JPH09226201A - Printer - Google Patents

Abstract

(57) Abstract: Even a sensor including a pair of a light emitting element and a light receiving element detects the position of the carriage at both ends and accurately controls the moving direction. SOLUTION: A first non-scaling portion 30a having a light-transmitting property and a second non-scaling portion 30b having a light-shielding property are provided at both ends of a scaling portion SC of a strip-shaped encoder member 30. When the sensor provided on the carriage is at the position "C5" corresponding to the second non-scaling portion 30b, the carriage is moved in the backward movement direction RD to the boundary "C4" between the light transmitting portion and the light shielding portion, and then the scaling portion. SC
Until the width of the translucent part that exceeds the width Lw of the translucent part of
It moves in the backward direction RD, and the vicinity of the boundary between the scaling unit SC and the first non-scaling unit 30a is set as the origin position “C0”. When the carriage is at the position “C1” corresponding to the first non-scaling portion 30a, after moving to the adjacent light shielding portion 30c in the forward movement direction FD, the backward movement direction R is the same as above.
Move to D and set the origin position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer,
In particular, the present invention relates to a structure in which an encoder member is used to detect the moving position of a carriage equipped with a recording head.

[0002]

2. Description of the Related Art Conventionally, as a printer, for example, while ejecting ink from a plurality of ejection nozzles provided in a recording head, a carriage equipped with the recording head is moved in the printing direction to record an image in a dot pattern on a recording paper. In an ink jet recording apparatus configured to print on, a circular encoder disk is attached to a carriage drive motor that moves and drives a carriage, and a plurality of slits formed in a radial pattern on the encoder disk are composed of a light emitting element and a light receiving element. The carriage is configured to be read by a photo sensor for detecting the moving position, and a control device including a 1-chip CPU or the like detects the moving position of the carriage by using a detection signal (pulse signal) output from the photo sensor. Feed the drive motor to the specified moving speed. Tsu is adapted to click control.

By the way, in this kind of ink jet recording apparatus, a photo sensor for detecting an origin position different from the photo sensor for detecting the moving position is separately provided, and after the power is turned on, the carriage is provided on either the left or right end portion of its printing area. The origin position of the carriage is set based on the detection signal from the origin position detecting photosensor. Here, by providing a photo sensor for detecting the origin position in addition to the photo sensor for detecting the moving position, the cost of the inkjet recording apparatus becomes high. Therefore, recently, a common photo sensor is used to detect the moving position of the carriage. And the origin position detection are combined,
Various printers have been proposed to reduce the cost.

For example, in Japanese Unexamined Patent Publication No. 7-214857, a scaling portion in which a plurality of vertical lines are printed on a scale at a fine pitch with a paint, and a scaling portion formed at a part near the left end of the scaling portion A translucent scale made of a belt-shaped transparent resin plate having a non-scaling portion printed significantly wider than the width of the vertical line of the section is arranged parallel to the platen, and the carriage drive motor is rotated to drive the carriage to a predetermined position. When the sensor signal from the photo sensor attached to the carriage moves in the moving direction of, and remains unchanged for a predetermined time corresponding to the non-scaling part, the origin position of the carriage is detected while the scaling part is supported. A serial printer has been proposed which detects the moving position of the carriage on the basis of the received light pulse. .

[0005]

In both of the above-mentioned conventional devices, it is usual that the photosensor is provided with two pairs of light emitting elements and light receiving elements with a phase difference in order to determine the moving direction of the carriage. Is. In this case, since it is costly, it may be possible to configure the light emitting element and the light receiving element only in a pair. Then, in the latter conventional example, as described above, the moving position of the carriage is arranged on the translucent scale. A scaling unit for detection and a non-scaling unit for detecting the origin position of the carriage are formed, and the origin position of the carriage is detected by moving the carriage in a predetermined direction. If the carriage is located on the right side of the non-scaling section, the origin position can be detected normally, but if the carriage corresponds to the non-scaling section or is located on the left side of the non-scaling section. The carriage drive motor in the direction of moving away from the non-scaling part and colliding with the side wall plate of the main body frame, causing the carriage drive motor to step out. So must the direction reversed. At this time, there is a problem that noise is generated when the side plate of the main body frame collides.

An object of the present invention is to provide a printer capable of detecting the position of a carriage and accurately controlling the movement of the carriage.

[0007]

According to a first aspect of the present invention, there is provided a printer comprising: a print head; a carriage having the print head mounted thereon; and a carriage drive means for driving the carriage to reciprocate in a printing direction. In order to detect the moving position, an encoder member having a scaling part in which a light-transmitting part and a light-shielding part are alternately formed in a fine scale is provided on the printer body side, and the carriage has a light-transmitting part and a light-shielding part. An optical sensor for generating a corresponding detection signal is provided, and one end side portion and the other end side portion, which are detached on both sides of the scaling portion of the encoder member, are provided.
A first non-scaling section and a second section having mutually different optical characteristics
The non-scaling parts are formed respectively.

