US 2310346 A
Description (OCR text may contain errors)
Feb. 9,1943. AB. BELL f 2,310,346
DRIVER S CHAIR l Feb. 9, 1943. BBELLl 2,310,346
DRIVERS CHAIR Filed Dec. 26; 1959 2 Sheets-Sheet 2 Patented Feb. 9, 1943 DRIVERS CHAIR Alfred B. Bell, Gardner, Mass., assig'nor to Heywood-Wakefield Company, Gardner, Mass., a corporation of Massachusetts Application December 26, 1939, Serial No. 310,891
This invention relates to an adjustable chair adapted for use as a bus drivers seat or for other equivalent uses.
Drivers of vehicles such as motor busses customarily occupy the drivers seat for consider-V able period of time when on duty. It is important that the seat and its back be so arranged as to support the driver in a natural and comfortable position. A strained or awkward position of the driver results in fatigue which increases the danger of accidents. Since a motor bus may be operated by diierent successive drivers, it is desirable that the drivers chair be adjustable to accommodate drivers of different sizes.
It is an object of the invention to provide a chair with improved means for effecting various adjustments quickly and easily.
For a more complete understanding of the invention, reference may be had to the following description thereof, and to the drawings of which- Figure l is a side elevation of a chair embodying the invention, portions being broken away to show in section.
Figure 1a is a fragmentary sectional view on the line Ia-Ia of Figure 1.
Figure 2 is a fragmentary section on the line 2--2 of Figure 1.
Figure 3 is a perspective view of parts of the chair by which the back is supported.
Figure 4 is a section on the line 4--4 of Fig ure 1.
Figure 5 is a perspective view of the stem which supports the seat.
Figure 6 is a section on the line 6--6 of Figure 4.
Figure 7 is a fragmentary sectional view of a portion of the structure shown in Figure 6, the parts being shown in a diierent position of op eration.
Figure 8 is a section on the line 8--8 of Figure l. y
Figure 9 is a fragmentary sectional view of a modified form of the invention.
The chair illustrated in the drawings is provided with a stationary pedestal I0 adapted to be secured to the floor of a vehicle. As illustrated in Figure 4, the upright portion of the pedestal I0 is generally cylindrical and is made f with a central cylindrical bore in which is slidable a stem I2. The upright of the pedestal is also provided with a pair of parallel auxiliary bores I4 and I8 which are connected to the central bore by slots 20 and 22, these slots being for the purpose of slidably receiving a pair of splined elements 24 and 26 which are elongated as indicated in Figure 5 to extend substantially the entire length of the stem I2 and which are rigidly secured to the stem, the stern having shallow longitudinal grooves formed in its side wall at opposing points to receive these splines as indicated in Figures 4 and 5. The spline elements 24 and 25 may be permanently secured to the stem in any suitable manner such as by screws, welding or the like. The pedestal I0 is preferably surrounded by a protective and ornamental housing 28. The stem I2 supports the seat of the chair and is vertically adjustable to adjust the height of the seat. To this end suit-- able notches are cut in the side wall of the stem to form ratchet teeth by which the stem and the seat mounted thereon can be maintained at different heights as desired. The stem I2 is preferably hollow as indicated in Figures 4 and 5 and is preferably formed with a relatively thin wall to minimize weight and cost. The notches which are cut in a vertical series to form the ratchet teeth penetrate the wall of the stem and form apertures therethrough. The lowermost notch 3i) is longer than the upper notches 32. The notch 30 also differs from notches 32 in that it forms upper and lower horizontal shoulders 34 and 36, whereas each of the notches 32y has an upper shoulder 38 which is horizontal and a sloping lower shoulder 4U. Cooper-ating with these notches, the shoulders of which are equivalent to ratchet teeth, is a pawl 42 which projects through a suitable aperture in the side wall of the pedestal II) and is arranged to enter any one of the apertures formed by the notches in the stem. As shown in Figure 6, the pawl 42 is provided with a nose 44 which has a horizontal top surface and an inclined lower surface so that the nose is tapered. This nose is adapted to fit into any of the notches 32 so that its lower` inclined face rests against the shoulder 40. In each of the upper notches 32, the shoulders 3E and 4i) are spaced in such a manner as to receive the tapered nose only of the pawl 42. Thus the pawll can project into the notches 32 only to the extent indicated in Figure 6. It is thus evident that, if the stem be raised, the inclined surface of the nose 44 will be acted upon by the inclined shoulder 4) with which it is engaged to push the pawl 42 outward so as to permit upward movement or' the stem and the seat which it supports The lowermost notch 30, however, has an aperture through the wall of the stem large enough to receive the full cross section of the pawl 42,
so that when the notch 30 is in register with the pawl the nose of the pawl may project entirely beyond the wall of the stem so as to be entirely within the stem as indicated in Figure 7. Since the lower shoulder 3S is horizontal and is arranged to engage the horizontal bottom face of the shoulder when the tapered nose is entirely within the stem, removal of the stem from the bore in the pedestal is prevented unless the pawl be nrst retracted from the notch 39. The pawl @2 is pivotally attached to a rocking lever 53 which is rockably mounted as at 52 between a pair of ears 54 secured to the pedestal I9. A treadle element 56 projects outward through the housing 28 and is arranged in such a manner as to retract the pawl 42 when the treadle is depressed. A stop element 58 is preferably provided on the lever U to prevent excessive retraction of the pawl 42 such as might move it clear of the pedestal wall. A suitable compression spring G is shown on the drawings for the purpose of pressing the pawl 42 resiliently inward, so that when the treadle 5E is released the pawl tends to press into whichever notch is in n; gistry therewith.
