This invention relates generally to methods, systems and apparatus for implementing lifts, hoists and the like in motor vehicles, especially for use in connection with personal-mobility devices such as scooters, wheelchairs, etc.
With the growing aging population, there are increasing numbers of mobility-impaired persons relying on mobility devices such as powered wheelchairs (PWCs) and power operated vehicles (POVs), or scooters, for an independent lifestyle. In order for those disabled persons to drive or ride as passengers in private motor vehicles, several means of transporting their mobility devices have been devised, such as trunk lifts, platform lifts and ramps. Crane-type hoists have been known and used for several years to accommodate loading and transporting mobility devices in hatchback-type vehicles such as minivans and SUVs.
The present invention will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which:
The following detailed description of the invention will refer to one or more embodiments of the invention, but is not limited to such embodiments. Rather, the detailed description is intended only to be illustrative. Those skilled in the art will readily appreciate that the detailed description given herein with respect to the Figures is provided for explanatory purposes as the invention extends beyond these limited embodiments.
As mobility devices have increased in size and weight, it has become essential to provide hoists that require less space in vehicle cargo compartments which, if anything, are becoming smaller as vehicles are downsizing. Additionally, as the variety of hatchback vehicle models has proliferated, so has the variety of mobility devices. In many motor vehicles, the bumper designs also have grown. In order to provide a more universal hoist to accommodate the increasing variety of vehicle and mobility device combinations, certain improvements in design have been made.
One of the most popular types of hoist for hatchback-type vehicles comprises a mounting base used to fasten the hoist to the vehicle floor. A mast assembly coupled to the mounting base provides a vertically elevated position for a lifting means, for example a boom to extend outside the vehicle and rotate the cargo (for example, mobility device) into the vehicle, a hoist drive system (for example, lift head assembly) for lifting the cargo, and an additional mast drive system to rotate the mast assembly (and any cargo carried by the lifting means) into the vehicle. For some vehicles, a third axis of horizontal linear motion is desired and/or required to extend the mast and mobility device beyond the vehicle (for example, beyond a vehicle bumper or the like). Embodiments of the present invention described and claimed herein are improvements over previous crane-type hoists.
As seen in the example of
The phrases “coupled to” and “connected to” and the like are used herein to describe a connection between two elements and/or components and are intended to mean coupled either directly together, or indirectly, for example via one or more intervening elements, where appropriate.
A mounting base according to one or more embodiments of the present invention is less confusing to assemble and install as compared to bases of earlier systems. It typically is desirable to mount the hoist as close to the rear hatch and adjoining interior wall (driver or passenger side) of the cargo area as practical. To accomplish this, a configurable base geometry is necessary. The mounting base provides a means of securing the hoist drive system and mast assembly to the vehicle floor using two leg extensions, generally at a right angle, to spread the loads resulting from lifting and rotating the mobility device. Instead of providing incremental adjustment of the base mounting legs via spaced holes, continuous adjustment is provided using telescoping tubes secured with set screws. This simplifies floor hole alignment during installation. The base provides, optionally, 3 or 4 fastening locations to secure the base to the vehicle floor. An additional offset leg position is provided for the forward-facing leg to clear the fender well on some applications. Also, the base assembly is symmetrical and can be turned upside down for mounting either on the passenger side (for example, the right side in the United States) or the driver side (for example, the left side in the United States) at the rear of the cargo area, adjacent to the hatch door. Additionally, flipping the base in this manner can provide a rear offset configuration.
Lifts according to embodiments of the present invention are modular in the sense that a multi-configurational positioning apparatus can include a base assembly described in detail below and/or a reversible head mount described in detail below to permit a wide variety of mounting configurations, positions and/or orientations using the a single set of components comprising the multi-configurational positioning apparatus, without the need for component customization or numerous different parts for achieving different orientations (for example, driver side versus passenger side configurations, right hand versus left hand head assembly orientations, rear offset spacing in a vehicle's storage space, side offset (from a wheel well or the like, for example) in the vehicle's storage space, etc.). This modularity means that a simple set of parts can be configured in many different ways to achieve a highly flexible and adaptable lift unit that can be installed, maintained and altered by a dealer or other individual responsible for the installation and implementation of vehicle lifts.