To explain the operation, the encoder member provided on the printer body side is provided with a scaling portion in which light-transmitting portions and light-shielding portions are alternately formed in a fine scale, and both sides of the scaling portion are formed. Since the first non-scaling portion and the second non-scaling portion having mutually different optical characteristics are formed on the one end side portion and the other end side portion which are separated from each other, respectively, the optical sensor provided on the carriage allows
Since the first non-scaling portion and the second non-scaling portion can be discriminated from each other based on the optical characteristics and which of the non-scaling portions they are facing can be discriminated, the carriage can be moved so as not to collide with the main body frame. . Further, at the time of printing, the movement position of the carriage can be detected by the detection signal generated from the optical sensor corresponding to the light transmitting portion and the light shielding portion which are formed in the scaling portion and have a fine scale.

A printer according to a second aspect is the printer according to the first aspect, wherein the scaling portion is formed in a range corresponding to a print area. Explaining the operation, the same operation as in claim 1 is achieved, but since the scaling portion is formed in the range corresponding to the printing area, it is necessary to additionally form the light transmitting portion and the light shielding portion in the form of microscales. Therefore, the manufacturing process of the encoder member can be simplified and the manufacturing cost can be reduced.

According to a third aspect of the invention, in the invention of the second aspect, the first non-scaling portion is a translucent strip-shaped portion, and the second non-scaling portion is a light-shielding strip-shaped portion. The operation is the same as that of claim 2, but the first non-scaling portion is a band-shaped portion having a light-transmitting property, and the second non-scaling portion is a band-shaped portion having a light-shielding property, so that its optical characteristics are Because of the difference, the first non-scaling portion and the second non-scaling portion can be easily identified and detected by the optical sensor provided on the carriage.

A printer according to a fourth aspect is the printer according to the second aspect, wherein the first non-scaling portion is arranged in the longitudinal direction of the encoder member and has a light-transmitting first belt-like portion and a light-shielding second belt-like portion. And the second non-scaling part is a band-shaped part having a light-transmitting property or a light-blocking property different from that of the first band-shaped part and the second band-shaped part on the end side of the encoder member.

Explaining the operation, the same operation as in claim 2 is achieved, but the first non-scaling portion is arranged in the longitudinal direction of the encoder member and has a light-transmitting first strip portion and a second light-shielding portion. Since it is composed of the strip-shaped portion, the detection widths of the first strip-shaped portion and the second strip-shaped portion are larger than the detection widths of the translucent portion and the light-shielding portion of the scaling portion. The boundary position between the first non-scaling part and the carriage can be set to the carriage origin position. Furthermore, since the second non-scaling portion is a belt-shaped portion having a light-transmitting property or a light-shielding property different from that of the first belt-shaped portion and the second belt-shaped portion on the end side of the encoder member, the same as in claim 2. Further, the carriage can be moved so as not to collide with the main body frame and set to the origin position.

According to a fifth aspect of the invention, in the printer of the third or fourth aspect, the printer receives the detection signal of the optical sensor and determines the boundary position between the first non-scaling section or the second non-scaling section and the scaling section. An origin position setting means for detecting and setting the origin position of the carriage is provided. Explaining the operation, the same operation as in claim 3 or claim 4 is achieved, but the origin position setting means receives the detection signal of the optical sensor and receives the detection signal from the first non-scaling section or the second non-scaling section and the scaling section. Since the boundary position is detected and the carriage origin position is set, the carriage origin position setting is simplified.

A printer according to a sixth aspect of the present invention is the printer according to any one of the first to fifth aspects, wherein the carriage moving means detects the encoder detected by an optical sensor in at least the first drive at the time of initial setting. The moving direction of the carriage is changed according to the optical characteristics of the members. Explaining the operation, the same operation as that of any one of claims 1 to 5 is achieved, but the optical characteristics of the encoder member detected by the optical sensor at least at the first drive at the time of initial setting, for example, of the scaling unit. Since the moving direction of the carriage is changed according to the light transmitting portion, the light shielding portion, or the first non-scaling portion or the second scaling portion, the first non-scaling portion and the second scaling portion are located at both ends. Due to the difference in the optical characteristics of the parts, it is possible to realize the movement of the carriage in the direction in which it does not collide with the main body frame.

According to a seventh aspect of the present invention, in the printer according to any one of the first to sixth aspects, the origin position of the carriage is based on the substantially boundary position between the scaling portion and both non-scaling portions of the encoder member. It further comprises control means for setting. Explaining the operation, the same operation as in any one of claims 1 to 6 is achieved, but the origin position of the carriage is set based on the substantially boundary position between the scaling part and both non-scaling parts of the encoder member. Therefore, the origin position of the carriage can be set without using a special origin detecting means.

According to an eighth aspect of the present invention, in the invention according to any one of the first to seventh aspects, the optical sensor includes only a pair of a light emitting element and a light receiving element. Explaining the operation, the same operation as any one of claims 1 to 7 is achieved, but due to the difference in the optical characteristics of the first non-scaling portion and the second scaling portion, a pair of light emitting element and light receiving element are received. Even with only the element, it is possible to accurately identify at which position the carriage is located at both ends, and it is possible to realize cost reduction.

