Technical Field
[0001] This disclosure is directed towards a work tool lock extension configured to interlock
with a work tool lock for securing the position of a work tool on a work machine.
Background
[0002] Work machines, such as backhoe loaders, excavators, wheel loaders, bulldozers and
the like, may comprise work tools, such as backhoes and excavators. The work tools
may comprise one or more booms, arms or sticks to which at least one work implement,
such as a bucket, digger and the like, is attached. When the work machine is operational,
the movement of the work tool is typically controlled using a hydraulic system. When
the work machine is not operational, or when the work machine is travelling on a public
road, and the work tool is not being used, the work tool may be locked in a secure
storage position to the main body using a work tool lock. The work tool lock prevents
the work tool from falling out of the desired position under its own weight, which
may happen in the case of a hydraulic fluid leak or other reduction in fluid pressure
in the hydraulic system. The use of a work tool lock is often required under national
regulations when the work machine is travelling on public roads.
[0003] An example of a work tool lock is disclosed in
US-A-2009-0107015. In the apparatus described therein a boom is pivotally attached to the main body
of a work machine. The boom may be secured to the main body using a work tool lock
comprising a lock pin and a lock plate. One of the lock pin and lock plate is attached
to the main body or boom and the other of the lock pin and lock plate is attached
to the other of the main body and boom. The lock plate comprises a hook which may
engage with the lock pin and thereby secure the boom to the main body. The lock plate
is attached to the main body or boom about a pivot and an operation lever is attached
to the lock plate. The operation lever is used to move the lock plate about the pivot,
thereby engaging and disengaging the lock plate from the lock pin.
[0004] In order to improve the stability of the work machine, a work tool will preferably
be locked in a position wherein its centre of mass is as close to the main body of
the work machine as possible. However, if the work tool is pivotally attached to the
main body, this may result in the top of the work tool being raised to a considerable
height from the ground. Different national regulations throughout the world set differing
maximum heights for the top of the work machine and work tool.
[0005] The work tool lock disclosed in
US-A-2009-0107015 enables the boom to be secured in only one position and, therefore, the height of
the top of the boom is fixed. The apparatus does not enable the height to be manually
adjusted to meet differing national regulations. As a result, the size and design
of work machines fitted with such a work tool lock must be adapted for each different
regulatory height requirement.
Summary
[0006] The disclosure provides a work tool lock extension configured to interlock with a
work tool lock for securing a work tool on a work machine, the work tool lock comprising
first and second complementary interlocking means; the work tool lock extension comprising
at least one extension member having first and second engagement means, said first
engagement means being configured to interlock with the second interlocking means
of a work tool lock and said second engagement means being configured to interlock
with the first interlocking means of a work tool lock, such that when inserted into
a work tool lock the extension member separates the first and second interlocking
means.
[0007] The disclosure further provides a work machine comprising:- a work tool lock, said
work tool lock comprising first and second complementary interlocking means; and a
work tool lock extension as provided above; wherein the first engagement means of
the work tool lock extension are configured to interlock with the second interlocking
means and the second engagement means are configured to interlock with the first interlocking
means, such that, when the work tool lock extension is inserted into the work tool
lock, the extension member separates the first and second interlocking means.
[0008] By way of example only, embodiments of a work tool lock extension are now described
with reference to, and as show in, the accompanying drawings.
Brief Description of the Drawings
[0009]
Figure 1 is a side elevation of one type of work machine suitable for the use of the
work tool lock extension of the present disclosure;
Figure 2 is a perspective view of a disengaged work tool lock of the prior art suitable
for interlocking with the work tool lock extension of the present disclosure;
Figure 3 is a perspective view of the work tool lock of Figure 2 when engaged;
Figure 4 is a perspective view of the work tool lock extension of the present disclosure;
Figure 5 is a perspective view of the underside of an extension member of the work
tool lock extension of Figure 4;
Figure 6 is a perspective view of the underside of the extension member of Figure
5 with a support and a side plate hidden from view;
Figure 7 is a perspective view of the work tool lock of Figures 2 and 3 interlocked
with the work tool lock extension of the present disclosure; and
Figure 8 is a perspective view of the arrangement of Figure 7 with a part of a boom,
a side plate and a fastener hidden from view.
