WO1997003861A1

WO1997003861A1 - Seat positioning track with memory feature

Info

Publication number: WO1997003861A1
Application number: PCT/IB1995/000707
Authority: WO
Inventors: Alan George Dry; Andrew Allan Walz; Gregory James Alexander Andrigo; Randy W. Corey; Ulrich Heinz Edmund Stegelmeier
Original assignee: Rockwell International Corporation
Priority date: 1995-07-21
Filing date: 1995-07-21
Publication date: 1997-02-06

Abstract

An improved seat positioning device provides a memory feature. A memory block (38) is selectively positioned at any selected position by an operator. A locking block (44) is fixed for movement with the seat and is selectively secured (46) to the memory block to secure the seat at the desired position. The locking block may be released from the memory block to allow the seat to move forwardly. In this movement, the memory block remains stationary. The locking block also has structure for moving the memory block (38), such that the desired position may be changed. The memory block is preferably provided with a plurality of plungers (70, 72, 74) spaced by a first distance. One of the plungers is selectively received within a plurality of apertures (32) associated with a lower channel (26) of the positioning mechanism. The apertures in the lower channel are spaced by a second distance that is not equal to the first distance. The unequal distances provide finer gradation in the number of available positions for the seat relative to the vehicle. In addition, the memory block and at least portions of the locking block are preferably fully received within the upper and lower U-shaped channels (24, 26). The upper and lower channels protect the locking mechanism from dirt or debris. Also, the apertures in the lower channel are preferably mounted in a strip (30) positioned slightly vertically above the bottom wall of the lower channel. Thus, there is space below the apertures such that the plungers are able to fully extend to hold the seat firmly at the desired position.

Description

SEAT POSITIONING TRACK WITH MEMORY FEATURE

BACKGROUND OF THE INVENTION

This invention relates to a seat positioning track that has a mechanical memory feature to return the seat to a desired position.

In the prior art, seats slide forwardly and rearwardly relative to the vehicle on positioning tracks. These tracks are typically placed at each lateral side of the seat, and comprise upper and lower U-shaped channels. The upper channels are mounted to the seat and the lower channels are mounted to the

vehicle floor. The seat is allowed to slide forwardly and rearwardly relative to the vehicle on the channels.

In the past, selectively releasable locking mechanisms lock the seat at any one of several positions spaced incrementally forwardly and rearwardly of the vehicle. Typically, openings are formed on each of the upper and lower channels, and pins extend through selected openings to lock the seat at a desired position. This positioning system has some deficiencies in that one would like to define a pre-set "memory" position for the seat to a desired position for a particular operator. The above mechanical positioning tracks are often used on a front seat in a two-door vehicle. Passengers in the rear seats often release the front seat to move forwardly to the forward-most extent of the range of travel such that the passengers in the rear seat may exit the vehicle. It would be desirable to have the positioning mechanisms for those seats facilitate return of the seats to the pre-set memory position.

While the prior art has proposed mechanisms with a memory feature, they have been deficient in some regards. In particular, the prior art memory mechanism may not have provided adequate strength holding the seat at a desired position. Moreover, the prior art mechanisms have not provided sufficient adjustability of the memory position. That is, the prior art memory

mechanisms have only a limited number of positions for the seat. Finally, the prior art mechanisms have left operational components exposed to debris and dirt.

SUMMARY OF THE INVENTION

In a disclosed embodiment of this invention, a seat is mounted to a vehicle on a pair of channels. An upper channel is fixed to the seat while a lower channel is fixed to the vehicle floor. A positioning mechanism is received within the two channels, protecting the positioning mechanism from dirt and debris. The positioning mechanism preferably includes a memory block that fixes a pre-set memory position for the seat. A locking block moves with the seat, and is selectively secured to the memory block. When a passenger releases the seat to move forwardly, the memory block stays with the lower channel. The locking block moves with the seat forwardly. When the passenger has exited, the seat returns to the memory position. The locking block secures the seat at the memory position by being secured in the memory block. The memory block securely holds the seat relative to the vehicle and the lower channel. A strong secure connection is provided.

The memory block is preferably provided with at least three plungers, one of which is received within one of a number of incrementally spaced openings in a track associated with the vehicle floor. The three plungers are spaced from each other by a distance that is different than the distance between the openings in the track. The distinct differences in spacing between the plungers and the holes in the track provides finer gradations in available positioning for the seat. An operator will be able to select a desired memory position with a finer degree of control than in the prior art, where less fine gradations are provided.

