JPS6116276Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a shielding structure for a sheet suction section in a pneumatic sheet feeding device. Specifically, a plurality of sheets stacked on a sheet mounting table are suctioned into a sheet suction unit in order from the topmost sheet using negative pressure, and the suctioned sheets are The present invention relates to a shielding structure for regulating the flow path of outside air to the sheet suction section in an air-type sheet feeding device that feeds sheets toward a processing section by a sheet feeding member.

The pneumatic sheet feeding device sucks, separates and feeds multiple sheets stacked on a sheet stack, starting from the topmost sheet, so the size of the sheets and their rigidity ( So-called lower back strength)
However, it has an excellent feature of being able to separate and feed different sheets, and has been put into practical use mainly as a sheet feeding device for facsimile machines.

As one of the pneumatic sheet feeding devices, a vacuum plate having a sheet suction hole defined by a casing and facing the sheet mounting table is provided above the sheet mounting table, and A sheet suction section formed by the vacuum plate and both side plates of the casing is selectively brought into a negative pressure state, and the plurality of sheets stacked on the sheet mounting table are moved to the top of the stack. Starting from the top sheet, suction is applied to the vacuum plate mentioned above.
In this state, pass the above vacuum plate,
A sheet feeding roller rotatably disposed inside the casing with a part of its peripheral surface exposed to the side of the sheet mounting table is driven to rotate, and the sucked sheet is fed toward the processing section. The device is known.
This device sucks the air in the suction section by rotating a fan, and by bringing the suction section into a negative pressure state, the uppermost sheet on the sheet mounting table is removed.
The sheet is separated from other sheets by suctioning upward, but if the suction section is configured by simply making the sheet mounting table and the vacuum plate face each other, the rotation of the fan will At the same time, the air in this suction part is sucked and becomes a negative pressure state, but the outside air flows in from the opening at the rear of the seat all at once, and the air flow pressure flowing into the vacuum plate mentioned above, on the contrary, It has the disadvantage that it acts to press down the placed sheet from above, significantly reducing the sheet suction and separation effect. On the other hand, if the opening at the rear of the sheet of the suction section is simply shielded, the other three sides of the sheet suction section will be kept airtight by the side plates of the casing, the guide plate of the sheet, etc. due to its structure. Because of this, the airtightness of this suction part becomes extremely high, and the sheet suction effect increases. There is a risk of being sent.

The fact that a large number of sheets are sucked or fed in the sheet feeding device of a facsimile is that when the fan stops and the sheets float once and fall, they do not return to their original position and become skewed. This is extremely undesirable, as the transmitting and receiving functions in the processing section may no longer function properly with respect to the sheets, or may cause paper jams. Therefore, this type of apparatus requires a sheet feeding device that can reliably suck and separate sheets.

The object of this invention is to provide an improved pneumatic sheet feeding device that can more reliably suck, separate, and feed sheets in response to the above-mentioned requirements.

The purpose of this is to make the rear part of the sheet of the suction section airtight with a shielding member in the above-mentioned pneumatic sheet feeding device, and also to make the sheet guide plate disposed in front of the sheet loading table suction from the outside. This is achieved by having a structure with an air inflow section through which outside air flows into the section.

This invention will be explained below with reference to an illustrated embodiment. Note that in the embodiments shown below, a roller is used as the sheet feeding member, but the sheet feeding member may be in the form of a belt.

FIG. 1 is a schematic diagram showing the principle of an embodiment in which the pneumatic sheet feeding device provided by this invention is applied to a facsimile machine. In FIG. 1, reference numeral 1 indicates a processing section, 2 a sheet, 4 a sheet feeding roller, 10 a fan, 11 a casing, 27 a sheet mounting table, and 35 a vacuum plate. This sheet feeding device rotates a fan indicated by the reference numeral 10 to move inside a casing 11 surrounding a sheet feeding roller 4.
The air layer between the casing 11 and the upper surface of the sheet 2a is thinned by the negative pressure, and the uppermost sheet of the stacked sheets 2 is placed in the casing 11.
In this state, the sheet feeding roller 4 is rotated to feed the sheet 2 toward the scanner roller 3. The sheet 2 fed from the stacking section by the sheet feeding roller 4 is designated by the symbol 1.
2 and this roller 1
A sheet separation device 14 configured with a friction plate 13 that elastically contacts the circumferential surface of the processing section 1 prevents multiple sheets from being fed, and only the uppermost sheet is transferred to the processing section 1. Further shipments will be made to The sheet 2 that has passed through the sheet separation device is guided by the guide roller 15, passes below the auxiliary roller 5 while bypassing it, and the leading end contacts the scanner roller 3 and is driven to rotate. It is caught between the presser roller 16 and the presser roller 16. sheet 2
is conveyed to the processing section 1 by the rotation of the scanner roller 3, and in the processing section 1, the scanner 1
7. After being sequentially read or recorded by the recording needle 18, it is further conveyed by another scanner roller 19 toward another processing section.

