Internal combustion engine

Patent metadata

Field	Value
Publication number	US-10018100-B2
Application number	US-201615218934-A
Country	US
Kind code	B2
Filing date	Jul 25, 2016
Priority date	Jul 25, 2016
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

An internal combustion engine has a cooling jacket defined in the cylinder block for cooling at least an exhaust side of the cylinder. The cooling jacket at least partially surrounds the cylinder and includes a first cooling passage positioned between the exhaust passage and the first auxiliary exhaust passage, and a second cooling passage positioned between the exhaust passage and the second auxiliary exhaust passage. The cooling jacket on at least the exhaust side of the cylinder comprises an upper portion and a lower portion which are in fluid communication with each other via at least one of the first cooling passage and the second cooling passage.

First claim

What is claimed is:

1. An internal combustion engine comprising:
a crankcase;
a crankshaft adapted to rotate about a crankshaft axis and disposed at least in part in the crankcase;
a cylinder block connected to the crankcase, the cylinder block defining a cylinder having a cylinder axis;
a cylinder head connected to the cylinder block, the cylinder block disposed between the cylinder head and the crankcase,
a piston disposed in the cylinder and operatively connected to the crankshaft, the cylinder, the cylinder head and the piston together defining at least one combustion chamber;
an intake port defined by the cylinder block for allowing at least one combustion component to enter the combustion chamber;
an exhaust port defined by the cylinder block, on an exhaust side of the internal combustion engine, for allowing exhaust gas to exit the combustion chamber through an exhaust passage extending from the exhaust port in the cylinder block;
a first auxiliary exhaust port defined by the cylinder block and a second auxiliary exhaust port defined by the cylinder block, the first and second auxiliary exhaust ports positioned circumferentially one on either side of the exhaust port and connected to the cylinder for allowing exhaust gas to exit the combustion chamber;
a first auxiliary exhaust passage in the cylinder block extending from the first auxiliary port;
a second auxiliary exhaust passage in the cylinder block extending from the second auxiliary port;
a cooling jacket defined in the cylinder block for cooling at least an exhaust side of the cylinder, the cooling jacket at least partially surrounding the cylinder and including a first cooling passage positioned between the exhaust passage and the first auxiliary exhaust passage, and a second cooling passage positioned between the exhaust passage and the second auxiliary exhaust passage, the cooling jacket on at least the exhaust side of the cylinder comprising an upper portion and a lower portion, the upper and lower portions of the cooling jacket being in fluid communication with each other via at least one of the first cooling passage and the second cooling passage.

2. The internal combustion engine of claim 1 , wherein the first cooling passage is formed in the cylinder block, proximate the cylinder, and between the first auxiliary exhaust passage and the exhaust passage, and the second cooling passage is formed in the cylinder block, proximate the cylinder, and inbetween the second auxiliary exhaust passage and the exhaust passage.

3. The internal combustion engine of claim 1 , wherein the first cooling passage is formed in a first bridge of the cylinder block, the first bridge being proximate the cylinder and separating the first auxiliary exhaust passage from the exhaust passage, and wherein the second cooling passage is formed in a second bridge of the cylinder block, the second bridge being proximate the cylinder and separating the second auxiliary exhaust passage from the exhaust passage.

4. The internal combustion engine of claim 3 , wherein the first cooling passage is the most proximate part of the cooling jacket to the cylinder in the first bridge, and the second cooling passage is the most proximate part of the cooling jacket to the cylinder in the second bridge.

5. The internal combustion engine of claim 1 , wherein the first cooling passage and the second cooling passage extend in a direction from the cylinder head to the crankcase.

6. The internal combustion engine of claim 1 , wherein the first cooling passage has a first cooling passage axis, and the second cooling passage has a second cooling passage axis, the first and second cooling passage axes being substantially parallel to one another.

7. The internal combustion engine of claim 1 , wherein the first and the second cooling passages are cylindrical.

8. The internal combustion engine of claim 1 , wherein the cooling jacket is arranged to contain coolant therein, the first and second cooling passages being arranged to allow coolant to flow therethrough in a direction from the lower portion of the cooling jacket to the upper portion of the cooling jacket.

9. The internal combustion engine of claim 1 , wherein the first and the second auxiliary exhaust ports are positioned circumferentially proximate the exhaust port.

10. The internal combustion engine of claim 1 , wherein at least a portion of the cooling jacket extends around the first and the second auxiliary exhaust passages, along at least a portion of a length of the first and the second auxiliary exhaust passages.

11. The internal combustion engine of claim 1 , wherein the cooling jacket is a first cooling jacket, the internal combustion engine further comprising a second cooling jacket at least partially surrounding the crankcase, the second cooling jacket being fluidly connected to the first cooling jacket.

12. The internal combustion engine of claim 11 , wherein the first and second cooling jackets are part of a cooling circuit, the cooling circuit further including:
an outlet at the cylinder head, the outlet being connected via an external conduit to a pump positioned at a lower portion of the crankcase for pumping coolant through the first and second cooling jackets and for receiving coolant from the cylinder head via the conduit.

13. The internal combustion engine of claim 1 , wherein the internal combustion engine is a two-stroke engine, and further comprises scavenge ports.

14. The internal combustion engine of claim 1 , wherein the cylinder comprises at least two adjacent cylinders.

15. The internal combustion engine of claim 1 , wherein the internal combustion engine is a two-stroke engine, the first cooling passage being formed in the cylinder block, proximate the cylinder, and in a first bridge between the first and auxiliary exhaust passage and the exhaust passage, and the second cooling passage being formed in the cylinder block, proximate the cylinder, in a second bridge between the second auxiliary exhaust passage and the exhaust passage, wherein the first and second cooling passages are substantially upright and are arranged to allow coolant contained within the cooling jacket to flow from the lower portion of the cooling jacket to the upper portion of the cooling jacket.

16. A snowmobile comprising:
a frame having a forward end and a rearward end;
a drive track assembly disposed below and supporting the rearward end of the frame;
a front suspension connected to the forward end of the frame;
two skis connected to the front suspension;
an internal combustion engine as claimed in claim 1 , the internal combustion engine mounted on the frame and operatively connected to the drive track via a drive train for delivering propulsive power to the drive track.

17. An internal combustion engine comprising:
a crankcase;
a crankshaft adapted to rotate about a crankshaft axis and disposed at least in part in the crankcase;
a cylinder block connected to the crankcase, the cylinder block defining a cylinder having a cylinder axis;
a cylinder head connected to the cylinder block, the cylinder block disposed between the cylinder head and the crankcase,
a piston disposed in the cylinder and operatively connected to the crankshaft, the cylinder, the cylinder head and the piston together defining at least one combustion chamber;
an intake port defined by the cylinder block for allowing at least one combustion component to enter the combustion chamber;
an exhaust port defined by the cylinder block, on an exhaust side of the internal combustion engine, for allowing exhaust gas to exit t

Assignees

• Brp Rotax Gmbh & Co Kg

Inventors

• WIESINGER Petra
• Rothkegel Thomas
• Gumpesberger Michael

Classifications

• F02F1/22

  characterised by having ports in cylinder wall for scavenging or charging · CPC title

• B62M2027/023

  Snow mobiles characterised by engine mounting arrangements · CPC title

• F02B75/18

  Multi-cylinder engines (scavenging aspects F02B25/00) · CPC title

• F01P3/02 Primary

  Arrangements for cooling cylinders or cylinder heads · CPC title

• F01P2003/021

  Cooling cylinders · CPC title