Patent Description:
A liquid discharge apparatus includes a carriage including a recording head that discharges liquid, and a driver that moves the carriage in the main scanning direction. <CIT> discloses a liquid discharge apparatus in which the carriage further includes a jam sensor that detects contact with a recording medium and a lift that moves the recording head to change a distance between the recording head and the recording medium. When the jam sensor detects the contact, the liquid discharge apparatus simultaneously causes the driver to stop moving the carriage and the lift to increase the distance between the recording head and the recording medium.

An object of the present invention is to provide a liquid discharge apparatus that can prevent a liquid discharge unit from being damaged while moving the liquid discharge unit relative to an object.

The dependent claims relate to preferred embodiments of the invention.

According to the present invention, the liquid discharge apparatus can be provided that prevents the liquid discharge unit from being damaged while moving the liquid discharge unit relative to the object.

A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:.

However, the disclosure of this patent specification is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that have the same function, operate in a similar manner, and achieve a similar result.

It is to be noted that the suffixes Y, M, C, K, W, and S attached to each reference numeral indicate only that components indicated thereby are used for forming yellow, magenta, cyan, black, white, and spot color images, respectively, and hereinafter may be omitted when color discrimination is not necessary.

Embodiments of the present invention are described below with reference to the drawings. <FIG> are schematic views illustrating an overall configuration of a liquid discharge apparatus <NUM> according to an embodiment of the present disclosure. <FIG> is a side view, and <FIG> is a plan view of the liquid discharge apparatus <NUM>.

The liquid discharge apparatus <NUM> is installed so as to face an object <NUM> on which images are drawn. The liquid discharge apparatus <NUM> includes an X-axis rail <NUM>, a Y-axis rail <NUM> intersecting the X-axis rail <NUM>, and a Z-axis rail <NUM> intersecting the X-axis rail <NUM> and the Y-axis rail <NUM>. The Y-axis rail <NUM> movably holds the X-axis rail <NUM> along a Y-axis. The X-axis rail <NUM> movably holds the Z-axis rail <NUM> along an X-axis. The Z-axis rail <NUM> movably holds a carriage <NUM> along a Z-axis. Here, the X-axis is an example of a first axis. The Y-axis is an example of a second axis intersecting the first axis. The Z-axis is an example of a third axis intersecting the first axis and the second axis. The carriage <NUM> is an example of a liquid discharge unit, and the carriage <NUM> includes a head <NUM> that discharges ink, which is an example of liquid, toward the object <NUM>. The carriage <NUM> includes a Z-direction driver <NUM> that drives the carriage <NUM> along the Z-axis along the Z-axis rail <NUM>. The Z-axis rail <NUM> includes an X-direction driver <NUM> that drives the Z-axis rail <NUM> along the X-axis along the X-axis rail <NUM>. The X-axis rail <NUM> includes a Y-direction driver <NUM> that drives the X-axis rail <NUM> along the Y-axis along the Y-axis rail <NUM>. The liquid discharge apparatus <NUM> described above discharges ink from the head <NUM> toward the object <NUM> based on drawing data while moving the carriage <NUM> along the X-axis, the Y-axis, and the-Z axis, thereby drawing images on the object <NUM>.

The movement of the carriage <NUM> in the Z-axis direction may not be parallel to the Z-axis, and may be an oblique movement including at least a Z-axis component. Further, the object <NUM> is not limited to a plane. The object <NUM> may have a surface which is nearly vertical or a curved surface with the large radius of curvature, such as a body of a car, a truck, or an aircraft.

Next, the configuration of the carriage <NUM> is described. <FIG> is a perspective view of the carriage <NUM> at a standby position on the Z-axis. The carriage <NUM> is movable along the Z-axis along the Z-axis rail <NUM> by driving force of the Z-direction driver <NUM>. The carriage <NUM> includes a head fixing plate <NUM> for attaching the head <NUM>. In <FIG>, a head 300Y for yellow, a head <NUM> for magenta, a head 300C for cyan, a head <NUM> for black, a head 300W for white, and a head <NUM> for spot color are attached to the head fixing plate <NUM>. Hereinafter, these heads are collectively referred to as heads <NUM>.

Each of the heads <NUM> includes a liquid discharge face (nozzle face) 302a having a plurality of nozzles <NUM>. The nozzle <NUM> is an example of a "liquid discharge port. " Note that the types and number of colors of the inks used in the heads <NUM> are not limited to the above-described example. For example, all inks used in the heads <NUM> may be the same color. The head <NUM> is secured to the head fixing plate <NUM> such that the liquid discharge face (nozzle face) 302a intersects the horizontal plane (i.e., X-Z plane) and the plurality of nozzles <NUM> is obliquely arrayed with respect to the X-axis. Thus, the head <NUM> discharges ink from the nozzle <NUM> in a direction (Z-axis direction in the present embodiment) intersecting the direction of gravity.

As illustrated in <FIG>, a cleaning unit <NUM> is provided to clean the heads <NUM>. The cleaning unit <NUM> moves parallel to the X-axis along a guide rail 9R secured to a frame <NUM>. A motor that moves the cleaning unit <NUM> along the guide rail 9R, a position sensor that detects the position of the cleaning unit <NUM>, for example, at a standby position and a return position, on the X-axis are disposed in the frame <NUM>. With the above configuration, the motor transmits driving force to a belt <NUM> illustrated in <FIG> to move the cleaning unit <NUM> coupled to the belt <NUM> in the positive X-axis direction along the guide rail 9R. Then, the cleaning unit <NUM> cleans the liquid discharge face (nozzle face) 302a and the nozzles <NUM>. When the cleaning unit <NUM> further moves in the positive X-axis direction and reaches the return position, the cleaning unit <NUM> switches the moving direction to the negative X-axis direction and returns to the standby position.

<FIG> is a perspective view of the carriage <NUM> at an ink discharge position on the Z-axis. In <FIG>, the carriage <NUM> has moved in the positive Z-axis direction toward the object <NUM>, unlike the state illustrated in <FIG>. The carriage <NUM> moves along the Z-axis between the ink discharge position illustrated in <FIG> at which ink is discharged toward the object <NUM> and the standby position illustrated in <FIG> at which the head <NUM> is away from the object <NUM> as compared with the ink discharge position. The ink discharge position of the carriage <NUM> is not fixed, but is variable based on drawing data.

<FIG> is a perspective view of the carriage <NUM> to which a contact detection unit <NUM> is attached. The contact detection unit <NUM> includes a first detector <NUM> and a second detector <NUM>. The first detector <NUM> is detachaby attached to the carriage <NUM>, and the second detector <NUM> is detachably attached to the first detector <NUM>. Here, the first detector <NUM> is an example of a first component, and the second detector <NUM> is an example of a second component. Hereinafter, the configuration of the contact detection unit <NUM> is described in detail.

<FIG> are plan views illustrating the heads <NUM> of the carriage <NUM> and the surrounding structure. <FIG> illustrates a state in which the contact detection unit <NUM> is not attached, and <FIG> illustrates a state in which the contact detection unit <NUM> is attached to the carriage <NUM>. The contact detection unit <NUM> includes the first detector <NUM> that is detachaby attached to the carriage <NUM> and the second detector <NUM> that is detachably attached to the first detector <NUM>. The first detector <NUM> includes locks 211a and 211b, and the locks 211a and 211b are detachably attached to attachment portions of the carriage <NUM>. Thus, the contact detection unit <NUM> is detachaby attached to the carriage <NUM>. The first detector <NUM> further includes head protectors <NUM> at the position facing the heads <NUM>. Each head protector <NUM> faces the corresponding nozzle <NUM> of the heads <NUM>. The head protector <NUM> covers each nozzle <NUM> when the contact detection unit <NUM> is attached to the carriage <NUM>, and prevents the nozzles <NUM> from being dried and foreign substances from adhering to the nozzles <NUM>.

<FIG> is a plan view of the contact detection unit <NUM>. In <FIG>, elements identical to those illustrated in <FIG> are given identical reference numerals, and the descriptions thereof are omitted. The first detector <NUM> includes push switches 213a, 213b, 213c, and 213d. Hereinafter, these push switches 213a, 213b, 213c, and 213d are collectively referred to as push switches <NUM>, and each of the push switches 213a, 213b, 213c, and 213d is simply referred to as a push switch <NUM> unless distinguished. The push switch <NUM> operates in response to the movement of the second detector <NUM> attached to the first detector <NUM>. The push switch <NUM> is operated by a pressing force received from the second detector <NUM> when the second detector <NUM> moves in the negative Z-axis direction during a position measurement of the surface of the object <NUM>. A detailed description of the position measurement is deferred. Here, the push switch <NUM> is an example of a position detector.

