US2709017A - Side loader attachment for industrial lift trucks - Google Patents

Description

8. l. ULINSKI May 24, 195 5 SIDE LOADER ATTAGBMENT FOR INDUSTRIAL LIFT TRUCKS 3 Sheets-Sheet 1 Filed Sept 5 INVENTOR d m BY ATTORNEY y 4, 1955 a. ULINSKI 2,709,017

SIDE LOADER ATTACHMENT FOR INDUSTRIAL LIFT TRUCKS Filed Sept. 5 1951 3 Sheets-Sheet 2 INVENTOR 'AT-TORNEY ULINSKI May 24, 1955 sIpE 1.0mm ATTACl-MENTFOR mnus'mm, 1.1m- 'mucxs Filed Sept. 5, 1951 3 Sheets-Sheet 3 111:: will INVENTOR 4 ATTORNEY United States Patent SIDE LOADER ATTACHMENT FOR INDUSTRIAL LIFT TRUCKS Bronislaus I. Ulinski, Chicago, IlL, assignor to The Yale & Towne Manufacturing Company, Stamford, Conn., a corporation of Connecticut Application September 5, 1951, Serial No. 245,164

Claims. (Cl. 214-671) This invention relates to industrial lift trucks of the class employed for transporting, stacking, and tiering boxes, bales, loaded pallets and other articles, and more particularly to mechanism that will enable trucks to manipulate loads at the side thereof.

It has been found desirable, in trucks of this general class, to mount the load lifting members at one end of the truck, the engagement of these members with theload being brought about through steered manipulation of the truck. Therefore, when a truck of this class is used in a warehouse, for example, it has heretofore been necessary to sacrifice a part of the storage space in order to provide a sufficiently wide aisle to allow the truck room in which to turn so as to bring its load lifting member into engagement with a load at one side of the aisle. It is the purpose of my invention to provide a truck construction that will extend the zone in which loads may be effectively handled by a truck of this class to include positions offset from the line of travel of the truck, whereby to reduce to a minimum the space that is required for maneuvering the truck itself.

As one feature of my invention, I so mount the load lifting member that it may be turned and thereby directed to engage a load that may be in any one of a number of different positions relatively to the truck. Thus, where the load lifting member is one or more forks, for example, the forks may be directed forwardly to lift a load in the path of the truck, as is conventional, or the forks may be directed through their turning movement toward a load that is located entirely at one side of the truck. In the latter case, the forks are placed in lifting relationship to the load through means that move the forks relatively to the truck, this movement preferably occurring as a thrusting movement of the forks in the direction of their length in any of their particular rotated positions. The rotating and the thrusting movements of the forks serve not only in engaging and releasing the load, but also in rotating and moving the load while it is carried by the forks.

As another feature of my invention, the lifting and lowering movement of the forks may occur in any rotated or laterally moved position that they may assume relatively to the truck, and this lifting and lowering movement preferably is contributed through the usual lifting carriage with which lift trucks are equipped.

A further feature of my invention resides in the means whereby the turning of the load lifting member occurs as a pivotal movement centered at the laterally retracted position of the forks or load lifting member. Since the retracted position of the load lifting member is preferably located on the longitudinal axis of the truck, the load lifting member may therefore be rotated to direct it toward a load disposed at the side of an aisle having a width that is little more than sufficient to permit the passage of the truck. This arrangement is attained by supporting the load lifting member through a pivotal meansthat is located at the retracted position of the load ice lifting member, and that is carried preferably by an overhanging member mounted on the truck.

I have thus outlined rather broadly the more important features of my invention in order that the detailed description thereof that follows may be better understood, and in order that my contribution to the art may be better appreciated. There are, of course, additional features of my invention that will be described hereinafter, and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception on which my disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of my invention. It is important, therefore, that the claims to be granted me shall be of sufficient breadth to prevent the appropriation of my invention by those skilled in the art.

Referring now to the drawings:

Fig. 1 is a plan view of the preferred form of my novel side loader showing the forks rotated and thrust laterally of the truck for picking up a load at the side of an aisle, and also showing in broken lines the forks retracted to withdraw the load to a position in the aisle and aligned with the truck.

