Engine system

Abstract

An object of the invention is to provide an engine system driving an engine by using a hydrogen rich gas generated from a medium chemically repeating a hydrogen absorption and a hydrogen desorption as one of fuels, in which the engine system can efficiently generate a hydrogen rich gas from the medium. In an engine system which mounts a medium chemically repeating a hydrogen absorption and a hydrogen desorption thereon, is provided with a hydrogen supplying apparatus generating or storing a hydrogen rich gas from the medium, and drives an engine by using the hydrogen rich gas as one of fuels, the engine system has a detecting portion detecting an operating state of the engine, and a medium supplying amount control means controlling a supplying amount of the medium supplied to the hydrogen supplying apparatus in correspondence to a result of detection of the detecting portion.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a schematic view of an engine system in which a hydrogen supplying apparatus is installed to an exhaust pipe;

FIG. 2 is a schematic view of the hydrogen supplying apparatus;

FIG. 3 is a view of a relation between an operating region of an engine and a supplied fuel;

FIG. 4 is a view of a relation between a catalyst temperature and a conversion rate;

FIG. 5 is a view of a relation between a hydrogenating medium supplying amount to the hydrogen supplying apparatus and the conversion rate;

FIG. 6 is a control flow chart in accordance with a catalyst temperature change of the hydrogen supplying apparatus;

FIG. 7 is a view showing each of methods for controlling a heat supplying amount to the hydrogen supplying apparatus;

FIG. 8 is a control flow chart in accordance with a storage amount change of a hydrogen rich gas;

FIG. 9 is a view judging a catalyst deterioration within the hydrogen supplying apparatus;

FIG. 10 is a view showing a control of an air fuel ratio and an ignition timing executed at a time of switching a fuel;

FIG. 11 is a view of a relation between an excess air ratio and an NOx discharging amount at a time of burning the hydrogen rich gas;

FIG. 12 is a view of a relation between a purifying rate of a three-way catalyst and the excess air ratio;

FIG. 13 is a view of a catalyst temperature change until the engine is activated to the three-way catalyst after starting;

FIG. 14 is a system schematic view of a compression ignition combustion type engine system in which the hydrogen supplying apparatus is installed to an exhaust pipe; and

FIG. 15 is a view of a relation between a hydrogen concentration and an ignition timing.

Claims

1. An engine system which mounts a medium chemically repeating a hydrogen absorption and a hydrogen desorption thereon, is provided with a hydrogen supplying apparatus generating or storing a hydrogen rich gas from said medium, and drives an engine by using said hydrogen rich gas as one of fuels, comprising: a detecting portion detecting an operating state of the engine; anda medium supplying amount control means controlling a supplying amount of said medium supplied to said hydrogen supplying apparatus in correspondence to a result of detection of said detecting portion.

2. An engine system as claimed in claim 1, wherein an engine estimated torque and an engine rotational speed are detected by said detecting means.

3. An engine system which mounts a medium chemically repeating a hydrogen absorption and a hydrogen desorption thereon, is provided with a hydrogen supplying apparatus generating or storing a hydrogen rich gas from said medium, and drives an engine by using said hydrogen rich gas as one of fuels, comprising: at least one of a catalyst temperature estimating means estimating a temperature of a catalyst within the hydrogen supplying apparatus, and a medium supplying amount control means controlling a supplying amount of said medium supplied to said hydrogen supplying apparatus or a heat supplying amount control means controlling a supplying amount of a heat supplied to said hydrogen supplying apparatus, on the basis of the catalyst temperature estimated by said catalyst temperature estimating means.

4. An engine system as claimed in claim 3, wherein in the case that a temperature of the catalyst within said hydrogen supplying apparatus detected by said catalyst temperature estimating means is lower than a predetermined temperature, the engine system executes at least any one control of reducing a supply amount of said medium supplied to said hydrogen supply apparatus by said medium supply amount control means, and increasing a heat supply amount supplied to said hydrogen supplying apparatus by said heat supply amount control means.

5. An engine system as claimed in claim 3, wherein in the case that a temperature of the catalyst within said hydrogen supplying apparatus detected by said catalyst temperature estimating means is higher than a predetermined temperature, the engine system executes at least any one control of increasing a supply amount of said medium supplied to said hydrogen supply apparatus by said medium supply amount control means, and reducing a heat supply amount supplied to said hydrogen supplying apparatus by said heat supply amount control means.

6. An engine system as claimed in claim 3, wherein the engine system has at least one of a hydrogen rich gas supply amount control means controlling a supply amount of said hydrogen rich gas supplied to the engine, and a medium supply amount control means controlling a supply amount of said medium supplied to the engine.

7. An engine system as claimed in claim 3, wherein a heat supply amount supplied to the hydrogen supplying apparatus by said heat supply amount control means controls at least any one of a flow rate of an exhaust gas discharged from the engine, an ignition timing by a spark plug provided in the engine, an opening and closing timing of an exhaust valve provided in the engine, a heat supply amount supplied from the other heat sources than the engine mounted on the motor vehicle, and a heating amount generated by a heating apparatus installed in said hydrogen supplying apparatus.

8. An engine system as claimed in claim 3, wherein the engine system is provided with a storage apparatus storing said hydrogen rich gas, and at least one detecting means of a storage amount detecting means detecting a storage amount of said hydrogen rich gas stored in said storage apparatus, and a concentration detecting means detecting a concentration of said stored hydrogen rich gas, and wherein the engine system controls at least any one of a supply amount of said medium supplied to said hydrogen supplying apparatus by said medium supply amount control means, a supply amount of said hydrogen rich gas supplied to the engine by said hydrogen rich gas supply amount control means, and a supply amount of said medium supplied to the engine by said medium supply amount control means, in correspondence to a result of detection of said detecting means.

