DOCUMENT FEEDING DEVICE AND METHOD FOR ASSEMBLING DOCUMENT FEEDING DEVICE

Abstract

The present invention provides a document feeding device whose components are easily assembled. A document feeding device includes a housing base unit and a drive unit, the housing base unit forming a document transportation path, and including a roller shaft including a roller and a driven gear, the drive unit transmitting power to the roller shaft, and including a drive gear meshing with the driven gear, and when the drive unit is mounted in the housing base unit, the drive gear being positioned on an upper or lower side of the driven gear to mesh with the driven gear.

Description

The present invention relates to a document feeding device and a method for assembling a document feeding device.

BACKGROUND ART

PTLs 1 to 3 are Patent Literatures disclosing a document feeding device.

FIG. 8 is a diagram illustrating a configuration of a document feeding device of the related technique. The document feeding device includes a housing base unit 4 and a drive unit 6.

FIG. 9 is a diagram illustrating a configuration of the drive unit 6 in the document feeding device of the above-mentioned related technique. The drive unit 6 includes a motor 1, a drive transmission system 2, an output shaft 3, and a control device 5.

A main function of the document feeding device is to feed documents one by one and cause the documents to pass through a reading unit at a constant speed. This function is implemented by transmitting the power of input shaft corresponding to the motor 1 to the output shaft 3 by the drive transmission system 2. The drive transmission system 2 is constituted by transmission members such as gears and belts. A form and a quantity of the gears and the belts are appropriately changed so as to achieve a transporting speed of a document corresponding to a reading speed of the device. As the output shaft 3, a rubber roller is attached to the roller shaft with a driven gear. For the roller of the output shaft 3, a driven roller making a pair exists, and via friction between this pair of rollers, a document is transported. The number of rollers used as the output shaft 3 is rarely one, and a plurality of rollers are usually used in combination. There are various applications and functions of the rollers thereof. The roller, for example, includes a paper feeding roller that feeds documents one by one, a reading roller that plays a role of stable document transportation near the reading unit, and a paper discharging roller that is provided in front of a paper output tray, and drives out a document, and the like.

Sharing a mounting space, such various constituent elements are incorporated inside the device, mainly in the housing base unit 4 that forms a document transportation path.

Assembling of the drive unit 6 forming a transmission path includes work of regularly arranging a large quantity of gears to be directed to a plurality of output shafts, and work of arranging the control device 5 at an intermediate position of the transmission path and performing harness processing, which causes difficulty in assembling. A fault in the assembling work generates irregularity in transmission of the drive unit 6, and the irregularity of this transmission leads directly to nonuniformity in a read image. In other words, precision in transmission of the drive unit 6 directly influences reading quality of a document so that highly precise assembling is required.

In the document feeding device illustrated in FIG. 8 and FIG. 9, work of mounting, from the horizontal direction, gears in the laterally long housing base unit 4 forming the document transportation path is standard. In other words, first, one (“a” in FIG. 9) of two side plates of the drive unit 6 is attached to the housing base unit 4, and respective roller shafts are fixed. Next, gears are attached to the respective roller shafts, and are sandwiched and fixed by the other one side plate (“b” in FIG. 9). This is mounting in the members receiving the output shaft rollers, and for this reason, can be regarded as highly precise component mounting.

CITATION LIST

Patent Literature

[PTL 1] Japanese Laid-open Patent Publication No. 2012-180217

[PTL 2] Japanese Laid-open Patent Publication No. 2009-182949

[PTL 3] Japanese Laid-open Patent Publication No. 2004-026500

SUMMARY OF INVENTION

Technical Problem

The following problem, however, exists in the document feeding device illustrated in FIG. 8 and FIG. 9. In other words, the work of mounting, from the horizontal direction, gears in the laterally long housing base unit 4 forming the document transportation path lacks in efficiency in that the work has to be performed with the laterally long housing base unit being kept standing upright, or the like. Further, an additional jig such as a jig for holding the housing standing upright is needed for performing this work.

An object of the present invention is to provide a document feeding device and a method for assembling a document feeding device, which solve the above-described problem.

Solution to Problem

A document feeding device according to the present invention is a document feeding device including a housing base unit and a drive unit, wherein the housing base unit forms a document transportation path, and includes a roller shaft including a roller and a driven gear, the drive unit transmits power to the roller shaft, and includes a drive gear meshing with the driven gear, and when the drive unit is mounted in the housing base unit, the drive gear is positioned on an upper or lower side of the driven gear to mesh with the driven gear.

