is formed between the outer periphery of the cylindrical wall portion 42B and the outer ring portion.

  The annular flat surface portion 41C of the first annular protrusion 41 and the annular flat surface portion 42C of the second annular protrusion 42 are in contact with each other with the inner ring diameter and the outer ring diameter being matched with each other. A part of the cylindrical wall portion 42B of the second annular flat surface portion 42 enters the inside of the annular wall surface portion 41B of the portion 41.

  The caulking ring 43 has an end ring shape, and an inner ring portion is formed with a V-shaped recess 43A, and each of the annular inclined surface portions 41A of the first and second annular projecting portions 41, 42 is formed in the recess 43A. , 42A enters. In addition, bolt holes are formed at both ends (not shown), and by bolting, the entire circumference of the first and second annular protrusions 41 and 42 can be crimped radially inward. It can be done.

  A tubular resin 44 is interposed between the wall tubular portion 42 </ b> B of the second annular projecting portion 42 and the tubular coupling portion 31. The cylindrical resin 44 functions like a bearing, and thereby, the wall cylindrical portion 42C and the cylindrical connecting portion 31 are smoothly and relatively moved in the circumferential direction.

<Beam expander>
The beam expander 50 includes a collimator lens 53, a diverging lens 54, and a spring portion 55 in a cylindrical housing.
The housing includes a first lens holder 51 that accommodates the collimator lens 53 and a second lens holder 52 that accommodates the diverging lens 54, and is formed on the oscillation unit 10 side of the first lens holder 51. The second lens holder 52 is coaxially fitted in the fitting hole 51A. Further, the first lens holder 51 is accommodated in the cylindrical connecting portion 31 so that the central axis C in the connecting direction of the cylindrical connecting portion 31 coincides with the optical axis LC of the beam expander 50. Is positioned.
Further, a cavity A is formed between the thin portion of the cylindrical portion 33 and the first lens holder 51, and the oscillation unit 10 and the head unit 20 are electrically connected by wiring an electric wire in the cavity A. Can be connected to.

The first lens unit 51 has a cylindrical shape, and a step portion 51B is formed on the outer peripheral surface of the first lens unit 51 on the head unit 20 side, and this step portion 51B is associated with the step portion 35 of the cylindrical connecting portion 31. Stop. Further, a step portion 51C is also formed on the inner peripheral surface, and an end of the spring portion 55 is addressed to the step portion 51C. Further, the collimator lens 53 accommodated in the first lens holder 51 is disposed on the end surface side on the head unit 20 side, and the lid 51 is closed from the end surface so that the stepped portion 51D of the first lens holder 51 and the lid are covered. 51E is sandwiched by 51E and cannot move.
A circular for passing an adjustment block 61 (which will be described later) constituting the adjustment mechanism 60 for adjusting the position of the second lens holder 52 to the oscillation unit 10 side of the first lens holder 51. Through holes 51F are formed and arranged inside the oscillation unit 10.

  The second lens holder 52 has a cylindrical shape like the first lens holder 51, and has an outer diameter that is substantially the same as the diameter of the fitting hole 51A described above so as to be in a close fitting state. (Corresponding to the “guide means” of the present invention). Among these, the end surface on the oscillation unit 10 side is formed with a tapered surface 52A that is inclined as a whole, and a tapered surface 61B of an adjustment block 61 described later comes into contact therewith.

  The spring portion 55 (biasing means) is formed of a so-called coil spring, and is disposed between the step portion 51C and the second lens holder 52 described above. Since the spring portion 55 is in contact with the step portion 51C, the elastic force is applied to the second lens holder 52, and the spring portion 55 is moved to move to the oscillation unit 10 side.

<Adjustment mechanism>
The adjustment mechanism 60 (corresponding to the adjustment means) includes an adjustment block 61, a shaft portion 62 that supports the adjustment block 61, and a support portion 63 that supports the shaft portion 62 on the wall portion 12C.
The support portion 63 has a two-stage cylindrical shape with different diameters in which bolt members 63A and 63B having different diameters are arranged coaxially, and a through hole 63C through which the shaft portion 62 is passed is formed in the central axis. Among these, two hole parts 63D are formed on the end face of the large-diameter bolt member 63A so as to be symmetric with respect to the central axis. The support portion 63 is screwed into a screw hole portion 19A provided in the wall portion.

The shaft portion 62 has a cylindrical shape, a linear groove 62A is formed on the base end surface, and a large diameter portion 62B is formed at a position from the front end side as viewed from the base end surface. On the other hand, a threaded shaft 62C is formed on the distal end side, and a pin hole is provided on the base end side of the shaft 62C at a right angle with respect to the extending direction of the shaft portion 62. This pin hole is adapted to fit the lock pin 65 together with the hole provided in the ring 64 passed through the shaft portion 62, whereby the ring 64 is fixed to the shaft portion 62. The distance between the large diameter portion 62B and the pin hole is substantially the same as the dimension in the direction along the central axis direction of the support portion 63.
A cylindrical resin J is interposed between the shaft portion 62 and the through hole 63 </ b> C of the support portion 63. This has a function of a bearing, and the shaft portion 62 is idled.

