Chair tablet arm apparatus

Information

  • Patent Grant
  • 6375257
  • Patent Number
    6,375,257
  • Date Filed
    Monday, June 12, 2000
    24 years ago
  • Date Issued
    Tuesday, April 23, 2002
    22 years ago
Abstract
A tablet arm apparatus providing a re-positionable and stowable tablet work surface which is easily mounted on a chair or integrated into a chair design is described in which movement in each axis is independent and is accomplished by an articulating arm assembly or a single inexpensive two-axis hub.
Description




BACKGROUND OF THE INVENTION




The present invention relates to a tablet arm for furniture, particularly a chair. More specifically, the invention concerns a work tablet that mounts to a chair and uses an assembly having two or more degrees of freedom to pivot and rotate the tablet from a vertical stowed position at the side of the chair to an deployed position above and parallel to the seat of the chair.




A number of chair tablet designs have a mechanism that support the work tablet in a first horizontal position over the chair seat and in a second stowed position when the tablet is not in use. However, few designs have provided an apparatus that can be integrated into the chair design and that allow repositioning of the tablet from above the chair seat to a position to the side of the chair by both rotating the tablet from the horizontal plane to the vertical plane or, when the tablet is in use, by merely swinging the tablet in the horizontal plane. Further, as an easily mountable accessory to a chair, none of the existing tablet designs provide rotation of the tablet from the horizontal plane to the vertical plane and independent rotation in the vertical plane to a stowed position along the side of the chair using a single inexpensive two-axis hub.




One design that provides a horizontal tablet position above a chair and repositions to a stowed vertical position at the side of the chair is Bauman et al., U.S. Pat. No. 5,683,136. The tablet must be pivoted from the horizontal to the vertical plane using one pivot joint then slid to a position along the side of the chair using a slide mechanism. This design does not allow repositioning of the tablet without rotating it from the horizontal plane, nor does it allow the tablet to be rotated within the horizontal plane.




Two designs that use angled pivot joints for positioning are Benoit, U.S. Pat. No. 4,216,994, and Phoon, U.S. Pat. No. 5,845,964. The angled pivot joints cause the tablet to be rotated through the horizontal and vertical planes simultaneously. Other designs, such as the patent to Sorenson, U.S. Pat. No. 5,765,911, allow motion in one plane independent of the other and movement of the tablet without upsetting its horizontal position. However, such designs require manual loosening and re-tightening of friction brakes before and after repositioning.




The alternative design of Kanigowski, U.S. Pat. No. 4,852,940, provides multiple axis motion using a single ball-joint, but fails to provide integral stops or locks. In order to maintain a horizontal position, the chair arms or a shelf extending from them must support the tablet. A design patent to Best, U.S. Pat. No. 409,860,illustrates a mountable accessory, requiring two mounting bars and two single-axis pivot joints to provide repositioning to a stowed position.




In light of the shortcomings of these prior devices, there remains a need for a tablet arm apparatus that allows the tablet to rotate to a vertical position or to move through the horizontal plane without upsetting the other plane of motion and without having to fully stow the tablet for a person to enter or exit of the seat of the chair while requiring only one mount and one inexpensive two-axis joint and furthermore, not requiring manual friction brakes to lock an axis of motion of the tablet.




SUMMARY OF THE INVENTION




Briefly describing one aspect of the invention, the work tablet arm apparatus includes a tablet plate for mounting a work tablet and an articulating arm assembly providing various tablet positions and configured for attachment of the apparatus to a chair.




The difficulties with prior chair tablet arm apparatuses are overcome in one aspect of the current invention by the articulating arm assembly. The arm assembly in one embodiment includes a pivot rod assembly connecting one end of a long arm to one end of a short arm. The other end of the long arm can be rotationally connected to the tablet plate using a slotted washer and stop pin combination that allows limited rotation of the tablet independent of the arm position. The other end of the short arm can be pivotably mounted to the chair arm, preferably as an integral element of the chair design. In one aspect of this embodiment, the short arm pivot provides a means for moving the tablet from a position over the seat of the chair to the front of or other side of the arm of the chair. This pivot allows a person to enter or exit the seat without having to fully stow the tablet and without upsetting the contents of the tablet.