A method for assembling a document feeding device according to the present invention is a method for assembling a document feeding device including a housing base unit and a drive unit, wherein the housing base unit forms a document transportation path, and includes a roller shaft including a roller and a driven gear, the drive unit transmits power to the roller shaft, and includes a drive gear meshing with the driven gear, and when the drive unit is mounted in the housing base unit, the drive gear is positioned on an upper or lower side of the driven gear to mesh with the driven gear, the method including a step of mounting the drive unit in the housing base unit from an upper or lower direction at the time of the meshing.

Advantageous Effects of Invention

According to the present invention, it is possible to provide a document feeding device and a method for assembling a document feeding device, in which components are easily assembled.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram illustrating a configuration of a document feeding device 10 according to a first exemplary embodiment.

FIG. 2 is a perspective view illustrating external appearance of a document feeding device 20 according to a second exemplary embodiment.

FIG. 3 is an exploded perspective view illustrating a configuration of a housing base unit 210 of the document feeding device 20 according to the second exemplary embodiment.

FIG. 4 is a schematic diagram illustrating arrangement of respective rollers of the document feeding device 20 according to the second exemplary embodiment.

FIG. 5 is a diagram illustrating a configuration of a drive unit 220 of the document feeding device 20 according to the second exemplary embodiment.

FIG. 6 is a schematic diagram illustrating a configuration of the document feeding device 20 according to the second exemplary embodiment.

FIG. 7 is an exploded perspective view illustrating a configuration of a document feeding device 30 according to a third exemplary embodiment.

FIG. 8 is a diagram illustrating a configuration of a document feeding device of the related technique.

FIG. 9 is a diagram illustrating a configuration of a drive unit 6 of the related technique.

DESCRIPTION OF EMBODIMENTS

Example 1

FIG. 1 is a schematic diagram illustrating a configuration of a document feeding device 10 according to a first exemplary embodiment, in which the left side illustrates a front of the device, and the right side illustrates a side of the device.

The document feeding device 10 is configured to include a housing base unit 110 and a drive unit 120.

The housing base unit 110 forms a document transportation path, and includes as an output shaft a roller shaft 113 provided with a roller 111 and a driven gear 112.

The drive unit 120 transmits power to the roller shaft 113, and includes a drive gear 121 meshing with the driven gear 112.

The drive gear 121 meshes with the driven gear 112, and has a function of transmitting power to the roller shaft 113 provided with the driven gear 112. Being positioned on an upper side of the driven gear 112, the drive gear 121 meshes with the driven gear 112 when the drive unit 120 is mounted in the housing base unit 110.

In assembling operation, the drive unit 120 is mounted in the housing base unit 110 from an upper side of the housing base unit 110.

According to the document feeding device 10 of the first exemplary embodiment, when the drive unit 120 is mounted in the housing base unit 110, the drive gear 121 is positioned on an upper side of the driven gear 112 to mesh with the driven gear 112. This enables the drive unit 120 to be mounted in the housing base unit 110 from the upper side. As a result, the document feeding device whose components are easily assembled can be provided.

Modified Example

Preferably, when the drive unit 120 is mounted in the housing base unit 110, the drive gear 121 is positioned on an obliquely upper side of the driven gear 112 to mesh with the driven gear 112. Additionally, an angle θ made by a horizontal plane and a line connecting a center of the drive gear 121 to a center of the driven gear 112 in FIG. 1 is preferably equal to or smaller than 45 degrees. Thereby, compared with a case where the drive gear 121 is positioned on the just upper side of the driven gear 112 to mesh with the driven gear 112, for example, collision between teeth of the gears at the time of assembling can be alleviated, and the gears easily mesh with each other.

Although the configuration is made such that the drive unit 120 is mounted in the housing base unit 110 from an upper side in the above description, the same advantageous effect can be obtained even by a configuration in which the mounting is performed in the same manner from a lower side. In other words, the housing base unit 110 may be attached to the drive unit 120 from an upper side. The angle θ in this case is preferably equal to or smaller than 45 degrees from a horizontal plane to a lower side.

Example 2

The document feeding device 20 according to the second exemplary embodiment is configured to include a housing base unit 210 and a drive unit 220, similarly to the document feeding device 10 according to the first exemplary embodiment.

