JP2714514B2 - Printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-end belt printer in which a paper clamper is provided between a pair of timing belts provided at both ends of a platen roller.

[0002]

2. Description of the Related Art FIG. 12 shows, for example, JP-A-63-30948.
FIG. 13 is a side view of a main part of a conventional thermal transfer printer of the double-end belt type disclosed in Japanese Patent Application Publication No. 2 (Kokai) No. 2 (KOKAI), and FIG. In the drawing, 1 is a platen roller, 2 is a pair of first toothed pulleys as platen toothed pulleys provided coaxially at both ends of the platen roller 1, and 3 is meshed with the first toothed pulley 2. The timing belt 3 travels at a speed substantially equal to the peripheral speed of the platen roller 1. Reference numerals 4 and 5 denote two pairs of toothed pulleys for extending and driving the timing belt 3, that is, a second pulley.
And a third toothed pulley.

Reference numeral 6 denotes a paper clamper provided between the timing belts 3, reference numeral 7 denotes a printing paper, reference numeral 8 denotes an ink sheet, and reference numeral 9 denotes a thermal head for thermally transferring the ink of the ink sheet 8 to the printing paper 7 by an electric signal.

In the conventional thermal transfer printer of the double-end belt type constructed as described above, the paper clamper 6 is at the paper feed position at the start of printing, and the leading end of the printing paper 7 is held by the paper clamper 6. The printing paper 7 is transported to the printing initial position by moving the paper clamper 6 by driving the timing belt 3. The thermal head 9 is separated from the platen roller 1 when the paper clamper 6 passes, and contacts the platen roller 1 after the paper clamper 6 passes. Thereafter, printing of the first color is started.

During printing, the paper clamper 6 is rotated by the timing belt 3 in the direction of arrow A in FIG. When printing of the first color is completed in this way,
The thermal head 9 is separated from the platen roller 1, and thereafter, the second color and the third color are similarly printed.

FIG. 14 shows an example of a conventional mechanism for attaching the paper clamper 6 to the timing belt 3 (Japanese Patent Application No. 33788/93).
FIG. 15 is a partial sectional view of FIG. In the figure, reference numeral 2a denotes a concave groove provided on the outer periphery of the first toothed pulley 2, and the concave groove 2a is provided over the entire circumference at the center in the thickness direction of the first toothed pulley 2. ing. Reference numeral 3a denotes a clamper mounting hole provided at a position facing the concave groove 2a of the timing belt 3. The paper clamper 6 is driven by a nut 11 with a clamper mounting member (screw) 10 penetrating the clamper mounting hole 3a. Belt 3
Attached to.

The concave groove 2a of the first toothed pulley 2 is provided in such a size as to avoid the head portion of the clamper mounting member 10, and there is no interference of the clamper mounting member 10 with the first toothed pulley 2. It has become. Of course, the second and third toothed pulleys 4 and 5 are also provided with the same grooves as the grooves 2a.

[0008]

In the conventional paper clamper mounting mechanism configured as described above, since the concave groove 2a is present, the timing belt 3 and the toothed pulley 2 are required to secure an effective engagement amount. Has a problem that the width of the timing belt 3 and the toothed pulleys 2, 4, and 5 must be increased. In addition, since there is a gap between the clamper mounting hole 3a and the clamper mounting member 10 although the dimensions are small, the positional relationship between the timing belt 3 and the paper clamper 6 is disturbed, and a color shift occurs. There were also points.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and the timing belt and the toothed pulley are reduced in width to reduce the overall size. It is an object of the present invention to obtain a printer that can prevent misalignment and improve printing position accuracy.

[0010]

According to a first aspect of the present invention, there is provided a printer in which holding portions forming a holding groove for holding a timing belt are provided at both ends of a paper clamper, and the outer periphery of each toothed pulley is provided. The parts are provided with recesses for avoiding the holding parts.

In the printer according to the second aspect of the present invention, the holding portions forming the holding grooves for holding the timing belt are provided at both ends of the paper clamper, and the holding portions are provided on the outer periphery of each toothed pulley. In addition to the provision of recesses for avoiding the above, the number of teeth of the timing belt is configured to be a positive multiple of the number of teeth of each toothed pulley.

