US1390992A - Elevating-truck - Google Patents

Description

D. E. HENNESSY.

ELEVATING TRUCK,

APPLICATION FILED JAN. II, I9l8.

Patented Sept. 20, 1921.

4 SHEETS-SHEET 1.

flea/e12 fol mud E Henhesfiy 2D I M 419 7014313.

D. E. HENNESSY.

ELEVATING TRUCK.-

Patented Sept. 20, 1921.

WM H s g F. e E M R N O R 8 m m EH. M V N NE 4 d WE APPLlCATlON FILED JAN. 11, 1918. 1,390,992.

D. E. HENNESSY.

ELEVATING TRUCK.

APPLICATION FILED JAN. 11 1919.

Patented Sept. 20,1921.

D. E. HENNESSY.

ELEVATING TRUCK.

I APPLlCATION FILED JAN. H, IBIS.

Patented Sept. 20, 1921.

4 SHEETS-*SHEET 4.

\ a fforne /s.

UNITED STATES PATENT OFFICE.

DANIEL E. HENNESSY, OF HOLYO KE, MASSACHUSETTS, ASSIGNOR TO HERBERT W.

OOWAN, J. LEWIS WYCKOFF, AND EDWARD N. WHITE, TRUSTEES, DOING BUSI- NESS AS THE GOWAN TRUCK COMPANY.

ELEVATING-TRUCK.

Specification of Letters ratent.

Patented Sept. 20, 1921.

To all whom it may concern:

Be it known that I, DANIEL E. HENNESSY, a citizen of the United States, residing at Holyoke, county of Hampden, and State of Massachusetts, have invented certain new and useful Improvements in Elevating- Trucks, of which the following is a clear, full, and exact description.

This invention relates to elevating trucks and particularly to elevating trucks of the type in which the elevation of the load is effected through mechanism operated from the steering and draft handle of the truck.

A general object of the invention is so to incorporate a jack, and particularly a mechanically operated step-by-step jack, in a truck of the aforementioned type, that the load lifting capacit of the truck may be many times increase without materially increasing the bulk of the truck, complicating its mechanism or interfering with its convenient handling in the restricted spaces a in which such trucks must frequently be used.

More particularly the invention aims so to incorporate multiplying levers in a truck, which has a load support arranged to be elevated by a combined lengthwise and upward movement of the support and a mechanically operated step-by-step jack extending lengthwise of the truck and arranged to be operated by the steering handle of the truck,-that said levers will transmit to the jack from thefhalndle, for each load lifting step, a much increased load lifting power.

An important feature of the invention, whicih contributes particularly to the compactness of the truck construction, is the provision, in combinatioii ;with a jack extending lengthwise of the truck, of one or more multiplying levers arranged upright at the forward end of the true whereby the power applied by the operator to the handle of the truck may be multiplied at the jack without materially increasing any dimension of the truck.

Another feature of the invention is the provision for automatic connection of the steering handle to the elevating mechanism when the steering handle is moved into position convenientl to operate the elevating mechanism. Stil other features and objects of the invention will appear from the following description and claims when considered in connection with the accompanying drawings, which illustrate the invention embodied in a truck of the type shown in my Patent No. 1,327 ,47 0, dated January 6, 1920.

In the drawings Figure 1 is a plan view of a truck embodying the present invention, parts of the truck being omitted in order to show other parts upon a larger scale;

g. 2 is a side elevation with parts in sfiectloln, of the portion of the truck shown in ig. 3 is a longitudinal section of the truck, showing details of the step-by-step jack mechanism and showing the arrangement of multiplying levers and the connection of these levers to the steering handle;

Fig. 4 is a rear elevation of the jack releasing means;

Fig. 5 is a bottom plan view of the mechanism shown in Fig. 4-; Fig. 6 is a rear elevation of the jack locking nut;

Fig 7 is a rear elevation of the jack operating nut;

Fig. 8 is a modification showing parts of the invention embodied in a truck of the hydraulic 'ack type, the truck being shown in longitu inal section;

Fig. 9 is a longitudinal section to one side of the section shown in Fig. 8 and illustrating more fully other parts of the truck which do not appear in the showing in Fig. 8, the full lines indicating the position of the parts when the platform is lowered, and the dotted lines indicating the elevated position of the platform;

Fig. 10 is a lan view of the modified truck shown in ig. 8;

Fig. 11 is an enlarged detail section on the line 1010 of Fig. 10; and

Fig. 12 is an enlarged transverse section on the line 4-4 of Fig. 10.

