Control handle support and valve linkage assembly

Information

  • Patent Grant
  • 6557586
  • Patent Number
    6,557,586
  • Date Filed
    Friday, August 25, 2000
    24 years ago
  • Date Issued
    Tuesday, May 6, 2003
    21 years ago
Abstract
A control handle support and valve linkage assembly for use in a lift truck or like vehicle is provided. The assembly includes a first stationary bracket and a second bracket that pivots relative to the first bracket. At least one, and preferably an array of control handles are coupled to the second bracket. A seat deck on the lift truck includes an actuator for engaging a member projecting from the second bracket. When the seat deck is in the closed position, the second bracket is kept in a first, retracted position, and hence, the control handle(s) are kept close to and within the comfortable reach of an operator seated in the adjacent seat. Then, when the seat deck is opened, such as when the operator desires to access a battery compartment or the like, the second bracket, and hence, the control handle(s) automatically and simultaneously pivot or rotate relative to the first stationary bracket. This moves the control handles out of the path of travel of the seat deck to avoid creating any interference. A linkage is also provided for linking each control handle to a valve and a corresponding switch. Together, the valve and switch regulate fluid flow to control one or more aspects of the operation of a carrying assembly or like structure associated with the lift truck.
Description




TECHNICAL FIELD




The present invention relates generally to vehicle control and, more particularly, to an improved assembly for both supporting one or more control handles in a lift truck such that interference with a movable deck or like structure is avoided and linking the control handles to valves for controlling the operation of a carrying assembly forming a part of the lift truck.




BACKGROUND OF THE INVENTION




In a conventional lift truck, an array of control handles are provided for controlling the flow of hydraulic fluid typically used to raise, rotate, or otherwise move a portion of the carrying or lifting apparatus (i.e., the mast and forks and accompanying structures). These control handles should be conveniently located within the operator compartment for easy, comfortable access. Of course, providing control handles that are securely and reliably linked to the corresponding valve(s) for controlling the flow of hydraulic fluid is also an important consideration, as is minimizing the number of parts required and reducing the overall complexity.




Typically, a lift truck is provided with a compartment covered by a movable deck that carries an operator's seat. This compartment usually contains components responsible for providing power to the lift truck, including the battery. In such an arrangement, positioning the control handles comfortably within the reach of the operator generally places them immediately over the seat deck or other movable structure forming a part of the lift truck base. As a result of this placement, the control handles create an obstacle to removing the deck for gaining access to the adjacent battery compartment or the like.




In one prior art truck, before the seat deck can be opened to gain access into the battery compartment, a control handle release mechanism must be actuated followed by the manual pivoting of the control handles away from the seat deck. Such an arrangement is disadvantageous as additional time and effort are required to reposition the control handles prior to opening the seat deck. Further, it requires that an operator be positioned on a side of the truck to which the control handles are located when opening the seat deck. Typically, this side of the truck is opposite to the side that is used when exiting or entering the operator's compartment, resulting in the operator walking around the truck before and/or after opening the seat deck.




In another prior art truck, the control handles, structure which couples the handles to corresponding valves and a front cover, automatically pivot away from the seat deck when the deck is opened. A costly pivoting plate must be provided for mounting the handles, the coupling structure and the front cover. It is also noted that the plate has a low pivot position. Consequently, substantial clearance is required between the floorplate and the front cover, to allow the plate, the control handles, the coupling structure and the front cover to rotate away from the seat deck when the seat deck is raised. This clearance allows the ingress of foreign material onto the hydraulic valves, which is undesirable. Further, the shape of the front cover restricts easy ingress into and egress from the operator's compartment.




Thus, a need is identified for an improved manner for supporting one or more control handles within the comfortable reach of the operator, while at the same time avoiding the creation of interference with removable structures on the lift truck, such as the deck carrying the operator's seat.




