JP2019155541A - Belt sanding machine - Google Patents

Abstract

To simplify compared to a conventional constitution, a belt sanding machine which includes a polishing device capable of selectively pressing a polishing belt to a workpiece by a plurality of tread pressure heads.SOLUTION: A rotary holder 30 is pivoted to the inside of a polishing belt 25 so as to make rolls 22-24 wound with the polishing belt 25 and a rotation axis parallel, and a plurality of tread pressure heads 31-34 are attached to the periphery of the rotation center of the rotary holder 30. The rotary holder 30 is rotatably driven by a holder rotational mechanism, and the respective tread pressure heads 31-34 hold the rotary holder 30 in a rotation position opposite to a conveyance passage 8 of a workpiece W. The rotary holder 30 is driven to advance/retreat toward the conveyance passage 8 by a holder advance/retreat mechanism together with the holder rotational mechanism so as to change the tread pressure head 31 opposed to the conveyance passage 8 to a retreat position retreating to the inside of the polishing belt 25, and an extrusion position of pressing the polishing belt 25 to the conveyance passage 8 side.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a belt sander machine that conveys a workpiece along a conveyance path and polishes the workpiece by a polishing apparatus disposed in the vicinity of the conveyance path.

  2. Description of the Related Art A belt sander machine is known in which a workpiece is conveyed along a conveyance path and the workpiece is polished by a polishing apparatus disposed in the vicinity of the conveyance path. Specifically, the polishing apparatus of the belt sander machine is configured to press and polish an endless polishing belt that is wound around a plurality of rolls against a workpiece that passes through a conveyance path from the inside. In such a polishing apparatus, a configuration is proposed in which multiple types of pressure heads are provided inside the polishing belt, and the polishing belt can be pressed against the workpiece using a pressure head suitable for the properties and processing conditions of the workpiece. (For example, refer to Patent Document 1).

JP 2007-105858 A ([0022] to [0023], FIGS. 7 and 9)

  By the way, in the belt sander described in Patent Document 1, a plurality of types of pressure heads are retracted from the inner peripheral surface of the polishing belt, and only the pressure pressure heads to be used are directed to the polishing belt by an air cylinder (press shifter). It is configured to advance. For this reason, in the polishing apparatus described in Patent Document 1, an air cylinder is required for each treading head, and the structure of the polishing apparatus is complicated.

  The present invention has been made in view of the present situation, and an object thereof is to simplify a belt sander machine including a polishing apparatus capable of selectively using a plurality of treading heads as compared with a conventional configuration.

  The present invention provides a belt sander machine provided with a polishing device that is disposed in the vicinity of a conveyance path through which a workpiece is conveyed, and that polishes by pressing an endless polishing belt wound around a plurality of rolls against the workpiece by a treading head. The polishing apparatus is provided with a plurality of treading pressure heads around a rotation center, and is supported on the inner side of the polishing belt so that the plurality of rolls and a rotation axis are substantially parallel, and A rotary holder held so as to be able to advance and retreat toward the transport path, and the rotary holder can be driven to rotate, and the rotary holder can be held at a rotational position where each of the tread heads faces the transport path. By driving the holder rotating mechanism and the rotating holder and the holder rotating mechanism forward and backward toward the transport path, the stepping pressure head facing the transport path is polished. A retracted position retracted inside the belt, a belt sander machine of the grinding belt, characterized in that it comprises said conveying path convertible holder advance and retreat in a pushing position for pushing the side mechanism.

  In the belt sander machine of the present invention, an arbitrary treading pressure head can be made to face the conveyance path by rotationally driving the rotary holder by the holder rotating mechanism. Then, by moving the rotary holder and the holder rotation mechanism to the conveyance path side by the holder advance / retreat mechanism and converting the stepping pressure head opposed to the conveyance path to the extrusion position, the polishing belt is pressed against the workpiece with the stepping head. Can be polished. In such a configuration, since the plurality of stepping pressure heads are driven forward and backward with respect to the conveyance path by the holder advance / retreat mechanism, only one set of mechanisms for moving the stepping pressure heads back and forth is sufficient regardless of the number of the stepping pressure heads. Therefore, according to the present invention, it is possible to simplify the configuration of the polishing apparatus including a plurality of tread heads. In the present invention, other stepping pressure heads that are not opposed to the conveyance path are also driven forward and backward together with the rotary holder, but the other stepping pressure heads are retracted to the near side of the stepping pressure head that is opposed to the conveyance path. Therefore, it does not interfere with the polishing belt or workpiece.

