AU2014256368A1 - Lift chain tension relieving devices and methods - Google Patents

Lift chain tension relieving devices and methods Download PDF

Info

Publication number
AU2014256368A1
AU2014256368A1 AU2014256368A AU2014256368A AU2014256368A1 AU 2014256368 A1 AU2014256368 A1 AU 2014256368A1 AU 2014256368 A AU2014256368 A AU 2014256368A AU 2014256368 A AU2014256368 A AU 2014256368A AU 2014256368 A1 AU2014256368 A1 AU 2014256368A1
Authority
AU
Australia
Prior art keywords
mast
lift
stage
attachment
hanger
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
AU2014256368A
Other versions
AU2014256368B2 (en
Inventor
Nico Berns
Norbert Bruenell
Joost Erinkveld
Paul Smulders
Peter Van den Hurk
Stefan Van der Cruijsen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hyster Yale Group Inc
Original Assignee
Nacco Materials Handling Group Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nacco Materials Handling Group Inc filed Critical Nacco Materials Handling Group Inc
Publication of AU2014256368A1 publication Critical patent/AU2014256368A1/en
Assigned to Hyster-Yale Group, Inc. reassignment Hyster-Yale Group, Inc. Alteration of Name(s) of Applicant(s) under S113 Assignors: NACCO MATERIALS HANDLING GROUP, INC.
Application granted granted Critical
Publication of AU2014256368B2 publication Critical patent/AU2014256368B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075Constructional features or details
    • B66F9/20Means for actuating or controlling masts, platforms, or forks
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075Constructional features or details
    • B66F9/07504Accessories, e.g. for towing, charging, locking
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075Constructional features or details
    • B66F9/07509Braking
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075Constructional features or details
    • B66F9/08Masts; Guides; Chains

Landscapes

  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Structural Engineering (AREA)
  • Civil Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Forklifts And Lifting Vehicles (AREA)
  • Lift-Guide Devices, And Elevator Ropes And Cables (AREA)

Abstract

Abstract Devices and methods to relieve lift chains from being maintained under constant, or nearly constant, tension are provided. 33 a 2 35

