DESC:SYSTEM FOR LOAD ADAPTIVE DAMPING IN SHOCK ABSORBER

Field of the invention:

The present invention relates to a suspension system of an automobile and, more particularly, to a system for load adaptive damping for user selectable damping adjustment in a shock absorber.

Background of the invention:

Generally, present technology in user selectable damping adjustment type shock absorber has multiple ways to divert an oil flow to change a damping force as per the user selection while driving a vehicle.

One way of adjusting the damping by diverting the oil flow within the shock absorber is to use pull out mechanism having fixed setting to adjust the damping.

Other option of adjusting the damping is to use a motor to drive a spool to adjust the damping.

However, using pull out mechanism to adjust the damping of the shock absorber have only two settings of adjusting the damping and does not provide comfort damping while driving.

Further, using the motor to drive the spool has multiple settings possibility, but needs servo or stepper motor to precisely control the number of rotations and also needs control logic to prevent motor overrun and burn out. Further, the induction motors provide drive power until the input power is shut down and at the end of stroke, the connected mechanism stops, leading the motor to over load and burn out.

Accordingly, there exist a need to provide load adaptive damping for user selectable damping adjustment in the shock absorber, that overcomes above-mentioned drawbacks of the prior art.

Objects of the invention:

An object of the present invention is to avoid burnout of a motor while adjusting damping in user selectable damping type shock absorber.

Another object of the present invention is to increase life of the motor used in adjusting the damping in the user selectable damping type shock absorber.

Summary of the invention:

Accordingly, the present invention provides a system for load adaptive damping in a shock absorber to adjust damping based on user’s selection. The shock absorber includes a hollow piston rod, a plunger shaft, a spool, a piston assembly, a control orifice and a multi-stage disc/valve stack. The plunger shaft is accommodated within the hollow piston rod. The spool is operably connected to the plunger shaft. The control orifice allows an oil flow therethrough. The multi-stage disc/valve stack is operably connected to the spool for controlling the oil flow path through the control orifice. The system comprises of a motor, a coupler and a slip clutch. The motor is operably connected to the plunger shaft to drive the spool for adjusting the damping. The coupler is operably connected to the motor. The slip clutch is operably connected between the hollow piston rod and the motor by means of the coupler. The slip clutch is adapted to move the spool for any one of opening and closing the multi-stage disc/valve stack to change the oil flow path thereby varying damping forces.

When the user selects a hard setting of the shock absorber, the slip clutch moves the spool to close the multi-stage disc/valve stack. When the user selects a soft setting, the slip clutch moves the spool to open the multi-stage disc/valve stack. The plunger shaft is moved by the motor through the slip clutch to change the oil flow path to achieve varying damping forces as per the user’s selection. The system is adjusted by the user for the hard setting during running the vehicle in sports mode, on smooth road / highway and the soft setting for running the vehicle on rough roads. The system prevents overloading and burning out of the motor and also increases life of the motor.

Brief description of the drawings:

Figure 1 shows a system for load adaptive damping for user selectable damping adjustment in a shock absorber, in accordance with the present invention;

Figure 2 shows the system of figure 1 with hard setting to adjust the damping of the shock absorber; and

Figure 3 shows the system of figure 1 with soft setting to adjust the damping of the shock absorber.

Detailed Description of the invention:

The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiment.

The present invention provides a system for load adaptive damping for user selectable damping adjustment in a shock absorber. The system avoids burnout of a motor used in load adaptive damping and also increases life of the motor.

This present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description.

Referring to figures 1 to 3, a system for load adaptive damping (100) (hereinafter referred as “the system (100)”) to adjust damping based on user’s selection in a shock absorber (80) is shown. The shock absorber (80) comprises of a hollow piston rod (70), a plunger shaft (62), a spool (72), a piston assembly (74), a control orifice (76) and a multi-stage disc/valve stack (78). The plunger shaft (62) is accommodated within the hollow piston rod (70). The spool (72) is operably connected to the plunger shaft (62). The control orifice (76) is configured on the piston assembly (74) for allowing oil flow therethrough. By changing the oil flow path, the shock absorber (80) is made either to behave hard or soft. The multi-stage disc/valve stack (78) is operably connected to the spool (72) for controlling the oil flow path through the control orifice (76).

