JPH07110716B2 - Roll paper supply unit of image forming apparatus - Google Patents

Description

The present invention relates to a roll paper supply unit for an image forming apparatus.

[Conventional technology]

Generally, in an image forming apparatus such as a copying machine, in order to supply a sheet (transfer sheet) used for image formation to an image forming position, a cut sheet preliminarily cut into a standard size is attached to the image forming apparatus. There is a means for accommodating the sheets in the sheet feeding cassette and feeding the sheets one by one from the sheet feeding cassette, or manually inserting the cut sheets one by one from the transfer sheet insertion port formed in the main body of the image forming apparatus.

However, in such an image forming apparatus using a cut sheet, when the size of the transfer sheet to be used becomes large, there is a disadvantage that a considerable space is required to store the transfer sheet.

Therefore, conventionally, roll paper wound in a roll shape is set in a dedicated roll paper supply unit, precut to a desired size by this roll paper supply unit, and the cut transfer paper is inserted into the transfer paper insertion port. From the image forming apparatus main body.

However, in the case of such a configuration, the roll paper must be cut in advance in the roll paper supply unit, and then the image forming operation must be performed, which is troublesome and inefficient.

In order to eliminate such inconvenience, a roll paper supply unit is integrally incorporated in the image forming apparatus main body, and when the roll paper supply mode is selected as the paper feed mode of the image forming apparatus, the roll paper supply unit is Although it is possible to adopt a structure of supplying transfer paper, in this case, an image forming apparatus having a special and complicated structure must be newly manufactured, which results in high cost. Further, there is an inconvenience that a user who owns an image forming apparatus that does not have a roll paper supply unit built therein must newly purchase an image forming apparatus that incorporates the roll paper supply unit.

Therefore, as a solution to the above-mentioned problem, the applicant of the present invention has proposed that, in Japanese Patent Application No. 2-14486 (filed on January 23, 1990), an image forming apparatus body having an image forming unit is A roll paper supply unit equipped with roll paper, roll paper supply means for feeding the roll paper, and cutting means for cutting the roll paper fed out to a predetermined length is detachably mountable, and a cut paper supply mode is provided. By making it possible to select the roll paper supply mode in addition to the conventional image forming apparatus, it is possible to use not only cut paper but also roll paper as transfer paper easily at low cost. I have applied for an image forming device.

By the way, in the image forming apparatus according to the above-mentioned prior application, a unit frame of a unit main body including roll paper, roll paper supply means for feeding the roll paper, and cutting means for cutting the fed roll paper into a predetermined length. Going up and down
This is done by driving a drive mechanism composed of chains and sprockets with a motor.

[Problems to be Solved by the Invention]

However, in the roll paper supply unit having the above configuration, since the motor and the drive mechanism are provided, the mechanism for moving the roll paper supply unit up and down and holding the roll paper supply unit becomes large, and the configuration itself of the unit becomes large and the unit itself becomes large. There is a problem that a control system for raising or lowering the main body to a predetermined position is required.

On the other hand, it is conceivable to hold the unit body by using a coil spring. By this means, it is possible to raise and lower the unit body by human power, but when the weight of the unit body becomes large (for example, about 50 kg), the diameter and width dimension of the winding spring increase,
In this case as well, the mechanism for raising and lowering the unit and holding it becomes large, and the configuration itself of the unit also becomes large.

The present invention has been made in consideration of the above matters, and an object thereof is to easily raise and lower the unit main body by human power and to provide a roll paper supply unit of an image forming apparatus having a compact overall configuration. To provide.

[Means for Solving the Problems]

In order to achieve the above object, the roll paper supply unit of the image forming apparatus according to the present invention includes a guide member in the up-down direction of a unit frame detachably connected to the image forming apparatus main body having an image forming unit. The unit main body that moves up and down along the guide member is provided with roll paper, roll paper supply means for feeding the roll paper, and cutting means for cutting the fed roll paper to a predetermined length. It is a symmetrical position in the left-right direction of the main body, and
It is characterized in that a holding means for biasing and holding the unit body in a vertically movable manner is provided in an inclined state between the bottom portion of the unit body and the bottom frame of the unit frame.

[Action]

According to the present invention, the unit main body can be moved in the vertical direction, and for example, the roll paper supply mode can be selected in addition to the cut paper supply mode. Further, since the holding means for biasing and holding the unit main body so as to be lifted up and down is provided in an inclined state, the stroke of the holding means can be small,
Therefore, the mechanism for raising and lowering the unit main body and holding the unit main body becomes compact, so that the entire roll paper supply unit can be downsized.

Then, the unit main body can be raised and lowered by applying a slight force upwards or downwards to this, and in the raised state, the biasing holding force of the holding means acts on the unit main body greatly. Further, in the lowered state, the bias holding force acts on the unit main body in a small amount. Therefore, in any case, the unit body is stably held by the biasing holding force of the holding means.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

1 and 2 show the overall structure of an electrostatic photocopier as an example of an image forming apparatus. The copying machine main body (image forming apparatus main body) 1 is mounted on a moving deck 2 and the roll paper 3 is copied. A roll paper supply unit 5 for discharging to a manual paper feed port 4 of the machine body 1 is detachably connected to the copier body 1 via a connecting member 6.

