JPH03193478A - Printer - Google Patents

Abstract

PURPOSE:To rapidly and easily adjust a gap and to achieve wt. reduction without increasing the number of parts by forming a plurality of the engaging surfaces mutually different in the distance from the axis of other guide shaft and selectively engaged with the engaging part of a carrier to a gap adjusting member. CONSTITUTION:Gap adjusting members 31 are constituted of flange parts 33A, 33B integrally formed to both end surfaces of a body part 32 and holding the engaging part 24 of a carrier 21 from both sides thereof and the outer peripheral surface of the body part 32 is formed into an equilateral polygonal cross-sectional shape having engaging surfaces 34 respectively different in the distance from the axis of a guide shaft 12 and selectively and elastically engaged with the engaging part 24 of the carrier 21. Not only handle 35 but also a setting indication part 36 are provided to one flange part 33A. When the gap adjusting members 31 are rotated until the figure of the setting indicating part 36 coinciding with a reference line 37 corresponds to the thickness of paper to be used, the gap between a rubber belt 2 and a printing head 23 is automatically adjusted to the stage corresponding to the figure of the setting indication part 36.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printer. In particular, the present invention relates to a printer equipped with a gear adjustment mechanism that adjusts the gap between the platen and the print head.

[Prior Art] In a printer that inserts paper between a platen and a print head and uses the print head to print on the paper, the gap between the platen and the print head must be adjusted in consideration of the thickness of the paper to be inserted. A gap adjustment mechanism is provided to adjust the gap.

For example, in a supplementary printer in which a carrier having a print head is reciprocated in a direction parallel to the platen via a pair of kite shafts, a gap adjustment mechanism is provided between one of the guide shafts and the carrier; Alternatively, it is known that a gap adjustment mechanism is provided in a frame that supports both ends of one of the guide shafts.

In the former gap adjustment mechanism, a steel core collar is rotatably provided on one kite shaft and reciprocally movable in the axial direction of one of the guide shafts, and one end is rotatably supported on the other kite shaft. The other end of the carrier is engaged with the outer peripheral surface of the eccentric collar. Therefore, when the faith collar is rotated relative to one guide shaft, the carrier is rotated about the other kite shaft due to the eccentric action of the eccentric collar, making it possible to adjust the gap between the platen and the print head. can.

In the latter gap adjustment mechanism, a steel-core bushing is rotatably provided on a frame that supports both ends of one guide shaft, and the end of one guide shaft is inserted into an eccentric hole formed at an eccentric position of this eccentric bushing. Therefore, when the eccentric bushing is rotated, one guide shaft is displaced in the vertical direction due to the eccentric action of the steel core bushing, and as a result, the carrier uses the other guide shaft as a fulcrum. Because of the rotational displacement, the gap between the platen and the print head can be adjusted.

[Problems to be Solved by the Invention] However, although the above-mentioned double gap adjustment MTS can adjust the gap between the platen and the print head to any desired level by rotating the eccentric collar or bushing, In order to adjust the gap accordingly, it is necessary to slightly adjust the rotation of the eccentric collar or bushing, and then actually rotate the eccentric collar or bushing and check the gap using a gauge, etc. Since there is only one available, there is a problem that adjustment is troublesome and time consuming.

Moreover, with any gap adjustment mechanism, if the printing operation is started after adjusting the gap by rotating the faith collar or faith bushing, eccentricity may occur due to impact when the carrier moves back and forth or stops, or when the print head prints. There is a problem in that the collar and bushings rotate and the gap changes.

In order to solve this problem, a separate positioning mechanism can be provided to position the eccentric collar or bushing after rotation, but this would not only increase the number of parts, but also It goes against the demands of the government.

It is therefore an object of the present invention to solve these conventional problems, to be able to quickly and easily perform gap adjustment, and to be able to adjust the gap after adjustment without increasing the number of parts and without going against the demands for smaller size and lighter weight. An object of the present invention is to provide a printer that can maintain the gap accurately.

[Means for Solving the Problem] The invention described in claim 1 includes a pair of guide shafts that are provided parallel to the platen and spaced apart from each other by a predetermined distance, and one end of which is rotatable. a carrier that is movable and reciprocally movable in the axial direction of its guide shaft, has a print head on a surface facing the platen, and has an engaging portion at the other end; and is engaged with the engaging portion of the carrier. and a gap adjustment member rotatably provided on the other guide shaft and reciprocally movable in the axial direction of the guide shaft as the carrier reciprocates, The carrier is characterized in that a plurality of engagement surfaces are formed at different distances from the axis of the guide shaft and selectively engage with the engagement portion of the carrier.