Figure 2 is based on the schematic diagram shown in Figure 1 above.
1 is a diagram showing an example of a specific configuration when the present invention is implemented in a pneumatic sheet feeding device in a facsimile machine.

In FIG. 2, reference numeral 1 is a processing section, 2 is a sheet, 3 is a scanner roller, 4 is a sheet feeding roller, 5 is an auxiliary roller, 7 is a detour for the sheet 2, 10 is a fan, 11 is a casing, 12 13 is a sheet separation roller, 13 is a friction plate, and 14 is a sheet separation device. 15 is a guide roller, 16 is a presser roller, 17 is a scanner, 18 is a recording needle, 1
9 indicates other scanner rollers. The series of operations of each of these members is almost the same as that described in the explanation of FIG. It shall be.

In FIG. 2, the sheet processing section 1 is disposed inside a facsimile main body 20, and includes a pair of guides disposed opposite to each other along a sheet path between the pair of scanner rollers 3 and 19. A scanner 17 and a recording needle 18 are arranged with the image reading section and the recording section facing the plates 21 and 22 and the sheet path from below.
It is made up of. In the sheet path upstream from the scanner roller 3, along this path,
Another pair of guide plates 23 similar to the above guide plates,
24 are arranged. Each of these guide plates is held between both side walls (not shown) of the facsimile main body. Further, each scanner roller 3, 19 and each presser roller 16, 25 in pressure contact with these rollers are rotatably held between the above-mentioned both side walls, and are driven by a step motor (not shown) (which uses clock pulses as input to rotate a predetermined angle). , rotates in successive steps), respectively.

Each of the guide plates 21, 22 and 23, 24 is provided with through holes facing each other, and a sheet formed by a combination of a light receiving element and a light emitting element is inserted through each of these through holes. Detector
Sheet detection optical paths S ₁ and S ₂ are formed, respectively. Sheet passage upstream end 24a of guide plate 24
is a document guide plate 26 for guiding a facsimile transmission document (not shown) to the scanner roller 3;
It continues to the end closer to the main body.

The sheets 2 are stacked and placed on the sheet mounting table 27. The sheet mounting table 27 has L on both sides thereof.
A pair of ear pieces 2 bent downward in a letter shape
7a (the one in front is not shown) is casing 1
It is fixed to the lower part of the casing 11 (above the document guide plate 26) by being clamped and fixed to both side plates 11a of the document guide plate 11. The end of the sheet mounting table 27 closer to the facsimile main body is bent upward into an L-shape, and this bent portion forms a paper stopper 27b. A lug 28 is formed substantially integrally with this paper stopper 27b.
A friction plate 13 is pivotally supported at 8.
The hanging piece 29a and the ear piece 28, which are integrally formed with the support member 29 of the friction plate 13, are connected to each other by a compressible spring 30. The support member 29 is given a left-handed sliding property around the support shaft 31 by the tension force of the spring 30, and the rotation of the friction plate 13 due to this sliding property is caused by the upper surface of the friction plate 13 being This is prevented by contacting the peripheral surface of the

The casing 11 is formed in the shape of a barrel, and inside thereof, two upper and lower housings 33 and 34 are formed by a partition plate 32 parallel to a top plate 11b located in the midsection. Lower housing 3
The lower opening of 4 is covered by a vacuum plate 35.

This vacuum plate 35 is formed by being bent in a step-like manner so that only the sheet feeding roller 4 is accommodated in the lower housing 34, and the portion corresponding to the sheet feeding roller 4 is A large number of relatively large elongated holes 35a are bored in parallel in a comb-like shape so that the peripheral surface of the feeding roller 4 extends from below the vacuum plate 35. Each of these elongated holes 35a also serves as an air intake port of a fan to be described later.

The sheet feeding roller 4, the auxiliary roller 5, and the sheet separation roller 12 are arranged on individual support shafts 4a, 5.
A and 12a are each fitted with a plurality of coin-shaped rollers at regular intervals.

