JPH069961U - Wire dot print head - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent high temperature due to printing drive and enable high density printing for a long time. [Structure] A power supply side power supply connector 20 provided on the print head main body side corresponding to the fin 3, an elastic locking piece 25 formed on the fin 3, and attached to the fin 3 via the elastic locking piece 25. , A power supply connector 3 on the receiving side that is electrically coupled to the power supply connector 20 on the supplying side at the time of this mounting
2, and a fan unit 22 having an electric fan 29 electrically connected to the receiving side power supply connector 32. When the fan unit 22 is attached, the supply side power supply connector 20 and the receiving side power supply connector 32 are connected to each other. The electric fan 29 that is electrically connected can be driven by using the power source of the print head main body side.
The fins 3 can be forcibly cooled by the wind generated by driving the.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an armature wire dot print head having a fixed wire.

[0002]

[Prior art]

 Conventionally, an impact printer that drives an armature to which a print wire is fixed, impacts the print medium through the ink ribbon with this print wire, and prints with that force has a high degree of freedom in the print medium. Since it is relatively inexpensive, it is used in various fields including output devices such as information processing systems. The impact printer includes a wire dot printing type, a plunger type, a vane charge type, a clapper type, and the like. Among them, the spring charge type supports an armature to which a printing wire is fixed by a bias leaf spring so that the armature can swing freely, and the armature is made of a permanent magnet against the elastic force of the bias leaf spring in advance. It has a structure in which it is attracted to the core by a magnetic action, and when printing, the coil wound around the core is excited to generate a magnetic flux in the direction opposite to that of the permanent magnet, thereby opening the armature. Since this structure has good high-speed responsiveness, it has been widely adopted in recent years when high-speed printing is required.

FIG. 10 is a schematic cross-sectional view of a conventionally known spring-charge type wire dot print head. In the wire dot print head 101 in FIG. 10, a base 104, a permanent magnet 105, a pedestal 106, a spacer 107, a bias leaf spring 108, and a yoke 109 are sequentially laminated between the guide frame 102 and the fin 103, These are fixed together by a clamp 112.

Further, in detail, the bias leaf spring 108 is formed as a ring-shaped flat plate, and the flexible portion 108b is integrally formed in a state of protruding from the ring-shaped body portion toward the center. The armature 114 made of metal and having the print wire 113 fixed thereto is attached to the flexible portion 108b. A core 115 is provided at the center of the base 104, and a coil 116 is wound around the core 115.

Reference numeral 119 is a substrate for energizing the coil 116, 120 is a space sheet for positioning the substrate 119, 121 is a thermistor for temperature detection, and 122 is a thermal conductive material for covering the coil 116 and the thermistor 119. It is a good filler.

Next, the operation of the wire dot print head 101 will be described. First, in the wire dot print head 101, a magnetic circuit is formed in which the magnetic flux of the permanent magnet 105 returns to the permanent magnet 105 through the base 106, the spacer 107, the yoke 109, the armature 110, the core 115, and the base 104. It

When the coil 116 is not energized, the armature 114 is attracted to the core 115 while biasing the bias leaf spring 108, and strain energy is accumulated in the bias leaf spring 108, which is in a biased state. 113 is drawn into the nose portion 102a of the guide frame 102. FIG. 10 shows this state.

On the other hand, when a current is passed through the coil 116 to excite it, a magnetic flux in the direction opposite to the exciting circuit is generated. Then, the force of attracting the armature 114 decreases, the strain energy accumulated in the bias leaf spring 108 is released, and the bias leaf panel 108 returns. Then, upon this return, the print wire 113 fixedly attached to the tip of the armature 114 projects from the nose portion 102a of the guide frame 102, and presses the ink ribbon and the print medium (not shown) against the platen. With this, it is possible to print characters and graphic patterns.

