FR2683699A1 - DRIVE ASSEMBLY FOR A CENTRIFUGAL SPREADER. - Google Patents

Abstract

Drive assembly for a centrifugal spreader having at least two spreading discs (8) very distant from each other, comprising a transmission member (10) housed in a closed housing (24), consisting of a central bevel gear mechanism (11), the input shaft of which can be coupled to the PTO of a tractor and end return mechanisms (12, 13) arranged on either side of the central mechanism (11) and connected to it by a transverse shaft (20), on the output shaft (16, 17) of each of which is mounted a spreading disc (8). Provision is made for the housing (24) of the transmission member (10) using a standard commercial tube and to center and mount the bearings (21, 22, 23, 30, 31, 34) of the shafts (14, 16, 17, 20) on surfaces machined on the outer face of the tube, the tube being closed on its two end faces by covers (40, 41).

Description

1 2683699

  Drive assembly for a centrifugal spreader The invention relates to a drive assembly for a centrifugal spreader of granular products liable to flow, having at least two spreading discs arranged very far apart

  each other, consisting of a trans-

  mission housed in a casing having a central gear mechanism whose input shaft can be coupled to the power take-off of a tractor and, arranged on each side of the central gear mechanism and connected to it by a transverse shaft, angle gear end mechanisms, a spreading disc being mounted on the output shaft of each of them, these output shafts being arranged substantially perpendicular to the input shaft, all the transmission organ shafts

  being mounted on bearings in the housing.

  With the aim of making the spreading operation, in particular the spreading of fertilizers in agriculture, as efficient as possible, reservoirs for large-scale spreading product are used on the one hand, in order to be able to treat the larger surface possible with a load, and on the other hand, we are looking for large spreading widths, which in turn require a large amount of product to

spread according to the route.

  These requirements have led to the

  product application tanks have a door to

  lateral false reaching the maximum width authorized for road traffic, and that the spreading discs are very distant from each other, in particular to be able to cause the product to spread, by the sole force of gravity, the along the inclined walls of the tank to the outlet openings

of it.

  The fact that the spreading discs are very far from each other is the cause of specific drive problems There are certainly individual hydraulic drives for the two spreading discs, but such drives are very costly and require numerous speed settings Similarly, the operational safety of these drives, in particular those of hydraulic drive systems, is easily reduced

  by difficult operating conditions.

  The maintenance required is also important.

  This is why current and inexpensive drives operate with gear transmissions, comprising a central bevel gear mechanism, to the input shaft of which the PTO is connected Via a transverse shaft on which is mounted the output pinion of the bevel gear mechanism, the torque is transmitted to two angle gear mechanisms, on the output shafts of which are mounted the spreading discs These transmission members, commonly used on centrifugal spreaders , can, over a length outside

  all low, be made easily and at low cost.

  As a rule, they have a rectangular cast iron casing in which the gear mechanisms and their bearings are mounted, as well as the support bearings for the transverse shaft (US-PS no 2

044).

  In the case of a longer overall length, the casing must be produced in several parts, in order to be able to carry out inside the machining necessary for fixing and centering the bearings. This increases the cost of the transmission and its weight, which is a drawback for using the tractor from the point of view of a maximum payload (quantity of product to be spread). In addition, a significant overall length of

3 2683699

  the transmission member and the simplicity desired at the mounting level necessarily generate larger manufacturing tolerances which can cause misalignments at the level of the transverse shaft and, therefore, the offset of the transmission members. We have tried to remedy these difficulties (DE-OS n ° 3 819 794) by conforming the central gear mechanism and the two angle gear end mechanisms into individual shielded mechanisms and by fixing them to the cross member of the frame of the centrifugal spreader L the transverse shaft has been divided into several parts, while providing on both sides of the central gear mechanism flexible sections which are liable to undergo twists to compensate for the tolerances resulting from measurement errors, welding deformations, etc. on the cross member In this case, an additional covering must be provided in the form of a casing for the rotary parts of the transverse shaft. ns, this achievement is

  also demanding and expensive construction.

  The object of the invention is to propose a traditional mechanical transmission assembly for a centrifugal spreader with two spreading discs very distant from each other, which can be constructed at

  low cost for a reduced construction mass.

  This object is achieved by the invention in that the casing of the transmission member is produced from a usual commercial tube -a rectangular section and in that the bearings of the shafts are centered and rest on machined surfaces of the outer face of the tube and in that the tube is closed

  on its two front faces by covers.