The adjustment block 61 has a shape in which a cylinder standing upright from the disc-shaped base end portion 61A is cut obliquely, and a tapered surface 61B (adjustment taper surface) is provided in the cut-out portion. . The tapered surface 61B is in contact with the entire outer peripheral region of the optical axis LC in the tapered surface 52A of the second lens holder 52 described above. Further, a passage hole 61C is formed so as to surround the optical axis LC1 in the adjustment block 61, and has an elliptical shape that is long in the left-right direction.
A screw hole 61D is formed from the base end portion 61A to the through hole 61C side, and the above-described screw shaft 62C is screwed together. Thus, by rotating the shaft portion 62, the adjustment block 61 can be moved in the left-right direction (direction perpendicular to the optical axis).

<Adjustment amount display device>
The adjustment amount display device 90 (corresponding to the adjustment amount display means) includes a housing 92 that also serves as a display plate, and an indicator 91 that is pivotally supported by the housing 92. The indicator 91 meshes with a small-diameter gear 62D that rotates together with the shaft portion 62 at both ends of a shaft portion 91A that is rotatably attached to the housing 92 via a bearing 93, thereby rotating the screw shaft 62C. A large-diameter gear 91B that decelerates and transmits it to the indicator 91 and an instruction plate 91C on which an instruction arrow (shown in FIG. 9) is formed are provided. A reduction mechanism is configured by the small diameter gear 62D and the indicator 91, and the number of teeth of the small diameter gear 62D and the large diameter gear 91B is set so that the small diameter gear 62D rotates a plurality of times while the large diameter gear 91B makes one rotation. Has been.

  On the other hand, a scale DG indicating the adjustment amount of the adjustment mechanism 60 is printed on the lower surface of the housing 92 in FIG. 7 (shown in FIG. 9). In addition, the shaft portion 62 also passes through the housing 92 so as to be rotatable through a bearing (not indicated). When the shaft portion 62 and the screw shaft 62C are rotated, the indicator plate 91C of the indicator 91 is rotated after being decelerated via the small diameter gear 62D and the large diameter gear 91B. Indicates the scale DG, and the adjustment amount of the adjustment mechanism 60 is displayed. The scale DG on the housing 92 in this embodiment displays the standard work distance of the laser marking device as 0, and displays the amount of increase / decrease relative thereto. When the indicator 91 decelerated by the deceleration mechanism indicates the scale DG, even if the screw shaft 62C rotates and adjusts more than one rotation, the adjustment amount can be displayed accurately. is there.

The configuration of the laser marking device of the present embodiment is as described above, and the operation thereof will be described.
First, the cylindrical connecting portion 31 is passed from the inside of the oscillation unit 10 through the laser emission port 15 to screw the annular base 32, and the cylindrical resin 44 is passed through the outer ring portion of the cylindrical connecting portion 31. Subsequently, after the beam expander 50 is accommodated in the cylindrical connecting cylinder portion 31, the cylindrical portion 33 is caused to enter the laser incident port 26 of the head unit 20. Then, since the first annular protrusion 41 and the second annular protrusion 42 come into contact with each other, the caulking ring 44 is attached and screwed. As a result, the positioning is performed in a state where the central axis C of the cylindrical connecting portion 31 and the optical axis LC of the beam expander 50 coincide.

  Next, in order to make the optical axis LC1 of the laser light emitted from the laser light source 14 coincide with the optical axis LC of the beam expander 50, the adjustment block 16 is stacked on the base member 12B. The number of adjustment blocks 16 to be stacked may be preliminarily stacked in advance, and then the apparatus may be actually operated to make fine adjustments. Alternatively, the apparatus may be operated and the result may be used. The number may be adjusted.

By the way, when it is desired to adjust the spot diameter or work distance of the laser beam condensed on the work, the adjustment block is moved in the left-right direction (direction orthogonal to (intersects) the optical axis LC1), and the first and first The diameter of the laser light emitted from the beam expander 50 (including the beam width and the beam divergence angle) is changed by adjusting the separation distance between the two lens holders 51 and 52 in the optical axis LC1 direction. Just do it.
For example, when narrowing the beam diameter of the laser light, an instrument is applied to the groove portion 62A of the shaft portion 62, and the shaft portion 62 is rotated, for example, counterclockwise. Then, since the screw hole 61D is screwed out with respect to the screw shaft 62C, the fitting depth of the second lens holder 52 into the fitting hole 51A increases as the tapered surface 61B is displaced to the left. (Linear motion conversion). Thereby, since the distance between both lenses 53 and 54 is reduced, the beam diameter can be reduced (see FIG. 10).
On the other hand, when enlarging the beam diameter of the laser beam, an instrument is applied to the groove portion 62A of the shaft portion 62 and the shaft portion 62 is rotated in the clockwise direction. Then, since the screw hole 61D is screwed with respect to the screw shaft 62C, the fitting depth of the second lens holder 52 into the fitting hole 51A is reduced as the tapered surface 61B is displaced to the right. (Linear motion conversion). Thereby, since the distance between both lenses 53 and 54 is expanded, a beam diameter can be expanded (refer FIG. 11). When the shaft portion 62 is rotated, the adjustment amount can be grasped by the scale DG indicated by the instruction arrow on the instruction plate 91C.
When the above operation is completed, the cover portions 13 and 23 of the oscillation unit 10 and the head unit 20 are covered.