In a further aspect, the pivot rod assembly provides a means for rotating the tablet and long arm about an axis parallel with the chair seat. The pivot rod assembly can include a bias spring for engaging a locking pin into a locking notch, stopping rotation of the long arm when the tablet is parallel to the chair seat. The long arm rotation about the pivot rod provides for quick movement of the tablet when it is not in use. When combined with a pivot to the outside of the arm of the chair, the long arm also provides for stowing the tablet in a vertical position along the outside of the arm of the chair. The chair tablet arm apparatus requires no manual friction brakes and no external support of the tablet other than a single mounting point.




In another embodiment of the invention a chair tablet arm apparatus is provided as an accessory to an existing chair design and is capable of two-axis motion using a single inexpensive hub and a single mounting bracket. The chair tablet arm apparatus in this embodiment can include a tablet plate, a pivot hub assembly, a mounting bar, and a mounting bracket. The mounting bracket can function to attach the apparatus to an existing member of the chair such as a chair leg. The mounting bar rotationally attaches the mounting sleeve to the pivot hub assembly. The pivot hub can be pivotably attached to the tablet plate.




The pivot hub assembly can include spring-biased pins that engage the mounting bar, and are operable to stop rotation of the hub around the mounting bar when the tablet is at a rotational position for pivoting. The tablet plate can then pivot between a position perpendicular to a position parallel to the chair seat. In the perpendicular position, the tablet can rotate independently within the perpendicular plane to a stowed position at the outside of the chair member to which the apparatus is attached.




One object of the invention is to provide a stowable tablet arm apparatus that can be readily integrated into an existing chair using a single mounting point. Another object is to such a tablet arm apparatus that can provide two-axis motion using a single inexpensive joint.




One benefit is that the tablet can be rotated to a vertical position or moved through the horizontal plane without upsetting the other plane of motion and without having to fully stow the tablet for a person to enter or exit the seat of the chair. Another benefit is that the apparatus requires no manual friction brakes to lock an axis of motion of the tablet.




These and other objects, advantages, and features are accomplished according to the devices, assemblies, and methods of the present invention.











DESCRIPTION OF THE FIGURES





FIG. 1

is a perspective view of a chair tablet arm apparatus according to one embodiment of the invention, utilizing a single pivot hub assembly and shown in a deployed position.





FIG. 2

is a front elevational view of the chair tablet arm apparatus depicted in FIG.


1


.





FIG. 3

is a top view of the chair tablet arm apparatus depicted in FIG.


1


.





FIG. 4

is a perspective view of the chair tablet arm apparatus of

FIG. 1

mounted on a chair and in a deployed position.





FIG. 5

is a perspective view of the chair tablet arm apparatus depicted in

FIG. 1

but shown in a stowed position.





FIG. 6

is a top perspective view of a chair tablet arm apparatus according to a further embodiment of the invention, utilizing an articulating arm assembly.





FIG. 7

is a front elevational view of the chair tablet arm apparatus shown in

FIG. 6

but integrated into a chair design and shown in a stowed position at the outside of the chair arm.





FIG. 8

is a top plan view of a chair tablet arm apparatus shown in

FIG. 6

, but integrated into a chair design and shown in a deployed position at the outside of the chair arm and in a deployed position above the chair seat.





FIG. 9

is a perspective view of a chair tablet arm apparatus shown in

FIG. 6

but integrated into a chair design and with the tablet in a deployed position.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. The invention includes any alterations and further modifications in the illustrated devices and described methods and further applications of the principles of the invention which would normally occur to one skilled in the art to which the invention relates.




The present invention relates to a tablet arm apparatus for furniture, particularly a chair. More specifically, the invention concerns a work tablet that mounts to a chair and uses an assembly having two or more degrees of freedom to pivot and rotate the tablet from a vertical stowed position at the side of the chair to a deployed position above and parallel to the seat of the chair.




In accordance with one embodiment of the present invention, a chair tablet arm apparatus


10


is shown in FIG.


1


and as attached to a chair in FIG.


4


. The apparatus


10


contemplates a tablet plate


11


pivotably attached to a pivot hub assembly


16


, which is itself rotationally attached to a mounting bar


20


. The apparatus


10


can be generally constructed of plastic or lightweight metal and can be attached to a member of a chair, such as a chair leg, with a mounting bracket


27


as depicted in FIG.


4


. The apparatus is movable from a deployed position


10


″ (

FIG. 4

) above and parallel to the seat of the chair, and a vertical stowed position


10


′ at the side of the chair as depicted in FIG.


