CN117818962A - Automatic ribbon instrument of compressed air pay-off - Google Patents

Abstract

An automatic strapping tool for compressed air feed comprising: the guide rail and the pull-through cutting combined mechanism; the guide rail is internally provided with an inner cavity capable of accommodating the head part of the ribbon, the guide rail is formed by combining two parts or is a square tubular part formed integrally, and the inner cavity of the guide rail is designed into a straight line or is formed by combining a straight line section and a curve section in the length direction; the threading, pulling and cutting combined mechanism comprises a frame, at least two guide claws and a strap wheel, wherein U-shaped guide grooves for guiding the strap body of the strap are formed in the at least two guide claws, and the bottoms of the U-shaped guide grooves on the at least two guide claws are curved surfaces in the length direction; the frame is provided with a wider U-shaped guide groove for guiding the head of the ribbon and a narrower U-shaped guide groove for guiding the ribbon body of the ribbon; the compressed air can push the front end surface of the head part of the ribbon to the two steps; the elastic potential energy generated by bending the band body of the band can enable the head of the band to automatically fall into the sinking pit on the frame for positioning.

Description

Automatic ribbon instrument of compressed air pay-off

Technical Field

The invention relates to an automatic strapping tool, in particular to an automatic strapping tool capable of feeding by compressed air.

Background

The prior automatic strapping equipment or the prior automatic strapping tool have different technical schemes in the aspects of design of a pull-through cutting functional assembly, a strapping positioning mode and the like, the prior patents of the inventor emphasize that the root or the end face of a second guide claw is used for locking the strapping head, or an elastic locking part capable of swinging is designed to allow the strapping head to pass, after the strapping head passes, the elastic locking part is pushed by the elasticity of a spring to lock the strapping head, and the other prior patents of the inventor adopt the locking part but are not disclosed in the prior patents (also not shown in the drawings), wherein the tolerance requirement on the thickness direction of the strapping head by adopting the method of locking the strapping head by adopting the root of the guide claw is very strict, and if the strapping head is slightly thicker, the strapping head is easy to be blocked (cannot reach an accurate positioning position) so as to cause strapping failure; the scheme of designing the elastic locking part capable of swinging can do swinging avoidance action, although the problem of thickness tolerance of the head of the ribbon is solved by the mode, in the occasion of pushing the ribbon by compressed air, the elastic locking part capable of swinging can greatly block the ribbon moving at high speed, so that the kinetic energy of the ribbon moving is seriously lost, in addition, the kinetic energy loss of the elastic locking part capable of swinging to the ribbon moving is also different due to different ribbon speeds, the kinetic energy loss of the ribbon moving is difficult to calculate and measure, the repeatability and consistency of kinetic energy loss test data are poor, and finally, the ribbon head cannot accurately reach an ideal positioning position; in addition, the design of the pivotable elastic locking element can also lead to a complete failure of the movement function due to the catching of debris in the gap. In order to solve the problems, the self-powered automatic strapping tool for feeding compressed air is designed through years of experiments and summary of structural characteristics of related parts and elasticity of the strapping tape, and is more effective in guiding, improving structural design and combining beneficial results by using relatively simple characteristic structural elements.

Disclosure of Invention

The invention aims to solve the problem that the reliability of the conventional automatic strapping tool for conveying a strapping tape from a host machine to a gun head is insufficient.

