GB2542138A

GB2542138A - Seat locking mechanism

Info

Publication number: GB2542138A
Application number: GB1515902.3A
Authority: GB
Inventors: Beck Adam
Original assignee: Mobility Networks (holdings) Ltd
Current assignee: Mobility Networks (holdings) Ltd
Priority date: 2015-09-08
Filing date: 2015-09-08
Publication date: 2017-03-15
Also published as: GB201515902D0

Abstract

Seat locking mechanism 1 for a vehicle comprises a plurality of locking elements 9, 10, 11, 12, 13 engaging and locking with a mounting 2 (e.g. rail mounting) on the vehicle floor. The locking elements 9-13 are each arranged to rotate between locked and unlocked positions and are engaged with one another (e.g. via partial gears) so that rotation of one locking element causes simultaneous rotation of all locking elements. Each locking element comprises a locking portion 21 arranged to engage the mounting in the locked position thereby securing the seat to the vehicle. The locking elements may be linearly arranged. The locking elements may be engaged with one another via teeth and rotate and lift simultaneously together when moving into locked position. A resilient strip (27, figure 5) may bias the locking elements into locked position.

Description

SEAT LOCKING MECHANISM

This invention relates to a seat locking mechanism, and more particularly to a mechanism that allows removal or position adjustment of a seat within a vehicle.

In the interior of a vehicle it is known to provide rails on the floor in which a mechanism secured to a seat can engage to lock the seat to the rail. These mechanisms can slide along the length of the rail allowing back and forth position adjustment of the seat. These mechanisms can also disengage from the rail allowing removal of the seat from the vehicle. An example of a prior art mechanism is shown in GB2347619. A problem with this mechanism is that it is possible to engage the mechanism within the floor rail without properly locking the mechanism to the rail, meaning a seat could accidentally be left unsecure. A further problem is the plates which engage with the rail can rattle and vibrate particularly when the mechanism is unlocked. It is therefore desirable to provide a locking mechanism which relieves these problems.

Accordingly the present invention provides a seat locking mechanism for a vehicle comprising a plurality of locking elements arranged to engage and lock with a mounting provided on the floor of the vehicle, wherein the locking elements are each arranged to rotate between locked and unlocked positions and are engaged with one another so that rotation of one locking element causes simultaneous rotation of all locking elements, and wherein each locking element comprises a locking portion that is arranged to engage the mounting in the locked position thereby securing the seat to the vehicle.

The seat locking mechanism may further comprise a body wherein the locking elements may extend through the body and each locking element may comprise a cam which engages the body and causes the locking element to move axially when rotated. The locking elements may each comprise two opposing cam surfaces which locate the locking elements relative to the body.

The seat locking mechanism may further comprise a biasing means which biases the locking elements into the locked position. The biasing means may be a resilient strip which is deformed by rotation of the locking elements when moved into the unlocked position.

The locking elements may be arranged linearly. One of the locking elements may comprise a handle arranged to rotate the locking element. The locking elements may be engaged with one another via teeth. When moving from the unlocked to the locked position the locking elements may rotate and lift simultaneously.

The seat locking mechanism may further comprise a mounting arranged to be secured to the floor of a vehicle, wherein the mounting may comprise two sides and a base which define a slot along the length of the mounting and wherein both sides may be bent towards one another to form a lip.

The locking portion may be a disk with protruding lugs which may be arranged to enter the slot in the mounting in the unlocked position and to engage behind the lip when rotated into the locked position. The mounting may define indentations formed at regular interval along the length of the slot and the disk may comprise a profile shaped to engage indentations in the locked position.

The seat locking mechanism may be arranged to attach to a frame of the seat for the vehicle. The seat locking mechanism may further comprise a wheel arranged to engage the floor of the vehicle when the frame is in a tipped back position. The wheel may be arranged to lift the locking mechanism out of the mounting when the locking mechanism is unlocked and the wheel engages the floor. The vehicle may comprise a car, a bus, a train, an aeroplane, a boat or any other means of seated transport.

