US1773934A

US1773934A - Lift truck

Info

Publication number: US1773934A
Application number: US81191A
Authority: US
Inventors: Arthur M Barrett
Original assignee: BARRETT CRAVENS CO
Current assignee: BARRETT CRAVENS CO
Priority date: 1926-01-14
Filing date: 1926-01-14
Publication date: 1930-08-26
Anticipated expiration: 1947-08-26

Description

Aug. 26, 1930.

A. M. BARRETT LIFT TRUCK 5 Sheets-Sheet 1 Filed Jan. l4, 1926 Aug. 26, 1930. A. M. BARRETT 1,773,934

' LIFT TRUCK Filed Jan. 14, 1926 3 Sheets-Sheet 2 P. A w b W a J n 6 5 A o I q i 2 .v V l 9 M M). J v e v 6 6 n m 9 l w I Au 26, 1930. A. M. BARRET T 1,773,934

LIFT TRUCK Filed Jan. 14, 1926 s Sheets-Sheet s type designed to'be Patented Aug. 26, 1930 UNITED STATES PATENT orFicE ARTHUR M. BARRETT, OF WINNETKA, ILLINOIS, ASSIGNOR TO BARRETT-CRAVEN? COMPANY, OF CHICAGO, ILLINOIS,

A CORPORATION OF ILLINOIS LIFT TRUCK Application filed January 14, 1926. Serial No. 81,191.

invention relates to lift trucks of the backed under a low platform on which the load is placed for lifting the platform and its load totransport the load from place to place, and has for its objects to provide a lift truck of improved construction so designed that the load may be lifted by a step by step movement effected by repeated strokes of the usual steering lever or handle, and in which the load will be held up by hydraulic means which, as a further feature of improvement,'serves also to cushion the descent of the load so that it descends gradually; also to provide lifting means by which the pull on the lifting lever required to lift the load is substantially the same at all stages of the lifting operation. I accomplish these objects as illustrated in the drawings and hereinafter described. What I claim as new is set forth in the claims.

In the accompanying drawings,

Fig. 1 is a side elevation, with some parts broken away, of my improved truck showing the lifting frame or platform in its lowered or load receivingposition;

Fig. 2 is principally a plan view of the truck, some parts beingbroken away and some other parts being shown in horizontal section;

Fig. 3 is a central longitudinal vertical section of'the front part of the truck showing the parts in loading position;

Fig. 4: is a similar view showing the lifting frame partly elevatedto load transporting position;

Fig. 5 is a partial longitudinal vertical section on line 5-5 of Fig. 2, illustrating some of the operating parts, including the hydraulic check by which the load is held up, in the position they occupy when the lifting frame is in its lowered position;

Fig. 6 is a similar view showlng the posi as it rises or descends, 8, 9 indicate the side members of the main frame, which are in the form of metal bars of any suitable commer-' cial shape connected together near their rear ends by a transverse bar 10, referabl of angle iron, as shown in Fig. 2. aid side ars are also connected by a rear axle 11 which carries rear wheels 12. The axle 11 is preferably located at the extreme rear ends of the side bars 8, 9, and the cross-bar 10 is placed a short distance forward of the rear wheels, as shown in Fig. 1. The front ends of the side members 8, 9 of the main frame are connected by a cross-head 13 secured thereto by

bolts

14, 50, and having a central opening to receive a vertical spindle 15 and provide a bearing therefor. The spindle 15 rises froma yoke 16 derstood that my improvements may be applied to a truck having a single steering wheel, and the steering wheel or wheels may be connected with the truck in any approved way, as my present invention is not concerned with the specific manner in which the steering wheel or wheels are mounted. In the construction shown the steering wheel spindle 15 is provided at its upper end with a head 19 secured to said spindle so as to rotate therewith and having forwardly extending ears 20, as best shown in Figs. 2 and 3.

Pivotally connected with said ears is a steering handle or lever 21, the lower end portion of which is bifurcated to provide separate members 22 that fit against the outer surfaces of the ears 20 and are connected thereto by a transverse pivot 23. By this arrangement the steering handle may swing about the ivot 23 to assume either a substantially upright position or an approximately horizontal position. i It may also be used to "rotate the head 19' to steer the front wheels.

