JP2003145817A - Thermal transfer printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a rear end of a recording material from being stained through rubbing of an ink ribbon against the rear end of the recording material when a thermal head slips off the rear end of the recording material. SOLUTION: At printing, when it is detected that the rear end of the recording material transferred in a recording material path 2 by a transfer mechanism 3 reaches a preparation position Pu, the thermal head 5 butted against a platen 4 via the ink ribbon 7 is separated away from the platen 4 by a head holding mechanism.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer printer for printing by thermally melting ink of an ink ribbon and transferring it to a recording material.

[0002]

2. Description of the Related Art Conventionally, there is a thermal transfer printer in which a thermal head and a platen are opposed to each other via an ink ribbon. In such a thermal transfer printer, the ink applied to the film is melted by heating the ink ribbon with a thermal head, and the ink in the melted portion of the ink layer is conveyed between the ink ribbon and the platen. Printing is performed by transferring to a material.

In such a thermal transfer printer, in order to bring the ink ribbon into good contact with the entire surface of the recording material, there is provided an urging mechanism for urging the thermal head into contact with the platen.

By the way, when the thermal head is biased toward the platen to cause a deviation between the winding speed of the ink ribbon and the conveying speed of the recording material, the ink ribbon and the recording material are separated from each other. Since the recording material is rubbed and soiled, the thermal transfer printer described above winds up the ink ribbon during conveyance of the recording material regardless of whether printing is performed.

However, the unused ink ribbon may be wound up by winding up the ink ribbon regardless of the presence or absence of printing.

As a countermeasure against this, conventionally, there is a thermal transfer printer in which the thermal head is separated from the platen except in the printing area, and the ink ribbon is not wound in a state where the thermal head and the platen are separated from each other.

[0007]

Here, FIG. 13 shows the position of the recording material between the platen and the thermal head, the printing range, and the position of the thermal head during the printing process in the conventional thermal transfer printer. It is a timing chart which shows a relationship. As described above, in the thermal transfer printer in which the thermal head is constantly urged in the direction of contacting the platen, when the trailing edge of the recording material passes through the contact part between the thermal head and the platen (see Pe in FIG. 13). ), The thermal head slides down the trailing edge of the recording material and contacts the platen. Since the thermal head contacts the recording material via the ink ribbon, when the thermal head slides on the trailing edge of the recording material and contacts the platen, the trailing edge of the recording material strongly rubs against the ink ribbon. The ink in the rubbed portion is transferred to the recording material. For this reason, the rear end of the recording material is contaminated.

Further, in such a thermal transfer printer, since the thermal head is constantly urged in the direction of contacting the platen, the urging force of pressing the recording material to the platen acts on the recording material, and the platen side. Then, the transport force from the platen acts. For this reason, when an envelope formed by stacking two sheets of paper is used as the recording material, the leading end of the envelope in which the sheet positioned on the thermal head side and the sheet positioned on the platen side are integrated by bonding or the like When the portion passes through the contact portion between the thermal head and the platen, the misalignment between the sheets positioned on the thermal head side and the sheet positioned on the platen side is likely to occur. If the sheet positioned on the side of the thermal head and the sheet positioned on the side of the platen continue to be conveyed while the misalignment occurs, the envelope may be pulled and wrinkled.

On the other hand, as described above, in the thermal transfer printer in which the thermal head is separated from the platen except in the printing area, the envelope used as the recording material may be swollen. like,
Although the thermal head 102 and the platen 103 are separated, the expanded envelope 101 may come into contact with the ink ribbon 104. In such a thermal transfer printer 100, the ink ribbon 104 and the envelope 101 rub against each other and the envelope 101 becomes dirty.

The present invention provides a thermal transfer printer capable of preventing the rear end of the recording material from being soiled by rubbing the ink ribbon against the rear end of the recording material due to the thermal head sliding down the rear end of the recording material. The purpose is to get.

It is an object of the present invention to obtain a thermal transfer printer which can prevent the envelope from becoming dirty due to the envelope being rubbed against the ink ribbon.

[0012]

According to the present invention, a recording material path through which a recording material is guided, a transport mechanism for transporting the recording material in the recording material path, and a recording material path are arranged to face each other. A printing unit having a platen and a thermal head, a head holding mechanism that holds the thermal head in contact with and away from the platen, and an ink ribbon positioned between the platen and the thermal head can be wound up freely. The ribbon holding mechanism for holding and the trailing end of the recording material conveyed in the recording material path are located upstream of the contact position where the thermal head and the platen in the recording material path are in contact with each other in the recording material conveying direction. The trailing edge arrival determining means for determining whether or not the set preparation position has been reached, and the trailing edge arrival determining means, when printing by the printing unit, causes the trailing edge of the recording material to reach the preparing position. If it is determined that the comprises a head displacement means of separating from the platen to the thermal head by the head holding mechanism.

