Joy stick

Information

  • Patent Grant
  • 6667734
  • Patent Number
    6,667,734
  • Date Filed
    Wednesday, July 11, 2001
    23 years ago
  • Date Issued
    Tuesday, December 23, 2003
    21 years ago
Abstract
A first crank supports an operating stick so as to be pivotable in a first direction. First flat faces are formed at lower both end portions in the first direction of the first crank. A second crank supports the operating stick so as to be pivotable in a second direction which is perpendicular to the first direction. Second flat faces are formed at lower both end portions in the second direction of the second crank. A restoration member is arranged coaxially with the operating stick which is situated at a neutral position thereof. The restoration member includes a flat top face brought into contact with the first flat faces and the second flat faces. A spring member is arranged coaxially with the restoration member, and urges the restoration member toward the first flat faces and the second flat faces.
Description




BACKGROUND OF THE INVENTION




The present invention relates to a joy stick, and more particularly to the joy stick in which restoring accuracy of cranks arranged in a casing has been enhanced.




An example of a related joy stick of this type will be described referring to

FIGS. 9 and 10

. In the drawings, a joy stick


1


is composed of a base table


2


, a helical spring


3


and a spring holder


4


mounted on the base table


2


in this order, a cam


5


received in a recess


4




a


formed on an upper face of the spring holder


4


, and an operating stick


6


attached to the cam


5


at its lower part, and a box-like casing


7


which is open at its lower face and attached to the base table


2


at its lower end part.




In the casing


7


, there is disposed a lower crank


8


. Shafts


8




a


projecting from both ends of the lower crank


8


are rotatably engaged in axial bores which are formed in a left side plate


7




a


and a right side plate


7




b


of the casing


7


.




The lower crank


8


is provided in its central area with a hole


8




b


through which the cam


5


is adapted to be idly inserted. A pin


9


is passed through the lower crank


8


and the cam


5


so that the lower crank


8


and the cam


5


can freely pivot in a direction of an arrow X around the pin


9


. Therefore, the spring holder


4


is biased upward by the helical spring


3


, and accordingly, the cam


5


and the lower crank


8


are always pressed upward by the spring holder


4


.




Moreover, an upper crank


10


which perpendicularly intersects the lower crank


8


is disposed in the casing


7


. Shafts


10




a


projecting from the upper crank


10


in a direction to the back and the forth in the drawing are rotatably engaged in axial bores (not shown) which are formed in a front side plate (not shown) and a back side plate


7




c


of the casing


7


.




In a central area of the upper crank


10


, there is formed a guide groove


10




b


in which the operating stick


6


is idly engaged so as to be pivotable in the direction of the arrow Y. In addition, a variable resistor


11


for detecting rotation angles of the lower clank


8


is provided on an outer face of the left side plate


7




a


of the casing


7


. A rotary shaft (not shown) of the variable resistor


11


is coupled to the left hand shaft


8




a


of the lower crank


8


.




In the same manner, a variable resistor (not shown) for detecting rotation angles of the upper clank


10


is provided on the back side plate


7




c


of the casing


7


, and the variable resistor is coupled to one of the shafts


10




a


of the upper crank


10


.




In the joy stick constructed in this manner, by operating the operating stick


6


in the direction of the arrow Y, the lower crank


8


is rotated as indicated by an arrow A, and the rotation angles are detected by the variable resistor


11


thereby controlling an object to be controlled.




Similarly, by operating the operating stick


6


in the direction of the arrow X, the upper crank


10


is rotated, and the rotation angles are detected by the variable resistor. In conducting these operations, when the operating stick


6


is tilted to the left, for example, as shown in

FIG. 10

, the spring holder


4


is pressed by the cam


5


which rotates along with the operating stick


6


, and thus, the helical spring


3


will be compressed.




When the operating stick


6


in this state is released by an operator's finger, the operating stick


6


will be restored to a neutral position as shown in

FIG. 9

, along with the cam


5


by resilient restoring force of the helical spring


3


. When the lower crank


8


is rotated by operating the operating stick


6


in the direction of arrow Y, the operating stick


6


will act in the same manner.




In addition to a problem of the above described joy stick


1


that the guide groove


10




b


of the upper crank


10


may be worn by repeated operations of the operating stick


6


, but there is also a problem that the restored position of the upper crank


10


may change due to a backlash or a clearance between components in terms of accuracy, and the variable resistor


11


may not be accurately restored to the determined neutral position, resulting in inaccurate output of the control of the joy stick


1


.




SUMMARY OF THE INVENTION




It is therefore an object of the present invention is to provide a joy stick which is excellent in restoring accuracy of the cranks to the neutral position and free from such confusion in the control.




