JPS62251139A - Doctor device for printing press - Google Patents

Abstract

PURPOSE:To set a doctor distance and a doctor angle to constantly fixed values, by providing a device for detecting the position of a support arm and relative positions of a support member and a doctor holder, and calculating and displaying a doctor distance and a doctor angle which are set on the basis of the circumference of a form cylinder inputted. CONSTITUTION:A pulse signal for calculating the position of the center of rotation of a box 17 is sent from a rotary encoder 51 to a operational controller 62. The controller 60 calculates a doctor distance and a doctor angle, and displays them on a display device 62. When the displayed values are not equal to desired values, the controller 60 again moves an arm 4 or a doctor holder 19. When the desired doctor distance and doctor angle are obtained, the doctor 19 is fixed to the box 17. The front edge of a doctor blade 18 is pressed against a form cylinder 2 with an appropriate pressure, and printing is conducted under desired doctor conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a doctor device for a printing press that is capable of displaying the distance and angle of the doctor relative to the plate cylinder.

(Technical background) A doctor device such as a gravure printing machine is used to scrape off ink coated on the plate cylinder by pressing the tip of the doctor blade held by the doctor holder against the plate cylinder. Settings have an important effect on print quality, and in order to always obtain constant print quality, it is necessary to keep the doctor setting conditions constant. In other words, the doctor distance, which is the distance from the contact point of the impression cylinder to the tip of the doctor blade on the circumference of the plate cylinder, and the doctor angle formed by the circumferential surface of the plate cylinder and the doctor blade are This doctor distance and doctor angle must always be kept constant in order to always obtain constant printing quality, since they affect the degree of scraping and the degree of ink transfer to the printing sheet.

On the other hand, the circumference of plate cylinders used in gravure printing machines and the like changes significantly depending on the type of printed material, so it is necessary to reconfigure doctor conditions such as doctor distance and angle each time the plate cylinder circumference changes. Conventionally, this work of setting doctor conditions has relied on the experience and intuition of the operator. That is, the doctor blade tip is moved to a desired position by manually operating various adjustment mechanisms provided on the doctor device to move the doctor holder vertically or horizontally.

FIG. 8 is a schematic diagram showing the adjustment mechanism of a general doctor device. As shown in the figure, the doctor device 100 has a support shaft 1
01, the support shaft 101 is composed of a support member lO2, a lead screw 103, a moving member 104, a rotating shaft 105, a holding member 106, etc., and the support shaft 101 is rotatably supported at both ends by a printing press frame (not shown). 102 is supported non-rotatably, and the lead screw 1 is attached to the support member 102.
03 is rotatably attached, and the lead screw 103
A moving member 104 is engaged with the moving member 104, a holding member 106 is rotatably supported by the moving member 104 via a rotating shaft 105, and a doctor holder 107 holding a doctor blade 108 is held horizontally on the upper surface of the holding member 106. It is held so that it can slide in the direction. The adjustment mechanism of this doctor device 100 is composed of a vertical adjustment mechanism tube 1, a swing mechanism M2, a sliding mechanism M3, and a swinging mechanism t1M4. The swing mechanism M2 rotates a handle (not shown) attached to one end of the support shaft 101 to rotate the entire doctor device 100. , the sliding mechanism M3 moves the doctor holder 107 in the horizontal direction using a screw mechanism (not shown) provided between the holding member 106 and the doctor holder 107, and the swinging mechanism M4 moves the doctor holder 107 in the horizontal direction using a screw mechanism (not shown) provided between the holding member 106 and the doctor holder 107. The holding member 106 is rotated about the rotating shaft 105 by an adjustment mechanism (not shown) provided between the holding members 106.

In such a doctor device 100, the plate cylinder 110
The position and angle of the doctor blade 108 relative to
It can be arbitrarily adjusted by operating each of the mechanisms M1, M2, M3 and M4. However, since there are many adjustment elements and the movement is complicated, it not only takes time to set the doctor distance and doctor angle when the circumference of the plate cylinder 110 changes, but also it is necessary to always maintain a constant doctor distance and doctor angle. The problem was that it was almost impossible.

