JPH03288656A - Impact dot head - Google Patents

Abstract

PURPOSE:To detect the temp. of an actuator in an optimum position by a method wherein a temp. detector fixing part of a flexible print circuit board is projected in an arm form, a temp. detector is fixed on the top end thereof, and the circuit board is folded to cover the fixed conductor part of the temp. detector. CONSTITUTION:In an impact dot head in use, a temp. detector fixing part 17a of a flexible print circuit board 17 is projected in an arm form, a temp. detector 18 is fixed on the top end part thereof, and the circuit board 17 is folded to cover the fixed conductor part. In this manner, the temp. detector 18 can be disposed on a position optimum for detecting the temp. of an actuator 6. Furthermore, the fixed conductor part can be protected in a simple manner, and the impact dot head can be improved in performance and assembleability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the protection of the shape of a power transmission line board and the fixed conductor portion of a temperature sensor in an impact dot head.

[Prior Art] In the conventional art, it has been known that the power transmission line board of the impact dot head and the fixed conductor portion of the temperature sensor are covered with an insulator such as a polyester plate.

[Problems to be Solved by the Invention] However, when covering the fixed conductor part between the temperature sensor and the power transmission line board with an insulating plate, the position of the fixed conductor part depends on whether the fixed conductor part is covered with the insulating plate or not. Since the arrangement is determined, the temperature detector cannot be placed at the optimal position for detecting the temperature of the actuator, as shown in FIG. 5, and overheating of the actuator cannot be detected and the actuator may burn out. In order to avoid this problem, the performance of the impact dot head must be lowered, such as by limiting the number of dots that can be printed per unit time. In addition, to avoid such problems, there are measures such as covering the signal wire of the temperature sensor and arranging the temperature sensor at the optimal position for temperature detection, as shown in Figure 6. The signal wire must be coated with sufficient strength. Another disadvantage is that it is difficult to secure the signal wires attached to the clothing, making assembly work difficult.

Therefore, the present invention compensates for these drawbacks of the conventional technology and provides easy assembly.
The purpose is to provide a high-performance impact dot head.

It is characterized in that the component circuit board is bent and used so as to cover the fixed conductor part.

[Function] The flexible printed circuit board and temperature sensor of the impact dot head configured as described above are arranged so that the temperature sensor attached to the arm part of the flexible printed circuit board and its tip can optimally detect the temperature of the actuator. Furthermore, by bending the flexible printed circuit board so that it covers the fixed conductor part of the temperature sensor, the fixed conductor part can be easily protected and the performance of the impact dot head can be improved as well as the ease of assembly. .