A printer according to a ninth aspect is the printer according to any one of the first to eighth aspects, wherein the recording head is an ink jet type head for ejecting ink droplets toward a recording medium. Explaining the operation, claim 1
The same operation as in any one of claims 8 to 8 is achieved, but since the recording head is an inkjet type head, an image can be printed by ejecting ink droplets toward the recording medium.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. The present embodiment is a case where the present invention is applied to a carriage drive control device provided in an inkjet recording device that ejects ink contained in a detachably mounted ink cartridge from a recording head to print on recording paper. is there. First, the inkjet recording apparatus 1 will be described. As shown in FIG.
Basically, in the main body frame 3 provided in the main body cover 2,
The rubber platen 10, the carriage drive mechanism 20 for driving the carriage 21, and the ink ejection mechanism 40 for ejecting the recording ink contained in the ink cartridge 44 onto the recording paper P are provided.

As shown in FIGS. 1 and 2, the platen 10 is disposed in the left-right direction, and the platen shaft 11 has side wall plates 3a, 3 of the body frame 3 at both left and right ends thereof.
The platen gear 12 is mounted on the left end of the platen shaft 11 so as to be rotatably supported by the respective members c. Then, the side wall plate 3c is provided with a first member that meshes with the platen gear 12.
A composite gear 13 having a gear 14 and a second gear 15 is rotatably supported, and a drive gear 16 meshing with the second gear 15 is a feed motor 17 fixed to a side wall plate 3c.
Mounted on the motor shaft of. That is, when the feed motor 17 is driven in the predetermined rotation direction and the drive gear 16 rotates, the platen 10 is driven to rotate in the predetermined paper feed direction via the composite gear 13 and the platen gear 12.

Next, regarding the carriage driving mechanism 20,
A description will be given based on FIGS. A carriage 21 is horizontally arranged on the front side of the platen 10, and the carriage 21 is arranged at its rear end portion in parallel with the platen 10 and supported by the body frame 3.
Is supported by the guide rail portion 3d at the front end of the main body frame 3 so as to be movable in the left and right directions.

On the other hand, a driven pulley 23 is rotatably supported by the side wall plate 3b at the left end of the moving range of the carriage 21, and a drive shaft of a carriage drive motor 25 comprising a stepping motor at the right end thereof. Is provided with a drive pulley 24, and an endless timing belt 26 is stretched over both pulleys 23 and 24, and is connected to the timing belt 26 at the lower end of the carriage 21. Then, when the carriage drive motor 25 is rotationally driven by the drive pulse (see FIG. 3), the carriage 21 moves to the guide rod 22 and the guide rail portion 3d through the pulleys 23 and 24 and the timing belt 26. It is supported and driven to reciprocate in the scanning direction parallel to the platen 10, that is, in the forward direction FD (right direction) and the backward direction RD (left direction).

Here, below the carriage 21, FIG.
As shown in FIG. 3, a strip-shaped encoder member 30 made of a thin film and extending in the left-right direction is provided horizontally, and left and right end portions thereof are fixed to side wall plates 3a, 3b, respectively. Then, in the encoder member 30, a scaling portion SC is formed in the central portion corresponding to the printing range, and a non-scaling portion (first non-scaling portion) which is a band-shaped portion having a predetermined width and having a light-transmitting property. Equivalent to)
A non-scaling portion (corresponding to a second non-scaling portion) 30a is formed at the left end portion (corresponding to one end side portion) thereof and has a predetermined width and is a black-printed strip-shaped portion having a light shielding property. 30b is formed at the right end portion (corresponding to the other end side portion).

Further, in the scaling portion SC corresponding to the print area between the non-scaling portion 30a and the non-scaling portion 30b, the light shielding portion 30c printed in black having a predetermined width Hw and the transparent portion having a predetermined width Lw are provided. Translucent part 3
0d are alternately formed in a fine scale. And
A photosensor 31 (see FIG. 4), which is a single-phase optical sensor including only a pair of light emitting element and light receiving element, is attached to the lower side of the carriage 21 so as to face the encoder member 30.

That is, the photo sensor 31 outputs an "H" level signal corresponding to the non-scaling unit 30b and an "L" level signal corresponding to the non-scaling unit 30a. Further, the carriage 21
When the carriage 21 moves, the photo sensor 31 includes an "H" level signal corresponding to the light shielding portion 30c and an "L" level signal corresponding to the light transmitting portion 30d.
The number of detected pulse signals (corresponding to a detection signal) proportional to the movement amount of (1) is output. Here, since this detection pulse signal is also used for the ejection control that determines the ejection timing for ejecting the ink from the recording head 42, the light shielding portion 30c and the light transmitting portion 30d are 1/180 inch (about
0.14mm) each width is set.

