JPH1047444A - Power transmission shift device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shift power transmission with a simple structure by always meshing a slide gear with a first or second transmission gear selectively, and switchingly sliding the slide gear by means of a reciprocable motor. SOLUTION: A slide gear 2 slidable on a sliding shaft 1 is, on abutting against a stopper 3 or 4, selectively meshed with a gear 01a of a first transmission system, or a gear 02a of a second transmission system, and also meshed with an output gear Mb normally connected to a driving source M within its sliding range. A worm 5 is fixed to a shaft M'a of a reciprocable motor M' as a sliding source of the gear 2. A worm wheel 6 is slid around a fulcrum of oscillation P accompanied with its rotation. A meshing end of the wheel 6 and its opposite end are connected to an elastic connection body 7 at the fulcrum P. In the case that the slide gear 2 is pressed against the stopper 3 or 4, the elastic connection body 7 is flexed for eliminating a pressurizing load. The driving source M can thus be selectively shifted to the first or second transmission system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission switching device capable of selectively switching power transmission between one drive source and two transmission systems by a small output forward / reverse motor. ,
The present invention mainly relates to an apparatus applied to an image recording apparatus having both a static original reading section and a continuous feeding original reading section.

[0002]

2. Description of the Related Art In an image recording apparatus having both a static original reading section and a continuous feeding original reading section, a driving means for moving a scanning body having a light source and a reflecting mirror is required for reading a static original. In addition, for continuous feeding original reading, a driving unit that drives a feeding unit for original feeding is required. Conventionally, one drive source is provided exclusively for each drive unit.

[0003]

The provision of two drive sources such as motors as in the prior art leads to an increase in cost, so that one drive source is selectively transmitted to each drive means. I want to be able to switch. This is possible because reading a continuously fed document and reading a still document are not performed simultaneously. Conventionally, such a configuration has been attempted, but when a device for power transmission switching is provided, the structure itself is complicated, and the drive source of the device itself has a considerable output. Eventually, the cost becomes high, and the advantage of having one drive source is offset.

[0004]

SUMMARY OF THE INVENTION The present invention provides a power transmission switching device having a low cost and a simple structure to selectively drive two transmission systems by one driving source. Such means are used. First, there is provided one slide gear that can selectively mesh with the gear of the first transmission system or the gear of the second transmission system depending on the sliding direction, and the gear on the drive source side is always meshed with the slide gear. Let me
Means is provided between the slide gear and the motor shaft of the forward / reverse rotation motor to slide the slide gear in one of the sliding directions depending on the rotation direction of the motor shaft.

[0005] In the power transmission switching device having the above-mentioned structure, the means includes a worm fixed to the motor shaft of the forward / reverse rotation motor, a worm wheel that is swingable, and a fulcrum side meshes with the worm. The worm wheel is connected to a fulcrum-side end of the worm wheel, and has an other end connected to the slide gear.

The power transmission switching device having such a configuration is applied to an image recording apparatus having both a static original reading section and a continuous feed original reading section, and drives an optical scanning means for reading a static original. It is used for switching between driving of a document feeding unit for reading a continuously fed document.

[0007]

FIG. 1 is a view showing a basic structure of a power transmission switching device, FIG. 2 is a plan view of a power transmission switching device applied to an image recording apparatus, FIG. 3 is a side view thereof, and FIG. FIG. 5 is an internal side view of a continuously fed original reading state (a state in which the scanning bodies B1 and B2 are at the initial movement positions) in the image reading portion of the recording apparatus. FIG.
FIG. 6 is an internal plan view of the continuously fed original reading state (the state where the scanning bodies B1 and B2 are at the initial movement positions), and FIG. 7 is a stationary original reading state of the same. FIG. 8 is an internal front view of the same (in a state where the scanning bodies B1 and B2 are at the movement end positions), and FIG.

