US3144137A - Stacker crane - Google Patents

Description

11, 1964 R. VALLIERE ETAL 3,144,137

STACKER CRANE Filed Jan. 30, 1962 4 Sheets-Sheet l FIG] INVENTORS ROBERT L. VALLIERE Y WALTER A. PAULSSEN AT TORNEYS Aug. 11, 1964 R. L. VALLIERE ETAL 3,144,137

STACKER CRANE Filed Jan. 30, 1962 4 Sheets-Sheet 2 INVENTORS ROBERT L VALLIERE WALTER A. FAULSSEN ATTORNEYS Aug. 11, 1964 R. L. VALLIERE ETAL 3,144,137

STACKER CRANE Filed Jan. 30, 1962 4 Sheets-Sheet Z l I l 1 I INVENTORS H64 ROBERT L. VALLIERE Y WALTER A. PAULSSEN AT TO NEYS g- 11, 1964 R. L. VALLlERE ETAL 3,144,137

STACKER CRANE Filed Jan. 30, 1962 4 Sheets-Sheet 4 IN VEN TORS FIG. 5

WALTER A. FAULSSEN www kmw AT TO RNEYS ROBERT L. VALLIERE v United States Patent 3,144,137 STACKER CRANE Robert L. Valiiere, Roosevelt Park, and Walter A. Paulssen, Spring Lake, Mich, assignors to Manning, Maxwell & Moore, Incorporated, Muskegon, MiClL, a corporation of New Jersey Filed Jan. 30, 1962, Ser. No. 169,872 8 Claims. (Cl. 212-128) This invention relates to improvements in a stacker crane, and more particularly to a stacker crane of the type highly desirable for use in warehouses and other storage locations wherein materials of various kinds are stored on vertically disposed shelving, racks or bin assemblies and the like, the crane being utilized for order picking or selection as well as storage, although the invention will have other uses and purposes as will be apparent to one skilled in the art. I

Stacker cranes of the general type of the instant invention usually comprise a mast depending from a trolley which traverses a travelling bridge spanning the area in which the crane operates. Drive means were provided to rotate the mast at least through one revolution. In some instances the mast was a fixed mast and a load carrying assembly travelled up and down the mast, while in other instances the mast comprised telescopic sections, only the uppermost of which was fixed, and a load carrying assembly was mounted on the lower section. In either event, the mast is subject to a bending moment, by virtue of the fact that the load is disposed to one side of the mast seated on a pair of lifting forks or other load holding means. Of course, the mast must be of suflicient strength and so mounted as to overcome this bending moment.

Cranes of this general type heretofore made have proven objectionable owing to their particular construction. Such cranes had the load lifting machinery located on the mast itself, and frequently the means or mechanism for rotating the mast was also located on the mast. Such arrangement resulted in an extremely congested area at the top of the mast, and since all of the live load was initially carried by the mast, extremely heavy thrust bearings and related components had to be used at the top of the mast where the mast connects with the trolley. With structures of this type as heretofore known, a mast with all the machinery located on it at the top thereof was most apt to be mounted on an underhung type or monorail trolley, since if it were connected with a top running trolley the bridge girders would necessarily be spread objectionably far apart in order to accommodate all of the machinery therebetween. Locating most of the machinery within the frame of the mast itself results in adversely affecting the available lifting power, while locating the machinery on the mast but outside of the frame creates a definite problem as to clearances. Obviously,

with the machinery located on the mast near the top thereof the height to which a load may be lifted is necessarily reduced.

With the foregoing in mind, it is an important object of the instant invention to provide a stacker crane having a trolley riding a travelling bridge with a mast depending from the trolley, and so constructed that the entire live load is carried by the trolley and transmitted directly to the bridge rails, the mast being subject only to a bending moment by virtue of the load being off the center line of the mast.

Also an object of this invention is the provision of a stacker crane having a mast depending from a trolley that rides a travelling bridge, with all the hoisting machinery and mast rotating means being carried by the trolley.

