JPH0839886A - Printer - Google Patents

Abstract

PURPOSE:To provide a printer which can prevent a foreign matter from adhering on a bearing and at the same time, reduce the unnecessary load on the movement of a carriage. CONSTITUTION:This printer has a carriage 4, with a printing head mounted on a shaft 2 arranged in parallel with a platen, which is supported by a bearing 10 in a movable manner. In addition, the printer is equipped with a felt ring 16, with an inner diameter coinciding with the outer diameter of a shaft 2, which is installed on the shaft 2 containing lubricant, and a cover body 18 which is detachable from the lateral side of the carrige 4 and restricts the felt ring 16 on the lateral side of the carriage in a non-pressed state, covering the felt ring 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer in which a carriage is movably supported on a shaft by bearings, and the printer is capable of preventing the sliding function of the carriage from being deteriorated by foreign matter such as paper dust.

[0002]

2. Description of the Related Art FIG. 7 shows a general small-sized printer used for issuing receipts. In such a printer, a platen 106 and a shaft 108 are mounted in parallel between side plates 102 and 104 arranged in parallel on a frame 100 which constitutes the printer main body, and the shaft 10
A carriage 110 is attached to the carriage 8 so as to be movable left and right. A print head 112 is mounted on the carriage 110, and a driving force in the left-right direction is given by rotation of a drive shaft 114 mounted between the side plates 102 and 104. The drive shaft 114 is supplied with the rotational force of the motor 116 through the gear mechanism 118, and the printing operation by the print head 112 is performed by the rotation of the drive shaft 114. Therefore, the printing quality depends on the movement accuracy and the printing speed. Is carriage 1
It depends on the moving speed of 10.

Next, FIG. 8 shows an outline of a bearing mechanism of the carriage 110. The carriage 110 is a carriage for carrying the print head 112, and has a constant width in the axial direction of the shaft 108. In order to stably support such a carriage 110 on the shaft 108, the carriage 110 has a pair of bearings 12 in the axial direction.
2, 124 are provided. And conventionally, each bearing 12
2, 124 are exposed on the side surface of the carriage 110.

However, when foreign matter such as paper powder adheres to the shaft 108, the bearings 122 and 124 and the shaft 108
The foreign matter intrudes into the gap 126 between them, which hinders the movement of the carriage 110 and becomes unstable, and the foreign matter that has entered causes the bearings 122 and 124 to be significantly worn.

[0005]

Conventionally, in order to prevent such inconveniences, JP-A-3-81753 "Printer", JP-A-64-55048 "Recording device", JP-A-2-95654 "Lubrication""Device" is proposed. These are intended to mount a felt on the outside of the bearing, remove the foreign matter on the shaft by the felt that moves together with the carriage, and prevent the foreign matter from entering the gap between the bearing and the shaft.

As a general view of these prior arts, a felt for preventing foreign matter from entering the inside of a bearing is fixed to a side surface of a carriage in a pressed state by a detachable support metal fitting (Actual Publication No. 3-81753). And that felt attached in an exposed state (Shokai 64-55048,
It can be roughly divided into the actual Kaihei No. 2-95654).

By the way, when the felt is supported by the support fitting in a pressed state, as shown in FIG.
A slight displacement or misalignment occurs between the center O of 08 and the center Q of the ring-shaped felt 128, and the felt 128 is deformed by pressing. Such felt 12
The misalignment and deformation of 8 and the pressing force of the supporting metal fitting cause an excessive frictional force between the carriage 110 and the shaft 108 through the felt 128, which acts as a load against the movement of the carriage 110. However, if the prevention of foreign matter from entering is increased, there is a disadvantage that the printing speed is reduced.

Further, when the felt is exposed, there is no inconvenience such as pressing, but foreign matter such as paper dust is easily attached to the felt, and when the paper dust is attached to the felt, the felt is impregnated. Since the paper dust absorbs the lubricating oil that has been made available, the felt is deficient in oil, and as a result, the bearing and the felt are worn away, and the attached felt is meaningless.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a printer capable of reliably preventing foreign matter from entering a bearing and reducing an unnecessary load on the movement of the carriage.

[0010]

The printer of the present invention, as illustrated in FIG. 1, includes a print head (11) on a shaft (108, 2) disposed parallel to a platen (106).
2) Carriage (110, 4) for mounting bearings (12
2,124,8,10) movably supported by a felt, the inner diameter of which is set to match the outer diameter of the shaft, and which is impregnated with lubricating oil and attached to the shaft. A ring (16),
A cover body (18) detachably attached to the side surface of the carriage to cover the felt ring and restrain the felt ring to the side surface of the carriage in a non-pressed state.
It is provided with.