As an improvement to the above-mentioned doctor device, in order to reduce various adjustment elements, simplify the mechanism, and effectively utilize the space below the plate cylinder, various support mechanisms and adjustment mechanisms are provided at the top of the plate cylinder. A doctor device of the type shown in FIG.

However, even with the above-mentioned hanging type doctor device, the reality is that setting the doctor distance and doctor angle conditions relies on the experience and intuition of the operator, and not only does it take a long time to set the conditions, but it also takes a long time. There is no means to check the doctor distance and angle that have been set, and the conditions cannot always be set to a constant value, resulting in a problem that a constant print quality cannot be obtained.

(Object of the Invention) The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to set certain doctor conditions by displaying the set doctor distance and doctor angle in a hanging doctor device. The purpose is to provide a device that can.

(Summary of the Invention) To achieve this object, the present invention includes a pair of holding arms suspended from above on both sides of the plate cylinder, a support member rotatably held at the lower end of the holding arms, and a support member that is rotatably held at the lower end of the holding arms, and a doctor holder held by the supporting member so as to be able to slide in the direction of moving toward and away from the doctor holder; a lifting device that raises and lowers the holding arm so that the center of rotation of the support member moves on a straight line inclined with respect to the vertical direction; and a first device that detects the position of the holding arm from the plate cylinder. a second position detecting device for detecting the relative position of the support member and the doctor holder, an input device for inputting the circumference of the plate cylinder, the first position detecting device and the first position detecting device; Based on the signal from the second position detection device and the input from the input device, calculate the doctor distance on the circumference of the plate cylinder and the doctor angle formed by the doctor blade and the circumferential surface of the plate cylinder. The present invention provides a doctor device for a printing press, comprising: a calculation control device that performs calculations; and a display device that displays the doctor distance and doctor angle based on the calculation results of the calculation control device.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 2 is a front view of a doctor device showing an example of the present invention, and FIGS. 3, 4, 5, and 6 are respectively ut of FIG.
-m, IV-IV, V-V and Vl-Vl arrow views.

In FIG. 2, a doctoring device 1, which represents an embodiment of the invention, has a pair of holding arms 4.4 arranged along the machine frame 3.3 on either side of the plate cylinder 2. In FIG. Holding arm 4
．． 4 has a groove 4A on the side surface, and the groove 4A engages with a protrusion 5A of a guide member 5 fixed to the frame 3 at an angle with respect to the vertical direction, as shown in FIGS. 3 and 4. . The holding arm 4 is thus able to slide up and down along the guide member 5. The holding arm 4 furthermore has a rack 6 in which a pinion 8 is engaged, which is mounted on a rotating shaft 7 which is rotatably mounted on the frames 3.3 on both sides.

The rotating shaft 7 is driven by a motor 5o via a reducer (not shown), and by rotating the motor 50, the pair of holding arms 4.4 simultaneously move on a straight line inclined in the vertical direction. Move up and down. Further, a rotary encoder 51 is connected to the motor 50. In addition, the rotating shaft 7
The driving is not limited to being performed by the motor 50 as described above, but may be performed by rotating a manual handle via a worm wheel, a worm, or the like.

A bearing block 10 is fixed to the lower end of the holding arm 4,
The bearing block 10 rotatably holds the support shaft 11, as best seen in FIG. A worm wheel 12 is fixed to a support shaft 11 near one of the holding arms 4, and a housing 13 rotatable with respect to the support shaft is arranged around the worm wheel 12. The housing 13 holds an adjustment shaft 15 having a worm 14 that engages with the worm wheel 12, and by turning the adjustment shaft 15, the support shaft 11 is rotated, and the angular position of the support shaft 11 with respect to the housing 13 can be adjusted. A lever 13A is formed in the housing 13, and one end thereof is connected to a piston rod of a fluid pressure cylinder (for example, a pneumatic cylinder) 16 connected to the holding arm 4. The fluid pressure cylinder 16 acts to apply torque to the housing 13 and press the tip of the doctor blade held on the support shaft 11 against the plate cylinder 2 with appropriate pressure, as will be described later.

