AUTOMOTIVE SEAT SLIDER WITH BI-DIRECTIONAL LOCKING SYSTEM
Field of the Invention
The present invention relates to a slider assembly for automotive seats and more
particularly to a bi-directional locking system of the slider assembly.
Background of the Invention
Automotives generally require slider assemblies or sliders that provide not only a back and forth movement of the seat but also a locking of the seat, at a desired position by means of a locking system. The slider assembly also acts as a safety critical component, in the event of collision, by withstanding the impact forces that act on the seat, without resulting in any major deformation or breakage.
A typical locking system of the slider assembly comprises upper and lower rails, said lower rails provided with a series of openings/slots, mounted on the floor of an automotive. The seat cushion of an occupant of an automotive mounted on the upper rail of the slider assembly and the occupant adjusts the seat position by sliding after unlocking it with the help of a towel bar/handle and on reaching the desired position the handle is released to provide a locking of the slider assembly.
The locking is effected by a series of lock pins that are provided on the upper rail, which are permitted to slide over the bottom rail during unlock position and these pins are further arranged to enter the openings/slots of the lower rail, to lock the slider assembly at a desired position. Whenever, the locking of the slider assembly is effected, the two lock pins are engaged with the lower rail simultaneously to make one complete locking. In other words, one lock pin prevents the sliding of the slider assembly in forward direction and the other lock pin prevents sliding in rearward direction.
Accordingly, in the locked condition, only one lock pin prevents sliding in the forward direction and the other lock pin prevents sliding in the rearward direction. Thereby, the lock-breakdown strength of the slider assembly is limited by the strength of only one lock/lock pin.
Further, the locking system is mounted on top of the upper rail making the height of the whole assembly very large and making it difficult to accommodate in circumstances where space is a constraint.
Typical seat sliders are complicated and expansive due to having more number of parts and thus making assembly difficult to manufacture and load bearing capacity remains limited.
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Objects of the Invention
The primary object of the present invention is to provide a robust, flexible, high-strength and fine-pitch slider assembly, for automotive seats, with reduced number of simple components that are easy to assemble, reliable and cost effective.
An object of the present invention is to provide a seat slider assembly for automotive seats with a bi-directional, differential and multiple-pin locking system for an effective locking.
Another object of the present invention is to provide a slider assembly for automotive seats with a single or multiple locking at a single locked position.
Yet another object of present invention is to provide a slider assembly for automotive seats to augment the strength without enhancing the strength/thickness of rail.
Further object of present invention is to provide a slider assembly for automotive seats to enhance the occupant safety by absorbing more impact energy.
Still another object of present invention is to provide a compact slider assembly for automotive seats, to ease problems of space constraints.
Summary of the Invention
The present invention provides a slider assembly for automotive seats for implementing a bidirectional, differential and multiple-pin locking system. The slider assembly comprises an upper rail on which the seating system is mounted. A lower rail relatively positioned to the upper rail, said lower rail is fitted to the floor of automotive. The upper rail is movable relative to the lower rail in a longitudinal direction. A plurality of spring-biased lock pins disposed on the upper rail, said lock pins further disposed to axially slide on the lower rail, under the biasing action of the spring. A plurality of openings/slots provided on the lower rail with intervening spaces. A towel bar is connected to the rails to enable sliding and locking of the slider assembly. The lock pins, which are disposed with axial movement, effect locking by passing through the openings/slots of the lower rail. During the locking of the slider assembly, the lock pin is pushed through an opening/slot in the lower rail to make a locking and prevents the upper rail to slide either in the forward or rearward direction. Once the locking is effected one lock pin prevents sliding of the upper rail in both directions i.e. both in forward and backward directions. The locking pins spaced with desired intervening gaps, said gaps are generally not equal but proportional to the intervening gaps of the openings/slots of the lower rail As a result, at one locked position, one or more number of lock pin(s) pass through one or more (respectably) opening(s) on the lower rail, and
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a plurality of (one or more) lock pins remain seated over the lower rail, as they do not find any corresponding opening/slot to get into in that position. In another locked position, a different set of lock pins (one or more) find openings/slots in the lower rail and makes locking. This arrangement of differential sets of lock pins finding openings/slots in the lower rail at different positions of locking enables a finer pitch (less than the pitch of the openings/slots in the lower rail).
Brief description of the accompanied diagrams
Fig 1 is a perspective view of automotive seat assembly with seat slider assembly.