The base unit 200 (also referred to as a base assembly), shown in
Leg 204 and leg 206 are set at an angle that permits stable mounting of the lift 200. Typically a 90° angle can be used as the mounting angle, though the present invention is not limited to this configuration. An angle brace 212 can be used to help hold legs 204, 206 in a fixed mounting angle.
Leg 208 is mounted parallel to leg 204 in the embodiment of
In each
In some embodiments of the present invention, the mast drive system is comprised of an enclosed gearbox with an external, serviceable, motor that is fastened directly to the mounting base and supports the mast assembly. Limit switches can be pre-set to provide rotation end points constraining the mast rotation while moving the mobility device out from or in to the vehicle cargo area. Because the limit switches can be adjusted to restrict rotation between any two points over 360 degrees, the mast drive system can be configured in the field to a passenger side, driver side or other location.
As will be noted from the Figures, embodiments of the present invention use a direct drive system for rotating the mast assembly 400. That is, the motor 310 drives tube 320 directly; no chains or other flexible linkages are used. The sealed gearbox requires no adjustments (as a chain drive would), lubrication, or other scheduled maintenance for the life of the hoist. It also resists entry of contaminants such as water or grime. Being more compact than bulky chain drive systems, additional vehicle applications can be accommodated where cargo space is restricted.
As seen in
The mast assembly 400 is mounted on top of the mast drive means 300 and features an optional offset arm 420 to facilitate positioning a mobility device or other cargo alongside a vehicle for lifting (for example, on a sidewalk).
Optional horizontal offset arm 420 can be welded or affixed to post 410 by any other suitable means. Alternatively, arm 420 and post 410 can be components of a unitary mast 400.
As seen in the Figures, especially
The head assembly 500 (also referred to as a lift head assembly or boom assembly) is modular, can be provided with optional lifting features, and typically is pivotally mounted atop the mast assembly. A simple embodiment of the head assembly 500 includes a continuously-adjustable boom 520 with a winch-type hoist mechanism, as described in more detail below.
The boom angle can be pivotally adjusted by means of a turnbuckle 516, displaced opposite the lifting end of the boom to maximize the under-boom clearance when elevating the mobility device or other cargo. One end of the turnbuckle 516 is attached to the bracket 434 of mast offset arm mount 430 and the other end to the boom assembly 500. When the hoist 100 is not under load, the boom can be folded vertically by removing a hitch pin and pivoting it to a closed position, as shown in
In some embodiments of the present invention, the head assembly 500 uses two motors or equivalents thereto—a belt drive motor and a boom extension motor, as described in more detail below. Head assembly 500 is mounted to mast 400 using the head mounting bracket 430 (discussed above with regard to mast assembly 400) and is used to control raising and lowering of cargo. As seen in
As shown in the Figures, a chain drive speed reduction 514 can be used to transmit motion from the output shaft of belt drive motor unit 530 to control rotation of the spool 512 to play out and reel in belt 510. An appropriate latching, hook or lifting link 518 (also referred to herein as a cargo attachment point) can be attached to the end of belt 510 to engage the docking means on the mobility device or otherwise assist in lifting cargo (for example, a scooter, wheelchair or other personal mobility vehicle).
Further hoist movement is provided with an optional boom extension drive in the lift head assembly. This boom extension drive consists of a linear actuator unit extending and retracting the boom length when cargo needs to be placed farther outside the vehicle (for example, to clear the motor vehicle bumper or other external structure), or to accommodate motor vehicle hatch geometry. This boom extension drive system is located at a fixed position at the inboard end of the boom.
In some embodiments of the present invention, the cargo attachment point vertical position can be maintained at a constant height while the boom is being extended and retracted (that is, while the length of the boom is increased and decreased). A controller coordinates the boom extension drive and the belt drive, thus providing desired belt length compensation. By placing the bulky belt drive system in proximity to the mast in some embodiments, more vertical hoist travel is available to lift large mobility devices in a limited vertical space. Also, this position counterbalances the boom while being folded vertically.