Detailed Description
[0010] The present disclosure is directed towards a work tool lock extension for use on
a work machine with a work tool lock for securing the work tool in a storage position.
The work tool lock may comprise first and second interlocking means attached to a
main body of the work machine and/or to a work tool for securing a work tool in a
storage position. The work tool lock extension comprises first and second engaging
means, between which may be located an extension member, for interlocking with the
first and second interlocking means. When the work tool lock extension is interlocked
with the work tool lock, the height of the work tool in the secure storage position
may be reduced in comparison to the height when only the work tool lock is engaged.
[0011] Figure 1 illustrates an exemplary work machine 10 comprising work tools 11, 12 and
a main body 13. In the illustrated embodiment the work machine 10 is a backhoe loader,
the work tool 11 is a loader and the work tool 12 is a backhoe. The work tools 11,
12 may comprise a boom 14, 15, a stick 16, 17 pivotally attached to the respective
boom 14, 15 and a work implement 18, 19, in this example a bucket, pivotally attached
to the respective sticks 16, 17. The boom 15 of the loader may be pivotally mounted
on the main body 13 and the boom 14 of the backhoe may be pivotally mounted on a swing
frame 20 forming part of the main body 13.
[0012] The movement of each of the work tools 11, 12 may be controlled using a hydraulic
or electric system, which may comprise one or more actuators 21, 22, 23, 24, 25 attached
to each of the main body 13, booms 14, 15, sticks 16, 17, work implements 18, 19 and
swing frame 20.
[0013] In the illustrated embodiment, a work tool lock 26 is provided between the boom 14
and swing frame 20 and may be used to secure the work tool 12 in a storage position.
In the case of the backhoe, the storage position is when the boom 14 is held substantially
vertical in an upright position. Alternatively, as is well known, a work tool lock
may be provided between any part of a work tool 11, 12 and any other part of the work
tool 11, 12 or the main body 13 of the work machine 10. For example, a work tool lock
may be provided in between the sticks 16, 17 and the work implements 18, 19.
[0014] Figure 2 illustrates in greater detail the exemplary work tool lock 26, comprising
first interlocking means 27, 28, which may comprise a pair of hook members, pivotally
mounted to the swing frame 20 and second interlocking means 29, 30, which may comprise
a pair of pins, attached to the boom 14. The illustrated work tool lock 26 is commonly
known as a "boom lock". The boom 14 may be attached to the swing frame 20 at a pivot
31, about which the boom 14 is capable of moving relative to the main body 13. To
secure the boom 14 in a storage position, the first interlocking means 27, 28 may
be interlocked with the second interlocking means 29, 30, as illustrated in Figure
3, with the hook members hooked over the pins. The movement of the first interlocking
means 27, 28 may be controlled by a handle 32 and/or by a hydraulic or electrical
actuator 33 attached thereto. In one embodiment the first interlocking means 27, 28
may be mounted on the boom 14 and the second interlocking means 29, 30 may be mounted
on the swing frame 20.
[0015] Figures 4 to 6 illustrate a work tool lock extension 34 of the present disclosure,
comprising a connecting pin 35, an extension member 36 and one or more fasteners 37,
38.
[0016] The connecting pin 35 may be a solid bar with a circular cross section, although
in other embodiments the cross section may be of another shape, such as a square or
triangle. One or more through holes 40, 41, configured for receiving the fasteners
37, 38, may extend through the entire diameter of, and may be located substantially
adjacent to one or both ends of, the connecting pin 35. In embodiments comprising
more than one through holes 40, 41, each may be parallel to another. The illustrated
fasteners 37, 38 are lynch pins, however, the fasteners 37, 38 may be any other type
of suitable mechanical fastener, for example cylindrical rods, nuts and bolts, split
pins, spring pins, R-clips or hitch pins. The through holes 40, 41 and fasteners 37,
38 may form locking means for the connecting pin 35 for securing the connecting pin
35 in the extension member 36.
