Engine cooling structure

Patent metadata

Field	Value
Publication number	US-10934968-B2
Application number	US-202016738172-A
Country	US
Kind code	B2
Filing date	Jan 9, 2020
Priority date	Jan 17, 2019
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

An engine cooling structure includes a cylinder block including a block inner peripheral wall that defines a water jacket and a block outer peripheral wall, a spacer housed in the water jacket, and a cooler provided outside the engine body. The spacer includes: a peripheral wall surrounding the block inner peripheral wall; and a dividing wall protruding from the peripheral wall to divide the water jacket into an upper passage and lower passages below the upper passage. A coolant introduced from a coolant inlet into the upper passage passes through an inter-bore part of the block inner peripheral wall. The coolant in the lower passages is introduced into the cooler through a coolant exit.

First claim

The invention claimed is:

1. An engine cooling structure for cooling an engine body including a plurality of cylinders by using a coolant, the engine cooling structure comprising:
a cylinder block including: a block inner peripheral wall defining the plurality of cylinders; and a block outer peripheral wall surrounding the block inner peripheral wall to define a water jacket through which the coolant circulates between the block outer peripheral wall and the block inner peripheral wall;
a spacer housed in the water jacket; and
a cooler provided outside the engine body,
wherein the block outer peripheral wall includes: a coolant inlet configured to introduce the coolant into the water jacket; and a coolant exit configured to lead out the coolant from the water jacket to the cooler,
the block inner peripheral wall includes an inter-bore part positioned between adjacent cylinders of the plurality of cylinders,
the spacer includes: a peripheral wall surrounding the block inner peripheral wall; and a dividing wall protruding from the peripheral wall to divide the water jacket into an upper passage and a lower passage below the upper passage,
the peripheral wall includes an upper peripheral wall above the dividing wall, and a lower peripheral wall below the dividing wall,
the coolant inlet is provided at a position to introduce the coolant into the upper passage,
the upper passage allows the coolant introduced from the coolant inlet to come in direct contact with the inter-bore part,
the coolant exit is provided at a position facing the lower peripheral wall of the spacer under the dividing wall so as to lead out the coolant in the lower passage to the cooler, and
the cooler cools a predetermined cooling object by the coolant led out from the coolant exit.

2. The engine cooling structure according to claim 1 , wherein
the coolant exit includes a first exit and a second exit provided at different positions on the block outer peripheral wall,
the cooler includes a first cooler and a second cooler that cool different cooling objects,
the first exit leads out the coolant in the lower passage to the first cooler, and
the second exit leads out the coolant in the lower passage to the second cooler.

3. The engine cooling structure according to claim 2 , further comprising:
a water pump configured to discharge the coolant to the coolant inlet; and
a first passage connecting the water pump and the first exit outside the cylinder block,
wherein the first cooler is an EGR cooler that cools an EGR gas that is an exhaust gas recirculated to an intake air to be introduced into the engine body out of an exhaust gas discharged from the engine body, and
the EGR cooler and a first flow regulating device are provided in the first passage, the first flow regulating device being configured to change a flow rate of the coolant that circulates through the first passage.

4. The engine cooling structure according to claim 3 , wherein the first flow regulating device includes a first valve provided in an openable and closable manner in the first passage, and is configured to switch an opening degree of the first valve among a fully closed position, a fully open position, and an intermediate opening degree between the fully closed position and the fully open position.

5. The engine cooling structure according to claim 2 , further comprising:
a water pump configured to discharge the coolant to the coolant inlet; and
a second passage connecting the water pump and the second exit outside the cylinder block,
wherein the second cooler is an oil cooler that cools a lubricant supplied to the engine body, and
the oil cooler and a second flow regulating device are provided in the second passage, the second flow regulating device being configured to change a flow rate of the coolant that circulates through the second passage.

6. The engine cooling structure according to claim 5 , wherein the second flow regulating device includes a second valve provided in an openable and closable manner in the second passage, when a temperature of the coolant circulating through the second passage is equal to or higher than a predetermined temperature, the second flow regulating device fully opens the second valve, and when the temperature of the coolant is lower than the predetermined temperature, the second flow regulating device fully closes the second valve.

7. The engine cooling structure according to claim 1 , wherein
the cooler includes an EGR (exhaust gas recirculation) cooler that cools an EGR gas that is an exhaust gas recirculated to an intake air to be introduced into the engine body out of an exhaust gas discharged from the engine body, and an oil cooler that cools a lubricant supplied to the engine body,
the coolant exit includes a first exit formed in an exhaust side wall of the block outer peripheral wall, and a second exit formed in an intake side wall of the block outer peripheral wall,
the first exit leads out the coolant in the lower passage to the EGR cooler, and
the second exit leads out the coolant in the lower passage to the oil cooler.

8. An engine cooling structure for cooling an engine body including a plurality of cylinders by using a coolant, the engine cooling structure comprising:
a cylinder block including: a block inner peripheral wall defining the plurality of cylinders; and a block outer peripheral wall surrounding the block inner peripheral wall to define a water jacket through which the coolant circulates between the block outer peripheral wall and the block inner peripheral wall;
a spacer housed in the water jacket; and
a cooler provided outside the engine body and including an EGR (exhaust gas recirculation) cooler that cools an EGR gas that is an exhaust gas recirculated to an intake air to be introduced into the engine body out of an exhaust gas discharged from the engine body, and an oil cooler that cools a lubricant supplied to the engine body,
wherein the block outer peripheral wall includes: a coolant inlet configured to introduce the coolant into the water jacket; and a coolant exit configured to lead out the coolant from the water jacket to the cooler,
the block inner peripheral wall includes an inter-bore part positioned between adjacent cylinders of the plurality of cylinders,
the spacer includes: a peripheral wall surrounding the block inner peripheral wall; and a dividing wall protruding from the peripheral wall to divide the water jacket into an upper passage and a lower passage below the upper passage,
the coolant inlet is provided at a position to introduce the coolant into the upper passage,
the upper passage allows the coolant introduced from the coolant inlet to come in direct contact with the inter-bore part,
the coolant exit is provided at a position to lead out the coolant in the lower passage to the cooler,
the cooler cools a predetermined cooling object by the coolant led out from the coolant exit,
the coolant exit includes a first exit formed in an exhaust side wall of the block outer peripheral wall, and a second exit formed in an intake side wall of the block outer peripheral wall,
the first exit leads out the coolant in the lower passage to the EGR cooler, and
the second exit leads out the coolant in the lower passage to the oil cooler.

Assignees

• Mazda Motor

Inventors

• Watanabe Shinji
• Takahata Tatsuya
• Hayamizu Yoshiaki
• Watanabe Keita
• Kawaguchi Mikimasa

Classifications

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02F1/108

  Siamese-type cylinders, i.e. cylinders cast together · CPC title

• F02F1/14 Primary

  Cylinders with means for directing, guiding or distributing liquid stream · CPC title

• F02F2001/104

  using an open deck, i.e. the water jacket is open at the block top face · CPC title

• F02F1/166

  Spacer decks · CPC title