US2873874A

US2873874A - Pole handling apparatus

Info

Publication number: US2873874A
Application number: US668709A
Authority: US
Inventors: Charles W Best; Joe T Napier; Jess F Macmurray
Original assignee: JH Baxter and Co
Current assignee: JH Baxter and Co
Priority date: 1957-06-28
Filing date: 1957-06-28
Publication date: 1959-02-17
Anticipated expiration: 1976-02-17

Description

Feb. 17, 1959 c. w. BEST EI'AL POLE HANDLING APPARATUS 2 Sheets-Sheet 1 Filed June 28, 1957 INVENTORS CHARLES W BEST JOE T NAP/El? JESS F M MURRAV WZJ, M-J

ATTOANEKS Feb. 17, 1959 c. w. BEST ETAL 2,873,874

POLE HANDLING APPARATUS Filed June 28, 1957 2 Sheets-Sheet 2 INVENTORS CHARLES W BEST JOE 7. NAP/ER JESS E M MURRAV "M, 7%% WM A T TO/PNEVS United States Patent POLE HANDLING APPARATUS Charles W. Best, Lafayette, Joe T. Napier, Camarillo, and Jess F. MacMurray, Alameda, Calif, assignors to J. H. Baxter & Co., San Francisco, Calif, acorporation Application June 28, 1957, Serial No. 668,709

4 Claims. (Cl. 214-654) This invention relates to pole handling apparatus and more particularly to an attachment for a fork lift carrier which will adapt the same for handling poles, logs, and the like with greater ease.

Conventional fork lift carriers have often been used for loading, unloading and otherwise handling elongated objects such as logs and telephone poles. The carriers herein referred to are the type having a pair of L-shaped forks upon which the load is balanced, the forks being mounted on a vehicle so that the load may be transported from place to place. Fork lift carriers may be used in such locations as loading and unloading docks and the yards of log or pole processors for handling logs during processing or for general transportation duties.

In handling elongated cylindrical objects such as telephone poles there is of course, the tendency of the pole, which is balanced across the pair of forks, to roll on the lower leg or load supporting surface of the forks. It has therefore been the necessary practice to tilt the forks back toward the vehicle so that a load of poles may be transported thereby. It has also been found that the number of objects of this type which can be successfully transported by a fork lift vehicle is severely restricted because of their tendency to roll off the end of the forks.

Attachments known as log kickers have heretofore been added to a fork lift carrier for the purpose of ejecting the load from the forks. These log kickers, however, in no Way assist in supporting or retaining the load on the forks nor in increasing the capacity of the carrier.

It is therefore an object of this invention to provide a device for a fork lift carrier which will increase the usefullness of the carrier in handling objects such as poles.

Another object of this invention is the provision of pole handling apparatus which increases the efficiency and load capacity of a fork lift carrier.

It is still another object of this invention to provide, in combination with a fork lift carrier, means for retaining a load on the forks.

Yet another object of thisinvention is the provision of improved hold down means for increasing the effectiveness of a fork lift carrier in handling cylindrical, elongated articles such as logs or telephone poles.

Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawings in which: I

Fig. 1 is a side elevational view of a fork lift carrier including thedevice-of thisinvention, shown unloading a log from a railroad flat car;

Fig. 2 is a perspective view of the front portion of the fork lift carrier of Fig. 1, showing details of the forks, the log kickers, and the hold down device of this invention;

Fig. 3 is an enlarged sectional view as seen generally from line 33 of Fig. 2; and,

Fig. 4 is a side elevational view, similar to Fig. 1 but on an enlarged scale, showing the cooperation of the hold down arms, kickers, and forks in handling a single pole.

