RU2602030C1 - Shf-drying chamber with circular waveguides - Google Patents

Abstract

FIELD: wood-working industry.

SUBSTANCE: invention relates to equipment for drying large-sized timber and can be used in forest and wood-working industries for drying of rounded and construction of logs, sawn bars, in making log houses. Drying chamber consists of fixed horizontally on the frame of the cylindrical casing with ring-shaped waveguides for microwave fields from two-step magnetrons and tubes with condensate drain for moisture removal from the body, cover with the end face of housing for loading into timber. Waveguides have approximately the magnetron swinging screens for providing of pulsation of the microwave field, are arranged along the length of the housing and turned relative to each other at a certain angle, ensuring absence of concentration of the microwave field in timber and charring. Positive effect is achieved by pulsation (change in value) of the microwave field and variable relative to timber its direction, secured by turning the waveguides relative to each other along the circumference of the body.

EFFECT: invention shall ensure higher efficiency, reliability, quality of drying timber and reducing of drying time.

1 cl, 3 dwg

Description

The invention relates to forestry and woodworking industries and is intended for drying large-sized round timber, mainly logs.

Known microwave installation for drying lumber (RU 2221974 C2, 01/20/2004), containing a horizontal cylindrical body with sources of microwave energy, inside which is a device for attaching lumber.

The main disadvantage of the installation is its unsuitability for drying large lumber, for example, round logs, due to carbonization of the wood before the drying of the logs to a predetermined moisture level, caused by the concentration of microwave energy along the axis of round timber.

The closest in technological essence is a microwave vacuum chamber for drying logs (RU 2011128515106 C2, 07/08/2011), which contains a cylindrical body with waveguides for microwave energy, nozzles for connecting a compressor and rotary drive sections located on the support rollers.

The drawback of the dryer is the need for constant rotation of a large bundle of timber, which leads to an increase in the energy intensity of the entire drying process.

The technical result is to reduce the energy intensity of the drying process of timber without reducing the quality of the wood.

The technical result is achieved by the fact that in the microwave drying chamber for logs and sawn timber, consisting of a cylindrical body with microwave devices located on it with waveguides mounted on a fixed frame and having an end cap for loading inside timber, according to the invention, the waveguides have an annular form, are located outside across the camera body and are rotated relative to each other at a certain angle, open and close by swinging screens installed inside the waveguides.

The invention is illustrated by drawings, where in FIG. 1 shows a device on the side, FIG. 2 is a sectional view of the device in the plane of the waveguide; FIG. 3 - offset relative to each other of two adjacent waveguides.

The drying chamber consists of a cylindrical body 2 horizontally mounted horizontally on a fixed frame 1, which has ring waveguides for microwave energy 3 coming from two-stage magnetrons-4 distributed around the entire body contour, and pipes for connecting steam traps to remove moisture from the camera body ( not shown in the diagram). And there is a cover 5 on one end of the case for loading timber. All waveguides have the same design. At the beginning of the waveguide, a magnetron 4 is installed to create a microwave field, behind which a swinging screen 6 is placed to close and open the waveguide and create a pulsation of the microwave field. The waveguide has several outputs 7 for directing the microwave field inside the housing to the timber along a curved path. With a standard length of timber of 6 m, the number of waveguides in length is 9 pieces. The zones of microwave fields of adjacent waveguides overlap, which eliminates the possibility of the appearance of untreated sections of timber. In addition, the waveguides are circumferentially offset relative to each other by 40 degrees, which eliminates the formation of zones of concentration of microwave fields and carbonization of wood.

Timber is fed into the chamber, the lid of the chamber closes, and the magnetrons are turned on. As timber is dried, moisture is collected by steam traps and discharged to the outside. After drying, the timber is unloaded from the chamber, the cycle is repeated again.

Claims (1)

Microwave drying chamber for logs and sawn timber, consisting of a cylindrical body with microwave devices located on it with waveguides, mounted on a fixed frame and having an end cover for loading inside timber, characterized in that the waveguides have an annular shape, are arranged across from the outside camera housings and are rotated relative to each other at a certain angle, open and close with swinging screens installed inside the waveguides.

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