BACKGROUND OF THE INVENTION
This invention relates generally to improved apparatus for moving objects from one surface area to another and more particularly to an apparatus for lifting and transferring invalids from a bed to a cart and vice-versa without requiring manual exertion.
1. Field of the Invention
In hospitals and nursing homes it is required that the patients be transferred from one surface of rest to another as from a bed to a wheeled cart, or from a wheeled cart to an operating table or an x-ray machine or the like. Many of the patients are invalids or paralyzed and thus cannot assist in the transfer. The patients at first were manually lifted and transferred. At times, determined mainly by the weight and condition of the patient, many persons were required to accomplish this task. It became obvious that easier means were needed to transfer a patient.
2. Prior Art
Some present-day patient transfer devices comprise a plurality of rollers supporting an endless belt forming a platform. Many devices have been designed to accomplish the transfer of a patient from a bed to a wheeled cart via the endless belts. However, each required excessive handling of the patient or were not suitable carts for transferring an ambulant patient without unnecessary precautions.
Some prior art devices included a pair of superposed endless belts. The leading edge of the upper belt is rotating in an upwardly-oriented direction to lift the patient up onto the upper belt of the transfer device. The lower belt, however, is rigidly located in the cart and drives the upper belt to and from the extended position.
SUMMARY OF THE INVENTION
The patient transferring device according to the present invention is a conveyor type device that, when attached to a well-known transfer cart presently used in hospitals, shifts the patient from bed to cart without excessive manual handling. The patient transferring devices includes two superposed endless belts or tracks, end-supported by a slider mechanism. Journaled between the slider mechanism of both endless belts are a plurality of rollers supporting the endless belts. Separately actuatable drive means rotate the endless belts in opposite directions.
The lower endless belt drives both belts to the patient. The upper endless belt rotates in the opposite direction to gently grasp the patient and transfer the patient to the upper endless belt. The slider mechanism extends and supports both belts. After the patient is transferred to the center of the upper endless belt, the drive to the upper endless belt is disengaged and the drive is reversed to cause the lower endless belt to drive both belts to the home position.
In order to adapt the patient transferring device to the contour of the bed, the upper and lower endless belts are separated into two sections and universal joining means are employed to permit the raising of one section of the patient transferring device.
At least one end roller of both sides of the upper endless belt is fastened to a separate frame pivotably fastened to an end frame comprising a portion of the slider mechanism. This is to permit raising and lowering a portion of each end of the upper endless belt platform. Means are provided to support the pivotably mounted separate frame in the raised position.
The plurality of rollers of both endless belts are spaced such that the center of the belt is void of drive rollers. This permits the taking of x-ray films of the patient while the patient transferring device is in its extended position.
It is, therefore, an object of the present invention to provide enhanced apparatus for transferring patients.
It is another object of the present invention to provide an improved means for transferring a patient to or from a wheeled cart without manual handling of the patient.
It is another object to provide an improved driven endless belt conveyor means for transferring patients.
Still another object is to provide an improved endless belt conveyor means for transferring patients which includes means to conform the conveyor means to the bed.
Yet another object is to provide an improved endless belt patient transferring means which includes means for raising and supporting the ends of the transferring means to prevent the patient from rolling from the transferring means.
Another object is to provide a patient transferring means that permits leaving the patient on the transferring means during the taking of x-ray films.
These and other objects of the present invention will become apparent to those skilled in the art as the description proceeds.