Referring to FIGS. 5 and 6, the support shaft 11 is covered with a box 17 along almost its entire length. This box 17 is held non-rotatably but slidably in the axial direction relative to the support shaft 11 by linear bearings 20.21. A hole 11A is formed at the end of the support shaft 11, and the drive rod 22 inserted into the hole is connected to the box 17 via a connecting bolt 23. The drive rod 22 is reciprocated by an external drive (not shown), which causes the box 17 and doctor blade to reciprocate transversely to the plate cylinder. A ring 24 and a tube 25 are attached to the end of the box 17, while a tube 26, which is slightly larger than the tube 25, is also attached to the housing 13. The cylinder 25 is inserted into the cylinder 26 to prevent surrounding ink and dirt from entering.

The upper surface of the box I7 forms the sliding surface of the doctor holder 19 that clamps and fixes the doctor blade 18.
A corner member 30 provided with a screw hole is fixed to the end thereof. A rod 29 having a threaded portion is engaged with the corner member 30, one end of the rod 29 is rotatably fitted into a groove (not shown) provided in the doctor holder 19, and a grip 27 is attached to the other end. A slide member 53 is rotatably fitted in the central portion of the doctor holder 19. The slide member 53 is connected to a potentiometer 52 provided inside the upper part of the box 17. Therefore, by rotating the grip 27, the rod 29 moves, the doctor holder 19 slides on the box F, the slide member 53 moves, and the relative position of the doctor holder 19 with respect to the box 17 is detected by the potentiometer 52. Can be done. This grip 27,
A doctor holder sliding mechanism composed of a rod 29 and a corner member 30 is provided at both ends of the box 17 in the longitudinal direction, and adjusts the horizontal position of the doctor blade and balances the plate cylinder 2 in the axial direction. . Further, the doctor holder 19 is provided with a notch (not shown), and a fixing member 31 that passes through this notch and engages with the box 17 connects the doctor holder 19 and the box 17.
are tightened and fixed. In addition, 28 in Fig. 6 is a handle,
This is used when removing the doctor holder 19 from the box 17.

FIG. 1 is a schematic diagram showing an example of a device for displaying doctor distance and doctor angle according to the present invention. As shown in the figure, a rotary encoder 51, a plate cylinder circumference input device 61, and a potentiometer 52 via a signal converter 53 are connected to the input side of the arithmetic and control device 60, and the doctor distance and angle are displayed on the output side. A display device 62 and a recording device 63 for recording calculation results of the calculation control device 60 are connected.

The plate cylinder circumference input device 61 is composed of a keyboard or numeric keypad, etc., and is designed to directly input the plate cylinder circumference value.The display device 61 is composed of a CRT, liquid crystal display, meter, etc., and is a recording device. 63 is composed of various printers and the like. The arithmetic control device 60 receives a pulse signal given from the rotary encoder 51, a signal given from the signal converter 53, and a plate cylinder circumference input device 6.
1, and outputs the doctor distance S and the doctor angle θ4.

Next, the operation of the above device will be explained together with the operation of setting doctor conditions.

First, the holding arm 4 is returned to the original position in advance. This origin position is normally set at the upper end position of the holding arm 4.

