Methods of moving at least one mat with a crane-mounted grab head

Patent metadata

Field	Value
Publication number	US-9297124-B2
Application number	US-201514852589-A
Country	US
Kind code	B2
Filing date	Sep 13, 2015
Priority date	Feb 18, 2013
Publication date	Mar 29, 2016
Grant date	Mar 29, 2016

Abstract

Method of handling at least one mat with the use of a crane-mounted grab head includes extending the first tooth of a first jaw of the grab head at least partially through a first hole in the mat and the first tooth of a second jaw of the grab head at least partially through a second hole in the mat. At least one actuator moves the jaws toward one another. The grab head is raised to lift the first mat. The mat is positioned at the desired location and the grab head is disengaged from the mat.

First claim

The invention claimed is:

1. Method of handling at least one mat with the use of a crane-mounted grab head, each mat being configured to withstand the load of a vehicle passing over it, each mat having at least first and second spaced-apart holes extending therethrough and at least first and second peripheral sides opposite one another, each mat further having a stepped-configuration that includes a first projection extending at least partially along at least the first side of each mat and a second projection extending at least partially along at least the second side of each mat, the first and second projections being offset height-wise relative to one another so that the first projection is lower than the second projection when each mat is upright, wherein at least the first hole is formed in the first projection and at least the second hole is formed in the second projection, the grab head including a central portion engageable with the crane, at least first and second elongated telescoping supports extending linearly from and in opposite lateral directions relative to the central portion, each of the first and second supports having a central longitudinal axis, a first jaw disposed proximate to the end of the first support opposite the central portion and a second jaw disposed proximate to the end of the second support opposite the central portion, and at least one actuator configured to selectively and independently move each of the first and second jaws toward and away from one another, each jaw including at least a first tooth extending downwardly therefrom, each tooth of each jaw having at least one flange projecting in the direction of the other jaw, the first tooth of the first jaw being engageable with the first hole in each mat and, concurrently, the first tooth of the second jaw being engageable with the second hole in each mat, wherein when the central longitudinal axis of the first and second supports is oriented generally horizontally, the flange of each tooth of the first jaw is configured to be positioned farther downwardly relative to the central portion of the grab head than the flange of each tooth of the second jaw, the method comprising:
(a) the crane extending the first tooth of the first jaw of the grab head at least partially through the first hole in a first mat and the first tooth of the second jaw of the grab head at least partially through the second hole in the first mat;
(b) at least one actuator of the grab head moving the first and second jaws toward one another sufficient to position each flange of each respective tooth at least partially below the first mat adjacent to the corresponding associated hole of the first mat;
(c) the crane raising the grab head to lift the first mat;
(d) the crane placing the first mat at a desired location;
(e) at least one actuator of the grab head moving the first and second jaws away from one another to align each flange of each respective tooth in or below the corresponding associated hole of the first mat; and
(f) the crane lifting the grab head away from the first mat.

2. The method of claim 1 further including
(g) the crane placing the first mat at a desired location on the ground.

3. The method of claim 2 further including
(h) repeating steps (a)-(f) with respect to a second mat,
(i) the crane placing the second mat at a desired location on the ground proximate to the first mat, and
(j) interconnecting the first and second mats to form a temporary surface.

4. The method of claim 3 further including
(k) repeating steps (a)-(f) with respect to multiple subsequent mats,
(l) the crane placing each subsequent mat at a desired location on the ground proximate to at least one other mat, and
(j) interconnecting the mats to form a temporary surface.

5. The method of claim 1 wherein when the first mat and a second mat are positioned adjacent to one another on the ground, further including
the crane engaging the first tooth of the first jaw with a hole formed in the first mat and the first tooth of the second jaw with a hole formed in the second mat, and
at least one actuator of the grab head moving the first and second jaws away from one another with sufficient force to push at least one among the first and second mats away from the other.

6. Method of displacing at least one among first and second mats positioned adjacent to one another on the ground from the other such mat with the use of a crane-mounted grab head, each mat being configured to withstand the load of a vehicle passing over it, each mat having at least first and second spaced-apart holes extending therethrough, the grab head including a central portion engageable with the crane, at least first and second elongated telescoping supports extending linearly from and in opposite lateral directions relative to the central portion, a first jaw disposed proximate to the end of the first support opposite the central portion and a second jaw disposed proximate to the end of the second support opposite the central portion, each jaw including at least first and second spaced-apart teeth extending downwardly therefrom, each tooth of each jaw having at least one flange projecting in the direction of the other jaw, and at least one actuator configured to selectively and independently move each of the first and second jaws toward and away from one another with equal force, the method comprising:
the crane extending each tooth of the first jaw of the grab head at least partially through the first and second holes in the first mat;
the crane extending each tooth of the second jaw of the grab head at least partially through the first and second holes in the second mat;
at least one actuator moving the first and second jaws away from one another with sufficient force to push at least one among the first and second mats away from the other; and
the crane lifting the grab head away from the first and second mats.

7. The method of claim 6 further including at least one actuator moving the first and second jaws toward one another to position each flange of each respective tooth in or below the corresponding associated hole in the first or second mat.

Assignees

• Terra Roadways Ltd Fa
• Newpark Mats & Integrated Services Llc

Inventors

• Robertson Hugh Stewart

Classifications

• B66C13/46

  Position indicators for suspended loads or for crane elements · CPC title

• E01C9/08

  Temporary pavings ({E01C9/008 takes precedence } ; steel gratings E01C9/10) · CPC title

• B66C1/66 Primary

  for engaging holes, recesses, or abutments on articles specially provided for facilitating handling thereof · CPC title

• E01C19/52 Primary

  Apparatus for laying individual preformed surfacing elements, e.g. kerbstones · CPC title

• B66C1/44

  and applying frictional forces · CPC title