US-12617620-B2 - Load carrying system and method

US12617620B2US 12617620 B2US12617620 B2US 12617620B2US-12617620-B2

Abstract

A dolly has a frame; a plurality of rolling elements mounted on the frame for rotation about respective rotational axes generally parallel to the ground surface and defining a contact footprint of the dolly on the ground surface. The axes extend in a plane between a load contacting surface of the dolly and the ground surface at a distance between 30% and 50% of a height defined between the load contacting surface of the dolly and the ground surface. A swivel platform defines the load contacting surface extending at an elevation above the frame and mounted on the frame for rotation about a platform axis located within the contact footprint. An actuator unit is drivingly engaged to at least two rolling elements of the plurality of rolling elements, the at least two rolling elements disposed on opposite sides of the swivel platform. An on-board controller unit is operable to actuate the actuator unit.

Inventors

Charles-Éric RAYMOND
Pascal BEAULIEU
Anne-Marie COUPAL
Hugo SOUCY
Louis MASSICOTTE-MORISSETTE
Marc-André TETRAULT
Francis Roy
Olivier Julien
Benoît SERRANO-PARENT
Alexandre CHARBONNEAU
Mathieu LABELLE
Francis BOUTHILLETTE
Brayaan DIAZ
Tommy FORTIER
David PETITCLERC
Laurier Tremblay

Assignees

9428-3421 Québec inc.

Dates

Publication Date: 20260505
Application Date: 20211126

Claims (20)

