JP2836933B2 - Paper feed timing correction device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a paper feed timing correcting device configured to be able to correct the paper feed timing in a paperboard transport unit installed in a cardboard sheet making machine or the like. .

(Prior Art) A conventional paper feeder will be described with reference to FIGS. 3 to 5. FIGS. 3 to 5 show the configuration of a conventional paper feeder using a lead-edge method and problems in the apparatus. FIG. 6 is an operation timing chart of the lead edge feeder. Hereinafter, the structure of the conventional sheet feeding device will be briefly described. As shown in FIG. 3, the paper feeder of this type passes the cardboard sheets 3 stacked on the paper feed table 24 through a gap formed at the lower end of the front guide 1 by rotation of a feed roll 4 provided below the sheet path line.
It is configured to sequentially carry one sheet at a time downstream from the lowermost sheet 3a. A duct 25 is disposed below the corrugated cardboard sheet 3 of the apparatus, and a suction box 6 connected to a suction blower 26 via the duct 25 is provided at a part below the corrugated cardboard sheet 3. The suction box 6 is in a substantially sealed state by shielding the upper suction surface with the lowermost sheet 3a, and a negative pressure area is formed inside by the operation of the suction blower 26, so that the lowermost sheet 3a and the conveying means are used. It functions to increase the frictional force F ₀ of a certain delivery roll 4.

The receiving roll 4 is provided with a receiving plate 5 whose height relative to the outer peripheral surface of the roll 4 can be changed through a hole formed at a portion corresponding to the roll 4. This receiving plate 5
Is configured to be able to move up and down, and to attach and detach the lower surface of the lowermost sheet 3a that comes into contact with the feed roll 4 by moving up and down the receiving plate 5. By lowering the receiving plate 5 from the sheet path line with respect to the sheet 3a. The function of applying the rotational conveyance force of the delivery roll 4 to the sheet 3a and, conversely, raising the receiving plate 5 is to cut off the transport function of the sheet 3a by the delivery roll 4. Now, based on the above structure, the cardboard sheet 3 has a frictional force F ₀ generated between the lowermost sheet 3a and the delivery roll 4, and a frictional force F generated between the lowermost sheet 3a and the second-stage sheet 3b. The sheet is conveyed between the downstream feed rolls 7a and 7b by the action of the frictional force f = F ₀ -F generated on the sheet due to the difference, and the sheet is further conveyed between the downstream feed rolls 7a and 7b by the pinch rotation of the feed rolls 7a and 7b. Sent out to

Next, the operation (function) of the above-described conventional paper feeder will be described. FIG. 6 shows the behavior of the feed roll 4 and the receiving plate 5 on the vertical axis with respect to the machine (paper feed) cycle (horizontal axis). As shown in the figure, the corrugated cardboard sheet 3a comes into contact with the delivery roll 4 by the lowering of the receiving plate 5, is transported by the accelerated rotation (peripheral speed) of the delivery roll, and has the peripheral speed V _{0 of the} downstream feed rolls 7a and 7b. It carried over the transport in E ₁ point matching. At the same time as this takeover, the delivery roll 4 loses the transfer function due to the rise of the receiving plate 5,
Continue then feed roll 4 continues rotating, and stops at point E ₂ after one revolution. After the completion of one cycle, when the next sheet 3b is conveyed, the receiving plate 5 is lowered, and then the delivery roll 4 is rotated again to carry out the sheet 3b to the downstream as described above. Hereinafter, the same behavior is sequentially repeated so that the stacked corrugated cardboard sheets 3 are sequentially carried out from the lowermost sheet side.

(Problems to be Solved by the Invention) The exemplified conventional paper feeder has the above-described configuration and functions, and has the following disadvantages.

In other words, the rising timing of the receiving plate 5 for intermittently engaging the feeding roll 4 and the sheet 3 for carrying out the sheet is always constant (no correction function) with respect to the descending timing. As the size of the sheet becomes longer, the increased frictional force (sliding resistance) F of the lowermost sheet 3a and the second sheet 3b is all reduced by the downstream feed rolls 7a, 7b.
, And a great problem of delaying the sheet feeding timing has occurred.

