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Publication numberUS3168157 A
Publication typeGrant
Publication dateFeb 2, 1965
Filing dateMay 10, 1963
Priority dateMay 10, 1963
Also published asDE1480655A1
Publication numberUS 3168157 A, US 3168157A, US-A-3168157, US3168157 A, US3168157A
InventorsUlinski Bronislaus I
Original AssigneeYale & Towne Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Controller
US 3168157 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

B. l. ULINSKI CONTROLLER 2 Sheets-Sheet 1 Filed may 1o, 196s 9 w mw w Mw w wf n um mw W/M A i if l l l/. f ,n /f I I l Il w B. l. ULlNSKl Feb. 2, 1965 CONTROLLER 2 Sheets-Sheet 2 Filed May 10, 1965 RM y E O VM H WZ f A f United States Patent C) 3,168,157 CNTRLLER Bronislaus l., lllinslri, Flossrnoor, lll., assigner, ey rnesne assignments, to Yale de rlCowne, Inc., New Yorlr, NX., a company ot hio Filed May 19, 1963, Ser. No. 279,512 Claims. (Ci. 18h-65) This invention relates to a controller for a so-called walkie type industrial truck, although it will be readily appreciated that certain features of the invention may be used in other types of controllers. As a particular feature of my invention, the entire controller including the resistors, is housed within a handle, the handle being of that type that is pivoted on the traction unit of a Lwalkie7 type truclr for controlling the direction and speed of the truck.

As a further particular feature of the invention, contacts are applied to certain of the resistors, the bringing together' of the contacts having the effect of shunting resistances from the traction circuit. As a particular feature of this portion of the invention, the resistors are Within the handle, are insulated therefrom, and are adapted to receive circulating air whereby to remain adequately cool.

As a further feature of the invention, the shunting of the resistors is accomplished by rotation of a simple control member mounted on the outer end of the handle, with the resistances being shunted out of the traction circuit in a particular sequence to provide the desired variations in speed, regardless of the direction of rotation of the control member, Further, directional switch means are provided which are also controlled by rotation of the control member, with rotation of the control member in one direction trst actuating the directional switch means to close a traction circuit in one direction and then shunting out the resistors in the desired sequence to increase the speed of the truck in that direction, and rotation of the control member in the opposite direction irst actuating the directional switch means to close a traction circuit in the opposite direction, and then shunting out the resistors in the desired sequence to increase the speed of the truck in the opposite direction.

Thus, through simple operating means, as will be set forth in my specification, l am able to effect the closing of a forward or rearward directional circuit and the sequential shunting o resistances out of the circuit in a most effective manner.

Other objects and advantages of invention will become apparent from the following description when read in conjunction with the accompanying drawings wherein:

FIG. 1 is a perspective view of an industrial truck incorporating a controller' constructed in accordance with the invention;

FIG. 2 is a sectional view taken on the line 2-2 of FIG. l;

PEG. 3 is a sectional view talicn on the line 3-3 of FIG. 2;

FlG. 4 is a sectional view taken on the line 4-4 of FIG. 3;

FlG. 5 is a sectional view or" a hand grip through which the controller is actuated;

FIG. 6 is a perspective view partly in section of parts of the controller and hand grip, showing the connection of the hand grip with the controller;

FlG. 7 is a perspective View showing a slightly dilerent form of rotatable control member mounted on the outer end of the handie for actuating the controller; and

HG. 8 is a sectional view of the rotatable control member shown in FIG. 7.

Referring to the drawings and in particular to FIG. l,

Cil

there is shown an industrial truck 10 of the so-called walkie type incorporating a controller constructed in accordance with the invention. While the particular truck shown in the drawing is of the type shown in my United States Patent No. 2,956,776, it will be appreciated that the controller of the invention may be used in other types and styles of industrial trucks.

The particular details of the construction of the truck form no part of the invention and it is surllcient to an understanding of the invention to merely point out that the trucl; 1t? includes a main frame 11, which is supported on a steerable traction wheel 12, and an elevating frame 13, which is supported at one end for vertical movement on the main frame 11 and Supported at the other end by rollers 14, which pivot downwardly during elevating of the frame 13. ln utilizing the truck, the elevating frame 13, while in a lowered position as shown in FIG. 1, is inserted through a loaded pallet and then elevated to lift the loaded pallet from the ground to permit transporting thereof through operation of the truck.

