GB2399314A

GB2399314A - Tool having rotatable adjustment means for power working member

Info

Publication number: GB2399314A
Application number: GB0305713A
Authority: GB
Inventors: Stephen Houghton
Original assignee: Black and Decker Inc
Current assignee: Black and Decker Inc
Priority date: 2003-03-13
Filing date: 2003-03-13
Publication date: 2004-09-15
Anticipated expiration: 2023-03-13
Also published as: GB0305713D0; GB2399314B

Abstract

A jigsaw 2 having a housing 4 and a jigsaw blade 8 mounted to a blade support 10 is disclosed. The blade support 10 is mounted to bearing 18 in the housing to enable the blade 8 to rotate about its axis 20 of reciprocating motion. An upper part of the housing 4 is provided with a circular track surrounded by a circular rubber grip 24, and a steering knob 26 is rotatable mounted to the circular track at a radially outer part thereof. The remaining part of the circular track not occupied by the steering knob 26 defines an aperture 28 through which a user of the jigsaw 2 can view the location at which the jigsaw blade 8 cuts through a workpiece.

Description

23993 1 4

POWER TOOL HAVING ROTATABLE ADJUSTMENT MEANS FOR WORKING

MEMBER

The present invention relates to a power tool having a rotatable adjustment means for a working member thereof, and relates particularly, but not exclusively, to a jigsaw for enabling a blade thereof to be rotated about its axis of reciprocating motion to enable curves to be cut.

It is known to provide jigsaws with a scroller function which allows the jigsaw blade to be rotated about its drive axis so that a user may cut curves without the need to move the body of the jigsaw. This feature is particularly useful in situations where space is limited, in which the body of the jigsaw may come into contact with obstructions and limit the range of cutting angles available to the blade.

Known jigsaws having a scroller function suffer from the drawback that the mechanism allowing rotation of the jigsaw blade about its drive axis and the method of holding and/or guiding said mechanism obscures viewing of the jigsaw blade by the user during use. As a result, it is difficult for the user to view that part of the workplace that it contacted by the blade during cutting thereof, which may in turn have a detrimental effect on the accuracy of cutting achieved by the saw.

Preferred embodiments of the present invention seek to overcome the above

disadvantages of the prior art.

According to the present invention, there is provided a power tool comprising: a housing; a motor provided in the housing; an output shaft adapted to be actuated by said motor for causing reciprocating motion of a working member along a reciprocation axis; and adjustment means for pivoting said working member about said reciprocation axis, wherein said adjustment means and said housing are adapted to enable viewing of a location at which said working member cuts a wo,-kpiece by a user from a side of the housing remote from the working member whilst holding and operating said tool.

P-UK-CS] 47 By allowing a user to view the location at which the working member cuts a workpiece, this provides the advantage of improving the accuracy of cutting operations carried out using the tool.

Said adjustment means may comprise at least one actuating member movably mounted to said housing, such that movement of at icast one said actuating member relative to said housing in use causes pivotable movement of said working member about said reciprocation axis.

At least one said actuating member may be adapted to be pivoted about said reciprocation axis.

By making an actuating member pivotable about the reciprocation axis of the working member this provides the advantage of simplifying construction of the tool, by enabling the output shaft to be directly connected to the actuating member such that rotation of the actuating member about the pivot axis directly causes rotation of the working member about the reciprocation axis.

At least one said actuating member may be mounted to a curved track on said housing, and said curved track may at least partially define an aperture permitting viewing of said working member in use.

At least part of said curved track may be substantially circular.

Said actuating member may be mounted at an outer periphery thereof to said curved track.

This provides the advantage of enabling the region adjacent the pivot axis to be kept clear of components which may otherwise obscure viewing of the working member during use.

The tool may further comprise at least one gripping portion adjacent at least one said actuating member.

P-UK-CS] 147 The tool may further comprise locking means for locking the working member in at least one predetermined orientation about said reciprocation axis relative to said I housing.