Also, as shown in FIG. 5, a paper feed deviation (variation in the deviation amount) occurs every time the load conditions such as the machine speed, the weight of the stacked sheets (length, the number of stacked sheets), the material of the sheets (the coefficient of friction), and the like change. In many cases, troubles occur in post-processing such as printing. 4th
The figure shows the variation of the distance x from the front end of the sheet to the print start position 0 with respect to the load condition.
As the load increases with respect to A ₀ (A ₀ → A ₂ ), the distance x ₁
Becomes shorter, and conversely, as the load decreases (A ₀ → A ₁ ), the distance x ₂ tends to become longer. This tendency is caused by the frictional force F, F ₀ on the upper surface and the lower surface of the lowermost sheet 3a due to the change in load.
And the slip amount between the delivery roll 4 and the lowermost sheet 3a fluctuates, whereby the cardboard sheet and the printing plate P on the plate cylinder 21 in the printing section P
The relative positional relationship with the sheet 22 changed, causing the printing position to shift before and after in the sheet 3 flow direction. Incidentally, FIG. 5 is intended specifically showing the trend, if the paper feed timing is delayed with respect to the distance x ₀ to the ideal print start position
x ₁ , and x ₂ when the paper feed timing is too early.

And until now, in order to eliminate such defects,
In the downstream printing process, each unit needs to be provided with a register means (apparatus) in order to correct the deviation of the paper feed timing. However, since the amount of paper misalignment as described above is not constant and is often different for each sheet, it is not satisfactory in the correction in the printing process, and the above-described problem only increases the amount of defective paper generated. In addition, frequent order changes have been a factor in significantly reducing productivity.

As described in the section of the related art, in the conventional paperboard feeder, there is a large variation in the sheet conveyance timing due to a variation in the slip amount between the sheet and a delivery roll which is a conveyance unit of the sheet, and the product quality ( (Accuracy) is reduced. That is, each time a load condition such as a machine speed, a sheet weight (sheet stack height and length), and a sheet material changes, a sheet shift (a large variation in sheet feed timing) occurs, and a downstream process, for example, a printing unit. It was necessary to make registration each time.

The present invention has been proposed to solve these problems.

(Means for Solving the Problems) For this reason, the present invention relates to a paperboard transport device provided in a box making machine for corrugated cardboard sheets and the like. Conveying means for conveying a sheet at a constant speed downstream of a paper feeding device configured to feed, sequentially pinch and convey to a downstream feed roll, and a paperboard abutment claw on an outer surface within a flow direction range of the conveying means. The endless belt to which the sheet is fixed is provided, and a paper feed timing correcting means for driving the traveling while the claw portion is always positioned on a straight line perpendicular to the sheet advancing direction is provided, and the driving speed of the timing correcting means Is capable of increasing or decreasing the sheet feeding speed of the sheet feeding device so that the sheet can be corrected without stopping the traveling of the sheet. It is intended to assist constant-time seat running, and this is used as a means for solving the problem.

(Action) According to the present invention, the end of the paperboard conveyed in a state in which the paperboard is scattered back and forth in the advancing direction due to fluctuations in the load conditions such as the machine speed, the weight of the stacked sheets, the material of the sheet and the length of the sheet is transferred to the endless belt portion. The nail is once braked by the fixed nail, and the nail can be released and transported at a predetermined timing corresponding to the next process printing. As a result, the sheet can be conveyed downstream in a state where the deviation (variation) in the timing of carrying out the sheet from the sheet feeding section is accurately corrected, so that the processing accuracy such as the printing position can be significantly improved.

(Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIGS. 1 and 2 show an example of a paper feed timing correcting device according to the present invention provided in a cardboard sheet box making machine. , FIG. 1 is a schematic configuration diagram, and FIG. 2 is an explanatory diagram of its functions. In FIG. 1 and FIG. 2, a predetermined number of paperboards 3 stacked between the front guide 1 and the backstop 2 are delivered via a delivery roll 4 for sequentially carrying out one by one from the lowermost layer, and a driving device (not shown). The basic structure of the lead-edge type feeder constituted by the receiving plate 5 and the like for intermittently engaging the lowermost sheet 3a with the outer peripheral surface of the delivery roll 4 by moving up and down at the timing of The functions are the same as those described in the section of the related art, and thus detailed description thereof is omitted here.

The present invention relates to a straightening device configured to straighten a front end of a paperboard conveyed through a feeder (sheet feeding device) so as to match a predetermined timing, and then to convey the same to the next process. , Function) will be described.

As shown in FIG. 1, one or a plurality of sets of feed rolls 8, 9, 10 are located at positions adjacent to the downstream feed rolls 7a, 7b of the conventional paper feeder R and above and below the sheet path line.
Are arranged. Pulleys 11 and 12 are rotatably mounted on the shafts of the feed rolls 8b and 9b, respectively, and a pulley 13 is mounted below the feed rolls 9 and 9. A synchro pulley 14 is fixed to a part of the shaft of the pulley 13 supported by the shaft. Synchro pulley 14 and motor 15
The synchro pulley 16 fixed to the shaft end is connected by a synchro belt 17 wound therearound. The motor 15 is configured such that the rotation speed can be arbitrarily set at a predetermined timing by a command signal from a control device 18 calculated based on a feed motor or a feed roll 4 speed by a servo motor or the like. is there. It should be noted that the endless belt speed is the speed diagram (the second
(Fig.)

An endless belt 20 is wound around the above-mentioned pulleys 11, 12 and 13, and a claw 19 configured to abut the front end of the paperboard is attached to the endless belt 20. Although a plurality of the belts 20 are arranged side by side in the machine width direction, one belt may be provided at a substantially central position in terms of function.

Since the paper feed timing correcting device K of the present invention is configured as described above, the corrugated cardboard sheet 3 conveyed from the paper feeding device R is corrected in the travel timing by the correcting device K, and then printed in the next process printing section. The printing is carried out to a target position by the clamping rotation of the printing plate 22 and the impression cylinder 23 wound around the plate cylinder 21 as in the conventional type.

Next, the function will be described with reference to FIG. FIG. 2 is an operation timing chart, in which the rotation angle θ (horizontal axis) of the cam drive shaft which makes one rotation per one cycle of the paper feeding operation,
The vertical axis indicates the ascending / descending timing, the peripheral speed V of the feed roll 4 intermittently driven to rotate, and the running speed V of the endless belt 20 provided with the claw provided in the timing correcting device K of the present invention. After lowering the receiving plate 5 and bringing the lowermost sheet 3a into contact with the outer peripheral surface of the feed roll 4, the feed roll 4 is accelerated and rotated, and the peripheral speed V of the downstream feed rolls 7a and 7b is increased.
The leading end of the corrugated cardboard sheet 3 carried out in a state synchronized with ₀ is clamped between the feed rolls. After that, the feed roll 4 is rotated at the same speed for a predetermined time determined by the sheet length to assist the sheet running. As a result, the load acting on the feed roll 7 can be reduced.

Next, after the feed roll is rotated by a predetermined angle, that is, after the sheet is conveyed by a predetermined length, the conveying action of the feed roll 4 is released by raising the receiving plate 5, and the feed roll 4 is decelerated and stopped. Thereafter, the above operation is sequentially repeated, and the stacked sheets 3 are sent out one by one from the lowermost sheet.