BRIEF DESCRIPTION OF THE DRAWING
The various novel features of this invention, along with the foregoing and other objects, as well as the invention itself both as to its organization and method of operating, may be more fully understood from the following description of an illustrated embodiment when read in conjunction with the accompanying drawing, wherein:
FIG. 1 is a perspective view of one embodiment of the patient transferring device adapted to a roll-about cart;
FIG. 2 is a sectional view taken along the lines 2--2 of FIG. 1 and shows the drive mechanism;
FIG. 3 is a detailed view of the drive gears of FIG. 1 with the gear cover removed showing the gear arrangement for driving the drive mechanism of FIG. 2;
FIG. 4 is another view of the drive gears of FIG. 3 with one driven gear removed from engaging the driving gear;
FIG. 5 is a detailed view of the folding member support as shown in FIG. 1;
FIG. 6 is a detailed view of a universal joint mechanism usable in the device according to the present invention as shown in FIG. 1;
FIG. 7 is a detailed view of a clamping mechanism for fastening the device according to the present invention to the table of a cart;
FIG. 8 is an end view of a cart containing the device according to FIG. 1, positioned next to a bed with the device extended over the bed;
FIG. 9 is a detailed perspective view of the slider mechanism according to the device shown in FIG. 1;
FIG. 10 is a sectional side view taken along lines 10--10 of FIG. 9; and
FIG. 11 is a perspective view of a second embodiment of the present invention adapted for use as a stretcher.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a typical embodiment of a transporter device 10 in accordance with the present invention is illustrated. This form of transporter device is especially useful for transferring and carrying patients or nonambulatory individuals from place to place. The illustrated device includes a patient transferring device 12 mounted on a transfer cart 14. The transfer cart 14 includes a platform 16 (see FIG. 7) mounted on wheels or casters 18 so that it may be easily rolled and moved from one location to another. The transfer cart 14 includes a vertical lifting section (not shown). The lifting section provides vertical or height adjustments for the patient transferring device and permits an adjustment of the patient transferring device to match the height of an adjoining surface to or from which a patient is to be moved. The transfer cart 14 does not form a portion of the present invention and is described here only briefly merely to set the stage for a later description of the operation of the present invention.
The patient transferring device 12 according to FIGS. 1 and 2 comprises two tracks or conveyors, an upper track 20 and a lower track 22, preferably covered by an endless belt of heavy material such as canvas or rubberized fabric. The tracks encircle a plurality of rollers 24 extending the length of the patient transferring device. The rollers 24 therefore should be of a length sufficient to fully support a patient over his entire length. The upper track 20 encompasses a plurality of the rollers 24, ten in number shown in FIG. 1. Five rollers are located to the right and five to the left of a driving gear 26. An endless chain 28 interconnects the driving gear 26 with a gear 30 fastened to an end of each of the plurality of rollers 24 in the upper track. The lower track 22 includes a plurality of rollers 24, four in number shown in FIG. 2, encircled by a second endless belt. Again this endless belt can be made from a heavy material such as canvas or rubberized fabric.
The lower track 22 drive comprises a driving gear 31 driving a second endless chain 29. The endless chain drives the rollers 24 and the endless belt of the lower track 22 via gears for the upper track 20. The driving gear 31 is journaled to a shaft 33 which in turn is fastened to an end frame 36 of a sliding mechanism 34 shown in FIG. 5. The number of rollers 24 shown supporting the upper and lower track should not be taken as limiting the present invention. More or less rollers could be used. The rollers must drive the tracks and support the patient.
Referring again to FIG. 1, the patient transferring device 12 includes a gearbox 32 for driving the endless chain 28 and 29 and rollers 24 as shown in FIG. 2. The arrangement of the gears for driving both the upper and lower track is shown in FIG. 3, while the gear configuration for driving the bottom track only is shown in FIG. 4. The rollers 24 are journaled to the end frame 36 of the sliding mechanism 34 shown only generally in FIG. 1. The interconnections of the slider mechanism 34 is shown in FIGS. 9 and 10. The interconnection of the rollers 24 with the end frame 36 of the slider mechanism 34 is shown in FIG. 7.
The patient transferring device 12 is shown in FIG. 1 clamped to the transfer cart 14. The details of the clamping device are shown in FIGS. 7, 9 and 10. Referring now to FIG. 7, the clamping device is adjustable to various lengths and thicknesses of platforms 16 of different transfer carts. The clamping device includes a bracket 38 fastened to the slider mechanism and an L-shaped channel bracket 40. The L-shaped channel bracket 40 is fastened to the bottom side of the platform 16 by screws 41 for instance. Bracket 38 fits within the channel of the L-shaped channel bracket, see FIG. 9. A plurality of wing nuts 42 hold the bracket 32 firmly within the channel. The enclosure gear/chain mechanism and slider details are not shown in FIG. 7 for clarity in showing the fastening of the patient transferring device to the cart. A similar clamping device comprising brackets 38 and 40 and wing nuts 42 hold the patient transferring device to the transfer cart at the opposite end to that shown in FIG. 1.