Further, in the invention set forth in claim 2, in the invention set forth in claim 1, the gap adjustment member is set at a position that is visible from the outside by an engagement surface that engages with the engagement portion of the carrier. The present invention is characterized in that a setting instruction section is provided to indicate a setting step of the platen and print head.

Further, the invention as set forth in claim 3 is characterized in that, in the invention as set forth in claim 1, the gap adjusting member is provided with a handle for rotating the gear knob 11 adjusting member with respect to the guide shaft. do.

[Function] In the invention described in claim 1, in order to adjust the gap between the platen and the print head, the gap adjustment member is rotated with respect to the other guide shaft, and one of the engaging surfaces is rotated. Engage with the engaging portion of the carrier. Then, these engagement surfaces are from the axis of the other kite shaft! ? Since [ are different, the carrier is rotated using one of the guide shafts as a fulcrum. As a result, the gap between the platen and the printhead is changed in stages.

Therefore, simply by engaging the engagement surface according to the thickness of the paper being used with the engagement portion of the carrier, the gap will be automatically adjusted according to the engagement surface, allowing for quick gap adjustment. be able to. Moreover, since the engaging portion of the carrier and the engaging surface of the gap adjusting member are engaged, the gap adjusting member will not rotate due to impact, etc. Therefore, the positioning mechanism for positioning the gap adjusting member can be specially designed. Since there is no need to provide a gap in the gap after adjustment, the gap after adjustment can be maintained accurately without increasing the number of parts and without going against the demands for smaller size and lighter weight.

Further, in the invention described in claim 2, when the gap adjustment member is rotated with respect to the other guide shaft and one of the engagement surfaces is engaged with the engagement portion of the carrier, the setting instruction portion of the carrier is rotated. Since the setting stage of the gap between the platen and the print head, which is set by the engagement surface that engages with the engagement portion, can be confirmed, the gap adjustment can be performed quickly and easily.

Further, in the invention as set forth in claim 3, since the gap adjustment member can be rotated with respect to the other guide shaft by rotating the handle, the gap adjustment can be performed quickly and easily.

[Example] Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows the main parts of the printer of this embodiment. In the same figure, 1 is a stamp stand, 2 is a band-shaped rubber belt provided so as to enclose the stamp stand 1, and these constitute a platen. 3 is a carrier frame provided above it. The carrier frame 3 includes side frames 3A and 3B on both sides, and side frames 3A and 3 on both sides.
It is composed of a connecting frame 3C that connects the parts B to each other.

Between the side frames 3A and 3B, a lead screw 11 which also serves as a guide shaft is rotatably supported parallel to the marking stand 1, and a round shaft is provided at a position spaced apart from the lead screw 11 by a predetermined distance. A shaped guide shaft 12 is supported substantially parallel to the marking stand 1. That is, a lead screw 11 and a guide shaft 12, which also serve as guide shafts, are supported parallel to the marking stand 1 and spaced apart from each other by a predetermined distance.

The lead screw 11 has a male thread 13 on its outer peripheral surface.
A timing gear 15 for transmitting power from a motor (not shown) to the lead screw 11 via a timing belt 14 is attached to one end. One end of a carrier 21 is attached to the male screw 13 via a nut member 22. The nut member 22 is held at one end of the carrier 21 and has a female thread on its inner peripheral surface that engages with the male thread 13 of the lead screw 11 . Therefore, the carrier 21
The other end can be rotated using the lead screw 11 as a fulcrum, and is reciprocated in the axial direction of the lead screw 11 by the rotational drive of the lead screw 11.

A print head 23 is attached to the carrier 21 at a substantially intermediate position on the surface facing the marking stand 1, that is, the bottom surface, and fl! ! An engaging portion 24 is formed at the end opposite to the end supported by the lead screw 11. As shown in FIG. 2, the engaging portion 24 includes a pair of vertically opposed engaging pieces 25 and 26 formed to be elastically deformable in the vertical direction, and is rotatably attached to the kite shaft 12 and attached to the carrier 21. It is supported by the kite shaft 12 via a gap adjustment member 31 that is provided so as to be able to reciprocate in the axial direction of the kite shaft 12 as it reciprocates.

