A strapping head for a strapping machine

Abstract

The present invention discloses a packing head for a packing machine, which includes a conveying and tensioning unit and a connecting unit mounted on a frame; the connecting unit is used for welding the overlapping part of the head and tail ends of the packing belt; the conveying and tensioning unit includes a high-tension driving pulley, a first pressing wheel assembly that cooperates with the high-tension driving pulley to form a first packing belt passage, a low-tension driving pulley, and a second pressing wheel assembly that cooperates with the low-tension driving pulley to form a second packing belt passage; the first pressing wheel assembly includes a first lever and a driven wheel structure and a guiding free wheel respectively hinged at both ends of the first lever; a first tension spring is connected to one side of the first lever close to the guiding free wheel. The present invention uses the first tension spring to pull the first lever of the first pressing wheel assembly, realizing the separation of the first pressing wheel assembly from the high-tension driving pulley, and can ensure that the packing belt is not affected by the high-tension driving pulley during the process of the low-tension driving pulley conveying the packing belt, guaranteeing the fast and effective conveying of the packing belt.

Description

Technical Field

[0001] The present invention relates to the technical field of packing machines, and particularly to a packing head for a packing machine. Background Art

[0002] A packing machine is a device used to bind a packing belt on the surface of an article, generally including a frame and a packing head. In the process of realizing automatic packing, the packing head has to go through several steps such as tape feeding, tape feeding in place, pressing the head end (free end), tape retracting, pressing the tail end (infinite length end), welding and cutting the tape, tape discharging, and head resetting. In order to complete all these steps, the packing head needs to be composed of structures such as a tape feeding device, a tape retracting device, a joint connecting and cutting device, a transmission system, a track frame, and a control device. Therefore, the packing head is the core component in the whole packing machine. In the prior art, there are also designs and applications for the packing head, but there are still some places that need to be improved.

[0003] During the process of the packing machine transporting the packing belt, usually only one driving pulley is included, which rotates forward during tape feeding and rotates backward during tape retracting. In both the tape feeding and tape retracting processes, sufficient friction between the driving pulley and the packing belt is required to drive the packing belt to move. In order to make there be sufficient friction between the packing belt and the driving pulley, a pressing wheel is generally provided, and the pressing wheel usually adopts a spring mechanism to achieve the pressing effect. However, during the processes of tape feeding and tape retracting, the requirements for the pressing degree of the packing belt are different. If it is in a high-pressure state all the time, it is not conducive to rapid tape feeding during the tape feeding process. If it is in a low-pressure state all the time, the high-tension pressing during the tape retracting process cannot be completed.

[0004] Chinese Patent with the application publication number of CN 112027238 A discloses a strapping and packing machine. This solution is provided with a tape feeding wheel and a pressing wheel, and the pressing wheel presses the packing belt on the tape feeding wheel through a connecting rod. However, this solution does not clearly record how to realize the pressing process. According to the records of the prior art, it can only be obtained that it relies on a spring to apply a certain elastic force or tensile force, and then can push or pull the connecting rod to realize the pressing effect of the pressing wheel. Therefore, this solution only applies the prior art's application of the spring. If you want to increase the pressing force of the pressing wheel, you can only improve it in the direction of improving the spring, such as replacing a spring with a larger spring constant or increasing the deformation degree of the spring. If you want to reduce the pressing force of the pressing wheel, you can replace a spring with a smaller spring constant or reduce the deformation degree of the spring. However, no matter which change is made, only one pressing state can be provided, and it cannot be adjusted in real time according to different working conditions of tape feeding and tape retracting.

[0005] The Chinese patent with the authorization announcement number CN 212501203 U discloses an integrated packing head and a packing device. In this solution, a driving wheel for conveying the packing belt is provided, and a pressing component is provided. The pressing component is used to press the packing belt against the surface of the driving wheel to ensure smooth conveyance and avoid slipping. The pressing component includes a wheel seat, a pressing wheel, and a pressing spring. The pressing wheel is pressed against the driving wheel by the elastic force of the pressing spring. However, the elastic force of the spring is limited, and only by increasing the elastic coefficient and deformation degree of the spring can the pressing force be increased, but the actual effect is not ideal. Similarly, this solution cannot adjust the pressing state of the pressing component in real time according to different working conditions of belt feeding and belt winding.

[0006] As can be seen from the above solution, in the prior art, the pressing structure for the driving pulley cannot be adjusted according to the working conditions, so the pressing state cannot be changed, and a good belt feeding and belt winding effect cannot be achieved. Therefore, how to achieve different pressures on different driving pulleys under different working conditions of belt feeding and belt winding is a technical problem to be solved urgently. Summary of the Invention

[0007] The object of the present invention is to provide a packing head for a packing machine to solve the above problems existing in the prior art. A first pressing wheel assembly and a second pressing wheel assembly are respectively arranged in cooperation with a high-tension driving pulley and a low-tension driving pulley. The first lever of the first pressing wheel assembly is pulled by a first tension spring to realize the separation of the first pressing wheel assembly from the high-tension driving pulley, so that the low-tension driving pulley will not be affected by the high-tension driving pulley during the process of conveying the packing belt, ensuring the fast and effective conveyance of the packing belt.

[0008] To achieve the above object, the present invention provides the following solution:

[0009] The present invention provides a packing head for a packing machine, including a conveying and tensioning unit and a connecting unit installed on a frame;

[0010] The connecting unit includes a head clamping knife, a tail clamping knife, and a welding head. The head clamping knife and the tail clamping knife are respectively located on the moving track of the packing belt conveyed by the conveying and tensioning unit, and respectively clamp the head and tail of the packing belt. The welding head is used to weld the overlapping part of the head and tail ends of the packing belt;

[0011] The conveying and tensioning unit includes a high-tension driving pulley, a first pressing wheel assembly that cooperates with the high-tension driving pulley to form a first packing belt channel, a low-tension driving pulley, and a second pressing wheel assembly that cooperates with the low-tension driving pulley to form a second packing belt channel; the first pressing wheel assembly includes a first lever and a driven wheel structure and a guiding free wheel respectively hinged at both ends of the first lever; the packing belt sequentially passes through the first packing belt channel, the second packing belt channel and adheres to the guiding free wheel for belt feeding and taking-up; a first tension spring is connected to one side of the first lever close to the guiding free wheel, and the first tension spring is used to pull the first lever to drive the driven wheel structure away from the high-tension driving pulley.