Therefore, when printing by the printing unit,
When the trailing edge arrival determining means determines that the trailing edge of the recording material transported in the recording material path by the transport mechanism has reached the preparation position, the thermal head is in contact with the platen via the ink ribbon. Is separated from the platen by the head holding mechanism.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described with reference to FIGS. The present embodiment is used by connecting to a host computer such as a personal computer, and based on print data transmitted from the host computer, to a thermal transfer printer that performs printing by transferring the ink of the ink ribbon to a recording material. An application example is shown.

FIG. 1 is a schematic view showing the structure of a thermal transfer printer according to the first embodiment of the present invention. The thermal transfer printer 1 includes a recording material path 2 through which a recording material is guided, a transport mechanism 3 that transports the recording material in the recording material path 2, a platen 4 and a thermal head 5 that are arranged to face each other via the recording material path 2. A print unit 6 having a print head, a head holding mechanism for holding the thermal head 5 in contact with and separating from the platen 4, and an ink ribbon 7 positioned between the platen 4 and the thermal head 5 held in a windable manner. Ribbon holding mechanism 8
Then, the trailing edge of the recording material conveyed in the recording material path 2 is set upstream of the contact position Pp where the thermal head 5 and the platen 4 in the recording material path 2 contact each other. The trailing edge arrival determining means for determining whether the trailing edge arrives at the preparation position Pu, and when the trailing edge arrival determining means determines that the trailing edge of the recording material has reached the preparation position Pu during printing by the printing unit 6. Head displacement means for separating the thermal head 5 from the platen 4 by a head holding mechanism,
It is equipped with.

Specifically, the recording material path 2 is a paper discharge position (not shown) through which the recording material after printing is discharged from a paper feeding position (not shown) that holds the recording material before printing via the printing unit 6. It is in communication with the location.

The transport mechanism 3 is provided in the recording material path 2 and transports the recording material held at the paper feeding position toward the paper discharging position. The transport mechanism 3 according to the present embodiment is provided with the recording material path 2
It is realized by a plurality of roller pairs that face each other with a gap between them. The transport mechanism 3 is not limited to the roller pair, but may be, for example, an endless belt (not shown) wound around the rollers. The transport mechanism 3 is rotationally driven by a platen motor 9 (see FIG. 2).

The platen 4 in the printing unit 6 is connected to a platen motor 9 (see FIG. 2) via a gear train (not shown), and is rotated in one direction by the platen motor 9. The thermal head 5 is a line thermal head in which a plurality of heating elements (not shown) are arranged on a line along the main scanning direction (the front and back direction of the paper surface in FIG. 1). The thermal head 5 is held by a head holding mechanism (not shown) that holds the thermal head 5 so that it can move toward and away from the platen 4. The head holding mechanism is the head solenoid 10
By switching ON / OFF (see FIG. 2), the thermal head 5 is selectively contacted with either the print position where the thermal head 5 contacts the platen 4 at the contact position Pp or the ribbon save position where the thermal head 5 separates from the platen 4. Located in. FIG. 1 shows a state in which the thermal head 5 is positioned at the print position, and it is assumed that the thermal head 5 of the present embodiment is normally positioned at the print position. The head holding mechanism has a biasing member (not shown) that biases the thermal head 5 positioned at the print position toward the platen 4.

The ribbon holding mechanism 8 has a ribbon holding shaft 11 and a ribbon winding shaft 12 for holding the ink ribbon 7 in a stretched state between the platen 4 and the thermal head 5. The ribbon holding mechanism 8 holds the ink ribbon 7 so that the ink layer faces the platen 4 side. The unused portion of the ink ribbon 7 is held by the ribbon holding shaft 11 in a roll shape. The ribbon take-up shaft 12 holds the used portion of the ink ribbon 7 in a roll shape.
The ribbon holding shaft 11 and the ribbon winding shaft 12 are arranged above the printing unit 6, respectively, and are rotatable at the arranged positions. Ribbon holding shaft 11
Is connected to the ribbon delivery motor 23 via a gear train (not shown). The ribbon winding shaft 12 is connected to a ribbon winding motor 24 via a gear train (not shown).

Ribbon holding shaft 11 and ribbon winding shaft 12
Is driven in one direction by the ribbon feeding motor 23 and the ribbon winding motor 24 so that the ink ribbon 7 in the printing unit 6 moves in the same direction as the recording material conveying direction. Since the ribbon holding shaft 11 and the ribbon take-up shaft 12 are arranged above the thermal head 5, the ink ribbon 7 can be pressed against the thermal head 5 on the surface opposite to the ink layer to hold the ribbon. It is stretched between the shaft 11 and the ribbon winding shaft 12.

