DESC:TECHNICAL FIELD
Embodiments of the present disclosure generally relates to vibration damper in a vehicle. More particularly, but not exclusively, relates to vibration damp arrangement in a steering system in vehicle or automobile.

BACKGROUND OF THE DISCLOSURE
Vehicle is a dynamic system which exhibits vibration in response to excitation inputs. The vehicle vibration response determines the magnitude and direction of vibration imposed on the passenger compartment and determines the passenger’s perception of the vehicle. To understand ride, it is required to understand, ride excitation sources, basic mechanics of vehicle vibration response, and human perception and tolerance of vibrations. The roughness in a road is the deviation in elevation seen by a vehicle as it moves along the road. The roughness acts as a vertical displacement input to the wheels, thus exciting ride vibrations. Steering wheel system is connected to front wheel of the vehicle, thus road vibration are transferred to steering wheel. At some extent vibration transferred through road inputs are dampened by hydraulic oil in steering rack and pinion mechanism and at universal joint. Steering rack and pinion mechanism is mounted through brake on vehicle body, thus engine vibration are also transferred till the steering wheel. Lateral force variations may arise from non uniformities in the tire, but be readily related to lateral run out effects in the wheel or hub components. They tend to be independent of speed, thus measurements of the force magnitudes at low speed are also valid for high speed. First-order lateral variations in the tires or wheels, or in the way in which they are mounted, will cause wobble. These will affect the dynamic balance of the assembly. The wobble in the wheel may contribute a minor lateral force variation, but may also result in radial and tractive force variations comparable to the effect of oviality because the wheel is elliptical in the vertical plane. Higher-order lateral variations are predominantly important in the tire only. Wheel variations are substantially absorbed by the tire. These sources could potentially cause steering wheel vibrations. In light of forgoing discussion, it is necessary to develop a system for observing vibrations in the steering system of the vehicle to overcome the limitations stated above.

OBJECTS OF THE DISCLOSURE
One object of the present disclosure is to provide vibration damper in a steering wheel system.

Another object of the present disclosure is to provide vibration damper system in a steering axle system.

SUMMARY OF THE DISCLOSURE
The shortcomings of the prior art are overcome and additional advantages are provided through the provision of the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the disclosure.

In one embodiment, the present disclosure relates a vibration damper for a steering wheel system of a vehicle. The vibration damper comprising, a twin cylinder unit comprising an outer tube and an inner tube, with a space formed between the outer tube and the inner tube to act as a channel for a hydraulic fluid flow. A first end of the outer tube is slidably connected to a steering column of the steering wheel system and a second end of the outer tube is connected to a universal joint of the steering wheel system. A piston is connected to a steering wheel main shaft of the steering wheel system and placed inside the inner tube to form a chamber in the inner tube. The chamber is filled with the hydraulic fluid; and a base valve connected to outer tube and placed inside the inner tube and placed opposite to the piston. The base valve is configured with at least one orifice axially for allowing the hydraulic fluid flow between the chamber and the channel to dampen the vibrations caused in the steering wheel system of the vehicle.

In one embodiment, a seal is provided at the first end of the outer tube, in between the outer tube and the inner tube for preventing hydraulic fluid flow from the channel to the inner tube.

In one embodiment, the steering wheel main shaft passes through the seal at the first end of the outer tube.

In one embodiment, the piston is connected to the inner tube using a key and key-way mechanism.

In one embodiment, the base valve is provided with a helical spring at the end facing the piston to prevent impact resistance to the base valve from the piston.

In one embodiment the base valve is connected to the outer tube at the second end of the outer tube
using at least one mechanism selected from a group comprising welding, brazing, and a fastener.

In one embodiment, the present disclosure relates a vibration damper system for a steering axle of a vehicle. The vibration damper system comprises a piston slidably mounted around the steering axle and inside an outer tube of the steering axle, wherein an annulus gap is formed between the piston and the outer tube; sealing means mounted inside the outer tube and at either sides of the piston to configure closed compartments on either side of the piston; wherein the closed compartments are filled with hydraulic fluid; wherein the hydraulic fluid flows between the compartments through the annulus gap in response to vibrations caused in the steering axle to dampen the vibrations caused in the steering axle of the vehicle.