As shown in FIGS. 2 and 3, the kip adjustment member 31 includes a body portion 32 and a collar portion that is integrally formed on both end surfaces of the body portion 32 and sandwiches the engaging portion 24 of the carrier 21 from both sides. It is composed of 33A and 33B. Body part 3
The outer circumferential surfaces of the two outer peripheral surfaces have different distances from the axis of the guide shaft 12 and are different from each other in the engaging portion 24 of the carrier 21.
The cross section including a plurality of engaging surfaces 34 that selectively and elastically engage with the holder is formed into a regular polygon, here a regular dodecagon. Therefore, when the gap adjustment member 31 rotates relative to the kite shaft 12, each engagement surface 34 engages the engagement piece 2 of the engagement portion 24.
5 and 26 are engaged in sequence while being rotated with moderation.

A handle 35 for rotating the gap adjustment member 31 relative to the guide shaft 12 is provided on the outer end surface of the one flange portion 33A, and the handle 35 corresponds to each of the engagement surfaces 34 on the outer peripheral surface. A setting instruction section 36 is provided at the position. The setting instruction section 36 indicates the step of setting the gap set by the engaging surface 34 engaged with the engaging portion 24 of the carrier 21, and sets the step of setting the gap according to the thickness of the paper to be used. It is indicated by numbers such as 2.3... Correspondingly, the engagement surface 3 on the top side
4 and the corresponding number in the setting instruction section 36,
A reference line 37 is provided on the upper surface of the engaging portion 24 of the carrier 21. In other words, the setting instruction section 3 that matches the reference line 37
The number 6 indicates the current gap setting stage, which is visible from above.

Further, both ends of the guide shaft 12 are connected to the side frames 3A and 3 via eccentric bushings 41A and 41B.
Each is supported by B. Each eccentric bush 41A,
41B, as shown in FIGS. 4 to 6, a fitting cylindrical portion 42 rotatably inserted into the holding hole 4 formed in the side frames 3A, 3B, and an outer portion of the fitting cylindrical portion 42. two upper and lower flange portions 43 and 44 integrally provided on the end surface;
A knob 45 is provided integrally on the outer end surface of the flange portions 43 and 44.

The fitting cylinder part 42 has a support hole 46 that rotatably supports the end of the kite shaft 12 at an eccentric position on the inner end surface thereof, that is, at a position eccentric to the rotation axis of the fitting cylinder part 42.
are formed, and convex portions 47 and 48 are integrally provided at 180 degree intervals on the outer peripheral surface to elastically sandwich the side frames 3A and 3B between the flange portions 43 and 44. .

Among the two upper and lower flange portions 43 and 44, one of the flange portions 43 has a plurality of engagement members having a triangular cross section along the circumference centered on the rotation axis of the fitting cylinder portion 42. Matching teeth 49 are formed radially at constant pitch intervals.

Then, after the eccentric bushings 41A, 41B are inserted into the holding hole 4 from the state shown in FIG. In the moved state, each side frame 3A, 3B has an eccentric bushing 4.
A triangular protrusion 6 that elastically engages and disengages from the engagement teeth 49 as the members 1A and 41B rotate is bent into a V-shape by pressing or the like. In FIG. 4, 5 indicates a convex portion 47 when inserting each eccentric bush 41A, 41B into the holding hole
．． This is a through hole for inserting 48.

Next, the operation of this embodiment will be explained. 6 First, the parallelism between the printing stand 1 and the printing head 23 is checked. This is done by rotating each eccentric bushing 41A, 41B. When the knobs 45 of the eccentric bushes 41A, 41B are grasped and the knobs 45 are rotated, the engaging teeth 49 are set to 1.
The eccentric bushing 41A engages and disengages from the protrusion 6 one by one.
, 41B are rotated. In other words, eccentric bushing 41A,
41B is rotated by one tooth pitch of the engaging teeth 49 with moderation.

Then, as the eccentric bushes 41A and 41B rotate,
Since the support hole 46 is displaced in the vertical direction, the support hole 46
The end of the guide shaft 12 supported by the guide shaft 12 is displaced in the vertical direction.

Therefore, the eccentric bushes 41A and 41B on both sides are connected to the engaging teeth 4.
Adjustment is made so that the gap between the printing stand 1 and the printing head 23 is constant at each point within the reciprocating movement area of the carrier 21 while rotating the two 1tk pitches at a time. Since the engaging teeth 49 engage with the protrusions 6 of the side frames 3A and 3B, eccentric push and L due to impact after adjustment are prevented.
Rotation of 41A and 41B can be prevented. In other words, the parallelism after adjustment can be maintained.

