RU2366572C2 - Device to form concrete articles - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: proposed device comprises forming table with supports, oscillation exciter with drive and crank pair articulated with aforesaid table, flexible element and mould arranged on the table and coupled therewith. Note here that the said mould features detachable bottom and at least two clamps, while forming table has at least three supports furnished with wheels, to of them being mounted aligned. Flexible element represents a cylindrical compression spring fitted into exciter crankpin. Exciter allows 1.0 to 2.5 Hz-oscillations of the said table with oscillation amplitude of 0.020 to 0.070 m. Crankpin consists of two axially moving parts articulated via flexible element.

EFFECT: higher quality of finished products.

12 cl, 16 dwg

Description

The invention relates to vibration devices for compaction of concrete products and can be used in construction, for example, in the construction of low-rise buildings from small-sized building stone, made, in particular, directly at the construction site.

A device for sealing building materials from hard mixtures, such as concrete (SU 278499, B28B 1/08, 1972). It is a resonant vibration pad containing a working body connected by means of elastic ties to a balancing frame in the form of a molding table with grippers that hold the shape. The frame is mounted on shock absorbers, equipped with buffer elements and a crank oscillator, which is connected to the working body by its connecting rod through an elastic element made in the form of two pairs of coaxial conical and cylindrical bushings. A disadvantage of the known device is its unstable work on compaction of the concrete mixture and the inability to adjust the parameters of the desired operating mode.

Known vibration platform for molding products from concrete mixtures (SU 531739, B28B 1/08, 1976). It is an improvement of the aforementioned vibration platform and is additionally equipped with a slider pivotally mounted on one of the ends of the working body (molding table) with a guide made rotatable relative to the transverse horizontal axis and mounted on the base, which intensifies the compaction of the concrete mixture due to the action of pendulum vibrations. The disadvantage of this device is the design complexity.

A device for concrete molding and a method of such molding are known (JP 2000141327, B28B 1/08, 2000). The method includes a low-frequency force action on a forming table mounted on elastic elements with a mold filled with concrete, providing a table close to horizontal reciprocating movement with a frequency of 1.5-4.0 Hz and an amplitude of 5-20 mm. The device that implements this method comprises a forming table mounted on four elastic struts capable of deflecting in vertical planes, a vibration exciter having a drive located in the loading zone and made in the form of a crank pair, kinematically connected to the forming table, forming a crank-balancing mechanism with it, and in the form of a container with a bottom form, removably connected with the molding table. This technical solution reduces cement leakage and the risk of vibration and noise with good molding quality. Its disadvantage is the presence of a vertical component of the vibrations, which leads to delamination of the concrete mix according to the density of the components.

The objective of the patented invention was to create such a device for molding concrete products, which, while maintaining vibration safety, allowed to improve the quality of the product by the uniform distribution of the components of the concrete mixture by eliminating the vertical power component of vibrations and ease of use when used directly in the construction zone of low-rise buildings.

To solve the problem with obtaining the specified technical result, a patented device for molding concrete products, for example, small-sized stone, includes a molding table with supports, an excitation oscillator having a drive located on the site in the loading zone and a crank pair kinematically connected to the molding table, elastic element and placed on the molding table and removably associated form. A distinctive feature of the device is that the form is made with a removable bottom in the form of a pallet and is equipped with at least two clamps, the molding table has at least three supports that are equipped with wheels, two of which are mounted coaxially, and the elastic element made in the form of a cylindrical compression spring and integrated into the connecting rod of the vibration exciter, which provides vibration of the molding table with a frequency in the range of 1.0-2.5 Hz and amplitude in the range of 0.020-0.070 m, and the connecting rod is made of two axially movable parts, kinematically closed through this elastic element, the butt ends of the connecting rod have helical grooves that mesh with the end sections of the compression spring, and the connecting part of the connecting rod of the vibration exciter is detachably connected to the molding table on the side of the supports with coaxial wheels.

For the possibility of independence of the transmission of force or regulation, the connecting rod of the device is made tubular, in the gutter cavities of which there is a guide sleeve rigidly connected to one of the ends of the connecting rod, and is additionally equipped with a tension spring placed in the guide sleeve and fixed by its ends in the butt ends of the connecting rod with the possibility of tension control .

