JP2001294360A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device capable of favorably cutting sheets, and elongating the service lie of a cutter blade without generating a problem in carrying of the sheets. SOLUTION: In platens 3a and 3b supporting a sheet 2 when the sheet 2 is carried, printed and cut, a recessed groove part 3c for running of cutter blade 13 is formed. On the downstream side of the recessed groove part 3c, a vertically movable slide members slide 14 is disposed, and an upper surface of the slide member 14 when sheet 2 is carried and printed is set at a roughly similar height to the upstream side platen 3a. On a lower surface of the slide member 14, plural springs 17 to energize a medium pressing member 12 in such a direction as to be pushed up are provided. When the cutter blade 13 cuts the sheet 2, the slide member 14 and the medium pressing member 12 cooperate with each other to hold the sheet 2 at a position below the upstream side platen 3a by pressing force of the medium pressing member 12. The cutter bade 13 and the sheet 2 thus form a proper sheet cutting angle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing medium pulled out of a state wound, for example, in a cylindrical shape.
The present invention relates to an image forming apparatus provided with a cutting unit for cutting a printing medium after image formation by an arbitrary method.

[0002]

2. Description of the Related Art An example of an ink jet printer as an image forming apparatus according to the prior art will be described with reference to the drawings. FIGS. 4, 5 and 6 are schematic diagrams showing an example of an ink jet printer according to the related art. The "paper" referred to below indicates a print-receiving medium on which the ink jet printer performs printing. Indicates plain paper, coated paper, second original drawing paper, glossy paper, glossy film, back print film, clear film, plastic film, peram paper, cloth, and the like. In addition, although there are various sizes, here, the above-described print-receiving media are collectively referred to as “paper” regardless of the material and size.

As shown in FIGS. 4 to 6, the rear side of the main body of the ink jet printer 31 (the rear side and the right side in the figure).
Is mounted with a sheet of paper 32 wound in a cylindrical shape. The paper 32 is transported intermittently by a transport roller 34.
And a pinch roller 35 that is driven in rotation by being pressed against the transport roller 34 to apply a transport force, and the negative pressure generated by a suction fan 38 disposed in a lower area of the platen 33 causes It is held in a state of sticking to. The pinch roller 35
Is pressed against the transport roller 34 via a rotatable “<”-shaped pinch roller arm 36 by the urging force of a pinch roller spring 37.

The sheet 32 conveyed to a position immediately below the print head 40 by the conveyance roller 34 and the pinch roller 35 temporarily stops at that position. At this time, paper 3
The print head 40 attached to the carriage 39 that scans in the direction (transverse direction) transverse to the transport direction 2 discharges ink from the tip thereof by an arbitrary method such as heat or pressure, and discharges ink by a width corresponding to the horizontal image forming width. Is performed to print one line of the entire image. Thereafter, the transport roller 34 and the pinch roller 35 rotate again by a predetermined amount, and stop when the unprinted area of the paper 32 has been transported directly below the print head 40. The inkjet printer 31 forms a predetermined image by repeating the above-described main scanning in the horizontal direction of the print head 40 and the intermittent sub-scanning feeding in the vertical direction between the transport roller 34 and the pinch roller 35 as described above.

The above-described ink jet printer 31
In, for example, the paper used for image formation is A0
In the case of a very large size, such as the size, preparing multiple sheets of paper cut to the standard size is not practical due to problems such as the installation area and is not realistic. The paper 32 continuously wound into a cylindrical shape as described above is set on the inkjet printer 31. In response to this, a paper cutting cutter device 41 that runs in a direction (lateral direction) parallel to the scanning line of the print head 40 is provided.

The cutter device 41 is, for example, incorporated in a carriage 39, as shown in FIG. 5, for example, and usually, at the time of printing, is located at an end position in the main scanning direction where the cutter blade 43 cannot cut the paper. The sheet is retracted (see FIG. 4), and has a structure in which the cutter blade 43 appears in the sheet conveying area only when cutting the sheet.

[0007] The cutter device 41 in such a sheet cutting means is such that the cutter blade 43 runs straight from the end of the sheet 32 in a direction (lateral direction) crossing the sheet conveying direction. However, a structure is employed in which the cutter blade 43 is inclined with respect to the sheet 32 so that the cutter blade 43 can perform cutting with good quality.

[0008] More specifically, as shown in FIG.
The cutter blade 43 itself is disposed so as to be slightly inclined with respect to the vertical direction, and the upper portion of the cutter blade 43 is attached so as to be inclined toward the upstream side in the transport direction of the paper 32. ing. At this time, the lower end of the cutter blade 43 is
3 is housed in a concave groove portion 33c.