2,873,874 Patented Feb. 17-, 1959 The device of this invention is adapted to be used in connection with a fork lift carrier, generally designated 1 (Fig. 1), comprising a ground wheeled vehicle 2 with a fork lift unit, generally designated 3, mounted on the front end thereof. The fork lift unit includes a pair of L-shaped forks 4 having generally horizontal lower legs and mounted on a generally vertical backing member or frame 5 (Fig. 2). The backing member or frame 5 is mounted for movement up and down generally vertically extending posts 6 which are mounted on the front of vehicle 2. I

In the particular fork lift carrier shown herein posts 6 are pivotally mounted at their lower ends on vehicle 2 so as to be tiltable by a linkage 7 (Fig. 1). This, of course, permitsforks 4 and backing member 5 to be tilted as desired although the same are usually generally horizontal and vertical, respectively, as described. It is to be understood that the description of the fork lift carrier is somewhat general since the invention herein described may be attached to any of the various types of fork lift carriers on the market. The description of the fork lift carrier is therefore meant to be merely representative of this type vehicle.

The carrier may also be provided with a so called log kicker or load ejector which comprises a pair of elongated kicker arms 8 mounted on a shaft 9 (Fig. 2) rotatablysupported in bearings at the upper end of backing member 5. Kicker arms 8 may be mounted just outside forks 4 and extend from shaft 9 downwardly toward said forks. A pair of synchronized hydraulic cylinders 10 have their piston rods connected to cranks 11, secured to arms 8, for swinging said arms in generally vertical. arcs outwardly of backing member 5 in the direction of projection of forks 4.

A foot member 12 may be telescopically received in each arm 8 so as to project outwardly of the lower end thereof, and said foot members may be connected by links 13 to backing member 5 so that the lower projecting end of each foot member 12 will move adjacent the load supporting surface of forks 4 as kicker arms 8 are swung outwardly away from backing member 5. In this manner, a load carried by forks 4 may be ejected off the ends thereof by said kicker arms.

In order to facilitate the handling of poles and the like by the previously described fork lift carrier, this invention provides a hold down device, generally designated 16 (Figs. l-3). Said hold down device comprises a pair of elongated arms 17 which are secured to the ends of shaft 18. Shaft 18 is journaled in bearings 19, mounted on backing member 5, so that hold down arms 17 project from said backing member in the general direction of forks 4.

Hold down arms 17 are secured to shaft 18 so that when such shaft is oscillated arms 17 will be caused to swing in generally vertical arcs toward and away from the load supporting surfaces of forks 4, as indicated by arrows 20 (Figs. 2, 3). The outer free end portions 21 of hold down arms 17 are formed to a smaller cross section than the remaining portions of said hold down arms was to provide greater flexibility in said. outer end portions. This, coupled with the fact that the free ends are curved downwardly, as at '22, facilitates retention of the load on the forks 4 by said hold down arms.

Power means are connected to shaft 18 to provide the above mentioned swinging of arms 17, and said power means comprises a spur gear 23 (Figs. 2, 3) secured on shaft 18 and in mesh with an oscillatable rack 24. Rack 24 may be reciprocated in the direction of arrow 25 by a hydraulic cylinder 26 (Fig. 3) having a piston therein with its rod 27 connected to rack 24. Cylinder 26 may be pivotally connected to backing member 5, as shown in Fig. 3 and the connection between rod 27 and rack 24 may also be made sufficiently free to prevent binding. A housing 28 may be provided acting both as a guard for gear 23 and as a guide for the back of rack 24 to keep the same in mesh with said gear.

A four-way control valve 29 may be provided in the vehicle cab for controlling the flow of hydraulic oil from a reservoir 30 through a pump 31 to and from hydraulic cylinder 26. In the solid line position shown in Fig. 3 valve 29 routes the oil under pressure from pump 31 to the lower end of cylinder 26 causing the piston therein to rise, moving rack 24 upwardly thereby swinging arms 17 downwardly. Movement of the valve vane 32 in the direction arrow 33 to the dot-line position would, of course, reverse the flow of the oil and thereby the direction of movement of hold down arms 17.

It will be noted that a single hold down arm 17 will perform the task of holding a load, such pole 34 (Fig. 1) on forks 4. However, it is deemed preferable to provide at least a pair of arms 17 spaced apart as shown for greater stability. It is also preferable, as seen in Fig. 2, that hold down arms 17 are mounted inside forks 4 whereas kicker arms 8 are generally mounted slightly outwardly of said forks.