SUMMARY OF THE INVENTION




In accordance with a first aspect of the invention, a control handle support and valve linkage apparatus for mounting adjacent a movable deck on a lift truck is provided. The apparatus includes a first stationary bracket and a second bracket in engagement with the first bracket. At least one control handle assembly is coupled to the second bracket, and preferably positioned for easy access by the lift truck operator when seated in the operator's compartment. The second bracket is movable relative to the first bracket between a first retracted position and a second non-interfering position, with the second bracket being in the first position when the deck is in a closed position and in the second position when the deck is moved to an open position. Accordingly, when the seat deck is opened, the second bracket simultaneously pivots to move the control handle assemblies out of the way. This simultaneous pivoting action avoids creating any interference between the control handle assemblies and the seat deck as it is lifted. Further, the pivoting action avoids any interference between the handle assemblies and the battery when the battery is lifted for removal.




In one embodiment, the control handle support and valve linkage apparatus includes a spring for biasing the second bracket relative to the first bracket. The biasing force supplied by this spring allows the second bracket to pivot from the first to the second position when the deck is opened. Preferably, the second bracket rotates through an angle from about 15 degrees to about 90 degrees in moving from the first position to the second position, and most preferably through an angle of about 22°. To provide the desired simultaneous pivoting action and relative movement, the second bracket further comprises a projecting member and the deck includes an actuator. When the deck is moving from the open to the closed position, this actuator engages the projecting member to overcome the spring biasing force and pivot the second bracket to the first position. In a most preferred embodiment, the projecting member is a substantially cylindrical rod and the actuator includes a C-shaped recess for engaging the rod. The deck preferably is at least a portion of a seat deck forming a part of a base portion of the lift truck.




In accordance with a second aspect of the present invention, a control handle support and valve linkage assembly is provided for mounting adjacent to a movable deck on a lift truck having a carrying assembly. The control handle support and valve linkage assembly comprises a first stationary bracket, at least one valve for controlling fluid flow to and away from the carrying assembly on the lift truck, a second bracket engaging the first bracket, at least one control handle assembly coupled to the second bracket, structure for coupling the at least one control handle assembly to the at least one valve, and at least one switch coupled directly to the at least one valve and operable to control fluid flow to the at least one valve. The second bracket is movable relative to the first bracket between a first position when the deck is closed and a second position when the deck is open. Preferably, the coupling structure does not pivot or otherwise move when the second bracket moves between its first and second positions.




Preferably, the control handle support and valve linkage assembly further includes a stationary cover. In one preferred embodiment, the cover has a generally planar outer surface. Advantageously, this planar outer surface does not interfere with the ingress to and egress from the operator's compartment of the lift truck.




In one embodiment, the second bracket rotates relative to the first bracket through an angle of from about 15 degrees to about 90 degrees in moving from the first position to the second position. The second bracket may also rotate through other angular ranges including all ranges subsumed within the range of from about 15 degrees to about 90 degrees. Also, the coupling structure comprises at least one link and at least one cam. The at least one link is coupled to the at least one control handle assembly and the at least one cam. The at least one cam is further coupled to the at least one valve, which preferably comprises a spool valve.




Most preferably, first and second control handle assemblies are provided as part of the control valve linkage assembly. A spring is also provided for biasing the second bracket relative to the first bracket such that the second bracket pivots from the first position to the second position when the deck is moved to the open position. The second bracket includes a projecting member and the deck further comprises an actuator for engaging the projecting member to pivot the second bracket to the first position when the deck is moved to a closed position. In one particular embodiment, the projecting member is a substantially cylindrical rod and the actuator includes a C-shaped recess for engaging the rod. The deck is a seat deck forming a part of a base portion of the lift truck.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is an overall perspective view of a lift truck;





FIG. 2

is a side elevational view of the lift truck of

FIG. 1

;





FIG. 3



a


is the upper portion of an exploded view showing the control handle support and valve linkage assembly of the present invention;





FIG. 3



b


is the lower portion of an exploded view showing the control handle support and valve linkage assembly of the present invention;





FIG. 3



c


is a plan view of the first stationary bracket illustrated in

FIG. 3



a;







FIG. 4

is an enlarged, partially cutaway view of the upper portion of the control handle support and valve linkage assembly of the present invention, with a portion of the cover cutaway to show the connection between the bellcrank secured to each control handle and the corresponding coupling structure;





FIG. 5



a


is a partially cross-sectional, partially cutaway side view showing the second bracket in a first position and taken along view line


5




a





5




a


in

FIG. 4

;





FIG. 5



b


is similar to

FIG. 5



a,


but shows the bracket pivoted to a second position upon the lifting of the seat deck forming a part of the lift truck base; and





FIGS. 6-9

are schematic views, each showing the cam associated with each control handle assembly for actuating a switch that controls the flow of fluid through a corresponding valve.