Further, the platen 33b on the downstream side in the transport direction of the paper 32 is arranged to be lower by the step H than the platen 33a on the upstream side of the paper cutting section, which is the traveling portion of the cutter blade 43. Have been. And
A medium pressing member 42 that presses the sheet 32 against the platen 33 is disposed downstream of the sheet cutting unit to prevent the sheet 32 from floating due to the provision of the step H.

By providing the step H as described above, the sheet 32 in the sheet cutting section is conveyed obliquely downward, and the image forming surface of the sheet 32 and the travel of the cutter blade 43 are correspondingly increased. The track surface is further inclined, and the paper cutting angle α is set to an acute angle in combination with the above-described inclined arrangement of the cutter blade 43. With the configuration in which the cutter blade 43 and the paper 32 are arranged obliquely in this way, the burrs on the cut surface are reduced,
It is clear from design experience that the cutability of the paper 32 can be improved.

However, when the step H is formed on the platen 33 as described above, as shown in FIG. 8, the already cut sheet 32a is caused by static electricity generated between the sheet 32a and the downstream platen 33b. Downstream platen 3
When sticking to the 3b side, the following problems occur. The electrostatic attraction is performed when the sheet 32 to be conveyed is discharged in a state in which the sheet 32 is in close contact with the downstream platen 33b.
b, the rear end portion of the sheet 32 adhered to the downstream platen 33b side due to such electrostatic attraction, the concave portion formed by the step H of the platen 33. It falls into the groove 33c.

As described above, the previously cut paper 32 is
When the rear end of the sheet 32 falls into the concave groove 33c in the state of the electrostatic suction described above, the front end of the sheet 32 sent next pushes the rear end of the previous sheet 32. And the subsequent sheet 32 is rubbed so as to overlap the surface of the preceding sheet 32. At this time, if the ink of the image printed on the previous paper 32a has not been completely dried yet, the previous paper 32a
When the next sheet of paper 32 rubs the image forming surface, a serious problem such as image rubbing may occur.

The simplest way to solve such a problem is to set the height of the upstream portion and the downstream portion of the platen 33 at the same level with the concave groove 33c as the boundary. In this case, the paper cutting angle α as described above cannot be secured at an acute angle. That is, when the height of the paper 32 before and after the paper cutting is the same, in order to secure the acute paper cutting angle α, the cutter blade 43 is required.
Needs to be tilted to a state close to horizontal. When the cutter blade 43 is tilted to a state close to horizontal, the cutter blade 43 protrudes in the groove width direction, and the groove width dimension of the concave groove portion 33c on which the cutter blade 43 travels must be greatly increased. And the paper 32 is being transported,
The possibility that the leading end of the sheet 32 falls into the groove 33c is further increased.

When the medium pressing member 42 presses the sheet 32 at the same height, the cutter blade 43
However, the paper 32 is always cut at the same position in the vertical direction, and as a result, the vertical movement accompanying the cutting of the cutter blade 43 is lost, and the same position in the vertical direction of the cutter blade 43 is worn intensively. And the life of the blade is shortened. For this reason, the time required for replacing the cutter blade 43 increases, and the running cost increases. This is an undesirable situation from the viewpoint of commercial value of the inkjet printer 31.

In such a situation, the cutter blade 43
As a means for extending the life of the paper cutter, a means for changing the cutting position of the cutter blade 43 in the vertical direction so as to cause the so-called cutter blade 43 to perform a reciprocating operation is conventionally known. For example, the above-described inkjet printer 31
As means for performing the reciprocating operation, a platen is formed with a slope inclined toward the paper width direction which is the cutting direction of the paper 32, and the cutter blade 43 is formed along the slope.
There is a configuration in which the cutter blade 43 is moved up and down by reciprocating the cutter blade.

[0016]

However, since such an inclined surface on the platen is formed by a dent or a bulge formed in the platen 33b, it is likely that the sheet 32 is caught when the sheet 32 is conveyed. Easy to be,
It is not preferable as the shape of the paper transport path.

Accordingly, the present invention provides a method for maintaining a good cutting state of a sheet without impeding the sheet conveyance.
An object of the present invention is to provide an image forming apparatus capable of extending the life of a cutter blade.