The hold down device of this invention, working in combination with a work lift carrier, with or without kicker arms, provides substantially greater utility and load carrying capacity for such carrier. For example, a single pole 34 may be selected from a load on a flat car 35 as illustrated in Fig. 1. If the forks are tilted downwardly (Fig. 1) the pole 34 will be held near the outer end thereof by the hold down device 16. In handling a single pole the kicker arms 8 may be positioned so that in combination with the hold down arms 17 the pole is held onv the outer end of forks as shown in Fig. 4.

In the absence of the hold down device of this in vention only a relatively small load of poles may be handled by a conventional fork lift carrier and, in such case, it is necessary that the forks 4 always be tilted back toward the vehicle 2. It is therefore, particularly diflicult to pick up any substantial number of logs or poles from a stack with a conventional fork lift carrier.

Withhold down device 16, it is possible to insert forks 4 slanting downwardly into a stack of poles or the like. and to pick up and retain a substantial number of said poles on the forks by means of hold down arms 17. It is also possible to eject only a portion of a complete load of poles while still retaining the remainder by urging some of the poles to the outer ends of forks 4 out from under arms 17 with kickers 8.

The range of operation of a fork lift carrier provided with the hold down device 16 of this invention is greatly increased since it is not necessary to tilt the forks back toward the vehicle in order to retain the load thereon. The fork lift carrier may therefore be used to reach farther to pick up or discharge a load as shown in Fig. 1.

Although the invention has been described and illustrated in detail it is obvious that modifications could be made therein without departing from the spirit and scope intended.

We claim:

1. In combination with a fork lift carrier having a pair of generally horizontal, load-supporting forks projecting from one side of a generally vertical backing member and a pair of kicker arms movable along said forks for ejecting a load therefrom, a hold down device, comprising: a pair of elongated, spaced hold down arms projecting from said one side of said backing member and swingably mounted thereon at a location spaced upwardly from said forks for swinging in generally vertical arcs toward and away from said forks, and power means connected to said arms for so swinging the same, whereby an elongated load may be held at the outer end of said forks by said kicker arms and said hold down, the outer free ends of said hold down arms being curved toward said forks.

2. In combination with a fork lift carrier having a pair of generally horizontal, load-supporting forks projecting from one side of a generally vertical backing member and a pair of kicker arms movable along said forks for ejecting a load therefrom, a hold down device, comprising: a pair of elongated, spaced hold down arms projecting from said one side of said backing member and swingably mounted thereon at a location spaced upwardly from said forks for swinging in generally vertical arcs toward and away from said forks, and power means connected to said arms for so swinging the same, whereby an elongated load may be held at the outer end of said forks by said kicker arms and said hold down, the outer free ends of said hold down arms being curved toward said forks, and the end portions of said arms adjacent said free ends being more flexible than the remaining portions of said arms.

3. In combination with a fork lift carrier having a pair of generally horizontal, load-supporting forks projecting from one side of a generally vertical backing member and a pair of kicker arms movable along said forks for ejecting a load therefrom, a hold down device, comprising: a rotatable shaft mounted on said backing member spaced upwardly from said forks and extending transversely thereof, a pair of elongated, spaced hold down arms secured at one end to said shaft and projecting radially therefrom for swinging toward and away from said forks upon oscillation of the same, said power means including a gear on said shaft, a rack in mesh with said gear, and an hydraulic cylinder connected to said rack for reciprocating said rack.

4. In combination, a fork lift carrier having a pair of generally horizontal load-supporting forks projecting from one side of a generally vertical backing member, a pair of power-driven kicker arms movable along said forks for moving a load thereon from said backing member to the outer free ends of said forks, a pair of elongated, spaced, hold down arms projecting from said one side of said backing member and swingably mounted thereon at a location spaced upwardly from said forks for swinging in generally vertical arcs toward and away from said forks, and power means connected to said arms for so swinging the same, whereby an elongated load may be held on said outer free ends of said forks by said kicker arms and said hold down arms.

References Cited in the file of this patent UNITED STATES PATENTS 1,763,351 Gfrorer June 10, 1930 2,418,251 Drott Apr. 1, 1947 2,742,167 Brudi Apr. 17, 1956 2,776,768 Carlson Jan. 8, 1957 2,799,412 Pilch July 16, 1957