Device for a load carrying unit

Device (14) for a load carrying unit (12), intended to interconnect the load carrying unit (12) and a supporting member (10) for the load carrying unit (12), arranged to cause a rotary movement for the load carrying unit (12) in relation to the supporting member (10) in a first plane, and preferably also a pendulous motion in a second plane extending from the first plane. A member (36) is arranged turnable or rotatable in relation to the supporting member (10), suspending the load carrying unit (12), and also a preferably cylindrical disc shaped member (30), defining a first a contact plane directed towards the load carrying unit (12). The load carrying unit (12) is arranged with a contact member, defining a second contact surface directed towards the cylindrical member (30) and extending in a substantially parallel relationship. Two groups of bearing means (44, 46) are arranged in an intermediate position between said first and second contact surface, one group (46) being arranged to take up an adjustable contact against the first contact plane, and a second group (44) being arranged to take up an adjustable contact with the second contact plane.

The present invention relates to a device for a load carrying unit, for 
example excavating machine buckets, wheel tractor buckets, load carrying 
forks for trucks and wheel tractors, and other similar units. 
In existing types of load carrying units, it is often desirable to 
accomplish an improved maneuverability, and for example with regard to 
excavating machine buckets, such improved maneuverability can consist of 
the possibility to cause a rotary movement of the bucket in relation to 
the jib. Also with regard to other types of load carrying units, it is 
desirable to improve the freedom of movement, and for example, fork lift 
trucks utilized for transport of in direction upwards open containers can 
be mentioned, which in a simple manner may be emptied of its contents, 
provided that the supporting lift fork could perform a turning or rotary 
movement. Apart from such a turning or rotary movement, a pendulous motion 
in relation to the rotary plane is also obviously desired, thereby causing 
the material to be removed during an emptying operation to be released in 
a better manner. 
A previously known device for accomplishing a rotary movement of an 
excavating machine bucket in relation to a supporting jib, and also a 
pendulous motion in relation to the rotary plane, is disclosed in SE, A, 
No. 438 882. However, this previously known device facilitates only a 
rather restricted rotary movement, and reduces the capacity of the bucket, 
and the supporting bearing used is rapidly worn down. Previous attempts 
made to attach a bucket to a shaft arranged with cogs, and maneuvered by 
means of a rack, have only resulted in deformation or breakage of the 
supporting shaft, caused by the forces imposed on the shaft during the 
work of the bucket. 
The object of the present invention is to disclose a device facilitating 
maximum movement, both in the rotary plane and during a pendulous motion 
in relation to said plane. A further object is to disclose an improved 
supporting bearing, which can absorb the axial and transverse forces that 
occur, and also being arranged to facilitate adjustment for reduction of 
existing play, e.g. caused by wear. 
The device according to the present invention is intended to belocated in 
an intermediate position between a load carrying unit and a supporting 
member for the load carrying unit, and it is arranged to impose a rotary 
movement for the load carrying unit in relation to the supporting member 
in a first plane, and preferably also a pendulation movement in a second 
plane extending from the first plane, and it is mainly characterised in 
that it includes a tubular or stud shaped member, arranged turnable or 
rotatable in relation to the supporting member, arranged to suspend the 
load carrying unit adjacent to a first end portion, and adjacent to a 
second end portion being joined to a preferably cylindrical and disc 
shaped member, having a surface directed towards the load carrying unit 
defining a first contact plane, the load carrying unit being arranged with 
a contact member, defining a second and towards the cylindrical member 
directed contact plane extending in a substantially parallel relationship, 
two groups of bearing means being arranged in an intermediate position 
between said first and second contact planes, one group being arranged to 
take up an adjustable contact position against the first contact plane, 
and the second group being arranged to take up an adjustable contact 
position against the second contact plane, and with a means being arranged 
to cause a preferably reversible rotary movement of the cylindrical disc 
shaped member, thereby rotating or turning the load carrying unit as 
desired in relation to the supporting member.