  Further, in order to change the position of the laser emission port of the head unit 20, the screw of the caulking ring 44 is loosened and the head unit 20 is rotated. When the rotation operation is performed, the head unit 20 is rotated with respect to the central axis C of the cylindrical connecting portion 31. Therefore, the caulking ring 44 may be screwed to the desired position. Thereby, the head unit 20 is fixed to a predetermined posture.

In the present embodiment, since both lens holders 51 and 52 are moved by so-called linear motion conversion, it is possible to change the beam diameter with a simple structure and prevent optical axis deviation. Further, since the entire end surface on the incident side is an inclined surface inclined by a predetermined angle with respect to the optical axis LC1 as the tapered surface 52A, the optical axis shift can be prevented more reliably.
In addition, since the second lens holder 52 is coaxially fitted in the fitting hole 51A formed in the first lens holder 51, the optical axes of both lenses can be matched in the assembly stage. In addition, the accuracy can be ensured at a much lower cost than those using conventional screw cutting.

  Since the adjustment amount display device 90 that displays the adjustment amount of the adjustment mechanism 60 is provided, a guideline for determining the adjustment amount of the adjustment mechanism 60 can be easily obtained.

  Since the adjustment block 60 is provided on the screw shaft 62C in the direction orthogonal to the optical axis LC1, and the adjustment block 60 is screwed back and forth by the rotation of the screw shaft 62C, the spatial adjustment operation accompanying the movement of the adjustment block 60 The range can be minimized.

Further, when the screw shaft 62C rotates, the adjustment block 61 is screwed back and forth, and the adjustment amount display mechanism 90 converts the rotational motion of the screw shaft 62C into a rotational motion that is decelerated, and the speed reduction mechanism 62D, Since the scale DG for displaying the rotation amount 91 is provided, the adjustment amount of the adjustment mechanism 60 can be accurately displayed.
Further, since the shaft portion 62 is rotatably supported by the cover portion 19, a dedicated member for supporting the shaft portion 62 is not necessary, and the number of parts can be reduced. Furthermore, since the screw hole portion 19A is sealed by the support portion 63, the dustproof performance can be reliably maintained. Note that the diameter (φ) of the through hole H is a very small hole of about 5 mm and is closed by the emission end face of the laser light source 14, so that it does not cause deterioration of the dustproof performance.

Since the beam expander 50 is accommodated in the cylindrical connecting portion 31, the center axis C in the connecting direction of the cylindrical connecting portion 31 and the optical axis LC of the beam expander 50 are positioned so as to coincide with each other. An error factor at the time of adjustment is reduced, so that the accuracy of optical axis adjustment can be improved and the adjustment can be further facilitated. In addition, the labor required for adjustment is greatly reduced, and the manufacturing cost can be reduced.
Further, since the beam expander 50 is accommodated in the cylindrical connecting portion 31, the apparatus can be shortened.
Further, since only the head unit 20 is configured to rotate, for example, the cylindrical connection unit 31 is compared with a configuration in which the cylindrical connection unit 31 and the head unit 20 are rotated with respect to the oscillation unit 10. Therefore, the durability can be improved.

<Embodiment 2>
In the second embodiment, as shown in FIG. 12, a tapered surface 70 </ b> A is provided on a plate member 70 extending toward the direction perpendicular to the optical axis LC <b> 1 on the incident end surface side of the outer peripheral surface of the second lens holder 52. The taper surface 61B of the adjustment block is brought into contact with the taper surface 70A, which is different from the first embodiment. Even if configured in this manner, linear motion conversion is performed as in the above-described embodiment.

<Embodiment 3>
In the third embodiment, the tapered surface 61B of the adjustment block 61 is brought into contact with the portion of the tapered surface 52A formed on the incident end surface of the second lens holder 52 as shown in FIG. It has been configured.

<Embodiment 4>
In the fourth embodiment, as shown in FIG. 14, a U-shaped passage groove 80 is formed along the direction orthogonal to the optical axis LC1 from the distal end side to the proximal end side of the adjustment block 60. The laser beam is configured to pass through the passage groove 80.

<Embodiment 5>
In the fifth embodiment, as shown in FIG. 15A, the adjustment block is formed in a cylindrical shape, and as shown in FIG. 15B, the second lens holder 52 is formed in a cylindrical shape. It is configured to do. Even in this case, the second lens holder 52 can be moved along the optical axis direction.

<Embodiment 6>
Embodiment 6 will be described with reference to FIGS. 16 to 21. FIG.
Reference numeral 110 shown in FIG. 16 denotes a control unit (corresponding to the control means of the present invention). The control unit 110 includes a CPU 111 and a reference marking data storage unit 115. The control unit 110 stores an operation panel 160 for inputting marking information via a signal line, and font data such as characters, symbols, and figures. The font data storage unit 130 is connected.
Further, the laser light source 14, the beam expander 50, the galvano device 24, and the Fθ lens 25 have the same configuration as that of the first embodiment.

