Biscuit joiner

Information

  • Patent Grant
  • 6260591
  • Patent Number
    6,260,591
  • Date Filed
    Wednesday, August 11, 1999
    25 years ago
  • Date Issued
    Tuesday, July 17, 2001
    23 years ago
Abstract
A biscuit joiner (10) having a housing (16) which includes a forward portion (26), a handle portion (28) and a rear portion (30). A battery pack (56) is removably secured to the rear portion. The forward portion houses an electric motor (32) and is attached to a shoe assembly (12) and a fence assembly (14). The handle portion includes a stick handle portion (40) and a loop portion (42). Each of the stick handle and loop portions are laterally offset from the forward portion, and therefore from the rotational axis of the motor and the coaxial center of the housing. The stick handle portion is graspable by a user and the lateral offset enables the fingers of the user to be placed in position to exert a force substantially along the longitudinal axis (36) of the motor while engaging an ON/OFF trigger (46) of the joiner. In this manner a more direct application of force can be made by the user to the housing when urging the housing linearly while making plunge cuts with the joiner. The handle construction also provides the joiner with a well balanced, positive “feel” and enables a wider variety of hand orientations to be used when operating the joiner. The joiner of the present invention is even more comfortable to operate than previously developed stick handle type joiners, even with the additional weight of the removable battery pack, and can therefore reduce the fatigue of the user's hands and arms when the joiner is operated over prolonged periods of time.
Description




TECHNICAL FIELD




This invention relates to plate or biscuit joiners, and more particularly to a cordless biscuit joiner having an ergonomically formed handle portion to enable a user to more comfortably handle the tool more closely to the center of gravity of the tool, and to exert a linear force substantially along the longitudinal axis of the motor of the tool to thus further improve the operator's control over the tool and to further reduce operator fatigue when using the tool.




BACKGROUND OF THE INVENTION




Biscuit joiners are used in a variety of wood-working applications to cut slot-like recesses into the surfaces of wood members that are to be joined in facing relationship to one another. Typically, glue is applied to one or both of the recesses and a wood disc-like member termed a “biscuit” is urged into one of the recesses such that it projects partially therefrom. The other wood member is placed adjacent the protruding edge of the biscuit and the protruding edge is then urged into the recess of the facing wood member as the two wood members are forced against each other.




Traditional biscuit joiners typically incorporate some form of shoe assembly which houses the cutting blade. A fence assembly allows the wood member to be positioned thereagainst at a desired angle relative to the shoe assembly. A stick-type handle/housing is secured to the shoe assembly and encloses the electric motor of the tool. The rear portion of the handle/housing forms a generally cylindrical stick-type handle which the user grasps when using the joiner. The user exerts a force toward the wood member being cut which causes the cutting blade to be urged outwardly of the shoe assembly to thereby cut the slot-like opening in the wood member. One such type of joiner is presently offered by the assignee of the present application in an AC powered version, which has been very well received in the industry.




When adding a battery pack to a stick-handle type joiner, it is even more important to consider the ergonomics of the tool and how the additional weight of the battery pack influences the overall feel and comfort of use of the tool. Preferably the battery pack should not upset the overall balance of the tool or require additional effort to be expended by the user when using the tool just to compensate for the additional weight of the battery.




With traditional joiners having a stick-type handle, the precise orientation of the stick handle portion of the tool has been found to significantly influence the ease and comfort with which the joiner can be operated. In this regard, it has been found that orientating the stick handle relative to the longitudinal axis of the motor is an important factor in helping to achieve an even more balanced, positive “feel” during use of the joiner. Specifically, it has been found that if the stick handle portion of the joiner housing is offset laterally a small degree from the longitudinal axis of the motor, that a significant enhancement in the comfort and “feel” of the tool can be achieved. This is because the forward force applied by the user with the hand that is grasping the stick handle portion is applied even more directly along the longitudinal axis of rotation of the motor, and thus the main body portion of the tool.




Offsetting the stick handle portion slightly from the rest of the housing also enables the user to grasp the stick handle portion more forwardly thereon (i.e., to “choke up” on the stick handle portion) with his/her hand, thus enabling the user's hand to be placed closer to the overall center of gravity of the tool. These erogonomic improvements can help to significantly improve the comfort, balance and overall “feel” of the joiner, as well as to reduce the fatigue experienced by an individual when using the joiner over a prolonged period of time.