[0012] Preferably, the second pressing wheel assembly includes a second lever, one end of the second lever is hinged with a pressing wheel structure, the other end of the second lever is connected with a second tension spring, a second rotating shaft is arranged on one side of the second lever close to the pressing wheel structure, and the second tension spring is used to pull the second lever to drive the pressing wheel structure close to the low-tension driving pulley.

[0013] Preferably, a welding motor is installed on the frame, and the welding motor is power-connected to the welding head.

[0014] Preferably, the high-tension driving pulley is connected with a high-tension servo motor, the low-tension driving pulley is connected with a low-tension servo motor, and both the high-tension servo motor and the low-tension servo motor are installed on the frame.

[0015] Preferably, the connecting unit includes a cam-link structure and a first baffle that respectively cooperate with the head clamping knife, the tail clamping knife and the welding head in the working position;

[0016] The cam-link structure includes a link and a cam and a spring connected to the same side of the rotating shaft on the link, the actions of the cam and the spring on the rotating direction of the link are opposite, the end of the link is connected with an operating structure, the spring can make the operating structure move towards the working position, and the cam can make the operating structure move away from the working position;

[0017] The link includes a first link, a second link and a third link, the cam includes a first cam, a second cam and a third cam, the spring includes a first spring, a second spring and a third spring, and the operating structure includes a welding head, a tail clamping knife and a head clamping knife.

[0018] Preferably, the cam-link structure is power-connected to a position control motor.

[0019] Preferably, a tape groove assembly is provided at the tape outlet end of the guiding free wheel. The tape groove assembly includes an L-shaped base, L-shaped baffles on both sides of the L-shaped base, and a tape return baffle outside the L-shaped base. A tape feeding channel and a tape returning channel are respectively formed on the inner side and the outer side of the L-shaped base, and a packing tape overlapping section is formed at the intersection of the extension lines of the tape feeding channel and the tape returning channel.

[0020] Preferably, a tube positioning strip is provided at the inlet of the tape feeding channel. The packing tape is located between the tube positioning strip and the L-shaped base. A turning bottom tape head is provided at the outlet of the tape feeding channel, and a turning top tape head is provided at the outlet of the tape returning channel.

[0021] Preferably, a short tape inlet groove is provided at the tape inlet end of the first packing tape channel, and the short tape inlet groove is provided with an arc-shaped pointed nozzle facing the first packing tape channel.

[0022] Preferably, a special-shaped connecting and turning tape groove is provided at the tape inlet end of the second packing tape channel, and the special-shaped connecting and turning tape groove is used to connect the first packing tape channel and the second packing tape channel.

[0023] The present invention has achieved the following technical effects compared with the prior art:

[0024] (1) The present invention is provided with a high-tensile driving pulley and a low-tensile driving pulley, which are respectively provided with a first pressing wheel assembly and a second pressing wheel assembly. The first lever of the first pressing wheel assembly is pulled by the first tension spring to separate the first pressing wheel assembly from the high-tensile driving pulley, so that the low-tensile driving pulley can convey the packing tape without being affected by the high-tensile driving pulley during the conveying process, ensuring the fast and effective conveying of the packing tape;

[0025] (2) The present invention uses the second tension spring to provide a certain tension to the second lever, so that the pressing wheel structure can press the packing tape against the low-tensile driving pulley, thereby avoiding the packing tape from slipping when the low-tensile driving pulley runs;

[0026] (3) The present invention is provided with a welding head for welding and connecting the packing tape. The welding head is driven by a cam-link structure. The cam-link structure includes a first link, a first cam and a first spring connected to the same side of the rotating shaft on the first link. The first spring can always be in a stretched state, and the packing tape is welded by using the cooperation between the welding head and the first baffle with the tension force, which can give full play to the advantages of the spring, avoid bending deformation, ensure a stable pressing state, and further improve the welding effect;

[0027] (4) The present invention provides power for the welding head by setting a welding motor, controls the position of the cam-linkage structure through a position control motor to control the action states of the welding head, head clamping knife, tail clamping knife, middle clamping knife, etc., provides a low tension for the conveying or tensioning of the packing belt through a low-tension servo motor, and provides a high tension for the tensioning of the packing belt through a high-tension servo motor. In short, by controlling the operation of different structures or components in the packing head through different motors, the system structure can be simplified and the level of automatic control can be improved;

[0028] (5) The present invention forms a belt feeding channel and a belt returning channel for the conveying of the packing belt through an L-shaped base, an L-shaped baffle and a belt returning baffle. Whether the packing belt is conveyed forward or backward, the conveying direction and position of the packing belt can be effectively restricted, ensuring that the packing belt is conveyed along the specified path and providing a structural support for the conveying and tensioning of the packing belt; In addition, by setting a pipe position strip at the entrance of the belt feeding channel, a turning bottom belt head at the exit, and a turning top belt head at the exit of the belt returning channel, the conveying path of the packing belt is further restricted. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0030] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0031] Figure 2 It is a front view structural schematic diagram of the conveying and tensioning unit of the present invention;

[0032] Figure 3 It is a three-dimensional structural schematic diagram of the conveying and tensioning unit of the present invention;

[0033] Figure 4 It is an exploded structural schematic diagram of the high-tension driving pulley and the first pressing wheel assembly of the present invention;