  When the marking information is input from the operation panel 160, the control unit 110 generates printing marking data (details will be described later) based on the marking information and the font data, and the galvano based on the generated printing marking data. The apparatus (corresponding to the galvano scanner of the present invention) 24 is driven to print predetermined marking information on the print position on the workpiece W.

  Further, as already described in the first embodiment, the beam expander 50 is provided with the adjustment block 61. For example, when the thickness of the workpiece W is different from the set value, the adjustment block 61 is prior to the printing operation. The relative distance between the first and second lens holders 51 and 52 is changed by moving the lens in the direction crossing the optical axis LC, thereby adjusting the work distance (adjusting the focal length of the optical system according to the work). ) (See FIGS. 17 and 18).

  However, when such work distance adjustment is performed, if the adjusted focal length L1 is shorter than the reference focal length Lo as shown in FIG. 17, the size of characters printed on the workpiece W is set in advance. Compared to the reference character size (character size when the focal length is Lo), it becomes smaller in proportion to the focal length variation ratio (L1 / Lo), and the adjusted focal length L2 is smaller than the focal length Lo. If the length is longer, the character size becomes larger in proportion to the fluctuation ratio (L2 / Lo). This is because the drive control of the galvano device 24 by the control unit 110 is based on the focal length Lo.

Therefore, in this embodiment, the beam expander 50 is provided with a detection unit (corresponding to the signal output means of the present invention) 150, and reference marking data (described later) based on the correction signal S output from the detection unit 150. The data (corresponding to the focal length Lo) is corrected with respect to the size of characters, figures, symbols and the like.
Here, the correction means that the character, figure, and symbol size of the marking information printed on the work W is constant regardless of the adjustment of the focal length of the optical system (work distance adjustment). The correction is to correct the variation of the character, symbol, and figure size accompanying the adjustment.

As shown in FIG. 18, the detection unit 150 is disposed in front of the adjustment block 61 in the forward / backward direction (upward in the figure). The detection unit 150 is configured by a position detection sensor. In the present embodiment, the position detection sensor employs a proximity sensor, but may be of a photoelectric type or a capacitance type.
If the adjustment block 61 is moved forward / backward to adjust the work distance prior to the printing operation, the detecting unit 150 detects the forward / backward movement and responds to the displacement amount (displacement amount from the initial position) of the adjustment block 61. A correction signal S having a predetermined magnitude is output to the CPU 111. In the CPU 111, the correction signal S is temporarily stored.
FIG. 18 shows a state in which the adjustment block 61 is lowered from the reference position (position shown in FIG. 7).

  Next, font data, reference marking data, correction of reference marking data, and marking data for printing will be described.

  The font data is composed of line type data and coordinate data of the start point and end point of the line type data (see FIG. 19). For example, in the case of font data of the character A, three line type data each including S1s and S1e, S2s and S2e, and S3s and S3e are provided. In the case of a set of S1s and S1e, first, the line type indicates a straight line (uppercase S), and S1s indicates the start point of the line segment and the end point is S1e.

  S1s corresponds to the coordinate data b1 (Xf1, Yf1), and S1s corresponds to the coordinate data b2 (Xf2, Yf2). Thereby, the line S1 of the three line segments constituting the font data A is specified. Further, the line S2 is specified by the set of S2s and S2e, and the line S3 is specified by the set of S3s and S3e. Note that the coordinate of each font data is such that the point Z is the reference point (0, 0).

When an input signal related to marking information is sent from the operation panel 160, the CPU 111 reads the corresponding font data from the font data storage unit 130 and assigns it to the print area L to generate reference marking data (primary data). (See Step 1 in FIG. 20). More specifically, the assignment of font data is to convert the coordinates of the read font data into coordinate values on the print area L. In FIG. 20, the character A is read out as font data. In this case, the coordinates of the reference point Z are replaced from (0, 0) to (m, n), similar to the replacement of the coordinates of the reference point Z. Is replaced in each of the coordinate data b1 to b5.
For example, the coordinates of the point b1 in the reference marking data are (X1, Y1), which is obtained by adding (m, n) to the coordinates (Xf1, Yf1) of the point b1 in the font data (X1 = Xf1 + m). Y1 = Yf1 + n).

When the reference marking data is generated as described above, the CPU 111 temporarily stores the reference marking data in the reference marking data storage unit 115.
Thereafter, when the correction signal S from the detection unit 150 described above is stored, the CPU 111 corrects the reference marking data to generate corrected marking data. More specifically, the CPU 111 is connected to a correction coefficient storage unit 140 (corresponding to the correction coefficient storage means of the present invention) 140 via a signal line. The correction coefficient storage unit 140 stores a plurality of correction coefficients (β1, β2,... Βn) as shown in FIG.