The illustrated truck is of the type having a single front steering wheel or a pair of steering wheels carried b a member arranged to swivel at the ront end of the truck, this member being connected to the steering handle, and the rear end of the truck being carried upon supporting wheels at the end of an axle extend ng across the truck, the truck being therefore a three 'wheeled truck with a single steering wheel and a pair of supporting Wheels.

In the illustrated preferred embodiment of the invention, the truck comprises a frame 2 having an upwardly and forwardly arched portion 4. At the forward end of the arched portion 4 of the frame is a vertical bearing in which the swivel pin 115 of a steering fork 113 is arranged to turn, this steering fork carrying a steering wheel 112 upon a axle pin 114. Atthe rear .of the frame, supporting wheels 111 are carried at the respective ends of an axle 109, extending across the frame 2.

The elevating platform 6 is arranged for a compound movement of elevation upon the frame, comprising a shifting movement and a lifting movement, the platform being maintained in parallelism to itself throughout this movement. This compound movement may be obtained in any suitable way, as, for example, by inclined members 123 and 124, such as shown in my patent hereinabove referred to.

The jack by which the shifting and lifting movements of the platform 6 are effected is pivotally mounted upon the truck frame 2 .so that it may swing about its pivots 8 as the platform is raised, and this jack comprises a jack post 10 having rigidly attached to its outer end a head 12 pivoted between ears 14 on a bracket 16 attached to the underside of the platform 6. The jack post 10 is provided with steep threads or grooves 18, the illustrated 'ack post having three of these threads. ounted upon the jack post are two nuts 20 and 22, the nut 20 being threaded to cooperate with all three of the threads 18 upon the jack post, and the nut 22 having two threads which cooperate with two of the three threads 18 of the jack post. The purpose of this differenoe in the threading of the two nuts will appear hereinafter.

It will be noted. that the threading of the jack post 10 is so steep that a movement of the jack post through the nuts 20 and 22, or a movement of the nuts 20 and 22 lengthwise of the jack post will cause the nuts to be turned upon the jack post. In order that advantage may be taken of this to effect a longitudinal movement of the jack post, provision is made for relative movements of approach and separation of the nuts and for alternately holding the nuts against turning.

' In the illustrated construction the nut 20 is mounted in a bearing member 24, which is carried upon the pivots 8 and is thus free to turn about said pivots during the operation of the jack but is held against movement lengthwise of the frame 2. The nut 20 is provided with a conical clutching surface 26, which cooperates with the correspondingly shaped inner face 28 in the rear end a corresponding cylindrical bore 31 in the bearing member 24, said neck portion being threaded at its forward end to receive a nut or collar 32 by which said nut 20 is confined in the bearing member, the collar 32 being so located upon the nut 20 that provision is made for movement of the nut 20 in the bore 31 whereby the clutching surface 26 upon the nut 20 may be moved into and out of engagement with the cooperating surface 28 upon the bearingmember 24. This movement of the nut 20 through the bore of the bearing 24 is sufliciently free so that it will be effected by the movement of the jack post. The nut ,22, like the nut 20, has a conical clutching surface 34 which cooperates with the correspondingly shaped inner surface 36 in a bearing member 38 for said nut 22. The nut 22, like the nut 20, also has a cylindrical neck portion 40 received in a cylindrical bore 41 in the bearing member 38 and threaded at its forward end to receive a collar 42 which confines said nut in its hearing. The bearing member 38 is provided with trunnions 44 which receive links 46 pivotally connected at 48 to a lever 50, of the second class, fulcrumed at 52 upon a bracket 54 at the forward end of the truck frame 2. Oscillation of said lever 50 about its fulcrum 52 effects, through the links 46, a reciprocation of the bearing member 38 upon the jack post 10. The nut 22, like the nut 20, is confined in its bearing member with provision for limited movement lengthwise of said member, whereby the surface 34 upon the said nut is moved into and out of clutching relation to the surface 36 on said member.