Printing unit 6 in the recording material conveying direction of recording material path 2
A detection sensor S whose output changes depending on whether or not a recording material conveyed in the recording material path 2 passes is provided on the upstream side. The detection sensor S of the present embodiment is a transmissive optical sensor whose output changes according to a change in the amount of light received by the light receiving element S1 that receives the light emitted from the light emitting element S2.
In the present embodiment, the position detected by the detection sensor S is the preparation position Pu.

Next, the electrical connection of each part of the thermal transfer printer 1 will be schematically described with reference to FIG. FIG. 2 is a block diagram schematically showing the electrical connection of each part of the thermal transfer printer 1. The thermal transfer printer 1 contains a microcomputer (hereinafter, referred to as a microcomputer) 14, and the microcomputer 14 drives and controls each unit in the thermal transfer printer 1. The microcomputer 14 is a CPU (Cen) that centrally controls the drive of each unit in the thermal transfer printer 1.
ROM (Read Only Memor) in which fixed data such as control programs are stored in advance in the tral processing unit) 15.
y) 16 and variable data can be rewritably stored and stored as C
RAM (Random) that functions as a work area for PU15
Access Memory) 17 is connected via a bus line 18.

The character generator ROM 19 is connected to the CPU 15. The character generator ROM 19 stores and holds character characters indicating characters to be printed in association with each character code.

The ROM 16 stores a head energization table (not shown). The head energization table stores therein information relating to the pulse width to be energized for each heating element of the thermal head 5 in the printing process described later.

The RAM 17 has a counter buffer for counting various times in the printing process described later, and print data 100 received from a host computer (not shown).
Various buffers such as a reception buffer for temporarily storing (see FIG. 3) and an edit buffer for expanding dots of the print data 100 temporarily stored in the reception buffer are secured.

FIG. 3 is a schematic diagram showing the data structure of the print data 100 transmitted from the host computer to the thermal transfer printer 1. The print data 100 is shown in FIG.
As shown in FIG. 1, one-line print data 101 including a character code indicating the print content, a print command 102 for specifying that the one-line print data 101 is the print data 100, and a character attribute code 10 indicating the font of the print data 100 and the like.
3, a print position code 104 that specifies the print position of the one-line print data 101, an end code 105 that indicates the end of the print data 100, and the like.

Print data 10 stored in the reception buffer
0 indicates that the print content indicated by the one-line print data 101 refers to the character generator ROM 19,
In the form of a character character corresponding to the font indicated by the character attribute code 103, dots are expanded in the edit buffer so as to be printed at the print position specified by the print position code 104.

Below, each part whose drive is controlled by the microcomputer 14 will be explained.

The thermal head 5 is driven based on the print data (DATA) from the CPU 15, the clock signal (CLOCK) which is a basic signal of the printing operation, and the strobe signal (STROBE).

A platen motor 9 for rotating the platen 4 is driven by a C
It is connected to the PU 15. The platen motor controller 20 drives and controls the platen motor 9 based on a control signal from the microcomputer 14.

The head solenoid 10 for driving the head holding mechanism is connected to the CP via the solenoid controller 26.
It is connected to U15. The head solenoid 10 is driven to switch ON / OFF based on a control signal from the microcomputer 14.

The ribbon feeding motor 23 and the ribbon winding motor 24 are connected to the CPU 15 via a ribbon motor controller 25. The ribbon motor controller 25 drives and controls the ribbon feeding motor 23 and the ribbon winding motor 24 based on a control signal from the microcomputer 14.

The detection sensor S is connected to the CPU 15 via the sensor I / F 21. The output of the detection sensor S changes according to a change in the amount of light received by the light receiving element S1 due to the recording material crossing the optical axis. Sensor I / F21
Outputs the output change of the detection sensor S to the microcomputer 14. The microcomputer 14 determines whether or not the trailing edge of the recording material has passed at the preparation position Pu based on the output change of the detection sensor S output from the sensor I / F 21 in the printing process described later.

In addition, the CPU 15 is connected with a communication I / F 22 for performing data communication with a host computer (not shown) such as a personal computer. The print data 100 transmitted from the host computer is received via the communication I / F 22.

Next, the printing process executed by the thermal transfer printer 1 will be described with reference to FIGS. 4 and 5. Figure 4
3 is a flowchart schematically illustrating a printing process executed by the thermal transfer printer 1. Further, FIG. 5 is a timing chart showing the relationship between the position of the recording material between the platen 4 and the thermal head 5, the printing range, and the position of the thermal head 5 during the printing process. In the print processing, as shown in FIG. 4, the print command 102 included in the print data 100 transmitted from the host computer.
It waits until it is determined that the message has been received (N in S1).

