JPH04173254A - Thermosensitive recorder - Google Patents

Abstract

PURPOSE:To correct recording state and perform high grade recording regardless of temperature of a recording paper, environmental temperature, type of an ink sheet by detecting the temperature of the recording paper, the environmental temperature, and type of the ink sheet, and controlling temperature of the top surface of a transfer drum. CONSTITUTION:Environmental temperature is detected by a thermistor 102 and temperature of a recording paper 7 is detected by a thermistor 101. An ink cassette 32 is provided with a detecting opening 33 for discriminating type of an ink sheet 3 and an ink sensor 34 discriminates the type of the ink sheet 3 referring to the detecting opening 33. As an adjusting means of temperature of an ink image 31 and of a recording energy at transferring, a means for controlling temperature of the top surface of a silicone rubber layer 12 is used so as to correct a recording state. That is, the temperature of the top surface of the silicone rubber layer 12 is adjusted such that a hot insulation temperature of the top surface of the layer 12 is decided and a power to be supplied to a heater 4 is controlled so as to make the temperature of the surface of the layer 12 equal to the hot insulation temperature by referring to a thermistor 5.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a thermal recording device that records desired images or characters on recording paper in response to electrical signals applied to a thermal recording head.

Conventional technology i4. Thermal recording devices cannot produce clear records without using special recording paper for both digital copiers, facsimile machines, etc.
A heat-sensitive recording apparatus has been devised that can perform clear recording even on plain paper. An example of the above-mentioned conventional heat-sensitive recording apparatus will be described below with reference to the drawings.

FIG. 2 shows a configuration diagram of a conventional thermosensitive recording device. In FIG. 2, 1 is a transfer drum, on the surface of which a transfer layer 12 made of a flexible material is formed. A thermal head 2 faces the transfer drum 1 with an ink sheet 3 in between. The thermal head 2 and the ink sheet 3 are normally spaced apart from the transfer drum 1, but are brought into pressure contact with the transfer drum 1 during strength recording.

4 is a heater, which is energized and controlled by a thermistor 5 provided in contact with the surface of the transfer layer 12 and a temperature control circuit 6.
The surface of the transfer layer 12 is heated and kept at a predetermined temperature.
A recording paper 7 is conveyed between a pressure roller 8 and a transfer drum 1. A cleaning device 9 is provided in contact with the transfer layer 12. The operation of the thermal recording apparatus configured as above will be described below.

First, when a recording command is input, the thermal head 2 is brought into pressure contact with the transfer drum 1 via the ink sheet 3. The thermal head 2 melts the ink applied on the ink sheet 3 according to the recording signal and forms an ink image 31 on the surface of the transfer layer 12.
form. The ink image 31 moves in the direction of the arrow and is transferred onto the recording paper 7 between the pressure roller 8 and the transfer drum 1.

At this time, since the transfer layer 12 formed on the surface of the transfer drum 1 has flexibility, the ink image 31 closely follows the surface of the recording paper 7 and is faithfully transferred, so that clear recording can be performed. can. Then, the ink image 31 remaining on the surface of the transfer layer 12 without being transferred to the recording paper 7 is removed from the transfer layer 12 by the cleaning device 9 (for example, Shibu JP-A-62
-248669).

Problems to be Solved by the Invention However, with the above configuration (1) If the temperature of the recording paper 7 decreases, the ink image 31 may not be sufficiently transferred to the recording paper 7, resulting in transfer failure, or if the type of ink sheet 3 is different. Since the energy required for recording is different, there is a problem that the print quality is deteriorated such as the print density fluctuates.9 The present invention takes into account the above problems.It is an object of the present invention to perform high-quality recording without transfer defects or print density fluctuations. The purpose of the present invention is to provide a thermal recording device that can perform the following functions.

Means for Solving the Problems In order to solve the above problems, the thermal recording apparatus of the present invention is provided with a configuration in which the temperature of the surface of the transfer drum is controlled according to the temperature of the recording paper and the type of the ink sheet.

