Abstract:
A simplified, low-cost actuator used in conjunction with a lumbar support device designed to significantly decrease manufacturing costs and assembly time. The present invention produces similar movement as the more expensive actuators but does so with a considerably smaller number of parts. The actuator consists merely of four pieces—a handle, a spring, a plunger, and a mounting bracket. The symmetry of design of this actuator allows it to be installed more easily in any orientation and on either side of the seat. Furthermore, the actuator may be adapted for use with a tension cable or a drive rod. The simplicity, low-cost, and ease of use associated with this actuator makes it an attractive alternative to other actuators disclosed in the prior art. Finally, this actuator allows adjustable lumbar support to be offered in a cost effective manner in lower tier seating.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     None.  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not Applicable.  
       APPENDIX  
       [0003]     Not Applicable.  
       BACKGROUND OF THE INVENTION  
       [0004]     1. Field of the Invention  
         [0005]     This invention relates generally to actuators and, more particularly, to actuators used in connection with lumbar support systems. The invention is generally targeted for use in seats manufactured for the airline and furniture industries but can be used in all types of seating. The lever actuator disclosed herein is designed to provide a simple inexpensive alternative to the actuators normally used in lumbar support systems.  
         [0006]     2. Related Art  
         [0007]     It is well known in the art to use an actuator to provide movement in a lumbar support device located within a seat frame. Normally, the lumbar support devices are offered in the higher end, more expensive costing seats. For example, seats manufactured for use in automobiles often contain lumbar support systems. However, lower tier seating such as those used in airplanes often do not possess the lumbar support feature because the seats cannot be manufactured in an economical manner. The extra cost associated with adding lumbar support to a seat is in part due to the manufacturing and assembly costs of the actuator used to move the lumbar device. Types of actuators range from complex electric motors to simple turn wheels. Normally, the actuators used in these types of systems are composed of as many as 25 different parts. Such a configuration causes significant labor costs in assembling the actuator as well as extra costs relating to the manufacture of each component. As such, more economically priced seats often fail to offer the lumbar support devices that expensive seats may contain. There is a need in the art for a simple seat actuator that is inexpensive to manufacture and is simple to assemble so that lumbar support may be offered in more economically priced seats.  
         [0008]     Also known in the art is a type of actuator that works in a ratcheting type fashion. These actuators employ the use of technology often seen in car braking systems. An example is the actuator disclosed in reference FR2765531. However, these types of actuators are normally complex, employing the use of many different parts. The use of many parts makes the actuator more susceptible to breakdown, especially when used in situations such as an airplane where the seat is subject to significant forces on takeoff and landing. Furthermore, with the ratcheting actuators, the seat occupant lacks the desired feel for the amount of support that will be provided with each pull of the handle. There is a need in the art for a less complex actuator that provides the feel that seat occupants desire.  
       SUMMARY OF THE INVENTION  
       [0009]     It is in view of the above problems that the present invention was developed. The invention is an actuator consisting of only four different pieces. As such, the costs of manufacturing and assembling the lever actuator are significantly less than other options offered in the prior art. The low cost of this actuator allows the lumbar support option to be offered in less expensive types of seating.  
         [0010]     There are also advantages of this invention that relate to the actual operation of the lumbar support device. Normally, the actuator is connected to the lumbar support device through the use of a tension cable. The tension cable that is often used in this type of arrangement is a Bowden cable. A Bowden cable consists of a wire with wire ends on each side. The wire slides axially through a wire covering, sometimes referred to as a sleeve or conduit. In order to provide tension, the wire end is normally attached to a moving part while the sleeve is attached to a stationary unit. The moving part extends the wire away from the sleeve, thus creating a corresponding movement of the other wire end relative to the other sleeve end. The movement is used to actuate the lumbar support device. Instead of using a Bowden cable, some actuators are designed to operate in connection with a drive rod. In such instances, the actuator is connected directly to the drive rod such that movement of the actuator is transferred to the drive rod which in turn causes movement within the lumbar system. Often, a piece of the actuator is rotated thus causing the drive rod to rotate in a similar type fashion.  
         [0011]     An advantage of this invention is that it can be adapted for use with either a Bowden cable or a drive rod. Such flexibility allows this actuator to be used in a variety of types of lumbar support systems. Furthermore, because of the symmetry of this invention, it can be used on both the right and left sides of the seat. This not only eliminates the need to purchase side specific actuators, it also allows for decreased assembly time and greater flexibility in the mounting placement and configuration within the seat.  
         [0012]     A further advantage that this invention possesses over ratcheting type actuators is that it provides superior feel to the seat occupant. As seen in many ratcheting actuators, the user must pull the handle several times to achieve the maximum amount of support offered by the lumbar system. Each time the handle is pulled, however, the user does not know how close it is to maximum support. As such, the user is not aware of the amount of support that will be provided with each pull of the handle. In this invention, however, the handle stays in the position in which it is locked. As such, it gives the seat occupant greater feel for the amount of support that will be received with the movement of the handle and clearly indicates to the user the maximum level of support that will be provided by the lumbar system. In addition, the present invention is simpler than ratcheting type actuators. By employing a fewer number of parts, the chances of breakdown are dramatically decreased.  