Here, the non-scaling portion 30b is set to a width of a predetermined multiple (for example, 500 times) of the width Hw of the light shielding portion 30c, and the non-scaling portion 30a is set to the light transmitting portion 3.
The width is set to be a predetermined value (for example, 500 times) or more of the width Lw of 0d. On the other hand, the width Hw of the light-shielding portion 30c and the width Lw of the light-transmitting portion 30d are the moving distance of the carriage 21 by the carriage driving motor 25 that is rotationally driven by a predetermined driving pulse number "N1" (for example, four driving pulses). Further, the width of the non-scaling unit 30a depends on the carriage drive motor 25 that is rotationally driven by a predetermined drive pulse number "N2" (for example, a drive pulse number of about 500 times the drive pulse number "N1"). The width of the non-scaling portion 30b corresponds to the moving distance of the carriage 21, and the width of the non-scaling portion 30b is a predetermined drive pulse number "N3" (for example, about 50 of the drive pulse number "N1").
This corresponds to the movement distance of the carriage 21 by the carriage drive motor 25 that is rotationally driven by 0 times the number of drive pulses.

Next, the ink ejecting mechanism 40 for ejecting ink on the recording paper P to print will be described with reference to FIGS. 1 and 2. A box-shaped head holder 41 having an open top and front is mounted on the carriage 21. A recording head 4 for ejecting ink, in which a plurality of ejection nozzles are formed on a standing wall portion 41a of the head holder 41.
2 is provided, and the recording head 42 is provided with a connecting cylinder portion 43 which is integrally formed by inserting the standing wall portion 41a.

An ink cartridge 44 containing an ink absorber containing recording ink is removably mounted on the head holder 41, and the front end of the connecting cylinder 43 is supplied to the ink cartridge 44. It is adapted to come into contact with the ink absorber through an opening (not shown). As a result, the ink in the ink cartridge 44 is supplied to the recording head 42 via the connecting cylinder portion 43,
Ink is ejected from the ejection nozzles of the recording head 42 and printed on the recording paper P.

Next, the control system of the ink jet recording apparatus 1 is constructed as shown in the block diagram of FIG. The first control unit 50 controls the print control circuit 50a that outputs an ejection drive signal for executing ink ejection from a plurality of ejection nozzles to the head drive circuit 51, and the rise and fall of the pulse signal received from the photo sensor 31. The print control circuit 50a and the pulse signal detection circuit 50b are each configured as a so-called application specific integrated circuit (ASIC) including a hard logic circuit.

The print control circuit 50a is connected to a head drive circuit 51 for driving the recording head 42, and the pulse signal detection circuit 50b is configured to receive a pulse signal from the photo sensor 31. Here, the pulse signal detection circuit 50b including a hard logic circuit is provided with a pulse period calculation unit, and each time the pulse signal is received from the photo sensor 31, the latest “H” level time and “H” level time for one period. One period of time, which is the sum of the “L” level time, is sequentially detected and is output to the second control unit 55 as a speed signal.

Further, the first control unit 50 is connected to the second control unit 55 via a bus 52 such as a data bus, and the bus 52 is further connected to a ROM 53 and a RAM 54. The ROM 53 stores various control programs for image printing and a carriage initialization control control program, which will be described later and is unique to the present application. Also,
The RAM 54 is provided with an image data memory for storing the received image data, a memory for storing a count value indicating the carriage position, and various memories and buffers necessary for image printing.

Next, the second control unit 55 will be described. The second control unit 55 is a one-chip unit equipped with a peripheral input / output interface for performing image processing on the received image data and controlling various peripheral circuits. CPU, CPU
55a and a peripheral input / output interface 55b which is a so-called programmable peripheral interface (PPI). The PPI 55b has a carriage drive circuit 56 for driving the carriage drive motor 25, a drive circuit 57 for driving the feed motor 17, an operation panel 58 provided with a power switch, various switches, and an indicator lamp. And a paper sensor 59 for detecting the presence or absence of the recording paper P and the position of the leading edge of the recording paper P, and a communication interface 60 capable of receiving image data transmitted from an external electronic device 61 such as a host computer. ing. Where C
PU55a, ROM53 and RAM54 cooperate,
A carriage driving unit that drives the carriage to reciprocate, and a control unit that manages the carriage position and sets the origin position are configured.

Next, a routine for carriage initialization control performed by the second controller 55 of the ink jet recording apparatus 1 will be described with reference to the flowchart of FIG.
The reference numeral Si (i = 10, 11, 12, ...) Indicates each step. When the inkjet recording apparatus 1 is powered on, a reset signal output from the CPU 55a initializes each memory of the RAM 54 and simultaneously executes this control.

