The present invention relates to an assembly for removing chips and cuttings from a cutting working area of a cutting tool on a workpiece. The assembly of the present invention is adapted to be attached to either an axially movable, non-rotating component of a drilling/milling machine and be resiliently biased towards a workpiece in which a hole or a recess is to be formed, or to be attached to a separate fixed support or stand located close to the workpiece and be resiliently biased towards the machine. In particular, but not exclusively, the assembly is adapted to be used together with orbital drilling machines.
When forming holes or recesses in a workpiece by means of a drilling or milling machine chips and cuttings generated by a cutting tool and remaining in the vicinity of the hole during the forming thereof can adversely effect the surface quality of the hole being formed.
An object of the present invention is to provide a chips-removing assembly, which can efficiently collect and remove chips from a cutting working area while at the same time obtaining a full protection of the cutting tool in the zone between an advancing nose portion of the machine and the workpiece during a working operation.
For this purpose the assembly of the present invention comprises, in its simplest form, a support structure for supporting a first end of an axially expandable and collapsible tubular member; a cross-piece for supporting a second end of the tubular member; at least one biasing spring configured and arranged for resiliently biasing the support structure and the cross-piece away from one another, a housing with a chips-receiving chamber located adjacent one of said ends of the tubular member for engagement with the working area of the workpiece, an outlet from the chamber of the housing being configured to be connected to a vacuum source for removing chips from the chamber; and a hub portion located at the other of said ends of the tubular member for engagement with a cutting machine. During the working operating the tubular member surrounds the shaft of the cutting tool and defines a space which is substantially closed against a nose portion (e.g. a rotating spindle) of the working machine and which communicates with the chips-receiving chamber so as to improve the evacuation of chips therein and to create a safe protection for the operator in case of a breakdown of the cutting tool.
Further features and suitable embodiments of the assembly of the present invention are defined in the claims and will be described more in detail in the following description under reference to the accompanying drawings.
In use the housing 4 is set into engagement with the surface of the workpiece where a hole or recess is to be formed therein. The telescopic tubular member 6 is allowed to axially expand over the cutting tool and its shaft (not shown) so as to bring the pressure plate P to resiliently engage the advancing spindle of the cutting machine. During the advancement of the cutting tool into the workpiece the tubular member 6 will axially collapse successively against the action of the spring force of the resilient member 6. The tubular member 6 forms both a confined space communicating with the chips-receiving chamber 5 so as to improve the evacuation of chips therein, and a strong protection of the cutting tool in a zone between an advancing nose portion of the machine and the workpiece during a working operation.
The assembly 11 comprises a U-shaped support structure 16 having two opposed side legs 18 with a rear fastening section 20 for fixating the support structure 16 to the axially movable housing 12 of the machine 14. The legs 18 are interconnected by a central hub portion 22 which has a cylindrical recess 24 for receiving a front end of an orbiting spindle carrying a rotary cutting tool (not shown) with a small axial play between the bottom of the recess and the end of the spindle. To the outer side of each leg 18 is mounted a respective guide block 26 for linear guidance of two guide rods 28. A cylinder 30 of a pneumatic spring generating a substantially constant spring force is attached to the rear end of each leg 18 and to the guide block 26 and has a piston rod 32 extending through the block 26. The guide rods 28 and the piston rod 32 are fixated to a respective end of a yoke-shaped pressure foot 34, which interconnects the two pairs of guide rods 28 and the piston rods 32. The pressure foot 34 carries a central circular housing 36 defining a chamber 38 for receiving cuttings from the hole or recess being formed in a workpiece against which the pressure foot 34 is biased by the pneumatic springs 30, 32. The chamber 38 communicates with a channel 40, which extends through a branch 42 of the pressure foot 34 and is connected to a vacuum source (not shown) via a tubular outlet socket 44. The one end of an axially expandable and collapsible tubular member 46 is attached to the central housing 36, while the other end is attached to the central hub portion 22 of the support structure 16. The tubular member 46 is configured to accommodate the cutting tool and to define a substantially closed space around it, which could be reduced in volume when the cutting tool advances into the workpiece. The tubular member 46 preferably consists of a telescopic spring made of a helically wound strip 48 of a spring material, such as spring steel. Such a tubular member 46 may easily be collapsed to an axial dimension substantially equal to the width of the strip 48. Alternatively, the tubular member 46 may be formed as a resilient bellows. In its most expanded position the axial length of the tubular member 46 is such that the tip of the cutting tool mounted to the orbiting spindle will not protrude from the surface of the central housing 36 which engages the workpiece.
When starting a hole-forming procedure the pressure foot 34 is held at a maximal extended position relative to the drilling machine by means of the pneumatic springs 30, 32. The housing 12 of the orbital drilling machine 14 is fed axially towards the workpiece by an axial feed motor 50 (
In contrast to the second embodiment, the assembly 52 of the third embodiment is configured to be mounted to a support 54, which is fixed relative to the workpiece 56 during the working of a hole therein. The assembly 52 comprises a central upright member 58 attached to the support 54 via an axially adjustable piston rod 60 (
The cross-piece 82 also holds one end 88 of an axially expandable and collapsible tubular member 90, the other end 92 of which is attached to the upright 58 concentrically to housing 62. Like in the first and second embodiments, the tubular member 90 is configured to accommodate the cutting tool and to define a substantially closed space around it, which could be reduced in volume when the cutting tool advances into the workpiece. Thus, the tubular member 90 preferably consists of a telescopic spring made of a helically wound strip 94 of a spring material, such as spring steel. Such a tubular member 90 may easily be collapsed to an axial dimension substantially equal to the width of the strip 94.
The pneumatic spring units 72, 74 are adapted to generate a substantially constant spring force that bias the tubular member 90 towards the end surface 86 of the tool spindle through the pressure plate 84. As shown in
It should be noted that the pneumatic springs 30 and spring units 72, 74 referred to above could alternatively be formed as hydraulic or electric units for controlling the expansion and retraction of the tubular member 46, 90.
Number | Date | Country | Kind |
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60319579 | Sep 2002 | US | national |
604143408 | Sep 2002 | US | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/SE03/01500 | 9/26/2003 | WO | 9/23/2005 |