         [0013]     The invention comprises of only four pieces—a handle, a spring, a mounting bracket, and a plunger. The handle contains a shaft. The plunger is seated within the shaft and runs the length of that shaft. The plunger contains a set of teeth at one end for engaging a gear set located within a mounting bracket. A spring is attached to the plunger such that the spring pushes the set of teeth into the gears. When this occurs, the handle is locked and cannot be rotated to other positions. At the other end of the plunger is a push button. When pressure is applied to the push button, the plunger slides through the shaft and compresses the spring causing the teeth to disengage from the gear set. With the push button pressed, the handle is free to rotate in a clockwise or counterclockwise manner. Once the push button is released, the spring forces the teeth back into the gear set thus locking the handle and preventing its further movement.  
         [0014]     The handle is engaged with the mounting bracket such that it will rotate around the bracket in a circular manner. The handle may be rotated in either direction to achieve varying degrees and positions of support. In this invention, rotation of the handle, in either direction, causes movement within the lumbar support device. Such movement is transferred to different parts of the system such that a greater or lesser amount of support is provided to the seat occupant relative to the direction the handle is moved.  
         [0015]     As stated earlier, in this invention the handle can be attached to either a Bowden cable or a drive rod. In either type of connection, when the handle is rotated, the movement is transferred to the cable or the shaft thus moving other support components within the lumbar system. In one embodiment of this invention, the handle is connected directly to a drive rod. The drive rod runs horizontally across the seat back and is connected to the seat frame such that the rod can still rotate as the handle is moved. The rod has springs attached to it in such a manner that when the handle is moved in one direction, the springs push on the lower portion of the seat providing additional lower back support, and when the handle is moved in the opposite direction, the springs push on the upper portion of the seat providing additional upper back support. When the handle is moved to a middle position, the springs provide additional middle back support.  
         [0016]     Further features and advantages of the present invention, as well as the structure and operation of various embodiments of the present invention, are described in detail below with reference to the accompanying drawings.  
     
    
     BRIEF DESCRIPTION OF TIE DRAWINGS  
       [0017]     The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and together with the description, serve to explain the principles of the invention. In the drawings:  
         [0018]      FIG. 1B  is a perspective view of the handle;  
         [0019]      FIG. 1B  is a side view of the handle in connection with a lumbar support system;  
         [0020]      FIG. 2  are perspective views of the plunger;  
         [0021]      FIG. 3  is a perspective view of the mounting bracket; and  
         [0022]      FIG. 4  are perspective views of the actuator with the handle, spring, and plunger being assembled.  
         [0023]      FIG. 5  is an illustration of a lumbar system employing the use of a drive rod. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]     Referring to the accompanying drawings in which like reference numbers indicate like elements,  FIGS. 1-4  are perspective views of different components of the present invention.  FIG. 1A  shows the different aspects of the handle  10 . The handle  10  possesses a shaft  30  running from the top of the handle to the circular base. This shaft  30  generally runs down the portion of the handle  10  facing the seat. In this embodiment, the shaft  30  is defined by only three walls on the interior of the handle  10 . However, in other embodiments, the shaft  30  may be completely enclosed within the interior of the handle  10 . Two pegs  32  are located on two of the three sides of the interior of the shaft  30 . These pegs  32  are used to connect the plunger  12  to the handle  10 . In the center of the circular base of the handle  10  is an attachment piece  26 . The attachment piece  26  provides the connection point for the drive rod  48  or the tension cable  42 .  FIG. 1B  is an illustration of the handle  10  in connection with a tension cable  42  such as a Bowden cable. The tension cable  42  may be attached in any way that is known in the art for attachment of a tension cable to an actuator. It is also recognized that the tension cable  42  may be replaced by a drive rod  48 .  FIG. 1B  also illustrates that lumbar support system. The system general contains a support surface  44  and a guide  46 . The guide  46  mediates travel of the support surface  44  from a non-supporting position to a supporting position, or vice versa. Movement is provided through the use of a tension cable  42  being operatively engaged to the support surface  44  and the guide  46 .  
         [0025]      FIG. 2  shows perspective views of the plunger  12 . The plunger is slightly longer than the shaft  30  in length. One end of the plunger  12  contains a platform  34  possessing a set of teeth  24 . When assembled, the platform  34  and teeth  24  extend into the circular base of the handle  10 . The underside of the platform  34  possesses a spring attachment area  28 . The attachment area  28  may take a variety of forms but this embodiment merely possesses a recessed area of corresponding size with the diameter of the spring  14 .  
