JPH07125868A - Sheet material carrying device and image forming device - Google Patents

Abstract

PURPOSE:To stabilize the pressure-contact force of carrying rollers, and to prevent the generation of carrying-error such as jam, feeding-error and bias feeding or the like. CONSTITUTION:A sheet material carrying device has a carrying rollers 24, 25 for pinching a recording paper 26 as a sheet material between them to carry it, a fixed guide plate 21 as a first guide member for guiding the carrying passage of the recording paper 26 and fixed to a device main body, and a turning guide plate 22 as a second guide member supported by the device main body freely to be opened/closed. Furthermore, the carrying rollers 24, 25 are supported by the device main body, and a plate spring as a pressure-contact means, which makes the carrying rollers 24, 25 pressure-contact with each other, is provided, and a cam 31 as a switching means for switching the carrying rollers 24, 25 between the pressure-contact condition and the separated condition in couple with the opening/closing of the turning guide plate 22 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material conveying device used in, for example, a copying machine or a facsimile.

[0002]

2. Description of the Related Art In recent years, in an image recording / reading device such as a copying machine or a facsimile, a paper feed cassette can be attached to and detached from the front face in order to improve the paper feed operability and to downsize the device. The paper feed method is becoming the mainstream. With this method, the paper feed path from the paper feed cassette in the device to the main body of the device must be arranged so as to pass through the side surface of the main body of the device. The path length tends to be long.

A means for opening the paper feed path is required for clearing a paper jam (hereinafter referred to as a jam) that occurs in the paper feed path of such an apparatus. For example, a reading system and a recording system as shown in FIG. In a copying machine having a paper feeding system, a method of rotating a guide plate 22 'for guiding a paper feeding path to remove jammed paper is used. In this method, one of the transport rollers 24 ', 25' is supported by the rotating guide plate 22 'to facilitate the jam removal, and the transport rollers 24', 25 'are rotated by the rotation of the guide plate 22'. It is designed to be separated.

[0004]

However, in the above-mentioned conventional sheet material conveying apparatus, the pressure contact force of the conveyance roller is an important factor for stable paper conveyance, and if the pressure contact force is excessive or insufficient, the jam occurs. Otherwise, conveyance failure such as feeding failure or skew feeding will occur.

In the conventional mechanism as described above, the transport roller 2 is used.
The pressure contact forces of 4'and 25 'are the locking position of the guide plate 22' on the rotation side, the shape accuracy of the guide plate 22 'and the guide plate 22'.
Since the positional accuracy of the upper transport rollers 24 'and 25' is affected, it is necessary to increase the accuracy in order to obtain an appropriate pressure contact force, which is difficult to manufacture and also affects the cost.

Further, since the drive is supplied to the rotating side conveying roller from the main body side, for example, from the fixed side conveying roller via a gear or the like, the positional relationship between the opposed conveying rollers is required to be more precise. .

The present invention has been made in order to solve the above-mentioned problems of the prior art. The purpose of the present invention is to stabilize the pressure contact force of the conveying roller and prevent conveyance defects such as jams and non-feeds. An object is to provide a material conveying device.

[0008]

In order to achieve the above object, in the present invention, a conveyance roller for nipping and conveying a sheet material and a conveyance path for the sheet material are fixed to the apparatus main body. In a sheet material conveying device having a first guide member and a second guide member that is openably and closably supported by the device body, the conveying roller is supported by the device body,
It is characterized in that a pressing means for pressing the carrying rollers to each other is provided, and a switching means for switching the carrying roller between the pressed state and the separated state is provided in association with opening and closing of the second guide member.

The switching means may be a cam.

[0010]

In the sheet material conveying apparatus configured as described above, the conveying rollers are supported by the apparatus main body, and the pressure contacting means for pressing the conveying rollers to each other are provided, and in association with opening and closing of the second guide member, Since the switching means for switching the conveying roller between the pressure contact state and the separated state is provided, the conveyance roller can always obtain an appropriate pressure contact force in the pressure contact state regardless of the locking position accuracy and shape accuracy of the guide member as in the conventional case. .

