Loading vehicle for picking up and transporting straw material

A loading vehicle having a pick-up drum with resilient fingers for picking up straw material from the ground and a conveyor drum with conveyor arms, fitted in rows for carrying the material into the vehicle. The pick-up drum and the conveyor drum are disposed with respect to each other so that the conveying direction of the material is abruptly changed when the material is introduced into the path of motion of the conveyors. This produces a damming-up effect causing the material to be distributed over the entire conveyor front, which minimizes the tendency of squeezing between conveyors and the housing wall defining the conveyor duct at one side. The change in conveying direction also causes a certain compaction of the material, resulting in a better utilization of the available volume. The structure allows short spacing between the conveyor arms and closely spaced knives are positioned in the conveyor duct so that the blades of straw can be cut in small pieces which are suitable for ensilage.

The invention relates to a loading vehicle for picking up and transporting 
straw material, comprising a rotary pick-up drum which is fitted at the 
front and has resilient pick-up fingers passing the straw material up to a 
rotary conveyor drum whose conveyors, fitted in rows, convey it up into 
the body of the vehicle through a duct, which at one side is defined by 
the drum and by strippers between which the conveyors pass. Such loading 
vehicles were originally developed for gathering in grass and hay in full 
length and are widely used, particularly on a difficult ground. To make 
them useful also for picking up grass for ensilage they were later 
provided with stationary knives in the conveyor duct for chopping the 
blades of grass. 
In the known loading vehicles of the present type it is endeavored to 
establish a path of movement for the straw material which is as even and 
has as few obstacles as possible by an arrangement in which the pick-up 
drum, which is mounted at the front, conveys the material up to the lower, 
substantially horizontal part of the upwardly inclined lower wall of the 
duct, and then the further transport is ensured by the conveyors of the 
overhead conveyor drum whose outer ends in this region of the duct sweep 
closely past the lower wall of the duct, the conveyor drum rotating in the 
opposite direction of the pick-up drum. In this construction the straw 
material may be squeezed between the conveyors and the bottom of the duct. 
Where chopping is desired with a view to ensilage, chopping knives are 
fitted in the duct which extend up through the bottom of the duct so that 
the conveyors may pass between them. The squeezing tendency sets a limit 
to how closely spaced the conveyors in each row can be positioned, which 
makes it impossible to obtain such a short chopped length as is necessary 
to meet the requirements made today of good ensilage. 
The object of the invention is to provide such an embodiment of a loading 
vehicle of the present type as eliminates or at any rate minimizes the 
squeezing tendency and consequent restrictions. 
This object is achieved in that the pick-up drum is placed with respect to 
the conveyor drum so that the conveying direction of the straw material is 
abruptly changed at the inlet to the conveyor drum; the abrupt change in 
the conveying direction of the straw material, which takes place when the 
material encounters a set of conveyors, provides partly a damming-up 
effect causing the material to be distributed over the entire conveyor 
front or at any rate a great part of it, partly a certain compaction of 
the material which increases the capacity of the transport mechanism and 
results in a better utilization of the capacity of the vehicle. 
The minimized squeezing tendency allows the use of closely spaced 
conveyors, and the spaces between the conveyors in each row can 
expediently be less than 30 mm. 
It is particularly expedient to mount the pick-up drum below and behind the 
conveyor drum so that the pick-up drum can pivot upwards and rearwards, 
because it can then swing clear of obstacles and the distance between the 
hauling tractor and the loading vehicle can be reduced to greater degree 
than is feasible with the conventional loading vehicles. 
When a knife is fitted at the inlet to the conveyor drum, said knife 
extending in the entire length of the drum and having a cutting edge which 
faces in the opposite direction of the one in which the conveyors pass the 
knife, at least a part of the straw material will be cut when the 
conveyors transport it past the knife. 
A conveyor structure with closely spaced conveyors enables the transport 
mechanism to press the material up into the vehicle against a greater 
counterpressure than the one caused by the weight of overlying material in 
a completely filled vehicle. This circumstance makes it possible to avoid 
the use of complicated transport chains requiring much maintenance. 
Various simple and sturdy mechanisms for guiding the supplied material 
rearwardly in the vehicle are defined hereinafter.

