Abstract:
Swivel connector for suction conduit of surface machining tools comprised of a first sleeve and a second sleeve that can be swivelled in relation to each other once assembled so as to set the respective longitudinal axes in at least two mutual angular positions, for example 0° and 90°, in order to favor more flexible operation of the tool in restricted spaces.

Description:
RELATED APPLICATION DATA 
       [0001]    This document claims priority from Italian Utility Model No. MI2007U000179, filed on May 11, 2007, which is incorporated by reference herein. 
       BACKGROUND 
       [0002]    The present invention relates to a swivel connector for connecting two lengths of a dust suction system for a surface machining tool. 
         [0003]    The problems caused by dust scattered in the environment by working tools are well known. The possibility of removing such dust by suction improves the tool operating conditions and also the operator&#39;s working conditions. Consider, by way of example, an orbital polisher without dust suction that operates in a closed environment. 
         [0004]    Notwithstanding the undeniable working advantages and presence in the prior art, the combination of a suction system and a tool may cause ergonomic problems due to the added encumbrance of the suction tube and the scant flexibility in deciding the positioning thereof. Indeed, the prior art connectors allow for placement of the suction tube in only one position, typically in a direction either perpendicular or parallel to the suction plane. 
         [0005]    A typical drawback of this arrangement lies in the reduced possibility of maneuvering the tool in the direction of the suction tube. Consider, by way of example only, an orbital polisher that has to operate in a cramped environment and the advantage of being able to have the suction tube outlet perpendicular to the work surface. Similarly, a polisher may be used to work between two closely spaced walls by advantageously exploiting a connector whose axis is parallel to the walls. It is evident that unless there is a possibility of shifting the direction of the suction tube connector, the polisher cannot work in both situations. 
       SUMMARY 
       [0006]    The object of the present invention is thus to overcome such disadvantages. 
         [0007]    According to the invention, this object is achieved by means of a swivel connector for suction systems coupled to machine tools. 
         [0008]    A connector according to the invention comprises two sleeves, mutually rotatable around an oblique swivel axis, oriented in particular at 45° in relation to the direction of suction, along the respective swivel plane normal thereto. The first sleeve connects to the suction hose and the second sleeve connects to the tool side, for the suction of particulate matter. Owing to the type of coupling between the two sleeves, the relative position of the respective axes may be selected as desired, and in a continuous fashion, so that the respective axes are either coincident or mutually inclined by 90°. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    These and other characteristics of the present invention will become apparent from the following detailed description of embodiments thereof, illustrated by way of a non-restrictive example in the appended drawings, in which: 
           [0010]      FIG. 1  shows a suction polisher with a connector according to the invention in the position with coincident axes; 
           [0011]      FIG. 2  shows the polisher of  FIG. 1  with the connector according to the invention in the position with the axes inclined by 90°; 
           [0012]      FIG. 3  shows a longitudinal sectional view of the connector according to the invention in the position with coincident axes; 
           [0013]      FIG. 4  shows a first sleeve of the connector according to the invention as viewed from below; 
           [0014]      FIG. 5  shows a longitudinal sectional view V-V of  FIG. 4 ; 
           [0015]      FIG. 6  shows a second sleeve of the connector according to the invention as viewed from above; 
           [0016]      FIG. 7  shows a longitudinal sectional view VII-VII of  FIG. 6 ; 
           [0017]      FIG. 8  shows the second sleeve of the connector according to the invention as viewed from the swivel plane; 
           [0018]      FIG. 9  shows the connector according to the invention where the second sleeve is built integrally with the polisher. 
           [0019]      FIG. 10  shows a longitudinal sectional view of another embodiment of the connector according to the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    The drawings illustrate a connector  50  according to the present invention, comprised of a first sleeve  1  and a second sleeve  2 . In  FIG. 1  it is possible to note a polisher  52  connected by means of the connector  50  and a swivel coupling  51  to a tube in turn connected to a suction machine. 
         [0021]    The first sleeve  1  is described with reference to  FIGS. 4 and 5 , where it is possible to distinguish a hollow cylindrical body  3  with one free end  4  for connection with a suction machine and one swivel end  5 . The swivel end  5  is formed by a cylindrical projection  6  terminating in a ring-shaped portion  7  that is broader in diameter than the cylindrical part  6  and narrows in diameter in the terminal part. The axis of the swivel end  5  is oriented, in this purely illustrative non-restrictive example, at 45° in relation to the axis of the cylindrical section  3  of the first sleeve  1 . A further characteristic of the cylindrical projection  6  and of the ring-shaped portion  7  is that of having pairs of notches  8  arranged along the diameters of the cylindrical part and which separate the cylindrical part  6  and the ring-shaped portion  7  into quadrants for the dual purpose of increasing the flexibility of the swivel end  5 , which will have to engage with a corresponding cavity on the second sleeve, and of enabling the operation of relative rotation between the sleeves to be achieved simply by overcoming a locking torque caused by the engagement of the notches  8  with corresponding projections on the second sleeve, as will become more apparent below. 
         [0022]    The second sleeve  2  is described with reference to  FIGS. 6 ,  7  and  8 . It is possible to distinguish a hollow cylindrical body  9  with one free end  10  for connection with a machine tool and a swivel end  11 . The swivel end  11  comprises a tapered hole  12 , whose diameter narrows inwardly and is such that the cylindrical projection  6  and the ring-shaped portion  7  can be pushed into it for assembly, and which has at least one pair of projections  13 , said projections  13  having dimensions such as to slightly reduce the diameter, and hence opening size of the tapered hole  12 . The projections  13  of the second sleeve engage with the corresponding notches  8  of the first sleeve so as to enable the operation of relative rotation between the sleeves to be achieved simply with a light push and thus prevent free, uncontrolled rotation, for example while the machine it is fitted to is working. A further fundamental characteristic of the swivel end  11  is that the axis of the swivel end is oriented, in this purely illustrative non-restrictive example, at 45° in relation to the axis of the hollow cylindrical body  9  of the first sleeve  1 . 
         [0023]    At the time of assembly, the cylindrical part  6  and the ring-shaped portion  7  of the first sleeve  1  are pushed into the tapered hole  12  of the second sleeve  2 , care being taken to match up the projections  13  and notches  8 . The two axes of the swivel ends  5  and  11  will thus coincide to form a single swivel axis  14  and the first sleeve  1  and second sleeve  2  will be coupled together along a swivel plane  53  that is inclined in relation to the axes of the two sleeves and perpendicular to the swivel axis  14 . The projections  13  are advantageously placed according to a diametrical axis, as it appears clearly, for example, in  FIGS. 6 and 8 , and the notches  8  are in turn placed according to two diametrical axes perpendicular to each other, as appears clearly in  FIG. 4 , so as to create temporary locks in the two working positions: with the sleeve axes parallel and with the axes perpendicular, according to the object of the present invention. 
         [0024]    If desired, additional working positions may be provided for, at angles other than 0° and 90°, using suitable locking elements to be applied in the two sleeves  1  and  2 . 
         [0025]    Moreover, in a further embodiment, the sleeve  2  may be built integrally with the tool  52 . 
         [0026]      FIG. 10  shows another embodiment of the connector according to the invention, in which the first and second sleeves  1  and  2  have respective hollow cylindrical bodies  3  and  9  with identical free ends  4  and  10  in which respective bushings  21  and  22  of the same or different diameter are rotatably housed. The connector  50  is thus rotatably connectable to a suction machine and a machine tool.