JP2923726B2 - Printing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus having a shuttle unit having a reciprocating mechanism for performing printing, such as a dot line printer.

In a dot line printer or the like,
The temperature of the shuttle unit rises when a heavy print unit equipped with a print head is reciprocated at high speed during printing, and the temperature of the print unit rises when printing is performed. For this reason, the shuttle frame of the shuttle unit and the head frame of the printing unit are thermally deformed, and the printing quality is reduced.

[0003]

2. Description of the Related Art FIG. 18 is a front view showing the essential structure of a conventional shuttle mechanism. A head frame 1 of a printing unit is connected to a shuttle frame 2 of the shuttle unit by two screws (only a center line is shown). A recess 3 is formed in a central portion of the shuttle frame 2 other than the joint at both ends. 4 is a stay shaft. In the dot line printer device using this shuttle mechanism, the printing unit performs printing while performing a linear reciprocating motion, and when printing of one line is completed, the sheet is line-feeded and continuous printing is performed.

[0004]

By the way, the reciprocating motion of the printing unit is performed by energizing the coil in a magnetic field created by a permanent magnet installed below the coil mounted on the shuttle unit, thereby causing framing. According to the rule of the left hand, a thrust is generated in the coil, and the shuttle unit to which the coil is attached moves to make use of the principle of the linear motor.

During this movement, the temperature of the coil rises and the temperature of the shuttle frame rises accordingly. On the printing unit side, as shown in FIG. 19, the armature 13 attracted to the core 12 by the attractive force of the permanent magnet 11 causes a current to flow through the coil 14 in a direction to cancel the attractive force of the permanent magnet 11. As a result, the printed wire 16 welded to the tip of the armature 13 prints dots on the paper 19 on the platen 18 via the ink ribbon 17 by the stored force of the leaf spring 15 supporting the armature 13. As a result, the coil temperature of the print head rises, and this causes
The temperature of the storage unit increases.

In the conventional structure, the shuttle frame and the head
Frame is fixed at both ends two places, due to the presence of the recess in the shuttle frame side, the head frame and Shah
Between the two frames Torr frame has gaps, header
Unit is thermally isolated . Therefore, headyu
The route for radiating heat on the knit side is from the head frame.
Route and the both ends of the head frame to radiate heat directly into the air
Since there is only a route to radiate heat from the shuttle frame to the shuttle frame,
Efficient heat dissipation is not performed, and the entire head unit is heated to high temperatures
Become. As a result, the head unit is thermally deformed in combination with the reduction in rigidity due to the presence of the recess on the shuttle frame side, and the printing quality is reduced.

Therefore, the present invention is directed to the head unit side.
By efficiently radiating the generated heat, the head unit
Temperature rise on the side and suppresses thermal deformation of the head unit
And stabilize the printing quality .

[0008]

In order to achieve the above object, the present invention provides a print head for printing and a print head.
A printing unit having a head frame supporting mechanism for reciprocating the shuttle frame and said printing unit
In the printing apparatus having a shuttle unit having,
The entire bottom surface of the head frame and the head frame
The upper surface of the shuttle frame having an upper surface having an area larger than the bottom surface is brought into close contact with the shuttle frame , and
(1st structure) characterized in that the torque frame and the head frame are joined at two positions on both ends of the head frame .

Also, a print head for performing printing, a print head
Unit having a head frame for supporting a printer, a shuttle frame and a machine for reciprocating the printing unit
Configuration Te printer odor <br/> having a shuttle unit having the head frame with the entire bottom surface of the head frame
The head frame and the shuttle frame having an upper surface having an area larger than the bottom surface of the
A second feature is that the shuttle frame and the shuttle frame are connected at two locations at both ends of the head frame and at least one location therebetween.

Also, a print head for performing printing, a print head
Unit having a head frame for supporting a printer, a shuttle frame and a machine for reciprocating the printing unit
Configuration Te printer odor <br/> having a shuttle unit having a bottom surface of said head frame and said head frame
A third configuration is characterized in that the shuttle frame having an upper surface with a larger area is integrally formed .

