Tail gate mechanism for dumping trucks

TAIL GATE MECHANISM FOR DUMPING TRUCKS

July 13, 1954

L. S. WOOD

2,683,545

Filed July 25, 1951

Sheets-Sheet 1

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July 13, 1954 l_ S. WOOD

2,683,545

TAIL GATE MECHANISM FOR DUMPING TRUCKS

Filed July 25, 1951 9 Sheets-Sheet 2

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ATTORNEY

July 13, 1954

L. S. WOOD

2,683,545

TAIL GATE MECHANISM FOR DUMPING TRUCKS

Filed July 25, 1951

Sheets-Sheet 3

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July 13, 1954

L. S. WOOD

2,683,545

<img file="US2683545A_D0004.tif" />

July 13, 1954

L. S. WOOD

2,683,545

TAIL GATE MECHANISM FOR DUMPING TRUCKS

Sheets-Sheet 5

Filed July 25, 1951

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^J^y 13, 1954 ^F0R dumpi_Ng

TAII ^{L S}‘ ^W°OD ^{L GATE} ^ichanism

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2*683,545

TRUCKS

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July 13, 1954

L. S. WOOD

2,683,545

TAIL GATE MECHANISM FOR DUMPING TRUCKS

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Filed July 25, 1951

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BY

ATTORNEY

July 13, 1954

L S. WOOD

2,683,545

TAIL GATE MECHANISM FOR DUMPING TRUCKS

Filed July 25, 1951 9 Sheets-Sheet 8

<img file="US2683545A_D0011.tif" />

July 13, 1954

L. S. WOOD

2,683,545

TAIL GATE MECHANISM FOR DUMPING TRUCKS

<img file="US2683545A_D0012.tif" />

LOUIS S. WOOD

ATTORNEY

Patented July 13, 1954

2,683,545

UNITED STATES PATENT OFFICE

2,683,545

TAIL GATE MECHANISM FOR DUMPING TRUCKS

Louis S. Wood, Detroit, Mich., assignor, by mesne assignments, to L. A. Young Spring &amp; Wire Corporation, Detroit, Mich., a corporation of Michigan

Application July 25, 1951, Serial No. 238,443

Claims.

This invention relates to tail-gate mechanisms for trucks and the like, and more particularly to a power-operated mechanism of this type whereby the tail-gate is adapted to serve as an elevator for raising a burden from ground level to the level of the bed of the truck body.

My Patent No. 2,469,321 of May 3, 1949, is illustrative of this type of power-operated tail-gate, but in embodiments of that invention the truck body is made fast to the chassis of the truck and is incapable of being pivotally moved into and out of dumping position. Yet there seems to be a demand for a power-operated tail-gate on powerdumped trucks, so it is an object of this invention to devise such an apparatus.

Another object is to arrange the tail-gate operating mechanism so that it will not interfere with the power-operated dumping mechanism for the truck body, and it is a further object to arrange the dumping mechanism including the tail-gate details, so that the truck can dump through the tail-gate when in dumping position without interfering with the tail-gate operating mechanism. In other words, it is an object of this invention to arrange the various mechanisms and the design of the tail-gate itself so that the power-operated tail-gate can operate satisfactorily when the truck body is in nondumping position while the truck body dumping mechanism can work and the truck load can dump or cascade through a port in the tail-gate when the truck body is in dumping position and the tail-gate mechanism is inoperative.

It is a still further object of this invention so to arrange and construct the parts that when in load-dumping position, the tiltable body clears all of the operating parts and yet is depressed so that when in dumping position, the dumping end of the body is much nearer the ground than when in non-dumping position.

It is another object of the invention to provide a novel mechanism for automatically holding the control lever and associated mechanism in operative position as desired until mechanically or manually changed. Utilizing such novel mechanism eliminates the necessity of having to hold the control lever when operating the tail-gate.

With the above and other objects in view, the invention consists in the construction and novel combination and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings and pointed out in the claims hereto appended, it being understood that various changes in the form, proportions, and minor details of construction, within the scope of the (Cl.

