JPH05124292A - Scanner for printer - Google Patents

Abstract

(57) [Abstract] [Purpose] In a printer scanning device in which the carriage is guided by a part of the printer base frame, the upper and lower protrusions of the carriage that holds the printer base frame are displaced in the carriage movement direction, and then disassembled and assembled. In addition to facilitating scanning, the weight reduction and reliability improvement of the scanning device are realized. [Structure] A printer base frame, a recording head, and a carriage on which this head is mounted are provided. A part of the printer base frame guides the carriage when it moves for recording, and two guide parts project from the carriage. The above protrusion is performed by sandwiching a part of the base frame, and the protrusion is sandwiched between the area where the protrusion on one side is formed and the area where the protrusion on the other side is formed. It is characterized in that there are no overlapping portions that are offset in the moving direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning device for a printer.

[0002]

2. Description of the Related Art A conventional scanning device for a printer is disclosed in Japanese Patent Application Laid-Open No.
As shown in -254733, the carriage 7 is positioned and guided by the two guide shafts 4, or the carrier 20 on which the printer head 10 is mounted, such as the actual flat plane 1-80427, is provided with one carrier shaft 4 and the end portion of the printer base frame. In most of the cases, the protrusion 9 protruding from the carrier 20 is vertically sandwiched to guide the positioning.

[0003]

However, in the structure of the above-mentioned Japanese Patent Laid-Open No. 1-253473, parts for fixing the two guide shafts to the left and right base frames are required, and moreover, respectively. Adjustment is required to keep the prints parallel to the print area. Therefore, there is a guide shaft that has good roundness and rigidity that does not deform due to printing force.
A book is also required, and many fixing parts and adjustment processes are required to adjust the parallelism, so it is vulnerable to environmental changes such as temperature change, vibration, shock, etc., and it becomes a costly and expensive product. .. In addition, the weight of the printer shaft increases the weight of the printer body, resulting in a product with poor portability, and the installation location is limited to a solid footing. In other words, the printer is large and heavy, and is vulnerable to environmental changes, and is expensive.

In a structure such as the actual open flat 1-80427, the projection 25 is formed when a carrier and a carrier shaft are sub-assembled into a printer base frame, although the drawbacks of Japanese Patent Laid-Open No. 1-253473 are reduced. Has a fatal drawback that the protrusion 25 is destroyed by twisting the end portion 9 of the printer base frame. Moreover, this can also occur when disassembling in after-sales service, resulting in wasted service costs and repair time for the consumer.

Therefore, the present invention solves such a problem, and an object of the present invention is to provide a printer which is small and lightweight, portable, and resistant to environmental changes at a low cost.

[0006]

A printer scanning device of the present invention comprises a printer base frame, a recording head, and a carriage on which the head is mounted, and guides when the carriage moves for recording. The guide part is formed by sandwiching a part of the base frame by two or more projecting parts projecting from the carriage, and the projecting part is the same as the range where the one side projecting part is formed. It is characterized in that the area where the protrusions on one side are formed is offset in the moving direction of the carriage and there is no overlapping portion.

[0007]

1 is a front view of a printer mechanism portion according to an embodiment of the present invention, and FIG. 2 is a side view thereof. 1 is K ₂
It is a carriage made of polyacetal resin containing O-nTiO ₂ and carries a recording head 2 which is a 24-pin impact dot head, and a sliding shaft 3 and a printer base frame which are S.
The end 4a of the base 4 made of PCC moves in the left-right direction in FIG. 1 while keeping its posture constant. That is, at this time, an electric circuit (not shown) is attached to the recording head 2.
Characters can be typed out by sending more signals. The carriage 1 has a belt fixing portion 1d.
Is fixed to the toothed drive belt 9 by
The drive belt 9 is a 96-pole hybrid type carriage motor 11 which is used to drive the motor pinion 11a and the drive gear 12.
Driving force is applied through.

