JPH0472704B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an improvement of a printer, and mainly relates to a small printer that can print by manually moving the print head.

[Background of the invention]

In recent years, with the spread of personal computers, the demand for printers as output means has increased.
As is well known, conventional printers include a print head for printing on a printing target (usually paper, etc.) by means such as thermal, dot impact, electric discharge, or ink jet, and a stepping motor or the like for moving the print head. It consists of a print head drive system, a print object feed mechanism such as a paper feed mechanism for moving the print object, and a drive circuit to drive the print head drive system and print object feed mechanism, and in most cases, these are - It is housed in one box. Conventionally, in such a printer, a printing object feeding mechanism such as a paper feeding mechanism is large, so that the entire device is also large and has a complicated structure. In addition, the printing targets that can be used are limited to those with flexibility in the form of sheets or rolls, such as those that are bound like books, large papers other than the dimensions, thick papers, and boxes. The drawback was that it was difficult to print on three-dimensional objects such as walls and objects that could not be moved.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, to provide a small and lightweight printer that does not limit printing to sheets or rolls.

[Summary of the invention]

In order to achieve the above object, the present invention has as its constituent elements: (a) a casing as a base body; and (b) a casing that is rotatably supported with respect to the casing and that controls the relative position of the casing with respect to the printing target. (c) a position detection mechanism that is activated in response to the movement of the moving means and outputs a position signal indicating at least the position of the housing with respect to the printing target; (d) supported on the housing side. (e) one end is fixed to the housing and the other end is fixed to the print head; A parallel plate spring that moves the print head parallel to the housing;

In the above, the moving means moves the printing head relative to the printing object via the housing. The position detection mechanism detects the relative position of the housing to which the print head is attached with respect to the object to be printed.

[Embodiments of the invention]

The present invention will be explained below with reference to the drawings.

FIG. 1 is a schematic explanatory diagram of an embodiment of the present invention. In FIG. 1, 1 is a personal computer, 2 is a printer of the present invention, and 3 is a printing object (usually paper). Printer 2 manually prints target 3
be moved over. When the start switch above the printer 2 is pressed, the personal computer 1 transfers characters or graphic data to be printed to the printer 2. The printer 2 prints characters or graphic data on the printing object 3 as it moves.

FIG. 2 is a diagram showing the principle of printing. Here, an 8-dot inline head will be used as the print head. For example, when printing the katakana character "i", it is detected that the print head has reached the _x1 position, and the _P5 dot of the inline head is printed. Next, when the print head reaches position x ₂ , print P ₄ , and then print the filled-in dots in Figure 2 when it reaches x ₃ , x ₄ ... x ₇ , and you will get "I". ” can be printed. Printing methods using such in-line print heads are widely used in printers.

FIG. 3 is a sectional view of an embodiment of a printer according to the present invention. The printing method is based on the principle shown in FIG. In Fig. 3, 4 is a housing, 5 is a start switch, 6 is a cassette holder, 7 is a ribbon cassette, 8 is a print head, 9 and 13 are wheels as a means of movement, 10 is a pulley, and 11 is a position detection mechanism. Rotary encoder, 12 ink ribbon, 14 belt, 15 parallel plate spring, 1
6 is a cable, 17 is a winding shaft, and 18 is a hub.

FIG. 4 is a sectional view taken along line A-A' in FIG. 16
is a cable.

FIG. 5 further shows a sectional view taken along line B-B' of the printer of the present invention shown in FIG.

The structure will be explained with reference to FIGS. 3, 4, and 5. A start switch 5 is attached to the housing 4. Further, a cassette holder 6 is connected to the housing 4 via a parallel leaf spring 15. The print head 8 is fixed to the cassette holder 6,
The ribbon cassette 7 is removably attached to the cassette holder 6. An ink ribbon 12 is built into the ribbon cassette 7, and the ink ribbon 12 is wound around a hub 18. One hub is connected to a winding shaft 17.
is inserted into. The winding shaft 17 is driven by a wheel 13 rotatably supported by the housing 4 via a belt 14. The rotary encoder 11 is in contact with a wheel 9 connected to the housing 4 via a pulley 10. Start switch 5 and print head 8
is connected to the computer 1 via a cable 16.

Next, the operation will be explained. The method of detecting the position with respect to the printing object 3 is as follows: First, when the printer 2 is moved manually or the like, the relative position between the printer 2 and the printing object 3 changes, and the wheels 9 and 13 rotate.In particular, the rotation of the wheel 9 is controlled by the pulley. 19, the rotary encoder 11 is rotated, and as a result, the rotary encoder 11 outputs a position signal to the computer 1 via the cable 16, and the printer 2 and the printing target 3
The relative position is detected. The rotary encoder 11 is known to be an optical type or a magnetic type, and any type can be used as long as it outputs an output according to rotation.