  In the embodiment of the invention, a section tube is used for the housing.

  commercially available rectangular and therefore inexpensive.

  With such rectangular section tubes, installing and centering the bearings inside would cause

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  considerable cost of finishing, because it would be necessary to drill access holes with a sufficiently large internal diameter which would have to be closed at least on one side Likewise, mounting inside would be made considerably difficult due to the small internal section and the great constructive length The invention makes it possible to solve these difficulties in that the bearings of the shafts are mounted in abutment and centered on machined surfaces of the outside face of the tube with rectangular section, thus making it possible without problem and in a simple way. execution of the work using standard tools, without weakening the casing by transverse holes, or requiring the installation of additional walls for closing the holes. Due to greater finishing tolerances on long tubes, which can for example reveal themselves by defects in parallelism of the walls, warping in length, etc., the fact that the invention provides exclusively external machining gives a simple possibility of satisfying these tolerance requirements The bearings are thus either mounted outside or suspended from the outside in the casing of the transmission member The cost of finishing is not higher than in the case of shorter transmission components The constructive mass

  only reaches that needed anyway.

  According to an exemplary embodiment of the invention, it is provided that the support bearings rotationally supporting the transverse shaft are mounted on brackets which are suspended and centered in openings in a wall of the tube of rectangular section and fixed on machined surfaces of the

outer face of this wall.

  All the necessary bearings of the transverse shaft, as a rule three bearings, require the machining only of an external face

2683699

  of the transmission member housing The brackets carrying the already mounted bearings are only engaged from the outside in the centering openings of the brackets and fixed at the outer face on the edge of the opening. According to another more advantageous embodiment, it is provided that the bearings of the output shafts of the gear end mechanisms and the bearing of the input shaft of the central gear mechanism are centered in openings in the housing of the 'transmission member and fixed on the outer face of it so that even for these bearings, only a machining of the outer face of the

housing is necessary.

  In a preferred embodiment, the consoles of the support bearings of the transverse shaft and the bearings of the output shafts of the angle gear end mechanisms are then fixed to machined surfaces of the same wall of the tube. at section

rectangular.

  In the abovementioned embodiments, all of the machining operations for the support bearings of the transverse shaft and the bearings of the output shafts for the spreading discs are carried out in a single plane and therefore with a single

mounting on the workshop machine.

  The usual transmission assemblies for spreading discs work in an oil bath. For this reason, the transmission casing has an oil filling hole with filter and a rod-shaped dipstick, as well as one or more drain holes. In the spirit of a simpler finish, provision is made to arrange the oil filling orifice in the wall of the rectangular section tube where there are the openings for the output shafts of the end mechanisms to gear, and the oil drain holes in the wall perpendicular to

  this on which the input shaft is mounted.

  This configuration provides the advantage that the transmission casing can be machined entirely on only two walls perpendicular to each other, that is to say in only two planes, and thus with

only two machine clamps.

  As already indicated, provision is made for

  three support bearings for the transverse shafts, preferably located near the

  central mechanism and two end mechanisms.

  In this way, the surfaces to be machined at

  the outside of the tube are concentrated locally.

  Due to the great length, a considerable amount of oil would be necessary, even in the case of a reduction in the free cross-section of the rectangular section tube, to ensure that each of the transmission stages is continuously bathed in oil during the operation This must be guaranteed even in the case of sloping ground, it would require a full filling of oil It would be expensive and harmful to the environment due to the change

oil required.

  The invention makes it possible to remedy this drawback by filling the internal volume of the tube between its lower wall and the transverse shaft with filling bodies reducing the internal volume.

of the housing.

  By the use of these filling bodies

  wise, the free section of the transmission housing, namely its internal volume, is reduced at least partially without adversely affecting the characteristics of

  operation of the transmission stages.

  In the spirit of optimizing this arrangement, provision is made to leave free of the filling body only the space around the support bearings of the transverse shaft and around the central mechanism and the

end mechanisms.

  With the above-mentioned arrangement, only chambers with the total free cross-section are housed at the level of the transmission stages and the support bearings. In this way, only one level of oil filling should be provided, approximately at the height of the transverse shaft, because even for spreading work on sloping ground, each of the chambers is guaranteed to have a sufficient quantity of oil, without the oil getting

moves entirely to one side.