Further, the heat generated in the coil 116 that is consumed by energizing the coil 116 during printing is released by the fins 103, and the heat stored inside is an epoxy resin having good thermal conductivity. The temperature inside the wire dot print head 101 that is transmitted to the thermistor 121 by the filler 122 such as the above and rises at the part of the thermistor 121 is monitored, and the temperature of the coil 116 is controlled and maintained below the heat resistant temperature.

In this way, after the armature 114 is once opened, the power supply to the coil 116 is cut off again. Then, the armature 114 is again sucked and held by the core 115 together with the print wire 113 that has returned after impacting the print medium.

[0011]

[Problems to be solved by the device]

 However, in the structure of the conventional wire dot print head described above, when printing is performed with a large number of prints in a unit area, that is, high-density printing, the temperature of the wire dot print head 101 is instantaneously changed by the heat generated by the wire dot print head 101. The coil 116 may rise and eventually reach the heat resistant temperature of the coil 116 and be damaged. In addition, when a semiconductor such as a driver is provided inside, the temperature rises from 120 ° C, which is the heat-resistant temperature of the semiconductor, to 200 ° C, which may lead to damage to internal components. . Therefore, in general, when the temperature inside the wire dot print head exceeds a certain temperature, printing is stopped, the temperature is waited for the temperature to drop, and when the temperature drops again, the printing control is repeated to prevent damage. However, in that case, there is a problem that the number of prints performed in a unit time, that is, the print amount is reduced, and the printer is a high-speed printer, and the printer is stopped for a long time, resulting in a decrease in the print amount.

The present invention has been made in view of the above problems, and an object thereof is to provide a wire dot printing head capable of preventing a temperature rise due to printing drive and enabling high-density printing for a long time. To do.

[0013]

[Means for Solving the Problems]

 In order to achieve the above object, the wire dot print head according to the present invention radiates heat through a fin integrally attached to the print head main body, and an electric fan for forcibly cooling the fin is detachable. It was installed in. In addition, the supply side power supply connector provided on the print head main body side corresponding to the fin, the engaging portion formed on the fin, and being attached to the fin via the engaging portion, When a configuration is provided in which a power supply side power connector that is electrically coupled to the power supply side power connector at the time of mounting and a fan unit that has an electric fan electrically connected to the power supply side power connector are provided, the electric fan If a fan unit is attached via the engaging part, the power supply side power supply connector is electrically connected to the power supply side power supply connector, and the power supply on the print head body side is used to operate the electric fan. It can be driven. Furthermore, if a releasable protective member is provided to cover the power supply connector on the receiving side from the outside, foreign matter may come into contact with the power connector on the receiving side in a structure without a fan unit, resulting in a short circuit accident. Can be prevented.

[0014]

[Action]

 According to this configuration, if an electric fan is attached as necessary, the electric fan can apply air to the fins to forcibly cool the fins, which improves the heat dissipation efficiency of the fins and reduces internal components. It is possible to prevent it from reaching the heat resistant temperature. This prevents damage to internal parts and enables high-density printing for a long time.

[0015]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a side view of a wire dot print head shown as an embodiment of the present invention, FIG. 2 is a bottom view thereof, and FIG. 3 is a schematic sectional view thereof. The wire dot print head 1 shown in FIGS. 1 to 3 is of a spring charge type, and includes a base 4, a permanent magnet 5, a pedestal 6, a spacer 7, a bias leaf spring 8 and a space between the guide frame 2 and the fins 3. The yokes 9 are sequentially laminated and provided, and they are integrally fixed by a clamp 10.

More specifically, the bias leaf spring 8 is formed as a ring-shaped flat plate, and the flexible portion 8b is integrally formed in a state of protruding from the ring-shaped body portion toward the center. A metal armature 12 having a print wire 11 fixed thereto is attached to the flexible portion 8b. A core 13 is provided at the center of the base 4, and a coil 14 is wound around the core 13.

