FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION (See Section 10; rule 13)
TITLE OF THE INVENTION
Improved Lift Axle Assembly
APPLICANTS
TATA MOTORS LIMITED, an Indian company
having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
INVENTOR/S
Amit K Gupta
Sandip R Mane
Sunil K Agarwal
Ganesh kale
All Indian national
of TATA MOTORS LIMITED an Indian company
having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.

Improved Lift Axle Assembly
Field of invention
The present invention relates to lift axle for a vehicle and more particularly it relates to an improved lift axle assembly for a vehicles.
Background of Invention
Generally the lift axle assembly is provided on heavy commercial vehicles
such as cargo trucks, tippers and tractors for extra load bearing axle when
required.
When load on vehicle is less the lift axle assembly of vehicles lifts the axle
thus avoids unnecessary contact of tyre with road. The lifting of tyre to avoid
unnecessary contact with the road reduces rolling resistance and thus helps in
improving fuel economy, unnecessary tyre wear and hence operating cost of
the vehicle
The axles of vehicles are lifted with the help of inflating and depleting the
bellows provided therein. Said bellows are the most important and active
parts in the lift axle asseblies. The installation of said bellows plays major role
in determining the life of said bellows and thus operating cost of the vehicles.
Generally the base and top plate of the said bellows should preferably remain
parallel to each other.
In majority of the lift axle, the lift bellow plates are not parallel to each other
which is not suitable for better life of the lift bellow. Also location of the lift
bellows are near to the ground which increases the chances of failure of said
bellows. The the structures of the lift axle should be stronger enough to
sustain the loads which increases the unnecessary weight on the vehicle
decreasing the payload capacity of the vehicle.
US 5403031, the lift bellow is placed between upper arm and lower arm, in
rebound condition of axle , the position of lower arm and upper arm comes

nearer to the ground, as this lift bellow is mounted between the said lower and upper arms, the lift below also comes near to the ground , which reduces the ground clearance at lift bellows.
The connection arrangement of lower and upper arm at hanger is having a sheet metal bracket which is connected to said arms with integral bush and sleeve clamped with bolts. The said sheet metal bracket is compressed due to tightening of the bolt which develops huge preload in the bolt in the axial direction. The bolt also experiences the sheer force due to push and pull of the said arms and cause the failure of the said bolt.
In lift axle, apart from the axle assembly with tyres, lift axle structure is the major weight contributing part in the lift axle system. Thus reduction of structural weight can result in benefits such as reduction in operating cost, improvement in pay load capacity. The structural rigidity lift axle plays major role in maintaining position of the axle and also steering geometry lift axle.
Object of the invention
The main object of the present invention is to provide an improved lift axle assembly.
Another object of the present invention is to provide an improved lift axle assembly wherein the base plate and top plate of bellows are parallel to each other.
Another object of the present invention is to provide an improved lift axle assembly wherein the light casted member is used as joineries for joining LH and RH hanger.

Another object of the present invention is to provide an improved lift axle assembly wherein the said casted bracket provided to act as pivot mounting for the arms.
Another object of the present invention is to provide an improved lift axle assembly wherein the lower and upper arms are pivoted at casted member with help of metallic sleeve which is simply supported on the casted member.
Statement of invention
An improved lift axle assembly comprises; LH and RH long members , at least one hanger member vertically mounted on each side of said long members, an axle seat member provided on each side of long member, a pair of lower arm and upper arm pivotally connected to each said axle seat member and said said hanger member, a main bellow mounted on each said seat members, axle beam mounted on said axle seats member, wherein a lift bellow vertically sandwitched between lower and upper lift bellow mounting brackets provided on side of each long member, said lower lift below mounting brackets pivotally connected to integral arm integral to lower arm, a cross member is provided perpendicular to said long member, at least one link member is pivotally connected to said cross member and lower lift below mounting bracket on each side of long member, at least one casted member connected to bottom end of each said hanger and said cross member, a locking plate mounted on said casting member, metallic sleeve provided inside said casted member; and said metallic sleeve, casted member and hanger are held together with the help of bolting arrangement.
An improved lift axle assembly, in accordance with present invention, wherein said lift bellow is vertically arranged between said lower and upper lift below mounting bracket.

