Abstract: A brush assembly preferably for a universal motor comprises a tubular brush holder 13, a carbon brush 33, an arm 31 for biasing the brush and a spring 85 for biasing the arm. The brush is slidably mounted in the cavity 21 of the holder. A stop 61 is formed between the brush and the holder and has a disengaged position to permit travel of the brush partially through the inner end 25 of the holder and an engaged position to limit travel of the brush through the inner end 25 of the holder. The electrically conductive arm 31 is pivotally mounted on the support and extends through a slot 29 of the holder. A distal end 60 of the brush engages the outer end 53 of the brush and biases the brush 33 toward the inner end 25 of the cavity. The spring 85 is connected between the support 15 and the arm 31 for biasing the arm 31 into engagement with the brush 33. The arm is spaced outwardly of the end of the slot to apply a bias to the brush when the stop is in an engaged position.
Abstract: A roll-forged drill bit 1 comprising a shank 3 for insertion in a chuck of a drill, the shank 3 including an helically twisted web 7 defining a cutting tip 9, the cutting tip 9 including a central chisel edge 11 and a cutting edge 15 defining the maximum diameter of the cutting tip 9, wherein the cutting tip 9 is formed after the shank 3 has been roll-forged and includes a pair of faces 13 defining the chisel edge 11 and a pair of upturned flats 17 defining the cutting edge 15. A roll-forged drill bit 1 according to the present invention provides a significant improvement in cutting speed over known prior art roll-forged drill bits.
Type:
Grant
Filed:
July 25, 1996
Date of Patent:
September 5, 2000
Assignee:
Black & Decker Inc.
Inventors:
Michael Mulroy, Rudolf Jungwirth, Johann Riedl
Abstract: A rotary hammer with a tool holder and a hammer mechanism for the transmission of impact energy onto the drilling and/or chiselling bit in the tool holder has a switching device which with a single actuator makes it possible to switch between pure drilling operation, rotary hammering operation and pure hammering operation. The switching device acts on a coupling with which the hammer mechanism is couplable with a rotatingly driven intermediate shaft, and has a slide part for shifting a toothed wheel between a first position for the rotary driving of the tool holder and a second position in which no rotary driving of the tool holder takes place. The coupling for the hammer mechanism can be separated by a cam part coupled in untwistable manner with the actuator.
Abstract: An adjustable interconnected lockset adapted to be secured to a door which includes a mounting plate assembly having a vertically extending mounting plate having an operator bracket proximate the bottom thereof with the operator bracket having screw receiving holes. The lockset also has an exterior operator assembly including internally threaded posts, first screw holes extending through the mounting plate and screws which extend through the mounting plate and threadedly engaging with the threaded posts to clamp the door between the exterior operator assembly and the mounting plate assembly. The mounting plate has a central opening extending vertically upwardly from a location proximate the operator bracket and defining mounting plate side panels on either side thereof and the mounting plate assembly further has a dead bolt bracket which includes a central door engaging portion, a pair of opposed side portions adapted to engage the mounting plate side panels, and screw receiving holes.
Abstract: Significantly improved resistance to breaking while drilling in metal can be realized in twist drill bits having a web thickness taper which is about twice the web thickness taper specified in Standards and in common use in the industry. This creates much shallower flutes and flies in the face of conventional wisdom in the art which holds that the web taper rate should be low to maximize the amount of flute volume available to convey chips and sawdust out of the hole. A flute length of about 1/2" less than the flute lengths specified by the Standards makes it possible to have such a large taper rate but still control variations in tolerances for the flute length. It also provides a marking zone for placing size indicia on the drill bit shank outside the portion which is, ripped by the chuck jaws of a power drill.
Abstract: An abrasive sheet 1 for a sanding or polishing machine, comprising a body portion 3 and a tip portion 5 providing a working point 11, the tip portion 5 being defined by a weakened region 7 between the body portion 3 and the tip portion 5, wherein the tip portion 5 can be separated from the body portion 3, turned through an angle (FIG. 2) and re-positioned adjacent the body portion 3 to change the working point 11. As a result, an iron-shaped abrasive sheet, for example, can be provided with a plurality of working points 11. The sheet can, therefore, be used for longer periods before it is worn out.
Type:
Grant
Filed:
March 6, 1997
Date of Patent:
April 4, 2000
Assignee:
Black & Decker Inc.
Inventors:
Michael Martin, Colin Pugh, Eric Cockburn
Abstract: A masonry drill bit having an active diameter of D, comprising a shaft and a tip 1 for engaging a workpiece, wherein the tip 1 is formed with a plurality of stepped portions shaped to cut a workpiece as the drill bit rotates. By virtue of the drill bit tip 5 configuration as described and claimed herein, a masonry drill bit 1 having improved performance is provided.
Type:
Grant
Filed:
September 17, 1997
Date of Patent:
February 8, 2000
Assignees:
Black & Decker Inc., Plansee Tizit
Inventors:
Rudi Birk, Werner Ferstl, Ronald Huber, Walter Lempach