|Publication number||US3825232 A|
|Publication date||Jul 23, 1974|
|Filing date||Dec 14, 1972|
|Priority date||Dec 16, 1971|
|Also published as||DE2261474A1|
|Publication number||US 3825232 A, US 3825232A, US-A-3825232, US3825232 A, US3825232A|
|Original Assignee||Pecorari P|
|Export Citation||BiBTeX, EndNote, RefMan|
|Referenced by (15), Classifications (6)|
|External Links: USPTO, USPTO Assignment, Espacenet|
'jnited StatesPate i ecorari nu 3,825,232 "1451 Jul 23, 1974 [54 APPARATUS FOR TRANSPORTING AND MIXING CONCRETE  Inventor: Piercelestino Pecorari, Via Pagliani,
41100 Modena, Italy  Filed: 1 Dec. 14,1972  Appl. No.: 315,172
 Foreign Application Priority Data Dec. 16, 1971 Italy 40155/71 52 us. on 259/1 77 R 511 Int.'Cl,; B28c 5/20  Field of Search," 259/175, 176, 177 R, 177 A, 259/3, 14, 30, 57, 81 R, 81 A, 89, 90; 74/574; 248/7, 15, 26
Primary Examiner-I-larvey C. I-lornsby Assistant ExaminerPhilip R. Coe Attorney, Agent, or FirmSteinberg and Blake An apparatus for transporting and mixing concrete. The apparatus includes a vehicle having an elongated chassis which terminates in a rear end, and situated over this chassis is a rotary concrete mixer which has a rear discharge end at the region of the rear end of the chassis and a front end distant from its rear discharge end. A supporting structure supports the rotary concrete mixer at its front end for rotary movement about a given axis of rotation, and this supporting structure is interconnected with the chassis by way of a universal joint structure which gives the concrete mixer the capability of moving in all directions with respect to the chassis. A frictional resistance is pro vided at the universal joint structureto frictionally resist movement of the concrete mixer with respect to .the chassis and the universal joint structure to a given extent, so that in response to forces transmitted to the concrete mixer from the chassis it will be possible for the concrete mixer displace itself with respect to the chassis when the forces are'great enough to overcome a the frictional resistance.
8 Claims, 4 Drawing Figures and mixing concrete the above drawbacks. v
BACKGROUNIJOF THE-INVENTION The present invention" relates to apparatus for transporting and mixing concrete.
Thus, the present invention relates to generally knownve-hicles such as trucks which carry on their chassis rotary concrete mixers from which it is possible to pour concrete at a desired location, with the rotary concrete mixer capable of carrying out itsrotary move ment while the vehicle is in transit. I
Although appar'atusiof the above type is in "general well known, -it suffers from certain'disadvantages, particularly with respect to the manner in which the rotary concrete mixer is connected to the chassis of the vehicle';.Thus, the rotary concrete mixer has a reardischarge end and distant from the latter a front end where'the rotary concretemixer is supported at least in part for rotary movement by a supporting Structure which; is directly fixed to the chassis. Because of the rigid fixing of thisjsupporting structure directly to the chassis of the vehicle, all'o'f the forces encountered by v the vehicle are transmitted to the support at the front end of the rotary concrete mixer. When it is remem- -bered that the vehicle-willnormally travel overburnpy roads, it will-be 'seenthat the forces transmitted to the support for the front end of the rotary concrete mixer may be considerable. The action of these forces result in 'a relatively short timein considerable damage, :particularly when it is remembered that the rotary concrete mixer normally.- rotates to carryout its concrete mixing operationwhile the .vehicle is in transit. Thus, it is not uncommon for the structure which supports the front end of the concrete mixer to become deformed and even to fail in a relatively'short time, while at the same 'time'the drive which rotates the concretemixer SUMMARY THE INVENTION Itis accordingly a" primary object of the present invention'to provide an apparatus capable of transporting While at the'same time avoiding It is in particular an object of to provide an apparatus of the above general type which iscapable of absorbing forces in such-a way as to prevent undesirabledamage. It isparticularly an object of the present adjusted with respect to the extent to which forces are capable of being absorbed. In addition it is an object of the present invention to providea structure of the above general type which is exceedingly rugged and capable-of operating reliably over a longperiod of time while at thesame time being simple and relatively inexpensive.