After plate cylinder replacement and other printing preparations are completed, the circumference value of the newly centered plate cylinder is input from the plate cylinder circumference input device 61. This input circumference value of the plate cylinder is stored in the storage section of the arithmetic and control unit 60. Next, the motor 50 is operated by operating an operation button (not shown) installed on the machine frame or the like.
is rotated, the holding arm 4 is lowered from the original position, and the center of rotation of the box 17 is moved to an appropriate position near the plate cylinder 2. At this time, a pulse signal for calculating the amount of movement of the holding arm 4, that is, the position of the center of rotation of the box 17, is sent from the rotary encoder 51 to the arithmetic and control unit 6.
2 is input. Next, after releasing the fastening of the fixing member 31 and making the doctor holder 19 freely slidable,
The grips 27 provided on both longitudinal sides of the box 17 are rotated to move the doctor holder 19 to an appropriate position. At this time, a signal for calculating the position of the tip of the doctor blade 18 with respect to the center of rotation of the box 17 is input from the potentiometer 52 to the arithmetic and control unit 60 via the signal converter 53.

Here, by operating a calculation start key or the like (not shown) provided on the calculation and control device 60, the calculation and control device 60 starts calculation processing and calculates each data of the doctor distance S and the doctor angle θ4. Then, the display device 62 displays the doctor distance S and the doctor angle θ4 based on the calculation results of the calculation and control device 60. If the displayed doctor distance and doctor angle are not the desired values, move the arm 4 or doctor holder 19 again, and set the doctor distance S and doctor angle θd after the movement to the calculation control bag W.
60 and displayed on the display device 62.

When the desired doctor distance and doctor angle are obtained by moving the arm 4 or the doctor holder 19 in this way, the fixing member 31 is tightened and the doctor holder 19 is moved.
is fixed in box 17. Next, the adjustment shaft 15 is turned to bring the tip of the doctor blade 18 into contact with the rotating plate cylinder 2, and the fluid pressure cylinder 16 is actuated to press the tip of the doctor blade 18 against the plate cylinder 2 with an appropriate pressure, and the printing sheet (Fig. By pressing the plate (not shown) against the plate cylinder 2 with an impression cylinder (not shown), printing is performed under desired doctor conditions.

In addition, if the arm 4 or doctor holder 19 is moved to change the doctor distance or doctor angle during test printing or printing after setting the doctor distance and doctor angle to certain values, the doctor distance after the change will be and the doctor angle are calculated by the arithmetic control device 60 and displayed on the display device 62, and the recording device 63
By recording this information, it is possible to obtain data for setting doctor conditions when printing using the same plate cylinder later.

Next, calculation of the doctor distance and doctor angle in the arithmetic and control device 60 will be explained.

FIG. 7 shows the positional relationship among the plate cylinder 2, box 17, and doctor blade 18. As shown in the figure, the position of each part is expressed in x-y coordinates with the center of the plate cylinder as the origin 0, point P1 is the intersection of the circumference of the plate cylinder 2 and the y-axis, and point P2 is the intersection of the circumference of the plate cylinder 2. Contact point between the circumference and the doctor blade 18, point P3
is the center of rotation of the box 17, point P4 is the intersection of the extension line of the doctor blade and a line passing through point P3 and perpendicular to this extension line, and straight line H is a line parallel to the X axis passing through point P2. The locus of the point P3 when the arm 4 moves up and down, the straight line T, is a tangent at the point P2. In this case, the doctor distance S
is the length of the arc PIP2, and the doctor angle θ4 is the angle between the doctor blade 18 and the tangent T.

Here, the coordinates of each point, the angle formed by each straight line, and the distance between each point and each straight line are expressed as follows.

P2 (x, y), P3 (X, Y) α: Angle β between doctor blade 18 and straight line P2P3: Straight line K
Angle θ1 between the line OP2 and the y-axis: Angle θ2 between the straight line OP2 and the y-axis: Angle β between the doctor blade 18 and the straight line H.

