US2793049A

US2793049A - Stake type bunks

Info

Publication number: US2793049A
Application number: US539230A
Authority: US
Inventors: Irwin C Shotwell
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-10-07
Filing date: 1955-10-07
Publication date: 1957-05-21
Anticipated expiration: 1974-05-21

Description

May 21, 1957 I. c. SHOTWELL STAKE TYPE BUNKS 5 Sheets-Sheet 1 Filed 001;. '7, 1955 INVENTOR. IRWIN C. SHOTWELL ATTORNELY May 21, 1957 c, SHOTWELL 2,793,049

' STAKE, TYPE BUNKS Filed Oct. 7, 1955, 3 Sheets-Sheet 2 INVENTOR. IRWIN. C. SHOTWELL ATTORNEY May 21, 1957 1. c. SHOTWELL STAKE TYPE BUNKS I Filed Oct. 7, 1955 s Sheets-Sheet 3 B 9 INVENTOR. lRWlN C. SHOTWELL United States Patent STAKE TYPE EUR-KS irwin hwshotwell, Aberdeen, Wash. Application 'October 7, 1955, Serial N0. 539,239

8 Clann's. (Cl. 280*145) The present in ention relates "to lo su ortin bunks and shore particularly relates to 'log'sup orting hunks having pivotalstakes mounted atthe' ends thereof fo'rffaeili'tating the loading and unloading, as well as carrying of logs rfromthe beds of logging trucks, 'trailers,railroad cars and the like. This application is a continuation-inpart of'myeo-pending application "Serial No. 319,733, 'filedNove'mb'er 10, 1952, now abandoned.

The primary object of the invention is to provide a novellocking bar construction and arrangement for the 'st'ake's in a verticalposition while the'bnnk is utilized in hauling"heavy loads or logs and rhelike, which locking bararra'ngement is easily releasable for permitting pi'votin-g movement of thesta'kes 'of the bunk to release the logs from the bunk, and which locking bar arrangement permits "readyresettin'g of the log holding stakes of the bunk to'a'p'os'itionperpendicular to the bunk.

A furtherobject of the invention, and a very important one, is in the provision of a-separate locking bar arrangement for each bunk stake, the locking bar for each stake "being actuated from the opposite end of the bunk from the *stake'thereb'y eliminatingany element of danger to "the workmen which might otherwise result if the pivot :in'g'movement of the stakes were 'contro lled'adjacent their pivot points. 7

Astillfurther object of the inventionis in the provision of a locking bar arrangement which'has relatively "few wearingtparts' an'd whieharrangement may be readily corrected for resetting of the stakes to "a position perpendiculartothe bunk as wear occurs, by the provision of an adjustable wear-compensating means at the major wear point of "the locking bara'rrangement.

A more specific object of the invention, ancillary'to "the primary object, is in the provision of an im roved io'ekirrg bar arrangement for the bunk stakes of bunks of the type exemplified in White Patents2;4'69,023 and $469,093, the improvement including making the locking 'barof anoveltwo-piece construction whereby the pivot point of each locking bar to its associatedstake is inter mediate the ends of the stake and remote from the pivot p'oint'of the stake "to the bunk.

A stillfurther object of the invention, in accordance with the preceding object, is in the provision of a novel b'unk stake construction to be utilized in conjunction with the lockingbar arrangement whereby the tendency of *the stake to -buckle ortwist under the action of heavy loads is :greatly reduced.

The 'novel features that are considered characteristic of the 'tinvention are set forth with particularity in the appended claims. The invention itself, however, both as *to'its organization and its method of operation, together with additional objects and advantages thereof,

2,793,049 Patented May-=21, 11957 2 will best be understood from the following description of a specific embodiment when read'in connection with-the accompanying drawings, wherein like reference characters indicate like parts through the several figures and in which:

Figure 1 is a top view of a bunk constructed in accordance with the present invention;

Figure 2 is an end elevational view on an enlarged scale of one endportion of the bunk disclose-din the pivotal stake mounting thereof taken generally along the plane of section line 22 of Fig. 5

Figure Sis an enlarged cross sectional View taken substantially-along the plane of section line 3 -3 of Fig. 5;