In one embodiment, the outer tube is configured with at least one oil filling channel and at least one sealing screw for filling hydraulic fluid and for sealing the hydraulic fluid leakage from the closed compartments.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Figure 1 shows sectional view of a steering shaft assembly comprising a vibration damping arrangement according to an embodiment of the present disclosure.

Figure 2 shows magnified view of portion indicated by X in figure 1.

Figure 3 shows piston at Top Dead Centre (TDC) according to an embodiment of the present disclosure.

Figure 4 shows piston at Bottom Dead Centre (BDC) according to an embodiment of the present disclosure.

Figure 5 shows movement of inner tube and outer tube due to linear movement of the universal joint according to an embodiment of the present disclosure.

Figure 6 shows a perspective view of a steering axle system incorporated with a vibration damper system according to an embodiment of the present disclosure.

Figure 7 shows a magnified view of portion indicated by “Y” in figure 6 according to an embodiment of the present disclosure.

Figure 8 shows schematic of hydraulic fluid flow between the compartments A and B according to an embodiment of the present disclosure.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION OF THE DISCLOSURE
The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristic of the disclosure, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.

It is to be noted at this point that all of the above described components, whether alone or in any combination, are claimed as being essential to the disclosure, in particular the details depicted in the drawings and reference numerals in the drawings are as given below.

Reference will now be made to the exemplary embodiments of the disclosure, as illustrated in the accompanying drawings. Wherever possible, same numerals will be used to refer to the same or like parts.

Referral Numerals
Referral Numerals Description
1 Universal joint
2 Base valve
2a Orifice in the base valve
3 Piston
4 Steering wheel main shaft
5 Seal
6 Outer tube
6a First end of the outer tube
6b Second end of the outer tube
7 Inner tube
7a Chamber
8 Channel for hydraulic fluid flow
9 Key and Keyway mechanism
10 Helical Spring
11 Twin cylinder unit
12 Rack
12a Annulus gap
13 Sealing means
14 Steering column
15 Outer tube in the steering axle
15a Filling channel
15b Sealing screw
16 Pinion
17 Tie-rod
20 Vibration Damper system in steering axle
21 Piston in the steering axle system
22 Steering axle
A and B Compartments
100 Vibration damper in steering shaft assembly

The present disclosure provides for a vibration damper. The vibration damper comprises a twin cylinder unit and a base valve. The twin cylinder unit comprises an inner tube and an outer tube enclosing the inner tube such that a channel is created between the inner tube and the outer tube for hydraulic fluid flow. A second end of the outer tube is integrated with a steering upper universal joint and a first end of the outer tube is connected to a steering column. A seal is placed at connecting joint between the outer tube and a steering wheel main shaft. A base valve is connected to the universal joint and placed inside the outer tube. One end of the steering wheel main shaft is connected to a piston and other end of the steering wheel main shaft is connected to the steering wheel. The piston is connected to the inner tube with a mechanism such as but not limited to key and keyway mechanism and spline mechanism. The outer tube and the inner tube slides vertically in the key and key-way joint as per universal joint displacement according to the vibrations from the road conditions, during which resistance from the hydraulic fluid present in the chamber provides resistance to the vibrations by flowing between the chambers and the channel.

In one embodiment, the present disclosure relates a vibration damper system for a steering axle of a vehicle. The vibration damper system comprises a piston slidably mounted around the steering axle and inside an outer tube of the steering axle, wherein an annulus gap is formed between the piston and the outer tube; sealing means mounted inside the outer tube and at either sides of the piston to configure closed compartments on either side of the piston; wherein the closed compartments are filled with hydraulic fluid; wherein the hydraulic fluid flows between the compartments through the annulus gap in response to vibrations caused in the steering axle to dampen the vibrations caused in the steering axle of the vehicle. In one embodiment, the outer tube is configured with at least one oil filling channel and at least one sealing screw for filling hydraulic fluid and for sealing the hydraulic fluid leakage from the closed compartments.