The basic structure of the power transmission switching device shown in FIG. 1 will be described. Stoppers 3 and 4 are mounted and fixed on the sliding shaft 1, and a sliding gear 2 is slidably provided between the stoppers 3 and 4 in the axial direction of the sliding shaft 1. It is fitted outside. The sliding shaft 1 may be fixedly supported, and the slide gear 2 may be rotatable with respect to the sliding shaft 1, or the sliding shaft 1 may be rotatably supported. Alternatively, a configuration in which the slide gear 2 and the slide gear 2 rotate integrally may be used. In the latter case, it is conceivable that the slide gear 2 and the slide shaft 1 are spline-fitted.

A slide gear 2 slidable on a slide shaft 1
When it comes to a position where it comes into contact with the stopper 3, it engages with a transmission gear O1a fixed to the first transmission shaft O1 in the first transmission system. Also, when it comes to a position where it comes into contact with the stopper 4,
A transmission gear O fixed to the second transmission shaft O2 in the second transmission system
2a. As described above, depending on the sliding position, the slide gear 2 is selectively driven by the transmission gear O1a of the first transmission system,
It meshes with the transmission gear O2a of the second transmission system.

The slide gear 2 is provided with the stoppers 3.4
In the sliding range therebetween, it is always meshed with the output gear Mb fixed to the output shaft Ma of the drive source M such as a motor.
Therefore, the slide gear 2 comes into contact with the stopper 3,
When the transmission gear O1a is engaged, power is transmitted from the drive source M to the first transmission system, and when the slide gear 2 abuts against the stopper 4 and is engaged with the transmission gear O2a, the drive is transmitted. Power is transmitted from the source M to the second transmission system.

A forward / reverse rotation motor M 'is provided as a drive source for sliding the slide gear 2. As the forward / reverse motor M ', an inexpensive and small DC motor can be used. A worm 5 is fixed to the motor shaft M'a of the forward / reverse rotation motor M '. The worm 5 is meshed with a (partial) worm wheel 6 which can swing about a swing fulcrum P. The worm 5 is driven by the forward / reverse rotation motor M '.
The worm wheel 6 swings about the swing fulcrum P as the worm rotates. The direction of the swing is determined by the rotation direction of the motor shaft M′a of the forward / reverse rotation motor M ′, that is, the rotation direction of the worm 5.

The end of the worm wheel 6 opposite to the end on the side meshing with the worm 5 is connected to the elastic connecting member 7 at the pivot point P.
(The elastic connector 7 and the worm wheel 6 may be integrally formed), and the other end of the elastic connector 7 is connected to the slide gear 2. With the swing of the worm wheel 6 as described above, the elastic connecting body 7 has its swing-side fulcrum P as a fulcrum, and its connection side end to the slide gear 2 is on the opposite side to the swing direction of the worm wheel 6. Rocks. Thereby, the slide gear 2 is moved to the worm wheel 6.
Is slid in the direction opposite to the direction of the swing.

When the slide gear 2 slides, the stopper 3
Or, when pressing against 4, the pressing load is applied, and if it is worsened, the stoppers 3 and 4 or the slide gear 2 may be damaged. However, even if the elastic gear 7 is pressed against the stopper 3 or 4 and tries to slide toward the stopper 3 or 4 against which the slide gear 2 is pressed, the elastic connecting body 7 bends in a curved shape and absorbs the pressing load. I do. Therefore, such a trouble due to the pushing load does not occur. Thus, the slide gear 2 can be disposed at a predetermined position for transmitting power to the first transmission system or the second transmission system without using expensive members such as limit switches and sensors.

By switching the direction of rotation of the forward / reverse rotation motor M 'in this manner, the direction of sliding of the slide gear 2 is switched, and the drive of the drive source M is selectively performed between the first transmission system and the second transmission system. Can be switched. Since the forward / reverse rotation motor M 'has a small output and needs to be driven only at the time of power transmission switching, it can be used at low cost and for a long time.

Next, an embodiment in which the power transmission switching device to which the above basic configuration is applied is applied to an image recording apparatus having both a stationary original reading section and a continuous feeding original reading section will be described with reference to FIGS. 8 will be described. First, a schematic configuration of the image recording apparatus will be described with reference to FIGS. As shown in FIG. 4 or FIG. 5, the image recording apparatus is a reading section in which a reading case 14 is disposed at an upper portion and a reading apparatus of an optical system is disposed therein. It is possible to read a fed document. Below this is a recording section C for recording on recording paper based on the image information of the document read by the reading device or the image information transmitted electronically.