In other features of this invention, the locking block includes a plunger that is biased downwardly, and is selectively received in a locking aperture in the

memory block. A cable received adjacent the rear of the seat is selectively actuated by a rear seat passenger to release the locking block, and allow the seat to be moved forwardly such that the passenger may leave the rear of the vehicle.

A lift arm is associated with the locking block, and has a pair of tabs which are associated with channels on the memory block. The lift arm is

selectively actuated by a second cable positioned near the front of the seat. The second cable lifts the lift arm, which in turn lifts the memory block. The memory block may thus be moved to change the set memory position.

In a most preferred embodiment of this invention, both the lift and the locking plungers are actuated by pivoting members which pivot on a common axis. These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a partial view of a vehicle seat.

Figure 2 shows the functional components of the positioning assembly of

the present invention. Figure 3 is a side view of the components shown in Figure 2.

Figure 4 is a cross-sectional view through the components shown in Figure 3.

Figure 5 is a side view of the components shown in Figure 3 in a locked position.

Figure 6 is a cross-sectional view along line 6-6 as shown in Figure 5.

Figure 7 shows a cross-sectional view of the components in the Figure 5 position.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Figure 1 shows a vehicle seat 20 mounted to the floor 22 of a vehicle. An upper U-shaped channel or track 24 is fixed to the seat 20, and a lower channel 26 is fixed to the floor of the vehicle 22. The two U-shaped channels

24 and 26 are generally as known in the art and form no portion of this invention. The two channels guide seat 24 movement forwardly and rearwardly of the vehicle, or into and out of the plane of Figure 1. A positioning mechanism 28 is received with a space defined by channels 24 and 26 such that it is protected. In the prior art, the positioning mechanisms have sometimes been positioned outwardly of the channel, and thus have been exposed to dirt or debris. Figure 2 shows the positioning mechanisms 28. A metal strip 30 has a plurality of incrementally spaced openings 32. Strip 30 is bolted at spaced locations 34 through spacers 36 to the bottom of lower channel 36. Thus, track 30 is positioned slightly vertically above a bottom wall 37 of the lower channel 26. As will be explained, since the apertures 32 are spaced slightly above the bottom wall 37, any dirt or debris which may enter the U-shaped channels will not impede movement of plungers through the apertures 32 to lock the seat at a desired position.

A memory block 38 is received on the strip 30, and includes a release channel 40, and guide ledges 42, which guide sliding movement along strip 30. Channel 40 is part of a plate 43 that moves relative to memory block 38, as explained. A locking block 44 includes a plunger 46 which is selectively received within an aperture 47 to lock the locking block 44 to the memory block 38. A

release lever 48 releases the plunger 46 from the aperture 47. Lever 48 pivots on a pivot point 50, and is actuated by a knob 52 which pulls a cable 54 which is received within a cable slot 56 on lever 48. A guide plate 58 also guides cable 54. Knob 52 is positioned adjacent to rear side of seat 20. A compressed spring 59 rides on cable 54 and biases leer 48 against plunger 46.

A second lever 60 also pivots on axis 50, and has its own actuation knob 62 actuating cable 64, which passes through a guide plate 66, and is received in a cable slot 67 in lever 60. Lever 60 is connected to a lift arm 68 through a pin 69. Lift arm 68 includes ridges 70 which are selectively received within channel 40 to allow release of the memory block 38, as will be explained below. A compressed spring 71 biases lever 60 and lift arm 68 downwardly. In the position shown in Figure 3, the lock block 44 is not locked to the memory block 38. Memory block 38 is positioned at a desired position for a particular operator of the vehicle. The memory block will remain in that position. When the lock block 44 is in the position shown in Figure 3, the seat itself may move away from and relative to the memory block 38. A passenger in the rear seat might move the seat to this position when leaving a vehicle such as a two-door vehicle. The passenger in the rear seat would actuate the cable knob 52 against the force of spring 59, and release the lock block 44 from the memory block 38, as will be explained in more detail below. As shown, in this lift arm 68 is not aligned with the channel 40.

