JP4516417B2 - Doctor device with mobile doctor blade - Google Patents

Description

  The present invention relates to a doctor device used for scraping off foreign matters such as paper dust adhering to the surface of a roll such as a paper machine roll and a steelmaking roll. More specifically, the present invention relates to a doctor device having a movable doctor blade that is longer than the roll surface length (length in the roll axis direction) and is movable in the roll surface length direction.

  As a doctor device, there is known a device configured to scrape foreign matter adhering to the surface of the roll by pressing the blade edge of the doctor blade against the surface of the rotating roll. Also, in this type of doctor device, if a doctor blade that is sufficiently longer than the roll surface length is used as the doctor blade, and the blade tip that is pressed against the roll surface wears out, the new blade tip presses against the roll surface. Until then, the doctor blade is moved in the roll surface length direction, and the doctor blade is not required to be replaced. For example, it is proposed in Patent Documents 1 and 2.

The movement of the doctor blade is performed by a pair of left and right feed rollers disposed at positions on both sides of the portion of the doctor blade that is pressed against the roll surface. One of the pair of feed rollers is a feed roller to which a driving force is transmitted from a motor or the like, and the other is a pressing roller for pressing the doctor blade against the feed roller. The pressing roller is given a predetermined pressing force by a spring member or a pressing bolt.
Japanese Patent Laid-Open No. 11-247087 JP 2000-334915 A

  Here, the doctor blade is supported in a state in which the doctor blade can move in the longitudinal direction, and is supported in a state in which the blade edge is pressed against the roll surface with a predetermined pressing force. Therefore, a large force is required to move the doctor blade in the roll surface length direction.

  If the nip force between the feed roller and the pressing roller for moving the doctor blade is weak, slippage may occur between the feed roller and the doctor blade, and the doctor blade may not be moved.

  An object of the present invention is to propose a doctor device including a movable doctor blade that can reliably move a doctor blade using a pair of feed rollers.

In order to solve the above-mentioned problem, a doctor device provided with the mobile doctor blade of the present invention,
A doctor blade that has a cutting edge pressed against the roll surface and is longer than the roll surface length;
A blade holding means for holding the doctor blade in a slidable state in the longitudinal direction, and pressing the blade edge of the doctor blade against the roll surface;
Blade conveying means for conveying the doctor blade in the longitudinal direction via a blade holding portion by the blade holding means,
The blade conveying means is
A blade feed roller , and a drive side gear that rotates integrally with the blade feed roller ;
A pressing roller used to press the doctor blade against the outer peripheral surface of the conveying roller , and a driven gear that rotates integrally with the pressing roller ;
A pressing means for sandwiching the doctor blade and pressing the pressing roller against the blade feeding roller;
As the pressing means, the use of air Cylinders,
The drive side gear and the driven side gear mesh with each other.

In the doctor device of the present invention, the pressing roller is pressed using an air cylinder. Therefore, the pressing force can be increased or decreased freely. Therefore, in the case where slippage occurs between the blade feeding roller and the pressing roller and the doctor blade sandwiched between them, the pressing force can be increased unlike the case of the spring member. The doctor blade can be transported without slipping. Further, the pressing force can be adjusted by remote operation via the fluid pressure circuit of the air cylinder without adjusting the screwing amount such as a pressing bolt. Here, it was confirmed that in order to increase the conveying force of the doctor blade by the blade feeding roller and the pressing roller, it is sufficient to increase the pressing force and to drive the blade feeding roller and the pressing roller in synchronization with each other. Therefore, the doctor device of the present invention includes a drive side gear that rotates integrally with the blade feed roller and a driven side gear that rotates integrally with the pressing roller, and the drive side gear and the driven side gear mesh with each other. The blade conveying means is used. Accordingly, the blade feed roller and the pressing roller are rotationally driven in synchronization, and the doctor blade can be conveyed while being sandwiched from both sides by these rollers. Therefore, it is possible to significantly increase the conveying force of the doctor blade as compared with the conventional case where only one of the rollers is rotationally driven. As a result, the doctor blade can be reliably conveyed.