[0018]

In order to achieve the above object, according to the first aspect of the present invention, the printing medium is cut by traveling in a direction transverse to the conveying direction of the printing medium. A cutter blade, a medium pressing member disposed at least downstream of the direction of conveyance of the print medium with respect to the cutter blade, and traveling with the cutter blade while pressing the print medium toward the medium supporting surface; A groove provided on the medium support surface so as to extend in a traveling direction of the cutter blade and accommodate a tip portion of the cutter blade, wherein the groove is downstream from the groove in the transport direction of the print-receiving medium. In the image forming apparatus, the medium supporting surface on the side is arranged via a step so as to be lower than the medium supporting surface on the upstream side, and extends in the running direction of the cutter blade and the medium pressing member, and A slide member for sandwiching the print-receiving medium between the medium support member and the slide member, the slide member being reciprocally mounted in a direction of a step on the medium support surface, and the slide member being disposed on the medium pressing member side. Elastic biasing means for pressing the slide member elastically by the pressing force of the medium pressing member is provided, and the elastic biasing means is provided in the running direction of the cutter blade and the medium pressing member. Along, the amount of sinking of the slide member by the medium pressing member is made different.

Further, according to the second aspect of the present invention, when the slide member is moved upward by the elastic urging means, the upper surface of the slide member is positioned on the upstream side. A restricting means is provided for restricting a rise above the medium supporting surface.

According to a third aspect of the present invention, the slide member according to the second aspect is disposed along the traveling path of the medium pressing member so as to face the medium pressing member with the print medium interposed therebetween. Made of a long member.

According to a fourth aspect of the present invention, the elastic biasing means provided on the slide member according to the third aspect comprises a plurality of spring members having different displacements with respect to the same load in the reciprocating direction. The plurality of spring members are arranged in order of decreasing displacement along the traveling direction of the cutter blade and the medium pressing member.

According to the first aspect of the present invention, when the cutter blade travels through the concave portion of the medium support surface to cut the print-receiving medium, the slide member moves the medium support surface. Sinks in a direction perpendicular to the direction, thereby forming a step between the medium supporting surface and the slide member, so that the print target medium is inclined with respect to the upstream side medium supporting surface in the concave groove portion. As a result, a sharp paper cutting angle with good cutability is formed between the cutter blade and the print-receiving medium.

Further, according to the second aspect of the present invention,
The position of the upper surface of the slide member when the print medium is not cut is regulated by the regulating means so as not to rise above the medium support surface on the upstream side. It does not interfere with the transport of the media.

Further, according to the third aspect of the present invention, since the slide member is arranged corresponding to the traveling path of the slide member so as to face the medium pressing member, the slide member is cut when the print medium is cut. The slide member sinks from the medium support surface only when the medium pressing member presses the printing medium.

According to the fourth aspect of the present invention, since the slide member does not sink evenly with respect to the medium supporting surface, the cutting position of the cutter blade with respect to the medium to be printed is moved.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an image forming apparatus according to the present invention will be described in detail with reference to the drawings. In addition,
The image forming apparatus according to the present invention is not limited to the embodiment described below, and can be applied to various image forming apparatuses by appropriately designing and changing each element without departing from the gist of the image forming apparatus. It can respond.

FIG. 1 is a sectional view of a main part of an ink jet printer as an embodiment of the image forming apparatus according to the present invention, and FIG. 2 is an enlarged view of a main part of the ink jet printer shown in FIG.

The ink jet printer 1 shown in FIG.
Basically, it has a configuration similar to that of the ink jet printer 31 already described in the above-mentioned prior art, and the corresponding members are denoted by reference numerals obtained by subtracting the reference numeral by 30. .

The apparatus according to the present embodiment is also provided with a cutter device 11 for separating a portion of the sheet 2a, which is a printing medium on which an image has been formed, from the sheet 2 on which an image has not yet been formed. . The cutter device 11 is incorporated in the carriage 9, and has a cutter blade 13 that travels in a direction transverse to the transport direction of the sheet 2 and cuts the sheet 2 as the carriage 9 scans. I have. In the vicinity of the cutter blade 13 in the cutter device 11, a sled-shaped medium pressing member 12 that travels while pressing the paper 2 with the travel of the cutter blade 13 is disposed.

Further, when the sheet 2 is conveyed, printed, and cut, a platen 3a, 3b serving as a medium supporting surface for supporting the sheet 2 has a cutter blade 1 running in the sheet width direction.
3 is formed to extend in the same direction. The platen 3 provided on the upstream side in the transport direction of the paper 2 with the groove 3c as a boundary.
a is disposed so as to be slightly higher than the downstream platen 3b, and a step H (see FIG. 2) is formed between the upstream platen 3a and the downstream platen 3b. I have.