As previously pointed out, the wheel 12 which supports the main frame 11, is both a steering and traction wheel, and to this end, the wheel 12 is mounted for steering rotation about a vertical axis on the main frame 11 and is adapted to be driven by a battery operated electric motor 15. The motor 15 is connected to the wheel 12 through a suitable transmission and rotates with the wheel 12 during steering of the wheel. The combination of the wheel 12 and the drive motor 15, together with the transmission, is commonly referred to as a combined steering and traction unit. Energy for driving the motor 15 is provided by batteries 16, enclosed in a suitable housing l? on the main frame 11.

The combined steering and traction unit formed by the wheel 12 and the motor 15 is conveniently steered by a steering handle i8 which is pivotally attached at its lower end to the unit by a horizontal pivot 1g, so that the handle may be pivoted in a vertical direction to a position which is convenient for the operator to swing the handle 18 either to the left or to the right to effect rotation of the wheel 12 to steer the truck.

ln accordance with the invention, the handle 18 is of hollow construction and the controller, generally indicated at 2t) in FG. l, for controlling the direction of operation and speed of the drive motor 15 is mounted within the hollow handle 18.

As best shown in FIGS. 2 and 3, the handle 18 is conveniently formed of an elongated channel 21, with the normally open side of the channel closed by a cover plate 22. As shown in FIG. 3, the cover plate 22 terminates short of the lower end of the channel 21 of the handle 18 and is provided with vertically spaced openings 23 whereby air may circulate as indicated by the arrows in FIG. 3 to provide cooling of the controller 20.

The controller 2t) includes a channel shaped frame 24, and the controller is mounted within the channel 21 of the handle 18, in spaced relationship to the inner surfaces of the channel 21, by bolts 25, 26 and 27 and spacer bushings 28, 29 and 3).

The controller 2t), in the form shown in the drawings, includes two elongated resistor strips 31 and 32. The strip 31 extends up and around an insulator 33 and the strip 32 extends up and around an insulator 34. The insulator 33 is supported on a screw 35, while the insulator 34 is supported on a screw 36. The strips 31 and 32 are held spaced and electrically insulated from the controller frame 24 by an insulator strip 37 carried by and extending between the ends of the screws 35 and 36, and by insulator strips 33 and 39 carried by and extending between the screws 35 and 36 between the insulators 33 and 34 and the controller frame 24.

A laminated terminal block lit) having laminations al, 42, 43, 44 and l5 of suitable insulating material is secured to a flange of the controller frame 24 by means of through bolts 46 and 47, and one .end of the resistor strip 3l, the upper end otra spring contact linger d and one end of a connector strip 49, best shown in FlG. 4, are clamped in electrical contact between the laminations 4l and 42.

The other end of the strip 3l, the upper end of a second spring contact ringer Si) and one end of the resistor' strip 32 are clamped in electrical contact between the laminations 42 and 43. The other end of the resistor strip 32. andthe upper end of a bus bar l are clamped in electrical contact between the laminations 43 and t, and the upper end of a second bus bar 52 and the opposite end of the connector strip 49 are connected between the laminations de and 45.

An .electric cable 53 having a terminal end 54 is connected to the lower end of the bus bar 5l and a cable 55 having aterminal end 56 is connected to the lower end of the bus bar 52 by means of a through bolt 57 which is insulated from the terminals Srl, 56 and also from the bus bars51 and 52 bybushings SS and a washer 59 formed of insulating material. The cables 53 and 55 form part of the traction circuit through which current is applied to the drive 15.

With the arrangement as so far described, and with the spring contact lingers 4S and Sil in the position shown in FIG. 2, current may iiow from the cable 53 through the bus bar 5l. through the strip 32, through the strip 3l, through the connector strip 49 and through the bus bar 52 to the cable 55'. Thus in the position of the contact lingers 4S and 5t), both the resistor strips 31 and 32 are connected in the circuit to provide maximum resistance and maximum voltage drop, whereby slow speed operation of the drive motor l5 is obtained through the traction circuit to the motor l5.

It however, the spring contact linger 4S is flexed so that the lower end lila thereof makes electrical contact with the lower end Sila oi the contact-linger 56, it will be appreciated that the resistance strip 3l will be shunt-ed out of the circuit, so that current from the cable 53 will liow only through bus bar 5l, resistor 32, contact linger dii, contact linger 4S, connector strip 4&9 and bus bar 52. Thus, the voltage on the drive motor l5 will be increased with resulting increase in the speed of the motor l5.