As shown in Figure 4, the memory block 38 has at least three plungers 70, 72 and 74 which are all biased downwardly by springs 76. One of the plungers 74 extends through one of the apertures 32 in strap 30. The plungers all have a ramped forward face 77 facilitating alignment and movement into one of the apertures 32. The plungers are spaced by a distance dl, which is different than the distance d2 between the apertures 32. In this way, when an optimum position for the seat is determined, there will be a minimal amount of distance that the operator must move from the optimum position to find a position wherein one of the plungers 70, 72 and 74 does align with one of the incrementally spaced apertures 32. In this way, finer adjustment of the position for the memory block 38 and hence the seat, is achieved.

As also shown a central portion 42c of guides 42 extends below the strap 30. Central portion 42c has apertures 42a aligned with plungers 70, 72, 74. The plunger that extends through an aperture 32, also extends through an aperture 42a to provide a secure connection.

As shown, the locking plunger 46 has a rear ramped face 80 that facilitates movement of the locking plunger 46 upwardly on a forward ramp face 82 of the memory block 38. The plunger is spring biased downwardly by spring 59, and the ramped surface guides its movement upwardly onto memory block 38. This facilitates movement of the seat back to its locked position as is shown in Figure 5.

In the locked position shown in Figure 5, the locking block 44 now has its plunger 46 received within the aperture 47 in the memory block 38. The memory block 38 defines a memory position on the strap 30, and the locking block 44 is now securing the seat to the memory block 38, and hence to the vehicle floor through the strap 30 and the lower U-shaped channel. As shown central portion 42c connects the guides 42. The memory block 38 and the locking plunger are received in a space defined between the lateral walls of channels 24 and 26.

As shown in Figure 6, when in this locking position, the ridges 70 of the lift arm 68 are received within the channel 40. The channel has in-turned ears

83. One of the plungers 74 is shown extending through an aperture 32 in the strap 30 in this position. When the operator wishes to release the memory block

38 from this position, the cable 64 is actuated.

Preferably, the cable knob 62 is positioned near the front of the seat, and the operator may actuate the cable know 62 to change the memory position. When the cable knob 62 is actuated, the lift arm 68 is lifted, and the ridges 70 abut ears 83 and lift channel 40, and hence plate 43, upwardly. As can be appreciated from Figures 4 and 7 if plate 43 is lifted it lifts the plunger 74 out of aperture 32. The plunger 74 is thus moved outwardly of the aperture 32. The operator may now readjust the memory position for the seat forwardly or rearwardly. Once the operator determines a new desired position, the cable knob 62 is released, and one of plungers 70, 72 and 74 will again be received within an aperture 32 to define a new predetermined or memory position.

As shown in particular in Figure 6, the channels 24 and 26 enclose and protect the function components of the positioning mechanism 28. As shown in Figure 7, in this locking position such as shown in Figures 5 and 6, the plunger 46 is received within the aperture 47. The plunger 74 is received within an aperture 32. The plunger 74 is positioned above a bottom wall 37 of the lower channel 26 by spacers 36. Thus, there is no impediment to movement of the plunger 74 through the aperture 32 as might be the case if aperture 32 was adjacent the bottom wall 37. Further, there is a secure connection from plunger 74 in aperture 32 ensuring a secure connection of the seat to the vehicle floor. The same is true with the plunger connection 46 to the aperture 47. The plunger are sized such that they are a close fit within their respective apertures. Thus, a secure connection is provided. In preferred embodiments of this invention, the memory block 38 is preferably of a powdered metal. The guide 42 is preferably formed of self lubricating material.

A preferred embodiment of this invention has been disclosed. However, a worker of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.

Claims

1. A seat positioning assembly comprising: an upper channel for being mounted to a seat; a lower channel for being mounted to a vehicle; and a positioning mechanism including a memory block for defining a pre-set memory position, and a locking block for selectively securing a seat at the pre-set memory position, said locking block being fixed to move with said upper channel, and said memory block being selectively secured to said lower channel such that said locking block may move independently of said memory block, and said memory block being received between lateral sides of said channels such that said channels enclose at least said memory block.

2. An assembly as recited in Claim 1, wherein a strip defining a plurality of incrementally spaced apertures, said memory block includes at least one memory plunger extending downwardly through one of said apertures in said strip.

3. An assembly as recited in Claim 2, wherein said strip is mounted slightly vertically above a bottom wall of said lower channel such that there is a free space beneath said aperture.