In this printer, the felt ring may be a complete annular body or a partially detached annular body as long as it surrounds the shaft.

Further, in this printer, with respect to the form in which the felt ring is held, a protrusion (12, 14) surrounding the bearing is provided on the side of the carriage, and the felt is attached to the cover body corresponding to this protrusion. Form a recess (22) into which the annulus is inserted.

Further, in this printer, for convenience of replacement of the felt ring, an attaching / detaching mechanism (30) for attaching and detaching the cover body is provided between the carriage and the cover body.

The attaching / detaching mechanism uses the elastic force of the constituent materials of the carriage and the cover body in order to easily attach / detach and securely restrain the felt ring.
8).

[0015]

In the printer according to the present invention, the felt ring installed on the side surface of the carriage is covered with the cover body and closely adhered to the shaft inside the cover body, and is restrained inside the cover body in a non-pressed state. Has been done. Since the felt ring is covered with a cover, the adhesion of foreign matter such as paper powder is suppressed. As a result, the impregnated lubricating oil is prevented from flowing out and evaporated, and the felt ring stabilizes the removal of foreign matter on the shaft. You can do it. Further, since the felt ring is constrained inside the cover body, the felt ring moves quickly on the shaft as the carriage moves.
Since the felt ring is in the non-pressed state, the felt ring is not deformed or misaligned, and the adhesion of the felt ring to the shaft is not impaired. Its elasticity is maintained and its life is extended.

Further, in this printer, the felt ring may be a complete annular body or a partially detached annular body as long as it surrounds the shaft, and foreign matter can be removed in any form. Becomes Even when an annular body is formed by separating a part, the constraint in the non-pressed state by the cover body helps maintain the shape of the felt ring, and a stable foreign substance removing function can be obtained.

Further, regarding the form in which the felt ring is held, the side part of the carriage is provided with a projecting part surrounding the bearing,
By forming a concave portion into which the felt ring is inserted corresponding to the protruding portion, the felt ring can be restrained in a non-pressed state and held on the side portion of the carriage. Moreover, the volume occupied by the cover body for restraining and holding the felt ring can be reduced.

If the attaching / detaching mechanism for attaching / detaching the cover body is provided between the carriage and the cover body, the felt ring can be easily replaced.

The attaching / detaching mechanism is provided with the hooking means utilizing the elastic force of the constituent materials of the carriage and the cover body, so that the mechanism is simplified and the attaching / detaching of the felt ring is ensured. Therefore, the foreign matter on the shaft can be removed, and the foreign matter can be prevented from entering the bearing.

[0020]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIGS. 1, 2 and 3 show an embodiment of the printer of the present invention and show the structure of the carriage.

The shaft 2 is the shaft 108 in the printer of FIG. 7, and the carriage 4 supported by the shaft 2 is the same as the carriage 110 of FIG.
A platen 106 is arranged parallel to the shaft 2, and a print head 112 (FIG. 7) is mounted on the carriage 4. Therefore, printing by the print head mounted on the carriage 4 is performed along with the horizontal movement of the carriage 4, and the movement is realized by the rotation of the drive shaft 114 (FIG. 7). In short, even in the printer of the present invention,
Except for the carriage 4, the other mechanism has the same structure as the conventional printer.

The shaft 2 is a side plate (a side plate 102 shown in FIG.
104) and is made of, for example, a wear-resistant metallic material. On the other hand, the carriage 4 is
It is molded from a resin such as acetal as a material suitable for reducing its weight and mechanical strength, and a pair of bearings 8 and 10 are firmly fixed to the bearing support portion 6 by press fitting or the like. Each of the bearings 8 and 10 may be fixed to the bearing support portion 6 with an adhesive.

The bearing support 6 is formed with elliptical projections 12 and 14 surrounding the bearings 8 and 10, and a felt ring 16 is installed on the surface of each projection 12 and 14. The form of this felt ring 16 has a certain thickness,
The outer diameter is the same as the minor diameter of the protrusions 12 and 14 forming the oval shape, and the inner diameter corresponds to the outer diameter of the shaft 2. That is,
The inner diameter is set to be the same as or slightly smaller than the outer diameter of the shaft 2 in order to enhance the close contact with the shaft 2. Further, the felt ring 16 is impregnated with a lubricating oil in order to enhance lubricity with the shaft 2.

A cover body 18 is installed on the side surface of the carriage 4 as a means for covering the side surface of the carriage 4 with the felt ring 16 and restraining and holding the felt ring 16 in a non-pressed state. Like the carriage 4, the cover body 18 is also made of resin.