Also mounted on the pivot 23 is a shackle arm 24 which is adapted to extend up alon sidethe' rear side of the handle 21 and to e connected thereto by a latch 25 to swing in unison therewith, and to be rocked thereby I handle 21 for raising the lifting frame com-.

about the pivot 23. The shackle arm 24 is preferably mounted between the ears 20, as shown in Fig. 2, and is provided with a stop 26 which prevents it from swinging back beyond a substantially 11 right position. A cross bar 27 on the han e 21 limits its rearward movement by engaging the shackle arm, as shown in Fig. 3. By tripping the latch the shackle arm 24 may be disconnected from the handle so that the latter may be swung u or down independently thereof. Said shack e arm serves to connect the handle 21 with. the lifting mechanism by which the lifting frame is raised, as will be hereinafter described. The lifting frame comprises side members 28, 29 which extend longitudinally over the side members 8, 9 of the main frame and are connected at the rear by a cross-bar 30, as shown in Fig. 2, said bar being preferabl of angle iron as shown by dotted lines in ig. 1. Near their forward ends the side members 28, 29 are connected by a cross-bar 31 preferably of angle iron, having one of its flanges turned up as shown at 32 in Fig. 1. The horizonta flange of said bar 31 has its end portions turned-down and secured to the side members 28, 29 by rivets 33. Thus the

crossbars

30, 31 together securely tie the sidemembers 28, 29 together and form a strong frame or platform to carry the load.

The lifting frame is supported on the axle 11 by

links

34, 35 securely connected at their lower ends with the axle and extending upwardl and rearwardly to a point under t crossar where the are pivotally connected with the lifting rame in any suitable way, as'b a transverse shaft 36. A desirable construction for this purpose is fully-shown and described in Letters PatentNo. 1,551,630,

granted to me September 1, 1925. The for ward ends of the side members 28, 29 are connected with the ivots 14 of the main frame by swinging linl s' 37, 38 which are ap roximatel parallel with the

links

34, 35. hen the li ting frame is in its lowered position the links 37,38 extend upward and rearward to the forward ends of the side members 28, 29 of the lifting frame, with which they are connected

b pivots

39, 40. It will be evident therefore, t at if the lifting frame be'move forward relatively to the main frame it will also rise, being carried up by the two pairs of swinging

links

34, and 37, 38, respectively.

The mechanism actuated by the steering prises two swinging

links

41, 42, preferably triangular in shape, which are pivotally connected with the side members 28, 29 of the lifting frame, preferably by means of a transverse shaft 43 best shown in Figs. 3 and 4. Said links are arranged to swing fore and aft and are located a short distance from the adjacent side members 28 29. Between the lower end portions of said links and the adjacent side members of the truck are

toggle links

44, 45 pivotally connected with the

links

41, 42, respectively, by pivots 46, and connect ed by pivots 47 with

links

48, 49, the forward ends of which are connected with the forward end portions of the side-members 8, 9 by the bolts 50. On the upper margins 51 of the

links

48, 49 travel rollers 52, 53 pivotally carried at the forward end portions of the side members 28, 29 of the lifting frame in position to overlie said links. The surfaces 51 on which said rollers run are cam cut, as shown in Fig. 4, for reasonshereinafter given.

It will be seen from the foregoing that each pair of links 44 48 and 45, 49 constitute a toggle, and that lfy swinging the

links

41 and 42 forward from their normal position,- that is to say the position they occupy when the lifting frame is in its lowered position,-- the

links

48, 49 will be swung upward to the position shown in Fig. 4, thereby pressing upward and forward on the rollers 52, 53, and consequently causing the lifting frame to move forward and upward through the swinging of the

rear links

34, 35 and the front links 37, 38 that connect the lifting frame with the main frame. As the lifting frame rises the rollers 52, 53 will travel rearwardly and upwardly on the

links

48, 49, as clearly shown in Fig. 4.