Referring again to FIGS. 1 and 2, a folding member support feature 43 of the present embodiment is shown. The end rollers on both sides of the patient transferring device can be pivoted to raise both ends of the upper track to form a barrier. A portion 44 of the end frame 36 to which the rollers 24 are journaled is pivoted at a pivot point 46 to raise and lower the end rollers. The placement of the rollers are shown in FIG. 2 in solid lines in its lower or patient transferring position and in dotted lines on the left side raised to its upper or barrier position. The lower position is used while transferring a patient to or from the patient transferring device and the upper position is used while the patient is being transported in the transfer cart. The upper position will prevent a patient from accidentally rolling off the transfer cart. This is especially important if the patient is agitated and moving about uncontrollably. The sides of the patient transferring device are held in an upright position by a spring-loaded bent rod 48 shown in FIG. 5. A similar spring-loaded bent rod 48 is located at all four corners of the patient transferring device in order to hold the end rollers of the upper track on both sides in the barrier position.
In FIG. 5, the details of one of the folding member supports are shown. The spring-loaded bent rod 48 is pulled from its home position 50, dropped to a semi-vertical position, and engages any one of the small slots 52 to fold the edge of the upper track in an upper direction to a desired angle. FIG. 5 shows the rod 48 positioned in the barrier position to prevent a patient from falling from the cart.
Referring again to FIG. 1, the patient transferring device according to the preferred embodiment is divided into two sections 54 and 56. The first section 54 shown raised in FIG. 1 is used preferably for the upper portion of the patient to be transferred. The first section 54 can be raised or lowered to a flat position, depending upon the position of the bed that the patient is to be transferred to or from. The section 56 of the patient transferring device 12 remains in a horizontal position. The sections can be activated independently through the use of universal coupling means at the separation point dividing the first section from the second section. Each of the rollers 24 in both the upper and lower tracks are fastened together by a universal joint 58. This permits the raising of the first section 54 while providing a common drive for the entire track. A detail of one of the universal joints 58 usable in the present embodiment is shown in FIG. 6. The universal joint 58 of FIG. 6 includes a ball-bearing race 60 which permits smoother rotation of the rollers. The first section 54 can be held in a raised position by any number of means including a spring-loaded bent rod as detailed in FIG. 5 for the folding member support, or the transfer cart 14 can be built to provide a platform hinged at the separation, with the platform supporting the first section of the patient transferring device in both the raised and lowered positions. The details of the support to hold the first section in the raised position are believed to be obvious and are not shown here.
Referring again to FIG. 1, the plurality of rollers 24 included in the upper track 20 and lower track 22 of the patient transferring device 12 are journaled to the end frame 36 of the slider mechanism 34 and rotated by the driving system shown generally in FIG. 1. The driving system includes a fold-away crank 62 and an enclosed gear and chain system (shown in FIGS. 2, 3 and 4). The details of the slider mechanism 34 are shown in FIGS. 9 and 10. Referring to FIG. 9, the slider mechanism 34 includes the end frame 36 to which the rollers 24 are journaled and a plurality of sliders 64 having support slider wheels 66 snugly fitted into each channel member 70 of the sliders 64. Two sliders are shown in FIGS. 9 and 10, but it is obvious that perhaps one or many more than two could be used. The two sliders 64 shown should not be taken as limiting the number of sliders in the present application.