DETAILED DESCRIPTION OF THE INVENTION




Reference is now made to

FIGS. 1 and 2

, which illustrate a fork lift truck


10


including a control handle support and valve linkage assembly


20


constructed in accordance with the present invention. The truck


10


includes a body


12


housing a battery


140


(see phantom view in

FIGS. 5



a


and


5




b


) for supplying power to a traction motor (not shown) connected to a pair of front drive wheels


12




a


(only one shown in

FIGS. 1 and 2

) and to one or more hydraulic motors (not shown) supplying hydraulic fluid to several different systems, such as mast and fork hydraulic cylinders. The traction motor and the drive wheels


12




a


define a drive mechanism for effecting movement of the truck


10


. An operator's compartment


14


in the body


12


is provided with a steering wheel


16


for controlling the direction of travel of the truck


10


and control handles


30


-


33


(see

FIG. 3



a


) are provided for controlling fork height, tilt, side shift and fork rotation. The steering wheel


16


is coupled via conventional apparatus to a pair of steerable rear wheels


12




b


(only one shown in FIG.


2


).




As best shown in

FIG. 1

, a pair of forks


40


are mounted on a fork carriage mechanism


42


that includes a fork carriage


44


and a load back rest


46


. The forks


40


are coupled to the fork carriage


44


which, in turn, is coupled to an extensible mast assembly


50


. The load back rest


46


is coupled to the fork carriage


44


. The mast assembly


50


includes a fixed lower mast member


52


and nested first and second movable mast members


54


and


56


. The lower mast member


52


is fixedly coupled to the body


12


, while the second movable mast member


56


is coupled directly to the fork carriage


44


. The fork carriage mechanism


42


and the mast assembly


50


together define a fork carrying assembly. The mast assembly


50


includes a plurality of hydraulic cylinders (not shown) for effecting vertical movement of the mast members


54


and


56


. Further, hydraulic cylinders (not shown) are coupled to the body


12


and the mast assembly


50


for tilting mast members


52


,


54


and


56


toward and away from the truck


10


about a substantially horizontal axis. Additional hydraulic apparatus (not shown) is provided between the mast assembly


50


and the carriage mechanism


42


for moving the carriage mechanism


42


and the forks


40


from side to side about a vertical axis A


1


, as well as rotating the carriage mechanism


42


and the forks


40


about an axis of rotation A


2


(see FIG.


2


).




Referring now to

FIG. 3



a,


the control handle support and valve linkage assembly


20


includes the control handles


30


-


33


. The assembly


20


also includes a first generally horizontal stationary bracket


15


and a second, rotatable bracket


11


coupled to the first bracket


15


. The first bracket


15


is fixedly mounted to the body


12


of the lift truck


10


below a seat deck


13


(see

FIG. 4

) and includes a two opposed, inwardly projecting coaxial cantilevered pins


15




a


and


15




d


(see

FIG. 3



c


) extending inwardly from first and second sidewalls


15




b


and


15




c


of the first bracket


15


. The second rotatable bracket


11


includes first and second recesses


11




a


and


11




b


for receiving each of the respective opposing pins


15




a


and


15




d


on the first bracket


15


. Pin


15




d


has a first portion having a first diameter and a second portion having a second diameter which is greater than the first diameter. The second recess


11




b


receives the first portion of the pin


15




d.


When assembled, the second bracket


11


is thus rotatably mounted to the first bracket


15


by virtue of this connection. A spring washer


14




a


is also fitted over pin


15




a


and a spring washer


16




b


is fitted over pin


15




d


to frictionally engage the corresponding sidewalls


15




b,




15




c


of the bracket


15


.




The pin


15




d


further receives a flat washer


17


and a torsion spring


18


. The spring


18


is received on the second portion of the pin


15




d.


