JP5103288B2 - Method and apparatus for welding thermoplastic band - Google Patents

Description

  The present invention employs a packing machine for packing a material to be bound by welding both ends of a thermoplastic band that circulates around the object to be bound, and reciprocates in the width direction at the overlapping portion of the band that wraps around the object to be bound It is related with the welding method and welding apparatus of the thermoplastic band which melt | dissolve the overlapping surface of a band with friction heat, and welds the both ends of a band by this fusion.

  For packing work to wind the object to be bound with a thermoplastic band, after tightening the thermoplastic band that wraps around the object to be bound, cut the middle of the upper band and overlap both ends of the band. A packaging machine in which both ends are welded by melting is used, and a manual packaging machine in which the band is tightened by swinging the handle is one of them.

  Also, as a method of welding both ends of the thermoplastic band in the packing machine, a method of heating and melting with a heater sandwiching the opposed surfaces of the upper and lower bands and pressurizing and welding after removing the heater has been adopted. However, recently, a method has been proposed in which one of the pressurized upper and lower bands is reciprocated at a high speed in the width direction, and the overlapping surfaces of the bands are melted by frictional heat and welded.

  In a conventional packing machine, the both ends of the thermoplastic band are welded by frictional heat, and the upper end of the swing block is attached to the piston of the pressure cylinder, and the fulcrum for the swing block to swing in the width direction of the band. The upper band presser provided at the lower end of the swing block and the fixed lower band receiver disposed directly below the pin are sandwiched between the upper and lower portions of the thermoplastic band, and the middle of the swing block By rotating the eccentric shaft that penetrates the upper band, the upper band is reciprocated in the width direction with the upper band holder, and at the same time, pressure is applied to the piston of the pressure cylinder with pressurized air to depress the upper band holder, The overlapping surface is melted by friction and welded (for example, see Patent Document 1).

As another welding method, a lower upper band presser is provided via a spring on the upper surface of the press block that reciprocates in the band width direction by rotation of the eccentric shaft, and a fixed upper band receiver is disposed immediately above the thermoplastic resin. The upper and lower bands overlap by sandwiching the upper and lower parts of the band, rotating the eccentric shaft, reciprocating the lower band in the width direction with the lower band presser, and pushing up the lower band presser with the elasticity of the spring. The surface is melted by friction and welded (for example, see Patent Document 2).
Japanese Patent No. 3306659 JP-A-5-46702

  By the way, the former welding method in which the overlapping portion of the upper and lower bands is pressure-bonded with the pressing force of the pressurized air requires a separate equipment for generating pressurized air, and the welding apparatus becomes expensive and the pressure-adjusting pressure is adjusted. There is a problem that it is difficult to do.

  Also, during the band cutting process, the blade that moves up and down integrally with the rocking block cuts the upper band with the fixed base when lowered by pressing down with pressurized air. When the elastic blade is pushed down, it takes time until the cutting pressure required for the blade is applied, and there is a problem that the welding conditions are not stable, such as defective cutting or fluctuation in time until completion of cutting.

  In addition, the latter welding method using the pressure of the spring not only takes time to melt the band, but also as the melting of the upper and lower bands becomes deeper, as the melting of the upper and lower bands becomes deeper, the pressing force becomes weaker. There is a problem that a long cooling time is required.

  Therefore, the object of the present invention is not only to simplify the structure in order to solve the above-mentioned problems, but also to increase the pressing force of the upper and lower bands and at the same time follow the change in the melting degree of the bands. An object of the present invention is to provide a thermoplastic band welding method and welding apparatus that can reliably perform band welding without taking time by maintaining a strong pressing force.

  In order to solve the above-mentioned problems, the invention of claim 1 is characterized by sandwiching the upper and lower portions of the thermoplastic band between the upper band holder and the lower band holder, and reciprocating in the width direction while holding the upper band with the upper band holder. This is a method of welding a thermoplastic band that melts and welds the overlapping surfaces of the upper and lower bands by friction. The upper band presser is moved up and down by the rotation of the eccentric cam, and the eccentric cam descends near the bottom dead center. The upper band presser presses the band at the position, and the upper band presser at the lowered position reciprocates in the width direction of the band to melt the overlapping surface of the upper and lower bands by friction. A configuration is adopted in which the upper band presser is lowered following the melting degree of the band by the rotational elasticity biased toward the dead point.

