Such an apparatus is described in US 4 765 367 and can be used to both refilling air into a car tyre and to mend a tyre puncture. The apparatus is a compact type that can either be carried as an accessory in a car, or mounted in the car without occupying much space.

The container with sealing material is provided separately and is connected to a selec- tor device, which consists of a valve arrangement. The valve has two positions, one of which compressed air is led to and though the container in order to conduct sealing material to the filling connector and thereby to the tyre, and another position where compressed air is led directly to the filling connector.

It is obvious that in practice the refilling function is by far the most used and it is rare that the function for mending a puncture is used. Nevertheless, the container with the sealing material, which constitutes a large part of the whole apparatus, must be carried all the time, among others because the encasing of the container in the apparatus pre- vents removal of the container.

Object of the invention It is a main object with the invention to provide an inflating unit, where it is not neces- sary to carry the container with the sealing material all the time.

Summary of the invention This is achieved with an inflation unit of the kind mentioned in the introduction, where the selector device is arranged for alternative fastening of the container or an insert, where the insert is attached to the selector device instead of the container with the sealing agent when delivering compressed air directly from the source of com- pressed air to the tyre, and where the insert is adapted so that it can lead compressed air directly from the source of compressed air to the filling connector.

When the the unit is usen for inflating, the insert is placed in the selector device, and inflating may be effected. When mending a puncture is needed, the insert is substuted with the container containing sealing agent, and mending may be performed. When not in use, the container can be stored somewhere and apart from the inflating unit, so that it is not needed to carried with the unit.

In a preferred embodiment of the invention, the container is provided with a neck, which can engage a socket in the inflating unit, for example by a screw connection, and where the socket comprises a perforation member for breaking a sealing in the neck of the container, where the perforation member consists of a sharp edged pipe connector provided as a part of the duct of compressed air and protruding into the socket, and where the insert has a recess or cavity for accommodating the pipe connec- tor and simultaneously allowing air to pass from the pipe connector to a downstream section of the air duct. When using the mending function, the container is just mounted in the socket, whereby the sealing is broken, and by introducing compressed air, the sealing material is forced out of the container.

To avoid sealing material to be driven in the direction of the source of compressed air because of a static pressure downstream of the container, it is preferred that in connec- tion with, and downstream of the pipe connector, a check valve is provided for pre- venting flow from the pipe connector and in the direction of the source of compressed air.

Brief description of the drawings Embodiments of the invention are described in detail below with reference to the drawings, where: Fig. 1 shows a front view of an inflating unit according to the invention, Fig. 2 shows an inflating unit according to Fig. 1, but where the upper cover is re- moved, Fig. 3 shows a section on the line Ill-Ill in Fig. 1 in a first embodiment of the inflat- ing unit according to the invention, and Fig. 4 shows the same section as Fig. 3, but of a second embodiment of the inflating unit according to the invention, and where a bottle with sealing material is mounted instead of a plug in the unit Detailed description of embodiments As shown on the drawings, according to the invention the inflating unit can be ar- ranged in a rectangular and relatively flat box or cabinet 1, which on its front is pro- vided with an electronic switch 2 and a manometer 3 which all the time detects the excess pressure in the duct of compressed air of the apparatus and the connected parts.

With the number 4 the outline of a container with sealing material is indicated, which can be a latex suspension or an other known sealing agent. In this case, the container 4 is provided in the shape of a bottle made of synthetic materials. Of course other ge- ometries and materials can be used for the container 4. The unit, as shown on Fig. 2, comprises an electric motor 5 with an output shaft 6, which by a crankshaft 7 operates a compressor piston 8. In this case, the motor 5 is a DC motor for 12 volt which with- out further ado can be connected to a plug for a cigarette lighter in a car, for example with a plug 9 on Fig. 2 connected with a not shown wire.

The compressed air compressor is constructed in a known manner, as the inlet valve is built into the piston 8 and the outlet valve in outlet 10 from the compressor. Thus out- let 10 forms the first section of the duct of compressed air, which extends from outlet 10 and forward to a tube 12 which, in a not shown way, is provided with a connector for connection to a valve on a tyre.

The apparatus is provided with a safety valve 13 and an air-escape valve 14 At the outlet 10 from the compressor, the compressed air duct is formed as an elbow pipe, which ends in a sleeve 15. Between sleeve 15 and tube 12 there is a intermediate piece 16, 16'constituting the essential part of the invention. The intermediate piece 16 is attached to the unit with two screws 17, see Fig. 2. In this embodiment of the inven- tion the intermediate piece 16, 16'is provided with a connection 18 for the container 4 in the form of a screw socket 18. At the centre of the socket 18, a pipe connector 19 protrudes, provided with a slanting cut 20 and a sharp upper edge 24. The pipe con- nector 19 is part of the duct of compressed air and communicates with the outlet 10.

Next to the pipe connector 19 the duct of compressed air continues at the bottom of the socket 18, here shown by the number 21.

When the inflating unit according to the invention is used for refilling a tyre, an insert or plug 22 is inserted into the socket 18. The plug 22 has an airtight abutment against the bottom of the socket 18 by means of a sealing ring 23. It can be seen on Fig. 3 that the plug in that way completely closes the admission of compressed air to the envi- ronment. The compressed air, which flows from the duct, passes into a cavity 25 in the plug 22, from where the air passes between the inner walls of the cavity 25 and the outer walls of the connector pipe 19 down to the continuation of the compressed air duct 21.

When the unit is used for mending a tyre, the plug 22 is unscrewed, and a bottle 4 with sealing material is screwed on, as the sharp upper edge 24 of connector 19 cuts though the film sealing which initially covers the opening of the bottle 4. In the same way as the plug 22, the opening of the bottle 4 is sealed with a sealing ring 23 in rela- tion to the bottom of the socket 18. By activating the compressor, compressed air is lead into the bottle 4 and the sealing material is pressed out through the duct piece 21 and out into the tube 12.

It is preferred to arrange the unit as shown on Fig. 4 with a intermediate piece 16' where a check valve 27 is disposed between the pipe connector 19 and the up-stream sections of the duct of compressed air. In its simplest embodiment, as shown on Fig. 4

the check valve consists of a ball 28, which in a closed position can fit into a small hole 29, while in an open position it is pressed up against a mesh 30, where air can pass around the ball 28 and into the pipe connector 19. Thereby it is avoided that a static pressure in the tube 12 and bottle 4 causes the sealing material to flow back to- wards the outlet 10 of the compressor.

The indicated use of a intermediate piece 16, 16'allows for separating the parts in order to clean the intermediate piece and adjoining parts for sealing material after hav- ing used the mending function.