  In the present invention, it is proposed that the holder advance / retreat mechanism is a ball screw actuator.

  With such a configuration, it is possible to press the polishing belt against the workpiece with a force suitable for the hardness and shape of each stepping pressure head without providing an advance / retreat mechanism for each stepping pressure head. If the holder rotation mechanism is composed of an air cylinder, the rotation holder can be stopped only at two points, the start point and end point of the cylinder. Therefore, it is difficult to adjust the advancement amount for each treading head. This is because if the screw actuator is used, the advancement amount of the rotary holder can be finely adjusted in accordance with the stepping pressure head facing the conveyance path.

  In the case of the above configuration, the rotational position of the rotary holder is controlled via the holder rotating mechanism so that the required pressure head is opposed to the transport path, and the rotary holder is placed in the transport path. A control device that controls the holder advancing / retreating mechanism so as to advance toward the forward direction and converts the stepping pressure head from the retracted position to the push-out position, and the control device advances the rotary holder toward the conveyance path. The advance amount can be set for each of the pressure heads, and when the pressure head is converted from the retracted position to the push-out position, the holder advance / retreat mechanism is controlled so that the rotary holder is attached to the pressure head. It is proposed to advance toward the conveyance path by a corresponding advance amount.

  In such a configuration, the advancement amount of the rotary holder is set in advance for each stepping pressure head, so that the operation of setting the advancement amount of the rotation holder becomes unnecessary every time the stepping pressure head is switched.

  In the above configuration, at least one of the plurality of treading pressure heads includes a pad holding fitting attached to the rotating holder, an elastic pad attached to a tip portion of the pad holding fitting, and the elastic pad. A pad-type treading head that presses the polishing belt from the inside toward the conveyance path side with the elastic pad covered with the wear-resistant sheet. The elastic pad of the pad-type treading head has a layer structure, and a support layer made of a soft elastic material is provided on the base end side of the elastic pad, and the support layer is provided at a distal end portion of the elastic pad. It is proposed that a pressing layer made of a hard elastic material is provided. Here, the soft elastic material includes a sponge, and the elastic material harder than the soft elastic material includes rubber.

  When a flat surface of a workpiece is polished by a belt sander machine, the polishing belt is generally pressed by a treading pressure head having a hard elastic pad. Here, as described above, the configuration in which the rotary holder is advanced and retracted by the ball screw actuator is inferior to the cushioning property that absorbs the force applied to the treading head as compared with the case of being advanced and retracted by the air cylinder. When pressing, the familiarity between the surface of the workpiece and the elastic pad tends to deteriorate. On the other hand, if it is the said elastic pad which arrange | positions a soft support layer in the base end side of a press layer, when a support layer exhibits cushioning properties, a comparatively hard press layer is formed on the surface of a workpiece | work. You can get used to it. Therefore, if a pad type tread head having such an elastic pad is mounted on a rotary holder that is driven forward and backward by a ball screw actuator, the flat surface of the workpiece can be properly polished.

  Further, in the present invention, at least one of the plurality of treading pressure heads includes a pad holding fitting that is attached to the rotating holder, an elastic pad that is detachably attached to a tip portion of the pad holding fitting, and the elastic pad. A pad-type stepping pressure head that presses the polishing belt from the inside toward the conveyance path side with the elastic pad covered with the wear-resistant sheet. The elastic pad of one of the pad type treading heads has a two-layer structure including a first layer made of a soft elastic material and a second layer made of a hard elastic material compared to the first layer, A mode in which the first layer is disposed on the front end side of the elastic pad with respect to the pad holding metal fitting, and a second layer is arranged on the front end side of the elastic pad with respect to the pad holding metal fitting. The The mode of wear, it is proposed that is mountable in at least two aspects.

  In such a configuration, one treading pressure head can be used in two types depending on the direction in which the elastic pad is mounted, so that the cost can be reduced.

  As described above, according to the present invention, a belt sander machine including a polishing apparatus that can selectively use a plurality of treading heads can be simplified as compared with the conventional configuration.