On the other hand, as shown in FIG. 2, a slide member 14 composed of an elongated prismatic member is disposed immediately below the medium pressing member 12 on the downstream side of the concave groove 3c. The slide member 14 is arranged so that its longitudinal direction extends in the paper width direction crossing the paper 2, and when the cutter blade 13 travels in the groove 3 c to cut the paper 2, The sheet 2 is held up and down in cooperation with the medium pressing member 12.

That is, a plurality of coil-shaped springs (elastic biasing means) 17 are arranged on the lower surface side of the slide member 14 at appropriate intervals in the longitudinal direction so as to abut against each other in a compressed state. The slide member 14 is urged in a direction to push up the medium pressing member 12 on the upper side. Thus, the slide member 14 cooperates with the medium pressing member 12 to sandwich the sheet 2 up and down. At this time, it is preferable that the material constituting the slide member 14 is not a rigid material but a material having a suitable elasticity and a high toughness, such as PC or ABS.

A plurality of U-shaped regulating hooks 15, 15,... Are provided at the lower edge of the slide member 14 so as to hang down, and an end surface of the downstream platen 3b is provided. In addition, small-diameter cylindrical stopper pins 16, 1 are provided at positions corresponding to the respective restriction hooks 15, respectively.
Are provided so as to protrude toward the upstream side in the paper transport direction. Then, the U
Each of the stoppers 16 is disposed so as to be inserted in a loosely fitted state in the inside opening of the character shape, whereby the vertical movement width of the slide member 14 is regulated. That is, when the slide member 14 is slid upward, the lower end of each restriction hook 15 contacts the stopper pin 16, and the upper surface of the slide member 14 at the restriction position is restricted. Are arranged at a position substantially the same as or slightly lower than the upstream platen 3a so that they do not protrude above the upstream platen 3a.

As described above, the slide member 14 is disposed so that its longitudinal direction is oriented in the lateral direction in response to the lateral movement of the medium pressing member 12, and the position immediately above the slide member 14 is determined. The medium pressing member 12 is arranged so as to be contactable, and an area (travel path) for pressing the paper 2 is formed between the slide member 14 and the medium pressing member 12. Then, when the sheet 2 is cut, when the medium pressing member 12 presses the sheet 2 downward, the slide member 14 is pressed by the lower pressing force of the medium pressing member 12 so that the upstream platen is pressed. It is configured to sink from the upper surface of 3a.

At this time, as shown in FIGS. 2 and 3, the upper ends of the springs 17 are in pressure contact with the lower surface of the slide member 14, and the lower ends of the other ends of the springs 17 are pressed. The portion is mounted on a spring mounting surface of a spring holding table 18 disposed inside the device directly below the slide member 14. At this time, the upper surface, which is the spring mounting surface, of the spring holder 18 is formed as an inclined surface having a rising gradient in a direction from C1 to C2 in FIG. 3 which is the running direction of the cutter blade 13 and the medium pressing member 12. It is formed on an inclined surface that gradually rises in the same direction.

The length of each of the springs 17 is gradually reduced by an amount corresponding to the rising gradient of the spring holding table 18, whereby each of the springs 17 is displaced by the same load (free). Length and compression length) are set to be different from each other, and the cutter blade 13 and the medium pressing member 1
2 travels when cutting the paper 2 (from C1 to C in FIG. 3).
In 2), the arrangement relationship of the springs 17 is set so that the displacement amount gradually decreases. For this reason, when cutting the paper 2, the amount of sinking of the slide member 14, that is, the step is reduced so as to follow the inclination of the spring holder 18.

That is, when the slide member 14 is not subjected to the pressing force from the medium pressing member 12, the upper surface of the slide member 14 is maintained substantially horizontally along the horizontal direction, Although the height is substantially the same as the upper surface of the upstream platen 3a, when the sheet is cut, the pressing force of the medium pressing member 12 is applied to the slide member 14 via the sheet 2 so that the slide member 1
The upper surface of the medium press member 4 sinks with respect to the upper surface of the upstream platen 3a, and the amount of sink at that time gradually decreases as the medium pressing member 12 travels.

