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EP-3908470-B1 - MANUAL PALLET JACK HITCH AND RELATED SYSTEMS AND METHODS

EP3908470B1EP 3908470 B1EP3908470 B1EP 3908470B1EP-3908470-B1

Inventors

  • JOHNSON, DAN

Dates

Publication Date
20260506
Application Date
20200109

Claims (12)

  1. A pallet jack hitching system comprising : (a) a hitch mechanism comprising a hitch body removably coupled to a power assist device via a tensioned piston assembly, wherein the hitch mechanism comprises: (i) a proximal hitch body (44) removably coupleable to a power assist device (30); (ii) a tensioned piston assembly (43, 46, 47, 48) comprising: (A) a stationary piston body fixedly coupled to the proximal hitch body (44); and (B) an extendable tensioned piston rod extending from the stationary piston body; and (iii) a distal hitch body fixedly coupled to the tensioned piston assembly (43, 46, 47, 48), the distal hitch body (32) comprising a mateable coupling structure (50, 52, 54) disposed on the distal hitch body; and (iv) an actuation assembly (84) operably coupled to the distal hitch body (32), wherein actuation of the actuation assembly can urge the distal hitch body between a raised position and a lowered position; characterized in that the pallet jack hitching system further comprises: (b) a manual pallet jack (60) mateable with the mateable coupling structure of the distal hitch body; and (c) a release actuation mechanism (130) disposed on the manual pallet jack, wherein the release actuation mechanism is disposed in proximity with a release button (136), wherein actuation of the release actuation mechanism causes actuation of the release button.
  2. The hitching system of claim 1, wherein the mateable coupling structure comprises a notch (54).
  3. The hitching system of claim 1, wherein the extendable tensioned piston rod (48) is moveable between a retracted position and an extended position.
  4. The hitching system of claim 3, wherein the retracted position is an untensioned position and the extended position is a tensioned position.
  5. The hitching system of claim 3, wherein the movement of the tensioned piston rod (48) into the extended position causes the distal hitch body (32) to move into the lowered position.
  6. The hitching system of claim 3, wherein the movement of the tensioned piston rod into the retracted position causes the distal hitch body to move into the raised position.
  7. The hitching system of claim 1, wherein the power assist device comprises: (a) a power assist device body (34); (b) at least two wheels (38A, 38B) operably coupled to the power assist device body; (c) an actuator operably coupled to at least one of the at least two wheels; (d) a steering mechanism (36) coupled to the at least one of the at least two wheels (38A, 38B); (e) a power assist device coupling structure (42) operably coupled to the power assist device body; wherein the distal hitch body (32) is removably coupleable to the manual pallet jack (60) at the mateable coupling structure and wherein the coupling mechanism of the hitch mechanism (44) is removably coupleable with the power assist device coupling structure (42).
  8. The hitching system of claim 1, wherein the release actuation mechanism is a hydraulic release actuation mechanism (130) and the release button (136) is a hydraulic release button.
  9. The hitching system of claim 1, wherein the power assist device (30, 88) is an autonomous power assist device.
  10. The hitching system of claim 1, further comprising a remote control in communication with the actuation assembly (84), wherein the remote control comprises a first actuation mechanism (130) for actuating the actuation assembly to urge the distal hitch body (32) into the lowered position.
  11. The hitching system of claim 10, wherein the remote control is in communication with the hydraulic release actuation mechanism (130), wherein the remote control comprises a second actuation mechanism for actuating the hydraulic release actuation mechanism to actuate the hydraulic release button.
  12. The hitching system of claim 1, further comprising an angled coupling feature defined at or near a distal end of the distal hitch body (32).