The lower ends of the

links

41, 42 are swung forward to raise the lifting frame in the manner above described, by means of a power transmitting device in 'the form of a ratchet bar 54 which extends rearwardl and downwardly from the shackle mem er 24, with which it is connected by means of an eye 55 formed at the forward end of said ratchet bar "and slipped over said shackle member, as

is loosely or swingingly connected with said shackle member so that it does not interfere with lateral swinging of the steering handle. Toward its rear end the ratchet bar 54 is provided at its up er surface with ratchet teeth 56 which are a apted to intermesh with teeth 57 formed on the under side of a cross-bar 58, the ends of which are mounted in the

links

41, 42, as shown by dotted lines in Fig. 2, sothat said cross-bar swings with said links about the shaft 43 as an axis. The purpose of giving the surfaces 51 of the links 48, 49 a cam conformation is to cause a substantially uniform upward and forward movement of the ratchet bar 54 and cross bar 58 for each unit of vertical movement of the lifting frame, so that the pull on the lifting handle required is substantially the same at all stages of lift; and also to obtain a substantially straight line motion of the cross-bar 58 and ratchet bar 54. The lower rear end portion of the ratchet bar 54 may swing toward or from the crossbar 58 to engage or disenga e the teeth 57, and the free end of said ratc et bar overlies a roller 59 mounted in the lower arms 60 of two bell crank levers 61 which are spaced apart a distance somewhat greater than the width of the ratchet bar 54, and are fulcrumed on a pivot 62 mounted between the forwardly extending

arms

63, 64 of a yoke 65, best shown in Fig. 7. The cross-bar 58 extends through the

arms

63, 64 of said yoke, adj acent' to their front ends, which extend downward in advance of said cross bar, as clearly shown in Figs. 5 and 6, the pivot 62 beingmounted in said arms a little below and in front of the cross-bar 58. The levers 61 are provided with upwardly extending arms 66 which project up in front of the cross-bar 58 for a purpose which will be hereinafter explained. At present it will suffice to say that the arrangement is such that by pressing down on the ratchet bar 54, through its engagement with the roller 59 it will rock the levers 61 about the pivot 62 in a counter-clockwise direction, thereby moving the upper arms 66 of said levers toward the cross-bar 58.

Formoving the ratchet bar 54 toward or from the cross-bar 58 I provide a pedal 67 fulcrumed on a pivot 68 mounted in ears 69 carried by the cross-head 13, as best shown in Fig. 2. Said pedal comprises a forwardly extending foot lever 7 O and an upwardly extending foot lever 71, as best shown in Fig. 3. It also comprises a rearwardly extending arm 72 which projects at one side of the ratchet bar 54 and carries two transversely disposed

rods

73, 74 spaced apart and projecting across the ratchet bar 54, respectively above and'below the same. Said rods are spaced far enough apart so that the ratchet bar may move freely lengthwise of itself between them, but by rocking the pedal in one direction or the other it will be apparent that the lower end of said ratchet bar may be moved toward or from the cross-bar 58. Actuation of the foot lever 70 lifts the lower end of said ratchet bar into engagement with the teeth 57 through the agency of a leaf spring 75, so that it is yieldingly held in engagement therewith, whereas actuation of the upright lever 71 disengages said ratchet bar from said teeth. Normally the ratchet bar drops away from said teeth by gravity and assumes the P05151011 illustrated in full lines in Figs. 3 and 4. The, ratchet teeth 56 are so inclined that when said ratchet bar engages the teeth 57 under theaction of the spring it may be moved downward and rearward past said teeth and independently of the cross-bar 58, but on upward and forwardmovement of sald ratchet bar one of its teeth will enga e the teeth 57 and consequently swing the lin s 41, 42 forward and actuate the toggle links 44, 48 and 45, 49 described.

The operation of the lifting devices as thus fardescribed is as follows: Assuming that the lifting frame or platform is in its low- 79 in said flange.

in the manner that has been I ered position, the parts will then occupy the relation to each other shown in Fig. 3 except that the lifting handle may or may not be in its upright position. Of course, when the truck is being hauled from place to place the lifting handle is disconnected from the shackle member 24 and is turned down to a convenient position for hauling and steering the truck. When the operator desires to. lift the load he swings the handle up to the position shown in Fig. 3 and the latch 25 automatically engages the shackle member 24, thereby locking it to the handle. He then depresses the foot lever 7 O to rock the pedal in a clockwise direction, thereby swinging the arm 72 upward and, through the transverse rod 74 and spring 75, lifting the ratchet bar 54 into engagement with the teeth 57.