The cover body 18 is provided with a body portion 20 having an elliptical shape that matches the protrusion portions 12 and 14 having an elliptical shape on the carriage 4 side.
A recess 22 into which the shaft 2 can be gently inserted and a through hole 24 for allowing the shaft 2 to pass therethrough are formed. The recess 22 has a circular shape corresponding to the shape of the felt ring 16, but its depth is slightly larger than the thickness of the felt ring 16 and its diameter is set to be slightly larger than the outer diameter of the felt ring 16. There is. This is the reason why a slight gap 26 is formed between the felt ring 16 and the cover body 18. The reason why the gap 26 is formed is that the felt ring 16 is covered with the cover body 18.
This is for restraining and holding in a non-pressed state. In the case of this embodiment, the side surface of the cover body 18 has a window 28.
Are formed. The state of the felt ring 16 can be seen through the window 28. The formation of the window portion 28 is optional, and the felt ring 16 may be entirely covered with the cover body 18 without forming the window portion 28.

Then, the cover body 18 and the carriage 4
Between the two, both are fixed and the felt ring 16
An attachment / detachment mechanism 30 is provided for exchanging the components and attaching / detaching the cover body 18 to / from the carriage 4. That is, each of the protrusions 12 and 14 on the carriage 4 side is formed with a protrusion 32 having a width in the axial direction from the lower edge thereof, and a locking protrusion 34 as hooking means is provided on the upper edge thereof. Has been formed. On the other hand, in the cover body 18, as shown in FIGS. 4, 5 and 6, a C-shaped locking frame 36 corresponding to the protrusion 32 on the lower surface side of the carriage 4 is orthogonal to the main body portion 20. C-shaped locking claws 38 for locking the locking projections 34 are formed on the upper side thereof. The notch 40 formed in the locking frame 36 is
When the locking frame 36 is engaged with the protrusion 32 on the carriage 4 side, or when the engaged locking frame 36 is removed from the protrusion 32, the main body 20 is displaced from the carriage 4 and separated. It is what makes me. Further, the window 42 formed in the vertical portion of the locking claw 38 is for imparting appropriate elasticity to the locking claw 38.

With the above construction, the felt ring 16 can be restrained and held by the carriage 4 in a non-pressed state, and an increase in load due to deformation of the felt ring 16 can be prevented.

Further, since the felt ring 16 is covered by the cover body 18, it is possible to suppress the adhesion of foreign matter such as paper powder, and prevent evaporation and suction of the lubricating oil due to the foreign matter adhesion as in the conventional case. It is possible to reliably prevent foreign matter from entering the space between the bearing 10 and the shaft 2, prevent the carriage 4 from moving, and prevent the printing speed from decreasing. Then, stable carriage conveyance can be maintained for a long period of time. Moreover, the number of times the felt ring 16 is replaced can be reduced.

When assembling the printer, the shaft 2 can be passed through the carriage 4 after the felt ring 16 is installed on the side surface of the carriage 4 and the cover body 18 is attached. Further, in the case of maintenance, the cover body 18 is detached from the carriage 4 on the shaft 2 by utilizing its elastic force, the felt ring 16 is cut off from the shaft 2, or the felt ring 16 partially cut off is removed. It can be removed. In the case of the felt ring 16 made of an endless body, the shaft 2 can be detached from the printer main body and attached to the shaft 2, and in the case of the felt ring 16 having a notch in a part thereof, the shaft 2 The felt ring 16 can be easily attached to the. Then, the cover body 18 can be fixed to the carriage 4, and the felt ring 16 can be restrained and held.

The attachment / detachment of the cover body 18 on the shaft 2 will be described. When the engagement claws 38 of the cover body 18 are removed from the engagement protrusions 34 of the carriage 4, tension between the carriage 4 and the cover body 18 is generated. Loosen, the protrusion 3 of the carriage 4
It is possible to remove the locking frame 36 from 2. As a result, the cover body 18 is separated from the carriage 4, and the cover body 18 can move freely on the shaft 2. With the carriage 4 and the cover body 18 separated from each other, the felt ring 16
Can be removed from the shaft 2.

When the cover body 18 is attached to the carriage 4, the protrusion 32 of the carriage 4 is fitted with the locking frame 36 of the cover body 18 with the felt ring 16 installed on the side surface of the carriage 4. While the main body 20 is in contact with the protrusion 12 or 14 of the carriage 4, the locking claw 38 is pulled up onto the locking projection 34, and the tip end thereof is locked by the locking projection 34.
Hook inside. Such work is performed by the cover body 18
This is done by using the elasticity of. Cover body 1 on carriage 4
When 8 is bonded, the bonding strength of both resins can be further increased by setting the molding accuracy of both resins to be high.