In the doctor device of the present invention, the rotation shaft of the blade feed roller is rotatably held on a first holding plate fixed to the support frame of the blade conveying means, and the rotation shaft of the pressing roller is , Disposed above the rotation axis of the blade feed roller, and held in a freely rotatable state by a second holding plate slidably attached to the support frame up and down by a telescopic rod of the air cylinder. The rotating shaft of the pressing roller can be pressed toward the rotating shaft of the blade feed roller.

  Next, the blade conveying means normally includes a first roller pair and a second roller pair arranged on both sides of the blade holding portion by the blade holding means, and each roller pair is respectively provided with the blade feed roller. And the pressing roller. Further, the pressing means includes a first fluid pressure cylinder that presses the pressing roller of the first roller pair, and a second fluid pressure cylinder that presses the pressing roller of the second roller pair. It is said.

  In this case, the pressing means includes a pressing force adjusting unit that switches the pressing force of each pressing roller by each fluid pressure cylinder to at least a first pressing force and a second pressing force smaller than the first pressing force. It is desirable that the pressing force adjusting unit switch the pressing force of the pressing roller as follows.

  That is, when the doctor blade is transported in the direction from the first roller pair toward the second roller pair, the pressing force of the pressing roller of the second roller pair is set to the first pressing force. Then, the pressing force of the pressing roller of the first roller pair is set to the second pressing force. Conversely, when the doctor blade is transported in the direction from the second roller pair toward the first roller pair, the pressing force of the pressing roller of the first roller pair is changed to the second pressing force. And the pressing force of the pressing roller of the second roller pair is set to the first pressing force.

  By doing so, a tensile force always acting in the conveying direction acts on the portion of the doctor blade held by the blade holding portion, and no slack is generated.

  Next, in order to reduce the conveyance force for conveying the doctor blade, the pressure blade adjustment unit for adjusting the pressure contact force of the blade edge of the doctor blade to the roll surface is provided. The blade edge of the doctor blade is pressed against the roll surface with a first pressure contact force while the doctor blade is stopped without being conveyed, and the first pressure contact is applied while the doctor blade is being conveyed. It is desirable to press the blade edge of the doctor blade against the roll direction with a second pressing force smaller than the force.

  Since the pressure contact force is reduced when the doctor blade is transported, it can be transported easily. Further, when the doctor blade is completely separated from the roll surface, its conveyance becomes very easy, but it is not preferable because the position of the blade holding portion moves and the movement path of the doctor blade is curved. Further, it is not preferable because the doctor blade may come out of the blade holding portion. According to the present invention, it is possible to easily carry the doctor blade without causing such an adverse effect.

As described above, in the doctor device having a movable doctor blade of the present invention, presses the pressing roller using an air Cylinders to be able adjust the nipping force of the feed roller pair for conveying a doctor blade I am doing so. Therefore, these can be pressed with sufficient pressing force so that no slip occurs between the blade feed roller and the doctor blade. Therefore, the doctor blade can be reliably conveyed.

  In the present invention, the blade feed roller and the pressing roller are rotationally driven in synchronization. When the doctor blade is conveyed while being sandwiched from both sides by the rotationally driven roller, it is possible to greatly increase the conveying force of the doctor blade as compared with the conventional case where only one roller is rotationally driven. As a result, the doctor blade can be reliably conveyed.

  Further, in the present invention, when the doctor blade is transported, the pressure contact force against the roll surface of the doctor blade is weakened, so that the doctor blade can be transported smoothly with a small transport force.

  Below, with reference to drawings, the Example of the doctor apparatus provided with the mobile doctor blade to which this invention is applied is described.

  FIG. 1 is an explanatory diagram showing the overall configuration of the doctor apparatus of this example. In this figure, 1 is a doctor device, and 2 is a roll such as a paper machine roll whose surface is doctored by the doctor device 1. The doctor device 1 includes a doctor blade 3 facing the outer peripheral surface of the roll 2, a blade holder 4 that holds the doctor blade 3, and a doctor back 5 that supports the blade holder 4. The doctor back 5 is rotatably supported by brackets 6a and 6b arranged at fixed positions via journals 5a and 5b at both ends thereof. The doctor blade 3 includes a tape-shaped movable doctor blade 31 longer than the roll surface length R, and a holding blade 33 that holds the movable doctor blade 31 in a slidable state in the longitudinal direction. Yes.