Fig. 2 is an end view of the truck of Fig. 1.

Fig. 3 is a side elevation with the forks in a forward position, and the dotted lines showing the forks thrust forwardly.

Pig. 4 is a cross sectional view on lines 4-4 of Figs. 3 and 5, showing the construction of a hydraulic motor that I have provided as an example of a means for rotating the forks.

Fig. 5 is a cross sectional view taken on line 5-5 of Fig. 4, showing the motor and the bearing that provides the pivotal support.

Fig. 6 is a side view of a part of my invention showing the scissors legs for supporting and moving the forks relatively to the rotating support member.

Fig. 7 is a cross-sectional view taken on the line 7-7 of Fig. 6, showing the construction of a hydraulic motor as an example of a means contributing the lateral thrusting movement of the forks.

Figs. 8, 9 and 10 are partial sectional views taken respectively on the lines 88, 99 and 1010 in Fig. 6, showing the end connections of the scissors legs.

Fig. 11 is a diagram showing the arrangement of the conduits whereby fluid is supplied for operating the motors.

In the preferred form of the invention shown in the drawings, I utilize a lift truck T of a known type for carrying and operating my novel side loader indicated generally by the numeral 10. As is customary in trucks of'this general class, the truck T carries at its front end a pair of primary uprights 11 and a pair of secondary uprights 12 that in turn carry a lifting carriage 13. The lifting carriage 13 is guided for vertical movement upon the secondary uprights 12, these secondary uprights being vertically movable in turn upon the primary uprights 11 so as to extend the vertical range of movement of the lifting carriage, the vertical movement being under the control of the operator through a means that may take the form of a hydraulic ram 14 (Fig. 2).

The lifting carriage13of the truck T is equipped with the conventional vertical front plate 15 that serves as a means whereby the load engaging member is attached to the truck for vertical movement upon the truck. The load engaging member in this application is my new side loader 10 and carries a pair of lifting forks 16 forming here the particular load engaging or contacting parts. It will be understood that if the lift truck T were to be utilized in a conventional manner, the forks 16 would be mounted directly upon the vertical front plate 15, and these forks would be thrust into lifting'relation to a load by driving the truck T in a direction against the load. While this conventional mode of operation has provided very efficient handling of loads, it is quite obvious that a truck could not thereby effectively engage loads offset from its line of travel. It will be seen by reference to Fig. l, for example, that when the lift truck T is operated in a relatively narrow aisle, the truck cannot through bodily turning movement bring the forks 16 into effective engagement with a load A at the side of the aisle. By the provision of my novel side loader 10, I have contributed a truck adapted for handling not only loads disposed in the line of travel of the truck, but also loads offset from any particular line of travel.

Referring now to Figs. 1, 2, and 3, the attachment comprises a rigid bearing beam 17 that is adapted to be mounted on the front plate of the lifting carriage l3, and that has the shape of an inverted i. so as to project, forwardly of the truck at a level considerably above the lifting carriage. It will be noted at this point that the bearing beam 17 projects forwardly from the truck a distance sufiicient to locate its outer end in a position centered or approximately centered above the pair of forks 16 when the latter are in their retracted position, as will be further explained hereinafter.

Supported in a depending position below the projecting portion of the bearing beam 17 is a rigid load carrier 18 also in the shape of an inverted L, and mounted for rota tion about a vertical axis by a ball bearing 19 (Fig. 5) at the outer end of the bearing beam 17. The outer race of ball bearing 19 is held in a recess in the underside of bearing beam 17 by a retaining ring 20, while the inner race carries the load carrier 18 through a ring 21. Since the pair of forks 16 is carried by the load carrier 13, these forks will obviously rotate in a horizontal plane on bearing 19 so that they may be directed toward loads disposed in different positions relatively to the truck T.