The invention is realized by the following technical scheme, an automatic strapping tool for feeding by compressed air comprises: the guide rail and the pull-through cutting combined mechanism; the guide rail is internally provided with an inner cavity capable of accommodating the head part of the ribbon, the guide rail is formed by combining two parts or is a square tubular part formed integrally, and the inner cavity of the guide rail is designed into a straight line or is formed by combining a straight line section and a curve section in the length direction; the cross section of the cavity is larger than that of one ribbon head and the cross section of the cavity can only accommodate the cross section of no more than one ribbon head at most and leave a gap (the cross section of the cavity of the curve section of the guide rail allows the design to be larger); the threading, pulling and cutting combined mechanism comprises a frame, at least two guide claws and a strap wheel, wherein U-shaped guide grooves for guiding the strap body of the strap are formed in the at least two guide claws, the U-shaped guide grooves of the at least two guide claws are the lengths of the U-shaped guide grooves of the at least two guide claws formed by scanning the U-shaped sections along a curve (namely, the bottom surfaces of the U-shaped guide grooves on the at least two guide claws are curved surfaces in the length direction); the machine frame is provided with a wider U-shaped guide groove for guiding the head of the ribbon and a narrower U-shaped guide groove for guiding the ribbon body, the narrower U-shaped guide groove in the machine frame can only allow the ribbon body to pass through but not allow the ribbon head to pass through, the bottom surface of the narrower U-shaped guide groove in the machine frame is set into a curved surface or an inclined plane in the length direction, because the widths of the wider U-shaped guide groove and the narrower U-shaped guide groove in the machine frame are different, the wider U-shaped guide groove in the machine frame is connected with the narrower U-shaped guide groove in the length direction in a head-tail mode to form two steps, the bottom of the wider U-shaped guide groove in the machine frame is provided with a sink, and the sink is arranged at the joint of the wider U-shaped guide groove and the narrower U-shaped guide groove in the machine frame; the narrower U-shaped guide groove on the rack is communicated with the U-shaped guide grooves of the at least two guide claws in a sequential way, and the wider U-shaped guide groove on the rack is communicated with the inner cavity of the guide rail; after the at least two guide claws are closed with the rack, the U-shaped guide grooves of the at least two guide claws are formed into a closed loop or an incompletely closed loop with the wider U-shaped guide grooves and the narrower U-shaped guide grooves on the rack; the inner cavity of the guide rail can be communicated with compressed air, the compressed air can push the front end face of the head of the ribbon to two steps formed by connecting a wider U-shaped guide groove with a narrower U-shaped guide groove on the frame, and the two steps are propped against two sides of the front end face of the head of the ribbon and cannot enable the head of the ribbon to continuously advance; the curved surface or inclined plane of the bottom surface of the narrower U-shaped guide groove on the frame and the curved surfaces of the bottom surfaces of the U-shaped guide grooves on the at least two guide claws force the band body of the band to bend, and the elastic potential energy generated by the bending of the band body of the band can enable the head of the band to automatically fall into the sinking pit on the frame for positioning.

The fact that the bottom surface of the narrower U-shaped guide groove on the frame is arranged to be an inclined plane in the length direction means that the bottom surface of the narrower U-shaped guide groove on the frame forms a certain angle with the bottom surface of the wider U-shaped guide groove on the frame in the length direction.

Utilize the bent produced potential energy of ribbon area body, ribbon head in motion, ribbon head top surface can hug closely the operation of the broad U type guide tank bottom of frame, the pit just sets up based on this characteristic, sets up simply the pit just can replace the setting motion part to dodge ribbon afterbody or block the ribbon head and prevent that the ribbon head from retreating.

Respectively, when the at least two guide claws and the machine frame are in a closed state, and compressed air pushes the ribbon to run in the guide rail, namely in a movement state of the ribbon, the curved surface or the inclined plane of the bottom surface of the narrower U-shaped guide groove on the machine frame and the curved surface of the bottom surface of the U-shaped guide groove on the at least two guide claws force the ribbon body to bend, and the elastic potential energy of the bending of the ribbon body can enable the head of the ribbon to automatically fall into a pit on the machine frame to be positioned; the back side of the sinking pit can prevent the head of the ribbon from retreating.

When the at least two guide claws and the machine frame are in a closed state, after the head of the ribbon falls into the pit on the machine frame, in a static state of the ribbon, the elastic potential energy of the bending of the ribbon body of the ribbon forces the top surface of the head of the ribbon to be clung to the bottom surface of the pit on the machine frame; the back side of the sinking pit can prevent the head of the ribbon from retreating.

The rear end face of the ribbon head and the top face of the ribbon head are generally provided with a fillet radius of 0.2-0.3mm, and in order for the pit to prevent the ribbon head from retreating, the depth of the pit (namely the rear side face of the pit) needs to be higher than the fillet radius between the top face of the ribbon head and the rear end face of the ribbon head, so that the depth of the pit is at least more than 0.4 mm.

Considering that the thickness of the head of the ribbon has a certain tolerance, a small amount of clearance such as 0.1mm thickness tolerance is also designed, so that when the head of the ribbon falls into the pit of the frame, the elastic potential energy of the bending of the ribbon body of the ribbon forces the top surface of the head of the ribbon to be closely attached to the bottom surface of the pit on the frame, and the cumulative calculation can be known: 0.4+0.1=0.5 mm, namely when the ribbon head falls into the pit of the frame and is in a static state, the ribbon head and the end face of the nearer guide claw in the closed state are provided with a gap, and the thickness of the gap is at least more than 0.5 mm.

The technical scheme of this patent is applicable to not only disjunctor ribbon but also to vibration pay-off's bulk ribbon.