In particular, it isan object of the present invention to achieve the above'objects with a construction which PAR TUs-FoR TRANsPoRnNG AND MIXING does not in any way interfere wit the normal-conventionalbperation of a concrete mixer. v I Also, it is 'an object of the present invention to provide an apparatus of theabove type in which the'stability of the concrete mixer is assured against any possibility of tipping of the vehicle and the concrete mixer thereon. I y
In accordance with the invention the apparatus in;- cludes a vehicle which has an elongated chassis-terminating'in a rear end. Situated-over-this chassis is a rotary concrete'rnixer which has arear discharge end at the region of the rear end of the-chassis..This concrete mixer has a front end distant from its rear discharge end and carried by a support means which is operatively connected with the ,front end of the rotary 'concrete mixer so as to contributeat least in part to the support of the rotary concrete mixer for rotary movement about a predetermined axis of rotation. This ax-is of rotation normally is higher at the region, of the rear discharge end of. the. mixer than at the. front end thereof. The support means connected to't'he front end of the rotary concrete mixing means is connected to the chassis byway of a universal joint means which provides the rotary concrete mixing means with the capability of moving in all directions with respect'to the chassis. Afriction means is operatively connected with R the universal joint means for yieldably resisting the movement of theconcrete mixing means'with respect to the chassis at the universal joint mean-s. t BRIEF DESCRIPTION 'o DRAwiNos L The invention is illustrated by way of example in the accompanying drawings which form part of this application and in which:
FIG. 1- is a side elevation of an apparatus according to theinvention showing in section part of a universal joint means-for interconnecting a support means fora rotary concrete mixer means with a chassis of the illustrated vehicle; 7
FIG. 2 is a fragmentary top plan view showing the structure of the invention, which is situated at the region of the front end of the concrete mixing means,.at
the present invention invention to provide a construction of the'above type which can be an enlarged scale as compared to FIG. 1, the axis of the iconcrete mixer being-turned through in'FIG. 2, with respectitothe orientation of this axis in FIG. 1;
FIG. 3 is a top plan view, on a scale which is enlarged as compared to F IG. 2, of the structure of the invention which is situated at one side of the support means for the.- rotary concrete mixer, the structure which is shown in FIG. 3 being illustrated at the right in FIG. 2 with the structure of FIG. 3 being displaced through with respectto the orientation .of the structure in FIG. 2; and
FIG. "4 is a vertical sectional elevation showing further details of the structure of the invention, the structure'being shown horizontally in FIG. 4 for the sake of convenience, it being understood that actually the structure of FIG. 4 is oriented at an angle which is displaced by 90 in a counterclockwise direction from the position of the structurewhich is shown in FIG. 4.
" DESCRIPTION OF PREFERRED EMBODIMENTS Referring first to FIG. '1, there is illustrated therein I vehicle such as a truck which has a chassis 10 which terminates in a rear endsituated at the rightin FIG. 1.
Situatedover the chassis 10 is a rotary concret mixing means 1 whichin itself is conventional, this rotary concrete mixing means 1 having a rear discharge end, shown at the right in FIG. 1, located at the region of the rear end of the elongated chassis 10 of the vehicle. The structure shown at the right in FIG. 1 associated with the rear discharge end of the rotary concrete mixing means 1 is conventional and forms no part of the present invention.