It is also an object of this invention to provide a stacker "ice crane having a mast depending from a movable trolley, the structure being such that the trolley may be of the underhung or top running type and yet the girders of the travelling bridge on which the trolley rides may remain at the same distance apart regardless of which type of trolley is utilized.

It is also a feature of this invention to provide a stacker crane embodying a telescoping mast depending from a trolley riding a travelling bridge, and wherein all of the live load including the telescoping mast sections is carried directly by the trolley as distinguished from the mast.

Still another object of the instant invention is the provision of a stacker crane embodying a rotary mast depending from a trolley with all of the lifting machinery mounted on the trolley and with the ropes from the hoisting drum extending downwardly through the central portion of the mast to a lower block which is mounted on a swivel to prevent twisting of the ropes about themselves when the mast is rotated.

It is also a desideratum of this invention to provide a stacker crane having a mast depending from a trolley with load engaging means on the mast connected in a shock absorbing manner with the lift ropes depending from a hoisting drum carried by the trolley.

A further feature of the instant invention is the provision of a stacker crane more economical, more versatile, and permitting a higher lift than stacker cranes heretofore known.

While some of the more salient features, characteristics and advantages of the instant invention have been above pointed out, others will become apparent from the following disclosures, taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a fragmentary side elevational view of a stacker crane embodying principles of the instant inven tion, showing the same associated with a travelling bridge, parts being broken away and parts shown in section;

FIGURE 2 is a fragmentary vertical sectional view through the stacker crane taken substantially as indicated by the staggered section line II-II of FIGURE 1, looking in the direction of the arrows;

FIGURE 3 is an enlarged fragmentary top plan view of the trolley of the crane, taken from the right-hand side of FIGURE 2;

FIGURE 4 is an end view of the upper portion of the crane structure, with parts shown in section;

FIGURE 5 is a plan sectional view taken substantially as indicated by the section line V-V of FIGURE 2; and

FIGURE 6 is an enlarged vertical sectional view, with parts omitted, taken substantially as indicated by the line VI-VI of FIGURE 5.

As Shown on the Drawings With reference now to FIGURES 1 and 2 of the drawings, it will be seen that the illustrated embodiment of the instant invention is shown by Way of example with a trolley of the top running type which traverses a bridge generally indicated by numeral 1 which spans the area in which the stacker crane is to operate. Any suitable form of support may be provided for the ends of the bridge, as indicated at 2-2, which supports each carry a rail 3 thereon upon which the bridge rides by means of wheels 4. The bridge embodies a frame structure including side girders 5-5, along one of which is provided a catwalk 6. On the top of each of the side girders 5--5 and extending lengthwise thereof is a rail 7 on which the trolley of the instant invention rides, as best seen in FIG- URE 4. At this point, it should be noted that with the structure of the instant invention regardless of whether the trolley is of the top running type as shown, or the underhung type, the girders 5-5 of the bridge may be the same distance apart, it not being necessary to increase the spacing between these girders to accommodate a top running trolley as embodied in the instant invention.

The trolley of this invention embodies a frame structure 8 fabricated in any suitable manner, and at each end of this frame structure is a transverse shaft 9 having a wheel 10 on each end thereof, which wheels ride the rails 7-7 on the aforesaid bridge 1. The shafts 9-9 are journalled in suitable bearings as indicated at 11, and it will be understood that all of the shafts are journalled in adequate bearings which will not be fully described herein since they are of standard and known form. The entire trolley traversing, mast rotating, and load elevating machinery is carried on the trolley itself.

For traversing the trolley on the bridge rails 7-7, the trolley carries an electric motor 12 which acts upon the end of one of the shafts 9 through a gear case 13. Power for the motor 12 may be supplied by way of a collector arrangement generally indicated by numeral 14 in FTG- URE 2, the particular electric circuit for energizing all of the motors not being a part of the instant invention, but may be of a known character. The motor 12 is, of course, reversible so that the trolley may move in either direction along the bridge.

