Thi-s invention refers to nozzles for industrial vacuum cleaners and relates more closely to a nozzle of a type which is fitted with disintegrating elements. These elements serve to disintegrate material sucked in through the mouth of the nozzle and prevent the nozzle and hoses or the like from becoming clogged.

Industrial vacuum cleaners are used in workshops and similar working premises for the purpose of removing dust and waste arising in the course of machining and processing from machines and the surrounding areas. The need for devices which effectively clean workshop premises is associated with the environmental problems caused by the waste that arises. V/aste strewn around machine tools and conveyors increases the risk of personnel slipping, gives rise to clogging of machines and on the whole creates an unpleasant working environment. Waste gives rise to a specific problem in the woodworking industry. Sawmills are extremely difficult to keep clean on account of the equipment such as conveyors, mechanical saws etc. installed on the premises. In connection with working in a sawmill trimming shop the risk is there¬ fore high that per-sonnel will suffer from "trimming shop sickness" largely due to inefficient cleaning of the premises.

This sickness is a form of allergy with the same symptoms as severe influenza. It is caused by fungi which grow on damp wood in poorly-ventilated environments. Handling the timber causes the spores from the fungi to swirl around in the air and they are subsequently inhaled into the lungs.

permanent injury in the form of reduced lung capacity. The only thing that helps in the long run is to change the environment or for the person concerned to change his employment. The development of devices which effectively remove these environmental problems is obviously a desirable goal.

The use of industrial vacuum cleaners for cleaning working premises is known. These consist either of central suction installations with outlets for the connection of suction hoses at suitable points in the premises or else of mobile equipment which is moved around the premises on wheels. In order to clean more effectively, these devices have exceptionally high suction power. However, when used in industrial premises where the waste consists of left-over endpieces, agglomera¬ tions of powder or other materials which have a tendency to clog the nozzles, such devices have not proved to be effective enough to clean the working premises satisfactorily.

In sav/mill premises the waste consists largely of splinters, chips and small pieces of wood which readily jam in nozzles and hoses, choking them and rendering them unservicable . Such obstructions must be removed from the nozzle or hose manually before cleaning can be resumed. As a result, cleaning work is time-consuming and often found to be so difficult that it is frequently neglected for this reason.

With the present invention a solution to the problem of clogged nozzles and hoses in industrial vacuum cleaners is proposed by providing the nozzle with an element which disintegrates the material sucked into it. More detailed characteristics of the invention will be evident from the following patent claims.

Per additional clari ication of the invention, a version of it will be described in the following with reference to the figures on the appended drawings .

Pig. 1 shows a perspective view of a nozzle.

3

Fig. 3 shows a nozzle as in Fig. 2 with the front part of the casing in the open position.

Fig. 4 shows a nozzle viewed from the front in the intake ^• direction.

A vacuum cleaner nozzle 1 is connected to a suction tube 2 on which an adjustable carrying handle 3 ^an< i a fixed handle 4 a e mounted. The unit thus' formed is designed to be connected via a suction hose to central vacuum cleaning outlets or to a portable vacuum cleaner.

Mozcle 1 consists of a casing of metal or other material at the intake mouth -of which is mounted a part 5 which pivots on a hinge 6. By tilting part 5 the suction opening of the nozzle can be varied.

Tilting of part 5 is achieved by means of an operating cylinder 7. one end of which is fixed to nozzle 1 and the piston of which is fixed to the pivoted part 5 •

Between the two side sections of pivoted part 5 i3 a rotatable shaft 3 (see Fig. 4) arranged transversely to the intake direction A. The •rotatable shaft is driven via. a transmission 9A by a reversible motor 9 arranged on pivoted part 5, which in the presented version consists of an air motor but electric motors, for example, can also be used. Arranged on shaft 8 and rotating with it are a number of disintegra- ting elements 10 positioned at a distance from each other, these devices pre erably consisting of milling cutters .

Nozzle 1 also contains a number of fixed knives 11 arranged behind the milling cutters 10, counted in the intake direction A. The fixed knives 11 are posi-tioned at a distance from each other in nozzle 1 5 so that each knife 11 occupies the space between two milling cutters 10. The edges of the knives 11 are at' ight angles to the rotatable shaft 8.

To control the tilting movement of part ----- "the direction of rotation of the milling cutters 10, a three-way valve 12 is arranged *-> under the carrying handle 4 o suction tube 2. Valve 12 is connected via hoses to the operating cylinder _. . the reversible motor 9 nd a compressed air source. To actuate valve 12 a spring-loaded sleeve 13

is arranged so as to slide on handle 4. By means of a control link 14 the sliding movement of sleeve 13 on handle 4 is transmitted to valve 12.

When using the nozzle unit, suction tube 2 is connected to a suction 5 hose. The operator grasps the adjustable handle 3 with one hand and the fixed handle 4 with the other hand. To regulate the tilt angle of part 5 and the direction of rotation of motor 9 _. the sleeve 13 s slid along handle 4« When the pivoted part 5 assumes the position shown in Fig. 2 the milling cutters 10 rotate in such a manner that 0 the vacuumed material is carried towards the rear knives 11, i.e. clockwise as shown in the Figure. When the vacuumed material consists of chips, splinters and small pieces of wood which tend to clog the nozzle it is disintegrated by the milling cutters 10 working against the knives 11.

5 The position of the pivoted part 5 shown in Fig. is a rest position in which the milling cutters 10 do not rotate. Sleeve 3 is spring-loaded on the handle in such a manner that it normally assumes this position. In this way, inadvertent starting of the milling cutters is avoided.

0 In an additional position (not.shown), part 5 has been tilted still further upward in the direction of arrow 3 (Fig. 3) • In this position the milling cutters are caused to rotate in the opposite direction to that described in connection with Fig. 2. As a result, the material that has jammed in the nozzle is caused to be carried out of it again.

5 Under certain circumstances it may be suitable to fit the nozzle with wheels to facilitate its use. Two wheels can be arranged beside the intake opening on a nozzle which is 300 mm wide, and a castor can be mounted behind these wheels.

Introductorily it was mentioned that the invention can be used for *J cleaning in sav__ill premises. However, the invention is not limited to this application only but can be used in connection with numerous spheres of activity. In conjunction with the manu cturε of float glass, for exaπple, waste occurs in the form of comparatively large pieces of glass. These r_ust be cleared away from floors and machi_r__

to avoid injuries to personnel. By using a vacuum cleaner nozzle with disintegrating elements, such waste can also be removed by means of industrial vacuum cleaners.

In connection with the casting of gearbox housings, etc. in foundries, the foundry sand is flushed out of the mould and collected in containers. The waste arising consists of a comparatively tough product of foundry sand and water glass . Removal of this material by vacuuming will be facilitated to a high degree if it is disintegrated by means of a nozzle according to the invention,

A nozzle according to the invention can be used for cleaning epoxy-treated concrete floors, for example, in which case the milling cutters can suitably be replaced by swivels of known ty e.

The aforementioned applications of the invention comprise only seme examples of its usefulness.

A nozzle according to the invention is on the whole practicable for vacuuming all materials which owing to their shape or consis¬ tency must be disintegrated before they can be sucked in through the nozzle .