[0017] The extension member 36 may be comprised of a central plate 42 provided between two
side plates 43, 44, which may be joined together, for example using mechanical fasteners
or by welding, or the central plate 42 and side plates 43, 44 may be formed as a single
part. In Figure 6 the side plate 44 has been omitted, thereby showing the side plate
43 and central plate 42 in more detail. The central plate 42 may be substantially
"T" shaped and may have a width substantially similar to the width of the first interlocking
means 27, 28. A first engagement means 39, for example a hook formed in a part of
the periphery of the central plate 42 not enclosed by the side plates 43, 44, may
be provided in the extension member 36 for interlocking with second interlocking means
29, 30. The two side plates 43, 44 may be identical and may substantially overhang
the edges of opposing sides of the central plate 42, defining a recess 45 therebetween.
A support 46 may be provided between apertures 47, 48 in the free sides of the two
side plates 43, 44 to maintain the shape of the recess 45 if the extension member
36 is knocked or damaged.
[0018] One or more openings 49, 50 may be provided in the extension member 36 adjacent to
the recess 45 and may be configured for the insertion of the connecting pin 35, which,
when inserted into the openings 49, 50, will cross between the side plates 43, 44
through the recess 45. In one embodiment two openings 49, 50 may be provided opposite
one another in each side plate 43, 44. The length of the connecting pin 35 may be
greater than the width of the extension member 36. The one or more through holes 40,
41 may be located such that, when the connecting pin 35 is inserted through the openings
49, 50, the one or more fasteners 37, 38 may be inserted into the one or more through
holes 40, 41 on the outer side of the extension member 36. The fasteners 37, 38 secure
the connecting pin 35 in place by preventing it from sliding out of the openings 49,
50. In one embodiment, one end of the connecting pin 35 may comprise a disc, the disc
having a large diameter than the connecting pin 35, and the other end of the connected
pin 35 may comprise a single through hole for the insertion of a single fastener.
The disc may act as a stop to prevent the connecting pin 35 from sliding out of position.
[0019] The recess 40 and connecting pin 35 may form a second engagement means for engaging
or interlocking with the first interlocking means 27, 28. In one embodiment, wherein
the first interlocking means 27, 28 comprise a hook, the second engagement means are
configured so that the hook may have a close fit with the recess 40 and interlock
with the connecting pin 35.
Industrial Applicability
[0020] The work machine of the present disclosure may a work vehicle and may be of any type,
some examples of which are backhoe loaders, excavators, dozers, track loaders, bulldozers
and wheel loaders. The work tool may comprise one or more booms, sticks, arms and/or
work implements, each of which may be pivotally attached to another part of the work
tool or to a main body of the work machine. The work implements may be of any type,
examples of which include buckets, shovels, grapples, shears, saws, forks, augurs
or material handling arms. The work tool may also be of any type, including, for example,
backhoes, loaders, excavators, material handler front linkages and the like.
[0021] Figure 7 illustrates two work tool lock extensions 34 in use securing a boom 14 in
a storage position. Each of the work tool lock extensions 34 is interlocked with one
of the first interlocking means 27, 28 of the work tool lock 26 and one of the second
interlocking means 29, 30 of the work machine 10. Figure 8 illustrates the same arrangement,
except a side plate 44 and fastener 38 on one of the work tool lock extensions 34
and a part of the boom 14 are not shown.
[0022] The extension member 36 may initially be placed on the first interlocking means 27,
28 by inserting the first interlocking means 27, 28 into the recess 45. The connecting
pin 35 may then be inserted through the openings 49, 50 and secured by the fasteners
37, 38 inserted through the through holes 39, 40. The first interlocking means 27,
28 are thereby interlocked with the second engagement means, and may not be able to
be unlocked unless the connecting pin 35 is removed. The work tool 12 may then be
moved into an upright position and the first engagement means 39 may be interlocked
with the second interlocking means 29, 30 using either the handle 32 or the actuator
33. The first and second interlocking means 27, 28, 29, 30 are thereby separated by
the extension member 36 and the work tool 12 is securely held in a storage position.
