CA2002028C

CA2002028C - Vertically adjustable retrofittable workstation

Info

Publication number: CA2002028C
Application number: CA002002028A
Authority: CA
Inventors: Edward Malcomb Schwartz; Robert Elliott Morgan; Wilburn D. Everman
Original assignee: Edtech Co
Current assignee: Edtech Co
Priority date: 1988-11-08
Filing date: 1989-11-01
Publication date: 1992-08-25
Anticipated expiration: 2009-11-01
Also published as: EP0368186A2; DE68914092D1; US4881471A; EP0368186A3; CA2002028A1; JPH02220606A; AU4432989A; EP0368186B1; KR900007367A; AU627240B2

Abstract

ABSTRACT OF THE DISCLOSURE

A vertically adjustable, retrofittable work station including a first pair of vertically oriented spaced rails having engaging teeth protruding therefrom so as to be stationarily mounted on an existing wall panel of a conventional work station, a second pair of vertically oriented rails individually, slidably, interlockingly disposed in the first pair of rails, a pair of support brackets having engaging teeth protruding therefrom so as to be individually mounted on the second pair of rails, a work surface supported by the support brackets, a pair of interconnecting channels for respectively interconnecting the first and second pairs of rails, and a drive mechanism coupled between the interconnecting channels to move the channels toward or away from each other so as to attendantly displace the work surface.

Description

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A VERTICALLY ADJUST~BLE. RETROFITTABL~ WORKST~TION

Field Of The Invention The invention relates to a device for retrofitting a work station such that the work surface can be automatically vertically adjusted to ac~ommodate workers of different heights.

Background Of The Invention There are at lea~t 10 million video display terminals (hereinafter referred to as VDT s) in use across the country, and it is predicted that there will be at least 40 million VDT' 8 by the end of this decade. While VDT s are u~ed for a variety of tasX~, they are used most intensively by a range of office workers who may spend the entire day key-punching and processing information. VDT s have been in~trumental in increasing productivity and efficiency for virtually every major industry, and will continue to play a central role in thi~ country's economy.
However, as the number of VDT 8 in the worX
place ha~ risen, so have the health complaints associated with their use. Surveys indicate that a majority of full-time VDT users report high frequencies of health problems. Among other problems, recent ~tudies confirm that VDT users have higher incidences of problem~ ~uch as eye strain, headaches, insomnia, back and neck strain and fatigue.
As these health concerns have been recognized as legitimate and serious, ~teps are being taken in at lea~t twenty ~tate~ to introduce legi~lation to institute health and safety protections for VDT

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, users. ~hile questions have been raised regarding whether VDT's emit harmful radiation, studies show that the radiation levels emitted by the VDT ' s are well below levels naturally found in the environment. Thus, it is generally concluded that radiation is not the primary cause of the physical problems discussed above. In contrast, numerous studies have indicated that operator injury such as carpal tunnel syndrome and tenosynovitis, which are cumulative trauma injuries, are caused by improper VDT workstation design.
In particular, the conventional VDT workstation is designed such that the work surfaces cannot be adjusted to accommodate people of different height. Shorter people must arch their body and elevate their arms in order to properly operate the keyboard and view the display terminal. In contrast, taller people have to hunch over to access the keyboard and view the terminal.
Accordingly, the conventional VDT work stations have resulted in a high frequency of health-related problems.

It is an object of this invention to provide a retrofitting device for retrofitting an existing work station such that the work surface can be rapidly and automatically vertically adjustable.
It is a further object to provide a retrofitting device for retrofitting an existing work station such that the work surface can be vertically adjusted while the video display terminal is disposed thereon.
A further object is to provide an inexpensive retrofitting device for retrofitting a standard work station with a vertically adjustable work surface without requiring a redesign of the existing work station.
These and other objects, which will become apparent from the ensuing description of the preferred embodiment of the invention, are provided according to the present invention by a vertically adjustable, work station ,.;, -.
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~36)2~8 adapted to be mounted to a wall panel, the wall panel having a pair of horizontally spaced, vertically oriented support rails secured thereto, said work station comprising: a pair of horizontally spaced, vertically oriented support rails secured to said panel; a work surface; a pair of support brackets for supporting said work surface; a first pair of elongate, vertically oriented, rails horizontally displaced from one another and adapted to be individually and stationarily mounted to the support rails; a second pair of elongate, vertically oriented, rails individually slidably mounted to said first pair of rails; means for individually mounting said support brackets and thus said work surface to said second pair of rails; a first elongate, horiæontally oriented, channel member interconnecting said first pair of rails; a second elongate, horizontally oriented, channel member interconnecting said second pair of rails; and drive means coupled between said first and second channel members for selectively displacing said channel members towards or away from each other to attendantly vertically displace the work surface.
In accordance with another aspect of the present inven-tion, there is also provided a vertically adjus~able, work station adapted to be mounted to a support means, the support means having a pair of horizontally spaced, vertically oriented support rails secured thereto, said work station comprising: a work surface; a pair of support brackets for supporting said work surface; a first pair of elongate, vertically oriented, rails horizontally displaced from one another and adapted to be individually and stationarily mounted to the support rails; a second pair of elongate, vertically oriented, rails individually slidably mounted to said first pair of rails; means for individually mounting said support brackets and thus said work surface .