The forks 16 may, of course, be engaged in a conventional manner with a load by movement of the truck toward the load. In order that the forks 16 may also be brought into lifting engagement with a load without movement of the truck, and particularly with a load A that is offset from the line of travel, as illustrated in Fig. l, I mount the forks 16 through a linkage means that provides for longitudinal thrusting movement of the forks relatively to the load carrier 18. This linkage means utilizes scissors legs formed by rigid pairs of parallel members 22,

23, best seen in Figs. 6 to 10, connected at their intersections by a pivot shaft 24. As may be seen in Fig. 7, flanged bushings are splined on the ends of the pivot shaft 24 and attached to the outer scissors leg members 22 by screws 26, while the inner scissors leg members 23 are pivotally mounted on the bushings 25 whereby to swing relatively to the members 22.

The rear ends of the members 22, 23, that make up the scissors legs are mounted upon a pair of opposed channel members 27 in the vertical leg of the load carrier 18, and the forward ends of the members 22, 23, are connected to a similar pair of opposed channel members 28 forming the sides of a vertical frame 29 that carries the forks 16. The upper ends of the scissors leg members 22, 23, have rollers 30, 31, engaged in the pairs of channel members 27, 28, thereby maintaining the frame 29 vertical as it is projected and retracted relatively to the vertical leg of the load carrier 18, and the lower ends of the scissors leg members 22, 23, are connected to the lower portions of the channel members 27, 28, by pivot pins 32, 33, thereby supporting the vertical frame 29, at a constant elevation as it moves relatively to the load carrier 18. Of course, it is desirable that the scissors legs be capable of retraction to an extreme degree, and therefore the scissors leg members 23 have uninterrupted swinging movement in planes between the members 22, and all of these leg members may be retracted to a position almost entirely between the channel members 27 of the load carrier 18, as will be apparent from Fig. 3.

As a means for mounting the forks 16, the vertical frame 29 is equipped with a vertical front plate 34 that preferably is substantially identical to the front plate 15 on the lifting carriage 13, thereby permitting the use in the attachment 10 of forks or other load lifting members that would otherwise be mounted on the lifting carriage 13. -It will be found convenient to so mount the front plate 34 in the attachment 10 that it will be disposed at the same elevation as the front plate 15, and because the attachment 10 provides extreme retraction of the vertical frame member 22, the front plate 34 may occupy a retracted position that is but a short distance forwardly of the front plate 15. The forks 16 may therefore be supported in very nearly the same position they would occupy if mounted conventionally upon the lifting carriage 13, thus permitting the truck T to be operated, when desired, in substantially a conventional manner.

Returning now to the arrangement whereby the attachmeat 10 provides rotation about a vertical axis, it will be noted that the point of pivotal support as represented by the ball bearing assembly 19 is centered above the forks 16 when the latter are supported in their retracted position by the front plate 34. Although it is not necessary that this centering be precise, and it is not my intention to so limit the invention, this arrangement is nevertheless of importance since it permits the pair of forks 16 to pivot substantially in situ. Consequently, the rotation of the forks, with or without a load thereon, requires little more space than is required for the passage of the truck, and permits very successful operation in a narrow aisle. Thus, whether the forks are loaded or empty, they may be rotated in the aisle so as to be directed through their thrusting movement either forwardly of the truck or in a sideward direction. It will be obvious also that the stresses in the ball bearing assembly 19 will be somewhat reduced by this arrangement, in view of the fact that a load may be carried by the forks 16 in their retracted position with a minimum of eccentric force upon the bearing 19.

It will be understood that the vertical lifting movement of the forks 16 will be brought about by the vertical movement of the lifting carriage 13 upon the truck uprights 12, under the control of the truck operator. The lifting carriage 13 lifts the entire attachment 10, and

. the lifting movement therefore occurs without reference to the rotating or lateral movements of the forks or to the positions in which the forks may he placed by such movements.