: Distance between points P2 and P4 12 : Distance between points P2 and P3 13 : Distance from the origin O to the straight line At this time, since the circumference of the plate cylinder 2 is If it is r, then r= (L/2π), and X=x+1. cos(θ2−α) −■Y=y+
Il, 5in(02-α) -■(tanshi x=rsinθ, ,y=r cosθsummer,y
The slope of the straight line with respect to the axis is θ4−θ2+θ1 from β
-■ From the above formulas ■, ■, ■ and 0, the formula for calculating the doctor distance S and the doctor angle θ6 is as follows.

S−rθ1 −■θ4−α+θ
1 A'= (1+a")Y"+2bY+a"r"+b"
-a” j! +B = 2ar(b+Y) C=2a”rY 10 = R, cosα r = L / 2π a = 1/lanβ b = It 2 / sinβ Here, the y-coordinate Y of the center of rotation of box 170 is the rotary The doctor blade 1 in the moving direction of the doctor holder 19 is calculated based on the number of pulses from the encoder 51.
The distance He between the tip of 8 and point P4.

is calculated from the detected value of the potentiometer 52, and
The circumference of the circle is input from the plate cylinder circumference input device 61.

Therefore, by storing in advance in the arithmetic and control unit 60 the inclination β of the straight line forming the trajectory of the center of rotation of the box 17 and the distance 7!2 between the straight line and the center of the plate cylinder 2, Y, 7! . And based on the value of L, the above ■, 0
The doctor distance S and the doctor angle θ4 are calculated from the formula.

(Effects of the Invention) As described above, the present invention is provided with a position detection device for detecting the position of the holding arm and the relative position of the supporting member held by the holding arm and the doctor holder in a hanging type doctor device. The doctor distance and doctor angle set based on the entered plate cylinder circumference are calculated and displayed, so it is impossible to set the doctor distance and doctor angle to a constant value because it relies on the operator's experience and intuition. The distance and angle can always be set to constant values, resulting in the effect that constant print quality can be obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an example of a device for displaying doctor distance and doctor angle in the present invention, FIG. 2 is a front view of a doctor device showing an example of the present invention, and FIG. Fig. 4 is a view from IV-IV in Fig. 2, Fig. 5 is a view from V-V□ in Fig. 2, and Fig. 6 is a view from Fig. 2 in Fig. 2.
7 is an explanatory diagram of the doctor distance and doctor angle calculation by the arithmetic and control unit 60 shown in FIG. 1, and FIG. 8 is a schematic diagram showing the adjustment mechanism of a general doctor device. It is. 1... Doctor device 2... Plate cylinder 3... Frame 4... Holding arm 5... Guide member 7... Rotating shaft 10... Bearing block 11... Support shaft 17...・Box 1 day... Doctor blade 19... Doctor holder 50... Motor 51... Rotary encoder 52... Potentiometer L... Plate cylinder circumference S... Doctor distance θ,... Doctor Angle Patent Applicant Dai Nippon Printing Co., Ltd. Agent Patent Attorney Atsushi Konishi 3 Figure 4 Figure 5 Figure 6 Figure 7 I! 0

Claims (1)

[Scope of Claims] A pair of holding arms suspended from above on both sides of the plate cylinder; a support member rotatably held at the lower end of the holding arms; and a support member that slides in directions toward and away from the plate cylinder. a pressure device that applies torque to the support member and presses the tip of the doctor blade held by the doctor holder against the circumferential surface of the plate cylinder; a lifting device that raises and lowers the holding arm so that the center of rotation moves on a straight line inclined with respect to the vertical direction; a first position detection device that detects the position of the holding arm from the plate cylinder; and the support. a second position detection device that detects the relative position of the member and the doctor holder; an input device that inputs the circumference of the plate cylinder; and signals from the first position detection device and the second position detection device. and an arithmetic control device that calculates a doctor distance on the circumference of the plate cylinder and a doctor angle formed by the doctor blade and the circumferential surface of the plate cylinder based on input from the input device; A doctor device for a printing press, comprising: a display device that displays the doctor distance and doctor angle based on calculation results of a control device.