In the printer according to the third aspect of the present invention, the holding portions forming the holding grooves for holding the timing belt are provided at both ends of the paper clamper, and the holding portions are provided on the outer periphery of each toothed pulley. Providing recesses for avoiding each other, and setting the holding position mark of the holding portion on the timing belt so that the timing belt is stretched in an appropriate state such that the holding portion engages with each recess when the timing belt rotates. In addition, the timing belt and each toothed pulley are provided with tensioning position marks corresponding to each other.

[0013]

According to the present invention, the holding portions provided at both ends of the paper clamper hold the timing belt, and the paper clamper is erected between the timing belts without any deviation in position. In addition, interference between the holding portion and each toothed pulley is avoided.

[0014]

【Example】

Embodiment 1 FIG. FIG. 1 is a perspective view showing a main part of a thermal transfer printer according to an embodiment of the present invention, FIG. 2 is an enlarged perspective view showing a part of FIG. 1, and FIG. 3 is an enlarged view of a first pulley of FIG. FIG. 4 is a perspective view of the attachment portion of the paper clamper to the timing belt of FIG. 3 as viewed from the outer peripheral side of the timing belt, and FIG. 5 is a perspective view of the timing belt of FIG. 4 as viewed from the inner peripheral side. 6, FIG. 6 is a side view of FIG. 3, and FIG. 7 is VII-VII of FIG.
FIG. 16 is a cross-sectional view taken along the line, and the same or corresponding parts as in FIGS. 12 to 15 are denoted by the same reference numerals and description thereof will be omitted.

In FIG. 1, reference numeral 2b denotes a recess (relief groove) provided so as to cut one tooth of the first toothed pulley 2 in a direction parallel to its axis. Reference numeral 6b denotes a holding groove provided at both ends of the paper clamper 6. A holding member (holding portion) 6c of the toothed pulley 2 forming the holding groove 6b is formed so as to wrap one tooth of the timing belt 3. I have. 6d is a saw tooth provided on the inner surface of the holding groove 6b.

Generally, the timing belt 3 is formed of a resilient material, and the timing belt 3 is pushed into the holding groove 6b to be inserted, so that the holding member 6c meshes with the teeth of the timing belt 3 and the paper clamper 6 and the timing belt 3 is held so that the positional relationship of 3 is not disturbed. The concave portion 2b is formed to have a size that allows the holding member 6c on the side to be engaged with the toothed pulley 2 to have a margin. The number of teeth of the timing belt 3 is configured to be an integral multiple of the number of teeth of the first toothed pulley 2 so that the engagement between the concave portion 2b and the holding member 6c due to the rotation of the first toothed pulley 2 matches. I have.

In the mounting mechanism of the paper clamper 6 configured as described above, one tooth portion of the timing belt 3 is inserted into the holding groove 6b from the side so as to mesh with the concave portion 2b of the first toothed pulley 2. The paper clamper 6 is joined to the timing belt 3. When the paper clamper 6 grips the leading end of the printing paper 7 and runs, the holding member 6c enters the concave portion 2b, so that interference between the holding member 6c and the first toothed pulley 2 does not occur, and the printing paper 7 is smoothly moved. You can run.

Embodiment 2 FIG. Next, FIG. 8 is a side view showing a main part of a thermal transfer printer according to an embodiment of the present invention. In the figure, 2 to 7, 9 are the same as those described in the first embodiment. 4b is one of the second toothed pulleys 4
The concave portion 5b is provided so as to cut teeth deeply in a direction parallel to the axis thereof, and the concave portion 5b is provided to cut one tooth of the third toothed pulley 5 deep in a direction parallel to the axis. These recesses 4b and 5b are provided with a holding member 6c similarly to the recess 2b.
Is formed in a size that can be easily accommodated.

When the timing belt 3 is stretched around the first toothed pulley 2, the second toothed pulley 4, and the third toothed pulley 5, and the timing belt 3 is moved, the first pulley 2 As described above, the holding member 6c is
No interference occurs because a concave portion 2b is provided at a position where it engages with the toothed pulley 2 to avoid the holding member 6c. Also, in the second and third toothed pulleys 4 and 5, interference does not occur by setting the concave portions 4b and 5b at the positions where the holding members 6c are engaged.

Here, the timing belt 3 is rotated,
In order for the printing paper 7 to travel smoothly, the holding member 6c and the recesses 2b, 4b, 5b must necessarily mesh with each other. For this purpose, the number of teeth of the timing belt 3 is N, the number of teeth of the first toothed pulley 2 is M1, the number of teeth of the second toothed pulley 4 is M2, and the number of teeth of the third toothed pulley 5 is If the number is M3, N / M1 = integer, N / M2 = integer, N / M3 =
Must be an integer relationship. As an example of this, N = 1
68, M1 = 24, M2 = 28, M3 = 42. With such a relationship, it is only necessary to provide the concave portions 2b, 4b, 5b one by one for each toothed pulley 2, 4, 5.