[Means for Solving the Problems] In order to solve the above problems, the impact dot head according to the present invention has a flexible printed circuit board in which the temperature sensor fixing portion of the flexible printed circuit board protrudes like an arm, and the temperature sensor is fixed to the tip of the flexible printed circuit board. Example 1 Examples of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of the impact dot head of the present invention. The armature 6 with the printing wire 10 fixed to its tip is joined to the leaf spring 8, and the printing wire 10 is connected to the wire guide 12.
Guidance is maintained by. The leaf spring 8 is sandwiched and fixed between the spring pressing plate 9 and the side yoke 5, and is connected to the yoke plate 4 by
, the permanent magnet 3, and the base plate 2 are fixed in a stacked state. A plurality of cores 1 are arranged substantially circumferentially on a base plate 2, facing the armature 6, and a magnet coil 7 is wound around the core 1. Both ends of the winding of the magnet coil 7 are soldered to a flexible printed circuit board 17 through holes or slits (not shown) provided in the base plate 2, and the other end of the flexible printed circuit board 17 is soldered to the flexible printed circuit board 17. Plugged into an unshown connector. An inner circumferential ring 11 is disposed inside the core 1 arranged on the circumference, and a heat transfer member 13 having a cylindrical convex portion is disposed on the inner circumference of the inner circumferential ring 11. The outer peripheral surface of the shaped convex part and the inner peripheral ring 11
is in contact with the circumferential surface of and is in contact with the heat sink 15. The heat transfer member 13 and the heat sink 15 are fixed to the base plate 2 with screws 16. A temperature detector 18 for detecting the temperature of the magnet coil 7 is soldered to the flexible printed circuit board 17 and the temperature detector fixing arm 17-a, and is disposed between the heat transfer member 13 and the coil 7. Next, the operation will be explained. Amateur 6 during non-printing standby
is attracted to the core 1 by the magnetic flux generated by the permanent magnet 3, so the leaf spring 8 is biased and stores strain energy. During printing, the armature 6 is released by passing current through the magnet coil 7 in a direction that cancels the magnetic flux of the permanent magnet 3, and the printing wire 10 fixed to the end of the armature 6 is moved to the wire guide 12 by the strain energy of the leaf spring 8. Since it protrudes while being guided, it collides with an ink ribbon and paper (not shown), forming dots on the paper surface. After the dot is formed, the armature 6 is again attracted and held by the core 1 by the repulsive force of the printing wire 10 upon collision and the attractive force of the permanent magnet 3, and the printing process is completed. In this process, the impact dot head generates heat due to Joule loss caused by the current flowing through the magnet coil 7 and iron loss generated in the magnetic circuit. FIG. 2 is a perspective view showing the positional relationship of the flexible circuit board 17 and the temperature detector 18 in the impact dot head according to the embodiment of the present invention. After fixing the temperature sensor 18, as shown in FIG. 3, which is a view of FIG. The printed circuit board 17 is bent and the temperature sensor fixed portion protection portion 17-b is used as an insulator. FIG. 4 shows the flexible printed circuit board 17 of this embodiment, which is provided with a temperature sensor fixing arm part 17-a and a fixed part protection part 17-b, and has a structure that can be bent according to the broken line. In this embodiment, application to an impact dot head has been explained, but it is obvious that the present invention can be applied to other types of print heads having an actuator and using a flexible printed circuit board as a substrate.

[Effects of the Invention] The present invention protrudes the temperature sensor fixing portion of the flexible printed circuit board of the impact dot head in the form of an arm, fixes the temperature sensor to the tip thereof, bends the flexible printed circuit board, and fixes the temperature sensor fixed conductor portion. By covering the temperature sensor, the degree of freedom in installing the temperature sensor increases, allowing for optimal placement for detecting the temperature of the actuator, and eliminating the need for special materials or means to protect the insulation of the fixed conductor. This has the effect of improving the printing performance, reliability, and assembly performance of the impact dot head.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an impact dot head showing an embodiment of the present invention. FIG. 2 is a perspective view showing the positional relationship of the flexible circuit board and temperature sensor in the impact dot head according to the embodiment of the present invention. FIG. 3 is an enlarged view of the solder joint between the temperature sensor and the flexible printed circuit board shown in FIG. 2, viewed from the nose side of the impact dot head. FIG. 4 is a diagram showing the state of the flexible printed circuit board of this embodiment before the temperature sensor is fixed. FIG. 5 is a diagram showing a conventional example in which a temperature sensor is fixed to a printed circuit board. FIG. 6 is a diagram showing a conventional example in which the signal line of a temperature detector is coated with an insulating coating and made longer. 116. Core 262. Base plate 310. Permanent magnet 410. Yoke plate 51. , side yoke 6
16. Amateur 711. Magnet coil 811. Leaf spring 911. Spring pressing board 10,,,
Printing wire 11, inner ring 12. ,,wire guide 13,
, Heat transfer member 14 , Nose 15 , Heat sink 16 , Screw 17 , Flexible printed circuit board 17-a, Flexible printed circuit board Temperature detector fixing arm 17-b, Temperature Detector fixed part protection part 18, Temperature detector 18-a, Temperature detector signal line 19, Solder joint part

Claims (2)

[Claims] (1) In an impact dot head that drives a print wire attached to the actuator by selectively energizing a plurality of actuators and forms dots by impact force on a print medium, electrical energy is applied to the actuators. A temperature sensor is provided to detect the temperature of a flexible printed circuit board that is a power transmission line board and an actuator, and an arm-shaped protrusion is provided on the flexible printed circuit board, and a fixed part of the temperature sensor is attached to the arm-shaped protrusion. The impact dot head is characterized by being installed in the section. (2) An impact dot head characterized in that a fixed conductor portion of a temperature sensor fixed to a flexible printed circuit board is bent to cover the flexible printed circuit board.