US 3380085 A
Description (OCR text may contain errors)
April 30, 1968 R. H. FERNEAU ETAL 3,380,085
MULTI-PURPOSE STRETCHER CHAIR Filed Oct. 24, 1966 2 ASheets-Sheet l INVE NTOR //CHA/elo H FERNE/1u CSE G50/265 A. SEL/6,
BY 55am l1/Z2,
ATTQRN evs 3,380,085 MULTI-PURPOSE STRETCHER CHAIR Richard H. Ferneau and George A. Selig, Washington Court House, Ohio, assignors to Ferm-Washington Inc., Greenfield, Ohio, a corporation of Ohio Filed Oct. 24, 1966, Ser. No. 589,044
8 Claims. (Cl. 5-86) ABSTRACT F THE DISCLOSURE A multi-purpose stretcher chair construction wherein an elongated body supporting frame isadapted to be raised and lowered relative to an undercarriage mounted on wheels, the body supporting frame being connected to the undercarriage by means of coacting pairs of crossforming frame members which are pivotally connected at their upper ends to the body supporting frame and pivotally and slidably connected to the undercarrage, the cross-forming frame v*members being movable relative to each other by means of an elevating mechanism compris- This invention further constitutes an improvement over U.S. Patent No. 2,958,873, for Multiple Position Elevating Cot, issued Nov. 8, 1960, to one co-inventor of the present invention.
Heretofore, one major problem in transferring patients, particularly elderly ones, was the need to place the patient closely adjacent to the receiving cot, bed, or operating table with a minimum of effort by the attendants and strain on the patient. To this end the conventional stretcher-like ambulance cot gave way to the dual position cot, i.e., one having an up and down position achieved by the addition of collapsible legs, then to the variable incremental height cot taught by the aforementioned patent. This was a maior advancement as a tot constructed in accordance with the teachings therein enabled the attendants to preselect a height dictated by the circumstances encountered. o
However, the latter was not the final answeradditional improvements were needed to further reduce the discomfortresulting from the necessary transfer of patients.
It is therefore, a'principal object of this invention to provide a multi-purpose elevating cot which may be readily adjusted to a potentially infinite number of positions between the lower and extended up positions.
A further object of the instant invention is the provision of a multi-purpose stretcher chair in which the body frame is elevated by a system so constructed that a braking mechanism therein prevents the weight of the patient acting to lower the body frame, but readily permits easy adjustment by an attendant.
A further object of the invention is the provision of a multi-purpose stretcher chair having a body support frame which can be changed quickly and easily from the flat horizontal position to a sitting position.
Still another object ofthe invention is the provision of a multi-purpose stretcher chair having an undercarriage with a fixed wheel base and supporting crossed'frame members, whereby the lateral extent of said frame members are confined within the area formed by the extremities of United States Patent C ice' said under carriage, thus assuring greater stability to the device.
Yet a further object of this invention is the provision of a multi-purpose stretcher chair in which tige body support frame is supported by a pair of cross members, said f cross members being connected by a plurality of brace members having cam followersmounted thereon to ride in a cam track in the elevating mechanism, the parts being so arranged that the actuation of the elevating mechanism will. cause the cams to move smoothly in the cam track resulting in the smooth relative movement of the body support frame.
Further objects and advantages will become apparent hereinafter to those skilled in the art upon reading the specification, especially in conjunction with the drawings wherein:
FIGURE 1 is a perspective view of the stretcher chair in an extended up position.
FIGURE 2 is a perspective view of the stretcher chair with parts removed in a sitting" position.
FIGURE 3 is an enlarged perspective view of the elevating mechanism.
FIGURE 4 is a sectional view of a portion of the elevating mechanism taken along line 4--4 in FIGURE 3.
FIGURE 5 is a sectional view of another portion of the elevating mechanism taken along line 5-5 in FIG- URE 3.
Turning now to the invention as illustrated in FIGURE l, it is to be. observed that the stretcher chair 1 made in accordance with the teachings hereinafter is a combination of essentially four major portions, indicated generally as body support frame 2, undercarriage 3, intermediate movable frame 4, and elevating mechanism 5.
