JPS60248369A - Heat-sensitive recorder - Google Patents

Abstract

PURPOSE:To provide a heat-sensitive recorder capable of easily grading a dispersion of parasitic resistance value in a heating resistance element of a thermal head and producing stable print. CONSTITUTION:A junction flat cable 2 is connected to a flexible flat cable 4 forming a feeder channel from a drive control power supply PS, and another end of the junction flat cable 2 is connected to a thermal head 1. In the interior of the junction flat cable 2, a sensing energizing channel 21 formed through the detection 8 of a drive control power supply PS and a series resistor 7 in proportion to the number of classified grades of a resistance value of the heating resistance element 11 is provided in addition to a feeder channel 22 to the heating resistance element 11 of the thermal head 1. Then the grades of the heating resistance element 11 are distinguishably indicated by cutting and fabricating the sensing energizing channel 21. At the same time, a power supply is automatically adjusted according to a dispersion of the resistance value of the heating resistance element 11.

Description

DETAILED DESCRIPTION OF THE INVENTION (Objective of the Invention) The present invention provides an improved thermal recording medium that can easily grade variations in resistance values parasitic to heating resistive elements of a thermal head and that can obtain stable printing quality. There is a device.

(Prior art) Print heads used in thermal printers have heating resistor elements patterned on an insulating substrate, but it is inevitable that the individual resistance values will vary, so they are classified into several grades. However, printing is performed while adjusting the applied voltage according to each grade. By the way, the method of classifying the resistance value requires identification processing on the print head, such as by color coding or code number, and is accompanied by troublesome sorting work.On the other hand, even if it is classified by grade, it is difficult to identify the heat generating resistor element. In addition to requiring adjustment means that can maintain a constant amount of heat generated inside the head by controlling the energizing voltage, energizing time, etc., there is also a need for adjustment means that can maintain a constant amount of heat generated inside the head. In this situation, it is necessary to take into consideration the environmental temperature and noise caused by the head, the stability of the output voltage of the head drive power source, etc. Conventionally, a method has been adopted in which, for example, a monitoring resistor is attached near the heating resistor element, and the voltage drop that occurs across the monitor resistor is used to adjust the voltage applied to the head. The power supply path is flexible.
Since the return path is long to the monitor resistor via the flat cable, there are separation points to ensure the stability of the applied voltage, and the power consumption within the head is maintained constant in response to changes in ambient temperature. There was nothing that had the functionality I wanted.

(Problems to be Solved by the Invention) Thus, the present invention solves the problem that it is difficult to avoid variations in the resistance value of the heat-generating resistive element of a thermal head no matter what technology is used, and this problem can be solved by classifying by grade. Identification can be easily realized on the sensing current-carrying path, and the power supply to the head can be automatically adjusted according to this identification, and it can also respond to environmental temperature changes, and the head can be easily replaced, and the head can be easily replaced. Even if the head is replaced, power can be automatically supplied to the head with almost no manual adjustment.

(Structure of the invention) In Fig. 1, a thermal head 1 is connected to a relay flat cable 2,
This is a diagram schematically representing a state in which power is supplied from a drive control power source assembled on a printed circuit board 6 via a flat cable 4, and the entire structure is shown along with a carriage (not shown) and a platen facing the head. It is installed so that it can be moved along. 11 is a heating resistor element patterned on the base of the henode, 22 is a current supply path to this heating resistor element, and 21 is a heating resistor element attached in the relay flat cable 2 close to the above current feeding path. This is a sensing current-carrying path in which a part of the current-carrying path is punched or cut so as to be visually visible from the outside in order to indicate the classification of grades such as A, B, and C. 6 is a relay flat cable 2 integrated with the above thermal head,
A connector for electrically contacting the flat cable 4 with each other; 5 a jack for connecting the flat cable to a printed circuit board 6; 7 a volume resistor for adjusting print density in a drive control power source to be described later; 8 a resistor for adjusting print density in the power source. The detection part is a temperature-sensitive detection element that detects the environmental temperature. Further, 41 is a current-carrying path in the flat cable 4 that is connected to the sensing current-carrying path 21 wired in the relay flat cable via a terminal (not shown) of the connector 3, and 42 is a current-carrying path in the thermal head 1. This is the current supply path within the flat cable.

Next, FIG. 2 shows an electric circuit system diagram in the schematic diagram of FIG. 1. R, , R5 are series resistors connected in series with the auxiliary power supply B through the cutting points CA, CB, etc. by pannonching or cutting the sensing current path 21' attached in the flat cable 2. It is a vessel. The inside of the drive control power source is mounted on a printed circuit board 6 in FIG.

To explain the operation of the thermal recording device of the present invention configured as described above, the thermal head 1 can be replaced as a head assembly integrated with the relay flat cable, and can be attached and detached using the connector 6. Since the grade can be visually confirmed from the outside, it is possible to immediately know which grade the thermal head belongs to.