When it is determined that the print command 102 transmitted from the host computer is received (Y of S1), the platen motor controller 20 drives the platen motor 9 and the ribbon motor controller 25 drives the ribbon feeding motor 23 and The ribbon winding motor 24 is driven (S2). As a result, the recording material is conveyed through the recording material path 2 and the ink ribbon 7 is wound around the ribbon winding shaft 12 in accordance with the conveying speed of the recording material conveyed through the recording material path 2.

Then, the leading edge of the recording material passes through the contact position Pp between the platen 4 and the thermal head 5 (Ps in FIG. 5).
(See Pm), when it is conveyed to the print start position acquired based on the print data 100 (see Pm in FIG. 5), printing is performed based on the print data 100 expanded in the edit buffer.
(S3).

Since this is a known technique, detailed description thereof will be omitted. In step S3, a pulse for energizing the thermal head 5 is referred to by referring to the head energizing table based on the one-line print data 101 which is dot-developed in the edit buffer. The width is acquired and the pulse width corresponding to the heating element corresponding to the print dot in the thermal head 5 is energized. As a result, printing is performed.

End code 1 included in print data 100
Print end position acquired based on 05 (see Pn in Fig. 5)
When printing is performed up to this point, it waits until it is determined that the trailing edge of the recording material has passed the detection sensor S based on the output change of the detection sensor S (N in S4), and When it is determined that the trailing edge of the recording material has passed the detection sensor S (Y in S4), the head solenoid 10 is turned on after waiting a predetermined time, and the ribbon motor controller 25 causes the ribbon delivery motor to move. 23
And driving of the ribbon winding motor 24 is stopped (S
5). Here, the function as the trailing edge arrival determination means is executed by Y in step S4, and the function as the head displacement means is executed by step S5.

Here, the predetermined time waiting for the passage is
This is the time required from when it is determined that the rear end of the recording material has passed the detection sensor S based on the output change of the detection sensor S until the rear end of the recording material reaches the contact position Pp.

When the trailing edge of the recording material passes through the contact position between the platen 4 and the thermal head 5, the head holding mechanism is positioned at the ribbon save position and the ribbon take-up shaft 12 rotates. Be stopped.

As a result, when the trailing edge of the recording material passes through the contact position Pp between the platen 4 and the thermal head 5,
Since the platen 4 and the thermal head 5 are separated from each other,
It is possible to prevent the ink ribbon 7 from being rubbed against the trailing end of the recording material by the thermal head 5 sliding down on the trailing end of the recording material (see Pn in FIG. 5) and the trailing end of the recording material becoming dirty.

When the thermal head 5 is separated from the platen 4 and at the same time the rotation of the ribbon take-up shaft 12 is stopped, the unused ink ribbon 7 is taken up by the ribbon take-up shaft 12. 7
It is possible to prevent wasteful consumption of.

Next, a second embodiment of the present invention will be described with reference to FIGS. 6 to 9. In the thermal transfer printer 1 of the present embodiment, the thermal head 5 is appropriately displaced between the printing position and the ribbon save position according to the type of recording material used. The same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 6 is a schematic view showing the structure of the thermal transfer printer 1 according to the second embodiment of the present invention. The thermal transfer printer 1 according to the present embodiment includes a recording material type designating unit that designates whether the recording material to be printed is an envelope or a single-cut sheet, and a leading end of the recording material conveyed in the recording material path 2. However, the leading edge arrival determining means for determining whether or not the preparation position Pu has been reached, and the leading edge of the recording material transported in the recording material path 2 are in the recording material transport direction from the contact position Pp in the recording material path 2. A leading end passage judging means for judging whether or not the passing position Pd set on the downstream side has been passed, and the head displacing means is such that the recording material type designated by the recording material type designating means is an envelope. If the leading edge arrival determining means determines that the leading edge of the recording material has reached the preparation position Pu, the thermal head 5 is separated from the platen 4, and the leading edge passage determining means determines the leading edge of the recording material to pass the passage position Pd. If it is judged that it has passed, the service The heads or others 5 is brought into contact with the platen 4.

The RAM 17 is referred to at the time of printing processing which will be described later, and after the leading edge of the recording material has passed the detection sensor S, the RAM 17 is moved to the passing position Pd which is set on the downstream side of the contact position Pp in the recording material conveying direction. The leading end arrival time T1 related to the time required to reach the position is stored.

Here, FIG. 7 is a schematic diagram showing the data structure of the print data 110 transmitted from the host computer to the thermal transfer printer. The print data 110 is, as shown in FIG. 7, one-line print data 101, print command 10
2. In addition to the character attribute code 103, the print position code 104, and the end code 105, an envelope flag 11 that specifies whether the recording material to be printed is an envelope or a cut sheet.
It is composed of 1.