<FIG> is a rear perspective view of the contact detection unit <NUM>. In <FIG>, elements identical to those illustrated in <FIG> are given identical reference numerals, and the descriptions thereof are omitted. As illustrated in the drawings, each of the head protectors <NUM> provided on the first detector <NUM> faces the position of each nozzle <NUM> of the head <NUM>. The head protectors <NUM> are made of an elastic body such as sponge or rubber. <FIG> illustrates a configuration in which <NUM> head protectors <NUM> corresponding to <NUM> (<NUM> × <NUM>) nozzles <NUM> are provided. When the contact detection unit <NUM> is attached to the carriage <NUM>, the head protector <NUM> covers each nozzle <NUM> of the head <NUM> to prevent the nozzles <NUM> from being dried and foreign substances from adhering to the nozzles <NUM>. The number and arrangement of the nozzles <NUM> are not limited to the above-described example. The nozzles may be arranged in a row in the vertical or horizontal direction instead of the two dimensional arrangement in the vertical and horizontal directions as illustrated. Further, the number of nozzles may be one instead of two or more.

<FIG> are schematic views of the first detector <NUM> and the second detector <NUM> of the contact detection unit <NUM>. <FIG> illustrate the first detector <NUM>. <FIG> is a front view of the first detector <NUM>, and <FIG> is a perspective view of the first detector <NUM> as viewed from the front side. <FIG> illustrate the second detector <NUM>. <FIG> is a rear view of the second detector <NUM>, and <FIG> is a perspective view of the second detector <NUM> as viewed from the rear side.

As illustrated in <FIG>, the first detector <NUM> includes magnets 214a, 214b, 214c, and 214d as an example of a component that generates magnetic force on the front surface. The first detector <NUM> further includes detection plates 215a and 215b on the front surface. Further, the first detector <NUM> includes the locks 211a and 211b that are used when the first detector <NUM> is attached to the carriage <NUM>. Hereinafter, these magnets 214a, 214b, 214c, and 214d are collectively referred to as magnets <NUM>. On the other hand, as illustrated in <FIG>, the second detector <NUM> includes magnets 224a, 224b, 224c, and 224d as an example of a component that generates magnetic force on the back surface. Further, the second detector <NUM> includes conductive flat springs 225a and 225b on the back surface. Hereinafter, these magnets 224a, 224b, 224c, and 224d are collectively referred to as magnets <NUM>.

The first detector <NUM> and the second detector <NUM> are attached to each other such that the front surface of the first detector <NUM> and the back surface of the second detector <NUM> face each other. The second detector <NUM> is attached to the first detector <NUM> by the magnetic force of the magnets <NUM> and the magnets <NUM>. The surface of the magnets <NUM> of the first detector <NUM> slightly projects from the surrounding surface (surface on which the magnets <NUM> are not disposed). On the other hand, the surface of the magnets <NUM> of the second detector <NUM> is slightly recessed from the surrounding surface (surface on which the magnets <NUM> are not disposed). Thus, the magnets <NUM> and the magnets <NUM> form projections and recesses, respectively. Accordingly, when the second detector <NUM> is attached to the first detector <NUM>, the relative position between the first detector <NUM> and the second detector <NUM> is secured at one place, which facilitates positioning. When the second detector <NUM> is attached to the first detector <NUM>, the flat spring 225a of the second detector <NUM> contacts the detection plate 215a of the first detector <NUM>, and the flat spring 225b of the second detector <NUM> contacts the detection plate 215b of the first detector <NUM>.

<FIG> is a perspective view of the first detector <NUM> and the second detector <NUM>. As described above, the first detector <NUM> and the second detector <NUM> are attached to each other by the magnetic force of the magnets <NUM> of the first detector <NUM> and the magnets <NUM> of the second detector <NUM>. As illustrated in <FIG>, the magnetic force is set to an intensity that allows a relative movement between the first detector <NUM> and the second detector <NUM> when an external force is applied to the side surface of the second detector <NUM>, for example, in the direction indicated by arrow F. The above-described relative movement is utilized when the second detector <NUM> detects a collision object such as a protrusion on the surface of the object <NUM> in a verification of position data of the object <NUM>, which is described later. As the second detector <NUM> moves relative to the first detector <NUM>, the flat springs 225a and 225b of the second detector <NUM> separate from the detection plates 215a and 215b of the first detector <NUM>, and the contact detection unit <NUM> outputs an electric signal. Here, the detection plates 215a and 215b are an example of a collision object detector.

<FIG> are schematic views illustrating an electrical connection of the contact detection unit <NUM>. <FIG> is a schematic plan view illustrating the electrical connection of the contact detection unit <NUM>, and <FIG> is a schematic front view illustrating the electrical connection of the contact detection unit <NUM>. The first detector <NUM> is attached to the carriage <NUM> including the head <NUM> with the locks 211a and 211b (see <FIG>). When the first detector <NUM> is attached to the carriage <NUM>, pin-shaped connection terminals 216a and 216b provided on the first detector <NUM> are fitted into jacks provided on the carriage <NUM>, thereby electrically connecting the first detector <NUM> and the carriage <NUM>. The second detector <NUM> is attached to the first detector <NUM> by the magnetic force of the magnets <NUM> and magnets <NUM>. When the second detector <NUM> is attached to the first detector <NUM>, the detection plates 215a and 215b of the first detector <NUM> and the flat springs 225a and 225b of the second detector <NUM> are in contact with each other, and the first detector <NUM> and the second detector <NUM> are electrically connected to each other.

The detection plate 215a of the first detector <NUM> is electrically connected to the connection terminal 216a via the push switch 213a and the push switch 213b. The other detection plate 215b is electrically connected to the connection terminal 216b via the push switch 213c and the push switch 213d. As described above, the push switches <NUM> and the detection plates 215a and 215b provided in the first detector <NUM> and the flat springs 225a and 225b provided in the second detector <NUM> are connected in series to form a series connection circuit. The series connection circuit is electrically conductive when the first detector <NUM> and the second detector <NUM> are attached to the carriage <NUM> at correct positions. For example, the push switch <NUM> is turned on (conductive state) when not pressed and turned off (non-conductive state) when pressed. When the push switch <NUM> is in the conductive state, the contact detection unit <NUM> detects that the first detector <NUM> and the second detector <NUM> are at correct positions, and when the push switch <NUM> is in the non-conductive state, the contact detection unit <NUM> detects that the first detector <NUM> or the second detector <NUM> is not at a correct position.

According to an example not covered by the appended claims, a *non-contact type detector such as an optical sensor may be used instead of the contact type detector such as the push switches <NUM> or the detection plates 215a and 215b. The number and arrangement of the detectors are not limited to the above-described embodiment. An appropriate number and arrangement may be adopted in accordance with the size and the like of the carriage <NUM> and the head <NUM>.

As described above, the liquid discharge apparatus <NUM> according to the present embodiment includes the carriage70 and the contact detection unit <NUM>. The carriage <NUM> has the nozzle <NUM> from which ink is discharged toward the object <NUM>. The carriage <NUM> is movable along at least one of the X-axis and the Y-axis intersecting the X-axis, and movable along the Z-axis intersecting the X-axis and the Y-axis. The Z-axis is parallel to the direction in which the ink is discharged from the nozzle <NUM> toward the object <NUM>. The contact detection unit <NUM> detects contact of the carriage <NUM> with the object <NUM>. The contact detection unit <NUM> is detachably attached to the carriage <NUM>. Accordingly, the carriage <NUM> can be prevented from being damaged while moving relative to the object <NUM>.

Here, when the object <NUM> is a hard metal such as a body of a car, a truck, or an aircraft, an unexpected collision with the object <NUM> may damage the carriage <NUM>. Therefore, it is necessary to prevent the collision. To reliably prevent such a collision, the carriage <NUM> includes a detection mechanism to detect the surface shape of the object <NUM> (e.g., presence or absence of a collision object or the like) on the downstream side in a movement direction of the carriage <NUM>. The detection mechanism may cause the carriage <NUM> to upsize, resulting in the liquid discharge apparatus <NUM> upsizing. In the present embodiment, the contact detection unit <NUM> as the detection mechanism is detachably attached to the carriage <NUM>, thereby preventing the carriage <NUM> from upsizing.