Instead of using a lever 59 to retract the pawl ft2, a simple stem 5I may be employed, such stem being attached to the pawl l2 and having a convenient handle 53 at its outer end whereby the occupant of the chair can readily retract the pawl 42 from whatever notch it may be engaged in. To press the pawl inward, a compression spring 55 may be provided thereon, a housing 57 being located around the stein to take the thrust of the spring 55. The inner end of the spring bears on the pawl 4Z.
In order to facilitate vertical adjustment of the seat, a portion of the weight thereof may be taken by a suitable compression spring 62 located inside of the stem I2, the upper end of this spring bearing against a transverse plate Sli which is secured within the stem. The loweil end of the spring 62 may bear against a plate EE which is xed to the pedestal IG at the bottom of its cylindrical bore.
A shield E5 is provided within the bore of the pedestal to prevent interference between the spring G2 and the pawl d2. This shield may also serve as a stop to limit the inward movement of the pawl when its nose enters the lowermost aperture 39. As indicated in Figures 4 and 5, the shield 65 may conveniently be a portion of a cylinder which is secured within the stem I2 by any suitable means, such as welding.
The operation of the foregoing portion of the chair is simple. If it is desired to elevate the seat, the seat is manually raised to the desired height, the pawl being successively pushed out of the upper notches 32 by engagement with the inclined shoulders 49. If the seat is moved to its highest position of adjustment, the nose 44 of the pawl projects through the lowermost notch 39 so as to be entirely within the bore of the stern i2. Further upward movement of the chair and stem is thereupon prevented by engagement of the lower shoulder 36 of the notch 33 with the horizontal bottom face of the pawl 2. If removal of the seat and stem from the pedestal is desired, it is only necessary to step on the treadle 5S so as to retract the pawl from the notch 3S, whereupon the seat and steml can be lifted clear. In order to lower the seat, the treadle 55 must be pressed to permit the upper notches 32 to move down past the retracted nose of the pawl.
Mounted on the upper end of the stem |2 are a pair of parallel rails extending horizontally and connected by suitable transverse members 72, 'f4 and 76. Slidably mounted on these rails 5 is a horizontal skeleton platform or frame 89 which is held thereon by pin-and-slot connec tions 8| which permit sliding movement of the platform in a front-torear direction on the rails 19. The platform 89 is provided with a bearing member 82 for a screw-threaded shaft 84, on the forward end of which is a convenient oper-- ating handle 86. The threaded shaft 84 extends rearwardly from the handle 86 and is in threaded engagement with the transverse member 1B. Rotation of the threaded shaft 84 thus results in a forward or rearward movement of the platform 89. Bolted or riveted to the side margins of the platform 89 are a pair of longitudinal bars 88 to the ends of which is welded a tubular member Si). As indicated in Figure 8, this tubular memberv has a transverse front portion, side portions parallel to the bars 88, and rear portions which are connected by a member |60, hereinafter referred to. From the side portions of the tubular frame member 90 a pair of extensions 92 branch off and curve upwardly to serve as supports for the back rest of the chair.
Hinged as at 94 to the forward portion of the tubular frame 99 is a seat-cushion frame SG on which is directly mounted the seat cushion 98.