[0023] In comparison to the effect of engaging the work tool locks 26 only, the work tool
lock extensions 34 increase the distance between the work tool 12 and the main body
13 of the work machine 10 when the work tool 12 is in the sstorage position. As a
result, the height of the top of the work tool 12 is lower. Identically designed work
machines 10 may therefore be designed regardless of differing national height regulations.
Different sized work tool lock extensions 34 may be provided to adapt the height of
the work tool 10 to suit the differing height regulations. This may enable the work
machine 10 to be driven on roads anywhere in the world with the work tool 10 secured
in the storage position.
[0024] When the work tool 12 is not secured in the storage position, or there is no requirement
to reduce the height of the work tool 12, the work tool lock extensions 34 may be
removed and stored for later use.
1. A work tool lock extension (34) configured to interlock with a work tool lock (26)
for securing a work tool (11, 12) on a work machine (10), the work tool lock (26)
comprising first and second complementary interlocking means (27, 28, 29, 30);
the work tool lock extension (34) comprising at least one extension member (36) having
first and second engagement means (39), said first engagement means (39) being configured
to interlock with the second interlocking means (29, 30) of a work tool lock (26)
and said second engagement means being configured to interlock with the first interlocking
means (27, 28) of a work tool lock (26), such that when inserted into a work tool
lock (26) the extension member (36) separates the first and second interlocking means
(27, 28, 29, 30).
2. A work tool lock extension (34) as claimed in claim 1 wherein the first engagement
means (39) comprises at least one hook and the second engagement means comprises at
least one removable pin (35).
3. A work tool lock extension (34) as claimed in claim 1 or claim 2 in which the at least
one extension member (36) defines a recess (45) configured for receiving the second
interlocking means (29, 30) of a work tool lock (26).
4. A work tool lock extension (34) as claimed in claim 3 wherein the extension member
(36) comprises a central plate (42) partially located between two side plates (43,
44) with the recess (45) extending between the two side plates (43, 44).
5. A work tool lock extension (34) as claimed in claim 3 or claim 4 wherein the pin (35),
when inserted in the extension member (36), extends across the inside of the recess
(45).
6. A work tool lock extension (34) as claimed in any one of claims 2 to 5 wherein the
extension member (36) comprises at least one opening (49, 50) extending through the
extension member (36) for receiving the pin (35).
7. A work tool lock extension (34) as claimed in any one of claims 2 to 6 in which the
pin (35) further comprises locking means for securing the pin (35) in the extension
member (36).
8. A work tool lock extension (34) as claimed in any one of claim 2 to 7 wherein the
at least one hook is formed in the central plate (42).
9. A work machine (10) comprising:-
a work tool lock (26), said work tool lock (26) comprising first and second complementary
interlocking means (27, 28, 29, 30); and
a work tool lock extension (34) as claimed in any one of the preceding claims;
wherein the first engagement means (39) of the work tool lock extension (34) are configured
to interlock with the second interlocking means (29, 30) and the second engagement
means are configured to interlock with the first interlocking means (27, 28), such
that, when the work tool lock extension (34) is inserted into the work tool lock (26),
the extension member (36) separates the first and second interlocking means (27, 28,
29, 30).
10. A work machine (10) as claimed in claim 9 wherein the first interlocking means (27,
28) comprises at least one hook and the second interlocking means comprises at least
one pin (35).
11. A work machine (10) as claimed in claim 9 or claim 10 wherein the work machine (10)
is a backhoe loader.
12. A work machine (10) as claimed in claim 11 further comprising a work tool (11, 12)
wherein the work tool (11, 12) is a backhoe mounted on a swing frame (20) and the
work tool lock (26) is for securing the backhoe to the swing frame (20).