From the foregoing description it will be seen that when the bearing member 38 is moved toward the rear of the truck, that is,

toward the right in each of the figures in which it is shown, it will be brought into clutching relation to the nut 22 and will not only carry the nut with it but will also prevent it from turning upon the jack post 10, thereby causing the jack post also to be moved with said bearing member. Such movement of the jack post moves the nut 20 out of clutching relation to its bearing member 24, whereby the nut 20 is free to turn upon the jack post as the jack post is moved through it. When the bearing member 38 is again moved toward the front of the truck, that is, toward the left in each of the figures in which it is shown, it moves out of clutching relation to the nut 22, thus permitting this nut to turn freely upon the jack post. At the sametime the tendency of the jack post to move back to its original position causes the nut 20 to be moved into clutching relation to the bearing member 24, whereby this nut is prevented from turning and the jack post is thus held substantially in the position to which it has been moved by the movement of the bearing member 38 toward the rear of the truck. 'The jack post being held by the nut 20, the nut 22 is moved to a new position upon the jack post, and when the bearing member 38 is again moved toward the rear of the truck, the jack post is advanced still farther in its platform-lifting direction.

A lever 56, fulcrumed at 58 upon the arched portion 4 of the truck frame, has a pin 60 received in a slot 62 in the upper end of the lever 50 and is provided with a stop 64 arranged to engage a stop 66 upon the truck frame to limit the rearward movement of said lever. The lever 56 ma be connected in any suitable manner to t e handle by which the truck is drawn and steered, whereby it may be operated by a forward and backward movement of said handle to effect the oscillation of the lever 50, the connection to the draft handle of the truck being described more fully hereinafter.

It will be apparent that in order to release the jack to permit the load platform to be lowered, it is necessary that both the nut 20 and the nut 22 be permitted to turn freely upon the jack post 10. Means now to be described has been provided for effecting the release of the jack, such means being preferably arranged to be operated by the foot of the operator. The means operating to hold the nut 20 in released position will first be described:

The bearing member 24 for the nut 20 has a cylindrical extension 68 on the forward side of its pivotal axis, which is threaded to receive a cap 70, having a central bore through which the jack post 10 moves, and having a stud 72 projecting from its front face below said jack post. The stud 72 serves as a crank pin by which the cap 70 may be screwed back and forth upon the cylindrical art 68 of the bearing member. Between t e inner face of the cap 70 and the forward end of the nut 20 is a washer 74. When the parts are in the position shown in Fig. 3, it will be seen that the washer 74 fills the space between the end of thenut 20 and the inner face of the cap 70, the nut 20 being in its released condition, thus reventlation to its bearing member.

ing the nut from moving into clutc ing re- This is the released position of these parts and is not the normal position. In the normal position of these parts there is sufficient space between the inner face of the cap and the seat for the collar 32, so that the nut 20 may move freely into and out of clutching relation to the bearing member 24.

The means for moving the cap70 into the position shown in Fig. 3 comprises a bellcrank lever 76 having on one arm an upwardly extending forked portion 78 which embraces the stud 72, the other arm 80 of the bell-crank lever being bent upwardly out of the plane of the first mentioned arm, and having a universal joint connection 82 with a link or rod 84 connected at its other end to the lower arm of a treadle lever 86, fulcrumed at 88 upon the truck frame. A spring 90 confined between the collar 92 on the rod 84, and an upstanding portion 94 of the truck frame, tends to hold the treadle lever 86 in its elevated position and to hold the bell-crank 76 in such position that the cap 70 is maintained in the jack-operating position. In order that the nut 22 may also be held in such relation to its bearing member 38 that it will turn freely on the jack post as said post moves toward the platform-lowering position, an abutment 98 is provided against which the forward end of this nut strikes when the carrier 38 is moved to its extreme forward position, thus effecting a relative movement of the carrier and nut intounclutching relation.

In order that the operator may retard the lowering of the latform, braking means have been embodled in the jack-releasing means, the illustrated braking ,means comprising a conical friction surface 96 upon the collar 32, which coperates with a correspondingly shaped friction surface upon the inside of the bearing member 24. These two surfaces are preferably so shaped that they do not constitute a locking couple. It will be seen that as the operator presses his foot upon the treadle portion 87 of the treadle lever 86, he effects-the turning of the cap 70 to release the locking couple 20, 24, and further depression moves the friction surface 96 into contact with the friction surface on the member 24, thereby retarding the turning of the nut 20. The degree. of the retarding action depends obviously upon the pressure exerted upon the treadle 87.

In order to limit the lifting movement of the jack, a plug or stop 97 is located in that one of the threads 18 of the jack-post 10 which has no corresponding thread in the nut 22. The stop 97 will thus pass through the nut 22 and into engagement with the front end of .the thread in the nut 20 which travels in said groove or thread in which the stop is located. It will thus be seen that the jack can be extended by the operation of the nut 22 substantially to the end of the jack-post 10, and that the stop 97 will prevent over-extension or movement of the jack-post 10 out of operative relation to the nuts.