Figure 4 is aperspective view of one of the stakes, Iper se ,removed from the bunk;

Figure "5 is a cross sectional view taken substantially along the plane of section line 55 of Fig. 1 and showing he locking bar construction for holding the stakes in log carrying osition; t

Figure 6 is a view similar to Fig. '5 and showing one of the stakes "in dumping position;

Figure 7 is an enlarged fragmentary, cross-seotional view of a modified locking barrnechanismfor'the bunk stakes;

, Figure 8 is a topplan view of apreferred modification of a stake type hunk constructed in accordance with the present invention;

a Figure 9 is an enlarged cross-sectionalview taken silhstantially along the plane of section line 9- 9'of-Fig. 8;

Figure 10is a view similar to Fig. 9 and showing a stake released and pivoted about the end of the brink;

Figure 11 is 2th "enlarged "Cross sectional view "taktflii siihstaiitially along the plane of line 11-1'1 "of Fig. 10, and

Figure 12 is an enlarged fragmentary view in perspective of one of the links of the locking bar-"with'the'wear- "compensating means therefor.

Referring first to the embodiment of the invention dis- Zzlosed in Figs. l-'-7, a log-supporting bunk 1, in essence, comprises an elongated, hollow cross-beam adapted to be disposed crosswise on a vehicle bed for supporting logfs thereon. Depending from the ends of the bunk 1 antioxtending downwardly therefrom are supporting brackets 5. The lower ends of bunk stakes 2 ends, which normally extend perpendicularly above the bunk for preventi'n'g logs f'rom rolling oh the bunk, are pivoted to th'elowe'r ends or the brackets 5 by pins 4. A locking har 6 connected by a pivot 7 to each stake, extending longitudirial-1y through the'cross-beam 1 and housed therein, normally maintainseach of the stakes in an upri'ght log reraining position, 'as shown in Figs. 1 and 5.

Each of the locking bars6 is composed of two elements or

1inks

9 and 10 connected at their inner ends t'o'one another by a pivot 11. Pins 1 1a extend "transversely across the cross beam l and have rollers 12 thereon in rolling engagement with the underside of the link element "10 of each'iockin'g bar *6. Additionally,rollers'7a are mount "edtin pairs on opposite sides of the links 10 on pins "8 "carried by the free or outboard ends of the links lil. The rollers 7a, when the

stakes

2 and 3 are in upright position, seat behind abutment "shoulders 15 formed on one end of cam plates 14 mounted within the crossbeam 1. When in this position, as shown in Fig. 5-,'the links 9 and10 of the locking bars 6 are in general longit'udinal alignment with one another with the 'free ends of the links 9 pivoted respectively to intermediate ortions of the

stakes

2 and 3 intermediate the upper and lower 'ends thereof and remote from the pivotal attachments '4 'of the

stakes

2 and 3 to the bunkl.

To maintain the locking bar "6 in its stake-retaining position, theend of the bunk 1 opposite the end to which the respective stake is pivoted has a transverse "pin "1 7 its vertical position.

extending through the side wall thereof. Keyed on each pin 17 is a locking lug 16 which, in its pendant position, abuts the upper surface of the link adjacent the free end thereof to maintain the rollers 7a locked behind the abutment shoulder of the cam plate 14. A crank 18 (Fig. 2) disposed exteriorly of the cross-beam 1 and 'fixed to the pin 17, serves as a means for rotating the pin and swinging the locking lug 16 out of locking position, whereby the rollers 7a may be lifted out of engagement with the abutment shoulder 15 of the cam plate 14 by the lifting action of a pinch bar or the like in a notch 19 in the extreme free end of the link 10.

Upon release of the rollers 7a from their abutment with the abutment shoulder 15, the pressure of the logs against the respective stake causes the stake to pivot about its pivot point 4 as shown in Fig. 6, and swing down to a position approximately 180 removed from its holding position. As the stake swings downwardly, in the direction of the arrow of Fig. 6, the rollers 7a ride over the cam plate 14 and the link 10 rides over the roller 12. Thus, as the locking bar 6 moves outwardly from the end of the bunk to which its associated stake is pivoted,

the articulated connection 11 of the

links

9 and 10 per- "mits the link 9 to swing downwardly in response to the downward swinging movement of the stake.

and the locking bar 6, enabling the locking bar 6 to exert maximum leverage to maintain the

stakes

2 and 3 in their vertical positions when the bunk 1 is carrying a load.