As described above, the contact detection unit <NUM> includes the push switches <NUM> that detect the position of the object <NUM> relative to the carriage <NUM> (i.e., position detection). The contact detection unit <NUM> further includes the detection plates 215a and 215b that detect a collision object on the object <NUM> with which the carriage <NUM> may collide (i.e., collision object detection). Such a simple configuration can implement the position detection and the collision object detection. In addition, the contact detection unit <NUM> includes the first detector <NUM> detachably attached to the carriage <NUM> and the second detector <NUM> detachably attached to the first detector <NUM>, and implements at least one of the position detection and the collision object detection in response to the movement of the first detector <NUM> and the second detector <NUM>. Further, the second detector <NUM> is movable parallel to the movement direction of the carriage <NUM> relative to the first detector <NUM>. Thus, the single contact detection unit <NUM> can implement different types of detection (i.e., the position detection and the collision object detection). That is, the contact detection unit <NUM> detects contact of the carriage <NUM> with the object <NUM> in the position detection and the collision object detection.

As described above, the first detector <NUM> and the second detector <NUM> are attached to each other by the magnets <NUM> and <NUM>. Thus, the second detector <NUM> can be easily positioned relative to the first detector <NUM>.

As described above, the push switch <NUM> operates (i.e., turns on and off to detect the position of the object <NUM>) as the second detector <NUM> moves relative to the first detector <NUM> along the Z-axis, and the detection plates 215a and 215b operate (i.e. separate from the flat springs 225a and 225b to detect a collision object on the object <NUM>) as the second detector <NUM> moves relative to the first detector <NUM> along at least one of the X-axis and the Y-axis. The push switches <NUM> and the flat springs 225a and 225b forms the series connection circuit. When the second detector <NUM> does not move along any of the X-axis, the Y-axis, and the Z-axis, the contact detection unit <NUM> outputs a signal indicating that the series connection circuit is in an electrically conductive state. Thus, the liquid discharge apparatus <NUM> can detect the attachment state of the first detector <NUM> and the second detector <NUM> to the carriage <NUM>.

<FIG> is a block diagram of a portion of the liquid discharge apparatus <NUM> related to movement control of the carriage <NUM>. The liquid discharge apparatus <NUM> includes the carriage <NUM>, the X-direction driver <NUM>, the Y-direction driver <NUM>, the Z-direction driver <NUM>, the contact detection unit <NUM>, a controller <NUM>, a storage unit <NUM>, a display <NUM>, and a control panel <NUM>. The carriage <NUM> is movable relative to the object <NUM> along the X-axis, Y-axis, and Z-axis. The carriage <NUM> includes the head <NUM> (see <FIG>) that discharges ink toward the object <NUM>. The X-direction driver <NUM> drives the carriage <NUM> along the X-axis based on an instruction from the controller <NUM>. The Y-direction driver <NUM> drives the carriage <NUM> along the Y-axis based on an instruction from the controller <NUM>. The Z-direction driver <NUM> drives the carriage <NUM> along the Z-axis based on an instruction from the controller <NUM>.

The contact detection unit <NUM> is detachaby attachable to the carriage <NUM>. Before the carriage <NUM> discharges ink to the object <NUM> (i.e., ink discharge), the position of the object <NUM> may be measured (i.e., position measurement), and position data acquired in the position measurement may be verified (i.e., verification of the position data). The contact detection unit <NUM> is attached to the carriage <NUM> in the position measurement and in the verification of the position data. When the contact detection unit <NUM> is attached to the carriage <NUM>, the above-described series connection circuit is formed, and the signal output from the contact detection unit <NUM> is transmitted to the controller <NUM> via the carriage <NUM>.

The controller <NUM> includes a central processing unit (CPU) and a read-only memory (ROM). The CPU controls the entire liquid discharge apparatus <NUM>. The ROM stores programs, which include a program to cause the CPU to perform the control of a drawing operation, for example, and other fixed data. The controller <NUM> further includes a random access memory (RAM) and an interface (I/F). The RAM temporarily stores drawing data and the like. The I/F is used when the controller <NUM> receives drawing data and the like from a host such as a personal computer (PC) to transmits data and signals. The controller <NUM> is an example of a control unit.

The controller <NUM> stores and reads the detection result of the contact detection unit <NUM> in and from the storage unit <NUM>. The controller <NUM> causes the X-direction driver <NUM>, the Y-direction driver <NUM>, and the Z-direction driver <NUM> to move the carriage <NUM> along the X-axis, the Y-axis, and the Z-axis. The controller <NUM> controls the ink discharge from the head <NUM> mounted on the carriage <NUM>. Further, when an abnormality occurs in the operations of the carriage <NUM> and the head <NUM>, the controller <NUM> displays information indicating the abnormality to a user on the display <NUM>. The controller <NUM> receives an instruction from the control panel <NUM> and executes a process corresponding to the instruction.

The storage unit <NUM> stores the position data (three dimensional coordinate data) in the position measurement, data in the verification of the position data, and the like from the contact detection unit <NUM>. When an abnormality occurs in the liquid discharge apparatus <NUM>, the display <NUM> displays the information indicating the abnormality to the user. The control panel <NUM> is used to input a value (coordinates) for specifying a drawing area 100a (see <FIG>) where ink is discharged onto the object <NUM>, a moving speed of the carriage <NUM>, a distance between the head <NUM> and the object <NUM>, and the like. Further, the three dimensional coordinate data indicating the surface shape of the object <NUM> can be designated on the control panel <NUM>. Note that the display <NUM> and the control panel <NUM> may be combined into one screen with a touch panel or the like.

Next, the position measurement by the contact detection unit <NUM> is described. <FIG> is a schematic diagram illustrating a relation between the object <NUM> and the drawing area 100a. The object <NUM> has various sizes and shapes, and the positional relation between the liquid discharge apparatus <NUM> and the object <NUM> changes depending on the installation state. Therefore, prior to the ink discharge to the object <NUM>, the liquid discharge apparatus <NUM> acquires the position data of the surface of the object <NUM>.

For example, in the case of a rectangular drawing area 100a as illustrated in <FIG>, coordinate data of a drawing start position P1 and a drawing end position P2 is stored in the storage unit <NUM> of the liquid discharge apparatus <NUM>. Thus, the drawing area 100a is determined. In the example illustrated in <FIG>, the coordinate data indicates X and Y coordinates, but is not limited thereto. Depending on the installation state of the liquid discharge apparatus <NUM> and the object <NUM>, the liquid discharge apparatus <NUM> may be inclined with respect to the object <NUM>, or a collision object such as a protrusion may be present on the surface of the object <NUM>. Therefore, the coordinate data preferably includes three dimensional coordinates including the Z-direction component.

The drawing area 100a is a range in which the carriage <NUM> of the liquid discharge apparatus <NUM> moves. Although the drawing area 100a is the range in which the carriage <NUM> moves, an image is not necessarily drawn on the entire surface of the drawing area 100a. Multiple drawing areas, in which the carriage <NUM> can move, may be present in the same object <NUM>. When a collision object such as a protrusion is present in the drawing area 100a, position data of the collision object is stored in the storage unit <NUM>. As an example of the collision object, when the object <NUM> is a body of a truck, a reinforcing rib of the body corresponds to the collision object.

Next, the operation of the position measurement of the drawing area 100a of the object <NUM> by the contact detection unit <NUM> is described. <FIG> are schematic views for explaining the position measurement. <FIG> is a plan view illustrating a state in which the contact detection unit <NUM> is separated from the object <NUM>, and <FIG> is a plan view illustrating a state in which the contact detection unit <NUM> contacts the object <NUM>. Prior to the ink discharge to the object <NUM>, the liquid discharge apparatus <NUM> performs the position measurement to acquire position data of the drawing area 100a of the object <NUM> and grasp the surface shape of the drawing area 100a.

In the position measurement, first, the carriage <NUM> at the standby position on the Z-axis is moved toward the object <NUM> in the positive Z-axis direction. As a detection face 220a of the second detector <NUM> contacts the object <NUM>, the second detector <NUM> moves in the negative Z-axis direction relative to the carriage <NUM>. As the second detector <NUM> moves in the negative Z-axis direction, the second detector <NUM> presses the first detector <NUM> in the negative Z-axis direction. Then, as the first detector <NUM> moves in the negative Z-axis direction relative to the carriage <NUM>, the first detector <NUM> presses the push switch <NUM> toward the carriage <NUM>. Accordingly, the push switch <NUM> is operated, and the contact detection unit <NUM> detects the position of the surface of the object <NUM>. At this time, the position data of the carriage <NUM> is stored in the storage unit <NUM> of the liquid discharge apparatus <NUM>. The above-described operation is performed multiple times from the drawing start position P1 to the drawing end position P2 in the drawing area 100a to acquire data indicating the surface shape of the drawing area 100a.