The body support frame 2 is of generally rectangular shape in the extended position whereby support is provided for a patients body in the prone position. FIGURE 2 illustrates one of several alternative positions for the body support frame. To facilitate such changes, the body support frame 2 is comprised of at least three segments, preferablyfour. The middle portion 10 is fixed, while the end portions 1l, 12 and 13 are pivotally mounted thereto at 14, 15 and 16, respectively. When it is desirable to support a patient in a sitting position, end portion 11 is rotated about pivots 14 and held in the desired position by the braces 17. One end of each brace 17 is hinged at 18 to the side member 11a or 11b of end portion 1l. The opposite end of each brace 17 is provided with a series of teeth 19 arranged to selectively engage frame member 20 projecting below and transverse the middle portion 10. Frame member 20 may be attached to the middle frame portion by projections 2l.
Since it also may be desirable to collapse the opposite end of the support frame 2 to permit reclining of the patients legs, appropriate locks and attending releases may be provided at the pivot points 15 to accomplish such adjustment.
It should `be apparent that the stretcher chair will be provided with a suitable mattress (not shown) intermediate the body support frame 2 and the patient. Therefore, cross members 22 are selectively placed between opposing side rails 10a-10b, 11a-11b, andv12a-l2b, or in the alternative, perpendicular thereto. While the frame and support members may be formed of aluminum tubing, stainless or chrome plated steel tubing, it should be understood that the construction of the frame as such does not constitute a limitation of this invention and any standard frame may be employed, inclusive of frames having appurtenance's such as the arm support rails 23, and others such as stirrups and head elevating frame.
Projecting downward from the four corners of the middle portion 10 are fittings 24a, 2411, 24v and 24d, pairs of said opposed fittings mounting horizontally disposed rods Z5 and 26, which extend parallel to one another below the plane of the middle portion 10. The fittings 24a and 24d are mounted on extensions 10c and 10d of the side rails a-'10b, the extensions being telescopically received within the said side rail and extensible relative thereto. Sleeve-like fittings 27 and 28 surround rods 25 and 26 respectively, the fittings including sockets 29 and 30 which receive support members of intermediate movable frame 4, -another major portion of the structure which will now be described.
The intermediate movable frame 4 is the means by which support is given to the frame 2, and relative movement between frame 2 and undercarriage 3 is accomplished. Intermediate frame member 4 comprises a pair of cross-forming frame members 40 and 41, the upper ends of which are received in sockets 29 and 30. The lower ends are similarly mounted in a manner to be described hereinafter. Coacting cross-forming frame members 40a and 41a are pivotally connected to the cross-forming frame members 40 and 41 intermediate their ends at the pivot point 40b and 41h, respectively, said coacting members forming scissonlike elevating supports for the body support frame. Braces 42 are provided for-connecting the corresponding -legs of the cross members 40, 41 and 40a, 41a. These braces are spaced between the pivot points 40h, 41b, and the outermost ends of the legs, and may be mounted in the plane formed by the corresponding legs or juxtaposed to their upper and lower surfaces in the manner illustrated, Cam followers 43 are rotatively mounted on the braces 42 centrally thereof; and it will be shown later how said cam followers are adapted to ride in cam tracks which form an integral part of the elevating mechanism 5. By actuation of said mechanism, the opposing pairs of braces 42 will be caused to move relative to one another, thereby elevatingor lowering the body support frame 2. y
One important feature incorporated into the undercarriage 3 of the instant structure is that it is provided with a fixed wheel base. The undercarriage 3 comprises a generally rectangular frame composed of side frame members 50 and 51 connected together at their ends by the end frame members 52 and 53. Suitable comer joints 54, 55, 56 and S7 are used to effect this connection, plus also serving to mount caster wheels 58. These corner joints may be further provided with vertical projections 60 which afford additional support to the body support frame 2 when in the fully down position-contact being made with the under surfaces of the fittings 24a-24d.
A transverse member 65 extends parallel to the end member 52 and is secured to side frame niembers 50 and 5l. Toward the opposite end of the under'carriage, a second transverse member 66 is provided. The last named member is secured at its opposite endsto sleeve-like members or collars 67 and 68 which slidably vengage side frame members 50 and 51, respectively. Mounted for rotational movement on transverse members 65 and 66 are four T-shaped sleeve-like members 69, 70, 7l and 72 which receive ythe four lower ends of cross forming members 40, 40a, 41 and 41a. Therefore, it should be apparent that as the elevation of the body support frame is changed, sleeves 67 and 68 are caused to traverse at least a portion of the contained side frame members 50 and `51. Such movement corresponds to the telescoping movement of the side rail extensions 10c and 10d which permit movement of the upper ends of cross-forming frame members 40 and 51. Hence, throughout these changes the wheel base is constant.
