Fastener-driving tool with one or more combustion chambers and an exhaust gas recirculation system

Patent metadata

Field	Value
Publication number	US-10875165-B2
Application number	US-201816042419-A
Country	US
Kind code	B2
Filing date	Jul 23, 2018
Priority date	Aug 2, 2017
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

Various embodiments of the present disclosure provide a combustion-powered fastener-driving tool including multiple combustion chambers and an exhaust gas recirculation system.

First claim

The invention claimed is:

1. A fastener-driving tool comprising:
a housing defining an air chamber;
a first set of components at least partially within the housing that define a first combustion chamber having a first volume;
a spark generator configured to generate a spark within the first combustion chamber;
a second set of components at least partially within the housing that define a second combustion chamber having a second volume greater than the first volume, wherein the second combustion chamber is in fluid communication with the first combustion chamber via multiple openings;
a cylinder within the housing and defining a piston chamber that is in fluid communication with the second combustion chamber;
a piston in the piston chamber and movable relative to the cylinder between a pre-firing position and a firing position;
a driver blade attached to the piston;
an exhaust gas recirculation (EGR) valve having an EGR valve inlet that is in fluid communication with the piston chamber via an EGR opening defined through the cylinder;
an EGR valve recirculation outlet that is in fluid communication with an EGR conduit, the EGR conduit having an EGR conduit outlet that is in fluid communication with the air chamber; and
an EGR valve exhaust outlet that is in fluid communication with an exhaust conduit that is in fluid communication with the atmosphere.

2. The fastener-driving tool of claim 1 , further comprising a fuel-dispensing system having a fuel-dispensing conduit in fluid communication with the first combustion chamber, the fuel-dispensing conduit comprising a fuel-dispensing conduit outlet.

3. The fastener-driving tool of claim 2 , wherein the fuel-dispensing conduit is sized and shaped to route fuel from an outlet of a fuel canister to the fuel-dispensing conduit outlet.

4. The fastener-driving tool of claim 3 , further comprising:
a workpiece-contact element movable relative to the housing between an extended position and a retracted position; and
one or more mechanical linkages connecting the workpiece-contact element to the fuel-dispensing system such that, when the fuel canister is received in the fuel-dispensing system, movement of the workpiece-contact element from the extended position to the retracted position causes the fuel to be dispensed from the outlet of the fuel canister into the fuel-dispensing conduit.

5. The fastener-driving tool of claim 3 , wherein the EGR valve is movable between an open configuration in which the EGR valve enables fluid to flow from the EGR valve inlet to the EGR valve recirculation outlet and a closed configuration in which the EGR valve prevents fluid from flowing from the EGR valve inlet to the EGR valve recirculation outlet.

6. The fastener-driving tool of claim 5 , wherein the EGR valve enables fluid to flow from the EGR valve inlet to the EGR valve exhaust outlet when in the open configuration and prevents fluid from flowing from the EGR valve inlet to the EGR valve exhaust outlet when in the closed configuration.

7. The fastener-driving tool of claim 6 , further comprising a check valve in fluid communication with the exhaust conduit and configured to enable fluid to flow from the EGR valve exhaust outlet through the exhaust conduit to the atmosphere and to prevent fluid from flowing from the atmosphere through the exhaust conduit to the EGR valve exhaust outlet.

8. The fastener-driving tool of claim 5 , wherein part of the EGR conduit is adjacent the fuel-dispensing conduit.

9. The fastener-driving tool of claim 5 , wherein the EGR conduit is positioned such that at least some of any fluid exiting the EGR conduit outlet contacts at least part of the fuel-dispensing conduit.

10. The fastener-driving tool of claim 5 , further comprising a first check valve configured to enable fluid to flow from the atmosphere into the air chamber and to prevent fluid from flowing from the air chamber to the atmosphere through the first check valve.

11. The fastener-driving tool of claim 10 , further comprising a second check valve configured to enable fluid to flow from the air chamber to the first combustion chamber and to prevent fluid from flowing from the first combustion chamber to the air chamber.

12. The fastener-driving tool of claim 11 , further comprising a third check valve configured to enable fluid to flow from the air chamber to the second combustion chamber and to prevent fluid from flowing from the second combustion chamber to the air chamber.

13. The fastener-driving tool of claim 5 , further comprising an EGR conduit check valve configured to enable fluid to flow from the EGR valve recirculation outlet through the EGR conduit to the air chamber and to prevent fluid from flowing from the air chamber through the EGR conduit to the EGR valve recirculation outlet.

14. The fastener-driving tool of claim 12 , wherein the EGR valve further comprises an EGR valve piston chamber outlet in fluid communication with a piston chamber conduit that is in fluid communication with the piston chamber, wherein the EGR valve enables fluid to flow from the EGR valve inlet to the EGR valve piston chamber outlet when in the open configuration and prevents fluid from flowing from the EGR valve inlet to the EGR valve piston chamber outlet when in the closed configuration.

15. The fastener-driving tool of claim 14 , further comprising a check valve in fluid communication with the piston chamber conduit and configured to enable fluid to flow from the EGR valve piston chamber outlet through the piston chamber conduit to the piston chamber and to prevent fluid from flowing from the piston chamber through the piston chamber conduit to the EGR valve piston chamber outlet.

16. The fastener-driving tool of claim 1 , wherein the first volume is 1.4% to 7.4% of the second volume.

17. The fastener-driving tool of claim 1 , wherein the first volume is 2.4% to 3.7% of the second volume.

Assignees

• Illinois Tool Works

Inventors

• Fan Chinbay Q
• Talano Patrick
• Haberstroh James

Classifications

• F01B11/04

  Engines combined with reciprocatory driven devices, e.g. hammers · CPC title

• B25C1/08 Primary

  operated by combustion pressure · CPC title

• F02B63/02

  for hand-held tools · CPC title

• F02B71/04

  Adaptations of such engines for special use; Combinations of such engines with apparatus driven thereby · CPC title