JPH0358880B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a sheet feeding device that feeds corrugated sheets or similar sheets of paper, metal, plastic, etc. one by one to a required processing device such as a punching device or a printing device. It is related to.

A conventionally known basic sheet feeding device has a kicker that moves back and forth at the bottom of the hopper, and pushes the sheets stacked in the hopper forward one by one starting from the lowest layer, allowing only one sheet to pass through. The sheet is passed through a front ruler plate whose lower clearance is adjusted so as to be captured by a supply roller provided in front of the hopper, and then supplied to a required processing device via the roller.

However, with the method of ejecting the sheet using only the pusher, there is a problem that if the sheet is warped, the engagement between the pusher and the sheet becomes insufficient, and the sheet gets caught on the front ruler plate, causing a feeding error. In addition, in the case of a sheet with low rigidity or a corrugated sheet whose flute lines are oriented horizontally (the flute lines are perpendicular to the supply direction), buckling may occur at the part that engages with the kicker, causing damage to the sheet. There is also the problem of errors in supply timing and supply errors.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a sheet feeding device that does not cause sheet feeding errors and does not cause sheet buckling.

In order to solve the above problems, this invention
A suction box is provided over almost the entire area of the bottom of the hopper, and the suction box is installed so that the entire or part of the suction box can be moved with a constant stroke in the sheet feeding direction, and the suction box is moved in the same direction in conjunction with the movement of the box described above. A picker that moves is provided at the rear of the bottom of the hopper, and a suction action is exerted over the range where the leading edge of the sheet is captured by the supply roller from the beginning of sheet feeding through the opening/closing switching device of the internal air suction port of the suction box. It is.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

The illustrated embodiment is an example applied to a sheet punching device as shown in FIG.

This sheet punching device includes a sheet feeding device 3, a punching device 4, a punching waste separating device 5, a punching sheet separating device, and a gripper margin release device, in the middle of the transport path of an endless chain conveyor 2 in which grippers 1 are provided at regular intervals. A device 6 is provided, and each device is mechanically coupled to match the timing.

The punching device described above is provided in front of the sheet feeding device 3 and rotates at the same speed as the feeding speed or slightly faster than the feeding speed. Supply roller 7
Then, in front of the roller 7, the release cam 8 is released in time with the supply, and the supply is supplied to the gripper 1, which is running at the same speed as the rotational speed of the supply roller 7, and is thereafter held in the gripper 1. In this state, punching, separation of punching waste and punched sheets, and release of the blipper margin are performed in order. The punched sheet is taken out onto a conveyor 9,
The punching waste and the gripper margin are adapted to be removed onto a common discharge conveyor 10.

Now, as shown in the plan view of FIG. 2, the sheet feeding device 3 described above is provided with a movable suction box 13 between the supply roller 7 and the bag guide 12, and fixed suction boxes 14,
14 and 15, and a kicker 16 is provided on the upper surface of the rear fixed suction box 15 below the back guide 12. Along the above-mentioned supply roller 7, a front ruler plate 17 (see FIG. 3),
Horizontal ruler plates 18, 18 are provided along the fixed suction boxes 14, 14 on both sides, and the inner surface of the back guide 12 forms a rear ruler plate 19. The front ruler plate 17 is mounted so that its position can be adjusted in the vertical direction, and the lower clearance is adjusted according to the thickness of the sheets a so that the sheets a can pass one by one. The front, side, and rear ruler plates 17, 18, 18, and 19 constitute a hopper 20 (see FIG. 1), and a large number of sheets a are stacked in the hopper 20.

A drive shaft 21 (see FIGS. 3 and 7) is provided below the movable suction box 13, and a crank arm 22 and a connecting rod 2 are attached to the drive shaft 21.
A movable suction box 13 is connected via 3. This movable suction box 13 is slidably supported at both sides by sliding contact parts 25 of guide members 24, 24 (see FIG. 7), which are fixed parts of the device, and is rotated by the constant rotation of the drive shaft 21. The reciprocating rotation of the horn allows it to move back and forth in a horizontal plane with a constant stroke.