<FIG> is a schematic diagram illustrating an example of an electrical connection of the contact detection unit <NUM>. The push switches <NUM> and the detection plates 215a and 215b provided in the first detector <NUM> and the flat springs 225a and 225b provided in the second detector <NUM> form the series connection circuit. <FIG> illustrates a state in which the push switch 213d among the four push switches <NUM> detects the position of the object <NUM>. The position and the number of the push switches <NUM> to be operated change depending on the surface shape of the object <NUM>. In the above configuration, the push switch <NUM> is turned off by the pressing force when the surface position of the object <NUM> has been detected. When the push switch <NUM> is turned off, the series connection circuit is in the non-conductive state. At this time, the coordinate data, which indicates the surface position of the object <NUM> at the current position, is stored in the storage unit <NUM>.

<FIG> is a schematic diagram illustrating a case in which coordinate data of the object <NUM> is automatically acquired. After setting the drawing start position P1 and the drawing end position P2 from the control panel <NUM>, a user sets X grid lines 100b and Y grid lines 100c with certain setting values. The setting values include designation of the number of grid lines or the interval between grid lines. After the X grid lines 100b and the Y grid lines 100c are set, the liquid discharge apparatus <NUM> performs the position measurement of the surface of the object <NUM> at the intersections of the X grid lines 100b and the Y grid lines 100c, and automatically acquires coordinate data (three dimensional coordinate data of X, Y, and Z).

The user can obtain the coordinate data at fine intervals or at coarse intervals according to the setting value of the grid lines set by the user. The user may set only the drawing start position P1 and the grid lines, and the drawing end position P2 may be determined in accordance with the grid lines. Further, when a collision object such as a protrusion that affects drawing is present at a certain portion in the drawing area 100a of the object <NUM>, the liquid discharge apparatus <NUM> may perform the position measurement of the certain portion having the X and Y coordinates specified by the user, and add position data in the position measurement to the coordinate data.

<FIG> are schematic views illustrating a positional relation between the carriage <NUM> and the surface shape of the object <NUM> in the position measurement. <FIG> illustrates a case in which the surface of the object <NUM> is inclined, and <FIG> illustrate a case in which a protrusion is present on the surface of the object <NUM>.

As illustrated in <FIG>, when the object <NUM> is inclined with respect to the liquid discharge apparatus <NUM>, coordinates between two points of coordinates (Xm, Ym, Zm) and coordinates (Xn, Yn, Zn) are acquired by proportional calculation. Thus, during the ink discharge, the carriage <NUM> moves along the inclination of the object <NUM> so that the distance between the object <NUM> and the head <NUM> is constant. In the case in which the coordinates between two points are acquired by the proportional calculation described above, the liquid discharge apparatus <NUM> may erroneously recognize a protrusion or a step between the two points of the coordinates (Xm, Ym, Zm) and the coordinates (Xn, Yn, Zn) as illustrated in <FIG> as an inclined surface. As illustrated in <FIG>, when a protrusion is present between the coordinates of two points, the liquid discharge apparatus <NUM> may overlooks the protrusion. Further, as illustrated in <FIG>, even when the liquid discharge apparatus <NUM> recognizes the presence of a protrusion in the position measurement, the carriage <NUM> may fail to avoid the protrusion and may collide with the protrusion.

The reason why such situations occur is that the movement of the carriage <NUM> is different between the position measurement and the ink discharge. In the position measurement, the carriage <NUM> is moved along the X-axis and Y-axis. After reaching the measurement point, the carriage <NUM> is moved along the Z-axis. On the other hand, in the ink discharge to the object <NUM>, the carriage <NUM> is continuously moved along in the X-axis, the Y-axis, and the Z-axis while keeping the distance between the object <NUM> and the carriage <NUM> constant.

Therefore, in the present disclosure, the liquid discharge apparatus <NUM> executes a process in which position data in the position measurement is verified after the position measurement and before the ink discharge (i.e., the verification of the position data). In this verification, the carriage <NUM> is moved relative to the object <NUM> in accordance with the coordinate data indicating the movement trajectory of the carriage <NUM> obtained based on the position data in the position measurement to check the presence or absence of a protrusion or the like overlooked in the position measurement. The movement of the carriage <NUM> in the verification is the same as the movement in the ink discharge except that ink is not discharged. Therefore, if a new protrusion or the like is not present in the verification, failure of drawing does not occur in the actual ink discharge. The verification is described in further detail later.

<FIG> are schematic perspective views illustrating a relation between the detection face 220a of the contact detection unit <NUM> and the liquid discharge face (nozzle face) 302a. <FIG> illustrates the detection face 220a of the contact detection unit <NUM>, and <FIG> illustrates the liquid discharge face (nozzle face) 302a of the nozzles <NUM> in the carriage <NUM>. In <FIG>, the contact detection unit <NUM> attached to the carriage <NUM> includes the first detector <NUM> and the second detector <NUM>. The position of the carriage <NUM> relative to the object <NUM> is measured by the contact of the detection face 220a of the second detector <NUM> with the object <NUM>. On the other hand, the carriage <NUM> has the nozzle <NUM>, which is an example of a liquid discharge port, at a portion to which the contact detection unit <NUM> is attached. In the present embodiment, the heads <NUM> having a plurality of nozzles <NUM> is mounted on the carriage <NUM>. The plurality of nozzles <NUM> forms the liquid discharge face (nozzle face) 302a.

In <FIG>, the heads <NUM> includes six heads arranged along the Y-axis, and each head has eight nozzles <NUM> along the X-axis. That is, the head <NUM> has <NUM> nozzles <NUM>. In the present embodiment, the surface formed by the <NUM> nozzles <NUM> is defined as the liquid discharge face (nozzle face) 302a. Alternatively, the surface having a shape corresponding to the exterior of the head <NUM> may be defined as the liquid discharge face (nozzle face) 302a. The number and arrangement of the nozzles <NUM> are not limited to the above-described embodiment. The nozzles <NUM> may be arranged in a row in the vertical or horizontal direction instead of the two dimensional arrangement in the vertical and horizontal directions as illustrated. Further, the number of nozzles <NUM> may be one instead of two or more.

The above description is based on the example in which the detection face 220a of the second detector <NUM> is larger in area than the liquid discharge face 302a of the carriage <NUM>. However, the height (along the Y-axis), the width (along the X-axis), and the thickness (along the Z-axis) of the detection face 220a may be appropriately changed in accordance with the surface shape or the surface state of the object <NUM> to be measured. Here, the area of the detection face 220a refers to the area of a projection surface of the detection face 220a projected onto the liquid discharge face 302a from the object <NUM> side along the Z-axis. For example, when the detection face 220a is larger in area than the liquid discharge face 302a as illustrated in <FIG>, the liquid discharge face 302a falls within the projection surface of the detection face 220a from the object <NUM> side.

<FIG> are schematic views of the contact detection unit <NUM> having the detection face 220a of different area. <FIG> illustrates a case in which the detection face 220a of the second detector <NUM> is larger in area than the liquid discharge face 302a. <FIG> illustrates a case in which the detection face 220a of the second detector <NUM> is equivalent in area to the liquid discharge face 302a. <FIG> illustrates a case in which the detection face 220a of the second detector <NUM> is smaller in area than the liquid discharge face 302a.

As illustrated in <FIG>, in the case in which the detection face 220a of the second detector <NUM> is larger in area than the liquid discharge face 302a, a wide range of the object <NUM> can be detected at a time in the position measurement of the object <NUM>. Therefore, the position detection can be performed in a short time when the object <NUM> has a substantially flat surface. As illustrated in <FIG>, in the case in which the detection face 220a of the second detector <NUM> is equivalent in area to the liquid discharge face 302a, the position detection can be performed at an interval corresponding to the width of the head <NUM>. As illustrated in <FIG>, in the case in which the detection face 220a of the second detector <NUM> is smaller in area than the liquid discharge face 302a, the position detection of the object <NUM> can be finely performed. Therefore, even when the object <NUM> has a collision object such as a protrusion or the like at a narrow interval, the collision object can be prevented from being overlooked.

As described above with reference to <FIG>, in the contact detection unit <NUM>, the detection face 220a that contacts the object <NUM> to detect the position of the object <NUM> relative to the carriage <NUM> has a larger area than the liquid discharge face 302a of the nozzles <NUM>. As a result, a wide range can be detected at a time, and the position detection can be completed in a short time for the flat object <NUM>.

As described above with reference to <FIG>, in the contact detection unit <NUM>, the detection face 220a that contacts the object <NUM> to detect the position of the object <NUM> relative to the carriage <NUM> has an area equivalent to the area of the liquid discharge face 302a of the nozzles <NUM>. As a result, the position can be accurately detected at an interval corresponding to the width of the head <NUM> used for actual ink discharge.