Accordingly, it is a principal object of the present invention to provide a biscuit joiner having a handle assembly which serves to place the hand of the user that is used to engage the ON/OFF trigger of the tool in an orientation which is even more comfortable and ergonomically efficient for the user. More specifically, it is an object to form the stick handle portion of the tool such that the user is able to exert a force, when using the tool, that is directed substantially along the longitudinal axis of the main body of the joiner. In this manner the force transmitted by the user's hand which is gripping the stick handle portion can be transmitted even more efficiently and comfortably when making plunge cuts with the joiner.




It is a further object of the present invention to provide a stick handle type biscuit joiner having a handle that is laterally offset slightly from the main body portion of the joiner to increase the ease with which a user can grip forwardly on the stick handle. This would enable the user to grasp the joiner closer to its center of gravity, and thus further contribute to a positive, well balanced “feel” when using the tool.




It is a further object of the present invention to provide a biscuit joiner having a handle assembly which helps to support the joiner on a planar work surface when the tool is not in use.




It is yet another object of the present invention to provide a stick handle type biscuit joiner which is powered by a removable, re-chargeable battery pack.




SUMMARY OF THE INVENTION




The present invention is directed to a biscuit joiner having an ergonomically designed handle assembly. The handle assembly comprises a stick handle portion and a loop portion. The stick handle portion is laterally offset from a motor housing portion of the joiner which encases an electric motor. The lateral offset of the stick handle portion even further improves the transmission of force by the hand that is grasping the stick handle portion during use of the joiner. The lateral offset of the stick handle portion also enables the user to grip more forwardly on the stick handle portion such that the hand that is grasping the stick handle portion is able to placed closer to the overall center of gravity of the joiner.




In one preferred embodiment the joiner comprises a cordless joiner having a removable, rechargeable battery pack. The joiner also includes a loop handle portion formed underneath the stick handle portion. The loop handle portion and the battery pack can both help to support the tool on a flat work surface when the tool is not in use. The loop handle portion can also enable the user to grasp and support the joiner with a wider variety of hand positions during use of the tool.




The various preferred embodiments provide a biscuit joiner which is more ergonomically efficient and even more comfortable to operate than previously designed joiners, even when a rechargeable battery pack is attached to the rear area of the joiner. The stick handle and loop handle portions further enable a wider variety of hand positions to be accommodated comfortably when using the joiner while providing the tool with a well balanced “feel”. These features help to reduce operator fatigue when using the joiner over a prolonged period of time.











BRIEF DESCRIPTION OF THE DRAWINGS




The various advantages of the present invention will become apparent to one skilled in the art by reading the following specification and subjoined claims and by referencing the following drawings in which:





FIG. 1

is a fragmentary side view of a preferred embodiment of a biscuit joiner of the present invention with a portion of a two-piece clamshell handle portion thereof broken away to illustrate the various components disposed therewithin;





FIG. 2

is a side elevational view of the biscuit joiner of

FIG. 1

;





FIG. 3

is a top plan view of the joiner of

FIG. 2

;





FIG. 4

is a side elevational view of the biscuit joiner of

FIG. 2

illustrating how the lateral offset of the handle portion enables the fingers of a user to apply a linear force substantially along the longitudinal axis of rotation of the electric motor within the housing;





FIG. 5

is a side elevational view of the biscuit joiner of

FIG. 2

illustrating a hand of a user gripping at a more forward position on the stick handle portion;





FIG. 6

is a side elevational view of the biscuit joiner of

FIG. 2

illustrating a hand of a user gripping at an extreme forward position on the stick handle portion; and





FIG. 7

is a side elevational view of the biscuit joiner of

FIG. 2

illustrating the stick handle portion being grasped with a reverse grip to facilitate holding the joiner in a vertical orientation.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring to

FIGS. 1-3

, a biscuit joiner


10


is shown in accordance with a preferred embodiment of the present invention. Referring specifically to

FIG. 1

, the biscuit joiner generally comprises a shoe assembly


12


and a fence assembly


14


which are each attached to a housing


16


. The shoe assembly


12


has a recess


18


within which is disposed a cutting blade


20


. An opening


22


at a front portion


24


of the shoe assembly


12


enables the cutting blade


20


to be urged outwardly of the shoe assembly


12


during use of the joiner


10


.