Further, the back and forth movement of the kicker 16 is also provided by the same drive shaft 21 as described above. That is, as shown in FIG. 7, slide members 26, 26 are attached to the lower surface of the left and right sides of the kicker 16, and each slide member 26, 26 is attached to a pair of opposing guide members 2.
It is slidably supported by sliding contact members 28 provided at 7 and 27, respectively. Further, the slide member 26 is attached to the drive shaft 21 on the crank arm 2.
9 and a connecting rod 30.

Therefore, the reciprocating rotation of the drive shaft 21 causes the suction box 13 and the kicker 16 to move back and forth in synchronization.

The kicker 16 is attached to slide members 26, 26 so that its position in the front-rear direction can be adjusted. The relationship between the kicker 16 and the back guide 12 is as shown in FIG. The engaged plate 31 is hidden under the rear ruler plate 19.

Therefore, the sheet a in the hopper 20 rests on the upper surface of the tip of the picker 16, and when the picker 16 moves forward, it engages with the engagement plate 31 and is pushed forward.

As shown in FIG. 5, the movable suction box 13 has a U-shaped notch 32 formed at its front edge, and when the suction box 13 moves forward, the central roller 7a of the supply roller 7 moves into the notch. When the sheet a is caught by the supply roller 7, the moving speed of the suction box 13 reaches its maximum. and the supply roller 7
The rotation speed is set to be the same as or slightly slower than the rotation speed of.

The front end of the suction box 13 when the sheet a starts to move forward is located at the rear of the front ruler plate 17, so that the front end does not move beyond the axis of the roller 7. You may. However, also in this case, the relationship between the speeds of the suction box 13 and the supply roller 7 when the sheet a is captured by the supply roller 7 is set in the same manner as described above.

As shown in FIGS. 4 and 5, a large number of small holes 33 are formed on the upper surface of the suction box 13.
Also, a part of its lower surface is in contact with a slide plate 34 provided on the guide member 24 (see FIG. 7) on both the left and right sides, and the slide surface on the suction box 13 side is connected to the inside of the box 13 and A communication port 35 that is long in the front-rear direction is formed. Furthermore, a suction port 36 is formed in the slide plate 34 so as to face each communication port 35 . The suction port 36 is connected to the duct 3
7 and a branch joint 38 to a negative pressure source.

Note that the above-mentioned both-side fixed suction boxes 14 are also connected to a negative pressure source through a duct 39 and a branch joint 38 common to the above. Further, the rear fixed suction box 15 is connected to the rear fixed suction box 15 by a duct 40 shown in FIG.
connected to the same negative pressure source. Further, the rear fixed suction box 15 and the back guide 12 are connected to the connecting member 4.
1, and when the back guide 12 is moved according to the size of the sheet a, the suction box 15 is also moved together. In this case, Kitzker 16
The position of the back guide 12 in the front and back direction is adjusted as appropriate according to the movement of the back guide 12.

Now, the communication port 3 of the movable suction box 13
5 and the suction port 36 of the slide plate 34. At the beginning of the stroke of the movable suction box 13, the suction port 36 aligns with the communication port 35 as shown in FIGS. It has been switched to hold. The distance L ₁ from the front end of the communication port 35 to the front end of the slide plate 34 is the front ruler plate 17
It is approximately equal to the distance L ₂ from the center of the supply roller 7 to the center of the supply roller 7. Note that these distances L ₁ and L ₂ are smaller than the stroke L ₃ of the suction box 13 (see FIG. 5).

Therefore, the stroke of suction box 13
In the middle of L ₃ , the suction box 13 moves at a distance L ₁
The interior of the box 13 is maintained at a negative pressure until it is moved. Also sheet a
moves a distance L ₂ together with the suction box 13 and is captured by the supply roller 7. When the sheet a is captured by the supply roller 7, almost at the same time, the interior of the suction box 13 is switched to be exposed to the atmosphere.

It is also possible to reverse the positional relationship between the communication port 35 and the suction port 36, that is, to provide the oblong hole communication port on the fixed side and the circular suction port on the movable side.

Furthermore, when the sheet a is captured by the supply roller 7, the communication port 35 and the suction port 36 are switched to close, and since the moving speed of the sheet a becomes faster than that of the suction box 13, a small The holes 33 gradually increase until the suction box 13
Since the inside of the holder is open to the atmosphere, the communication port 35 does not necessarily have to be configured to be switched to communicate with the atmosphere.