In the invention of claim 2, the upper and lower bands are overlapped by sandwiching the upper and lower portions of the thermoplastic band between the upper band holder and the lower band holder, and reciprocating the upper band in the width direction with the upper band holder. This is a thermoplastic band welding device that is melted and welded by friction. A rocking block is arranged directly above the lower band holder so as to be movable up and down, and this rocking block is rocked by the rotation of an eccentric cam provided on the operation shaft. A vertical motion imparting mechanism that applies vertical motion to the motion block, and a position of the band on the rocking block by the rotation of the eccentric cam by the rotary drive unit while allowing the rocking block to move vertically while being positioned below the vertical motion imparting mechanism. A part that is supported by a rocking imparting mechanism that gives rocking in the width direction, faces the lower band receiver at the lower part of the rocking block, and overlaps the band by lowering the rocking block An upper band presser that clamps the upper band presser with a lower band receiver is provided, and the vertical movement imparting mechanism is set so that the eccentric band is pressed by the upper band presser when the phase of the eccentric cam is close to the bottom dead center. A configuration is adopted in which the rotational elasticity toward the bottom dead center is biased so that the swing block descends following the degree of melting.

  According to a third aspect of the present invention, the rocking block is housed in a case fixed on the base of the packaging machine, and the eccentric cam housing hole of the vertical movement imparting mechanism is formed in a horizontally long hole, and rocks at the upper part of the rocking block. Both side edges in the direction are arc-shaped edges, and the arc-shaped edges of this swing block are sandwiched from both sides by the inner surface of the case body and an adjuster provided in the case body so that the vertical position can be adjusted. The held configuration is adopted.

  According to a fourth aspect of the present invention, the vertical motion imparting mechanism includes an eccentric cam that vertically moves the swing block by rotation of the operation shaft, a switch cam provided on the operation shaft, and a swing block that is rotated by the operation shaft. A switch that is pushed by the switch cam in the lowered position to operate the rotation driving machine of the swing imparting mechanism and the eccentric cam via the operation shaft, and the axis and axis of the operation shaft by rotation of the operation shaft A configuration is adopted in which a spring formed by switching and imparting a rotational elasticity toward the top dead center and a rotational elasticity toward the bottom dead center by passing through the dead center where the crossing points.

According to a fifth aspect of the present invention, there is provided a cutter which is fixedly disposed at a lower edge of the swing block at a side edge positioned on a pulling side of the upper band so as to be positioned below the upper band when the swing block is lowered. The structure provided with the band cutting blade which cut | disconnects a band is employ | adopted.
The invention of claim 6 employs a configuration in which the upper band presser is attached to the lower part of the swing block so as to be swingable in the band width direction via a fulcrum pin.

  Here, the case body comprises a combination of a case body having a U-shaped cross section fixed in an upright state on a rectangular base, and a cover for closing the upper surface and the side surface of the case body. A horizontal operating shaft is rotatably supported by the upper part of the opposing wall, and a horizontal driving shaft is also rotatably supported by the lower part. A swing block is housed inside the case body, and the upper surface of the base swings. A lower band receiver is fixed at a position directly below the moving block.

  In this rocking block, a horizontally long hole formed in the upper part is fitted to an eccentric cam provided on the operation shaft, and a vertically long hole formed below the horizontally long hole is fitted to an eccentric cam provided on the drive shaft. When the drive shaft is rotated by the connected swing motor, the swing block reciprocally swings about the shaft center of the upper arc-shaped edges on both sides by the rotation of the eccentric cam of the drive shaft.

  The upper half of the swing block is an arc edge centered on the axis centered on the vertical center line of the swing block, one arc edge is in sliding contact with the cover, and the other arc edge is the interior of the case body. Slidably in contact with the adjuster attached to the side and pinching the swinging block in a state allowing the swinging of the swinging block from both sides, providing a fulcrum for swinging and eliminating noise during swinging as well as noise countermeasures. By adjusting the position of the swing block, it is possible to prevent the occurrence of rattling due to wear of the arc edge, to stabilize the swing block without reducing the amplitude when swinging, and to meet the heat generation requirements of the overlapping part of the upper and lower bands. ing.