Description

1000829454 P/00/01 1 Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Lift chain tension relieving devices and methods The following statement is a full description of this invention, including the best method of performing it known to us: 1000829454 LIFT CHAIN TENSION RELIEVING DEVICES AND METHODS Technical Field [00011 The field of the present disclosure relates to accessories for lift truck masts. [00021 The present inventors have recognized that lift chains on certain lift truck masts are typically under constant, or nearly constant, tension For example, when the mast is not fully lowered with an attachment resting on the ground the lift chains are under constant tension For some lift trucks in certain applications, such as empty container handling the lift chains rarely, if ever, are relieved from being tensioned. Some lift truck lift chains therefore carry a relatively large proportion of the rated load for a lift truck, even when not lifting a load, because of the construction, kinematics, dimensions, and eight of attachments secured to the mast. [00031 The present inventors have also recognized that maintaining lift chains under constant, or nearly constant, tension inhibits effective lubrication of such chains. The present inventors have also recognized that maintaining lift chains under constant, or nearly constant, tension typically reduces lift chain life. [00041 To address the above, and other problems, the present inventors created devices and methods to relieve lift chains from being maintained under constant, or nearly constant, tension Brief Description of the Drawings [00051 Fig. 1 illustrates a rear right-hand side isometric view of a mast hanger embodiment. [00061 Fig. 2 illustrates a front left-hand side isometric view of the mast hanger of Fig. 1 on a lift truck mast. [00071 Fig. 3 illustrates a left-hand side cut away view of the mast hanger of Fig. 1 on a lift truck mast. [00081 Fig. 4 illustrates a rear left-hand side isometric view of another mast hanger embodiment at a non-mast receiving position [00091 Fig. 5 illustrates a rear left-hand side isometric view of the mast hanger embodiment of Fig. 4 at a mast receiving position 2 1000829454 [00101 Fig. 6 illustrates a flow chart of an exemplary method of relieving tension from lift chains. [00111 Fig. 7 illustrates a flow chart of another exemplary method of relieving tension from lift chains. [00121 Fig. 8 illustrates an exemplary schematic of a mast hanger system interface. Detailed Description [00131 A device for facilitating lift chain tension relief is illustrated in Figs. 1-3. A mast hanger 10 includes a first support 15 and a second support 20 that are connected by an optional spacer 25. E ach of the first support 15 and the second support 20 include a mast receiving formation 30, an attachment receiving formation 35, and an optional mast attachment 40. In the embodiment illustrated in Fig. 1, the mast receiving formation 30 comprises a raised portion 31 and a lip 32 that forms a pocket 33. The attachment receiving portion 35 comprises a sloped shelf 36. The mast attachment 40 comprises a hook-shape. Preferably, each of the first support 15 and the second support 20 are integrally formed with a mast receiving formation 30, an attachment receiving formation 35, and a mast attachment 40, for example, by casting forging cutting, or stamping using ductile iron, steel, or other suitable material. Optionally, the first support 15 and the second support 20 may be formed by providing an elongate bar and securing one or more of a mast receiving formation 30, an attachment receiving formation 35, and a mast attachment 40 to each elongate bar by gelding bolting or other suitable attachment. [00141 In other embodiments, a mast hanger 10A includes only a mast receiving formation 30A (Fig. 1A). In other embodiments, a mast hanger 1OB includes only an attachment receiving formation 35b (Fig. 1 B). [00151 The optional spacer 25 is preferably secured to each of the first support 15 and the second support 20 via bolts, welds, or other suitable attachment. The spacer 25 may be constructed from a relatively lightweight material such as sheet metal or a rigid plastic. [00161 Fig. 2 illustrates the mast-hanger 10 of Fig. 1 installed on a tvw stage mast 45 of a lift truck 50 (partially illustrated) where the second stage is removed for clarity. Optionally, the mast may include more than tw stages and the mast hanger 10 may include one or more mast receiving formations, such as mast receiving formation 30. The mast-hanger 10 hangs on a cross member 55 of the tv stage mast 45 via the mast attachments 40. Optionally, for 3 1000829454 a mast with more than two stages, multiple mast-hangers, such as mast hanger 10 or mast hanger 100, maybe provided, preferably with one mast-hanger on a fixed stage and one or more mast hangers on one or more moveable stages. A lip 26 (Fig. 1) of the optional spacer 25 facilitates maintaining the first support 15 and the second support 20 in contact with cross members 55 and 60 by engaging a back-side of the cross member 55. Optionally, the mast-hanger 10 may be bolted, welded, or otherwise suitably secured in place. In some embodiments where the first support 15 and the second support 20 are secured in place, one or both of the optional spacer 25 and mast attachment 40 may be omitted. In other embodiments, the optional spacer 25 may be omitted even if the mast-hanger 10 is not bolted, welded or otherwise fastened to the two stage mast 45. [00171 Fig. 3 illustrates the mast-hanger 10 of Fig. 1 supporting