SU973373A1 - Core of installation for moulding tubular articles of concrete mixes - Google Patents

Description

(54) CORNER OF INSTALLATIONS FOR FORMING TUBULAR PRODUCTS FROM CONCRETE OLESES

one

This invention relates to the precast concrete industry, namely the production of reinforced concrete pipes.

A device for forming tubes is known, comprising a mold and a vibrating core, having a rotational drive and a mechanism for vertical movement, provided with a movable frame and guides. The compaction of the concrete mix between the vibrating core and the form is made by the simultaneous action of vibration and pressure from the vibrating core. The pressure is obtained due to the profile curvilinear depression located on the vibrating core, which, when the vibrating core is rotated, has a wedging effect on the mixture between the vibrating core and the shape t}.

However, this device has a low quality of the molded product due to insufficient and unregulated specific pressure on the concrete mix, high power consumption of the vibratory core rotation drive due to the large contact area of the latter with the concrete mix and due to the vibrating core jamming during its rotation.

Closest to the present invention is a core of installations for forming tubular concrete products, containing a cylindrical body supported on it by means of an elastic gasket, a hollow head with a distribution cone and located in its cavity exciter in the form of a vertical drive shaft with a carrier in contact with it by means of at least one roller with the inner surface of the head, moreover, the elastic gasket is made in the form of a ring with protrusions on its inner side erhnosti 2.

The disadvantage of this core is

the duration of the process of compaction of concrete

15 mixtures, as well as poor quality products.

The purpose of the invention is to intensify the compaction process and improve the quality of the molded products due to polyfrequency vibrations.

This goal is achieved by the fact that the core of installations for forming tubular concrete products, comprising a cylindrical body supported on it by means of an elastic gasket, a hollow head with a distribution cone and

The exciter, located in its cavity, in the form of a vertical drive shaft with a carrier fixed on it, contacting at least one roller with the inner surface of the head, is provided with additional vibration exciters, one of which is made as adjustable in the case at the lower end of the drive shaft unbalances, and drove made vertically.

The drawing shows the proposed core of installations for forming tubular concrete products contains a cylindrical body 1, a hollow head 2 with a distribution cone 3, supported on a cylindrical body 1 by means of an elastic gasket 4. In the cavity of a hollow head is placed an oscillator made in the form of a drive shaft 5 with the carrier 6 fixed on it with the roller 7. The shaft 5 is connected to the distribution cone 3 by means of the universal joint 8. The carrier is placed on the shaft 5 movably with the possibility of movement in ol shaft 9 together with the support rollers 7. The carrier 6 has a fixing unit via a threaded connection 10. The lower end of the drive shaft 5 mounted perestavnye eccentric weight 11 capable of changing their position by means schlits 12 and threaded joint 13.

The drive shaft 5 is equipped with a support 14, placed on the brace 15 of the cylindrical housing 1. On the inner surface of the hollow head 2 is fixed an oscillation pathogen 16.

The core is located inside a fixed form 17.

The core of the unit for molding tubular concrete products works as follows.

The concrete mixture is fed into the space between the fixed form 17 and the core. The oscillation pathogen 16 is turned on, the mechanisms of rotation of the drive shaft 5 and the rise (not shown). The rotation of the drive shaft 5 is transmitted to the carrier 6. The eccentrically mounted roller 7, rolling without sliding along the inner surface of the hollow head 2, creates a radial pressure on the concrete mix due to the circular swing of the core around the axis of the drive shaft 5 with the angle of precession A. Rotating along with the drive shaft unbalances 11 cause disturbing force with the frequency of the drive shaft. The optimum ratio of the rotational frequencies of the drive shaft 4 and the vibration driver 16 is 1; 3.

Thus, the compaction of the concrete mix between the core and the form is simultaneously performed by the radial pressure from the oscillating core and the influence of two-frequency vibrations (one from the vibration oscillator 16, and the other due to unbalanced masses rotating together with the drive shaft). The inner surface of the pipe is smoothed using a cylindrical body 1.

Depending on the physicomechanical properties of the concrete mix and the required radial pressure, the eccentricity value of the vibrating core is controlled by moving the carrier together with the support 9 along the shaft 5 and fixed by means of a threaded joint 10.

The magnitude of the moment of mass of the unbalances 11 is controlled by changing their angular position on the slots 12, which is fixed by means of a threaded joint 13.

Due to the simultaneous effect of radial pressure and two-frequency vibration, the quality of the molded product is significantly improved: density, strength, quality of the inner surface of the pipe, etc. Hence, it is possible to use more rigid concrete mixtures with less cement consumption and less heat treatment.

The ability to control the vibrocord eccentricity and the mass moment of the unbalance gives the device versatility to different concrete mixtures, allows you to select the optimal value of the radial pressure and vibration parameters depending on the physical and mechanical properties of the material of the molded product.

In addition, the extraction of the vibrating heart at the end of the molding process is facilitated in view of the fact that the transverse size of the vibrating core is smaller than the internal diameter of the molded product.

Claims (2)

1. USSR author's certificate number 556037, cl. At 28 At 21/06, 1977. 2. USSR author's certificate for application number 2892790 / 29-33, cl. B 28 B 21/22, 1980.