[0011]

In the case of the first configuration, the two frames are opposed to each other.
Because the whole is closely attached and joined at two places at both ends,
The heat radiating directly from the head frame to the shuttle frame
Increase the rate. That is, the shuttle frame is
Head frame from the shuttle frame.
The amount of heat released to the frame increases, and the temperature on the head unit side increases.
Ascent can be controlled. Therefore, the head unit
Printing quality can be stabilized by suppressing thermal deformation. Furthermore, the tightness between the head frame and shuttle frame
Due to the increase in adhesion, friction generated on the contact surface
The force increases, which increases the mechanical rigidity of the headframe.
The effect of suppressing thermal deformation of the head unit
There is also. In the case of the second configuration, in addition to both ends,
By fixing, the shuttle frame and head frame
The adhesion of the arm is further increased.

Further, in the case of the third configuration, since the shuttle frame and the head frame are formed integrally ,
Transfer the heat of the paddle frame to the shuttle frame.
Head-free
It is possible to reliably suppress deformation of the arm , which is even more effective.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

Before describing the shuttle mechanism of the present invention,
First, the configuration and operation of a line printer to which the present invention is applied will be described. FIG. 4 is a perspective view of the line printer.
FIG. 5 is a plan view of the same, and FIG. 6 is a sectional side view of the same.

Reference numeral 101 (not shown in FIG. 4) is a base frame attached to a casing (not shown), and stay shafts 102 and 103 extending in the left-right direction of FIGS. Have been. A shuttle frame 112 on which a printing unit 111 is mounted is slidably fitted to the stay shaft 102 near the center. The shuttle frame 112 is connected to the base frame 10
1 and supported by a first stay shaft 102 and a roller 113 that can run on the first stay shaft 102.

As shown in FIG. 7, the print unit 111 includes a 24-pin print head 80 (six print elements 81 are arranged in two stages in front and rear and symmetrically up and down) as shown in FIG. The print wires of each print head 80 are guided by a wire guide 82. In FIG. 8, Nos. 1 to 12 written on the respective print heads are head module numbers.

A yoke 114 made of an iron plate is fixed to a lower portion of the shuttle frame 112. On the lower surface of the yoke 114, eleven rectangular plate-like permanent magnets 115 whose thickness direction is a double pole are provided with a first permanent magnet 115. The stay shaft 102 is mounted side by side in the axial direction. The permanent magnet 115 is slightly wider than the width of the print head 80, and is arranged continuously so that the N pole and the S pole are alternately arranged as shown in FIG. In addition, a gap is provided between the permanent magnets 115 at both ends and nine permanent magnets 115 adjacent to the central portion.

As described above, the shuttle frame 112, the yoke 114, and the permanent magnet 115 are integrally formed to form the first
A shuttle unit 110 movable along the stay shaft 102 is formed, and the shuttle unit 110 and the printing unit 111 constitute a shuttle mechanism.

On the other hand, a large number of electromagnetic coils 11 are placed on an iron plate coil base 118 fixed to the base frame 101.
6 and the electromagnetic coil 116 and the permanent magnet 1
15 is opposed via a slight gap. The permanent magnet 115 and the electromagnetic coil 116 constitute a first linear motor for driving the shuttle unit 110.

Each of the electromagnetic coils 116 is spirally wound to have a width twice as large as that of the permanent magnet 115. As shown in FIG. 10, six electromagnetic coils 116 are arranged in a row. FIG. 10 is a schematic diagram in which the outer edges of adjacent electromagnetic coils 116 are in contact with each other.

Of the six electromagnetic coils 116, the electromagnetic coils 116 at both ends are for reversing the operation of the first linear motor, and are connected in series to the same lead wire. The four middle electromagnetic coils 116 are for driving the first linear motor at a constant speed, and are connected in series two by two to a lead wire different from the above-mentioned lead wire.

In the first linear motor configured as described above, by energizing the electromagnetic coil 116 in the magnetic field of the permanent magnet 115, a thrust based on Fleming's left-hand rule is generated in the electromagnetic coil 116. .
However, since the electromagnetic coil 116 is fixed to the base frame 101 and does not move, the reaction force of the thrust acts on the permanent magnet 115 side, and as a result, the shuttle unit 1
10 moves while being guided by the first stay shaft 102.

The shuttle unit 110 can reciprocate at a high speed by controlling the current applied to the electromagnetic coil 116. Reference numeral 117 (see FIG. 5) denotes a transmission type position detection sensor provided between the shuttle frame 112 and the base frame 101 (the operation will be described later).

A second stay shaft 103 arranged in parallel with the first stay shaft 102 has a balance shuttle 122 formed similarly to the shuttle frame 112.
Are slidably fitted. A weight 121 is mounted on the balance shuttle 122, and a yoke 124 is mounted on a lower portion. On the lower surface of the yoke 124, permanent magnets 125 similar to the permanent magnets 115 arranged on the shuttle unit 110 are arranged. 123 is the first
Balance shuttle 12 with stay shaft 102
2 is a roller for supporting the roller.