Fig 2 is a perspective view of a seat slider assembly of automotive seat of Fig 1 with seat removed for clear view of seat slider assembly.
Fig 3 depicts the locking arrangement of the rail assembly along with a towel bar assembly.
Fig 4 is an enlarged view of the locking arrangement of the slider assembly of the present invention.
Fig 5 is an enlarged bottom view of locking arrangement of the slider assembly of the present invention depicting the locking condition of the pins.
Fig 6 is a side view of slider assembly of the present invention depicting the unlocked condition of the pins.
Fig 7 is a sectional view of the locking arrangement in locking condition of the slider assembly of the present invention.
Fig 8 is a side view of the locking system of the slider assembly of the present invention depicting pins with rectangular/square cross section housed in a bracket.
Fig 9 is a side view of the locking system of the slider assembly of the present invention depicting a bracket with variable angle.
Fig 10 is a side view of the locking system of the slider assembly of the present invention depicting an embodiment of the locking system implemented by a leaf spring.
Fig 11 is a side view of the locking system of the slider assembly of the present invention depicting an embodiment of the locking system with lock pin operating springs mounted over the upper rail.
Fig 12 is a side view of the locking system of the slider assembly of the present invention depicting an embodiment of the locking system with an external leaf spring.
Fig 13 is a schematic expression depicting single row locking system of the slider assembly of the present invention with two pins effecting a single lock mechanism.
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Fig 14 is a schematic expression depicting a single row locking system of the slider assembly of the present invention with three pins effecting a single lock mechanism.
Fig 15 is a schematic expression depicting a single row locking system of the slider assembly of the present invention with three pins effecting a single lock mechanism. Although it represents the same concept as that in fig 15, here the relative arrangement of the pins and slots are different.
Fig 16 is a schematic expression depicting a single row locking system of the slider assembly of the present invention with four pins effecting a double lock mechanism.
Fig 17 is a schematic expression depicting a single row locking arrangement of the slider assembly of the present invention with six pins effecting a double lock mechanism.
Fig 18 is a schematic expression depicting a two-row locking arrangement of the slider assembly of the present invention with four pins disposed in two rows effecting a
double lock mechanism.
Fig 19 is a schematic expression depicting a two-row locking arrangement of the slider
assembly of the present invention with six pins effecting a triple lock mechanism.
Fig 20 is a schematic expression depicting a three-row locking arrangement of the slider assembly of the present invention with nine pins effecting a triple lock mechanism.
Fig 21 is a schematic expression depicting a locking arrangement of the slider assembly
of the present invention depicting a single pin implementing a single lock.
Fig 22 is a schematic expression depicting a locking arrangement of the slider assembly
of the present invention with a simultaneous engagement of all the pins, especially with
double pin effecting a double lock.
Fig 23 is a schematic expression depicting a locking arrangement of the slider assembly
of the present invention with a simultaneous engagement of all the pins, especially with
three pins providing a triple lock.
Detailed description of the invention
Accordingly, the present invention provides a slider assembly for automotive seats and
more particularly to a bi-directional locking system of the slider assembly. The seat
slider assembly of the present invention is provided with a bi-directional, differential
and multiple-pin locking system for an effective locking of the seat at a pre-determined
location. The embodiments of the present invention are described by referring to the
accompanied diagrams.
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Initially, referring to Figs 1-2, provide a perspective view of an automotive seat with a seat slider assembly. The seat slider assembly is mounted on the floor 2 of an automotive. Typically, the slider assembly comprises a pair of rails 5 running parallel to each other. A towel bar 4 is disposed by connecting the parallel rails 5. A seat cushion 3 mounted on top of the rails 5, said rails provide a lateral support to the seat cushion 3. The rails 5 comprise an upper rail 17 and a lower rail 14. The lower rail 14, which is stationery, is fitted to the floor 2 of the automotive and the upper rail 17, disposed on the lower rail 14, to travel/slide along the length in forward and rearward directions in relation to the lower rail 14. The locking mechanism, which is here in after described in detail, can be unlocked by means of the towel bar 4 to reposition the seat cushion 3 at various desire positions.