The invention has the beneficial effects that:

the bottom surface of a narrower U-shaped guide groove on the frame is designed to be a curved surface or an inclined plane, and the bottom surface of the U-shaped guide groove of the guide claw is designed to be a curved surface, and the curved surface or the inclined plane is utilized to force the band body and the band tail of the band to deform in the running process and in the static state, so that the plane structures (unsteady state) of the band body and the band tail of the band are converted into a three-dimensional structure, and the stability of the band in the moving state and the static state is improved;

the bottom surface of a narrower U-shaped guide groove on the frame is designed to be a curved surface or an inclined plane, and the bottom surface of the U-shaped guide groove of the guide claw is designed to be a curved surface, and the curved surface or the inclined plane is utilized to force the band body and the tail part of the band to deform in the running process and in a static state, so that the band body accumulates certain elastic potential energy, the head part of the band is forced to automatically fall into a sinking pit on the frame to be positioned, and the reliability of band positioning is improved;

the narrower U-shaped guide groove bottom surface on the frame is designed into a curved surface or an inclined plane and a combination of a pit designed on the frame, the elastic potential energy of the binding belt is skillfully utilized to realize the scheme of realizing accurate positioning of the binding belt head in a moving state and a static state, compared with the prior art, the method is simpler and more efficient, meanwhile, the compatibility of the thickness tolerance of the binding belt head is stronger, and the compatibility of the automatic binding tool to the tolerance of the binding belt head is greatly improved.

Drawings

FIG. 1 is a back view of a compressed air fed automatic strapping tool with the housing removed;

FIG. 2 is a cross-sectional view C-C corresponding to FIG. 1, with a working center plane of a compressed air fed automatic strapping tool cut away;

FIG. 3 is a sectional E-E view corresponding to FIG. 3;

FIG. 4 is a cross-sectional view C-C corresponding to FIG. 2, with the work center plane cut away, showing curves along the length of the interior cavity of the rail;

FIG. 5 is an enlarged partial cross-sectional view of D-D corresponding to FIG. 3;

FIG. 6 is an enlarged partial cross-sectional view of G-G corresponding to FIG. 4;

FIG. 7 is an enlarged view of a portion of region R corresponding to FIG. 3, showing a wide U-shaped guide slot on the frame where the wide and narrow U-shaped guide slots are joined, the pit being formed by a subtractive process; the tail part of the binding belt enters a narrower U-shaped guide groove on the frame to be forced to bend;

FIG. 8 is an enlarged view of a portion of region R corresponding to FIG. 3 showing the movement of the tie strap body in the U-shaped guide slots of the at least two guide jaws, the tie strap head being about to enter the pit in the frame;

FIG. 9 is an enlarged view of a portion R corresponding to FIG. 3 showing the band body and tail running in the U-shaped guide slots of the at least two guide jaws and being forced to bend, the bent band body creating elastic potential energy tending to extend outwardly;

FIG. 10 is an enlarged view of a portion R corresponding to FIG. 3 showing the tie head positioned in the pit, the elastic potential energy generated by the curved tie body forcing the top surface of the tie head against the bottom surface of the pit on the frame;

FIG. 11 is an enlarged view of a portion of the R region corresponding to FIG. 3, showing the placement of triangular entities (feed patterns) at the bottom of the wider U-shaped guide slot of the frame, resulting in a functional equivalent of the pit formed by the subtractive patterns shown in FIGS. 7-10;

FIG. 12 is a view showing the guide rail as a square tubular member;

fig. 13 shows the prior art scheme described in the background art: the swinging elastic locking part is designed, and the elastic pushing locking part of the spring is utilized to lock the head of the ribbon.

Reference numerals: 1. a guide rail; 10. a guide U-shaped piece; 11. a cover plate; 15. an electric or pneumatic motor; 2. a pull-through cutting combined mechanism; 20. an inner cavity (of the rail); 21. a first guide claw; 210. the first guide claw rotates the center pin; 211. u-shaped guide grooves of the first guide claws; 2111. the bottom surface of the U-shaped guide groove of the first guide claw; 22. a second guide claw; 221. u-shaped guide grooves of the second guide claws; 2211. the bottom surface of the U-shaped guide groove of the second guide claw; 222. a second guide jaw end face; 23. a frame; 230. sinking pit; 231. a step; 232. the bottom surface of the pit; 233. the rear side surface of the pit; 234. a wider U-shaped guide groove; 2341. the bottom surface of the wider U-shaped guide groove; 235. narrower U-shaped guide slots; 2351. the bottom surface of the narrower U-shaped guide groove; 236. triangle entity; 24. a pulley; 3. a tie; 31. a tie head; 311. the front end face of the head of the ribbon; 312. the top surface of the head of the ribbon; 313. the rear end face of the head of the ribbon; 32. a strapping tape body; 33. the tail part of the ribbon; 5. a pulley-pulling transmission system; g0, triangle body height; g2, clearance between the tie head and the nearer end face of the guide jaw.