It is a top view of the belt sander machine 1 of an Example. 3 is an enlarged side view of the belt sander machine 1 showing a peripheral portion of the polishing apparatus 3. FIG. 3 is a plan view of the polishing apparatus 3. FIG. FIG. 3 is a side view showing the internal structure of the polishing apparatus 3 with the casing 20 and the like omitted. It is explanatory drawing which shows the state which hold | maintained the rotation holder 30 in each reference | standard rotation position. It is explanatory drawing which shows the state (a) holding the treading pressure head 31 in the retracted position, and the state (b) held in the advanced position. It is explanatory drawing which shows the state which converted each treading pressure heads 31-34 into the extrusion position in each reference | standard rotation position of the rotation holder 30. FIG. They are a side view (a) and a plan view (b) of the pad type treading heads 31 and 32. It is a side view of the roll type treading pressure heads 33 and.

  Embodiments of the present invention are described according to the following examples.

  Drawing 1 is a top view of belt sander machine 1 of an example. Such a belt sander machine 1 is used for polishing a side edge of a wooden board. In the following description, the left side in FIG. 1 is described as the left side of the belt sander machine 1, and the lower side in FIG. 1 is described as the front side of the belt sander machine 1.

  The belt sander machine 1 includes a transport device 2 that transports a workpiece W (wood plate material). The conveying device 2 includes a roller conveyor 6 and a guide rail 7 installed on a base 5, and the upper side of the roller conveyor 6 is a conveyance path 8 in the left-right direction for conveying the workpiece W. A polishing device 3 for polishing the workpiece W is disposed in the vicinity of the back surface side of the conveyance path 8. A control device (not shown) for controlling the transport device 2 and the polishing device 3 is disposed inside the base 5, and an operation panel 4 is disposed above the base 5.

  The roller conveyor 6 is rotationally driven by a workpiece transfer motor (not shown) so as to transfer the workpiece W mounted on the transfer path 8 from right to left. The guide rails 7 are formed on the left and right along the back side of the transport passage 8. The conveyance direction of the workpiece W by the roller conveyor 6 is slightly inclined to the back side with respect to the direction of the guide rail 7, so that the workpiece W conveyed by the roller conveyor 6 through the conveyance path 8 is side edge on the back side. Is positioned so as to pass through the conveyance path 8 while sliding on the guide rail 7.

  The polishing apparatus 3 includes one endless polishing belt 25. As shown in FIG. 1, the polishing belt 25 is exposed to the front end side (front side) of the polishing apparatus 3, and the center portion on the front end side presses the polishing belt 25 against the work W to polish the work W. It becomes the grinding | polishing part 11 to do. A gap 10 is formed in the guide rail 7 at an intermediate position of the conveyance path 8, and the polishing apparatus 3 is arranged on the back side of the conveyance path 8 so that the polishing unit 11 faces the conveyance path 8 from the gap 10. Is done. As shown in FIG. 2, the polishing apparatus 3 is installed horizontally on the lifting platform 14. The lifting platform 14 includes a lifting frame 15 on which the polishing apparatus 3 is mounted, a screw jack 16 that lifts the lifting frame 15, and a lifting guide 17 that is attached to the base 5 and moves the lifting frame 15 up and down. The The polishing table 3 is held by the lifting platform 14 so that the center of the workpiece W passing through the conveyance path 8 and the center of the polishing unit 11 are at the same height.

  As shown in FIGS. 3 and 4, the polishing apparatus 3 includes a metal housing 20 that opens upward. Three rolls 22 to 24 are axially supported in the inside of the casing 20, and the endless polishing belt 25 is wound in a substantially triangular shape so as to be fitted around these rolls 22 to 24. It has been. Of the three rolls 22 to 24, one roll 22 disposed on the back side is a drive roll driven by a polishing motor 26 directly below, and two rolls disposed on both sides of the tip portion. These rolls are idleable guide rolls 23 and 24. The polishing belt 25 travels around the three rolls 22 to 24 in the counterclockwise direction in FIG. 3 by being driven by the rotation of the drive roll 22. A portion of the polishing belt 25 that travels in the left-right direction between the two guide rolls 23 and 24 is disposed in the polishing unit 11. The drive roll 22 is urged to the back side by the air cylinder 28 in order to apply tension to the polishing belt 25. The polishing belt 25 is formed by endlessly forming a sandpaper for wood processing. The outer peripheral surface is a polished surface to which an abrasive is attached, and the inner peripheral surface is a smooth surface to which no abrasive is attached. ing. As the polishing belt 25, a polishing belt of an existing belt sander machine can be appropriately used.