It the contact linger i8 is further iiexed so as to not only move the lower end 48a thereof into electrical contact with the lower end 59a of the spring contact linger Sti but also to flex the spring contact linger Si) to move the lower end Stia thereof into electrical contact with a contact 51a on the bus bar 5l, both resistance strips 3l and 32 will be shunted out of the circuit, so that current will iiow from cable 53 through bus bar 5l, Contact linger Sii, contact lfinger 48, connector strip i9 and bus bar 52. The voltage on the drive motor therefore will be further increased with further increase in speed of the drive motor 15. Thus, through controlled movement or ilexing of the contact Vingers 48 and Sii, the voltage applied lto the drive vmotor may be increased in three steps to provide three speeds ofthe drive motor.

Yin the controller as illustrated, such controlled move ment or iiexing or the contact fingers i8 or Sil is etiected through .rotation or pivoting of a pair of bell crank members 6l in a clockwise direction, as viewed in FiG. 2, about a pivot pin 62. The pivot pin 62 extends through a block 60 of insulating material, and the block 6G is connected to the controller trame 24 by a through bolt 63 which extends through the bus bars 5l and 52 and is suitably insulated therefrom by bushings 64.

As the bell crank members 6l are rotated in the clockwise direction, a roller 65 mounted on a pivot 66, extending between and secured to the bell crank members 6l, contacts the lower end 48a of the spring contact linger -s to trex the linger 48 and move the lower end d8a thereot into contact with the end Stia ot the spring contact linger 5G. On further rotation of the bell crank members 6l in the clockwise direction, the roller 65 tienes both the linger 48 and the linger 5t) to move the end Stic of linger Sti thereof into contact with the contact Sla of the bus bar 5l. Rotation of the members 6l' in the counterclockwise direction is limited by engagement of the roller 65 with the upper surface of the block 6h, as shown in FlS. 2.

A block 67 or rigid insulating material is positioned between and is pivotally connected to the bell crank members 6l by pivots 68, and a pair of spaced vertically extending operating rods 69 and 70, best shown in 6, extend slidably through the block 67. The rod 6@ has an enlarged end member 7l secured to the lower end thereof and the rod 7d has an enlarged end member 72 secured to the lower end thereof. A lost motion connection is thus provided between the rods 69 and '7th and the block 67 so that upward movement of either rod 69 or 7u effects upward movement of the block 67 and therefore clockwise rotation of the hell crank members 6i through contact of either the enlarged member 7l or 72 with the lower surface or the insulating bloeit 67, while downward movement of either rod 6% or 7th is ineffective to move the block 67.

As best shown in FlG. 6, the upper ends oi the rods 6@ and 7i) are pivotally connected through pivots 73 and 74 to a block which is secured, as best shown in FlG. 5, to a center portion 76 of a hand grip 77 by means of bolts 7S and 79. The hand grip .77 is rotatably mounted in the upper end ot the handle i3 through suitable bearings titl and Si, shown in FlG. 5, and extends transversely from each side of the upper end of handle i8 whereby it may be easily gripped by the operator of the truck. As best shown in FIG. 6, the pivots 73 and 74 are eccentric to the axis of rotation of the hand grip 77 so that when the hand grip 77 is rotated in the direction of the arrow A in FlG. 6, the rod 69 is moved downwardly and the rod 7d is moved upwardly so that the insulating block 67 is also moved upwardly through contact of the enlarged end member 72 of the rod 7i? with the lower surface of the block 67 causing clockwise rotation of the bell crank members 6l to sequentially shunt out the resistors Si and 32 as previously described.

lf the handle grip 7'7 is rotated in the opposite direction from the arrow A, the rod 69 will be moved upwardly and the rod 7i? moved downwardly. On upward movement of the rod 69, the insulator block 67 is also moved upwardly through engagement of the enlarged end member 71 on the rod 69 with the lower surface of the insulator block 67, so that upward movement of the rod 69 also effects rotation of the bell crank members 6l to sequentially shunt out the resistors 3l and 32. Thus on either direction of rotation of the hand grip 77, the resistor strips 3l and 32 are sequentially shunted out.

