JPH0430202Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a sheet conveying device in an impact printer used for MICR or the like.

(Prior Art) Conventionally, a sheet conveying device in this type of printer device has a sheet guide member fixed to the upper surface of the printer main body board, the upper end of which opens at a predetermined angle and supports the sheet in an upright state. A feed roller member, a printing mechanism, and a discharge roller member are arranged to sandwich the guide member from one end to the other end, and the sheet within the guide member is conveyed at a predetermined speed by the feed roller member and the discharge roller member. I try to let them do it. The feed roller member pinches the front and back sides of the sheet and transports it to the printing mechanism, while the discharge roller member pinches the front and back sides of the sheet after printing and discharges it out of the printer main body.

Incidentally, in the discharge roller member, both the driving roller and the driven roller constituting the discharge roller member have a cylindrical shape, and apply a uniform tensile force to the sheet in the thickness direction of the roller. For this reason, if the ejection roller member is located close to the printing mechanism and the distance to the ejection side edge of the board is set extremely short, the sheet will not be able to flow from the ejection side edge of the board to the outside. When the fed-out portion passes about half of its total length, it will come off the discharge roller member due to its own weight and fall outside the board, and in some cases, the rear part of the sheet in the direction of travel may be completely damaged. This may result in a situation where printing is not possible. In order to avoid this situation, either increase the distance from the ejection roller member to the ejection side edge of the board and ensure that the rear part of the sheet is supported by the guide member in this area, or move the ejection roller member from the printing mechanism. It is conceivable to provide a sufficient distance between the two ends of the substrate so that the sheet does not fall from the end of the substrate on the discharge side during printing. However, with such a solution, the length of the substrate and guide member from the printing mechanism to the ejection side end becomes long, resulting in a problem that the printer device becomes larger.

(Purpose) In view of these problems, the present invention has been developed to ensure that the sheet is narrowed all the way to the rear of the sheet without causing any hindrance to the printing operation even when the distance from the printing mechanism to the discharge side end of the board is short. It is an object of the present invention to provide a conveying device that can hold and convey.

(Means for Solving the Problem) In order to achieve the above-mentioned object, the present invention slides the lower end of the sheet between two guide plates facing each other at a predetermined distance on the upper surface of the board of the main body of the printer. A transport guide member provided with a freely supporting horizontal transport surface is fixed, and a sheet between the guide plates is transported by a discharge roller member comprising a driving roller and a driven roller disposed oppositely so as to fit between the guide plates. In a sheet conveyance device in a printer device, which conveys the sheet from the printing mechanism to the outside of the printer device in an upright state by holding the front and back surfaces of the The rollers are formed into truncated conical shapes with different diameters, and the other roller is cylindrical with the upper and lower parts of the same diameter, and the circumferential surface is large enough to be integrally abutted from the upper part to the lower part of the one roller. By forming the rollers to have a certain height and tilting the rotating shaft of at least one of the two rollers, the circumferential surfaces of both rollers are brought into close contact with each other, and the difference in circumferential speed between the upper and lower parts of the contact area of both rollers is compensated for. Therefore, a counterclockwise rotational moment is generated in the conveyed sheet, and a reaction force against the rotational moment generated at the rear lower end corner of the sheet that is in contact with the conveyance surface causes the sheet to rotate clockwise. This is characterized in that it generates a correction moment of .

(Example) The present invention will be described in detail below based on the illustrated example.

FIG. 1 shows a main body of a printer device incorporating a conveyance device according to an embodiment of the present invention.

Reference numeral 1 in the drawing designates a guide member for conveying a sheet that is fixed to the upper surface of the main body of the apparatus slightly from the center of the upper surface of the substrate 2 so as to horizontally traverse from one end of the substrate 2 to the other end.

This guide member 1 is for supporting the lower part of the sheet as a print medium and horizontally transporting it to the discharge side, and has one vertical guide plate 11a at the upper part as seen in FIG. The guide main body 11 has a fixing part 11b fixed to the substrate 2 at the lower part thereof, and the guide main body 1 is arranged such that the upper end thereof is open at a predetermined angle with respect to the guide plate 11a.
A conveyance surface 13 is provided between both guide plates 11a and 12 to support and guide the lower end of the sheet.