The locking mechanism may further comprise, in any combination, any one or more of the features of the preferred embodiments of the invention which will now be described, by way of example only, with reference to the accompanying drawings.

Figure 1 shows the internals of a seat locking mechanism and rail according to an embodiment of the present invention;

Figure 2 shows the seat locking mechanism and rail of figure 1 with the locking mechanism engaged in the rail;

Figure 3 shows the seat locking mechanism and rail of figures 1 & 2 with the locking mechanism in the locked position in the rail;

Figure 4 shows an external view of the seat locking mechanism shown in figures 1 to 3;

Figure 5 shows a section view through the top of the seat locking mechanism shown in figures 1 to 4;

Figure 6 shows an end view of the seat locking mechanism shown in figure 1 to 5 connected to the frame of a seat;

Figure 7 shows a side view of the seat locking mechanism shown in figures 1 to 6 connected to the frame of a seat;

Figure 8 shows the internals of a seat locking mechanism and rail according to another embodiment of the present invention;

Figure 9 shows a side view of the seat locking mechanism shown in figure 8 connected to the frame of a seat; and

Figure 10 shows a section view through the top of the seat locking mechanism shown in figure 9 through the section A-A.

Referring to figure 1, a locking mechanism 1 is shown aligned above a mounting rail 2. The rail 2 is fastened securely to the interior floor of a vehicle. The rail has a base 4 and two sides 5, 6 which extend the length of the rail. The sides angle inwards forming an acute angle with the base 4. The top edge of each side is bent over towards the opposite side and parallel with the base forming a lip 7. The sides and base define a slot 3 which extends the length of the rail. In the edge of the lip 7 a series of indentations 8 are formed at regular intervals along the length of the slot 3. The indentations 8 are semi-circular and are formed on both sides of the slot such that the indentations align on both sides and provide a series of circular openings in the top of the rail 2 connected by the slot 3.

The locking mechanism 1 comprises a series of five inline locking elements 9, 10, 11, 12 and 13. Each locking element comprises a shaft 14 which extends the length of the locking element along a central axis of the locking element. The shafts of the locking elements are in a parallel arrangement relative to each other and arranged vertically in use. The shafts 10 are equally spaced along the length of the locking mechanism and can each rotate about their respective central axis. The locking elements are located within a block 15. The block 15 is rectangular and defines a series of holes 35 which pass from openings on the top side of the block to openings on the bottom side of the block. The holes 35 are space linearly at regular intervals. The block 15 is formed in two halves with a central split line 15a which splits the holes 35 in half down their length. Each hole 35 has a cylindrical recess 34 on the upper and lower surface. Each recess extends along the length of the hole from the opening into the surface of the block, widening the diameter of the hole 35. When assembled, the locking elements are positioned within the holes and extend through the block 15 with one end of each locking element protruding on each side of the block 15. The block 15 may be made of a lightweight material such as injection moulded plastic that is resistant to caustic substances which are uses to clean vehicle floors such as ambulances.

Each locking element has a partial gear 16, 17, 18, 19 & 20 fixed at an upper end of the shaft 14 which engages the neighbouring gear of the next locking element. The partial gears have teeth which only surround a part of the circumference. The partial gear 16 of the first locking element 9 comprises a handle 33 and three teeth which engage two teeth on the gear 17 of the next locking element 10. The remaining partial gears 17, 18, 19 & 20 have two teeth on their circumference which engage with the previous gear, and two flat sides separate a second group of three teeth on the circumference which engage with the neighbouring gear. The locking elements are therefore all engaged via the gears so that rotation of one element causes rotation of the other elements simultaneously, with each gear rotating in the opposite direction to the gear(s) adjacent to it.