A durability test was conducted on the printer using the carriage of this example. As a result, when the felt ring 16 was not provided, the printing speed was reduced to 800,000 times. It was confirmed that the printing speed did not decrease even after 2.5 million times or more, and the life could be extended three times or more.

[0034]

As described above, according to the present invention,
The following effects can be obtained. a. It is possible to prevent the foreign matter intrusion preventing member such as a felt from deteriorating in function, reduce an unnecessary load on the movement of the carriage, and maintain a stable printing operation for a long period of time. That is, the felt ring is covered with the cover body, and is closely adhered to the shaft inside the cover body. The felt ring is restrained inside the cover body in a non-pressing state and is covered with the cover body. As a result, the felt ring is impregnated. The lubricating oil is prevented from flowing out and evaporating, and foreign matter on the shaft can be removed stably. Also, since the felt ring is restrained inside the cover body, the felt ring is separated by the movement of the carriage. In addition, since the felt ring is in a non-pressed state when it is restrained, deformation of the felt ring and misalignment of the center of the felt ring do not occur. Since the felt ring is not damaged, the elasticity of the felt ring is maintained, the life of the felt ring is extended, foreign matter on the shaft can be removed for a long time, and stable printing speed is maintained. It can be.

B. The felt ring can be a complete annular body or a partially separated annular body as long as it surrounds the shaft. In any form, foreign matter can be removed, and part of the felt ring can be removed. Even in the case of the separated annular body, the constraint in the non-pressed state by the cover body helps maintain the shape of the felt ring, and a stable foreign substance removing function can be obtained.

C. Regarding the form that holds the felt ring, a protrusion that surrounds the bearing is provided on the side of the carriage,
By forming the concave portion into which the felt ring is inserted in the cover body corresponding to this protruding portion, the felt ring can be restrained in the non-pressed state and can be held on the side portion of the carriage, and further, the felt ring can be held. The volume occupied by the cover body for restraining and holding the can be reduced.

D. An attachment / detachment mechanism for attaching / detaching the cover body is provided between the carriage and the cover body, so that the felt ring can be easily replaced and maintenance can be facilitated.

E. Further, the attaching / detaching mechanism is provided with a hooking means utilizing the elastic force of the constituent materials of the carriage and the cover body, so that the mechanism can be simplified and the felt ring can be restrained easily and easily. It is possible to prevent foreign substances on the shaft from being removed and prevent foreign substances from entering the bearing.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a carriage portion that is an embodiment of a printer of the present invention.

FIG. 2 is a front view of the carriage shown in FIG.

FIG. 3 is a sectional view of the carriage shown in FIG. 1 taken along line 3-3.

FIG. 4 is a front view of a felt ring and its cover body in the carriage shown in FIG.

5 is a bottom view of the felt ring and its cover body in the carriage shown in FIG. 1. FIG.

FIG. 6 is a rear view of the felt ring and its cover body in the carriage shown in FIG.

FIG. 7 is a plan view showing a general small printer.

FIG. 8 is a cross-sectional view showing an outline of a conventional carriage bearing mechanism.

FIG. 9 is a diagram showing misalignment of a felt ring with respect to a shaft.

[Explanation of symbols]

 106 Platen 2,108 Shaft 4,110 Carriage 112 Print Head 8,10,122,124 Bearing 12,14 Projection 16 Felt Ring 18 Cover Body 22 Recess 30 Detachment Mechanism 38 Locking Claw (Hooking Means)

Claims (5)

[Claims] 1. A printer in which a carriage, on which a print head is mounted, is movably supported by bearings on a shaft arranged in parallel with a platen, the inner diameter of which is set to match the outer diameter of the shaft. ,
A felt ring impregnated with lubricating oil and attached to the shaft; and a felt ring detachably attached to the side surface of the carriage to cover the felt ring and constrain the felt ring to the side surface of the carriage in a non-pressed state. A printer comprising: a cover body. 2. The printer according to claim 1, wherein the felt ring is a complete annular body or an annular body formed by separating a part thereof. 3. A protrusion, which surrounds a bearing, is provided on a side portion of the carriage, and a recess into which the felt ring is inserted is formed in the cover body corresponding to the protrusion. The listed printer. 4. The printer according to claim 1, further comprising an attachment / detachment mechanism for attaching / detaching the cover body between the carriage and the cover body. 5. The printer according to claim 4, wherein the attachment / detachment mechanism includes a hooking unit that utilizes elastic force of the constituent materials of the carriage and the cover body.