If the cutting points CA and CB in the embodiment of FIG. 2 are both cut or punched, the transistor Q1
and series resistor R from auxiliary power supply B to the base pole of Q2-
4, no current flows in the sensing current path via R5, and therefore the detection transistor Q2. Both Qs are OFF
Since the state remains in the state, the voltage applied to the thermal head is applied to the resistor R++ and the voltage resistor 7. and the value determined by the 80 division ratio of the temperature sensitive detection element.When only the cutting point CB is cut, current flows only through the series resistor R4, and the detection is maintained in a completely saturated state. The transistor Q conducts the parallel terminal of the temperature sensing element 8, and a higher voltage than the previous voltage determined by the combined value of the temperature sensing element and the sensing resistor R6 is supplied to the thermal head. Further CA
When only the point is cut, the sensing current path 41 passes current through the series resistor R5 to the fully saturated transistor Q5, and immediately connects the sensing resistor R2 to both ends of the temperature sensing element. υ is in parallel state, and the thermal head is connected to a series resistor 凅 that carries current based on this combined resistance value.
The voltage drop at is added. In the above embodiment, the thermal head is classified into six stages, but it is also possible to freely classify the thermal head into more stages.

(Effects of the Invention) According to the present invention, in order to adjust the power supply current to the thermal head, the resistance of the heat-generating resistor element of the thermal head is set so that the relay flat cable integrated with the thermal head can be checked from the outside. The grade classification display based on the value is done by cutting, so from the perspective of the drive control power supply,
I decided to replace the thermal head, which is integrated with the relay flat cable, because it is a simple digital method to determine whether or not current flows into the heating resistor element.1. However, because the thermal head is cut into ranks at the manufacturing stage, it is not possible to measure the resistance value of the heating resistor every time it is replaced, and the drive control power supply maintains the power inside the thermal head at a constant level. It can be automatically adjusted to maintain the In addition, the monitor resistor element is not placed close to the heating resistor element on the same base as in the past, and the head and
If the flexible cable and printed circuit board can be moved together along the platen, the feedback loop of the drive control power source can be integrated into the detection section on the printed circuit board and placed together with the temperature sensing element within a short distance. Because I can understand that,
This has great industrial benefits, such as being able to suppress interference factors such as noise.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an embodiment of the apparatus of the present invention, and FIG. 2 is an electrical circuit diagram of the apparatus shown in FIG. 1° thermal head, 2 relay flat cable, 6
Connector, 4.7 Lanoto cable, 5 Jack, 6
Printed circuit board, 7. Volume resistor, 8゛ temperature-sensitive detection element, 110 heating resistance element, 21.41: Sensing current path, 22, 42 Current supply path, drive control power supply, C
A + Cn Cutting processing position. Applicant: Kyocera Corporation Broom 2. Amendment to figure procedure (voluntary): Q. 4, 1980 Commissioner of the Patent Office: Gakudono Shiga 1. Indication of case: 1982 Patent Application No. 105988 2. Name of the invention: 6. Amendment Relationship with the patent applicant case Address: 607 Telephone: 075 (592) 3851 None 5. The number of inventions will increase due to the amendment. 6. Specification subject to the amendment and attached drawings (Figure 1). 7. Details of the amendment attached. The description in the statement has been amended as follows. 1. On page 4, line 15, "all these together..." should be amended as follows. [The printed circuit board to which the drive control power supply unit is attached is fixed on the shear, but it is attached to the tip of a flexible flat cable together with a carriage (not shown)] 2. Page 6, line 19 [Q2Q3] IQ, and Q2]. 6. Correct "Q5" in line 10 of page 7 to "Q2". 4 Correct "this combined resistance value added." in lines 16 to 14 of page 7 as follows. [Resistor R1 + volume resistor 7 and temperature sensing element 8
A voltage determined by the division ratio of the combined resistance value of the detection resistor R2 and the detection resistor R2 is applied. By determining the value of the tabs 9R2-9R3 according to the difference in power supply voltage between ranks of heating resistive elements, in this embodiment, six levels of power supply voltage can be supplied to each of the heat generating resistor elements. "5, page 8, line 5, 1 heating resistor element" as "sensing current path for rank determination"
Correct to. 6. On page 8, lines 15 to 18, [carriage...old loop is] is corrected as follows. "The return loop of the drive control power supply cannot be reached directly by the head switch."

Claims (1)

[Claims] In a thermal printer in which a thermal printer head having a heating resistor element patterned on an insulating base is energized via a flexible flat cable to record prints, one end contacts a conductive terminal of the thermal head and the other end contacts a conductive terminal of the thermal head. The end forms the power supply path from the drive control power source for the thermal head - via the flexible flat cable and connector! - A relay flat cable and a pull are provided to form a current conducting path, and the resistance value of the heating resistor element is divided into multiple grades in addition to the current feeding path to the heating resistor element of the thermal head in the relay flat cable. A sensing current path formed through the detection section of the drive control power source and a series resistor is provided in proportion to the classification number, and the grade of the heating resistor element can be determined by cutting the sensing current path. In addition to displaying identification information, the drive control power source can be automatically adjusted so that the power generated within the thermal head based on the variation in the resistance value of the heat generating resistor element can be kept constant according to changes in the environmental temperature. A thermal recording device.