  Preferably, the filling bodies are made of a light oil-resistant material which must certainly allow a free flow of oil over it, but also have a sufficiently high resistance to the free flow of oil during work of spreading on sloping ground, so as to prevent the flow and accumulation of oil at the lowest point of the transmission housing The filling bodies are preferably made from closed-pore foam or an extruded plastic material. In this way a significant reduction in weight is obtained compared to the

  filling with oil which would otherwise be necessary.

  A further embodiment of the invention is characterized in that the rectangular section tube has on each of its front faces a flange for one of the covers and that each flange consists of two ribs projecting in lateral projection only along the vertical walls of the tube and two ribs cooperating with flush closure with the lower and upper walls of the tube projecting inwards

  in the inner section of the tube.

  By the aforementioned conformation, it is firstly guaranteed to have a sufficiently large internal section between the ribs projecting inside for the introduction and mounting of the filling bodies, and secondly to obtain the lowest possible height in the vertical plane, which is advantageous for having a tank of product to be spread of the largest possible dimension and thus of the largest possible capacity for a lower total height, which is essential for the center of gravity of the spreader produced under the

form of a worn material.

  Finally, according to an exemplary embodiment, the covers of the tube may have on their edge fasteners and / or guide means for the

transmission housing.

  Conformation of the tube into a tube with a square cross-section proves to be particularly advantageous, since the sets of gears of the transmission device can be accommodated while saving space, which generates

  total a footprint as small as possible.

  In another suitable variant, it is provided that the central mechanism and the two end mechanisms consist of the same gear sets, the diameter and the number of pinion teeth on the input shaft of the central gear mechanism and the pinions of the two end mechanisms on the transverse shaft on the one hand, as well as the diameter and the number of teeth of the other pinions meshing thereon, on the other hand, being identical through these arrangements , we minimize machining and workshop costs. In the aforementioned embodiment, it is possible in particular to choose the transmission ratio of each transmission stage is 1 / 1.33 In this way, the normalized PTO speed of 540 rpm is easily converted into a diet of 1000

  rpm at the spreading discs.

  The invention is described below in an embodiment shown in the drawings in which: Figure 1 is a schematic elevational view of a spreader seen from the rear in the direction of travel; Figure 2 is a vertical sectional view of the transmission housing; Figure 3 is a plan view partially in

section of the transmission housing.

  The spreader according to FIG. 1 has a storage tank 1 which, on each side, is reduced into a funnel towards a drainage well 2 The storage tank 1 is carried by a frame which is formed of

  vertical uprights 3 and a horizontal cross 4.

  The interior volume of the reservoir is crossed by an agitator shaft 5 which keeps the product to be spread in a state of flow, in particular in the vicinity of

  the upper end of the drainage wells 2 Au-

  above the wells 2, there are indicated metering members 6 which are adjustable by means of

actuators 7.

  Below each drainage well 2, is disposed a spreading disc 8 which receives the product to be spread leaving the drainage well 2 The two spreading discs 8, as it is evident in the figure 1, are separated by a relatively large interval. They are driven by the power take-off of a tractor to the three-point hitch from which the chassis is coupled with its vertical uprights 3 and a central joining device (not shown). The spreading discs 8 are driven by a drive assembly, preferably with adjustable speed, shown more precisely in FIGS. 2 and 3 The drive assembly has a transmission member generally designated by the reference 10 which consists of a central bevel gear mechanism 11, hereinafter called the central mechanism and two bevel gear end mechanisms 12 and 13, hereinafter called the end mechanisms The central mechanism 11 comprises a shaft inlet 14 coupled to the PTO 15 of the tractor The end mechanisms 12 and 13 each have an output shaft 16,17 and a hub 18,19 on each of which are mounted the spreading discs 8 by means

a quick coupler.

  The central mechanism 11 is connected to the end mechanisms 12 and 13 by a transverse shaft 20 which extends approximately over the whole

  the constructive width of the transmission member.

  This shaft is rotatably mounted on three support bearings 21, 22 and 23, which are each arranged near a transmission stage The central mechanism 11, the two end mechanisms 12 and 13 and the support bearings 21 , 22, 23 are housed in a casing 24 formed in a tube with a usual rectangular section on the market. In order to allow perfect centering and fixing operations of the parts making up the transmission member despite the long length of the tube, and in order to be able to meet the finishing tolerances on the tube, the bearings 21, 22 and 23 are mounted on support brackets 25, 26 and 27 which are suspended in the tube 24 from the outside For this purpose, the tube 24 has, on the outer face 28 of its upper wall 29, machined bearing surfaces for the consoles -support 25, 26 and 27 These consoles are centered in corresponding openings -of this

wall 29.