An improved lift axle assembly , in accordance with present invention, wherein
said lower and upper lift bellow mounting bracket are vertically arranged and
connected to said long members.
An improved lift axle assembly, in accordance with present invention, wherein
said link members are arranged perpedicular to said cross member to
maintain parallelogram.
An improved lift axle assembly, in accordance with present invention, wherein
said link member having ball joint at both end pivotally mounted to said lower
lift below mounting bracket and said cross member,
An improved lift axle assembly, in accordance with present invention, wherein said casted member is provided on each side of long member.
An Improved iift axle assembly, in accordance with present invention, wherein said casted member is connected to lower end of said hanger and said cross member.
An improved lift axle assembly, in accordance with present invention, wherein said casted member having at least two metallic sleeve arrangement for connecting said lower and upper arm.
An improved lift axle assembly, in accordance with present invention, wherein said fower and upper arm is pivoted at said casted member and focked with the help of said metallic sleeve lock plate arrangement and sleeve collar.
Summary of the Invention
In accordance with the present invention, an improved lift axle assembly comprises; LH and RH long members 01, two hangers 02 vertically mounted on said long members 01,two casted member 15 mounted on bottom of hanger 02, two axle seat member 03 of which one is connected with casted

member 15 with lower arm 08 and upper arm 09 in-between, at least two main bellows 04 mounted one on each said seat members 03, at least two lift bellows 05 vertically mounted, lift bellows mounting brackets 06 for mounting of said lift bellows 05, main below mounting bracket 07 for said main bellows 04 to mount on to said long member 01, a lower arm 08 and upper arm 09 pivotally connected to casted member 15 and seat members 03, lower lift below mounting bracket 10 pivotally connected onto integral arm 20 to lower arm 08, axle beam 11 mounted on said axle seats member 03, cross member 13 is provided perpendicular to said long member 01, wherein at least one link member 14 is provided on cross member 13 on each side connected to said lower lift below mounting bracket 10, casted member 15 connected with said cross member 13, locking plate 18 is connected to said casting bracket 15, metallic sleeve 19 provided inside said casted member 15, said metallic sleeve 19 , casted member 15 and hanger 02 are held together with the help of the nut 17 and bolt 16.
Brief Description of the Drawing
Figure 01 shows side view of the lift axle assembly.
Figure-02 shows the Front view of the lift axle assembly.
Figure-03 shows the Top view of the lift axle assembly.
Figure-04 shows the front isometric view of the lift axle assembly.
Figure-05 shows the rearisometric view of the lift axle assembly.
Figure-06 shows the details of casted member for joining cross member with LH and RH hangers.

Figure-07 shows the isometric view of the casted member of lift axle assembly.
Figure-08 shows the sectional view of the pivotal joint of said arms of lift axle, with supported metallic sleeve arrangement provided on said casted member.
Figure-09 shows the paralellogram arrangement of lift axle system
Detailed description of invention
Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting the same.
In accordance with the present invention, an improved lift axle assembly comprises; LH and RH long members 01, two hangers 02 vertically mounted on said long members 01,two casted member 15 mounted on bottom of hanger 02, two axle seat member 03 of which one is connected with casted member 15 with lower arm 08 and upper arm 09 in'between, at least two main bellows 4 mounted one on each said seat members 03, at least two lift bellows 05 vertically mounted, lift bellows mounting brackets 06 for mounting of said lift bellows 05, main below mounting bracket 07 for said main bellows 04 to mount on to said long member 01, a lower arm 08 and upper arm 09 pivotally connected to casted member 15 and seat members 03, lower lift below mounting bracket 10 pivotally connected to an integral arm 20 to lower arm 08, axle beam 11 mounted on said axle seats member 03, cross member 13 is provided perpendicular to said long member 01, wherein at least one link member 14 is provided on cross member 13 on each side connected to said lower lift below mounting bracket 10, casted member 15 connected with said cross member 13, locking plate 18 is connected to said casting bracket 15,