Turning now to the elevating mechanism 5, illustrated in detail in FIGURES 3-5, it will be observed that the mechanism comprises two housings` 70 and 71, joined together by a threaded shaft 72 While it is not intended to be a limitation on this invention, said housings may 4 be east aluminum or other suitable material, or may be fabricated by known metal working operations. Though in appearance they may seem identical, each will be described separately for their distinguishing features. Housing 70, adapted to move axially along shaft 72 upon rotation thereof, is composed of three portions: a central portion 73 having a bore 74 therethrough, and identical goose-neck cam tracks 75 and 76 extending above and below the central portion. Received in said -bore is a ball bearing nut 77, containing a plurality of recirculating ball bearings 78 which ride in the circular grooves of shaft 72. The shaft and ball bearing combination is known perse, being manufactured by Saginaw Steering Gear Division, General Motors Corporation. By rotating shaft 72, housing 70, secured to the ball bearing nut by set screws 79, is caused to move axially of the shaft with a,minimum of friction thereagainst. The cam tracks are angled substantially 45 to the horizontal and receive the cam followers or rollers. For convenience and added insurance against misalignment of parts, the track surface 80 may be beveled to fit into the corresponding concave edge of roller 43.
Housing 7l mounts the goose-neck cam tracks 81 and 82, which are substantially identical to cam tracks 7\5 and 76. Attached to the end of shaft 72 and received in the bore 83 is a bevel gear 84, angled to receive `a companion bevel gear 85 and to be driven thereby. By this arrange ment of parts, elevation of the stretcher chair may be conveniently effected from the side. With the adoption of the substantially friction free ball bearing nut, the problem of back-lash was amplified, That is, the weight of the patients body, without a lock, resulted in the premature lowering of the body support frame. In place of the conventional ratchet arm for securing -the support frame,
such as illustrated in the aforementioned patent, it wasl discovered that by utilizing a brake such as shown in FIGURE 5, all back-lash was virtually eliminated with the result that an infinite number of sustained elevated positions were possi-ble.
The brake assembly employed herein comprises a first washer to receive a reduced unthreaded extension of shaft 72, slip washer 91 adjacent thereto, an inner race 92 force fitted to shaft 72 and contiguous with washer 91 at one edge 93, and having an annular channel 94 on the opposite edge, and an outer race 9S. While outer race 95 surrounds shaft 72, it is spaced a slight .distance therefrom. The inner edge 96 contains an annular channel 97, coacting with channel 94 to form a continuous circular channel for the reception of ball bearings. A final element of the brake assembly is the flat coiled spring brake 98 surrounding the respective races 92 and 95. The lateral movements of spring brake 98 are restricted by the flanged edge 99 on outer race 95 and slip washer 91. Thus, it should be apparent from the arrangement of the parts as shown, the brake is rendered operative only when a force is exerted through the assembly to turn the shaft in a direction which will cause the spring to be tightened with respect to the races. The brake is oriented so that the spring will be tightened under the inuence of forces acting to lower the supporting frame members. Yet positive movement of the shaft, as when turned by its crank handle, will readily overcome the holding force of the brake and the frame can be lowered by an attendant. The brake assembly is secured to the housing 7l by set screw 100 in contact with washery90.
A further element noted particularly in FIGURE 5 is the handle assembly used to effect rotation of shaft 72. At the end of said shaft extending through the brake assembly is secured a bevel gear 84. Angled 90 from shaft 72 is handle 101 projecting through opening 102 in housing 7l. Mounted at the end of handle 101 is a second y bevel gear 85 which drives gear 84 to cause rotation thereof. 1f should be understood at this point that any desirable or convenient gear ratio may be utilized to achieve the desired results, although a 2 to l reduction has been found suitable. A further modification, still within the spirit of this invention, is the provision of a slip gear in the handle assembly whereby the handle 101 may be secured in a retracted position when not in use.
These and other modifications may be made in the structure without departing from the spirit and scope of this invention.