The correction factor β is calculated from the test results by changing the work distance adjustment amount (adjustment block displacement amount) and measuring the character size enlargement / reduction ratio for each adjustment amount. It has been done. For example, if the character reduction ratio was 0.9 at a certain adjustment amount, to restore this to the original character size, a correction was made to increase the character size by the amount that the character was reduced. Since it is only necessary to do so, the value of the correction coefficient β is 1.1.
Each correction coefficient β is associated with the level of the correction signal S. When the correction signal S is input to the CPU 111, the CPU 111 reads out the correction coefficient βn corresponding to the input correction signal Sn from the correction coefficient storage unit 140. It is like that. For example, if the level of the correction signal S is S1, the correction signal β1 is read out.

  Thereafter, the CPU 111 converts coordinate data constituting the reference marking data based on the correction coefficient β1, and generates corrected marking data. For example, in the case of coordinate data of b1, (X1, Y1) is corrected to (X1 ', Y1') (see Table 1). The correction of the reference marking data with the correction coefficient β is to adjust the enlargement / reduction ratio of the character and does not involve any change of the line type, so no change is made to the line type data.

Next, the marking data for printing (secondary data) will be described. In the corrected marking data (reference marking data), the assigned font data is represented by line type data and coordinate data. It is represented by a plurality of coordinate data including the start point and end point of the line segment (only coordinate data). Specifically, it is obtained by extracting each point (coordinate data) on the line segment at a predetermined interval (in this embodiment, a pitch that is half the spot diameter of the laser beam) (see STEP 2 in FIG. 20).
If the work distance is not adjusted prior to the printing operation (when no correction signal is output), the CPU 111 generates printing marking data based on the reference marking data.

  Thereafter, the CPU 111 drives the galvano device 24 based on the generated marking data for printing. Thereby, predetermined marking information is printed at the printing position on the workpiece W.

As described above, according to this embodiment, when the work distance is adjusted prior to the printing operation, the detection unit 150 detects this and outputs the correction signal S to the CPU 111. On the other hand, when the correction signal S is input to the CPU 111, the correction signal S is temporarily stored, and after the reference marking data is generated, the correction coefficient β corresponding to the level of the correction signal S is read from the correction coefficient storage unit 140. To generate correction marking data.
As a result, the corrected marking data is corrected to data that matches the focal length L of the optical system after adjustment, so that a desired character, symbol, figure size (reference) set in advance on the workpiece W is obtained. Marking information is printed in (Size).

Further, when correcting the marking data, for example, it is possible to perform the correction on the marking data for printing after the marking data for printing is generated without correcting the reference marking data. In the embodiment, the reference marking data is corrected before the printing marking data is generated. This is because the coordinate data of the reference marking data is the data of the start and end points of the line segment (if the marking information is character A, five data), while the marking data for printing contains the marking information. The number of data is large because it is represented only by coordinate data. Therefore, if the correction is performed on the reference marking data, the correction processing is less than that in the case where the correction is performed on the marking data for printing, so that the processing becomes faster.
In addition, the reference marking data is corrected based on the correction coefficient β corresponding to the magnitude of the correction signal S. With such a correction format, the accuracy of correction is higher than when correction is performed based on a single correction coefficient (a character to be printed is closer to a desired character size).

  In this embodiment, the distance between the collimator lens 53 and the diverging lens 54 is displaced via the adjustment block 61 in order to adjust the work distance. Such adjustment is performed by adjusting the spot diameter of the laser beam. Also done. Therefore, in this case as well, the marking information is printed on the workpiece W with the desired character, figure, and symbol size set in advance regardless of the adjustment of the spot diameter by correcting the reference marking data. Is possible.

<Generation method of marking data>
The laser light from the laser light source is changed through a beam expander including at least two lenses, the beam diameter of the laser light is changed, the changed laser light is condensed on the work by the optical system, and a control means is provided. The laser beam is scanned at a predetermined printing position on the workpiece by controlling the driving of the galvano scanner based on the predetermined marking data for printing, and further, the two means provided in the beam expander by the adjusting means In the marking data generation method of the laser marking device that adjusts the focal length of the laser beam with respect to the workpiece by adjusting the distance between the lenses, the laser marking device includes the two beam expanders. For changing the distance between lenses or moving the adjustment block And a signal output means for outputting a correction signal corresponding to the magnitude of the change amount to the control means, and the marking data for printing is coordinate data of reference marking data corresponding to a reference focal length. On the other hand, correction is performed based on the correction signal, and the correction signal is generated based on the corrected marking data.

If the method of generating the marking data for printing without making any correction to the reference marking data when the focal length L is adjusted, it is almost proportional to the fluctuation ratio of the focal length L. The size of characters, figures, symbols, and the like to be printed fluctuates, resulting in a situation in which marking information is not printed at a desired size.
In this regard, in the above marking data generation method, the reference marking data is corrected based on the correction signal from the signal output means, and the marking data for printing is generated based on the corrected marking data. Therefore, since the generated marking data for printing matches the focal length of the optical system after adjustment, it is effective when printing with a desired character size is desired regardless of the adjustment of the focal length L. In particular, regarding the marking data generation method, in addition to the beam expander 50 in the first embodiment, the adjustment means includes other focal length adjusting means (beam expander 200) in the ninth embodiment to be described later. Adjustment means are also included.

