TOOL OPERATED WITH LEVEL FOR WELDING STRIP AND METHOD FOR THIS CROSS REFERENCE WITH REQUESTS:; RELATED The present request is related to the Application .¡.E.U. No. 09 / 054,715 copendiente, entitled "Tool for Welding Strapping with Plate
Basis for Reducing the Strength of the Column of the Strapping and Method for This ", presented concurrently and commonly assigned in this document. BACKGROUND OF THE INVENTION! The invention relates generally to tools for clamping, and more particularly to tools for welding plastic straps usable in combination with strap tensioning tools -1 and methods for this.In packaging loading operations, it is generally known as welding the overlapping portions of plastic strip tensioned around the load U.S. Patent No. 3,564,033, issued April 4, 1972, entitled "Strapping Strain and Sealing Tool" and commonly assigned in this document, for example, discloses a pneumatically operated strapping tool 11 which forms a frictional fusion joint, or weld, by vibrating the contact surfaces of the
I gag welding the overlapping portions of the
during welding. The driven ram also,? moves the vibrating clamp within the friction coupling with the overlapping portions of the strip. While the vibrating clamp moves towards the overlapping portions of the strip, an edge; Shearing separates the upper strip and the 1 overlapping strip portions are subsequently welded together. After this, the Strapping is maintained, also commonly assigned in this document and as a reference, reveals a tool for strapping that has a pneumatic circuit to automatically control the operation of the tool, including the time and duration of the strip welding and the cooling period. # A pneumatically driven ram after the strip tension pivots a cam that moves a vibrating plate to weld in contact with the overlapping portions of strip to form The vibration of the welding plate ends after a period controlled by the accumulation of air in a chamber, from which the air purged from a cylinder I counter-pivots the cam to move the plate. weld away from the welded strip portions I after a cooling period of the tools many components the size and weight of the tool, and Increase costs related to manufacturing, operation and maintenance. the tool. The tool of !! US Patent No. 1 3,564,033, for example, requires a pneumatically operated ram for
The tool's operations are relatively inaccurate, producing as a strip tension and a result in inconsistent welding. The prior technology of the strapping tools, including those discussed above, also generally have a slack in the tension plate after their removal, particularly in applications where the load is relatively small or with irregular shapes. The loss of tension in the strip generally depends on the size of the base portion in the size of the load, and in many cases results in a strip with an inadequate tension. The present invention is generally directed towards advances in the technology of the strapping tools, and more particularly towards the strapping tools for forming frictional melted joints, or solders, through -i causing the vibrating surfaces to come into contact with one another: | interfacial of the overlapping portions of the strip, especially the plastic portions of the strip. I One of; The objects of the invention is to provide innovative problems in welding of innovative strapping which are tools for flexing pneumatically operated to control various operations of the tool and esp with rotating members by an invention the strapping for innovative strapping and methods for this having a cam for moving a rail gripper support member for engaging and retaining the strap arranged between these, a second cam member to enable a vibrator motor to vibrate a threaded cushion for '! weld, and a third cam member to move the threaded cushion to weld to a second support member for! attach and weld the overlapping portions of the strap. It is another object of the invention that of particularly a tensioned strap around loads
invention to provide tools of l | welding for the strip and methods for this that comprise base plates having the first member, 1! of support on a portion of the inlet end thereof, the second support member on a second portion thereof, and a third support member 1 cooperating with a movable tension rail gripper for coupling and retaining a portion of the free end. of the strip during the tension of the strip in a portion i of the drag end of the base plate, the second portion of the base plate is intermediate and entrainment portions of the downwardly declining I removed from the second portion. It is also another object of the invention to provide innovative welding tools for strapping and methods for this which reduce the strength of the column of a portion of the strap engageable through the vibrating threaded cushion for welding by deforming the portion of the strap, and more
to the mentioned one of the -free e 3 d between them. The
of the strip are welded together as will be discussed later, i In one exemplified embodiment, only feed ion of the strip 3 is between the feed wheel 20 and the foot member 22, and the foot member 22, it has a relatively smooth surface 23 for., 1! to allow a sliding movement of the portion i i fed from the strap 3 between them during the tension i. In an alternative embodiment, the free portion of the end of the strap 2 and the fed portion 1 of the strap 3 are both disposed between the feed wheel 20 and the foot member 22, and foot member 22 has a surface 23 for engaging and retaining the feed 20, as discussed above