FIG. 9 is a side view showing a main part of a thermal transfer printer according to an embodiment of the third aspect of the present invention, and FIG.
FIG. 11 is an explanatory view showing a mark positional relationship of the timing belt of FIG.

In the figure, reference numeral 3a denotes a first mark provided as a holding position mark and a tensioning position mark provided on the timing belt 3, and the first mark 3a indicates a position to be held by the holding member 6c. The drawing also shows a position where the timing belt 3 is fitted to the concave portion 4b which is a stretched position mark of the second toothed pulley 4 when the timing belt 3 is stretched. Also,
The first mark 3a is a double line so as to be easily distinguished from other marks described later, and the center of the double line is a reference position as shown in FIG.

Reference numeral 3b denotes a second mark as a stretched position mark provided at a position L1 away from the first mark 3a of the timing belt 3, and this second mark 3b is At the time of extension, the position where the first toothed pulley 2 is aligned with the concave portion 2b which is the extension position mark is shown.

Reference numeral 5c denotes a pulley-side mark provided as an extension position mark provided on the third toothed pulley 5, and this pulley-side mark 5c is provided on both sides of the concave portion 5b at the same angular interval from the concave portion 5b. They are provided one by one. Reference numeral 3c denotes a third mark as an extension position mark provided at a position L2 away from the first mark 3a of the timing belt 3, and this third mark 3c is used when the timing belt 3 is extended. , The position to be aligned with the pulley side mark 5c. An arrow mark 3d indicates the traveling direction of the timing belt 3 during use.

In order for the holding member 6c to escape by the recesses 2b, 4b, 5b as described above, even when the timing belt 3 circulates, the holding member 6c is kept in the respective recesses 2b, 4b, 5b.
It is necessary to engage the timing belt 3 in such an appropriate state.
Must be performed by trial and error while making a round, which is very troublesome.

However, in the third embodiment, the first to third marks 3a, 3b, 3c and the arrow mark 3d are provided on the timing belt 3, so that the arrow mark 3d is directed in the traveling direction of the timing belt 3. Then, the first to third marks 3a, 3b, 3c are respectively
b, the timing belt 3 can be easily stretched in an appropriate positional relationship only by adjusting to the pulley side mark 5c. The paper clamper 6 may be attached in accordance with the first mark 3a, which may be before or after the timing belt 3 is stretched. Further, since there are two pulley side marks 5c, it may be determined that the concave portion 5b is stretched with the concave portion 5b facing the first toothed pulley 2 as shown in FIG. 9, for example.

In the third embodiment, two pulley-side marks 5c are provided on the third toothed pulley 5, so that a plastic molded product is used as the third toothed pulley 5, for example, in the case of a paper transport path. Since the same third toothed pulley 5 can be used on both sides, the same mold can be used and assembly is simple.

In the third embodiment, the recesses 2b and 4b also serve as tension position marks on the toothed pulley, but a mark such as the pulley mark 5c may be provided separately. Conversely, depending on the number of teeth of the timing belt 3 and the number of teeth of each of the toothed pulleys 2, 4, and 5, all of the recesses 2b and 4
b and 5b may be used as the extension position marks. In the third embodiment, the first mark 3a serves both as the holding position mark and the extension position mark, but may be provided separately.

Further, in each of the above embodiments, the case where three toothed pulleys 2, 4, and 5 are used is shown, but four or more pulleys may be used. Further, in each of the above embodiments, the thermal transfer printer is shown. However, the present invention can be applied to other types of printers as long as they can transport paper in the same manner.

[0030]

As described above, in the printer according to the first aspect of the present invention, the holding portions forming the holding grooves for holding the timing belt are provided at both ends of the paper clamper. Since the outer peripheral portion is provided with a concave portion for avoiding the holding portion, the width of the timing belt and the toothed pulley is reduced to reduce the size of the entirety, and the positional displacement of the paper clamper with respect to the timing belt is prevented. This has the effect of improving the printing position accuracy.

In the printer according to the second aspect of the present invention, the number of teeth of the timing belt is configured to be a positive multiple of the number of teeth of each of the toothed pulleys. By providing only one concave portion in the toothed pulley, the holding portion can be engaged with each concave portion, and the paper clamper can be smoothly run with a simple configuration.