The envelope flag 111 is a variable that specifies whether the recording material to be printed is an envelope or a single-cut sheet in the printing process described later, and is "0" or "1".
Represented by In this embodiment, the envelope flag 1
When 11 is set to “0”, the recording material to be printed is a single-cut sheet and the envelope flag 111 is “1”.
When set to, the recording material to be printed is set to the envelope. The designation of the recording material type is performed by the operator using a personal computer (not shown).

Next, the printing process executed by the thermal transfer printer 1 will be described with reference to FIG. FIG. 8 is a flow chart schematically explaining the printing process executed by the thermal transfer printer 1. Further, FIG. 9 is a timing chart showing the relationship between the position of the recording material between the platen 4 and the thermal head 5, the printing range, and the position of the thermal head 5 during the printing process. The thermal transfer printer 1
The process waits until it is determined that the print command 102 included in the print data 110 transmitted from the host computer is received (N in S10).

When it is determined that the print command 102 included in the print data 110 transmitted from the host computer is received (Y in S10), the platen motor controller 20 drives the platen motor 9 and the ribbon motor controller 25. Thus, the ribbon feeding motor 23 and the ribbon winding motor 24 are driven (S11). As a result, the recording material is conveyed through the recording material path 2 and the ink ribbon 7 is wound around the ribbon winding shaft 12 in accordance with the conveying speed of the recording material conveyed through the recording material path 2.

Subsequently, by referring to the print data 110 transmitted from the host computer, it is determined whether the envelope flag 111 is set to "0" or "1", and the print target is printed. It is determined whether the recording material to be the cut sheet is a cut sheet or an envelope (S12). The thermal transfer printer 1 determines the designated recording material type by determining whether the envelope flag 111 is set to “0” or “1”. Here, the function as the recording material type designating means is executed.

When it is determined that the envelope flag 111 is set to "1" (Y in S12), it is determined that the recording material to be printed is an envelope, and a predetermined time elapses. , While turning on the head solenoid 10,
The ribbon motor controller 25 stops driving the ribbon feeding motor 23 and the ribbon winding motor 24 (S13).

As a result, when the leading edge of the recording material passes through the contact position between the platen 4 and the thermal head 5, the head holding mechanism is positioned at the ribbon save position and the rotation of the ribbon take-up shaft 12 is stopped. To be done.

When the leading edge of the recording material passes the contact position Pp, since the platen 4 and the thermal head 5 are separated from each other, the thermal head 5 is pushed up to pass the contact position Pp. It is possible to prevent the ink ribbon 7 from being rubbed by the front end of the recording material (see Pm in FIG. 5) and the front end of the recording material becoming dirty.

Further, when the thermal head 5 is separated from the platen 4 and at the same time the rotation of the ribbon take-up shaft 12 is stopped, the unused ink ribbon 7 is taken up by the ribbon take-up shaft 12 and the ink ribbon is wound. 7
It is possible to prevent wasteful consumption of.

Based on the change in the output of the detection sensor S, the process waits until it is determined that the leading edge of the recording material has been detected (N in S14).

When it is determined that the leading edge of the recording material has been detected based on the output change of the detection sensor S (Y in S14),
The counting of time t1 is started in the counter buffer (S15).

Tip arrival time T1 stored in RAM 17
When it is determined that the time t1 counted in the counter buffer has reached the leading edge arrival time T1 (Y in S16), the head solenoid 10 is turned off and the ribbon motor controller 25 sends the ribbon. The motor 23 and the ribbon take-up motor 24 are driven (S17), and printing is performed based on the print data 110 dot-developed in the edit buffer (S18). Here, the function as the leading edge arrival determination means is executed in step S16.

Here, the leading edge arrival time T1 is the time required for the leading edge of the recording material to reach the passing position Pd after the leading edge of the recording material S passes. Therefore, the designated recording material type is an envelope. If it is determined that the leading edge of the recording material has reached the preparation position, the head holding mechanism is positioned at the ribbon save position and the thermal head 5 is separated from the platen 4. If it is determined that the leading edge of the recording material has passed the passing position, the head holding mechanism is positioned at the printing position and the thermal head 5 is brought into contact with the platen 4.

As a result, the thermal head 5 is brought into contact with the platen 4 after the leading edge of the recording material has passed between the thermal head 5 and the platen 4, so that the thermal head 5 and the platen in contact with each other. As compared with the case where the envelope is conveyed between the 4th and 4th sides, the occurrence of pulling and wrinkling of the envelope due to the difference in the conveying state of the envelope between the platen 4 side and the thermal head 5 side is prevented, and the envelope is prevented from rising. can do. As a result, it is possible to prevent the envelope from becoming dirty due to the envelope being rubbed against the ink ribbon 7.

When it is determined that the trailing edge of the recording material has been detected after printing is completed based on the change in the output of the detection sensor S,
(Y in S19) After waiting a predetermined time, the head solenoid 10 is turned on, and the ribbon motor controller 25 stops driving the ribbon feeding motor 23 and the ribbon winding motor 24 (S20). Here, the function as the head displacing means is executed by steps S13, S17, and S20.

