JPS61239955A - Printing head of dot printer excellent in heat dissipation effect and its preparation - Google Patents

Abstract

PURPOSE:To enhance heat dissipation effect by communicating an interior with the open air to make natural convection easy to generate, by providing the open part to a printing head so as to be communicated with the interior thereof and radially arranging the drive devices of printing hammers. CONSTITUTION:A printing head is divided into two printing head parts 7a, 7b each having N drive devices 6 equal to the number of printing hammers radially arranged to the crescent part thereof. When heat is generated from the coil or core of an electromagnet mechanism by continuous printing, the open air is flowed in the printing head from the gaps 3a of the drive devices 3 to take the quantity of heat generated in the interior 4 of the printing head and natural convection smoothly flowed out from an open part 5 is generated to enhance heat dissipation effect. This printing head is assembled by a conventional manufacturing means for dividing the printing head to simultaneously manufacture two heads before assembling both of them.

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a print head for a dot printer and a method for manufacturing the same.In particular, by devising the overall shape of the print head, the heat dissipation effect is dramatically improved. This makes it possible to efficiently manufacture a print head with excellent heat dissipation effect.

Conventional technology The print heads of dot printers can be roughly divided into impact type and non-impact type.The former print head uses wires or small protrusions that are struck via an ink ribbon to the print paper attached to the platen. , a plurality of dots are selectively arranged in a matrix on the same sheet of paper to print desired characters. There are the following two types of electromechanical means for applying impact energy to this wire or small protrusion as a printing hammer.

The first type is called a release type and is a permanent magnet.

The yoke, the electromagnetic mechanism, and the spring-supported armature constitute a magnetic path of the permanent magnet, and the coil of the electromagnetic mechanism is energized to generate reverse excitation flux against the magnetic flux of the permanent magnet, thereby canceling out the magnetic flux of the permanent magnet. The armature is released by spring elasticity, and a printing hammer provided on the armature or an arm attached to the armature performs a predetermined printing operation. The second type is called the suction type, and unlike the release type, it does not use a permanent magnet, but directly attracts the armature by energizing the electromagnetic mechanism and performs the specified printing operation with a printing hammer. It is. In any case, in these print heads, as shown in FIGS. 9 and 10, a plurality of printing hammers Lot are gathered in the central area, and each printing hammer 101 has an electromagnetic mechanism 102 as a component.
A configuration is adopted in which each drive device 103 is arranged radially. (Figures 9 and 10 show an example of a release type print head.) As the number of dot matrices increases as the character quality is required, the number of each driving device also increases. As the mechanical structure of the print head has become extremely densely packed, high-speed printing performance has become increasingly required, and under severe continuous printing conditions, current is generated by flowing through the coils of the electromagnetic mechanism. High heat is generated due to copper loss and iron loss caused by rapid changes in the magnetic flux passing through the core of the electromagnet mechanism, and the heat is trapped inside the highly densely mounted print head, causing various negative electromechanical effects on the print head. It has been pointed out that not only the printing function but also the lifespan is shortened. As a conventional method for solving this problem, a heat dissipation plate 104 is attached to the back of the print head as shown in FIG. 11 to dissipate the generated heat as efficiently as possible. (Refer to JP-A-59-202863, JP-A-59-207266, etc.) When continuous printing conditions become severe, the printing speed is automatically lowered to prevent the print head from becoming abnormally hot due to heat accumulation. Problems that the invention seeks to solveHowever, heat dissipation using a heat dissipation plate is often not very effective because the heat remains inside the print head, and is particularly effective against the generation of shock heat. However, the heat dissipation plate is sometimes ineffective, and the worst problem is that the mass of the print head as a whole increases due to the installation of the heat sink, which reduces the transport drive performance of the print head. In addition, it goes without saying that automatically lowering the printing speed goes against the demands for high-speed printing. Therefore, this invention solves the problem that the heat generated in the print head stays inside and that the cause is the electromagnetic mechanism. We focused on the fact that the print head is highly densely packaged radially around the print head, creating a structure that hardly generates natural convection of air, and the interior of the print head is communicated with the outside air to facilitate natural convection. It was created with the aim of providing a printhead with significantly improved heat dissipation, and also provides a highly efficient manufacturing method for manufacturing such a printhead.