The coil 14 is electrically connected via a space sheet 15 to a printed wiring terminal (not shown) on a substrate 16 attached to the base 4. Further, the board 16 integrally has an external power source connecting connector portion 16a (see FIG. 2) that is connected to an external power source, and is electrically connected to the external power source via the external power source connecting connector portion 16a. Is connected. Further, a thermistor 17 for temperature detection is arranged on the upper side of the substrate 16 together with the coil 14 and the like in a state of being solidified with a filler 18 having good thermal conductivity. On the other hand, on the lower surface side of the substrate 16, a supply side power supply connector 20 having power supply terminals 19a and 19b electrically connected to a printed wiring terminal (not shown) leading to the external power supply connection connector portion 16a is attached.

The fins 3 are formed in a low-profile box shape having an open upper surface. Then, with the substrate 16 stored, the upper opening side is placed in contact with the base 4, and the locking claws 21 provided on the peripheral surface of the fin 3 are hooked on the guide frame 2 at one end. The clamp 10 is attached to the base 4 side so as to be hooked in an engagement hole (not shown) on the other end side of the clamp 10. A fan unit 22 can be attached to the fin 3.

4 to 9 show detailed structures of the fin 3 and the fan unit 22. Therefore, the structures of the fin 3 and the fan unit 22 will be further described with reference to FIGS. 4 to 9. First, the fin 3 is provided with a connector hole 23 communicating with the supply power connector 20 and a ventilation hole 24 communicating with the fin 3 on the side surface of the supply power connector 20 facing the power terminals 19a and 19b. At the same time, a pair of elastic locking pieces 25, 25 having locking claws 25a at their ends are integrally formed on both left and right sides sandwiching the connector hole 23 and the ventilation hole 24. The locking claws 25a are provided so as to face each other inward.

Further, as shown in FIGS. 6 to 9, a pair of rail portions 26 are provided inside the side surface, and a plate-like member as a protective member is provided between the pair of rail portions 26, 26. The protective plate 27 made of plastic is slidably attached. Among these, the pair of rail portions 26, 26 are formed in a groove shape having a substantially L-shaped cross section, and their opening portions are opposed to each other. On the other hand, the protective plate 27 is disposed in the grooves of both rail portions 26, 26, respectively, and is guided by the pair of rail portions 26 so that the connector hole 23 is formed as shown in FIG. Can be slid between a closed position in which the connector is closed and an open position in which the connector hole 23 is opened as shown in FIG. The small holes 28 (see FIGS. 6 and 7) formed in the protection plate 27 are holes for inserting and engaging a jig or the like (not shown) when the protection plate 27 is moved.

The fan unit 22 includes a housing 30 in which an electric fan 29 is provided. When the electric fan 29 rotates, the wind generated by the electric fan 29 and the ventilation holes 24 on the fin 3 side are generated. It is in a state of being blown out from the lower surface opening of the housing 30 provided correspondingly. Further, the housing 30 has a suction hole 33 for taking in air from the outside when the electric fan 29 is driven, and a plurality of holes (four in this embodiment) for letting out the air blown previously. Ventilation holes 31 and are formed. Further, the fan unit 22 is provided with a receiving side power supply connector 32 corresponding to the connector hole 23 and the supply side power supply connector 20, and the receiving side power supply connector 32 has a power supply terminal 19 a of the supply side power supply connector 20. , 19b, the power supply terminals 33a, 33b are provided so as to project downward, and the power supply terminals 33a, 33b are electrically connected to the electric fan 29. In addition, on the lower end side of the housing 30, an engagement plate portion 34 is integrally formed between the elastic engagement pieces 25, 25 and retained by being engaged with the engagement claw 25a.

The method of using the fin 3 configured as described above may be used with or without the fan unit 22 attached, and may be used with or without the fan unit 22 attached. Can be selected according to the printing mode. When the fan unit 22 is used in the structure, the fins 3 are attached to the base 4 on the print head main body side by the clamps 10, and the protection plate 27 is moved to the open position to form the connector hole 23. Leave it open. Then, the power supply terminals 19a and 19b of the supply-side power supply connector 20 on the substrate 16 on the print head body side are seen through the connector hole 23.