By then rocking the steering handle back? and forth, with long or short strokes as he may prefer, he lifts the load by a step by step movement. Forward movement of the lifting handle swings the

links

41, 42 forward, thereby moving the

toggle members

44, 45 and 48, 49 to a more acute angular relation to each other, as shown in Fig. 4, the rear/ ends of the

members

48, 49 IIlOVlIlg upwardly and consequently swinging the li forward and upward, as shown in said figure. Upon backward movement of the steering handle the ratchet bar 54 trips over the teeth 57 without affecting the position of the

links

41, 42.

During the lifting operation the load issustained by means of a fluid check apparatus, which also serves to cushion its descent, as will now be explained. Referring particularly to Figs. 5 to 7, 76 indicates a hydraulic cylinder, preferably composed of two members 76*, 7 6", the member 76 being of smaller diameter than the member ,76", and

ing frame being fixedly connected telescopically therewith. Said cylinder extends longitudinally of the truck, preferably centrally tliereofas shown ,in Fig. 2, and at its rear end is provided with'a head 77 connected with the vertical flange of the cross-bar 10 by a bolt 78 which passes loosely through an opening A spring 80 interposed between the'head 81 of said bolt and said flange holds the head 77 yieldingly against it. The forward end of the cylinder member 76 is provided with'a head 82 havinga gland 83 and packing 84. Through the gland 83 extends a tubular shaft 85, the rear end of which communicates with the interior of the cylinder through a passage 85, and carries a piston 86 which operates in the cylinder mem er 76 and is moved longitudinally therein incidentally to movement of the lifting frame, but performs no lifting function.

Said piston is provided at its rear end with a valve chamber 87 having an annular seat 88 for a ball valve 89, which is confined in the chamber 87 by a cage '90. The valve 89 :the check valve 89.

The forward end of the shaft 85 is fixedly connected with the central portion 92 of the yoke 65. The arms 63, 64: of said yoke are provided with sleeves 93, 94 which fit on the cross-bar 58 and are non-rotatably secured thereto, as by pins 95, as best shown in Fig. 7. By this construction, when the

links

41, 42 move forward and upward, as the lifting frame rises the shaft 85 is drawn forward, permitting the liquid in the cylinder 76 to pass to the rear of the ascribed. Consequently the check valve 89, by preventing reverse flow of the liquid, will normally hold the lifting frame in any position to which it may be lifted.

To permit the descent of the lifting frame a rod 96 is provided;which extends through the tubular shaft 85 and at its rear end is reduced in diameter, or provided with a pin 97 which is adapted to project through the port 91' into engagement with the ball valve 89, so that by rearward movement of said rod the valve may be moved away from its seat, thereby opening the port 91 and permitting the liquid to flow through the piston into the fore part of the cylinder 76. The rod 96 extends forward of the front end of the shaft 85 and a gland 98 is provided to prevent leakage at that point. The forward end of said rod is connected to a cross head 99 lying between the

arms

63, 64 of the yoke 65 adjacent to the cross-bar 58 as shown in Fig. 7, between the ends of which cross head and-the arms 66 of the levers 60 are interposed pins 100 arranged to slide in hearings in the cross-bar 58, as shown in said figure. The forward ends of said pins are preferably connected to the*arms 66 by cotter pins 101. A spring 102 is preferably mounted on the tubular shaft 85 between the piston 86 and thehead 82, as shown in Figs. 5 and 6, to aid in starting the descending movement of the lifting frame. The rod 96 is actuated to move the valv 89 away from its seat and permit the lifting frame to descend, in the following manner: When the operator wishes to lower the lift mg frame he depresses the lever 71 thereby rocking the pedal in a counterclockwise" direction as viewed in Fig. 4, and through the transverse rod 7 3 positively moving the lower end of the ratchet bar 54 downward be? gond the position it assumesfby gravity. uch movement of the ratchet bar acts through the roller 59 to rock the levers 60 in piston 86 as above the cross head 99 back, thereby moving the A red 96 rearwardly and consequently unseating the valve 89. To prevent accidental un- I seating of said valve, and to return the parts to normal position, a spring 103 is provided between the gland 98 and the cross head 99, as shown in Figs. 5 and 6. 7 Upon the unseating of said valve the fluid in the rearward portion of the cylinder member 76 is permitted to flow through the piston 86 andpassage 85* to the cylinder 76, so that said piston can move rearwardly and permit the descentof the load. When pressure on the foot lever 71 is released the spring 103 moves the cross head 99 forward and rocks the levers 60 in a clockwise direction back to their normal position, while at the same time the rod 96 is moved forward to permit the valve 89 to seat. thereby preventing further descent of the load.

