JP3289927B2 - Printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer for heating a recording medium prior to recording.

[0002]

2. Description of the Related Art Conventionally, in this type of printer, as shown in Japanese Utility Model Publication No. 49-42749,
There is an apparatus in which a platen or the like is heated and a recording medium is brought into contact with the platen to heat the recording medium prior to a recording operation. Further, a thermal transfer printer for recording on a recording medium using a heat-meltable ink and a hot-melt inkjet printer are disclosed in
As disclosed in Japanese Patent No. 28878, there is a method in which a recording medium is heated so that a heat-fusible ink penetrates into the fibers of the recording medium to improve the fixing property of the ink. Further, even when a water-soluble ink is used, there is a method in which the ink on the recording medium is dried more quickly by heating the recording medium, the ink is prevented from bleeding on the recording medium, and the recording quality is improved. .

However, not only the temperature at which the recording medium is heated, that is, the appropriate value of the amount of heat applied to the recording medium, differs depending on the thickness of the recording medium. When a transparent film (hereinafter referred to as an OHP film) is used as a recording medium, the appropriate value of the amount of heat applied to the recording medium is significantly different from that when plain paper is used as the recording medium. In ink-jet printers using water-soluble inks, when recording on OHP film, unlike when recording on plain paper, the ink does not penetrate into the fibers of the paper and the ink is very difficult to dry. You need to add a lot of heat to help.
On the other hand, when recording on plain paper, if too much heat is applied, the paper curls or the paper dries rapidly, causing wrinkles. .

In a hot-melt ink-jet printer using a hot-melt ink, when an OHP film is heated and recorded with a calorific value capable of obtaining good recording results on plain paper, the dots of the ink are projected on the OHP film in a convex lens shape. When the recording result is actually viewed through an overhead projector, a clear color is hardly produced because the convex lens-shaped ink refracts light. On the other hand, if too much heat is applied when recording on plain paper, the ink may penetrate too much into the fibers of the paper and the recording result may appear on the back side of the paper. In order to solve these problems, a method has been adopted in which after recording on an OHP film, the OHP film is heated again to melt and flatten the ink raised in a convex lens shape.

[0005]

However, in order to reheat after recording on the OHP film in the recording apparatus, a reheating apparatus for the OHP film must be provided separately. Further, in order to perform the reheating process in the recording apparatus, after recording, it is necessary to provide a separate path depending on the recording medium, a means for switching the path, and a heating means for reheating the path on the OHP film side. . For this reason, in any case, another device is required or the whole device becomes large, so that not only is space saving difficult, but also,
There was a problem that it was difficult to keep costs low. The present invention has been made to solve the above-described problems, and a high-quality recording result can be obtained by heating a recording medium to a temperature according to a type during a recording operation in a recording apparatus. Another object of the present invention is to provide a printer which can save space and cost.

[0006]

According to the present invention, there is provided a printer having a function for heating a recording medium, comprising: a recording unit for recording on the recording medium;
Heating and a platen for supporting the recording medium, heating means for heating the platen to heat the recording medium prior to recording on the recording medium, by heating means
Depending on the type of the recording medium.
Control means for maintaining a constant temperature, and
Therefore, the platen and the recording medium maintained at a constant temperature
Contact between the, in which example Bei a contact state change means for changing in accordance with the type of the recording medium.

[0007]

According to the above arrangement, the platen supporting the recording medium is heated by the heating means so as to be kept at a constant temperature by the control means. Here, for example, when recording is performed on a recording medium requiring a large amount of heat, a large amount of heat is applied to the recording medium by, for example, moving the platen in a direction approaching the recording medium. When recording is performed on a recording medium that does not require a large amount of heat, a small amount of heat is applied to the recording medium by, for example, moving the platen in a direction away from the recording medium by the contact state changing unit. In this way, by changing the contact state between the platen and the recording medium according to the type of the recording medium ,
Therefore , an appropriate amount of heat is given to the recording medium while the temperature of the platen is kept constant.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. 1 and 2 are a top view and a cross-sectional view, respectively, schematically illustrating the ink jet printer of the present embodiment. The ink jet head 20 performs recording by ejecting ink onto a recording medium 22, and a carriage 24 equipped with the ink jet head 20 is driven by a carriage motor 28 to drive guide shafts 26a and 26b (FIG. 1).
The guide shaft 26a is omitted in the figure) so as to be able to move in parallel via the timing belt 30 along the guide shaft 26a. The upstream paper feed roller 32, the downstream paper feed roller 34, the upstream pitch roller 36, and the downstream pitch roller 38 further move the recording medium 22 fed by a paper feeding device such as an unillustrated auto cut sheet feeder to a recording position, that is, an inkjet head 20 onto the platen 40 at the opposing position,
When recording is performed by the inkjet head 20 on the platen 40, the recording paper is sent in the direction of an unillustrated outlet (arrow direction). These rollers 32, 34, 36, 38 are provided with rotating shafts 42a,
It is rotatably supported by the frame 46 via 42b, 44a, 44b. The rotating shafts 42a and 44a are connected to a paper feed motor 50 via a transmission mechanism including a belt 48 and the like.
It is configured to rotate by the drive of.

