TECHNICAL FIELD

The present invention relates to a portable compressor and a kit for repairing and inflating inflatable articles comprising said compressor.

BACKGROUND ART

One purpose of the present invention is to provide a portable compressor, meaning a compressor that can be transported without the use of trolleys or wheels, that is inexpensive, compact and easy to use.

This is particularly useful as part of a kit for repairing and inflating inflatable articles supplied in particular to inflate and repair tires.

The purpose of the present invention is achieved with a compressor as claimed in claim 1. BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to the accompanying drawings, illustrating some non-limiting embodiments thereof and referring:

- Figure 1: to a perspective view of a compressor according to the present invention;

- Figure 2: an exploded perspective view of figure 1. - Figure 3: a cross sectional view on a vertical plane along the line III-III in figure 1 ;

- Figure 4: an exploded perspective view of selected components of the compressor shown in figure 1. BEST MODE FOR CARRYING OUT THE INVENTION

In figure 1 denoted as a whole by reference numeral 1 is a portable compressor preferably for use in combination with a container of a sealant liquid to be injected into an inflatable article. The compressor 1 comprises an outer casing 2 having an air intake 3 and a control panel 4 having for example a screen of a pressure gauge 5 and one or more buttons 6, 7. Advantageously the button 6 starts/stops the compressor 1. The compressor 1 further comprises a tube 8 held by frictional force in a groove 9 defined by the outer casing 2 for example when the compressor is not in use. The tube 8 is connected to an inflatable article (not illustrated) and allows the latter to be inflated when the compressor 1 is started.

The compressor 1 further comprises (figure 2) an electric motor 10, preferably a direct current motor, housed within the outer casing 2, a pressure generator 11 driven by the electric motor 10 and a pneumatic relief valve 12 arranged downstream of the pressure generator 11. Preferably, the pressure generator 11 is a reciprocating pressure generator and comprises a speed reducer 13 connected to the electric motor 10, a connecting rod and crank mechanism 14 and a piston slidingly housed in a cylinder head 15. The cylinder head 15 defines the delivery side of the pressure generator 11 fluidically connected to the tube 8. The pneumatic relief valve 12 is arranged downstream of the delivery side of the pressure generator 11 so as to be able to adjust and in particular reduce the pressure inside the tube 8 when the latter is pressurized and connected to the inflatable article. The compressor 1 further comprises a pressure gauge having the screen 5 and connected to the tube 8 downstream of the delivery side of the pressure generator 11 to allow a user to adjust the pressure of the inflatable article by operating the compressor 1 to increase the pressure and by opening the relief valve 12 using the button 7 to reduce the pressure.

The compressor 1 further comprises an inner structure 16 on which the electric motor 10 and preferably also the pressure generator 11 and the relief valve 12 are mounted. The inner structure 16 has a peripheral portion 17 which defines the groove 9 in the outer casing 2. According to a preferred embodiment of the present invention, the inner structure 16 and the peripheral portion 17 are a single body, more specifically made of plastic material, and the outer casing 2 comprises a shell 18 which defines the air intake 3 and encloses the electric motor 10, the pressure generator 11 and the relief valve 12 with the inner structure 16 and the peripheral portion 17.

According to the present invention, on the opposite side of the electric motor 10 with respect to the inner structure 16, the compressor 1 comprises a retractor 19 for an electric cable 20 that supplies power to the electric motor 10. The retractor 19 is a spring retractor and comprises a reel 21 rotatable around an axis that is transverse, in particular perpendicular, with respect to an axis B of the electric motor 10. In this way the retractor

19 is alongside the electric motor 10 and the pressure generator 11 so that the compressor 1 is compact. For the same reason, the reel 21 is of the disc type so that the electric wire 20 can be wound either in a single turn having an increasing radius, as illustrated in figure 2, or so that the number of overlapping turns is equal to or more than the number of turns side by side along the axis A. By way of example in figure 2 the turns of the electric wire

20 overlap and there are no turns side by side. Turns that are arranged side by side have a substantially constant winding radius. The risk of the electric wire 20 getting tangled up during rewinding is thus reduced to a minimum. The retractor 19 further comprises a spring 22, preferably a band spring, arranged between the reel 21 and the inner structure 16 and preloaded so that the electric wire is maintained in a retracted condition for example as illustrated in figure 2. The band spring 22 has a portion 23 that is rigidly fixed to the reel 21 and a portion 24 that is fixed to the inner structure 16, a plurality of elastic coils being arranged between the portions 23, 24. The elastic coils are loaded when the electric wire 20 is unwound and are unloaded when the electric wire 20 is rewound .

The retractor 19 is enclosed in a shell 25 of the outer casing 2 so that when the electric wire 20 is rewound it is protected and/or concealed in an inner compartment 26 of the casing 2 defined by the shell 25 and by the inner structure 16. The compartment 26 protects the electric motor 10 from any contamination by dirt and/or debris that could become attached to the electric wire 20 when the latter is unwound outside the shell 25.