Detailed Description

The invention is further described below with reference to the drawings and detailed description.

As shown in fig. 1, 2, 3, 4, 5, 6 and 12, a compressed air fed automatic strapping tool removes or conceals a housing and other components (e.g., a cutter, a portion of a drive assembly, etc.) identical to those of prior art strapping tools, comprising at least: a guide rail 1 and a pull-through cutting combined mechanism 2; as shown in fig. 5 and 6, the guide rail 1 is designed as a combination of the guide rail U-shaped member 10 and the cover plate 11 or is designed as an integrally formed part of the guide rail U-shaped member 10 and the cover plate 11, and as shown in fig. 12, the guide rail 1 is designed as an integrally formed square tubular shape; the inner cavity 20 of the guide rail 1 in fig. 2 is designed into a straight line section in the length direction, the inner cavity 20 of the guide rail 1 in fig. 4 is designed into a combination of the straight line section and the curved line section in the length direction, and the inner cavity 20 of the guide rail 1 is preferentially designed into the combination of the straight line section and the curved line section in the length direction due to the need of avoiding other moving parts; as shown in fig. 2, 3 and 4, the cross-section of the cavity 20 of the guide rail 1 is larger than the cross-section of one of the tie heads 31 and the cross-section of the cavity 20 can only accommodate at most no more than one tie head 31 with clearance (the cross-section of the cavity of the curved section of the guide rail allows a design to be larger).

If the guide rail 1 is designed as a combination of the guide rail U-shaped member 10 and the cover plate 11 as shown in fig. 5 and 6, the joint surface of the guide rail U-shaped member 10 and the cover plate 11 is preferably arranged to be parallel to the main central surface of the automatic strapping tool for feeding compressed air from the viewpoint of processing convenience, and the joint surface of the guide rail U-shaped member 10 and the cover plate 11 as shown in fig. 5 and 6 is parallel to the C-C section of fig. 1, which is the main central surface of the automatic strapping tool for feeding compressed air from the viewpoint of processing convenience.

The guide rail 1 shown in fig. 1 to 11 is made of hard or soft material; the guide rail 1 shown in fig. 12 is formed in an integrally formed tubular shape from a hard or soft material, and the end surface of the guide rail 1 shown in fig. 12 may be directly connected to the wider U-shaped guide groove 234 of the frame 23 shown in fig. 2 or 3.

And the guide rail 1 and the frame 23 are connected in sequence, and the inner cavity 20 of the guide rail 1 is communicated with the wider U-shaped guide groove 234 of the frame 23; compressed air is communicated into the inner cavity 20 of the guide rail 1, the binding belt 3 runs in the inner cavity 20 of the guide rail 1 under the pushing of the compressed air, and the tail part of the binding belt passes through the wider U-shaped guide groove 234 of the frame 23, then enters the U-shaped guide groove 211 of the first guide claw 21 and then enters the U-shaped guide groove 221 of the first guide claw 22; the tie head 31 enters the wider U-shaped guide slot 234 of the frame 23.

As shown in fig. 2, 4, and 7 to 11, the pull-through and cut-out combined mechanism 2 at least includes a frame 23, at least two guide claws (a first guide claw 21 and a second guide claw 22) and a pulley 24, wherein U-shaped guide grooves 211 and 221 for guiding the tie strap body 32 are respectively provided inside the at least two guide claws (the first guide claw 21 and the second guide claw 22), the U-shaped guide grooves 211 and 221 of the at least two guide claws (the first guide claw 21 and the second guide claw 22) are lengths of the U-shaped guide grooves of the at least two guide claws (the first guide claw 21 and the second guide claw 22) formed by scanning along a curve, (i.e., the U-shaped guide groove bottom surface 2111 of the first guide claw 21 is a curved surface, and the U-shaped guide groove bottom surface 2211 of the second guide claw 22 is a curved surface); the frame 23 is provided with a wider U-shaped guide groove 234 for guiding the ribbon head 31 and a narrower U-shaped guide groove 235 for guiding the ribbon body 32, the narrower U-shaped guide groove 235 on the frame 23 can only allow the ribbon body 32 to pass through but not allow the ribbon head 31 to pass through, the bottom surface 2351 of the narrower U-shaped guide groove 235 on the frame 23 is designed into a curved surface or an inclined plane, the wider U-shaped guide groove 234 on the frame 23 is connected with the narrower U-shaped guide groove 235 in the head-tail direction in the length direction, and the wider U-shaped guide groove 234 and the narrower U-shaped guide groove 235 are in butt joint to form two steps 231 due to different widths of the wider U-shaped guide groove 234 and the narrower U-shaped guide groove 235, and the bottom of the wider U-shaped guide groove 234 on the frame 23 is also provided with a sink 230, and the sink 230 is arranged at the position where the wider U-shaped guide groove 234 and the narrower U-shaped guide groove 235 on the frame 23 are connected; the purpose of the pit 230 is to locate the tie head 31 within the pit 230 and to prevent the tie head 31 from backing out.