Figure 1 illustrates the sealing rail gripper 30 polarized away from the first support member 32 through a compressed spring member 34 or other known means. The tool 100 also includes if a vibrating weld threaded cushion 40 moving towards uri, second weld support member 42 The threaded weld pad 40 is similarly polarized away from the second support member 42. «« A vibrating motor 50 is powered I to vibrate the threaded joint of welding 40, and 1! preferably the vibrator motor 50 is a pneumatically operated air II motor. A first cam member 60 is operated to move the sealing rail gripper 30 against its polarization to fit between them. operated to vibrate example when operating a pneumatic valve or switch. A third cam member 64 is operated to move the threaded hub for welding 40 against its polarization and toward the second support member 42 i for coupling and > welding the overlapping portions of strapping arranged between them. Figures 2a, 2b and 2c illustrate an example, 1 of cam assembly configuration in the first, second and third cam member 60, 62, 64 each 'I has its corresponding lobes and depressions to control with precision the activation and timing of the sealing rail gripper 30, the vibration motor 50, and the threaded threading pad 40 controlled in this manner without the rams being actuated; by inaccurately controllable air cylinders of the prior art technology; e • i a first roller member 36 rotating about an axis 37 coupled to an upper portion 38 of a seal rail gripper 40. A second roller member 46 is similarly rotated about an axis
47 coupled to 1 a top portion 48 of the cushion! threaded for welding 40. The first and the second roller member 36 and 46 are coupled through a first and a third cam member 60 and 64,! respectively _ to precisely drive the sealing rail gripper 30 and the threaded cushion for welding 40. The first and second roller members i i 36 and 46 also minimize mechanical wear and extend the life, operation of the tool. :! Figure 3 is a flow diagram 200 of support 42, to apply pressure on the >The welded portions of the strip during a cooling period after the vibrator motor 50 is disabled in a cooling step 240. The use and wear of the vibrator motor 50 is minimized when the motor is operated. 50 vibrator motor only when it is required for welding, thus extending the life of the same.:; The threaded cushion for welding 40 is the termination of the cooling period. Figures 1 and 3 illustrate the first cam member, the second cam member and the third cam member 60, 62, and 64 preferably • I rotatably supported on a common drive shaft 66 to form a rotary cam assembly. 'driven by a cam drive motor 60 coupled to a common drive shaft. Rotatingly supporting the first cam member, second member • i, cam member and third cam member 60, 62 and 64 with a common drive shaft 66 that controls in precise accurate manner the actuation of the sealing rail gripper, the drive of the jj Threaded cushion, for welding and the cooling period, without the inconsistencies and variations inherent in welding operations
of welding after tension. The welding operations I, or steps performed by the cam members 60, 62 and 64, as generally illustrated in FIG. Figure 3, they proceed automatically in a sequence
cutting the upper portion of the strip, more particularly cutting the fed portion of the strip finally engaged by the threaded cushion for vibrating weld, 40, while the vibrating threaded cushion 40 is moved to the second support member 42, but before welding the overlapping portions of strip. The flow diagram i of Figure 3 illustrates a breaking or cutting step of the strip 225 which occurs after the vibration step 220 and before the welding step 230. The cutting of the upper portion of the strip has the advantage of allowing that the upper portion of the strap strip of the overlapping portions of the strip before welding, and particularly the portion of the strap coupled by the vibrating thread bearing pad i 40. The relatively close space of the sealing rail gripper 30 and the threaded cushion for welding 40 cause the overlapping portions of the strip to be relatively rigid and inflexible, thus interfering with, or obstructing, the vibration of this by the vibrating thread cushion 40 which is vibrating. This is especially true when the distance between the sealant rail gripper 30 and the threaded cushion stops! welding 40 is less than about 5 cm (2 inches), as shown in the exemplified embodiment where the base plate 100 of the tool 100 has a relatively supportive dimension. The strength of the column is reduced to > \ fold the overlapping portions of the strip over the || vertex 120. A gap is preferably formed "i between the upper portion of the strap and the lower portion 1 of the strap 2 of the overlapping portions of the strap to further reduce the stiffness or strength of the column of the upper portion of the strap. , and I allow a greater degree of freedom of vibration under the vibratory action of the threaded pad for welding 40 to ensure a more resistant uniform welding. 1 Since the above written description of the invention enables one of the ordinary skills in the art of making and using what is in the present considered the best modality of the invention, and those ordinarily qualified will appreciate and .1 1 understand the existence of variations, combinations, modifications and equivalents. inside =? of the spirit and -'ability of the embodiments
embodiment within the scope of the appended claims.