Function The present invention can correct the recording state by referring to the temperature of the recording paper and the type of ink sheet with the above-described configuration, so that high-quality recording can be performed without transfer defects or print density fluctuations.

EXAMPLE Hereinafter, a thermal recording apparatus according to an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a block diagram of a thermal recording apparatus in an embodiment of the present invention. In FIG.
was formed. A thermal head 2 has a large number of heating element rows 21 arranged in the width direction of the transfer drum 1, and faces the transfer drum 1 with an ink sheet 3 in between. Note that the thermal head 2 and the ink sheet 3 are normally separated from the transfer drum 1 by force (when recording, they are brought into pressure contact with the transfer drum 1). A detection port 33 for determining the type of ink sheet 3 stored in the cassette 32 is provided.

An ink sheet 34 is provided facing the detection port 33 . Reference numeral 4 denotes a heater, which is energized and controlled by a temperature control circuit 6 to heat and keep the surface of the silicone rubber layer 12 warm. A thermistor 5 is provided in contact with the surface of the silicone rubber layer 12.

A recording paper 7 is conveyed between a pressure roller 8 and a transfer drum 1. A cleaner 9 is provided in contact with the silicone rubber layer 12. A thermistor 101 is provided so as to be in contact with the recording paper 7. A thermistor 102 is provided inside the device to detect the environmental temperature inside the device.

The operation of the thermal recording apparatus configured as described above will be explained below with reference to FIG. First, the recording operation will be explained.

When a recording command is input, the thermal head 2 is brought into pressure contact with the transfer drum 1 via the ink sheet 3. The thermal head 2 melts the ink applied on the ink sheet 3 by energizing the heating element 21 according to the recording signal.
An ink image 31 is formed on the surface of the silicone rubber layer 12. When the formation of the ink image 31 is completed, the thermal head 2 is separated from the transfer drum l. The ink image 31 is moved in the direction of the arrow and transferred onto the recording paper 7 between the pressure roller 8 and the transfer drum 1. At this time, since the silicone rubber layer 12 formed on the surface of the transfer drum 1 has flexibility, the ink image 31 closely follows the surface of the recording paper 7 and is faithfully transferred, so that clear recording can be performed. I can do it. Further, the ink image 31 remaining on the surface of the silicone rubber layer 12 without being transferred to the recording paper 7 (is removed from the silicone rubber layer 12 by the main cleaner 9).

Next, a method for controlling the temperature of the surface of the silicone rubber layer 12 will be explained.

In this thermal recording device, the surface of the silicone rubber layer 12 is constantly heated and kept at about 60 to 70°C, and the temperature inside the device gradually rises until it is saturated at a certain temperature. The temperature of ink sheet 3]
The print density fluctuates when the plate increases by 1. Therefore, it is necessary to suppress print density fluctuations by adjusting the recording energy.

Therefore, the temperature inside the device (hereinafter referred to as environmental temperature) is detected by the thermistor 102.

Also, the recording paper 7 is energized.The temperature of the recording paper 7 does not match the environmental temperature. The ink image 31 on the surface of the layer 12 is not sufficiently transferred to the recording paper 7, resulting in a transfer failure. Therefore, it is necessary to adjust the temperature of the ink image 31 during transfer. Therefore, the temperature of the recording paper 7 is detected by the thermistor 101.

In addition, the ink sheet 3 includes a single color ink sheet that usually consists of only black ink, a color ink sheet that consists of three colors of yellow, magenta, and cyan, or four colors of ink with black added, and a multi-time ink that can be used many times. There are different types of ink sheets, etc., and when using each ink sheet, it is necessary to adjust the recording energy according to the ink sheet used. A detection port 33 for determination is provided, and an ink sensor 34 refers to the detection port 33 to detect the ink sheet 3.
Determine the type of.