As shown in fig. 2, 4 and 7-11, the narrower U-shaped guide groove 235 on the frame 23 is communicated with the U-shaped guide groove 211 of the first guide claw, and the wider U-shaped guide groove 234 on the frame 23 is communicated with the inner cavity 20 of the guide rail 1; after the at least two guide claws (the first guide claw 21 and the second guide claw 22) are closed with the frame 23, the U-shaped guide grooves 211 and 221 of the at least two guide claws (the first guide claw 21 and the second guide claw 22) form a closed loop or an incompletely closed loop with the wider U-shaped guide groove 234 and the narrower U-shaped guide groove 235 on the frame 23; the compressed air can push the tie 3 to move in the inner cavity 20 of the guide rail 1.

As shown in fig. 7, when the strap tail 33 (shown in phantom) enters the narrower U-shaped guide slot 235 in the frame 23, the curved or beveled shape of the narrower U-shaped guide slot bottom surface 2351 forces the strap tail 33 to bend and ride against the narrower U-shaped guide slot bottom surface 2351 in the frame 23, and further, as shown in fig. 8-10, when the strap tail 33 enters the U-shaped guide slots 211 and 221 of the at least two guide jaws (first guide jaw 21 and second guide jaw 22); the curved surfaces or inclined planes of the bottom surface 2351 of the narrower U-shaped guide groove on the frame 23, the bottom surface 2111 of the U-shaped guide groove of the first guide claw 21 and the bottom surface 2211 of the U-shaped guide groove of the second guide claw 22 force the tie body 32 to bend, and the tie body 32 tends to return to the original straightened state due to certain elasticity of the tie body 32, namely the elastic potential energy accumulated on the tie body 32, as shown in fig. 9, the elastic potential energy generated by the forced bending of the tie body 32 causes the tie head 31 and the tie tail 33 to spring open in the directions indicated by arrows U and H in the moving state and the static state of the tie; when the at least two guide claws and the frame 23 are in a closed state, and compressed air pushes the ribbon to run in the guide rail, namely the ribbon 3 is in a moving state, the elastic potential energy of the bending of the ribbon body 32 can enable the top surface 312 of the ribbon head to abut against the bottom surface 2341 of the wider U-shaped guide groove on the frame 23, and when the front end surface 311 of the ribbon head is pushed to the two steps 231 formed by connecting the wider U-shaped guide groove 234 and the narrower U-shaped guide groove 235 on the frame 23, the two steps push against two sides of the front end surface 311 of the ribbon head and prevent the ribbon head from continuously advancing; the elastic potential energy of the bending of the ribbon body 32 forces the ribbon head 31 to automatically fall into the sinking pit 230 of the frame 23 for positioning, and the sinking pit rear side 233 can prevent the ribbon head 31 from retreating; as shown in fig. 10, after the band head 31 falls into the pit 230 on the frame, the band 3 is at rest, so long as the at least two guide claws and the frame 23 are in a closed state, elastic potential energy generated by bending the band body 32 forces the top surface 312 of the band head to cling to the bottom surface 232 of the pit on the frame 23, and the rear side surface 233 of the pit can prevent the band head 31 from backing.

As shown in fig. 10, when the tie head 31 is positioned in the pit 230, the first guide jaw 21 of the at least two guide jaws can swing around the first guide jaw rotation center pin 210 to penetrate the tie tail 33 into the hole of the tie head 31, and during the swing of the first guide jaw 21, the tie head 31 receives a backward force, and the pit rear side 233 can block the tie head rear end surface 313 to prevent the tie head 31 from backward moving.