As the patient transferring device is actuated by turning the crank handle, the upper track and lower track move to an extended position from the transfer cart to which the patient transferring device is clamped as previously described. In the extended position the upper and lower tracks are supported by the bed or other table form to which the patient is being transferred, and the slider mechanism. The slider wheels 66 are journaled to shafts 68 fastened to the sliders 64 and roll within channels 70 of the slider mechanism. The slider wheels 66 are held into place within the channel 70. A slot 72 is formed in the channel 70 to permit the movement of the wheel 66 within the channel. The two sliders are fastened together to provide a longer extension of the tracks of the patient transferring device. A portion of the crank and gear enclosure 36 serves as part of the inner slider. This portion includes a slot 74 to receive only one wheel of the inner slider since at this point of operation, extended over a bed or table, the weight of the patient transferring device and the patient is supported by the bed or the table.
The turning of the upper track 20 and lower track 22 via the rollers 24 is accomplished by the gear and endless chain mechanism driven by the fold-away crank 62. Although a hand crank is shown in the figures presently being described, it is obvious that any other type of driving mechanism can be used such as an electrical motor. The electrical motor requirements would be that it must be reversible and be geared down to provide a low number of revolutions per minute combined with sufficient power to drive all of the rollers and the tracks with a patient being conveyed by the tracks.
The gears driving the mechanism of the patient transferring device are shown in FIGS. 3 and 4 without the gearbox cover 32 shown in FIG. 1. The gear drive mechanism comprises a large driving gear 76 journaled in the gearbox and fastened to the driving handle 62. Two intermediate pinion gears 78 and 80 are shown, along with a first driven gear 82 driven by the second intermediate pinion gear 80. The first driven gear 82 is fastened to the shaft 33 journaled to the end frame 36 of the slider mechanism 34. The shaft 33 drives the gear 31 shown in FIG. 2, and thereby drives the rollers of the lower track and the track itself via the endless chain 29 and gears 30. A second driven gear 86 of the gear mechanism shown in FIGS. 3 and 4 is shown fastened to a handle 88 which controls the meshing of the second driven gear 86 with the first pinion gear 78. As shown in FIG. 4, the second driven gear 86 is fastened to the handle 88 and to a square rod 90. The square rod 90 couples with the driving gear 26 of the upper track 20 as shown in FIG. 2. Thus, if the second driven gear 86 of the gearbox is meshed with the first pinion gear 78 as shown in FIG. 3, the upper track 20 is driven in one direction while the lower track 22 is driven in the opposite direction. If the second driven gear 86 is removed out of engagement with the first pinion gear 78 by pulling the handle 88, only the lower track 22 is rotated when the driving handle 62 is turned.
Referring now to FIG. 8, in employing the patient transferring device 12 for its intended purpose, as for the transfer of a patient from a bed 92 to the cart 14 having the patient transferring device clamped thereto, the cart 14 is rolled to a position alongside the patient's bed 92. The height of the cart is adjusted so that the top of the cart is level with the top of the bed. The first section 54 of the upper track (see FIG. 1) is adjusted to conform to the position of the bed, that is, if the upper torso of the patient is elevated by the bed, the first section of the upper track is elevated to match. An operator then rotates drive handle 62, or activates the electric motor if an electric drive is used, to advance the patient transferring device toward the bed. Thus looking at the patient transferring device as shown in FIG. 8 and the gear mechanism as shown in FIG. 3 with the upper track drive gear engaged, the drive handle 62 would be rotated in the direction of the arrow shown in FIG. 3. The rotation of the lower track in a counterclockwise direction would cause the patient transferring device to transfer from the cart to the bed. The upper track in the meantime is rotating in the oposite or clockwise direction as viewed from the direction of FIG. 8. As the drive handle 62 is continually rotated, the upper and lower tracks are moved in the direction of the patient. When the upper track 20 contacts the patient, the upper track will lift the patient because the leading edge of the upper track is rotating in an upward direction. The upper track is continually rotated by the driving handle and the patient will be gently lifted onto the upper track while at the same time the lower track is causing the upper track to be moved in the direction toward the patient.
At this time the slider mechanism 34 of FIGS. 9 and 10 is being extended away from the cart. The slider mechanism permits the upper and lower track to be easily conveyed from the table top of the cart out across the patient's bed. The clamping means shown in FIGS. 1, 9 and 10 in the meantime holds the channel of one slider, and thus the patient transferring device, firmly to the table top of the cart.