214—501) claims, may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

In the drawings—

Fig. 1 is a side elevation of the rear portion of a dumping truck, showing the dumping body in a horizontal position and the tail-gate lowered to the ground in position to receive a load to be transferred into the body of the truck;

Fig. 2 is a similar view showing the tail-gate elevated and in a horizontal position contiguous to and flush relation with the floor of the body of the truck;

Fig. 3 is a side elevation showing the tail-gate closed and latched;

Fig. 4 is a similar view showing the dumping body tilted for dumping and the port-gate of the tail-gate open to permit the contents of the dumping body to cascade through the tail-gate;

Fig. 5 is a rear elevation of the dumping truck, parts being broken away to illustrate the tailgate operating mechanism more clearly;

Fig. 6 is a side elevation on an enlarged scale showing the rear portion of the truck with the tail-gate arranged as shown in Fig. 1;

Fig. 7 is a similar view with the tail-gate arranged as illustrated in Fig. 2;

Fig. 8 is a similar view on an enlarged scale taken from the other side of the dumping truck, parts being broken away for clarity of illustration;

Fig. 9 is a perspective view of the rear portion of the dumping truck with the parts arranged as shown in Fig. 1;

Fig. 10 is an enlarged detail sectional view illustrating the means for holding the dump portgate in its closed position;

Fig. 11 is an enlarged detail perspective view illustrating the latching assembly for locking the dump port-gate in its closed position;

Fig. 12 is an enlarged plan view illustrating the mechanism for operating the tail-gate, a portion of the truck body being shown in dotted lines;

Fig. 13 is a detail vertical sectional view taken on the line 13—13 of Fig. 12;

Fig. 14 is a similar view taken on the line 14— 14 of Fig. 12;

Fig. 15 is an enlarged detail view of the catch controlling mechanism for locking and unlocking the lifting arms of the tail-gate;

Fig. 16 is an elevational view partly in section, illustrating an adjustable pre-loaded valve centering mechanism for holding the valve in a desired operating position until manually or mechanically released;

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Fig. 17 is an end elevation of the mechanism shown in Fig. 16.

In the accompanying drawings, in which is illustrated one embodiment of the invention, the dumping truck is provided with a dumping body I I provided at opposite sides of Its rear end with depending bearing brackets 2 constructed of any suitable material such as flanged metal, consisting of a vertical upper oblong portion 3 and a tapered inclined lower portion 4 ^extending down- 1 wardly and forwardly and provided at its lower end with a bearing '5. The bearings of the brackets 2 receive and have Journaled in them for rotary movement an outer transverse shaft S which has journaled within it for rotary move- ¹ment an inner transverse shaft 7. The outer transverse shaft Ξ is journaled ;in suitable bearings 8 of bearing brackets S located at opposite sides of the truck and secured to the chassis 10 thereof and the lower portions ί ί of the bearing ²brackets 9 extend downwardly and forwardly at an inclination from the upper attached portions of the bearing brackets -9.

The dumping body which pivots on the outer shaft‘6 is tilted from the horizontal position illustrated in Figs. 1 to 3, -inclusive, to the inclined position shown in Fig. 4 by the usual hydraulically operated means including spaced cylinders located at opposite sides of the chassis of the truck and arranged at an inclination and pivoted ³at their lower ends at 14 to depending bearing brackets i5 secured to the chassis of the truck, as clearly illustrated in Figs. 1 to 4, inclusive. The piston f S' of each cylinder 13 is pivotally connected at 16 to the dumping body at the bot- ³tom thereof below the upper face of the floor of the same. The hydraulic power means for operating the dumping body is of the usual conventional means and is -valve controlled within the cab of the truck and further illustration and ' description of the power means for operating the dumping body are believed to be unnecessary as the dumping body operates in the usual manner and is tilted from its normal horizontal position to an inclined dumping position and automati- -1 cally returns to its initial horizontal position after the discharge of its contents when the piston 15' is relieved of hydraulic pressure in the usual manner.

The particular means for pivotally mounting 5 the dumping body is important as the dumping body is pivotally supported from the same duplex shaft that depends from the chassis and not from the body, consisting of the inner shaft 7 and the outer shaft 6 and from which the tail-gate (7 '&gt; is entirely operated in all of its positions and about which the body f is tiltable or dumpable. Also but secondarily important are the construction and arrangement of the brackets which tiltably support the rear end of the dumping G body from said shaft which permit the body when in dumping position to clear the other parts of the truck, whereby the dumping end of the body can closely approach the ground.