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2~:328 to said second pair of rails; a first elongate, horizontally oriented, channel member interconnecting said first pair of rails; a second elongate, horizontally oriented, channel member interconnecting said second pair of rails; and drive means coupled between said first and second channel members for selectively displacing said channel members towards or away from each other to attendantly vertically displace the work surface.

BRIEF DESCRIPTION OF THE D:RAWINGS
Preferred embodiments of the invention will now be described in greater detail and will be better understood when read in conjunction with the ~ollowing drawings in which:
Figure 1 is a perspective view of the conventional VDT workstation;
Figure 2 is a front view of the vertically adjustable, retrofittable workstation of the present invention;
Figure 3 is a side view of the vertically adjustable workstation of the invention;
Figures 4, 5 and 6 are sectional views taken along the lines IV-IV, V-V and VI-VI of Fiyure 2, respectively;
Figures 7, 8 and 9 are sectional views taken along the lines of VII-VII, VIII-VIII, and IX-IX of Figure 2, respectively; and Figure 10 is a sectional view taken along the line X-X of Figure 2.

DESCRIPTION OF PREFERRED EMBODIMENTS
Figure 1 illustrates the conventional video display terminal work station. As shown in Figure 1, the conventional work station includes a plurality of interconnected panels 1 which serve as support means having a plurality of elongate vertically extending support rails 2. Each of the support rails 2 includes a "

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2~Z~3 plurality of slots disposed along the vertical length thereof. Support brackets 3, having a plurality of teeth protruding therefrom, are secured to the support rails 2 by inserting the teeth of the support brackets into the complimentary corresponding slots of the support rails 2.
The work surface 4 is supported by a pair of the supporting brackets 3.
Thus, while the conventional work surface is vertically adjustable, such vertical adjustment can only occur by disassembling the table top from the brackets and vertically adjusting the location of the support brackets on the support rails. Accordingly, to vertically adjust the conventional work surface it is necessary to remove all items therefrom, including the video display terminal. It is there~ore not practical to adjust the height of the work surface on an hourly or daily basis to accommodate a change in shift of workers of different heights. Therefore, rapid, automatic, vertical adjustment of the work surface is not possible resulting in an unhealthy working environment.
The retrofittable device of the invention is a vertically adjustable unit which is designed to be mounted on the existing support rails 2 and to support the existing support bracket 3 for supporting the work surface 4 in a vertically adjustable manner.
Particularly, as shown in Figs. 2 and 3, the retrofittable device of the invention comprises a pair of stationary rails 5 adapted to be mounted on the existing support rails 2, a pair of slidable : , ~ , ~ ~ .. .

rail~ 6 individually slidably disposed on the stationary rails 5, a slidable channel 7 connecting each of the slidable rails 6, a fixed channel ~
connecting each of the stationary rails 5, a support bracket 3 for supporting the work surface 4 and a driving mechanism coupled to the slidable 7 and fixed channel 8 for selectively displacing the channels toward~ or away from each other to attend~ntly vertically displace the work surface 4.
Referring to Fig. 3, the ~tationary rails 5 are vertically extending elongate members for securing the retroflttable device to the ~upport rails 2 of the exi~ting panel. In cro3s-section, the stationary rails 5 are substantially G-shaped as shown in Figs.
5 and 6. Secured to each of the stationary rails 5 is an elongate securing plate 9 extending the length of the stationary rail 5. A~ shown in Fig. 3 the securing plate 9 ha~ a plurality of engaging teeth lO
extending therefrom along the vertical length of the stationary rail S. The teeth are shaped and arranged to correspond to the 3hape and arrangement of the teeth extending from the existing support bracket 3.
Thus, the teeth lO of the securing plates 9 are insertable into the ~lots 11 of the existing vertical support rails 2 in the same manner that the support bracket~ 3 are conventionally insertable into the slot~ 11 of ths ~upport rails ~o as to allow for the ~tationary rails 5, and hence the retrofittable device, to be ea~ily mounted to the existing rails 2.
The slidable rails 6 are also G-shaped in cross-sections to correspond to the shape of the stationary rails 5 such that slidable rails 6 are individually ~lidably accommodated in the stationary : : .