The ink image 31 during transfer with respect to the above changes in recording conditions.
The recording state is corrected using a means for controlling the temperature of the surface of the silicone rubber layer 12 as means for adjusting the temperature and recording energy. Specifically (friend temperature control circuit 6
By referring to the outputs of the thermistors 101 and 102 and the ink sensor 34, for example, referring to a temperature table prepared in advance, the heat retention temperature of the surface of the silicone rubber layer 12 is determined to correct the recording state. The temperature of the surface of the silicone rubber layer 12 is adjusted by referring to the temperature of the surface of the silicone rubber layer 12 using the thermistor 5 and controlling the power supply to the heater 4 so that it is equal to the previously determined heat retention temperature.

As described above, according to this embodiment, the recording state is corrected by providing means for detecting the temperature of the recording paper 7, the environmental temperature, and the type of the ink sheet 3 and controlling the temperature of the surface of the silicone rubber layer 12, thereby correcting the transfer failure. It is possible to perform high-quality recording without density fluctuations.

In the embodiment, as a means for determining the type of ink sheet 3, a detection port 33 is provided in the ink cassette 32 (a reflective tape is provided on the ink cassette 32, a detection mark is placed on the ink sheet 3 itself, a detection mark is placed on the ink sheet 3 itself, or an ink A changeover switch may be provided and the type of ink sheet 3 may be determined by manually switching the switch.

Further, as means for forming an ink image 31 on the surface of the silicone rubber layer 12, a thermal head 2 and an ink sheet 3 are used.
(A current-carrying recording head and a current-carrying recording sheet may be used.)

In addition, after the ink image 31 is transferred to the recording paper 7, the cleaning device 9 is used as a means for removing the ink image 31 remaining on the silicone rubber layer 12 (a means for removing the ink image 31 by re-adhering it to the ink sheet 3). Effects of the Invention As described above, the present invention corrects the recording state by providing means for detecting the temperature of the recording paper, the environmental temperature, and the type of ink sheet, and controlling the temperature of the surface of the transfer drum. Regardless of the temperature of the recording paper, the environmental temperature, or the type of ink sheet, high-quality recording can be performed without transfer defects or density fluctuations.

[Brief explanation of drawings]

FIG. 1 shows the configuration of a thermal recording device according to an embodiment of the present invention. FIG. 2 shows the configuration of a conventional thermal recording device. 1... Transfer drum 2... Thermal head 3...
・Ink sheet, 32... Ink cassette, 33
...Detection n 34...Ink sensor, 4...Heater, 6...Temperature control circuit, 7...Recording paper 8...Pressure roller, 5, 1.01.102...
・Thermista. Name of agent: Patent attorney Akira Okaji and 2 others

Claims (2)

[Claims] (1) An intermediate transfer medium, a heater that heats the intermediate transfer medium, a thermal recording head that is pressed against the intermediate transfer medium through an ink sheet, and a pressure contact that is pressed against the intermediate transfer medium through a recording sheet. a roller, a temperature detecting means A for detecting the temperature of the recording paper, a temperature detecting means B for detecting the temperature of the surface of the intermediate transfer medium, and an output of the temperature detecting means A to determine the keeping temperature of the surface of the intermediate transfer medium. 1. A thermosensitive recording apparatus comprising: a temperature control means for determining the temperature and controlling the heater so that the temperature detected by the temperature detection means B becomes equal to the heat retention temperature. (2) An intermediate transfer medium, a heater that heats the intermediate transfer medium, a thermal recording head that is pressed against the intermediate transfer medium through an ink sheet, and a pressure contact that is pressed against the intermediate transfer medium through a recording sheet. a roller, a type detecting means for detecting the type of the ink sheet, a temperature detecting means for detecting the temperature of the surface of the intermediate transfer medium, and determining a heat retention temperature of the surface of the intermediate transfer medium based on the output of the type detecting means; A thermosensitive recording device comprising: temperature control means for controlling the heater so that the temperature detected by the temperature detection means is equal to the heat retention temperature.