  The lower end of the swing block is a box whose bottom surface is open, and an upper band presser with an upper shaft body inserted into the box is attached to the box with a fulcrum pin that penetrates the shaft body, The upper band presser can be reciprocated in a state that is always parallel to the band surface.

  On the lower surface of the box of the swing block, a lower edge located on the drawer side of the upper band is formed on the cutting blade, and when the swing block is lowered, the upper band is cut with a cutter fixed to the case body. .

  The operation shaft has a rotary knob fixed at one end, a switch cam is fixed at the other end of the operation shaft, and a switch is fixed at a position slightly away from the outer periphery of the switch cam. The other end of the spring, which is disposed and has one end connected to the outer periphery of the switch cam, is fixed to the case body, and passes through a dead point where the axis of the spring intersects the axis of the operating shaft to the left or right As a result, either the rotational elasticity toward the top dead center or the rotational elasticity toward the bottom dead center is switched and applied to the eccentric cam via the operation shaft.

  Therefore, the swing block is in the raised position with the eccentric cam of the operating shaft at the top dead center, and when the operating shaft is rotated, the end of the spring connected to the switch cam rotates, so that When the shaft passes through the axis of the operating shaft, the eccentric cam is given rotational elasticity toward the bottom dead center.

  According to the first and second aspects of the present invention, when the upper band presser presses the band at the lowered position near the bottom dead center of the eccentric cam, and the overlapping surface of the upper and lower bands is melted by frictional heat, The upper band presser is made to follow the melting degree of the band by rotating elasticity biased toward the bottom dead center, so it is strong by the band press near the bottom dead center of the eccentric cam. The band can be pressed with force, and the band can be melted by friction efficiently in a short time, and the band pressing force does not weaken against the change in the melting degree of the band, but rather becomes stronger. The cooling time of the welded portion is shortened, and the efficiency of bundling work by the band can be improved.

  According to the invention of claim 3, both side edges in the swing direction are formed as arc-shaped edges at the upper part of the swing block, and the arc-shaped edges of the swing block are provided in the inner surface of the case body and the case body so that the vertical position can be adjusted. Since it is held as a fulcrum when swinging by sandwiching it from both sides with an adjuster, generation of vibration noise due to rattling can be achieved by holding the part that becomes the fulcrum when swinging the swing block so that there is no backlash. The band can be welded in a quiet state, and by adjusting the position of the adjuster, it is possible to prevent the occurrence of rattling due to wear of the arc edge, thereby eliminating the decrease in amplitude when the rocking block swings. And can meet the heat generation requirements of the overlapping parts of the upper and lower bands.

  According to the invention of claim 4, by rotating the operating shaft, the eccentric cam is rotated toward the top dead center by passing through the dead center where the axis of the operating shaft and the axis of the spring intersect. Since the rotation elasticity toward the bottom dead center is switched and given, the band can be welded and released quickly by rotating the operation shaft, and at the same time, the eccentric cam is directed toward the bottom dead center. By imparting rotational elasticity, the band can be pressed with a strong force, and the band can be melted and welded by friction in a short time.

  According to the invention of claim 5, a band cutting blade is provided at the lower edge of the swing block on the side edge located on the drawer side of the upper band, and when the swing block is lowered, it is fixedly disposed so as to be positioned below the upper band. Since the upper band is cut with the cutter, the band cutting blade that descends with the rotational force of the eccentric cam can cut the band mechanically with the cutter, preventing the occurrence of cutting failure of the band and completing the cutting. The time until the time is constant, and the welding conditions can be stabilized.

  According to the invention of claim 6, since the upper band presser is attached to the lower part of the swing block so as to be swingable in the width direction of the band via the fulcrum pin, The upper band presser always reciprocates in parallel with the band surface, so that the upper and lower bands can be reliably welded.