Means for Solving the Problems The basic concept of the first invention will be explained with reference to FIG. 1, which shows a perspective view of a printing pad.

In the figure, the points indicated by l indicate the locations where the printing hammers are attached, and the printing hammers are individually arranged in the central region of each of the leaf springs or impact arms 2 arranged radially.

Independent driving devices 3 are disposed radially opposite each of the leaf springs or impact arms 2, and each driving device has an electromagnetic mechanism as its component. The print head is not arranged so that the driving device 3 completely covers the surrounding area in a radial manner, but has an opening 5 that communicates with the inside 4 of the print head to achieve the required number of prints/X number of marks. Each drive device 3 is arranged radially. Incidentally, the angle 5a of the opening portion 5 can be arbitrarily selected as long as the driving device 3 corresponding to the required printing hammer can be mounted.

Next, the basic concept of the second invention will be explained with reference to FIGS. 2 and 3, which are perspective views.

The present invention relates to the first aspect of the present invention, which is a method of manufacturing a print head of a dot printer having an excellent heat dissipation effect, in which drive devices for a required number of printing halves are radially arranged in a half-moon-shaped portion.

The manufacturing method of this invention consists of the following two steps.

1. The first step is to manufacture a print head for a dot printer in which drive devices 6 each having a number of printing hammers of 2N (N: an integer) are arranged radially in a perfect circle. The structure of this print head is similar to that which has been implemented in the past, but if the desired print head is for an N dot matrix, it must be composed of 2N drive devices 6. . The example shown in FIG. 2 has 32 drive devices, and the print head required in this manufacturing method is a 16-dot matrix print head. The second step is the step of dividing the print head made up of the 2N drive devices N6 into two, and by cutting along the plane shown as A in FIG. Each drive device 6 is divided into two 9N parts 7a and 7b, which are arranged radially in a half-moon shape. As a result, the print head is divided into two halves into half-moon-shaped printing rads 7 as shown in FIG.

In the print head of the first invention, even if heat is generated in the coil or core of the electromagnetic mechanism due to continuous printing, outside air flows in through the gap 3a of each drive device 3 and is generated inside the print head 4. A natural convection occurs in which the amount of heat is removed and the heat flows out smoothly from the opening 5, and heat from the print head can be dissipated extremely effectively. This makes it possible to obtain a dramatic heat dissipation effect compared to the conventional case in which each drive device covers the entire circumference.

In the method for manufacturing a print head of the second invention, the first step involves manufacturing a print head with twice the packing density, but this can be done by using conventional print head manufacturing means. In the second step, the assembled print head is divided into two parts, and the two print heads are moved first.

However, in the i2 process, if the print head is a wire tod printer, the selection of the two-part plane is arbitrary, but the printing hammer is composed of small protrusions, and the print is made by directly hitting the print head with the small protrusions. In some cases, the printing hammers must have special placement conditions, so if the printing hammers are formed first, the printing hammers of each print head after division will have to meet the special placement conditions. It is necessary to select a two-parting surface that has a All you have to do is process it first, and then attach the coil after the process.

Embodiment Next, an embodiment of the first invention will be described with reference to FIGS. 4 to 6. The print head shown in these figures is of the type that prints dots using small protrusions as printing hammers to form characters. A plan view and a sectional view of the overall configuration of this print head are shown in FIGS. 4 and 5, respectively. This printing head has driving devices M9 corresponding to the required number of printing hammers 8 arranged radially in a half-moon-shaped portion, and the upper surface of the provided driving devices 9 becomes an open portion 10 entirely. . The structure of each drive device 9 in this example is of a release type, and therefore consists of a permanent magnet 9a, a yoke 9b, an electromagnetic mechanism 90, a leaf spring 9d, and an armature 9e. By selectively energizing each independent electromagnet mechanism 9C, the magnetic flux of the permanent magnet 9a is canceled out, and the armature 9e is momentarily released from the state of attraction to the permanent magnet 9a, and the leaf spring is released. The printing hammer 8 is struck by the spring elasticity of 9d to print dots. In addition, the leaf spring 9 of the printing hammer 8
d, as shown in Figure 6.
The printing hammers 8 are arranged to have an integer multiple of a predetermined pitch in the axial (horizontal) direction and a predetermined pitch in the Y-axis (vertical axis) direction, and each printing hammer 8 is selectively moved while the print head is conveyed in the X-axis direction. The characters are constructed by printing dots driven by the dots.