Now by referring to Fig 3, is an upper view of the slider assembly of the present invention with the upper rail 17 is slid along the length of the rails to provide a clear inner view of the lower rail 14. The locking assembly 20 of the present invention is mounted on the upper rail 17, through the holes 18. Lifting plate 21 of locking assembly 20 is connected with the towel bar assembly 4 through hook towel bar 9. Towel bar assembly 4 includes tube towel bar 6, rod towel bar 7 and hook towel bar 9. Towel bar mounting bracket 12 is mounted on the top of upper rail 17. Other end 13 (clearly shown in Fig 4) supports the rod towel bar 7 enabling it to rotate about its axis. Tube towel bar 6 is welded with the rod towel bar 7 at the point 8. Hook towel bar 9 is joined at the end 10 (of the tube towel bar 6). Other end 11 (of the hook towel bar 9) is engaged with the lifting plate 21 (of the lock mechanism 20) so that the lifting plate is operated by the means of the towel bar 6.
The implementation of locking system of the present invention is now described by referring to Fig 4, 5 and 6, wherein the lock assembly 20 is mounted on the upper rail 17. Initially, the implementation of locking system is described by using a two-pin single lock mechanism for a sliding assembly.
Lock assembly 20 comprises lock pins 24, a housing bracket 28, a lifting plate 21, a U-bracket 30, a spring 33 and a nut and bolt 32. U-bracket 30 and housing bracket 28 are mounted on the upper rail 17 at the holes 18. Lock pins 24 are mounted on the upper rail 17 at the holes 19. The lifting plate 21 is mounted on the housing bracket 28 with the nut and bolt 32 such that it can rotate about the bolt 32. Spring 33 is mounted on the bolt 32 and it holds the lifting plate 21 in its position. The end 11 (of the hook towel bar 9) passes through the slot 22 of the lifting plate 21. When the occupant of the vehicle
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activates the tube towel bar 6, the slot 22 (of the lifting plate 21) is pushed down enabling unlocking of the slider assembly. Other end 23 (of the lifting plate 21) goes below the heads 25 of the lock pins 24. When the end 22 (of the lifting plate 21) is pushed down (by the hook towel bar 9), the end 23 moves up and lifts the lock pin 24 to effect unlocking of the slider mechanism.
Figure 7 depicts a sectional view of lock mechanism 20 depicting the locking condition of the lock pins 24 during operation. The lock pins 24 are biased with a spring 34, on release of the towel bar, pushes the lock pins 24 down towards the lower rail 14. The lower rail 14 is provided with a plurality of openings/slots 15 and a plurality of intervening webs/lands 16 at regular interval along its length. In this configuration the pin 24(b) goes through a slot 15 of the lower rail 14 (as it finds a slot 15 in this position) and makes a locking. However, in this position, the lock pin 24(a) does not find any slot 15 on the lower rail 14 and sits on the top of the land/web 16 (of the lower rail 14). A taper angle is provided at the end 26 of the lock pin 24 to enable easy entry of the lock pin 24 into the slot and to reduce/eliminate the play along the length of rail. The lower end 26 of lock pin 24 is tapered for easy entry of the pin(s) 24 to the slot(s) 15, U-bracket 30 holds the middle part 27 and guides it for axial sliding, the spring 34 pushes a pin 24 down through the U-bracket 30. The two ends 31 (of the U-bracket 30) are mounted with the upper rail 17 at the holes 18. As mentioned earlier, the U-bracket 30, the housing bracket 28 and the upper rail 17 are joined together at holes 31,29 and 18 respectively.
The above description is the detail implementation of one of the embodiments of the present invention showing the locking arrangement with two pins forming a single lock. It is also within the scope of the present invention to implement locking arrangement as described hereinafter by referring to Fig 8- 23.
In another embodiment of the present invention, the locking system wherein a plurality of dimensions and shapes of the locking elements are described. Now by referring to Fig 8, which depicts locking pins with rectangular/square cross sections, that are adapted to effect the locking of the slider assembly.
Lock pins 24 are modified with rectangular/square cross-section at their high load bearing area/region, to enable an enhanced area of contact thereby reducing the level of stress concentration at the contact point with the lands 16 on the lower rail 14. By adapting the locking arrangement with rectangular/square lock pins 24 as shown in Fig 8, the second moment of inertia of the lock pins 24 (in locking region) get increased
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and there by increasing the lock break down strength. By the virtue of these two effects,
the load bearing capacity of the mechanism gets enhanced.
In yet another embodiment of the present invention, the construction of bracket
assembly for housing the locking elements is described in conjunction with Fig 9. The
bracket 30 is modified by providing a draft angle 0 as shown in Fig 9. This
arrangement provides an enhanced load bearing capacity to the locking arrangement of
the present invention. It is also observed here that the shape of the bracket 30 is
provided with a draft angle (0) to increase the capacity of the bracket 30 to support
higher load on locking pin.