The particular construction of the means whereby rotating and lateral movement is imparted to the forks is not important to my invention, and any suitable hy draulic, electric, or even manual means may be employed for this purpose, such means preferably being subicct to close control. by the truck operator. 1 have shown in the drawing one form of operating means whereby the forks may be rotated and also a similar means for effecting the lateral movements of the forks. Thus, referring particularly to Figs. 4 and 5, I provide coaxially within the ball bearing 19, an upper rotary hydraulic ram 35 that is adapted to turn the load carrier 18 relatively to the bearing beam 17. This ram has an annular core 36 that is fixed relatively to the bearing beam 17, and a rotatable cylinder 37 that embraces this core and is keyed to the load carrier 18 through screws 38 (Fig. 4). A piston means 39 is attached to the inner surface of the cylinder 37 so as to move in a circumferential channel 40 in the core. A closure 41 fixed on the core 36 within the channel 40 divides the channel so that fluid pressure applied at either side of said closure will move the piston 39 in either direction in the channel, and thereby will rotate the cylinder 37 and the load carrier 18 to which it is keyed.

In order to move the forks 1 6 laterally, I may provide a lower hydraulic ram 42 on the pivot shaft 24 at the intersection of the scissors legs 22 and 23. This ram S is best seen in Fig. 7 and, excepting for the m'arir'ie'r in which it is mounted, is similar to the upper ram 35 I have described for rotating the forks. In the ram 42, the splined shaft 24 passes through the center of the annular core 36 and has an integral flange 43 keyed to said core through screws 44. The scissors legs 23 are attached, on

the other hand, to the cylinder 37 of the ram 42 by screws 45. The operation of this lower ram thereby causes the scissor legs 23 to swing relatively to the legs 22 and projects or retracts the forks 16 with the vertical frame 29, as the case may be.

As a means through which fluid under pressure may be transmitted to and from the lower ram 42, I have shown in Figs. 5 and 11, a pair of upper and lower swivel joint members 46 and 47 disposed within the annular l core 36 of the upper ram 35. The upper joint member 46 is non-rotating relatively to the bearing beam 17 and has fluid under pressure supplied thereto through conduits 48 (Fig. 11). The fluid passes to or from these conduits through circular grooves 49 in the upper joint member 46, these grooves being always in registry with ports in the lower joint member 47 that rotates with the load carrier 18. These ports are connected to the lower ram through conduits 5i) as will be understood by those acquainted with the art.

It is believed that the operation of my novel side loader will be apparent from the foregoing description. Through my invention I have extended the effective load handling zone of a lift truck from an area in front of the truck to areas laterally offset from the truck. The truck is therefore capable of handling efliciently a load that is in any position that can be approached by the truck without regard to the angle of approach. The invention also affords independent control of the lifting, rotating and lateral movements of the load lifting member so that any of these movements may be accomplished at any stage of the other movements. The operator has at his disposal, therefore, a ,means whereby a substantially universal movement may be imparted to the load lifting member or forks, whether they are loaded or empty. While I have described as embodied in my invention an attachment to be applied to a lift truck, it will be understood that the invention may, through the exercise of ordinary skill, be embodied to advantage in a unitary truck. Further, it is within the scope of the invention to embody a lifting means in the attachment whereby to lift the forks relatively to that part of the attachment which is secured to the truck. Such a lifting means could be provided without difficulty in the vertical frame 29 for example, or in the bearing beam 17 or load carrier 18, and would render the attachment effective when applied to a tractor or non-lifting truck.

I now claim:

1. In a combination of the class described, a truck, uprights on said truck, a lifting carriage mounted for vertical movement on said uprights, a bearing beam mounted on said lifting carriage whereby to move vertically with said lifting carriage, a load carrier mounted on said bearing beam for rotation about a vertical axis spaced outwardly from said truck, a load lifting member, scissors legs mounting said load lifting member on said load carrier for lateral movement relatively to said vertical axis in various directions controlled by therotated posi tion of said load carrier on said bearing beam, means moving said load lifting member through said scissors legs whereby to engage a load offset from said vertical axis and to move a load carried by said load lifting member relatively to said vertical axis, and means moving said lifting carriage vertically on said uprights whereby said load lifting member through its vertical movement Will engage loads attditferent levels and will move loads laterally at different levels in any rotated position to which said load lifting member is turned relatively to said truck.