As a result, when the recording material passes through the contact position Pp between the platen 4 and the thermal head 5, the platen 4 and the thermal head 5 are separated from each other. It is possible to prevent the ink ribbon 7 from being rubbed against the trailing end of the recording material and being soiled at the trailing end of the recording material by sliding off the edge (see Pn in FIG. 5).

When the thermal head 5 is separated from the platen 4 and at the same time the rotation of the ribbon take-up shaft 12 is stopped, the unused ink ribbon 7 is taken up by the ribbon take-up shaft 12. 7
It is possible to prevent wasteful consumption of.

When it is determined that the envelope flag 111 is set to "0" (N in S12), it is determined that the recording material to be printed is a cut sheet, and the print data 110 is printed.
Based on the above, normal printing is performed (S21).

Here, the normal printing executed in step S21 means that the head solenoid 10 is turned off immediately before the printing position for the recording material conveyed in the recording material path 2 and the ribbon motor controller is operated. The ribbon feeding motor 23 and the ribbon winding motor 24 are driven by 25, and the head solenoid 10 is turned on when printing is completed, and the ribbon motor controller 25 drives the ribbon feeding motor 23 and the ribbon winding motor 24. Stop.

As a result, when a cut sheet that does not need to press the recording material with the thermal head 5 is used as the recording material because it does not swell, other than printing,
Since the thermal head 5 and the platen 4 can be separated from each other and the rotation of the ribbon winding shaft 12 can be stopped, the unused ink ribbon 7 is wound around the ribbon winding shaft 12 and the ink ribbon 7 is wasted. It can prevent consumption.

Next, a third embodiment of the present invention will be described with reference to FIGS. The thermal transfer printer 1 according to the present embodiment is configured such that a transport length designating unit that designates the length of the recording material in the transport direction and a preparation position Pu according to the length of the recording material in the transport direction designated by the transport length designating unit. The preparation position setting means for setting the distance from the contact position Pp of the head, the head displacing means determines that the rear end of the recording material has passed the preparation position Pu set by the preparation position setting means. The thermal head 5 is separated from the platen 4.

RAM of the thermal transfer printer 1 of this embodiment
A recording material type file 50 (see FIG. 10) referred to in the printing process described later is stored in the storage unit 17. The recording material type file 50 includes a recording material type code 51 set for each type of envelope designated as a recording material to be printed.
The size 52 of each recording material, the leading edge arrival time T1, the trailing edge arrival time T2, and the like are stored in association with each other.

The recording material type code 51 of the present embodiment is set for each type of envelope and is represented by an n-digit number. For example, the recording material type codes for single-cut sheets such as business cards and postcards are all n digits "0" such as 0000.
It is represented by a list.

In this embodiment, the size 52 of each recording material is
Is represented by (length in the main scanning direction) × (length in the sub-scanning direction), and in the printing process described later, the longer dimension is obtained as the length in the conveying direction of the recording material. .

The leading edge arrival time T1 is information relating to the time required to convey the recording material from when the leading edge of the recording material passes the detection sensor S to when it passes the passing position Pd.
The trailing edge arrival time T2 is information related to the time required from the leading edge of the recording material passing through the detection sensor S to the trailing edge of the recording material reaching the preparation position Pu. That is, in the present embodiment, by setting the trailing edge arrival time T2, the preparation position Pu is set based on the timing when the leading edge of the recording material passes the detection sensor S.

Here, FIG. 11 is a schematic diagram showing the data structure of the print data 120 transmitted from the host computer to the thermal transfer printer 1. As shown in FIG. 11, the print data 120 includes one-line print data 101, a print command 102, a character attribute code 103, and a print position code 10.
4, the recording material type code 51 in addition to the end code 105. The designation of the recording material type code 51 in the print data 120 is performed by an operator using a personal computer (not shown).

Next, the printing process executed by the thermal transfer printer 1 will be described with reference to FIG. FIG. 12 is a flowchart schematically illustrating the printing process executed by the thermal transfer printer 1.

The thermal transfer printer 1 waits until it determines that the print command 102 included in the print data 120 transmitted from the host computer is received (S3).
(N of 0), when it is determined that the print command 102 included in the print data 120 transmitted from the host computer is received (Y of S30), the platen motor controller 20 drives the platen motor 9 and
The ribbon motor controller 25 drives the ribbon feeding motor 23 and the ribbon winding motor 24.
(S31). As a result, the recording material is conveyed through the recording material path 2 and the ink ribbon 7 is wound around the ribbon winding shaft 12 in accordance with the conveying speed of the recording material conveyed through the recording material path 2.