Further, the balance shuttle 122 has a pair of arms 1 protruding on both sides of the base frame 101.
29 are connected. The tip of the arm 129 reaches the opposite side beyond the position of the shuttle unit 110, and the weight unit 130 is attached to the tip.

The balance shuttle 122 and the weight 121
, Yoke 124, permanent magnet 125, arm 129
And the weight unit 130 is the balance shuttle unit 1
20. This balance shuttle unit 120
Can move integrally with the shuttle unit 110 in parallel. Reference numeral 131 denotes a roller rotatably attached to the weight unit 130 so as to run on the base frame 101.

The balance shuttle unit 120 is formed so that the total weight thereof is substantially equal to the total weight of the shuttle unit 110.
The weight distribution is set such that the locus of the entire center of gravity of the unit when the unit moves is substantially the same as the locus of the center of gravity of the shuttle unit 110 when the unit moves.

Returning to FIGS. 4 to 6, the coil base 12
8, an electromagnetic coil 126 similar to the electromagnetic coil 116 is provided in parallel, and the electromagnetic coil 126 and the permanent magnet 125 are opposed to each other with a small gap. These permanent magnets 12
5 and the electromagnetic coil 126 constitute a second linear motor for driving the balance shuttle unit 120. The balance shuttle unit 120 can be reciprocated at a high speed by controlling the energization of the electromagnetic coil 126.

FIG. 11 is a schematic diagram of the circuit configuration for the first and second linear motors. The same drive current is supplied from one drive circuit 105 to each of the electromagnetic coils 116 and 126, whereby the shuttle unit 110 The balance shuttle unit 120 performs a high-speed reciprocating motion at the same speed in a relatively opposite direction. To this end, the polarity of the permanent magnets 115, 125 or the electromagnetic coils 116, 12
6 is reversed between the shuttle unit 110 and the balance shuttle unit 120.

A control unit 106 for controlling the operation of the drive circuit 105 receives detection signals for inversion and constant speed from the position detection sensor 117 on the shuttle unit 110 side, and performs reciprocation by feedback control. Control is performed. The runaway of the balance shuttle unit 120 and the like are monitored by a detection signal input to the control unit 106 from the position detection sensor 127 on the balance shuttle unit 120 side.

In the line printer having such a configuration, the shuttle unit 110 is connected to the first stay shaft 1.
02, the shuttle unit 1
A balance shuttle unit 120 having approximately the same weight as 10
The shuttle unit 110 is guided by the second stay shaft 103 and reciprocates at the same speed as the shuttle unit 110 in the opposite direction. Therefore, the shuttle unit 110
The reaction force generated on the base frame 101 with respect to the reciprocating motion of the balance shuttle unit 120 is offset by the reciprocating motion of the balance shuttle unit 120.

During the reciprocating movement, the track of the center of gravity of the balance shuttle unit 120 and the shuttle unit 11
Since the trajectories of the center of gravity of 0 substantially coincide with each other, no rotational moment is generated by the reciprocating motion of both shuttle units 110 and 120.

Printing by the line printer is performed by reciprocating the shuttle unit 110 and the balance shuttle unit 120 and operating a predetermined print element of the predetermined print head 80 at a predetermined time. At this time, the printing wire of the printing element protrudes in the direction of arrow A in FIG.
The printing paper conveyed in the direction of arrow B in the paper conveyance path 104 is hit via an ink ribbon (not shown), and printing is performed.

The balance shuttle unit 120
Connects the balance shuttle 122 and the weight unit 130 using a rope or a belt instead of the arm 129 so that the weight unit 130
It may be configured to move in the same direction and at the same speed.

Next, various application examples of the above-described line printer device (hereinafter, referred to as the above-described device) will be described. First application example: In the case of this application example, as shown in FIG.
Balance shuttle unit 132 with the unit removed
Are provided on both sides of the shuttle unit 110. 13
3 is a stay shaft. In this case, the total weight of the two balance shuttle units 132, 132 is substantially the same as the weight of the shuttle unit 110, and the travel line of the center of gravity of the two balance shuttle units 132, 132 is the travel line of the center of gravity of the shuttle unit 110. It is arranged so as to substantially match with.