[0034] Figure 5 It is an exploded structural schematic diagram of the low-tension driving pulley and the second pressing wheel assembly of the present invention;

[0035] Figure 6 It is an exploded structural schematic diagram of the grooved component of the present invention;

[0036] Figure 7 It is a sectional structural schematic diagram of the grooved component of the present invention;

[0037] Figure 8 It is a structural schematic diagram of the short grooved belt for feeding of the present invention;

[0038] Figure 9 This is a schematic diagram of the structure of the anisotropically connected steering belt groove of the present invention;

[0039] Figure 10 This is a schematic diagram of the explosion structure of the connection unit of the present invention;

[0040] Figure 11 It is a schematic diagram of the cross-sectional structure of the connection unit of the present invention;

[0041] Figure 12 It is a schematic diagram of the structure of the first connecting rod in the connecting unit of the present invention;

[0042] Figure 13 is a schematic diagram of the structure of the fourth connecting rod in the connecting unit of the present invention;

[0043] Among them, 1. conveying tensioning unit; 2. belt slot assembly; 3. connection unit; 4. low-tension servo motor; 5. high-tension servo motor; 6. position control motor; 7. welding motor;

[0044] 11. High-tension driving pulley; 12. Low-tension driving pulley; 13. First lever; 14. Driven pulley structure; 141. Connecting plate; 142. Driven pulley; 143. Articulated shaft; 15. Guide free wheel; 16. First rotating shaft; 17. First tension spring; 18. High-tension support plate; 19. Pressure pulley; 110. Second lever; 111. Second rotating shaft; 112. U-shaped bracket; 113. Second tension spring; 114. Tension adjustment mechanism; 115. Rotating support plate; 116. Base plate;

[0045] 21. L-shaped base; 22. L-shaped baffle; 23. Bottom steering lead; 24. Top steering lead; 25. Belt identification sensor; 26. Back-belt baffle; 27. Short belt slot for belt inlet; 28. Heterosexual connection steering belt slot; 29. ​​Pipe position strip;

[0046] 31. Middle clamping knife; 32. Welding head; 33. Tail clamping knife; 34. Head clamping knife; 35. Second connecting rod; 36. First connecting rod; 361. First meshing part; 362. First working part; 363. First spring connecting part; 364. Third rotating shaft; 37. Third connecting rod; 38. Second spring; 39. First spring; 310. Third spring; 311. Second cam; 312. Fourth cam; 313. First cam; 314. Fifth cam; 315. Third cam; 316. Fourth connecting rod; 3161. Fourth meshing part; 3162. Fourth working part; 3163. Fourth spring connecting part; 3164. Fourth rotating shaft; 317. Fifth connecting rod; 318. Fourth spring; 319. Fifth spring; 320. First baffle plate; 321. Second baffle plate; 322. Welding connecting rod; 323. Cutter; 324. Synchronous wheel assembly. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0048] The purpose of the present invention is to provide a packing head for a packing machine to solve the problems existing in the prior art. A high-tension driving pulley and a low-tension driving pulley are respectively provided with a first pressing wheel assembly and a second pressing wheel assembly. A first lever of the first pressing wheel assembly is pulled by a first tension spring to separate the first pressing wheel assembly from the high-tension driving pulley, so that the low-tension driving pulley can be not affected by the high-tension driving pulley during the process of conveying the packing belt, ensuring the fast and effective conveyance of the packing belt.

[0049] In order to make the above objects, features and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] As Figures 1 to 13 shown, the present invention provides a packing head for a packing machine, including a conveying and tensioning unit 1 and a connecting unit 3 mounted on a frame. Among them, the conveying and tensioning unit 1 is used for conveying the packing belt or tensioning the packing belt during the process of connecting the head and tail ends of the packing belt; the connecting unit 3 is used for pressing and welding the head and tail ends of the packing belt after the packing belt is conveyed in place. The connecting unit 3 includes a head clamping knife 34, a tail clamping knife 33 and a welding head 32. The head clamping knife 34 and the tail clamping knife 33 are respectively located on the moving track of the packing belt conveyed by the conveying and tensioning unit 1, and respectively clamp the head and tail of the packing belt. The welding head 32 is used for welding the overlapping part of the head and tail ends of the packing belt.

