US2525573A

US2525573A - Concrete mixer

Info

Publication number: US2525573A
Application number: US771414A
Authority: US
Inventors: Anthony G Zicovich
Original assignee: ARTHUR W CALDWELL
Current assignee: ARTHUR W CALDWELL
Priority date: 1947-08-30
Filing date: 1947-08-30
Publication date: 1950-10-10
Anticipated expiration: 1967-10-10

Description

Oct. lO, 1,950 A, G. zlcovlcH 2,525,573

coNcRE'm; MIXER Filed Aug. 50, 1947 3 Sheets-Sheet l A. G. ZICOVICH CONCRETE MIXER Oct. 10, 1950 3 Sheets-Sheet 2 Filed Aug. 30, 1947 Arme/vir Oct. 10, 1950 A. G. zlcovlcH 2,525,573

coNcEEEE MIXER Filed Aug. so, 1947 s sheets-sheet s I l 1lllnmullulllullllllmmfwii 5 ar M7@ MK- rrae/Yfr Patented ct. l0,

UNITED STATES PATENT `OFFICE Anthony i'iicovioh,` San Jose, Calif.,A assigx'or of one-half to Arthur W. Caldwell, San Jose,

Calif.

18 Claims. l

This invention relates to concrete mixers and is concerned more particularly with such apparatus embodying a non-rotatable mixing tank and means for providing.. an elevated point of discharge for the concrete.

In the trucking of `concrete mixes from s, central mixing plant tothe construction job the useiulness of thepug mill concrete mixers embodying a non-rotatable mixing tank has been limited materially by the low level` of the discharge means and by the difficulty of eiecting discharge of the complete batch of concrete from the tank. The instant invention has for its general object the provision of improved concrete mixers of the above type which overcome the above-noted dis-` advantages and which provide for easy discharge of the complete batch of concrete at a desirable high elevation with reference to the` mixer truck as well as to facilitate loading of either Wet or dry mixtures into the mixing tank and mixing or agitation of the concrete mix while en route from the batch plant to the construction job.

The above and other objects of the invention will be apparent from the following description of certain preferred embodiments, as illustrated in the accompanying drawings, in which.:

Figure 1 is a side elevational view, partly in section, of a concrete mixing truck having a, pug mill mixer thereon embodying the instant invention, the mixer being shown in section.

Figure 2" is a rear elevation of the mixer.

Figure 3 is a iront elevation of the mixer.

Figure 4 is a transverse sectional View of the mixer taken as indicated by the line 4 4 in Figure l, the mixing blade being shown in a different operative position.

Figure 5 is a fragmentary plan view of the rear end of the mixer.

Referring to Figures l to 4, the mixing truck of the present invention includes a truck' chassis I0 having a cab II` and provided with the usual supporting Wheels, only the rear wheels being shown. A stationary mixing tank I2 of the conventional pug mill type is supported on the truckchassis, and the mixing tank I2 is open at the top in a conventional manner With the top opening being defined by upright ange portions I2a.

Within the tank I2 there is a mixing assembly including a central shaft I3 upon which a spirally arranged mixing and progressing blade I4 is mounted by suitable radial arms I6. Suitable diagonally disposed bracing rods are alsoV provided ior the blade I4. The outer edge or the spiral blade I4 is formed asa resilient extension Ma oi rubber materialrwhich eects a; clean sweep i, a conventional pneumatic cylinder 3i.

around thetwall of the tank while. yielding to permit passage of, rocks in themixture. The resilient blade portion Illa is bolted between a metal support strip I 4bwhich is carried by the support arms I6 and ametal clamping strip Ide. The radial dimension.` of the unsupported edge of the resilient portion Maof the mixing blade is coinparable to thelargest diameter of rock in the aggregate employed for the` concrete` mixture. The drive for theishaft I3 (Figures l and 4) may be asuitable form of housed chainy and sprocket drive connection including a connection lII` from the shaft I3 to an idler` shaft I8, a drive connection I9 from the idler` shaft I8 toa second idler shaft 2B, and a` drive connection 2l from the idler shaft ZI! to a drive shaft 22. The drive shaft 22 is driven through a suitable clutch mechanism 23 from` a power take-off shaft 24 extending to the` conventional trucktransmission Which has the usual gear shift lever associated therewith. A clutch control linkage 25 extends from the clutch 23 to the cabfI I.

