JP2749504B2 - Sheet additive manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for forming a three-dimensional object by bonding and laminating sheets.

[0002]

2. Description of the Related Art Conventionally, as an apparatus for forming a three-dimensional model having a complicated shape, an apparatus for laminating paper sheets coated with a hot-melt adhesive in advance is known. In this apparatus, the sheets are adhered to each other by heating the sheets with a hot roller after laminating each paper sheet. Then, the upper layer paper sheet is cut along the contour of the region constituting the three-dimensional object.

[0003]

However, in the above-described apparatus, it is difficult to form a three-dimensional object with high modeling accuracy by laminating and bonding the sheets with high precision. In addition, there is an apparatus for modeling a three-dimensional object with high accuracy by using a photo-curing molding method. However, since a photo-irradiation step is required using a photo-curing resin, equipment for implementing the above method is prepared. The initial cost is high and the molding surface needs to be cleaned with alcohol. Furthermore, it is difficult to form such a three-dimensional object in a normal office, for example, a secondary curing process is required after molding to obtain a complete polymerization rate.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sheet stacking apparatus capable of forming a three-dimensional object with higher precision and ease in order to solve the above-mentioned problems in the prior art.

[0005]

Means for Solving the Problems As means for solving the above-mentioned problems, the present inventors have developed an apparatus for forming a three-dimensional object by laminating sheets provided with an adhesive . , On
Sheets that can be moved down and to which adhesive has been applied are sequentially supplied.
The mounting table to be fed and stacked, and the lower surface side is the entire surface of the sheet
Pressing surface large enough to press
The sheet is fixed at a predetermined height position above and the sheet is described above.
Pressing against this pressing surface by upward movement of the table
And a bonding means for bonding the sheets to each other via the adhesive, and a cutting edge fixed at a predetermined height position.
Cut the top sheet on the table into an effective area and an unnecessary area.
And a cutting means for cutting the sheet. In addition, the present inventors have created the sheet laminating apparatus, characterized in that an adhesive that exerts an adhesive force when pressed is used as the adhesive. In addition, the present inventors have created the sheet laminating apparatus, wherein the intermediary means supplies the adhesive onto the upper sheet by electrostatic transfer.

The sheet may be any sheet capable of forming a three-dimensional object by adhesive lamination. The adhesive can be appropriately selected depending on the type of the sheet, the method of supplying the adhesive, the strength required for the three-dimensional object to be formed, and the like. The electrostatic transfer means that, after particles are attached to an electrostatic latent image formed on a drum by an electrostatic recording method, an electrophotographic method, a laser recording method, or the like, the particle image is electrostatically placed on a sheet. To move.

[0007]

According to the first aspect of the present invention, the mounting table can be vertically moved.
The entire surface of the sheet is pressed at once by the movement alone. Also glued
Of the mounting table is the only movable part for
Predetermined pressing state for lamination bonding can be obtained only by height control
It is. According to the second aspect of the present invention, since the sheets are adhered to each other by pressure using an adhesive exhibiting an adhesive force by pressure, there is no need for light irradiation or the like. In addition, the adhesive strength can be controlled by the upward movement position of the mounting table. According to the third aspect of the present invention, since the adhesive is supplied by electrostatic transfer, ordinary electrostatic transfer means can be used as the intermediary means for the adhesive.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment embodying the present invention will be described below with reference to FIGS. In this embodiment, the sheet 2 has a thickness of 0.1 mm and a thickness of 297 mm × 420.
mm mm plain paper (high quality paper) is used. It is also possible to use a continuous sheet instead of a single sheet while cutting it. As the adhesive 4, one obtained by removing the pigment from the electronic toner and having a polyethylene-based thermoplastic resin as a main component was used. Note that the electronic toner is usually mainly composed of a thermoplastic resin and a pigment as a binder, and the electronic toner itself can be used as the adhesive of the present invention. Further, an adhesive (toner, for example, a capsule toner for developing an electrostatic latent image described in JP-A-59-189354) which is fixed to the sheet 2 only by applying pressure which does not require heating can be used. . In the case of using an adhesive that can be fixed by pressure, a simple plate is sufficient instead of the heater plate 32 described later, so that the apparatus cost can be reduced, and unmanned modeling can be performed by ensuring higher safety. There are merits such as that it becomes unnecessary.

FIG. 1 shows a sheet additive manufacturing apparatus according to this embodiment. This additive manufacturing apparatus is mainly configured by a data processing unit 8, a control unit 9, and a sheet additive manufacturing unit (hereinafter, simply referred to as a modeling unit) 10.