[0051] The conveying and tensioning unit 1 includes a high-tension driving pulley 11 and a low-tension driving pulley 12. Both the high-tension driving pulley 11 and the low-tension driving pulley 12 are connected with a power mechanism. The power mechanism can adopt the same driving motor or respectively correspond to driving motors. When adopting the same driving motor, a torque-changing mechanism such as a gear assembly can be used for torque change. The high-tension driving pulley 11 cooperates with the first pressing wheel assembly to form a first packing belt channel, and the packing belt is pressed by the high-tension driving pulley 11 and the first pressing wheel assembly in the first packing belt channel for conveying; the low-tension driving pulley 12 cooperates with the second pressing wheel assembly to form a second packing belt channel, and the packing belt is pressed by the low-tension driving pulley 12 and the second pressing wheel assembly in the second packing belt channel for conveying. The high-tension driving pulley 11 can provide high tension for the working condition of tightly tensioning the packing belt, and the low-tension driving pulley 12 can provide low tension for the working condition of low-tension tightening or fast conveying of the packing belt. The first pressing wheel assembly includes a first lever 13 and a driven wheel structure 14 and a guiding free wheel 15 respectively hinged to both ends of the first lever 13. Among them, a rotating support plate 115 can be arranged on the first lever 13. The rotating support plate 115 is installed on both sides of the first lever 13 and clamps the guiding free wheel 15 in the middle. A rotating shaft for the guiding free wheel 15 to rotate is arranged on the rotating support plate 115. The first lever 13 can rotate around its fulcrum (such as the first rotating shaft 16). When a force is applied to one end of the first lever 13, the other end rotates in the same direction around the fulcrum. The packing belt sequentially passes through the first packing belt channel, the second packing belt channel and adheres to the guiding free wheel 15 for belt receiving and sending. When the packing belt is tightened, a reverse thrust will be provided to the guiding free wheel 15. Under the action of this force, the first lever 13 will rotate around the fulcrum, and then be able to press the driven wheel structure 14 to press towards the high-tension driving pulley 11. Furthermore, the tighter the packing belt is wound, the greater this pressure is, so that sufficient clamping force for the packing belt can be provided during the tightening process of the packing belt to avoid the packing belt from slipping. When the packing belt is quickly conveyed or low-tension tightened, the low-tension driving pulley 12 and the second pressing wheel assembly jointly act to press the packing belt for conveying. At this time, the high-tension driving pulley 11 and the driven wheel structure 14 may cause a certain resistance to the conveying of the packing belt. For this reason, a first tension spring 17 is connected to the side of the first lever 13 close to the guiding free wheel 15. The first tension spring 17 is used to pull the first lever 13 to drive the driven wheel structure 14 away from the high-tension driving pulley 11. At this time, a certain gap is formed between the driven wheel structure 14 and the high-tension driving pulley 11, enabling the packing belt to pass through smoothly.The conveying and tensioning unit 1 of the present invention is provided with a high-tension driving pulley 11 and a low-tension driving pulley 12, which are respectively provided with a first pressing wheel assembly and a second pressing wheel assembly. The first lever 13 of the first pressing wheel assembly is pulled by a first tension spring 17 to separate the first pressing wheel assembly from the high-tension driving pulley 11, so that the low-tension driving pulley 12 can convey the packing belt without being affected by the high-tension driving pulley 11 during the conveying process, ensuring the fast and effective conveying of the packing belt.

[0052] Combined with Figure 4 As shown, the driven wheel structure 14 includes a connecting plate 141, a hinge shaft 143 and two driven pulleys 142 that are respectively rotatably connected to the connecting plate 141. The connecting plate 141 serves as a supporting structure for the hinge shaft 143 and the two driven pulleys 142, and can arrange the three in a triangular shape. Moreover, the hinge shaft 143 is located on the side of the two driven pulleys 142 away from the high-tension driving pulley 11. By controlling the position of the hinge shaft 143, the driven pulleys 142 can be pressed against the high-tension driving pulley 11, and a packing belt passage is formed between the wheel surfaces of the two driven pulleys 142 and the high-tension driving pulley 11. That is to say, by controlling the position of the hinge shaft 143, the packing belt can be pressed between the two driven pulleys 142 and the high-tension driving pulley 11. The two driven pulleys 142 and the high-tension driving pulley 11 are distributed in a staggered shape. When adjusting the position of the hinge shaft 143, the two driven pulleys 142 are tangent to the high-tension driving pulley 11 and are pressed as close as possible towards the center direction of the high-tension driving pulley 11, which can ensure the pressing state and avoid misalignment.

[0053] As Figures 2 to 3 As shown, the conveying and tensioning unit 1 may include a base plate 116. The high-tension driving pulley 11, the first pressing wheel assembly, the low-tension driving pulley 12 and the second pressing wheel assembly are all installed on the base plate 116. The base plate 116 serves as a bearing structure and can ensure the relative position relationship of each installed component.

[0054] The conveying and tensioning unit 1 may further include a high-tension support plate 18, which is arranged in parallel with the base plate 116, and both can be fixedly installed on the frame. The two ends of the high-tension driving pulley 11 are respectively rotatably installed on the high-tension support plate 18 and the base plate 116, and the installation can be carried out by setting bearings. By adding the high-tension support plate 18 and making it cooperate with the base plate 116, the two ends of the high-tension driving pulley 11 can be effectively supported, and the stable operation of the high-tension driving pulley 11 can be ensured during the process of the high-tension driving pulley 11 providing high tension to drive the packing belt to move.

[0055] On one side of the first lever 13 close to the driven wheel structure 14, a first rotating shaft 16 is provided. The first rotating shaft 16 is equivalent to the fulcrum of the first lever 13. The first lever 13 itself can rotate around the first rotating shaft 16, enabling the first lever 13 to play a role in torque amplification. The two end parts of the first rotating shaft 16 can be respectively rotatably installed on the high-tensile support plate 18 and the substrate 116, and the high-tensile support plate 18 and the substrate 116 are used to provide effective support to ensure the stable operation of the first lever 13 when rotating and applying force.

[0056] Combined with Figure 5 As shown, the second pressing wheel assembly can include a second lever 110. One end of the second lever 110 is hinged with a pressing wheel structure. The pressing wheel structure is used to press the packing belt against the low-tensile driving pulley 12. Through the setting of the second lever 110, a torque amplification effect can be provided, improving the pressing force of the pressing wheel structure relative to the low-tensile driving pulley 12, and thus avoiding the phenomenon of the packing belt slipping during the movement of the packing belt. The other end of the second lever 110 is connected with a second tension spring 113. On the side of the second lever 110 close to the pressing wheel structure, a second rotating shaft 111 is provided. Under the action of the second tension spring 113, the power for the second lever 110 to rotate around the second rotating shaft 111 can be provided, so as to use the second tension spring 113 to pull the second lever 110 to drive the pressing wheel structure to approach the low-tensile driving pulley 12.

[0057] One end of the second tension spring 113 is connected to the second lever 110, and the other end of the second tension spring 113 can be connected with a tension adjusting mechanism 114. The tension adjusting mechanism 114 includes a support installed on the substrate 116, a bolt passing through the support, and a nut threadedly connected to the bolt. The end of the bolt is connected to the second tension spring 113, and the second tension spring 113 and the nut are respectively located on both sides of the support. When the nut is rotated, since the nut abuts against the support, at this time, the bolt can move axially, and thus the stretching amount of the second tension spring 113 can be adjusted, and further the tension force applied by the second tension spring 113 to the second lever 110 can be adjusted, and finally the magnitude of the pressing force of the pressing wheel structure relative to the low-tensile driving pulley 12 can be realized.