  Hereinafter, embodiments of the present invention will be described based on illustrated examples.

  As shown in FIG. 1, a manual packing machine 1 that packs the object to be bound b using a thermoplastic synthetic resin band a has an upper surface of a rectangular base 2 placed on the object to be bound b. A lower band receiver 3 is provided so as to be fitted into a recess formed in the base 2, and the base 2 is arranged along the length direction of the band a with respect to the band a that circulates around the bundled object b. It becomes.

  Along with the length direction of the case body 4 that houses the main mechanism of the band welding device and the band a that circulates around the object to be bound b, it is arranged on the upper part of the base 2 and directly above the lower band receiver 3. Positioned on the left side when viewed from the front in FIG. 1 with the case body 4 in between, the middle of the upper band a1 is firmly held so as not to move in the loosening direction with the upper surface of the base 2 and allowed to be pulled out to the case body 4 side. Clamp claw 6 which is located on the right side of the figure and clamp claw 5 is fixed to the upper surface of base 2 so as not to move in the loosening direction and allows insertion toward case body 4 side. And a winding shaft 8 that is positioned on the side of the upper band a1 with respect to the clamp pawl 6 and that rotates in one direction via the ratchet mechanism by swinging the handle 7 to wind up the upper band a1. It has a structure.

  As shown in FIGS. 2 and 3, the case body 4 includes a case body 9 having a U-shaped cross section fixed in an upright state on the base 2 so that an open surface faces forward, and a screw fixing to the case body 9 The case body 9 includes a combination of a cover 10 that closes the upper surface and the front surface, and the case body 9 supports a horizontal operation shaft 12 rotatably on the opposite side walls 11, 11 via bearings 13, 13. A horizontal drive shaft 14 is rotatably supported via bearings 15 and 15 at a position directly below the operation shaft 12 in the lower part.

  The operation shaft 12 is provided with an eccentric cam A in the middle between the opposing walls 11, 11. The eccentric cam A rotates on the eccentric shaft 12 a and an eccentric shaft 12 a formed in the middle of the operation shaft 12. The operation shaft 12 is formed with a bearing 16 that is externally fitted so that the knob 17 for rotation operation is fixed to one end protruding to the outside of the case body 4 and the switch cam is connected to the other end. 18 is fixed.

  Further, the drive shaft 14 is provided with an eccentric cam B in the middle between the opposing walls 11, 11. The eccentric cam B includes an eccentric shaft 14 a formed in the middle of the drive shaft 14 and the eccentric shaft 14 a. The drive shaft 14 is connected to a swing motor 20, which is a rotary drive device, at one end protruding to the outside of the case body 4.

  A swing block 21 is accommodated inside the case body 4 so as to be able to move up and down and swing back and forth in the width direction of the band a. Is supported by a vertical motion imparting mechanism 22 that vertically moves the swing block 21 by the rotation of the eccentric cam A provided at a lower position, and the position near the lower portion is located below the vertical motion imparting mechanism 22 and is rocked. The swing block 21 is supported by a swing imparting mechanism 23 that swings the band a in the width direction by the rotation of the eccentric cam B by the swing motor 20 while allowing the motion block 21 to move up and down.

  The swing block 21 includes a block main body 21a having a plate shape that is long in the vertical direction, and a rectangular box 21b having a lower surface provided at a lower end thereof, the box 21b having a lateral width opposite to the opposing wall 11 of the case main body 9, 11, the vertical movement imparting mechanism 22 includes an eccentric cam A provided on the operation shaft 12, and an eccentric cam provided on the upper portion of the block main body 21a so as to be externally fitted to the eccentric cam A. The swing block 21 is vertically moved by rotating the eccentric cam A together with the operation shaft 12 formed by the storage hole 24.

  The swing imparting mechanism 23 is formed by an eccentric cam B provided on the drive shaft 14 and an eccentric cam housing hole 25 provided on the lower portion of the block main body 21a so as to be fitted to the eccentric cam B. The swing block 21 is swung by the rotation of the shaft 14.