To be able to adjust the operating modes of the device with the necessary characteristics, the crank of its oscillation pathogen is equipped with a counterweight and is made in the form of a disk with a radial groove in which a slider pivotally connected to the connecting rod is mounted with the possibility of fixation at a given eccentricity.

For the possibility and convenience of transporting the product to the unloading zone while maintaining the possibility of forming the product, the support with the non-coaxial wheel of the molding table of the device is rotatable with the possibility of fixing in the parallel position of the axles of the wheels and is equipped with a handle that interacts with the bracket of the molding table only in the lower (non-transport) position.

To preserve the constancy of the composition of the concrete mortar by eliminating the flow of water out of it without imposing strict requirements on the accuracy of the manufacture of contacting surfaces and improving the quality of the surface of the product, the device is equipped with a separator between the form and the pallet made of easily deformable and non-adhesive material to the cement component of the concrete (polyethylene sheet with a thickness of 0.003- 0.008 m or sheet rubber of the same thickness, or in combination with an additional plastic film in case of attaching new separator to the pallet) and a clamp in the form of two threaded rods interacting with the handles screwed into the pallet, connected by folding bolts and nuts to the base plate of the molding table.

To exclude possible lateral displacement of the molding table during its vibration, the device is equipped with wheel guides located on the site in the loading zone.

The invention is illustrated by drawings, which depict:

figure 1 a device for molding concrete products, such as small-sized building stone, front view with a partial section (in the position before concrete supply);

figure 2 is the same, a section aa in figure 1;

figure 3 is the same, step section bB in figure 1;

figure 4-6 is the same, a modification of its elastic element, a longitudinal section;

Fig.7 is the same, part of a cross section of a modification of the pallet;

on Fig-15 - the same, different phases of its operation;

in Fig.16 is the same, a graph of the averaged dependence of the required amplitude of the oscillations of the molding table on its frequency during vibration exposure to the concrete mixture in the mold.

A device for molding concrete products (Figs. 1 and 2) includes a molding table 1, a vibration exciter 2 with a drive 3, an elastic element 4, and a mold 5.

The molding table 1 is made in the form of a plate 6 having a working flat surface 7 and at least three bearings 8, 9 and 10, equipped with the same wheels 11, 12 and 13, respectively, and the axles 14 and 15 of the wheels 11 and 12 are mounted coaxially, their supports 8 and 9 are rigidly connected to the plate 6, and the support 10, the bearing axis 16 of the wheel 13, is rotatable, its axis of rotation 17 is perpendicular to the working surface 7 of the plate 6 and placed in the bearing 18 of the latter.

The molding table 1 is equipped with a handle 19 in the form of a rod 20 having a handle 21 at one end and a fork 22 at the other end, the ends of which 23 are connected to the axis 16 of the wheel 13 of the pivot bearing 10, forming a hinge 24. To hold the handle 19 in the lower position ( during compaction), ensuring that the axis 16 of the wheel 13 is oriented parallel to the coaxial axes 14 and 15 of the wheels 11 and 12, a bracket 25 is mounted on the plate 6 of the molding table 1 in front of the bearing 18, made in the form of a plate with a hook-shaped end 26 with the possibility of interaction with the base 27 of the fork 22 , i.e. gearing in the lower position and out of gearing in the raised (transport) position of the handle 19.

The causative agent of oscillations 2 (Fig. 1) has a crank pair, the connecting rod 28 of which is connected via a quick-release joint 29 to the plate 6 of the molding table 1, and the crank 30 is made in the form of a disk with a radial groove 31, in which a hinge connected to the connecting rod 28 is placed 32 slider 33 with the possibility of fixing at a given eccentricity (to adjust the size of the amplitude of the oscillations). For this, the crank 30 is provided with a screw 30a located along the radial groove 31. The screw 30a has an annular groove 30b (Fig. 3), through which two screws 30b, which are screwed into the crank 30 and are symmetrically positioned, are screwed into the crank 30, forms a screw connection 33a with the slider 33 and is equipped with a lock nut ( not shown in the drawing).