. As hereinabove suggested, an important feature of the invention is the arrangement, in combination with a mechanically operated step-by-step jack, of. a series of multiplying levers at the forward end of the truck .so arranged that the lifting power transmitted from the truck handle to the jack fo each lifting step of the jack will be many times multiplied, this arrangement being such that the bulk of the truck is not increased nor the convenience with which it may be manipulated in any Way diminished. It will be noted that the lever 50 through which the lever 56 transmits its movement to the jack-extending clutch, has its respective lever arms so proportioned that it constitutes a power multiplying lever in the chain of connections between the truck steering handle 118 and the jack, and that the lever 56 itself also has its arms so proportioned that it constitutes a power multiplying lever in this chain of connections. At the upper end of the lever 56 is a link 134, through which connection is made to the steering handle 118, this link having at its forward end an enlarged portion 135 provided with a recess shaped to hook over a pin 136 extending between the fork members 119 of the steering handle 118. This enlargement 135 is so located upon the link 134 that when the link 134 is not connected to the steering handle 118, the enlargement or head 135 rests upon the upper end of the swivel bearing 116. At its forward end the head 135 is so beveled, as shown, that when the handle 118 is swung into position to operate the jack, the pin 136 will engage the beveled face of the head 135 and cause the link 134 to ride up on the pin 136 until the recess in the head 135 comes into position over the pin 136, when the link will drop into connected relation to the handle 118.

It will be noted that the link 134 connects the lever 56 to the handle 118 at such a point, with respect to the fulcrum of the -whole chain of multiplying levers thus transmitting to the mechanically operated step-by-step jack many times the lifting power exerted-upon the handle by the operator, whereby the truck may be utilized to handle heavy loads.

In the modified form of the invention illustrated in Figs. 8 to 12 inclusive, a hydraulic jack of the type disclosed in my patent is shown, in combination with multiplying levers by which the power exerted u on the handle is multiplied many times tl frough the means by which it is transmitted to the jack. In this construction, however, it is not necessary to utilize so many multiplying levers to obtain the same multiplication of power, since a multiplica tion of power is obtained in the jack itself, such multiplication by the well-known laws of h draulics being in proportion to the relative areas of the pump piston and the jack piston or plunger.

In the modified form of the invention, the base 110 of the truck isprovided with rear wheels 111 and a front steering wheel 112, arranged substantially in the same manner as corresponding parts of the preferred form of the invention, the steering wheel being carried by a steering fork 113 swiveled in a bearing 116, in a bracket 117 at the forward end of the base 110. The steering handle 118 is provided with bifurcation 119 fulcrumed upon the ends of the axle pin 114. The platform 120 of the truck may be of any suitable construction, and its side bars 121 and the side bars 122 of the base may be formed of angle metal, as shown in Fig. 12.

The platform normally rests upon the base and may be raised orloWered through the intervention of suitable mechanism, the mechanism for this purpose, herein illustrated, comprising inclined members 123 upon the base, presenting their inclined surfaces upwardl and inclined members 124 upon the plat orm 120, presenting their inclined surfaces downwardly, the two inclined surfaces engaging for relative sliding movement. The particular means for effecting the elevation of the platform constitutes no part of the present invention, and consequently may be replaced by other well known means for effecting a combined longitudinal and vertical relative movement of the platform and base. The jack 126 and the associated pump 125 are preferably rigidly connected, the pump being rovided with lateral bearing sockets 128 w ich receive suitable pivot pins 129 rigidly mounted on the front portion of the base, as shown in Fig. 8. The piston rod 130, connected to a suitable piston within the pump 125' is connected by a link 131 to a-lever 132 which is fulcrumed upon the extension 117 of the base, the upper arm of this lever being longer than the lower arm and being pivotally connected at its end to the link 134, which is provided with a recessed head 135 adapted'to be engaged with the pin 136 on the truck handle 118 in the manner hereinabove described. in connection with the preferred form of the invention. When the handle is free from said link, the truck may be steered thereby, but when it is engaged therewith, the piston 130 of the pump may be reciprocated by the oscillation of said handle, which serves as a hand-lever.

The ram 140 of the hydraulic jack is pivotally connected at 145 with the rear end of the platform 120, and the jack is so constructed with suitable valves, more fully described in my co-pending application Serial No. 194,591 hereinabove identified, that a step-by-step extension of the jack may be effectedand a corresponding step-by ste-p elevation of the platform. The hydraulic 166 on the truck base.

between its respective pivotal connections to the base and to the platform, as the platform is elevated upon the base.