A one-way rotating clutch (not shown) is installed between each of the support shafts 4a and 12a of the sheet feeding roller 4 and the sheet separation roller 12 and the rollers fitted to these support shafts. ,
The individual rollers can freely rotate relative to the respective support shafts 4a, 12a in the forward direction, that is, in the counterclockwise direction in the figure.

A thrust spring (wave washer) is interposed between the support shaft 5a of the auxiliary roller 5 and each roller fitted thereto. ), the support shaft 5a slips against each roller fitted to it due to the action of a thrust spring (not shown), causing an abnormality in the feed motor (described later). It is designed so that no load is applied.

Each of the support shafts 4a, 5a, 12a and the guide roller 15 rotate between the side plates 11a of the casing 11, perpendicular to the sheet feeding direction and approximately parallel to the stacked sheet surfaces. It is freely supported. Each of these support shafts 4
Pulleys 4b and 12b are mounted on the front ends of the pulleys 4b and 12b via spring clutches (not shown), respectively. Also,
A pulley 5b is fixed to the end of the support shaft 5a. Each of these pulleys is attached to the upper housing 3
The drive pulley 36 is rotatably supported on the casing side plate of No. 3, and the idler pulleys 37 and 38 are supported similarly to the drive pulley 36.
are connected by a timing belt 39.

The drive pulley 36 is coaxially integrated with a worm wheel 40, and the worm wheel 40 is driven by a worm 42 fixed to a drive shaft of a feed motor 41. The feed motor 41 is fixed on the partition plate 32 inside the upper housing 33. This upper housing 3
A fan 10 of a type in which rotary blades are arranged around the motor is fixed on the partition plate 32 of No. 3.
As the fan 10 rotates, the air in the lower housing 34 is released to the outside of the housing through the opening 32a of the partition plate 32 with respect to the upper housing and the mesh opening 11c provided in the upper part of the casing 11. The inside of the lower housing becomes under negative pressure. A solenoid 43 for the sheet feed roller clutch and a solenoid 44 for the sheet separation roller clutch are provided on the inner wall of the upper housing 33.
are fixed, respectively, and one arm end of each two-arm rod 45, 46 is engaged with each slider 43a, 44a of each solenoid 43, 44. The other arm end of each two-arm rod 45, 46 is bent into an L-shape, and the bent portion is connected to each ratchet wheel coaxially fixed to the support shafts 4a and 12a. They are engaged with claws 47 and 48, respectively. The fan 10 is activated by pressing a start button (not shown), and the lower housing 34
is placed in a negative pressure state, and the sheet 2 on the sheet mounting table 27 is placed in a negative pressure state.
Place the topmost sheet on Bakyum Plate 3.
Suction to the bottom surface of 5. The operation of the fan 10 is stopped when the leading end of the sheet 2 blocks the sheet detection optical path of the sheet detector S ₁ and receives a signal output from the sheet detector S ₁ . feed motor 41
starts operating at substantially the same timing as the fan 10, and rotates each pulley 4b, 5b, 12b via the timing belt 39, respectively. As each pulley rotates, only the auxiliary roller 5 rotates. The operation of the feed motor 41 stops a while after the rear end of the sheet 2 receives a signal that opens the sheet detection optical path of the sheet detector _S2 . Each solenoid 43, 44 is energized several seconds after the fan 10 is activated, and each two-arm rod 45,
The respective arm ends of 46 are released from the claws of each ratchet wheel 47, 48, and the rotation of each pulley 4b, 12b is
Each support shaft 4a, 12a via a spring clutch
The sheet feeding roller 4 and the sheet separating roller 12 rotate respectively. The solenoid 43 is energized by a signal that causes the tip of the sheet 2 to cut the optical path of the sheet detector _S1 , and the solenoid 44 is energized by a signal that causes the tip of the sheet 2 to cut the optical path of the sheet detector S1.
Each is solved by the signal that cuts the optical path of S ₂ ,
As a result, the rotation of the sheet feeding roller 4 and the sheet separating roller is sequentially stopped.

This invention, as shown in FIGS. 1 and 2, uses a sheet mounting table 27, a vacuum plate 35, and both side plates 11a of the casing (see FIG. 2) in the above-mentioned pneumatic sheet feeding device. The rear part of the sheet (on the left in FIG. 2) of the sheet suction unit 100 to be formed is made into a substantially airtight state by the shielding member 200, the roller support part 200, or the sheet pressing roller indicated by the reference numeral 50. The sheet guide plate 300 disposed in front of the sheet mounting table 27 (on the right side in FIG. 2) is structured to have an air inflow section through which outside air flows. That is.