As described above with reference to <FIG>, in the contact detection unit <NUM>, the detection face 220a that contacts the object <NUM> to detect the position of the object <NUM> relative to the carriage <NUM> has a smaller area than the liquid discharge face 302a of the nozzles <NUM>. As a result, the position of the object <NUM> can be finely detected, thereby preventing a collision object on the object <NUM> from being overlooked.

Next, the verification of the position data is described. The liquid discharge apparatus <NUM> according to the present disclosure executes the process of verifying the position data in the position measurement after the position measurement and before the ink discharge. In this verification, the carriage <NUM> is moved relative to the object <NUM> in accordance with the coordinate data indicating the movement trajectory of the carriage <NUM> obtained based on the position data in the position measurement to check the presence or absence of a protrusion or the like overlooked in the position measurement. The movement of the carriage <NUM> in the verification is the same as the movement in the ink discharge except that ink is not discharged.

<FIG> is a flowchart illustrating the verification of the position data. First, the carriage <NUM> to which the contact detection unit <NUM> is attached moves to the drawing start position P1 set by the user on the control panel <NUM> (step S1). Next, the carriage <NUM> starts moving from the drawing start position P1 under control of the controller <NUM> of the liquid discharge apparatus <NUM> (step S2).

The controller <NUM> determines three dimensional (X, Y, and Z) coordinates indicating the movement trajectory of the carriage <NUM> based on the position data detected by the position detector (the push switches <NUM>) in the position measurement. Then, the controller <NUM> moves the carriage <NUM> toward the drawing end position P2 set by the user on the control panel <NUM> in accordance with the three dimensional coordinate data. While the carriage <NUM> moves, the contact detection unit <NUM> attached to the carriage <NUM> detects a protrusion of the object <NUM> (step S3). When the contact detection unit <NUM> does not detect a protrusion while the carriage <NUM> moves from the drawing start position P1 to the drawing end position P2, the carriage <NUM> stops moving (step S4). Detailed description of a section A of the flowchart is deferred.

As the movement of the carriage <NUM> is completed, the controller <NUM> of the liquid discharge apparatus <NUM> displays that the verification is completed on the display <NUM> to indicate the completion of the verification to a user (step S5). Then, the carriage <NUM> moves to the drawing start position P1 (step S6). The carriage <NUM> that has moved to the drawing start position P1 stands by in preparation for the ink discharge to the object <NUM>.

On the other hand, when the contact detection unit <NUM> detects a protrusion while the carriage <NUM> moves from the drawing start position P1 to the drawing end position P2, the controller <NUM> of the liquid discharge apparatus <NUM> records position data indicating the position of the protrusion (step S7). For example, in the present embodiment, the position data is stored in the storage unit <NUM> of the liquid discharge apparatus <NUM> to record the position of the protrusion.

Next, the controller <NUM> of the liquid discharge apparatus <NUM> causes the Z-direction driver <NUM> to move the carriage <NUM> in the negative Z-axis direction, and the carriage <NUM> moves to the standby position on the Z-axis (step S8). Thus, the carriage <NUM> is retracted away from the protrusion. The controller <NUM> of the liquid discharge apparatus <NUM> stops the X-direction driver <NUM> and the Y-direction driver <NUM> to stop the carriage <NUM> (step S9).

Next, the controller <NUM> of the liquid discharge apparatus <NUM> displays the position data of the protrusion on the display <NUM> to notify the user (step S10). Then, a display screen of the control panel <NUM> transitions to the position measurement screen (step S11). On the position measurement screen, the user adds the position data of the protrusion to the original position data in the position measurement as appropriate. The position data of the protrusion may be manually added by the user after the user confirms the state of the object <NUM> and determines whether to add the position data. Alternatively, the position data may be automatically added by the liquid discharge apparatus <NUM>.

As described above, when the contact detection unit <NUM> detects a protrusion in step S3, the position data of the protrusion is added to the original position data in the position measurement, and the process is executed again from step S1. When the contact detection unit <NUM> does not detect the protrusion while the carriage <NUM> moves from the drawing start position P1 to the drawing end position P2, the verification is completed, and the process proceeds to steps of actually discharging ink toward the object <NUM>. After the verification is completed, the process does not necessarily proceed to the ink discharge. After the first verification, the position measurement may be performed again. By repeating the position measurement of the object <NUM> and the verification of the position data, three dimensional coordinate data of the object <NUM> can be acquired more accurately, and the ink discharge suitable for the shape of the object <NUM> can be performed.

The three dimensional coordinate data once created by the position measurement and the verification is stored in the storage unit <NUM> of the liquid discharge apparatus <NUM>. Accordingly, the three dimensional coordinate data is available when the ink discharge is performed on the object <NUM> having the same shape. In addition, even when the relative position between the liquid discharge apparatus <NUM> and the object <NUM> is changed, the coordinate data regarding the shape of the object <NUM> can be used. Therefore, when the object <NUM> has the same shape, the user can omit at least a part of the verification by using the position data in the position measurement.

In the detection of the protrusion of the object <NUM>, the second detector <NUM> detects a protrusion as the protrusion of the object <NUM> collides with the second detector <NUM> of the contact detection unit <NUM> (detailed description is deferred). According to an example not covered by the appended claims, the protrusion may be detected not by physical contact as described above but also by optical detection using laser light or by image processing. According to this example, an object to be detected is not limited to the protrusion of the object <NUM>. When the detection is performed by optical or image processing as described above, arbitrary portion on the object <NUM> can be detected. For example, a hole provided in the object <NUM>, or a place where drawing is intentionally avoided (e.g., an image already drawn or a masking portion) can be detected as a detection target.

<FIG> is a schematic diagram illustrating a positional relation between the carriage <NUM> at the time of the verification and at the time of the ink discharge. In <FIG>, the carriage <NUM> depicted by the solid line indicates the position relative to the object <NUM> in the verification of the position data. In the ink discharge to the object <NUM>, the carriage <NUM> is shifted by a distance L1 in the positive Z-axis direction as depicted by the broken line. In the verification, the contact detection unit <NUM> is attached to the carriage <NUM>. Therefore, the distance L1 is set in consideration of the thickness of the contact detection unit <NUM> along the Z-axis. In the ink discharge to the object <NUM>, the controller <NUM> moves the carriage <NUM> to the position corrected by the distance L1 and cause the carriage <NUM> to discharge ink.

In addition, the movement trajectory and the moving speed of the carriage <NUM> in the verification of the position data are set to the same as the setting in the ink discharge to the object <NUM>. When a liquid discharge apparatus discharges ink to an object such as a body of a car, a truck, or an aircraft, the liquid discharge apparatus is a large system. Accordingly, the rails and the apparatus frame may be bent due to the weights of the carriage <NUM>, the X-axis rail <NUM>, Y-axis rail <NUM>, and Z-axis rail <NUM> and the inertia force caused by the movement of the carriage <NUM>. Therefore, the verification of the position data is preferably performed in accordance with the movement of the carriage <NUM> when the ink is actually discharged to the object <NUM>. If the setting of the movement trajectory and the moving speed of the carriage <NUM> in the verification of the position data is the same as the setting in the ink discharge to the object <NUM>, the position data along the movement trajectory of the carriage <NUM> can be accurately verified.

<FIG> are schematic views illustrating an example in which a protrusion is detected in the verification. <FIG> illustrates a state before the protrusion is detected, and <FIG> illustrates a state in which the protrusion is detected. A description is given below of the verification when a protrusion <NUM> overlooked in the position measurement is present on the surface of the object <NUM>. In the state illustrated in <FIG>, the second detector <NUM> is attached to the first detector <NUM> at the correct position. Therefore, the detection plates 215a and 215b of the first detector <NUM> and the flat springs 225a and 225b of the second detector <NUM> contact each other, and the series connection circuit is in the electrically conductive state.

As the carriage <NUM> moves in the positive X-axis direction and reaches the protrusion <NUM>, the second detector <NUM> collides with the protrusion <NUM> and does not further move in the positive X-axis direction. Since the second detector <NUM> is movable parallel to the movement direction of the carriage <NUM> relative to the first detector <NUM>, the second detector <NUM> slides in the direction opposite to the movement direction of the carriage <NUM> due to the collision with the protrusion <NUM>. Accordingly, the detection plates 215a and 215b of the first detector <NUM> are separated from the flat springs 225a and 225b of the second detector <NUM>, and the series connection circuit is in the non-conductive state. After the protrusion <NUM> is detected, the process is executed based on steps illustrated in <FIG>.

<FIG> are schematic diagrams illustrating an example of an electrical connection of the series connection circuit. <FIG> illustrates a state in which the contact detection unit <NUM> is correctly attached to the carriage <NUM>, and <FIG> illustrates a state in which the second detector <NUM> of the contact detection unit <NUM> is not correctly attached. <FIG> illustrates a state in which the protrusion <NUM> illustrated in <FIG> is detected.

