Power unit

• US 20030089107A1
• Filed: 11/15/2002
• Published: 05/15/2003
• Est. Priority Date: 02/19/2001
• Status: Active Grant

• Current Assignee: Danfoss Power Solutions Ltd. (Danfoss A/S)
• Original Assignee: Sauer-Danfoss Daikin Ltd.
• Inventors: Tani, Nobuyuki
• Granted Patent: US 7,051,840 B2
• Time in Patent Office: Days
• US Class Current: 60/487
• CPC Class Codes: F01M 1/02 using lubricating pumps pumps in general F04; lubricating pumps per se F16N
• CPC Class Codes: F16H 2037/088 Power split variators with summing differentials, with the input of the CVT connected or connectable to the input shaft
• CPC Class Codes: F16H 39/14 with cylinders carried in rotary cylinder blocks or cylinder-bearing members
• CPC Class Codes: F16H 47/04 the mechanical gearing being of the type with members having orbital motion
• CPC Class Codes: F16H 57/0412 Cooling or heating; Control of temperature
• CPC Class Codes: F16H 61/40 hydrostatic
• CPC Class Codes: F16H 61/4165 Control of cooling or lubricating

Abstract

In a power unit comprising an engine (13) and an HST (24) which are formed into an integral body, a lubricating oil for use in the engine and an operating oil of the HST (24) are commonized. After being cooled, the common oil is fed from the side of the engine (13) to the HST (24). Such arrangement suppresses the drop in viscosity of the common oil and prevents the drop in efficiency and the occurrence of seizing on the side of the HST (24).

Claims

1. A power unit which comprises an engine (13) and a transmission mechanism (T) including a hydro static transmission (24) which are integrally formed and in which a common oil is shared as a lubricating oil and as an operating oil,

said power unit further comprising:

oil feed means (70, 15) for circulating said common oil between said engine (13) and said hydro static transmission (24), and

cooling means (40d, 77) for cooling said common oil in an oil feed route (R) from said engine (13) to said hydro static transmission (24).

2. The power unit of claim 1, wherein said transmission mechanism (T) comprises a hydro mechanical transmission which is a combination of said hydro static transmission (24) and a mechanical transmission (23).

3. The power unit of either claim 1 or claim 2,

wherein:

said cooling means comprises a heat release part (40d) provided on an outer surface of a casing (40, 42), and

said oil feed route (R) is so arranged as to lie along said heat release part (40d).

4. The power unit of either claim 1 or claim 2, wherein said cooling means comprises an oil cooler (77) provided in said oil feed route (R).

5. The power unit of any one of claims 1-4, wherein said oil feed means comprises a charge pump (70) of said hydro static transmission (24).

6. The power unit of any one of claims 1-4, wherein said oil feed means comprises a lubricating pump (15) of said engine (13).