By virtue of the utilization of the articulated locking bar .6 enabling the spacing of the

pivots

4 and 7 of the

stakes

2 and 3, one of the long-standing problems in the art relating to bunks of the nature set forth in the White patents, previously noted, has been solved. Heretofore, the pivot points of the stakes to the bunks and of the locking bars to the stakes have been relatively closely positions, if not identical to one another, which creates tremendous shearing stresses adjacent these pivots and ,not only greatly reduces the active life of the bunks from that desired, but which also quickly causes malfunctioning of the stakes upon attempting to reset them to their vertical positions or to release them for pivoting action for loading or unloading the bunk.

Referring now to Fig. 7, there is shown a slight modification of the invention wherein a stake 50 is pivotally mounted at one end adjacent the lower edge of a bunk 51 on a pivot 52 extending transversely across the bunk. Fixedly attached to the pivot 52 is one end 54 of a flat,

helical return spring 53, the other end of the return spring 53 seating behind a pin 57 spanning the stake 50 above the pivot 52. Consequently, whenthe stake 50 .is swung down, the spring 53 serves as a counter-balancing agent in assisting in swinging the stake back up to In order to effectively secure the end 54 of the spring 53 in the pivot 52, this pivot 52 is provided with a diametrical slot 55 in which the end 54 is seated.

This figure also shows another adaptation of the articulated locknig bar 6 in that in this modification, the link 9 is considerably shortened over that shown in Figs. l-6, this arrangement sometimes being necessary to'clear the wheels of the logging trailer as the stake is swung downwardly to dumping or unloading position; Further, a bearing member, specifically a roller 59 is mounted above the roller 12 so that the locking bar link 10 rides between the

rollers

59 and 12 rather than just over the roller 12, as in the previous modification. This bear- ,posite the end 86 thereof, the bunk 60 is provided with .a vertical stop plate 92. Thus, when locking lug 90 is lug member or roller 59, and the roller 12, are positioned to engage the link 10 adjacent its articulation 11 to depress the locking bar and draw the stake into upright position.

In Figs. 8-12, the preferred construction of the bunk of the present invention is disclosed with the bunk constituting an elongated, hollow cross-beam 60, similar to the bunk 1 of Fig. 1 and having vertically extending stakes 62 at the opposite ends thereof. As will be noted, particularly from Figs. 9 and 11, each of the stakes 62 comprises a pair of parallel, elongated fiat bars 64 which are spaced from and connected to one another by means of a transverse web or cover 66. This cover 66 extends substantially thev length of the stakes 62 along the outer sides thereof but terminates considerably above the lower end of each stake on the inner side thereof for a purpose which will become immediately apparent. The web 66 extending down toward the pivotal attachment of the stake 62 to the bunk 60 serves to greatly reinforce the side walls 64 of the stake against buckling or bending, particularly the lower ends of the side walls 64, which interferes with the swinging action of the stakes.

A pivot pin 68 extends transversely across the bunk 60 at each end adjacent the lower edge thereof and swingably mounts one of the stakes 62 thereon. In this embodiment, as in that of Fig. 7, there are no supporting brackets depending below the major plane of the'bunk 60 for the attachment of the stake. However, in order to afford considerable longitudinal spacing along the stake between the pivotal attachment of the stake to the

pins

68 and 70, the top wall of the bunk 60 adjacent the stake is cut away so that the adjacent link of an articulated locking bar 72 may project thereabove.

A will be noted, particularly in Fig. 9, the articulated locking bar 72 comprises an elongated link 74 and a relatively shorter link 76. The inner ends of these links are joined to one another by means of pivot pin 78. Upper and lower bearing members or pins and 82, respectively extending transversely across the bunk 60, confine the elongated link 74 therebetween adjacent the pivot pin 78. The shorter link 76 normally extends upwardly at an angle from its pivotal connection 78 with the link 74 to its pivot connection 70 with the stake 62. This upwardly angled extension of the link 76 is made possible, of course, by cutting away the top wall of the bunk 60 adjacent the stake, as noted previously, to provide the maximum possible longitudinal distance along the stake between the

pivots

68 and 70.