In order to heat the recording medium 22, a heater 52 for heating the platen 40 is attached to the platen 40 supporting the recording medium 22 at the recording position. The heater 52 in the present embodiment uses a positive temperature characteristic thermistor heater whose resistance value increases as the temperature rises. Since the self-temperature control is possible, control such as applying feedback using a temperature sensor such as a thermistor is performed. The platen 40 can be maintained at a constant set temperature without need. In addition, the melting point of the ink is previously set to Ti
Then, the temperature Tp of the platen 40 is set so that Tp ≧ Ti. It should be noted that control can be similarly performed by applying feedback using a temperature sensor such as a thermistor. Further, an optical sensor 54 for identifying whether the recording medium 22 is a plain paper or an OHP film is disposed at a position before the paper feed roller 32 in the paper feed direction. In this sensor 54, a light emitting diode and a phototransistor face each other, and the recording medium 22 passes between them. Further, a paper end sensor 56 for detecting the leading end of the recording medium 22 is disposed at a position in the paper feeding direction of the optical sensor 54 near a downstream feed roller (not shown).

On the carriage 24 on which the inkjet head 20 is mounted, a light emitting diode and a phototransistor, which are timing pulse generating elements for controlling the driving of the carriage 24 and the ink ejection timing of the inkjet head 20, are arranged to face each other. Read head 5
8 are provided. An optical slit 60 for detecting a recording position is provided between the light emitting diode of the read head 58 and the phototransistor.

The platen 40 in the printer of the present embodiment
3 is a cross-sectional view of the vicinity of the platen 40. FIGS. 4 and 5 are views of the mounting structure of the platen 40 in the printer of the present embodiment viewed from the bottom.
FIG. An arm 62, which is a transmission mechanism for transmitting power required for vertical movement for changing the state of contact with the recording medium 22, is fixed to the platen 40. The platen 40 has concave portions at both ends, is mounted on a convex portion 46a of the frame 46, and moves up and down along the convex portion 46a.

Further, a lever 64 for vertically moving the platen 40 is rotatably attached to the frame 46B by a pin 66. An arm 62 mounted on the platen 40 is attached to one end of the lever 64 so as to be movable along a long hole of the lever 64, and is fixed to a frame 46B at the opposite end by a bolt 67 or the like. The plunger 68a of the solenoid 68 is mounted. When the solenoid 68 is not excited, the platen 40 is moved by its own weight in the opposite direction of the frame 46A, that is, the recording medium 2.
2, and stops at a position where the end of the lever 64 to which the plunger 68a is attached hits the frame 46A. When the solenoid 68 is excited, the plunger 68a is attracted to the solenoid 68, and the plunger 68a moves in the direction of the frame 46B.
It moves in a direction approaching the recording medium 22 on 6A, and stops when it moves to a predetermined position.

Next, a block configuration of a control unit according to this embodiment will be described with reference to FIG. The CPU 70 has a memory 7
2, an optical sensor 54, a paper edge sensor 56, and a reading head 58 are connected, and the inkjet head 20 and the carriage motor 2
8, connected to the paper feed motor 50 and the solenoid 68. The CPU 70 controls the optical sensor 54 and the sheet edge sensor 5 according to an operation program stored in the memory 72 in advance.
6. By reading the signal sent from the read head 58 and controlling the drive circuit 74, the inkjet head 20, the carriage motor 28, the paper feed motor 5
0 and the solenoid 68 are driven. The optical sensor 54 is
The recording medium 22 identifies whether the recording medium 22 is an OHP film or plain paper. The paper end sensor 56 identifies whether the recording medium 22 is at a predetermined position or not. The scanning amount and speed of the carriage 24 are detected to control the driving.