  On the same wall 29, corresponding bearing surfaces are provided for the bearings 30, 31 of the output shafts 16, 17 of the two end mechanisms, which are also centered in the openings of this wall by corresponding bearing housings. Inside the casing 10 are simply arranged free bearings 32,33 for the output shafts of the

end mechanisms 12.13.

  Similarly, the bearing 34 of the input shaft 14 of the central mechanism is fixed on a bearing surface on the outer face 35 of the wall 36 of the tube located opposite the tractor on a bearing surface provided for this purpose. location, and the bearing housing is centered in a suitable opening in this wall 36. In the same wall are provided oil drain holes 37 (FIG. 2) with drain nuts 38, a filling hole with gauge 39 (Figure 2) being formed in the wall 29 which also supports the support brackets 25, 26 and 27 of the bearings 21, 22 and 23 All of the mechanical machining work is therefore limited to the outer faces of the two

  walls 29, 36 perpendicular to each other of the tube 24.

  The tube 24 is closed on each of its faces by a cover 40,41. For the fitting of the covers 40,41, a flange is provided on the tube 24 which consists of two ribs 42,43 which do not protrude from the tube. that respectively in the direction and in the opposite direction of travel (Figure 3) In addition, the flange has closing ribs 44,45 projecting inwardly and cooperating with flush closure with the outer face of the upper and lower walls of the tube 24, these ribs 44, reducing the internal section of the tube 24, so that the height of the drive assembly is essentially exclusively defined by the height of the tube with rectangular section 24 Alternatively, the tube can be consisting of a profile, for example of aluminum, at the edges of which are formed by die through holes in which the covers, 41 can be fixed directly so as to eliminate any subsequent mechanical work For the same reasons, the covers can be produced in the form of injected plastic parts and have a groove on the inside.

  device in which a sealing is arranged.

  In order to minimize the quantity of oil required and to reduce the supply required during the draining, the transmission member 10 is arranged inside the tube 24, that is to say inside the tube 24, filling bodies 46,47 which are preferably made of oil-resistant synthetic foam or of extruded plastic The filling bodies 46,47 (see FIG. 2) are secured to the wall

  tube 24 and extend to just between

  below the transverse shaft 20 Only the space around the bevel gear mechanism 11 and the end mechanisms 12,13 as well as the bearings 21, 22 and 23 arranged in the vicinity is free of filling bodies so as to form in these places of the rooms of

  height corresponding to the interior section.

  Transmission case is filled with oil

  approximately to the level of the trans-

  versal 20, thus ensuring by the presence of the chambers around the transmission stages and the support bearings that the gears are sufficiently supplied with oil This also applies for displacements on sloping ground, because when the assembly of drive 10 is in an inclined position, the oil is retained in each chamber at least up to the height of the filling bodies Also, in the case of changing inclinations, faster delivery to a uniform level inside the 'together

10 drive is guaranteed.

  The central mechanism 11 and the end mechanisms 12, 13 are made up of identical gear pairs (FIG. 2) which each have a transmission ratio of 1 / 1.33 in speed, so that the normalized speed of the clutch force of a conventional tractor (540 rpm) is converted to around 1000 rpm

  at the spreading discs 8.

  In order to be able to use the same drive unit on modern high-performance tractors which have a speed of 1000 rpm on the PTO, the two bevel gears of the central mechanism are interchangeable with each other so as to be made in conjunction with the mechanisms end of a transmission ratio of 1/1 The brackets 25, 26 and 27 of the support bearings 21, 22 and 23 of the transverse shaft as well as the flanges of the bearings 30, 31 and 34 of the input shafts and outlet 14, 16, 17 can be made of injected plastic parts or

  light metal foundry parts.

