JPS60249B2 - dump truck - Google Patents

Description

[Detailed description of the invention] The present invention relates to improvements in dump trucks.

The load-carrying capacity of a typical dump truck requires that the overall length of the platform body be maintained at a length that allows it to be lifted to unload the vehicle without destabilizing the vehicle when the platform body is in the lifted position. is limited by the fact that

It is for this reason that so many dump trucks in use today are much shorter and have bed bodies than many other road transport vehicles. Various attempts have been made to overcome this difficulty, and one proposal is US Pat.
Included in No. 361477. This patent discloses a structure in which two carrier bodies are mounted on one frame. The two carrier bodies are separate and partitioned bodies, each defining a separate and partitioned load carrying compartment. Both compartments can be opened by lifting their front ends in order to unload cargo from the rear end.
The cargo is unloaded. To unload the cargo, the rear compartment is raised and then lowered, the front compartment is inserted into the rear compartment, and the coupled assembly is moved to unload the front compartment. be lifted up.
When this construction is used, the front and rear cargo bodies are separated and partitioned from each other so that the rear compartment can be tilted independently from the front compartment. The front compartment is also spaced a considerable distance forward of the rear compartment to move the rear compartment into its raised position. For this purpose, when a vehicle is prepared to transport cargo,
A considerable distance must be provided between the front compartment and the rear compartment. However, the spacing between these compartments is wasted space as far as packaged goods are concerned, so that the entire length of the vehicle is not loaded to its capacity. A removable loading platform for trucks has been proposed for some time.

However, despite the fact that dump truck bodies have been manufactured for many years, there have been no commercially acceptable vehicles that utilize removable bed bodies. A dump truck using a removable platform body is described in US Pat. No. 2,663,343.

In this construction, the carrier body consists of a number of short lengths that are inserted one into the other. The front part has a front wall that slopes backwards and downwards, so that it can be completely emptied when inserted into the rearmost part. This construction is extremely complex and requires each part to be inserted one into the other in sequence, so that the front part is inserted into the third part before the second part is inserted into the third part. It must be fully inserted into the second part. This requires a sophisticated longitudinal drive mechanism.
Phelps has shown that this structure is necessary in order to effectively move the load through a plug-in action. While removable bed bodies have not gained wide capacity, and the truck manufacturing industry has accepted dump trucks despite limitations in load-carrying capacity, bed body structures have been developed. .

The structure, considered as a whole, has a carrier body, which body can be lifted for the purpose of unloading, and a sanitary compartment having an overall length considerably longer than that which could normally be lifted for the purpose of unloading. Sometimes it has only two parts, one of which can be inserted into the other to a stable length. Difficulties associated with lack of stability when unloading long carrier bodies are eliminated by the fact that the entire length of the body can be inserted to a length that allows it to be easily and safely lifted for unloading. It was done. The stability of the carrier body of the present invention is achieved by forming the front part of the body with a larger length than the rear part, so that when the front part is inserted into the rear part, a part of the front part is moved from the rear to the rear. It can be further improved by making it protrude.

This rearwardly projecting portion is placed below the rear end of the rear part when the carrier body is in the raised unloading position. By placing a part of the front part of the carrier body below the rear end of the rear part, the weight of the carrier body, which can be freely inserted and removed, and the extended length of the carrier body can be made such that the front and rear parts are approximately equal in length. Despite the fact that it is sometimes longer than the effective length, it comes downwards. According to one aspect of the present invention, in a dump truck having a longitudinally extending support frame, the common loading compartment has a front section and a rear section inserted from one side into the other side, and is formed inwardly of the front section and the rear section. having a carrier body with a chamber, the front section being mounted for longitudinal movement relative to the frame and the rear section, such that the front section has a common compartment from the rear section substantially larger than either of the sections; and a second position in which the front part is inserted against the rear part to a length that allows the front part to tilt stably, the rear part being in a lowered position for transporting cargo. It is pivotably attached to the front frame so as to be movable between the raised position for unloading the cargo, and is further coupled with the front part to move the front part between the first position and the second position. a first drive device for moving the frame in the longitudinal direction, thereby partially ejecting the cargo contained in the common loading compartment rearwardly from the rear in response to movement toward said second position in use; and a second drive unit cooperating with the rear part and moving the rear part from the lowered position to the raised position to complete unloading from a common loading platform by an ejecting action. Ru.