Next, as shown in FIG. 9, the power supply terminals 19a and 19b of the power supply side connector 20 are made to correspond to the power supply terminals 33a and 33b of the power supply side connector 32, and the elastic locking pieces 25 and 25 are connected to each other. The locking plate portion 34 is made to correspond to, and the fan unit 22 is pressed against the fin 3. Then, the pair of elastic locking pieces 25 are elastically deformed and temporarily released to the outside, and when the locking plate portion 34 has finished passing the locking claw 25a, the locking plate portion 34 is locked. 25a is engaged and held. At the same time, the power supply terminals 33a and 33b of the receiving power supply connector 32 are inserted into and electrically engaged with the power supply terminals 19a and 19b of the supply power supply connector 20, and the electric fan 29 is connected to the supply power supply connector. It is electrically connected to the wiring on the board 16 through the power supply connector 20 and the power supply connector 32 on the receiving side, and receives the DC voltage of 35 V supplied from the outside through the connector 16a for connecting the external power supply of the board 16 to drive the rotation. It becomes possible to do. 1 and 2 show the fan unit 22 thus mounted.

When the attached fan unit 22 is to be removed again, each elastic locking piece 25 is elastically deformed and tilted outward until the locking plate portion 34 and the locking claw 25a are disengaged. In this state, the fan unit 22 can be removed by pulling it out in the opposite direction to when it was attached. After the removal, the protective plate 27 is placed in the closed position, and the connector hole 23 is closed by the protective plate 27.

On the other hand, when the fan unit 22 is used with the fan unit 22 removed, that is, when the fan unit 22 is not attached, the protection plate 27 is placed in the closed position, and the protection plate 27 keeps the connector hole 23 closed. Leave. As a result, even if the fan unit 22 is not attached, the power supply terminals 19a and 19b of the power supply connector 20 on the supply side are closed by the protection plate 27. It is possible to prevent a foreign substance such as metal from entering the terminals 19a and 19b and causing a short circuit accident. The ventilation holes 24 here may be left open, or may be closed separately by preparing a separate cap. If left open, the ventilation holes 24 Since the heat to keep the muffler can be released through the ventilation holes 24, the heat dissipation is improved.

Next, the operation of the wire dot print head 1 will be described. In the present embodiment, as shown in FIGS. 1 and 2, a case where the fan unit 22 is attached to the fin 3 will be described. First, in this wire dot print head 1, a magnetic circuit is formed in which the magnetic flux of the permanent magnet 5 returns to the permanent magnet 5 again through the base 6, the spacer 7, the yoke 9, the armature 12, the core 13 and the base 4. .

When the coil 14 is not energized, the armature 12 is attracted to the core 13 while biasing the bias leaf spring 8, and the bias energy is accumulated in the bias leaf spring 8 and is in the bias state. The wire 11 is drawn into the nose portion 2a of the guide frame 2. FIG. 1 shows this state.

On the other hand, when a current is passed through the coil 14 to excite it, a magnetic flux in the direction opposite to the exciting circuit is generated. Then, the force of attracting the armature 12 decreases, the strain energy accumulated in the bias leaf spring 8 is released, and the bias leaf spring 8 returns. Then, upon this return, the printing wire 11 fixedly attached to the tip of the armature 12 projects from the nose portion 2a of the guide frame 2, and presses the ink ribbon and the printing medium (not shown) against the platen. As a result, characters and graphic patterns can be printed.

In this way, after the armature 12 is once opened, the coil 14 is de-energized again. Then, the armature 12 is sucked and held again by the core 13 together with the printing wire 11 that has returned after impacting the printing medium.

The heat generated in the coil 14 by energizing the coil 14 at the time of printing is transmitted to the thermistor 17 by the filler 18 such as an epoxy resin having a high thermal conductivity, and the thermistor 17 part. The rising temperature in the wire dot print head 1 is monitored, and the temperature of the coil 14 is controlled and maintained below the heat resistant temperature. When the temperature inside the wire dot print head 1 reaches a certain temperature or higher, a drive current is supplied to the electric fan 29 via the substrate 16 and the electric fan 29 is driven. Then, the wind generated by the electric fan 29 is blown into the space between the fins 3 and the base 4 and the substrate 16 through the ventilation holes 24 to release the heat generated therebetween, and the fins 3 are forced from the inside. Dissipate heat while cooling.