In addition to the above-mentioned device having the communication port 35 and the suction port 36, the switching device that connects or closes the inside of the suction box 13 and the negative pressure source in relation to the stroke movement of the suction box 13 can be A switching device may be used in which an on-off valve is provided in the middle of a duct connecting the box 13 and the negative pressure source, and the valve is switched in relation to the sliding movement of the suction box 13.

Furthermore, the device may be configured to send positive pressure or atmospheric air into the interior of the suction box 13 in place of negative pressure at the same time as the switching associated with the sliding movement of the suction box 13.

The embodiment of the present invention has the above structure, and its operation will be explained next.

When a large number of sheets a are stacked on the hopper 20, the lowest sheet a is placed on the tip of the picker 15. When the negative pressure source is applied, the sheet a is attracted to the upper surface of each suction box 13, 14, 14, 15, and in particular, the rear fixed suction box 15 securely presses the end of the sheet a against the engagement plate 31 of the kicker 16. and eliminates ejection mistakes. Further, the fixed suction boxes 14, 14 on both sides serve to assist the suction force exerted by the movable suction box 13.

Due to these suctions, even if the sheet a is warped, it is reliably attracted to each suction box 13, 14, 14, so that it is fed one by one to the supply roller 7 without being caught by the front ruler plate 17.

When the drive shaft 21 is driven from the above state, the movable suction box 13 and the picker 16 start moving forward together, and the lowermost sheet a is sent forward by both the picker 16 and the movable suction box 13. In this way, the picker 16 and the movable suction box 13 move forward by one stroke, but in the middle of this stroke, the leading edge of the sheet a reliably reaches the supply roller 7, which is rotating at the same speed as or faster than the feeding speed of the sheet a. captured by At almost the same time, the internal pressure of the movable suction box 13 is quickly released to normal pressure, so that the sheet a does not slip between it and the supply roller 7, and therefore, there is no mismatch in the supply timing. , held by gripper 1.

In the above embodiment, the fixed suction boxes 14, 14, 15 are provided on both sides and rear of the movable suction box 13, but these fixed suction boxes 14, 14, 15 are particularly suitable for preventing warping of the sheet a. movable suction box 13 when
Therefore, it may be omitted if the suction force of the movable suction box 13 is sufficiently large or if the warpage of the sheet a is small.

As described above, the device of the present invention has a suction box that moves with a constant stroke in the front-rear direction and a kicker. Even if the sheet has a warp, the suction box suctions the sheet and the sheet is straightened flat before being ejected by the kicker. I can do it. Therefore, the suction box is provided over almost the entire bottom of the hopper, which eliminates sheet feeding errors, prevents partial buckling of the sheet, and ensures accurate feeding timing. You can reliably send out one sheet at a time without getting caught on the front ruler. Furthermore, the suction action of the suction box is stopped when the leading edge of the sheet is captured by the supply roller by the opening/closing device of the suction port, so that the portion of the sheet remaining on the suction box can be accurately moved by the supply roller with less frictional resistance. It is brought out at the right time.

[Brief explanation of drawings]

Fig. 1 is an overall view of the punching device, Fig. 2 is a plan view of the sheet feeding device, Fig. 3 is a sectional view taken along the - line in Fig. 2 (however, the suction box is partially omitted), and Fig. 4 is a plan view of the sheet feeding device.
The figure is a sectional view taken along the - line in Fig. 5, Fig. 5 is a partially enlarged cross-sectional plan view of Fig. 2, and Fig. 6 is a - line in Fig. 2.
7 is a partially omitted side view of the sheet feeding device. 3... Sheet supply device, 7... Supply roller, 1
3...Movable suction box, 14, 15...Fixed suction box, 16...Kicker, 20...Hopper, 21...Drive shaft, 22...Crank arm,
23...Connection rod.

Claims (1)

[Claims] 1 In a sheet feeding device that feeds sheets loaded in a hopper one by one to a feeding roller provided at the front of the bottom of the hopper, a suction box is provided over almost the entire bottom of the hopper, and the entire or part of the suction box is used to feed out the sheets. A kicker is installed at the rear of the bottom of the hopper and moves in the same direction in conjunction with the movement of the box, and an opening/closing switching device for the internal air suction port of the suction box is provided. A sheet feeding device characterized in that a suction action is exerted over a range where a leading edge of a sheet is captured by a feeding roller from the beginning of sheet feeding.