Details of tail-gate raising and lowering mechanism

While the invention is directed primarily to a power-operated tail-gate capable of being applied to a dump-body and provided with an inde- 7 pendently operable dumping inner or port-gate 18 in the main tail-gate 17, it also includes a number of features that cooperate to make such a combination operable satisfactorily. In my preferred embodiment of this invention the tail-gate 7 raising and lowering mechanism on the one hand and on the other hand the tail-gate operating mechanism to move it between the horizontal and vertical positions, both function from said duplex ’ operating shaft that has one shaft concentrically arranged within the other in a way that rotation of the outer shaft causes the raising and lowering of the power tail-gate while the rotation of the inner shaft causes movement of the tail-gate 0 between the horizontal and vertical. So, in obtaining the object of this invention, this duplex shaft that extends transversely of the truck must be operatively supported from the truck chassis ;at an .elevation below the top of the chassis and ³ sufficiently inboard from the tail-gate so that there is no interference of these mechanisms with the full dumping operation of the truck body and the tail-gate. This is accomplished by the angle or knee-shaped brackets 2 which must be long ° enough to provide for the support of a cylinder 4 9 and its mechanism for swinging the tail-gate between horizontal and vertical while at the same time making unnecessary too long a reach between the inner of the concentric shafts and the ³ tail-gate.

The outer shaft 6 is provided at its central portion vzith a pair of arms 23 extending upwardly and rearwardly at an inclination when the tailgate is in its lowered position, as illustrated in ⁰ Figs. 6 and 9, and having secured between their outer ends by a pivot 2 ί the outer end of a piston 22 of a cylinder 23 arranged at an inclination and extending downwardly and rearwardly from the truck body ί and connected at its upper ³ end to the same by a suitable pivot 24 at a point below the upper face of the bottom of the truck body.

The outer shaft S is also provided adjacent its ends with a pair of lifting arms 25 rigidly con⁰ nected vzith the outer shaft '1 which preferably comprise I-beams or other suitable material having the required strength. The lifting arms 25 are provided at their outer ends with plates 25' rigidly secured to the lifting arms in any suit.» able manner and connected at their outer ends with the tail-gate· adjacent the lower edge thereof by a pivot 2S. When pressurized fluid is introduced into the cylinder 23 for actuating the piston 22, the outer shaft is rotated for oscillating ·') the lifting arms 2a and lowering the tail-gate while horizontal from a position level with the floor of the truck body to the ground or for elevating the tail-gate to return it while still horizontal from its ground position to its elevated ³ position flush with the floor of the body ί of the truck and thus enabling a load to be lifted from the ground and readily transferred into the truck body. Ths lifting arms 25 swing through an arc indicated by the dot-and-dash line 27 of Fig. 6 g and the tail-gate is carried in a substantially horizontal position from one point to the other and vice versa. Therefore it constitutes a platform on which the operator may stand while the load is being transferred from the ground to ³ the body of the truck or from the truck to the ground.

Tail-gate swinging mechanism and operation

The pivot 28 preferably consists of a transverse ° shaft journaled in suitable eyes 28 of the tailgate and it constitutes a pintle on which the tailgate swings in lowering it from a vertical closed position indicated by dotted lines in Figure 7 to the open horizontal position shown in full lines ³ in this figure of the drawings. The ends 2S of

2,683,545 the inner shaft 7 are extended beyond the ends of the outer shaft 6 and are provided with terminal oppositely extended radially disposed arms 38 which are connected by pivots 3! to the adjacent ends of the pair of spaced parallel links 32 preferably consisting of flat bars connected by pivots 33 to the hinged lower or inner edge of the tail-gate at opposite sides of the pintle or pivot shaft 26. The inner shaft is adapted to be rotated to carry the arms 39 through an arc of approximately 45° and this motion is transmitted by the parallel links 32 to the tail-gate which is adapted to be swung downwardly from the vertical dotted line position shown in Fig. 7 to the horizontal position illustrated in full lines in said figure and also to be swung upwardly from the full line horizontal position shown in Fig. 7 to its vertical closed position illustrated in dotted lines in said figure. Any other suitable link connection may, of course, be provided for transmitting motion from the inner shaft to the tail-gate and swinging the gate on its horizontal shaft or pintle 26.