Embodiments of the present invention will be described below with reference to the drawings.

Referring in more detail to the drawings, the reference numeral 10 generally refers to a dump truck according to an embodiment of the invention.

The dump truck has a frame 12 extending in the longitudinal direction, and a carrier body 14 is attached to the frame 12. The carrier body 14 has a front portion 16 and a rear portion 18. The front part 16 is adapted to slide freely into and out of the rear part 18, and is driven reciprocally with respect to the frame 12 by a hydraulic drive unit 20. The rear portion 18 is mounted on the shaft 2 for pivoting relative to the frame 12.
Can be installed on top of 2. One end of the reciprocating hydraulic drive unit 20 is mounted on the shaft 22 and the pond end is attached to the front 16' by a bracket 24. As shown in FIG. 3, the second hydraulic drive unit 26 has one end attached to a support structure 28 attached to the frame 12 and a pond end pivotably attached to a pivot pin 30; The three pivot pins are held on the underside of the rear portion 18 of the carrier body. This mechanism is a common hydraulic tilting mechanism used to lift the front end of a dump truck body. As shown in FIG. 4, the front portion 16 of the carrier body is
a bottom wall 32; a pair of opposing side walls 34;
It has a front wall 36.

The rear portion 18 includes a pair of opposing side walls 38;
It has a rear plate 40 and a bottom wall 42. The rear plate 40 is conventional in use on dump trucks and is adapted to be removably mounted in the closed position shown in FIG. 1 and in the closed position shown in FIGS. It has a detachable mark that allows it to be moved to the open position. As shown in FIG. 4, the rear end of the front section 16 is open and the front end of the rear section 18 is open, so that a conventional cargo compartment is thereby formed. In all positions of the front relative to the rear, the front is at least partially inserted into the rear, and the front is required to close the rear end of the front and the front end of the rear. Because of this, it can never be fully retracted from the rear. If the rear end of the front section is closed by an end lid wall, the L It involves considerable difficulty. During use, when the carrier body is in the expanded state shown in Figure 1,
The platform body is filled with cargo that can be carried by the dump truck, and at that position the capacity of the platform body reaches its maximum.

In this structure, a carrier body using almost the entire length of the support frame is used. The load may be placed over the entire length of the frame.
To eject the load, the rear plate 40 is released and the hydraulic drive unit 20 is actuated so that the front part is inserted into the rear part and thereby some of the load is removed as shown in FIG. It is lowered from the rear end as shown. The front section 16 is pulled out toward the rear inward to the extent that the combined length of the front section and the rear section is not longer than the permissible length of the cargo bed body of an ordinary dump truck. When the carrier has been effectively shortened by insertion as described above, the hydraulic drive cylinder 26 is actuated to lift the front end of the inserted carrier body and the remainder of the load is lowered in the normal evacuation manner. After the discharge is completed, the carrier body is lowered to a horizontal position. After the carrier body is lowered into a horizontal position, the vehicle is driven forward at normal road speed,
Meanwhile, the carrier body can be expanded by operating the drive mechanism 20. Due to the fact that the carrier body has been lowered into a horizontal position, there is no loss of stability due to unfolding the carrier body while the vehicle is in motion. Although the foregoing description of the preferred embodiment of the present invention does not include a detailed description of all the elements necessary to attach the bed body, these details are well known in the art and are suitable for use with conventional dump trucks. Applied to trucks.

The hydraulic drive unit 20 used for inserting and removing the carrier body is pivoted around an axis 22, and the rear carrier body 18 is pivoted around the axis to move this drive unit to the contracted carrier body shown in FIG. Have it lifted together with the main body.

Various modifications will be apparent to those skilled in the art that do not depart from the scope of the invention.