In further embodiment of the present invention, the locking assembly of the present
invention is implemented with an internal leaf spring as depicted in Fig 10.
In this arrangement, the compression biasing springs are replaced with a set of leaf
springs 34, resulting in a very compact locking assembly.
In yet another embodiment of the present invention, the locking assembly comprising
lock pin operating springs that are mounted outside and over the upper rail (Fig 11). In
this construction, the lock pin 24 is provided with biasing compression springs 34,
which are externally mounted over the upper rail 17 and pushing the top of the lock
pins 24.
In still another embodiment of the present invention, the locking assembly is
implemented by an external leaf spring as depicted in Fig 12. In this arrangement,
compression springs are replaced with a set of leaf springs 34. By implementing this
locking arrangement, the leaf spring 34 is mounted externally over the upper rail 17
with this upper rail height can be reduced and this can enable using the mechanism
where space is constrained.
In the present invention, the locking system is implemented by considering the
differences between the pitch of openings/slots on the lower rail 'Pr' and that of the
lock-pins 'Pi', resulting in the following locking arrangements, which have been
designated as cases 1, 2 & 3.
Case 1: If the pitch distance of the lock pins 'pi' is different than that of the
slots/openings on the lower rail ‘Pi’ then a suitable arrangement of multiple number of
pins (two or more) results in a mechanism pitch, which is finer than that of the slots on
the lower rail. This case type has been described under the concept types A and B
below.
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Case 2: If there is only one pin then the mechanism pitch will be the same as that of the
openings/slots on the lower rail i.e. ‘Pr’ This case type has been described under the
concept type C (1) below.
Case 3: If there are more than one lock pin but the pitch distance between the pins ‘Pl is same as that of the openings/slots on the lower rail 'Pr' (i.e. Pl = Pr) then also the
pitch of the mechanism will be that of the lower rail i.e. ‘Pr’. However, this condition
will result in simultaneous multi-locking resulting in higher strengths. This case type
has been described under the concept types C (2) and C (3) below.
The locks are bi-directional in nature since in a locked condition each lock prevents
movements both in the forward and rearward direction.
The mechanism is flexible to give a wide variety of arrangements virtually resulting in
any pitch distance desired from the mechanism.
It is possible to have simultaneous multi locking resulting in higher strength of the
mechanism.
To meet a variety of typical customer needs, a number of concepts have been
developed by implementing the above described design principle.
As an exemplary embodiment, a list of these concepts has been briefly illustrated under
three types: Type A (Figures 13 through 17), Type B (Figures 18 through 20), Type C
(Figures 21 through 23), and Type D (Figure 13 through 17).
Type A: Single Row Locking
1. Two pins, single lock implementation
The locking arrangement of this type is described by referring to Fig 1-7 along with the
schematic diagram in Fig 13.
Now, by specifically referring to Fig 13, in this Implementation of the invention the
pitch of the slots 'Pr' = 2 and pitch of the lock pins ‘Pl’ = 3, and number of lock pins are
two. In this configuration one lock pin 24(a) gets into a slot 15and makes a locking
where as the other lock pin 24(b) cannot get into any slot and remains seated over the
web/land 16 of the lower rail. In this arrangement for every relative movement of "1"
between the upper rail 17 and the lower rail 14 (referring fig 7) the mechanism get
locked alternatively by the two lock pins 24(a) and 24(b), Hence the pitch of the
mechanism becomes "1".
In this locking arrangement of the present invention, the total number pins used for
locking is two and the total number of lock pins 24 getting engaged during a locking
position is one. The mechanism pitch is one.
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2. Three pins, single lock, fine pitch
In this Implementation (Fig 14) of the invention pitch of the slots 'Pr' = 3 and pitch of the lock pins ‘Pl’ = 4, and the number of lock pins is 3. In this configuration one lock pin 24(a) gets into a slot 15 and makes a locking where as the other two lock pins 24(b) and 24(c) cannot get into any slot and remains seated over the Web/land 16 of the lower rail.
In this arrangement for every relative movement of Pr = 3, between the upper rail 17 and the lower rail 14 (ref fig 7), the mechanism gets locked thrice at regular /equal interval (i.e. Pr = 1). Accordingly, if the value of Pr is maintained same as that in
concept A(l) i.e. "2", then the mechanism pitch will work out to 2/3 resulting in a
refinement in the mechanism pitch with out compromising strength. In this locking arrangement of the present invention, the total number pins used for locking is three and the total number of lock pins 24 getting engaged during a locking position is one.