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rails 5 in the manner ~hown in Fig~. 3, 5 and 6. To allow for ~liding movement between the slidable rails 6 and the stationary rail~ 5, a pair of sliding bushings 12 are secured to each of the slidable rail~ 6 at upper and lower portions thereof. Each of the bushing~ 12 comprise a pair of L-shaped substantially frictionle~ members 13 314 which are interconnected such that one of the frictionless member~ 13 i~ disposed on the inside of the G-shaped slidable rail 6 while the other frictionless member 14 is disposed on the outside of the G-shaped slidable rail 6. The frictionles~ member~ 13,14 are connected by dowel pin3 15, screws or the like to the slidable rails 6. Thu~, the frictionles~ members are fixedly attached to the slidable rail~ 6 so as to slide therewith relative to the stationary rail~ 5 to allow for ~mooth vertical adjustment of the 61idable rails 6.
As shown in Figs. 2 and 3, each of the slidable rails 6 has a plurality of 810t8 16 disposed along the length thereof. The slot~ 16 are shaped and arranged in the ~ame manner as the slot~ 11 provided in the existing ~upport rails 2. Accordingly, the existing ~upport brackets 3 can be secured to the slidable rails 6 in the conventional manner by in~erttng the teeth 17 of the ~upport bracket~ 3 into the complimentary slots 16 of the slidable rails 6.
The 31idable channel 7 and fixed channel 8 respectively interconnect the slidable rail~ 6 and the stationary rails 5, a~ illuatrated in Fig. 2.
That .8, the slidable rails 6 are interconnected by the ~lidable channel 7 and the stationary rails 5 are interconnected by the fixed channel 8. The : .:, : , , , - .. :
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channel~ 7,8 are dimensioned in length ~uch that the overall width of the retrofittable device correspond~
to the standard distance between existing support rails 2 in conventional work stations. For example, the distance between the ~upport rai 18 in standardized work stations i8 either 48 or 64 inches.
Correspondingly~ the channel~ are dimensioned such that the distance between the stationary rails i8 either 48 inchee or 64 inches such that the retrofittable device can be used to retrofit any standard size work station.
The cross-sectional shape of each of the channels 7,8 is in the form of a "W" resulting in a high bending strength with a minimal weight. The slidable channel 7 and stationary channel 8 are respectively connected to the slldable rails 6 and the statlonary rails 5 in the manner shown in Figs. 2, 5 and 6. Specifically, each of the stationary rails S and slidable rails 6 include a pair of U-shaped connector links 18 extending perpendicularly therefrom. Referring to Fig. 4, the slidable rail 6 and stationary rail 5 are respectively ~ecured to the slidable channel 7 and fixed channel 8 by respectively ~ecuring the pair of connector links 18 to the outer correspondingly U-shaped portions 19 of the W-shaped channels using ~crews o~ the like.
As shown in Figs. 1 and 3, the support bracket~

3 are sub~tantially L-shaped member~ having a plurality of teeth 17 protruding therefrom. The teeth 17 are engageable with the slots 16 of the ~lidable rails 6 ~uch that the ~upport brackets 3 extend perpendicularly from the slidable rails 6 away -~ - 9 from the existing panel 1 to support the work surface 4 thereon.
Having fully de~cribed the overall structure of the retrofittable device, the driving and guide mechani~m for selectively displacing the channels toward or away from each other to attendantly displace the work surface will be described hereinafter.
Referring to Figs. 2 and 7-10, the driving/suide mechani~m generally includes a slide plate 20, a drive ~crew 21 and a motor 22 secured to the slidable channel 7 as well as a drive nut 23 and a bearing bracket 24 fixedly attached to the fixed channel 8.
Thc slide plate 20 i~ a ~ubstantially U-shaped plate which i~ fixedly secured to the slidable channel 7 at the top end of the ~lide plate 20 and which extends vertically downwardly therefrom. The slide plate 20 includes two flange~ 25 on opposing side thereof to which linear bearings 28 are individually attached.
In particular, the linear bearing~ 28 are substantially rectangular in cross-section and include a ~lot extending longitudinally thereto in which the flanges are respectively secured. The linear bearing~ 28 are individually secured to the 1anges 25 using a plurality of dowel pin 29 in~erted into allgned holes in the linear bearing and the flange, a~ ~hown in Fig. 9. Of course, the linear bearing could be ~ecured to the flange by any suitable manner. The 11near bearings 28 are in sllding engagement with the bearlng bracket in the manner de~cribed hereinafter.
The motor 22 i8 fixedly ~ecured to the ~lidable channel 7 and includes the rotatable drive ~crew 21 ~:'. . : : : ~ , - -, : :