<Embodiment 7>
In the seventh embodiment, the configuration of the detection unit 150 is changed with respect to the sixth embodiment. In the sixth embodiment, the detection unit 150 is configured by a position detection sensor. However, in the seventh embodiment, the detection unit 170 is configured by a potentiometer instead of the position detection sensor. In this case, the interlocking shaft 171 that engages with the potentiometer is provided in the large-diameter gear 91B provided in the indicator 91 (see FIG. 22).
Thus, when the shaft portion 62 is rotated, the rotation operation is transmitted to the potentiometer via the large-diameter gear 91B and the interlocking shaft 171. Therefore, the resistance value of the potentiometer is changed to the shaft portion 62. It changes according to the amount of rotation. Therefore, a correction signal S corresponding to the amount of rotation of the shaft portion 62, that is, the amount of displacement of the adjustment block 61 is output from the detection unit 170 to the CPU 111.
Since other configurations are the same as those in the first embodiment, the same components are denoted by the same reference numerals, and redundant description is omitted.

<Eighth embodiment>
In the eighth embodiment, the configuration of the detection unit 150 is changed from that of the sixth embodiment. In the sixth embodiment, the detection unit 150 is configured by a position detection sensor. However, in the eighth embodiment, the detection unit is configured by a console 180 including a key panel 181. As shown in FIG. 23, an indicator 183 is provided on the console 180, and the adjustment amount of the adjustment block 61 is displayed there. Based on the display of the indicator 183, the operator keys in a predetermined correction value (for example, referring to a manual). Thereby, the correction signal S is output to the CPU 111. Thus, even if it is the structure which inputs a correction value manually, the correction effect similar to Embodiment 6 and Embodiment 7 is acquired.
Since other configurations are the same as those of the sixth embodiment, the same portions are denoted by the same reference numerals, and redundant description is omitted.

<Ninth Embodiment>
In the ninth embodiment, the configuration of the beam expander (focal length adjusting means) is changed from that of the sixth embodiment. In the sixth embodiment, the adjustment block 61 having the tapered surface 61B is displaced in the direction intersecting the optical axis LC, and thereby the distance between the collimator lens 53 and the diverging lens 54 is displaced. In the panda 200, a slide mechanism 210 is attached to the collimator lens 53 (see FIG. 24). The slide mechanism 210 is composed of a pair of rails 211 and 212 that can be relatively moved in the horizontal direction, and a motor M that drives the rails 211 and 212. When an operator turns on a switch (not shown), the motor M is driven. The rail 211, and thus the collimator lens 53 is moved horizontally. As a result, the distance between the collimator lens 53 and the diverging lens 54 can be displaced.

Reference numeral 220 in FIG. 24 denotes a detection unit made up of a proximity sensor, which detects the movement of the collimator lens 53 or the rail 211 and outputs a correction signal S corresponding to the amount of displacement to the CPU 111.
On the other hand, the CPU 111 temporarily stores the output correction signal S. After that, when marking information is input via the operation panel 160, the CPU 111 generates the reference marking data and then generates the same reference signal. The marking data is corrected by the same procedure as that of the sixth embodiment. Thus, the marking information is printed on the workpiece W with a desired character size set in advance, regardless of the adjustment of the focal length of the optical system, as in the case of the sixth embodiment.

That is, the laser light from the laser light source is condensed on the print region through an optical system including at least one optical component, and the focal position of the condensed light is determined by moving the optical component in the optical axis direction. A focal length adjusting means for adjusting; a control means for controlling the driving of the galvano scanner based on predetermined printing marking data to scan the laser beam at a predetermined printing position; and a movement of the optical component in the optical axis direction. A laser marking device comprising a signal output means for detecting and outputting a correction signal corresponding to the amount of movement to the control means,
The control means stores reference marking data as a reference for printing. The reference marking data is line type data in each line segment generated from the marking information, and the coordinates of the start point and end point position of the line type data. The primary data is composed of data, and the primary data is converted to a plurality of coordinate data including the start point and the end point at predetermined intervals based on the line type data of the primary data. It is converted into secondary data which is marking data for use, and the control means scans the laser beam based on the secondary data, and the control means is a step before the secondary data is generated, Correction is performed on the coordinate data of the primary data according to the level of the correction signal.

  When adjusting the work distance (adjusting the focal length), a focal length adjusting means may be provided. In this case, if no correction is made to the reference marking data, the focal length L The size of characters, figures, symbols, and the like to be printed varies substantially in proportion to the fluctuation ratio of the mark, and the marking information cannot be printed with a desired character size.

In this regard, according to the above configuration, the reference marking data is corrected based on the correction signal from the signal output means, and the marking data for printing is generated based on the corrected marking data (corrected marking data). . Therefore, since the generated marking data for printing matches the focal length L of the adjusted optical system, it is effective when printing is desired with a desired character size regardless of the adjustment of the focal length L.
In addition, when marking data is corrected, for example, it is possible to perform correction on the marking data for printing (secondary data) after the marking data for printing is generated without correcting the reference marking data. However, in the above configuration, the reference marking data (primary data) is corrected before the marking data for printing is generated. This is because the coordinate data of the reference marking data is the data of the start and end points of the line segment, whereas the marking data for printing has a large number of data because it represents the marking information only by the coordinate data. Therefore, if the correction is performed on the reference marking data, the correction processing is less than that in the case where the correction is performed on the marking data for printing, so that the processing becomes faster.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.