1 . A dolly for transporting a load on a ground surface, the dolly comprising: a frame; a plurality of rolling elements mounted on the frame for rotation about respective rotational axes, the plurality of rolling elements defining a contact footprint of the dolly on the ground surface; a swivel platform defining a load contacting surface at a top of the dolly, the swivel platform extending at an elevation above the frame, the swivel platform mounted on the frame for rotation about a platform axis, the platform axis located within the contact footprint; an actuator unit including a first motor and a second motor, the first motor and the second motor drivingly engaged respectively to at least two rolling elements of the plurality of rolling elements, the at least two rolling elements drivingly engaged respectively to the first motor and the second motor disposed on opposite sides of a meridional plane of the swivel dolly; and an on-board controller unit operatively connected to the actuator unit, the on-board controller unit operable to actuate the actuator unit; wherein the frame defines a beam, the swivel platform is located over the beam, the first motor and the second motor are disposed on opposite sides of the beam.
2 . The dolly as defined in claim 1 , wherein the first motor and the second motor are at least partially recessed within the frame, a first torque transmitter axially mounted to the first motor and a second torque transmitter axially mounted to the second motor, the first torque transmitter and the second torque transmitter each coupled to the frame.
3 . The dolly as defined in claim 1 , wherein the frame is a single block frame, the single block frame defining a first cut-out and a second cut-out located at least partially under the swivel platform, the beam extending in a transverse plane intersecting with the swivel platform, the beam defining a common wall between the first cut-out and the second cut-out the single block frame further defining other cut-outs receiving the rolling elements.
4 . The dolly as defined in claim 1 , wherein the plurality of rolling elements have a wheelbase defined between adjacent ones of the plurality of rolling elements on a same side of a meridional plane of the dolly, and a track width defined between respective contact points of opposite ones of the plurality of rolling elements on opposite sides of the meridional plane, a ratio of the wheelbase over the track width is 0.25±0.1.
5 . The dolly as defined in claim 4 , wherein the dolly has a width transverse to a meridional plane of the dolly, a ratio of the track width over the width is 0.9±0.09, and wherein the dolly has a length L along the meridional plane, wherein the wheelbase is smaller than 0.3L±0.1L.
6 . The dolly as defined in claim 1 , wherein the load contacting surface of the swivel platform extends in a plane PPB above a tangential plane PPT passing by a top of the respective ones of the plurality of rolling elements, wherein an offset between the plane PPB and the tangential plane PPT is between 5% and 25% of a height of the dolly defined between the load contacting surface of the dolly and the ground surface.
7 . The dolly as defined in claim 1 , wherein the dolly includes a force sensor coupled to the frame, the force sensor connected to the on-board controller unit to transmit signals indicative of a load applied on the swivel platform.
8 . The dolly as defined in claim 7 , wherein the force sensor includes at least one strain gauge coupled to the frame, the strain gauge part of a Wheatstone bridge circuit.
9 . The dolly as defined in claim 1 , wherein the swivel platform includes an angular encoder, the angular encoder transmitting a signal indicative of an angular position of the swivel platform relative to the frame, about the platform axis.
10 . The dolly as defined in claim 1 , wherein the actuator unit includes a motor and a torque transmitter drivingly engaged to a respective one of the at least two rolling elements.
11 . The dolly as defined in claim 1 , wherein the dolly includes at least two pairs of axles supporting respective ones of the plurality of rolling elements, the at least two pairs of axles disposed on opposite sides of a meridional plane of the dolly, the at least two pairs of axles each including one of the at least two rolling elements drivingly engaged to the actuator unit, the axles of each one of the at least two pairs of axles are drivingly engaged by a torque transmitter.
12 . The dolly as defined in claim 1 , wherein the dolly includes a casing enclosing the on-board controller unit, the casing projecting outwardly from an outer periphery of the frame the casing is coupled to the frame in a cantilevered fashion, a clearance gap is defined between the casing and the ground surface, the clearance gap greater than that between the frame and the ground surface.
13 . A dolly for transporting a load on a ground surface, the dolly comprising: a frame; a plurality of rolling elements mounted on the frame for rotation about respective rotational axes, the plurality of rolling elements defining a contact footprint of the dolly on the ground surface; a swivel platform defining a load contacting surface, the swivel platform extending at an elevation above the frame, the swivel platform mounted on the frame for rotation about a platform axis, the platform axis located within the contact footprint; an actuator unit configured to displace the dolly on the ground surface, the actuator unit including a first motor and a second motor, the first motor drivingly engaged to at least a first one of the plurality of rolling elements, the second motor drivingly engaged to at least a second one of the plurality of rolling elements, the first one of the plurality of rolling elements and the second one of the plurality of rolling elements disposed on opposite sides of the swivel platform; an on-board controller unit operatively connected to the actuator unit, the on-board controller unit operable to actuate the actuator unit; and wherein the frame includes a rigidifying structure extending in a transverse plane intersecting with the swivel platform, the first motor and the second motor disposed on opposite sides of the rigidifying structure.
14 . The dolly as defined in claim 13 , wherein the first motor has a first rotational axis and the second motor has a second rotational axis, the first rotational axis and the second rotational axis parallel with the transverse plane.
15 . The dolly as defined in claim 14 , wherein the first rotational axis and the second rotational axis are parallel with the rotational axes of the plurality of rolling elements.
16 . The dolly as defined in claim 13 , wherein the frame defines a first hollowed portion and a second hollowed portion extending at least partially under the swivel platform, the first hollowed portion receiving the first motor and the second hollowed portion receiving the second motor, the rigidifying structure defining a common wall between the first hollowed portion and the second hollowed portion.
17 . The dolly as defined in claim 13 , wherein the actuator unit includes a first torque transmitter axially mounted to the first motor and a second torque transmitted axially mounted to the second motor, the first torque transmitter and the second torque transmitter each coupled to the frame.
18 . The dolly as defined in claim 17 , wherein the first motor and the first torque transmitter are aligned along a common axis that is parallel with the rotational axis of at least the first one of the plurality of rolling elements.
19 . The dolly as defined in claim 13 , wherein the rotational axes of the plurality of rolling elements extend in a plane PPA extending between the load contacting surface of the dolly and the ground surface, a height defined between the load contacting surface of the dolly and the ground surface, the plane PPA extending at a distance between 30% and 50% of the height.
20 . The dolly as defined in claim 1 , wherein the rotational axes of the plurality of rolling elements extend in a plane PPA extending between the load contacting surface of the dolly and the ground surface, a height defined between the load contacting surface of the dolly and the ground surface, the plane PPA extending at a distance between 30% and 50% of the height.