the second stage 65 of the two stage mast 45 and an attachment 70. By the nature of their design, construction, kinematics, dimensions, weight, or other relevant characteristic, some attachments do not permit a lift truck operator to fully lower the attachment to the ground, thus removing some or all of the tension in the lift chains. For example, attachments designed to handle empty cargo containers typically cannot be set on the ground and thus do not permit a lift truck operator to fully lower such attachments. [00181 Pocket 33 is shaped and sized to receive the second stage 65 of the two stage mast and thus transfer some or all of the weight of the second stage 65 from the lift chains to the cross member 55. Sloped shelf 36 is shaped and sized to receive the attachment 70 and thus transfer some or all of the weight of the attachment 70 from the lift chains to the cross member 55. In the illustrated embodiment, the attachment 70 includes an integrated carriage. However, some carriages are not integrated with an attachment, and in certain embodiments the sloped shelf 36, or another suitable portion of a mast-hanger, is preferably shaped and sized to receive such a non-integrated carriage, a non-integrated attachment, or both. An attachment receiving portion is therefore a portion of a mast-hanger that is (1) sized and shaped to receive an integrated carriage and attachment, (2) sized and shaped to receive a non-integrated carriage, (3) sized and shaped to receive a non-integrated attachment, or (4) sized and shaped to receive a non-integrated carriage and a non-integrated attachment. Preferably, the tw stage mast 45 is oriented in a substantially vertical position to facilitate transferring some or all of the weight of the second stage 65 and of the attachment 70 to the cross member 55. Optionally, the mast receiving formation 30, the attachment receiving 4 1000829454 formation 35, or both maybe shaped, sized and located such that the two stage mast 45 may be substantially vertical without some or all of the weight of one or both of the second stage 65 and the attachment 70 creating stress, and thus tension, on the lift chains. [00191 When a mast-hanger, such as mast-hanger 10, is used with a lift truck equipped with an attachment that does not permit the operator to fully lower the attachment to the ground, such mast-hanger provides a location at which the mast, the carriage, the attachment, or any combination thereof, including all three, may be placed to remove all, substantially all, or a portion of the tension from the lift chains. When all, substantially all, or a portion of the tension is removed from the lift chains, such lift chains may have an extended life compared to lift chains of an equivalent lift truck equipped with the same attachment, but without a mast-hanger. For example, lift chain life maybe extended because the relaxed tension may permit lubrication oil to flow into the links better than if such tension mere not removed from the lift chains. As another example, lift chain life may be extended because relaxing or removing tensions from such lift chains reduces internal stresses within such lift chains. [00201 Another device for facilitating lift chain tension relief is illustrated in Figs. 4 and 5. Details of the lift truck 150 and mast 145 are omitted for clarity. Likewise, no attachment is illustrated on the mast 145. The mast-hanger 100 includes two supports comprising a first beam 115 and a second beam 120 that are supported by a first stage 146 of a multi-stage mast 145. In the illustrated example, the multi-stage mast 145 is a two-stage mast, however more than two stages maybe included, or the mast may not be a multi-stage mast and only one stage maybe included. Beams 115 and 120 are supported by beam supports 125 and 130, respectively, such that beams 115 and 120 are moveable with respect to the first stage of the multi-stage mast 145. In the illustrated example, beams 115 and 120 slide with respect to beam supports 125 and 130, however beams 115 and 120 may rotate or pivot with respect to beam supports 125 and 130, or may otherwise be suitably configured for movement with respect to the first stage 146 of the multi-stage mast 145. [00211 Beams 115 and 120 may be manually moveable, or may be moveable via an automated device, such as hydraulic extension cylinders 135, an electric linear actuator, an electric motor, or other suitable motive source. Two supports are illustrated, but some embodiments include only one support and other embodiments include thme or four supports. 5 1000829454 [00221 Mast hanger 100 optionally includes one or more signal devices, such as lights 805 and 815 (Fig. 8). A signal device may be mounted on a portion of a lift truck such as an operator compartment, or other suitable location where the signal device may be readily viewed by the lift truck operator. In other embodiments, the signal device may include a hand-held electronic device that tirelessly communicates wth a mast hanger and provides operational information regarding the mast hanger via a screen, such as by displaying printed information or graphic information [00231 The signal device communicates wth the mast hanger, such as mast hanger 100, and is configured to provide information regarding the operational status of the mast hanger to someone viewing the signal device. In the embodiment illustrated in Figs. 4 and 5, the mast hanger 100 is associated with one or more position sensors, such as optical sensors, an encoder associated with the motive source, one or more Hall-effect sensors