  (1) In the above embodiment, the configuration in which the tapered end surfaces 52A and 61C are formed on the incident end surface of the second lens holder 52 and the adjustment block 61 is shown, but the tapered surface may be formed only on one of them. Good.

  (2) In addition to the configuration in which the tapered surface 52A is formed on the incident end surface of the second lens holder 52, a tapered surface may be formed on the exit end surface of the lens holder 52.

  (3) For example, the diverging lens 54 may be accommodated in the first lens holder 51 and the collimator lens 53 may be accommodated in the second lens holder 52. In this case, the second lens holder 52 may be configured to be disposed on the head unit 20 side, and the second lens holder 52 may be configured to move relative to the first lens holder.

  (4) In the above embodiment, the cylindrical connecting portion 31 is fixed to the oscillation unit 10 and only the head unit 20 is rotated. For example, the cylindrical connecting portion 31 is connected to the head unit 20. The cylindrical connecting portion 31 and the head unit 20 may be configured to rotate with respect to the oscillation unit 10, or the cylindrical connecting portion 31 may be rotatably attached to both the units 10 and 20. Alternatively, only the head unit 20 may be rotated, or the head unit 20 and the cylindrical connecting portion 31 may be rotated with respect to the oscillation unit 10.

  (5) In the above-described embodiment, the configuration in which the cylindrical connecting portion 31 is provided separately from the oscillation unit 10 and the head unit 20 is shown. However, the head unit 20 rotates with respect to the oscillation unit 10. For example, it may be configured to be formed integrally with either the wall portion 12A of the oscillation unit 10 or the wall portion 22A of the head unit 20 because it may be possible. In short, the “connecting means” of the present invention is a mechanism for connecting the oscillation unit 10 and the head unit 20, and it does not matter whether the unit 10 or 20 is integrated or separate.

  (6) In the above embodiment, the scanning unit 20 is configured to be rotatable with respect to the oscillation unit 10. However, the scanning unit 20 may be configured to be non-rotatable with respect to the oscillation unit 10. Good.

  (7) Moreover, it is good also as a structure which inserted the light transmissive member which permeate | transmits a laser beam (infrared light) in the passage hole H of the said embodiment, for example. In this way, the dustproof performance can be further enhanced.

  (8) The scale DG may represent the amount of rotation of the shaft portion 62 or the screw shaft 62C without providing a reduction mechanism in the adjustment amount display device 90.

  (9) The scale DG of the adjustment amount display device 90 does not indicate the work distance but may indicate the movement amount of the first lens holder 51 or the second lens holder 52 and the distance between the lenses 53 and 54. .

  (10) An indication arrow may be formed on the housing 92, and a scale DG may be formed on the indication plate 91C of the indicator 91.

  (11) For example, a configuration may be adopted in which the convergent lens (collimator lens) 53 is accommodated in the first lens holder 51 and the convergent lens 53 ′ is accommodated in the second lens holder 52. In this case, the first lens holder 51 may be moved relative to the second lens holder 52, or the second lens holder 52 may be moved relative to the first lens holder. You may comprise.

  (12) For example, the first lens holder 51 and the second lens holder 52 may be configured to be movable relative to each other.

Upper side view showing the overall configuration of the laser marking device of the present embodiment Side view showing the overall configuration of the laser marking device Side view showing the internal structure of the head unit Side view when viewing the connecting cylinder from the inside of the head unit Side view when viewing the connecting cylinder from the inside of the oscillation unit AA sectional view showing a connecting cylinder part and its peripheral structure BB sectional view showing the connecting cylinder part and its peripheral structure The perspective view which showed the adjustment mechanism and its peripheral structure Front view of adjustment amount display device AA sectional view showing an adjusting mechanism and its peripheral structure AA sectional view showing an adjusting mechanism and its peripheral structure The figure which showed Embodiment 2 notionally The figure which showed Embodiment 3 notionally The figure which showed Embodiment 4 notionally The figure which showed Embodiment 5 notionally Block diagram of laser marking apparatus in embodiment 6 Diagram showing focus adjustment operation The figure which shows the detection operation by the detection part Figure showing font data Diagram showing standard marking data and marking data for printing The figure which shows that the several correction coefficient is memorize | stored in the correction coefficient memory | storage part The figure which shows the structure of the detection part in Embodiment 7. The figure which shows the structure of the detection part in Embodiment 8. The figure which shows the structure of the beam expander in Embodiment 9. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Oscillation unit 20 ... Head unit 30 ... Connecting member 50 ... Beam expander 51 ... 1st lens holder 52 ... 2nd lens holder 52A ... Tapered surface 55 ... Spring part 61 ... Adjustment block 61C ... Tapered surface 61D ... Screw Hole 62 ... Shaft portion 62C ... Screw shaft 62D ... Small diameter gear 91 ... Indicator 92 ... Housing C ... Center axis of connecting member LC ... Optical axis of beam expander LC1 ... Optical axis of laser light emitted from laser light source DG ... Scale