FIG. 2 is a perspective view illustrating external appearance of the document feeding device 20. FIG. 3 is an exploded perspective view illustrating a configuration of the housing base unit 210 of the document feeding device 20. FIG. 4 is a schematic diagram illustrating arrangement of respective rollers when viewing from a roller-axis direction. The arrow in FIG. 4 schematically indicates a path through which a document is transported.

The housing base unit 210 is configured to include roller shafts 213 provided with rollers 211 and driven gears 212. The rollers 211 include a paper feeding roller 201, a separating roller 202, a reading roller 203, and a paper discharging roller 204. The driven gears 212 include driven gears 202a, 203a, and 204a. In other words, the driven gears 202a, 203a, and 204a are provided at end portions of the respective roller shafts provided with the separating roller 202, the reading roller 203, and the paper discharging roller 204.

As for attachment of the respective roller shafts to the housing base unit 210, a general method is used so that the description is omitted here.

The paper feeding roller 201 is arranged at an upper center of the document feeding device 20, and on a lower side of the paper feeding roller 201, the separating roller 202 making a pair with the paper feeding roller 201 is arranged. The paper feeding roller 201 has a function of sending out a document to a document transportation path.

The separating roller 202 has a function of receiving drive of rotation opposite to that of the paper feeding roller 201, and taking off documents one by one from a sheaf of documents. Since this function is a general function, the description is omitted here. Further, a pick roller playing an auxiliary role for the paper feeding roller 201 is adopted in some cases, but the description is omitted here.

It is assumed that a side of inserting a document is an upstream side, and a side of discharging a document is a downstream side.

At least one end of the roller shaft of each of the paper feeding roller 201, the separating roller 202, the reading roller 203, and the paper discharging roller 204 is fixed to the housing base unit 210. In FIG. 3, the roller shafts 213 are drawn on the upper side of the housing base unit 210, but actually, only the paper feeding roller shaft is positioned on the upper side of the housing base unit 201, and the other roller shafts are positioned on the lower side of the housing base unit.

The housing base unit 210 includes a positioning part 214b and a drive-unit fixing screw hole 214c for attaching the drive unit 220. The positioning part 214b and the drive-unit fixing screw hole 214c are each provided at two positions by taking into consideration rotation prevention and vertical positioning, and have a shape corresponding to the drive unit. This makes it possible to precisely mount the drive unit 220 in the housing base unit 210 from the upper side.

The housing base unit 210 forms a guide surface 214a on the downstream side of the paper feeding roller 201, and forms a document transportation path in cooperation with an unillustrated guide surface on the upstream side.

The reading roller 203 is arranged on the downstream side of the transportation path. A new transportation path is formed so as to make a U-turn around the reading roller 203. The transportation path is forced to make the U-turn so that a region on the lower side of the waiting documents before paper feeding can be used as a document discharge space, and the device can be downsized. As illustrated in FIG. 4, at the reading roller 203, one or two pairs of driven rollers 203′ forming a set with the reading roller 203 are arranged on the circumference. The reading roller 203 has a function of transporting a document at the U-turn part by a pressure to and from the driven roller 203′.

At a position where a document reaches the lowest point in the device after completion of the U-turn of the document, a reading unit 215 is arranged. The reading unit 215 includes a reading device 215a and a transparent glass 215b. The transparent glass 215b functions as a guide of the reading unit 215, and a document passes between the reading device 215a and the transparent glass 215b. The reading units 215 may be provided on a front side of and on a rear side of a document, respectively so that both surfaces of a document may be read simultaneously.

On the downstream side of the reading unit 215, the paper discharging roller 204 is arranged. The paper discharging roller 204 has a function of discharging and driving off a document having been read.

On the downstream side of the paper discharging roller 204, a paper output tray 216 is provided.

FIG. 5 is a diagram illustrating a configuration of the drive unit 220. The drive unit 220 is constituted by a motor 222 and a case-shaped form that includes two side plates 280a and 280b as frames. The case-shaped form includes the necessary number of drive gears (gear group) 221, and gear shafts inside. The gear group 221 and the gear shafts are interposed between the both side plates 280a and 280b so that rigidity and shaft precision can be secured. As a result, high accuracy of a read image can be achieved. As a material of the side plates 280a and 280b, sheet metal can be selected to secure the rigidity and the shaft precision.