The connecting rod 28 is made of two longitudinally movable parts 28a and 28b (FIG. 1) kinematically closed through an elastic element 4.

The elastic element 4 can be made in the form of a cylindrical compression spring 34 (Fig. 4), and the butt ends of the parts 28a and 28b of the connecting rod 28 have helical grooves 35 that engage with the end parts 34a and 34b of the compression spring 34. The connecting rod 28 can be made tubular with a cavity 36. In the connecting cavities 36a and 36b of the connecting rod 28 (Fig. 5), a guide sleeve 37 can be placed rigidly connected, for example, by means of a screw 38, to one of the end parts, for example, 28a of the connecting rod 28, which eliminates lateral direction oscillations with insufficient rigidity of the compression spring i am 34.

A modification of the execution of the elastic element 4 is possible, which is further provided with a tension spring 39 (Fig. 6) located in the guide sleeve 37. The spring 39 is connected with its connecting ends 39a and 39b, respectively, with the pin 40 in the guide sleeve 37 and the connecting rod located in the connecting rod part 28b 28 by a screw element 29a of a quick-release joint 29 with the possibility of adjusting the tension, for example, by means of a screw 38 and several holes 41 made in the guide sleeve 37 (discrete adjustment), and by means of a screw Macaws - screw element 29A and nut 42 (smooth adjustment). The screw element 29a on the inner end protrusion 43 has an opening 44 for passing the end 39b of the spring 39, and on the outer end protrusion 45 there is an opening 46 for the spring-loaded locking pin 47 of the quick-release joint 29. Within its external thread 48, the screw element 29a has a longitudinal groove 49, which includes the end of the screw 50, fixed in part 28b of the connecting rod 28, which prevents the rotational movement of the screw element 29a during rotation of the nut 42 and maintains translational. The nut 42 is made with an outer annular groove 51 on the connecting rod 28 of its part 42a entering the cavity 36. The axial displacement of the nut 42 during its rotation is prevented by the presence in its annular groove 51 of the end of the screw 52, fixed in part 28b of the connecting rod 28.

The crank 30 of the vibration exciter 2 is mounted on the shaft 53 of the actuator 3 (Fig. 1), for example, an electric gearbox, and can be equipped with a counterweight 54 of the necessary mass and eccentricity of the installation.

Form 5 (FIGS. 1 and 2) is made removable in the form of a rectangular cross-section of the container 55 open from the ends, equipped with a removable tray 56 and two clamps 57.

The pallet 56 is made in the form of a rigid rectangular plate having an upper working surface 58 with dimensions exceeding the transverse dimensions of the container 55. A separator 60 is arranged between the lower end face 59 of the form 5 and the upper surface 58 of the pallet 56, made of material that is easily deformable and non-adhesive to the cementitious component, for example, from sheet polyethylene with a thickness of 0.003-0.008 m or from sheet rubber of the same thickness. The sheet separator 60 can be fixed on the upper surface 58 of the pallet 56 using screws 61 (Fig.7) or glue (not shown); in this case, it is possible to use an additional film polyethylene separator 60a, superimposed on the main separator 60, and the latter serves as a flexible lining, which eliminates the possibility of water leakage from the concrete-filled mold due to the guaranteed contact of the mold end face 59 with the separator 60a when forming the mixture. The presence of an additional film separator 60a facilitates the removal operation from the pallet 56 of the finished product.

Each of the two clamps 57 (FIGS. 1 and 2) is made in the form of a rod 62 having a thread 63 on one (lower) end, screwed into the threaded hole 64 of the thickening 65 of the pallet 56, and on the other - a handle 66. The rod 62 passes through the opening 67 of the brace-shaped handle 68 of the mold 5. In the middle part of the rod 62, two stops 69 and 70 are made, between which there is a plate 71 having a stiffener 72 and a hole 73 through which the rod 62 passes. The plate 71 rests on the brace-shaped handle 68 of the form 5 when pressed the latter to the pallet 56 through the separator 60, and when removing the clip 57 remains on its rod 62, held by stops 69 and 70.

The pallet 56 is attached to the plate 6 of the molding table 1 using two pairs of hinged bolts 75 provided with nuts 74, connected by hinges 76 to the brackets 77 of the plate 6 and included in the slots 78 of the latter which are open from the ends (FIGS. 1 and 2).