The data processing unit 8 creates two-dimensional information data representing the cross-sectional shape of the three-dimensional object based on the information representing the shape of the three-dimensional object, and supplies this data to the modeling unit 10. In the present embodiment, the information indicating the shape of the three-dimensional object supplied to the data processing unit 8 is a three-dimensional CA
D is provided by the D system, and the two-dimensional shape information of the cross section is obtained based on the three-dimensional shape information.
It is well known in the field of CAD systems.

The data processing unit 8 converts the two-dimensional shape information supplied from the three-dimensional CAD system into raster data and supplies the raster data to the laser printing unit 18 and the cutting plotter unit 34. The raster data is data representing the cross-sectional shape of the three-dimensional object, and one side of the contour of the cross-sectional shape is an effective area forming the three-dimensional object, and the other side is an unnecessary area. The section vector data and the raster data are created for each sheet 2.

The control section 9 controls the sequence of the laser printer section 18 and the cutting plotter section 34 and controls the height position of the table 14.

The modeling section 10 is composed of a table section 12, a paper feed tray section 16, a laser printer section 18, a transport section 22, a heater plate section 30, and a cutting plotter section 34. The table section 12 has a table 14 for mounting the laminate under modeling and a motor (not shown) capable of moving the table in the vertical direction.
Further, the table unit 12 includes a detecting device (not shown) for detecting the absolute position (height) of the table 14, and the height position is controlled by the control unit 9. Each time one sheet 2 is stacked by the operation of the motor, the table 14 is vertically moved upwardly to a heater plate section 30 described later, and further, the height of the stacked sheets 2 is increased to a predetermined height. Is moved down to the position. Each time the sheets 2 are stacked, the downward movement position is lowered by the thickness of the sheet 2 (more precisely, by the thickness of the sheet 2 and the thickness of the adhesive 4).

The paper feed tray section 16 has a tray 17 on which sheets 2 are stacked and placed, and a motor (not shown) for vertically moving the tray. The paper feed tray section 16 holds sheets 2 that have been cut to a predetermined length in advance, and supplies the sheets 2 to the laser printer section 18 one by one. The laser printer section 18 electrostatically transfers the adhesive 4 onto the sheet 2 and is the same as that used for a general laser printer or copying machine. In the laser printer section 18, an electrostatic latent image is formed on a drum by exposure with a laser beam in accordance with data provided from the data processing section 8, an image of the adhesive 4 is formed, and the adhesive image is further formed. This is to electrostatically transfer onto the sheet 2.
The laser printer unit 18 has a fixing unit 20 for fixing the adhesive 3 transferred onto the sheet 2, and is conveyed by the conveying unit 22 after passing through the fixing unit 20.

As shown in FIG. 1, the transport section 22 includes a chain 24, a sprocket 26, a sheet holding mechanism 27, and a motor (not shown) for driving the sprocket 26. The chain 24, the sprocket 26, and the holding mechanism 27 are provided on both sides of the sheet 2 to be conveyed in the width direction (perpendicular to the conveyance direction). The holding mechanism 27 is provided so as to be able to hold the sheet 2 facing the chains 24 on both sides. The transport unit 22 is controlled by an air conditioner, a fan, and the like to adjust the surrounding humidity environment and the like so that the sheet 2 can be moved from the laser printer unit 18 to the table unit without absorbing moisture.

Further, an intermediate tray section 28 is provided at the leading end side of the transport section 22 for temporarily reversing the sheet 2 and temporarily placing the sheet. The intermediate tray section 28 includes a tray 29a and a jogger 29.
b, and the sheet 2 temporarily placed on the tray 29a is pushed by the jogger 29 from right and left and front and rear, and then supplied to the table unit 12. Further, the intermediate tray section 28 is also a tray for adjusting the operation of the laser printer section 18 and the cutting plotter section 34 by the control section 9.

The heater plate section 30 includes the table section 1
The plate 32 is fixedly arranged at a predetermined height directly above the plate 2 and has a size sufficient to press the entire surface of the laminate T on the lower surface side, and the plate 32 can be heated to a predetermined temperature (not shown). And a heater unit. The table 14 on which the laminate T is placed is lifted from below and pressed against the pressing surface of the plate 32, so that the upper sheet 2Y on the surface of the laminate T and the lower sheet 2X immediately below the laminate 2 adhere to each other. Is done. The heating temperature of the plate 32 is appropriately set according to the type of the sheet 2 and the adhesive 4 to be used, the degree of pressing, and the like. The pressing surface of the plate 32 is subjected to a release treatment using a fluororesin or silicon so that the pressed upper sheet 2Y does not adhere to the lower surface of the laminate T due to the downward movement of the table 14 and is easily peeled off. ing.