The system (100) comprises of a motor (20), a coupler (40) and a slip clutch (60). The motor (20) is operably connected to the plunger shaft (62) to drive the spool (72) for adjusting the damping. The spool (72) is withdrawn or inserted by providing rotary motion of the motor (20). The coupler (40) is operably connected to the motor (20).

The slip clutch (60) is operably connected between the hollow piston rod (70) and the motor (20) by means of the coupler (40). The slip clutch (60) has two plates (not shown) just like an automobile clutch. When the torque provided increases the set or design parameters of the slip clutch (60), the plates start to slip one over the other. The slip clutch (60) is adapted to move the spool (72) for any one of opening and closing the multi-stage disc/valve stack (78) to change the oil flow path. The slip clutch (60) prevents overloading of the motor (20). The slip clutch (60) also avoids the motor (20) from failing or burning out.
In an operation, the user selects any one of the hard setting and the soft setting by using an electric switch (not shown) provided on a dash board (not shown) of a vehicle (not shown). When the user selects the hard setting (refer figure 2), the plunger shaft (62) is moved by the motor (20) through the slip clutch (60). The plunger shaft (62) drives the spool (72) in order to move the spool (72) fully in a bottom position. When the spool (72) is fully in the bottom position, the spool (72) blocks the oil flow by closing the multi-stage disc/valve stack (78). The oil flow in the shock absorber (80) follows a path with high resistance to provide damping force. When the user selects the soft setting (refer figure 3), the spool (72) is withdrawn in order to open the multi-stage disc/valve stack (78). A part of the oil is made to flow through least resistive path. Accordingly, with change in the oil flow path, the damping forces drop to achieve comfortable ride quality.

In an embodiment, the system (100) is adjusted by the user for the hard setting during running the vehicle in sports mode, on smooth road / highway and for the soft setting during running the vehicle on rough roads. However, it may be evident to those skilled in the art that other settings for damping effect are also possible using the system (100).

Advantages of the invention:

1. The system (100) provides more comfort while travelling in city conditions and better handling at highway drives.

2. The system (100) is provided with user selectable settings for adjusting the damping.

3. The system (100) prevents overloading and burning out of the motor (20) while in operation.

The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and approaches are overcome by the present invention described in the present embodiment. Detailed descriptions of the preferred embodiment are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure, or matter. The embodiments of the invention as described above and the methods disclosed herein will suggest further modification and alterations to those skilled in the art. Such further modifications and alterations may be made without departing from the spirit and scope of the invention.

,CLAIMS:We claim:

1. A system (100) for load adaptive damping in a shock absorber (80) to adjust damping based on user’s selection, the shock absorber (80) having a hollow piston rod (70), a plunger shaft (62) accommodated within the hollow piston rod (70), a spool (72) operably connected to the plunger shaft (62), a piston assembly (74), a control orifice (76) for allowing an oil flow there through and a multi-stage disc/valve stack (78) operably connected to the spool (72) for controlling the oil flow path through the control orifice (76), the system (100) comprising:
a motor (20) being operably connected to the plunger shaft (62) to drive the spool (72) for adjusting the damping;
a coupler (40) being operably connected to the motor (20); and
a slip clutch (60) being operably connected between the hollow piston rod (70) and the motor (20) by means of the coupler (40), the slip clutch (60) being adapted to move the spool (72) for any one of opening and closing the multi-stage disc/valve stack (78) to change the oil flow path thereby varying damping forces while preventing overloading and burning out of the motor (20),
wherein, when the user selects a hard setting of the shock absorber (80), the slip clutch (60) moves the spool (72) to close the multi-stage disc/valve stack (78) and when the user selects a soft setting, the slip clutch (60) moves the spool (72) to open the multi-stage disc/valve stack (78).

2. The system (100) as claimed in claim 1, wherein the plunger shaft (62) is moved by the motor (20) through the slip clutch (60) to change the oil flow path to achieve varying damping forces as per user’s selection.

3. The system (100) as claimed in claim 1, wherein the user selects any one of the hard setting and the soft setting by using an electric switch configured on a dash board of a vehicle.

4. The system (100) as claimed in claim 1 is adjusted by the user for the hard setting during running the vehicle in sports mode, on smooth road / highway and for the soft setting during running the vehicle on rough roads.