Printing apparatus and printing method for the same

Abstract

Horizontal joint portions of abutting building boards are constructed in a manner to look straight-line in an external appearance when constructed even in a case that the building board has a dimension error. A printing apparatus for printing a building board of a shiplap joint system composed of a design surface having a horizontal joint portion formed along a longitudinal direction of the building board and an upper and lower shiplap portions formed at an end portion of the building board includes a fixed printing head having a plurality of nozzles for performing printing operation by means of emitting a jet of ink toward the design surface of the building board, in which the printing head performs printing operation along a printing line spaced apart from an edge of the upper shiplap portion or the lower shiplap portion at a constant distance when performing the printing operation for the horizontal joint portion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration schematically showing a printing apparatus according to the present invention;

FIG. 2 is an explanatory view explaining positions of printing heads of the printing apparatus and a building board according to the present invention;

FIG. 3 is a top view showing a condition of three of the building boards having a width of a lower shiplap portion different from each other being conveyed in order, in the printing apparatus according to the present invention;

FIGS. 4A through 4C are illustrations partially showing a cross-sectional view of a construction of each of the building boards shown in FIG. 3 in an advancing direction;

FIG. 5 is an explanatory view explaining a method of printing a horizontal joint portion of the building board having widths of the lower shiplap portion that are different at the front and back in the printing apparatus according to the present invention;

FIG. 6 is an explanatory view explaining a schematic appearance of the building board of a shiplap joint system;

FIG. 7 is an explanatory view explaining a method of jointing the building boards by means of a four-direction shiplap joint system;

FIGS. 8A through 8C are explanatory views explaining a method for fastening the building board with a fastening member, and a deviation of the horizontal joint portions of the abutting building boards.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A printing apparatus according to the present invention will be schematically explained referring to FIG. 1. The printing apparatus of the present invention is provided with a printing head 10, a conveying apparatus (not shown) for moving an object to be printed, i.e., a building board (external wall board) 100, a position detecting device 20 for detecting whether the building board 100 has traveled through a predetermined position at an upstream side relative to the printing head 10, a measuring device 30 for measuring a printing width (width of the design surface in a direction of the shorter side) in a direction orthogonal to a longitudinal direction of the building board 100, an arithmetic unit 40 that creates printing control data while obtaining information from the position detecting device 20 and the measuring device 30, and transmits a printing control signal to the printing head 10. The printing apparatus of the present invention is a line-type printer where the printing head 10 is fixed, and a side of the building board 100 travels as shown in FIG. 1. The building board 100 is configured to travel while both end portions thereof in the longitudinal direction is guided by a guide (not shown) because the building board 100 is required to travel through a constant position in relation to the printing head 10.

As shown in FIG. 1, a moving direction of the building board 100 is defined as x-axis and a direction orthogonal thereto is defined as y-axis.

As shown in FIG. 2, the printing head 10 is composed of four printing heads, 11 of a color Y (yellow), 12 of a color M (magenta), 13 of a color C (cyan), and 14 of a color K (black), and these printing heads are arranged lining at a predetermined intervals along the moving direction of the building board 100. Each of the printing heads includes nozzle arrays, 11A, 12A, 13A, and 14A, arranged in a direction perpendicular to the moving direction of the building board 100.

When the building board 100 moves toward the printing head 10, a printing operation for the Y color is performed first, and then the printing operation for the M color is performed next, and further, the printing operations for the C color and for the K color are performed in order.

As shown in FIG. 2, a reference line p-p is set on the basis of the fixing position of the printing head 10 and the building board 10 is caused to travel while the side end portion of the building board 100 is guided. The guide (not shown) is provided at a position being in parallel with the reference line p-p.

The building board 100 is caused to travel while a side end portion of the lower shiplap portion 110 in a longitudinal direction of the building board 100 is in contact with the guide. This is because problems hardly occur even when the building board 100 is caused to travel at high speed being in contact with the guide in view of the fact that the lower shiplap portion 110 represents a non-design surface that is not seen from outside when the building board 100 is used for construction.

In contrast, the upper shiplap portion 120 in a longitudinal direction serves as a design surface that is seen from outside when the building board 100 is used for construction. Accordingly, for example, the building board 100 is caused to travel while contacting a rubber made roll guider. Thus, the building board 100 is caused to travel while guiding the both side end portions in the longitudinal direction thereof and therefore, the same can be caused to travel through the constant position without meandering.

The printing head 10 of the present invention is that of a line-type, and a dimension of each of the printing heads in a y-axis direction is greater than a printing width H of the building board 100. Accordingly, a surface of the building board 100 is printed by means of once passing the building board 100 under the printing head 10.

The position detecting device 20 may be constructed in a manner so as to include an optical signal transmitter 21 and an optical signal receiver 22 both provided at both sides of a moving path of the building board 100. The position detecting device 20 generates a leading edge detecting signal when detecting the leading edge of the building board 100 moving along a direction of x-axis, and generates a trailing edge detecting signal when detecting the trailing edge of the building board 100, and transmits both of the signals to the arithmetic unit 40.

