A Spreader equipment for liquid manure, e.g. a semi-liquid slurry
The present invention relates to a spreader equipment for liquid manure, e.g. a semi-liquid slurry, comprising at least one injection nozzle which is, via a pipe, connected with a supply valve for periodical supply of a semi-liquid slurry under pressure from a container of semi-liquid slurry for direct injection of semi-liquid slurry into the soil, which spreader equipment is preferably provided on a vehicle for movement on the surface of the ground, as stated in the introductory part of the following independent claim.
All recent focusing on environmental problems burdening agricultural trade, caused experiments to be made in order to develop machinery and equipment which may reduce/eliminate such problems. One of the most heavy environmental problems seems to be farmyard manure. When farmyard manure is sprea onto the soil without being mixed with the soil, a larg portion of the nutrients (especially nitrogen) will b subject to loss (gaseous ammonia to the atmosphere). Also, the manure will liberate unpleasant odorous matter, and ther will be drainage to runoff and water systems, especially whe there is rain for some considerable time.
In order to remedy the above disadvantages experiments wer made and equipment was produced for introduction of liqui manure into the soil, as mentioned above.
By introducing liquid manure, e.g. a semi-liquid slurry under pressure by the aid of an injection nozzle forming concentrated directed jet, the soil may partly be broken u and plant growth may be disturbed.
It is an object of the present invention to provide spreader equipment of the kind as mentioned above, by the ai
of which the introduction of liquid manure into the soil will occur in a gentle manner as regards the soil and any growing plants, and with high efficiency. According to the invention this is achieved by the aid of the features which are stated in the characterizing part of the following independent claim 1 as well as in the following dependent claims. By the aid of the invention gentle and efficient introduction of liquid manure, especially a semi-liquid slurry, into the soil is achieved, with considerably reduced liberation of nitrogen to the atmosphere and liberation of odorous matter, and with the liquid manure being to a high degree advanced directly to the root system of plants, and with considerably reduced runoff from a sloping ground.
The spreader equipment according to the invention is disclosed in more detail below with reference to the drawings, which show an embodiment of the invention and in which:
Figure 1 is an elevational view of the spreader equipment which is mounted on a vehicle; Figure 2 shows the spreader equipment in a rear view; Figure 3 is a sectional view of the injection nozzle of the spreader equipment, and a supply valve for liquid manure with a stator and a cyindrical rotor chamber.
Figure 1, thus, shows spreader equipment for liquid manure, e. g. a semi-liquid slurry, comprising at least one injection nozzle 1 which is connected with a supply valve 6 for periodical supply of semi-liquid slurry under pressure from a tank 4 for semi-liquid slurry, for direct injection of semi- liquid slurry into the soil. The spreader equipment is preferably mounted on a vehicle H for movement on the surface of the ground E.
Injection nozzle 1 is provided at end 3a of an arm 3, whic is mounted to be slewable about a horizontal axis on carrier means 11, which is secured to vehicle E. Arm 3 i connected with a pressure cylinder 10, which is to exert desired constant flexible pressure against the arm to urg injection nozzle 1 into resilient contact with surface of th ground E.
Injection nozzle 1 is slewably mounted on arm 3 by the aid o a spherical bearing lg so as to be able to adapt to rough nesses of the surface of the ground E.
Injection nozzle 1 is, thus, arranged to be in resilien contact with ground surface E with a lower portion, and i comprises a valve housing la with an inlet la' and a outwards diverging and downwards facing outlet passage 11. valve member lc, which is displaceable axially outward against a spring means If, is provided in outlet passage l and is spring loaded inwards into sealing cooperation wit defining surface 11' of outlet passage li. Displacement o valve member lc will cause a passage C to be formed with a annular nozzle opening Cl between valve member, lc an defining surface 11'. Valve member lc will, thus, be urge down by pressure exerted by the semi-liquid manure, fo periodical opening of nozzle opening C and, consequently injection of the semi-liquid slurry into the soil. Inlet la of valve member la is connected with outlet 6e of suppl valve 6, via a pipe 2, and its inlet 6d is furthermor connected with a pressure pump P and tank 4 for semi-liqui manure by the aid of a pipe 5.
The lower portion 12 of injection nozzle 1, which forms th surface of valve housing la facing downwards towards groun surface E, is designed to be a saucer shaped body 12a with central opening 12b, into which outlet passage li of th injection nozzle opens, as shown in Figure 3. In this manne a sliding surface 12 with upwards curved lateral edges i
achieved, causing the injection nozzle 1 to slide readily. on the soil in all directions, which is important when driving in a curve, in which case there is a combination of forward motion and transversal motion of the injection nozzle 1 on the ground.