The modified form of the invention, like the preferred form, preferably includes manually controlled means for releasing the jack to permit the platform to move to its depressed position, the illustrated means including a valve, more. fully shown and described in the co-pending application Serial No. 194,591 hereinabove identified, this valve being controlled by a plunger 162 projecting to theoutside of the jackcasing and arranged in the path of an arm 167 on a rock shaft 165 journaled in suitable bearings An arm 171 on the rock shaft 165 is connected by a link 172 with a pedal 173 pivoted upon the base at.

174. A spring 175 tends normally to keep the pedal 173 in raised position and thereby to hold the arm 167 out of engagement with the plunger 162.

In order to prevent over-extension of the jack and elevation of the platform beyond a predetermined limit, a link 169 is connected to another arm 168 on the rock shaft 165, and has a lost motion connection with the underside of the platform, comprising a nut 170 adjustably threaded upon the rod, this nut being adapted to engage the end of the guide 180 when the platform reaches its uppermost position, whereby further movement of the platform will cause the rock shaft 165 to be rocked, thus bringing the arm 167 into engagement with the plunger 162 to prevent further extension of the jack.

What I claim as new is:-

1. In an elevating truck, the combination with a base having supporting and steering wheels and an elevating support movable up and down upon said base, of meansfor effecting the up and down movement, comprising a step-by-step jack arranged and operating lengthwise of said base and a series of multiplying levers having their long arms projecting upward and swinging in front of said elevating support at the forward end of said truck and having their fulcra vertically spaced, said series of levers having a positive connection with said jack through which the oscillations of said levers are transmitted to said jack to effect the step-by-step movement thereof.

2. In an elevating truck, the combination with a base, supporting wheels and a steering swivel, and an elevating support movable up and down upon said base, of means for effecting the up and down movement, comprising a mechanically operated step-bystep jack arranged and operating lengthwise of said base beneath said support, a steering and draft handle mounted upon said swivel and means for operating said jack from said steerin and draft handle, comprising a series o multiplying levers arranged with their fulcra in substantially vertical alinement between said elevating support and said steering swivel.

3. In an elevating truck, the combination with the truck base, supporting and steering wheels for said base and an elevating sup port movable up and down upon said base, of means for effecting the up and movement of said support, comprising a step-by-step jack extendin lengthwise of said base, a steering hand e connected to the steering wheel to swing therewith and arranged to swing also in a vertical plane, and a multiplying lever for connecting said steering handle to said jack to effect the step-by-step movement of said jack by the vertical swinging movement of said handle, said lever projecting upward in front of said elevating support and being connected to said handle above said steering wheel.

4. An elevating truck having, in combination, a truck base, a steering wheel havin a swivel connection with the front end 0 said base, a steering handle pivoted upon the steering swivel, load lifting means, comprising a load support and a step-by-step jack operating lengthwise of said base and beneath said load support, and operatingv connections between said steering handle and said jack, including a multiplying lever extending upwardly between said load support and said swlvel and a link connecting the long arm of said lever with said handle above said swivel.

5. In an elevating truck, the combination with the wheeled truck base having a steering swivel at the front of said base, a steering handle connected to the steering swivel to swing therewith and vertically thereon, and an elevating support, of means for effecting the up and down movement of said elevating support upon said base, comprising a step-b -step jack operating lengthwise of said truck a multiplying lever at the forward end of said truck having a depending short arm connected to said ack and having a long arm projected at all times into the space between said elevating support and said steering swivel, and a power multiplyin connection between said long arm and said steering handle for operating said lever and said jack from said steering handle.

6. In an elevating truck, the combination with the wheeled truck base having a steering swivel at the front of said base, a steering handle connected to said swivel to swing therewith in steering and to swing vertically thereon, and an elevating support mounted upon said base for combined lengthwise and up and down movement thereon, of means for effecting the movement of said support upon said base, comprising a mechanicallyoperated' step-by-step jack extending lengt wise of said truck, a multiplying lever mounted upon said base between said jack and said swivel and having a depending short arm connected to said jack, and a long arm located at all times in the space between said elevating support and said swivel and arranged to be connected to said steering handle to be operated by the vertical swinging movement thereof.

7. In an elevating truck, the combination with a wheeled base, load lifting means comprising a load support and a step-by-step 10 ack operating lengthwise of said base beneath said load support, and jack releasin means having a lost motion connection wit said load support.

Signed at Holyoke, Massachusetts, this 15 15th day of December, 1917.

DANIEL E. HENNESSY.

Images