When this control is started, first, the count value J of the drive pulse number counter is cleared (S10). Next, from the pulse signal detection circuit 50b, the photo sensor 31
When the pulse signal detected in step S1 is read and the pulse signal is at the "H" level, that is, when the photo sensor 31 corresponds to the light shielding unit 30c or the non-scaling unit 30b (S11: Yes), the pulse signal is "L". Until the level is reached, the carriage drive motor 25 is reversely driven by one drive pulse, and the carriage 21 is moved in the backward direction by a small distance (S12, S11: Yes). That is, when this control is started and the carriage 21 is at the position corresponding to the non-scaling portion 30b, the carriage 21
Is moved in the returning direction RD so as not to collide with the side wall plate 3a.

When the pulse signal becomes "L" level (S11: No), the carriage drive motor 25 is normally driven by one drive pulse until the pulse signal becomes "H" level, and the carriage 21 is driven. Is moved in the forward direction FD by a small distance (S13, S14: No). That is, when this control is started and the carriage 21 is at the position corresponding to the non-scaling portion 30a, the carriage 2
1 is moved in the forward movement direction FD so as not to collide with the side wall plate 3b. Then, when the pulse signal becomes the "H" level (S14: Yes), that is, the carriage 21 is made to correspond to any one of the plurality of light transmitting parts 30d, and the carriage is carried out by the following S15 to S20. 21 is moved to a predetermined position at the right end of the non-scaling unit 30a, and that position is set as the origin position.

That is, the carriage drive motor 25 is reversely driven by one drive pulse (S15), and the count value J of the drive pulse number counter is incremented by one (S1).
6). When the pulse signal is at "H" level (S17: Yes), the count value J is cleared (S1
8), S15 and subsequent steps are repeatedly executed. By the way, when the pulse signal becomes "L" level (S17: No),
When the count value J is equal to or less than the drive pulse number "N1" (S19: No), S15 and thereafter are similarly executed. And
When the carriage 21 moves in the backward movement direction RD by a small distance in correspondence with the right end portion of the non-scaling portion 30a and the count value J becomes larger than the drive pulse number "N1" (S19: Yes), the carriage drive The motor 25 is driven forward by (J-1) drive pulse, and the carriage 21 is moved to the right end of the non-scaling portion 30a (S2
0) At that position, the count value J is set to 0 to be the origin position. Then, this control is terminated and the process returns to the main routine.

Next, the operation of the carriage initial setting control based on the above flow chart will be described with reference to FIG. When the carriage 21 is at the position "C5" corresponding to the non-scaling portion 30b, the carriage 21 is first moved to the position "C4" in the backward direction RD so as not to collide with the side wall plate 3a (S11: Yes, S12, S11: No), the boundary position between the non-scaling part 30a and the scaling part SC is detected (S13 to S20), and the position is moved to the origin position "C0" corresponding to this boundary position. Further, when the carriage 21 is at the position "C3" corresponding to one of the light shielding portions 30c of the scaling portion SC, after the carriage 21 is moved to the boundary portion with the light transmitting portion 30d adjacent to the backward movement side (S11: Yes, S12, S11: N
o), similarly moved to the origin position "C0".

Further, the carriage 21 has a scaling unit S.
At the position "C2" corresponding to any of the light-transmitting portions 30d of C, after moving to the boundary with the light-shielding portion 30c adjacent to the forward side (S11: No, S13, S14: Yes), similarly. It is moved to the origin position "C0". On the other hand, when the carriage 21 is at the position "C1" corresponding to the non-scaling portion 30a, first, the carriage 21 is moved to the boundary portion with the light shielding portion 30c adjacent to the forward side so as not to collide with the side wall plate 3b (S11: No). ,
(S13, S14: Yes), similarly, it is moved to the origin position "C0".

As described above, the encoder member 30 provided on the printer body side is provided with the scaling portions SC in which the light-transmitting portions 30d and the light-shielding portions 30c are alternately formed in a fine scale, and both sides of the scaling portions SC are provided. A non-scaling portion 30a, which is a strip-shaped portion having a light-transmitting property, and a non-scaling portion 30b, which is a strip-shaped portion having a light-shielding property, can be respectively identified on the one end side portion and the other end side portion which are separated from each other, based on optical characteristics. Since it is formed, the one photo sensor 31 provided on the carriage 21 moves the carriage 21 so as not to collide with the main body frame 3, and the boundary position between the scaling part SC and the non-scaling part 30a is set to the origin position of the carriage 21. Can be set.

At the time of printing, the moving position of the carriage 21 can be detected by the pulse signal (detection signal) generated from the photo sensor 31 corresponding to the scaling section SC. Further, since the scaling portion SC provided on the encoder member 30 is formed in the range corresponding to the print area, the translucent portion 30d and the light shielding portion 30c in the form of fine scales are not additionally formed, and the encoder is provided. The manufacturing process of the member 30 can be simplified and the manufacturing cost can be reduced.