` An elevated discharge of the concrete mix is provided` at the `rear of the mixer, and preferably closely adjacent aside thereof to provide for iiexibility in the point of discharge of the miX either rearwardly or to the side of the mixer. The rear wall "261 ofthe mixeris providedwith a rearwardly oisetportion: 26a providing an :arcuate discharge panfssage disposed out of the path of the blade. In its lower portionthe discharge passage has a discharge opening leading. to a discharge ramp 21. A gate2'8is pivoted on the wall portion 26a at 2B and has pivoted thereto the plunger of The cylinder 3|` ispivotally supported at 32 in spaced brackets 33 and is operable to move the gate 28 of the chute 3Ii is supported by a chain 4-I whose upper end has a vertical pivotal mounting at l2V in verticalv alignmentJ with the pivoted support 39 of the discharge chute. i

The blade structure. of the inventionhas in additionto the spiral mixing blade I4, a plurality of lifting or discharga blades 46, and as` shown, two opposite lifting blades 46 are provided which-` are helically shaped tocorrespond to the mixing` blade I4. The blades 46 are also mounted on the shaft I3 by suitable radial arms IS, and each blade d6 includes a metal body portion 46c having bolted thereto a, resilient radial or side edge portion liib, and a resilient end portion or strip c. One of the lifting blades 4% is mounted with the mixing blade Illa, so that the resilient edge portion lila thereof serves also as the edge 46D of the lifting blade. Referring to Figure 4, it will be noted that the wide end of va blade 46 is of a width corresponding to the width of the recessed or offset discharge passage 26a. As seen in Figure 5, the wide end of the tapered lifting blade structure, as well as the end of the spiral blade lli, depart from the general curvature of their helical shape and are disposed substantially at right angles to the adjacent end wall of the tank.

Referring to Figure 5, it will be noted that the immediate end portion of the spiral mixing blade ifi has a small straight section adjacent the end wall 2t, and this small straight `portion is occupied by the end strip ctc of the lifting blades. 'Ihis edge portion operates closely against the end wall so that any material picked up by a lifting blade will be elevated along the end wall until it arrives at the recessed end wall portion 26a. The discharge chamber provided by the wall portion 26a allows for discharge of the material elevated by the lifting blade over approximately 90 of its travel when it will flow down onto the discharge ramp 2l if the gate 28 is open. When the gate 28 is in its inclined closed position, as shown in Figure 1, it covers the inner portion of the discharge ramp 2l and diverts the material back into the tank.

As previously explained, the drive for the mixing and progressing blade ill and for the lifting blades il@ provides for counterclockwise rotation thereof, as viewed in Figure 4, so that the material is progressed by the blade toward the rearward end of the tank into cooperation with the lifting blades for elevation thereby to the discharge opening. The side edges of each lifting blade engage both the adjacent end and side walls to lift the material up the corner formed therey between. the lifting blade structure and its shaping to conform to the spiral of the mixing and progressing blade places the blade in an-inclined position relative to the end'wall 28 and the adjacent side wall. In this way concrete is pocketed between a lifting blade and the tank walls for elevation to the discharge opening. The resilient edge Ilia of the progressing blade provides for a clean sweep around the wall of the tank so that substantially all of the material will be progressed to the discharge Zone through which the blades 116 travel. At the same time the resilient edge Ma will yield if a stone does become lodged between it and the wall of the tank so that no jamming will occur. The front wall of the tank is engaged by a radial blade i3 which extends between the shaft and the blade Ui, and which is constructed similarly to the blade le to provide a resilient edge portion. It will be noted that the wiping action of the resilient blades M, i3 and 46 clean the respective walls of the tank during each rotation thereof.

While I have shown and described certain preferred embodiments vof the invention, it is apparent that the invention is capable of variation and modification from the` forms shown so that its scope should be limited only by the scope of the claims appended hereto.

f I claim: Y 1 In a concrete mixer, a frame, a stationary It will be noted that the mounting of mixing tank on Said frame having a discharge opening at an elevated position in an end wall thereof, means providing a recessed discharge passage offset with respect to said wall and extending upwardly from the bottom of said discharge opening, means disposed within the tank for progressing concrete therein toward said end wall, and a concrete elevating blade travelling through said tank adjacent said end wall and a contiguous side wall portion for picking up and carrying concrete to the recessed and offset discharge passage, said blade including detachable rubber edge portions for operation closely against the tank walls to thereby elevate substantially all of the pick-up concrete ingredients to said discharge opening without effecting appreciable separation of said ingredients.

2. In a concrete mixer, a frame, a stationary mixing tank on said frame having a discharge opening at an elevated position in a wall thereof adjacent the rear of the frame, a recessed discharge passage formed in said wall and extending upwardly from said discharge opening, means disposed within the tank for progressing concrete therein toward said wall, and concrete elevating means travelling through said tank adjacent said wall for picking up and carrying concrete to the discharge opening, said elevating means extending in the direction of progressing of concrete through said tank and being mounted to operate closely against the interior of the tank to thereby elevate substantially all of the pickedup concrete ingredients to said discharge opening without effecting appreciable separation of the ingredients.