The embodiments of the invention in which an exclusive property or privilege s claimed are defined as follows:
1. In la stretcher chair construction wherein coacting cross-forming frame members are pivotally secured together intermediate their opposite ends and serve to raise and lower a body support frame relative to an undercarriage, the improvement which comprises elevating means for raising and lowering said cross-forming frame members relative to each other, said elevating means comprising a screw shaft, a pair of housings on said screw shaft, a first of said housings being axially movable along said screw shaft upon rotation thereof, the second of said housings being at one end of said screw shaft with said shaft journaled therein and fixed against axial movement relative thereto, a crank arm projecting laterally from said second housing at right angles to said screw shaft and gear means within said second housing connecting said crank anm to said screw shaft, brake means also mounted Within said second housing in engagement with said screw shaft, said brake means acting to automatically resist rotating movement of said screw shaft in one direction while permitting free movement thereof in the opposite direction, cam means of gooseneck configuration having inner and outer cam surfaces projecting from each of said housings, and cam following rollers mounted on cross members extending between said cross-forming frame members, said rollers riding between said inner and outer cam surfaces, said cam means and said rollers being arranged in opposing pairs and serving as the sole means for mounting said elevating mechanism relative to said frame members.
2. In a stretcher chair construction wherein coacting pairs of cross-forming frame members are pivotally securing together intermediate their opposite ends and act to raise and lower a body support frame relative to an undercarriage, the improvement which comprises elevating means for raising and lowering said cross-forming frame members relative to each other, said elevating means comprising a screw shaft, a pair of housings on said screw shaft, a first of said housings being axially movable along said screw shaft upon rotation thereof, the second of said housings being at one end of said screw shaft with said shaft journaled therein and fixed against axial movement relative thereto, a crank arm operatively connected to said screw shaft for rotation thereof, brake means in said second housing in engagement with said screw shaft, said brake means acting to automatically resist rotating movement of said screw shaft in one direction while permitting free movement thereof in the opposite direction, elongated cam tracks extending diagonally outwardly from said housings, said cam tracks being arranged in oppositely extending pairs, cross members extending between the corresponding upper and lower portions of said pairs of cross-forming frame members, there being two upper cross members and two lower cross members lying in spaced relation to the pivot points -of said crossforming frame members, cam rollers mounted on said cross members in engagement with said cam tracks, each pair of cam tracks contacting the rollers on corresponding upper and lower frame members, said cam tracks being positioned so that movement of said housings toward each other will act to expand said cross-forming frame members and movement away from each other will act to contract said cross-forming frame members, whereby to selectively raise and lower said body support frame relative to said undercarriage.
3. The structure claimed in claim 2 wherein said screw shaft has an extension at one end in engagement with said brake means, said brake means including a first race force fitted to said shaft extension, a second race adjacent said first race but mounted for rotational movement about said shaft extension, and a coiled compression spring contiguous with and substantially surrounding said first and second races.
4. The structure claimed in claim 2 wherein said first housing mounts a ball bearing nut containing a plurality of recirculating ball bearings engageable with said screw shaft.
5. The structure claimed in claim 2 wherein said cam tracks are of gooseneck configuration having inner and outer cam surfaces engageable with opposite peripheral portions of said cam rollers.
6. The structure claimed in claim 2 in combination with an elongated body support frame having three segments pivotally connected together in end-to-end relation, the upper ends of said cross-forming frame members being pivotally connected to said center segment, whereby said outlying segments are free to move relative to said crossforming frame members.
7. The structure claimed in claim 6 wherein said undercarriage is of fixed length, wherein the corresponding lowermost ends of one of the cross-forming frame members in each pair are pivotally connected to said undercarriage toward one end thereof, and wherein the remaining lowermost ends of said cross-forming frame members are slidably mounted on said undercarriage toward the opposite end thereof.
8. The structure claimed in claim 7 wherein vertical projections extend upwardly from the corners of said undercarriage in alignment with said body support frame, thereby lproviding support for said body support frame when in its lowermost position.
References Cited UNITED STATES PATENTS 2,958,873 1l/l960 Ferneau 5-63 X 3,147,039 9/ 1964 Smith et al 5-86 X 3,217,340 11/1965 Durr 5-63 3,308,485 3/ 1967 Evans 563 CASMIR A. NUNBERG, Primary Examiner.