To establish the operational parameters of the vibration effect (amplitude A, frequency f and time t) on the concrete compaction, experiments were carried out on an experimental sample representing one of the possible modifications of the proposed device with a frequency-controlled drive of oscillation exciter with the following initial data:

1) two steel forms were used, which ensured the receipt of two series of standard-sized stones (length, width, height)

390 × 190 × 188 mm and 288 × 138 × 138 mm, respectively;

2) a concrete mixture of the composition was prepared:

expanded clay gravel (K) with a maximum grain size of 40 mm;

sand (P) fine-grained river;

Portland cement (C) grade 400;

tap water

when the ratio of components in volume fractions

K: P: C = 6.5: 3.5: 1.

In this case, water was approximately 3 volume fractions in order to obtain the consistency of the concrete mixture corresponding to the beginning of the zone of hard mixtures bordering the zone of plastic mixtures, the mobility of which was estimated from the cone settlement. The transition from a plastic mixture to a rigid mixture was characterized by a change in the size of the cone precipitation from 1 cm to zero. For concrete mixtures used in the experiment, using the inventive device (its modification with a variable speed drive), their conditional stiffness was determined, determined by the vibration time (in seconds) necessary for molding the concrete mixture in the mold. The actual conditional stiffness of the used concrete mixtures varied from 5 to 15 seconds.

The experimental data shown in the graph (Fig. 16) express the average relationship between the optimal combinations of amplitudes A (in mm) of the vibration effect on the concrete mix and the frequency of the action f (in Hz) in the ranges A = 20-70 mm = 0.020-0.070 m, f = 1.0-2.5 Hz when reaching the end of the formation of light concrete in a time in the range of 5-15 s for concrete with mixtures with a conditional hardness of about 10 s.

The above graph makes it possible to simplify the experimental setup of the operating modes of the pathogen in each specific case, depending, for example, on the size of the form and composition of the concrete mix.

The operation of the patented device can be represented using a modification that includes a three-wheeled molding table, an elastic element in the form of a combination of two springs (compression and tension) and a sheet of polyethylene separator.

In the loading zone on the platform with a rigid base 79 (Fig. 1), a drive 3 is permanently installed with a crank pair 2 and the latter is connected using a quick disconnect hinge 29 with a forming table 1, the wheels 11, 12 and 13 of which rest directly on the base 79 or interact with guides 79a, 79b and 79c fixed on it, respectively, which are made in the form of, for example, channels, planks or corners. Lay on the plate 6 of the molding table 1 a pallet 56 with a separator 60, install it on the last mold 5 with its subsequent fixation with the help of clamps 57, and the pallet 56 - to the plate 6 with the help of hinged bolts 74 and nuts 75. After that, the necessary operating mode is set - frequency for the drive 3 and amplitude for the vibration exciter 2 (by moving the slider 33 by rotating the screw 33a to the required eccentricity size and adjusting the necessary initial deformation of the elastic element by rotating the nut 29a). The necessary operating mode is set up once for the manufacture of a specific type of concrete product (building stone according to its dimensions and composition of the components of the source material). Then, a dosage portion 80 of concrete mixture 81 prepared in advance in a concrete mixer is fed into mold 5, and after leveling of the upper layer, drive 3 is turned on for a predetermined time, subjecting the concrete mixture 81 to vibration (Fig. 9). The drive 3 is turned off, the crank pair 2 is disconnected using the quick disconnect hinge 29 from the forming table 1 (Fig. 10), by turning the handle 19 is disengaged from the bracket 25, i.e. the base 27 of the fork 22 with the hooked end 26 of the bracket 25 (FIG. 1), and transporting the mold 5 with molded concrete mixture 81a by moving the molding table 1 into the curing zone of the product. In the curing zone of the product (Fig. 11), the pallet 56 of the mold 5 is removed from its connection with the plate 6, the mold 5 is removed together with the separator 60 and the pallet 56 and placed on a horizontal surface 82. A new pallet 56a is installed on the plate 6 of the molding table 1, fixing it with the help of hinged bolts 74 and nuts 75 and impose a new spacer 60b on it (Fig. 12). Then the clamps 57 are removed, the mold 5 is removed from the raw product 83 (FIG. 13), the mold 5 is mounted on the separator 60b, fixing it on the new pallet 56a by the clamps 57 (FIG. 14), and the molding table 1 is delivered to the concrete loading zone (FIG. .one). Next, the technological cycle for molding the next concrete product is repeated. After each previously formed article 83a reaches the required strength, it is removed from the pallet 56 together with the separator 60, and then the separator 60 is separated from the product 83a by gradual tearing (Fig. 15).