and one or more magnets, or other suitable position sensor for providing a signal indicative of the position of the beams 115 and 120. One signal indicates that the beams 115 and 120 are in a fully retracted, or non-mast receiving position (illustrated in Fig. 4) where the beams 115 and 120 do not interfere wth lowering the second stage 155 of the mast 145. Another signal indicates that the beams 115 and 120 are in a fully extended, or mast receiving position (illustrated in Fig. 5) where the beams 115 and 120 inhibit lowering the second stage 155 of the mast 145. [00241 Additional sensors that detect the position of the mast 145, an attachment connected to the mast, or both optionally communicate with the signal device. By knowing the position of the mast 145, an attachment, or both, the signal device may indicate to the operator when a mast hanger receives the mast 145, an attachment, or both and provide a signal to inform the operator that the mast 145 should not be lowered any further. Optionally, an indication that a mast hanger receives the mast 145, an attachment, or both may be communicated to a processor on-board a lift truck and the processor may inhibit or prevent the operator from further lowering the mast 145, an attachment, or both. Inhibiting or preventing further lowering of the mast 145, an attachment, or both once received by a mast hanger may prevent the lift chains from becoming excessively slack which may cause the lift chains to become damaged or move out of alignment, or may cause unwanted stress from a sudden impact on the chains when the mast 145, an attachment, or both are lifted from the mast hanger. 6 1000829454 [00251 Optionally, a strain gauge or other suitable eight bearing determination device may be associated with the beams 115 and 120 to provide an additional signal that the beams 115 and 120 are bearing at least a portion of the eight of the second stage 155 of the mast 145 and of any attachment and load connected to the mast 145. When an optional weight bearing determination device is included, an illuminated light or other suitable indicator that indicates that the beams 115 and 120 are at the fully extended position may onlybe illuminated if the beams 115 and 120 are at the fully extended position and are bearing eight, or there may be one indicator, such as an illuminated light, that indicates that the beams 115 and 120 are at the fully extended position and another indicator, such as an illuminated light, that indicates that the beams 115 and 120 are bearing eight. [00261 Optionally, a shock absorber, such as an impact pad, damper or other suitable device for absorbing some of the shock resulting from contacting the mast 145, an attachment, or both with the beams 115 and 120 maybe included For example, a shock absorber 122 (Fig. 4) maybe provided on a top surface of beams 115 and 120. Shock absorber 122 maybe a pad of resilient material, such as natural rubber, soft plastic, or other suitable material, that is affixed to the beams 115 and 120; or shock absorber 122 may include dampening devices such as springs, resilient absorbers or other suitable devices interposed between a contact plate and the beam 115 or 120. Likewise, a shock absorber 122, or other suitable device, maybe located on the top side of pocket 33, sloped shelf 36, or both (Fig. 1). [00271 Fig. 6 illustrates a flowchart for a method of facilitating lift chain tension relief. At step 600, a lift truck operator raises a second stage of a multi-stage mast and an attachment above the position of a mast-hanger to an initial position For example, an initial position maybe any position above pockets 33 (Fig. 1) or the beams 115 and 120 (Fig. 4), but is preferably a position that is 5 cm to 25 cm above the pockets 33 or the beams 115 and 120. Optional step 605 involves moving the mast-hanger into a mast receiving position Step 605 is optional for mast-hangers that may be maintained in a mast receiving position such as mast-hanger 10, for example. At step 610, the lift truck operator lowers at least the second stage of a multi-stage mast and optionally an attachment onto the mast hanger. At step 615, the lift truck operator continues to apply a loier command to the mast to relieve at least some of the tension from the lift chains as the eight of the attachment and at least the second stage of the multi-stage mast are transferred to the first stage of the multi-stage mast 7 1000829454 via the mast-hanger. In other words, the attachment does not contact the ground at step 615. [00281 With reference to Figs. 7 and 8, an exemplary process for operating a mast hanger that includes beams 115 and 120 is described With the engine of a lift truck running, an operator activates the park brake at step 700. The operator then manipulates key switch 800 to the "on" position to activate the mast hanger system at step 705. A processor associated with the mast hanger system detects the activation of the park brake, and switches blue light 805 on at step 710 to indicate that the mast hanger system is active. If the processor does not detect that the park brake has been activated, the mast hanger system may prompt the operator to activate the park brake, for example, by flashing blue light 805. Preferably, any time there is an error with operation of the mast hanger system detected by the processor, the blue light 805 is flashed The processor activates a park brake lock at step 715 to prevent disengagement of the park brake 4ile the mast hanger system is active. [00291 At step 720 the operator moves an attachment connected to the