3. Three pins, single lock, compact
In this Implementation (Fig 15) of the invention pitch of the slots 'Pr' = 3 and pitch of the lock pins 6Pj? = 2, and the number of lock pins is 3. In this configuration one lock pin 24(a) gets into a slot 15(a) and makes a locking where as the other lock pins 24(b) and 24(c) cannot get into any slot and remains seated over the web/land 16 of the lower rail.
In this locking arrangement of the present invention, the total number of lock pins 24 used for locking is three and the total number of lock pins 24 getting engaged during a locking position is one. Similar to concept in A(2) in this arrangement also for every relative movement of Pr between the two rails the mechanism get locked thrice resulting to mechanism pitch = Pr/3. However for a given value of Pi one can have higher value of Pr resulting in increased width of land. This implementation also gives the compact arrangement of locking mechanism.
4. Four pins, double lock
In this Implementation of the invention (Fig 16) pitch of the slots ‘Pr’ = 2 and pitch of the lock pins 'Pl’ = 1, and the number of lock pins is 4. In this configuration two lock pins 24(a) and 24(c) gets into two slots 15(a) and 15(b) respectively and makes two independent locking where as the other two lock pins 24(b) and 24(d) can not get into
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any slot 15 and remains seated over the webs/lands 16(a) and 16(b) respectively of the lower rail.
In this locking arrangement of the present invention, the total number of lock pins 24 is four and the total number of lock pins 24 get engaged simultaneously during a locked condition is two. In this arrangement, for every relative movement of "1" between the upper rail 17 and lower rail 14 (ref fig 7), the mechanism get locked alternatively and thereby the mechanism pitch remains “1”
By implementing the locking arrangement of this type a compact locking arrangement of the Lock-Pins in a limited space is achieved, where two pins are simultaneously engaged in a lock position and shall have double the strength of one pin locking of same configuration. Further, the optimum size of the lock pins is restricted by the space available and there by limiting the Lock Breakdown force.
5. Six pins, double lock, fine pitch
In this Implementation of the invention (Fig 17) pitch of the slots 'Pr' = 3 and pitch of the lock pins 'Pi' = 2, and the number of lock pins is 6. In this configuration two lock pins 24(a) and 24(d) gets into a slots 15(a) and 15(c) and make two locking where as the other lock pins 24(b), 24(c), 24(e), and 24(f) can not get into any slot and remains seated over the webs/lands 16 of the lower rail.
In this locking arrangement of the present invention, the total number of lock pins 24 used for locking is six and the total number of lock pins 24 getting engaged simultaneously during a locked condition is two. In this arrangement, for every relative movement of "1" between the upper rail 17 and lower rail 14 (ref fig 7), the mechanism get locked alternatively and thereby the mechanism pitch remains "1".
Type B: Multi Row Locking
1. Two rows, four pins, double lock
The locking arrangement of the present invention can also be implemented in a multi-row arrangement as shown in (Fig 18). Here, 15 represents slots/openings on the lower rail 14, 24 represents the lock pins mounted on the upper rail 17 and 16 represents webs/lands between two consecutive slots/opening 15. In this Implementation of the invention pitch of the slots 'Pr' = 2 and pitch of the lock pins 'Pi' = 2 in any row of the lock pins, and the number of lock pins 24 is 4. In this configuration, lock pins 24 of row one Rl gets into a slots 15 and make a locking where as the lock pins 24 of the other row R2 cannot get into any slot and remains seated on top of the webs/lands 16 of the lower rail.
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In this implementation, the total number of lock pins 24 that are used for locking is four and the number of lock pins 24 get engaged in a locked position is two. In this arrangement, for every relative movement of "1" between the upper rail 17 and lower rail 14 (ref fig 7), the mechanism get locked alternatively and thereby the mechanism pitch remains "1".
2. Two rows, six pins, triple lock
In this Implementation (Fig 19) of the invention pitch of the slots ‘Pr’ = 2 and pitch of the lock pins ‘Pl’ = 2 in any row of lock pins 24, and the number of lock pins 24 is 6. In this configuration three lock pins 24 of row one Rl get into three slots 15 and make three independent locking where as the balanced three lock pins 24 of the other row R2 can not get into any slot and remains seated on top of the webs/lands 16 of the lower rail.