The specific description is as follows: the design of the narrower U-shaped guide slot bottom surface 2351 of the frame 23 into a curved shape or a bevel has several important roles in the length direction: first, the curve connection transition from the wider U-shaped guide groove 234 on the frame 23 to the U-shaped guide groove 211 of the first guide claw can be realized (the circle forming the guide groove distributes the curvature on a plurality of parts to avoid the rapid change of the curvature); secondly, the band tail 33 can be forced to bend, and a certain elastic potential energy is accumulated in the bending part of the band tail 33 when the band tail 33 is forced to bend (the bending part of the band tail 33 tends to return to a flat state), and the inherent elastic potential energy enables the band tail 33 to be tightly attached to the bottom surface 2351 of the narrower U-shaped guide groove on the frame 23 so as to play a role in guiding the band tail 33; thirdly, the elastic potential energy of the tail part 33 of the ribbon and the ribbon tail part 33 just coming out of the inner cavity 20 of the guide rail 1 can maintain a certain arc shape, so that the running stability of the tail part 33 of the ribbon and the ribbon body 32 of the ribbon can be improved (the tail part 33 of the ribbon and the ribbon body 32 are of plane structures and are easy to swing under the influence of air flow in high-speed movement, the curved surface or inclined plane of the bottom surface 2351 of the narrower U-shaped guide groove on the frame 23 forces the tail part 33 of the ribbon or the ribbon body 32 to bend and then become a three-dimensional structure, so that the ribbon is more stable), the tail part 33 of the ribbon can be prevented from floating out of the narrower U-shaped guide groove 235 on the frame 23, and once the tail part 33 of the ribbon is floating out of the narrower U-shaped guide groove on the frame 23, the tail part 33 of the ribbon can interfere with the strapped object, so that the ribbon 3 can not be sent to the correct position and the ribbon fails.

The design of the narrower U-shaped guide groove bottom surface 2351 on the frame 23 in a lengthwise direction to be inclined also allows the band body to bend to generate elastic potential energy, but in theory (from the angle of contact pressure), the design of the U-shaped guide groove bottom surface 2351 in a lengthwise direction to be curved will result in less contact pressure angle to the tip of the band tail at the moment the U-shaped guide groove bottom surface 2351 contacts the band tail, and therefore, the design of the narrower U-shaped guide groove bottom surface 2351 on the frame 23 in a lengthwise direction will result in less impact to the band tail at the moment the narrower U-shaped guide groove bottom surface 2351 on the frame 23 in a lengthwise direction, and therefore, preferably, the design of the narrower U-shaped guide groove bottom surface 2351 in a lengthwise direction is curved.

Supplementary explanation about at least two guide jaws: to achieve automatic strapping requires at least two guide jaws, designated in this patent as a first guide jaw 21 and a second guide jaw 22, the second guide jaw 22 being rotatable about a fixed axis or movable in its entirety to allow the strapping object to enter the closed or incompletely closed loop; when the band body of the band 3 enters the U-shaped guide groove 211 of the first guide claw 21 and the U-shaped guide groove 221 of the second guide claw 22 and the band head 31 is positioned by the wider U-shaped guide groove 234 positioned in the frame 23, the first guide claw 21 can swing around the first guide claw rotation center pin 210 to penetrate the band tail 33 into the hole of the band head 31; the two guide claws are designed to achieve the most basic and common bundling function, but in some special cases (such as requiring the bundling belt to pass through a small hole and a small space), the first guide claw 21 and the second guide claw 22 need to be respectively designed into multiple sections, which will not be described in detail herein.

Further, as shown in fig. 2, 4, and 7 to 11, the at least two guide claws (the first guide claw 21 and the second guide claw 22) and the pulley 24 are driven by the motor 15, or driven by a cylinder through rack-and-pinion conversion, or driven by the air motor 15.

As shown in fig. 2, 4 and 7 to 10, the rear end surface 313 of the tie head and the top surface 312 of the tie head are generally provided with injection-molded fillets of 0.2-0.3mm, and if the pit 230 is to be provided to prevent the tie head 31 from retreating, the depth of the pit 230 (i.e., the height of the pit rear side surface 233) needs to be higher than the fillets between the top surface 312 of the tie head and the rear end surface 313 of the tie head, and thus the depth of the pit 230 (i.e., the height of the pit rear side surface 233) is at least 0.4mm or more.

As shown in fig. 10, when the band head 31 falls into the pit 230 of the frame 23, the elastic potential energy generated by the forced bending of the band body 32 causes the band head 31 and the band tail 33 to spring outwards in the moving state and the static state of the band, so that the top surface 312 of the band head will be close to the pit bottom surface 232 of the pit 230, and the band head 31 and the end surface of the nearer guide jaw (i.e. the second guide jaw end surface 222) of the at least two guide jaws (the first guide jaw 21 and the second guide jaw 22) have a gap G2, and the thickness of the gap G2 is at least 0.5 mm.

Pit 230 as shown in fig. 2, 4, and 7 to 10 is formed by digging (material-reducing manner) a wide U-shaped guide groove bottom surface 2341 on frame 23: the pit 230 shown in fig. 11 is formed by adding a triangular entity 236 (feeding mode) to the bottom surface 2341 of the wider U-shaped guide groove 234, and the height of the triangular entity 236 shown in fig. 11 is G0, G0 is not less than 0.4mm; the height G0 of the triangular solid 236 shown in fig. 11 is the height of the pit backside 233.