Once the patient is located in the middle of the upper track, the handle 88 fastened to the second driven gear 86, see FIGS. 3 and 4, is pulled to remove the second driven gear 86 from mesh with the first pinion gear 78. Thus the upper track drive is disengaged and only the lower track remains engaged with the driving means, the drive handle 62 of FIGS. 3 and 4. Drive handle 62 is then rotated in the opposite direction, opposite to the arrows shown in FIGS. 3 and 4. Rotating the large driving gear in the counterclockwise direction causes the first driven gear 76 to rotate in a clockwise direction, thereby causing the rollers 24 of the lower track 22 to rotate in a clockwise direction via the endless chain 29, see FIG. 2. Rotating the lower track 22 in a clockwise direction causes the upper and lower track to return to the table top of the cart, all while keeping the patient in the center of the upper track since the upper track is no longer moving. Once the upper track containing the patient is located back over the center of the cart, the rotation of the driving gear is halted. The folding member support 43 can then be engaged by lifting the ends of the rollers and allowing the spring-loaded bent rod 48 to be placed in one of the slots 52 as shown in FIG. 5. The patient is now ready to be transported to another bed or to an x-ray table, for instance.
Another feature of the patient transferring device is that no rollers are located in the center of the device to interfere with the x-ray film. Therefore, after the patient is transferred from the bed to the cart via the patient transferring device according to the present invention, a patient can be transported to the x-ray room. In the x-ray room the cart is placed directly alongside the x-ray table, and the patient transferring device is activated as previously stated. Except in this instance since the patient is already located on the device, the upper track 20 is left inactivated by leaving the second driven gear 86 out of engagement with the first pinion gear 78. Thus as the handle or driving means causes the large driving gear 76 to rotate in a clockwise direction, the lower track 22 is rotated in a counterclockwise direction causing the patient to be conveyed from the cart to the x-ray table on the upper track 20. The drive handle 62 is turned until the patient is positioned under the x-ray machine. In this position, the x-ray technician can take an x-ray picture of the patient without removing the patient from the patient transferring device of the present invention since there are no rollers 24 in the center of the tracks beneath the patient to interfere with the x-ray film (see cutaway section of FIG. 1). The handling of the patient is decreased and therefore less harm can come to the patient. After the x-rays have been taken, the drive mechanism is actuated in the reverse direction, again leaving the upper driving mechanism disengaged. The patient is transferred from the x-ray table back to the cart for transfer directly back to his bed without requiring a multiplicity of handling of the patient and without requiring that the patient be removed from the cart because of possible x-ray interference by the patient transferring device.
Referring now to FIG. 11, another embodiment of the patient transferring device 12 is shown in a stretcher concept. Handles 94 have been added to the slider mechanism 36 of the patient transferring device to permit the carrying of the patient on the patient transferring device by two attendants, one at each end holding the handles. The stretcher concept also includes caster wheels 96 for rolling the stretcher around if possible. The caster wheels 96 are shown on a frame member that could be similar to the table top of the cart shown in FIG. 1. The folding member support feature 43 of the patient transferring device has an added advantage in the stretcher concept of the present embodiment. The frame member of the embodiment shown in FIG. 11 could include a quick disconnect so that the stretcher concept could be placed onto a cart and fastened to the cart for wheeling the patient to his room. The patient transferring device could then be activated to transfer the patient from the cart into the bed, again without excessive handling of the patient.
The principles of the present invention have now been made clear in an illustrated embodiment. There will be immediately obvious to those skilled in the art many modifications of structure, arrangement, proportions, the elements, materials and components used in the practice of the invention. For instance, the details of the rollers as shown in FIGS. 6 and 7 show the rollers made of a cloth-like material over a rubber covered metal roller. Likewise the driving mechanism is shown as comprising a drive gear, two driven gears, and two intermediate pinion gears. It should be immediately obvious to those skilled in the art that many other materials could be used for the rollers such as the soft plastics readily available and that the drive mechanisms could be independent drives, without interconnection for instance. The appended claims are, therefore, intended to cover and embrace any such modifications, within the limits only of the true spirit and scope of the invention.