A plurality of openings are formed in the plate surfaces of the guide plate 11a and the inclined guide plate 12. From this opening, the feed roller member 3, printing mechanism 4, and discharge roller member 5, which will be described later, are connected to both guide plates 11a,
They are designed to enter into 12 gaps and perform predetermined operations on each sheet.

A pair of feed roller members 3 are fixed to the upper surface of the substrate 2 located on the sheet input side so as to sandwich the guide member 1 from the front and rear. This feed roller member 3 is for conveying the sheet supported by the guide member 1 to the printing mechanism 4 at a predetermined speed.
It is composed of a driving roller 31 and a driven roller 32.

The drive roller 31 has a normal cylindrical cross-sectional shape with the upper and lower diameters being the same, and is directly fixed to the tip of a drive shaft of a step motor 33 disposed on the lower surface of the substrate 2. The outer circumferential surface of the driving roller 31 that has entered the gap between the guide plates 11a and 12 has a sufficient height to be in close contact with the circumferential surface of the driven roller 32 from the top to the bottom. The positioned portion is located slightly closer to the type head 41 than the center line of the gap.

On the other hand, the driven roller 32, like the driven roller 52 of the discharge roller 5 shown in FIG. 2, is formed in a truncated conical shape with an upper part having a slightly smaller diameter than a lower part.
This driven roller 32 is moved laterally by the action 34, which will be described later, so that it can be displaced between a position where it contacts the circumferential surface of the drive roller 31 and a position where it escapes outward from the circumferential surface of the drive roller 31. It is rotatably attached to a U-shaped bracket 35 that can swing in the direction via a rotating shaft 32b. The rotating shaft 32b rotates around the circumferential surface 3 of the driven roller 32 such that the circumferential surface 32a of the driven roller 32 contacts the circumferential surface 31a of the drive roller 31.
It is inclined by an inclination angle of 2a.

The actuating body 34 is composed of a solenoid that operates based on a signal when a sheet is introduced into the guide member 1, and has one side fixed to an angle 36 mounted on the base plate 2. One end of the side wall of the bracket 35 is connected to the end of the angle 36 on the guide member side via a hinge 37, and is connected to the plunger 34a of the actuating body 34 fixed to the side wall 35a. It is constructed so that it can perform a rocking motion. The angle of inclination of the upper and lower parts of the driven roller 32 is determined by considering the thickness of the roller 32 itself or the thickness of the sheet, and is set to 1 degree in this embodiment, for example.

Incidentally, the displacement of the driven roller 32 may be directly performed by the forward and backward movement of the plunger of the actuating body 34.

Further, on the upper surface of the substrate 2 located on the upper end side of the guide member 1 in FIG. is fixed. The ejection roller member 5 is for sending out the sheet being printed and the sheet after printing has been completed to the outside of the printer main body, and is arranged at a distance shorter than the length of the sheet from the feed roller member 3. drive roller 51 and driven roller 5
It is composed of 2.

The drive roller 51 has exactly the same structure as that of the feed roller member 3, and is
It rotates under the driving force of a step motor 53 fixed to the lower surface.

On the other hand, the driven roller 52, like the driven roller 32 in the above-described feed roller member 3, is formed in a truncated conical shape with an upper part having a slightly smaller diameter than a lower part, and is rotated by a bracket 54 fixed at a predetermined position on the substrate 2. It is freely supported. The difference in diameter between the upper and lower parts of this roller 52 is also the same as that of the feed roller member 31 mentioned above.
It is done in the same way as in the case of . In the figure, reference numeral 51a indicates the outer surface of the driving roller 51, and 52a indicates the outer circumferential surface of the driven roller 52, which correspond to the reference numerals 31a and 32a of the feed roller 3 described above, respectively.

Reference numerals 41 and 42 denote a type head and a hammer member that constitute the printing mechanism 4.
is constructed by arranging a solenoid in which a synthetic resin hammer tip is removably fitted to the tip of a plunger portion in close proximity to and facing the type head 41.

Reference numeral 6 denotes an ink ribbon cassette coated with magnetic ink, which is directly driven by a step motor 61, which is a unique drive mechanism fixed to the bottom surface of the substrate 2, like the components constituting the printer main body described above. Ru.