metallic sleeve 19 provided inside said casted member 15, said metallic sleeve 19 , casted member 15 and hanger 02 are held together with the help of the nut 17 and bolt 16.
Now Referring in figure-01 and 02, the said long member(s) 01 are horizontally provided along the axis of the vehicle. At least one hanger member 02 is provided on LH and RH side of said long members 01. The upper end of the said hanger 02 is rigidly connected to the said long member 01. The lower end of the said hanger 02 is connected to said lower arm 08 and upper arm 09 with the help of casted member 15 in-between as mounting means. The said main bellows 04 are mounted on said seat member 03 and upper main bellow mounting bracket 07 are mounted on long members 01 such that said main bellows 04 are sandwiched between said seat member 03 and upper main bellow mounting bracket 07. One end of the said lower arm 08 and upper arm
09 are connected to said casted bracket 15 other end is connected to seat
member 03.
The said lift bellows 05 are mounted on said lower lift bellow mounting bracket
10 and upper lift bellow mounting bracket 06 which are connected to long
members 01 and the arrangement is such that said lift bellows 05 are
sandwiched between said lower lift bellow mounting bracket 10 and upper lift
bellow mounting bracket 06. The lift bellows 05 are vertically arranged or
sandwiched between upper lift bellow mounting bracket 06 and lower lift
bellow mounting bracket 10.
Casted member 15 with link bush and sleeve arrangement are provided wherein the said sleeve is simply supported on said casted member. The axial and rotational movement of said sleeve 19 are arrested with the help of sleeve having extended collar and lock plate 18 respectively.
Referring to the figure-03 which is the top view of the axle assembly. The said lower arm 08 and upper arm 09 are disposed parallel to the long member 01.

The said cross member 13 and axle beam 11 are perpendicular to the said long member 01 and vehicle centre line.
When vehicle moves in forward direction the pulling force generated travels through lift axle to two sets of lower arm 08 and/or upper arm 09 and thus finally to axle,
Now referring to the figure-04 and 05, said casted member 15 is connected to lower end of the said hanger 02. The said cross member 13 is provided for connecting both the said casted members 15 mounted on the said hangers 02 provided on either sides of the long members for making the complete rigid structure to take care of lateral loads coming on to the lift axle assembly. The flanges 15a and 15b are provided on said casted member 15 for connecting to said cross member 13. The other end 15c of said casted member 15 is connected to lower end of said hanger 02. The said lower arm 08 and upper arm 09 are pivoted onto the said casted member 15.
The said axle seat member 03 is connected to the said hangers 02 with the help of lower arm 08 and upper arm 09 in-between them. The said lower arm 08 and upper arm 09 transfers pulling forces coming from said hangers 02 and lifting forces generated from lift bellow 05, to the axle. Also a part of the road reaction and forces coming from ground via axle is transferred to the assembly structure through said lower arm 08 and upper arm 09. The said lower arm 08 and upper arm 09 are having bushes on the pivot ends for reducing the forces coming from the ground.
At least one axle seat members 03 is provided on the LH and RH sides of lift axles. The said axle seat members 03 is connected to casted member 15 with help of said lower arm 08 and upper arm 09 on either sides of the lift axle assembly.

The said axle seats 03 are mounted on said axle beam 11. The said axle seat members 03 are provided for mounting said main bellows 04.
The said main bellow 04 is vertically mounted onto the said axle seat member 03. The top plate of said main bellow 04 is mounted on the upper main bellow mounting bracket 07 which is mounted on the long member 01.
The said main bellow 04 mounted on the axle seat member 03 transfers major part of the axle reaction to the said long members 01 and thus to frame of the vehicle.
The said lower arm 08 is having the integral arm 20. The front end of said integral arm 20 of the said lower arm 08 is pivotally connected to said lower lift bellow mounting bracket 10. The said integral arm 20 is pivotally connected at the bottom side of the said lower lift bellow mounting bracket 10. The said cross member 13 is having link member 14 disposed perpedicular to said cross member 13 and parallel to the said integral arm 20 of the lower arm 08. One end of link member 14 is pivotally connected to the upper side of the said lower lift bellow mounting bracket 10 and other end is pivotally connected to the said cross member 13. The arrangement of providing said integral arm 20 of the lower arm 08, lower lift bellow mounting bracket 10 , link member 14 and the line joining between the pivot point of link member 14 at cross member and pivot point of lower arm at casted member, forms the parallelogram at the lift bellow 05.
The said link member 14 having ball joints at the both ends which allows swiveling of said lower link 08 in lateral direction which eventually eliminates immediate loading of the parallelogram mechanism at the lift bellow 05 mounting area.