[0058] The pressing wheel structure can include a U-shaped bracket 112. A pressing belt pulley 19 is rotatably arranged in the two arms of the U-shaped bracket 112. At the bottom of the U-shaped bracket 112, a second rotating shaft 111 parallel to the pressing belt pulley 19 is provided. The U-shaped bracket 112 can drive the pressing belt pulley 19 to rotate around the second rotating shaft 111, and thus adjust the magnitude of the pressure of the pressing belt pulley 19 pressing against the low-tensile driving pulley 12. The second rotating shaft 111 is installed on the substrate 116, and the substrate 116 is used to support the rotation of the second rotating shaft 111 and thus support the U-shaped bracket 112. A second packing belt channel is formed between the wheel surfaces of the pressing belt pulley 19 and the low-tensile driving pulley 12.

[0059] The second lever 110 can be L-shaped. The bottom side of the L-shaped second lever 110 is connected to the U-shaped bracket 112, and the bottom side is in the same extending direction as the arms of the U-shaped bracket 112. The vertical side of the L-shaped second lever 110 is connected to the second tension spring 113. At this time, the second tension spring 113 can also be located in the extending direction of the arms of the U-shaped bracket 112.

[0060] As Figure 1 shown, a welding motor 7 is installed on the frame, and the welding motor 7 is power-connected to the welding head 32. The welding motor 7 drives the driven eccentric shaft to rotate through the synchronous pulley assembly 324, and the welding connecting rod 322 swings, so as to drive the welding head 32 to perform friction welding relative to the packing belt.

[0061] The high-tensile driving pulley 11 can be connected to a high-tensile servo motor 5, and the low-tensile driving pulley 12 can be connected to a low-tensile servo motor 4. By separately controlling the individual high-tensile servo motor 5 and low-tensile servo motor 4, the output of high tension and low tension can be achieved. The mechanical structure is simple and it is convenient to realize automatic control. The high-tensile servo motor 5 and the low-tensile servo motor 4 can both be installed on the substrate 116, and then the substrate 116 is used to effectively support and fix the high-tensile driving pulley 11, the high-tensile servo motor 5, the low-tensile driving pulley 12 and the low-tensile servo motor 4.

[0062] As Figures 10 to 13As shown, the connecting unit 3 includes a cam-link structure and a first baffle 320 that respectively cooperates with the working structures (the head clamping knife 34, the tail clamping knife 33, and the welding head 32) at the working positions. The cam-link structure may include the same camshaft and several linkages axially spaced apart on the camshaft. By using the rotation of the cam, when the cam is in the advancing stroke, it can push the linkages to rotate. When the cam is in the return stroke, it relies on the pulling force of the spring. Different working structures are connected to different linkages. By rotating the camshaft to drive different cams to rotate, and by changing the meshing position between the cam and the linkage, and under the action of the spring, the drive of the linkage is realized, thereby changing the action state of the working structure and realizing different working processes. The so-called working position refers to the position where the working process is completed, and it controls the working structure to reach and leave the working position to complete the process of connecting the packing belt. The welding head 32 is used to weld the head and tail of the packing belt into a ring by means of a frictional action to complete the packing work of the object to be packed. The cam-link structure includes a first linkage 36, a first cam 313, and a first spring 39 connected to the same side of the rotating shaft on the first linkage 36. According to the positions of the first cam 313 and the first spring 39 connected to the first linkage 36, the action effects of the first cam 313 and the first spring 39 on the first linkage 36 (in the case of the same force application direction, making the first linkage 36 rotate around its rotating shaft) are the same. The end of the first linkage 36 is connected to the welding head 32. In order to realize the control of the welding head 32, the first cam 313 and the first spring 39 act in opposite directions on the rotation direction of the first linkage 36, that is, the first spring 39 can make the welding head 32 move towards the working position, so that the welding head 32 cooperates with the first baffle 320 to clamp and weld the head and tail ends of the overlapping packing belt together. After welding is completed, the first cam 313 can make the welding head 32 move away from the working position, release the clamping of the packing belt, so that the packing belt can be separated from the device, and the connection of the packing belt is completed. In the present invention, a welding head 32 for welding and connecting the packing belt is provided, and the welding head 32 is driven by a cam-link structure. The cam-link structure includes a first linkage 36, a first cam 313, and a first spring 39 connected to the same side of the rotating shaft on the first linkage 36.

[0063] As Figure 10As shown, in addition to being connected with the welding head 32, the end of the first connecting rod 36 can also be provided with a cutter 323 for cutting the packing belt. Here, the cutter 323 and the welding head 32 are pushed by a push block (middle clamping cutter 31) at the end of the first connecting rod 36 to cut and press the wireless end of the welding packing belt. The cutter 323, the welding head 32 and the push block (middle clamping cutter 31) are relatively independent units, so that they will not affect each other during the vibration friction process of the welding head 32. With the movement of the first connecting rod 36, the cutter 323 will reach the working position with the packing belt along with the welding head 32. While the welding head 32 completes the friction welding, the tail end (wireless end) of the packing belt will be cut off to form a loop of the packing belt, thus completing the process of connecting the packing belt.

[0064] The welding head 32 is installed on the middle clamping cutter 31. The middle clamping cutter 31 is hinged to the first connecting rod 36. The movement of the middle clamping cutter 31 will drive the movement of the welding head 32. At the same time, the welding head 32 is connected to the welding connecting rod 322. The welding connecting rod 322 is connected to the welding motor 7 through an eccentric shaft. The welding motor 7 drives the eccentric shaft and the welding connecting rod 322 to move, so as to drive the welding head 32 to perform friction welding relative to the packing belt. And because the welding head 32 is connected to both the middle clamping cutter 31 and the welding connecting rod 322, the welding head 32 can obtain a certain clamping force through the middle clamping cutter 31 and realize friction welding through the welding connecting rod 322, so as to ensure the welding effect.