The sheet 3 sent out as described above is carried into the downstream timing correction device K via the feed rolls 7a and 7b. The endless belt 20 running in synchronism with the peripheral speed of the feed roll 7 runs at a high speed immediately before the leading edge of the conveyed sheet arrives, and moves the fixed nail 19 along the sheet path line as shown in FIG. Then, the vehicle is decelerated and waits for the arrival of the sheet 3 to abut against the claws 19 to correct the relative timing with the next step. Subsequently, after running in synchronization with the feed roll peripheral speed V ₀ , the claw 19 engaged with the leading end of the sheet is avoided downward by rotating again at a high speed for a predetermined time. The sheet 3 is continuously rotated at a predetermined speed.
It is clamped by 9 and 10 and sent to the next process printing section P.
The traveling speed of the endless belt 20 that continues traveling is controlled, and the relative position with respect to the cam drive shaft rotation angle is set so as to match the next operation timing. Thereafter, the above behavior is repeated sequentially, and the sheet 3 is accurately conveyed at a predetermined timing corresponding to the downstream process.

The traveling speed control of the endless belt 20 is performed via a motor 15 driven by a command signal from a control device, and the degree and timing of the acceleration / deceleration can be variously combined depending on conditions such as the position of the feed roll. .
Also, various types of endless belt driving force transmitting means, winding methods, and the like can be considered in relation to the structure. These forms are not limited to the above-described embodiment, and various changes can be made without departing from the gist of the present invention. Further, in the present embodiment, the drive mechanism of the paper feed timing correction device has been described as the synchro belt 17 and the endless belt 20, but these may be driven at a timing, and it is easy to replace them with a chain, for example. .

(Effects of the Invention) As described above, according to the present invention, the dispersion of the paper feed timing, which has been a problem of the conventional paper feeder, is accurately corrected by a straightening device installed downstream, and then the next process. Because it can be transported. Appearance in processing such as printing,
Quality such as accuracy can be improved. Further, there is no need to perform various operations to cope with troubles such as poor printing, and the operation rate of the machine is increased, so that productivity can be improved. Further, according to the present invention, it becomes possible to cope with paperboards of various specifications, and an effect such as expansion of production (product) range can be expected.

Further, by assisting the sheet running for a predetermined time after the sheet is sandwiched between the feed roll and the feed roll,
The load acting on the feed roll can be reduced, and the correction time by the nail (slip time during sheet running) can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view showing a schematic configuration of a paper feed timing correcting apparatus according to the present invention provided in a cardboard sheet box making machine, FIG. 2 is a view for explaining the function (operation timing) of the paper feed section, and FIG.
The figure is a side view of the conventional lead edge type paper feeder.
5 and 5 are explanatory diagrams of a paper feed delay in the conventional paper feeder, and FIG. 6 is an operational timing diagram of the conventional lead edge feeder. Explanation of the main parts in the drawing 1. Front guide 2. Back stop 3. Paperboard (corrugated cardboard sheet) 4. Feeding roll 5. Receiving plate 6. Suction box 7a, 7b Feed roll 8a, 8b … Feed rolls 9a, 9b… Feed rolls 10a, 10b… Feed rolls 11, 12, 13… Pulleys, 14… Synchro pulleys 15… Motors, 16 …… Synchro pulleys 17… Synchro belts, 18… Control device

Claims (1)

(57) [Claims] In a paperboard transport device provided in a cardboard sheet making machine or the like, paperboard stacked on a paper feed table is sent out one by one from a lowermost sheet by a feed roll, and sequentially pinched by a downstream feed roll. Downstream of the paper feeder configured to convey, a conveying means for conveying the sheet at a constant speed, and an endless belt having a paperboard abutting claw fixed to an outer surface within a flow direction range of the conveying means are provided. A feeding timing correcting means for driving the claw portion to be always positioned on a straight line perpendicular to the sheet advancing direction so as to drive the driving, and a driving speed of the timing correcting means is set to a feeding speed of the feeding device. On the other hand, the sheet speed can be corrected without stopping the running of the sheet, and the feeding roll is supported for a predetermined time even after the sheet is clamped by the feed roll. Feed timing correcting device, characterized in that.