For example, as shown in FIG. 5, a portion plate 5 may be positioned anywhere along the length of the front portion 16 to separate two separate loads from each other within the carrier body. Ru.
This is also common practice in the field.
Referring to FIG. 6, the reference numeral 52 generally designates the dump truck trailer body, in which like numbers are used for like parts as shown in FIGS. 1-5. In this embodiment, the front section 16 of the carrier body is connected to the rear section 18.
It is sufficiently longer so that a corresponding portion 16a of the front part 16 projects rearwardly from the rear part 18 when the carrier body is inserted into the position shown in FIG. Portion 16a is preferably at least 10% of the total length of rear portion 18. When the carrier body is in the position shown in FIG. 7, the portion 16a is lower than the center of gravity of the carrier body illustrated in FIG.
As a result, the center of gravity of the carrier body illustrated in FIG. 7 is lower than that illustrated in FIG. 3. Lowering the center of gravity of the dump truck bed body when in the raised position serves to increase the stability of the bed body and reduces the concern that the body will roll over during an ejection operation. Extending the front section 16 serves to increase the load carrying capacity of the carrier body, and this increased capacity is obtained without increasing the weight D of the carrier body as a whole. Another insertion/extraction drive mechanism is illustrated in FIGS. 8 and 9.

As shown in Fig. 8 and Fig. 9, the toothed rack 6,
It is attached to the lower side of the front part 16 of the carrier body. The rack has a pair of longitudinally extending rails 62 with a plurality of transverse tooth members 64 equally spaced along its length. The rear hydraulic cylinder 66 is attached to the frame 12 and has a reciprocating piston rod 6 projecting outwardly from one end thereof.
It has 8. The pawl mechanism 701 is attached to the outer end of the piston rod 68 and has a frame 72 in which a pawl 74 is mounted.
is pivotally attached to the transverse pivot pin 76. Claw 74
has an arm 78 projecting downwardly therefrom. Arm 78 is attached to a reciprocating shaft 80 of a double acting pneumatic cylinder 82 . Centering springs 84 and 86 serve to center the arm on axis 80. The pawl 74 has opposing pressing surfaces 88 and 90. The air cylinder 82 is
The pawl 74 is actuated to move the pawl 74 between the positions shown in solid and dotted lines in FIG. 8 and selectively engages the tooth 64.
The rack 60 is moved in the vertical direction in accordance with the movement of the piston rod 68 of the double-acting hydraulic cylinder 66. In use, when carrier body 16 is required to be moved in the direction of arrow A, air cylinder 82 is actuated to place pawl 74 in the position shown in solid line in FIG. Double acting hydraulic cylinder 6
6 is then actuated to move pawl assembly 70 back and forth to engage successive teeth 64. Spring 86 is compressed when pawl 74 is pulled rearwardly past the next tooth 64 and thereafter serves to return pawl 74 to its original engaged position. The stroke length of the hydraulic cylinder 66 is at least 64 teeth.
is equal to the pitch of It is clear that the ratchet drive mechanism described above provides for intermittent movement of the front section 16 relative to the rear section 18.

In order to provide sufficient continuous movement, two drive units are provided as shown in FIG. In this embodiment, pawl assemblies 70a and 70b are of the same construction as described above with respect to FIGS. 8 and 9. Hydraulic cylinders 66a and 66b are interconnected by conduit 92 so that movement of piston rod 68a is synchronous with movement of piston rod 68b with pawl assemblies 70a and 70b offset 180 degrees from each other. be done. This mechanism has claw 7
When 0b moves in the direction of arrow D, it causes a movement of pawl 70a in the direction of arrow C, and vice versa.
This mechanism causes the pawl carried by pawl assembly 70a to move the carrier body in the direction of arrow C as the pawl that slides assembly 70b' is advanced in the direction of arrow D to a position where it engages the next tooth 64. Push out. When pawl assembly 70a is fully extended and begins to move back in the opposite direction of arrow C, pawl 70b
It is fully retracted to begin elongation in the opposite direction of arrow D. The pitch of the teeth 64 and the stroke length of the rear hydraulic cylinder are such that sufficient continuous movement between the rack 60 and the carrier body 16 is achieved. From what has been said above, it is clear that the drive mechanism is such that it is not necessary to provide a very long hydraulic cylinder.