With reference to FIG. 1, a jib 10 of an excavating machine and an 
associated bucket 12 are shown in broken lines, the open portion of the 
bucket 12 being directed towards the left side in said figure. The device 
according to the invention, as a complete unit denominated 14, is arranged 
to facilitate attachment against the jib 10 in a conventional manner by 
means of an attachment member 16. The attachment member 16 forms a first 
part of the device 14, and includes two as pairs arranged supporting 
members 18, between which a shaft 20 extends. A second part of the device 
14 comprises of two plate shaped members 22, separated from each other and 
pivotably attached to the shaft 20. The plate shaped members 22 are 
interconnected by means of a plate 24, extending in a transverse 
relationship to the plate shaped members 22. The portion of the second 
part of the device 14 extending from the plate 24 in direction away from 
the supporting shaft 20 is arranged as a housing, intended to protect the 
movable parts included in the device 14. 
A piston cylinder 26, preferably hydraulically operated, is arranged 
extending between a first pivotable attachment point at the attachment 
member 16 and a second pivotable attachment point at the housing arranged 
by the plate shaped members 22, as shown more in detail in FIG. 2. By 
operating said piston cylinder 26, the bucket can be caused to perform a 
pendulous motion, when the second part of the device 14 is moved in 
relation to the first part. 
The device according to the present invention also facilitates a rotary 
movement of the bucket 12, and an example of how such a rotary movement 
can be accomplished is shown in FIGS. 1 and 3. For this purpose a screw 
worm 28 is used, arranged interconnected with a cog wheel 30, having 
peripherially arranged cogs 32 co-operating with the screw worm 28. The 
cog wheel 30 is attached by means of a screw or bolt attachment against a 
first end portion of a stud shaped member 34, the other end portion of 
same being joined to an attachment means 36 for the bucket 12. The stud 
shaped member 34 is arranged rotatable in relation to a surrounding 
tubular member 38, which is rigidly attached to the pivotable second part 
of the device 14. The screw worm 28 is also rotatably supported in this 
second part of the device, driven by means of a motor 40. By influencing 
the motor 40, the screw worm 28 can thus be caused to perform a rotary 
movement, and thereby also rotate the cog wheel 30, the stud shaped member 
34, and the bucket 12. By influencing the rotary speed and the rotary 
direction of the motor 40, the bucket 12 can be rotated in alternate 
directions to any desired angle, and the rotary movement can be performed 
desired number of revolutions in desired direction, and with the rotary 
speed varied as desired. 
In order to absorb the forces and loads imposed during the work of the 
bucket 12, a number of roller shaped members 44, 46 are arranged in an 
intermediate position between a plate 48 at the attachment means 36, and 
the side plane of the cog wheel 30 facing said plate 48. With reference to 
the example of an embodiment shown in FIG. 4, four rollers 44 are utilized 
arranged in contact with the plate 48, and four rollers 46 are arranged in 
contact with the side plane of the cog wheel 30. The number of rollers can 
be varied, but the number of rollers in each contact group should not be 
less than three, whereas there is no objection to use of more than four 
rollers 44, 46 in each group, since an increased number substantially only 
results in advantages. As shown in FIGS. 1 and 4, a tubular bearing is 
also advantageously located intermediately between the stud shaped member 
34 and surrounding tubular member 38, e.g. manufactured from bearing 
bronze, intended to reduce existing friction between the stud shaped 
member 34 and surrounding tubular member 38. 
In order to accomplish favourable and complete contact between the rollers 
44, 46 and associated plate 48 and cog wheel 30 respectively, adjustment 
means 49 are arranged, as shown more in detail in FIG. 2. According to 
this embodiment, the adjustment means 49 comprise of a substantially 
triangular plate, pivotably attached to a wall portion of the second part 
of the device 14, which in this embodiment is arranged as a multisided 
part at the outer portion directed towards the bucket 12, as shown in FIG. 
4. The shafts that support the rollers 44, 46 at the adjustment means 49 
are located slightly displaced in relation to the rotary center for the 
adjustment means 49 at the wall member. As a result, an excentric action 
is achived during a pivoting movement of the adjustment means 49, which 
results in that associated roller 44, 46 is moved against the plate 48, or 
the cog wheel 30. When suitable contact pressure is achieved, the 
adjustment means 49 is locked in the position taken up by insertion of a 
stud in suitable hole 50. The contact pressure is choosen on basis of the 
type of work to be performed. During the work, the rotary movement and the 
pendulous motion of the bucket 12 can be performed independently of each 
other, since the means for accomplishing said movements are individually 
operated. Furthermore, the attachment members 16, 36 facilitate rapid and 
conventional attachment of the device 14 against jibs 10 and buckets 12, 
The device 14 is further extremely compact and requires a minimum of space 
between the bucket 12 and the jib 10. Furthermore, the device 14 does not 
require any space within the bucket 12. The worm gear 28, 30, and the 
rollers 44, 46, are enclosed within a housing and are well protected 
against dirt and damage. Due to the excentric action for collating the 
rollers 44, 46, same are easily adjusted to compensate for existing play, 
and for absorbing and distributing over a large area yhe forces imposed on 
the device 14 during work. The method in which applied forces are 
distributed via the rollers 44, 46 against relatively large pressure 
absorbing surfaces also results in resistance for the device 14 against 
existing forces, as well as extremely good reliability in operation. 