In order to achieve the above object, according to the present invention, there is provided a joy stick, comprising:




an operating stick;




a first crank, which supports the operating stick so as to be pivotable in a first direction;




first flat faces, which are formed at lower both end portions in the first direction of the first crank;




a second crank, which supports the operating stick so as to be pivotable in a second direction which is perpendicular to the first direction;




second flat faces, which are formed at lower both end portions in the second direction of the second crank;




a restoration member, which is arranged coaxially with the operating stick which is situated at a neutral position thereof, the restoration member including a flat top face brought into contact with the first flat faces and the second flat faces; and




a spring member, which is arranged coaxially with the restoration member, the spring member urging the restoration member toward the first flat faces and the second flat faces.




In this configuration, the restoration member is biased upward by the spring member, thus enabling the first crank and the second crank to be accurately restored to the neutral position. Therefore, irrespective of wear of the first crank and the second crank, the restoring accuracy of the first crank and the second crank can be maintained. At the same time, the number of the components will be decreased, thus attaining a low manufacturing cost.











BRIEF DESCRIPTION OF THE DRAWINGS




The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein like reference numerals designate like or corresponding parts throughout the several views, and wherein:





FIG. 1

is a longitudinal sectional view showing one embodiment of a joy stick according to the invention;





FIG. 2

is an exploded perspective view of the joy stick;





FIG. 3

is a partially-exploded perspective view of the joy stick;





FIG. 4A

is a back side view of a base table incorporated in the joy stick;





FIG. 4B

is a left side view of the base table;





FIG. 4C

is a plan view of the base table;





FIG. 4D

is a right side view of the base table;





FIG. 4E

is a front view of the base table;





FIG. 4F

is a sectional view taken along a line F—F of FIG.


4


C.





FIG. 5A

is a plan view of a first crank incorporated in the joy stick;





FIG. 5B

is a front view of the first crank;





FIG. 5C

is a right side view of the first crank;





FIG. 6A

is a plan view of a second crank incorporated in the joy stick;





FIG. 6B

is a front view of the second crank;





FIG. 6C

is a right side view of the second crank;





FIG. 6D

is a bottom view of the second crank;





FIG. 7A

is a detailed view of a spring holder incorporated in the joy stick;





FIG. 7B

is a sectional view taken along a line G—G of

FIG. 7A

;





FIG. 8

is a detailed view showing an operating stick incorporated in the joy stick;





FIG. 9

is a longitudinal sectional view of a related joy stick; and





FIG. 10

is a longitudinal sectional view showing operation of the related joy stick.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Now, one embodiment of the joy stick according to the invention will be described in detail referring to the accompanying drawings. As shown in

FIGS. 1 and 2

, a joy stick


20


includes a base table


22


fitted to an open side of a casing


21


, a first crank


23


and a second crank


24


perpendicularly intersecting with each other and disposed in the casing


21


. A spring holder


26


is pressure contacted to respective lower faces of opposite end parts of the first crank


23


and the second crank


24


. A helical spring


27


is interposed between the spring holder


26


and a groove


25


formed in the base table


22


(see

FIGS. 4A

to


4


F).




The first crank


23


has shafts


28


projecting from both ends thereof as shown in

FIGS. 5A

,


5


B and SC and rotatably engaged in axial bores


30


A,


31


A formed in side plates


29


A,


29


B of the casing


21


as shown in FIG.


3


. In the same manner, the second crank


24


has shafts


33


projecting from both ends thereof as shown in

FIGS. 6A

,


6


B,


6


C and


6


D and rotatably engaged in axial bores


31


B,


31


B formed in left and right side plates


29


C,


29


D of the casing


21


as shown in FIG.


3


.




The first crank


23


is further provided with arm portions


32


at base ends of the shafts


28


, and flat face portions


32




a


are formed on lower faces of the arm portions


32


. In the same manner, the second crank


24


is provided with arm portions


34


at base ends of the shafts


33


, and flat face portions


35


are formed on lower faces of the arm portions


34


. The spring holder


26


is resiliently abutted against these flat face portions


32




a,




35


by means of the helical spring


27


. Further, as shown in

FIGS. 7A and 7B

, an annular groove


36


is formed at a lower face of a circumferential part of the spring holder


26


to idly receive the helical spring


27


.