In the ink jet printer 1 configured as described above, first, as shown in FIG. 3, when the cutter blade 13 is at the position C1 where cutting of the paper 2 is started, the slide member 14 The sheet 12 is pushed down together with the sheet 2 by the pressing force for pressing the sheet 2, and sinks relatively greatly from the wavy line position to the solid line position in FIG. In this configuration, the upward pressing force of the spring 17 is set to be relatively weaker than the downward pressing force of the medium pressing member 12 against the slide member 14 provided immediately below the medium pressing member 12. That's why. As a result, the upper surface of the slide member 14 sinks downward to a position lower than the upper surface of the upstream platen 3a,
A step is formed between the upper surface of the upstream platen 3a and the upper surface of the slide member 14.

On the other hand, when the cutter blade 13 advances in the direction from the position C1 to the position C2 in FIG. 3, according to the inclination of the spring holding base 18 having an ascending gradient, the above-mentioned step is lowered. The height will decrease. That is, the trajectory K drawn when the cutter blade 13 advances from the position C1 to the position C2 is an inclined line having a rising gradient with respect to the horizontal.

By forming such a structure, when the medium pressing member 12 is applying a downward force to the platen member 14, the concave groove 3 c which is a traveling portion of the cutter blade 13 is not used. A step in the downward direction is formed, and as described in the example shown in FIG. 7, an ideal sheet cutting angle α can be formed without increasing the groove width dimension of the concave groove portion 3c, Stable cutting of paper can be performed.

Further, when the medium pressing member 12 is not pressing the slide member 14 as in the case of, for example, paper conveyance, the slide member 14 is pressed upward by the pressing force of the spring 17. A regulating hook 15 attached to the lower portion of the slide member 14 engages with a stopper 16 attached to the downstream platen 3b, so that the upper surface of the slide member 14 is at substantially the same height as the upper surface of the upstream platen 3a. , So that the sheet 2 conveyed on the platens 3a and 3b is not obstructed.

That is, in this case, the upper surface of the slide member 14 and the upper surface of the upstream platen 3a have substantially the same height, and no step is formed between the two upper surfaces. For this reason, even when the cut sheet 2 is stuck to the downstream platen 3b, the upstream end of the sheet 2 is located at substantially the same height as the upstream platen 3a. Therefore, the downstream end of the sheet to be printed next comes into contact with the upstream end of the preceding sheet 2 and is pushed in the transport direction. For this reason,
Unlike the conventional case, the paper 2 printed later is not rubbed on the printing surface of the cut paper 2 printed earlier,
The paper 2 is stably conveyed, and an image without any trouble can be obtained.

Further, the cutter blade 13 has a platen 3
Since the paper cutting is performed while gradually ascending not by being horizontal with respect to a and 3b but by always having an ascending slope,
The reciprocating operation of the cutter blade 13 described above can be performed, and the use area of the cutter blade 13 can be changed as needed. For this reason, the cutter blade 13 does not have a reciprocating mechanism for the cutter device.
Life can be greatly improved.

As is clear from the above description, according to the present embodiment, the problems of the paper cutting means of the ink jet printer according to the prior art and the adverse effects caused by the provision of the paper cutting means are eliminated and a stable operation is achieved. Paper conveyance and paper cutting can be performed. Further, since the above-described mechanism is configured very simply, the present invention can be easily applied to various image forming apparatuses such as known inkjet printers, other copiers, and printers other than those described above. Accordingly, the same operation and effect as in the present embodiment can be obtained in any ink jet printer or image forming apparatus.

Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above embodiments, and it is needless to say that various changes can be made without departing from the spirit of the present invention. Nor. For example, in the embodiment shown in FIG. 1 to FIG.
However, in actual use, if a leaf spring or the like obtained by bending a metal material is used, as described above, different spring pressures are provided for each of the slide members 14 in the lateral direction. can do.

[0046]

According to the invention having the structure described in claim 1,
When the cutter blade travels through the concave groove of the print-medium supporting surface to cut the print-medium, the slide member that sandwiches the print-medium in cooperation with the medium pressing member is perpendicular to the medium-support surface. By moving in the direction, a step is formed between the medium supporting surface and the slide member, so that the print-receiving medium is arranged at an angle to the print-receiving medium supporting surface in the concave groove portion. As a result, a sharp paper cutting angle with good cutability is formed by the cutter blade and the printing medium. Further, the present invention, when transporting the print-receiving medium,
Since a step is not formed between the slide member and the medium supporting surface, even when the cut print medium is stuck, the print medium can be stably conveyed. Can be obtained, and it is possible to obtain an image having no defect. Further, in the present invention, since the paper cutting is performed while moving the cutter blade up and down, the reciprocating operation of the cutter blade is performed,
The working area of the cutter blade is changed at any time to make the cutter blade 13
Life can be greatly improved.