Figure 1 illustrates a sectional view of a steering shaft assembly comprising a vibration damper (100) according to an embodiment of the present disclosure. The vibration damper (100) comprises a twin cylinder unit (11) and a base valve (2). The twin cylinder unit (11) comprises an inner tube (7) and an outer tube (6) enclosing the inner tube (7) such that a channel (8) is created between the inner tube (7) and the outer tube (6) for hydraulic fluid flow. A second end (6b) of the outer tube (6) is integrated with the steering upper universal joint (1) and a first end (6a) of the outer tube (6) is connected to a steering column (14) of the steering shaft assembly. A seal (5) is provided at connecting joint between the outer tube (6), a steering wheel main shaft (4) and the inner tube at the first end (6a) of the outer tube (6) for preventing hydraulic fluid flow from the channel (8) to the inner tube (7). In one embodiment, the steering wheel main shaft (4) passes through the seal (5) at the first end (6a) of the outer tube (6). A base valve (2) is connected to outer tube (6) and placed inside the outer tube (6). The base valve (2) is configured with at least one orifice (2a) for allowing flow of the hydraulic fluid to and from the chamber (7a) and the channel (8). In one embodiment, the base valve (2) is provided with a helical spring (10) at the end which faces a piston (3) to prevent impact resistance to the base valve (2) from the piston (3). In one embodiment, the base valve (2) is connected to the outer tube (6) at the second end (6b) of the outer tube (6) using at least one mechanism selected from a group comprising welding, brazing, and a fastener. One end of the steering wheel main shaft (4) is connected to the piston (3) and other end of the steering wheel main shaft (4) is connected to the steering wheel. The piston (3) is connected to the inner tube (7) using a mechanism such as but not limited to key and keyway mechanism (9) or spline mechanism. Also, the piston (3) is connected to a steering wheel main shaft (4) of a steering wheel system and placed inside the inner tube (7) to form a chamber (7a) in the inner tube (7). The chamber (7a) is filled with the hydraulic fluid. The outer tube (6) and the inner tube (7) slides vertically in the key and keyway mechanism (9), as per displacement of the universal joint (1) due to road inputs as shown in figures 3-5.

During steering, the steering rotational torque is transferred to achieve wheel turns and is accomplished by the steering rod rotation which is transferred from the piston (3) to the twin cylinder unit (11) connected to the upper universal joint (1). The base valve (2) is fitted at bottom of inner tube (7) which separates contact of the inner tube (7) and the outer tube (6). In one embodiment, the base valve (2) is fixed to the inside of the outer tube (6). The piston (3) is attached to the end of the steering wheel main shaft (4) which works against pressure of the hydraulic fluid in the inner tube (7). As the universal joint (1) travels up and down (as shown in Figure 5) due to undulations on the road surface, the hydraulic fluid present in the chamber (7a) is forced through tiny holes, called orifices, between the piston (3) and the base valve (2) as shown in Figure 2 to enter the channel (8). Primary purpose of the vibration damper is to control vertical movement of twin cylinder unit (11). This is accomplished by turning kinetic energy of cylinder movement through the hydraulic fluid.

The steering wheel main shaft (4) passes through a seal (5) at the upper end of the twin cylinder unit (11). The seal (5) keeps the hydraulic fluid inside the twin cylinder unit (11) and does not allow the contamination. The key and key way mechanism (9) keeps the piston (3) in line with the inner tube (7) and allows the steering wheel main shaft (4) to move freely inside the inner tube (7).

The orifices (2a) in the base valve (2) let only a small amount of hydraulic fluid from the chamber (7a) to the channel (8). The orifices (2a) are tuned such that, the orifice (2a) slows down movement of the twin cylinder unit (11) by transfer of the hydraulic oil/fluid from the inner tube (7) to the outer tube (6) and vice versa, which in turn slows down vertical movement of the assembly of inner tube (7) and the outer tube (6) and thereby reduces the vibrations. The twin cylinder unit (11) along with the base valve (2) and hydraulic fluid acts as a velocity sensitive hydraulic damper. Faster the universal joint movement, the more resistance the vibration damper provides. Thus, the twin cylinder unit (11) absorbers and adjust to road conditions.