In the reading section, as shown in FIGS.
On the upper surface of the reading case 14, a stationary original placing surface 15 made of a transparent member such as glass and a continuous original feeding section A are provided. An original such as a book is placed on the stationary original placing surface 15 in a stationary state, and the scanning body is moved below the original (inside the reading case 14) to perform scanning and reading. On the other hand, one or a plurality of originals can be continuously fed to the continuous original feeding section A, and scanning bodies B1 and B2 described below are arranged stationary below the originals and the originals are fed. Thus, scanning reading is performed.

As a member for scanning and reading, first, a lens 21a and a photoelectric converter 21b are provided at the bottom in the reading case 14.
Is fixedly provided.
The scanning body to be moved when reading a static original includes a first scanning body B1 and a second scanning body B2.
Connects the light source 17 and the first reflecting mirror 18 to the second scanning body B2.
Has a second reflecting mirror 19 in the upper part and a third reflecting mirror 20 in the lower part.
Are horizontally arranged in the left and right horizontal directions, respectively.

An outline of a method of reading a document will be described. The light source 17 irradiates the stationary original placing surface 15 or the transparent original reading section 16 disposed at the lowermost part of the continuous original feeding section A, and the image of the original content above the original is read. Is reflected by the first reflecting mirror 18. The image reflected by the first reflecting mirror 18 is projected through a second reflecting mirror 19 and a third reflecting mirror 20 to a lens 21a, and the image content is converted into an electronic signal by a photoelectric converter 21b.

When reading a continuously fed original, as shown in FIGS. 4 and 6, both scanning members B1 and B2 are kept stationary at the initial movement position, and the light source 17 is used to scan the fed original reading surface. The image of the original conveyed thereon is reflected by the first reflecting mirror 18, the second reflecting mirror 19, and the third reflecting mirror 20 to form an image on the lens 21a of the photoelectric conversion unit 21. Things. In this case, the rollers of the continuous document feeding unit A, such as the separation roller 28 and the conveyance roller 29, are driven to rotate to continuously feed the document.

Next, when reading a still original, the light source 1
7 to move and illuminate the entire surface of the original to perform reading,
The first scanning body B1 and the second scanning body B2 must be moved. The first driving pulley 22 and the second driving pulley 23 driven by a motor or the like as the transporting means for the scanning members B1 and B2 are located at the initial position (scanning position of the continuously fed original) in the moving range of the scanning members B1 and B2. ), The two pulleys 22 and 23 are supported on the same shaft, and the driving first pulley 22 has a diameter twice as large as that of the driving second pulley 23. A driven first pulley 24 and a driven second pulley 25 are disposed on the left and right sides of the scanning body B1 and B2 on the moving end side, respectively.
2 and the drive second pulley 23 have the same diameter. Then, the first transport belt 26 is wound between the driving first pulley 22 and the driven first pulley 24 on the same side, and the second transport belt 27 is wound between the driving second pulley 23 and the driven second pulley 25 on the same side. Turning. By rotating the driving first pulley 22 and the driving second pulley 23 which are supported by the same shaft and are integral, the transport speed of the first transport belt 26 is twice that of the second transport belt 27. Becomes

Both end portions of the first scanning member B1 are attached to the left and right first conveyor belts 26, 26, and both end portions of the second scanning member B2 are attached to the left and right second conveyor belts 27, 27, respectively. It is engaged and fixed. Thus, the first conveyor belt 2
6. When the first scanning body B1 and the second scanning body B2 attached to the second and second conveyor belts 27 and 27 are transported and driven, the first scanning body B1 moves at twice the speed of the second scanning body B2. Will be done. When reading a stationary original placed on the stationary original placing surface 2, from the state shown in FIGS. 4 and 6 at the reading position of the continuous feeding original, as shown in FIG. The scanning bodies B1 and B2 are moved. At this time, the first scanning body B1 moves at twice the speed of the second scanning body B2. As a result, the distance (optical path length) of the light L emitted from the light source 17 until it reaches the photoelectric conversion unit 21 is always constant during movement. When the first scanning body B1 and the second scanning body B2 reach the reading end portion as shown in FIG.
It reciprocates to return to the initial state (FIG. 4).