Each locking element comprises a locking disk at the opposite end of the shaft 14 to the gear end, i.e. the lower end in use. All locking disks are the same. The locking disk 21 comprises a circular shaped central portion 21a with two lugs 22 extending beyond the circumference of the circular central portion on opposing sides of the disk. The lugs 22 are arranged to pass through the slot 3 when aligned with the slot but when the locking element is rotated into a locked position the lugs are arranged to engage behind the lip 7 on the rail 2. The circular central portion 21a comprises a chamfered collar 21b which tapers the diameter of the disk 21 into the shaft 14. The collar 21b is chamfered to help locate the circular central portion 21a of the locking disk 21 in one of the circular openings on the top of the rail 2.

Each locking element comprises a shaft 14 which is the same for all locking elements. The shaft 14 comprises an upper 23 and lower 24 cam positioned on either side of the block 15. The upper and lower cams fit within the cylindrical recesses formed in the upper and lower surfaces of the block 15. Each cam has a profiled cam surface 25, 26 which engages with the block 15 and the profile is shaped so that rotation of the shaft causes the cams to react against the block and move the shaft axially upwards through the block as indicated in Figure 3. A portion of the block is located between the upper and lower profiled cam surfaces 25, 26 which oppose one another. The cams 24 and 25 have matching profiles so that the shaft remains located by the block between the cam surfaces and only rotation of the shaft will cause axial movement. The cams in adjacent holes have alternate profiles so that all the shafts 14 move upwards when moving to the locked position, since the shafts rotate in alternate directions. A spring 27 in the form of a deformable strip is provided which extends along the flat sides of the partial gears 16, 17, 18, 19, 20. The spring is arranged to bias the locking elements into the locked position. The spring presses the flat sides of the gears into an offset, zigzag, arrangement from a position in which the flat sides of the gears are aligned causing the locking elements to rotate in alternating directions, as shown in Figure 5. The spring can deform into a straighter shape when sufficient force is applied through the gears from the handle 33.

Two mounting plates 28 and 29 sandwich and secure the two halves of the block together. The mounting plates are bolted to a frame 30 which is fitted between the seat support 31 and foot 32 of a chair. The lever for unlocking the mechanism extends out between the two mounting plates 28, 29.

In use two locking mechanisms 1 are fitted either side of the rear of a seat and two rails are secured to the interior floor of a vehicle. To fit the seat, the locking disks 21 on the locking mechanisms are aligned with the circular openings in the top of the rail. The handle 33 on each mechanism is rotated against the spring 27 which rotates all the gears simultaneously, the gears rotating in alternate directions. The handle is rotated until it is in line with the gears 16, 17, 18, 19, 20 and block 15 as shown in figure 1. With the handle aligned the lugs 22 on the locking disk 21 are all rotated in line with the slot 3 allowing the locking disks on each mechanism to be positioned down into their respective rail 2. With the chair in the desired position along the rail 2 the handles are released, in each mechanism the spring returns the handle and the gears into the original offset, zigzagged, position which also causes the locking disks 21 to rotate and lugs 22 to rotate under the lip 7 of the rail. Also the cams 23, 24 cause the shafts 14 to simultaneously lift as the handle is released which lifts the locking disks clamping the lip 7 of the rail between the locking disk lug 22 and the block 15 preventing vertical movement between the rail and the mechanism. As the locking disks lift, the chamfered collar 21b guides the central portion 21a of the locking disk 21 into one of the circular openings in the top of the rail. The collar engages within one of the circular openings which prevents the chair slipping forward or back along the rail.

To remove a chair from the vehicle the handles of the locking mechanisms are held in line with the body causing the gears in each mechanism to rotate the locking elements so that the lugs on the locking disk are aligned with the slot. As the handle is brought in line with the body the cams 24, 25 rotate forcing the shafts 14 axially downwards which releases the clamp on the rail lip between the lugs 22 and the block 15, and also lowers the central portion of the lifting disks out of the circular openings in the rail. At this point the seat may either be adjusted forward or back along the rail or removed from the rail by pulling up on the rear of the seat.

Advantageously the spring always biases the mechanism into the locked position preventing a chair accidently being left unsecured when fitted to the rail.

It will be appreciated the connecting mechanism can have two or more locking elements and the number of locking elements depends on the application and the security of the connection required.