  In the vertical motion imparting mechanism 22, the eccentric cam housing hole 24 provided in the block main body 21 a has the same vertical dimension as the diameter of the bearing 16 in the eccentric cam A, but the lateral length is longer than the diameter. When the eccentric cam A is formed in the horizontally long hole and the eccentric cam A rotates in the eccentric cam housing hole 24, it is possible to apply the vertical movement to the swing block 21 without giving the movement of the band a in the width direction (front and back). ing.

  The eccentric cam housing hole 25 in the swing imparting mechanism 23 is formed as a vertically elongated hole, and swings in the width direction of the band a while allowing the swing block 21 to move up and down by the vertical motion imparting mechanism 22. It comes to give movement.

  As shown in FIG. 4B, the front and rear side edges along the width direction of the band a in the upper half of the block main body 21a are the vertical center line in the width direction of the swing block 21 and the length of the eccentric cam storage hole 24. Arc edges 21c and 21c are formed around the intersection with the horizontal center line along the vertical direction, and the arc edges 21c and 21c of the block main body 21a are connected to the front plate of the cover 10 and the rear position in the case main body 9, respectively. A wedge-shaped adjuster 27 that is attached to a screw 26 so that the vertical position can be adjusted, and thereby holds the upper portion of the block main body 21a so as to be movable up and down, and sandwich the rocking block 21 from both sides, thereby forming an arc edge 21c. , 21c serves as a fulcrum when swinging. Thus, by sandwiching the swing block 21 from both sides, it is possible to eliminate noise during swinging and to prevent noise, and to adjust the position of the adjuster 27. To reduce the amplitude when the swing block 21 swings and stabilize it, so that heat generated at the overlapping portion of the upper and lower bands a1 and a2 is reliably obtained. I am trying to do it.

  When the operating shaft 12 is rotated by the knob 17, the swing block 21 moves up and down in the stroke range between the top dead center and the bottom dead center of the eccentric cam A by the eccentric cam A and the eccentric cam housing hole 24. When the drive shaft 14 is rotated at a high speed by the swing motor 20, the eccentric cam B and the eccentric cam housing hole 25 give a back-and-forth reciprocal swing about the axis of the arc edges 21 c and 21 c as a fulcrum.

  The lower surface of the box 21b provided below the swing block 21 faces the lower band receiver 3 directly below, and the overlapped portion of the band a is clamped by the lower band receiver 3 as the swing block 21 descends. A square plate-like upper band retainer 28 is provided, and the upper band retainer 28 has a shaft body 29 provided on the upper surface inserted into the box 21b so that the box 21b and the shaft body 29 are along the length direction of the band a. It is attached to the box 21b with a fulcrum pin 30 that penetrates, and the oscillating block 21 can be oscillated in the front-rear oscillating direction of the oscillating block 21, that is, in the width direction of the band a. It is designed to reciprocate in a state that is always parallel to the surface.

  The vertical movement imparting mechanism 22 of the rocking block 21 moves the rocking block 21 up and down by switching the rotational direction of the eccentric cam A provided on the operation shaft 12. As shown in FIG. 5B, the upper band press 28 is set to press the band a before the phase of the eccentric cam A reaches near the bottom dead center.

  As shown in FIGS. 4 and 5, a switch 31 electrically connected to the swing motor 20 is fixed to the case body 4 at a slightly lower position on the outer periphery of the switch cam 18 fixed to the operation shaft 12. The protrusion 18a of the switch cam 18 turns on the switch 31 when the operating band 12 is rotated and the upper band press 28 presses the overlapping portion of the upper and lower bands a1 and a2 against the lower band receiver 3. Then, the swing motor 20 is activated to rotate the drive shaft 14 and swing the swing block 21 back and forth.

  As shown in FIGS. 4A and 5A, the switch cam 18 is positioned on the outer periphery of the switch cam 18 at a position separated from the protrusion 18a by a little less than a half circumference in the circumferential direction, and on the outer surface of the case body 4. Also, pins 32 and 33 that are parallel to the operation shaft 12 project from the left side with respect to the vertical axis of the operation shaft 12 below, and a spring 34 is stretched between the pins 32 and 33 so that the switch A rotational force in a direction in which the eccentric cam A is directed to the top dead center and a rotational force in a direction in which the eccentric cam A is directed to the bottom dead center can be switched and applied to the operation shaft 12 via the cam 18.