Both balanced shuttle units 132, 13
2 are driven in the same direction and at the same speed. Note that three or more balance shuttle units 132 may be provided, or a plurality of balance shuttle units and a weight unit or the like connected by an arm or the like may be arranged in combination.

Second application example: In the case of this application example, FIG.
As shown in the figure, the balance shuttle unit 134 has an arm 129 and a weight unit 130 as compared with the above-described device.
Is not provided, and the balance shuttle unit 134
Is substantially the same as the weight of the shuttle unit 110. Therefore, a rotational moment is generated by the reciprocating motion of the shuttle unit 110 and the balance shuttle unit 134.

Therefore, in this application example, the motor 135 that generates a rotational torque in the opposite direction with substantially the same magnitude as the rotational moment generated by the movement of the shuttle units 110 and 134 is used as the motor 135 and the rotational moment generated by the shuttle units 110 and 134. It is mounted between the housing 136 and the base frame 101 with their central axes aligned.

With such a configuration, the rotational moment of both shuttle units 110 and 134 and the rotational torque of motor 135 are canceled out, and no rotational vibration is generated. Note that a rotary solenoid or the like may be used instead of the motor 135.

Third application example: In the case of this application example, FIG.
As shown in FIG.
The base frame 101 is provided in the same manner as the application example of
36 is provided rotatably coaxially with the rotational moment. A very heavy weight 137 having a moment of inertia equal to or greater than the rotational moment of the shuttle units 110 and 134 and having a center of gravity at the center axis position of the rotational moment is attached to the base frame 101. 138 is a bearing.

With this configuration, both shuttle units 110 and 1 with respect to the base frame 101 are arranged.
By suppressing the influence of the rotational moment caused by the rotational vibration 34, the generation of rotational vibration can be suppressed.

Fourth application example: In the case of this application example, FIG.
As shown in the figure, the weight 137 in the third application example is realized by a housing 139. Here, a fixed base 140 that rotatably supports the housing 139 is provided coaxially with the rotation centers of the shuttle units 110 and 134, and the rotational moment of the shuttle units 110 and 134 is canceled by the inertia moment of the housing 139. That is what it is.

Usually, the moment of inertia of case 139 is sufficiently larger than the rotational moment of both shuttle units 110 and 134, and the period of rotational vibration is fast, so that case 139 does not rotate.

Fifth application example: In the case of this application example, FIG.
As shown in the figure, the two anti-vibration rubbers 141a and 141b are installed at the connecting portion between the base frame 101 and the housing 136, and their viscosity absorbs the rotational motion and utilizes the fact that the cycle of the rotational vibration is fast. Unit 110, 134
Is not transmitted to the housing 136.

Next, various embodiments of the shuttle mechanism used in the line printer having the above configuration and operation will be described.

FIG. 1 shows a first embodiment.

In the case of the present embodiment, as shown in FIG. 1, the head frame 111a of the printing unit and the shuttle frame 112 of the shuttle unit constituting the shuttle mechanism 150 together with the printing unit are brought into close contact with the opposing surfaces, and Are connected by bolts or the like at the two connection points 151 and 152.

As a result, the shuttle unit and the printing unit are in close contact with each other, so that the number of bonding portions between the two heat sources of each unit increases. Accordingly, the temperature difference between the shuttle frame and the head frame, which has conventionally been a problem, is reduced, and the rigidity against heat is increased. As a result, it is possible to suppress the deformation of the shuttle frame and stabilize the print quality.

FIG. 2 shows a second embodiment.

In the shuttle mechanism 160 of the present embodiment, as shown in FIG.
61 also connects both frames 111a and 112.
Therefore, the degree of adhesion between both units is improved as compared with the case of the previous example,
A better effect can be obtained. In addition, it is more effective if the connecting portions are both ends and a plurality of portions between them.

FIG. 3 shows a third embodiment.

In the shuttle mechanism 170 of this embodiment, as shown in FIG. 3, the shuttle frame 11 of the first and second embodiments
2 (part below the dashed line) and the head frame 111
a (the portion above the one-dot chain line). In this case, there is no temperature difference between the two frames, and a more excellent effect can be obtained.

FIG. 17 shows an experimental result on the effect of the present invention. This experiment was performed on the shuttle mechanism of FIG. 1 of the first embodiment, and the amount of change in the head gap (vertical axis) due to temperature rise was examined for the print heads of each module No. shown on the horizontal axis. The amount of change is a value when the initial position is set to 0, and + indicates a large gap direction and-indicates a small gap direction. Each of the curve groups A, B, C, D, E, and F is a result under the following conditions. The solid line indicates the conventional structure, and the dotted line indicates the structure of the present invention.