As shown in

FIGS. 6A

to


6


D, the second crank


24


is provided with a connecting portion


37


for coupling the arm portions


34


. A shaft


38


is provided at a center of the connecting portion


37


, and an arcuate groove


39


is formed around an outer circumference of the shaft


38


. A groove


41


and a head


42


formed at a distal end of an operating stick


40


(see

FIG. 8

) are engaged with the shaft


38


and the groove


39


, and at the same time, an arm portion


43


of the operating stick


40


passes through a guide groove


45


formed between guide portions


44


of the first crank


23


, and projects upward through a stick hole


31


C formed in an upper plate


29


of the casing


21


.




One of coupling portions


46


shown in

FIGS. 1 and 6A

to


6


D is coupled to a variable resistor


47


. Similarly, one of coupling portions


48


shown in

FIGS. 5A

to


5


C is connected to a variable resistor (not shown).




Now, operation of the joy stick


20


will be described. As shown in

FIG. 1

, the operating stick


40


is grasped and tilted to the left and the right in a direction of an arrow B (or an arrow D in

FIG. 3

) thereby to rotate the first crank


23


, and the angle of the rotation is detected by the variable resistor (not shown). In the same manner, the operating stick


40


is tilted back and forth in a direction of an arrow C (or an arrow E in

FIG. 3

) thereby to rotate the second crank


24


, and the angle of the rotation is detected by the variable resistor


47


.




By releasing the grasp of the operating stick


40


, the first crank


23


and the second crank


24


are restored to a neutral position as shown in

FIG. 1

by resilient restoring force of the helical spring


27


. On this occasion, the spring holder


26


which swings following compressive restoring action of the helical spring


27


always resiliently abuts against the flat face portions


32




a


of the first crank


23


and the flat face portions


35


of the second crank


24


respectively to rotate the first crank


23


and the second crank


24


. Therefore, an angle of the restoration will be constant, irrespective of engaging accuracy or progress of wear of the first crank


23


and the second crank


24


with respect to the operating stick


40


.




In the meantime, the cams and pins which have been incorporated in the related joy stick are not required for assembling the joy stick of the present invention, and further, because the assembling work can be conducted from only one direction as shown in

FIG. 2

, the joy stick can be easily assembled and number of the components will be decreased.




When manufacturing the components, because the engaging accuracy and wear of the first crank


23


and the second crank


24


with respect to the operating stick


40


will not badly affect the restoring accuracy, it will be possible to loosen the engaging accuracy, and production and quality control will be made easier. Further, because the spring holder


26


and the flat face portions


32




a,




35


are tightly brought into face-to-face contact with each other and will not slide, it will be possible to improve operability of the operating stick


40


. Thus, it will be possible to decrease the resilient restoring force of the helical spring


27


, and the joy stick


20


can be made compact as small as possible.




Although in the above described embodiment, the invention has been described referring to an example in which the variable resistors are employed as detecting means for detecting the rotation angles of the upper and the lower cranks, the detecting means should not be restricted to the variable resistor, but may be an encoder of a rotary type, for example.




Although the present invention has been shown and described with reference to specific preferred embodiments, various changes and modifications will be apparent to those skilled in the art from the teachings herein. Such changes and modifications as are obvious are deemed to come within the spirit, scope and contemplation of the invention as defined in the appended claims.



Claims
  • 1. A joy stick, comprising:an operating stick having at its distal end a head with a groove; a first crank; having a guide groove which supports the operating stick so as to be pivotable in a first direction; first flat faces, which are formed at lower both end portions in a second direction perpendicular to the first direction; a second crank; having a groove and a shaft which supports the operating stick so as to be pivotable in the second direction, the groove in the distal end of the operating stick engaging the shaft of the second crank; second flat faces, which are formed at lower both end portions in the first direction; a restoration member, which is arranged coaxially with the operating stick which is situated at a neutral position thereof, the restoration member including a flat top face brought into contact with the first flat faces and the second flat faces; and a spring member, which is arranged coaxially with the restoration member, the spring member urging the restoration member toward the first flat faces and the second flat faces.
  • 2. The joy stick of claim 1, wherein the restoration member further has an annular groove formed in a lower face and the spring member is retained in the annular groove of the restoration member.
  • 3. The joy stick of claim 1, wherein the second crank is provided with a connecting portion coupling both end portions, the shaft being provided at a center of the connecting portion, and an arcuate groove being formed in the connecting portion around an outer circumference of the shaft, the head at the distal end of the operating stick being received in the arcuate groove.
Priority Claims (1)
Number Date Country Kind
P.2000-212931 Jul 2000 JP
US Referenced Citations (3)
Number Name Date Kind
6353430 Cheng et al. Mar 2002 B2
6445377 Shimomura Sep 2002 B1
6538639 Takahashi Mar 2003 B1