Reference numeral 7 indicates a pair of sheet horizontal direction detection sensors installed at the end of the guide member 1 on the sheet input side so as to sandwich the guide member 1. Reference numeral 8 indicates the guide member 1 located between the feed roller member 3 and the type head 41. These sensors 7 and 8 detect folding or tilting of the sheet, and reverse or stop the drive roller 31 of the sheet feed roller depending on the case. etc. to ensure horizontal sheet feeding.

The conveyance status of sheets will be explained. The present invention is characterized by the sheet ejection roller member.
In this embodiment, since the feed roller member has the same structure as the discharge roller member, the operation of the feed roller member will be explained in detail.

When the sheet S is introduced into the guide plate 11, the actuating body 34 operates based on the command to sandwich the sheet S between the driving roller 31 and the driven roller 32 of the feeding roller. At the same time, the step motor 33 of the drive roller 31 is driven to convey the sheet S toward the type head 41.

At this time, for example, if the sheet S is inserted with its front end raised as shown in FIG. 3A,
The drive roller 31 and the driven roller 32 of the feed roller member 3 rotate with their circumferential surfaces in close contact, and the circumferential speeds differ between the upper and lower portions of the driven roller 32. A large arc-shaped force (counterclockwise moment) acts on the lower point, which is indicated by the arrow in the figure. As a result,
As the sheet S moves forward, a force that tries to lift the sheet S acts in front of the roller 32, while a force that tries to push the sheet S down acts in the rear. However, since the rear end of the sheet S is in contact with the conveyance surface 13 of the guide member 1, the sheet S is subjected to a reaction force. The moment of this reaction force is
Because the distance from the center point of the rollers 31 and 32 to the contact portion is long, the force exceeds the force that lifts the front end of the sheet S, and this force is canceled out and the front end of the sheet is pushed up (see Fig. 3). (b) Finally, the sheet S is made horizontal as shown in Fig. 3 (c). On the other hand, the driven roller 32 exerts a similar force on the sheet S' which is loaded with its rear end lifted as shown in FIG. 4A. In this case, since the front end of the sheet S' is in contact with the guide, the above-mentioned force acting on the left half of the roller 32 results in a counterclockwise rotational moment about the contact point as a fulcrum. appears as a sheet
It functions to gradually push down the rear end of S′ (fourth
Figure b). Therefore, the sheet S' is transported horizontally as in the above example (FIG. 4C).

Note that for sheets S and S' that are not properly lifted at the front and rear ends, the horizontal direction detection sensor 7 or the vertical direction detection sensor 8 works to reverse the driving roller 31 of the feed roller member 3, etc. , the sheets S, S' are moved back and forth within the guide plate 11 to move them to a horizontal state.

When the sheet S comes to the position of the type head 41, the type head 41 is rotated by a predetermined angle by a step motor 43 driven by a print command, and the hammer member 42 acts at a desired position of the type.

The sheet S that has passed through the type head 41 is transferred to the discharge roller member 5, and is discharged to the outside from the upper side of the guide member 1 in FIG. 1 under the tension thereof.

At this time, the discharge roller member 5 performs the same action as the feed roller member 3 on the printed sheet because the circumferential surface of the truncated conical driven roller 52 rotates in close contact with the circumferential surface of the drive roller. . That is, due to the feeding operation of the discharge roller member 5, a counterclockwise moment with the lower point at the pressure contact center line position of the driven roller 52 and a clockwise moment due to a reaction force from the rear lower end of the sheet S are applied to the sheet. act. When the entire lower end of the printed sheet S is in contact with the conveyance surface 13 of the guide member 1, these acting forces are canceled and the sheet S is guided horizontally along the conveyance surface 13.

The sheet S advances and its front end is placed on the conveying surface 1.
3, even if the clockwise moment described above acts more strongly than the counterclockwise moment, when the rear lower end of the sheet S lifts off from the conveying surface 13, the clockwise moment As a result, the horizontal conveyance state described above is maintained.

The sheet S further advances and most of it is transferred to the conveying surface 13.
When the discharge roller 5 protrudes forward, the distance between the center of pressure contact of the discharge roller 5 and the rear lower end of the sheet S becomes shorter, and the clockwise moment becomes smaller than the counterclockwise moment. As a result, the sheet is ejected from the guide member 1 with its front end lifted by the counterclockwise moment of the upward rotation.