Next, the operation of this embodiment will be described with reference to the flowchart of FIG. First, when a recording start signal is sent from a host device or the like, the inkjet printer uses a paper feeding unit such as an auto cut sheet feeder (not shown) to
The recording medium 22 is fed to a position just before the platen 40 (S1). Next, it is determined by the sheet edge sensor 56 whether the recording medium 22 has been fed to a predetermined position just before the platen 40 (S2). If the recording medium 22 has not been fed to the predetermined position, the host device and the operator are notified that a paper jam has occurred, and the operation is stopped (S3). When the recording medium 22 has been fed to a predetermined position, the optical sensor
Whether the recording medium is a P film or plain paper
(S4).
When the recording medium 22 is identified as plain paper, the CPU
70 controls the drive circuit 74 to drive the paper feed motor 50, so that the upstream paper feed roller 32 and the downstream paper feed roller 34
Is rotated to feed the recording medium 22 to a predetermined recording position (S5), and the inkjet head 20, the carriage motor 28, and the paper feed motor 50 are driven to execute a recording operation (S6). When the recording operation of one recording medium 22 is completed, the recording medium 22 is sent to a discharge port (not shown), and the operation is terminated (S11).

When the recording medium 22 is identified as an OHP film (NO in S4), the CPU 70 drives the drive circuit 74.
To excite the solenoid 68 to move the platen 40 in the direction of the recording medium sent to the recording position, that is, upward (S7). Thereby, the recording medium 2
2 compared to using plain paper for heated platen 40
Is closer to the recording medium 22, and more heat can be applied to the OHP film. The paper feed motor 50 is driven to rotate the upstream paper feed roller 32 and the downstream paper feed roller 34 to feed the recording medium 22 to a predetermined recording position (S8), and execute the recording operation in the same manner as described above (S9). When the recording operation of one recording medium 22 is completed, the excitation of the solenoid 68 is turned off (S10).
As a result, the platen 40 moves in the direction opposite to the recording position, that is, downward. Then, the recording medium 22 is sent toward the discharge port (not shown), and the operation is terminated (S11).

Next, a second embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. FIGS. 8 and 9 are cross-sectional views around the platen 40 of the second embodiment. The schematic configuration is the same as that of the first embodiment, but the configuration of the platen 40 and its surroundings is different. This embodiment is basically the same as the first embodiment shown in FIG. 6, but in the first embodiment, the platen 40 is moved up and down using the solenoid 68 and is added to the recording medium 22. In the second embodiment, the platen 40 is rotated and the recording medium 22 is rotated by using the step motor 86.
The amount of heat applied to the device is adjusted.

In this embodiment, the platen 40 is rotatably attached to the frame 46 by a platen rotation shaft 76. The platen 40 is made of aluminum material, has a triangular prism approximate shape in which a rectangular side surface appears on the printing position side, and a resin plate 78 is attached to one side surface thereof. The second side surface is in a state where the aluminum material has appeared, and the fan-shaped gear 80 is mounted on the third side surface. The platen 40 includes the gear 80,
The motor is rotated by a step motor 86 via a transmission mechanism constituted by an idle gear 82 and a motor gear 84. Further, the teeth at both ends of the gear 80 are not cut so that the platen 40 does not rotate beyond a certain angle, and the rotation is stopped when the gear 80 reaches a predetermined rotation position.

FIG. 8 shows a step motor 86 with a clock (CW).
In this state, the surface of the resin plate 78 affixed to the platen 40 appears at the recording position and comes into contact with the recording medium 22. FIG. 9 shows a state in which the step motor 86 is rotated in the counterclockwise (CCW) direction by a fixed number of steps. In this state, a side surface of the platen 40 made of an aluminum material to which the resin plate is not attached appears, and 22 will be contacted.

The operation of the second embodiment will be described with reference to FIG. First, the power of the printer is turned on, and the printer performs initial settings (S21). Next, the step motor 86 is rotated by a predetermined amount in the CW direction when viewed from the direction in which the motor gear 84 is attached, with the number of steps of rotating the platen 40 by an angle equal to or more than the rotatable angle. By this rotation, the platen 40 stops rotating when the side surface on which the resin is adhered as shown in FIG. 8 is brought into the recording position side (S22). The platen 40 is held at the position where the driving of the step motor 86 is stopped, and thus, in the initial state, the platen 4
The surface of the resin plate 78 attached to the recording medium 22 appears at a position where it comes into contact with the recording medium 22 (S23). When the recording start signal is sent from the host device or the like, the ink jet printer feeds the recording medium 22 to a position just before the platen 40 by a paper feeding device such as an auto cut sheet feeder (not shown) (S24).