<FIG> is a schematic diagram illustrating an example of the movement trajectory of the carriage <NUM>. The carriage <NUM> moves from the drawing start position P1 in the positive X-axis direction and reaches the return position. Then, the carriage <NUM> moves by a movement amount La in the positive Y-axis direction (i.e., line feed). After the line feed, the carriage <NUM> moves in the negative X-axis direction and reaches the other return position. Then, the carriage <NUM> again moves by the movement amount La in the positive Y-axis direction (i.e., line feed). While this movement is repeated, the carriage <NUM> moves to the drawing end position P2 along the movement trajectory indicated by the arrow.

If the movement amount La of the carriage <NUM> for the line feed is constant, the carriage <NUM> may overrun out of the drawing area 100a in the last line. If the carriage <NUM> moves out of the drawing area 100a, when the contact detection unit <NUM> detects a protrusion, the liquid discharge apparatus <NUM> does not distinguish whether the protrusion is detected inside the drawing area 100a or outside the drawing area 100a.

Accordingly, the carriage <NUM> preferably moves from the drawing start position P1 to the drawing end position P2 without moving out of the drawing area 100a. Therefore, in the present embodiment, a movement amount Lb of the carriage <NUM> in the last line is smaller than the movement amount La, and the movement trajectory of the carriage <NUM> is controlled so that the position of the carriage <NUM> in the last line coincides with the drawing end position P2.

Preferably, the movement setting such as the movement amounts La and Lb is the same in the verification of the position data and the ink discharge to the drawing object <NUM>. Instead of changing only the movement amount Lb of the last line as described above, the movement amount La and the movement amount Lb may be equalized so that the carriage <NUM> finally falls within the drawing area 100a.

<FIG> is a flowchart illustrating the section A of the verification flow illustrated in <FIG> in detail. In order to prevent the carriage <NUM> from moving out of the drawing area 100a, the liquid discharge apparatus <NUM> determines the number of times and amount of movement of the carriage <NUM> while checking the remaining amount of the drawing area 100a along the Y-axis.

The controller <NUM> drives the X-direction driver <NUM> to move the carriage <NUM> from the drawing start position P1 in the positive X-axis direction as illustrated in <FIG> (step S21). As the carriage <NUM> moves in the positive X-axis direction, a counter that counts the number of moves of the carriage <NUM> along the X-axis adds <NUM> to a count value (step S22). When the carriage <NUM> reaches the end point (return position) on the positive side along the X-axis, the controller <NUM> determines whether the drawing area 100a remains along the Y-axis (step S23).

When the drawing area 100a does not remain, which means that the carriage <NUM> has reached the drawing end position P2, the counter resets the number of moves of the carriage70 along the X-axis (step S33). Then, the carriage <NUM> stops moving. On the other hand, when the drawing area 100a remains in step S23, the controller <NUM> determines whether the remaining amount is equal to or greater than the movement amount La (step S24). Here, the movement amount La corresponds to the height (length) of the carriage <NUM> (liquid discharge face 302a) along the Y-axis. Therefore, the terms "the remaining amount of the drawing area 100a along the Y-axis is equal to or greater than the movement amount La" means that a line feed in the positive Y-axis direction can be performed by the height of the carriage <NUM>.

When the remaining amount is equal to or greater than the movement amount La in step S24, the controller <NUM> drives the Y-direction driver <NUM> to move the carriage <NUM> by the movement amount La in the positive Y-axis direction (step S25). When the remaining amount is less than the movement amount La in step S24, the controller <NUM> drives the Y-direction driver <NUM> to move the carriage <NUM> by the movement amount Lb in the positive Y-axis direction (step S26). As described with reference to <FIG>, the movement amount Lb is smaller than the movement amount La, and is set so that the carriage <NUM> coincides with the drawing end position P2.

After the carriage <NUM> moves in the positive Y-axis direction in step S25 or step S26, the controller <NUM> drives the X-direction driver <NUM> to move the carriage <NUM> in the negative X-axis direction (step S27). As the carriage <NUM> moves in the negative X-axis direction, the counter that counts the number of moves of the carriage <NUM> along the X-axis adds <NUM> to the count value (step S28). When the carriage <NUM> reaches the end point (return position) on the negative side along the X-axis, the controller <NUM> determines whether the drawing area 100a remains along the Y-axis (step S29).

When the drawing area 100a does not remain, which means that the carriage <NUM> has reached the drawing end position P2, the counter resets the number of moves of the carriage70 along the X-axis (step S33). Then, the carriage <NUM> stops moving. On the other hand, when the drawing area 100a remains in step S29, the controller <NUM> determines whether the remaining amount is equal to or greater than the movement amount La (step S30). When the remaining amount is equal to or greater than the movement amount La in step S30, the controller <NUM> drives the Y-direction driver <NUM> to move the carriage <NUM> by the movement amount La in the positive Y-axis direction (step S31). When the remaining amount is less than the movement amount La in step S30, the controller <NUM> drives the Y-direction driver <NUM> to move the carriage <NUM> by the movement amount Lb in the positive Y-axis direction (step S32).

After the carriage <NUM> moves in the positive Y-axis direction in step S31 or step S32, the process returns to the step S21, and the controller <NUM> repeats the above-described flow until the remaining amount of the drawing area 100a runs out. As described above, the controller <NUM> controls the carriage <NUM> within the drawing area 100a so that the carriage <NUM> does not move out of the drawing area 100a. Therefore, the liquid discharge apparatus <NUM> can accurately perform the position measurement, the verification, and the ink discharge in a determined drawing area 100a.

<FIG> is a schematic view illustrating an example of the display screen of the control panel <NUM> of the liquid discharge apparatus <NUM>. A user can input X and Y coordinate data to determine the drawing start position P1 and the drawing end position P2 of the drawing area (print range) 100a, and select the moving speed of the carriage <NUM> on the control panel <NUM>. In addition, the user can designate the three dimensional coordinate data (body data) indicating the surface shape of the object <NUM> and input the distance (set gap) between the head <NUM> and the object <NUM> on the control panel <NUM>.

<FIG> is a schematic view of a fall prevention component that prevents the second detector <NUM> from falling off the contact detection unit <NUM>. The contact detection unit <NUM> includes the first detector <NUM> and the second detector <NUM> that are attached to each other by the magnetic force of the magnets <NUM> and <NUM> as described above. Accordingly, if the second detector <NUM> moves relative to the first detector <NUM> by a distance equal to or greater than the size of the magnets <NUM> and <NUM> due to the detection of the protrusion, the second detector <NUM> may fall from the first detector <NUM> and may be damaged.

To prevent the second detector <NUM> from falling, the first detector <NUM> and the second detector <NUM> may be coupled to each other by a string-shaped component <NUM>. The string-shaped component <NUM> includes a string, a wire, a chain, and the like. Note that the string, the wire, and the chain are an example of the fall prevention component. As described above, in the present embodiment, the string-shaped component <NUM> that prevents the second detector <NUM> from falling from the first detector <NUM> is provided between the first detector <NUM> and the second detector <NUM>. Accordingly, even when the second detector <NUM> is detached from the first detector <NUM>, the string-shaped component <NUM> can prevent the second detector <NUM> from falling off and from being damaged or lost.

<FIG> is a schematic view of a liquid discharge apparatus <NUM> according to a variation of the present invention. <FIG> is an enlarged perspective view of the liquid discharge apparatus <NUM> according to the variation. The liquid discharge apparatus <NUM> includes a linear rail <NUM> and a multi-articulated robot <NUM>. The linear rail <NUM> guides a carriage <NUM> as a liquid discharge unit that reciprocally and linearly moves along the linear rail <NUM>. The multi-articulated robot <NUM> appropriately moves the linear rail <NUM> to a predetermined position and holds the linear rail <NUM> at the predetermined position. The multi-articulated robot <NUM> includes a robot arm 405a that is freely movable like a human arm by a plurality of joints. The multi-articulated robot <NUM> can freely move a distal end of the robot arm 405a and arrange the distal end of the robot arm 405a at an accurate position.

An industrial robot of a six-axis control-type having six axes (six joints) can be used as the multi-articulated robot <NUM>, for example. According to the multi-articulated robot <NUM> of the six-axis control-type, it is possible to previously teach data related to a movement of the multi-articulated robot <NUM>. As a result, the multi-articulated robot <NUM> can accurately and quickly position the linear rail <NUM> at a predetermined position facing an object <NUM> (an aircraft in the present embodiment). The number of axes of the multi-articulated robot <NUM> is not limited to six, and a multi-articulated robot having an appropriate number of axes such as five axes or seven axes can be used.