5


. The stowed position


10


′ facilitates easy access to or exit from the seat of the chair. The deployed position


10


″ provides a work surface functional to a person seated in the chair.




Referring to

FIGS. 1 and 2

, the mounting bracket


27


in one specific embodiment preferably includes two opposing “C” clamp portions


28


and


29


. Each clamp portion


28


and


29


defines a curved portion


28




a


and


29




a


forming a half cylinder, and a flat flange


28




b


and


29




b


extending the length of one end of the cylinder. The flange


28




b


of clamp portion


28


is attached to a long arm


21


of the mounting bar


20


, preferably at three weld points


32


. The apparatus


10


can be mounted to a chair leg, as depicted in

FIG. 4

, by first positioning the clamp portion


28


with the half cylinder


28




a


in contact with one side of the chair leg. The second clamp portion


29


is then placed in juxtaposed mirror image fashion so that the two half cylinders


28




a


and


29




a


cooperate to enclose the chair leg. Three alignment dimples


31


defined between the two flanges


28




b


and


29




b


align the clamp portions and the portions are drawn together by a number of screws


33


. The screws


33


and dimples


31


cooperate to allow the clamp portions


28


and


29


to firmly grip the chair leg. The interior of the half cylinder portions


28




a


and


29




a


of each clamp


28


and


29


is preferably lined with foam tape


30


to provide a firm attachment to the chair member


34


.




The mounting bar


20


extends from a long arm


21


through a 90-degree bend


23


to a short arm


22


. The pivot hub assembly


16


can include a bearing hub


17


, a retaining nut


19


, a rest bracket


24


, and a washer


25


. The hub assembly


16


is rotationally mounted on the short arm


22


of the mounting bar


20


, with the end


22


passing through a central opening


18


(

FIG. 3

) of the hub


17


. The retaining nut


19


, which is preferably a cap nut, can be attached to the short arm


22


of the mounting bar to trap the hub


17


between the retaining nut


19


and the washer


25


and rest bracket


24


. The rest bracket


24


is preferably fixed to the short arm


22


, such as at weld points


26


. The washer


25


provides a sliding surface for the hub


17


relative to the rest bracket


24


. In the deployed position


10


″ depicted in

FIG. 2

, the tablet plate


11


is supported by the rest bracket


24


in a generally horizontal attitude.




Referring to

FIG. 1

, the tablet plate


11


has a flat surface having multiple mounting holes


12


defined therethrough by which a solid work surface may be attached. The plate further includes a pair of mounting ears


13


forming a U-shape extend from one end thereof. The mounting ears


13


are spaced apart to receive the pivot hub


17


within the U-shape.




Each mounting ear


13


defines a co-linear thru-hole


14


. The thru-holes are sized to receive a corresponding spring pin


15


therein, with each pin extending toward the interior of the U-shape. The spring pins


15


can extend through opposite walls


17




a


and


17




b


of the hub


17


, as depicted in

FIG. 3

, to mount the tablet plate


11


to the hub for rotation therewith. At a rotational position in which the tablet plate


11


is in a plane sharing one axis with the chair seat, the spring pins


15


can engage detents


35


defined on opposite sides of the short arm


22


of mounting bar


20


. The detents


35


cooperate with the ends of the pins


15


to resist rotation of the hub


17


and tablet plate when the pins reside within the detents. However, the spring pins are configured to allow the ends of the pins to slide out of the detents upon application of a moderate force rotating the hub


17


relative to the short arm


22


. The tablet plate


11


remains free to pivot about the axis of the spring pins


15


, and relative to the hub, permitting movement of the tablet plate between a horizontal and vertical position.




The hub


17


is preferably formed substantially entirely of nylon or a similar low-friction material. Most importantly, the hub opening


18


must have a low friction characteristic so that the hub, and therefor the tablet plate


11


, can freely rotate about the mounting bar. Likewise, the pin bores


16




a


and


16




b


must have a low friction characteristic so that the spring pins can pivot freely as the tablet plate is pivoted relative to the hub. In addition, the spring pins must be able to freely translate axially toward the detents


35


in the mounting bar.