4. An assembly as recited in Claim 2, wherein there are a plurality of said memory plungers.

5. An assembly as recited in Claim 4, wherein said plurality of memory plungers are spaced by a first distance, and said apertures in said strip being spaced by a second distance, said first distance being unequal to said second distance such that there is a finer range of spacing available for the seat.

6. An assembly as recited in Claim 2, wherein said locking block has lift structure for selectively engaging mating structure on said memory block, said lift structure on said locking block being selectively actuatable to lift portions of said memory block and allow said memory block to move with said locking block.

7. An assembly as recited in Claim 6, wherein said lift structure includes a lift arm which is selectively actuatable to lift said plunger and allow said memory block to move with said locking block.

8. An assembly as recited in Claim 7, wherein said lift arm includes a member at each lateral side of said locking block, said members selectively engaging mating structure on said memory block, allowing said lift arm to lift said mating structure and allow said memory block to move with said locking block.

9. An assembly as recited in Claim 8, wherein said locking block includes a lock plunger that is selectively received within an aperture in said memory block, a first cable selectively actuating said lock plunger to allow said

plunger to move outwardly of said aperture and allow said locking block to move relative to said memory block, and a second cable actuating said lift arm to allow said memory block to move with said locking block.

10. An assembly as recited in Claim 9, wherein said lock plunger and said lift arm are both actuated by pivoting members.

11. An assembly as recited in Claim 10, wherein said two pivoting members pivot on a common axis.

12. An assembly as recited in Claim 9, wherein said lock plunger is biased downwardly, said lock plunger having a ramped face, said memory block having a mating ramped face for facilitating movement of said lock plunger onto said memory block.

13. An assembly as recited in claim 12, wherein said spring bias is provided by a spring received on said table.

14. An assembly as recited in claim 8, wherein said mating structure includes a plate that moves vertically relative to said memory block to lift said plunger.

15. A method of positioning a seat comprising the steps of: a) providing upper and lower channels and a seat positioning mechanism comprising a locking block and a memory block, said locking block being selectively movable relative to said memory block; b) positioning said seat at a desired position, and engaging said seat at said desired position by securing said memory block to the vehicle, and securing said locking block to said memory block, said locking block being secured to said seat;

c) releasing said seat to move forwardly by releasing said

locking block from said memory block; d) adjusting the position of said memory block by engaging said locking block and said memory block, and releasing said memory block from said lower channel; and e) determining a new desired position for said seat, resecuring said seat at said new desired position by securing said memory block to said lower channel at said new desired position, and securing said locking block to said memory block at said new desired position.

16. A method as recited in Claim 15, wherein said memory block includes a plurality of plungers that are selectively secured in at least one aperture associated with said lower channel, said memory block remaining at a desired position until released in step d) and said locking block being selectively secured to said memory block by at least one plunger secured in an aperture in said memory block, until being released in step c).

17. A seat positioning assembly for positioning a seat at a desired position comprising: a seat; an upper and lower channel, said upper channel being fixed to said seat, and said lower channel being adapted to be fixed to a vehicle, said upper and lower channel guiding said seat for sliding movement forwardly and rearwardly in a vehicle; a positioning mechanism comprising a memory block and a locking block, said memory block selectively defining a desired position, and said locking block securing said seat at said desired position, said locking block being selectively movable relative to said memory block to allow the seat to be moved without changing said desired position, said lower channel comprising a plurality of incrementally spaced securement members, and said memory block comprising a plurality of incrementally spaced securement members, at least one of said memory block securement members engaging one of said securement members on said lower channel to secure said memory block at said desired position, the incremental spacing between said securement members on said memory block being different than the incremental spacing of said securement members on said lower channel such that finer gradation of available positions for said memory block are made available.

18. An apparatus as recited in Claim 17, wherein said securement members on said memory block are a plurality of plungers which are spring biased downwardly, and said securement members on said channel are a plurality of incrementally spaced apertures.

19. An apparatus as recited in Claim 18, wherein said apertures in said channel are formed in a strip which is mounted slightly vertically above a bottom wall of said lower channel.

20. An apparatus as recited in Claim 19, wherein spacers mount said strip above said lowermost wall of said lower channel.

21. An apparatus as recited in Claim 17, wherein said locking block is selectively secured to said memory block by a spring biased lock plunger.

22. An apparatus as recited in Claim 21, wherein said lock plunger and said memory block having mating ramped surfaces to facilitate movement of said lock plunger onto said memory block.