  As shown in FIGS. 3 and 4, a rotary holder 30 to which four types of treading pressure heads 31 to 34 are mounted is disposed inside the housing 20 of the polishing apparatus 2. The rotary holder 30 is a metal member having a cross shape in plan view, and stepping pressure heads 31 to 34 are mounted one by one on the four rotary arm portions 30b extending in four directions from the central portion 30a. The treading pressure heads 31 to 34 push the polishing belt 25 from the inside toward the conveyance path 8 and press the polishing belt 25 against the work W. As will be described later, of the four treading pressure heads 31 to 34, two are pad type treading pressure heads 31 and 32, and the remaining two are roll type treading pressure heads 33 and 34.

  The rotary holder 30 is axially supported inside the polishing belt 25 so as to be horizontally rotatable around the central portion 30a as a center of rotation, and is rotated by a holder rotating mechanism disposed in the polishing apparatus 3. Further, the rotary holder 30 is held inside the polishing belt 25 so as to be able to advance and retreat toward the conveyance path 8, and is driven forward and backward by a holder advance / retreat mechanism 49 provided in the polishing apparatus 3.

  The holder rotating mechanism rotates and drives the rotating holder 30, and the four pressure positions (hereinafter referred to as “reference rotation”) in which the treading pressure heads 31 to 34 are positioned in the polishing unit 11 and face the front conveyance path 8. The rotation holder 30 can be held at a position. That is, as shown in FIG. 5, the treading pressure heads 31 to 34 located in the polishing unit 11 can be switched by rotating and stopping the rotating holder 30 by the holder rotating mechanism.

Specifically, as shown in FIG. 4, the holder rotating mechanism includes a cam clutch 40 that holds the rotating holder 30 so as to be rotatable only in a clockwise direction in plan view, a rotary actuator 41 having a swing angle of 90 °, and a rotating holder. And a stopper 42 that locks 30 so as not to rotate from the reference rotation position. Then, the holder rotation mechanism is controlled by the following procedures (1) to (4), whereby the rotation of the rotation holder 30 from the current reference rotation position by 90 ° in the clockwise direction in plan view is performed. Can be converted to a position.
(1) Release of the rotation holder 30 by the stopper 42 is released.
(2) The rotary actuator 41 is swung 90 ° clockwise in plan view.
(The rotation holder 30 rotates to the next reference rotation position.)
(3) The rotation holder 30 is locked at the next reference rotation position by the stopper 42.
(4) The rotary actuator 41 is swung 90 ° counterclockwise in plan view.
(The rotation holder 30 remains at the next reference rotation position.)

  As described above, the rotation holder 30 can be converted to the next reference rotation position by the above procedures (1) to (4). Therefore, by repeating the procedures (1) to (4), as shown in FIG. In addition, it is possible to selectively hold the rotary holder 30 at any reference rotational position so that the required treading pressure heads 31 to 34 are opposed to the transport passage 8. Note that the holder rotation mechanism may be configured to rotate the rotary holder 30 using a servo motor instead of the rotary actuator 41.

  Further, the polishing apparatus 3 is provided with a rotation position detection mechanism for detecting at which reference rotation position the rotation holder 30 is held. As shown in FIGS. 3 and 4, the rotational position detection mechanism includes a plurality of limit switches 45 disposed behind the rotation holder 30 and a switch pressing unit 46 disposed at the tip of the rotating arm 30 b. Do it. The switch pressing portion 46 is arranged in a different manner for each rotating arm portion 30b. At each reference rotation position of the rotating holder 30, the switch pressing portion 46 of the rotating arm portion 30b extending rearward is the limit switch 45. Are configured to press in different manners. Therefore, according to this rotational position detection mechanism, the control device can identify the reference rotational position at which the rotational holder 30 is held based on the output of the limit switch 45.

  The holder advance / retreat mechanism 49 is a general-purpose ball screw actuator including a ball screw, a linear guide, and a servo motor. The holder advancement / retraction mechanism 49 integrally drives the rotation holder 30, the holder rotation mechanism, and the rotation position detection mechanism forward / backward toward the transport path 8 within a certain movable range, and holds the position at an arbitrary position. It is possible. 3 and 6A show a state in which the rotary holder 30 and the like are held at the end of the movable range by the holder advance / retreat mechanism 49. In this state, the stepping pressure head 31 facing the conveyance path 8 in the polishing unit 11 is retracted rearward from the tips of the two guide rolls 23 and 24 and is polished between the two rolls 23 and 24. The belt 25 is held at the retracted position retracted inside the belt 25. Thus, in the state where the stepping pressure head 31 of the polishing unit 11 is held in the retracted position, the stepping pressure head 31 is separated from the polishing belt 25, so that the rotating holder 30 is moved by the holder rotating mechanism without causing interference with the polishing belt 25. It can be rotated.