  FIGS. 4A and 4B show a state where the eccentric cam A of the operation shaft 12 is at the top dead center. The swing block 21 is held at the raised position, and between the upper band presser 28 and the lower band receiver 3. The switch cam 18 has a protrusion 18 a away from the switch 31 and the spring 34 is offset to the left with respect to the vertical axis of the operation shaft 12. .

  When the operation shaft 12 is rotated in the clockwise direction in FIG. 4A, the spring 34 is tilted to the right side while the locking point to the pin 32 is rotated and extended, and the axis of the spring 34 is rotated. When passing through the dead center intersecting the axis of the operation shaft 12 to the descending side, which is the right side of FIG. 5A, the elasticity of the spring 34 causes the operation shaft 12 to rotate in the direction in which the eccentric cam A moves toward the bottom dead center. Energize.

  As described above, when the operating shaft 12 is rotated in the clockwise direction in FIG. 4A, the eccentric cam A at the top dead center is rotated toward the bottom dead center, so that the swing block 21 is lowered. When the axis of the spring 34 passes through the dead point where the axis of the operating shaft 12 intersects the lowering side, the swing block 21 rapidly moves down, and the upper band press 28 before the eccentric cam A reaches the lower dead point. Presses the overlapping portion of the upper and lower bands a1 and a2 onto the lower band receiver 3, and at this point, the switch cam 18 is turned on when the projection 18a pushes the switch 31 as shown in FIG. The motor 20 starts and the drive shaft 14 rotates, and the swing block 21 swings in the width direction of the band a, and the melting of the band a starts.

  As shown in FIG. 5B, the lowering of the swing block 21 causes the upper band presser 28 to press the band a at a phase before the eccentric cam A reaches the bottom dead center. The elasticity acts as a push-down force of the swing block 21 and melts the overlapping portion of the upper and lower bands a1 and a2 by pressing them with a strong force, and the swing motor 20 stops at a preset time and the melting process is completed. By continuing pressing, the melted portion is welded.

  A band cutting blade 35 is provided at the lower edge of the box 21b in the swing block 21 at the side edge located on the drawer side of the upper band a1, and the cutter 36 is fixed to the position on the drawer side of the upper band a1 below the case body 9. The upper band a1 is cut by the band cutting blade 35 and the cutter 36 when the swing block 21 is lowered.

  The manual packing machine provided with the band welding apparatus of the present invention has the above-described configuration, and next, a packing method using a thermoplastic band will be described.

  As shown in FIG. 1, the packing machine 1 is placed on the object to be bundled b, and the tip of the band a that circulates around the object to be bundled b in the state where the swing block 21 is held at the raised position, And inserted between the clamp 36 on the right side of the figure and from the bottom of the cutter 36 to the middle of the left end of the lower band receiver 3 and the left clamp claw 5.

  The pull-out side of the band a is between the left clamp claw 5 and the base 2 in FIG. 1, between the upper band press 28 and the lower band receiver 3, between the lower end of the case body 4 and the cutter 36, and on the right clamp claw 6 in FIG. The guide groove 6a is sequentially inserted and inserted into the groove 8a of the winding shaft 8.

  In this state, the winding shaft 8 is rotated by the handle 7, the band a is wound around the winding shaft 8, and the object to be bound b is tightened with an appropriate tension.

  At this time, the spring 34 connected to the switch cam 18 of the operating shaft 12 is on the left side with respect to the vertical axis of the operating shaft 12 as shown in FIG. 4A, and the phase of the eccentric cam A of the operating shaft 12 is 4 (b), the swing block 21 is held at the raised position as shown in FIG. 2, and the upper band presser 28 is spaced from the lower band receiver 3.

  In this state, when the knob 17 is gripped and the operating shaft 12 is rotated in the clockwise direction of the arrow in FIG. 4A against the elasticity of the spring 34, the eccentric cam A of the operating shaft 12 rotates toward the bottom dead center. When the eccentric cam A is pushed down, the swing block 21 moves downward, and the band cutting blade 35 provided in the box 21b mechanically cuts the upper band a1 with the cutter 36.