The printing operation begins when print data is sent to the print head 8 via the cable 16.
Each dot generates heat according to the data. As a result, the ink ribbon 12 sandwiched between the printing head 8 and the printing object 3 is heated, and the ink is transferred to the printing object 3. This is a known technique as a thermal transfer method. The rotation of the wheel 13 causes the take-up shaft 17 to rotate via the belt 14, and the ink ribbon 1
2 is wound onto one side of the hub 18. Therefore, the unused ink ribbon 12 is always in contact with the printing head 8 and the printing object 3.

The cassette holder 6 and the printing head 8 are held in the housing 4 by a parallel plate spring 15, and the printing head 8 is attached to the printing object 3 by the biasing force of the parallel plate spring 15.
The structure is such that it imposes Print head 8
is moved parallel to the housing 4 by the action of the parallel leaf spring 15. That is, even if the print head 8 moves in and out of the housing 4, the attitude of the print head 8 with respect to the print object 3 remains unchanged and constant, so the contact between the print object 3 and the print head 8 is also constant. As a result, print quality is maintained. (If the posture or pressing force of the print head 8 with respect to the print object 3 changes, the contact state between the print head 8 and the print object 3 changes, causing variations in shading and deteriorating print quality.) Since the parallel plate spring 15 held parallel to the print head 15 does not expand or contract in the horizontal direction, there is no movement of the print head 8 in the horizontal direction with respect to the housing 4, and therefore the relative position of the print head 8 in the horizontal direction with respect to the housing 4 is always constant. As a result, the printing interval is kept constant.

The ribbon cassette 7 has a claw 29 attached to the cassette holder 6.
It is held in place and can be easily attached and detached.

Although the print head 8 has been described as using a thermal head, a wire dot type or other type can also be used.

FIG. 6 is a perspective view of the print head 8 of the printer of the present invention. Print head 8 is attached to head holder 30
and a head 33. The head holder 30 is
It consists of a mounting fixing hole 31 and a sliding surface 32. The head 33 is of a heat-sensitive type and consists of a printing dot part 34 and a lead part 35, and is embedded in the head holder 30. The sliding surface 32 has a cylindrical curved shape, and the printed dot portion 34 is located at the apex of the sliding surface 32.

7 and 8 show the state in which the printing head 8 and the printing object 3 are in contact with each other. FIG. 7 shows a case where the printing head 8 contacts the printing object 3 perpendicularly,
The printing dot portion 34 directly faces the printing target 3, and in this case, high quality printing is possible.

FIG. 8 shows a case where the printing head contacts the printing object 3 at a slight angle. As mentioned above, the printing head 8 always comes into contact with the printing object 3 at a constant angle due to the action of the parallel leaf spring 15. However, the relative inclination between the printing head 8 and the printing object 3 may change temporarily due to local unevenness of the printing object 3. Even in this case, the sliding surface 3
2 has a smoothly formed cylindrical curved surface shape, so that the printing dot portion 34 can reliably come into contact with the printing target 3.

FIG. 9 shows a conceptual diagram of a drive circuit for driving a printer according to the present invention. 1 is a personal computer, 19 is a microprocessor, 20 is a print head drive section, 21 is a print head, 22 is a position detection section, and 23 is a start switch.

The microprocessor 19 has ROM, RAM
is built in, and the ROM stores programs and data necessary for printing, such as data for converting received ASCII code into printing information as shown in FIG. Also
RAM is used as memory for executing instructions. Various known microprocessors can be used as the microprocessor 19.

〔Effect of the invention〕

The printing head is held so that it can move parallel to the housing with a parallel plate spring, and is biased against the printing object.The contact surface of the printing head with the printing object is made into a convex curved shape, and the printing dot part is placed at the apex of the contact surface. Since the printer is placed at Since there is constant contact, printing with less uneven printing density is possible.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of the system, FIG. 2 is a diagram of the printing principle, FIG. 3 is a sectional view of an embodiment of the printer according to the present invention, and FIG. 4 is a sectional view taken along line A-A' shown in FIG. 3.
5 is a sectional view taken along the line B-B' shown in FIG. 3, FIG. 6 is a perspective view of the print head of the printer of the present invention, FIGS. 7 and 8 are illustrations of the contact state of the print head, and FIG. 9
The figure is a block diagram of drive rotation. 2... Printer, 3... Printing target, 7... Ribbon cassette, 8... Printing head, 15... Parallel leaf spring, 30... Head holder, 32... Sliding surface,
33...Head, 34...Printing dot part.

Claims (1)

[Scope of Claims] 1. A housing as a base body, a print head that prints by contacting the print target, and a print head that is arranged between the print head and the housing and that attaches the print head to the print target. a moving means rotatably supported with respect to the casing and configured to move the position of the casing relative to the printing target; and activated in response to the movement of the moving means; a position detection mechanism that outputs a position signal corresponding to at least a position of the housing relative to the printing target, and the elastic body has one end fixed to the housing and the other end fixed to the printing head. a parallel plate spring that moves the printing head parallel to the housing, and the surface of the printing head that comes into contact with the printing object has a convex curved shape protruding toward the printing object. printer.