Also mounted upon the trolley is a hoist drum 15 around which the load lifting rope is wound. This drum is driven by means of an electric motor 16 acting through a transverse shaft 17, a gear box 18, and thence to the shaft 19 of the drum itself. Adjacent the drum is a rope pulley 20 the axis of which is disposed transversely to the drum axis, and the lifting rope is reeved over this pulley in a manner to be later described.

Also on the trolley is a mast rotating electric motor 21 which acts through a speed reducer 22 having a slip clutch, and on a depending portion of the speed reducer a drive sprocket 23 is mounted.

It will be noted that the motors 12 and 16 and the gear box 18 project laterally beyond the sides of the frame of the trolley and extend laterally over the bridge girders 5-5. If the trolley were mounted in an underhung position on the bridge, this same apparatus would project laterally beneath the girders 5-5. Consequently there is no reason for changing the distance between the bridge girders for either type of trolley. On the other hand, if such mechanism was mounted on the top of the mast itself as has been done heretofore, the bridge girders would necessarily have to be spaced farther apart for a top running trolley than for an underhung trolley.

The trolley also carries means for suspending the mast therefrom which are connected to an underhung portion 24 of the trolley frame, and these means are best seen in FIGURE 4. A supporting ring 25 welded or equivalently secured to the frame portion 24 has bolted to the underside thereof a bearing cage 26 and a bearing retainer 27 for a ball bearing assembly 28. A sprocket 29 is associated with the inner side of the bearing assembly 28, and a cylindrical member 30 is bolted by way of a laterally extending top flange 31 to the underside of the sprocket. This cylindrical member 39 has collector rings 32 on the outer side thereof associated with a fixed collector member 33 associated in the necessary electrical circuits. As seen in FIGURE 2, the cylindrical member 30 has an outwardly extending annular flange 34 on the lower end thereof for supporting the mast. Trained over the sprocket 29 and the aforesaid sprocket 23 on the speed reducer 22 is a roller chain diagrammatically indicated at 35, and when the mast rotating motor 21 is operated in either direction, the member 30 by way of its connection to the sprocket 29 is rotated in the corresponding direction.

The mast itself comprises an upper section 36 the upper end of which is welded or equivalently secured to the bottom flange 34 on the cylindrical member 30, an intermediate or second section 37, and a lower or load carrying section 38. These sections successively increase in transverse area downwardly and are telescopically arranged,

the two lower sections being movable relatively and conjointly, while the upper section is fixed. With reference to FIGURE 5, it will be seen that the upper mast section 36 has the cross-sectional shape of an open sided rectangle, with a transverse flange 39 extending along each edge of the open side. The second section 37 is similarly shaped, but is provided with an inwardly extending flange 46 at each edge of the open side, which flanges 49 overlap the flanges 39 on the upper section. The lower section 38 is similarly shaped, but along each edge of the open side there is an outwardly extending flange 41. In order to facilitate telescoping of the mast sections, the upper section is provided on opposite ends thereof with external longitudinally extending ribs 42-42, and the secend section is provided with a pair of rollers 43 to engage each rib 42 on opposite sides thereof. Likewise, the sec ond section 37 is provided with opposed external ribs 44, and the lower section 38 is provided with a pair of rollers 45 to act against each of these ribs. As indicated in FIGURE 2, the second section may be provided with upper and lower pairs of rollers for each rib, if so desired, as many pairs of rollers being used as may be deemed necessary tostabilize the structure.

The load engaging means are carried by the lower mast section 38, and in the illustrated instance these means are in the form of a pair of lift forks, adjustable as to the space therebetween. The load engaging assembly includes an upper pair of brackets 46-46 and a similar lower pair of brackets 47-47 welded or equivalently secured to the opposed flanges 41-41 on the lower mast section, as best seen in FIGURES 2, 5 and 6. The upper brackets 46-46 carry a fixed sleeve 48 therein and the lower brackets 47-47 carry a fixed sleeve 49 therein. Rotatably mounted in suitable bearings 50-50 secured to the flanges 41-41 of the lower mast section is a tubular shaft 51 having one end externally threaded with right-hand threads as indicated at 52, and the opposite end externally threaded with left-hand threads as indicated at 53. A sprocket 54 is keyed to this shaft, which sprocket is driven by a chain diagrammatically indicated at 55 in FIGURE 5 from a sprocket 56 on a speed reducer 57 actuated by an electric motor 58. The motor and speed reducer are mounted on a suitable bracket 59 attached to the lower mast section in any suitable manner.