Figure 3 illustrates movement of piston (3) at Top Dead Centre (TDC) according to an embodiment of the present disclosure. During movement of the piston (3) to the TDC position, the hydraulic fluid flow is inside through the orifice (2a) to the inner tube (7).

Figure 4 illustrates movement of piston (3) at Bottom Dead Centre (BDC) according to an embodiment of the present disclosure. During movement of the piston (3) to the BDC position, the hydraulic fluid flow is outside through the orifice (2a) to the outer tube (6).

Figure 5 illustrates movement of the inner tube (7) and the outer tube (6) due to linear movement of the universal joint (1) according to an embodiment of the present disclosure. The universal joint (1) is moved linearly due to road inputs such as undulations on the road surface. The linear movement of the universal joint (1) is transferred to the outer tube (6). As the outer tube (6) and the inner tube (7) are joined through a key-keyway mechanism (9) or spline joints, the inner tube (7) is slidable inside the outer tube (7) linearly along the key-keyway mechanism (9) or spline joint in D1 and D2 directions depending on the road inputs.

Figure 6 illustrates a perspective view of a steering axle system incorporated with a vibration damper system (20) according to an embodiment of the present disclosure. The vibration damper system (20) consists of a piston (21) mounted coaxially and slidably on the rack (12), more specifically around the steering axle (22) an inside an outer tube (15). On either side of the piston (21), oil seals or sealing means (13) are mounted and are coaxially mounted to the rack (12) forming to closed variable volume compartments “A” and “B” (as shown in Figure 7) which completely seals the oil coming out of compartment “A” and “B” forming a closed hydraulic circuit. The piston (21) does not have any seals and partially seals the compartments “A” and “B”. The vibration damper system (20) consists of an oil filling channel (15a) and sealing screws (15b) on the outer tube (15) to fill fluid and seal it into the sealed enclosure. In an exemplary embodiment, the outer tube (15) is configured with at least one oil filling channel (15a) and at least one sealing screw (15b) for filling hydraulic fluid and for sealing the hydraulic fluid leakage from the closed compartments (A and B).

When the steering wheel is turned normally, the pinion (16) rotates which moves the rack (12), thereby moving the piston (21) with relation to the outer tube (15). Based on the direction of the steering rotation, oil passes from the compartment “A” to “B” and vice versa along the annulus gap (12a) of the piston (21). But during a sudden impact on wheels there will be sudden lateral input transferred from the wheels of the vehicle to tie-rod (17) which is further transferred to rack (12) and then to the pinion (16) and steering wheel in absence of the vibration damper system (20). In presence of the vibration damper system (20), the sudden lateral input is only transferred till the tie rod (17) and thereafter it is arrested by the vibration damper system (20) avoiding further transfer to the rack (12) and the pinion (16) and to the steering rod (not shown). The dampening happens at the compartments “A” and “B” due to sudden hydraulic fluid rush from one compartment to another compartment through small peripheral area, i.e. annulus gap (12a) between the piston (21) and the outer tube (15). Thus, there is a sudden resistance generated on the rack (12) due to flow of the hydraulic fluid from one compartment to the other compartment and the impact force or the lateral force is slowed down. Thereby, avoiding any further impact or vibration to the steering wheel and then to driver or user.

Figure 7 illustrates a magnified view of portion indicated by “Y” in figure 6 according to an embodiment of the present disclosure. The figure clearly illustrates the compartment A and compartment B and the flow of the hydraulic fluid from the compartment A and the compartment B due to vibrations caused in the wheels (not shown) which will be transferred from the tie rods (17) to the vibration damper system (20).

Figure 8 illustrates a schematic of hydraulic fluid flow between the compartments A and B according to an embodiment of the present disclosure.

Advantages
In one embodiment, the vibration damper as disclosed in the present disclosure improves ride index and comfort quality.

In one embodiment of the present disclosure, the vibration damper reduces damp, health hazardous frequencies which create considerable resonance between hand and shoulder of the user. Thereby improves overall health of the user/rider and reduces jerks and vibrations.