When the hand grip 77 is released after rotation, the hand grip, rods 69 and 7i?, and the bell crank members 6l are returned to their initial position as shown in FIGS. 2 and 6 by means of a spring 82 which is compressed through upward movement of the insulator block 67 by the upward movement of rod 69 or 7i?. The spring 62 surrounds the rods 69 and "itl and bears at its upper end against a spring seat 83 which is held against upward Vmovement by an angle plate 8d which is secured to the laminated insulator block lll by the screws 46 and 47. The spring S2 bears at ythe lower end against a spring seat d5 which rests on the upper surface of the insulator- :block 67. Thus, the insulator block 67 is normally urged by the spring S2 in the downward direction toward the position shown in FlG. 2.

As a feature of the invention, the upward movement ot either rod 69 or iii also closes either a forward or rearward traction circuit. To this end, an angle plate 36 of suitable electrically conducting material is secured to the bus bar Si and carries a pair of contacts S7 and SS, best shown in FiG. 3. A terminal block 69 or suitable insulating material is also secured to the bus bar 51 below the angle plate 86 by means of a bolt 9) which extends through the bus bars 51 and 52 and is insulated therefrom by an insulating bushing 91. A pair of spring fingers 92 and 93 are secured to the upper surface of the terminal block S9 through terminal screws 94 and 95. The spring nger 92 has a contact 96 adapted to make contact with the Contact 87 and the spring linger 93 has a Contact 97 adapted to make contact with the contact 83.

As best shown in FIG. 6, the enlarged end member 71 of the rod 69 engages the outer end of the spring linger 92 and the enlarged end member 72 of the rod 70 engages the outer end of the spring linger 93, and when the rods 69 and 70 are in the position shown in FIGS. 2 and 6, the contacts 96 and 97 are held out of contact with the contacts 87 and SS. When, however, the hand grip 77 is rotated in the direction of the arrow A in FlG. 6 to raise the rod 79, the pressure on the spring finger 93 is relieved whereby contact 97 engages the contact 8S. At the same time, downward movement of the rod 69' exes the spring linger 92 downwardly to move the contact 96 further away from the contact S7. If on the other hand, the hand grip is rotated in the opposite direction to move the rod 69 upwardly and the rod 7@ downwardly, the contacts 96 and 87 will close while the contact 97 will be moved urther from the contact 88.

Thus in one direction of rotation of the hand grip 77', the contacts 88 and 97 will close and in the other direction of rotation ot the hand grip 77, the contacts 87 and 96 will close. The terminal screws 94 and 9S extend through the terminal block 89 whereby electric cables, no shown, leading from the relays or contactors of a conventional reversing switch for the drive motor 15, may be attached, so that closing of contacts 88 and 97 will condition the traction circuit for operation of the drive motor in one direction and closing of the contacts 87 and 96 will condition the traction circuit for driving the motor in the opposite direction.

The relative dimensions of the parts of the controller are such that initial rotation or the hand grip 77 in the direction of the arrow A in FlG. 6 will first close contacts S8 and 97 to start operation of the drive motor in one direction with both the resistor strips 31 and 32 in the circuit, and further rotation of the hand grip in the direction of the arrow A will sequentially shunt out lirst the resistor strip 31 and then the resistor strip 32 to provide two additional speed steps. It the hand grip 77 is rotated in the opposite direction from that shown by the arrow A, the contacts 87 and 96 will be irst closed to operate the drive motor in the opposite direction, with both resistance strips 31 and 32 in the circuit, and further rotation of the hand grip in the same direction will sequentially shunt out first resistor strip 31 and then resistor strip 32 to provide two additional speed steps in the opposite direction.

If the hand grip 77 is released after rotation, the controller will be returned to the neutral position by the spring 82, whereby both sets of contacts S9, 96 and 88, 97 are opened, de-energizing the drive motor.

Referring now to FIGS. 7 and 8, there is shown a slightly different arrangement for moving the rods 69 and 70. In this arrangement, the rotatably mounted hand grip 77, shown in FIGS. l, 6 and 5, is replaced with a hand grip 98 which is ixed to the outer end of the handle 18 whereby the hand grip 98 cannot rotate. A sleeve 99 is rotatably mounted on a central portion of the hand grip 98, and the upper ends of the rods 69 and 70 are pivotally attached to the sleeve 99 on opposite sides of the axis of rotation of the sleeve, as best shown in FIG. 8. A pair ot rocker or wing plates lll and 101 ar-e secured to and extend from opposite sides of the sleeve 99. A curved guard plate 162 is secured at opposite ends to the outer end of the handle 18 and surrounds the rocker plates 100, 101 and the sleeve 99.