Next, the recording medium 2 is detected by the sheet edge sensor 56.
It is determined whether or not 2 has been sent to a predetermined position before the platen 40 (S25). When it is determined that the recording medium 22 has not been sent to the predetermined position, the host device and the operator are notified that a paper jam has occurred,
The operation is stopped (S26). When it is determined that the recording medium 22 has been fed to a predetermined position, the optical sensor 54 determines whether the recording medium 22 is an OHP film or plain paper by transmitting the light of the recording medium 22 to light. It is identified by the difference in the rates (S27). If it is determined that the recording medium 22 is plain paper, the CPU 70
4 to drive the paper feed motor 50 to rotate the upstream paper feed roller 32 and the downstream paper feed roller 34 to feed the recording medium 22 to a predetermined recording position (S28), the inkjet head 20, the carriage motor 28, and the paper feed. The recording operation is executed by driving the motor 50 (S29). 1
When the recording operation of the two recording media 22 is completed, the recording medium 2
2 is sent in the direction of the discharge port (not shown), and the operation ends (S34).

When the recording medium 22 is identified as an OHP film (NO in S27), the CPU 70 controls the drive circuit 74 to rotate the platen 40 to move the aluminum material toward the recording position shown in FIG. The step motor 86 is rotated by N steps in the CCW direction so that a side surface consisting of is formed (S30). As a result, when an OHP film is used for the recording medium 22, the side surface made of an aluminum material appears on the recording position side and comes into contact with the recording medium 22, so that the side on which the resin is adhered is made of aluminum. Since the surface made of a suitable metal has high thermal conductivity, more heat can be applied to the OHP film. Next, the paper feed motor 50 is driven to rotate the upstream paper feed roller 32 and the downstream paper feed roller 34,
The recording medium 22 is sent to a predetermined recording position (S31), and the recording operation is performed in the same manner as described above (S32). When the recording operation of one recording medium 22 is completed, the step motor 86
Is rotated N steps in the CW direction, and the platen 40 returns to the state shown in FIG. 8 in which the side surface to which the resin is attached appears on the recording position side (S33). The recording medium 22 is sent toward the discharge port (not shown), and the operation ends (S34).

The present invention is not limited to the configuration of the above embodiment,
Various modifications are possible. For example, in the second embodiment, a resin plate 78 is adhered to the platen 40, but the shape of the platen 40 is changed as shown in FIG. It can also be realized by changing the shape and changing the area of the platen 40 in contact with the recording medium 22.

[0023]

As is apparent from the above description, according to the present invention, by changing the contact state between the platen and the recording medium in accordance with the type of the recording medium, the temperature of the platen can be kept constant. The amount of heat applied to the recording medium can be easily and quickly adjusted. For this reason, regardless of whether plain paper or OHP film is used as the recording medium, good recording results can be obtained without a decrease in throughput. In particular, in the present invention, it is not necessary to change the heating temperature of the platen according to the type of the recording medium. Therefore, for example, even when the identification unit for detecting the type of the recording medium is provided, the detection result is not changed. By changing the contact state between the platen and the recording medium based on this, the amount of heat applied to the recording medium can be adjusted easily, quickly, and accurately. Therefore, even in a case where plain paper and OHP films are alternately used, a series of recording operations can be quickly and accurately performed without a decrease in throughput.

[Brief description of the drawings]

FIG. 1 is a top view schematically showing a printer according to a first embodiment of the present invention.

FIG. 2 is a sectional view schematically showing a printer according to the first embodiment of the present invention.

FIG. 3 is a sectional view of a portion around a platen of the printer according to the first embodiment of the present invention.

FIG. 4 is a bottom view of a portion around a platen of the printer.

FIG. 5 is a front view of a peripheral portion of a platen of the printer.

FIG. 6 is a block diagram of a control unit of the printer according to the first embodiment of the present invention.

FIG. 7 is a flowchart of an operation according to the first embodiment of the present invention.

FIG. 8 is a side view of a peripheral portion of a platen according to a second embodiment of the present invention.

FIG. 9 is a side view of a platen peripheral portion according to a second embodiment of the present invention.

FIG. 10 is a flowchart of an operation according to the second embodiment of the present invention.

FIG. 11 is a side view of a portion around a platen showing a modification of the second embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 40 platen 52 heater 54 optical sensor 62 arm 64 lever 68 solenoid 76 platen rotation shaft 78 resin plate 80 gear 86 step motor

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41J 11/02

Claims (1)

(57) [Claims] 1. A printer having a functional structure for heating the recording medium, said recording means for effecting recording on a recording medium, a platen for supporting the recording medium, the recording medium prior to recording on the recording medium a heating means for heating the platen to heat the pressurized by the heating means
The temperature of the heated platen depends on the type of the recording medium.
Control means for maintaining a constant temperature regardless of the
The platen and the record kept at a constant temperature by a step
Printer, characterized in that the contact with the medium, and e Bei and <br/> Ru contact state changing means change depending on the type of the recording medium.