From the foregoing description it will be seenthat by my improved construction the load is automatically sustained at any point i to which it may be lifted, and that it may be arrested at any point in its descent. B

connecting the forward end of thecheck cy inder with the lifting frame through the links 41, 42 I obtain a practically uniform extension of the shaft 85 as the lifting frame rises, since the piston 86 moves a practically uniform distance for each vertical unit of movement of the lifting frame. It follows, of course, that a uniform checking of the descent of the load is also obtained. By means of the liftin mechanism described the pull required in lifting the load is substantially the same at all stages of the lifting o eration,

so that the truck operates easily un er heavy load. In practice in lifting a light load the lifting handle 21 would be given longer strokes than for lifting a heavy load, but the len 'th of the stroke 1s, of course, optional with the operator. Ordinarily in lifting a light load two strokes of the handle would be suflicient, while a maximum load can readily be lifted by five short strokes.

So. far as I am aware, I am the first in the art to rovide a lifting truck of the type described in which the liftin is accomplished by mechanical means and t e holding up of the load is effected by hydraulic means, and, as a further improvement, to employ such hydraulic means as a check to control the descent of the load. These features, therefore, are claimed generically. Furthermore, I wish it to he understood that the claims hereinafter made are not intended to be restricted to the specific construction shown and described, except in so far as they are directed to details of such construction, as various modifications will be apparent to those skilled in the art. 1

links operable by said lever, and toggle mechanism actuated by said links and having cam surfaces for applying lifting force to the lifting frame.

2. A lift truck comprising a main frame,

0 an endwise movable lifting frame, a lifting lever, toggle mechanism for moving the lifting frame endwise in one direction to lift the same, means operatively connected withsaid lifting lever for actuating said toggle mechanism to lift the lifting frame step by step, and hydraulic means for normally holding the lifting frame against endwise movement in the opposite direction.

3. A lift truck comprising a main frame, a lifting frame, a lifting lever, toggle mechanism for lifting the lifting'frame, ratchet devices movable longitudinally of the main frame, and operatively connected with said lifting lever for actuating said toggle mechanism to lift the lifting frame step by step, and means for normally holding the lifting frame against descent. I

4.. A lift truck comprising a main frame, an endwise movable lifting frame, a lifting lever, swinging links connected with one of said frames, toggle mechanism connected with said links and operable by movement thereof to move the lifting frame endwise in one direction to lift the same, means operatively connected with the lifting lever and operable thereby to actuate said links to lift the lifting frame, and hydraulic means connected with said links for normally holding said lifting frame against descent.

5. A lift truck comprising a main frame, a lifting frame, links pivotally connected with the lifting frame to swing fore and aft, toggle mechanism connected with said links and with the main frame and operable by the swinging of said links to lift the lifting frame, a lifting lever mounted on the main frame, and ratchet devices carried by said links and actuated by said lever for swinging said links.

6. A lift truck comprising a main fi ame, a lifting frame, links pivotall connected with the lifting frame to swing ore and aft, toggle mechanism connected with said links and with the main frame and operableby the swinging of said links to lift the lifting frame, a lifting lever mounted on the main frame, ratchet devices carried by said links and actuated by said lever for swinging said links, and hydraulic means for normally holding the lifting frame against descent.

7 A lift truckcomprisin a main frame, a lifting frame, links pivotal y connected with the lifting frame to swing fore and aft, toggle mechanism connected with said links and with the main frame and operable by the swinging of said links to lift the lifting frame, a lifting lever mounted on the main frame, a ratchet tooth connected with said links, a ratchet bar connected with said lever andmovable into or out of operative engagement with said ratchet tooth, and means for normally holding the lifting frame against descent.

8. A lift truck comprising a main frame, a lifting frame, links pivotally connected with the lifting frame. to swing fore and aft, toggle mechanism connected with said links and with the main frame and operable by the swinging of said links to lift the lifting frame, a lifting lever mounted on the main frame, a ratchet tooth connected with said links, a ratchet bar connected with said lever and movable into or out of operative engagement with said ratchet tooth, and hydraulic means for normally holding the lifting frame against descent.