Claims (13)

  1 drive assembly for a centrifugal spreader of granular products liable to flow, comprising at least two spreading discs very distant from each other, consisting of a transmission member housed in a housing having a central bevel gear mechanism, the input shaft of which can be coupled to the PTO of a tractor and, arranged on each side of the central mechanism, connected to the latter by a transverse shaft, end mechanisms with angle gear, a spreading disc (8) being mounted on the output shaft of each of them, these output shafts being arranged in a direction substantially perpendicular to the input shaft, all of the the transmission member being mounted on bearings in the casing, characterized in that the casing (24) of the transmission member (10) is shaped according to a usual rectangular section tube and the bearings (21,22, 23,30,31,34) of arb res (16,17,20) are centered and rest on machined surfaces of the outside face of the tube of rectangular section, and in that this one is closed on its two front faces by covers (40,41).   2 drive assembly according to claim 1, characterized in that the bearings (21,22,23) supporting the transverse shaft (20) are arranged on brackets (25,26,27) which are suspended and centered in openings in a wall (29) of the rectangular section tube (24) and fixed to machined surfaces on the external face of this wall. 3 Drive assembly according to one of   claims 1 or 2, characterized in that the   bearings (30,31) of the drive shaft (16,17) of the end mechanisms (12,13) and the bearing (34) of the input shaft (14) of the central mechanism (11) are centered in openings in the transmission housing   (24) and fixed to its outer face.   4 Drive assembly according to one of   claims 1 to 3, characterized in that the   brackets (25,26,27) of the bearings (21,22,23) of the transverse shaft (20) and the bearings (30,31) of the drive shafts (16,17) of the end mechanisms (12 , 13) are fixed on machined surfaces of the external face of the same wall (29) of the section tube rectangular (24).   Training set according to one of   claims 1 to 4 showing an orifice for   oil filling with filter and a rod-shaped dipstick and one or more oil drain holes, characterized in that the oil filling hole is provided in the wall (29) of the section tube rectangular (24) which has the openings for the drive shafts (16,17) of the end mechanisms (12,13) and in that the oil drain holes (37) are provided in the perpendicular wall (36) which supports the bearing of the shaft inlet (14).   6 Drive assembly according to one of   claims 1 to 5, characterized in that three   bearings (21,22,23) are provided for the transverse shaft (20), these bearings being mounted respectively near the central mechanism (11) and the mechanisms end (12,13).   7 Drive assembly according to one of   claims 1 to 6, characterized in that in the   rectangular section tubes (24), between its lower wall and the transverse shaft (20), are arranged filling bodies (46, 47) reducing the space inside of the housing.   8 Drive assembly according to one of   claims 1 to 7, characterized in that only   the space surrounding the bearings (21,22,23) of the transverse shaft (20) as well as the central mechanism (11) and the end mechanisms (12, 13) is free of bodies filling (47).   9 Drive assembly according to one of   claims 1 to 8, characterized in that the   filling bodies (47) are made of a light oil-resistant material, for example a closed-pore foam, an extruded plastic body or similar.   Training set according to one of   claims 1 to 9, characterized in that the tube   of rectangular section (24) has on each of its front faces a flange for one of the covers (42,43) and in that each flange consists of two   linear ribs projecting laterally uni-   along the vertical walls of the rectangular section tube, and two ribs (44,45) cooperating flush with the upper and lower walls of the rectangular section tube (24) and projecting inside the inner section of it.   11 Drive assembly according to one of   claims 1 to 9, characterized in that the tube   of rectangular section (24) is an extruded aluminum tube having axial holes used for the fixing the covers (40,41).   12 Drive assembly according to one of   claims 1 to 11, characterized in that the   covers (40,41) are made of plastic and have a seal incorporated on that of their sides acting in cooperation with the face   front of the rectangular section tube.   13 Drive assembly according to one of   claims 1 to 12, characterized in that the   covers (40,41) of the rectangular section tube have fixing and / or guiding means for   the transmission housing on the chassis (3,4).   14 Drive assembly according to one of   claims 1 to 13, characterized in that the tube   rectangular section (24) is a square section tube. Training set according to one of   claims 1 to 14, characterized in that the   central mechanism (11) and the two end mechanisms (12, 13) consist of the same sets of pinions in which the section and the number of teeth of the pinions on the input shaft (14) of the central mechanism (11 ) and pinions on the transverse shaft (20) of the two end mechanisms (12,13) on the one hand, and the section and the number of teeth of the pinions   meshing with these on the other hand, are identical.   16 Drive assembly according to one of   claims 1 to 15, characterized in that the   transmission ratio of each transmission stage is 1 / 1.33.   17 Drive assembly according to one of   claims 1 to 16, characterized in that the   two pinions of the central mechanism (11) are interchangeable.