Therefore, in the wire dot print head 1, the electric fan 29 blows air on the fins 3 attached to the print head main body to forcibly cool the fins 3, so that the fins 3 can dissipate heat efficiently. It is possible to improve and prevent the internal parts from reaching the heat resistant temperature. As a result, damage to internal parts can be prevented and high density printing can be performed for a long time. In addition, the power supply side connector 20 provided on the print head main body side corresponding to the fin 3, the elastic locking piece (engaging portion) 25 formed on the fin 3, and the elastic locking piece 25 And a receiving side power supply connector 32 which is electrically coupled to the power supply terminals 29a and 29b of the supply side power supply connector 20 at the time of this mounting, and electrically connected to this receiving side power supply connector 32. Since the fan unit 22 having the electric fan 29 and the fan unit 22 having the electric fan 29 are provided, when the fan unit 22 is attached only when the electric fan 29 is required, the receiving side power connector 32 is attached to the supplying side power connector 20. The electric fan 29 can be electrically connected and the power source of the print head main body can be used to drive the electric fan 29. Further, when the fan unit 22 is not attached, the power receiving side power connector 20 can be covered with the protection plate 27 from the outside, so that the power receiving side power connector 20 may not come into contact with foreign matter. It is possible to prevent a short circuit accident.

In the above embodiment, the structure in which the air generated by the electric fan 29 is blown into the fins 3 through the ventilation holes 24 to forcibly cool the air is disclosed. However, the structure in which the air is blown directly to the outside of the fins 3 may be used. There is no such thing.

[0033]

[Effect of device]

 As described above, according to the wire dot printing head of the present invention, if an electric fan is attached as necessary, the electric fan can blow air onto the fins to forcibly cool the fins. This improves heat dissipation efficiency and prevents internal parts from reaching the heat resistant temperature. This can prevent damage to internal parts and can be expected to produce high-density printing over a long period of time.

[Brief description of drawings]

FIG. 1 is a side view of a wire dot print head shown as an embodiment of the present invention.

FIG. 2 is a bottom view of the above print head according to the present embodiment.

FIG. 3 is a schematic cross-sectional view of the same print head according to the present embodiment.

FIG. 4 is a side view of the same print head as shown in the state before the fan unit is attached.

FIG. 5 is a top view of a single fan unit.

FIG. 6 is an enlarged view of a main part of the same print head as shown with the connector hole opened.

FIG. 7 is an enlarged view of a main part of the same print head with the connector hole closed.

8 is a cross-sectional view taken along the line AA of FIG.

FIG. 9 is an explanatory view of mounting the fan unit.

FIG. 10 is a schematic sectional view of a conventional same print head.

[Explanation of symbols]

 1 Wire Dot Print Head 3 Fin 16 Substrate 20 Supply Side Power Connector 22 Fan Unit 27 Protection Plate (Protection Member) 29 Electric Fan 32 Receiving Side Power Connector

Claims (3)

[Scope of utility model registration request] 1. A wire dot print head for radiating heat through a fin integrally attached to a print head main body, wherein an electric fan for forcibly cooling the fin is detachably provided. 2. A wire dot print head for radiating heat through a fin integrally attached to the print head main body, wherein a supply side power supply connector provided on the print head main body side corresponding to the fin, and a connector formed on the fin. A mating part, a receiving side power connector that is detachably attached to the fin via the engaging part, and is electrically coupled to the supply side power connector at the time of this attachment, and an electrical connection with the receiving side power connector. And a fan unit having an electric fan connected to the wire dot printing head, the fin being forcibly cooled by the electric fan. 3. The wire dot print head according to claim 2, further comprising a releasable protection member that covers the power supply connector on the receiving side from the outside.