However, the embodiment shown and described can be further modified, either 
in view to make it suitable for other types of machines or load carrying 
units, or with regard to design solutions for included details. As 
examples of such modifications can be mentioned that the rollers 44, 46 
obviously can be suspended in other types of adjustment means 49, which 
have excentric action, e.g. with the shafts of the rollers 44, 46 attached 
in an excentrically located hole arranged in a cylindrical washer member, 
which can be arranged rotatable in a surrounding cylindrical recess. Also 
the method in which the adjustment means 49 is locked in desired position 
can obviously be further varied, and for example lock screws, clamping 
joints and other solutions can be used. For certain applications may also 
the previously discussed pendulous motion be of little interest, in which 
case the members used to accomplish such a motion obviously can be 
excluded. The method in which a rotary movement is accomplished can also 
be further varied, and the motor 40 and the screw worm 28 can for instance 
be replaced by a hydraulically or pneumatically operated piston cylinder, 
attached to a rack interconnected with the cog wheel 30. The rotatable 
stud shaped member 34 can also advantageously be arranged as a tubular 
member, in order to reduce the total weight of the device 14. 
The roller shaped members 44, 46, having a cylindrical cross-section, have 
only small contact areas acting against adjacent contact surfaces. As a 
result, both the roller shaped members 44, 46 and the contact surfaces 
require an extremely hard surface in order to avoid plastical deformation 
caused by existing pressure loads. However, the contact surface of each 
roller shaped member 44, 46 can be considerably enlarged by the 
modification disclosed in FIGS. 5 and 6. 
According to this modified embodiment, each excentrically supported bearing 
means includes a supporting body 44, being located and supported 
correspondingly to the roller shaped members 44, 46 described with 
reference to the embodiment shown in FIGS. 1-4. However, this supporting 
body 44 is arranged with a plane surface 51, in which a groove 52 is 
arranged, extending in a direction corresponding to a through hole 53, 
into which a supporting shaft 54 is insertable. A wear member 55, 
insertable into the groove 52, is also shown, which when inserted is 
arranged having the edge surfaces embraced by the side portions of the 
groove 52. The wear member is attached and held within the groove by means 
of two screws 56, 56, as shown in FIG. 6. 
The supporting body 44 is pivotally supported at an excentric portion 57 of 
the shaft 54, and the outer end portion of the shaft 54 is joined to an 
adjustment means 49, arranged with a number of holes 50, and as previously 
described with regard to the first embodiment, one of these holes is 
utilized to lock the adjustment means in desired position, e.g. by 
inserting a screw 58, stud or similar means. 
This modified bearing means results in an enlarged contact area between the 
bearing means and associated contact surface. The use a wear member 55 is 
advantageous, since same can be replaced when worn, but is is also 
obviously possible to exclude the wear member 55 and associated groove 52, 
and to use a contact surface arranged integrated with the supporting body 
44, i.e. with the plane 51 arranged as a uniterrupted surface. 
The use of a groove 52 in connection with a demountable wear member 55, 
arranged to seize or embrace at least two opposed edge portions of the 
wear member 55, causes the forces applied in use to the wear member 55 to 
be taken up in a better way. However, it is obviously also possible to 
exclude said groove 52, provided that the wear member 55 is attached in 
such a fashion that applied forces are taken up. As an example of such a 
modification can be mentioned the possibility to arrange the wear member 
55 having a width exceeding the width of the supporting body 44, and with 
a groove arranged at the surface intended to abut the supporting body 44, 
whereby the side portions of the groove taken up in the wear member 55 are 
arranged embracing the edge portions of the supporting body 44. 
The present invention is thus in no way restricted to the embodiment shown 
and described, since it can be further modified within the scope of the 
inventive thought and the following claims.