Next, after adjusting the parallelism between the printing stand 1 and the printing head 23, the gap between the rubber belt 2 and the printing head 23 is adjusted. This includes the handle 3 of the gap adjustment member 31.
5 and rotate the handle 35 to rotate the gap adjustment member 31 with respect to the guide shaft 12. Then, each engagement surface 34 of the gap adjustment member 31 is sequentially engaged between the engagement pieces 25 and 26 of the carrier 21 while elastically deforming the engagement pieces 25 and 26 in the vertical direction. In other words, the engagement surface 34 of the gap adjustment member 31 is rotated with moderation and is sequentially engaged between the engagement pieces 25 and 26.

Then, since each engagement surface 34 has a different distance from the axis of the guide shaft 12, the other end of the carrier 21 is displaced stepwise in the vertical direction using the lead screw 11 as a fulcrum. When the carrier 21 is displaced in the vertical direction, the print head 23 is displaced in a stepwise manner in the vertical direction with respect to the rubber belt 2, so that the gap between the rubber belt 2 and the print head 23 is changed in steps. At this time, the gap setting stage can be confirmed by the number on the setting instruction section 36 that corresponds to the reference line 37.

Therefore, when the gap adjustment member 31 is rotated until the number on the setting instruction section 36 that corresponds to the reference line 37 corresponds to the thickness of the paper to be used, the gap between the rubber belt 2 and the print head 23 will be adjusted to the setting instruction section. It is automatically adjusted to the stage corresponding to the number 36. In this state, one of the engagement surfaces 34 of the gap adjustment member 31 is engaged while being held between the engagement pieces 25 and 26 of the carrier 21.
Rotation of the gap adjustment member 31 due to impact after adjustment can be prevented. In other words, the gap after adjustment can be maintained.

In this way, after adjusting the parallelism between the printing table 1 and the print head 23 and the gap between the rubber belt 2 and the print head 23, printing is performed. supply between. Subsequently, the carrier 21 is reciprocated along the guide shaft 12 by rotation of the lead screw 11, and the print head 23 is operated for printing. As a result, printing is performed on the paper.

Therefore, according to this embodiment, one end of the carrier 21 is screwed onto the lead screw 11 via the nut member 22, and the guide shaft 12 has a plurality of engagement surfaces having different distances from the axis of the guide shaft 12. A gap adjustment member 31 having a diameter of 34 is provided rotatably and reciprocally movable in the axial direction, and an engagement portion 24 formed at the other end of the carrier 21 is engaged with an engagement surface 34 of the gap adjustment member 31. Therefore, by rotating the gap adjustment member 31, the engaging portion 34 is adjusted to the carrier 21 according to the thickness of the paper to be used.
When elastically engaged with the engaging portion 24 of the
Since the gap can be automatically adjusted to match the gap, the gap can be adjusted quickly.

Furthermore, when the gap adjustment member 31 is rotated, each engagement surface 34 engages between the pair of engagement pieces 25 and 26 of the engagement portion 24 while elastically deforming the pair of engagement pieces 25 and 26 in the vertical direction. As the gap adjustment member 31 is adjusted to each engagement surface 34,
It can be rotated with moderation.

Moreover, when any of the engaging surfaces 34 is engaged with the engaging portion 24, the engaging surfaces 34 are elastically sandwiched between the pair of engaging pieces 25 and 26. , rotation of the gap adjustment member 31 due to impact or the like can be prevented. Since there is no need to provide a special positioning mechanism for positioning the gap adjustment member 31, the gap after adjustment can be maintained accurately without increasing the number of parts and without going against the demands for compactness and weight reduction. I can do it.

In addition, a handle 3 is attached to the flange 33A of the gap adjustment member 31.
5, the gap adjustment member 31 is light relative to the kite shaft 12 even when rotating with moderation relative to the engagement portion 34 of the gap adjustment member 31 or the engagement pieces 25 and 26 of the engagement portion 24. It can be rotated with force and smoothly. Therefore, the gap can be easily adjusted.

Moreover, when one of the engaging surfaces 34 engages between the engaging portions 24 of the carrier 21 due to the rotation, the setting stage of the gap set by the engaging surface 34 is set by the reference line 3.
Since you can check from the number in the setting instruction section 36 that matches 7, you can check the setting instruction section 3 according to the thickness of the paper used.
By rotating the gap adjustment member 31 until the number 6 coincides with the reference line 37, the gap setting stage corresponding to the number on the setting instruction section 36 can be automatically adjusted. Therefore, also from this point of view, the gap can be easily adjusted.