That is, in the above-mentioned embodiment, as shown in FIG. 2, the sheet pressing roller 50 and the supporting plate 200 of this roller press the rear part of the sheet in the sheet suction section 100, and The inflow of air from the rear of the seat is softened to prevent the sheet from moving wildly, the base is fixed to the front end 27c of the sheet mounting table 27, and the free end is brought into contact with the circumferential surface of the guide roller 15. ,
On the sheet guide plate 300, as shown in FIG.
A comb-shaped air inflow portion 300a is formed.

According to this embodiment, the sheet presser roller 50
Since the rear part of the sheet is held down by the fan 10, the sheet does not move wildly when suctioning the sheet, and the rear part of the sheet of the sheet suction section 100 is kept in a substantially airtight state by the roller support plate 200. Since the inflow of outside air from the rear of the seat during the rotation of the seat is extremely small, it is possible to avoid a situation where the upper surface of the seat is pressed by the airflow pressure of this outside air and the suction effect is reduced. Although the roller support plate 200 makes the rear part of the seat substantially airtight, since the air inlet part 300a is formed in the seat guide plate 300, the pressure inside the suction rate 100 may be abnormally reduced. In addition, the outside air flowing into the suction unit 100 from the air inflow unit 300a is blown into the tip of the stacked sheets 2, so that it acts to promote separation of the sheets.
Suction of multiple sheets is extremely unlikely to occur.

As described above, this invention has the effect of significantly increasing the essential sheet suction and separation functions in a pneumatic sheet feeding device due to its extremely simple configuration, and its description is as follows. objectives are achieved.

In addition, in the above example, the roller support plate serves as a support for the roller 50.
It is formed of a rigid plate like a roof that covers the top of the
For example, it may be a rubber plate or a Mylar sheet. Further, the air inflow portion 300a of the sheet guide plate 300 has a sheet end portion that is connected to the air inflow portion 300a.
It has a comb-toothed shape to prevent it from getting stuck in a. For example, as shown in FIG. 4, this sheet guide plate may have an elongated hole 300b that widens towards the end in the sheet traveling direction A as an air inlet, and as shown in FIG. The sheet guide plate 300 itself is not provided with the above-mentioned air inflow part, and a distance piece or a member (which performs an equivalent function) is provided between the end 27a of the sheet mounting table 27 and the base of the sheet guide plate 300. For example, a gap 400 may be formed at the end of the sheet mounting table 27 (by forming an angle integrally therewith), and this gap may be used as the above-mentioned air inflow section.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing the principle of an embodiment of this invention, Fig. 2 is a schematic diagram of the above embodiment, Fig. 3 is a perspective view of the main constituent members in the above embodiment, and Fig. 4 is a schematic diagram showing the principle of an embodiment of the invention.
The figure is a plan view showing another embodiment of the above-mentioned structural member, and FIG. 5 is a sectional view showing still another embodiment of the above-mentioned structural member. DESCRIPTION OF SYMBOLS 1... Processing part, 2... Sheet, 4... Sheet feeding roller, 10... Fan, 11... Casing, 27... Sheet mounting table, 35... Vacuum plate, 100... Suction part, 200 ... Shielding part, 300 ... Sheet guide plate, 300a, 30
0b, 400... Air inflow section.

Claims (1)

[Scope of utility model registration request] A vacuum plate having a sheet suction hole defined by a casing is provided above the sheet mounting table, facing the sheet mounting table, and air in the casing is sucked by rotation of a fan, A sheet suction section formed by a sheet mounting table, the vacuum plate, and both side plates of the casing is selectively brought into a negative pressure state to remove a plurality of sheets stacked and placed on the sheet mounting table. ,
The uppermost sheet is suctioned into the vacuum plate in order, and in this state, a part of the sheet feeding member is exposed to the side of the sheet mounting table through the vacuum plate, and the sheet is placed inside the casing. In the pneumatic sheet feeding device that drives the sheet feeding member and feeds the suctioned sheet toward the processing section, the rear part of the sheet in the suction section is kept in a substantially airtight state with a shielding member. At the same time, the sheet guide plate installed in front of the sheet mounting table,
A shielding structure for a sheet suction section, characterized in that it has a structure having an air inflow section through which outside air flows into the suction section from the outside.