The housing


16


includes a forward portion


26


, a handle portion


28


and a rear portion


30


. The forward portion


26


houses an electric motor


32


having an output shaft coupled to a gear reduction assembly


34


. The gear reduction assembly


34


has its output coupled to the cutting blade


20


. The longitudinal axis of rotation of the output shaft of the electric motor


32


, which coincides with the approximate coaxial center of the forward portion


26


, is indicated by arrow


36


. A forward handle


38


is secured to the forward portion


26


of the housing


16


. Further details of the construction of fence assembly


14


and the shoe assembly


12


can be found in U.S. Pat. No. 4,913,204, assigned to the assignee of the present application, and the disclosure of which is hereby incorporated by reference.




The forward portion


26


of the housing


16


is formed as a generally circular, single-piece section. The handle portion


28


extends from the forward portion


26


and is formed in a two-piece, clamshell-type configuration. The two housing halves comprising the handle portion


28


are held together by threaded screws


28


b that engage in four bosses


28




a


(only two of which are visible in FIG.


1


). The housing


16


is preferably manufactured from suitable high strength plastics through conventional injection molding techniques.




The handle portion


28


includes a main or stick handle portion


40


which is slightly oblong when assembled and viewed in cross-section. A foam-like material


40




a


which serves as padding for the user's hand can also be secured to an upper portion of the stick handle portion


40


by a suitable adhesive, as best seen in

FIGS. 2 and 3

. The stick handle portion


40


also includes an arcuate portion


40




b


providing a comfortable position for the user's thumb. As will be explained more fully in connection with

FIG. 5

, the arcuate portion


40




b


enables a user to grip the stick handle portion


40


more forwardly thereon so that the user's hand is closer to the overall center of gravity of the joiner


10


.




A loop portion


42


also extends from the forward portion


26


of the housing


16


to the rear portion


30


. Each of the stick handle portion


40


and loop portion


42


are formed so as to be offset laterally from the central longitudinal axis of the forward portion


26


, which coincides with the longitudinal axis of the forward portion


26


of the housing


16


and also with the longitudinal axis of rotation of the motor


32


, indicated by arrow


36


. This lateral offset enables a force to be transmitted by the user's hand even more directly along the longitudinal axis of the motor


32


and the forward portion


26


of the housing


16


, and therefore enhances the ergonomic efficiency and comfort to the user when using the joiner


10


.




The stick handle portion


40


of the handle portion


28


further includes an electrical ON/OFF switch


44


having a trigger portion


46


used for electrically closing the switch. The trigger portion


46


is disposed for sliding movement through an opening


48


in the stick handle portion


40


. The switch


44


is a normally open, spring biased switch which is electrically closed when the user actuates (i.e., squeezes) the trigger portion


46


.




The switch


44


is electrically coupled between the electric motor


32


and a terminal block


50


via suitable electrical conductors (not shown). The terminal block


50


is supported within a pair of channels


52


protruding from an interior surface


54


of the stick handle portion


40


. The terminal block


50


is used to electrically couple DC power from the electrical contacts of a removable battery pack


56


to the motor


32


when the battery pack


56


is attached to the housing


16


. The battery pack


56


is held removably to the housing


16


by a pair of identical, resilient latch arms


58


on opposite sides of the rear portion


30


of the housing


16


(with only one latch arm


58


being visible in

FIGS. 1

,


2


and


4


). The latch arms


58


extend through openings


60


formed in a casing


62


of the battery pack


56


and engage with the casing


62


to hold it securely to the rear portion


30


of the housing


16


.




The battery pack


56


is of the rechargeable type and therefore comprises one or more lead acid battery cells or nickel cadmium cells. It will be appreciated, however, that the joiner


10


could just as easily be modified to be powered from an AC power source. Also, it is anticipated that an AC/DC converter could also be used to provide power to the joiner


10


in place of the battery pack


56


. An AC/DC converter would be helpful in the event the battery pack


56


becomes discharged to the point where a task cannot be completed without first recharging the battery pack


56


. In this event, the AC/DC converter could be attached to the joiner


10


in place of the battery pack


56


and then a power cord of the converter plugged into an available AC power outlet. This would provide power to enable the joiner


10


to be used to complete the woodworking task at hand. It is further anticipated that such an AC/DC converter could be used with the joiner


10


with little or no modification to the joiner


10


. The only exception would be the need for the joiner


10


to be “double insulated”, as known in the art, to meet existing safety standards for AC powered tools.