In the document feeding device illustrated in FIG. 8 and FIG. 9, apart from the above-described problem, when the gears are attached from the horizontal direction to the respective roller shafts, and are fixed by the side plate b of the drive unit 6, it was necessary to slide the side plate b while paying attention so that each gear is not displaced. In addition, a jig for sliding the side plate b was needed. On the contrary, in the document feeding device 20 according to the present exemplary embodiment, the drive unit 220 is made case-shaped. Thereby, the single unit is formed, and the drive unit superior in handling can be provided.

The gear group 221 includes three drive gears (preceding gears) 205, 206, and 207 meshing with the driven gears 202a, 203a, and 204a provided at the respective separating, reading, and discharging roller shafts.

FIG. 6 is a schematic diagram illustrating a configuration of the document feeding device 20, in which the left side of FIG. 6(a) illustrates a device front, and the right side illustrates a side. As illustrated in FIG. 6(a), when the drive unit 220 is mounted in the housing base unit 210, the gear group 221 is positioned on the upper side of the driven gears 212 to mesh with the driven gears 212. In other words, as illustrated in FIGS. 6(b1) to (b3), each of the drive gears 205, 206, and 207 is positioned on the upper side of the corresponding driven gear 212 to mesh with the driven gear 212.

The gear group 221 is preferably positioned on an obliquely upper side of the driven gears 212 to mesh with the driven gears 212 when the driven unit 220 is mounted in the housing base unit 210. Further, in FIGS. 6(b1) to (b3), angles α, β, and γ made by a horizontal plane and lines connecting centers of the gear group 221 (205, 206, and 207) to centers of the driven gears 212 are preferably equal to or smaller than 45 degrees.

Thereby, compared with a case where the gear group 221 (205, 206, and 207) is positioned on the just upper side of the driven gears 212 to mesh with the driven gears 212, for example, collision between teeth of the gears at the time of assembling can be alleviated, and meshing between the gears is facilitated.

A motor 222 has a function as a drive source. When electric power is supplied to the motor 222, the drive unit 220 transmits drive to the gear group 221. The drive is transmitted to the roller shafts 213 via the driven gears 212 meshing with the gear group 221.

According to the document feeding device 20 of the second exemplary embodiment, when the drive unit 220 is mounted in the housing base unit 210, the gear group 221 is positioned on the upper side of the driven gears 212 to mesh with the driven gears 212. Thereby, the drive unit 220 can be mounted in the housing base unit 210 from the upper side. As a result, it is possible to provide the document feeding device whose components are easily assembled.

Example 3

For a configuration that is not particularly described in the following, a document feeding device 30 according to a third exemplary embodiment has the same configuration as the document feeding devices 10 and 20 according to the first and second exemplary embodiments.

FIG. 7 is an exploded perspective view illustrating the configuration of the document feeding device 30.

In the document feeding device 30 according to the present exemplary embodiment, an electromagnetic clutch 323 is provided in a transmission path to a paper feeding roller 301. The electromagnetic clutch 323 is included in the drive unit 320, and is positioned coaxially with a paper feeding roller shaft 301a when the drive unit 320 is mounted in the housing base unit 310. Electromagnetic clutches are illustrated in FIG. 2 and FIG. 5 as well.

The electromagnetic clutch 323 has a function of electrically making on and off action for drive transmission. In the present exemplary embodiment, the electromagnetic clutch 323 is used for controlling drive and stop of the paper feeding roller 301.

At the paper feeding roller shaft 301a, an attachment 317 is provided. An attachment is illustrated in FIG. 2 and FIG. 3 as well. The attachment 317 divides the paper feeding roller shaft 301a into a shaft where the paper feeding roller 301 is provided and a shaft where the electromagnetic clutch 323 is provided. Thereby, while the shaft to which the electromagnetic clutch 323 is attached is kept fixed to the drive unit 320, the shaft where the paper feeding roller 301 is provided can be freely attached and detached. As a result, the paper feeding roller 301 is an independent unit that can be periodically replaced in maintenance or the like. Also in an assembling process, it is possible to incorporate the paper feeding roller 301 alone later, without influencing the housing base unit 310 and the drive unit 320.

According to the paper feeding device 30 of the third exemplary embodiment, the attachment 317 is provided at the paper feeding roller shaft 301a. Thereby, the shaft that is positioned at an upper part of the device and is prone to be an obstacle to assembling, i.e., the shaft where the paper feeding roller 301 is provided can be incorporated alone later. As a result, it becomes possible to mount the drive unit 320 in the housing base unit 310 from an upper side.