With this arrangement, when the operator wishes to d actuate the controller, he merely extends this thumbs within the guard plate 102 and presses down on either plate or 101 to thereby move the rods 69 and 7h in opposed directions to actuate the controller in the same manner as previously described in connection with the rotation of the rotatable hand grip 77.

From the preceding description, it can be seen that there is provided a novel controller which can be mounted in the handle of a walkie type industrial truck and which may be actuated through rotation of a control member on the handle to vary the speed of the truck and change the direction of movement of the truck.

While certain forms of the invention have been shown and described, it will be appreciated that changes and modifications may be made therein without departing from the spirit and scope of the invention.

I now claim:

1. A steering and control handle for an electrically motorized industrial truck of lthe type having a steering and traction unit, comprising a hollow body pivoted at its lower end to the said steering and traction unit, a control member rotatably mounted at `the upper end of said hollow body, resistors for the electric circuit of said truck mounted in said hollow body, electric contact means movable in said body to shunt the said resistors out of the electric circuit of said truck, a pair of directional switches within said hollow body, a pair ot longitudinal moving rods mounted in said hollow body, means connecting said rods with said control member so that said rods move in opposed directions when said control member is rotated in either of opposed directions, and means whereby the movement of said rods in opposed directions by said control member ac-tuates one or the other of said directional switches and also actuates said contact means to shunt out said resistors.

2. A steering and controller handle for an electrically motorized industrial truck of the type having a steering and traction unit, comprising a hollow handle pivoted at its lower end to the said steering and traction unit, a control member rotatably mounted at the outer end of said hollow handle, resistors for the electric circuit of said truclr mounted in said hollow handle, flexible electrical contact fingers mounted in said handle for shunting the said resistors out of the electric circuit ot said truck, a pair of directional switches witlnn said hollow handle, a pair or longitudinally moving rods mounted in said hollow handle, means connecting said rods to said control member on opposed sides of the axis of rotation of said control member whereby said rods are moved in opposed directions when said control member is rotated in either of said opposed directions, control means effective on rotation in a particular direction to flex said electric contact lingers to sequentially shunt said resistors out of the electric circuit of said truck, a lost motion connection between said control means and said pair of rods whereby said control means are rotated to sequentially shunt said resistors out of the electric circuit through movement of either of said rods in one direction through rotation of said control member', and means on each of said rods engageable with one of said pair or directional switches whereby movement of either of said rods in said one direction actuates one of said directional switches.

3. A steering and controller handle for an electrically motor-ized industrial truck of the type having a steering and traction unit, comprising a hollow handle pivoted at its lower end to the said steering and traction unit, a control member rotatably mounted at the outer end of said hollow handle, resistors for the electric circuit of said truck mounted in said hollow handle, tlexible electrical contact lingers movable in said body to shunt the said resistors out of the electric circuit of said truck, a pair of directional switches within said hollow handle, a pair of longitudinally moving rods mounted in said hollow handle, means connecting said rods to said control member eccentricallyl of the axis of rotation of said control member whereby said rods move in opposed directions when said control member is rotated in either of said opposed directions, control means effective on rotation in a particular direction to tlex said electric .contact ngers to sequentially shunt said resistors out of the electric circuit of said truck, a lost motion connection between said control means and said pair of' rods whereby said control means are rotated to sequentially shunt said resistors out of the electric circuit through movement of either of said rods in one direction through rotation of said control member, means on each of said rods engageable with one of said pair of directional switches whereby movement or either of said rods in said one direction actuates one of said directional switches, and heat ventilating passages in said hollow handle for dissipating heat from said resistors.