The loading vehicle shown in FIG. 1 has a box-shaped body 10 comprising a 
bottom 11 resting on a bogie 12 with two pairs of wheels 13, side walls 
14, a front wall 15 and a rear wall 16. The front end of the vehicle 
mounts a pull rod 17 by means of which the vehicle may be coupled to a 
tractor. At 20 is indicated a transmission means for transmitting drive 
force from the tractor to the driven elements of the loading vehicle. A 
pick-up and transport mechanism, which is seen best in FIG. 2, is mounted 
below the front end of the vehicle and comprises a pick-up 18 and a 
conveyor assembly 19. 
The pick-up 18 has a drum 21 which extends in the entire width of the 
vehicle and is rotatably journalled in a housing 22. Four rows of 
resilient pick-up fingers 23 are peripherally spaced on the drum, and when 
the drum is rotated in the direction shown by an arrow 24 the fingers 23 
sweep across the surface of the ground and lift and convey straw material 
disposed on the ground. The fingers 23 are controlled in a conventional, 
not shown manner so that they extend radially out through slits in the 
housing 22 during the active portion of their motion, but are pivoted 
rearwards from the radial position at the upper portion of their path of 
motion where they approach the conveyor assembly 19 so that they will not 
hit this assembly. 
The conveyor assembly 19 is mounted above and ahead of the pick-up 18 so as 
to pick-up the straw material lifted by the pick-up and to convey it up 
into the body of the vehicle. This assembly has a drum 26 which is 
rotatably mounted in a housing 25, said drum 26 extending in the entire 
width of the vehicle and carrying a plurality of peripherally spaced rows 
of radial conveyor arms 27. Four rows of conveyors are shown in the 
drawing. The drum 26 is driven in the direction shown by an arrow 28. The 
rows of conveyors may be disposed in axial planes; but they may also be 
positioned along helical lines on the drum surface, which provides for a 
more even distribution of the load. 
The upper portion of the conveyor assembly 19 extends up through an opening 
at the front portion of the bottom of the vehicle, which is indicated by a 
frame box beam 29 in FIG. 2. The lower portion 30 of the conveyor housing 
25, defining together with the pick-up housing 22 an inlet opening 31, is 
provided with a softly rounded edge portion. A plurality of strippers 32 
are secured to a carrier beam 33 inside the vehicle, from which they 
extend obliquely forwards and downwards toward the drum surface to prevent 
the straw material from following the conveyor drum all the way around. 
The strippers 32 are positioned opposite the spaces between the conveyors 
27 and have a width which allows the conveyors to pass unobstructedly. The 
front portion of the housing 25 defines together with the drum 26 and the 
strippers 32 a conveyor duct 34. 
In the embodiment shown, the conveyor duct 34 has mounted in it a set of 
chopping knives 35, which are disposed opposite their respective spaces 
between the conveyors 27 and extend from a knife holder beam 36, provided 
exteriorly of the housing 25, inwards toward the conveyor drum 26 through 
slits 37 in the housing. Each individual knife is pivotable in its own 
plane about a hinge 38 formed by the engagement of two hook-like members 
on the knife and the beam, respectively. Each knife 35 has a pressure 
spring 39 which, through a toggle mechanism 40, affects the knife 
resiliently to assume its operating position which is shown in full lines 
and is determined by the abutment of the toggle on a stop means 41. If a 
hard object, such as a stone, is conveyed together with the straw up into 
the duct 34, the spring 39 will yield and allow the knife 35 to pivot to 
the position shown in dashed lines. The knife assembly may also be 
arranged so that all the knives or groups of knives pivot at the same 
time. The knives chop the straw with a view to subsequent ensilage. 
Straw material lying on the ground, as seen in relation to the loading 
vehicle, is introduced into the vehicle in the direction shown by an arrow 
42. Immediately after being passed through the inlet opening 31 by the 
pick-up fingers 23, the material is gripped by a set of conveyors 27 
conveying it in largely the opposite direction of the inlet direction, as 
indicated by arrows 43 and 44. This abrupt change in the direction of 
movement produces a damming-up effect, causing the straw material to be 
radially distributed over the entire conveyor front instead of 
accumulating, as is often the case in conventional structures, at the 
extremities of the conveyors, which results in a squeezing tendency 
between the conveyors and the housing. Further, the change in the 
direction of movement causes the material to be compacted more than it 
would otherwise be, resulting in a better utilization of the volume of the 
conveyor duct as well as of the body. 