         [0026]     The teeth  24  located on the platform  34  are designed to engage a gear set  18 . This engagement keeps the handle  10  in a fixed position and prevents it from rotating. On the opposite end of the plunger  12  is a push button  36 . When assembled, this push button  36  extends through the top of the shaft  12  and extrudes out from the top of the handle  10 . The push button  36  provides the surface area in which force may be applied to move the plunger  12  within the shaft  30 . Somewhere between the push button  36  and the platform  34  is a groove  22 . This embodiment features two grooves  22 , each running parallel with the shaft  30  along two sides of the plunger  12 . Access to the grooves  22  may be obtained through two slots  20  located at various lengths along the groove  22 . In this embodiment, the slots  20  are located at the top of the groove  22  relative to the push button  36  and somewhere near the midpoint of the groove  22 . The position of these slots  20  are ideally placed when the pegs  32  located within the shaft  30  may gain easy access to the groove  22  but that future exit from the groove  22  will not easily be obtained once the spring  14  is engaged with the platform  34 . The groove  22  is designed in such a manner than when the pegs  32  are inserted into the groove  22 , the plunger  12  is only able to slide through the shaft  30  a distance equal to the length of the groove  22 . Furthermore, the groove  22 , in combination with the pegs  32 , prevents the plunger  12  from completely exiting the shaft  30  once the force exerted by the spring  14  is applied.  
         [0027]      FIG. 3  is a perspective view of the mounting bracket  16 . The mounting bracket  16  possesses a gear set  18  in its interior portion through which the teeth  24  of the plunger  12  may attach. While in this embodiment the gear set  18  only extends partially along the interior of the mounting bracket  16 , other embodiments may contain gear sets  18  extending throughout the entire interior of the mounting bracket  16 . The mounting bracket  16  is generally shaped in a circular fashion to correspond with the circular base of the handle  10 . However, the mounting bracket  16  may take any shape such that it contains a gear set  18  for engagement of the teeth  24 . The mounting bracket  16  also has two flanges  40  with holes for anchoring screws so that the unit may be mounted on a seat frame. Finally, the mounting bracket  16  contains an opening such that the attachment piece  26  of the handle  10  may extend through the opening and connect with either the Bowden cable or the drive rod  48  of the lumbar support system.  
         [0028]      FIG. 4  are drawings of the plunger  12 , handle  10 , and spring  14  being assembled. During the assembly process, the plunger  12  is placed within the shaft  30  of the handle  10 . The plunger  12  is connected to the handle  10  through the use of pegs  32 . The pegs  32  are inserted into the groove  22  via the slots  20 . Once the pegs  32  are inserted into the slots  20 , they enter the groove  22  and may travel the length of the groove  22  without easily exiting the slots  20 . Once the pegs  32  are inserted into the groove  22 , the spring  14  is compressed and attached to the spring attachment area  28  located on the underside of the platform  34 . This connection may be made in a variety of ways but in this embodiment, the spring  14  is merely placed between the attachment piece  26  and the spring attachment area  28 . In this embodiment, the spring  14  generally acts as a resilient compression piece, and it will be appreciated that any type of spring or its equivalent, including any type of compressions piece, can be used in the present invention. When released, the spring  14  pushes the plunger  12  to a position such that the bottom set of pegs  32  engage the lower end of the groove  22  relative to the push button  36 .  
         [0029]     In order to complete assembly, the handle  10  is placed onto the mounting bracket  16 . Pressure is applied to the push button  36  forcing the plunger  12  to slide down the shaft  30  and compress the spring  14 . The handle  10  is then placed on the mounting bracket  16  such that when the push button  36  is released, the spring  14  will push the plunger  12  up the shaft  30  and the teeth  24  will become engaged with a portion of the gear set  18 .  
         [0030]     Operation of this actuator is also very simple. When the seat occupant desires a change in the amount of lumber support being provided, the occupant merely needs to press down upon the push button  36 . Such force moves the plunger down the shaft  30  compressing the spring  14 . At this point, the teeth  24  have been disengaged from the gear set  18 . The occupant then may rotate the handle  10  in a clockwise or counterclockwise direction to adjust the level of support being provided. Once the desired support is being received, the occupant merely releases the push button  36  and the spring  14  forces the plunger  12  up the shaft  30  and the teeth  24  become engaged with a different portion of the gear set  18 . When the teeth  24  become engaged with the gear set  18 , the handle  10  is prevented from moving and thus the support being received will be maintained.  
         [0031]      FIG. 5  shows a lumbar system using a drive rod  48  instead of a tension cable. The drive rod  48  is connected to the actuator  52  and the seat frame. The rod  48  has springs  50  attached to it in such a manner that when the handle is moved in one direction, the springs push on the lower portion of the seat providing additional lower back support, and when the handle is moved in the opposite direction, the springs  50  push on the upper portion of the seat providing additional upper back support.  
         [0032]     In view of the foregoing, it will be seen that the several advantages of the invention are achieved and attained.  
         [0033]     The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.  
         [0034]     As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. For example, even though this actuator is primarily intended to be used in conjunction with lumbar support devices for seats used in the airline and furniture industries, it can be used to provide actuation in any type system employing the use of a tension cable or a drive rod. Similarly, as discussed above, any type of spring or other compression device can be used in the present invention, such as a shock. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.