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extending vertically downwardly therefrom. The drive screw 21 i8 threadedly engag~d with the drive nut 23 which is fixedly secured to the stationary channel 8 in the following manner.
A substantially U-shaped vertically extending cover 26 is secured to the stationary channel as shown in Figs. 2, 9 and 10. The cover 26 extends downwardly a sufficient distance to cover the drive mechanism. Secured to the interior portion of the cover is a U-~haped inner bracket 27 for securing the drive nut 23 and the bearing bracket 24.
Specifically, the drive nut 23 is secured to the interior portion of the inner bracket 27 u~ing screws or the like. The drive nut 23 i~ oriented such that the axis of the threaded hole extends in the vertical direction to receive the drive screw 21.
The bearing bracket 24 is secured to the inner bracket 27 a~ ~hown in Fig. 8. The bearing bracket 27 i~ substantially C-shaped and extends in the vertical direction. The outer portions of the bearing bracket are dimensioned to slidably receive the linear bearings 28 individually secured to the flange~ 25 of the ~lide plate 20 in the manner described hereinabove. In this manner, the slide plate 20, in sliding contact with the bearing bracket 24, distributes the torsional force resulting from the torque of the drive ~crew to prevent any di~tortion of the device.
Accordingly, upon rotation of the drive screw, the slidable channel, and attendantly the slidable rails and the work ~urface, move~ in the vertical direction to thereby ad~ust the elevation of the work surface.

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A top cover 30 i~ provided above the work ~urface, as shown in Fig. 3. Specifically, th~ top cover 30 i~ connected at opposing lateral sides to the top of each slidable rail 6 and extends downwardly just below the work ~urface 4. Disposed on the top cover is the elevation adjustment switch 31 for selectively operating the motor to vertically displace the work surface to the desired elevation.
Al30 dispo~ed on the upper cover are the necessary VDT hook-up connections 32 as well as an electrical outlet 33. In addition, a lower skirt is disposed below the work surface to cover the portion of the drive mechani~m which i8 not covered by the cover 26.
Having fully described the details of the invention, the retrofit procedure will be described hereinafter. Referring to Figure 1, the de~k top ll and the existing support brackets 3 are removed from the exi~ting vertical ~upport rail~ 2. TherPafter, as illustrated in Fig. 3, the retrofittable device is attached to the existing rail 2 by securing the engagement teeth 10 of each of the stationary rail~ 5 into the slots of the exi3ting support rails 2.
While the desk top can be automatically adju~ted by a distance of twelve inches u~ing the automatic drive mechanism, the retrofittable device can be secured at any elevation along the existing rails.
For instance, the ~tandard table top height i~
30-1/4". Thu~, it may be desirable to attach the retrofittable device to the exi~ting rails ~uch that the table top can be adju~ted six inche~ in both the ; up and down direction with re~pect to the ~tandard 30-1/4" table top height; thu~, the table top can be automatically adju~ted ~rom 24-1/4" to 36-1/4".

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Having ~ecured the retrofittable device to the existing panel 1, the exi~ting ~upport bracXets 3 are attached to the slidable rails 6 of the retrofittable device in the ~ame manner that the support bracket~ 3 and normally attached to the existing rails 2. That is, the engagement teeth 17 of the existing support brackets 3 are inserted into the slots 16 of the slidable rail~ 6 ~o as to be securely attached thereto. It should be noted that the support brackets 3 can be attached at various elevation~
along the slidable rail~ 6 providing an additional adjusting feature. Once the upport brackets are attached to the sliding bracket~, the table top 4 i~
placed on top of the ~upport bracket~ 3 in the usual manner.
Although the pre~ent invention describes the preferred embodiment of khe invention, it should be under~tood that numerous modification~ and adaptations may be resorted to without departing from the ~pirit of the invention. For instance, an emergency cut-off switch may be provided to prevent accidental vertical movement of the work ~urface.
Thus, the retrofittable work ~tation according to the invention provides a solution to the problems a~ociated with the conventional work station~
discus~ed hereinabove. While the conventional work station~`included substantially fixed, non-adjustable work surface~ resulting in stre~ related health problem~ for the VDT u~er~, the invention provides a retrofittable work ~tation having an automatically ad~ustable work surface to accommodate u~er~ of various heights to thereby provide a comfortable, substantiaLly ~tress free working environment.