mast 145 into an initial position, for example, the operator may move a spreader for moving cargo containers to a position that is in the range of 5 cm to 25 cm above the beams 115 and 120, and preferably approximately 12 cm, and at step 725 the processor detects when the attachment is in an initial position by receiving input from a proximity switch or other suitable sensor positioned and configured to send a signal when the attachment is in the initial position Optionally, the processor may cause the attachment to move into an initial position and may receive information from a proximity swtch or other suitable sensor associated with the mast 145 to indicate when the attachment is in the initial position in response to receiving a signal, for example from a move to position switch (not illustrated) manipulated by the operator, from the extend switch 810, or from another suitable signal source. [00301 At step 730 the processor activates a lowering interrupt function that inhibits or prevents the operator from lovring the attachment, and enables the extend switch 810. At step 735 the operator activates the extend switch 810 and the processor activates an automated device to extend the beams 115 and 120 to their extended positions. Optionally, the processor may automatically activate a lowering interrupt function and cause the beams 115 and 120 to extend in response to receiving a signal that the attachment is in an initial position above the beams 115 and 120, in response to receiving a signal from the extend switch 810, or in response to another suitable signal. 8 1000829454 [00311 At step 740, the processor determines whether the beams 115 and 120 are at the retracted position, for example, via signals sent from a proximity switch, Hall effect sensor, or other suitable sensor, and if not, activates a reduced lowering speed function that limits the speed at which an attachment may be lowered At step 745, the processor determines whether the beams 115 and 120 are at their extended positions, for example, via signals sent from a proximity switch, Hall effect sensor, or other suitable sensor, and if so, disables the extend switch 810 and deactivates the lowering interrupt function. At step 750, the operator lovers the attachment until the attachment, the mast 145, or both, contact the beams 115 and 120. Optionally, the processor may automatically activate a reduced lowering speed, deactivate the lowering interrupt function, and lo1er the attachment until the attachment, the mast 145, or both, contact the beams 115 and 120 in response to determining that the beams 115 and 120 are at their extended positions, or in response to another suitable signal. [00321 Contact of the attachment, the mast 145, or both, with the beams 115 and 120 is detected at step 755, for example, via signals sent from a proximity switch, strain gauge, or other suitable sensor, and the processor activates the lowering interrupt function and an indicator, such as gmen light 815, to indicate to the operator that the attachment, the mast 145, or both are in position on the beams 115 and 120. The processor also deactivates the retract switch 820. [00331 To disengage the mast hanger system, the operator lifts the attachment, the mast 145, or both from the beams 115 and 120 at step 760. At step 765, the processor detects that the attachment, the mast 145, or both are no longer supported by the beams 115 and 120, for example, via signals sent from a proximity switch, strain gauge, or other suitable sensor, and enables the retract switch 820. The processor also disables the lowering interrupt function and tums the green light 815 off, thus indicating to the operator that the attachment, the mast 145, or both are no longer supported by the beams 115 and 120. The operator manipulates the retract switch 820 at step 770 and the beams 115 and 120 are moved to their retracted positions. Optionally, the processor may lift the attachment, the mast 145, or both from the beams 115 and 120, detect that the attachment, the mast 145, or both are no longer supported by the beams 115 and 120, disable the lowering interrupt function, turn the green light 815 off, and move the beams 115 and 120 to their retracted positions in response to receiving a signal from the retract switch 820, or from another suitable signal source. 9 1000829454 [00341 At step 775, the processor detects whether the beams 115 and 120 are at their extended positions, for example, via signals sent from a proximity switch, hall effect sensor, or other suitable sensor, and if not, enables the extend switch 810 and the lowering interrupt function. At step 780, the processor detects whether the beams 115 and 120 are at their retracted positions, for example, via signals sent from a proximity switch, hall effect sensor, or other suitable sensor, and if so, deactivates the reduced lowering speed function, deactivates the lowering interrupt function, enables the extend switch 810, preferably only if the attachment, the mast 145, or both are in an initial position above the beams 115 and 120, and disables the retract switch 820. [00351 The operator deactivates the mast hanger system at step 785 by manipulating the key switch 800 to the off position At step 790, the processor deactivates the blue light 805 to indicate to the operator that the mast hanger system is deactivated and deactivates the park brake lock [00361 While the above has been described as a series of steps, the aggregation and order of the described operations is not important, and various operations maybe combined or omitted. 10