[0065] The working structure can also include a tail clamping cutter 33, which is used to clamp the tail of the packing belt (i.e., the wireless end) to avoid the packing from loosening during the welding process, and further avoid the waste of the packing belt caused by unqualified packing quality due to packing loosening or the need for re-packing. The tail clamping cutter 33 can cooperate with the second connecting rod 35, the second cam 311 and the second spring 38 (similar to the cooperation mode with the welding head 32) to clamp the tail of the packing belt; after the welding is completed, the tail clamping cutter 33 moves away from the working position to release the clamping of the tail of the packing belt, so that the packing belt can be separated from the device.

[0066] The head clamping cutter 34 is used to clamp the head of the packing belt (i.e., the free end) to facilitate the reverse conveying of the packing belt for the tensioning operation, that is, after clamping the head of the packing belt, the tail of the packing belt (i.e., the wireless end) is pulled to be tensioned. The head clamping cutter 34 can cooperate with the third connecting rod 37, the third cam 315 and the third spring 310 (similar to the cooperation mode with the welding head 32) to clamp the head of the packing belt; after the welding is completed, the head clamping cutter 34 moves away from the working position to release the clamping of the head of the packing belt, so that the packing belt can be separated from the device.

[0067] Combined Figure 12As shown, the first link 36 includes a first engaging portion 361 that engages with the first cam 313; includes a first spring connection portion 363 connected to the end of the first spring 39. A spring fixing device is hinged to the first spring connection portion 363, and the spring fixing device can penetrate inside the first spring 39 and fix with the end of the first spring 39, so that the first spring 39 can apply a pulling force to the first link 36; includes a first working portion 362 connected to the middle clamping knife 31. The first working portion 362 is hinged to the middle clamping knife 31, so that the middle clamping knife 31 can move linearly to push the welding head 32 to act to clamp and weld the packing belt; further includes a third rotating shaft 364, and the third rotating shaft 364 is the rotating shaft of the first link 36, and it is arranged at the end of the first link 36 close to the end connected with the welding head 32 (middle clamping knife 31). At this time, both the force applied by the first spring 39 to the first link 36 through the first spring connection portion 363 and the force applied by the first cam 313 to the first link 36 through the first engaging portion 361 can utilize the lever principle to improve the acting force on the middle clamping knife 31 and the welding head 32, thereby improving the control ability for the middle clamping knife 31 and the welding head 32, and further improving the clamping, welding effect or reset effect. The second link 35 and the third link 37 can adopt the same structure as the first link 36, and both the second link 35 and the third link 37 can utilize the action of the lever principle to better control the tail clamping knife 33 and the head clamping knife 34.

[0068] As Figures 10 to 11 shown, the first link 36, the second link 35 and the third link 37 are all in a V-shaped structure. The vertices of each V-shaped structure are respectively provided with engaging portions that engage with the cams, and each engaging portion is respectively engaged and connected with the corresponding first cam 313, second cam 311 and third cam 315. An installation space can be formed inside the V-shaped structure, which is convenient for the installation of other components and structures.

[0069] As Figure 10As shown, the cam-connecting rod structure may further include a fourth connecting rod 316 and a fourth cam 312 and a fourth spring 318 connected to the same side of the rotating shaft of the fourth connecting rod 316. According to the position at which the fourth cam 312 and the fourth spring 318 are connected to the fourth connecting rod 316, the effects of the fourth cam 312 and the fourth spring 318 on the fourth connecting rod 316 (the direction in which the fourth connecting rod 316 rotates around its rotating shaft when the force directions are the same) are the same. The end of the fourth connecting rod 316 is connected to a first baffle 320. To achieve control over the first baffle 320, the fourth cam 312 and the fourth spring 318 have opposite effects on the rotation direction of the fourth connecting rod 316, that is, the fourth spring 318 can move the first baffle 320 toward the working position, so that the tail clamping knife 33, the middle clamping knife 31 (welding head 32) and the head clamping knife 34 cooperate with the first baffle 320 to clamp and weld the strapping tape; after welding is completed, the fourth cam 312 can move the first baffle 320 away from the working position, release the clamping of the strapping tape, and allow the strapping tape to detach from the device.

[0070] The connecting unit 3 may further include a second baffle 321 for limiting the position of the head (i.e., the free end) of the strapping tape. A boss is provided on the second baffle 321. When the second baffle 321 moves to the working position, the boss can form a barrier to the strapping tape penetration position, thereby preventing the head of the strapping tape from continuing to move, and ultimately forming a connection area where the head and tail of the strapping tape overlap. The cam-link structure may include a fifth link 317 and a fifth cam 314 and a fifth spring 319 connected to the same side of the rotating shaft of the fifth link 317. According to the position at which the fifth cam 314 and the fifth spring 319 are connected to the fifth link 317, the effects of the fifth cam 314 and the fifth spring 319 on the fifth link 317 (the direction in which the fifth link 317 rotates around its rotating shaft when the force directions are the same) are the same. A second baffle 321 is connected to the end of the fifth link 317. In order to control the second baffle 321, the fifth cam 314 and the fifth spring 319 have opposite effects on the rotation direction of the fifth link 317, that is, the fifth spring 319 can move the second baffle 321 to the working position, that is, the second baffle 321 can block the movement of the head of the strapping tape. Before formal welding, the second baffle 321 needs to be moved out of the working position, that is, the fifth cam 314 can move the second baffle 321 away from the working position to avoid affecting the welding process.