The rotary concrete mixing means 1 has an axis of rotation 2 which is illustrated in FIGS. 1 and 2, and it will be noted that the rotary concrete mixing means 1 has distant from its rear discharge end a front end supported for rotary movement by a support means 3 which contributes at least in part to the support of the rotary concrete mixing means for rotation about the axis of rotation 2. Thus it will be noted that the axis of rotation 2 is higher, normally at the rear discharge end of the rotary concrete mixing means than at the front end thereof. Thus, the structure is shown in FIG. 1 at its normal operating position during mixing of the concrete. Of course when the concrete is discharged the structure is tilted so that the concrete will pour out of the discharge end of the concrete mixing means 1. The support means 3 is in the form of a circular housing which carries in its interior a ball bearing assembly 11 which is schematically indicated, this assembly being situated along a circle 12 which surrounds the axis 2 with the center of the circle 12 being situated in the axis 2, and of course the circle 12 is located in a plane which is normal to the axis 2. The bearing 11 serves to support for rotary movement a ring gear having internal teeth and forming part of a drive means for rotating the rotary concrete mixing means 1, this drive means including the hydraulic driving motor 4 which is directly carried by the support means 3 in the manner which is schematically illustrated. In a known way, when the drive means 4 is operated the transmission within the housing 3 will serve to rotate the rotary concrete mixing means 1 about its axis of rotation 2.
In accordance with the invention the support means 3 is interconnected with the chassis 10 by way of a universal joint means which includes the components 5, 6, 16, and 13. Thus, the universal joint means includes a pair of rigid arms 5 which are, for example, integral with and project laterally in opposed directions from the support means 3 transversally of the elongated chassis 10. These arms 5 terminate in outer bodies respectively having rearwardly directed flat vertical end faces 15 for clearing the rotary concrete mixing means 1. These bodies at the outer ends of the arms 5 are formed with vertical bores, as is apparent from the sectional illustration of this body in FIG. 4. Also as is apparent from FIG. 4, each body at the outer end of the arm 5 is formed with upper and lower curved surfaces which respectively form parts of spheres. Thus, the body at the outer end of each arm 5 has an upper concave curved surface receiving and engaged by the lower convex surface of an upper bearing member 16, the lower surface of which forms part of the same sphere as the upper concave curved surface of the body 5. At its lower surface the body 5 is formed with a convex curvature forming part of the sphere and engaging a concave curved surface of a lower bearing member 6 whose upper concave surface forms part of the same sphere as the lower convex surface of each body 5.
The chassis includes the chassis components 7 which may be directly welded to the remainder of the chassis 10 as shown in FIG. 4, and these chassis components 7 respectively have upper horizontal wall portions directly engaging the lower flat surfaces of the bearing members 6, respectively. The upper bearing member 16 and the lower bearing member 6 which respectively engage the upper and lower end surfaces of each body at the end of each arm 5 are formed with openings aligned with the vertical bore of the body at the end of each arm 5, and the horizontal wall portion at the upper end of each chassis component is also formed with an opening 14 aligned with the openings through the bearing members 6 and 16 and the bore of the body at the end of each arm 5.
A friction means is formed by a bolt 8 extending through the axial bore of each body at the end of each arm 5. This bolt 8 has a head end engaging the top surface of each bearing member 16 and a bottom end extending into a chamber formed in the interior of the chassis component 7. At its bottom end each bolt 8 carries a nut which engages a spring-washer means 9, in the form of cup springs, for example, these members 9 engaging the lower surface of the horizontal wall portion of each chassis component 7, so that the friction means 8, 9, serves to press the bearing members 6 and 16 at each body toward each other and against the spherically curved surfaces at the upper and lower ends of the body at the end of each arm 5. As a result the friction means 8, 9 provides a given frictional resistance to movement of the bodies at the ends of the arms 5 with respect to the bearing members 6 and 16.
As is apparent from FIGS. 1 and 4, the bore through the body at the end of each arm 5 has a diameter sufficiently great to provide a clearance with respect to the shank of the bolt 8 which will enable the concrete mixing means 1 to tilt in a vertical plane in one direction or the other with the bodies at the ends of the arm 5 moving with respect to the bolts 8 and also with respect to the bearing members 6 and 16 to a given extent by slipping at the bearing surfaces which form parts of spheres as pointed out above. In this way in response to shocks which tend to displace the axis 2 in a vertical plane, instead of any deformation or excessive stressing of any components the forces will be absorbed by frictional slipping between the bodies at the ends of the arms 5 and the spherically curved surfaces of the bearing members 6 and 16. It will be noted that the concrete mixing means 1 together with the support means 3 and the drive means 4 will all move as a single unit in response to such forces which tend to displace the structure in a vertical plane.