With reference to the recording material type file 50, the recording material type code 51 corresponding to the recording material type code 51 included in the print data 120 is searched (S32).

By determining the presence / absence of the recording material type code 51 corresponding to the recording material type code 51 included in the print data 120, the size 52 of the designated recording material type can be determined. Here, in the present embodiment, the size 52 of each recording material is represented by (length in the main scanning direction) × (length in the sub-scanning direction). , Is obtained by specifying the recording material type. Here, the function as the transport length designating means is executed.

When it is determined that the corresponding recording material type code 51 exists in the recording material type file 50 (Y in S33), the head solenoid 10 is turned on after waiting a predetermined time, and the ribbon motor is turned on. The controller 25 stops driving the ribbon feeding motor 23 and the ribbon winding motor 24 (S34).

As a result, when the leading edge of the recording material passes through the contact position between the platen 4 and the thermal head 5, the head holding mechanism is positioned at the ribbon save position and the rotation of the ribbon winding shaft 12 is stopped. To be done.

When the leading edge of the recording material passes through the contact position Pp, the platen 4 and the thermal head 5 are separated from each other. Therefore, the thermal head 5 is pushed up to pass the contact position Pp. It is possible to prevent the ink ribbon 7 from being rubbed by the front end of the recording material (see Pm in FIG. 5) and the front end of the recording material becoming dirty.

When the thermal head 5 is separated from the platen 4 and at the same time the rotation of the ribbon take-up shaft 12 is stopped, the unused ink ribbon 7 is taken up by the ribbon take-up shaft 12 and the ink ribbon 7
It is possible to prevent wasteful consumption of.

Further, the leading edge arrival time T1 and the trailing edge arrival time T2 corresponding to the corresponding recording material type code 51 are set.
(S35), based on the output change of the detection sensor S, the process waits until it is determined that the leading edge of the recording material is detected (N of S36).

By the way, the trailing edge arrival time T2 set in step S35 is information relating to the time required for the trailing edge of the recording material to reach the preparation position Pu after the leading edge of the recording material passes the detection sensor S. Therefore, the rear end arrival time T2
Is set, the preparation position Pu is set. Here, the function as the preparation position setting means is executed in step S35.

Since the trailing edge arrival time T2 is set based on the timing when the leading edge of the recording material passes the detection sensor S, the preparation position Pu set in step S34.
Is set based on the timing when the leading edge of the recording material passes the detection sensor S.

When it is determined that the leading edge of the recording material has been detected based on the output change of the detection sensor S (Y of S36),
Counting of times t1 and t2 is started in the counter buffer (S37).

By referring to the tip arrival time T1 set in the counter buffer, the process waits until it is judged that the time t1 has reached the tip arrival time T1 (N in S38), and when the time t1 reaches the tip arrival time T1. When it is determined (Y in S38), the head solenoid 10 is turned off, and the ribbon motor controller 25 drives the ribbon feeding motor 23 and the ribbon winding motor 24.
(S39), print data 1 with dots expanded in the edit buffer
Printing is performed based on 10 (S40). Here, the function as the leading edge arrival determination means is executed in step S16.

Here, since the leading edge arrival time T1 is set to the time required to convey the recording material from when the leading edge of the recording material passes the detection sensor S to when it passes the passing position Pd, the thermal head is set. 5 is in contact with the envelope at a position where the front end of the envelope has passed the passing position Pd.

Based on the output change of the detection sensor S, referring to the trailing end arrival time T2 set in the counter buffer,
The process waits until it is determined that the time t2 has reached the rear end arrival time T2 (N in S41), and based on the output change of the detection sensor S, refers to the rear end arrival time T2 set in the counter buffer and refers to the time t2. When it is determined that has reached the trailing edge arrival time T2 (Y in S41), wait for a predetermined time,
The head solenoid 10 is turned on, and the ribbon motor controller 25 stops driving the ribbon feeding motor 23 and the ribbon winding motor 24.
(S42).

Since the trailing edge arrival time T2 is set based on the timing when the leading edge of the recording material passes the detection sensor S, the head solenoid 10 has the trailing edge arrival time T2.
It is turned on depending on whether or not 2 has passed. As a result, even if the detection sensor S cannot detect the trailing edge due to the shape of the envelope, for example, the head solenoid 1 is operated when the trailing edge of the recording material reaches the contact position Pp.
0 can be turned on.

Thus, the position at which the thermal head 5 is separated from the platen 4 can be adjusted according to the size of the recording material in the conveying direction without being influenced by the shape of the envelope, and the thermal head can control the recording material. It is possible to more reliably prevent the rear end of the recording material from being soiled by rubbing the ink ribbon against the rear end of the recording material by sliding down the rear end.

As a result, when the envelope is used as the recording material, the thermal head 5 is moved away from the platen 4 in order to save the ink ribbon. It is possible to prevent the envelope from being soiled by being rubbed by.