Claims (14)

1. A mast-hanger comprising a support mounted to a first stage of a lift mast; theremin the support includes a mast receiving portion or an attachment receiving portion; wherein, if included, the mast receiving portion is sized, shaped, and positioned to (i) receive a second stage of the lift mast and (ii) facilitate releasing tension from lift chains of the lift mast by transferring at least some of the eight of the second stage of the lift mast to the first stage of the lift mast via the support; and wherein, if included, the attachment receiving portion is sized, shaped, and positioned to (i) receive an attachment borne by the lift mast and (ii) facilitate releasing tension from lift chains of the lift mast by transferring at least some of the weight of the attachment to the first stage of the lift mast via the support.
2. A mast-hanger according to claim 1, wherein the support includes both a mast receiving portion and an attachment receiving portion
3. A mast-hanger according to claim 1, wherein: the support comprises a first support and a second support each mounted to the first stage of the lift mast; the first support includes a mast receiving portion or an attachment receiving portion; the second support includes a mast receiving portion if the first support includes a mast receiving portion or an attachment receiving portion if the first support includes an attachment receiving portion; if included, the mast receiving portions are sized, shaped, and positioned to (i) receive a second stage of the lift mast and (ii) facilitate releasing tension from lift chains of the lift mast by transferring at least some of the eight of the second stage of the lift mast to the first stage of the lift mast via the first and second supports; and if included, the attachment receiving portion is sized, shaped, and positioned to (i) receive an attachment borne by the lift mast and (ii) facilitate releasing tension from lift chains of 11 1000829454 the lift mast by transferring at least some of the eight of the attachment to the first stage of the lift mast via the first and second supports.
4. A mast-hanger according to claim 3, wherein the first support includes both a mast receiving portion and an attachment receiving portion; and the second support includes both a mast receiving portion and an attachment receiving portion
5. A mast-hanger according to claim 4, further comprising a mast attachment portion associated with the first support; and a mast attachment portion associated with the second support; w~heremin the mast attachment portions associated with the first and second supports are shaped and sized to engage a cross member of the lift mast such that the mast-hanger hangs on the cross member.
6. A mast-hanger according to claim 5, further comprising a spacer connected between the first support and the second support.
7. A mast-hanger according to claim 6, wherein the spacer comprises a lip that is sized and shaped to engage a back-side of the cross member to hinder the mast-hanger from swinging.
8. A mast-hanger according to claim 4, wherein the first and second supports are moveably mounted to the first stage of the lift mast.
9. A mast-hanger according to claim, further comprising a motive source operatively connected to the first and second supports to move the first and second supports between a retracted position and an extended position
10. A mast-hanger according to claim 9, further comprising a signaling device operatively associated wth the first and second supports to indicate a status of the first and second supports to an operator. 12 1000829454
11. A mast-hanger according to claim 4, further comprising a shock absorber on each of the first and second supports.
12. A method for operating a lift truck equipped with a mast hanger comprising receiving a lift command and raising a second stage of a multi-stage mast above a mast hanger to an initial position in response to receiving the lift command; receiving a loier command and lowering a second stage of the multi-stage mast onto the mast hanger in response to receiving the loier command; and continuing to receive the lover command and operating a lowering mechanism of the multi stage mast to relieve at least some of the tension from the lift chains as the weight of the second stage of the multi-stage mast is transferred to a first stage of the multi-stage mast via the mast-hanger in response to continuing to receive the lower command.
13. A method for operating a lift truck equipped with a mast hanger according to claim 12, further comprising receiving an extension command and moving the mast-hanger into a mast receiving position in response to receiving the extension command
14. A method for operating a lift truck equipped with a mast hanger according to claim 13, further comprising receiving a second lift command and raising the second stage of the multi-stage mast off the mast-hanger in response to receiving the second lift command; and receiving a tract command and moving the mast-hanger into a non-mast receiving position in response to receiving the tract command 13
AU2014256368A 2013-11-05 2014-10-30 Lift chain tension relieving devices and methods Active AU2014256368B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201361900015P 2013-11-05 2013-11-05
US61/900,015 2013-11-05