The openings 14 which extend through the horizontal wall portions of the chassis component 7 are elongated and extend along part of a common circle which is in a horizontal plane with the center of the circle being situated beneath the axis of rotation 2, and between the opposed ends of the concrete mixing means 1. The bolts 8 respectively have axes which normally coincide with the axis of the bores extending axially through the bodies at the ends of the arms 5, and these axes intersect the circle along which the openings 14 extend at the outer ends of a pair of radii which extend from the center of the circle along which the openings 14 extend and which respectively make angles of 45 with the horizontal projection of the axis 2 onto the plane which contains the circle along which the slots 14 extend. Initially these radii will extend substantially midway between the opposed ends of the elongated openings 14,
as illustrated most clearly in FIG. 2, so that the greatest degree of swinging movement in either direction about a vertical axis is provided with this arrangement.
The bearing members 6 and the horizontal wall portions of chassis component 7 have surfaces which engage each other, and at each side of the support means 3 these surfaces are formed one with a rib and the other with a groove which receives the rib, with the rib and groove extending arcuately along the same circle as the elongated opening 14, so that through this arrangement it is possible for the lower bearing member 6 and the structure supported thereon, including friction means 8, 9, to swing about the vertical axis which passes perpendicularly through the center of the circle along which the elongated openings 14 extend. It will be seen that in the illustrated example it is the upper horizontal wall portions of the chassis components 7 which are formed with the elongated arcuate ribs 13 received in corresponding mating grooves extending across the lower surfaces of the bearing members 6, with the ribs- 13 projecting beyond the bearing members 6 and beyond the opposed ends of the lower grooves formed therein, as is clearly apparent from FIG. 2. Also it will be noted that the openings 14 which extend through the upper horizontal walls of the chassis component 7 also extend through the ribs 13 so that while the ribs 13 remain stationary it is possible for the lower bearing members 6 together with the bodies at the ends of the arms 5 and the upper bearing members 16 together with the friction means 8, 9, to move along the ribs 13 and the horizontal wall portions of the chassis component 7 in response to lateral forces which tend to swing the rotary concretemixing means 1 about a vertical axis passing through the center of the circle along which the openings 14 extend.
It will be noted that the friction means 8, 9, serves to yieldably oppose both movement of the concrete mixing means 1 in a vertical plane as well as movement thereof in a horizontal plane. The bolts 8 and the nuts carried thereby are adjusted so as to provide through the spring-washer means 9 a given force of friction which in response to forces of sufficient magnitude will provideslippage at the friction surfaces of the universal joint means in the manner described above.
Thus, with the structure of the invention the concrete mixing means is not rigidly fixed at its front end to the chassis of the vehicle. Instead it is capable of shifting with respect to the chassis 10 with the axis 2 being capable of describing a cone whose apex is located at the region of the rear end of the concrete mixing means. Such shifting will occur due to stresses transmitted through the universal joint means of the invention to the support means 3 and through the-latter to the con-' crete mixing means in such a way that the possibility of v yielding -to these forces at the friction surfaces of the universal joint means of the invention provides stability to the entire apparatus, protecting against any possible tilting or falling of the vehicle over on its side, assuring a full absorbing of excessive forces by the frictional slipping in the event that excessively large working stresses are unexpectedly encountered. With the above-described symmetrical arrangement according to which the radii which extend through the intersections of the axes of the bolts 8 with the circle along which the slots 14 extend respectively make 45 with the horizontal projection of the axis of rotation onto the plane which contains the circle along which the slots 14 extend, it is possible to absorb both axial and radial thrusts,- so that a complete protection is provided for the mounting of the concrete mixing means with a long operating life assured with the simple rugged structure of the invention.
Of course, the curved surfaces at the upper and lower ends of each body at the end of each arm 5 respectively form parts of concentric spheres.