In an alternative embodiment of the invention the portion of the locking element which engages with the mounting may have a different form, for example the portion may comprise a course thread which engages with the lip on the rail. In a further alternative the portion may be a simple bar which engages under the lip on the rail.

In a further embodiment of the invention a longer connecting mechanism with more connecting elements may be used to mount a seat to a vehicle with a single connecting mechanism attached to a single leg of the chair. This arrangement may save overall weight and space.

In a further embodiment of the invention, the gears which engage the locking elements may be complete gears with teeth which surround the shaft and the biasing means may be a spring which is attached to the handle biasing it into an offset position.

Figures 8-10 shows a locking mechanism 35 according to a further embodiment of the invention in which the locking mechanism functions in the same way as the embodiment of the invention shown in figures 1-7. Additionally a wheel 36 is provided which is attached between the two mounting plates 35, 40, by an axle 37. The mounting plates 35,36 each comprise a lug portion 38 which supports the axle 37 and separates the wheel 36 from the locking elements 39. In figure 9 the locking mechanism is shown fitted to the frame 41 of a seat. When the locking elements 39 are engaged with the mounting 42 on the floor of the vehicle the wheel 36 rests on the floor but is not load bearing. When the locking mechanism is unlocked the seat and frame can be tipped back onto the wheel 36 which lifts the locking elements 39 clear of the mounting 42 and allows the seat to be wheeled out of the vehicle.

The locking mechanism 34 also comprises a folding handle 43 which has the same functionality as the handle 33 shown in figures 1-7 with the addition of a hinge 44 between the handle and the locking element 39. The hinge 44 allows the handle to be folded away when it is not in use so that the locking mechanism is not unintentionally unlocked.

Claims

1. A seat locking mechanism for a vehicle comprising a plurality of locking elements arranged to engage and lock with a mounting provided on the floor of the vehicle, wherein the locking elements are each arranged to rotate between locked and unlocked positions and are engaged with one another so that rotation of one locking element causes simultaneous rotation of all locking elements, and wherein each locking element comprises a locking portion that is arranged to engage the mounting in the locked position thereby securing the seat to the vehicle.

2. The seat locking mechanism of claim 1 further comprising a body wherein the locking elements extend through the body and each locking element comprises a cam which engages the body and causes the locking element to move axially when rotated.

3. The seat locking mechanism according to claim 2 wherein the locking elements each comprise two opposing cam surfaces which locate the locking elements relative to the body.

4. The seat locking mechanism of any preceding claim further comprising a biasing means which biases the locking elements into the locked position.

5. The seat locking mechanism according to claim 4 wherein the biasing means is a resilient strip which is deformed by rotation of the locking elements when moved into the unlocked position.

6. The seat locking mechanism of any preceding claim wherein the locking elements are arranged linearly.

7. The seat locking mechanism of any preceding claim wherein one of the locking elements comprises a handle arranged to rotate the locking element.

8. The seat locking mechanism of any preceding claim wherein the locking elements are engaged with one another via teeth.

9. The seat locking mechanism of any preceding claim wherein when moving from the unlocked to the locked position the locking elements rotate and lift simultaneously.

10. The seat locking mechanism of any preceding claim further comprising a mounting arranged to be secured to the floor of a vehicle, wherein the mounting comprises two sides and a base which define a slot along the length of the mounting and wherein both sides are bent towards one another to form a lip.

11. The seat locking mechanism according to claim 10 wherein the locking portion is a disk with protruding lugs which are arranged to enter the slot in the mounting in the unlocked position and to engage behind the lip when rotated into the locked position.

12. The seat locking mechanism of claim 11 wherein the mounting defines indentation formed at regular interval along the length of the slot and the disk comprises a profile shaped to engage indentations in the locked position.

13. The seat locking mechanism of any preceding claim wherein the mechanism is arranged to attach to a frame of the seat.

14. The seat locking mechanism of claim 13 further comprising a wheel arranged to engage the floor of the vehicle when the frame is in a tipped back position.

15. A seating locking mechanism substantially as described herein with reference to the accompanying drawings.