JP2000108757A - Lorry - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a load from being applied to a lifting means for a lift frame as much as possible, when a cargo mounting body is loaded and unloaded. SOLUTION: Arranged is a lift frame 2 of which a front end side is supported freely elevatably on a body frame by a lift cylinder 4, and of which a rear end side is supported by a guide roller 6 to be freely slidable in a longitudinal direction by a guide roller 6. A cargo mounting body 47 is arranged freely slidably on the lift frame 2. The fact that a gravity center C position of a cargo including the body 47 reaches to a position in the vicinity of a rear side of the guide roller 6 is detected by a limit switch LS3, to lift-drive thereafter the lift frame 2 using a lift cylinder 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a truck having a slidably supporting body for loading a cargo and reducing the load on lifting means for a lift frame which can be tilted.

[0002]

2. Description of the Related Art Generally, as a vehicle that facilitates the loading and unloading of various types of cargo, including vehicles to be transported, a body on which the cargo is to be loaded is placed horizontally at substantially the same height as the ground, and the cargo is loaded in this state. After that, a truck is known in which the entire body is pulled up (see JP-A-3-27938, JP-A-4-166435, JP-A-4-218440, etc.). In this truck, the body is slidably mounted on a lift frame that is tiltable by lifting means around a fulcrum member at the rear end of the body frame, and the body is tilted with the lift frame tilted. Is slid forward and backward by a slide motor and a chain to load and unload the body.

When the lift frame is tilted for loading and unloading the body in the truck, the position of the center of gravity of the cargo including the body is not particularly considered. That is, in the lowering operation of the body, the lift frame is first tilted backward, and then the body is slid backward. Further, in the loading operation of the body, the body is completely pulled up to the lift frame inclined backward, and then the lift frame is returned to the retracted state.

[0004]

However, if the lift frame is raised without sliding the body,
Basically, lift frame lift and body slide 2
Although loading and unloading can be performed by operation, a large load acts on the lifting means because the center of gravity of the cargo including the body is located farthest from the fulcrum member of the lift frame (the front side of the truck). For this reason, a high-output lift cylinder or the like has been required as a lifting means.

SUMMARY OF THE INVENTION It is an object of the present invention to reduce the load on the lifting means of the lifting frame by reducing the load on the lifting means of the lift frame when loading and unloading the body.

[0006]

In order to solve the above-mentioned problems, a truck according to the present invention has a front end side supported by lifting means provided between a body frame and a lifting end means, and a rear end side having a rear end side. A lift frame supported by a fulcrum member provided on the vehicle body frame, an engaging member provided reciprocally in the front-rear direction along the lift frame, and the lift frame pulled by the engaging member A cargo-loading body capable of climbing upward, a sensor for detecting that the center of gravity of the cargo including the body has reached a predetermined position close to the fulcrum member, and the lifting means based on a signal from the sensor. Control means for driving.

In the truck constructed as described above, the lift frame is driven up and down while the center of gravity of the cargo including the body is close to the fulcrum member, so that the load on the lifting means is reduced. The lift frame can be raised and lowered even with a small output lift cylinder. The “predetermined position near the fulcrum member” is preferably a predetermined position immediately after the fulcrum member has been passed. Thus, the weight of the lift frame and the weight of the cargo including the body are balanced, and the lift frame can be driven up and down with as low a load as possible.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 (A) to 1 (F),
A lorry 1 according to the present invention has a tiltable lift frame 2 on which a body 47 can be mounted. The lift frame 2 has a front end vertically moved by a conventionally known lifting device. The lifting device includes, for example, a hydraulic lift cylinder 4 pivotally supported by a body frame 3 and a lift cylinder 4. The swing arm 5, which is also pivotally supported by the body frame 3 on the rear side, has an intermediate portion pin-connected to the tip of the piston rod of the lift cylinder 4 and a tip portion pin-connected to the lift frame 2. It consists of. A guide roller 6 as a fulcrum member is disposed at the rearmost end of the body frame 3, and the lower surface of the rear end side of the lift frame 2 is slidably supported by the guide roller 6.

The lift frame 2 is shown in detail in FIG.
As shown in FIG. 2B, there are two parallel rails 8 in which U-shaped cross sections are opposed to each other and interconnected by a plurality of connecting members 7, and the front and rear ends of the rails 8 are rails. Sprockets 9, 10 are arranged between the gaps between the parts 8. An endless chain 11 stretched between the sprockets 9 and 10 is driven by a slide motor 9A that drives the front sprocket 9. A slide hook (not shown) as an engaging member is attached to the endless chain 11, and the front end of the body 47 can be detachably engaged with the slide hook.