  On the other hand, FIG. 6B shows a state in which the holder advancement / retraction mechanism 49 holds the rotary holder 30 and the like closer to the front of the movable range. In this state, the stepping pressure head 31 facing the conveyance path 8 in the polishing unit 11 advances forward from the tips of the two guide rolls 23 and 24 and is polished between the two rolls 23 and 24. This is an extrusion position for pressing the belt 25 forward (on the conveyance path side). In this way, when the rotary holder 30 is advanced forward by the holder advance / retreat mechanism 49 and the treading head 31 of the polishing unit 11 is converted to the push-out position, the polishing belt 25 of the polishing unit 11 is pushed out to the transfer passage 7 and transferred. The side surface of the workpiece W passing through the passage 7 can be polished by the polishing belt 25.

Below, the structure of the treading pressure heads 31 to 34 attached to the rotary holder 30 will be described.
As described above, the rotary holder 30 is mounted with the two pad type pressure heads 31 and 32 and the two roll type pressure heads 33 and 34. As shown in FIG. 8, the pad type tread heads 31, 32 are detachable from the pad holding metal 51 fixed on the rotating arm 30 b of the rotary holder 30 with a screw 55 and the tip of the pad holding metal 51. An elastic pad 50 that is attached and presses the polishing belt 25 from the inside is provided. The pad type tread heads 31 and 32 are fixed to the rotary holder 30 so that the elastic pad 50 faces forward (in the direction of the conveyance path) when held by the polishing unit 11. As shown in FIGS. 5A and 5D, in a state where the pad type tread heads 31 and 32 of the polishing unit 11 are held at the retracted position, the elastic pad 50 is placed inside the polishing belt 25 in the polishing unit 11. After being separated, the polishing belt 25 of the polishing unit 11 is held at a position where it cannot be pressed against the workpiece W passing through the conveyance path 8. On the other hand, as shown in FIGS. 7A and 7D, when the pad-type tread heads 31 and 32 in the polishing unit 11 are converted to the extrusion positions, the elastic pad 50 causes the polishing belt 25 to move from the inner side in the polishing unit 11. The polishing belt 25 can be pressed against the workpiece W that is pressed toward the conveyance path 8 and passes through the conveyance path 8. Note that the elastic pad 50 is in sliding contact with the inner peripheral surface of the rotating polishing belt 25 at the pushing position of the pad type pressure heads 31 and 32, so that the elastic pad 50 is prevented from being worn as shown in FIG. Therefore, the tip of the elastic pad 50 is covered with a wear-resistant sheet 52 made of graphite canvas.

  The elastic pad 50 has a two-layer structure in which a plate-like hard elastic body 50a made of rubber and a plate-like soft elastic body 50b made of sponge are uniformly stacked. Here, as shown in FIG. 8, of the two pad type pressure heads 31 and 32, the first pad type pressure head 31 has a hard elastic body 50a on the distal end side and a soft elastic body 50b on the proximal end side. Arranged, the hard elastic body 50a constitutes a pressing layer that presses the polishing belt 25 against the workpiece W, and the soft elastic body 50b constitutes a support layer that deforms on the back side of the pressing layer according to the uneven shape of the surface of the workpiece W. is doing. The elastic pad 50 of the first pad type treading head 31 is suitable for polishing the flat surface of the workpiece W because the pressing layer is made of the hard elastic body 50a, so that the end sagging hardly occurs. Further, in this embodiment, since the tread head 31 is advanced toward the workpiece W by the ball screw actuator, if the elastic pad 50 is configured by only the hard elastic body 50a, the elastic surface is elastically formed on minute irregularities on the surface of the workpiece W. Although it becomes difficult to adjust the pad 50, the elastic pad 50 is provided with a support layer made of the soft elastic body 50b on the base end side of the hard elastic body 50a, so that the support layer exhibits cushioning properties. Thus, the hard pressing layer can be made to conform to the surface of the workpiece W and polished appropriately.