Although the exemplary embodiments of the present invention are described above, the present invention is not limited to the above-described exemplary embodiments, and needless to say, includes other modified examples and applied examples without departing from the intention of the present invention.

The invention of the present application claims a priority based on Japanese patent application No. 2013-140579 filed on Jul. 4, 2013, whose entire disclosure is incorporated herein.

INDUSTRIAL APPLICABILITY

The present invention can be applied to a document feeding device such as a printer, a copying machine, or a facsimile machine.

REFERENCE SIGNS LIST

10, 20, 30 document feeding device

110, 210, 310 housing base unit

111, 211 roller

112, 212 driven gear

113, 213 roller shaft

120, 220, 320 drive unit

201, 301 paper feeding roller

202 separating roller

203 reading roller

203′ driven roller

204 paper discharging roller

202a, 203a, 204a driven gear

205, 206, 207 drive gear

214a guide surface

214b positioning part

214c drive-unit fixing screw hole

215 reading unit

215a reading device

215b transparent glass

121 drive gear

221 gear group

222 motor

280a, 280b side plate

301a paper-feeding-roller shaft

317 attachment

323 electromagnetic clutch

1 motor

2 drive transmission system

3 output shaft

4 housing base unit

5 control device

6 drive unit

a, b side plate

Claims

1. A document feeding device comprising a housing base unit and a drive unit, wherein the housing base unit forms a document transportation path, and comprises a roller shaft including a roller and a driven gear, the drive unit transmits power to the roller shaft, and comprises a drive gear meshing with the driven gear, and when the drive unit is mounted in the housing base unit, the drive gear is positioned on an upper or lower side of the driven gear to mesh with the driven gear.

2. The document feeding device according to claim 1, wherein when the drive unit is mounted in the housing base unit, the drive gear is positioned on an obliquely upper or obliquely lower side of the driven gear to mesh with the driven gear.

3. The document feeding device according to claim 1, wherein when the drive unit is mounted in the housing base unit, the drive gear is positioned on an upper or lower side of the driven gear at an angle of 45 degrees or less from an horizontal plane with respect to the driven gear to mesh with the driven gear.

4. The document feeding device according to claim 1, wherein the housing base unit comprises a positioning part and a drive-unit fixing screw hole used for mounting the drive unit, and the positioning part and the drive-unit fixing screw hole have a shape corresponding to the drive unit.

5. The document feeding device according to claim 1, wherein the roller shaft includes a separating roller shaft, a reading roller shaft, and a paper discharging roller shaft, and the drive unit comprises drive gears meshing with driven gears provided at the respective roller shafts.

6. The document feeding device according to claim 1, wherein the drive unit comprises two side plates, and the drive gear is interposed unitedly between the two side plates.

7. The document feeding device according to claim 1, wherein the housing base unit comprises as the roller shaft a paper feeding roller shaft including a paper feeding roller and the driven gear, the drive unit comprises an electromagnetic clutch controlling drive and stop of the paper feeding roller, the electromagnetic clutch is positioned coaxially with the paper feeding roller shaft when the drive unit is mounted in the housing base unit, and an attachment is provided at the paper feeding roller shaft, and divides the paper feeding roller shaft into a shaft where the paper feeding roller is provided and a shaft where the electromagnetic clutch is provided.

8. A method for assembling a document feeding device comprising a housing base unit and a drive unit, wherein the housing base unit forms a document transportation path, and comprises a roller shaft including a roller and a driven gear, the drive unit transmits power to the roller shaft, and comprises a drive gear meshing with the driven gear, when the drive unit is mounted in the housing base unit, the drive gear is positioned on an upper or lower side of the driven gear to mesh with the driven gear, and at the time of the meshing, the drive unit is mounted in the housing base unit from an upper or lower side.

9. The method for assembling the document feeding device according to claim 8, wherein the housing base unit comprises as the roller shaft a paper feeding roller shaft including a paper feeding roller and the driven gear, the drive unit comprises an electromagnetic clutch controlling drive and stop of the paper feeding roller, the electromagnetic clutch is positioned coaxially with the paper feeding roller shaft when the drive unit is mounted in the housing base unit, an attachment is provided at the paper feeding roller shaft, and via the attachment, the paper feeding roller shaft is divided into a shaft where the paper feeding roller is provided and a shaft where the electromagnetic clutch is provided.