  When the upper band a1 is cut, since the axis of the extended spring 34 passes through the dead point where the axis of the operating shaft 12 intersects the lower side, the tension of the spring 34 rotates the eccentric cam A to the lower dead point. As shown in FIGS. 5 (a) and 5 (b), the upper band presser 28 presses the overlapping portion of the upper and lower bands a1 and a2 onto the lower band receiver 3 as shown in FIGS. At this point, the switch cam 18 has the projection 18a pushing the switch 31.

  When the switch 31 is turned on, the oscillating motor 20 is energized, and the eccentric cam B of the drive shaft 14 fitted in the eccentric cam housing hole 25 that becomes the vertically long hole of the oscillating block 21 rotates in the state shown in FIG. Then, the swing block 21 swings back and forth at high speed in the width direction of the band a with the centers of the arc edges 21c and 21c as fulcrums, and the upper band press 28 provided at the lower end stops the upper band a1 and the lower band a2 On the other hand, the band a is reciprocated in the width direction in a pressurized state, and the band a is pressed with a strong force by the band pressing near the bottom dead center of the eccentric cam A due to the elasticity of the spring 34, and the upper and lower bands a1 and a2 are The overlapping surface is efficiently melted by heat generated by friction.

  At this time, the upper and lower bands a1 and a2 are reduced in thickness by melting of the overlapping surfaces, but the rocking block 21 is attached to the eccentric cam A toward the bottom dead center by the elasticity of the spring 34. Since the band pressing force is applied by the urging rotational elasticity, the upper band presser 28 descends following the degree of melting of the band a, and the overlapping surface of the upper and lower bands a1 and a2 can be efficiently melted.

  The upper band presser 28 is attached to the lower part of the swing block 21 via a fulcrum pin 30 so as to be swingable in the width direction of the band a. The lower surface of the upper band retainer 28 reciprocates in parallel with the band surface at all times, so that the upper and lower bands a1 and a2 can be reliably welded.

  Further, when the swing block 21 swings, the front and rear arc edges 21c and 21c in the swing direction of the block main body 21a are held between the cover 10 and the adjuster 27 of the case body 4, so It is possible to hold the portion serving as a fulcrum of the block main body 21a at the time so that there is no rattling, and it is possible to perform band welding in a quiet state by suppressing the generation of vibration noise caused by rattling, and to adjust the position of the adjuster 27 If the wear generated on the arc edges 21c and 21c is absorbed, the occurrence of wear on the arc edges 21c and 21c due to rattling is suppressed, and the occurrence of a decrease in amplitude when the swing block 21 swings is eliminated. This stabilizes the heat generation of the overlapping portion of the upper and lower bands a1 and a2.

  When the set rotation time of the swing motor 20 according to the type and material of the band a elapses, the swing motor 20 stops and the swing block 21 stops swinging, and the swing block 21 is connected to the upper and lower bands a1 and a2. By continuing the pressing, the melted portion is welded, and the bundling operation is completed. Thereafter, the operation shaft 12 is rotated by the knob 17 in the direction opposite to that during bundling, and FIGS. 4 (a) and 4 (b). As described above, the eccentric cam A is returned to the top dead center, the swing block 21 is held in the raised position, and the base 2 is pulled out between the band a and the object to be bundled b. What is necessary is just to isolate | separate from b.