  On the other hand, as shown in FIG. 8, of the two pad type pressure heads 31 and 32, the second pad type pressure head 32 has a soft elastic body 50 b disposed on the distal end side and a hard elastic body 50 a disposed on the proximal end side. Thus, the soft elastic body 50b forms a pressing layer that presses the polishing belt 25 against the workpiece W, and the hard elastic body 50a constitutes a support layer that supports the pressing layer on the back side of the pressing layer. The elastic pad 50 of the second pad type treading pressure head 32 is suitable for polishing a relatively undulating surface of the workpiece W because the pressing layer is made of the soft elastic body 50b.

  Thus, since the two pad type treading heads 31 and 32 are provided with the elastic pad 50 having different characteristics, the two can be used properly according to the shape and characteristics of the workpiece W to be polished. Here, since these two pad type treading heads 31 and 32 only have the layer structure of the two elastic bodies 50a and 50b constituting the elastic pad 50 reversed, the component parts can be completely shared. There are advantages. Each of the pad-type treading heads 31 and 32 has a mode in which the elastic pad 50 is detached from the pad holding metal 51 and the hard elastic body 50a is disposed on the distal end side, and the soft elastic body 50b is disposed on the distal end side. It can be remounted in two types of modes. That is, the pad type pressure heads 31 and 32 can be used as the first pad type pressure head 31 or the second pad pressure head 32 depending on the direction in which the elastic pad 50 is mounted. As described above, the pad type pressure heads 31 and 32 of this embodiment have an advantage that the single pressure heads 31 and 32 can be used in two types depending on the direction in which the elastic pad 50 is mounted.

  As shown in FIG. 9, the two roll-type treading heads 33 and 34 attached to the rotary holder 30 are formed by externally fitting cylindrical elastic rolls 58 and 59 around the outer periphery of a hard wheel 57. A support shaft 56 that is rotatably supported by a ball bearing 54 is erected on the mounting portion of the rotary holder 30 where the roll type pressure heads 33 and 34 are mounted, and the roll type pressure heads 33 and 34 are horizontally mounted on the support shaft 56. It is pivotally supported. The two roll type pressure heads 33 and 34 are provided with elastic rolls 58 and 59 having different hardnesses. Specifically, a relatively hard elastic roll 58 made of rubber is disposed on one roll-type treading pressure head 33, and a relatively soft elastic roll 59 made of sponge is placed on the other roll-type treading pressure head 34. Is disposed. The rubber elastic roll 58 that is relatively difficult to deform is cut in advance in accordance with the shape of the polished surface of the workpiece W.

  As described above, in the present embodiment, the four treading pressure heads 31 to 34 are mounted on the rotary holder 30, but all the treading pressure heads 31 to 34 are detachable from the rotary arm 30 b of the rotary holder 30. The belt sander machine 1 can be equipped with other pedaling heads instead of these pedaling heads 31-34. Note that the four rotary arm portions 30b of the rotary holder 30 have the same shape, and it is possible to attach a roll-type treading head to a mounting part of the pad-type treading pressure head.

  As described above, in the polishing apparatus 3 according to the present embodiment, the rotary holder 30 is rotationally driven by the holder rotating mechanism, so that any treading pressure heads 31 to 34 are disposed in the polishing unit 11 and face the conveyance path 8. be able to. Then, if the holder advancement / retraction mechanism 49 advances the rotary holder 30 and the holder rotation mechanism to the conveyance path 8 side to convert the stepping pressure heads 31 to 34 of the polishing unit 11 from the retracted position to the pushing position, the stepping pressure heads 31 to 31 are changed. At 34, the polishing belt 25 can be pressed against the workpiece W for polishing. In the polishing apparatus 3, since the four types of pressure heads 31 to 34 are driven to advance and retract together with the rotary holder 30 by the holder advance / retreat mechanism 49, a set of holder advance / retreat mechanisms (ball screw actuators) 49 are provided for the four types of pressure heads. All that is required is placement. Therefore, the polishing apparatus 3 has an advantage that it can be simplified as compared with a conventional polishing apparatus having a plurality of tread heads. Further, in the polishing apparatus 3 of the present embodiment, other stepping pressure heads 31 to 34 that are not in the polishing unit 11 are also driven forward and backward together with the rotary holder 30, but the other stepping pressure heads 31 to 34 are driven by the polishing unit 11. Since the treading pressure heads 31 to 34 are held rearward, they do not interfere with the polishing belt 25 and the workpiece W. In particular, in the present embodiment, when the polishing belt 25 is pressed against the workpiece W by the stepping pressure heads 31 to 34 of the polishing unit 11, the rotation shaft of the rotary holder 30 and the stepping pressure heads 31 to 34 of the polishing unit 11 are related to each other. Since the treading pressure heads 31 to 34 are arranged on a straight line for advancing the workpiece W, there is an advantage that the driving force for advancing the rotary holder 30 can be efficiently transmitted to the treading pressure heads 31 to 35.