2. In a truck of the class described, a truck body hav- Cit 8 ing uprights, a carriage moving vertically on said uprights, a bearing beam mounted on the vertically moving carriage and extending longitudinally therefrom, a rotating load carrier having a base portion, means mounting said load carrier for rotation on said bearing beam on a vertical axis spaced longitudinally from said truck body with said base portion in spaced relation to said axis in all rotated positions of the load carrier, a load lifter having an inner part, means mounting said load lifter on the base portion of said rotating load carrier for lateral movement toward and away from said base portion with the inner part of said load lifter moving from a position displaced from one side of said vertical axis to a position similarly displaced on the other side of said vertical axis, and said base portion lying entirely on the side of said axis opposed to that side to which the inner part of said load lifter is moved when said load lifter moves away from said base portion.

3. In a truck of the class described, a truck body, a bearing beam, means mounting said bearing beam on said truck body to extend longitudinally therefrom, a rotating load carrier having a vertical base portion and a horizontal portion, means mounting the horizontal portion of said load carrier for rotation on said bearing beam on a vertical axis spaced longitudinally of said truck body with said base portion always in spaced relation to said axis, a load lifter having an inner part, means mounting said load lifter on the base portion of said rotating load carrier for lateral movement toward and away from said base portion with the inner part of said load lifter moving from a position displaced to one side of said vertical axis to a position similarly displaced on the other side of said vertical axis, and said vertical base portion lying entirely on the side of said axis to which the inner part of said load lifter always moves when said load lifter moves toward said base portion.

4. In a truck of the class described, a truck body, a bearing beam, means mounting said bearing beam on said truck body to extend longitudinally therefrom, a rotating load carrier having a horizontal portion adapted to lie in juxtaposed relation to said beam and a vertical base portion, means mounting the horizontal portion of said load carrier for rotation on said bearing beam on a vertical axis spaced longitudinally from said truck body whereby in one rotated position of said rotating load carrier to bring said vertical base portion in juxtaposed relation to the body of said truck, a load lifter having an inner part, means mounting said load lifter on the base portion of said rotating load carrier for lateral movement of its inner part from a position juxtaposed to said base portion and displaced to one side of said vertical axis when said base portion is in juxtaposition to said truck body to a position similarly displaced on the other side of said vertical axis.

5. In a truck of the class described, a truck body, a bearing beam, means mounting said bearing beam on said truck body to extend longitudinally therefrom leaving a considerable open space between said beam and the ground on which the truck moves, an inverted L-shaped rotating load carrier having a horizontal bearing portion and a vertical base portion, means mounting the horizontal portion of said load carrier for rotation on said bearing beam on a vertical axis spaced longitudinally from said truck with said vertical base portion always in spaced relation to said vertical axis in all rotated positions of said rotating load carrier whereby in one rotated position of said rotating load carrier to bring said vertical base portion in juxtaposed relation to the body of said truck, a load lifter having an inner part, means mounting said load lifter on said base portion for lateral movement of its inner part from a position adjacent to said vertical portion and displaced to one side of said vertical axis to a position similarly displaced on the other side of said vertical axis, and said lifter mounting means lying entirely on one side of said axis.

6 In a combination of the class described, a truck having uprights, a carriage moving vertically on said uprights, a bearing beam mounted on said vertically moving carriagc, said beam extending longitudinally from the carriage and leaving a considerable open space between said beam and the ground in all vertical positions of the carriage on the uprights, a load carrier having a horizontal p r ion in iu tap rel t on o a d beam le sa pa s stan al y open, mea m nti said e d c rrier through its horizontal portion for rotation on said bearing beam on a vertical axis spaced longitudinally om aid ck a oa l te a in n inne end p a downwardly extending portion on said load carrier spaced from said vertical axis, means mounting said load lifter on sai dow a d y endi p o o ai a arrier for movement of its inner end part to and from a PQSiIlD iuxtapc ed d o n y extending P tion, and means for moving said load lifter on its mounting means i a y otat posi ion o a d oa carrier to and from the side of said vertical axis opposed to that side on which said downwardly extending portion lies.