5The tool may further comprise support means for abutting the working member at a location separate from said output member.

This provides the advantage of improving operation of the working member by supporting the working member during use thereof, and also prolongs the life of the 10working member.

Said support means may comprise at least one roller.

The tool may be a jigsaw.

A preferred embodiment of the invention will now be described, by way of example only and not in any limitative sense, with reference to the accompanying drawings, in which: Figure 1 is a side elevation view of a jigsaw embodying the present invention; Figure 2 is a perspective view from one side and above of the jigsaw of Figure 1; Figure 3 is a perspective view from the front and above of the jigsaw of Figure 1; Figure 4 is a view from above of the front portion of the jigsaw of Figure 1; and Figure 5 is a perspective view from the front and one side of the front portion of the jigsaw of Figure 1.

Referring to Figures 1 to 3, a jigsaw 2 has a housing 4 accommodating a motor (not shown) to which electrical power is supplied by a power cord 6. Actuation of the motor by means of a suitable trigger switch (not shown) provided on the housing 4 P-UK CS] ,47 causes reciprocating motion of a saw blade 8 via a suitable drive mechanism such as a scotch yoke mechanism (not shown) which, as will be appreciated by persons skilled in the art, causes reciprocating motion of a support 10 for the jigsaw blade 8 in response to rotary motion of an output shaft of the motor. The housing 4 of the jigsaw 2 is mounted to a jigsaw support shoe 12 having an aperture 14 (Figures 2 and 3) through which the saw blade 8 extends, and the housing 4 is pivotable relative to the support shoe 12 to enable bevel cutting by the jigsaw. The shoe 12 can be locked in a number of orientations relative to the housing 4 by means of a suitable locking mechanism (not shown).

A dust blower 16 is mounted to the support shoe 12 and has an outlet arranged adjacent the blade 8 and to one side thereof for blowing dust away from the location at which the blade 8 cuts a workplace (not shown), in a direction transverse to the line of action A of the jigsaw as shown in Figure 1. This avoids the dust blower 16 obscuring the user's view of the blade 8 while also allowing the blower outlet to be arranged as close as possible to the blade 8 to make the blower as effective as possible. The dust blower 16 also has an inlet connected via a duct in the housing 4 to a fan (not shown) used to cool the jigsaw motor.

The blade support 10 is rotatably mounted to a bearing 18 in the housing to that the blade 8 can rotate about its axis 20 of reciprocating motion. An upper part of the housing 4 is provided with a circular track 22 (Figures 2 and 3) which is surrounded by a circular rubber grip 24. A steering knob 26 is rotatably mounted to the circular track 22 at a radially outer part thereof, the remaining part of the circular track 22 not occupied by the steering knob 26 defining an aperture 23 through which a user of the jigsaw can view the jigsaw blade 8 at a location at which it cuts a workpiece. The steering knob 26 is rotatable about the axis 20 of reciprocation of the blade 8, such that rotation of the steering knob 26 about axis 20 also causes rotation of the jigsaw blade 8 about the axis 20. T he steering knob 26, and therefore the jigsaw blade 8, can be locked in a series of scrolling positions by means of a scroller lock switch 30 provided on the housing 4.

Referring now to Figure 5, a blade support roller 32 carried by a support 34 connected to steering knob 26 and integral with blade support 10 abuts a rear edge (i.e. the non-cutting edge) of the jigsaw blade 8 to provide additional support to the P-UK-CS 1 it7 blade 8 during normal cutting operation, and during pendulum motion actuated by orbital action switch 36 (Figure 1) in which the blade 8 oscillates about an axis generally perpendicular to axis 20 to provide an improved cutting action. This is achieved in the pendulum mode by means of the blade support mechanism including the drive shaft and roller support 34 pivoting as a single unit relative to the housing when the blade 4 is oriented in the "in-line" direction as shown in Figure 5. The blade support roller 32 also improves the accuracy of cutting of the jigsaw and increases the useful lifetime of the jigsaw blade 8. The blade support roller 32 rotates about axis 20 with the blade 8 so as to remain in contact with the blade 8, regardless of the scroller position in which the jigsaw blade 8 is arranged.

