PORTABLE ELECTRICAL MILLING AND/OR TRIMMING MACHINE TOOL FOR THE MACHINING WITH SUCTION OF PRODUCED CHIPS AND DUST

Abstract: Portable electrical milling and/or trimming machine tool for the machining of a material with the production of chips and/or dust, comprising a body (1,5,9) encasing a vertical-axis electrical motor (21) for the actuation of the tool (18), provided with a gripping handle (33) and slidingly mounted by means of a guide system (20, 12) relatively to a support plate (7) provided with a central aperture (26) for the passage of the tool (18), said machine incorporating a suction system for said chips and said dust, comprising in said supporting plate (7) at least a duct (29) communicating on one side with suction opening (27) coming in correspondence of said plate central opening (26), and on the other side with a duct (30) concentrically formed around said guide system by a bellows sleeve (6) surrounding this guide system (20, 12), this latter duct (30) being in its turn in communi­ cation, through channels provided inside the actuating motor enclosing body (5), with a tubular discharge element (4) inte­ grated inside the gripping handle (33), and ending with a connec­ tor (3).

Description: Disclosure The object of the present invention is a Portable electric milling and/or trimming machine tool for the machining with the suction of the chips and of the dust produced during the machining of wood, plastic material and/ or fiberglass. Tool machines of this type are known, which substantially comprise a body enclosing a vertical-axis electrical motor provided with a gripping handle, and slidingly assembled by means of a guide system relatively to a supporting plate provided with a central aperture for the passage of the tool actuated by the electrical motor. The guide system is constituted by at least a tube acting as a vertical guide and support, fastened onto the supporting plate onto which said body can slide by means of guide sleeves. Whilst on resting the body containing the tool actuat ing motor is lifted, so that the tool rests above the supporting plate, during the machining operation the support ing plate is placed on the piece to be machined and the operator, by acting on the gripping handle, lets down the body encasing the motor, so that the tool, by penetrating through the aperture provided in the supporting plate comes to act on the piece. During the machining chips and dust of material are clearly formed, which disturb the visibility of the surface of the piece under machining. In order to obviate this drawback, it could be used the motor cooling air suit ably directed and/or conveyed towards the surface being machined. This caused the dispersion of dust within the working premises, notably disturbing the operator. To obviate mh a drawback, suction means could be used such as hoods or flexible sleeves which did not solve completely solve the problem, or at least created an inconvenience for the operator just in the working area. It is moreover known that the portable electrical machine tools use various systems to allow either plunging operations or operations in fixed positions to be obtained. One of such systems uses a locking-screw device directly acting on the rods of a support; such a system ren ders laborious the adjustment operations and on the other side does not allow the control of the depth, if the tool machine is used for plunging operations, once that the lock ing screws have been released. Other types of tool machines are equipped with sliding external accessories, provided with guides and/or shoulder elements, which, even though they allow machinings of a certain precision to be carried out, require long and laborious assembling and positioning as well as adjustment operations. Still another system envisages the use of supporting threaded rods, at least partly provided with micrometric adjustment means, manually actuated by thumbscrews. Such devices, even if they can be initially easily adjusted, by being unprovided with locking systems, can undergo accidental variations of the adjustments, essentially due to the vibrations caused by running machine tool. It is moreover important to note that such a system does not allow plung ing machining operations, in that the tool is rigidly link ed to the supporting rods of the machine tool through said screw device. A purpose of the present invention is to provide a ma chine tool of the above-indicated type provided with a system for sucking the chips and the dust produced by the machining totally provided inside the machine, hence eliminating any external components. A further purpose of the present invention is that the said tool machine be provided with an adjustment system which allows plunging operations to be carried out with the possibility of a quick and precise adjustment of the stroke, and at the same time allows machining operations to be effected in selected fixed positions. It must moreover be such as to allow an operator to perform easy and fast manoeuvres both for the adjustment and for the selection of the machining function, without that it be necessary it to modify by means of external fittings or the like the configuration of the machine tool, or it to intervene on the supports thereof. These and further purposes according to the present invention are achieved by accomplishing a portable electric al milling and/or trimming machine tool for the machining of material with the production of chips and/or dust, comprising a body encasing a vertical-axis electrical motor for the actuation of the tool, provided with a gripping handle and slidingly mounted by means of a guide system relatively to a support plate provided with a central aperture for the passage of the tool, characterized in that said machine incorporates a suction system for said chips and said dust comprising in said supporting plate at least a duct communicating on one side with suction openings