The operation of the chair tablet arm assembly


50


is as follows. The stowed position


10


′ depicted in

FIG. 5

presents a well-situated location for the tablet when it is not in use. In the stowed position


10


′, the tablet plate


11


is oriented in a vertical position, perpendicular to the chair seat. The tablet plate mounting ears


13


are located at the top-most end of the tablet plate, which hangs from the pivot pins


15


. To re-position the tablet plate to the deployed position


10


″ depicted in

FIG. 4

, two steps are required. First, the tablet plate


11


is rotated within the vertical plane, rotating the hub


17


about the short arm


22


of the mounting bar


20


. At 180-degrees of rotation, the rotation position at which the mounting ears


13


are located at the bottom-most end of the tablet plate, the spring pins


15


engage the detent bores


35


on the mounting bar


20


, resisting further rotation. Second, the tablet plate


11


is pivoted about the pivot pins


15


from the vertical position toward the chair seat until the tablet plate contacts and is supported by the rest bracket


24


in the deployed position


10


″ depicted in FIG.


2


. Completion of the steps and movement of the tablet plate


11


in reverse order will return the tablet plate to the stowed position


10


′ depicted in FIG.


5


.




In a further embodiment of the invention, as depicted in

FIG. 6

, a tablet arm apparatus


50


contemplates a tablet plate


51


rotationally attached to an articulating arm assembly


81


. The assembly includes a slotted washer


53


, a long arm


61


, a pivot rod assembly


65


, and a short arm


77


. The apparatus


50


can be generally constructed of plastic or lightweight metal and can be attached to a member of a chair with the short arm


77


, preferably as an integral part of the chair design. The vertical stowed position


50


′ of the apparatus, at the side of the chair, is depicted in

FIG. 7. A

first deployed position


50


″ of the apparatus with tablet plate


51


parallel to the seat of the chair and to the outside of the arm of the chair is depicted in

FIG. 8. A

second deployed position


50


′″ above and parallel to the seat of the chair is further depicted in FIG.


8


. The first deployed position


50


″ and stowed position


50


′ facilitate access to or exit from the seat of the chair. The first and second deployed positions


50


″ and


50


′″ each provide a work surface functional to a person seated in the chair.




Referring to

FIG. 6

, the short arm


77


is pivotally mounted at one end


77




b


to the chair arm


58


. The other end


77




a


of the short arm


77


is attached to the pivot sleeve


69


of a pivot rod assembly


65


. One end


61




a


of the long arm


61


can be attached to a pivot rod


66


of the pivot rod assembly


65


. The pivot rod assembly


65


provides a means for the ends


61




a


and


77




b


of the arms


61


and


77


, respectively, which are not attached to pivot rod assembly, to articulate from a position extended and opposite each other, as depicted in

FIG. 6

, to a position toward each other, as depicted in FIG.


7


. The articulating translation allows tablet plate


51


to be rotated from the stowed position


50


′ depicted in

FIG. 7

to the first deployed position


50


″ along the outside of the chair arm


58


, depicted in FIG.


8


. The pivotable mounting of the short arm


77


, permits the entire tablet arm assembly


50


to pivot between the two deployed positions


50


″ to


50


′″, both depicted in FIG.


8


.




Referring to

FIG. 6

, the short arm


77


can be constructed of a section of rectangular tubing. The rectangular shape forms two wider sides


77




c


and


77




d


and two narrower sides


77




e


and


77




f.


Two thru-holes


78


are bored in the wider sides


77




c


and


77




d,


near one end


77




b,


to provide means for pivotably mounting the short arm


77


to a member


58


of the chair (FIG.


8


). At the same end


77




b


of the short arm


77


an end cap


80


in inserted to close the open tubing end. The opposite end


77




a


of the short arm


77


is preferably cut at an angle and is attached to pivot sleeve


69


of the pivot rod assembly


65


.




The pivot rod assembly


65


includes the pivot rod


66


and pivot sleeve


69


, as well as a locking spring


72


, a washer


73


, and a retaining nut


74


. The pivot rod assembly


65


provides a means for the pivot rod


66


to rotate relative to the pivot sleeve


69


and for the resulting articulation of the attached short arm


77


and the attached long arm


61


to stop when the arm assembly is in the extended position depicted in FIG.


6


. The cylindrical pivot rod


66


can have an end


66




a


attached to the angled end


61




a


of the long arm


61


. The pivot rod


66


extends through the open cylinder formed by the pivot sleeve


69


with each end


66




a


and


66




b


situated beyond the respective end of the pivot sleeve.