  The doctor device 1 further includes a pair of left and right transport units 7L and 7R for transporting the mobile doctor blade 31 and a pair of left and right scissors for scraping off foreign matter adhering to the surface of the mobile doctor blade 31. The doctor devices 8L and 8R and a pair of left and right guide sheaths 9L and 9R for guiding a portion of the movable doctor blade 31 that is drawn outward from the left and right of the holding blade 33 are provided.

  The drive control of the doctor device 1 is performed by the control panel 10. The control panel 10 drives and controls the left and right blade conveyance units 7L and 7R via the driver 11, and conveys the mobile doctor blade 31 in the forward direction FR in the right direction and the backward direction BK in the left direction. Further, drive control of the pneumatic drive portion is performed via the pneumatic circuit 12.

  FIG. 2 is a schematic cross-sectional view of a main body portion of the doctor apparatus 1, and FIG. 3 is a schematic cross-sectional view showing a portion of the doctor blade 3. As shown in these drawings, the doctor blade 3 includes a movable doctor blade 31 having a predetermined length in which a cutting edge 31a pressed against the roll surface 2a is formed on one edge, and the other of the movable doctor blade 31. An insertion portion 32 into which an edge is slidably inserted is constituted by a holding blade 33 formed at the tip. The rear end portion of the holding blade 33 is detachably inserted into an insertion portion 41 (blade holding portion) formed at the tip of the blade holder 4.

  The blade holder 4 includes a top plate 42, finger plates 43 attached to the back surface side at regular intervals, and connecting rods 44 extending through the finger plates. Both ends of the connecting rod 44 are rotatably supported by brackets 53 and 54 fixed to the upper surface of the doctor bag 5. The insertion portion 41 is defined by a tip portion of the top plate 42 and a tip portion of the finger plate 43.

  A bottom plate 55 is attached to the upper surface of the doctor back 5. A pressurizing tube 45 and an opening tube 46 are disposed between the bottom plate 55 and the finger plate 43 of the blade holder 4 with a connecting rod 44 interposed therebetween. ing. These tubes 45 and 46 are connected to the compressed air supply source 48 side via a switching valve 47 in the pneumatic circuit 12. If compressed air is supplied to the pressurizing tube 45 to expand it and the opening tube 46 side is opened to the atmosphere, the blade holder 4 pivots in the direction of pressing the doctor blade 3 against the roll 2 side with the connecting rod 44 as the center. To do. On the contrary, when the pressurizing tube 45 is opened to the atmosphere and compressed air is supplied to the opening tube 46 side, the blade holder 4 turns around the connecting rod 44 in the direction of separating the doctor blade 3 from the roll 2.

  As shown in FIG. 3, the doctor blade 3 includes a mobile doctor blade 31 that is narrow and extremely thin, and a holding blade 33 that is wide. A finger 36 is attached to the surface side of the tip portion 33 a of the holding blade 33 by a mounting bracket 35, and a gap formed between the blade tip portion 33 a and the finger 36 is inserted into the movable doctor blade 31. This is part 32.

  The rear end portion 33b of the holding blade 33 is inserted into the insertion portion 41 formed at the tip portion of the blade holder 4, and is held in a state of being sandwiched from above and below by the portion constituting the insertion portion 41, The spring member 49 is biased. Further, a thin rubber plate 39 is sandwiched between the front end portion of the top plate 42 defining one side of the insertion portion 41 and the inserted holding blade 33. The rubber plate 39 has substantially the same length as the holding blade 33.

  Referring again to FIG. 1, the movable doctor blade 31 is in the form of a tape, and has a length of about 4 to 5 times the surface length R (length in the axial direction) of the roll 2. ing. The movable doctor blade 31 is inserted in a slidable state in the longitudinal direction into an insertion portion 41 (blade holding portion) having a length substantially the same as the roll surface length formed in the blade holder 4. The left and right portions of the movable doctor blade 31 drawn from both ends of the insertion portion 41 are drawn in a symmetrical state. The portion pulled out to the left side (retreat side) BK is introduced into the left blade sheath 9L extending in a substantially orthogonal direction after being drawn straight through the left blade conveyance unit 7L. ing. Similarly, the portion pulled out to the right side (advance side) FR is pulled out linearly via the right side blade conveyance unit 7R, and then curved and extends in a direction substantially orthogonal to the right blade sheath 9R. Has been introduced in.