9, A lift truck comprising a main frame, a hftmg frame, links pivotally connected with the lifting frame to swing fore and aft, toggle mechanism connected with said links and .with the main frame and operable by the swinging of said links. to lift the lifting frame, a lifting lever mounted on the main frame, a ratchet tooth connected with said links, a ratchet bar connected with said lever and movable into or out of operative engagement with said ratchet tooth, hydraulic means for normally holding the lifting frame against descent, and means operated by movement of said ratchet bar out of engagement with said ratchet tooth for actuating said hydraulic means to permit the descent of the lifting frame.

10. A lift truck comprising a main frame, a lifting frame, links pivotally connected with the liftingframe to swing fore and aft, toggle mechanism connected with said links and with the main frame and o erable by the swinging of said links to 1i t the lifting frame, a lifting lever mounted on the main frame, a ratchet tooth connected with said links, a ratchet bar connected with said lever and movable into or out of operative engagement with said ratchet tooth, hydraulic means for normally holding the lifting frame against descent, means operated by movement of said ratchet bar out of engagement with said ratchet tooth for actuating said hydrauhe means to permit the descent of the lifting frame, and means operable to move said ratchet bar into or out of engagement with said ratchet tooth.

11. A lift truck comprising a main frame,

ment with said ratchet tooth, hydraulic means for normally holding the lifting frame against descent, means operated by movement of said ratchet bar out of engagement with said ratchet tooth for actuating said hydraulic means topermit the descent of the lifting frame, means operable to move said ratchet bar into or out of engagement with said ratchet tooth, and a spring for normally movin the ratchet bar into engagement with said ratchet tooth.

' 12. A lift truck com rising a main frame, a lifting frame, a lifting lever, mechanical lifting devices operable step by step by said lever to lift the lifting frame, a fluid check comprising a piston. actuated incidentally tomovement of the lifting frame, and normally operating to hold the lifting frame at all stages of its lifting movement against descent, and lever mechanism operable to release said fluid check to permit the lifting frame to descend.

13. A lift truck comprising a main frame, a liftin frame, a lifting lever, mechanical lifting devices operable step by step by said lever to lift the liftin frame, a cylinder connected with one of said frames, a piston connected with the other frame and movable in said cylinder incidentally to the raising or lowering of the liftin frame, a check valve controlling the flow of fluid past said piston in one direction and operating normall to hold the lifting frame at all stages of its ifting movement against descent, and means operable to move said check valve out of operative position to permit descent of the lifting frame.

14. A lift truck comprising a main frame, a lifting frame, a lifting lever, lifting devices operable step by step by said lever to lift the lifting frame, a cylinder connected with the main frame, a piston movable in said cylinder incidentally to the raising or lowering of the lifting frame, said iston having a passage therethrough, a check valve normally closingsaid passage to prevent descent of the lifting frame, and means operable to move said check valve out of operative position.

15. A lift truck comprising a main frame, a lifting frame, a liftin lever, mechanism operable by said lever to 11ft the lifting frame step by step, a cylinder connectedwith the main frame, a piston movable in said cylinder and connected with said lifting frame, said piston being actuated to move longitudinally in said cylinder incidentally to the lifting or lowering of the lifting frame, a check valve normally preventing flow of liquid in said cylinder around said piston to hold the lifting frame against descent, and means op-' erable to move said check valve out of operative position.

16. A lift truck comprising a main frame,

a lifting frame, a lifting lever, lifting devices for lifting the lifting frame, a ratchet device connected with said lifting devices, a ratchet bar connected with said lifting lever and movable into and out of engagement with said ratchet device, a cylinder connected with the main frame, a piston operating in said cylinder and connectedwith the lifting frame, a check Valve normally preventing flow of liquid in said cylinder around said piston to hold the liftin frame against descent, and devices actuated y movement of said ratchet bar out of enga ement with said ratchet device to move sai check valve out of operative position.