A projecting member 13 having a downward guide surface 12 supported by the above-described guide roller 6 is fixed to the left and right sides on the rear side of the lift frame 2 over a predetermined length. A body 4 is formed at the rearmost end of the projecting member 13 so as to protrude horizontally in the left-right direction of the lift frame 2.
7 is provided with a ground roller which also serves as a support. The above-mentioned lift cylinder 4 and slide motor 9A are automatically controlled by control means provided in the driver's seat, and this control means is functionally represented by the flowchart of FIG. Some conditional branches in this flowchart are processed by signals from the limit switches LS1 to LS5 in FIG.

The lorry is constructed as described above, and the loading and unloading operation of the body 47 or the cargo by this lorry is
This will be described with reference to the flowcharts of FIGS. Here, in FIGS. 1A to 1F, a black circle (●) indicates a body 47.
Or the center of gravity C of the cargo, and steps S1 to S23 in FIG. 3 indicate the following contents. S1: Main switch operation S2: Is the "Down" push button pressed? S3: Is the limit switch LS2 detected? S4: Slide motor down S5 ... Is limit switch LS3 detected? S6: Slide motor stop, lift Cylinder 4 extension S7: Is the limit switch LS4 detected? S8: Lift cylinder 4 stopped, slide motor lowered S9: Is the limit switch LS5 detected? S10: Slide motor stopped, lift cylinder 4 extended S11: Container unloading completed S12 ... S13: Limit switch LS5 is detected S14: Lift cylinder 4 contraction S15: Limit switch LS4 is detected S16: Lift cylinder 4 stops, slide motor is raised S17 ... Remi S18 ... Slide motor stop, lift cylinder 4 contraction S19 ... Limit switch LS2 is detected S20 ... Lift cylinder 4 stop, slide motor up S21 ... Limit switch LS1 is detected S22 ... Illumination of the runnable lamp S23. Loading of the container is completed. FIG. 1A shows a state in which a body 47 on which cargo such as a transported vehicle is previously loaded is already loaded on the truck 1. The operation will be described from the lowering operation.
When the main switch for loading / unloading the body 47 provided in the driver's seat is turned on, the control flow from step S1 is started. In the driver's seat, two types of push buttons of "unload" and "load" of the body 47 are disposed adjacent to the main switch, and it is determined in step S2 and step S12 which push button is pressed. Is determined. "Unload"
Is pressed, after confirming that the lift frame 2 is in the retracted state in step S3, the endless chain 11 is driven by the slide motor 9A in a direction to retract the slide hook, and the body 47 is moved by the slide hook. The slide frame 2 is slid toward the rear end of the lift frame 2. At this time, the lift frame 2 maintains a horizontal state while the lift cylinder 4 is stopped. Whether the lift frame 2 is horizontal or not is determined by a limit switch L disposed between the body frame 3 and the lift frame 2.
The determination is made based on the signal from S2.

With the horizontal movement of the body 47, the retraction movement of the body 47 is temporarily stopped when the center of gravity C has passed over the guide roller 6 (FIG. 1B), and then the lift cylinder 4 is extended to operate the lift frame. 2 is rotated upward. Center of gravity C
Strictly speaking, it is not known whether or not the center of gravity has moved beyond the guide roller 6 unless the actual position of the center of gravity, which is different for each cargo, is measured. The sensor 47 is uniformly located at the center of the body 47 in the front-rear direction and is detected uniformly by a limit switch LS3 as a sensor for detecting a predetermined sliding position of the body 47. As described above, the center of gravity C is
1B, the body 47 is first slid horizontally rearward, so that the weight of the left lift frame 2 and the weight of the cargo including the right body 2 in FIG. The balance is substantially balanced, so that the lift cylinder 4 can be driven with a lower load than in the past.
The swing arm 5 having a smaller allowable load and weight can be adopted.

When the lift frame 2 rotates upward and the lift angle of the lift frame 2 reaches a predetermined size, the lift cylinder 4 is temporarily stopped (FIG. 1 (C)), and then the endless chain 11 is restarted. The body 47 is driven to move further backward (FIGS. 1D and 1E). As a result, the grounding roller 52 at the rear end of the body 47 contacts the ground G, and the body 47 is supported by both the lift frame 2 and the ground G. Whether the lift frame 2 has reached a predetermined lift angle is detected by a limit switch LS4 disposed between the lift frame 2 and the swing arm 5.

As shown in FIG. 1 (E), the drive of the endless chain 11 is stopped when the body 47 has moved backward to the end, and then the lift cylinder 4 is extended again and the lift frame 2 is tilted to the maximum lift angle. (FIG. 1F).
Whether the body 47 has moved to the end is detected by a limit switch LS5 disposed at the rear end of the lift frame 2. When the lift frame 2 is tilted to the maximum lift angle, the body 47 is separated from the slide hook of the lift frame 2. When the body 47 has been separated, the lift frame 2 is returned to its original horizontal position.