The curve groups A, B and C are for the case where the coil temperature of the print head is 95 ° C. (print head heating). The curve group A is for the upper part of the head, the curve group B is for the wire guide portion of the head, A curve group C is a value measured at the lower portion of the head. Curve groups D, E, and F are for the case where the coil temperature of the print head is 102 ° C. and the temperature of the yoke below the shuttle frame is 60 ° C. (both the print head and the shuttle side are heated). In the lower part, the curve group E is the value measured in the wire guide portion, and the curve group F is the value measured in the upper part of the head.

From the results shown in this figure, it can be seen that in any case, the structure of the present invention has a smaller change in the printing gap (higher rigidity).

[0056]

As described above, according to the present invention, it is possible to suppress the deformation of the shuttle frame and the head frame due to the temperature rise during the operation of the shuttle mechanism, thereby realizing a stable printing quality.

[Brief description of the drawings]

FIG. 1 is a front view showing an outline of a main part of a shuttle mechanism according to a first embodiment of the present invention.

FIG. 2 is a front view showing an outline of a main part of a shuttle mechanism according to a second embodiment of the present invention.

FIG. 3 is a front view showing an outline of a main part of a shuttle mechanism according to a third embodiment of the present invention.

FIG. 4 is a perspective view of a line printer device to which the present invention is applied.

FIG. 5 is a plan view of a line printer device to which the present invention is applied.

FIG. 6 is a side sectional view of a line printer device to which the present invention is applied.

FIG. 7 is a side view showing a mounted state of the print head of FIG. 4;

FIG. 8 is a front view showing a mounted state of the print head of FIG. 4;

FIG. 9 is a plan view of a permanent magnet of the line printer device to which the present invention is applied.

FIG. 10 is a plan view of an electromagnetic coil of the line printer device to which the present invention is applied.

FIG. 11 is a schematic diagram of a circuit configuration of a line printer device to which the present invention is applied.

FIG. 12 shows a first example of the line printer device shown in FIGS.
It is a schematic diagram of an application example of.

FIG. 13 shows a second example of the line printer shown in FIGS.
It is a schematic diagram of an application example of.

FIG. 14 shows a third example of the line printer device shown in FIGS. 4 to 11;
It is a schematic diagram of an application example of.

FIG. 15 shows a fourth example of the line printer device shown in FIGS. 4 to 11;
It is a schematic diagram of an application example of.

FIG. 16 shows a fifth example of the line printer device shown in FIGS. 4 to 11;
It is a schematic diagram of an application example of.

FIG. 17 is an explanatory diagram of an effect of the present invention.

FIG. 18 is a front view showing an outline of a main part of a conventional shuttle mechanism.

FIG. 19 is a diagram illustrating the operation principle of a print head.

[Explanation of symbols]

 110 Shuttle Unit 111 Printing Unit 111a Head Frame 112 Shuttle Frame 150, 160, 170 Shuttle Mechanism 151, 152, 161 Joint Location 171 Integrated Frame

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 2/245 B41J 19/18

Claims (3)

(57) [Claims] A print head for performing printing, and a print head are supported.
A print unit having a head frame to hold the shuttle frame and a mechanism for reciprocating the print unit.
In the printing apparatus having a shuttle unit having the entire bottom surface of the head frame and said head frame
The Shah upper and said head frame is brought into close contact with the shuttle frame having an upper surface of larger area than the bottom surface
A printing apparatus , comprising: a head frame and two ends of a head frame . 2. A print head for printing, and a print head.
A print unit having a head frame to hold the shuttle frame and a mechanism for reciprocating the print unit.
In the printing apparatus having a shuttle unit having the entire bottom surface of the head frame and said head frame
The Shah upper and said head frame is brought into close contact with the shuttle frame having an upper surface of larger area than the bottom surface
Printing, characterized in that bound in two places between them in at least one location across the head frame and a torque frame
Equipment . 3. A print head for performing printing, and a print head.
A print unit having a head frame to hold the shuttle frame and a mechanism for reciprocating the print unit.
In the printing apparatus having a shuttle unit having, larger than the bottom surface of the head frame and the head frame
Integrated with the shuttle frame that has a large surface area
A printing device characterized by being formed .