The copying machine main body 1 is configured as follows. That is, the reciprocating means 8 for reciprocating the document with respect to the exposure device 7 is provided on the upper part of the device case 1A, and the large paper feeding cassette 9 is provided on the lower part of the device case 1A so as to be drawn out to the roll paper supply unit 5 side. .

The photoconductor 10 is provided inside the device case 1A so as to rotate in the arrow L direction, and the main charging device is provided around the photoconductor 10.
11, exposure device 7, developing device 12, transfer device 13, separation device 1
4, the cleaning device 15 is installed in this order,
The image forming unit 16 is formed by these members.

Further, a sheet passing guide 17 is provided from the supply section of the sheet feeding cassette 9 to the manual sheet feeding port 4, and a sheet feeding conveying path 18 is provided from the manual sheet feeding port 4 to the transfer device 13.
In this paper feed transport path 18, there is provided a transport roller pair 19 as a transport means for transporting the transfer paper from the manual paper feed port 4 direction or the supply unit direction of the paper feed cassette 8 toward the transfer device 13, A registration roller pair 20 is provided between the conveyance roller pair 19 and the transfer device 13. 21 is a fixing device for fixing the transfer paper after separation / fixing.
A sheet discharge passage 22 is formed between the sheet discharge path 14 and 14, and a sheet discharge roller pair 23 is provided on the downstream side thereof. Reference numeral 24 is a document supply passage, 25 is a document end detecting device, and 26 is a document reversing device.

The moving deck 2 has wheels 27 at the bottom thereof, a transfer paper stock portion 28 is provided inside the movable deck 2 in a state where the transfer paper stock portion 28 is inclined so as to be higher toward the front side, and a bending guide member 29 is detachably attached below the transfer paper stock portion 28. It is provided in.

The roll paper supply unit 5 is configured as follows. That is, the screw shafts are provided at the four corners on the lower side of the bottom frame 30.
Wheels 32 are screwed through 31 and vertical frames 33 are erected on both left and right sides of the bottom frame 30, and vertically extending guide members 34 are provided at the front and rear parts of the vertical frame 33 to adjust movement and level. While constituting a unit frame 35 that can be freely
Rollers 36 to be rolled along the guide member 34 are provided in the upper and lower parts of the unit main body 37, and a gas spring 38 as a holding means for urging and holding the unit main body 37 in a vertically movable manner is provided with a bottom frame 30. It is provided on both left and right sides over the unit main body 37. The gas spring 38 is a cylinder
39, a rod 40, and a gas enclosed in the cylinder 39 at a predetermined pressure so as to urge the rod 40 in a direction to extend the rod 40. Yes, and the unit body 37
Between the bottom 37A of the unit frame and the bottom frame 30 of the unit frame 35,
The roll paper supply unit 5 is provided so as to be inclined toward the front side. 41 and 42 are mounting parts.

Reference numeral 43 denotes a roll paper loading unit formed on the lower side of the unit main body 37, and extends from the paper feeding unit above the roll paper loading unit 43 to the manual paper feeding port 4 of the copying machine main body 1 In the middle of the path, a pair of paper feed rollers 45 serving as a roll paper supply means.
A feed switch 46 for detecting the presence or absence of the leading edge of the roll paper 3, a leading edge holding member 47 for holding the leading edge of the roll paper 3, and a cut for cutting the roll paper 3 to a prescribed length at a prescribed timing. Means 48, a pair of discharge rollers 49, and a discharge switch 50 are provided. A rotation amount detection device 51 detects the number of rotations of the paper feed roller pair 41, and is configured to output a pulse signal in accordance with the rotation of the paper feed roller pair 45. Further, reference numeral 52 is a rotation detecting device for detecting the rotation of the roll paper 3, which is configured to output a pulse signal only when the roll paper 3 rotates.

Further, a paper discharge guide 53 is obliquely provided on the upper part of the cutting means 48, and a cover 54 which also serves as a paper discharge guide surface is provided on the front side of the unit corresponding to the roll paper loading section 43 so as to be openable and closable. The cover 54 holds the roller 45A on the driven side of the paper feed roller pair 45, and the guide plate 55 which forms a paper discharge path by the cover 54 and the cut paper discharged through the paper discharge path are moved to the moving deck. A guide member 56 for guiding to the 2 side is provided. Incidentally, 57 is a plate-shaped guide member connected to the bending guide member 29 provided on the movable deck 2,
Reference numeral 58 is a grip bar horizontally provided above the front of the unit main body 37.

Control of each part of the electrostatic photocopier is performed by a control device (not shown).