The cutting plotter section 34 includes a cutter 3
5 and an XY plotter 36 to which a cutter 35 is fixed and moves horizontally based on data supplied by the data processing unit 8. Cutting plotter section 3
Numeral 4 is provided at a predetermined height below the heater plate section 30 and above the table section 12 and at a location where there is no obstacle to the vertical movement of the table 14 and the feeding of paper onto the table 14. The cutter 35 serving as an action section is configured to two-dimensionally cut only the uppermost sheet 2 of the sheets 2 stacked on the table 14 at a constant height position by the XY plotter 36. It is. That is, cutter 3
The working height of 5 is always constant and does not move up and down.
By controlling the height of the table 14, the cutter 35
Can work.

As the cutting means, a laser cutter, an ultrasonic cutter or the like can be used in addition to the cutter 35. In particular, advantages of using the cutter 35 include that the initial cost can be reduced, that there is no need to arrange dust removal equipment, that there is no risk of fire, and that the cutting depth can be easily controlled.

The modeling part 10 thus formed is housed in a cabinet, and the humidity and the thermal environment around the sheet 2 are controlled. In the present embodiment, an air conditioner (not shown) is provided in the cabinet for accurately managing the heat and humidity generated in the modeling unit 10.

Hereinafter, a process of forming a three-dimensional object using the forming device formed as described above will be described with reference to FIG. FIG. 2 is a process cross-sectional view showing a procedure for forming a three-dimensional object M by laminating the sheets 2 by the present apparatus. First, as the lower sheet 2 constituting the laminate T, the tray 1
7 is supplied to the printer unit 18. The lower sheet 2X is conveyed to the table 14 without transferring the adhesive 4, is set on the table 14, and is cut into an effective area and an unnecessary area by the cutter 35. And
It moves down by the thickness of the lower sheet 2X and waits until the next sheet 2Y is supplied. The lower sheet 2Y is shown as a lower sheet in FIG. 2B.

FIG. 2A shows an upper sheet 2Y to be laminated on the lower sheet 2X on the table 14 and an adhesive layer 40 formed by transferring the adhesive 4 to the surface thereof. ing. The data of the cross-sectional shape of this sheet 2Y is
It is obtained by slicing the three-dimensional object M from the bottom with the thickness of the sheet 2X. The adhesive layer 40 is formed based on the two-dimensional information.

The adhesive layer 40 is formed from an effective adhesive layer 42 and an auxiliary adhesive layer 46. First, three-dimensional CA
The area of the effective adhesive layer 6 and the auxiliary adhesive layer 8 is defined on the D system. The area of the effective adhesive layer 42 is the overlap area D
And the preliminary area A. Effective areas V2 and V1 of upper sheet 2Y and lower sheet 2X to be laminated
The area bulged outward by a predetermined width from the overlapping area D included in any one of the above is defined as the area where the effective adhesive layer 42 is formed. This width is set in consideration of the transfer error of the effective adhesive layer 42, the thermal shrinkage of the sheet 2, the error in transporting and positioning the sheet 2 to the table 14, and the thermal shrinkage of the sheet 2. In the present embodiment, it is set to 0.5 mm. The area outside the area where the effective adhesive layer 42 is formed is the area where the auxiliary adhesive layer 46 is formed. The amount of the adhesive 4 to be applied depends on the degree of patterning (shading, density, pattern distribution, etc.) in these areas 42 and 46. And the attachment site can be adjusted.

In this embodiment, the area where the effective adhesive layer 42 is formed transfers the adhesive 4 to the entire area, and the area of the auxiliary adhesive layer 46 transfers the adhesive 4 in a thin line shape to form a mesh. Shall be formed.

The formation area of the effective adhesive layer 42 and the auxiliary adhesive layer 46 thus defined is supplied from the three-dimensional CAD system to the laser printer section 18 as information corresponding to the upper layer sheet 2Y, and is supplied to the exposure section. The laser beam is scanned and exposed on the charged photosensitive drum to form an electrostatic latent image on the drum. Further, the electrostatic latent image is converted into an adhesive image by attaching the adhesive 4 instead of the electronic toner. Further, the adhesive image on the drum is transferred to the paper feed tray 16.
Is transferred onto the upper sheet 2 </ b> Y supplied by the above method, and is melted and fixed by heating or the like to form the adhesive layer 40.