A pair of lifting fork asemblies, generally indicated by numerals 60 and 61 are provided, and these are arranged allochirally but otherwise are identical in structure. Each such assembly includes an upright supporting member 62 having upper and lower stationary shafts 63 and 64 extending inwardly therefrom into telescopic engagement with the aforesaid tubes 48 and 49. Centrally thereof the supporting member 62 is provided with a drive nut 65 in engagement with the threads on the respective end of the shaft 51. At the lower end hereof, the supporting member 62 carries a horizontally extending lift fork 66. Actuation of the motor 58, which is a reversible motor, causes the supporting members 62 of the lifting forks to be moved inwardly or outwardly as desired to vary the distance between the two lift forks 66-66, whereby the forks are enabled to adequately support loads of various sizes.

Secured centrally to the .fixed sleeves 48 and 49 is a supporting member 67 having an inwardly extending portion 68 which supports a known type of load cell 69 which automatically gives the weight of any load on the lift forks 66-66. The load cell is disposed in the space within the mast section and is suspended from a lower block 70 by means of a bolt 71. The bolt extends into a cylinder 72 on the load cell 69, which cylinder is closed by a cover 73 and between that cover and a washer 74 at the lower end of the bolt is a compression spring 75, whereby the entire load on the lift forks is carried by the spring 75 so that accurate weight of the load can be obtained and indicated by the load cell. Beneath the head of the bolt inside the block 70 and below the washer 74, bearings 76 and 77 are provided respectively so that the load may rotate relatively to the block 70. Within the block 70 is a pair of sheaves 78 and 79.

With reference to FIGURE 2 it will be seen that the lift rope 80 has both ends anchored to the hoist drum on the trolley in spaced relationship as indicated at 81 and 82. From the anchor point 81, the rope extends downwardly inside the mast sections around the sheave 78, then upwardly and over the sheave on the trolley, downwardly around the sheave 79, and back to the anchor point 82. When the mast is rotated, the lower block 70 remains in the same position by virtue of the swivel connection established by the bolt 71 between this block and the load cell, and consequently the reaches of the lift rope within the mast are not twisted about themselves. Adequate tension on the rope is established by the dead weight of the load engaging assembly, when no load is on the forks.

An operators cab or cage 83 is suspended by an in verted L-shaped bracket 84 having the upper end thereof bolted or equivalently secured as indicated at 85 to the upper end of the intermediate mast section 37, as seen in FIGURE 1. This manner of mounting the operators cage keeps the cage spaced outwardly from the mast so that the lower section of the mast may rise above the cage to the position seen in FIGURE 1, whereby the height of lift for a load is not limited by the operators cage or the operator himself, and the operator is never in danger of striking his head on some portion of the upper structure. This arrangement permits a higher lift by the instant invention than was possible with stacker cranes heretofore made.

It will be understood that adequate safety features, such as automatic braking means in case of rope failure, limit switches, and the like which are of a known character may be installed as desired on the instant stacker crane.

In operation, the instant invention is extremely simple, positive, and effective. The trolley is caused to traverse the bridge until the lift forks are in a position to pick up a load, and the mast is rotated in order to adequately engage that load, if necessary. When the hoist drum is operated the lower section of the mast is elevated until the top of it strikes an abutment 86 on the top of the intermediate section 37, and then the intermediate section is carried along with the lower section to whatever height may be desired, or to the highest possible point shown in FIGURE 1. The mast itself is subject only to a bending moment since the mast does not carry the load, nor does the mast have thereon any of the elevating machinery which is entirely carried by the trolley. The load is automatically weighed when lifted by the forks, the load may be elevated above the operators cab, the mast and load rotated whenever desired without danger of twisting the reaches of the lift rope and operation of the crane for elevating or lowering loads is accomplished with rapidity and accuracy.