Thus, some embodiments of the present invention include a system for extending and retracting the boom outer end terminus 502, as seen in the multi-positional diagram of
Using embodiments of the present invention, motor units 530, 540 can coordinate their operation so that sufficient, but not excessive, slack is available in the belt 510 at the outer end terminus 502 of boom 520. This typically involves maintaining the belt's cargo attachment point 518 at a constant height. A controller 550 can include a microprocessor or the like that coordinates operation of the motors in units 530 and 540. In one system, controller 550 uses a closed loop system that actually measures the rotation of the shafts of motors in units 530 and 540, takes into account any gear reductions or other adjustments, and then proportionally plays out or reels in the belt 510 using spool 512 so that a generally constant amount of slack of belt 510 is available outside of roller 528. In an open loop system, controller 550 can measure the EMF, current or other electrical signals used in connection with the belt and boom extension motors in 530 and 540. With these measured values, the controller 550 can use a lookup table or other reference to determine how much operation of the belt motor is needed to maintain a generally constant slack of belt outside of roller 528.
As noted above, the belt compensation system more particularly can use a combination of motors to assist a person in moving a scooter, wheelchair or similar device into and out of a vehicle. To keep the lifted device at a particular height while adjusting the boom length (that is, when extending or retracting the lift head's boom outer end terminus 502), the amount of belt extending through the boom can be adjusted automatically. In some embodiments of the present invention, the boom extension motor unit 540 is a linear actuator that includes encoding capability. One example of such a device is the LAS3-1 model linear actuator made by Hiwin Mikrosystem Corporation. This type of device can provide a signal to the controller 550 (for example, a microprocessor, microcontroller, etc.) that collects and adds/subtracts pulses sent from the motor unit 540 to determine the relative position of the linear actuator and thus the position/length of the boom 520.
Controller 550 then controls the belt motor unit 530, which can include encoding capability as well (for example, an encoder integral to or coupled to the belt motor itself). The belt motor unit 530 can include an optical shaft encoder coupled directly to the motor output shaft (which turns the belt winding spool 512). One example of an appropriate optical shaft encoder is the S5 model made by US Digital of Vancouver, Wash. The optical shaft encoder can also provide positional data to the controller 550 (for example, pulses indicating the position of the belt winding drum 512). The controller 550 can then reconcile positional differences as desired, again taking into account the amount of belt on spool 512, the thickness of the belt, etc. It may also be possible for an encoder or the like to actually measure the length of belt that has been extended by optically “viewing” belt movement itself.
Since the boom extension motor typically runs at a relatively slow speed, the controller 550 can adjust the speed of the belt motor by comparing pulse frequencies from encoders. The speed ratio is known and used to compensate for minor speed variations. The speed of the belt motor may be adjusted only during extension and retraction of the boom length. If the belt motor is run alone (or in other situations where coordination as that sometimes needed with the boom extension motor), then it can be run at full speed. When the belt compensation apparatus is used, the belt motor will feed out the belt when the boom extension motor is extending the boom 520. Conversely, the belt motor will roll up belt during boom retraction.
Thus the improved, modular lifting device shown in connection with embodiments of the present invention provides more universality for applications. A dealer, for example, can order a standard lift model and, using its multi-configurational positioning apparatus, configure the lift to a particular vehicle, mobility device and vehicle mounting position/location (for example, passenger or driver side) without requiring a custom mounting base or other custom components or equipment. A single model of lift also can be transferred from one motor vehicle to another motor vehicle more readily. “Warehouse models” can be provided to improve delivery time. Installation is simplified with the improved mounting base design and reversible head assembly mount. Field service is simpler with embodiments of the modular hoist of the present invention, facilitating substitution of standardized components for several models.
The many features and advantages of the present invention are apparent from the written description, and thus, the appended claims are intended to cover all such features and advantages of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, the present invention is not limited to the exact construction and operation as illustrated and described. Therefore, the described embodiments should be taken as illustrative and not restrictive, and the invention should not be limited to the details given herein but should be defined by the following claims and their full scope of equivalents, whether foreseeable or unforeseeable now or in the future.
Number | Date | Country | Kind |
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60844522 | Sep 2006 | US | national |
This application claims the benefit of priority under 35 U.S.C. §119(e) and any other United States or other law of the following: U.S. Ser. No. 60/844,522 (Atty. Docket No. 0201-p19p) filed Sep. 14, 2006, entitled VEHICLE LIFT, the entire disclosure of which is incorporated herein by reference in its entirety for all purposes.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US07/19850 | 9/13/2007 | WO | 00 | 3/12/2009 |