9. An engine system which is provided with a hydrogen supplying apparatus generating a hydrogen rich gas from a medium chemically repeating a hydrogen absorption and a hydrogen desorption, and a separating apparatus separating a mixture of a hydrogen rich gas generated by said hydrogen supplying apparatus and a dehydrogenating medium, and drives an engine by using said hydrogen rich gas separated by said separating apparatus as one of fuels, wherein the engine system has a hydrogen rich gas concentration detecting means detecting a concentration of the hydrogen rich gas separated by said separating apparatus, and an ignition timing control means controlling an ignition timing by a spark plug provided in the engine, on the basis of the hydrogen rich gas concentration detected by said hydrogen rich gas concentration detecting means.

10. An engine system which mounts a medium chemically repeating a hydrogen absorption and a hydrogen desorption thereon, is provided with a hydrogen supplying apparatus generating or storing a hydrogen rich gas from said medium, and drives an engine by using said hydrogen rich gas as one of fuels, wherein said hydrogen supplying apparatus is installed in an exhaust pipe of the engine, and the engine system has a temperature detecting means installed in an exhaust gas upstream side of said hydrogen supplying apparatus, a temperature detecting apparatus installed in an exhaust gas downstream side of said hydrogen supplying apparatus, and a catalyst deterioration judging means judging a deteriorated state of a catalyst within said hydrogen supplying apparatus on the basis of a difference of temperatures detected by said exhaust gas upstream side and downstream side temperature detecting apparatuses.

11. An engine system as claimed in claim 10, wherein said catalyst deterioration judging means judges the deteriorated state of the catalyst on the basis of a predetermined engine operating state and the difference of the temperatures in said exhaust gas upstream side and downstream side at a time of generating a predetermined amount of said hydrogen rich gas.

12. An engine system as claimed in claim 10, wherein the engine system has a means giving a warning to a user in the case that the deteriorated state of the catalyst judged by said catalyst deterioration judging means becomes equal to or more than a predetermined value.

13. An engine system as claimed in claim 10, wherein the engine system has a medium supply amount control means controlling a supply amount of said medium supplied to said hydrogen supplying apparatus on the basis of the deteriorated state of the catalyst judged by said catalyst deterioration judging means.

14. An engine system provided with a hydrogen supplying apparatus generating a hydrogen rich gas from a medium chemically repeating a hydrogen absorption and a hydrogen desorption, and a three-way catalyst for purifying an exhaust gas, and driving an engine by using said hydrogen rich gas and said medium as one of fuels, comprising: an ignition timing control means controlling an ignition timing by a spark plug provided in the engine in correspondence to a supplying amount rate of said medium and said hydrogen rich gas supplied to the engine; andan excess air ratio control means controlling an excess air ratio of an air fuel mixture supplied to the engine,wherein the excess air ratio is controlled in a range between 0.95 and 1.05 or between 1.8 and 5.0 by said excess air ratio control means.

15. An engine system as claimed in claim 14, wherein said excess air ratio control means controls the excess air ratio in the range between 0.95 and 1.05 in the case that the fuel supplied to the engine is constituted only by said medium, controls the excess air ratio in the range between 0.95 and 1.05 or between 1.8 and 5.0 in the case that the fuel supplied to the engine is constituted by said hydrogen rich gas and said medium, and controls the excess air ratio in the range between 1.8 and 5.0 in the case that the fuel supplied to the engine is constituted only by said hydrogen rich gas.

16. An engine system which mounts a medium chemically repeating a hydrogen absorption and a hydrogen desorption thereon, is provided with a hydrogen supplying apparatus generating or storing a hydrogen rich gas from said medium, and drives an engine by using said hydrogen rich gas as one of fuels, wherein an exhaust pipe of the engine is provided with said hydrogen supplying apparatus and a purifying catalyst for purifying an exhaust gas of the engine, and said purifying catalyst is installed closer to the engine than said hydrogen supplying apparatus, or said hydrogen supplying apparatus and said purifying catalyst are integrally formed.

17. An engine system as claimed in claim 16, wherein the engine system is provided with a catalyst temperature estimating means estimating a catalyst temperature of said purifying catalyst, and has a control apparatus executing a control of inhibiting a supply of said medium to the engine or lowering a supply amount of said medium supplied to the engine, in the case that the catalyst temperature estimated on the basis of said catalyst temperature estimating means is equal to or less than a predetermined value.

18. An engine system as claimed in claim 17, wherein said control apparatus supplies only said hydrogen rich gas as said fuel to the engine at a time of starting the engine.

19. An engine system as claimed in claim 16, wherein the engine system comprises: a storage amount detecting means detecting a storage amount of said hydrogen rich gas stored in the storage apparatus;a hydrogen rich gas storage amount detecting means judging whether or not the storage amount of said hydrogen rich gas detected by said storage amount detecting means is in a range of a predetermined value, at a time of receiving an engine stop signal; anda medium supply means supplying said medium to said hydrogen supplying apparatus in the case that the storage amount of said hydrogen rich gas is judged to be equal to or less than a predetermined value by said hydrogen rich gas storage amount judging means.

20. An engine system which mounts a medium chemically repeating a hydrogen absorption and a hydrogen desorption thereon, is provided with a hydrogen supplying apparatus generating or storing a hydrogen rich gas from said medium, and drives an engine by using said hydrogen rich gas as one of fuels, wherein the engine system comprises:a hydrogen rich gas supplying apparatus supplying said hydrogen rich gas as a fuel to an engine;a medium fuel supplying apparatus directly supplying a component including said medium into a cylinder; anda fuel supply timing control means supplying the component including said medium into the cylinder during a piston compression period so as to execute an autoignition combustion, after supplying said hydrogen rich gas to the engine.