Hydraulic cylinders with very long extensions are expensive to manufacture and fragile to use. The double acting hydraulic cylinder of the present invention has a stroke length in units of approximately 60 to 120 arcs (approximately 2 to 4 feet). Such a cylinder is required for moving a removable carrier body over a length of approximately 15 feet as required in the embodiment of the invention illustrated in FIG. It is considerably cheaper. Furthermore, the drive mechanism 20 of the present invention
is replaced by a drive mechanism similar to that described in Pitt U.S. Pat. No. 3,361,477.

This pit mechanism is permanently mounted on the support frame and is not lifted by the platform body during unloading operations. It is advantageous to have the front part removable into the rear part, since this simplifies the arrangement of the operating mechanism, but it is also possible to make the rear part removable into the front part.

In addition, although the vertically removable drive mechanism is shown as having one end connected to the frame and the other end connected to the front part, it is shown that the drive mechanism has a rack and pinion drive mechanism. It is also possible to have a mechanism in which the rack is carried by the front and the gear pinion is carried either by the rear or by the frame. These and other modifications will be apparent to those skilled in the art. A bed body constructed in accordance with the present invention has an overall length of approximately 40 feet, which is far greater than the length of a dump truck bed body of the type that must be lifted over its entire length to be unloaded. Over.

From the foregoing, the present invention provides a simple and effective structure for increasing the load-carrying capacity of a vehicle of the dump truck type, while also improving the characteristics of a dump truck that allows for complete evacuation of the load from the carrier body. It is clear that it holds.

These and other advantages of the invention will be apparent to those skilled in the art. A still further advantage of the drive mechanism of embodiments in conjunction with the present invention is that the double-acting hydraulic cylinder is able to move the frame and front of the carrier body in order to extend the cylinder and push the front towards the retracted position. It consists in the fact that it can be attached to.

This is in contrast to the double-acting hydraulic cylinder of the embodiment illustrated in FIG. 1, in which the cylinder must be shortened to move the front section to the shortened position. The efficiency of a double-acting hydraulic cylinder is greater when the pressure is applied to the surface of the extended piston than when the pressure is applied to the shortened piston.
This is because the area of the shortened piston is reduced by the diameter of the piston rod. Therefore, the double-acting hydraulic cylinder required for the mechanism of FIG.
It is lighter than that required for the embodiment illustrated in the figures.
These and other advantages will be apparent to those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is a side view of a dump truck according to an embodiment of the present invention, FIG. 2 is a fragmentary side view of the dump truck body showing the first stage of cargo discharge, and FIG. A fragmentary side view similar to Figure 2 showing the next stage; Figures 4 and 5 are plan views of the loading platform; Figure 6 is a side view of a dump truck trailer where the front part of the body is longer than the rear. figure,
Figure 7 is a side view similar to Figure 6 showing the loading platform body in the inserted and ejected position, Figure 8 is a side view of the drive mechanism for inserting the loading platform body, and Figure 9 is the same as Figure 8. A top view of a drive mechanism, and FIG. 10 is a top view of a drive mechanism according to yet another embodiment of the invention. 10... Dump truck, 14... Loading platform body,
12... Frame, 16... Front, 18...
... Rear part, 20, 26 ... Water pressure drive unit, 32, 42 ... Bottom wall, 36 ... Front wall, 38 ... Side wall, 40... Rear plate, 50
・・・・・・Measure board. FIG. l FIG2 FIG. 4 FIG. 5 FIG. 3 FIG. 6 FIG. 8 FIG. 9 FIGIO

Claims (1)

