Internal combustion fastener driving tool accelerator plate

• US 6,260,519 B1
• Filed: 07/13/1998
• Issued: 07/17/2001
• Est. Priority Date: 12/31/1997
• Status: Expired due to Fees

• Current Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: Porter-Cable Corporation (Stanley Black & Decker, Inc.)
• Inventors: Phillips, Alan
• Primary Examiner(s): Kamen, Noah P.
• Assistant Examiner(s): HUYNH, HAI H
• Application Number:
  US09/114,862
• Time in Patent Office: 1,100 Days
• Field of Search: 123/46.R, 123/46.SC, 60/397.6, 606/32, 606/33, 606/37, 227/9, 227/10
• US Class Current: 123/46.00R
• CPC Class Codes: B25C 1/005 for rows of contiguous nails
• CPC Class Codes: B25C 1/08 operated by combustion pressure

Abstract

The present invention relates to an accelerator plate that divides the combustion chamber of an internal combustion fastener driving tool.

Claims

1. A fastener driving tool operable through an internal combustion driven piston, the tool comprising:

a. a driver body comprising a piston housing, a piston slidably housed in the piston housing, a driving member coupled to the piston;

a combustion chamber defined by the body, piston housing, and piston;

the piston and driving member being arranged and configured to drive a fastener upon combustion of a metered amount of gaseous fuel in the combustion chamber;

b. the piston housing comprising an accelerator plate;

the accelerator plate being arranged and configured to divide the combustion chamber into a primary region and a secondary region and to direct ignited combustion gasses from the primary region into the secondary region of the combustion chamber;

c. the accelerator plate comprising a plate oriented to fill a cross-section of the piston housing generally perpendicular to an axis of the piston housing;

the accelerator plate defining only two concentric arrays of orifices, an inner array and an outer array the outer array of orifices comprising a plurality of outer orifices proximal to the piston housing and the inner array of orifices comprising a plurality of inner orifices in a region of the plate spaced from the center of the accelerator plate and spaced from the piston housing.

2. The fastener driving tool of claim 1, wherein the accelerator plate comprises a disk radially oriented within the piston housing.

3. The fastener driving tool of claim 1, wherein the inner orifices are dimensioned to, upon combustion of a metered amount of gaseous fuel in the combustion chamber, provide adequate pressure in the primary region of the combustion chamber for injecting flame under pressure into the secondary region of the combustion chamber and to provide adequate orifice surface area for injecting sufficient flame for combusting at an effective rate gaseous fuel in the secondary region of the combustion chamber.

4. The fastener driving tool of claim 1, wherein the inner orifices are in a region of the plate spaced from the center of the plate and from the piston housing are about half way between the center of the plate and a circle defined by the outer orifices.

5. The fastener driving tool of claim 1, wherein the accelerator plate further comprises a slot.

6. The fastener driving tool of claim 5, wherein the slot in the accelerator plate is radially oriented, intersects an outer edge of the accelerator plate, and has a length less than or equal to a radius of the accelerator plate.

7. The fastener driving tool of claim 5, wherein the accelerator plate slot is arranged and configured to receive a fuel metering tube.

8. The fastener driving tool of claim 7, further comprising a fuel metering tube, the fuel metering tube being received in the accelerator plate slot and being arranged and configured to dispense a first portion of the metered amount of fuel into the primary region of the combustion chamber and to dispense a second portion of fuel into the secondary region of the combustion chamber.

9. The fastener driving tool of claim 8, wherein the fuel metering tube comprises a port in the primary region of the combustion chamber that directs fuel at a 45°

angle to the accelerator plate.

10. The fastener driving tool of claim 8, wherein the first portion of fuel comprises about ⅓

of the total fuel and the second portion of the fuel comprises about ⅔

of the total amount of the fuel.

11. The fastener driving tool of claim 8, wherein the tool further comprises a port defined by the tool for receiving gaseous fuel and a shuttle valve;

the shuttle valve comprising a metering chamber housing, a metering chamber defined by the metering chamber housing, a combustion check valve, and one gating valve;

the metering chamber and gating valve being arranged and configured to provide asynchronous fluid communication between the metering chamber and the combustion chamber or between the metering chamber and the port defined by the tool for receiving gaseous fuel;

the combustion check valve being arranged and configured for preventing fluid flow from the combustion chamber to the metering chamber;

the fuel metering tube being in fluid communication with the shuttle valve.

12. The fastener driving tool of claim 11, wherein the fuel metering tube is coupled to the shuttle valve and penetrates a side of the piston housing.