Regardless of the pit 230 formed by the charging or the subtracting method, the final function of the pit 230 formed by the charging or subtracting method is the same, namely: when the ribbon head 31 falls into the pit 230 of the frame 23, the elastic potential energy generated by the ribbon body 32 being forced to bend causes the ribbon head 31 and the ribbon tail 33 to have a tendency to spring outwards in both a moving state and a static state, so that the top surface 312 of the ribbon head clings to the pit bottom surface 232 of the pit 230, the height of the pit rear side surface 233 is not less than 0.4mm, and the thickness tolerance of the ribbon head (0.1 mm is reserved as the tolerance margin of the ribbon head) is considered; therefore, regardless of the pit 230 formed by the feeding or subtracting method, the band head 31 and the end face of the nearer one of the at least two guide claws (the first guide claw 21 and the second guide claw 22) (i.e., the second guide claw end face 222) have a gap G2 (g2=0.4+0.1), and the thickness of the gap G2 is at least 0.5mm or more.

As described in the background of the present specification: the present inventors set forth in a number of prior patents: the method for locking the head of the ribbon by the root or the end face of the second guide claw is that a small-angle inclined plane (which is opposite to the surface of the frame to form a wedge shape) is designed on the end face of the root of the second guide claw, the ribbon is punched into a wedge-shaped cavity at a high speed, and the head of the ribbon is locked by the end face of the root of the second guide claw.

FIG. 13 is a partial screenshot of a design solution commonly employed in the prior art to prevent the tie head from backing (the inventor also employs a number of prior patents, but does not specify nor disclose related pictures), although the details of the various specific designs of the prior art differ slightly, but all use the spring elasticity to avoid the tie head as it passes, the spring pushing the part back against the tie head after the tie head passes, and its working principle is the same as that shown in FIG. 13; in fig. 13, a blocking block 45 is designed to swing around a pin 44, the tie head 31 is pushed by compressed air to impact the side surface of the blocking block 45 at a high speed to force the blocking block 45 to compress a spring 46, so that the tie head 31 passes through, after the tie head 31 passes through, the blocking block 45 is forced to return under the action of the spring 46 and the end of the blocking block 45 can bear against the tie head 31 to prevent the tie head 31 from retreating. As described in the background of the present specification, such designs have problems: the different speed of the ribbon, the different positions of the touch points and the different thickness of the ribbon head 31, which all cause the kinetic energy loss of the blocking piece 45 to the ribbon movement, but the difference of the kinetic energy loss is difficult to calculate and measure, the repeatability and consistency of test data are poor, and finally the ribbon head 31 cannot accurately reach the ideal positioning position; in addition, the tie may carry a lot of plastic debris into the crevices around the stop block 45, often because the debris catches the stop block 45, causing its movement function to fail entirely.

In fig. 13, the element 19 is also designed in a swinging manner in order to avoid the tie tail 33. In the prior art, a plurality of parts are designed into movable parts, the mechanism is complicated on the surface, the technical content is high, but the design is not optimized in practice, and no better solution is found in the technical solution of the prior patent.

Compare this patent technical scheme and current various schemes (including the design that fig. 13 shows) of prior patent, this patent technical scheme is obvious simple (need not to design the moving part), ingenious (utilize the elastic potential energy that the ribbon area body warp produced, be called endogenous power, need not external power, let ribbon "conscious"), but the reliability is higher, does not need frequent cleaning again, maintains, and is stronger to ribbon head thickness tolerance's compatibility moreover. Therefore, compared with the prior art, the technical scheme of the patent has obvious progress and obvious positive effect.

Supplementary explanation: the U-shaped guide groove in the specification is a groove formed by three surfaces and comprises two side surfaces and a bottom surface, wherein the bottom surface is the surface clamped between the two side surfaces; other names in the specification are merely descriptive convenience and are named, for example, the bottom surface may also be referred to as the top surface if the view angle of the part is different; for another example: the U-shaped guide groove is a groove formed by three surfaces, is three straight lines seen from the section of the U-shaped groove, and does not mean that the bottom line is always an arc line like the letter U; the part names or feature names are not absolute limitations on their function; in addition, for the frame 23, from the processing perspective, the optimal design is to split the frame 23 into two pieces to be processed and then combined into a whole, and similarly, other parts have the possibility of splitting, so long as the same functional parts are split or combined, and all the parts fall into the protection scope of the patent.