It will be understood that modifications and variations may be eifected without departing from the scope of the novel concepts of the present invention.

What we claim as our invention:

1. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley and comprising a plurality of hollow telescoping sections,

load engaging means on the lower section of said mast,

a hoist drum on said trolley,

a lift rope between said drum and said load engaging means and extending through the sections of said mast, and

actuating means for said hoist drum also carried by said trolley.

2. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley, said mast comprising a plurality of hollow telescoping sections of which the upper is the smallest in cross-section and the lower is the largest,

load engaging means carried by the lower mast section and extending thereinto,

a hoist drum on said trolley,

a rope from said drum extending downwardly through the mast sections,

a lower block on said rope inside the lower mast section,

a swivel connection between said block and the extending portion of said load engaging means, and

actuating means for said hoist drum carried by said trolley.

3. In a stacker crane,

a traveling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley and comprising a plurality of hollow telescoping sections,

load engaging means on the lower part of said mast extending inside said mast,

a hoist means on said trolley,

a rope from said hoist means extending through said mast,

and a swivel connection between said rope and said load engaging means inside said mast.

4. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a hollow mast depending from said trolley,

load engaging means on the lower part of said mast,

a load cell connected to said means inside said mast for automatic weighing of a load on said means,

hoisting means on said trolley,

and a rope extending through said mast and connecting said hoisting means and said load cell inside said mast.

5. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley and comprising a plurality of telescopic sections,

load engaging means connected to the lower section of said mast,

an operators cab connected to the top of the next above mast section and spaced from said mast to permit the lower mast section and load engaging means to rise above said cab, and

hoisting means to elevate said load engaging means and telescope said mast.

6. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley and comprising a plurality of telescopic sections,

load engaging means connected to the lower section of said mast,

a bracket connected to the top of the next above section extending outwardly therefrom and downwardly spaced from said mast,

an operators cab suspended from said bracket to one side of said mast to permit the load engaging means on the lower mast section to rise above said cab, and

hoisting means carried by said trolley to elevate said load engaging means and telescope said mast.

7. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley,

7 8 load engaging means on the lower part of said mast, means connecting said swivel to said load cell by way hoisting means on said trolley, of said compression spring. a rope depending from said hoisting means, and Shock absorbing means disposed between and COII- References Cited in the file of this patent nected to said rope and said load engaging means. 5

8. In a stacker crane, UNITED STATES PATENTS a travelling bridge, 951,304 Clark et a1. Mar. 8, 1910 a trolley to traverse said bridge, 1,697,538 Moore Jan. 1, 1929 a mast depending from said trolley, 2,847,131 Miller Aug. 12, 1958 load engaging means on the lower part of said mast, 10 2,933,198 Firestone et a1. Apr. 19, 1960 hoisting means on said ey, 2,947,426 Cotesworth et a1. Aug. 2, 1960 a rope depending from said hoisting means, 2 932 425 Moore May 2 1961 a block on the lower part of said rope,

a swivel on said block, FOREIGN PATENTS a load cell connected to said load engaging means, 15 05 903 Germany Apr. 4 1957 a compression spring, and

Claims (1)

1. IN A STACKER CRANE, A TRAVELLING BRIDGE, A TROLLEY TO TRANSVERSE SAID BRIDGE, A MAST DEPENDING FROM SAID TROLLEY AND COMPRISING A PLURALITY OF HOLLOW TELESCOPING SECTIONS, LOAD ENGAGING MEANS ON THE LOWER SECTION OF SAID MAST, A HOIST DRUM ON SAID TROLLEY, A LIFT ROPE BETWEEN SAID DRUM AND SAID LOAD ENGAGING MEANS AND EXTENDING THROUGH THE SECTIONS OF SAID MAST, AND

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