The rear portion


30


of the housing


16


is also enlarged so as to be able to better mate with the battery pack


56


. By “enlarged” it is meant that the perimeter of the rear portion


30


extends laterally beyond the outer surface of the front portion


26


of the housing


16


. This feature also enables the rear portion


30


along with battery


56


to help support the joiner


10


when the joiner is rested on a planar work surface when not in use.




Referring now to

FIG. 4

, the operation of the joiner


10


will be described. It is a principal advantage of the joiner


10


that the stick handle


40


of the forward portion


26


is laterally offset from the longitudinal axis


36


about which the armature of the motor


32


rotates. This allows one grip to be used where the forefinger


64


of a user's and


66


, as well as the remaining fingers being used to grasp the stick handle portion


40


, are able to exert a force even more directly along the longitudinal axis


36


of the forward portion


26


of the housing


16


. This direct application of force along the longitudinal axis


36


provides the user with an even more positive and balanced “feel” when using the joiner


10


. It also substantially eliminates the small moment arm that could be created if the user is exerting a force which is directed along a line laterally offset from the motor rotational axis while making a plunge cut with the joiner


10


.




The laterally offset configuration of the stick handle portion


40


significantly adds to the comfort and ease in using the joiner


10


. This feature also serves to help reduce hand and arm fatigue when the joiner


10


is used repeatedly over a short period of time.




Referring to

FIG. 5

, another grip orientation is illustrated. Here the joiner


10


is illustrated with the user grasping the stick handle portion


40


at a more forward portion thereof. In this position, the hand


66


of the user that is grasping the stick handle portion


40


is very close to the center of gravity of the joiner


10


. This provides the user with an excellent sense of control and a balanced “feel” for the joiner


10


when handling and making plunge cuts with the joiner


10


.





FIG. 6

illustrates the stick handle portion


40


being grasped at a forwardmost portion thereof. With this grip the last two fingers of the user's hand


66


can be used to engage and hold the trigger portion


46


.





FIG. 7

illustrates the joiner


10


being held by the user's hand


66


with a reverse grip on the stick handle portion


40


. With this grip, the trigger portion


46


can be engaged by the second and third fingers


66




a


and


66




b


, respectively, while the joiner


10


is held in a vertical orientation.




The handle portion


28


thus enables a variety of hand positions to be used, which makes the joiner


10


even more comfortable to operate than existing stick handle type joiners when the joiner


10


is used to make plunge cuts in workpieces that are positioned in a variety of angular positions. The joiner


10


can thus be held easily and comfortably in a variety of positions while providing a well balanced and positive feel. Importantly, the offset orientation of the stick handle portion


40


permits the user to apply force directly along the housing


16


of the joiner


10


, thus providing a positive, balanced feel to the joiner


10


.




Those skilled in the art can now appreciate from the foregoing description that the broad teachings of the present invention can be implemented in a variety of forms. Therefore, while this invention has been described in connection with particular examples thereof, the true scope of the invention should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, specification and following claims.