The operation of the jigsaw 2 shown in the Figures will now be described.

In order to cut a workpiece, the housing 4 of the jigsaw 2 is fixed in the desired orientation relative to the support shoe 12 and the blade 8 then fixed in the desired orientation about axis 20 relative to the housing 4 and fixed in position relative to the housing 4 by means of scroller lock switch 30. The trigger (not shown) provided on the housing 4 is then depressed to supply electrical power to the motor (not shown), actuation of the motor also actuating the motor fan, which supplies a stream of air via the outlet of dust blower 16 to the side of the jigsaw blade 8. An inlet (not shown) to a dust extraction tube, connected to a suitable suction source such as a vacuum cleaner, can also be provided on the opposite side of the blade 8 to the dust blower 16 to extract dust blown away from the location at which the blade 8 cuts the workpiece. During cutting of the workpiece, the user can view the blade 8 via aperture 28 at all scrolling orientations of the blade 8 relative to the housing.

It will be appreciated by persons slcilied in the art that the above embodiment has been described by way of example only, and not in any limitative sense, and that various alterations and modifications are possible without departure from the scope of the invention as defined by the appended claims.

P-Ut(-CS] 47

Claims

1. A power tool comprising: a housing; a motor provided in the housing; an output shaft adapted to be actuated by said motor for causing reciprocating motion of a working member along a reciprocation axis; and adjustment means for pivoting said working member about said reciprocation axis, wherein said adjustment means and said housing are adapted to enable viewing of a location at which said working member cuts a workplace by a user from a side of the housing remote from the working member whilst holding and operating said tool.

2. A tool according to claim 1, wherein said adjustment means comprises at least one actuating member movably mounted to said housing, such that movement of at least one said actuating member relative to said housing in use causes pivotable movement of said working member about said reciprocation axis.

3. A tool according to claim 2, wherein at least one said actuating member is adapted to be pivoted about said reciprocation axis.

4. A tool according to claim 2 or 3, wherein at least one said actuating member is mounted to a curved track on said housing, and said curved track at least partially defines an aperture permitting viewing of said working member in use.

5. A tool according to claim 4, wherein at least part of said curved track is substantially circular.

6. A tool according to claim 4 or 5, wherein said actuating member is mounted at an outer periphery thereof to said curved track.

7. A tool according to any one of claims 2 to 6, further comprising at least one gripping portion adjacent at least one said actuating member.

P-UK-CS1 147

P-Ul<-CS,,47

8. A tool according to any one of the preceding claims, further comprising locking means for locking the working member in at least one predetermined orientation about said reciprocation axis relative to said housing.

9. A tool according to any one of the preceding claims, further comprising support means for abutting the working member at a location separate from said output member.

10. A tool according to claim 9, wherein said support means comprises at least one 1 0 roller.

11. A tool according to any one of the preceding claims, wherein the tool is a jigsaw.

12. A power tool substantially as hereinbefore described with reference to the accompanying drawings.

P-UK-CS] 147 ! Amendments to the claims have been filed as follows l. A power tool comprising: a housing; a motor provided in the housing; an output shaft adapted to be actuated by said motor for causing reciprocating motion of a working member along a reciprocation axis; and adjustment means for pivoting said working member about said reciprocation axis, wherein said housing and/or adjustment means comprises at least one aperture to enable viewing, through at least part of said housing, of a location at which said working member cuts a workplace by a user from a side of the housing remote from the working member whilst holding and operating said tool.

4. A tool according to claim 2 or 3, wherein at least one said actuating member is mounted to a curved track on said housing, and said curved track at least partially defines at least one said aperture permitting viewing of said working member in use.