The pin


15




d


serves as a hub for the spring


18


that causes the second bracket


11


to pivot relative to the first bracket


15


. More specifically, in the preferred embodiment, a first leg


18




a


of the spring


18


projects downwardly and is received in a recess


150


formed in a cross bar


15




e


of the bracket


15


, while a second leg


18




b


of the spring


18


also projects downwardly and is captured in a C-shaped recess


11




c


provided in the second bracket


11


. As outlined further in the description that follows, the spring


18


effects pivotable movement of the second bracket


11


relative to the first bracket


15


when the seat deck


13


is opened, thereby serving to simultaneously and automatically move the control handles


30


-


33


out of the way to avoid creating interference.




The first control handle


30


is mounted to a first bellcrank


22


via at least one, and preferably a pair of screws


21


. The first handle


30


and the first bellcrank


22


comprise a first handle assembly. The second, third and fourth control handles


31


-


33


are similarly coupled to second, third and fourth bellcranks


27


-


29


via pairs of screws


21


. The control handles


31


-


33


and the bellcranks


27


-


29


comprise second, third and fourth handle assemblies. The term “handle assembly,” as used herein, is also intended to cover a handle when used without accompanying structure such as a bellcrank, or an integral handle/bellcrank unit.




Each bellcrank


22


and


27


-


29


is provided with a bore


23


. Two bushings


24


are press-fit into opposing ends of each bore


23


. A shaft


14




b


passes through each set of two bushings


24


and, hence, through the bores


23


in the bellcranks


22


and


27


-


29


. The shaft


14




b


also passes through bushings


24


press-fit into bores


11




d


and


11




e


in the second bracket


11


. The bellcranks


22


and


27


-


29


and the bushings


24


are rotatable about the shaft


14




b,


and the shaft


14




b


is rotatable relative to the bracket


11


. Spring washers


25


and flatwashers


26


are captured in place by a collar-like spacer


26




a


connected to the shaft


14




b


using a transverse pin


26




b.


The pin


26




b


extends through openings in the spacer


26




a


and shaft


14




b


(the opening in the shaft is not shown).




The first ends


19




a


of first, second, third and fourth links


19


are coupled to the first, second, third and fourth bellcranks


22


and


27


-


29


via retainer pins


23




a


and captivated by cotter pins


23




b,


see

FIG. 3



a.


The opposite, or second ends


19




b


of the first, second, third and fourth links


19


are separately coupled to first ends


60




a


of cams


60


, see

FIG. 3



b.


A separate retainer pin


23




a


and cotter pin


23




b


(only one of each is shown in

FIG. 3



b


) is provided for coupling each link second end


19




b


to its corresponding cam


60


. The second end


60




b


of each cam


60


includes a threaded recess (not numbered) for receiving a threaded upper portion


70




a


of a spool


70


of a corresponding first, second, third or fourth spool valve


72




a


-


72




d.


Hence, pivotal movement of the control handles


30


-


33


and coupled bellcranks


22


and


27


-


29


about shaft


14




b


moves the links


19


, cams


60


and spools


70


generally in a vertical direction.




First, second, third and fourth switches


80




a


-


80




d


are directly coupled to each of the respective spool valves


72




a


-


72




d.


These switches


80




a


-


80




d


are preferably conventional snap-action switches. The switches


80




a


-


80




d


are coupled to the spool valves


72




a


-


72




d


by brackets


82


, spacer plates


84


, insulators


84




a,


retainer plates


86


, and bolts


88


. The retainer plates


86


are provided with tapped holes (not shown) for threadedly receiving the bolts


88


. For each switch


80




a


-


80




d,


a spacer plate


84


and an insulator


84




a


are positioned on opposing sides of the switch. Further, one or more bolts pass through openings provided in the spacer plate


84


, openings in the insulator


84




a,


openings in the switch and openings in the bracket


82


and threadedly engage openings in the retainer plate


86


, which is positioned on a side of the bracket opposite to the side to which the spacer plate, insulator and switch are positioned, for securing the switch to its bracket


82


. The brackets


82


are coupled to the valves


72




a


-


72




d


via bolts


73


.




Referring now to

FIGS. 1 and 4

, a conventional latch


13




a,


coupled to the seat deck


13


, is provided for releasably locking the seat deck


13


to a base portion


12




c


of the body


12


of the lift truck. The seat deck


13


is provided with an actuator, which in the preferred embodiment is a hook


130


having a C-shaped recess (see

FIGS. 5



a


and


5




b


). The hook


130


is fixedly connected to the seat deck


13


such that it does not move relative to the seat deck


13


and is spaced horizontally from the latch


13




a,


see FIG.


