Progressive punch

A strapping tool for forming a seal between two portions of strapping material, comprising:

• a jaw assembly;
• a fixed support carried by the jaw assembly;
• a movable support carried by the jaw assembly;
• an actuating lever operably connected to the movable support for moving the movable support toward and away from the fixed support in a direction of movement for engaging the strapping material;
• a fixed punch formed as a unitary element carried by the fixed support;
• a movable punch formed as a unitary element carried by the movable support for movement toward and away from the fixed punch,
• both the fixed punch and the movable punch including first and second punching heads including cutting edges with arcuate profiles integrally and fixedly attached to one another, each of the first punching heads having a height defined by a distance between a respective outermost peripheral point of the first punching head and a plane perpendicular to the direction of movement, and each of the second punching heads having a height defined by a distance between a respective outermost peripheral point of the second punching heads and a plane perpendicular to the direction of movement, wherein the heights of the first punching heads are different from the heights of the second punching heads, and wherein the punching heads progressively engage the strap material with the first punching heads initially engaging the strapping material at a different time than the second punching heads initially engage the strapping material.

A jaw assembly for use in a strapping tool for forming a seal between two portions of strapping material, the jaw assembly comprising:

• a fixed support;
• a movable support;
• an actuating lever operably connected to the movable support for moving the movable support toward and away from the fixed support in a direction of movement for engaging the strapping material;
• a fixed punch formed as a unitary element carried by the fixed support;
• a movable punch formed as a unitary element carried by the movable support for movement toward and away from the fixed punch,
• both the fixed punch and the movable punch including first and second punching heads including cutting edges with arcuate profiles integrally and fixedly attached to one another, each of the first punching heads having a height defined by a distance between a respective outermost peripheral point of the first punching head and a plane perpendicular to the direction of movement, and each of the second punching heads having a height defined by a distance between a respective outermost peripheral point of the second punching heads and the plane perpendicular to the direction of movement, wherein the heights of the first punching heads are different from the heights of the second punching heads, and wherein the punching heads progressively engage the strap material, with the first punching heads initially engaging the strapping material at a different time than the second punching heads initially engage the strapping material.