When it is determined that the recording material type code 51 corresponding to the recording material type code 51 included in the print data 120 does not exist by referring to the recording material type file 50 (N of S33), Based on the standard printing (S
43).

Here, when it is determined that the trailing edge of the recording material has passed the preparation position Pu, the thermal head 5 is separated from the platen 4.

As a result, when the trailing edge of the recording material passes through the contact position Pp between the thermal head 5 and the platen 4,
Since the thermal head is separated from the platen, it is possible to prevent the ink ribbon from being rubbed against the trailing edge of the recording material due to the thermal head sliding down the trailing edge of the recording material and the trailing edge of the recording material becoming dirty. it can.

[0094]

According to the present invention, it is possible to prevent the rear end of the recording material from being soiled by the thermal head sliding down the rear end of the recording material and rubbing the ink ribbon against the rear end of the recording material. it can.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the structure of a thermal transfer printer according to a first embodiment of the present invention.

FIG. 2 is a block diagram schematically showing the electrical connection of each part of the thermal transfer printer.

FIG. 3 is a schematic diagram showing a data structure of print data transmitted from a host computer to a thermal transfer printer.

FIG. 4 is a flowchart schematically illustrating a printing process executed by a thermal transfer printer.

FIG. 5 is a timing chart showing the relationship between the position of the recording material between the platen and the thermal head, the printing range, and the position of the thermal head during the printing process.

FIG. 6 is a schematic view showing the structure of a thermal transfer printer according to a second embodiment of the present invention.

FIG. 7 is a schematic diagram showing a data structure of print data transmitted from a host computer to a thermal transfer printer.

FIG. 8 is a flowchart schematically illustrating a printing process executed by a thermal transfer printer.

FIG. 9 is a timing chart showing the relationship between the position of the recording material between the platen and the thermal head, the printing range, and the position of the thermal head during the printing process.

FIG. 10 is an image diagram showing a data structure of a recording material type file included in the thermal transfer printer according to the third embodiment of the present invention.

FIG. 11 is a schematic diagram showing a data structure of print data transmitted from a host computer to a thermal transfer printer.

FIG. 12 is a flowchart schematically illustrating print processing executed by a thermal transfer printer.

FIG. 13 is a timing chart showing the relationship between the position of the recording material between the platen and the thermal head, the printing range, and the position of the thermal head during the printing process in the conventional thermal transfer printer.

FIG. 14 is a schematic diagram showing a recording material conveyance state in a conventional thermal transfer printer.

[Explanation of symbols]

1 ... Thermal transfer printer, 2 ... Recording material path, 3 ... Conveying mechanism,
4 ... Platen, 5 ... Thermal head, 6 ... Printing part, 8 ...
Ribbon holding mechanism

Claims (3)

[Claims] 1. A printing method comprising: a recording material path through which a recording material is guided; a transport mechanism for transporting the recording material in the recording material path; and a platen and a thermal head that are arranged to face each other via the recording material path. A head holding mechanism that holds the thermal head so that the thermal head can be moved toward and away from the platen; a ribbon holding mechanism that holds an ink ribbon positioned between the platen and the thermal head in a windable manner; The trailing edge of the recording material conveyed in the recording material path reaches a preparatory position set on the upstream side in the recording material conveying direction from the contact position where the thermal head and the platen in the recording material path contact each other. A trailing edge arrival determining means for determining whether or not the trailing edge arrival determining means determines that the trailing edge of the recording material has reached the preparation position during printing by the printing unit. A head displacement mechanism that separates the thermal head from the platen by the head holding mechanism. 2. A recording material type designating means for designating whether the recording material to be printed is an envelope or a cut sheet, and a leading end of the recording material conveyed in the recording material path is the preparation position. And a leading edge of the recording material conveyed in the recording material path is set downstream of the contact position in the recording material path in the recording material conveying direction. A leading edge passage judging means for judging whether or not the recording material type has passed through the passing position, the head displacing means is provided on condition that the recording material type designated by the recording material type designating means is an envelope. ,
When the leading edge arrival determination means determines that the leading edge of the recording material has reached the preparation position, the thermal head is separated from the platen, and the leading edge passage determination means determines that the leading edge of the recording material has passed the passage position. The thermal transfer printer according to claim 1, wherein when the determination is made, the thermal head is brought into contact with the platen. 3. A conveyance length designating means for designating a length of the recording material in the transport direction, and the contact at the preparation position according to the length of the recording material in the transport direction designated by the transport length designating means. A head position displacing means for setting a distance from a position, wherein the head displacing means has the thermal function when the trailing edge of the recording material is determined to have passed the prep position set by the prep position setting means. The thermal transfer printer according to claim 1, wherein the head is separated from the platen.