In one embodiment, the vibration damper improves measurement quality as accuracy of axis alignment increases.

In one embodiment, the vibration damper absorbs the vibration and sudden lateral force due to road input and thereby increasing driver comfort.

In one embodiment, design of twin cylinder unit solves many of ride control problems by adding a low pressure charge in the outer tube. Pressure of the outer tube varies, depending on the amount of fluid in the outer tube. Thus it serves a several important functions to improve the ride control characteristics of a shock.

In one embodiment, the vibration damper as disclosed in the present disclosure improves ride index and comfort quality.

In one embodiment of the present disclosure, the vibration damper reduces damp, health hazardous frequencies which create considerable resonance between hand and shoulder of the user. Thereby improves overall health of the user/rider and reduces jerks and vibrations.

In one embodiment, the vibration damper improves measurement quality as accuracy of axis alignment increases.

In one embodiment, the vibration damper absorbs the vibration and sudden lateral force due to road input and thereby increasing driver comfort.

The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purpose of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included in so far as they come within the scope of the invention as claimed or the equivalents thereof.

Equivalents
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

,CLAIMS:We claim:
1. A vibration damper (100) for a steering wheel system of a vehicle, the vibration damper (100) comprising:
a twin cylinder unit (11) comprising an outer tube (6) and an inner tube (7), with a space formed between the outer tube (6) and the inner tube (7) to act as a channel (8) for a hydraulic fluid flow, wherein a first end (6a) of the outer tube (6) is slidably connected to steering column (14) of the steering wheel system and a second end (6b) of the outer tube (6) is connected to an universal joint (1) of the steering wheel system;
a piston (3) connected to a steering wheel main shaft (4) of a steering wheel system and placed inside the inner tube (7) to form a chamber (7a) in the inner tube (7), wherein the chamber (7a) is filled with the hydraulic fluid; and
a base valve (2) connected to outer tube and placed inside the inner tube (7) and placed opposite to the piston (3), wherein the base valve (2) is configured with at least one orifice (2a) axially for allowing the hydraulic fluid flow between the chamber (7a) and the channel (8) to dampen the vibrations caused in the steering wheel system of the vehicle.

2. The vibration damper (100) as claimed in claim 1, wherein a seal (5) is provided at the first end (6a) of the outer tube (6), in between the outer tube (6) and the inner tube (7) for preventing hydraulic fluid flow from the channel (8) to the inner tube (7).

3. The vibration damper (100) as claimed in claim 1, wherein the steering wheel main shaft (4) passes through the seal (5) at the first end (6a) of the outer tube (6).

4. The vibration damper (100) as claimed in claim 1, wherein the piston (3) is connected to the inner tube (7) using a key and key-way mechanism (9).

5. The vibration damper (100) as claimed in claim 1, wherein the base valve (2) is provided with a helical spring (2a) at the end facing the piston (3) to prevent impact resistance to the base valve (2) from the piston (3).

6. The vibration damper (100) as claimed in claim 1, wherein the base valve (2) is connected to the outer tube (6) at the second end (6b) of the outer tube (6) using at least one mechanism selected from a group comprising welding, brazing, and a fastener.

7. A vibration damper system (20) for a steering axle (22) of a vehicle, the vibration damper system (20) comprises:
a piston (21) slidably mounted around the steering axle (22) and inside an outer tube (15) of the steering axle (22), wherein an annulus gap (12a) is formed between the piston (21) and the outer tube (15);
sealing means (13) mounted inside the outer tube (15) and at either sides of the piston (21) to configure closed compartments (A and B) on either side of the piston (21); wherein the closed compartments (A and B) are filled with hydraulic fluid;
wherein the hydraulic fluid flows between the compartments (A and B) through the annulus gap (12a) in response to vibrations caused in the steering axle (22) to dampen the vibrations caused in the steering axle (22) of the vehicle.

8. The vibration damper system (20) as claimed in claim 7, wherein the outer tube (15) is configured with at least one oil filling channel (15a) and at least one sealing screw (15b) for filling hydraulic fluid and for sealing the hydraulic fluid leakage from the closed compartments (A and B).