Now, the attitude holding of the carriage 1 and the assembling method thereof will be described in detail. Carriage 1 has sliding shaft 3
And two copper-iron-based sintered metal bushes 1e (which are fixed to the right and left of the shaft hole of the carriage) and are sub-assembled, and a terrace is provided between the two metal bushes 1e. An oiled felt (not shown) is inserted. This prevents the seizure with the sliding shaft 3 due to the high speed movement of the carriage 1.

The projections 1a, 1b and 1c sandwich the above-mentioned base end 4a with a constant gap, and under normal installation and use conditions, the upper portions 1a and 1b are in contact with the base end 4a. Then, the posture of the carriage 1 is determined.
(See FIG. 3) Two protrusions 1a and 1b are provided to reduce the posture change of the carriage 1 due to wear due to long-term use, and to reduce the dimensional change due to contraction of the carriage during injection molding. Instead of making one big protrusion, I make two small ones. The projecting portion 1c sandwiches the base end portion 4a with a slight gap so that the recording head 2 is not destroyed when carrying the printer or due to vibration. Moreover, as can be seen from FIG. 1, the protrusions 1a, 1
Go outside the range marked with b, and on the right side of it, the protrusion 1c
Has been formed. This improves disassembling and assembling of the carriage 1, and prevents damage to the carriage during the assembling process and repair and damage during after-sales service. That is,
After removing the fixing bushes 6a and 6b, the sliding shaft 3, the gap adjusting lever 8 and the carriage 1 are lifted so as not to be caught by the platen 5 and the paper guide 13 and the base end 4 is removed.
It is necessary to remove the protrusions 1a, 1b and 1c from a. At this time, the protrusions 1a, 1b, and 1c are often broken by breaking the base end 4a, which is a big problem at the time of disassembling and assembling, which is also a big obstacle to the automation of assembly. However, when the lower protrusion 1c is formed by removing it from the range where the upper protrusions 1a and 1b are attached as in the present embodiment, and the sliding shaft 3 is removed while rotating in the direction of the arrow 10, the base end 4a is removed. Since the sandwiching gap is widened, it can be easily removed without twisting. For this reason, the base end 4a is connected to the protrusion 1
The clearance when sandwiched by a, 1b, and 1c does not need to take into consideration the twist during assembly, and can be set as small as 0.05 to 0.15 mm because it is only necessary to consider that the tightening margin state will not occur due to dimensional tolerance. .. Therefore, even if vibration is applied during transportation, the possibility that the carriage 1 rattles and the recording head 2 is destroyed can be reduced. It should be noted that, at the time of assembling, if it is assembled while rotating in the direction opposite to the arrow 10, it can be assembled as easily as when disassembling,
Automatic assembly by machine is also possible, and stable quality and low cost printer can be realized. Here, the fixed bushes 6a and 6b are the guide portions 3 at both ends of the sliding shaft 3.
and the sliding shaft 3 and the guide portion 3
Since a and 3b are made eccentric, when the gap adjusting lever 8 is pulled toward you, the sliding shaft 3 rotates in conjunction with each other and the gap between the recording head 2 and the platen 5 widens so that printing can be performed even on thick paper. Is configured. Therefore, as can be seen from FIG. 2, even if the carriage 1 moves left and right, the base end 4a
A gap of 2 mm is provided at the end of the base and a gap of 5 mm is provided at the tip of the protrusion 1c so as not to collide with. Further, the carriage protrusion 1f engages with the recess of the recording head 2 so as to prevent erroneous mounting of another recording head. This is because many models are currently assembled in parallel at the factory, and even if the outer shape is the same, some recording heads are driven at 20v and some are driven at 30v, and if a 20v recording head is mistakenly assembled in a 30v circuit, it will burn out. For this reason, a model that uses a high-voltage 30v recording head as a fool proof is provided with the aforementioned engagement portion. This is also effective in after-sales service and has a great effect on preventing repair mistakes. Here, the base 4 will be described with reference to FIG. The base 4 is provided with portions 4b and 4c which stand upright with respect to the lower surface portion. Vertically rising part 4b
Is provided with an end 4a parallel to the lower surface. Edge 4
A screw fixing portion 4d on the same surface as the end portion 4a is provided at both ends of a. Further, the lower surface portion is provided with a portion 4e hooked on the side frames 7a and 7b. Reference numerals 7a and 7b denote left and right side frames made of a synthetic resin of PBT / ABS alloy containing glass fiber, and a hook portion 4e and a screw fixing portion 4d are fixed to the base 4 by two screws. 6b, both ends of the platen 5, the adjustment lever 8 and the like are fixed. Further, 14 is a carriage motor fixing frame, which applies tension to the drive belt 9 by being pulled by the spring 15 in the direction of the hook portion 4b of the base 4. By providing the vertically rising portion 4b and the end 4a integrally with the base 4, the rigidity of the base 4 in the up-down direction and the front-back direction is significantly improved. Further, by providing the screw fixing portions 4d at both ends of the end portion 4a, the side frame 7a while maintaining the dimensional accuracy of the end portion 4a,
7b can be fixed to the side frame 7a,
The fastening force with 7b is greatly improved, and the rigidity of the entire printer base frame is improved.