Publications (2)

Publication Number Publication Date
AU2014256368A1 true AU2014256368A1 (en) 2015-05-21
AU2014256368B2 AU2014256368B2 (en) 2019-04-04

Family

ID=51862156

Family Applications (1)

Application Number Title Priority Date Filing Date
AU2014256368A Active AU2014256368B2 (en) 2013-11-05 2014-10-30 Lift chain tension relieving devices and methods

Country Status (4)

Country Link
US (2) US10329130B2 (en)
EP (2) EP2868620B1 (en)
CN (2) CN107032264B (en)
AU (1) AU2014256368B2 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10562746B2 (en) * 2016-10-28 2020-02-18 Hyster-Yale Group, Inc. Mast support device
CN109231032B (en) * 2018-10-15 2022-05-10 周宁县善长祥农业机械研发有限公司 Agricultural crane
US11565923B2 (en) 2019-02-19 2023-01-31 Crown Equipment Corporation Chain slack detection system

Family Cites Families (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1402307A (en) * 1920-10-07 1922-01-03 Eloise H Metcalf Closet attachment
US2456320A (en) * 1947-02-24 1948-12-14 Ross Carrier Company Lift truck
US2581791A (en) * 1949-06-18 1952-01-08 Shepard Co Lewis Industrial lift truck
GB870361A (en) 1959-03-09 1961-06-14 Multi Lift Co Load hoisting mast
US3907142A (en) 1971-08-26 1975-09-23 Forrest D Welch Lifting attachment for a crane
US3786902A (en) * 1972-05-08 1974-01-22 Knickerbocker Co Load-lifting mechanism for a lift truck
US3851732A (en) * 1973-02-08 1974-12-03 Towmotor Corp Mast and carriage for a lift truck
US3974927A (en) * 1974-07-15 1976-08-17 Little Giant Products, Inc. Side shifter assembly for lift trucks
US4034855A (en) * 1975-09-25 1977-07-12 Caterpillar Tractor Co. Suspended guide rollers
US4030568A (en) * 1976-03-24 1977-06-21 Caterpillar Tractor Co. High visibility mast for lift trucks
US4307792A (en) 1980-03-18 1981-12-29 J. I. Case Company Forklift roller mast lock
US4544323A (en) * 1982-09-03 1985-10-01 Malin James I Quick coupling and lift device
JPH0211439Y2 (en) 1984-11-09 1990-03-22
JPS62144296U (en) 1986-02-28 1987-09-11
US4896748A (en) * 1988-05-27 1990-01-30 Caterpillar Industrial Inc. Full free lift mast assembly
US4921075A (en) * 1989-02-21 1990-05-01 Teledyne Princeton, Inc. Fork lift
JPH0346999A (en) 1989-07-13 1991-02-28 Toyota Autom Loom Works Ltd Cargo handling gear for forklift
DE19855202B4 (en) * 1997-12-01 2006-10-26 Nissan Motor Co., Ltd., Yokohama Pole arrangement and equipped with a mast lifting truck
EP1481942B1 (en) * 2003-05-30 2011-08-31 Moffett Research and Development Limited A truck mounted forklift with double-acting freelift mast
JP2004359406A (en) * 2003-06-04 2004-12-24 Toyota Industries Corp Mast structure of forklift and its manufacturing method
JP4806985B2 (en) 2005-07-15 2011-11-02 株式会社豊田自動織機 Industrial vehicle lift device
CN100575239C (en) 2007-06-14 2009-12-30 王树生 Wheel is to piler
DE102008035583A1 (en) 2008-07-30 2010-02-11 Liebherr-Werk Ehingen Gmbh Telescopic boom for crane i.e. mobile crane, has anchoring cylinders arranged in support braces for defined anchoring of suspension rope, where free ends of suspension rope are fastened to anchoring cylinders
CN201485228U (en) 2009-08-31 2010-05-26 晋正自动化工程(浙江)有限公司 Stack machine for ship-type tubes
CN201512390U (en) * 2009-09-10 2010-06-23 浙江杭叉工程机械集团股份有限公司 Double-deck tumbling electric fork truck
US8777545B2 (en) * 2009-10-20 2014-07-15 Bright Coop, Inc. Free lift mast for truck mounted forklift
CN101913546B (en) * 2010-07-26 2012-12-26 三峡大学 Vehicle CNG gas cylinder loading and unloading and carrying device and loading and unloading method
CN201777852U (en) * 2010-08-15 2011-03-30 芜湖瑞创叉车有限公司 Fork truck working device
CN202575884U (en) * 2012-04-17 2012-12-05 安徽合力股份有限公司 Forklift truck portal frame assembly with anti-shock chain
CN202785500U (en) * 2012-08-15 2013-03-13 新疆众和股份有限公司 Collecting and conveying device of electrode foil finished foil roll
CN103232011B (en) * 2013-05-16 2015-12-09 烽火通信科技股份有限公司 A kind of optical cable metal belt transport trolley