In the preferred embodiment, a locking pin


75


extends through a hole


67


bored through a midpoint along the pivot rod


66


, with the pin


75


situated adjacent end


69




a


of the pivot sleeve. The pivot rod


66


further includes an opposite threaded end


68


configured for receiving the retaining nut


74


. The nut is used to secure the washer


73


and locking spring


72


between the retaining nut


74


and the end


69




b


of the pivot sleeve


69


. In this arrangement, the locking spring


72


biases the pivot rod


66


toward the end


69




b


of the pivot sleeve. More specifically, the locking spring biases the pivot rod


66


so that the locking pin


75


can reside within notches


70


and


71


cut in oppose sides of the end


69




a


of the pivot sleeve


69


, as shown in FIG.


6


. When the locking pin


75


is so situated, the long arm


61


is fixed against rotation relative to the pivot sleeve


69


. Rotation is permitted when the pivot rod


66


is pushed toward end


69




a


of the sleeve


69


, against the force of the locking spring


72


, to thereby release the locking pin


75


from the notches


70


and


71


.




The long arm


61


can be constructed of a section of rectangular tubing of the same type as the short arm


77


. One end


61




a


of the long arm


61


is angled and attached to an end


66




a


of the pivot rod


66


. The other end


61




b


of the long arm


61


can be rotationally connected to the tablet plate


51


using rotational pin


59


, support disk


56


, a slotted washer


53


, and stop pin


55


. The long arm


61


can have an end cap


62


enclosing the tube end near the tablet plate


51


.




The arm


61


can define a thru-hole


63


sized to receive the rotational pin


59


therethrough. The pin


59


is preferably affixed to the underside of the tablet plate


51


, such as by press-fit into a corresponding bore in the plate. Most preferably, the pin passes through a support disk


56


interposed between the tablet plate


51


and the long arm


61


, and then through the hole


63


in the arm


61


. A retaining cap


64


can engage the pin


59


to fasten the rotational pin, while permitting the pin to rotate relative to the arm


61


.




In a further feature of this embodiment, the slotted washer


53


is preferably mounted to the long arm


61


, with the support disk


56


disposed between the washer


53


and the tablet plate


51


. The washer


53


defines a slot


54


along an arc of a constant radius and extending for less than 360-degrees around the washer. The slotted washer


53


is configured to cooperate with a stop pin


55


extending from the underside of the tablet plate


51


. In other words, the stop pin


55


rides within the slot


54


of the washer to control the range of rotational movement of the tablet plate


51


relative to the long arm


61


. Preferably, the slot


54


extends along an arc of about 135-degrees so that the user can find a comfortable orientation of the tablet plate in use. The tablet plate


51


can define multiple mounting holes


52


therethrough by which a work surface can be attached.




The operation of the chair tablet articulating arm assembly


50


is as follows. The stowed position


50


′ depicted in

FIG. 7

presents a well-situated location for the tablet when it is not in use. In the stowed position


50


′, the tablet plate


51


can be oriented in a vertical position, perpendicular to the chair seat. To re-position the tablet plate


51


to the first deployed position


50


″, depicted in

FIG. 8

, the tablet plate can be translated to the horizontal position, parallel to the chair seat, by the pivoting of the long arm


61


at the pivot rod assembly


65


, until the locking pin


75


engages the locking notches


70


and


71


. The tablet plate


51


is thereby located outside the chair arm


58


, at position


50


″ depicted in FIG.


8


.




To re-position the tablet plate


51


over the seat of the chair, such as in the second deployed position


50


′″ depicted in

FIG. 8

, the entire arm assembly can be simply rotated about the pivotable mounting fastener


79


located near the end of short arm


77


. Completion of the steps and movement of the assembly in reverse order can return the tablet plate to the stowed position


50


′ depicted in FIG.


7


.




While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character. It should be understood that only the preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.