Mounted within the bunk 60 adjacent the end thereof opposite each associated stake 62 is a pair of parallel, elongated, horizontally disposed plates 84, the remote ends 86 thereof providing an abutment shoulder for the free end of the link 74. Rollers 88 at the free end of each link 74 normally seat behind and against the abutment shoulder 86 of each plate 84'with the link 74 being guidably disposed between the plates. Lug 90 bearing down on the upper surface of each link 74 adjacent the free end thereof normally holds the rollers 88 in abutment with the abutment shoulder 86.

Adjacent the end of one of each pair of plates 84 oprotated out of its locking position shown in Fig. 10 and the pinch bar inserted in the end of the bunk 60 to lift the free end of the link 74 out of engagement with abutment shoulder 86, the articulated locking bar 72 moves outwardly beyond the opposite end of the bunk 60 as the bunk stake swings downwardly with link 76 swinging downwardly along with the downward swinging movement of its associated stake 62. Vertical plate 92 serves as a safety stop for abutment thereagainst by one of the rollers 88 of the link 74 to limit the outward extension of the locking bar 72 from the end of the bunk' 60.

Intermediate the ends thereof, the link 74 is provided with an upstanding lug 94 to which one end of an elongated spasm coil spring is attached. The other end of the -coiltspring 96 is anchored to the end portion of. the bunk 60,.as] by a bracket 98, opposite the stake.62 .with which thepar- .ticular locking bar link 74 is associated. As thetstake .62 :swings downwardly, the spring 96 .iszthus istretched so that it serves to assist in returning the stake to its upright position shown in Fig. 9. By positioning the spring at the particular point shown, it is protected against the weather and also against other outside forces which would tend to aiiect the resilience thereof. Further, the spring is provided at the point where it exerts the greatest leverage in returning the associated stake 62 to its upright position.

Inasmuch as the greatest wear point on the apparatus is that point wherein the inner end of the link 74 underlies pin 89, a wear compensating structure or plate 100 is provided on the upper surface of the link 74 at this point. Gbviously, the engagement of this wear plate 100 with pin 80 governs the normal position of the stake relative to the bunk 60. Preferably, the wear plate 100 consists of a plurality of shims welded to one another to provide a built-up wear compensating formation. Therefore, as the wear plate 100 wears, the normal vertical position of the associated stake 62 may be maintained simply and easily by merely welding additional shims to the wear plate to replace those worn away. Thus, the locking bar link 74 itself is not affected at this wear point and consequently it is a simple matter to maintain the proper relation of the stake 62 to the bunk 60. The utilization of this plate extends the successful life of the bunk long beyond the normal life expectancy of such bunks, a vital factor in the commercial application of the bunk.

Although a certain specific embodiment of the invention has been shown and described, it is obvious that many modifications thereof are possible. The invention, therefore, is not to be restricted except in so far as is necessitated by the prior art and by the spirit of the appended claims.

What I claim is:

1. A stake bunk comprising a hollow bunk having a block provided with a cam surface on its inner end, an abutment at its outer end, a bracket depending from one end of the bunk, a stake pivoted to the lower end of the bracket, a bar disposed longitudinally in said bunk, a link connecting said bar with said stake, said bar and link extending substantially the entire length of the bunk when the stake is in an upright position, said link being pivoted to the stake a substantial distance from the pivot of: the stake to the bunk, a roller on the free end of said bar, the block being in the path of the bar to engage the cam when elevating the stake, the roller dropping behind the abutment when the stake is in elevated position, and a lock located inside the bunk to hold the roller behind the abutment to retain the stake in elevated position and the bar and link in longitudinal alignment within the bunk.

2. A stake bunk as defined in claim 1, wherein the bunk is provided with rollers over which the bar travels when the stake is raised or lowered.