coming in correspondence of said plate central aperture and on the other side with a duct concentrically formed around said guide system by a bellows sleeve surrounding this guide system,this latter duct being in its turn communicating, via channels provided inside the actuating motor enclosing body, with a tubular discharge element integrated inside the gripping handle, and ending with a connector. According to a preferred embodiment, the channels of said suction system provided within the motor-enclosing body comprise a chamber for a suction fan directly keyed onto the driving shaft. In this case, the machine tool has its exhauster incorporated and a collecting container for exhausted chips and dust may be connected to the connector provided on the gripping handle,either directly or indirectly though a pipe. It is however also possible to use an external exhauster to be connected to the connector on machine gripping handle. The adoption of the suction system with channels and ducts entirely accomplished and provided in the inside of the milling and/or trimming machine tool, as envisaged according to the invention, makes the machine of more prac tical use, by eliminating any outer components, and allows a cheaper and faster assemblage than solutions envisaging the adoption of separate parts such as pipes, suction ports, and so forth. Said guide system comprises preferably a plurality of elements, at least one of said elements being constituted by a rod bearing a graduated portion and a threaded portion, said graduated portion being sliding within a seat provided in said base plate, a locking means for said rod being provided, and said threaded portion complementarily coupling within a ring, it too being threaded, rotatably positioned within said upper body, elastic elements acting between said plate and said body being moreover provided. An exemplifying embodiment of the machine according to the invention shall be disclosed hereinunder with reference to the attached drawings, wherein: Fig. 1 is an elevation side view of the machine, Fig. 2 is an elevation front view, Figs. 3, 4 and 5 are sections respectively along the lines III-III, IV-IV and V-V of fig 1, Fig. 6 is a vertical section anoag the line VI-VI of fig. 2, Fig. 7 is a view from the bottom according to the arrow VII of fig. 1, Fig. 8 is a section along the line v VIII of fig. 1, Figs. 9 and 10 show a section of the supporting plate with two different types of toots during the machining of e.g. wood, and Fig. 11 is a section along the line XI-XI of fig. 6. As it can be observed from the drawings, the portable electrical machine tool comprises a body formed by an upper closure cap 1, by a central portion 5 and by a lower portion 9, these parts being all rigidly connected with each other so as to constitute a single body which supports and encloses a vertical-axis electrical motor 21, whose shaft 22 bears at its lower end a mandrel 23 suitable to contain a tool 18. This body is guided, by means of sleeves 20, along a guide tube 12 rammed in correspon dence of its lower end into a cup-shaped seat 24 provided in a supporting plate 7 inferiorly closed by a closure sheet 8, provided with a central aperture 25. The plate 7 is provided with a central aperture 26 for the passage of the tool 18 during it motion downwards, to move from a rest position to a lowered-down operative position. Inside said aperture 26 a plurality of ports 27 are provided, which, together with an annular port 28,pro vided between said central aperture 25 and the walls of the central aperture 26, allow the exhausting towards at least one chamber duct 29. On the end of said duct 29 a bellows element 6 is fastened, which concentrically surrounds the guide tube 12 wherein a spring or elastic element 17 is contained, acting between said cup-shaped seat 24 and a distancer rod 16, which normally holds the body of the machine tool in its lifted rest position by reacting in the upper cap 1. Advantageously, said distancer rod 16 may be varied in order to intervene on the load of the helical spring 17, allowing a more or less fast reverse stroke in case of machining operations of the plunging type. A second duct 30 is thus accomplished, which deliv ers the exhausted dust/air mixture into a chamber 31, defined by an upper baffle wall 14 and by a lower baffle wall 15 provided with an annular and central opening 32, said chamber 31 being positioned above a fan 13 solidly keyed onto the shaft 22. Said fan 13 directs air towards a discharge tubular element It ending into a connector or fitting 3, said tubular element 4 constituting moreover the lower portion of a gripping handle 33 which protrudes from the central portion 5 of the body of the machine. Within said gripping handle, essentially of a reverse-"U" shape, a feeding cable 34 for the motor 21 is housed. Advantageously, an adjustment device, as indicated with 10, of the operating depth of the tool 18 inside an underlying material 19, e.g., wood, may be provided. The adjustment device 10 is constituted by a shaped rod bearing a lower graduated portion 35, sliding within a suitable complementary seat 36, said complementary seat 36 being provided with a locking means 11, of the thumbscrew type with end locking screw acting on the same graduated portion. A threaded upper portion 37 of the rod is complementarily coupled with a ring 2, it too threaded, rotatably positioned inside a seat 38 of the cap 1, from which it is partly protruding. In the lower portion 9 of the body, in correspondence of said adjustment device, a seat 40 open outwards, where in the graduated portion 35 slides, is provided, and inside the cap 1 an inner seat 39 is provided, inside which the threaded portion 37 slides. It results thus very clear that, when a machining of the plunging type is to be carried out, by acting on the threaded ring 2 to cause the threaded portion 37 to slide inside its related seat 39 (see fig. 11), as a