The measuring device 30 is provided with a first and a second measuring device, 31 and 32, for measuring the printing width H of the building board 100, in a direction orthogonal to the longitudinal direction thereof at a sampling cycle. In concrete terms, both end positions of the printing width H are detected by means of the first and second measuring devices, 31 and 32, and a position of an edge portion of the upper shiplap portion 120 (end portion of a design in the design surface) is detected by means of the first measuring device 31 and a position of an end portion of the design in the design surface that is in contact with the lower shiplap portion 110 is detected by means of the second measuring device 32. Although a structure of the measuring device 30 is not explained in detail at this moment, for example, the dimension may be measured by means of image processing for an image obtained by a CCD imaging device or the like. Alternatively, the dimension may be measured by radiating light of each of the signals and receiving a reflected signal thereof.

A printing method according to the present invention will be explained referring to FIGS. 3 and 4. FIG. 3 shows three building boards, 100A, 100B and 100C, advancing toward the printing head 10 (in a left direction on a paper surface). A line p′-p′ in FIG. 3 shows a guide line for the building board 100 that is in parallel with the reference line p-p described above. FIGS. 4A through 4C show a cross-sectional view of a construction of each of the building boards, 100A, 100B, and 100C, along a direction orthogonal to the moving direction thereof, in FIG. 3. In the building boards, 100A, 100B, and 100C, the width of the lower shiplap portion 110 is formed in approximately the same dimension of one and the same building board, as explained below. Further, it is assumed that there exist variations in the width only from one building board to the other, and that the printing width H is set to keep approximately a constant dimension about one building board throughout the entire length thereof. Furthermore, only one horizontal joint portion 102 (having a width dimension d) is shown as a representative of the horizontal joint portions 102 at the design surface of each of the building boards, 100A, 100B, and 100C, for convenience here.

As shown in FIG. 3, a distance from a lower end portion of the design surface (a borderline between the lower shiplap portion 110 and the design surface) to a lower end portion of the horizontal joint portion 102 is defined as “a”. Further, a dimension control area is set to ±1 mm, and a designing dimension of a width of the lower shiplap portion 110 of the building board 100A is defined as b₀ here, and the width of the lower shiplap portion 110 of the building board 100B is defined as b₁, which is shorter than b₀ by 1 mm, and the width of the lower shiplap portion 110 of the building board 100C is defined as b₂, which is longer than b₀ by 1 mm.

In the present embodiment, any one of the building boards, 100A, 100B, and 100C has approximately the same shape and the same dimension at the surface to be printed (the design surface), and the upper shiplap portion 120 can be equated with the design surface because the same is formed in the surface to be printed. Accordingly, a width of the lower shiplap portion 110 is mainly assumed to have a variation caused by a cutting error. Further, the building board 100 is caused to travel toward the printing head 10 along the guide line p′-p′ while the side end portion of the lower shiplap portion 110 is guided.

In a case that a processing configuration as described above is taken, although the same printed images are formed on the design surfaces of each of the building boards when the printing operation for the design surface is performed on the basis of the border line between the design surface detected by means of detecting the printing width H and the lower shiplap portion 110, the building board is sometimes abutted by a building board having a variation in the width of the lower shiplap portion 110 in a case that the thus printed building board is used for construction. As a result, a problem occurs in which the horizontal joint lines formed at both of the building boards are deviated in vertical directions in the external appearance and continuity in a horizontal direction cannot be secured.

This is because, in the construction of the building boards for the external wall, as shown in FIG. 8B, the arranging position of the building board 100a being disposed at an upper side depends on a fixing position of the fastening member 80 since the fastening member 80 is engaged at an upper end edge of the lower shiplap portion 110c formed at an upper edge portion of the building board 100c arranged at a lower side, and screw fixed. In addition, since the width of the lower shiplap portion 110 has a variation, the horizontal joint line of both the building boards is deviated in the external appearance when the building boards having variety in width in the vertical direction (direction of the shorter side) different from each other are abuttingly arranged.

Accordingly, in the printing method according to the present invention, a process for shifting a printing area in the direction of the shorter side is performed for each of the building boards whose travel position is decided by the guide line p′-p′ shown in FIG. 3.

At this point, a horizontal control line p″-p″ where an edge portion of the upper shiplap portion 120 is positioned on the basis of the building board 100A is set. Further, the area of the printing width H of the building board 100B is shifted up until an upper end edge thereof comes in alignment with the horizontal control line p″-p″ that is located at an upper part of FIG. 3. On the contrary, the area of the printing width H of the building board 100C is shifted down until an upper end edge thereof comes in alignment with the horizontal control line p″-p″. Resulting from the process described above, the portions to be printed as the horizontal joint portion 102 of both of the building boards, 100B and 100C are positioned at the same level, and a selected ink-jet nozzle used for printing the horizontal joint portion 102 of the building board 100A is used without changing a position thereof. A shifting amount is found by means of the arithmetic unit 40 on the based of positional information obtained from the above-described measuring device 30.