The retractor 19 further comprises a locking device 27 configured to lock the reel 21 in a desired angular position against the action of the spring 22 when the electric wire 20 is extracted by a length decided upon by the user. The locking device 27 is disconnected preferably manually to allow the electric wire 20 to be completely rewound. According to a preferred embodiment of the present invention, the locking device 27 is a ratchet gear and comprises a ring gear 28 preferably with asymmetrical teeth and a mobile pawl maintained in an engaged position with the ring gear 28 by means of a spring. When the electric wire 20 is extracted the ring gear 28 turns in relation to the pawl. When the user has pulled out the required length but the locking device 27 has been tripped through the action of the spring on the pawl, the angular position of the reel 21 is locked in the direction of winding by the pawl. When the user disconnects the locking device 27, in the example that is illustrated the user disengages the pawl manually by pressing a button, the reel 21 is released and wound up under the action of the spring 22.

The outer casing 2, more specifically the shell 25, defines a seat 29 (illustrated in negative in figure 2) to house and hold in place a power plug 30 connected to the electric wire 20. The electric wire 20 passes from the compartment 26 to the seat 29 through a door P in the outer casing, specifically in the shell 25. In the configuration in which the electric wire 20 is completely rewound, the latter is inside the compartment 26 and the plug 30 is outside the outer casing 2 (figure 4) .

The electric connection between the electric motor 10 and the electric wire 20 is made by brushing connections comprising fixed contacts 31, 32 respectively for the negative and the positive pole and mobile contacts 33, 34 carried by the reel 21. The fixed contacts 31, 32 are connected to the electric motor 10 and are carried by the inner structure 16 and the mobile contacts 33, 34 are connected to the electric wire 20 on the reel 21. The fixed contacts 31, 32 are preferably circular contacts and are electrically isolated from one another.

The rotation of the reel 21 is guided both radially and in the direction parallel to the axis A by means of sliding bearing surfaces. To reduce costs, the bearings are preferably exclusively sliding bearings to avoid the need for ball bearings.

According to a preferred embodiment of the present invention the reel 21 is radially guided by a sliding coupling comprising a pin 35 and a bushing 36. The pin 35 may be a single body or, according to the example of an embodiment in figure 2 and 4, a first portion 35' of the pin 35 is carried by the shell 25 and a second portion 35' ' of the pin 35 is carried by the inner structure 16. To prevent wobbling or swinging movements, the reel 21 comprises a guiding surface 37 which surrounds the spring 22 even in a non-continuous way. The guiding surface 37 is defined by a front shoe and is arranged on the opposite side of a recess 38 in the reel 21 on which the electric wire 20 is wound with respect to a wall 38 of the reel 21 that is transverse with respect to the axis A.

Figure 4 also illustrates an interlocking coupling to lock the portion 24 of the spring 22. Preferably the interlocking coupling comprises one or more projections 39 and the portion 24 is C-shaped to engage with the projection 39. To permit the correct winding of the coils of the spring 22, the portion 24 comes into contact with radial supports arranged along a curved or circular path around the axis A. According to the embodiment illustrated in figure 4, the radial supports have the same shape as the projection 39 so that the projections that are not engaged with the portion 24 act as radial supports.

The advantage of the compressor 1 according to the present invention is as follows.

The retractor simplifies the management of the electric wire, especially after its use.

Lastly it is clear that modifications and variations may be made to the compressor according to the present invention without departing from the scope of protection, as set forth in the appended claims.

To make it portable and, in particular, to make it suitable for repairing and inflating tires, the pressure generator 11 delivers a maximum pressure of 10 bar, preferably of 6 bar for light motor vehicles.

The outer casing may be made of a plastic material obtained by means of a pressing process.

The electric wire 20 and the plug 30 are suitable for transmitting direct electrical current and for being connected for example to the battery of a light motor vehicle, such as a car, or a heavy motor vehicle such as a van or lorry.

The compressor 1 as described herein may be used in combination with a container for a sealant liquid to be injected manually into an inflatable article, for example a tire .

The compressor 1 may be modified and comprise a releasable fluidic and mechanical connection to maintain the container of sealant liquid in a position for use and, at the same time in at least one configuration for use, fluidically connected to the delivery side of the pressure generator 11. The fluidic and mechanical connection may comprise a smaller seat to house an appendix of the sealant container or a larger and deeper seat to house the container in its entire height or in almost its entire height in the position for use. In both of these embodiments, the sealant liquid is injected by means of the pressure and/or flow of pressurized air generated by the pressure generator 11.

A fan 40 or other cooling system, preferably an air cooling system, is connected to the electric motor 10 to prevent overheating during use through the forced conduction of air inside the outer casing 2 through the air intakes 3.

According to the present embodiment the axis A is substantially vertical in the normal position in which the compressor is placed (figure 1) . It is possible, in particular when the compressor is used in combination with a container for a sealant liquid housed in a deep seat, for the retractor 19 to be on one side of the compressor and for the axis A to be substantially horizontal.