In order to connect the roll paper supply unit 5 to the copying machine main body 1 in the electrostatographic copying machine having the above structure, first,
The unit frame 35 is moved to a predetermined position on the front side of the copying machine main body 1, the unit frame 35 is connected to the copying machine main body 1 via the connecting member 6, and then the grip body 58 is grasped to hold the unit main body 37.
Lift up. In the state where the unit main body 37 is raised, since the inclination angle α of the gas spring 38 with respect to the direction of gravity, that is, the vertical direction is small, the upward biasing force of the gas spring 38 exerts a great effect on the unit main body 37. To do. When the unit body 37 is raised to a position higher than the predetermined position, the upward biasing force of the gas spring 38 becomes larger than the gravity due to the weight of the unit body 37. Therefore, when the unit body 37 is at the uppermost position, the gas spring in the state in which the rod 40 is most extended
Since it is stably held by 38, its descending is prevented without adding special locking means. Then, in this state, the unit main body 37 is fixed by a lock device (not shown), so that the roll paper supply unit can be set at a predetermined paper feed position.

In this state, by turning on the start key of the operation / display section (not shown), the pair of paper feed rollers 45 rotate and the roll paper 3
Can be supplied to the copying machine main body 1 side.

By the way, when the paper feed cassette 9 is pulled out to the roll paper supply unit 5 side to replenish the paper feed cassette 9 with paper, or when a jam process in the copying machine body 1 is performed, the unit is It is necessary to push down the main body 37 to the lower position so as not to interfere with those operations, but at this time, by releasing the locking device and applying downward force to the grip bar 58, the unit main body 37
Can be lowered. At the time of this lowering, the upward biasing force of the gas spring 38 acts, but the biasing force becomes smaller as the inclination angle α gradually increases. Then, when the unit main body 37 is lowered to a position lower than the predetermined position, the relationship between the gravity due to the own weight of the unit main body 37 and the upward biasing force of the gas spring 38 is reversed and the gravity is applied. It is larger than the force holding power. Therefore, when the unit main body 37 is located at the lowermost position, the rod 40 is stably held by the gas spring 38 in the most contracted state, so that the unit body 37 is prevented from rising even if no special locking means is added.

Then, according to the roll paper supply unit 5 configured as described above,
Since the gas spring 38 for holding the unit main body 37 in a vertically movable manner is obliquely provided, the stroke of the gas spring 38 becomes shorter than that in the case where the gas spring 38 is provided in a vertical state, and therefore the unit main body 37 The mechanism for raising and lowering and holding it is compact, and a control system for raising and lowering the unit main body 37 is completely unnecessary.

The gas springs 38 may be provided at symmetrical positions in the left-right direction of the unit main body 37. Therefore, the gas springs 38 may be provided so as to incline toward the rear surface side of the roll paper supply unit 5, or the roll paper supply unit 5 may be inclined. It may be provided in a "H" shape when viewed from the front side.

The electrostatic photocopier can be used in a cut paper supply mode for supplying cut paper without using the roll paper supply unit 5, but in that case, cut paper is supplied from the manual paper feed port 4 or The cut paper may be supplied from the paper feed cassette 9, and in this case, the roll paper supply unit 5 does not have to be separated from the copying machine main body 1. The paper feed mode is set by a mode selection key on the operation / display unit (not shown).

The present invention can be applied not only to the electrostatographic copying machine in the above-described embodiment but also to an image forming apparatus such as a printer.

〔The invention's effect〕

As described above, according to the present invention, not only cassette paper but also roll paper can be supplied to the image forming apparatus. Then, the unit main body can be raised and lowered by applying a slight force upwards or downwards to this, and in the raised state, the biasing holding force of the holding means acts on the unit main body greatly. Further, in the lowered state, the bias holding force acts on the unit main body in a small amount. Therefore, in any case, the unit body is stably held by the biasing holding force of the holding means. Further, since the mechanism for raising and lowering the unit main body and holding the unit main body is compact and a control system or the like is not required, the roll paper supply unit can be further downsized, and in turn, the image forming apparatus can be downsized.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, and FIG. 1 is a diagram showing the overall configuration of an electrostatic photocopier as an example of an image forming apparatus equipped with a roll paper supply unit according to the present invention. 2 is a perspective view thereof, and FIGS. 3 (A) and 3 (B) are operation explanatory views of the roll paper supply unit. 1 ... Copier main body (image forming apparatus main body), 3 ... roll paper, 5 ... roll paper supply unit, 16 ... image forming unit, 30 ...
… Bottom frame, 34 …… Guide member, 35 …… Unit frame,
37 …… Unit body, 38 …… Holding means.

Claims (1)

[Claims] 1. A guide member is provided in a vertical direction of a unit frame detachably connected to an image forming apparatus main body having an image forming unit, and a roll paper is attached to the unit main body which moves up and down along the guide member. And a roll paper feeding means for feeding the roll paper and a cutting means for cutting the fed roll paper to a predetermined length, and at a symmetrical position in the left-right direction of the unit body, A roll paper supply unit for an image forming apparatus, characterized in that a holding means for biasing and holding the unit main body is provided in an inclined state between the bottom portion and the bottom frame of the unit frame.