[0010]

As described above, the printer scanning device of the present invention comprises a printer base frame, a recording head, and a carriage on which the head is mounted, and guides when the carriage moves for recording. The guide is performed by a part of the frame, and the guide part is formed by two or more protrusions protruding from the carriage sandwiching a part of the base frame, and the protrusion is a range in which one side protrusion is formed. The area where the protrusions on the other side are formed is displaced in the carriage movement direction, and there is no overlapping portion. As a result, only one guide shaft with good roundness and rigidity that does not deform due to the printing force is required.
The number of adjusting parts is less than one pair. Further, even when the carriage is assembled to the printer base frame or when the carriage is disassembled, it is possible to prevent the protrusion from being broken by being pryed by a part of the printer base frame. Therefore, the number of assembly and adjustment parts is small and the adjustment process is small, so that it is possible to obtain a low-priced product that is resistant to environmental changes such as temperature changes, vibrations, and shocks, and has few factors that increase costs. Further, since the weight of the printer main body due to the weight of the guide shaft is suppressed as much as possible, the product has good portability, and the installation place is not particularly limited. In addition, there is no failure such as parts destruction when disassembling in after-sales service, and there is no need to spend wasteful service cost and repair time on the consumer. That is, it is possible to provide a small and lightweight printer that is resistant to environmental changes to the market at a low price.

[Brief description of drawings]

FIG. 1 is a front view of a printer mechanism unit according to an embodiment of the present invention.

FIG. 2 is a side view of a printer mechanism unit according to the embodiment of the invention.

FIG. 3 is a perspective view of a carriage according to an embodiment of the present invention.

FIG. 4 is a perspective view of a base according to an embodiment of the present invention.

[Explanation of symbols]

 1 Carriage 2 Recording Head 3 Sliding Axis 4 Base 5 Platen 6a, 6b Fixed Bushing 7a, 7b Side Frame 8 Adjustment Lever 9 Drive Belt 10 Arrow 11 Carriage Motor 12 Drive Gear 13 Paper Guide 14 Carriage Motor Fixed Frame 15 Spring

Claims (1)

[Claims] 1. A printer base frame, a recording head, and a carriage on which the head is mounted, and guides when the carriage moves for recording by a part of the printer base frame, and the guide portion is the Two or more protrusions protruding from the carriage are formed by sandwiching a part of the base frame, and the protrusions are formed in a region where one protrusion is sandwiched and another protrusion is formed on the other side. The scanning device of the printer is characterized in that there is no overlapped portion in the moving direction of the carriage.