consequence the operating stroke of the tool machine, and more precisely of the same tool, is adjusted. During this operation, the locking means 11 must not act on the graduated portion 35. If on the contrary one wishes to carry out a trimming or milling operation with predetermined machining in tervention depth, it is enough to act on the locking means 11, which, through the locking screw extending from it, acts on the graduated portion 35 of the rod, locking it. Said device may consequently afford a double adjustment both of the plunging- and/or of the pass-machining depth by means of a threaded ring 2, and of the material remov al in position at fixed depth, by means of a locking means 11 for the guide elements of the downwards run from the rest position to the working position. The operating fashion e.g. in the plunging mode of the electrical machine tool is easily disclosed. The working depth is preset and predetermined as hereinabove disclosed by acting on the threaded ring 2 and presetting hence the possible run downwards of the body along the guide tube 12 and consequently of the tool 18, e.g., into wood 19. By acting on the gripping handle 33 the downwards motion of the tool 18 towards the wood 19 is determined, thus starting the milling operation (fig. 9). The chips produced and the powder material generated are exhausted both by the annular port 28 and by the small ports 27 provided in the supporting plate 7. They pass then into the first duct 29, into the sec ond duct 30 of the bellows element 6 and from there into the chamber 31, from which they flow outwards as sucked by the fan 13 from the annular opening 32 towards the dis charge tubular element 4, e.g., connected via the fitting 3 to a (not shown) container such as a bag or a pipe connected to a remote collection means (they too being not shown). It can be noted that dust and chips of wood, or of other possible materials being handled, such as plastic material, fiberglass, etc.,- to not spread around thus disturbing the operator or hiding the concerned working area, but are withdrawn as soon as they are generated. The ducts 29, 30 and the channels of the fan exhausting system 13, as being completely housed within the tool machine, make it particularly practical in use, and particularly advan tageous from the viewpoint of the overall dimensions. The fan 13 may also be not provided, if one plans to connect the fitting 3 and consequently the end tubular element to a external (not shown) exhausting means. A system of ducts and ports provided in the plate 7 and in its closure sheet 8 besided to the tubular element 4, intended for application under the gripping handle 33, allow a quick assemblage and an as much quick maintenance, without the provision or the connection of particular out er units or parts.

Claims: Claims 1.Portable electrical milling and/or trimming machine tool for the machining of a material with the production of chips and/or dust, comprising a body encasing a vertical-axis electrical motor for the actuation of the tool, provided with a gripping handle and slidingly mounted by means of a guide system relatively to a support plate provided with a central aperture for the passage of the tool, characterized in that said machine incorporates a suction system for said chips and said dust comprising in said sup porting plate at least a duct communicating on one side with suction openings coming in correspondence of said plate central aperture and on the other side with a duct concentrically formed around said guide system by a bellows sleeve surrounding this guide system, this latter duct being in its turn in communication, via channels provided inside the actuating motor enclosing body, with a tubular discharge element integrated inside the gripping handle, and ending with a connector. 2. Portable machine tool according to claim 1, char acterized in that said channels provided inside the motor enclosing body comprise a chamber for an exhausting fan directly keyed onto the driving shaft. 3. Portable machine tool according to claim 1, characterized in that said central aperture of said supporting plate is defined by a closure sheet provided with a central aperture, and defining moreover an exhaust annular port concentrically outer relatively to said suction openings. 4. Portable machine tool according to claim 1, characterized in that, said guide system is at least a hollow tube inside which an elastic element acting between said support plate and an upper cap of said body is positioned. 5. Portable machine tool according to claim 1, char acterized in that said discharge tubular element integrated inside the gripping handle is additionally a closure half-element for said gripping handle, having a re verse-#U11 shape. 6. Portable machine tool according to claims 1 and 2, characterized in that within said body, above said fan a suction chamber is provided, defined by an upper wall and by a lower wall, said chamber being connected on one side to said bellows duct, and on the other side to the seat of said fan via an annular opening. 7. Portable machine tool according to claim 1, characterized in that said guide system comprises a plurality of elements, at least one of said guide elements being constituted by a rod bearing a graduated portion and a threaded portion, said graduated portion being sliding in side a seat provided in said supporting plate, a locking means for said rod being provided, and said threaded portion complementarily coupling within a ring, it too threaded, rotatably positioned inside said upper body, elastic elements acting between said plate and said body being moreover provided. 8. Portable machine tool according to claim 4, characterized in that inside said at least one hollow tube a spacer element is additionally provided.

Inventors: VALENTINI, GUIDO
Applicants: VALENTINI, GUIDO
Application year: 1986
Main classification: B24B23
IPC codes: B23Q11, B28D7, B24B55, B28D1