On the other hand, although the horizontal joint portion is thus printed, the building board is caused to travel along the guide line p′-p′ while the side end portion of each of the lower shiplap portions 110 is being in contact with the guide. Accordingly, a deviation occurs between an actual printed result of the image for the horizontal joint portion 102 in each of the building boards, 100B and 100C, and the horizontal joint portion 102. Each of the deviations mentioned above is concretely shown in FIGS. 4A through 4C. In other words, an area indicated by a mark d in FIGS. 4A through 4C corresponds to a horizontal joint portion printing area.

In a condition of a construction of the thus printed building board, the horizontal joint portions 102 of the respective building boards, 100B and 100C, are not printed at positions indicated by the reference numerals 102 in FIG. 3, and a horizontal joint line is formed and printed on the basis of the upper shiplap portion 120 formed at a lower end portion of each of the building boards, 100B and 100C, such that a distance from a position of the lower end portion of the upper shiplap portion 120 to the horizontal joint line is equal to that from the position of the lower end portion of the upper shiplap portion 120 to the horizontal joint portion 102 to be a standard position. Therefore, the continuity of the horizontal line in the left and right building boards in the external appearance is secured, and the occurrence of the deviation is avoided resulting in large improvement of the designing characteristic of the external appearance of the external wall.

Next, a printing method, in which a width of the lower shiplap portion 110 is not constant in one building board, will be explained referring to FIG. 5. Although a variation of the width of the lower shiplap portion 110 is exaggeratedly illustrated in FIG. 5, the dimension variation is within an area that can be constructed in practice. As shown in FIG. 5, two of the opposing shorter sides of the building board 100 are approximately in parallel to each other, and two of the opposing longer sides are also in parallel to each other.

First, a boarder line q-q between the design surface and the lower shiplap portion 110 is found by means of the second measuring device 32. Next, a point K of a position, where the width of the lower shiplap portion 110 on the border line q-q is equal to a designed width d₀, is found. Further, a point L of a position that is distant from the point K by a designed distance “a” in which the designed distance “a” is a distance between the point K and the horizontal joint portion 102 is found. Furthermore, a point M of an upper side edge of the horizontal joint portion 102 that is distant form the point L by a designed distance d of the horizontal joint portion 102 is found. Thereafter, lines, r-r and s-s, that respectively pass through the points, L and M, which are in parallel with the border line q-q are found. The printing operation is performed while setting an area that is sandwiched between the parallel lines, r-r and s-s, obtained above to be a horizontal joint printing line. In this case, the printing operation for the horizontal joint printing line is performed upon converting processed printing data in which the printing data for the design surface is rotated in an extent of an angle α formed between the border line q-q and the guide line p′-p′ into printing control data for the nozzle to be used.

Although the embodiment of the present invention is explained above, the description is illustrative of the invention and it will be apparent to those skilled in the art that the invention is not limited to the embodiment disclosed, but is capable of numerous modifications within the scope of the invention as set forth in the claims.

Claims

1. A printing apparatus for printing a building board of a shiplap joint system composed of a design surface having a horizontal joint portion formed along a longitudinal direction of the building board, and an upper and lower shiplap portions formed at an end portion of the building board, comprising: a fixed printing head having a plurality of nozzles for performing printing operation by means of emitting a jet of ink toward the design surface of the building board,wherein the printing head performs printing operation along a printing line spaced apart from an edge of the upper shiplap portion or the lower shiplap portion at a constant distance when performing the printing operation for the horizontal joint portion.

2. The printing apparatus according to claim 1, wherein the printing line is identical of a printing line in a case of printing the horizontal joint portion of the building board having a standard dimension.

3. The printing apparatus according to claim 1, wherein the printing apparatus further comprises a dimension measuring device for measuring a position of an edge of the lower or upper shiplap portion of the building board and a distance from the edge to the horizontal joint portion, and wherein the printing head performs the printing operation along the printing line set on the basis of the distance from the edge to the horizontal joint portion measured by means of the measuring device when performing the printing operation for the horizontal joint portion.

4. A method for printing the building board of a shiplap joint system composed of a design surface having a horizontal joint portion formed along a longitudinal direction of the building board, and an upper and lower shiplap portions formed at an end portion of the building board, comprising the steps of: measuring a position of an edge of a lower shiplap portion of the building board;setting a printing line at a predetermined position from the measured position of the edge of the lower shiplap portion; andprinting the horizontal joint portion of the building board along the printing line.

5. A program capable of being read by means of a computer for performing the method according to claim 4 for printing the building board.