As described above, in the image recording apparatus according to the present embodiment, the reading section is provided with both the stationary original reading section and the continuous feeding original reading section. The reading unit does not function. Therefore,
The driving of the first and second conveyor belts for conveying the scanning bodies B1 and B2 in the stationary original reading unit and the driving of various rollers of the continuous original feeding unit A in the continuous original reading unit are performed by one driving source. In order to selectively enable power transmission, an application example of the power transmission switching device shown in FIG. 1 can be applied.

An application example of the power transmission switching device when applied to this image recording apparatus will be described with reference to FIGS. A drive source M such as an electric motor and a forward / reverse rotation motor M ′
The sliding shaft 1 shown in FIG. 1 is disposed on the outer surface of the reading case 14 and serves as a common driving shaft for the first driving pulley 22 and the second driving pulley 23. It is pivotally supported in the reading case 14 from the outside in a penetrating manner. Outside the reading case 14, a slide gear 2 is slidably and rotatably fitted on the slide shaft 1. The output gear M fixed to the output shaft Ma of the drive source M
b and a gear transmission mechanism G1 that constantly meshes with the slide gear 2 regardless of the sliding of the slide gear 2.
2. G3 is interposed.

The worm wheel 6 and the elastic connecting body 7 shown in FIG. 1 are integrated with a vertical swing supporting shaft 9 corresponding to the swing supporting point P shown in FIG. A pivot 8c formed in the middle of the link 8 is pivotally supported, and one end of the pivot 8c is a (part) worm wheel 8a, which is fixed to the motor shaft M'a of the forward / reverse rotation motor M '. Are engaged. A fork 8e is formed at the other end of the link 8, and a radial ring 2a is interposed in the middle of the slide gear 2 integrally. The link 8 and the slide gear 2 are connected so that the ring 2a is sandwiched by the portion 8e.

A reinforcing rib 8 is provided between the worm wheel portion 8a and the pivotal support portion 8c for the pivot shaft 9.
b is formed and reinforced to form a portion corresponding to the worm wheel 6 shown in FIG.
Such a reinforcing rib is not provided between the fork part 8e and the fork part 8e, and the elastic part 8d having the original elasticity of the link 8 is formed, forming a portion corresponding to the achievement coupling body 7 shown in FIG.
In this way, the link 8 is integrally provided with the functions of both the worm wheel 6 and the elastic connecting body 7 and the forward / reverse rotation motor M ′
Is a means for sliding the slide gear 2 in any one of the sliding directions depending on the rotation direction of.

The transmission gear O1a of the first transmission system in FIG. 1 corresponds to an inner gear 10 fixed to the outer end of the sliding shaft 1.
However, this also has the function of the stopper 3 shown in FIG. That is, when the slide gear 2 slides outward on the slide shaft 1, the outer end of the slide gear 2 and the inner gear 10 eventually mesh with each other, and the inner gear 1
0 is integral with the sliding shaft 1, so that the scanning bodies B1 and B2
The power of the drive source M is transmitted to the slide shaft 1 which is the transport drive shaft of the slide gear 2. However, when the slide gear 2 is meshed with the inner gear 10, The sliding gear 2 shown in FIG. 1 which does not slide has the same function as the state where the sliding gear 2 is in contact with the stopper 3.

On the other hand, a stopper 11 corresponding to the stopper 4 is fixedly mounted around the sliding shaft 1, and when the sliding gear 2 comes into contact with the stopper 11, the sliding gear 2
Stops sliding at this position. Above this, transmission gears 12 and 13 for transmitting various rollers of the continuous document feeder A are supported on the outer surface of the reading case 14 as corresponding to the transmission gear O2a of the second transmission system. At a position where the slide gear 2 abuts the stopper 11, the slide gear 2 and the transmission gear 12 mesh with each other, and the power of the drive source M is transmitted to the various roller drive mechanisms of the continuous document feeding unit A. It becomes. Of course, at this time, the slide gear 2 and the inner gear 10 are separated from each other, and the transmission to the slide shaft 1 is cut off. Further, when the slide gear 2 and the inner gear 10 are engaged, the slide gear 2 and the transmission gear 12 are separated.

