HYDRAULIC SYSTEM FOR DOUBLE PISTON

• US 20140083810A1
• Filed: 12/18/2012
• Published: 03/27/2014
• Est. Priority Date: 09/21/2012
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Hwang, Jin Young
• Granted Patent: US 9,291,214 B2
• Time in Patent Office: Days
• US Class Current: 192/85.63
• CPC Class Codes: F16D 2048/0209 characterised by fluid valves having control pistons, e.g. spools
• CPC Class Codes: F16D 2048/0212 Details of pistons for master or slave cylinders especially adapted for fluid control for other details of pistons in master or slave cylinders F16D2025/081 or F16D25/082
• CPC Class Codes: F16D 2048/0278 Two valves in series arrangement for controlling supply to actuation cylinder
• CPC Class Codes: F16D 25/0638 with more than two discs, e.g. multiple lamellae
• CPC Class Codes: F16D 48/02 Control by fluid pressure
• CPC Class Codes: F16D 48/062 of a clutch system with a plurality of fluid actuated clutches

Abstract

A hydraulic system for a double piston includes a double piston that includes an operation piston with a first operation side and a second operation side, a first piston port for supplying hydraulic pressure to the first operation side, and a second piston port for supplying hydraulic pressure to the second operation side, a solenoid valve that receives a clutch control pressure and communicates with the first piston port through a first channel, a switch valve that receives the clutch control pressure from the solenoid valve, may be connected with the second piston port through a second channel, and selectively transmits the clutch control pressure to the second piston port, and a manual valve that receives a line pressure and selectively transmits the line pressure to the switch valve such that the clutch control pressure may be selectively transmitted to the second operation side through the second channel.

Claims

1. A hydraulic system for a double piston, comprising:

the double piston including;

an operation piston with a first operation side and a second operation side;

a first piston port for supplying a first hydraulic pressure to the first operation side; and

a second piston port for supplying a second hydraulic pressure to the second operation side;

a solenoid valve that receives a clutch control pressure and communicates with the first piston port through a first channel;

a switch valve that receives a portion of the clutch control pressure from the solenoid valve, is fluid-connected with the second piston port through a second channel, and selectively transmits the portion of the clutch control pressure to the second piston port; and

a manual valve that receives a line pressure and selectively transmits the line pressure to the switch valve such that the portion of the clutch control pressure is selectively transmitted to the second operation side through the second channel.

2. The hydraulic system of claim 1, wherein the manual valve transmits the line pressure to the switch valve such that the portion of the clutch control pressure is transmitted through the second channel, when a predetermined shifting range is selected.

3. The hydraulic system of claim 2, wherein the predetermined shifting range is a reverse speed range.

4. The hydraulic system of claim 1, wherein the double piston further includes:

an inner spline;

inner friction plates slidably disposed at the inner spline;

an outer spline;

outer friction plates slidably disposed at the outer spline and being alternate with the inner friction plates; and

an elastic member that elastically supports the operation piston, and

an operation rod,

wherein the operation rod presses the inner friction plates and the outer friction plates, when the first hydraulic pressure is supplied to the first operation side, or the first hydraulic pressure is supplied to the first operation side and the second hydraulic pressure is supplied to the second operation side.

5. The hydraulic system of claim 4, wherein the operation piston is slidably mounted in the outer spline.

6. The hydraulic system of claim 4, wherein the elastic member is mounted onto the outer spline.

7. The hydraulic system of claim 1, wherein the switch valve includes:

an inlet port for receiving the portion of the clutch control pressure transmitted from the solenoid valve;

an outlet port that communicates with the second channel; and

a control port that communicates with the manual valve to receive the line pressure.

8. The hydraulic system of claim 7,

wherein the switch valve includes:

a valve spool; and

a spring elastically supporting the valve spool, and

wherein the valve spool includes;

a first land that receives the line pressure through the control port; and

a second land that selectively connects the inlet port with the outlet port, together with the first land.

9. The hydraulic system of claim 1, wherein the solenoid valve is a proportional control solenoid valve.

10. The hydraulic system of claim 1, wherein the double piston is operated as a low and reverse clutch.

11. A hydraulic system for a double piston, comprising:

the double piston that includes;

an inner spline;

inner friction plates slidably disposed at the inner spline;

an outer spline;

outer friction plates slidably disposed at the outer spline to be alternate with the inner friction plates;

an operation piston having a first operation side and a second operation side and selectively pressing the inner friction plates and the outer friction plates;

an elastic member elastically supporting the operation piston;

a first piston port for supplying a first hydraulic pressure to the first operation side; and

a second piston port for supplying a second hydraulic pressure to the second operation side;

a proportional control solenoid valve that receives a clutch control pressure and communicates with the first piston port through a first channel;

a switch valve that receives a portion of the clutch control pressure from the solenoid valve, is connected with the second piston port through a second channel, and selectively transmits the clutch control pressure to the second piston port; and

a manual valve that receives a line pressure and selectively transmits the line pressure to the switch valve such that the portion of the clutch control pressure is selectively transmitted to the second operation side through the second channel.

12. The hydraulic system of claim 11, wherein the operation piston is slidably mounted in the outer spline.

13. The hydraulic system of claim 11, wherein the elastic member is mounted onto the outer spline.

14. The hydraulic system of claim 11, wherein the manual valve transmits the line pressure to the switch valve such that the portion of the clutch control pressure is transmitted through the second channel, when a predetermined shifting range is selected.

15. The hydraulic system of claim 11, wherein the predetermined shifting range is a reverse speed range.

16. The hydraulic system of claim 11,

wherein the switch valve has:

an inlet port for receiving the portion of the clutch control pressure transmitted from the solenoid valve;

an outlet port that communicates with the second channel; and

a control port that communicates with the manual valve to receive the line pressure,

wherein the switch valve includes;

a valve spool; and

a spring elastically supporting the valve spool, and

wherein the valve spool includes;

a first land that receives the line pressure through the control port; and

a second land that selectively connects the inlet port with the outlet port, together with the first land.

17. The hydraulic system of claim 11, wherein the double piston is operated as a low and reverse clutch.