[0015] When loading the body 47, contrary to the above,
By pressing the "loading" push button in the driver's seat, the respective steps from FIG. 1 (F) to FIG. 1 (A) may be performed in order, contrary to the above-described unloading operation. That is, the truck 1 without the body 47 is retracted toward the front end of the body 47 placed horizontally on the ground, and when approaching a predetermined position, the endless chain 11 is driven by the slide motor 9A to move the slide hook to the rearmost end. And lift the lift frame 2 to the maximum angle. Thus, the slide hook is engaged with the body 47, and thereafter, the operations from FIG. 1 (F) to FIG. 1 (A) are sequentially executed.

Referring again to the flow of FIG.
If the "loading" push button is pressed in step S12, it is first determined in step S13 whether or not the slide hook has moved to the rearmost position based on a signal from the limit switch LS5. When it is confirmed that the slide hook has moved to the rearmost position (FIG. 1 (F)),
In step S14, the lift cylinder 4 starts the shortening operation, and when it is confirmed by the signal from the limit switch LS4 that the lift angle has returned to the predetermined lift angle in step S15 (FIG. 1E), the lift cylinder 4 is temporarily stopped in step S16. 4 is stopped, and the endless chain 11 is driven by the slide motor 9A instead. When it is determined from the signal from the limit switch LS3 in step S17 that the slide hook has advanced to the predetermined position (FIG. 1).
(C)), the slide motor 9A is temporarily stopped in step S18, and the lift cylinder 4 starts the shortening operation again instead. The load of the lift cylinder 4 at this time is also the center of gravity C
Is reduced because it is close to the guide roller 6. When it is determined in step S19 that the lift frame 2 has become horizontal based on a signal from the limit switch LS2 (FIG. 1B), the lift cylinder 4 is stopped in step S20, and the slide motor 9A is pulled up instead. Driven. Step S indicates that the slide hook has advanced to the foremost end position by the pulling drive of the slide motor 9A.
When it is determined at 21 by a signal from a limit switch LS1 disposed at the front end of the lift frame 2 (FIG. 1)
(A)), the runnable lamp in the driver's seat is turned on in step S22, and the loading operation is completed in step S23.

The embodiment of the present invention has been described above. However, the present invention is not limited to the above embodiment, and various modifications are possible. For example, in the above embodiment, the center of gravity C is located behind the guide roller 6. The lift cylinder 4 is driven when reaching the vicinity position. However, the center of gravity C does not necessarily need to be a position near the rear of the guide roller 6, and if the position is closer to the guide roller 6 than before, for example, The position near the front of the guide roller 6 may be used, and the load on the lift cylinder 4 can be reduced by an amount approaching the guide roller 6. In the above embodiment, the case where the lift frame 2 is slidably supported by the guide rollers 6 has been described. However, the present invention is applicable to a case where the rear end fixed position of the lift frame 2 is rotatably supported by hinge means. Is applicable. Further, the present invention is applicable regardless of whether the body 47 can be separated from the lift frame 2 or not.

[0018]

As described above, the present invention drives the lift frame up and down while the position of the center of gravity of the cargo including the body is close to the fulcrum member of the lift frame, so that the load on the lifting means can be reduced and the output can be reduced. Inexpensive lifting means can be adopted.

[Brief description of the drawings]

1 (A) to 1 (F) are side views of a truck loading / unloading process.

2A is a plan view of a lift frame, and FIG. 2B is a side view of the lift frame.

FIG. 3 is a flowchart of a body loading / unloading process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lorry 2 Lift frame 3 Body frame 4 Lift cylinder 5 Swing arm 6 Guide roller 11 Endless chain 47 Body

Continuation of the front page (72) Inventor Ken Shima 6-45 Koshienguchi, Nishinomiya-shi, Hyogo Pref.

Claims (2)

[Claims] A lift frame having a front end side supported by lifting means disposed between the vehicle body frame and a lift end, the rear end side supported by a fulcrum member disposed on the vehicle body frame; An engagement member disposed reciprocally in the front-rear direction along the lift frame, a cargo mounting body pulled by the engagement member and able to ride on the lift frame, and a center of gravity of the cargo including the body A lorry comprising: a sensor for detecting that the position has reached a predetermined position close to the fulcrum member; and control means for driving the lifting means based on a signal from the sensor. 2. A lift frame having a front end side supported by lifting means disposed between the vehicle body frame and a lift end supported at a rear end side by a fulcrum member disposed on the vehicle body frame. An engaging member disposed reciprocally in the front-rear direction along the lift frame, a cargo mounting body pulled by the engaging member and capable of riding on the lift frame, and a center of gravity of the cargo including the body A lorry comprising: a sensor for detecting that the position has exceeded the position of the fulcrum member; and control means for driving the lifting means based on a signal from the sensor.