Therefore, even if there is only a very short distance from the printing mechanism 4 to the discharge side end of the substrate 2, the printed end of the sheet S cannot be slid off from the discharge side end of the substrate 2 due to its own weight. This allows the sheet to be transported reliably by holding the trailing edge of the sheet without being stowed away.

The magnitude or strength of the above-mentioned counterclockwise moment and clockwise correction moment with respect to the printed sheet depends on the inclination angle of the circumferential surface of the truncated conical roller of the discharge roller member and both the driving and driven forces. It is appropriately set depending on the degree of adhesion of the rollers, the thickness and quality of the sheet to be conveyed, or the contact position of the feed roller to the sheet.

Furthermore, it goes without saying that the present invention can be similarly applied to cases where the feed roller member has the same shape as the conventional one. Further, in the above embodiment, the driven roller of the discharge roller member is formed in a truncated conical shape, but the present invention is not limited to this, and the driving roller may have such a shape.

(Effects) As described above, according to the present invention, either the drive roller or the driven roller of the discharge roller member that pinches the printed sheet and conveys it out of the printer main body is formed into a truncated cone shape. death,
Due to the difference in circumferential speed between the upper and lower contact areas of both rollers, a counterclockwise rotational moment and a counterclockwise correction moment are generated in the sheet by a reaction force to the rear lower end of the sheet against this rotational moment. At first, the sheet is fed out horizontally in an extension of the conveying surface of the guide member, and when it protrudes from the ejection side end to some extent, the front end is slightly lifted and the sheet is sent out of the printer main body. It can be discharged. Therefore, even if the distance from the printing mechanism to the discharge side end of the board is short, the sheet can be reliably held and discharged all the way to the rear end, without interfering with the printing operation, and moreover, even if the distance from the printing mechanism to the discharge side end of the board is short, the sheet can be discharged without interfering with the printing operation. This can contribute to the miniaturization of.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a main body of a printer incorporating a conveying device according to an embodiment of the present invention, and FIG.
The left side view of the figure, FIGS. 3A to 4D and 4A to 3C are explanatory diagrams showing the working state of the feed roller member in the sheet transport mechanism, and FIG. 5 is the working state of the discharge roller member in the sheet transport mechanism. FIG. In the figure, numeral 1 is a guide member, 11 is a guide main body,
12 is an inclined guide plate, 2 is a substrate of the main body of the printer, 3 is a feed roller member, 31 is a drive roller, 3
2 is a driven roller, 4 is a printing mechanism, 41 is a type head, 42 is a hammer member, 5 is a discharge roller member,
51 is a driving roller, 52 is a driven roller, 6 is an ink ribbon cassette, 33, 43, 53, and 61 are step motors, and S and S' are sheets, respectively.

Claims (1)

[Claims for Utility Model Registration] A conveyance guide comprising a horizontal conveyance surface that slidably supports the lower end of a sheet between two guide plates facing each other at a predetermined distance on the upper surface of a substrate of a printer main body. With the member fixed, the front and back surfaces of the sheet between the guide plates are sandwiched by a discharge roller member consisting of a driving roller and a driven roller attached so as to fit between the guide plates, and the printing mechanism is operated with the sheet in an upright state. In a conveying device for a sheet in a printer device, which conveys a sheet from the sheet to the outside of the printer device, one of the driving roller and the driven roller is formed into a truncated conical shape with an upper and lower part having different diameters, and the other roller is formed into a truncated conical shape, and the other roller is , whose upper and lower parts have a cylindrical shape with the same diameter, and whose circumferential surface has a sufficient height to be integrally abutted from the upper part to the lower part of one of the rollers, and at least one of the two rollers. By tilting the rotating shaft, the circumferential surfaces of both rollers are brought into close contact, and due to the difference in circumferential speed between the upper and lower contact areas of both rollers, a counterclockwise rotational moment is applied to the conveyed sheet. , and a clockwise correction moment is generated in the sheet by a reaction force against the rotational moment, which is generated at the rear lower end corner of the sheet in contact with the conveyance surface. A sheet conveying device in a printer device.