Further, according to a second aspect of the present invention, when the slide member is moved upward by an elastic urging means, the upper surface of the slide member is provided. Since the restricting means for restricting the print medium from rising higher than the upstream side medium supporting surface is provided, even when the upper surface of the slide member moves upward, when the cut medium is not cut, Since it does not rise above the medium support surface on the side, the medium to be printed can be satisfactorily conveyed.

According to a third aspect of the present invention, the slide member according to the second aspect corresponds to the traveling path of the medium pressing member so as to face the medium pressing member with the print target medium interposed therebetween. Since the slide member is arranged corresponding to the traveling path opposite to the medium pressing member, when the medium to be printed is cut, Only when the medium pressing member presses the printing medium, the slide member can sink into the medium supporting surface, and the above-described effects can be reliably obtained.

Further, the invention according to claim 4 is the same as the invention according to claim 3.
The biasing means provided in the slide member according to the above, comprises a plurality of spring bodies having different displacement lengths for the same load in the reciprocating direction, the plurality of spring bodies, the printing medium of the print medium Since the individual displacement lengths are arranged in the cutting direction in the order of decreasing length, the cutting position of the cutter blade with respect to the print-receiving medium moves because the slide member does not sink evenly with respect to the print-receiving medium supporting surface. Therefore, the above-described effect can be reliably obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a main part of an ink jet printer that is an embodiment of an image forming apparatus according to the present invention.

FIG. 2 is an enlarged perspective view illustrating a main part of the ink jet printer shown in FIG.

FIG. 3 is a schematic explanatory view showing the operation of the ink jet printer shown in FIG.

FIG. 4 is a schematic perspective view showing an ink jet printer as a typical example of an image forming apparatus.

FIG. 5 is a perspective view showing a main part of the cutter device of the ink jet printer shown in FIG. 4;

FIG. 6 is an explanatory sectional view of a main part showing a configuration of the cutter device shown in FIG. 5;

FIG. 7 is an explanatory sectional view of a main part showing an angular relationship between a cutter blade and a sheet when cutting the sheet in the cutter device shown in FIG. 6;

FIG. 8 is a perspective explanatory view showing a state where electrostatic attraction of paper occurs in the cutter device shown in FIG. 5;

[Explanation of symbols]

 2 Paper 3a Upstream platen 3b Downstream platen 3c Depressed groove 12 Medium pressing member 13 Cutter blade 14 Slide member 15 Restriction hook 16 Stopper 17 Spring 18 Spring holder

Claims (4)

[Claims] 1. A cutter blade which travels in a direction transverse to a transport direction of a print-receiving medium to cut the print-receiving medium, and at least a downstream side of the cutter blade in the transport direction of the print-receiving medium. And a medium pressing member that travels with the cutter blade while pressing the print-receiving medium against the medium supporting surface side, and extends in the traveling direction of the cutter blade so as to accommodate a tip portion of the cutter blade. A groove provided on the medium support surface, and a medium support surface downstream of the groove in the transport direction of the medium to be printed is lower than the medium support surface on the upstream side through a step. In the image forming apparatus arranged in the position, extending in the running direction of the cutter blade and the medium pressing member,
A slide member for sandwiching the print-receiving medium between the medium press member and the slide member, the slide member being reciprocally mounted in a direction of a step on the medium support surface, and pressing the slide member against the medium. Elastic urging means for pressing the member toward the member side and elastically sinking the slide member by the pressing force of the medium pressing member is provided, and the elastic urging means includes a cutter blade and a medium pressing member. An image forming apparatus, wherein the amount of sinking of the slide member by the medium pressing member is varied along the traveling direction. 2. The slide member according to claim 1, wherein the upper surface of the slide member does not rise higher than the upstream medium support surface when the slide member moves upward by the elastic urging means. The image forming apparatus is provided with a restricting means for restricting the image forming apparatus as described above. 3. The elongate member according to claim 2, wherein the slide member is disposed along the traveling path of the medium pressing member so as to face the medium pressing member with the print target medium interposed therebetween. An image forming apparatus comprising: 4. The resilient biasing means provided on the slide member according to claim 3, is composed of a plurality of spring members having different amounts of displacement with respect to the same load in the reciprocating direction. The image forming apparatus is characterized in that the spring members are arranged in the order of decreasing displacement along the running direction of the cutter blade and the medium pressing member.