4


.




The hook


130


engages a cantilevered pin


11




f


projecting outwardly from the second bracket


11


when the seat deck


13


is in its “down” position so as to maintain the bias spring


18


and second bracket


11


in a first position P


1


relative to the first bracket


15


, see

FIG. 5



a.


When the second bracket


11


is in its first position, generally planar plate portion


11




g


of the bracket


11


is located in a substantially horizontal plane, and the legs


18




a,




18




b


of the spring


18


, which both project downwardly in this preferred embodiment, are moved closer to each other. The seat deck


13


is shown in its “down” position in

FIGS. 1

,


2


,


4


and


5




a


(note dashed line outline of spring


18


).




When the latch


13




a


on the seat deck


13


is manually released (see action arrow C in

FIG. 4

) and the seat deck


13


is pivoted upward (see action arrow A in

FIG. 5



b


), the hook


130


disengages pin


11




f.


An operator may easily release the latch


13




a


when positioned on either side of the truck. Upon removing the substantially downward force of seat deck


13


on pin


11




f,


the spring expands such that leg


18




b


moves away from leg


18




a.


This causes the bracket


11


to rotate (counterclockwise, or in the direction of action arrow B as viewed in

FIG. 5



b


) about pins


15




a


and


15




d


on the bracket


15


to a second position P


2


. When the bracket


11


moves to its second position, the plate portion


11




g


rotates through an angle of about 22° from its substantially horizontal first position (compare

FIGS. 5



a


and


5




b


). Despite this reference to a most preferred degree of angular rotation, it is also contemplated that the plate portion


11




g


could rotate through other angles which fall within the range of from about 15° to about 90° from the first position.




As should be appreciated from viewing

FIG. 5



b,


the control handles


30


-


33


and bellcranks


22


and


27


-


29


rotate with the bracket


11


and, hence, move away from the seat deck


13


. The links


19


, however, do not move relative to the bracket


15


during rotation of the bracket


11


as the bellcranks


22


and


27


-


29


pivot about their retainer pins


23




a


without displacing the links


19


. It is noted that retainer pins


23




a


are substantially coaxial with pins


15




a


and


15




d.


The seat deck


13


may then continue to freely pivoted upwardly, such as to permit the operator to access the battery


140


or other component without contacting or otherwise interfering with the control handles


30


-


33


. Then, when the seat deck


13


moves towards a closed position (i.e., rotates downwardly), and after it has moved past upper ends


30




a


-


33




a


of the handles


30


-


33


, the hook on the seat deck


13


reengages the pin


11




f.


This engagement causes the bracket


11


to rotate against the bias of the spring


18


to its first position P


1


. The locking of the latch


13




a


maintains the bracket


11


in its first position P


1


.




With reference back to

FIG. 3



a,


a stop


112


is preferably provided in this most preferred embodiment to limit the rotational movement effected by the spring


18


of the second bracket


11


relative to first bracket


15


. This stop


112


comprises, for example, a bolt


112




a


threadedly received in a tapped opening


11




h


in the bracket


11


. Rotational movement of the second bracket


11


relative to the first bracket


15


stops when the head of the bolt


112




a


engages the rear wall of first bracket


15


. A nut


112




b


is also provided to lock the bolt


112




a


in position relative to the bracket


11


, as well as to allow for height adjustments.




As shown in

FIGS. 1

,


2


,


4


,


5




a,


and


5




b,


a removable cover


100


is provided over bellcranks


22


and


27


-


29


, links


19


, cams


60


, switches


80




a


-


80




d


and valves


72




a


-


72




d,


but includes slots (not numbered) that allow the lower end portion of the control handles


30


-


33


to pass and engage the corresponding bellcranks


22


,


27


-


29


. This cover


100


is fixedly coupled to the base portion


12




c


of the body


12


and, thus, remains stationary during movement of the bracket


11


between its first and second positions P


1


, P


2


. Due to the compact nature of the brackets


11


and


15


and the mounting of the switches


80




a


-


80




d


directly to the valves


72




a


-


72




d,


the cover


100


has a narrow profile and includes a generally planar outer face


100




a.