By the way, the encoder member 30A is shown in FIG.
It may be configured as shown in FIG. That is, in the non-scaling portion 30a, a transparent strip portion 30e having a predetermined width and transparency, and a light-shielding strip portion that is continuous with the transparent strip portion 30e, has a predetermined width, and has a light blocking property, and is printed in black. Three
0f are formed side by side in the longitudinal direction. Here, the light-shielding band-shaped portion 30f is set to a width that is a predetermined multiple (for example, 400 times) of the width Hw of the light-shielding portion 30c, and the width of the non-scaling portion 30b is sufficiently larger than the width of the light-shielding band-shaped portion 30f. It is getting bigger. Further, the non-scaling unit 30b is
It is a band-shaped portion that is optically different from the transparent band-shaped portion 30e at the other end of the encoder member 30.

The width of the light-shielding strip portion 30f has a predetermined drive pulse number "N4" (for example, drive pulse number "N1").
Corresponding to the movement distance of the carriage 21 by the carriage drive motor 25 that is rotationally driven by about 400 times the driving pulse number), and the width of the non-scaling portion 30b is a predetermined driving pulse number “N5” (for example, driving pulse number). Carriage drive motor 25 that is rotationally driven by a driving pulse number larger than the number "N4" and about 500 times the driving pulse number "N1".
The length of the carriage 21 is equal to or larger than the moving distance of the carriage 21.

Next, the routine for the carriage initial setting control will be described with reference to the flowchart of FIG.
Reference numeral Si (i = 30, 31, 32, ...) Indicates each step. When the inkjet recording apparatus 1 is powered on, a reset signal output from the CPU 55a initializes each memory of the RAM 54 and simultaneously executes this control.

When this control is started, first, the above S10-
Similar to S12, S30 to S32 are executed. That is, the count value J of the drive pulse number counter is cleared (S3
0). Next, when the pulse signal from the pulse signal detection circuit 50b is read and the pulse signal is at the "H" level, that is, when the carriage 21 corresponds to the light shielding portion 30c, the light shielding band portion 30f, or the non-scaling portion 30b. (S31: Yes), until the pulse signal becomes "L" level, the carriage drive motor 25 is reversely driven by one drive pulse, and the carriage 21 is moved in the backward direction RD by a small distance (S32, S31). : Yes). That is, when this control is started and the carriage 21 is at the position corresponding to the non-scaling portion 30b, the carriage 21 is moved in the backward movement direction RD so as not to collide with the side wall plate 3a.

When the pulse signal is at the "L" level, that is, when the carriage 21 corresponds to the translucent portion 30d or the transmissive strip portion 30e (S31: No), the carriage drive motor 25 rotates forward by one drive pulse. Driven,
The carriage 21 is moved in the forward direction FD by a small distance (S33). That is, when this control is started and the carriage 21 is at the position corresponding to the transparent strip portion 30e, the carriage 21 is moved in the forward direction FD so as not to collide with the side wall plate 3b. Next, the count value J of the drive pulse number counter is incremented by 1 (S3
4) When the pulse signal is at "H" level (S35: Yes
), When the count value J is equal to or less than the number of drive pulses “N4” corresponding to the light-shielding band portion 30f (S36: No), S33.
The subsequent steps are repeatedly executed.

The count value J is the drive pulse number "N".
When the value becomes larger than 4 ”(S36: Yes),
The carriage drive motor 25 has a non-scaling section 30b.
Since it corresponds to the
The reverse drive is performed with the drive pulse number "N6" corresponding to the distance to the position corresponding to the light transmitting portion 30d adjacent to the right side of (S37). Next, when the pulse signal is at the "L" level (S40: No), the carriage drive motor 25 is reversely driven by one drive pulse until the pulse signal is switched to the "H" level, and the carriage 21 is moved by a small distance. Return direction R
Moved to D (S41, S40: No), pulse signal is "H"
When the level is switched, the origin position of the carriage 21 is set, the control is terminated, and the process returns to the main routine.

On the other hand, as a result of the normal rotation drive of the carriage drive motor 25, when the pulse signal is switched from the "H" level to the "L" level (S35: No), the count value J is the drive pulse number "N1". In the following cases (S38: No), since the carriage 21 corresponds to the light transmitting section 30d, the count value J is cleared (S39), and S33 and the subsequent steps are repeated. By the way, the carriage 21 is used as the light-shielding band 3
When the count value J is larger than the number of drive pulses "N1" when the pulse signal is switched to the "L" level while moving in the forward direction FD while corresponding to 0f (S38: Yes). , The carriage 21 is a light-shielding strip 30
Since it corresponds to the translucent portion 30d adjacent to the right side of f,
By S40 to S41, the robot is finally moved to the origin position.

Next, the operation of the carriage initial setting control based on the above flow chart will be described with reference to FIG. When the carriage 21 is at the position "C8" corresponding to the non-scaling portion 30b, the left end position "C" of the non-scaling portion 30b is first set so as not to collide with the side wall plate 3a.
After moving to the return direction RD up to 7 "(S31: Yes, S3
2, S31: No), when moved to the forward direction FD and moved to the position “C9” corresponding to the drive pulse number larger than the drive pulse number “N4” corresponding to the light-shielding strip portion 30f (S36). : Yes), it is moved to the transparent portion 30d (C4) adjacent to the right side of the light-shielding strip portion 30f (S37), and finally, the boundary position between the light-shielding strip portion 30f and the scaling portion SC, that is, the non-scaling portion 30a. And scaling unit S
The boundary position with C is detected (S40: No, S41, S40: Yes
), It is moved to the origin position “C0” corresponding to this boundary position.