3. A stake bunk, comprising a hollow bunk, a block within the bunk adjacent one end thereof, said block having an abutment at its outer end, a stake pivoted to the end of the bunk opposite said block and adjacent the lower edge thereof, and latch means disposed longitudinally in said bunk and extending substantially the entire length of the bunk when said stake is in upright position for latching cooperation with said block, said latch means including a bar, a roller on the end of said bar opposite said stake for rolling over said block and dropping behind said abutment when the stake is in elevated position, a lock in said bunk to engage the bar and hold the roller behind said abutment to retain the stake in elevated position, and a link connecting said bar with said stake and having its pivotal connection with said stake spaced longitudinally of said stake from the pivot mounting said stake on said burikandfbeingllocated adjacent the upper edge of said bunk when said stake is upright; the lower end of the-stakebeing .bifurcatedsto accommodate said link whenthe stake .is lowered, and means extending between the bifurcations for spacingsaid bifurcations with the stake pivotproviding a bearing forlsaid li'nk whereby distortion of the bifurcations by pressure from a log on said bunk is prevented.

4. A stake bunk as defined in claim 3 comprising a bearing member extending across said bunk and positioned to engage the upper surface of the end of said bar adjacent its connection with said link to depress said bar and draw the stake into upright position.

5. A stake bunk as defined in claim 4 comprising wear means on said bar and engageable with said bearing memher.

6. A log supporting structure comprising an elongated, hollow bunk, a stake pivoted at its lower end to one end of said bunk adjacent the bottom of said bunk for swinging movement between an upright position for holding logs on the bunk and a lowered position permitting dumping of logs from the bunk, locking means for holding said stake upright comprising a locking bar disposed longitudinally within said bunk, said locking bar comprising first and second link members pivotally connected to one another at their adjacent ends, the free end of said first member being pivotally connected to said stake intermediate the ends of the stake, means within said bunk forming an abutment shoulder adjacent the other end of said bunk, means on the free end of said second member engaging said shoulder to lock said stake in an upright position, a lock carried by said bunk adjacent said other end thereof normally maintaining said free end mounted means in engagement with said abutment shoulder, a cross pin within said bunk bearing on the top of said second link member, a wear compensating plate mounted on said top surface of said second link member and upon which said cross pin normally bears when said stake is in an upright position.

7. A log supporting structure according to claim 6 wherein said wear compensating plate comprises a plurality of shims welded in superimposed relation on said second link member.

8. A log supporting structure comprising an elongated, hollow bunk, a state pivoted at its lower end to one end of said bunk adjacent the bottom of said bunk for swinging movement between an upright position for holding logs on the bunk and a lowered position permitting dumping of logs from the bunk, locking means for bolding said stake upright comprising a locking bar disposed longitudinally within said bunk, said locking bar comprising first and second link members pivotally connected to one another at their adjacent ends, the free end of said first member being pivotally connected to said stake intermediate the ends of the stake, means within said bunk forming an abutment shoulder adjacent the other end of said bunk, means on the free end of said second member engaging said shoulder to lock said stake in an upright position, a lock carried by said bunk adjacent said other end thereof normally maintaining said free end mounted means in engagement with said abutment shoulder, a cross pin within said bunk bearing on the top of said second link member, a Wear compensating plate mounted on said top surface of said second link member and upon which said cross pin normally bears when said stake is in an upright position, said stake comprising a pair of spaced, parallel, fiat bars, cross pins joining said fiat bars to one another at their lower ends and at a point intermediate their lower ends, the lower of said cross pins pivotally attaching said stake to said one end of said bunk, said first link being pivotally attached to the upper of said cross pins, a web bridging the space between said flat bars and attached to the peripheral edges thereof beginning at the bottom of said bars, extending upwardly along the outer edges of said bars, then down- 7 8 wardly along the inner edge of said bars to a terminal 2,469,023 White May 3, 1949 point above said'upper cross pin. 2,469,093 White May 3, 1949 j 2,495,898 King Jan. 31, 1950 References Cited in the file of this patent 2,518,974 Busenius Aug, 15, 1950 UNITED STATES PATENTS 5 2,559,007 Clifie --Ju1y 31, 1951 1,471,830 Corey -4 Oct. 23, 1923 2719'729' gemkm 1955