Advantageously, this prevents the cover


100


from interfering with the operator's ingress into and egress from the compartment


14


.




In operating the control valve linkage assembly


20


generally, the first control handle


30


is rotated toward the operator causing the spool


70


of the valve


72




a


and its associated cam


60


to be raised. Upward movement of the spool


70


past its centered position opens the valve


72




a


such that hydraulic fluid is permitted to travel to the hydraulic cylinders (not shown) of the mast assembly


50


. The corresponding upward movement of the cam


60


(see action arrow D in

FIG. 6

) causes a roller arm


81




a


of the switch


80




a


to move out of a first groove


60




c


in the cam


60


, which results in the actuation of the first switch


80




a.


Actuation of the switch


80




a


causes a hydraulic pump apparatus (not shown) to supply hydraulic fluid under pressure through the valve


72




a


to the mast assembly


50


. Movement of the control handle


30


away from the operator and to the home or centered position results in the roller arm


81




a


moving back into the groove


60




c


such that the switch


80




a


is no longer actuated. Further movement of the control handle


30


away from the operator results in the valve


72




a


opening to allow hydraulic fluid to drain from the hydraulic cylinders of the mast assembly


50


to a hydraulic reservoir (not shown). As should be appreciated, movement of the control handle


30


away from the operator and beyond its centered position does not result in the switch


80




a


being actuated. Hence, the hydraulic pump apparatus is not actuated when the control handle


30


is moved away from the operator beyond its centered position.




To tilt the mast assembly


50


and the forks


40


, the second control to handle


31


is rotated toward or away from the operator causing the spool


70


of the valve


72




b


and its associated cam


60


to be raised or lowered. Movement of the spool


70


past its centered position opens the valve


72




b


such that hydraulic fluid is permitted to travel between the hydraulic cylinders (not shown) coupled to the body


12


and the mast assembly


50


and a hydraulic pump apparatus (not shown) and a hydraulic reservoir (not shown) for effecting tilting movement of the mast members


52


,


54


and


56


toward and away from the operator. Movement of the cam


60


from its centered position causes a roller arm


81




b


of the switch


80




b


to move out of a second groove


60




d


in the cam


60


resulting in actuation of the second switch


80




b


(see FIG.


7


). Actuation of the switch


80




b


results in the hydraulic pump apparatus supplying hydraulic fluid under pressure through the valve


72




b


to the hydraulic cylinders (not shown) coupled to the body


12


and the mast assembly


50


.




To move the carriage mechanism


42


and the forks


40


from side to side about the vertical axis A


1


, the third control handle


32


is rotated toward or away from the operator causing the spool


70


of the valve


72




c


and its associated cam


60


to be raised or lowered. Movement of the spool


70


past its centered position opens the valve


72




c


such that hydraulic fluid is permitted to travel between appropriate hydraulic cylinders (not shown) provided between the mast assembly


50


and the carriage mechanism


42


and a hydraulic pump apparatus (not shown) and a hydraulic reservoir (not shown) to effect side to side movement of the carriage mechanism


42


and the forks


40


. Movement of the cam


60


from its centered position causes a roller arm


81




a


of the switch


80




c


to move out of a second groove


60




d


in the cam


60


resulting in actuation of the third switch


80




c


(see FIG.


8


). Actuation of the switch


80




c


results in the hydraulic pump apparatus supplying hydraulic fluid under pressure through the valve


72




c


to hydraulic cylinders provided between the mast assembly


50


and the carriage mechanism


42


.




To rotate the carriage mechanism


42


and the forks


40


about an axis of rotation A


2


, the fourth control handle


33


is rotated toward or away from the operator causing the spool


70


of the valve


72




d


and its associated cam


60


to be raised or lowered. Movement of the spool


70


past its centered position opens the valve


72




d


such that hydraulic fluid is permitted to travel between appropriate hydraulic cylinders (not shown) provided between the mast assembly


50


and the carriage mechanism


42


and a hydraulic pump apparatus (not shown) and a hydraulic reservoir (not shown) to effect rotational movement of the carriage mechanism


42


and the forks


40


. Movement of the cam


60


from its centered position causes a roller arm


81




a


of the switch


80




d


to move out of a second groove


60




d


in the cam


60


resulting in actuation of the fourth switch


80




d


(see FIG.