[0071] Combination Figure 13As shown in the figure, the fourth link 316 includes a fourth engaging portion 3161 that engages with the fourth cam 312; a fourth spring connecting portion 3163 that is connected to the end of the fourth spring 318. The fourth spring connecting portion 3163 is hinged with a spring fixing device, and the spring fixing device can be formed in the form of a hook to fix the end of the fourth spring 318, so that the fourth spring 318 can apply a pulling force to the fourth link 316; a fourth working portion 3162 that is connected to the first baffle 320. The fourth working portion 3162 is hingedly connected to the first baffle 320 to be able to push the first baffle 320 to complete a lateral movement, and can cooperate with the tail clamping knife 33, the middle clamping knife 31 (welding head 32) and the head clamping knife 34 at the working position to complete welding; it also includes a fourth rotating shaft 3164, and the fourth rotating shaft 3164 is the rotating shaft of the fourth link 316. The fifth link 317 can adopt the same structure as the fourth link 316, that is, the fifth link 317 includes a fifth engaging portion, a fifth working portion, a fifth spring connecting portion and a fifth rotating shaft. The fourth link 316 and the fifth link 317 can both be set in an L-shaped structure. The endpoints of the short sides of each L-shaped structure are respectively provided with engaging portions, and are meshed and connected with the corresponding fourth cam 312 and fifth cam 314 through the engaging portions. The vertices of each L-shaped structure are respectively provided with spring connecting portions, and are connected with the corresponding fourth spring 318 and fifth spring 319 through the spring connecting portions. By adopting the L-shaped structure setting method, on the one hand, an installation space for other components and structures can be formed inside the L-shaped structure, and on the other hand, the setting directions of the fourth link 316 and the fifth link 317 relative to other links can be converted, so as to facilitate the setting of each component and structure more conveniently, and further improve the structural compactness of the entire device.

[0072] The connecting unit 3 mainly consists of five links that perform five different linear motions driven by five corresponding cams (arranged on the same camshaft), respectively controlling the middle clamping knife 31 (welding head 32), the tail clamping knife 33, the head clamping knife 34, the first baffle 320 and the second baffle 321. Among them, the middle clamping knife 31 (welding head 32), the tail clamping knife 33 and the head clamping knife 34 require strong pressing force, and large link extension springs can be respectively arranged on the corresponding first link 36, second link 35 and third link 37, that is, the first spring 39, the second spring 38 and the third spring 310 all adopt large link extension springs. And the rotating shafts of each link are close to the corresponding working structures, thus forming a structure of a high-strength lever, so that the head, middle and tail of the joint of the packing belt can be effectively clamped, and the friction welding process can be completed at the same time. The linear motions of the first baffle 320 and the second baffle 321 do not require much force, so the corresponding fourth spring 318 and fifth spring 319 are small link extension springs, and the corresponding link rotating shafts can also be installed at the middle positions of the fourth link 316 and the fifth link 317.

[0073] As Figure 1As shown, the cam-link structure is dynamically connected to a position control motor 6. The position control motor 6 can control the rotation of each cam, accurately control the rotation position of the cam, and further control the action states of the components corresponding to the cam-link structure. Thus, the connection unit 3 of the present invention provides power for the welding head 32 by setting a welding motor 7, controls the position of the cam-link structure through the position control motor 6 to control the action states of the welding head 32, the head clamping knife 34, the tail clamping knife 33, the middle clamping knife 31, etc., provides a low tension for the conveying or tensioning of the packing tape by setting a low-tension servo motor 4, and provides a high tension for the tensioning of the packing tape by setting a high-tension servo motor 5. In short, by controlling the operation of different structures or components in the packing head through different motors, the system structure can be simplified and the level of automatic control can be improved.

[0074] As Figures 6 to 9 shown, a tape groove assembly 2 is provided at the tape output end of the guiding free wheel 15. The tape groove assembly 2 may include an L-shaped base 21, L-shaped baffles 22 on both sides of the L-shaped base 21, and a tape return baffle 26 outside the L-shaped base 21. At this time, the L-shaped base 21, the L-shaped baffles 22, and the tape return baffle 26 enclose a channel for conveying the packing tape. Specifically, the inner side (i.e., the side facing the small angle clamped by the two arms of the L-shaped base 21) and the outer side (i.e., the side facing the large angle clamped by the two arms of the L-shaped base 21) of the L-shaped base 21 respectively form a tape feeding channel and a tape return channel. The packing tape output from the conveying and tensioning unit 1 passes out along the tape feeding channel, winds around the goods and then returns into the tape return channel, and then the packing tape continues to move forward, forming a packing tape overlapping section at the intersection of the extension lines of the tape feeding channel and the tape return channel. A connection unit 3 is provided at the overlapping section, and the packing tape is pressed and welded through structures such as the head clamping knife 34, the tail clamping knife 33, the welding head 32, and the middle clamping knife 31 of the connection unit 3.

[0075] A tube positioning strip 29 may be provided at the entrance of the tape feeding channel. The tube positioning strip 29 can be installed on the L-shaped baffle 22 so that the passing packing tape is located between the tube positioning strip 29 and the L-shaped base 21, and the tube positioning strip 29 is used to restrict the conveying path of the packing tape to avoid the situation that the packing tape warps in the tape feeding channel and hooks other structures to affect the conveying. A turning bottom tape head 23 is provided at the exit of the tape feeding channel, and a turning top tape head 24 is provided at the exit of the tape return channel. The turning bottom tape head 23 is a block structure, and U-shaped groove structures are respectively provided on both sides of the turning top tape head 24. A channel for the packing tape to output from the tape feeding channel to the tape groove assembly 2 can be formed between the turning bottom tape head 23 and the turning top tape head 24, and a channel for the packing tape to output from the tape return channel to the tape groove assembly 2 can be formed between the turning top tape head 24 and the tape return baffle 26.