Those skilled in the art can also make appropriate changes and modifications to the above-described embodiments in light of the foregoing disclosure and description of the invention. Therefore, the invention is not limited to the specific embodiments disclosed and described above, but rather, simple modifications and changes of the invention, especially for accomplishing the same functions, may be made by simple disassembly or assembly of parts, which shall fall within the scope of the claims of the invention. In addition, although specific terms are used in the present specification, these terms are for convenience of description only and do not limit the present invention in any way.

Claims (8)

1. An automatic ribbon instrument of compressed air pay-off, its characterized in that: comprising the following steps: the guide rail and the pull-through cutting combined mechanism; the guide rail is internally provided with an inner cavity capable of accommodating the head part of the ribbon, the guide rail is formed by combining two parts or is a square tubular part formed integrally, and the inner cavity of the guide rail is designed into a straight line or is formed by combining a straight line section and a curve section in the length direction; the threading, pulling and cutting combined mechanism comprises a frame, at least two guide claws and a strap wheel, wherein U-shaped guide grooves for guiding the strap body of the strap are formed in the at least two guide claws, and the bottoms of the U-shaped guide grooves on the at least two guide claws are curved surfaces in the length direction; the machine frame is provided with a wider U-shaped guide groove for guiding the head of the ribbon and a narrower U-shaped guide groove for guiding the ribbon body, the narrower U-shaped guide groove in the machine frame can only allow the ribbon body to pass through but not allow the ribbon head to pass through, the bottom surface of the narrower U-shaped guide groove in the machine frame is set into a curved surface or an inclined plane in the length direction, the wider U-shaped guide groove in the machine frame is connected with the narrower U-shaped guide groove in the length direction in a head-tail mode and forms two steps, a pit is arranged at the bottom of the wider U-shaped guide groove in the machine frame, and the pit is arranged at the connecting position of the wider U-shaped guide groove and the narrower U-shaped guide groove in the machine frame; the narrower U-shaped guide groove on the rack is communicated with the U-shaped guide grooves of the at least two guide claws in a sequential way, and the wider U-shaped guide groove on the rack is communicated with the inner cavity of the guide rail; after the at least two guide claws are closed with the rack, the U-shaped guide grooves of the at least two guide claws are formed into a closed loop or an incompletely closed loop with the wider U-shaped guide grooves and the narrower U-shaped guide grooves on the rack; the inner cavity of the guide rail can be communicated with compressed air, the compressed air can push the front end face of the head of the ribbon to two steps formed by connecting a wider U-shaped guide groove with a narrower U-shaped guide groove on the frame, and the two steps are propped against two sides of the front end face of the head of the ribbon and do not allow the head of the ribbon to continuously advance; the elastic potential energy generated by bending the band body of the band is forced under the action of the curved surface or the inclined plane of the bottom surface of the narrower U-shaped guide groove on the frame and the curved surfaces of the bottom surfaces of the U-shaped guide grooves on the at least two guide claws, so that the head of the band can automatically fall into a pit on the frame to be positioned.

2. An automatic strapping tool with compressed air feed according to claim 1 wherein: when the at least two guide claws and the machine frame are in a closed state, after the head of the ribbon falls into the pit on the machine frame, the top surface of the head of the ribbon is forced to be clung to the bottom surface of the pit on the machine frame by elastic potential energy of bending of the ribbon body in a static state of the ribbon.

3. An automatic strapping tool with compressed air feed according to claim 1 wherein: when the at least two guide claws and the machine frame are in a closed state, compressed air pushes the head of the ribbon to automatically fall into a pit on the machine frame in a moving state, and the rear side surface of the pit can prevent the head of the ribbon from retreating.

4. An automatic strapping tool with compressed air feed according to claim 1 wherein: when the at least two guide claws and the machine frame are in a closed state, and when the head of the ribbon falls into the sinking pit on the machine frame, the rear side surface of the sinking pit can prevent the head of the ribbon from retreating in a static state of the ribbon.

5. An automatic strapping tool with compressed air feed according to claim 1 wherein: when the ribbon head falls into the pit of the frame and is in a static state, a gap is formed between the ribbon head and the end face of the nearer guide claw of the at least two guide claws in a closed state, and the thickness of the gap is at least more than 0.5 mm.

6. An automatic strapping tool with compressed air feed according to claim 1 wherein: the guide rail is made of hard materials or soft materials.

7. An automatic strapping tool with compressed air feed according to claim 1 wherein: the automatic strapping tool capable of feeding compressed air is suitable for a conjoined strapping tape or a bulk strapping tape.

8. An automatic strapping tool with compressed air feed according to claim 1 wherein: when the guide rail is formed by combining two parts, the joint surface of the two parts of the guide rail is parallel to the main central surface of an automatic strapping tool fed by compressed air.