Next, as shown in FIG. 2B, the upper sheet 2Y is held by a sheet holding mechanism, and is reversed and adjusted in position via an intermediate tray 28, so that the table 12
To supply. Since the sheet 2Y is transported from the laser printer unit 18 to the table unit 12 in several seconds to several tens of seconds,
Further, since the humidity and temperature environment around the transport unit 22 are adjusted, the sheet 2Y is not distorted due to moisture absorption or the like during the transport.

Then, it is cut on the effective area V1 and the unnecessary area U1 already placed on the table 14, and is superimposed on the lower sheet 2X laminated. In the upper sheet 2Y that has been inverted during the conveyance, the adhesive layers 42 and 46 are in contact with the surface of the lower sheet 2X (see FIG. 2C).

Then, the table 14 is moved upward, and the laminate T (the lower layer sheet 2X and the upper layer sheet 2X) is moved toward the lower surface of the plate 32 disposed above and heated to a predetermined temperature.
Y) is pressed at a predetermined pressure. Thereby, the lower sheet 2
The adhesive 4 interposed between X and the upper sheet 2Y is melted, and the two sheets 2X and 2Y adhere to each other via the adhesive layer 40 (see FIG. 2D). The amount of upward movement (upward position) of the table 14 is controlled by the control unit 9 so that a predetermined pressure set for laminating and bonding is always obtained. At this time, the plate 32 also has an effect of forming the adhesive layer 40 interposed between the sheets 2X and 2Y flat through the sheet 2Y. Accordingly, a layer for bonding the sheets 2X and 2Y and suppressing deformation such as warpage can be formed. Further, the pressurization by the plate 32 is repeatedly performed, and the rebound of the sheet 2 gradually generated after lamination can be suppressed repeatedly, so that the three-dimensional object M without deformation can be formed. Further, the repeated pressing also suppresses the curing shrinkage of the adhesive layer 40. And the adhesive layer 40 itself is the sheet 2
It acts to suppress Y warpage. As a result, even after the lamination, the sheet 2Y is reliably maintained in a state of being laminated flat. Pressing by the plate 32 also has the effect of making the thickness of the sheet 2 itself constant.

The plate 32 is provided with an upper sheet 2Y.
Are pressed at the same time, no displacement of the sheet 2Y occurs. Furthermore, the lower sheet 2X already cut
The unnecessary area U1 is also placed on the table 14, and the entire area of the sheet 2Y is uniformly pressed in order to support the entire upper layer sheet 2Y from below.

Thereafter, the table 14 is moved down, and the adhesive 4 is cooled and solidified, and the first sheet 2X and the second sheet 2
Adhere with Y. In this thermocompression bonding step, the adhesive 4 is melted, and no harmful substances evaporate or odors are generated, and the surrounding environment is not deteriorated.

The vertical movement of the table 14 is controlled by the detection device and the control unit 9, and the table 14 can cut only the upper sheet 2 Y to which the working part of the cutter 35 moved two-dimensionally by the XY plotter 36 is laminated and adhered. Move down to such a position. That is, the pressing position (up position) and the cutting position (down position) are controlled only by the vertical movement of the table 14 in the vertical direction.
By setting only the thickness, it is possible to easily achieve the fine height adjustment of the thickness of each sheet (more precisely, the sum of the thickness of the sheet 2 and the adhesive layer 40) by sequentially stacking the sheets 2, and to reduce the error. Is kept to a minimum.

Then, as shown in FIG. 2E, the cutter 35 operated by the XY plotter 36 on the basis of the data from the data processing unit 8 divides the upper sheet 2Y into an effective area V2 and an unnecessary area U2. Cut into pieces. Since the periphery of the contour of the effective area V2 is adhered by the effective adhesive layer 6 and the auxiliary adhesive layer 8, the upper sheet 2Y does not shift or turn over due to the movement of the cutter 35. Further, as shown in FIG. 3, the upper sheet 2Y is cut into plural pieces at predetermined intervals from the outer periphery of the outline of the effective area V2 to the outer peripheral edge of the upper sheet 2Y. The dividing line 50 is provided for facilitating the removal of the unnecessary area U after the completion of the modeling, and the unnecessary area U can be three-dimensionally divided and eliminated. In particular, if the dividing lines 50 are provided on the concave and convex portions, the removal is easy, and in the case of an object having many irregularities, many dividing lines 50 can be disposed. The dividing line 50 is formed based on data converted from input information from the three-dimensional CAD system by the data processing unit 8 and supplied to the cutting plotter unit 34.