[0076] Combined with Figure 8As shown, at the tape inlet end of the first packing tape channel, there is a short tape inlet slot 27. The short tape inlet slot 27 is located in the front position between the driven wheel structure 14 and the high-tensile driving pulley 11. The short tape inlet slot 27 is provided with an arc-shaped pointed nozzle facing the first packing tape channel, which can restrict the packing tape in all directions and make it only convey in the direction of the first packing tape channel.

[0077] Combined with Figure 9 As shown, at the tape inlet end of the second packing tape channel, there is a special-shaped connecting and turning tape slot 28. The special-shaped connecting and turning tape slot 28 is located on the path between the high-tensile driving pulley 11 and the low-tensile driving pulley 12. The special-shaped connecting and turning tape slot 28 is used to connect the first packing tape channel and the second packing tape channel, and can enable the packing tape to smoothly enter the pressing position of the second pressing wheel assembly after passing through the pressing position of the first pressing wheel assembly.

[0078] At the inlet of the tape return channel, a tape presence sensor 25 can also be provided. The tape presence sensor 25 can be a distance sensor, which can detect when a packing tape penetrates into the tape return channel and send a signal to the control device. It can also be a position sensor. When a packing tape touches the contact piece and makes it fit the position sensor, the position sensor can send a signal to the control device.

[0079] In the present invention, specific examples are used to illustrate the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A packing head for a packing machine, characterized in that: It includes a conveying and tensioning unit and a connecting unit installed on a frame; The connecting unit includes a head clamping knife, a tail clamping knife and a welding head. The head clamping knife and the tail clamping knife are respectively located on the moving track of the packing belt conveyed by the conveying and tensioning unit, and respectively clamp the head and the tail of the packing belt. The welding head is used for welding the overlapping part of the head and the tail of the packing belt; The conveying and tensioning unit includes a high-tension driving pulley, a first pressing wheel assembly that cooperates with the high-tension driving pulley to form a first packing belt channel, a low-tension driving pulley, and a second pressing wheel assembly that cooperates with the low-tension driving pulley to form a second packing belt channel. The first pressing wheel assembly includes a first lever and a driven wheel structure and a guiding free wheel respectively hinged at both ends of the first lever. The packing belt sequentially passes through the first packing belt channel, the second packing belt channel and fits the guiding free wheel for belt feeding and taking in; A rotating support plate is arranged on the first lever, and the rotating support plate is installed on both sides of the first lever; When the packing belt is tightened, it will provide a reverse thrust to the guiding free wheel. Under the action of the reverse thrust, the first lever will rotate around the fulcrum, and then can press the driven wheel structure to press towards the high-tension driving pulley direction to prevent the packing belt from slipping; When the packing belt is conveyed quickly or tensioned with low tension, the low-tension driving pulley and the second pressing wheel assembly act together to press the packing belt for conveying. A first tension spring is connected to one side of the first lever close to the guiding free wheel. The first tension spring is used to pull the first lever to drive the driven wheel structure away from the high-tension driving pulley, so that there is a certain gap between the driven wheel structure and the high-tension driving pulley, which can enable the packing belt to pass smoothly; The second pressing wheel assembly includes a second lever. One end of the second lever is hinged with a pressing wheel structure. The other end of the second lever is connected with a second tension spring. A second rotating shaft is arranged on one side of the second lever close to the pressing wheel structure. The second tension spring is used to pull the second lever to drive the pressing wheel structure close to the low-tension driving pulley.

2. The packing head for a packing machine according to claim 1, characterized in that: A welding motor is installed on the frame, and the welding motor is power-connected to the welding head.

3. The packing head for a packing machine according to claim 2, characterized in that: The high-tension driving pulley is connected with a high-tension servo motor, and the low-tension driving pulley is connected with a low-tension servo motor. The high-tension servo motor and the low-tension servo motor are both installed on the frame.

4. The packing head for a packing machine according to claim 3, characterized in that: The connecting unit includes a cam-link structure and a first baffle that respectively cooperate with the head clamping knife, the tail clamping knife and the welding head in the working position; The cam-link structure includes a link and a cam and a spring connected to the same side of the rotating shaft on the link. The cam and the spring act in opposite directions on the rotating direction of the link. The end of the link is connected with an operating structure. The spring can make the operating structure move towards the working position, and the cam can make the operating structure move away from the working position; The link includes a first link, a second link and a third link. The cam includes a first cam, a second cam and a third cam. The spring includes a first spring, a second spring and a third spring. The operating structure includes a welding head, a tail clamping knife and a head clamping knife.

5. The packing head for a packing machine according to claim 4, wherein: The cam-link structure is dynamically connected to a position control motor.

6. The packing head for a packing machine according to any one of claims 1-5, characterized in that: A tape groove assembly is provided at the tape-out end of the guiding free wheel. The tape groove assembly includes an L-shaped base, L-shaped baffles on both sides of the L-shaped base, and a tape-return baffle outside the L-shaped base. A tape-feeding channel and a tape-return channel are respectively formed inside and outside the L-shaped base, and a packing tape overlapping section is formed at the intersection of the extension lines of the tape-feeding channel and the tape-return channel.

7. The packing head for a packing machine according to claim 6, characterized in that: A tube positioning strip is provided at the entrance of the tape-feeding channel. The packing tape is located between the tube positioning strip and the L-shaped base. A turning bottom tape head is provided at the exit of the tape-feeding channel, and a turning top tape head is provided at the exit of the tape-return channel.

8. The packing head for a packing machine according to claim 7, characterized in that: An inlet short tape groove is provided at the tape-in end of the first packing tape channel. The inlet short tape groove is provided with an arc-shaped pointed nozzle facing the first packing tape channel.

9. The packing head for a packing machine according to claim 8, characterized in that: A special-shaped connection turning tape groove is provided at the tape-in end of the second packing tape channel. The special-shaped connection turning tape groove is used to connect the first packing tape channel and the second packing tape channel.

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