This rotary movement of the inner shaft 7 is effected by a piston 34 operating in the cylinder 19 extending longitudinally of one of the angle bearing brackets 2 of the body I and arranged at a slight inclination and connected at its upper end by a suitable pivot 35 to the bracket 2 on which it is mounted. The lower end of the piston 33 is connected by a pivot 36 to an angle arm 37 fixed to the adjacent outer extended end of the inner shaft 7 and extending downwardly and rearwardly therefrom, as clearly illustrated in Fig. 7 of the drawing.

The tail-gate 17 and the dump or port-gate ! 8 are operable as a unit in swinging the tail-gate from a vertical to a horizontal position to open it, and also when lowering the tail-gate from an elevated horizontal position contiguous to the floor of the body of the truck to the ground and while elevating the tail-gate to said horizontal position and also while swinging the tail-gate from said horizontal position to its vertical closed position. The tail-gate unit comprises a frame composed of spaced parallel side portions 38 and a connecting bottom portion 39 and the dump or port-gate st consists of a panel connected at its upper edge to the upper ends of the sides 38 by suitable pivots 49, but the panel may be pivoted within the frame of the tail-gate in any other suitable manner. The inner ends of the sides -38 and the lower edge of the connecting bottom portion 39 of the frame of the tail-gate are arranged flush with the inner faces of the side walls of the body and the bottom of the body when the tail-gate is closed so that when the body is tilted to its dumping position and the port-gate is unlatched, the entire contents of the body of the truck may be discharged through the opening in the tail-gate without any interference by the frame of the tail-gate of the complete discharge of the contents of the truck.

Hydraulic system and valve control mechanism

A hydraulic pump, not shown, adapted to be driven by any suitable means, as by the motor of the truck, is connected to each of a pair of hydraulic valves 4i and 42 shown in Figures 12, 13 and 14 and supported by a transverse frame member 43 secured to laterally spaced longitudinal frame members 44. The valve 41 communicates by hydraulic lines 45 and 46 with the spaces between the ends of the cylinder 19 and the piston 34 which is connected to the inner shaft 7. The other valve 42 is connected by the hydraulic lines 47 and 48 with spaces between ends of the cylinder 23 and the piston 22 which is connected with the outer shaft 6.

The valves 41 and 42 which may be of any preferred type are preferably constructed substantially the same as those shown and described in said Patent 2,469,321, and when the valve stems 49 and 59 are moved inwardly to the limit of their inward movement they open the valves to connect the cylinders 19 and 23 to the pump and when the valve stems are carried to the limit of their outward movement communication between the cylinders 19 and 23 through the hydraulic lines 45 and 48 with the pump is cut off and the hydraulic lines are placed in communication with a sump for exhausting pressurized fluid from the cylinders and at the same time admitting pressurized fluid to the other end of the cylinder i9 through the hydraulic line 4S for returning the piston to its initial position. The valves, as explained in said patent, may be moved to a position effective to disconnect the pump from the cylinders 19 and 23 and maintain a fluid lock within the cylinders.

It will be understood, as explained in said patent, that the operation of the valve 42 prevents any passage of fluid to the valve 41. Tire stem 49 of the valve 41 may be moved inwardly simultaneously with a similar movement of the stem 56 of the valve 42, but it is only upon outward movement of the latter stem to its outward position that pressurized fluid may flow through the valve to the cylinder 23. Thus the cylinders i9 and 23 may be operated independently of each other but not simultaneously.

The valve stem 49 is connected by a link red 51 with an arm 52 of a transverse control or operating rock shaft 53 journaled in suitable bearings of the frame of the truck body and extending transversely thereof from one side of the truck body to the other side of the same and provided at each end with an operating handle 54. The operating handles 54, which are approximately Lshaped, extend at each side of the truck body to points within easy reach of a person standing at the side of the truck.