A partially longitudinal front view of a band-wrapped state showing a manual packing machine equipped with a band welding device of the present invention Longitudinal side view of a band winding state in which the main part of the band welding device in the packing machine is enlarged. Exploded perspective view of band welding equipment (A) is an enlarged vertical side view of the band welding apparatus as seen from the switch cam side before band welding, and (b) is an enlarged view of the band welding apparatus as seen from the side opposite to the switch cam before band welding. Center profile side view (A) is an enlarged longitudinal side view of the band welding state when the band welding device is viewed from the switch cam side, and (b) is an enlarged central longitudinal side view of the band welding state when the band welding device is viewed from the side opposite to the switch cam.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Packing machine 2 Base 3 Lower band receptacle 4 Case body 5 Clamp claw 6 Clamp claw 7 Handle 8 Winding shaft 9 Case body 10 Cover 11 Opposite wall 12 Operation shaft 13 Bearing 14 Drive shaft 15 Bearing 16 Bearing 17 Knob 18 Switch cam 19 Bearing 20 Oscillating motor 21 Oscillating block 22 Vertical motion imparting mechanism 23 Oscillating imparting mechanism 24 Eccentric cam storage hole 25 Eccentric cam storage hole 26 Screw 27 Adjuster 28 Upper band retainer 29 Shaft body 30 Support pin 31 Switch 32 Pin 33 Pin 34 Spring 35 Band cutting blade 36 Cutter A Eccentric cam B Eccentric cam

Claims (6)

By sandwiching the upper and lower parts of the thermoplastic band between the upper band holder and the lower band holder and reciprocating in the width direction while holding the upper band with the upper band holder, the overlapping surfaces of the upper and lower bands are melted by friction. It is a welding method of a thermoplastic band to be welded,
The up and down movement of the upper band presser is given by the rotation of the eccentric cam, and the upper band presser presses the band at the lowered position near the bottom dead center of the eccentric cam, and the upper band presser at the lowered position is moved in the band width direction. The upper and lower band overlap surfaces are melted by friction by reciprocating, and at this time, the upper band presser descends following the melting degree of the band by the rotational elasticity biased toward the bottom dead center with respect to the eccentric cam. A method for welding thermoplastic bands. The upper and lower band holders are sandwiched between the upper and lower band holders, and the upper band is reciprocated in the width direction with the upper band holder to melt and weld the overlapping surfaces of the upper and lower bands by friction. A welding device for thermoplastic bands,
A swing block is arranged directly above the lower band support so as to be movable up and down, and the swing block is moved up and down by an eccentric cam provided on the operation shaft. It is located below the applying mechanism, and is supported by a swing applying mechanism that allows the swing block to swing in the width direction of the swing block by the rotation of the eccentric cam while allowing the swing block to move up and down. An upper band presser is provided at the lower part of the swing block so as to face the lower band receiver and clamp the overlapped portion of the band with the lower band receiver by lowering the swing block. The upper band presser is set so that the upper band presser presses the band when the phase is near the bottom dead center, and this eccentric cam is designed to rotate elastically toward the bottom dead center so that the rocking block descends following the melting degree of the band. With Welding apparatus of the thermoplastic band.   The rocking block is housed in a case fixed on the base of the packing machine, the eccentric cam housing hole of the vertical movement imparting mechanism is formed in a horizontally long hole, and both side edges in the rocking direction are arcuate edges at the top of the rocking block. The arcuate edge of the swing block is held between the inner surface of the case body and an adjuster provided in the case body so that the vertical position of the swing block can be adjusted from both sides, and is held as a fulcrum during swinging. Thermoplastic band welding equipment.   The vertical motion imparting mechanism includes an eccentric cam that vertically moves the swing block by rotation of the operation shaft, a switch cam provided on the operation shaft, and a switch in a state where the swing block is in the lowered position by rotation of the operation shaft. A switch that is pressed by the cam to operate the rotation drive of the swing imparting mechanism and the eccentric cam via the operation shaft passes through the dead center where the axis of the operation shaft intersects with the axis when the operation shaft rotates. The thermoplastic band welding apparatus according to claim 2 or 3, wherein the thermoplastic band welding device is formed by a spring for switching and imparting rotational elasticity toward the top dead center and rotational elasticity toward the bottom dead center.   A band cutting blade that cuts the upper band with a cutter that is fixedly arranged at the lower edge of the swing block at the lower edge of the upper band at the lower edge of the upper band so as to be positioned below the upper band when the swing block is lowered. The thermoplastic band welding apparatus according to any one of claims 2 to 4, further comprising:   The thermoplastic band welding device according to any one of claims 2 to 5, wherein the upper band presser is attached to a lower portion of the swing block so as to be swingable in a band width direction via a fulcrum pin.

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