Further, the carriage 21 has a scaling unit S.
At the position "C6" corresponding to any of the light-shielding portions 30c of C, after moving to the position "C9" as described above, it is finally moved to the origin position "C0". Further, when the carriage 21 is at the position "C5" corresponding to any of the light transmitting parts 30d of the scaling part SC, the position "C5" is the same as above.
After moving to "9", it is finally moved to the origin position "C0".

On the other hand, the carriage 21 has the light-shielding band portion 30.
At the position "C3" corresponding to f, the light-shielding band-like portion 3
After being moved to the left end position "C2" of 0f (S31: Yes,
S32, S31: No), and moved to the position "C4" corresponding to the light transmitting portion 30d adjacent to the right side of the light shielding band portion 30f (S4).
33 to S38: Yes), and finally moved to the origin position "C0". Further, when the carriage 21 is at the position "C1" corresponding to the light-transmissive strip 30e, it corresponds to the light-transmissive portion 30d adjacent to the right side of the light-shielding strip 30f so as not to collide with the side wall plate 3b. To the position "C4" (S31: No to S38: Yes), and finally the origin position "C0".
Moved to

Thus, the non-scaling unit 30a is
A light-transmissive band-shaped portion 30e having a light-transmitting property and a light-shielding band-shaped portion 30 having a light-shielding property that are arranged in the longitudinal direction of the encoder member 30
Since the non-scaling portion 30b is wider than the light-shielding strip portion 30f, the detection width of the light-transmitting strip portion 30e and the light-shielding strip portion 30f is the same as that of the scaling portion SC. Light portion 30d and light shielding portion 30c
Since the detection width of the non-scaling portion 30b is larger than the detection width of the light-shielding strip portion 30f, when the carriage is at the position of the light-shielding strip portion 30f in the initial state. , The side wall plate 3a can be moved, and the origin position can be detected without colliding with the side wall plate 3a.

Further, since the non-scaling portion 30b is composed of the light-transmissive strip portion 30e and the light-shielding strip portion 30f, the strip portion having a light-transmitting property or a light-shielding property different from the end portion side of the encoder member 30. The carriage 21 can be moved so as not to collide with the main body frame 3 and set to the origin position.

It should be noted that the origin position is a position that is moved leftward or rightward by a predetermined step from the boundary between the non-scaling portion 30a and the scaling portion SC, or the non-scaling portion 30a in the encoder member 30 is a band portion having a light shielding property. In addition, the non-scaling portion 30b is configured by a band portion having a light-transmitting property, and the determination of the "H" level and the "L" level in the carriage initial setting control is configured to be reversed, and the encoder member 30A is configured. The translucent band-shaped portion 30e and the light-shielding band-shaped portion 30f are provided on the left and right, and the non-scaling portion 30b is constituted by the translucent band-shaped portion. It is possible to make various changes based on the obvious technique. Further, it goes without saying that the present invention can be applied to various ink jet recording devices and various printers capable of color printing.

[0053]

According to the printer of the first aspect of the present invention, the encoder member provided on the printer body side is provided with the scaling portion in which the light-transmitting portions and the light-shielding portions are alternately formed in the form of minute scales, and the scaling portion is provided. Since the first non-scaling portion and the second non-scaling portion are formed so as to be distinguishable from each other on the one end side portion and the other end side portion that deviate on both sides of the, respectively, by the optical sensor provided on the carriage,
The carriage can be moved so as not to collide with the main body frame, and at the time of printing, the movement position of the carriage can be detected by the detection signal generated from the optical sensor corresponding to the scaling unit.

According to the printer of the second aspect, the same effect as that of the first aspect can be obtained, but since the scaling portion is formed in the range corresponding to the printing area, the light transmitting portion having a fine scale and the light shielding portion are formed. It is possible to simplify the manufacturing process of the encoder member and reduce the manufacturing cost without forming additional parts. According to the printer of claim 3,
Although the same effect as in claim 2 is obtained, the first non-scaling portion is a light-transmissive strip portion and the second non-scaling portion is a light-shielding strip portion. The first non-scaling portion and the second non-scaling portion can be easily identified and detected by the optical sensor provided on the carriage.

According to the printer of claim 4, the same effect as that of claim 2 is obtained, but the first non-scaling section is
A first light-transmitting member arranged in the longitudinal direction of the encoder member.
Since it is composed of the strip-shaped portion and the second strip-shaped portion having a light-shielding property, the detection width between the first strip-shaped portion and the second strip-shaped portion is larger than the detection width between the light-transmitting portion and the light-shielding portion of the scaling portion. Since they are respectively larger, the boundary position between the scaling unit and the first non-scaling unit can be set to the origin position of the carriage. Furthermore, since the second non-scaling portion is a belt-shaped portion having a light-transmitting property or a light-shielding property different from that of the first belt-shaped portion and the second belt-shaped portion on the end side of the encoder member, the same as in claim 2. In addition, the carriage can be moved so as not to collide with the body frame and set to the origin position.