In this locking arrangement, the total number of lock pins 24 that are used for locking is six and the number of lock pins 24 get engaged in a locked position is three. In this arrangement, for every relative movement of "1" between the upper rail 17 and lower rail 14 (ref fig 7), the mechanism get locked alternatively and thereby the mechanism pitch remains "1".
3. Three rows, nine pins, triple lock
In this locking arrangement (Fig 20) of the present invention pitch of the slots 'Pr' = 3
and pitch of the lock pins 'Pi' = 2 in any row of lock pins 24, and the number of lock
pins 24 is nine. In this configuration three lock pins 24 one from each row get into two
slots 15 and make three independent locking where as the balance lock pins 24 can not
get into any slot and remains seated on top of the webs/lands 24 lower rail 14.
In this arrangement, for every relative movement of "1" between the upper rail 17 and
lower rail 14 (ref fig 7), the mechanism get locked alternatively and thereby the
mechanism pitch remains "1".
Type C: Simultaneous engagement of all pins
1. Single pin, single lock (Fig 21)
In this Implementation of the invention pitch of the slots ‘Pr’ = 1 and the number of
lock pin 24 is 1. In this configuration lock pin 24 gets into a slot 15 and makes a
locking. In this locking arrangement, the total number of lock pin 24 used is one and
the total number of lock pin 24 that are used for a locking engagement is also one. In
this arrangement, for every relative movement of Pr (the pitch distance of the slots 15
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on the lower rail) between the upper rail 17 and lower rail 14 (ref fig 7), the mechanism get locked alternatively and thereby the mechanism pitch remains as Pr = 1.
2. Double pins, double lock (Fig 22)
In this Implementation of the invention pitch of the slots ‘Pr’ = 1, and the number of lock pins 24 is 2. In this configuration both the lock pins 24 get into two slots 15 and make two independent locking. In this locking arrangement, the total number of lock pins 24 used are two and the number of lock pins 24 for a locking engagement is also 2. In this arrangement, for every relative movement of Pr (the pitch distance of the slots 15 on the lower rail) between the upper rail 17 and lower rail 14 (ref fig 7), the mechanism get locked alternatively and thereby the mechanism pitch remains as Pr = 1.
3. Triple pins, triple lock (Fig 23)
In this locking arrangement of the present invention, pitch of the slots ‘Pr’ = 1, and the number of lock pins 24 is three. In this configuration all the three lock pins 24 get into three slots 15 simultaneously and make three independent locking. During the implementation of this locking arrangement, total number of lock pins 24 used is three and total number of lock pins 24 get engaged is also three. In this arrangement, for every relative movement of Pr (the pitch distance of the slots 15 on the lower rail) between the upper rail 17 and lower rail 14 (ref fig 7), the mechanism get locked alternatively and thereby the mechanism pitch remains as Pr = 1.
Advantages of the invention
1. The current invention of bidirectional differential multi locking mechanism has the
potential of providing single as well as multiple locking at one locked position i.e.
one or more number of pins are simultaneously engaged with the corresponding
number of slots in the lower rail and with this arrangement the strength of the
mechanism becomes multiple of the number of locks that got engaged and the
strength of one individual lock. This is achieved by diverting the total load (a
mechanism) equally to the individual locks.
2. The locking mechanism is mounted centrally with respect to both the upper rail and
lower rail. Accordingly application of any force on the seating will not bring in any
undesired moment of twisting either on the upper rail or on the lower rail.
3. Locking mechanism is placed underneath the upper rail and is sandwiched between
its profiles. This enables keeping the height of the mechanism less and making it
very compact.
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4. Formations of the rails are such that the upper rail slides inside a channel of the
lower rail and to ensure smooth sliding the two rails are separated by bearings from
both top and bottom.
5. The lower rail is intended to be mounted on the floor of the vehicle and a seating
system is to be mounted on top of the upper rail.
6. For a particular combination of material property, thickness and cross-section for
lower rail, upper rail and lock pin there is a maximum lock break down strength that
the mechanism can offer for a single lock condition (i.e. one lock pin is engaged
with one slot in the lower rail).
7. The slider assembly has an internal locking system using one lock at a time. Due to
one lock, the slider mechanism has better utilization of material recourse.
8. As the slider mechanism implants a bidirectional differential multi locking
mechanism, in the event of application of an excessive load (more than the designed
load capacity) there will be a failure in the locking that got engaged before land
however after some deformation in that locking components, the second set of locks
will get engaged. In other words, in the event of failure this system will absorb
double or more than double (in the case of more than one set of stand by locking) in
pack energy.
Dated: 11th day of February 2006.

A