[0028]

According to the present invention, a power transmission device capable of selectively transmitting power from one drive source to two transmission systems as described above has the following effects. Is played. First, by configuring as in claim 1, the drive source for switching power transmission is a small output forward / reverse motor such as a DC motor, and only needs to be energized when switching power transmission. Power transmission can be switched by the sliding structure of the sliding gear, and a low-cost and simple member configuration can be achieved.

According to a second aspect of the present invention, there is provided a means for sliding the slide gear in one of the sliding directions according to the rotation direction of the motor shaft of the forward / reverse rotation motor in the first aspect. Can be inexpensively configured by the worm gear mechanism and the elastic coupling body, and when the stopper is provided at a predetermined position in the sliding range of the slide gear by the coupling structure by the elastic coupling body, the slide gear presses against the stopper. In this case, the elastic coupling body absorbs the shock at the time, so that the slide gear for meshing with the first transmission gear or the second transmission gear at low cost and safely without using expensive members such as a detection sensor. Can be positioned.

According to the third aspect of the present invention, by applying the power transmission device having such a configuration, the reading of the continuously fed original and the reading of the stationary original can be performed by the same drive source. It is possible to provide an image recording apparatus which is inexpensive and does not require a complicated member configuration.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic structure of a power transmission switching device.

FIG. 2 is a plan view of a power transmission switching device applied to the image recording apparatus.

FIG. 3 is a side view of the same.

FIG. 4 is an internal side view of a continuously fed original reading state (a state in which scanning bodies B1 and B2 are at initial movement positions) in an image reading portion of the image recording apparatus.

FIG. 5 is an internal side view of the still original reading state (the state in which the scanning bodies B1 and B2 are being moved).

FIG. 6 is also a state of continuously feeding originals (scanning members B1 and B);
FIG. 2 is an internal plan view of a state in which the second position is at a movement initial position.

FIG. 7 is an internal plan view of a still original reading state (a state in which the scanning bodies B1 and B2 are at the movement end positions).

FIG. 8 is an internal front view of the same.

[Explanation of symbols]

 M Drive source Ma Output shaft Mb Output gear M 'Forward / reverse rotation motor M'a Motor shaft O1 First transmission shaft O1a Transmission gear O2 Second transmission shaft O2a Transmission gear P Swing fulcrum A Continuous document feeder B1 First scanning body B2 Second scanning body 1 Sliding shaft 2 Slide gear 3 Stopper 4 Stopper 5 Worm 6 (Partial) Worm wheel 7 Elastic connector 8 Link 8a (Partial) Worm wheel 8b Reinforcement rib 8c Pivot 8d Elastic 8e Fork 9 Swing fulcrum shaft 10 Inner gear 11 Stopper 12 Continuous original feeding transmission gear 13 Continuous original feeding transmission gear 14 Reading case 15 Stationary original placing surface 16 Feed original reading surface 22 Driving first pulley 23 Driving second pulley

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H04N 1/04

Claims (3)

[Claims] 1. A slide gear which can be selectively meshed with a gear of a first transmission system or a gear of a second transmission system depending on a sliding direction, and a gear on a drive source side is provided on the slide gear. And a means for sliding the slide gear in any one of the sliding directions depending on the rotation direction of the motor shaft between the slide gear and the motor shaft of the forward / reverse rotation motor. A power transmission switching device, characterized in that: 2. A power transmission switching device according to claim 1, wherein said worm is fixed to a motor shaft of said forward / reverse rotation motor, and a worm wheel which is swingable and whose opposite fulcrum side meshes with said worm. A power transmission switching device, comprising: an elastic connecting member having one end connected to a fulcrum-side end of the worm wheel and the other end connected to the slide gear. 3. A power transmission switching device according to claim 1, wherein the power transmission switching device is applied to an image recording apparatus having both a static original reading unit and a continuous feeding original reading unit, and drives an optical scanning unit for reading a static original. A power transmission switching device for switching between driving of a document feeding means for reading a continuously fed document.