4. A steering and control handle for an electrically motorized industrial truck ot the type having a steering and tratcion unit, comprising a hollow handle pivoted at its lower end to the said steering and tratcion unit, a control member rotatably mounted at the outer end of said hollow handle, elongated U-shaped resistor strips for the electric circuit of said truck mounted in said handle and insulated therefrom, flexible contact iingers adapted to be flexed into electrical contact to connect opposite ends of said resistor strips together to thereby shunt said resistor strips out of the traction circuit of said truck, control means engage-able with one of said contact iingers to iieX said contact fingers into electrical contact to shunt out said resistor strips upon rotation thereof, a pair of longitudinally moving rods mounted in said hollow handle, means connecting the upper ends of said rods with said control member on opposite sides of the axis of rotation of said control .menber whereby said rods are moved Vin `opposed directions when said control member is rotated in either of opposed directions, a lost motion connection between the said rods and said control means whereby movement of either of said rods in one direction rotates said control means to shunt out said resistor strips, a pair of directional switches mounted in said hollow handle adjacent the lower ends of said rods with each ot said directional switches being engageable by the lower end of one ot said pair of rods, said rods in a neutral position of said control member holding said directional switch means open, and spring means for holding said control member in said neutral position while allowing said control member to be rotated in either of opposed directions to move one o said rods in said one direction to trst close one of said directional Witch means and then to rotate said .control means to sequentially shunt out said resistors.

5. A steering and control handle *for an electrically motorized industrial truck ofthe type having a steering and traction unit, comprising ahollowhandle pivoted at its lower yend to the said steering and traction unit, a controlmember rotatably mounted at the outer end of said hollow handle, elongated .U-shaped resistor strips for the electric .circuit of said truck mounted in said handle and insulated therefrom, llexible .Contact fingers adapted to be flexed into electrical contact to connect opposite ends ofsaid resistor strips together to thereby shunt said resistor strips out of the traction circuit of said truck, control means engageable with one of said contact lingers to flex said contact lingers into electrical contact to shunt out said resistor strips upon rotation thereof, a pair of longitudinally moving,1 rods mounted in said hollow handle, means connecting the upper ends of said rods with said control member on opposite sides o1" the axis of rotation of said control member whereby said rods are moved in opposed directions when said control member is rotated in either of opposed directions, a lost motion connection between the said rods and said control means whereby movement of either of said rods in one direction rotates said control means to shunt out said resistor strips, a pair of directional switches mounted in said hollow handle adjacent the lower ends of said rods with each of said directional switches being engageable by the lower end of one of said pair of rods, said rods in a neutral position of said control member holding said directional switch means open, and spring means for holding said control member in said neutral position while allowing said control member to be rotated in either of opposed directions to move vone of said rods in said one direction to first close one of said directional switch means and then to rotate said control means to sequentially shunt out said resistors, and heat Ventilating passages in said hollow handle for dissipating heat from said resistors.

Refer-ences Cited in the le of this patent UNITED STATES PATENTS 1,832,018 Gossard Nov. 17, 1931 2,401,113 Schroeder May 28, 1946 2,417,613 Radabaugh Mar. 18, 1947 2,588,664 Schreck Mar. 11 1952 2,942,679 Gibson June 28, 1960

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1832018 *Dec 12, 1928Nov 17, 1931Sarah L GossardSelf propelled scooter
US2401113 *May 15, 1942May 28, 1946Yale & Towne Mfg CoMotorized truck controller
US2417613 *Aug 22, 1944Mar 18, 1947Radabaugh John MElectric motor control and differential gear drive for lawn mowers
US2588664 *Sep 27, 1946Mar 11, 1952Schreck Irvin FDrive control for motorized hand lift trucks
US2942679 *Feb 6, 1957Jun 28, 1960Raymond CorpMaterial handling truck
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3405473 *Jan 11, 1965Oct 15, 1968Armand Boussageon Louis HenriFishing rods
US3465841 *Oct 11, 1967Sep 9, 1969Crown Controls CorpReversible electric motor speed control
US4444284 *Aug 5, 1981Apr 24, 1984Big Joe Manufacturing CompanyFor an industrial lift truck
US5064010 *Jun 21, 1989Nov 12, 1991Tennant CompanySpeed and steering control for scrubbers and the like
US7017689 *May 6, 2004Mar 28, 2006Crown Equipment CorporationElectrical steering assist for material handling vehicles
US7080703 *Aug 20, 2004Jul 25, 2006Jungheinrich AktiengesellschaftPedestrian truck
EP1470985A2 *Mar 4, 2004Oct 27, 2004Still S.A.R.L.Industrial truck
Classifications
U.S. Classification180/65.1, 180/19.2, 318/139, 180/19.3
International ClassificationB62D51/00, B60P1/02, B62B5/00, B62B3/04, B62B5/06, B62B3/06
Cooperative ClassificationB62B5/063, B60P1/027, B62D51/001, B62B3/0612
European ClassificationB62B3/06C, B62D51/00B, B60P1/02D