3. In a concrete mixer, a frame, a stationary mixing tank on said frame having a discharge opening at an elevated position in an end portion thereof, a recessed discharge passage at said end portion of said tank offset outwardly from said portion and extending upwardly from the bottom `of said discharge opening, means disposed within the tank for progressing concrete therein toward said end portion and a concrete elevating blade travelling through said tank adjacent said end portion for picking up and carrying concrete to the discharge opening. li. In a concrete mixer, a, frame, a stationary mixing tank on said frame having a discharge opening at an elevated position in an end wall thereof, a recessed discharge passage formed in said end wall and extending upwardly from said discharge opening, means disposed within the tank for progressing concrete therein toward said end wall, and a concrete elevating blade travelling through said tank adjacent said end wall and a contiguous side wall portion for picking up and carrying concrete to the discharge opening, said blade having rubber edge portions for operation closely against the tank walls to thereby elevate substantially all of the picked-up concrete ingredients to said discharge opening without effecting appreciable separation of said ingredients.

5. Ina concrete mixer truck of the type for use in transporting and mixing batches of concrete, a stationary mixing tank of generally cylindrical contour having a flanged open top, a spiral mixing and progressing blade mounted coaxially within the tank and disposed to move material toward an end wall thereof having a discharge opening at an elevated position thereon, a discharge ramp extending outwardly from said discharge opening, an offset portion of said wall extending upwardly from said opening to provide al discharge passage overlying a portion of said ramp, an elevating blade mountednforrotation with said spiral biadeand disposed `to carry material upwardly to said discharge passage, and a gate for said opening havinga closed position in which it is positioned to 'deflect material from said discharge `passage back into said-tank.`

6. In a concrete mixer truck of the type for use in transporting and mixing batches ofconcrete, a stationary mixing tank or generally cylindrical contour having a flanged open top, a spiral mixing and progressing blade mounted coaxially within the tank and disposed to move material toward an end` wall thereof having a discharge opening at an elevated position thereon, a discharge ramp extending outwardly from said discharge opening, an oiisetportion of said Wall extending upwardly from said opening to provide a discharge passage overlying a portion of said ramp, an elevating blade mounted for rotation with said spiral blade and disposed to carry material upwardly to said discharge passage, a gate for said opening pivo-ted at its upper end to said oifset wall portion and having a closed position in which it is positioned to deiiectmaterial from said discharge passage back into said tank, and a fluid-actuated cylinder mechanism for operating said gate.

7. In a concrete mixer truck of the type for use in transporting and mixing `batches of concrete, a stationary mixing tank of generally cylindrical contour having a flanged open top, a spiral mixing and progressing blade mounted coaxially within the tank and disposed to move material toward an end wall thereof having a discharge opening at an elevated position therein, a discharged ramp extending outwardly from said discharge opening, an offset portion 'of said wall extending upwardly from said opening to provide a discharge passage overlying a portion of said ramp, an elevating blade mounted for rotation With said spiral blade and disposed to travel closely adjacent both the end and side walls of the tank and carry material upwardly to said discharge passage, and a gate for said opening having a closed position in which it is positioned to deflect material from said discharge passage back into said tank.

8. In a concrete mixer, a stationary mixing tank having an elevated discharge opening and a f concrete elevating zone adjacent thereto, said zone being defined at least in part by a recessed wall portion of said tank extending above said discharge opening, a concrete progressor for progressing the concrete mix into said elevating zone, and elevating means travelling through said zone for picking up and carrying concrete mix to the discharge opening.

9. In concrete mixer, a stationary mixing tank having an elevated discharge opening and a concrete elevating zone adjacent thereto, said zone being defined at least in part by a recessed wall portion of said tank, a concrete progressor for progressing the concrete mix into said elevating zone, and an elevating blade travelling through said Zone for picking up and carrying concrete mix to the discharge opening and having a flexible edge portion for operation closely against the tank Wall to thereby elevate substantially all of the picked-up concrete ingredients to said discharge opening without effecting appreciable separation of said ingredients.

l0. In a concrete mixer, a frame, a stationary mixing tank having an elevated discharge opening and a concrete elevating Zone adjacent therelli to, said Zone being' dened atleast in part by d recessed discharge passage adjacent said elevating zoneand being offsetoutwardly therefrom and extending upwardly from the bottomof said discharge opening, a concrete progressor for progressing the concrete mix into said elevating zone, and anelevating blade travelling through said zone for picking up and carrying concrete mix to the discharge passage and opening.

l1.` In a concrete mixer, a stationary mixing tank having an elevated discharge opening at one end thereof and including a recessed` Wall portion positioned above the discharge opening and leading to the discharge opening, means for elevating material into` said recessed wall portion, and a gate for the opening disposed in its closed position to form a continuation of said wall portion and to thereby re-direct material from said recessed wall portion back into the tank.