According to the printer of the fifth aspect, the same effect as that of the third or fourth aspect can be obtained, but the origin position setting means receives the detection signal of the optical sensor, and the first non-scaling section or the second non-scaling section. Since the carriage origin position is set by detecting the boundary position between the non-scaling part and the scaling part, the carriage origin position setting is simplified.

According to the printer of the sixth aspect, the same effect as that of any one of the first to fifth aspects is obtained, but the encoder member detected by the optical sensor at least at the first driving at the time of initial setting. Since the carriage moving direction is changed in accordance with the optical characteristics of the carriage, the difference in the optical characteristics of the first non-scaling portion and the second scaling portion at the positions of both ends causes the carriage to be in a direction in which the carriage does not collide with the main body frame. It can be realized to move. According to the printer of the seventh aspect, the same effect as that of any one of the first to sixth aspects is obtained, but the carriage of the carriage is based on the substantially boundary position between the scaling portion and both non-scaling portions of the encoder member. Since the origin position is set, the origin position of the carriage can be set without using a special origin detecting means.

According to the printer of the eighth aspect, the same effect as that of any one of the first to seventh aspects is obtained, but the difference in the optical characteristic between the first non-scaling section and the second scaling section. Therefore, it is possible to accurately identify the position of the carriage at both ends with only one pair of the light emitting element and the light receiving element.
Cost reduction can be realized. According to the printer of the ninth aspect, the same effect as that of any one of the first aspect to the eighth aspect is obtained, but since the recording head is an inkjet type head, by ejecting ink droplets toward the recording medium. , Images can be printed.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a partial plan view of the inkjet recording apparatus.

FIG. 3 is an explanatory diagram showing an encoder member, each pulse, and a carriage position.

FIG. 4 is a block diagram of a control system of the inkjet recording apparatus.

FIG. 5 is a schematic flowchart of a routine for carriage initialization control.

FIG. 6 is a view corresponding to FIG. 3, in which a non-scaling portion is composed of a light-transmissive strip portion and a light-shielding strip portion according to the modification.

FIG. 7 is a flowchart of a routine for carriage initialization control according to a modification.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inkjet recording device 20 Carriage drive mechanism 21 Carriage 25 Carriage drive motor 30 / 30A Encoder member 30a Non-scaling part 30b Non-scaling part 30c Light-shielding part 30d Light-transmitting part 30e Light-transmitting strip part 30f Light-shielding strip part 31 Photosensor 42 Recording Head 55 Second control unit

Claims (9)

[Claims] 1. A printer comprising a recording head, a carriage on which the recording head is mounted, and a carriage driving means for driving the carriage to reciprocate in the printing direction. In order to detect the movement position of the carriage, a light transmitting section is provided. An optical sensor is provided on the main body of the printer, the encoder member having a scaling portion in which the light-shielding portion and the light-shielding portion are alternately formed in a minute scale, and at the same time, the carriage outputs detection signals corresponding to the light-transmitting portion and the light-shielding portion of the encoder member. And a first non-scaling portion and a second non-scaling portion having mutually different optical characteristics are formed on one end side portion and the other end side portion of the encoder member, which are located on both sides of the scaling portion of the encoder member, respectively. Printer. 2. The printer according to claim 1, wherein the scaling unit is formed in a range corresponding to a print area. 3. The printer according to claim 2, wherein the first non-scaling portion is a translucent strip-shaped portion, and the second non-scaling portion is a light-shielding strip-shaped portion. 4. The first non-scaling portion comprises a first strip-shaped portion having a light-transmitting property and a second strip-shaped portion having a light-shielding property, which are arranged in the longitudinal direction of the encoder member, and the second non-scaling portion is the first. The printer according to claim 2, wherein the printer comprises a strip-shaped portion having a light-transmitting property or a light-shielding property different from that of the end portion of the encoder member of the strip-shaped portion and the second strip-shaped portion. 5. A first signal receiving a detection signal of the optical sensor,
5. The printer according to claim 3, further comprising an origin position setting unit that detects a boundary position between the non-scaling unit or the second non-scaling unit and the scaling unit and sets an origin position of the carriage. . 6. The carriage moving means changes the moving direction of the carriage in accordance with an optical characteristic of the encoder member detected by the optical sensor in at least the first driving at the time of initial setting. Item 1
The printer according to claim 5. 7. The control means for setting the origin position of the carriage based on substantially the boundary position between the scaling portion and both non-scaling portions of the encoder member, according to any one of claims 1 to 6. The printer according to item 1. 8. The printer according to claim 1, wherein the optical sensor includes only a pair of a light emitting element and a light receiving element. 9. The printer according to claim 1, wherein the recording head is an inkjet type head that ejects ink droplets toward a recording medium.