. During the continuous printing process of this print head, the electromagnet mechanism 9
Since the open part 10 is provided on the entire top surface, the amount of heat generated at the This prevents the temperature of the entire print head from rising due to the removal of heat. In addition, as will be described later, this method also has six advantages in that efficient production is possible.

Next, a method for manufacturing a print head according to the second invention will be described. This manufacturing method relates to a method of manufacturing a print head in which a drive mechanism is disposed in the semicircular portion shown in FIGS. 84 and 5. The first step is the seventh step, which is a plan view.
As shown in FIG. 8, which is a diagram and a cross-sectional view, this is a process of manufacturing a print head in which drive devices each having a number of printing hammers of 2N (32 in this figure) are arranged radially in a perfect circular part. . In this case, the printing hammer 8 is arranged in the sixth
The arrangement described using the diagram is shown in FIG.
- It is symmetrical about the M-axis, or it is point-symmetrical about the center point 11.The second step is to 2-inch the entire print head in a plane including the M-M axis in FIG.
This is a dividing process. As a result, two half-moon-shaped print heads having eight (16 in this figure) print hammers 8 can be formed at the same time. It goes without saying that each divided print head has the same effect as described in the embodiment of the first invention.

Effects of the Invention In this invention, by providing an open part in the print head, natural convection occurs whenever heat is generated in the print head, and the heat dissipation effect of the print head is significantly improved. Enables continuous high-speed printing.

It should be noted that the provision of such an opening does not affect the electromechanical elements of each drive device of the print head.

Further, the manufacturing method of the present invention makes it possible to extremely efficiently manufacture a print head having the above-mentioned effects.

[Brief explanation of the drawing]

1 to 3 are perspective views showing the basic concept of this invention, FIG. 4 is a plan view showing an embodiment, and FIG. ), FIG. 6 is an enlarged view of the printing hammer arrangement area, FIG. 7 is a plan view of the print head, FIG. 8 is a sectional view thereof, and FIG. 9 is a plan view of the print head of the prior art. The figure shows a sectional view of the same, and FIG. 11 shows a sectional view. In each figure, ■ indicates the point where the printing hammer is attached, 2 is the leaf spring or impact arm, 3 is the drive device, 3a is the gap in the drive device, 4 is the inside of the print head,
5 is an open part, 5a is an angle of the open part, 6 is a drive device, 7 is a print head after division, 8 is a print hammer, 9 is a drive device, 9a is a permanent magnet, 9b is a yoke, 9C is an electromagnetic mechanism,
9d is a leaf spring, 9e is an armature, 10 is an open part, 1
1 indicates the center point. Agent Patent Attorney Toshi Mizui Kazu7 Printed print headset of figure G with figure 3 and figure 5

Claims (3)

[Claims] (1) In a print head in which a plurality of printing hammers are concentrated in a central area and drive devices for each printing hammer each having an electromagnetic mechanism as a component are arranged radially, an open portion communicating with the inside of the print head is provided. A print head for a dot printer with excellent heat dissipation effect, with each drive device radially arranged for the required number of printing hammers. (2) A print head for a dot printer having an excellent heat dissipation effect as set forth in claim (1), wherein each driving device of a required number of printing hammers is arranged radially in a half-moon-shaped portion. (3) Print head of a dot printer with excellent heat dissipation effect, in which multiple printing hammers are concentrated in the central area, and drive devices for the required number of printing hammers each consisting of an electromagnetic mechanism are arranged radially in a half-moon shape. In the manufacturing method of 2
A process of manufacturing a print head of a dot printer in which drive devices each having a number of N (N: an integer) number of printing hammers are arranged radially in a perfect circle, and a process of manufacturing a print head of a dot printer in which each drive device each having a number of N printing hammers is arranged in a perfect circle. A method for manufacturing a print head for a dot printer having an excellent heat dissipation effect, comprising the step of dividing the print head into two print head parts arranged radially in a half-moon shape.