  The left and right blade sheaths 9L and 9R are respectively provided with blade sensors 13 and 14 for detecting the left and right end portions of the movable doctor blade 31 at the front end side portion and the rear end side portion, respectively. ing. For example, an optical sensor that detects through holes opened in the left and right end portions of the mobile doctor blade 31 is disposed. Outputs of these blade sensors 13 and 14 are supplied to the control panel 10. The control panel 10 controls the conveyance of the mobile doctor blade 31 based on the outputs of the blade sensors 13 and 14.

  FIG. 4 is a schematic configuration diagram of the right scissor doctor device 8R. A scissor doctor device 8R is arranged between the right end of the insertion part 41 of the blade holder 4 and the right blade transport unit 7R, and the scissor doctor between the left end of the insertion part 41 and the left blade transport unit 7L. An apparatus 8L is arranged. Since both have the same structure, the structure of the right scissor doctor device 8R will be described below, and the description of the other scissor doctor device 8L will be omitted.

  The scissor doctor device 8R includes scissor doctor devices 120 and 130 having the same structure disposed on both sides of the mobile doctor blade 31 to be conveyed. These include doctor blades 121 and 131 having a wider width than the movable doctor blade 31, blade holding parts 122 and 132 holding the doctor blades 121 and 131, and doctors supporting the blade holding parts 122 and 132. It has a configuration including backs 123 and 133.

  The blade holders 122 and 132 are provided with pressurizing tubes 124 and 134 and release tubes 125 and 135, respectively, and in the same manner as in the case of the main body portion of the doctor apparatus 1, by expanding and contracting these tubes. The pressure contact force of the doctor blades 121 and 131 with respect to the movable doctor blade 31 can be adjusted.

  Next, FIG. 5 is a schematic diagram showing the configuration of the blade transport unit 7R disposed on the right (forward) FR in the doctor apparatus 1 of this example, and FIGS. 6, 7 and 8 show the blade transport unit. It is a side view, a top view, and a front view showing a specific configuration example of 7R. Referring to these drawings, the blade transport unit 7R includes a blade feeding roller 71 disposed on the lower side and a pressing roller 72 disposed on the upper side with the movable doctor blade 31 interposed therebetween. The pressing roller 72 is pressed against the blade feed roller 71 by a pair of air cylinders 73 and 74 with a predetermined pressing force.

  A drive gear 75 is fixed coaxially to the roller shaft 71a of the blade feed roller 71. A driven gear 76 is also fixed to the roller shaft 72a of the pressing roller 72 in a coaxial state. The drive gear 75 and the driven gear 76 are engaged with each other. The drive gear 75 is rotationally driven by a motor 80 via a transmission mechanism including a pair of sprockets 77 and 78 and a chain 79 spanning them.

  In this example, the blade feed roller 71 and the pressing roller 72 are supported by the support frame 82 attached to the unit base 81 of the blade transport unit 7R. A pair of air cylinders 73 and 74 are mounted downward on the upper surface of the support frame 82. The telescopic rods 73 a and 74 a of the air cylinders 73 and 74 are connected to holding plates 83 and 84 that can slide up and down by a support frame 82. The holding plates 83 and 84 support the roller shaft 72a of the pressing roller 72 in a rotatable state via bearing portions 83a and 84a attached to them. The roller shaft 71a of the lower blade feed roller 71 is supported in a rotatable state by bearing portions 85a and 86a attached to holding plates 85 and 86 fixed to the support frame 82. Further, a motor support base 87 is attached to the unit base 81, and a motor 80 is mounted thereon.

  In addition, a pair of upper and lower scissor doctor devices 8R are attached to the side surface of the support frame 82 facing the main body portion of the doctor device 1. The arcuate blade sheath 9 </ b> R is also supported by a support plate 88 attached to the unit base 81.