13. The fastener driving tool of claim 11, wherein the shuttle valve further comprises a shuttle valve housing, the shuttle valve housing comprising the metering chamber housing, housing the combustion check valve and the gating valve, and defining an outlet, the outlet being in fluid communication with the metering tube.

14. The fastener driving tool of claim 1, wherein the accelerator plate further comprises an electrode.

15. The fastener driving tool of claim 14, wherein the electrode comprises an axially oriented pin substantially centrally located on the accelerator plate.

16. The fastener driving tool of claim 14, wherein the tool further comprises a spark plug and the electrode is oriented toward the spark plug and forms a spark gap.

17. The fastener driving tool of claim 16, the tool further comprising a piezoelectric device and a trigger;

the trigger being coupled to the piezoelectric device and arranged and configured to activate the piezoelectric device;

the piezoelectric device being arranged and configured to provide current to the spark plug upon activation by the trigger;

the spark plug being arranged and configured to initiate combustion of fuel and air in the combustion chamber.

18. A fastener driving tool operable through an internal combustion driven piston, the tool comprising:

a. a driver body comprising a piston housing, a piston slidably housed in the piston housing, a driving member coupled to the piston;

a combustion chamber defined by the body, piston housing, and piston;

the piston and driving member being arranged and configured to drive a fastener upon combustion of a metered amount of gaseous fuel within the combustion chamber;

the piston housing comprising an aluminum alloy;

the piston comprising a self-lubricating compression ring;

b. the piston housing comprising an accelerator plate;

the accelerator plate comprising a plate oriented to fill a cross-section of the piston housing generally perpendicular to an axis of the piston housing;

the accelerator plate defining a plurality of outer orifices proximal to the piston housing and a plurality of inner orifices in a region of the plate spaced from the center of the accelerator plate and spaced from the piston housing;

the accelerator plate being arranged and configured to divide the combustion chamber into a primary region and a secondary region and to provide fluid communication between the primary and secondary regions;

c. a pump system;

the pump system comprising an intake system, an exhaust system, a pump sleeve, a pump housing, the piston housing and a decompression port defined by the piston housing;

the pump sleeve sealably contacting the piston housing and defining a space around the piston housing;

the pump housing being arranged and configured to move axially in the space and to sealably contact the pump sleeve;

a compression spring in the space axially biasing the pump housing;

the intake system comprising a reed valve and being arranged and configured for fluid communication with the combustion chamber and surroundings of the tool;

the exhaust system being arranged and configured for fluid communication with the space and surroundings of the tool;

the decompression port being arranged and configured to relieve pressure in the combustion chamber as the pump housing is compressed into the space;

d. a fuel metering system comprising a port defined by the tool for receiving gaseous fuel, a regulator, and a shuttle valve in fluid communication with the port;

e. the shuttle valve comprising a metering chamber housing, a metering chamber defined by the metering chamber housing and a gating valve;

the metering chamber and gating valve being arranged and configured to provide asynchronous fluid communication between the metering chamber and the combustion chamber or between the metering chamber and the port;

the combustion check valve arranged and configured for preventing fluid flow from the combustion chamber to the metering chamber; and

f. a linear cam system arranged and configured to actuate the gating valve for fluid communication between the port for fuel and the combustion chamber upon compression of the pump housing into the space.

19. A fastener driving tool operable through an internal combustion driven piston, the tool comprising:

a. a driver body comprising a piston housing, a piston slidably housed in the piston housing, a driving member coupled to the piston;

a combustion chamber defined by the body, piston housing, and piston;

the piston and driving member being arranged and configured to drive a fastener upon combustion of a metered amount of gaseous fuel in the combustion chamber;

b. the piston housing comprising only one accelerator plate;

the accelerator plate being arranged and configured to divide the combustion chamber into a primary region and a secondary region and to direct ignited combustion gasses from the primary region into the secondary region of the combustion chamber;

c. the accelerator plate comprising a plate oriented to fill a cross-section of the piston housing generally perpendicular to an axis of the piston housing;

the accelerator plate defining a plurality of outer orifices proximal to the piston housing and a plurality of inner orifices in a region of the plate spaced from the center of the accelerator plate and spaced from the piston housing.

20. The fastener driving tool of claim 19, wherein the accelerator plate comprises a disk radially oriented within the piston housing.

21. The fastener driving tool of claim 19, wherein the inner orifices are dimensioned to, upon combustion of a metered amount of gaseous fuel in the combustion chamber, provide adequate pressure in the primary region of the combustion chamber for injecting flame under pressure into the secondary region of the combustion chamber and to provide adequate orifice surface area for injecting sufficient flame for combusting at an effective rate gaseous fuel in the secondary region of the combustion chamber.