The robot arm 405a of the multi-articulated robot <NUM> includes a fork-shaped support <NUM> bifurcated into two. A vertical linear rail 423a is attached to a tip of a left branch 424a of the support <NUM>, and a vertical linear rail 423b is attached to a tip of a right branch 424b of the support <NUM>. The vertical linear rail 423a and the vertical linear rail 423b are parallel to each other. Further, both ends of the linear rail <NUM> that movably holds the carriage <NUM> are supported by the vertical linear rails 423a and 423b. The carriage <NUM> includes, for example, the head <NUM> described with reference to <FIG> and the like, a plurality of heads <NUM> that discharges inks of respective colors (e.g., yellow, magenta, cyan, black, and white), or a head <NUM> having a plurality of nozzle rows. The inks of respective colors are respectively supplied from ink tanks <NUM> to the heads <NUM> or the nozzle rows of the head <NUM> of the carriage <NUM>.

In the liquid discharge apparatus <NUM>, the multi-articulated robot <NUM> moves the linear rail <NUM> to a desired drawing area of the object <NUM>, and the heads <NUM> are driven to draw images on the object <NUM> while moving the carriage <NUM> along the linear rail <NUM> according to drawing data. When the liquid discharge apparatus <NUM> ends drawing of one line, the liquid discharge apparatus <NUM> causes the vertical linear rails 423a and 423b of the multi-articulated robot <NUM> to move the heads <NUM> of the carriage <NUM> from the one line to the next line. The liquid discharge apparatus <NUM> repeats the above-described operation to draw images on the desired drawing area of the object <NUM>. Also in the above-described variation, the contact detection unit <NUM> is attached to the carriage <NUM> as a liquid discharge unit. The liquid discharge apparatus <NUM> performs the ink discharge after the position measurement and the verification, thereby obtaining the above-described effect according to the present disclosure.

Next, other examples to which the present invention is applied are described with reference to <FIG>. r According to an example not covered by the appended claims, the present disclosure can also be applied to an unmanned aerial vehicle <NUM> such as a drone illustrated in <FIG>. The unmanned aerial vehicle <NUM> includes a detector <NUM> such as a rangefinder mounted thereon and controls the position of the unmanned aerial vehicle <NUM> based on a detection result of the detector <NUM>. The unmanned aerial vehicle <NUM> further includes a liquid discharge unit <NUM> including a head that discharges liquid such as ink. Liquid stored in a liquid tank <NUM> is supplied to the liquid discharge unit <NUM> via a tube <NUM>. The unmanned aerial vehicle <NUM> causes the head of the liquid discharge unit <NUM> to discharge the liquid toward an object <NUM> (a wall of a building in the present embodiment) based on the position controlled as described above to applies the liquid to an area to be painted P of the object <NUM>.

According to an example not covered by the appended claims, the present disclosure can also be applied to an unmanned vehicle <NUM> such as a wall climbing robot illustrated in <FIG>. The unmanned vehicle <NUM> drives rollers <NUM> while sucking the object <NUM> (the wall of the building in the present embodiment) at the bottom of the unmanned vehicle <NUM> to move on the object <NUM>. The unmanned vehicle <NUM> includes a liquid discharge unit <NUM> including a head that discharges liquid such as ink. Liquid stored in a liquid tank <NUM> is supplied to the liquid discharge unit <NUM> via a tube <NUM>. The unmanned vehicle <NUM> causes the head of the liquid discharge unit <NUM> to discharge the liquid toward the object <NUM> (the wall of the building in the present embodiment) to applies the liquid to an area to be painted P of the object <NUM>.

According to an example not covered by the appended claims, the present disclosure can also be applied to a coating robot <NUM> illustrated in <FIG> that coats, for example, a body of an automobile. The coating robot <NUM> includes a robot arm <NUM> that is freely movable like a human arm by a plurality of joints, and further includes a liquid discharge unit <NUM> including a head that discharges liquid at a distal end of the robot arm <NUM>. The robot arm <NUM> includes a three-dimensional (3D) sensor <NUM> near of the liquid discharge unit <NUM>. The coating robot <NUM> having an appropriate number of axes such as five, six, or seven axes can be used. The coating robot <NUM> detects the position of the liquid discharge unit <NUM> relative to the object <NUM> (the body of the automobile in the present embodiment) by the 3D sensor <NUM>, and moves the robot arm <NUM> based on the detection result to coat the object <NUM>.

According to an example not covered by the appended claims, the present disclosure can also be applied to an apparatus <NUM> illustrated in <FIG> that discharges liquid to manufacture an electrode, for example. <FIG> is a schematic view of the apparatus <NUM> that manufactures a negative electrode used for an electrochemical element such as a primary battery, a secondary battery, or a capacitor. This apparatus <NUM> includes a liquid discharge unit <NUM> including a head that discharges liquid. The liquid is discharged to an object <NUM> (a negative electrode substrate in the present embodiment) on a stage <NUM> by an inkjet method. A liquid tank <NUM> stores a liquid composition 900A for forming a negative electrode composite layer <NUM>, and the liquid composition 900A is supplied from the liquid tank <NUM> to the liquid discharge unit <NUM> via a tube <NUM>.

As illustrated in <FIG>, the liquid composition 900A may be circulated in the apparatus <NUM>. In <FIG>, an external tank <NUM> is connected to the liquid tank <NUM> via a valve 960A, and the liquid tank <NUM> is connected to the liquid discharge unit <NUM> via a valve 960B. Further, the liquid discharge unit <NUM> is connected to a pump <NUM> via a valve 960C, and the pump <NUM> is connected to the liquid tank <NUM>. In the above-described configuration, the apparatus <NUM> controls the flow of the liquid composition 900A with the pump <NUM> and the valves 960B and 960C to circulate the liquid composition 900A, which is stored in the liquid tank <NUM>, in the apparatus <NUM>.

As described above, the apparatus <NUM> includes the external tank <NUM> and the valve 960A. The apparatus <NUM> controls the valve 960A to supply the liquid composition 900A from the external tank <NUM> to the liquid tank <NUM> of the apparatus <NUM> when the liquid composition 900A to be discharged decreases. As illustrated in <FIG>, the object <NUM> (the negative electrode substrate) is placed on the stage <NUM> that is heatable, and the liquid composition 900A is discharged onto the object <NUM>. At this time, the stage <NUM> may be moved relative to the liquid discharge unit <NUM>, or the liquid discharge unit <NUM> may be moved relative to the object <NUM>. The stage <NUM> heats and dries the liquid composition 900A on the object <NUM>, thereby forming the negative electrode composite layer <NUM>.

Note that drying is not limited to heating on the stage <NUM>. For example, a drying device provided separately from the stage <NUM> may be used. The drying device is not particularly limited and may be appropriately selected as long as the drying device does not directly contact the liquid composition 900A. For example, a resistance heater, an infrared heater, a fan heater, or a blower can be used as the drying device. A plurality of drying devices may be provided.

The negative electrode used for the electrochemical element can also be manufactured using an apparatus <NUM> illustrated in <FIG>. In the apparatus <NUM>, a band-shaped object <NUM> (the negative electrode substrate in the present embodiment) made of stainless steel, copper or the like is wound around a cylindrical core, and the object <NUM> is loaded on a feed roller 980A and a winding roller 980B such that the surface of the object <NUM> on which the negative electrode composite layer <NUM> is to be formed faces upward. As the feed roller 980A and the winding roller 980B rotate counterclockwise, the object <NUM> moves from right to left in <FIG>. The liquid tank <NUM> stores the liquid composition 900A for forming the negative electrode composite layer <NUM>, and the liquid composition 900A is supplied from the liquid tank <NUM> to the liquid discharge unit <NUM> via the tube <NUM>. The liquid discharge unit <NUM> is disposed above the object <NUM> between the feed roller 980A and the winding roller 980B. A plurality of liquid discharge units <NUM> may be provided in a direction substantially parallel or substantially perpendicular to the conveyance direction of the object <NUM>.

The feed roller 980A and the winding roller 980B convey the object <NUM> carrying the liquid composition 900A to a drying device <NUM>. As a result, the liquid composition 900A on the object <NUM> is dried to form the negative electrode composite layer <NUM>, thereby forming a negative electrode <NUM> in which the negative electrode composite layer <NUM> is bonded onto the object <NUM> as the negative electrode substrate. Thereafter, the negative electrode <NUM> is cut into a desired size by punching or the like. The drying device <NUM> is not particularly limited and may be appropriately selected as long as the drying device <NUM> does not directly contact the liquid composition 900A. For example, a resistance heater, an infrared heater, or a fan heater can be used as the drying device <NUM>. Note that the drying device <NUM> may be provided above or below the object <NUM>, and a plurality of drying devices <NUM> may be provided.