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments.

1 and 2 are a cross-sectional view, a plan view and a side view of a conveyance path guide from a paper feed cassette to a recording system in a multi-stage front paper feed type copying machine, as an embodiment best representing the present invention. , And in FIG. In FIG. 1, a side plate 27, a bearing 28, and a leaf spring 29, which will be described later, are omitted to simplify the description, and these are shown in FIG.

In the figure, reference numerals 1 and 2 denote paper feed cassettes for stacking recording paper bundles 3 and 4 as sheet materials, and reference numerals 5 and 6 denote paper feed rollers for feeding the recording paper bundles 3 and 4 one by one. , 7, 8
Is a separation claw for separating the paper together with the paper feed rollers 5 and 6,
Reference numeral 10 is a spring as a pressurizing means for pressing the bundles of recording papers 3 and 4 against the paper feed rollers 5 and 6.

Reference numeral 21 denotes a fixed guide plate as a first guide member, which is fixed to the main body of the apparatus, and provides a paper feed path from the paper feed cassettes 1 and 2 and the paper feed cassettes located therebelow to a recording system (not shown). I'm guiding. Reference numeral 22 denotes a rotation guide plate as a second guide member, the lower end of which is supported by the main body to be freely rotatable by a hinge, and the upper end of which is provided with a pin 23 for driving a cam 31 described later. 24, 2
Reference numeral 5 denotes a conveyance roller that conveys the recording paper 26 as a sheet material, and is driven in the arrow direction of FIG. 1 to convey the recording paper 26 from the bottom to the top of the drawing. Reference numeral 27 denotes a side plate on which the transport rollers 24 and 25 are supported via bearings 28, and a leaf spring 29 as a pressure contact means for pressing one of the transport rollers is attached. This leaf spring 29 is used to convey rollers 24 and 25.
The pressure contact force of is adjusted to prevent jams and misfeeds. Here, the conveying roller to be pressed is supported so as to be movable in a direction away from the other conveying roller.
Further, the side plate 27 is provided with a cam 31, a link 32, and a link guide 33 described later.

Reference numeral 31 is a cam driven by the movement of the pin 23. One arm of the cam 31 has a U-shaped tip so that the pin 23 engages, and the other arm is provided with a hole. The shaft 32b of the link 32 is fitted to the link 32 so as to be freely rotatable. The link 32 has an arm 32a corresponding to each of the transport rollers 24 and 25, and when the link 32 moves up and down, the arm 32a acts on the shaft of the transport roller so as to separate the roller shafts, and only in the vertical direction in the drawing. It is guided by the link guide 33 so as to be rotated in the direction.

Although omitted in this embodiment, in an actual device, an outer cover is attached to the outer side of the rotation guide plate 22, and a handle provided on the cover enables smooth opening and closing.

FIG. 1 shows a state where the paper is normally conveyed. Here, the link 32 is the transport rollers 24, 2
The conveyance rollers are apart from the axis of No. 5 and are in a pressure contact state, and in this pressure contact state, they are pressed against each other with a constant pressure contact force set by the leaf spring 29, so that stable paper conveyance can be performed. Further, since the conveying rollers are supported by the side plate 27, there is no positional deviation between the conveying rollers 24 and 25 which face each other in the paper conveying direction, and the traveling direction of the paper coincides with the conveying direction of the conveying rollers 24 and 25 and the rotation guide plate. A pin 23 projects from the tip of 22 and is engaged with the U-shaped portion of one arm of the cam 31.