22. The fastener driving tool of claim 19, wherein the inner orifices are in a region of the plate spaced from the center of the plate and from the piston housing are about half way between the center of the plate and a circle defined by the outer orifices.

23. The fastener driving tool of claim 19, wherein the accelerator plate further comprises a slot.

24. The fastener driving tool of claim 23, wherein the slot in the accelerator plate is radially oriented, intersects an outer edge of the accelerator plate, and has a length less than or equal to a radius of the accelerator plate.

25. The fastener driving tool of claim 23, wherein the accelerator plate slot is arranged and configured to receive a fuel metering tube.

26. A fastener driving tool operable through an internal combustion driven piston, the tool comprising:

a. a driver body comprising a piston housing, a piston slidably housed in the piston housing, a driving member coupled to the piston;

a combustion chamber defined by the body, piston housing, and piston;

the piston and driving member being arranged and configured to drive a fastener upon combustion of a metered amount of gaseous fuel in the combustion chamber;

b. the piston housing comprising an accelerator plate;

the accelerator plate being arranged and configured to divide the combustion chamber into a primary region and a secondary region and to direct ignited combustion gasses from the primary region into the secondary region of the combustion chamber;

c. the accelerator plate comprising a plate oriented to fill a cross-section of the piston housing generally perpendicular to an axis of the piston housing;

the accelerator plate defining a plurality of outer orifices proximal to the piston housing and a plurality of inner orifices in a region of the plate spaced from the center of the accelerator plate and spaced from the piston housing;

d. the orifices being dimensioned to, upon combustion of a metered amount of gaseous fuel in the combustion chamber, provide adequate pressure in the primary region of the combustion chamber for injecting flame under pressure into the secondary region of the combustion chamber and to provide adequate orifice surface area for injecting sufficient flame for combusting at an effective rate gaseous fuel in the secondary region of the combustion chamber.

27. The fastener driving tool of claim 26, wherein the accelerator plate comprises a disk radially oriented within the piston housing.

28. The fastener driving tool of claim 26, wherein the inner orifices are in a region of the plate spaced from the center of the plate and from the piston housing are about half way between the center of the plate and a circle defined by the outer orifices.

29. The fastener driving tool of claim 26, wherein the accelerator plate further comprises a slot.

30. The fastener driving tool of claim 29, wherein the slot in the accelerator plate is radially oriented, intersects an outer edge of the accelerator plate, and has a length less than or equal to a radius of the accelerator plate.

31. The fastener driving tool of claim 29, wherein the accelerator plate slot is arranged and configured to receive a fuel metering tube.

32. A fastener driving tool operable through an internal combustion driven piston, the tool comprising:

a. a driver body comprising a piston housing, a piston slidably housed in the piston housing, a driving member coupled to the piston;

a combustion chamber defined by the body, piston housing, and piston;

the piston and driving member being arranged and configured to drive a fastener upon combustion of a metered amount of gaseous fuel in the combustion chamber;

b. the piston housing comprising an accelerator plate;

the accelerator plate being arranged and configured to divide the combustion chamber into a primary region and a secondary region and to direct ignited combustion gasses from the primary region into the secondary region of the combustion chamber;

c. the accelerator plate comprising a plate oriented to fill a cross-section of the piston housing generally perpendicular to an axis of the piston housing;

the accelerator plate defining a plurality of outer orifices proximal to the piston housing and a plurality of inner orifices in a region of the plate spaced from the center of the accelerator plate and spaced from the piston housing;

d. the accelerator plate further comprising a slot.

33. The fastener driving tool of claim 32, wherein the slot in the accelerator plate is radially oriented, intersects an outer edge of the accelerator plate, and has a length less than or equal to a radius of the accelerator plate.

34. The fastener driving tool of claim 32, wherein the accelerator plate slot is arranged and configured to receive a fuel metering tube.

35. The fastener driving tool of claim 32, wherein the accelerator plate comprises a disk radially oriented within the piston housing.

36. The fastener driving tool of claim 32, wherein the inner orifices are dimensioned to, upon combustion of a metered amount of gaseous fuel in the combustion chamber, provide adequate pressure in the primary region of the combustion chamber for injecting flame under pressure into the secondary region of the combustion chamber and to provide adequate orifice surface area for injecting sufficient flame for combusting at an effective rate gaseous fuel in the secondary region of the combustion chamber.

37. The fastener driving tool of claim 32, wherein the inner orifices are in a region of the plate spaced from the center of the plate and from the piston housing are about half way between the center of the plate and a circle defined by the outer orifices.