9


). Actuation of the switch


80




d


results in the hydraulic pump apparatus supplying hydraulic fluid under pressure through the valve


72




d


to hydraulic cylinders provided between the mast assembly


50


and the carriage mechanism


42


.




It is further contemplated that the control valve linkage assembly may include only first, second and third control handles (not shown), such as for controlling fork height, side shift, and tilt. Moreover, it is also possible to provide only two control handles (not shown), such as for controlling fork height and tilt. It is additionally contemplated that control handles


32


and


33


may be employed to control options other than fork side shift and fork rotation. For example, the handles


32


and


33


may be used to control the following functions: fork spread (forks traverse left and right symmetrically about the center of the truck); load stabilizer (a pad comes down on the load to keep it from tipping/shifting); push/pull (a device extends out, clamps on a bottom sheet (e.g., cardboard or plastic) and pulls the sheet onto the forks/pushes to remove); clamp (device that clamps the load from the sides); rotate (device that clamps and rotates (e.g., barrels, rolls of paper, etc.) left and right); and upender (device that provides the ability to rotate a load forward and backward (e.g., used for pouring)), or any like function where control of a mechanism associated with a lift truck or other vehicle is provided through the actuation of switches or the like.




The foregoing description of preferred embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled.



Claims
  • 1. A control handle support and valve linkage apparatus for mounting adjacent a movable deck on a lift truck, comprising:a first stationary bracket; a second bracket in engagement with said first bracket; a spring for biasing said second bracket relative to said first bracket; at least one control handle assembly coupled to said second bracket; structure for coupling said at least one control handle assembly to at least one control valve; wherein said second bracket is movable relative to said first bracket between a first position and a second position, said second bracket being in said first position when a portion thereof is engaged as a result of said deck being in a closed position and said second bracket being in said second position when said deck is moved to an open position and a substantial force is no longer being applied against said second bracket portion, and said coupling structure does not substantially change its position so as to substantially influence the position of said at least one valve when said second bracket moves between its first and second positions.
  • 2. An apparatus as set forth in claim 1, wherein said spring biases said second bracket toward said second position and effects movement of said second bracket to said second position when said deck is moved to the open position.
  • 3. An apparatus as set forth in claim 1, wherein said second bracket rotates through an angle from about 15 degrees to about 90 degrees in moving from the first position to the second position.
  • 4. An apparatus as set forth in claim 1, wherein said second bracket portion comprises a projecting member and said deck further comprises an actuator for engaging said projecting member to pivot said second bracket to said first position when said deck is in a closed position.
  • 5. An apparatus as set forth in claim 4, wherein said projecting member is a substantially cylindrical rod and said actuator includes a C-shaped recess for engaging said rod.
  • 6. An apparatus as set forth in claim 1, wherein the deck is at least a portion of a seat deck forming a part of a base portion of the lift truck.
  • 7. An apparatus as set forth in claim 1, wherein said coupling structure comprises at least one link and at least one cam, said at least one link being coupled to said at least one control handle assembly and said at least one cam, and said at least one cam being further coupled to said at least one valve.
  • 8. A control handle support and valve linkage assembly as set forth in claim 1, wherein the deck is a seat deck forming a part of a base portion of the lift truck.
  • 9. A control handle support and valve linkage assembly mounted adjacent to a movable deck on a lift tuck including a carrying assembly, comprising:a first stationary bracket; at least one valve for controlling the flow of a fluid to and away from the carrying assembly on the lift truck; a second bracket engaging said first bracket; a spring for biasing said second bracket relative to said first bracket; at least one control handle assembly coupled to said second bracket; structure for coupling said at least one control handle assembly to said at least one valve; and wherein said second bracket is movable relative to said first bracket between a first position and a second position, said second bracket being in said first position when a portion thereof is engaged as a result of said deck being in a closed position and said second bracket being in said second position when said deck is moved to an open position and a substantial force is no longer being applied against said second bracket portion, and said coupling structure does not substantially change its position so as to substantially influence the position of said at least one valve when said second bracket moves between its first and second positions.