  Further, in this embodiment, since the ball screw actuator constitutes the holder advance / retreat mechanism 49, when the stepping pressure heads 31 to 34 in the polishing unit 11 are converted into the pushing positions, the types of the stepping pressure heads 31 to 34 are changed. Accordingly, the advancement amount of the rotary holder 30 can be adjusted. For this reason, in this polishing apparatus 3, the polishing belt 25 is pushed against the workpiece W with a force suitable for the hardness and shape of each of the stepping pressure heads 31 to 34 without providing an advance / retreat mechanism for each of the stepping pressure heads 31 to 34. It is possible to hit.

Below, control of the belt sander machine 1 by a control apparatus is demonstrated.
The control device is composed of a programmable logic controller and polishes the side edge of the workpiece W by sequence control. Specifically, when polishing the workpiece W, the control device rotationally drives the roller conveyor 6 of the transfer device 2 to transfer the workpiece W from the right to the left of the transfer path 8 and the polishing device 3. The polishing belt 25 is rotated, and the polishing belt 25 is pressed against the side edge of the workpiece W at the timing when the workpiece W passes (see FIG. 1). More specifically, a work detection sensor (not shown) for detecting the work W is disposed in the transport passage 8 at a position in front of the polishing apparatus 3, and the control device is based on a detection signal of the work detection sensor. At an appropriate timing, the holder advance / retreat mechanism 49 advances the rotary holder 30 toward the conveyance path 8 to convert the tread heads 31 to 34 facing the conveyance path 8 from the retracted position to the push-out position. Further, the control device retracts the rotary holder 30 from the conveyance path 8 by the holder advance / retreat mechanism 49 at an appropriate timing based on the detection signal stop of the workpiece detection sensor, and the stepping pressure heads 31 to 34 facing the conveyance path 8. Is converted from the pushing position to the retracted position.

  Here, in the control device, an advance amount by which the rotary holder 30 is advanced toward the conveyance path 8 can be set for each of the stepping pressure heads 31 to 34 via the operation panel 4. When the stepping pressure heads 31 to 34 facing the conveyance path 8 are converted from the retracted position to the pushing position, the control device moves the rotary holder 30 according to the type of the stepping pressure heads 31 to 34 of the polishing unit 11. Only the holder advancing / retreating mechanism 49 is controlled to advance toward the transport path 8. Thus, in this embodiment, the advancement amount of the rotary holder 30 is set in advance for each of the stepping pressure heads 31 to 34, so that the advancement amount of the rotary holder 30 is set every time the stepping pressure heads 31 to 34 are switched. Work becomes unnecessary.

  In addition, the control device appropriately controls the polishing device 3 so that required treading heads 31 to 34 face the conveyance path 8. Specifically, when the type of the pressure heads 31 to 34 used for polishing is specified via the operation panel 4, the control device controls the holder rotating mechanism to rotate the rotating holder 30 by 90 degrees. Thus, the rotary holder 30 is held at the reference rotation position where the required treading heads 31 to 34 are located in the polishing unit 11.

  As mentioned above, although the Example of this invention was described, the belt sander machine of this invention can add a various change within the range which is not restricted to the form of the said Example and does not deviate from the summary of this invention.

  For example, although the said Example is a belt sander machine which grind | polishes wood, this invention is applicable similarly to the belt sander machine which grind | polishes other than wood. In the above embodiment, only one polishing apparatus 3 is provided. However, a plurality of polishing apparatuses may be arranged along the transport path. Moreover, although the said grinding | polishing apparatus 3 grind | polishes the side edge of the workpiece | work W, you may grind | polishes other than the side edge of the workpiece | work W. FIG. Moreover, although the said grinding | polishing apparatus 3 is the structure which presses the grinding | polishing part 11 to the workpiece | work W from a horizontal direction, the structure which presses the grinding | polishing part 11 to the workpiece | work W from the up-down direction or the diagonal direction may be sufficient as this invention. .