  Note that the left blade conveyance unit 7L has the same structure and is arranged symmetrically with respect to the blade conveyance unit 7R. Therefore, the description of the structure is omitted, and the same reference numerals are used when necessary for the description.

(Description of operation)
In the doctor device 1 of this example, for example, it is assumed that the right end portion of the mobile doctor blade 31 is at a position detected by the blade sensor 13. In this state, first, the motor 80 is driven to start the movement of the movable doctor blade 31 in the forward direction FR by the left and right blade conveyance units 7L, 7R. At the same time or before and after this, the left and right air cylinders 73 and 74 are driven to set the pressing force by the pressing roller 72.

  In the case of movement in the forward direction FR, the pressing force of the pressing roller 72 in the right blade transport unit 7R is increased, and the pressing force of the pressing roller 72 in the left blade transport unit 7L is decreased. As a result, the mobile doctor blade 31 moves forward while being held in a predetermined tension state. In the portion of the movable blade holder 31 held by the blade holder 4 (that is, the portion sliding on the insertion portion 41), the blade edge portion is pressed against the roll surface 2a with a predetermined pressure contact force. Yes. Therefore, when the roll 2 rotates, the foreign matter adhering to the surface is scraped off.

  Here, in the blade transport units 7L and 7R of the present example, the blade feed roller 71 and the pressing roller 72 are connected by the drive gear 75 and the driven gear 76, and both are rotationally driven in synchronization. . Compared with the case where the rotational force is transmitted only to one of the rollers, the feeding force by these rollers can be greatly increased. Therefore, the mobile doctor blade 31 can be reliably moved without causing slippage or the like.

  In this example, the pressing force of the pressing roller 72 is generated by the air cylinders 73 and 74. Unlike the case of using a conventional spring member, a holding bolt, etc., it can be adjusted to an arbitrary pressing force, and the adjustment can be remotely operated from the control panel 10 side. Therefore, the movable doctor blade 31 can be reliably moved without slipping, and the pressing force can be easily adjusted.

  Further, during forward movement, the right scissor doctor device 8 </ b> R is held in pressure contact with the movable doctor blade 31. Therefore, the foreign substance adhering to the surface of the movable doctor blade 31 after completion of doctoring and the blade edge portion is removed by the scissor doctor device 8R.

  When the left end of the mobile doctor blade 31 is detected by the blade sensor 13 disposed in the left blade sheath 9L, the forward movement of the mobile doctor blade 31 stops. Thereafter, doctoring is performed while moving the movable doctor blade 31 backward. In this case, the pressing force of the pressing roller 72 in the left blade transport unit 7L is increased, and the pressing force of the pressing roller 72 in the right blade transport unit 7R is decreased. Moreover, the foreign material adhering to the mobile doctor blade 31 is removed by the left scissor doctor device 8L.

  When the right end of the mobile doctor blade 31 is detected by the blade sensor 13 disposed in the right blade sheath 9R, the backward movement of the mobile doctor blade 31 stops. Thus, doctoring is performed while repeating forward and backward movements. When the operation is finished, based on the outputs of the pair of sensors 13 and 14 on both sides, as shown in FIG. 1, both ends of the movable doctor blade 31 are placed in the blade sheaths 9L and 9R. The mobile doctor blade 31 is moved.

  Instead of performing doctoring while being moved, the movable doctor blade 31 may be stopped after moving the movable doctor blade 31 by a predetermined amount, and doctoring may be performed in that state. In this case, during the movement, the pressure contact force of the mobile doctor blade 31 against the roll surface is lowered so that the movement of the mobile doctor blade 31 can be performed smoothly. Just press with force. Further, during doctoring, the pressing force of the left and right pressing rollers 72 is increased, and the portion of the movable doctor blade 31 that is in pressure contact with the roll surface is held in tension.

  Further, as a means for adjusting the pressing force of the pressing roller 72, a device other than the air cylinder can be used. Any mechanism can be used as long as the pressing force is variable and can be operated remotely.