12. In a concrete mixer, a stationary mixing tank of generally cylindrical contour, spirally arranged mixing and' progressing blade means mounted for rotation within the tank to move the mixture therein into a discharge zone, said f blade means including a resilient edge portion for engaging the tank- Wall, a plurality of elevating devices travelling through the discharge `zone for lifting the concrete to an elevated point of discharge, said elevating devices extending in the direction of movement of the mixture through said tank and being mounted to operate closely with respect to the tank interior to thereby lift the concrete mixture to said point of discharge substantially intact without effecting appreciable separation or the ingredients of said mixture, and gate means at said elevated point of discharge.

13. In a concrete mixer of the type for use in transporting and mixing batches of concrete, a frame, a stationary mixing tank on said frame having a discharge opening at an elevated position in a wall structure of said tank and adjacent the rear of the frame, means providing a recessed discharge passage offset with respect to said wall structure and extending upwardly from the bottom of said discharge openings, means disposed within the tank for progressing concrete towards said wall structure, and concrete elevating means travelling through said tank adjacent said wall structure and past said discharge opening for elevating concrete along said wall structure to said recessed and offset discharge passage.

14. In a concrete mixer of the type for use in transporting and mixing batches of concrete, a frame, a stationary mixing tank on said frame having a discharge opening at an elevated position in a wall structure of said tank adjacent a rear corner thereof, means providing a recessed discharge passage offset with respect to said wall structure and extending upwardly from the bottom of said discharge openings, means disposed within the frame for progressing concrete towards said wall structure, and a concrete elevatin blade mounted in inclined relation to said wall structure and for operation close to the interior of said tank wall structure for elevating concrete mixture along said wall structure to said recessed and offset discharge passage without effecting undesirable separation of the ingredients of said mixture.

15. In a concrete mixer of the type for use in transporting and mixing batches of concrete, a frame, a stationary mixing tank on said frame having a discharge opening at an elevated position in a, wall structure of said tank and adjacent the rear of the frame, means providing a recessed afi-2am discharge passage offset with respect to said wall structure and extending upwardly from the bottom of said discharge opening, means disposed within the tank for progressing concrete mixture towards said wall structure, and a concrete elevating blade mounted for movement within said tank along a path extending upwardly past said recessed and offset discharge passage, said blade bearing an inclined relation to said wall structure to form a mixture retaining pocket therewith for elevation of concrete mixture along said path to said discharge opening.

16. In a concrete mixer of the type for use in transporting and mixing batches of concrete, a frame, a stationary mixing tank on said frame having a discharge opening at an elevated position in a wall structure of said tank and adjacent the rear of the frame, a spiral blade structure rotatably mounted in said tank for progressing material towards said wall structure, an elevating blade carried by said blade structure adjacent one end thereof and generally shaped to conform to the spiral of said blade structure and forming with said wall structure a pocket capable of retaining concrete mixture during elevation thereof for discharging the mixture from the tank.

17. In a concrete mixer of the type for use in transporting and. mixing batches of concrete, a stationary mixing tank having an elevated discharge opening adjacent one end thereof and including a recessed wall portion positioned above the discharge opening and leading to the discharge opening, means for elevating material into said recessed wall portion, and a gate for opening. Y

18. In a concrete mixer of the type for use in transporting and mixing batches of concrete, a stationary mixing tank of generally cylindrical contour, a spiral mixing and progressing blade mounted coaxially within the tank and disposed to move the material toward a wall structure thereof having a discharge opening at an elevated position thereon, a discharge ramp extending outwardly from said discharge opening, an offset portion of said wall structure extending upwardly from said opening t0 provide a discharge passage overlying a portion of said ramp, an elevating blade mounted for rotation with said spiral blade and disposed. to carry material upwardly to said discharge passage, and a gate for said opening.

the

ANTHONY G. ZICOVICH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 21,827 Erickson et al June 17, 1941 824,075 Gerner June 19, 1906 891,468 Dougan June 23, 1908 1,825,261 Burns et al Sept. 29, 1931 1,999,411 Haney Apr. 30, 1935 2,047,317 Esslen July 14, 1936 2,082,752 Lewis et al. June 1, 1937