Claims
  • 1. A joiner comprising:a housing having a forward portion and an elongated handle portion, said elongated handle portion including a trigger switch; an electric motor disposed within said forward portion of said housing, a longitudinal axis of said motor being aligned longitudinally with said trigger switch; a cutting blade operably associated with said motor so as to by driven by said motor; a shoe assembly for housing said cutting blade; and said elongated handle portion being graspable by a user and offset laterally from a longitudinal axis of said forward portion of said housing, to thereby place the fingers of a hand of the user approximately behind and generally longitudinally in-line with the forward portion of the housing and along said longitudinal axis of said motor when operating said joiner, thereby more effectively transmit a force exerted by said hand grasping said elongated handle to said cutting blade.
  • 2. The joiner of claim 1, wherein said elongated handle portion comprises a stick handle portion, and wherein said lateral offset of said stick handle portion is sufficient to place said fingers along a longitudinal axis extending through a coaxial center of said forward portion of said housing and through an axis of rotation of said motor.
  • 3. The joiner of claim 1, wherein said elongated handle portion comprises a stick handle portion and a loop portion both extending from said forward portion of said housing.
  • 4. The joiner of claim 3, wherein said stick handle portion includes a trigger switch operably associated with said electric motor and disposed so as to be engageable with a finger of the user's hand when operating said joiner.
  • 5. The joiner of claim 1, further comprising a removable battery pack coupled to said housing for powering said electric motor.
  • 6. The joiner of claim 1, wherein said forward portion of said housing forms a tubular single piece portion of said housing for housing said electric motor.
  • 7. The joiner of claim 1, wherein said elongated handle portion comprises a two-piece clamshell construction.
  • 8. The joiner of claim 3, wherein said loop portion extends generally parallel with said main portion of said handle.
  • 9. The joiner of claim 1, wherein said housing includes:a rear portion separated from said forward portion by said elongated handle portion, said rear portion extending laterally beyond said forward portion to assist in supporting said housing on a work surface when said joiner is not in use.
  • 10. A joiner comprising:a housing having a forward portion and a handle portion, said handle portion having a trigger switch; an electric motor disposed within said forward portion of said housing, wherein a longitudinal axis of said motor is aligned along a common longitudinal axis with said trigger switch; a battery pack for powering said electric motor; a cutting blade driven by said electric motor; a shoe assembly secured to said forward portion of said housing for housing said cutting blade; and said handle portion of said housing having a stick handle portion which is graspable by a user and offset laterally from said forward portion, to thereby place the fingers of the user approximately along said longitudinal axis of said motor when said user is grasping said handle portion while operating said joiner, to thereby enable said user to apply a force with said hand that is substantially along said longitudinal axis of said forward portion of said housing.
  • 11. The joiner of claim 10, wherein said housing further comprises a loop portion offset laterally from said forward portion of said housing and extending generally parallel to said stick handle portion.
  • 12. The joiner of claim 11, wherein said housing includes a rear portion bridging said loop and stick handle portions, said rear portion further supporting said battery pack thereon.
  • 13. The joiner of claim 12, wherein said battery pack is releasably secureable to said rear portion of said housing.
  • 14. The joiner of claim 10, wherein said stick handle portion of said housing includes a trigger switch engageable by a finger of said user when grasping said stick handle portion.
  • 15. The joiner of claim 10, further including a fence assembly and a forward handle secured to said fence assembly, said forward handle being graspable by one hand of the user when operating said joiner.
  • 16. A joiner comprising:a housing having an elongated forward portion, a stick handle portion and a loop handle portion each extending from said forward portion, at least said stick handle portion being laterally offset from said forward portion, and said stick handle and said loop handle portions being bridged by a rear portion of said housing to form a loop through which the fingers of a user may extend; an electric motor disposed within said forward portion of said housing, wherein a longitudinal axis of said motor is aligned with a longitudinal axis of a trigger switch used to control operation of said motor; and a cutting implement driven by said electric motor.
  • 17. The joiner of claim 16, further comprising:a battery pack releasably secureable to said rear portion of said housing for powering said electric motor.
  • 18. The joiner of claim 16, wherein said stick handle portion includes an ON/OFF trigger for actuating said electric motor.
  • 19. The joiner of claim 16, wherein said stick handle portion is offset laterally a degree sufficient to place the fingers of a user substantially along a longitudinal axis of said forward portion of said housing when said user grips said stick handle portion with one hand.
  • 20. The joiner of claim 16, wherein each of said stick handle portion and said loop handle portion are laterally offset from said forward portion of said housing.
  • 21. A cordless plate joiner comprising:a main housing having opposed ends; an electric motor within the main housing; a cutting blade connected to and driveable by the motor; a shoe assembly connected to one end of the main housing; a handle formed at the second end of the main housing; the handle having a stick handle portion and a loop portion; a battery pack bridging the loop and main portion of the handle; and wherein said motor is aligned longitudinally with said handle of said housing such that a trigger switch disposed on said handle is aligned with a longitudinal axis of said motor.
  • 22. The cordless joiner of claim 21, wherein the housing further comprises a rear portion bridging said stick handle and said loop portions, said battery pack being removably secured to said rear portion.
  • 23. The cordless joiner of claim 21, wherein said stick handle portion is laterally offset from, and extends generally parallel to, said main housing such that when said stick handle portion is gripped by a hand of a user, the fingers of said hand are positioned generally in line with a longitudinal axis extending through a general coaxial center of said main housing.
  • 24. The cordless joiner of claim 21, wherein said stick handle portion includes a forward, rounded portion.
  • 25. The joiner of claim 21, wherein said stick handle portion includes a trigger switch engageable by a finger of said user when said user is grasping said stick handle portion.
  • 26. The joiner of claim 21, further comprising a forward handle secured at or adjacent said first end of said main housing and being graspable with said user's other hand when operating said joiner.
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Non-Patent Literature Citations (1)
Entry
Article in “Woodshop News” concerning Lamello cordless electric plate joiner, dated Oct. 1995.