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Claims

1. A vertically adjustable, work station adapted to be mounted to a wall panel, the wall panel having a pair of horizontally spaced, vertically oriented support rails secured thereto, said work station comprising:
a) a pair of horizontally spaced, vertically oriented support rails secured to said panel;
b) a work surface;
c) a pair of support brackets for supporting said work surface;
d) a first pair of elongate, vertically oriented, rails horizontally displaced from one another and adapted to be individually and stationarily mounted to the support rails;
e) a second pair of elongate, vertically oriented, rails individually slidably mounted to said first pair of rails;
f) means for individually mounting said support brackets and thus said work surface to said second pair of rails;
g) a first elongate, horizontally oriented, channel member interconnecting said first pair of rails;
h) a second elongate, horizontally oriented, channel member interconnecting said second pair of rails;
and i) drive means coupled between said first and second channel members for selectively displacing said channel members towards or away from each other to attendantly vertically displace the work surface.

2. A vertically adjustable work station adapted to be mounted to a support means, the support means having a pair of horizontally spaced, vertically oriented support rails secured thereto, said work station comprising:
a) a work surface;
b) a pair of support brackets for supporting said work surface;
c) a first pair of elongate, vertically oriented rails horizontally displaced from one another and adapted to be individually and stationarily mounted to the support rails;
d) a second pair of elongate, vertically oriented rails individually slidably mounted to said first pair of rails;
e) means for individually mounting said support brackets and thus said work surface to said second pair of rails;
f) a first elongate, horizontally oriented channel member interconnecting said first pair of rails;
g) a second elongate, horizontally oriented channel member interconnecting said second pair of rails; and h) drive means coupled between said first and second channel members for selectively displacing said channel members towards or away from each other to attendantly vertically displace the work surface.

3. The work station of claims 1 or 2, wherein each of said support rails includes one of a plurality of slots and a plurality of teeth-like protrusions vertically disposed therealong and each of said first rails includes another of said plurality of slots and said plurality of teeth-like projections vertically disposed therealong wherein said protrusions are insertable into said slots to stationarily individually mount said first pair of rails to said support rails.

4. The work station of claims 1 or 2, wherein each of said second rails includes one of a plurality of slots and a plurality of teeth-like protrusions vertically disposed therealong and each of said support brackets includes another of said plurality of slots and said plurality of teeth-like projections vertically disposed therealong wherein said protrusions are insertable into said slots to stationarily individually mount said support brackets to said second rails.

5. The work station of claims 1 or 2, wherein said drive means comprises:
an elongate vertically extending drive screw rotatably secured to one of said first and second channel members;
a threaded nut fixedly secured to another of said first and second channel members, said drive screw being threadedly engaged with said nut; and means for rotating said drive screw relative to said nut such that said drive screw and said nut move toward or away from one another to attendantly vertically displace the work surface.

6. The work station of claims 1 or 2, wherein each of said rails of said first and second pairs of rails are substantially C-shaped and wherein said second pair of rails are individually slidably interconnected to said first pair of rails with a substantially frictionless member interlocked therebetween.

7. The work station of claim 1, further comprising a slide support for providing support to said first and second channel members when said channel members are driven by said drive means.

8. The work station of claim 2, further comprising a slide support for providing support to said first and second channel members when said channel members are driven by said drive means.

9. The work station of claims 7 or 8, wherein said slide support comprises:
a vertically oriented slide plate fixedly connected to one of said first and second channel members and having flanges on opposing sides thereof;
a substantially frictionless member fixedly connected to each of said flanges;
a vertically oriented bearing bracket fixedly connected to another of said first and second channel members and having receiving portions on opposing sides thereof, said frictionless members being individually slidably disposed in said receiving portions of said bearing bracket so as to distribute the torsional forces associated with said drive means such that said first and second members can be smoothly, vertically displaced from one another.