Having being pressed over the stripper beam 33 by the conveyors, the 
chopped straw material slides down a platform 45 to an intermittently 
operating conveyor belt 46, which is mounted on the bottom of the vehicle 
and transports the material stepwise rearwardly in the vehicle in a 
generally known manner. 
The embodiment shown in FIG. 3 of the pick-up and transport mechanism 
differs from that of FIG. 2 in that in the edge portion 30a of the 
conveyor housing 25a defining the inlet opening 31a there is mounted an 
additional knife 35a, which extends in the entire length of the opening 
and whose cutting edge faces towards the opening and in an opposite 
direction of the one in which the conveyors 27a pass the opening. The 
cutting edge of the knife 35a may be straight or serrated, and the knife 
contributes to the chopping of the material fed. In the structure of FIG. 
3 the lower portion of the conveyor housing also has a guard plate 30b 
extending forwardly from the knife 35a and screening the movable knife 
asembly from the ground. 
The reduced squeezing tendency in the structure described in the foregoing 
allows the conveyors to be disposed closely spaced, which in turn permits 
a short chopped length and enables the conveyors to transport the material 
up into the vehicle against a great counterpressure. Thus, it has been 
found that the conveyors can without difficulty press straw material into 
a completely filled vehicle. 
FIG. 4 schematically shows a two-wheel loading vehicle in which the lifting 
capacity of the conveyors is utilized for simplifying the means employed 
to carry the material rearwardly in the vehicle from the mouth of the 
conveyor duct. Thus, these means just comprise a rapidly rotating peg drum 
47 fitted at the top in the vehicle just above the conveyor duct. As the 
material reaches the level of the peg drum, this drum throws it rearwards 
with such a great force that also the rear end of the vehicle will be 
completely filled. Unloading can take place by tipping the body as shown 
by the dashed lines. 
The loading vehicle shown in FIG. 5 has a scraper 48 which when being moved 
to and fro in horizontal grooves (not shown) along the upper edges of the 
sides of the vehicle directs the material rearwardly as it reaches above 
the lower edge of the scraper. The scraper must be suspended, in a known, 
not shown manner, so that it is kept substantially vertical during its 
rearward movement, but can pivot freely rearwards about an axis along its 
upper edge during its forward movement. The movement of the scraper can, 
e.g. as shown, be produced by a pair of drive arms 49 which are pivotally 
journalled at the bottom of the vehicle and connect the scraper to 
pin/slit connections (not shown). The drive arms can be pivoted to and fro 
by a hydraulic cylinder (not shown). 
The loading vehicle shown in FIG. 6 has a curved guide plate 50 whose front 
edge at 51 is hinged to the upper edge of the front wall of the vehicle, 
from which the guide plate extends rearwards. The lateral edges of the 
guide plate mount two substantially triangular side plates 52 which extend 
downwards along the outer surface of the sides of the vehicle in the 
unaffected position of the guide plate, shown in FIG. 6. The guide plate 
and the side plates are made of a light-weight material, such as plastics. 
When the fed material reaches the underside of the guide plate 50, it 
lifts this plate and follows its curved underside and is thus guided 
rearwards in the vehicle. 
FIG. 7 shows a substantially truncated container or body which is 
particularly useful on a difficult ground. The container may be arranged 
to be carried by a tractor or may be provided with wheels like the other 
ones shown. 
The base 53 of the container has a steep rearward and downward inclination 
from the mouth of the conveyor duct to the rear wall 54 of the container 
hinged at its upper edge so that unloading may be effected by pivoting the 
rear wall backwards as shown by a dashed line. 
The loading vehicle of the invention can be modified in many other ways 
than those shown and described in the foregoing. For example, the pick-up 
18 might be fitted ahead of the conveyor assembly 19, as it used to be.