The valve stem 50 of the valve 42 is connected by a link rod 55 with an inner depending arm 5S of a transverse rock shaft 57 journaled in suitable bearings of the truck body frame and provided with an outer depending arm 58. The. outer depending arm 58 is connected by a link rod 59 with a depending arm 60 of an operating shaft 61 journaled in suitable bearings of the frame of the truck body and extending across the same and provided at each end with an upwardly extending operating arm or handle 62. The control mechanism for operating the valve stem 59 of the valve 42 is adapted to be operated from either side of the truck.

When the control valve 42 is operated to introduce pressurized fluid into the cylinder 23 for elevating the tail-gate from the ground position shown in Fig. 6 to the dotted line position illustrated in said figure, wherein the tail-gate is still in its horizontal position but flush with the floor of the body of the truck, the tail-gate being automatically stopped in the dotted line position by means operable by the outer shaft 6 to which the lifting arms 25 are connected. The rock shaft 57 is slidably held in the guide member i S3 through which the front end of the rod ί 3 ί passes, as shown in Fig. 13. The rear end of the rod 101 is connected to a crank arm 194 arranged in

2,683,545 an upright position on the shaft !04^a, which is suitably journaled in body hinge. The rod 10 2 and the arm 184 are movable rearwardly from the position illustrated in Fig. 13 of the drawings. Adjacent the arm !S4 and carried by the shaft !64^a is an adjustable abutment screw ί ί 5 which is contacted by one of the lifting arms 25 when the gate reaches the raised horizontal position shown in Fig. 7. The shaft i 84^a is rotated counterclockwise upon the lifting arm striking the screw 115. This causes forward movement of the rod (GI beyond the position illustrated in Fig. 13 for enabling the coil spring 100 to bias the arm 67 and the rock shaft 57 in the position illustrated in Fig. 7. The. spring permits rearward movement of the arm 67 and partial rotation of the rock shaft 57 from the position illustrated in Fig. 7 in the operation of the valve 42. The spring 100 and the rod 10! are adapted to yield to the movement of the arm §7 when the handle lever 62 is operated. Adjustment of the abutment screw 115 is made so that it will be engaged and the rod f 01 actuated to shut off the flow of pressure fluid to cylinder 23 whereby the tail-gate is accurately aligned with the floor of the truck when in its raised position as shown in Pig. 7.

The lifting arms 25 are provided at their outer portions adjacent the tail-gate with lugs 73 arranged to be engaged by a pair of pivotally mounted gravity acting catches 80 arranged in the path of the lugs 70. When the lifting arms are swung upwardly to a vertical position they are automatically locked in such position to prevent the tailgate from dropping should there by any release or failure of the hydraulic means. When the tail-gate is swung upwardly from its elevated horizontal position flush with the floor of the truck body to its vertical closed position it is automatically locked in such closed position by a pair of catches 8! located at opposite sides of the truck body exteriorly of the sides thereof and extending through guides 82 and arranged to engage shouldered lugs 83 located at the opposite side edges of the tail-gate at the upper portions of the sides 38 of the frame of the tail-gate. This assures positive support for the gate when dumping. The catches are pivoted at their inner ends 84 to operating levers 85 at points intermediate of the ends thereof. The operating levers 85 are pivoted at the inner ends to the truck body exteriorly of the sides thereof and their outer portions form handles for manually operating the catches 81.

Also when the tail-gate is swung upwardly to the vertical position, the forward flange 80^b comes to rest on flange of angle bracket 80^a to prevent lowering tail-gate in vertical position.

Rock shaft 53 is provided with a pair of oppositely extending arms 68 and 69 pivotally connected at 70 and 7( to the upper ends of a pair of operating rods 72 and 73 having their lower end portions slidable in guides 74 and 75 carried by one of the bearing brackets 2 and arranged to be engaged by lugs 76 and 77 projecting radially from the outer shaft 6. As the tail-gate approaches its vertical position the lug 7 6 engages the lower end of the operating rod 73 and shifts the rock shaft 53 so as to operate the valve 41 and cut off pressure fluid to prevent further movement of the tail-gate. Also when the valve 4 ί is operated to open the tail-gate from the dotted line position shown in Fig. 7 to the horizontal position, the lug T7 of the outer shaft 6 engages the lower end of the operating rod 72 and operates the valve 41 to prevent further rotary move8 ment of the outer shaft. The operating rods 72 and 73 are provided at their upper ends with sections 78 having a threaded connection with the rods for adjusting the same for enabling the valve 41 to be accurately operated.