Further, in the printer according to the third aspect of the present invention, the timing belt is provided with the holding position mark of the holding portion, and the timing belt and each toothed pulley are provided with the corresponding tensioning position marks. In addition to the effects of the first aspect of the present invention, the work of stretching the timing belt can be simplified, and the mounting accuracy of the paper clamper can be improved, whereby the assembling time can be shortened and the maintainability can be improved. It has effects such as being able to be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of a thermal transfer printer according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view showing a part of FIG. 1;

FIG. 3 is an enlarged perspective view showing a first pulley of FIG. 2;

FIG. 4 is a perspective view of an attachment portion of the paper clamper of FIG. 3 to the timing belt as viewed from an outer peripheral side of the timing belt.

FIG. 5 is a perspective view of the timing belt of FIG. 4 as viewed from the inner peripheral side.

FIG. 6 is a side view of FIG. 3;

FIG. 7 is a sectional view taken along the line VII-VII in FIG. 6;

FIG. 8 is a side view showing a main part of a thermal transfer printer according to an embodiment of the present invention.

FIG. 9 is a side view showing a main part of a thermal transfer printer according to one embodiment of the third invention.

FIG. 10 is a perspective view showing the timing belt of FIG. 9;

FIG. 11 is an explanatory diagram showing a mark positional relationship of the timing belt of FIG. 9;

FIG. 12 is a side view showing a main part of an example of a conventional thermal transfer printer of a double-end belt type.

FIG. 13 is a plan view of FIG. 11;

FIG. 14 is a side view showing an example of a conventional mechanism for mounting a paper clamper on a timing belt.

FIG. 15 is a partial sectional view of FIG.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 platen roller 2 first toothed pulley (platen part toothed pulley) 2 b concave portion (tension position mark) 3 timing belt 3 a first mark (nipping position mark and tension position mark) 3 b second mark (tension) Setting position mark) 3c third mark (extension position mark) 4 second toothed pulley 4b recess (extension position mark) 5 third toothed pulley 5b recess 5c pulley side mark (extension position mark) 6 Paper clamper 6b Holding groove 6c Holding member (holding portion) 7 Printing paper 8 Ink sheet

Claims (3)

(57) [Claims] 1. A platen roller for bringing printing paper into close contact with an ink sheet, a pair of toothed pulleys provided on both ends of the platen roller, and the platen toothed pulley runs. A pair of toothed timing belts, a plurality of pairs of toothed pulleys for tensioning the timing belt, and a pair of holding portions forming a holding groove for holding the timing belt at both ends; A paper clamper is attached between the belts in parallel with the platen roller, and holds a leading end of the printing paper to pull and run the printing paper.
A thermal transfer printer, wherein concave portions for avoiding the holding portion are provided on the outer peripheral portion of each toothed pulley. 2. A platen roller for bringing printing paper and an ink sheet into close contact with each other, a pair of platen toothed pulleys provided at both ends of the platen roller, and the platen roller is stretched and run on the toothed pulley. A pair of toothed timing belts, a plurality of pairs of toothed pulleys for tensioning the timing belt, and a pair of holding portions forming a holding groove for holding the timing belt at both ends; A paper clamper is attached between the belts in parallel with the platen roller, and holds a leading end of the printing paper to pull and run the printing paper.
The outer periphery of each toothed pulley is provided with a recess for avoiding the holding portion, and the number of teeth of the timing belt is configured to be a positive multiple of the number of teeth of each of the toothed pulleys. Printer. 3. A platen roller for bringing the printing paper and the ink sheet into close contact with each other, a pair of platen toothed pulleys provided at both ends of the platen roller, and the platen toothed pulley travels. A pair of toothed timing belts, a plurality of pairs of toothed pulleys for tensioning the timing belt, and a pair of holding portions forming a holding groove for holding the timing belt at both ends; A paper clamper is attached between the belts in parallel with the platen roller, and holds a leading end of the printing paper to pull and run the printing paper.
A concave portion is provided on an outer peripheral portion of each of the toothed pulleys to avoid the holding portion, and the timing is adjusted in an appropriate state such that the holding portion meshes with the concave portion when the timing belt rotates. As the belt is stretched, a clamping position mark of the clamping portion is provided on the timing belt, and a tensioning position mark corresponding to the timing belt and each of the toothed pulleys is provided. A printer.