Carton bottom sealer apparatus and method

1. A method for effecting closure of an open end of a carton blank by placing pressure-sealable bottom end closure panels of the carton blank into overlying relationship to one another and pressure sealing the overlying bottom end closure panels using a bottom sealing apparatus, the method comprising:

mechanically linking a cam and a pressure pad using there between a cam lever and an air spring, the cam lever converting rotating motion of the cam into linear motion defining a first stroke distance, the pressure pad capable of being moved in response to input provided by the cam defining a second stroke distance; and

absorbing a portion of the first stroke distance using the air spring.

2. The method of claim 1 , wherein the air spring comprises an air cylinder.

3. The method of claim 2 further comprising forcibly extending a cylinder rod of the air cylinder to absorb the portion of the first stroke distance with the air cylinder in a retracted configuration.

4. The method of claim 2 further comprising actuating the air cylinder and decoupling the cam and the pressure pad such that the pressure pad remains in a retracted position irrespective of rotation of the cam.

5. The method of claim 4 wherein the step of actuating the air cylinder includes extending the air cylinder by providing communication between the air cylinder and a pressurized air source.

6. The method of claim 5 further comprising regulating the air pressure of the pressurized air source using a pressure regulator.

7. The method of claim 1 further comprising sealing an open end of a carton blank by applying pressure to overlying portions of the carton blank using the pressure pad with the pressure pad in an extended position.

8. An apparatus for effecting closure of an open end of a carton blank by placing pressure-sealable bottom end closure panels of the carton blank into overlying relationship to one another and pressure sealing the bottom end closure panels, the apparatus comprising:

a cam that rotates about an axis of rotation;

a cam lever operatively connected to the cam, the cam lever used to convert rotating motion of the cam into linear motion to define a first stroke distance;

a pressure pad mounted for movement toward and away from the bottom end closure panels to apply and release pressure on the overlying bottom end closure panels of the carton blank, the pressure pad capable of being moved in response to input provided by the cam to define a second stroke distance; and

an air spring mechanically linked between the cam lever and the pressure pad such that the air spring absorbs a portion of the first stroke distance.

9. The apparatus of claim 8 , wherein the air spring comprises an air cylinder.

10. The apparatus of claim 9 further comprising a control system for extending and retracting the air cylinder, the air cylinder being linked to the pressure pad such that the pressure pad moves in response to input provided by the cam lever with the air cylinder in one of a retracted or extended configuration and the pressure pad remains in a retracted position irrespective of movement of the cam with the cylinder in the other of the retracted or extended configuration.

11. The apparatus of claim 10 further comprising a surge tank capable of communicating with the air cylinder.

12. The apparatus of claim 11 further comprising a control valve for selectively allowing communication between the surge tank and the air cylinder.

13. The apparatus of claim 12 further comprising a pressure regulator for regulating pressure in the surge tank.

14. The apparatus of claim 10 , wherein the air cylinder absorbs the portion of the first stroke distance through forced extension of a cylinder rod of the air cylinder with the air cylinder in the retracted configuration.

15. The apparatus of claim 8 , wherein the cam is an open-face or closed-face cam, the cam lever including a roller that rides a surface of the cam.

16. An apparatus for effecting closure of an open end of a carton blank by placing pressure-sealable bottom end closure panels of the carton blank into overlying relationship to one another and pressure sealing the overlying bottom end closure panels, the apparatus comprising:

a cam that rotates about an axis of rotation;

a cam lever operatively connected to the cam, the cam lever used to convert rotating motion of the cam into linear motion;

a pressure pad mounted for movement toward and away from the bottom end closure panels to apply and release pressure on the overlying bottom end closure panels of the carton blank, the pressure pad capable of being moved in response to input provided by the cam for a carton sealing operation; and

an air cylinder mechanically linked between the cam lever and the pressure pad,

wherein actuation of the air cylinder decouples the pressure pad and the cam such that the pressure pad remains in a retracted position irrespective of movement of the cam.

17. The apparatus of claim 16 , wherein the air cylinder decouples the pressure pad and the cam with the air cylinder in an extended configuration.

18. The apparatus of claim 17 , wherein the air cylinder couples the pressure pad and the cam with the air cylinder in a retracted configuration such that the pressure pad is moved in response to input provided by the cam.

19. The apparatus of claim 16 , wherein the cam is an open-face or closed-face cam, the cam lever including a roller that rides a surface of the cam.

20. The apparatus of claim 16 further comprising a surge tank capable of communicating with the air cylinder.

21. The apparatus of claim 20 further comprising a control valve for selectively allowing communication between the surge tank and the air cylinder.

22. The apparatus of claim 21 further comprising a pressure regulator for regulating pressure in the surge tank.