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application claims the priority of U.S. Patent Application No. 63/118,703, filed on Nov. 26, 2020, and incorporated herein by reference. TECHNICAL FIELD The application relates generally to dollies and, more particularly, dollies systems and methods for transporting heavy objects. BACKGROUND OF THE ART Equipment carriers, also known as dollies, industrial skates or motorized trolleys are used to lift and/or transport heavy objects in facilities. For instance, heavy objects such as large/cumbersome machineries, containers, etc. may have to be moved in facilities or on sites (e.g. construction sites). Single carriers may be used to move large and heavy objects. Such carriers may be cumbersome as a result of their large dimensions and/or not versatile when it comes to transport equipment of various sizes, geometries, and/or loads. A group of carriers may be used to displace a single equipment. GPS technologies may assist to control and/or detect the relative position between them. However, such technologies may have limited precisions on short distances, such as distances below 10-meters between the carriers. SUMMARY In a first aspect, there is provided a dolly for transporting a load on a ground surface, the dolly comprising: a frame; a plurality of rolling elements mounted on the frame for rotation about respective rotational axes generally parallel to the ground surface, the plurality of rolling elements defining a contact footprint of the dolly on the ground surface, the rotational axes extending in a plane PPA extending between a load contacting surface of the dolly and the ground surface, a height defined between the load contacting surface of the dolly and the ground surface, the plane PPA extending at a distance between 30% and 50% of the height; a swivel platform defining the load contacting surface, the swivel platform extending at an elevation above the frame, the swivel platform mounted on the frame for rotation about a platform axis via a bearing, the platform axis located within the contact footprint; an actuator unit drivingly engaged to at least two rolling elements of the plurality of rolling elements, the at least two rolling elements disposed on opposite sides of the swivel platform; and an on-board controller unit operatively connected to the actuator unit, the on-board controller unit operable to actuate the actuator unit. In accordance with the previous aspects, for example, the plurality of rolling elements are at least partially recessed within the frame. In accordance with the previous aspects, for example, the actuator unit is at least partially recessed within the frame. In accordance with the previous aspects, for example, the bearing is located between a tangential plane passing by a top of the plurality of rolling elements and the plane PPA. In accordance with the previous aspects, for example, the frame extends between a first tangential plane passing by a top of the plurality of rolling elements and a second tangential plane passing by a contact point of the plurality of rolling elements on the ground surface, the tangential planes parallel to each other. In accordance with the previous aspects, for example, the frame is a single block frame, the single block frame defining cut-outs receiving the rolling elements. In accordance with the previous aspects, for example, the height is substantially smaller than a length and/or a width of the dolly. In accordance with the previous aspects, for example, a substantial portion of respective ones of the plurality of rolling elements is contained within the frame. In accordance with the previous aspects, for example, the dolly has a ground clearance underneath thereof, wherein save for the ground clearance, the plurality of rolling elements fully recede within the frame. In accordance with the previous aspects, for example, the plurality of rolling elements have a wheelbase defined between adjacent ones of the plurality of rolling elements on a same side of a meridional plane of the dolly, and a track width defined between respective contact points of opposite ones of the plurality of rolling elements on opposite sides of the meridional plane, a ratio of the wheelbase over the track width is 0.25±0.1. In accordance with the previous aspects, for example, the dolly has a width transverse to a meridional plane of the dolly, a ratio of the track width over the width is 0.9±0.09. In accordance with the previous aspects, for example, the dolly has a length L along the meridional plane, wherein the wheelbase is smaller than 0.3 L±0.1 L. In accordance with the previous aspects, for example, the load contacting surface of the swivel platform extends in a plane PPB above a tangential plane PPT passing by a top of the respective ones of the plurality of rolling elements, wherein an offset between the plane PPB and the tangential plane PPT is at most 25% of the height. In accordance with the previou