Due to the fact that valve member lc is in sealing engagement with defining surface 11' of the outlet passage li in between periodical ejections of the semi-liquid slurry, the valve member will prevent particles from penetrating into the annular nozzle opening C which is then closed.
As will appear from Figure 3, both outlet passage li and valve member lc are cone shaped with different cone angles , β, so that the width of annular passage C is reduced in the direction of nozzle opening C. The periodical pressure of semi-liquid slurry on the cone shaped plate of valve member lc will, thus, urge the valve member down against the above mentioned spring force to open nozzle opening C.
As shown in Figure 3, valve member lc has a valve spindle lb extending upwards in valve casing la through lower and upper guiding and supporting bearings Id, le, which are arranged in said casing in the shape of bearing sleeves. Valve spindle lb, the top portion of which projects outside valve casing la, is provided with an adjustable stop If for cooperation with a compression spring If", which is supported by the outside of valve casing la.
The above mentioned supply valve is shown in its mounted position in the spreader equipment in Figures 1 and 2, and it is shown in cross section and in a larger scale in Figure 4. Supply valve 6 comprises a stator 6a with a cylindrical rotor chamber 6a' comprising an inlet 6d from tank 4 for semi- liquid slurry, via pressure pump P, and an outlet 6e, which is connected with injection nozzle 1 by a pipe 2. An adjustably driven supply rotor 6b is provided in said cylindrical rotor chamber 6a' and comprises a supply chamber
6c, which connects inlet 6d and outlet 6e in a certain angular region of rotation of rotor 6b relative to stator 6a so that semi-liquid slurry under pressure may pass to and through hose 2 to injection nozzle 1.
Inlet 6d and outlet 6e are provided in the end wall of rotor chamber 6a', and in its cylindrical mantle wall, respective¬ ly, within the same angular sector of rotor chamber 6a', and with their centres preferably in the same radial plane to the axis of rotation of rotor 6a'. A pre-filler pipe connection 6f which is connected with the pressure side of pressure pump P, via a hose 8, and a return/ventilation pipe connection 6g, which is connected with tank 4 for semi-liquid slurry, via a pipe 7, are provided in the end wall, and mantle wall, respectively, of rotor chamber 6a' within the same angular sector in rotor chamber 6a' in front of the angular sector of inlet and outlet 6d, 6e, as seen in the direction of rotation A of rotor 6b. Return/ventilation pipe connection 6g is provided in the end wall of rotor chamber 6a' and in front o the pre-filler pipe connection 6f in the mantle wall.
In an angular sector behind the angular sector of inlet an outlet 6d, 6e, as seen in the direction of rotation A o rotor 6b, a drainage pipe connection 6h is arranged t provide for outlet of liquid that might be squeezed i between rotor 6b and the wall of rotor chamber 6a' , and i desired, to provide for outlet of residual semi-liquid slurr under pressure which might be present in supply chamber 6 when the latter is made to pass drainage pipe connection 6 during rotation of rotor 6b. During further rotation of roto 6b supply chamber 6c is advanced to pre-filler pipe connect ion 6f and return/ventilation pipe connection 6g, wher supply chamber 6c is filled with semi-liquid slurry, possibl during simultaneous removal of air through said return/vent ilation pipe connection 6g. During further rotation of th rotor supply chamber 6c is advanced to inlet 6d and outle 6e. Semi-liquid slurry under pressure flows in through inle
6d and urges semi-liquid slurry which is already present In supply chamber 6c out through outlet 6e, via pipe/hose 2 to injection nozzle 1.
As shown in Figure 4, rotor 6b comprises two supply chambers 6c which are mutually opposed in a radial direction. Consequently, supply of semi-liquid slurry to injection nozzle 1 occurs twice in the course of one revolution of rotor 6b.
As will appear from Figures 1 and 2, arm 3 is rotatably mounted on the outside of stator 6a which is cylindrical and forms the bearing shaft. In this manner a compact design of the spreader equipment is achieved, with the latter being secured to vehicle H by its carrier arm 11.
Supply valve 6 may be extended in its axial direction thus to constitute a common supply valve for several injection nozzles 1, which are provided on arms 3 comprising a pressure cylinder 10 each. Arms 3 are in this case mounted side by side and at a mutual distance on stator 6a to be independent¬ ly rotatable.
The spreader equipment according to the invention is especially intended for direct injection of semi-liquid slurry into the soil with the least possible damage to the surface, and it is especially useful for spreading and introducing semi-liquid slurry on grassland without damaging the turf.
By adjusting the rpm of rotor 6b of supply valve 6 and the pressure of pressure pump P the volume of semi-liquid manure supplied during an injection period may be varied within wide limits. The driving pressure of pump P may, e.g. be between 2 and 20 bar absolute.