[Scope of Claims] 1. A dump truck having a support frame extending in the vertical direction, which has a loading platform body having a front part and a rear part that can be freely inserted into and removed from each other and each having a common loading compartment compartment formed inside thereof. and the front section is held for longitudinal movement relative to the frame and the rear section, such that the front section extends from the rear section to the common compartment substantially more than either the front section and the rear section. and a second position in which the front portion is inserted to a length that allows the front portion to tilt stably relative to the rear portion, the rear portion being pivotably held in the frame. and is movable between a lowered position for transferring the load and a raised position for discharging the load; driving said front section longitudinally of the frame, thereby ejecting a portion of the cargo contained within said common loading compartment rearwardly from said rear section in response to movement toward said second position in use; a first drive device adapted to cooperate with the rear section to move the rear section from the lowered position to the raised position to complete ejection of cargo from the common cargo compartment; A dump truck characterized in that it has two drive devices. 2. The dump truck according to claim 1, wherein the front section is configured to divide the common compartment into two sub-compartments so that the two loads are separated from each other during transport. A dump truck characterized in that it includes an attached dosing plate. 3. In the dump truck according to claim 1, the loading platform body is configured such that when the front and rear parts are placed in the second position, a portion of the front part protrudes rearward from the front part. A dump truck characterized in that the front part is longer than the rear part, so that the center of gravity of both insertable and removable parts is lower than the center of gravity of the rear part when both the insertable and removable parts are lifted to discharge cargo. 4. In the dump truck according to claim 1, the first drive device includes a plurality of drive devices attached to the front part of the loading platform body, extending in the longitudinal direction thereof, and spaced apart in the longitudinal direction thereon. a rack having teeth; a pawl disposed in close proximity to said toothed rack and adapted to engage said tooth for selectively moving said track back and forth in its longitudinal direction; a reciprocating drive mounted on the track and engaging the pawl to drive the pawl back and forth, the reciprocating drive having a travel length substantially less than the full travel of the front section in both directions. a dump truck, thereby providing movement of the front portion between said first and second positions by a plurality of reciprocating movements of a reciprocating drive. 5. In the dump truck according to claim 1, the first drive device is attached to the front portion of the loading platform body, extends in the longitudinal direction thereof, and is disposed thereon at intervals in the longitudinal direction. a rack having a plurality of teeth arranged in close proximity to said toothed rack and drivingly engages said teeth and ratchets along said rack of said rack as required during use; first and second double-acting pawl members, each of which is configured to vertically move the rack in a first direction on its own; a first position for engaging the teeth of the rack for moving the rack in a second direction opposite to the first direction; and a second position for engaging the teeth of the rack for moving the rack in a second direction opposite to the first direction. a device for selectively positioning the pawl members in the longitudinal direction; a first reciprocating drive device and a second reciprocating drive device for drivingly engaging the two double-acting pawl members, and the movement of the first and second reciprocating drive devices is such that they move in mutually opposite directions. Dump truck, characterized in that the dump truck is synchronized so as to provide a substantially continuous movement of the front part with respect to the rear part. 6. A dump truck having a main body support frame extending in the longitudinal direction, which has a loading platform body attached to the frame, and has a bottom wall, a pair of opposing side walls, and a rear plate, the front end of which is open. a rear portion having a bottom wall, a pair of opposing side walls and a front wall, the front portion being open at its rear end, and engaging the front portion in the first extended position; a front drive device adapted to drive the front section in the longitudinal direction of the frame between the second retracted position and thereby cause a portion of the load to be unloaded by the rear plate in use; The rear end is pivotably mounted on the frame at the rear end of the rear part, and the rear part is installed in a lowering position on the frame for transferring a load and releases the load therefrom when the dump truck is in the second position. a swivel device adapted to move between a raised position in which the front end of the rear part is raised in order to thereby comprising an integral carrier enclosure connected by the bottom wall and side walls of the front and rear portions, the front wall of the front portion and the rear plate of the rear portion; longitudinally relative to said rear portion between a first position in which said portions project forward a substantial distance from said rear portion and a second retracted position in which both portions are inserted one into the other to a length approximately equal to the length of said rear portion; A dump truck characterized by being held so as to move in a direction. 7. In the dump truck according to claim 6, the front part of the loading platform body is arranged such that when the front part and the rear part are placed in the second position, a part of the front part projects rearward from the rear part. A dump truck characterized in that the part is longer than the rear part, so that the center of gravity of both insertable and removable parts is lower than the center of gravity of the rear part when both the insertable and removable parts are lifted to discharge cargo.