Also Published As

Publication number Publication date
CN104787689A (en) 2015-07-22
AU2014256368B2 (en) 2019-04-04
EP3868701B1 (en) 2022-10-05
US10329130B2 (en) 2019-06-25
CN104787689B (en) 2017-03-22
CN107032264B (en) 2019-11-12
EP3868701A1 (en) 2021-08-25
CN107032264A (en) 2017-08-11
US10773937B2 (en) 2020-09-15
US20150122585A1 (en) 2015-05-07
EP2868620A1 (en) 2015-05-06
EP2868620B1 (en) 2021-03-10
US20190263647A1 (en) 2019-08-29

Similar Documents

Publication Publication Date Title
US10773937B2 (en) Lift chain tension relieving devices and methods
JP7288095B2 (en) Commercial vehicle tire hub drum attachment/detachment device
CN105883673A (en) Rapid maneuvering loading and unloading transport cart for containers
KR101507626B1 (en) Camera fixing device of forklift for safety
CN101670805A (en) Truck with loading crane with super-high lifting capability
CN202575884U (en) Forklift truck portal frame assembly with anti-shock chain
KR101643004B1 (en) Device for adjusting fork transfer section for a forklift truck
KR101633267B1 (en) Self loader for small size truck
CN204151024U (en) A kind of fork truck lifting oil cylinder fixed mechanism
CN107150981B (en) A kind of lifting machine with dual anti-falling protection function
CA2960065C (en) Crane for lifting and transporting loads comprising a roll-over protection system
CA2960061C (en) Crane for lifting and transporting loads
JPS63277194A (en) Balance weight operating device for conuter balance crane
CN112978615A (en) Manual hydraulic vehicle for storage
CN204688237U (en) Driver's cab turnover inhibiting device
CN202106812U (en) Disassembly and assembly vehicle for band tyre
CN202130999U (en) Hoisting device for sliding loader
CN221027568U (en) Electric fork truck plays to rise portal and falls detection device
CN101531126B (en) Device for assembling and disassembling tyre during inflation detection of large-sized engineering tyre
CN101670978B (en) Single-layer trolley platform of tire crane
US9505332B2 (en) Vehicle recovery tool
CN201362146Y (en) Assembling and disassembling tire device when detecting aeration of large engineering tire
CN202449806U (en) Suspended pedal of forward fork lift
KR20040077616A (en) Duplicated span spring of which separated type for cargo trucks, thereof its manufactured method.

Legal Events

Date Code Title Description
FGA Letters patent sealed or granted (standard patent)