  Furthermore, even when a conventional spring member or holding bolt is used instead of the air cylinder, if the driving gear 75 and the driven gear 76 for driving the feed roller 71 and the pressing roller 72 synchronously are used, The feed force of the mobile doctor blade can be greatly increased.

It is a whole block diagram of the doctor apparatus to which this invention is applied. It is a cross-sectional block diagram of the main-body part of the doctor apparatus of FIG. It is a schematic block diagram which shows the structure of the doctor blade of FIG. It is a schematic block diagram of the scissor doctor apparatus of FIG. It is a schematic diagram of the blade conveyance unit of FIG. It is a side view which shows the example of a specific structure of the blade conveyance unit of FIG. It is a top view of the specific structural example of the blade conveyance unit of FIG. It is a front view of the specific structural example of the blade conveyance unit of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Doctor apparatus 2 Roll 3 Doctor blade 31 Mobile doctor blade 4 Blade holder 5 Doctor back 7L, 7R Blade conveyance unit 8L, 8R Scrape doctor apparatus 9L, 9R Blade sheath 10 Control panel 11 Driver 12 Pneumatic circuit 13, 14 Blade sensor 71 Blade feed roller 72 Presser rollers 73, 74 Air cylinder 75 Drive gear 76 Driven gear 80 Motor

Claims (5)

With a cutting edge pressed against the roll surface, a tape-like doctor blade longer than the roll surface length,
A blade holding means for holding the doctor blade in a slidable state in the longitudinal direction, and pressing the blade edge of the doctor blade against the roll surface;
Blade conveying means for conveying the doctor blade in the longitudinal direction via a blade holding portion by the blade holding means,
The blade conveying means is
A blade feed roller , and a drive side gear that rotates integrally with the blade feed roller ;
A pressing roller used to press the doctor blade against the outer peripheral surface of the blade feed roller , and a driven gear that rotates integrally with the pressing roller ;
A pressing means for sandwiching the doctor blade and pressing the pressing roller against the blade feeding roller;
As the pressing means, the use of air Cylinders,
A doctor apparatus comprising a movable doctor blade, wherein the drive side gear and the driven side gear mesh with each other . In claim 1,
The rotation axis of the blade feed roller is rotatably held by a first holding plate fixed to a support frame of the blade conveying means,
The rotating shaft of the pressing roller is disposed above the rotating shaft of the blade feed roller and is rotatably held by a second holding plate that is slidably attached to the support frame. ,
A doctor apparatus comprising a movable doctor blade , wherein a rotating shaft of the pressing roller is pressed toward a rotating shaft of the blade feed roller by an extendable rod of the air cylinder . In claim 1 or 2,
The blade conveying means is
A first roller pair and a second roller pair disposed on both sides of the blade holding portion by the blade holding means, each roller pair including the blade feed roller and the pressing roller;
The pressing means is
A first fluid pressure cylinder that presses the pressing roller of the first roller pair;
And a second fluid pressure cylinder that presses the pressing roller of the second roller pair. In claim 3,
The pressing means includes a pressing force adjusting unit that switches the pressing force of each pressing roller by each fluid pressure cylinder to at least a first pressing force and a second pressing force smaller than the first pressing force. ,
The pressing force adjustment unit is
When conveying the doctor blade in the direction from the first roller pair toward the second roller pair, the pressing force of the pressing roller of the second roller pair is set to the first pressing force, The pressing force of the pressing roller of the first roller pair is set to a second pressing force;
When conveying the doctor blade in the direction from the second roller pair toward the first roller pair, the pressing force of the pressing roller of the first roller pair is set to a second pressing force, A doctor device comprising a movable doctor blade, wherein the pressing force of the pressing roller of the second roller pair is set to a first pressing force. In claim 1,
A pressing force adjusting portion for adjusting the pressing force of the blade edge of the doctor blade to the roll surface;
The pressure contact force adjuster is
While the doctor blade is stopped without being conveyed, the blade edge of the doctor blade is pressed against the roll surface with a first pressing force,
While the doctor blade is being conveyed, the doctor equipped with the mobile doctor device is characterized in that the blade edge of the doctor blade is pressed against the roll direction with a second pressing force smaller than the first pressing force. apparatus.

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