Next, FIG. 4 shows the processing when a jam occurs. When the user recognizes that a jam has occurred, the user opens the rotation guide plate 22 to open the conveyance path. When the rotation guide plate 22 rotates, the cam 31 rotates as the pin 23 moves, and the link 32 is lifted upward in FIG.
Then, the link arm 32a moves the shafts of the transport rollers 24 and 25 to release the pressure contact between the transport rollers 24 and 25, and a gap d is generated between the transport rollers 24 and 25, so that the jammed paper 34 becomes free. When the cam 31 is rotated by the angle α in FIG. 4, the pin 23 is disengaged from the cam 31, so that the user can remove the jammed paper 34 after further rotating the rotation guide plate 22. While the cam 31 is rotating, the contact point between the cam 31 and the link 32 moves because the hole for connecting to the link 32 provided in the cam 31 is elongated, so that the link 3
It is possible to prevent an unnecessary force other than the longitudinal direction from acting on 2. Further, in the state of FIG. 4, the weight of the link 32 acts on the cam 31 to rotate the cam 31, but since the pressing force of the transport roller shaft by the plate spring 29 is applied to the link 32 perpendicularly to the moving direction, the deviation occurs. It never falls.
Further, if the link 32 is provided with a biasing means for applying the upward force in FIG. 1, the link 32 can be prevented from slipping down and a reliable operation can be performed.

Next, when the jam processing is completed, the user closes the rotation guide plate 22. The rotation guide plate 22 rotates to re-engage the pin 23 and the cam 31, the cam 31 rotates to push down the link 32, the link arm 32a is disengaged from the transport roller shaft, and the transport rollers 24 and 25 are in pressure contact. become. At this time, since one of the arms of the cam 31 is lengthened, the pin 23
Is surely engaged with the U-shaped portion of the arm. Further, since the end surface of the link arm 32a forms a slope, when the transport roller shaft is applied to the slope, a force is applied in the direction of pushing down the link by the pressure contact force of the leaf spring 29, and the link arm 32a is reliably transported. It is designed to be off axis.

The user further rotates the rotation guide plate 22 to return it to the state of FIG. 1, and the jam processing is completed. Here, since the rotation guide plate 22 is independent of the transport rollers 24 and 25,
The locking position of the rotation guide plate 22 does not require any particular precision,
Stable transportation can always be performed with a constant pressure contact force.

[0021]

According to the present invention having the above-mentioned structure and operation, the carrying roller is supported by the main body of the apparatus, and the pressing means for pressing the carrying roller to each other is provided, which is interlocked with the opening and closing of the second guide member. Since the switching means for switching the conveying roller to the pressure contact state is provided, a constant pressure contact force can always be obtained without being influenced by the locking position accuracy and the shape accuracy of the guide member as in the conventional case, and jams and non-feeding can be prevented. It is possible to provide a sheet material conveying device capable of preventing conveyance failure such as skewing and performing stable conveyance.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a sheet material conveying device according to an embodiment of the present invention.

FIG. 2 is a plan view showing a sheet material conveying device according to an embodiment of the present invention.

FIG. 3 is a side view showing a sheet material conveying device according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view of essential parts showing a sheet material conveying device according to an embodiment of the present invention.

FIG. 5 is a sectional view showing a conventional sheet material conveying device.

[Explanation of symbols]

 21 Fixed Guide Plate (First Guide Member) 22, 22 'Rotating Guide Plate (Second Guide Member) 23 Pins 24, 24', 25, 25 'Conveyor Roller Pair 29 Leaf Spring (Pressing Contact Means) 31 Cam ( Switching means) 32 links

Claims (3)

[Claims] 1. A conveyance roller that nips and conveys a sheet material, a first guide member that guides a conveyance path of the sheet material and is fixed to the apparatus main body, and a second support member that is supported by the apparatus main body so as to be openable and closable. A sheet material conveying device having a guide member, and a pressing member that supports the conveying roller on the main body of the apparatus and presses the conveying roller against each other, the conveying member being interlocked with opening and closing of the second guide member. A sheet material conveying device, comprising a switching means for switching a roller between a pressed state and a separated state. 2. The sheet material conveying device according to claim 1, wherein the switching means is a cam. 3. An image forming apparatus having the sheet material conveying device according to claim 1.