7. In combination of the class described, truck having uprights, a carriage moving vertically on uprights, a bearing beam mounted on the vertically moving carriage and extending longitudinally therefrom leaving a considerable open space between said beam and the ground on which said truck moves, a load carrier having a narrow horizontal portion in juxtaposed relation to said beam leaving said space substantially open, means mounting said load carrier through its horizontal portion for rotation on said bearing beam on a vertical axis spaced longitudinally from said truck, a load lifter having an inner end part, a downwardly extending portion on said load carrier spaced from said vertical axis in all rotated positions of said carrier, means mounting said load lifter on said downwardly extending portion of said load carrier for movement from a position in said vertical axis with its inner end part juxtaposed to said downwardly extending portion to a position away from said vertical axis and said downwardly extending portion, and means for moving said load lifter on its mounting means in any rotated position of said load carrier.

8. In a truck of the class described, a truck body having uprights, a carriage moving vertically on said uprights, a bearing beam mounted on the vertically moving carriage and extending longitudinally from said carriage, a rotating load carrier having a base portion, means mounting said load carrier for rotation on said bearing beam on a vertical axis spaced longitudinally from said truck body with said base portion in spaced relation to said axis in all roto a position similarly displaced on the other side of said vertical axis, and said base portion lying entirely on the side of said axis opposed to that side to which said fork is moved relatively to said base portion.

9.. In a combination of the class described, a truck,

a bearing beam extending longitudinally from said truck leaving a considerable open space between said beam and the ground on which said truck moves, means mounting said bearing beam for vertical movement on said truck, a load carrier having a horizontal portion in juxtaposed relation to said beam leaving said space substantially open, means mounting said load carrier through said horizontal portion for rotation on said bearing beam on a vertical axis spaced longitudinally from said truck, a fork having a rear end, a downwardly extending portion on said load carrier spaced from said vertical axis, means mounting said fork. on said downwardly extending portion of said load carrier for movement of its rear end to and from a position juxtaposed to said downwardly extending portion, and means for moving said fork on its mounting means to and from the side of said vertical axis opposed to that side on which said downwardly extending portion lies.

10. In a combination of the class described, a trunk, no rights on said truck, a lifting carriage mounted for vertical movement on said uprights, a bearing beam mounted on said lifting carriage whereby to move vertically with said lifting carriage, a load carrier mounted on said hearing beam for rotation about a vertical axis spaced outwardly from said truck, a load lifting member, means mounting said load lifting member on said load carrier for lateral movement relatively to said vertical axis in various directions controlled by the rotated position of said load carrier on said bearing beam, means moving said load lifting member on its mounting means relatively to said load carrier whereby to engage a load offset from said vertical axis and to move a load carried by said load lifting member relatively to said vertical axis, and means moving said lifting carriage vertically on said uprights whereby said load lifting member through its vertical movement will engage loads at different levels and will move loads laterally at different levels in any rotated position to which said load lifting member is turned relatively to said truck.

References Cited in the file of this patent UNITED STATES PATENTS 1,526,993 Luce Feb. 17, 1925 1,826,116 Andrews Oct. 6, 1931 1,977,785 Wheelock Oct. 23, 1934 1,978,170 Roesner Oct. 23, 1934 2,068,825 Stevenson Jan. 26, 1937 2,271,624 Cochran Feb. 3, 1942 2,298,196 Cochran Oct. 6, 1942 2,405,893 Leftwich Aug. 13, 1946 2,410,373 Westervelt, Jr. Oct. 29, 1946 2,503,180 Wagner Apr. 4, 1950 2,517,085 Cirillo Aug. 1, 1950 2,574,045 Lapham Nov. 6, 1951 2,591,544 Hegarty Apr. 1, 1952 2,621,811 Lull Dec. 16, 1952 2,646,182 Maas July 21, 1953 FOREIGN PATENTS 690,736 France June 24, 1930 607,146 Great Britain Aug. 26, 1948

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