  • 10. A control handle support and valve linkage assembly as set forth in claim 8, further comprising a stationary cover.
  • 11. A control handle support and valve linkage assembly as set forth in claim 10, wherein said stationary cover has a generally planar outer surface and said lift truck has an operator's compartment, whereby said planar outer surface does not interfere with ingress to and egress from said operator's compartment.
  • 12. A control handle support and valve linkage assembly as set forth in claim 9, wherein said second bracket rotates through an angle of from about 15 degrees to about 90 degrees in moving from the first position to the second position.
  • 13. A control handle support and valve linkage assembly as set forth in claim 9, wherein said coupling structure comprises at least one link and at least one cam, said at least one link being coupled to said at least one control handle assembly and said at least one cam, and said at least one cam being further coupled to said at least one valve.
  • 14. A control handle support and valve linkage assembly as set forth in claim 9, further comprising at least one switch coupled directly to said at least one valve and being operable to control fluid flow to said at least one valve.
  • 15. A control handle support and valve linkage assembly as set forth in claim 9, wherein said at least one valve comprises at least one spool valve.
  • 16. A control handle support and valve linkage assembly as set forth in claim 9, wherein said at least one control handle assembly comprises first and second control handle assemblies.
  • 17. A control handle support and valve linkage assembly as set forth in claim 16, wherein each said control handle assembly comprises a control handle and a bellcrank, said control handle being fixedly coupled to said bellcrank.
  • 18. A control handle support and valve linkage assembly as set forth in claim 9, wherein said spring biases said second bracket toward said second position and effects movement of said second bracket to said second position when said deck is moved to the open position.
  • 19. A control handle support and valve linkage assembly as set forth in claim 9, wherein said second bracket portion comprises a projecting member and said deck further comprises an actuator for engaging said projecting member to cause said second bracket to move to said first position when said deck is moved to its closed position.
  • 20. A control handle support and valve linkage assembly set forth in claim 19, wherein said projecting member is a substantially cylindrical rod and said actuator includes a C-shaped recess for engaging said rod.
  • 21. A lift truck comprising:a movable deck; and a control handle support and valve linkage apparatus mounted adjacent to said movable deck and comprising a first stationary bracket; a second bracket in engagement with said first bracket at least one control handle assembly coupled to said second bracket; structure for coupling said at least one control handle assembly to at least one control valve; wherein said second bracket is movable relative to said first bracket between a first position and a second position, said movable deck engaging a portion of said second bracket during movement of said deck to a closed position so as to effect movement of said second bracket to a first position, said second bracket being moved to said second position when said deck is moved to an open position and a substantial force is no longer being applied against said second bracket portion, and said coupling structure does not substantially change its position so as to substantially influence the position of said at least one valve when said second bracket moves between its first and second positions.
  • 22. A lift truck as set forth in claim 21, wherein said second bracket further comprises a projecting member and said deck further comprises an actuator for engaging said projecting member to cause said second bracket to move to said first position when said deck is moved to its closed position.
  • 23. A lift truck as set forth in claim 21, wherein said deck is at least a portion of a seat deck forming a part of a base portion of the truck.
Parent Case Info

This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/151,118, filed Aug. 27, 1999, entitled “Control valve linkage assembly,” which is incorporated herein by reference.

US Referenced Citations (10)
Number Name Date Kind
2861593 Bowman Nov 1958 A
3492889 Hauff Feb 1970 A
4051860 Dowd et al. Oct 1977 A
4054083 Utter Oct 1977 A
4074690 Adams et al. Feb 1978 A
4140144 Dowd et al. Feb 1979 A
4310026 Oliver et al. Jan 1982 A
4526204 Primdahl Jul 1985 A
4660730 Holmes Apr 1987 A
5138756 Johnson et al. Aug 1992 A
Foreign Referenced Citations (1)
Number Date Country
9013863 Nov 1990 GB
Non-Patent Literature Citations (2)
Entry
Page 7 of a Yale Brochure published in Apr., 1994.
4 pages illustrating and listing parts for a European Crown lift truck, published mid-1995.
Provisional Applications (1)
Number Date Country
60/151118 Aug 1999 US