The use of the invention extends the range of means for molding concrete products, especially in the form of small-sized building stone with the possibility of their production directly on the construction sites of low-rise buildings.

Claims (12)

1. A device for molding concrete products, including a molding table with supports, an exciter of vibration, having a drive located on the site in the loading zone and a crank pair kinematically connected to the molding table, an elastic element and placed on the molding table and removably associated with it characterized in that the mold is made with a removable bottom in the form of a pallet and is equipped with at least two clamps, the molding table has at least three supports, which are equipped with wheels, two of which are coaxial but, and the elastic element is made in the form of a cylindrical compression spring and is integrated into the connecting rod of the vibration exciter, which provides vibration of the molding table with a frequency in the range of 1.0-2.5 Hz and amplitude in the range of 0.020-0.070 m, the connecting rod is made of two movable axial the direction of the parts kinematically closed through this elastic element, the butt ends of the connecting rod have helical grooves that engage with the end sections of the compression spring, and the connecting part of the connecting rod of the vibration exciter is detachably connected to the molding table from the sides Bearings with coaxial wheels. 2. The device according to claim 1, characterized in that its connecting rod is made tubular, in the connecting cavities of which there is a guide sleeve rigidly connected to one of the ends of the connecting rod, and is additionally equipped with a tension spring located in the guide sleeve and fixed at its butt ends connecting rod with adjustable tension. 3. The device according to claim 1, characterized in that the crank of its oscillation pathogen is made in the form of a disk with a radial groove, in which a slider pivotally connected to the connecting rod is mounted with the possibility of fixation at a given eccentricity. 4. The device according to claim 1, characterized in that the crank of its oscillation pathogen is equipped with a counterweight. 5. The device according to claim 1, characterized in that the support with an off-axis wheel of its molding table is connected to the plate of the latter with the possibility of rotation around an axis perpendicular to it and fixing in a parallel position of the axles of the wheels. 6. The device according to claim 5, characterized in that the molding table is equipped with a handle in the form of a fork, the ends of which are pivotally connected to the ends of the wheel axis of the pivot bearing, and a bracket with a hook-shaped end mounted on the plate, and with its base the fork engages with a hook-shaped end the bracket in the lower position of the handle with the possibility of disengagement in the upper transport position, and the kinematic connection of the connecting part of the connecting rod of the pathogen to the forming table is carried out from the side of supports with GOVERNMENTAL wheels and is designed as a quick joint. 7. The device according to claim 1, characterized in that it is equipped with a separator located between the lower end of the mold and the upper surface of the pallet and made of easily deformable and non-adhesive material to the cementitious component of concrete. 8. The device according to claim 7, characterized in that the separator is made of sheet polyethylene with a thickness of 0.003-0.008 m 9. The device according to claim 7, characterized in that the separator is made of sheet rubber with a thickness of 0.003-0.008 m 10. The device according to claim 8 or 9, characterized in that it is equipped with an additional separator made of plastic film, and the main separator is mounted on the upper surface of the pallet. 11. The device according to claim 1, characterized in that its shape is equipped with two staple-shaped handles, each of the form clamps is made in the form of a rod having a handle, forming a threaded connection with a pallet, which is detachably connected to the molding table plate using at least one pair of hinged bolts with nuts, the rod passing through the opening of the staple-shaped handle, two stops are made in the middle part of the rod, between which there is a plate having a hole through which the rod passes and resting on the bracket the knob of the form. 12. The device according to claim 1, characterized in that it is equipped with guides for wheels of the supports of the molding table mounted on the site in the loading zone.

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