In the apparatuses <NUM> and <NUM> that manufacture the negative electrode used for the electrochemical element as described above, an inkjet method is preferable in that a liquid can be applied to an aimed portion of the object <NUM> below the liquid discharge unit <NUM>. In addition, the inkjet method is preferable because the surfaces of the object <NUM> (the negative electrode substrate) and the negative electrode composite layer <NUM>, which are in contact with each other, can be bonded to each other. Further, the inkjet method is preferable because the film thickness of the negative electrode composite layer <NUM> can be formed evenly.

In the above description, the apparatus that manufactures the negative electrode used for the electrochemical element has been described as an example, but the present disclosure can also be applied to an apparatus that manufactures a positive electrode. When the positive electrode is manufactured, a positive electrode substrate is used as the object <NUM> instead of the negative electrode substrate, and a liquid composition for forming a positive electrode composite layer is used instead of the liquid composition 900A for forming the negative electrode composite layer <NUM>.

The following aspects <NUM> to <NUM> of the present disclosure can provide the following advantages.

According to Aspect <NUM>, the liquid discharge apparatus <NUM> includes the carriage70 (an example of a liquid discharge unit) and the contact detection unit <NUM> (an example of a contact detection unit). The carriage <NUM> has the nozzle <NUM> (an example of a liquid discharge port) from which ink (an example of a liquid) is discharged toward the object <NUM> (an example of an object on which an image is drawn). The carriage <NUM> is movable along at least one of the X-axis (an example of a first axis) and the Y-axis intersecting the X-axis (an example of a second axis intersecting the first axis), and movable along the Z-axis intersecting the X-axis and the Y-axis (an example of a third axis intersecting the first axis and the second axis). The Z-axis is parallel to the direction in which ink is discharged from the nozzle <NUM> toward the object <NUM>. The contact detection unit <NUM> detects contact of the carriage <NUM> with the object <NUM>. The contact detection unit <NUM> is detachably attached to the carriage <NUM>.

According to Aspect <NUM>, the liquid discharge apparatus <NUM> can be provided that prevents the carriage <NUM> from being damaged while moving the carriage <NUM> relative to the object <NUM>.

According to Aspect <NUM>, in Aspect <NUM>, the contact detection unit <NUM> includes the push switches <NUM> (an example of a position detector) that detect the position of the object <NUM> relative to the carriage <NUM> (i.e., position detection).

According to Aspect <NUM>, in Aspect <NUM> or <NUM>, the contact detection unit <NUM> includes the detection plates 215a and 215b (an example of a collision object detector) that detect a collision object on the object <NUM>, which may collide with the carriage <NUM> (i.e., collision object detection).

According to Aspect <NUM> and Aspect <NUM>, the position detection and the collision object detection can be performed with a simple configuration.

According to Aspect <NUM>, in any one of Aspects <NUM> to <NUM>, the contact detection unit <NUM> includes the first detector <NUM> (an example of a first component) detachably attached to the carriage <NUM> and the second detector <NUM> (an example of a second component) detachably attached to the first detector <NUM>, and performs at least one of the position detection and the collision object detection in response to movement of the first detector <NUM> and the second detector <NUM>.

According to Aspect <NUM>, in any one of Aspects <NUM> to <NUM>, the second detector <NUM> is movable parallel to a movement direction of the carriage <NUM> relative to the first detector <NUM>.

According to Aspect <NUM> and Aspect <NUM>, the single contact detection unit <NUM> can perform different types of detection (i.e., the position detection and the collision object detection).

According to Aspect <NUM>, in any one of Aspects <NUM> to <NUM>, the first detector <NUM> and the second detector <NUM> are attached to each other by the magnets <NUM> and <NUM> (an example of a magnetic force).

According to Aspect <NUM>, the second detector <NUM> can be easily positioned relative to the first detector <NUM>.

According to Aspect <NUM>, in any one of Aspects <NUM> to <NUM>, the contact detection unit <NUM> includes the push switches <NUM> and the detection plates 215a and 215b. The push switches <NUM> detect the position of the object <NUM> relative to the carriage <NUM> as the second detector <NUM> moves relative to the first detector <NUM> along the Z-axis. The detection plates 215a and 215b detect a collision object on the object <NUM> as the second detector <NUM> moves relative to the first detector <NUM> along at least one of the X-axis and the Y-axis. The push switches <NUM> and the detection plates 215a and 215b forms a series connection circuit. When the second detector <NUM> does not move in any of the X-axis, the Y-axis, and the Z-axis, the contact detection unit <NUM> outputs a signal indicating that the series connection circuit is in an electrically conductive state.

According to Aspect <NUM>, the liquid discharge apparatus <NUM> can also detect the attachment state of the first detector <NUM> and the second detector <NUM> to the carriage <NUM>.

According to Aspect <NUM>, in any one of Aspects <NUM> to <NUM>, the contact detection unit <NUM> has the detection face 220a (an example of a detection face) that contacts the object <NUM> to detect a position of the object <NUM> relative to the carriage <NUM>. The detection face 220a is larger in area than a liquid discharge face 302a (an example of a liquid discharge face) of the nozzles <NUM>.

According to Aspect <NUM>, a wide range can be detected at a time, and the position detection can be completed in a short time for the flat object <NUM>.

According to Aspect <NUM>, in any one of Aspects <NUM> to <NUM>, the contact detection unit <NUM> has the detection face 220a that contacts the object <NUM> to detect a position of the object <NUM> relative to the carriage <NUM>. The detection face 220a is equivalent in area to a liquid discharge face 302a of the nozzles <NUM>.

According to Aspect <NUM>, the position of the object <NUM> can be accurately detected at an interval corresponding to the width of the head <NUM> used for actual ink discharge.

According to Aspect <NUM>, in any one of Aspects <NUM> to <NUM>, the contact detection unit <NUM> has the detection face 220a that contacts the object <NUM> to detect a position of the object <NUM> relative to the carriage <NUM>. The detection face 220a is smaller in area than a liquid discharge face 302a of the nozzles <NUM>.

According to Aspect <NUM>, the position of the object <NUM> can be finely detected, thereby preventing a collision object on the object <NUM> from being overlooked.

According to Aspect <NUM>, in any one of Aspects <NUM> to <NUM>, the string-shaped component <NUM> (an example of a fall prevention component) that prevents the second detector <NUM> from falling from the first detector <NUM> is provided between the first detector <NUM> and the second detector <NUM>.

According to Aspect <NUM>, even when the second detector <NUM> is detached from the first detector <NUM>, the string-shaped component <NUM> can prevent the second detector <NUM> from falling off and from being damaged or lost.

Claim 1:
A liquid discharge apparatus (<NUM>) comprising:
a liquid discharge unit (<NUM>) having a liquid discharge port (<NUM>) from which a liquid is discharged toward an object (<NUM>), the liquid discharge unit (<NUM>) being movable along at least one of a first axis and a second axis intersecting the first axis and movable along a third axis intersecting the first axis and the second axis, the third axis being parallel to a direction in which the liquid is discharged from the liquid discharge port (<NUM>) toward the object (<NUM>); and
a contact detection unit (<NUM>) detachably attached to the liquid discharge unit (<NUM>),
wherein the contact detection unit (<NUM>) includes:
a first component (<NUM>) configured to be detachably attached to the liquid discharge unit (<NUM>); and
a second component (<NUM>) configured to be detachably attached to the first component (<NUM>), and
wherein the contact detection unit (<NUM>) is configured to perform at least one of a position detection and a collision object detection in response to movement of the first component (<NUM>) and the second component (<NUM>),
wherein the contact detection unit (<NUM>) includes:
a position detector (<NUM>) configured to detect a position of the object (<NUM>) when the object is at the position of the liquid discharge unit (<NUM>) along the first axis and the second axis as the second component (<NUM>) moves relative to the first component (<NUM>) along the third axis; and
a collision object detector (<NUM>) configured to detect a collision object on the object (<NUM>) to collide with the liquid discharge unit (<NUM>) as the second component (<NUM>) moves relative to the first component (<NUM>) along at least one of the first axis and the second axis,
wherein the position detector (<NUM>) and the collision object detector (<NUM>) are configured to form a series connection circuit which is an electrically non-conductive state when the second component (<NUM>) moves along any of the first, second and third axis, and
wherein the contact detection unit (<NUM>) is configured to output a signal indicating that the series connection circuit is in an electrically conductive state, when the second component (<NUM>) does not move along any of the first axis, the second axis, and the third axis,
the contact detection unit (<NUM>) includes a position detector (<NUM>) configured to detect a position of the object (<NUM>) along the third axis relative to the liquid discharge unit (<NUM>).