In addition, eccentric bushings 41A are attached to the side frames 3A and 3B.
, 41B are rotatably provided, and each eccentric bushing 41A
, 41B is provided with a support hole 46 that rotatably supports the end of the guide shaft 12, and the side frame 3A, Since a plurality of engagement teeth 49 that elastically engage and disengage from the protrusion 6 formed on the protrusion 3B are formed, the eccentric bushings 41A and 41B on both sides are rotated by one tooth pitch of the engagement teeth 49 to connect the printing base 1 and the print head. 23 can be adjusted. That is, since the eccentric bushings 41A and 41B can be rotated by one tooth pitch of the engagement teeth 49, the parallelism can be adjusted quickly and easily.

Moreover, any one of the engaging teeth 49 is connected to the frame 3A.

Since the bushings 3B are engaged with the protrusions 6, it is possible to prevent the eccentric bushings 41A and 41B from rotating due to impact or the like. This means eccentric bushing 41A.

Since there is no need to provide a special positioning tR mechanism for positioning 41B, the parallelism after adjustment can be adjusted to
It can be maintained reliably.

[Effects of the Invention] As described above, according to the present invention, the following effects can be achieved.

According to the invention set forth in claim 1, by rotating the gap adjustment member to engage the engaging portion according to the thickness of the paper used, etc., with the engaging portion of the carrier, the engaging portion can be adjusted according to the engaging surface. Since the gap is automatically adjusted to the specified gap, the gap can be adjusted quickly.

Moreover, since the engaging portions are engaged with each other, it is possible to prevent the gap adjusting member from rotating due to impact or the like. Therefore, there is no need to provide a special positioning mechanism for positioning the gap adjustment member, so the gap after adjustment can be maintained accurately without increasing the number of parts and without going against the demands of smaller size and weight reduction. can be done.

Further, according to the invention described in claim 2, when the gap adjustment member is rotated with respect to the other guide shaft and one of the engagement surfaces is engaged with the engagement portion of the carrier, the setting instruction is Since it is possible to check the setting stage of the gap between the platen and the print head, which is set by the engagement surface that engages with the engagement portion of the carrier, the gap adjustment can be performed quickly and easily.

Further, according to the invention as set forth in claim 3, when rotating the gap adjusting member relative to the other guide shaft, the gap adjustment can be performed quickly and easily since it can be done by rotating the handle. can.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which Fig. 1 is a perspective view showing the main parts, Fig. 2 is an exploded perspective view showing the relationship between the engaging part of the carrier and the gap adjustment member, and Fig. 3 is an exploded perspective view showing the relationship between the engaging part of the carrier and the gap adjustment member. ■−■ in Figure 2
4 is an exploded perspective view showing the attachment of the eccentric bushing to the kite shaft, FIG. 5 is a rear view of the eccentric bushing seen from direction V in FIG. 4, and FIG. 6 is the It is a side view of the devotional bush seen from the direction. 1.2... Stamp stand and rubber belt (platen), 11
...Lead screw (guide shaft), 12...
Kite shaft, 21...Carrier, 23...Print head, 24...Engagement portion, 31...Gap adjustment member, 34...Engagement portion. 35... Handle, 36... Setting instruction section. 4th diagram diagram

Claims (3)

[Claims] (1) A pair of guide shafts are provided parallel to the platen and spaced apart from each other by a predetermined distance, and one end of the guide shaft is provided to be rotatable and reciprocating in the axial direction of the guide shaft. a carrier having a print head on a surface facing the platen and having an engaging portion at the other end; and a carrier that engages with the engaging portion of the carrier and is rotatably connected to the other guide shaft, and reciprocates the carrier. a gap adjustment member provided so as to be able to reciprocate in the axial direction of the guide shaft, and the gap adjustment member is provided with a gap adjustment member whose distances from the axis of the other guide shaft are different from each other and which are engaged with the carrier. A printer characterized in that a plurality of engagement surfaces are formed to selectively engage with a joint portion. (2) A setting instruction section is provided at a position visible from the outside of the gap adjustment member to indicate the setting stage of the platen and print head set by the engagement surface that engages with the engagement section of the carrier. The printer according to claim 1, characterized in that: (3) The printer according to claim 1, wherein the gap adjustment member is provided with a handle for rotating the gap adjustment member with respect to the guide shaft.