Claims (13)

By changing the beam diameter of the laser light from the laser light source through the beam expander, and condensing the laser light on the print area by the optical system, and marking the characters, symbols, figures, etc. In a laser marking device that prints information,
The beam expander includes at least two lenses, and includes a first lens holder that accommodates one lens and a second lens holder that accommodates the other lens, and
Guide means for supporting at least one of the first or second lens holders so as to be relatively movable along the optical axis direction by moving the lens holder;
An adjustment unit having an adjustment block, and linearly displacing the adjustment block in a direction intersecting the optical axis direction;
A tapered surface provided on at least one of the one lens holder side and the adjustment block for moving the lens holder along the optical axis direction based on the displacement of the adjustment block;
A laser marking apparatus comprising: an urging unit that urges the one lens holder in a direction in which the adjustment block and the tapered surface are in close contact with each other along the optical axis direction. In the one lens holder, the tapered surface is formed by inclining a predetermined angle with respect to the optical axis around the end surface on the incident or exit side of the laser beam,
2. The laser marking according to claim 1, wherein the adjustment block has an adjustment taper surface that contacts at least a taper surface of the one lens holder at a position sandwiching the optical axis. apparatus. The tapered surface is formed by inclining the entire end surface on the incident or exit side by a predetermined angle with respect to the optical axis,
The adjustment taper surface has a passage hole formed in a region through which the optical axis passes, and is configured to be able to contact the entire outer peripheral region of the optical axis in the taper surface. 2. The laser marking device according to 2. The guide means is configured by coaxially fitting the other lens holder in a fitting hole centered on the optical axis formed in one of the first and second lens holders. The laser marking device according to any one of claims 1 to 3, wherein the laser marking device is provided. 5. The laser marking apparatus according to claim 1, further comprising an adjustment amount display unit that displays an adjustment amount of the adjustment unit. The adjustment means has a shaft portion that is rotated to displace the adjustment block, and the adjustment amount display means has a reduction mechanism that converts the rotation motion of the shaft portion into a reduced rotation motion. The laser marking device according to claim 5. The adjusting means has a shaft portion that is rotated to displace the adjusting block, and the shaft portion has a screw shaft provided in a direction orthogonal to the optical axis,
The adjustment block is formed with a screw hole to be screwed with the screw shaft,
6. The laser marking device according to claim 1, wherein the adjustment block is screwed back and forth by rotating the screw shaft. The beam expander is provided with a dust-proof cover including an incident-side dust-proof portion that covers a portion of the incident side excluding a passage portion through which laser light passes, and an exit-side dust-proof portion that covers the exit side. The laser marking device according to claim 7, wherein the screw shaft is rotatably supported by a dustproof portion. A laser oscillation unit containing at least the laser light source;
A scanning unit containing at least the optical system;
A connecting means for connecting the laser oscillation unit and the scanning unit, and having an accommodating portion for accommodating the beam expander;
The scanning unit is configured to be held rotatably with respect to the laser oscillation unit about an axis in the connecting direction of the connecting means,
9. The structure according to claim 7, wherein the coupling means is fixed to the laser oscillation unit so that the optical axis is aligned with the optical axis of the laser beam. The laser marking device described in 1. 10. The connection unit according to claim 7, wherein the connecting unit is fixed so as not to rotate with respect to the laser oscillation unit and is held so as to be rotatable with respect to the scanning unit. Laser marking device. Control means for controlling the driving of the galvano scanner based on the marking data for printing including a plurality of coordinate data generated from the marking information to scan the laser beam at a predetermined printing position;
Signal output means for outputting to the control means a correction signal corresponding to the variation in the distance between the two lenses provided in the beam expander or the amount of change in movement of the adjustment block;
The control means stores reference marking data serving as a reference for printing, and the control means generates a plurality of coordinate data of the marking data for printing from the coordinate data constituting the reference marking data. The correction marking data is generated by correcting the coordinate data of the reference marking data according to the level of the correction signal from the signal output means. Laser marking device. A correction coefficient storage means for storing a plurality of correction coefficient data corresponding to a plurality of correction signal levels;
The control means reads the corresponding correction coefficient data from the correction coefficient storage means according to the level of the correction signal, and corrects the coordinate data of the reference marking data based on the read correction coefficient data. The laser marking device according to claim 11, wherein The reference marking data consists of primary data composed of line type data in each line segment generated from the marking information, and coordinate data of the start point and end point position of the line type data,
Based on the line type data of the primary data, the primary data is converted into secondary data which is the marking data for printing by converting the data into a plurality of coordinate data including the start point and the end point at predetermined intervals. The control means scans the laser beam based on secondary data,
The marking device according to claim 11 or 12, wherein the control unit performs the correction on the coordinate data of the primary data before the secondary data is generated.

Images