In this manner, all the steps of laminating the upper sheet 2Y are performed, and this step is repeated to laminate the sheets 2 one after another. The cross-sectional shape of the sheet 2 to be stacked next to the sheet 2Y is corrected each time the layers are stacked based on the stacking height of the sheets 2Y detected by the detector. That is, when there is a difference between the detected stack height and the predicted stack height, a three-dimensional object is sliced at a slice position (height) obtained based on the detected stack height to obtain a cross-sectional shape. . Further, the table 14 is displaced downward by the height of the stacked sheet 2Y and the adhesive layer 40, and waits for the supply of the next sheet 2. In this way, the sheet 2 is stacked on the table 14 as shown in FIG. 1, and the three-dimensional object M is formed in the stacked body T on the table 14. After all the sheets 2 have been stacked, the stacked body T is taken out of the table 14, and the stacked portion of the unnecessary area U is removed along the dividing line 50. At a planar location, the unnecessary area U can be removed in a lump, and in a location with particularly severe irregularities, the sheet 2 can be peeled one by one.

The three-dimensional object M in which all unnecessary areas U have been removed has a shape similar to the three-dimensional shape designed by the three-dimensional CAD system. Also, 3
The outer surface of the three-dimensional object M is difficult to peel off because the overlapping area D between the sheets 2 is securely bonded by the adhesive 4 of the effective adhesive layer 42. Further, unlike the case where a photocurable resin is used, the three-dimensional object M can obtain a sufficient adhesive strength without heating for a certain period of time after lamination, and thus can be obtained as a model M immediately after modeling.

In this embodiment, the heater plate portion 30 is used as the bonding means. However, an adhesive which exerts adhesiveness by pressing is used, and a bonding means which only presses is used. can do. In this embodiment, the adhesive 4 is interposed between the sheets 2. However, the adhesive 4 is applied to the upper and lower sheets 2 by a large pressing force.
To form a bonding layer in which the upper and lower sheets 2 impregnated with the adhesive 4 are directly adhered without interposing the adhesive layer 40 between the upper and lower sheets 2. in this case,
Since the adhesive 4 is not interposed, the amount of the adhesive 4 to be used can be reduced.
Can be shaped. In addition, this bonding layer is formed by pressure similarly to the adhesive layer 40, and has the same function.

Further, in this embodiment, plain paper is used as the sheet 2, but the present invention is not limited to this. But,
Plain paper is effective in reducing running costs, and since it is made of pulp, it has the advantage that the adhesive 4 can be easily impregnated and has sufficient heat resistance to hot pressing. The impregnation of the sheet 2 with the adhesive 4 is effective in improving the formability and adhesiveness of the sheet 2.

[0037]

According to the first aspect of the present invention, the mounting table is provided.
The entire sheet can be pressed at once with only vertical movement
In addition, since the adhesive strength etc. can be adjusted,
Errors and thus modeling errors can be reduced. According to the invention described in claim 2, since it is intended to laminate the sheets and vulcanization press, Ru can control the adhesive strength or the like by the vertical movement of the mounting table. According to the third aspect of the present invention, since the adhesive is supplied by electrostatic transfer, no special adhesive interposing means is required, and a simple apparatus configuration capable of diverting a commonly used electrostatic transfer means. It can be.

[Brief description of the drawings]

FIG. 1 is a schematic view of a configuration of a sheet lamination molding apparatus according to an embodiment of the present invention.

FIGS. 2A to 2E are cross-sectional views of a sheet laminating step in an embodiment of the present invention.

FIG. 3 is a diagram showing a cutting state of a sheet by a cutter.

[Explanation of symbols]

 2X: lower layer sheet 2Y: upper layer sheet 4: adhesive 12: mounting table (table section) 18: mounting means (laser printer section) 30: bonding means (heater plate section) 34: cutting means (cutting plotter section) U1: Unnecessary area of upper layer sheet U2: Unnecessary area of lower layer sheet V1: Effective area of upper layer sheet V2: Effective area of lower layer sheet

Claims (3)

(57) [Claims] 1. A device for forming a three-dimensional object sheet which adhesive is applied by laminating, a vertically movable, sheets sequentially the adhesive has been applied
A mounting table to be supplied and stacked, and a pressing surface having a size such that the lower surface side can press the entire surface of the sheet.
And fixed at a predetermined height vertically above the mounting table.
The pressing surface is moved by the upward movement of the mounting table.
Against the seal through the adhesive.
Bonding means for bonding the blades to each other, and the cutting edge fixed at a predetermined height position.
Cutting means for cutting the surface sheet into an effective area and an unnecessary area . 2. An apparatus according to claim 1, wherein said adhesive is an adhesive which exerts an adhesive force when pressed. 3. The apparatus according to claim 1, wherein the intermediary means supplies the adhesive onto the upper sheet by electrostatic transfer.