Claims
  • 1. A tablet arm apparatus for supporting a work surface on an article of furniture, the apparatus comprising:a mounting bar having a first arm and a substantially perpendicularly disposed second arm; a clamp having a portion attached to said second arm and configured to engage a member of the article of furniture to support said tablet arm apparatus thereon; a pivot hub rotatably mounted on said first arm of said mounting bar; a tablet plate configured for supporting the work surface and including at least one mounting ear; and means for pivotably attaching said at least one mounting ear to said pivot hub to permit pivoting of said tablet plate relative to said pivot hub, whereby said tablet plate is also rotatable with said pivot hub relative to said mounting bar.
  • 2. The tablet arm apparatus according to claim 1, wherein:said tablet plate includes two mounting ears defining a U-shape opening to receive said pivot hub therebetween; and said means for pivotably attaching includes; a pair of pin bores defined in said pivot hub at opposite sides thereof; and a pair of pins, one each projecting from a corresponding one of said two mounting ears and pivotably disposed within a corresponding one of said pair of pin bores.
  • 3. The tablet arm apparatus according to claim 2, wherein:said pivot hub defines a central opening therethrough for rotatably mounting said pivot hub on said first arm; said pin bores intersect said central opening; said first arm of said mounting bar defines at least a pair of oppositely disposed detents; and said pins are spring pins configured for spring biased engagement within a corresponding one of said detents when said tablet plate and pivot hub are rotated to a position in which said pins are aligned with said detents.
  • 4. The tablet arm apparatus according to claim 1, wherein said clamp includes:a first C-clamp portion attached to said second arm and defining a first cylinder portion; a second C-clamp portion defining a second cylinder portion, whereby said first and second cylinder portions can be juxtaposed about the member of the article of furniture; and a number of fasteners for clamping said first and second C-clamp portions together with said first and second cylinder portions engaged about the member of the article of furniture.
  • 5. The tablet arm apparatus according to claim 1, further comprising a rest bracket mounted on said first arm adjacent said pivot hub, said rest bracket defining a surface for supporting said tablet plate when said plate is in a deployed position.
  • 6. The tablet arm apparatus according to claim 1, wherein said pivot hub is composed of a low-friction material.
  • 7. A tablet arm apparatus for supporting a work surface on an article of furniture, the apparatus comprising:a first arm having a first end and an opposite second end, said second end defining means for pivotably mounting said first arm to the article of furniture; a second arm having a first end and an opposite second end; a tablet plate mounted to said second end of said second arm; a pivot rod assembly including a pivot sleeve and a pivot rod rotatably disposed within said pivot sleeve, wherein the first end of one of said first arm and said second arm is connected to said pivot sleeve, and the first end of the other of said first arm and said second arm is connected to said pivot rod; wherein at least one notch is defined at one end of said pivot sleeve; and wherein a locking pin is mounted on said pivot rod and is configured to be received within said at least one notch to prevent relative rotation between said pivot rod and said pivot sleeve.
  • 8. The tablet arm apparatus according to claim 7, wherein:said pivot rod has a first and an opposite second end, with said locking pin disposed adjacent to said first end of said pivot rod and said one end of said pivot sleeve; said pivot rod being rotatably and slidably disposed within said pivot sleeve; and said pivot rod assembly further includes a biasing spring acting between said second end of said pivot rod and an end of said pivot sleeve opposite said one end and operable to bias said locking pin into said at least one notch when said pivot rod is rotated relative to said pivot sleeve to a position in which said locking pin is aligned with said at least one notch.
  • 9. A tablet arm apparatus for supporting a work surface on an article of furniture, the apparatus comprising:a first arm having a first end and an opposite second end, said second end defining means for pivotably mounting said first arm to the article of furniture; a second arm having a first end and an opposite second end; a tablet plate mounted to said second end of said second arm; a pivot rod assembly including a pivot sleeve and a pivot rod rotatably disposed within said pivot sleeve, wherein the first end of one of said first arm and said second arm is connected to said pivot sleeve, and the first end of the other of said first arm and said second arm is connected to said pivot rod; a washer affixed to said second end of said second arm, said washer defining an arcuate slot therein; means for rotatably fastening said tablet plate to said second end of said second arm; and a stop pin projecting from said tablet plate and into said arcuate slot, whereby said arcuate slot limits the range of rotation of said tablet plate relative to said second arm.
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Number Name Date Kind
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4216994 Benoit Aug 1980 A
4591206 Pribble May 1986 A
4848833 Grall Jul 1989 A
4852940 Kanigowski Aug 1989 A
4861102 Fuller Aug 1989 A
5139309 Kornreich Aug 1992 A
5169210 Fricano Dec 1992 A
5683136 Baumann et al. Nov 1997 A
5765911 Sorenson Jun 1998 A
5845964 Poon Dec 1998 A
5865124 Wroe Feb 1999 A
D409860 Best May 1999 S
5931528 Shields Aug 1999 A