Description

Cross-Reference to Related Application(s) This application claims the benefit under 35 U.S.C. § 119(e) to U.S. Provisional Application 62/790,225, filed January 9, 2019 and entitled "Manual Pallet Jack Hitch and Related Systems and Methods". Field The various embodiments herein relate to warehouse transport and hauling equipment, and more specifically to pallet jacks and power-assist devices for coupling to and providing motive power for transporting such jacks around a warehouse or similar environment. More specifically, various implementations relate to interchangeable hitching mechanisms for use in combination with the power-assist devices to couple such devices to the various known manual pallet jacks. Background There are multiple manual pallet jacks on the market. One example of such a manual jack is shown in FIGS. 1A and 1B, which depict standard pallet jack 10. The jack 10 has a body 12, two pallet forks 14A, 14B extending from the body 12, two fork wheels 16A, 16B at the distal ends of the forks 14A, 14B, a steering mechanism 18, and two swivel wheels 20A, 20B operably coupled to the steering mechanism 18. As best shown in FIG. 1B, the two swivel wheels 20A, 20B are coupled to the elongate member 22 of the steering mechanism 18 via a fixed axle 24, which is fixedly coupled to the elongate member 22. Each of the swivel wheels 20A, 20B rotate around the fixed axle 24. When the steering mechanism 18 is urged to the right or left by a user, this causes the fixed axle 24 to rotate around an axis parallel to the steering mechanism 18, thereby causing the wheels 20A, 20B to swivel. This action allows the user to steer the pallet jack 10. In some rare circumstances, manual pallet jacks such as the one described above are modified to add a motor that can be used to propel the jack, thereby reducing the amount of effort required by the user. However, such modifications are unusual and there are very few commercial options available for such a retro-fitting, probably because the known commercial options are not optimal. One of the few known options is a product called the Power Pallet™, which is available from PowerHandling Inc. of Spokane, WA. One of the disadvantages of this product is that it doesn't fit all manual pallet jacks. Another disadvantage is that the product is mounted on the front of the handle and swivel wheels of the pallet jack and extends from the front, thereby increasing the size and footprint thereof. This increase to the overall size and footprint of the pallet jack handle causes interference between the Power Pallet product on the handle and the jack itself when a user attempts to turn, thereby making it difficult to steer the jack. US6244813 discloses a motorcycle towing device including a platform member with a front end for attachment to the trailer hitch of a land vehicle. US5366338 discloses a tow bar designed for lifting the front wheel and towing a two-wheeled automotive vehicle on its rear wheel and is removable for storage. US2006027998 discloses a trailer hitch attachment that has an elevation adjuster to move elongated members that extend horizontally toward a rear of the attachment between a supporting surface and a trailer hitch of a motor vehicle. US2006273547 teaches a hitch assembly for coupling a powered cart. GB2279934 teaches a device for transporting a load including: a base, a drive means mounted on the base; a steerable wheel mounted for rotation on the first end portion of the base, the steerable wheel being drivable by the drive means; a pair of wheels mounted for rotation on a second end portion of the base; a lifting means, mounted generally at the first end portion of the base, comprising a coupling which is movable in a generally vertical plane and is adapted to engage and bear the load, the device being constructed such that in use when the coupling is bearing the load, the pair of wheels are lifted from the ground. There is a need in the art for an improved device, system, and method for propelling a manual pallet jack. Brief Summary The present invention is defined in the appended claims. Discussed herein are various power-assist devices with interchangeable hitch mechanisms that can couple to many known manual pallet jacks. In Example 1, an interchangeable hitch mechanism comprises a distal hitch body, an angled coupling feature defined at or near the distal end of the distal hitch body, a mateable coupling structure disposed on the distal hitch body, a proximal hitch body, a tensioned piston assembly, and a pusher device coupling mechanism disposed at a proximal end of the proximal hitch body. The tensioned piston assembly comprises a stationary piston body fixedly coupled to the proximal hitch body, and an extendable tensioned piston rod extending from the stationary piston body, the extendable tensioned piston rod fixedly coupled to the distal hitch body. Example 2 relates to the interchangeable hitch mechanism according to Example 1, wherein the mate