The dump port-gate IS is held in its closed position by one or more arms 86 of a rock shaft 87 journaled in suitable bearings of the transverse connecting portion of the frame of the tail-gate and provided adjacent to one side thereof with an interiorly arranged radially projecting plate 88 fixed to the rock shaft 87. The dump port engaging arm S3 is movable inwardly and outwardly through a slot 80 in the transverse connecting portion of the frame of the tail-gate to engage it with and disengage it from the dump port-gate and the arm 86 is locked in engagement with the dump port-gate by means of a locking member 93 consisting of a rod slidably mounted in the frame of the tail-gate and provided with an approximately L-shaped arm 9 ί having its terminal portion or bill 92 extending into the frame of the tail-gate and arranged to engage an opening 93 in the plate 88 of the rock shaft 87. The Lshaped arm Si provides an exteriorly arranged loop forming a handle or grip adapted to be readily grasped by the operator for withdrawing the terminal engaging portion 92 from the opening 93 in the plate 88 of the rock shaft 87. When the terminal portion 92 of the locking member is engaged with the opening 93, the rock shaft 87 is held against rotation and the arm 8S is maintained in engagement with the dump port-gate. The locking member 90 is urged inwardly by a coil spring 94 which maintains the terminal portion 92 in engagement with the plate 88 of the rock shaft 87. The coil spring is interposed between a portion of the frame of the tail-gate and the collar 95 or other abutment provided on the inner end of the rod portion of the locking member S3.

The rock shaft 87 is provided at one end adjacent the locking member 90 with an exteriorly arranged arm. 96 which is connected by a link 97 with an angle lever 98 pivotally mounted at 99 on the frame of the tail-gate. The outer portion of the angle lever forms a handle and the angle lever through its link connection with the arm 96 of the rock shaft 87 is adapted to partially rotate the rock shaft to carry the locking arm 86 to and from its position in engagement with the dump port of the tail-gate.

Details of “kick-out valve control mechanism and operation

The control mechanism for the valves 4! and 42 includes a so-called “kick-out” lever release means, as illustrated in Figs. 16 and 17. This mechanism is operatively connected at one end of the valve assembly to a rod which controls the setting of the valve ports, and is illustrated in Fig. 16 in connection with the operation of valve 42. It will be understood that valve 41 is equipped with a similar kick-out control mechanism as for valve 42 and operates in the same manner. The mechanism as illustrated in Fig. 16, comprises an elongated tubular housing (28 having a central bore !2I extending lengthwise therethrough and arranged to slidably receive a shaft (22. The shaft (22 extends outwardly from the housing (20 and is attached at its outer end through an arm (24 to the opposite end of the valve shifting rod 59, as shown at (26. The shaft (22 comprises a reduced diameter portion (23 which extends through an enlarged diameter spring chamber

2,6.83,545

136. A coil spring 133 surrounds the reduced diameter shaft portion i 23 and is retained under compression between the washers 132 and 133. The washers are slidably fitted in the chamber 1.30 and are adapted to be moved axially of the i shaft to compress the spring (31 upon shifting cf the shaft (1(2.

On the outer end of the reduced diameter portion 123 of the shaft a sleeve ! 38 is mounted and which is adapted to slide in the bushing 13.8 .1· which is secured in the end portion of the spring chamber (SO. A stub bolt 140 is received on the outer end of the shaft and is threaded down against a washer 141 whereby the sleeve 136 is retained in place on the shaft between the wash- .1 ers (33 and 141.