' 17. A lift truck comprising a main frame, a lifting frame,a lifting lever, swinging links connected with the lifting frame, llfting devices connected with said links and operable by the swinging thereof to lift the lifting frame, a ratchet tooth connected with said swinging links, a ratchet bar connected with the lifting lever and movable into or out of engagement with said ratchet tooth, a cylin-' der connected with the main frame, a piston movable i said cylinder and connected with the lifting frame, a check valve normall preventing t yv of liquid past said cylin er, to hold the liftin frame against descent, and devices actuated by movement of said ratchet bar away from said ratchet tooth to move said check valve out of operative position.

18. A lift truck comprising a main frame, a lifting frame, a lifting lever, swinging links connected with the lifting frame, lifting devices connected with said links and operable by the swinging thereof to lift the liftin frame, a ratchet tooth connected with sai swinging lin s, a ratchet bar connected with the lifting leyer and movable into or out of. engagement with said ratchet tooth, a cylinder connected with the main frame, a lston movable in said cylinderand connecte with the lifting frame a check valve normally preventing flow of liquid past said cylinder, to hold the lifting frame against descent, a rocking lever actuated b movement of said ratchet bar away from said ratchet tooth, and

means actuated b said rocking lever for moving said check val ve out of operative position.

19. A lift truck comprising a main frame, a lifting frame, a lifting lever, swinging links connected with the lifting frame, a ratchet bar operable by said lifting lever and movable into and out of operative engagement with said links toggle mechanism conment with said links, toggle mechanism con nected with-said links and comprising links having cam surfaces, rollers carried by said lifting frame and running on said cam surfaces, a cylinder connected with the main frame, a piston operating in said cylinder and connected with said first mentioned links, a check valve normally preventing flow of liquid in said cylinder around said piston, to hold the lifting frame. against descent, and means for moving said check valve out of operative position to permit descent of the lifting'frame.

21. In a lift truck, a main frame, a lifting frame, mechanical means having positive mechanism connection to the lifting frame for raising said lifting frame, and hydraulic means normally acting to hold the lifting frame against downward movement, the lifting frame being otherwise free for downward movement when raised, said hydraulic means being operable to release the lifting frame and cushion lowering thereof. a

22. In a lift truck, a main frame, a lifting frame, a lifting lever,mechanical means comprisin ratchet devices operable by said lever 'or raising the lifting frame, and hydraulic means disposed longitudinally of the truck and normally acting to hold the lifting frame against downward movement, said hydraulic means being operable to release thev lifting frame and cushion lowering thereof.

23. In a lift truck, a main frame, a lifting frame, a lifting lever, mechanical means comprisingratchet devices operable by said lever for raising the lifting frame step by step, and hydraulic means disposedlongitudinally of the, truck and normally acting to holdthe lifting frame against downward movement, said hydraulic means being operable to release the lifting frame and cushion lowering thereof.

24. In a lift truck, a main frame, a lifting frame, a ratchet member, means connected to said member and actuated thereby for raising the lifting frame, a lever mounted on the main frame, and a ratchet bar connected to the lever arid movable into operating relation to the ratchet member, said bar being subjected to direct pull by the lever during movement thereof in operating direction for raising the lifting frame.

25. In a lift truck, a main frame, a lifting frame, a ratchet member, means connected to said member and actuated thereby for raising the lifting frame, a lever mounted on the main frame, a ratchet bar movable into and out of operating relation to the ratchet member, and operating connections between the lever and the bar, said bar being sub-- je'cted to straight line pull lengthwise of the truck and the reactive force of the lever being exerted in a straight line and lengthwise of the truck oppositely to the pull on the bar,

when the lever is moved in operating direction for raising the lifting frame.

26. In a lifting truck, a main frame, a lifting frame, an operating lever, and ratchet means for raising the lifting frame, said means including a member connected to the lever and subjected to direct pull thereby.

27. In a lifting truck, a main frame, a lifting frame, an operating lever, and ratchet means for raising the lifting frame, said means including a member connected to the lever and subjected to direct pull thereby in a straight line lengthwise of the truck.

28. In a lift truck, a main frame, a lifting frame, a ratchet member, means connected to said member and actuated thereby for raising the lifting frame, a lever mounted on the main frame, a ratchet bar movable into and out of operating relation to the ratchet member, operating connections between the lever and thebar, hydraulic means for normally holding the lifting frame raised, and means for holding the bar out of engagement with the ratchet member and for operating said hydraulic means to release the lifting frame and'cushion lowering thereof.

ARTHUR M. BARRETT.