The said lift bellow 05 is vertically mounted on the lower lift bellow mounting bracket 10. The top plate of the said lift bellow 05 is mounted on the said upper lift bellow mounting bracket 06. The said upper lift bellow mounting bracket 06 is connected to the said long member 01. The pivot point of said lower arm 08 on the said casted member 15 and the pivot point of said link member 14 on the said cross member 13 dwells on the vertical line and said vertical line joining said pivot points remains perpendicular long members.
The said bottom plate of lift bellow 05 is mounted on the said lower lift bellow mounting bracket 10. In the said parallelogram arrangement, the said mounting bracket 10 remains vertical and thus perpendicular to the said long member 01 throughout the rotating movement of the said lower arm 08. The bottom plate of said lift bellow 05 is mounted on the horizontal face of the said lower lift bellow mounting bracket 10 which thus remains parallel to top and bottom faces of said long members.
The top plate of said lift bellow 05 is mounted on the bottom face of the said upper lift bellow mounting bracket 06. The said bottom face of the said upper lift bellow mounting bracket 06 remains parallel to the bottom face of said long member which makes the top plate and bottom plate of said lift bellow 05 to remain parallel to each other throughout the angular articulation of the lifting mechanism.
When the wheels are in contact with ground, said lift bellow 05 is in deplated condition and main bellow 4 is in inflated condition. In order to lift the axle the lift below inflates and main bellow 4 deflates, this generates the downward force on the said lower lift bellow mounting bracket 10 which enables to pivot the said lower link 08 about the pivot point on the said casted member 15 and thus lifting the axle from the ground.
The said link member 14 at the lift bellow 05 keeps the top plate and bottom plate of lift bellow 05 parallel to each other.

Now referring to figure-06 which shows the sectional view of the pivotal joints of said lower arm 08 and upper arm 09 with casted member 15. The rubber bush is provided at each end of the lower arm 08 and upper arm 09 at each pivot on said casted bracket 15 and said axle seat member 03.
At pivot, the said lower arm 08 and upper arm 09 and casted member 15 is assembled with the help of metallic sleeve 19 with the collar. The said metallic sleeve 19, casted member 15 and hanger 2 are held together with the help of the bolting arrangement having nut 17 and bolt 16. After tightening of bolt 16, the collar of the said metallic sleeve 19 restricts the axial movement of the said metallic sleeve 19 and hence avoids the axial movement with respect to the casted member 15. The locking plate 18 is mounted on the said casting bracket 15. The flat surfaces of the collar restricts the rotating movement of the said metafile sleeve 19 as rotating movement is restricted with the help of the said locking plate 18. The said metallic sleeve 19 is supported onto the side flanges of casting member 15, thus takes all the loads coming from the said lower 08 and upper arm 09 gets transferred to said casted member 15 thereby preventing the failure of said bolt 16, which otherwise may cause to shear the said bolt 16.
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 as they come within the scope of the invention as claimed or the equivalents thereof.

We claim
1. An improved lift axle assembly comprises; LH and RH long members , at least one hanger member vertically mounted on each side of said long members, an axle seat member provided on each side of long member, a pair of tower arm and upper arm pivotally connected to each said axle seat member and said said hanger member, a main bellow mounted on each said seat members, axle beam mounted on said axle seats member, wherein a lift bellow vertically sandwitched between lower and upper lift bellow mounting brackets provided on side of each long member, said lower lift below mounting brackets pivotally connected to integral arm integral to lower arm, a cross member is provided perpendicular to said long member, at least one link member is pivotally connected to said cross member and lower lift below mounting bracket on each side of long member, at least one casted member connected to bottom end of each said hanger and said cross member, a locking plate mounted on said casting member, a metallic sleeve provided inside said casted member; and said metallic sleeve, casted member and hanger are held together with the help of bolting arrangement.
2. An improved lift axle assembly as claimed in claim 1, wherein said lift bellow is vertically arranged between said lower and upper lift below mounting bracket.
3. An improved lift axle assembly as claimed in claim 1, wherein said lower and upper lift bellow mounting bracket are vertically arranged and connected to said long members.
4. An improved lift axle assembly as claimed in claim 1, wherein said link members are arranged perpedicular to said cross member to maintain parallelogram.
5. An improved lift axle assembly as claimed in claim 1, wherein said link member having ball joint at both end pivotally mounted to said lower lift below mounting bracket and said cross member.

6. An improved lift axle assembly as claimed in claim 1, wherein said casted member is provided on each side of long member.
7. An improved lift axle assembly as claimed in claim 1, wherein said casted member is connected to lower end of said hanger and said cross member.
8. An improved lift axle assembly as claimed in claim 1, wherein said casted member having at least two metallic sleeve arrangement for connecting said lower and upper arm.
9. An improved lift axle assembly as claimed in claim 1, wherein said lower and upper arm is pivoted at said casted member and locked with the help of said metallic sleeve lock plate arrangement and sleeve collar.
10. An improved lift axle assembly as herein substantially described with reference to accompanying drawings.