The seat cushion and its frame are thus rockable on the hinge 94 to adjusted positions as indicated by broken lines in Figure 1. These difierentpositions are characterized by different degrees of elevation of the rear end of the seat cushion. In order to support the seat cushion in such adjusted positions, the member |99 which connects the ends `of the tubular member 90 is provided with a number of suitable apertures |92. A pawl |84 is mounted on the bottom of the seat'frame 9S for longitudinal sliding movement in such a direction as to engage the fixed member |99 as indicated in Figure 1. A suitable compression spring |06 presses the tapered nose |93 of the pawl against the member |90, the pawl and spring being housed in a casing IIl'I which is secured by a pair of brackets |99 to the seat frame 96. A pair of hand grips III] may be mounted on the sides of the seat cushion 93 to facilitate lifting the rear portion of the seat cushion. When the seat 98 is rocked on its hinge so that its rear end is elevated, the nose |08 on the pawl |94 slides upward against the face of the member |99 until it registers with one of the apertures |92. Thereupon the spring |06 pushes the tapered nose into such aperture. The upper surface of the nose is inclined, so that, if the lifting is continued, the nose will be forced out of the opening |62 and will snap into the next opening when the pawl comes into registry therewith. The lower surface of the nose |08 is not inclined so that the seat is held in adjusted position by the pawl |94 until the pawl is retracted to permit the rear end of the seat to descend. For convenient retraction of the pawl |94, a rockshaft |I2 is mounted on the seat frame 96. A finger H4 projects radially from the shaft I| 2 into a suitable notch in the pawl, so that if the shaft is rocked in the proper direction the finger |I4 will retract the pawl |94. The shaft I I2 projects out to one side ofthe seat cushion 98 and is provided with an operating lever IIS. This lever projects forward from the shaft I |2 so that its end portion is convenient to the hand of the operator and can be easily grasped to rock the shaft and release the pawl from the openings |02.
A seat-back |20 is releasably supported on the uprights 92 and can be adjusted thereon to various angles of inclination. To this end, a shallow housing member |22 is secured to each side edge of the seat-back |20. Each housing member, as illustrated in Figure 3, is elongated and is provided with a slot |24 near its lower end and a branch aperture near its upper end. This aperture, as shown, may consist of a circular hole |26 from which a slot |28 extends upward and branches into three recesses or notches |30, |32 and i3d. On each upright 92 is an upper pin i439 and a lower pin |42. rIhe pins on each upright project toward the other upright and each upper pin |40 is provided with a head M4 adapted to enter the hole |26 on the corresponding housing member |22. The slot |28 and its branches are wide enough for the pin |40 but are narrower than the diameter of the head |44 so that as long as the pin |40 is kept in the slot |28 or any of its branches, the housing |22 is locked to the upright 92. As indicated in Figure 2, the lower pin |42 projects through the slot |24 and also through a hole |48 in the upper end of a plunger |50. This plunger extends down within the housing member |22 through a hole in the lower wall of the housing member. A compression spring |52 is carried by the plunger |50 and presses downward through a loose washer |53 against the lower wall of the housing member |22. The two springs |52 thus tend to push the seat-back |20 downward, as-
sisting force of gravity. Since the pins |40 and |42 ride in slots, the seat-back can be manually raised a limited distance against the force of gravity and the pressure of the two springs |52. By raising the seat-back, the upper pins |40 are caused to ride out of the branch notches in which they have been seated. The seat-back can thus be tilted so as to permit the pins |40 to enter other notches, thus holding the seatback in a different angle of inclination. In the embodiment of the invention illustrated on the drawings, three possible angles of inclination for the seat-back are provided since each housing member has a slot with three branches or notches. If desired, a greater or lesser number of notches can be provided.
It is evident that various modications and changes may be made in the embodiment of the invention herein shown and described without departing from the spirit or scope thereof as defined in the following claim.
A chair of the class described, comprising a stationary upright pedestal having a vertical bore therein, a hollow cylindrical stem slidably mounted in said bore, spline means preventing rotation of said stem in said bore, a seat carried by said stem, and means for adjusting the height of the seat, said adjusting means including a vertical row of notches in the side of the stem forming ratchet teeth, each notch having a horizontal upper shoulder and an inclined lower shoulder, a pawl mounted on said pedestal and horizontally slidable through the side thereof to enter any of said notches, said pawl having a horizontal upper edge extending substantially to the extremity of the pawl and a lower edge which is horizontal except for an inclined portion adjacent to said extremity, each said notch being of such size as to receive the extremity of said pawl with its upper edge bearing on the horizontal upper shoulder of the notch and the inclined portion of the lower edge of said extremity bearing on the inclined lower shoulder of the notch, said stem also having an aperture therethrough below said notches and with horizontal upper and lower shoulders engageable by horizontal portions of the upper and lower edges