What is claimed is: v
l. ln-an apparatus for transporting and mixing concrete, a vehicle having an elongated chassis terminating in a rear end, rotary concrete mixing means situated over and carried by said chassis, said rotary concrete mixing means having a rear discharge end situated in the region of the rear end of said chassis and having a front end distant from said rear discharge end, said rotary concrete mixing means having an axis of rotation which extends generally longitudinally of said chassis and which is normally inclined with said axis having a higher elevation at the rear discharge end of said concrete mixing means than at the front end thereof, support means operatively connected to said front end of said concrete mixing means for contributing at least partly to the support of said concrete mixing means for rotation about said axis, universal joint means connected between said support means and said chassis for providing for said mixing means the capability of moving in all directions with respect to said chassis, and friction means operatively connected with said universal joint means for frictionally resisting movement of said concrete mixing means and said support means therewith with respect to said chassis at said universal joint means, drive means operatively connected with said rotary concrete mixing means for rotating the latter about said axis, said drive means being carried by said support means for movement together with the latter and said rotary concrete mixing means at said universal joint means with respect to said chassis, said universal joint means including a pair of opposed lateral arms respectively fixed to and projecting laterally from said support means in opposite directions transversely of said chassis, said arms terminating in bodies each of which has upper and lower surfaces which respectively form parts of spheres and each of which is formed with a substantially vertical bore extending between said upper and lower surfaces, upper and lower bearing members engaging the upper and lower surfaces of each of said bodies and respectively having in engagement with the latter surfaces, surfaces which respectively form parts of spheres of the same curvature as said upper and lower surfaces of each body, said upper and lower bearing members at each of said bodies being respectively formed with openings aligned with said bore of each body, said friction means including a bolt extending through the bore of each body and through the openings of the upper and lower bearing members which engage each body, said bolt being operatively connected with said chassis and carrying at one end a nut and a spring-washer means for urging the upper and lower bearing members at each body toward each other and against the upper and lower surfaces of each body with a force which frictionally resists turning of each body with respect to said bearing members in response to tendencies of said concrete mixing means to move in a direction which displaces said axis in a vertical plane.
2. The combination of claim 1 and wherein said chassis has a horizontal wall portion beneath each of said lower bearing members directly supporting the latter and formed with an opening through which each bolt extends, said chassis being formed beneath each horizontal wall portion with a chamber which accommodates said nut and spring-washer means, said bolt having at each body an upper head end engaging the upper bearing member which engages the upper surface of each body,
3. The combination of claim 1 and wherein said chassis has beneath each of said lower bearing members a horizontal wall portion formed with an opening through which said bolt of said friction means extends for connecting said bolt to said chassis, said openings of said horizontal wall portions of said chassis being elongated, of arcuate configuration, and extending along a common circle which is situated in a horizontal plane and which has a center situated beneath said axis of rotation of said concrete mixing means between said front and rear ends thereof.
4. The combination of claim 3 and wherein said bores of said bodies respectively have axes which intersect said circle respectively at the outer ends of a pair of radii of said circle which respectively extend from the center of said circle at angles of 45 with respect to the horizontal projection of said axis of rotation of said concrete mixer onto the horizontal plane in which said circle is located.
5. The combination of claim 4 and wherein said radii respectively extend substantially midway between opposed ends of said elongated arcuate openings when said projection of said axis of rotation of said concrete mixer extends precisely forwardly and rearwardly with respect to said chassis.
6. The combination of claim 5 and wherein each of said horizontal wall portions of said chassis and said lower bearing member engaging the same respectively have surfaces directly engaging each other with one of said surfaces being formed with a rib and the other of said surfaces being formed with a groove receiving said rib, and said ribs and grooves being concentric with said circle.
7. The combination of claim 6 and wherein each of said lower bearing members is formed with said groove while each of said horizontal wall portions has an upwardly extending rib received in said groove, and said elongated arcuate opening at each of said horizontal wall portions extending through each rib.
8. The combination of claim 7 and wherein said upper and lower surfaces of each body which respectively form parts of spheres are respectively concave and convex, said upper bearing members respectively having lower convex surfaces engaging said upper concave surfaces ofsaid bodies and said lower bearing members respectively having upper concave surfaces engaging said lower convex surfaces of said bodies.
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|U.S. Classification||366/62, D12/95|
|International Classification||B28C5/42, B28C5/00|