  Further, although the rotary holder 30 according to the above embodiment has a cross shape in plan view, the rotary holder according to the present invention may have a disk shape in plan view or a Y shape in plan view. The rotary holder 30 is a plate-like member configured to mount the stepping pressure heads 31 to 34 on the upper side, but the rotation holder according to the present invention holds the stepping pressure heads 31 to 34 from both sides (up and down). It may be a thing.

  Moreover, although the four types of pressure heads 31 to 34 are attached to the rotary holder 30 of the above embodiment, the number and types of the pressure heads attached to the rotary holder according to the present invention can be changed as appropriate.

  In the polishing apparatus 3 of the above embodiment, the polishing belt 25 is wound around the three rolls 22 to 24. However, the polishing belt may be wound around four or more rolls. Moreover, in the said Example, although the roll 22 of the back side is made into a drive roll, you may make it use rolls other than a back side as a drive roll.

DESCRIPTION OF SYMBOLS 1 Belt sander machine 2 Conveyance apparatus 3 Polishing apparatus 6 Roller conveyor 7 Guide rail 8 Conveyance path 11 Polishing part 20 Housing | casing 22 Drive roll 23, 24 Guide roll 25 Polishing belt 30 Rotary holder 31, 32 Pad type pressure head 33, 34 roll Die treading head 49 Holder advance / retreat mechanism 50 Elastic pad 50a Hard elastic body 50b Soft elastic body 51 Pad holding bracket 52 Wear-resistant sheet W Workpiece

Claims (5)

A belt sander machine provided with a polishing device that is disposed in the vicinity of a conveyance path through which a workpiece is conveyed and that presses an endless polishing belt wound around a plurality of rolls against the workpiece by a stepping pressure head to polish the workpiece,
The polishing apparatus comprises:
A plurality of tread heads are mounted around the center of rotation, and are supported on the inner side of the polishing belt so that the plurality of rolls and the rotation shaft are substantially parallel, and can advance and retreat toward the transport path. A held rotating holder;
A holder rotating mechanism capable of driving the rotary holder and holding the rotary holder at a rotational position where each of the treading pressure heads faces the conveyance path;
By driving the rotary holder and the holder rotating mechanism back and forth toward the transport path, the retracting position for retracting the treading head facing the transport path to the inside of the polishing belt, and transporting the polishing belt to the transport path. A belt sander machine comprising a holder advance / retreat mechanism that can be converted into an extrusion position that presses toward a passage.   The belt sander machine according to claim 1, wherein the holder advance / retreat mechanism is a ball screw actuator. The holder advancing / retreating mechanism is configured to control the rotational position of the rotating holder via the holder rotating mechanism so that the required treading pressure head faces the conveying path, and to advance the rotating holder toward the conveying path. A control device for controlling and converting the treading head from the retracted position to the pushing position;
The control device can set the advance amount to advance the rotary holder toward the conveyance path for each of the treading pressure heads, and when converting the treading pressure head from the retracted position to the pushing position, 3. The belt sander according to claim 2, wherein a holder advancing / retreating mechanism is controlled to advance the rotary holder toward the conveyance path by an advance amount corresponding to the stepping pressure head. At least one of the plurality of treading pressure heads includes a pad holding fitting attached to the rotating holder, an elastic pad attached to a tip portion of the pad holding fitting, and an abrasion-resistant sheet covering the tip portion of the elastic pad. A pad-type treading head that presses the polishing belt from the inner side to the conveying path side with the elastic pad covered with the wear-resistant sheet,
The elastic pad of at least one of the pad type treading heads has a layer structure, and a support layer made of a soft elastic material is provided on the base end side of the elastic pad, The belt sander machine according to claim 2 or 3, wherein a pressing layer made of an elastic material harder than the support layer is provided. At least one of the plurality of treading pressure heads includes a pad holding fitting that is attached to the rotating holder, an elastic pad that is detachably attached to a tip portion of the pad holding fitting, and an abrasion resistance that covers the tip portion of the elastic pad. A pad-type treading head that presses the polishing belt from the inside to the conveyance path side with the elastic pad covered with the wear-resistant sheet.
The elastic pad of at least one of the pad type treading heads has a two-layer structure including a first layer made of a soft elastic material and a second layer made of an elastic material harder than the first layer. A mode in which the first layer is disposed and attached to the tip side of the elastic pad with respect to the pad holding metal, and the second layer is provided on the tip side of the elastic pad with respect to the pad holding metal The belt sander machine according to any one of claims 1 to 4, wherein the belt sander machine can be mounted in at least two types of modes, i.e., arranged and mounted.

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