On the enlarged diameter portion of the shaft 122 there is provided spaced circumferential grooves (45, (46 and 147 which are adapted to receive a spring-pressed ball detent (58. The a spaced grooves or indentations for receiving the ball 150 cooperate with the setting of the valve rod ! 2 6 so that the valve positions correspond to the spaced groove sections on the shaft (22. The ball detent mechanism comprises a tubular g casting (52 which is threaded into the body of the housing S20 and adapted to contain a coil spring (¢4 for varying the load on the ball (53. The lower end of the spring 154 rests.on the ball detent 150, the ball being of a diameter to fit g snugly into the annular grooves (45, (46, (47. To provide for adjusting the spring load on the ball detent 150, the upper end of the casing (52 is threaded to receive a hollow set screw member i 58 which may be threaded downwardly to vary g· the load on the coil spring (54. The upper end of the casing 8 S3 of the ball detent mechanism is suitably closed by a cap i 60 which is threaded _;on the end of the casing, as illustrated in Fig. IS. A grease cup i 8! is suitably mounted on the cap 169 for conveniently applying lubrication to the ball detent (58.

The valve kick-out lever release assembly is suitably supported on the spaced leg members sSS which in turn are welded to the lower portion of the casing i28. The leg supports 166 are adapted to rest on a base plate (63 suitably mounted on the top of the valve assembly 42, as illustrated in Figs. 16 and 17.

The setting of the rod (26, which is operatively connected to the rod SO and forms an extension thereof, is yieldably maintained in either one of three positions by the adjustable spring loaded ball detent 158. Thus when the valve rod 58 and its counterpart (26 are shifted as by manually moving the lever 62, so as to slide the valve rod, for instance, to the left, as seen in Figs. 13 and 16, the arm (24 attached to the end of the rod (26 carries the shaft (22 to the left so that the ball detent (58 is forced out of its center groove position, representing the neutral or fluid lock position, and upon further movement of the shaft (22, drops into the annular groove ί 47, where the parts are maintained during the operation of the hydraulic lift. The spring 154 of the ball detent is adjustably loaded, as aforementioned, by turning down the screw member (53 so that the spring load on the ball detent is just sufficient to overcome the force exerted by the compression spring (3( and which tends to return the shaft (22 to its center or fluid lock, safety position. Under this action of the spring loaded ball detent, it is unnecessary for the operator to hold his hand on the control lever for operating the hydraulic valves after the lever is moved either to the right or left, to start the desired power' movment of the tail-gate mechanism.

At the end of the particular cycle of operation initiated by movement of the lever 62 or 54, the &gt; valve control rod to which the hand lever is operatively connected is manually shifted or mechanically engaged so that the ball detent (53 is forced out of its seat in the groove and the spring 138 is then permitted to return the 0 shaft (22 to its normal center groove which represents the fluid lock, safety position. In this position all movement of the parts is stopped instantly and maintained in their relative positions. This kick-out mechanism thus provides 5 Anger-tip control so that the tail-gate can be stopped instantly and at any intermediate position desired.

A coil spring IGO mounted on a rod 101 and interposed between a collar 102 on the rod and 0 an arm member 67 of the rock shaft 57 permits lost motion between the parts whereby the manually operated control lever 62 can remain -in a set position until manually moved or its connecting control rod mechanism shifted auto5 matically by engagement therewith of a portion of the tail-gate mechanism being moved to thereby cause the shaft 122 to shift and release the ball detent from the operative position whereby the same is shifted by the coil spring q (31 to its neutral, fluid lock, safety position and all movement of the parts ceases. The same action takes place upon actuation of the control lever 54 which is also provided -with a similar spring actuated ball detent kick-out lever release 5 mechanism and as shown in Fig. 14 by the prime reference characters and corresponding to the reference characters designating the described parts for operating the valve 42.

The catches 39 which are located at opposite 0 sides of the frame of the truck body, are mounted on short shafts iOS journaled in suitable bearings of brackets 109 and provided with arms 110 which are connected by short links 111 to arms 1(2 of a transverse rock shaft 113 which is con₅ nected by a link rod I (4 with the arm 67 of the rock shaft 57 whereby the catches 80 will be lifted out of engagement with the lugs 79 by operation of the lever-62.

While the preferred embodiment of the inven_a tion has been shown and described, it is to be understood that this embodiment may be modified as to the details within the spirit and scope of the invention and as covered by the appended claims.