JP7277293B2 - Vertical loading platform lifting device - Google Patents

Description

The present invention relates to a vertical loading platform lifting device, which is a type of loading platform lifting device, and more particularly to a high lift type vertical loading platform lifting device capable of raising the loading platform to a position higher than the floor surface of the loading platform.

One type of loading platform lifting device is a vertical loading platform lifting device that lifts and lowers the loading platform along left and right posts fixed to the loading platform of a vehicle. In the vertical loading platform lifting device, when traveling without using the loading platform, it is arranged along the inner wall or outer wall of the door of the loading platform (including containers), or constitutes a part of the side wall of the loading platform. Store the loading platform vertically. An upright loading platform is generally fixed by hooking a lock handle provided on the loading platform onto a hook provided on a post (Patent Document 1, etc.).

Japanese Unexamined Patent Application Publication No. 2007-203906

Here, in a high-lift type vertical loading platform lifting device that can raise the loading platform to a position higher than the floor of the loading platform, the stopper for stopping the loading platform at the floor position of the loading platform is the hook described above. may be provided. The hook is configured to rotate horizontally, and the stopper rotates integrally with the hook. In general, when the hook is in a posture where the lock handle of the load receiving platform can be hooked, the stopper interferes with the elevating orbit of the load receiving platform (strictly speaking, the sub-post or the like that moves up and down together with the load receiving platform). In this case, when the load-receiving platform rises, the sub-post hits the stopper, and the load-receiving platform can be stopped at the floor position of the loading platform. .

However, in order to raise the load receiving platform higher than the floor of the vehicle loading platform in the high-lift type vertical loading platform lifting device, it is necessary to rotate the hook in the horizontal direction to remove the stopper from the elevating orbit of the sub-post. be. If stoppers are provided on both the left and right posts, the two stoppers must be operated by moving to the left and right of the loading platform each time the loading platform is raised above the floor of the loading platform. It will force people to do troublesome work.

In particular, one of the advantages of the device for lifting and lowering the load receiving tray is that the load receiving tray can be lifted and lowered simply by pressing the upper button and the lower button. However, if the worker is forced to switch the stopper by raising or lowering the load receiving table with respect to the floor surface position of the loading table, the advantage of the easy-to-operate load receiving table lifting device is lost.

In addition, in a structure using a stopper, when the sub-post collides with the stopper, a collision noise is generated in no small amount, and since the stopper is only used to physically stop the sub-post from rising, the load-receiving table does not move when the upper button is pressed. Even though there is no drive sound is generated. For example, it is not uncommon to use a loading platform lifting device in a residential area, and from the viewpoint of noise reduction, it is necessary to consider such collision noise and unnecessary driving noise.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vertical load receiving platform lifting device that can omit a stopper for stopping the load receiving platform at the floor position of the loading platform, and that can improve ease of operation and quietness of operation.

In order to achieve the above object, the present invention provides a vertical load-receiving platform lifting device mounted on a loading platform of a vehicle. a load receiving platform that can be raised and lowered, a hydraulic cylinder that drives the load receiving platform up and down, a sensor that detects that the load receiving platform is at a set position, a first operating device and a second operating device that operate the loading platform, a control device having a function of stopping the hydraulic cylinder when the sensor detects that the load receiving tray has reached the set position , wherein the control device raises the load receiving tray by the first operating device. Only when at least one of the raising operation and lowering operation by the first operating device is performed among the operation and lowering operation and the raising operation and lowering operation of the cargo receiving platform by the second operating device reaches the set position, the hydraulic cylinder is stopped .

According to the present invention, it is possible to omit a stopper for stopping the load receiving board at the floor position of the load board, and it is possible to improve the ease of operation and the quietness of the operation.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view of the vertical loading platform lifting device according to the first embodiment of the present invention. 1 is a left side view of a vertical load receiving platform lifting device according to a first embodiment of the present invention; FIG. FIG. 4 is a rear view of the cross member provided in the vertical load receiving platform lifting device according to the first embodiment of the present invention; FIG. 2 is a schematic diagram showing wire paths in the vertical load receiving platform lifting device according to the first embodiment of the present invention. 1 is a circuit diagram of a power unit of a vertical load receiving platform lifting device according to a first embodiment of the present invention; A circuit diagram of a power unit of a vertical loading platform lifting device according to a second embodiment of the present invention.

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

(First embodiment)
－Vertical loading platform lifting device－
FIG. 1 is a perspective view of a vertical load receiving tray lifting device according to a first embodiment of the present invention, FIG. 2 is a left side view, FIG. 3 is a rear view of a cross member to be described later, and FIG. 4 is a schematic diagram showing wire paths. It is a diagram. 2 shows the inside of the post 1L, and FIG. 3 shows the inside of the cross member 5 as seen through. 2 and 3, the wires 8L and 8R are omitted.

In the embodiment described below, a case where a vertical loading platform lifting device 100 (hereinafter abbreviated as the loading platform lifting device 100) is mounted on the rear part of the loading platform LP of the vehicle will be described as an example. In some cases, the loading platform lifting device 100 is mounted on the side of the. Further, in the specification of the present application, the post 1L, 1R side (left side in FIG. 2) with respect to the load receiving platform 4 is the front side of the load receiving platform lifting device 100, and the load receiving platform 4 side (in FIG. 2) is positioned with respect to the post 1L, 1R. ) is the rear of the load receiving platform lifting device 100 . Therefore, when the load-receiving platform lifting device 100 is mounted on the side of the loading platform LP of the vehicle, the front-rear direction of the load-receiving platform lifting device 100 deviates from the front-rear direction of the vehicle by 90 degrees in the horizontal direction.

The loading platform lifting device 100 includes posts 1L, 1R, subposts 2L, 2R, sliders 3L, 3R, loading platform 4, cross member 5, hydraulic cylinders 6, pulleys 7La-7Lc, 7Ra-7Rc, wires 8L, 8R, and a power unit. 9. Each element will be described below.

-post-
The posts 1L and 1R are positioned at both left and right ends of the rear end portion of the loading platform LP of the vehicle and extend vertically. Hollow square pipes, for example, are used for these left and right posts 1L and 1R. The space on the front side inside the posts 1L and 1R is called a front chamber 1a, and the space on the rear side is called a rear chamber 1b. The front chamber 1a and the rear chamber 1b are separated by a partition wall 1c (FIG. 2) except for the upper portion. A vertically extending slit 1d (FIG. 1) is provided in the rear wall of the rear chamber 1b. A stopper 1e (FIG. 2) is provided on the top of the posts 1L and 1R to define the upper limit of the lifting range of the load receiving table 4. As shown in FIG. The stopper 1e is a structure that stops the load receiving table 4 at the upper limit by coming into contact with the sub-posts 2L, 2R or the sliders 3L, 3R, and is housed inside the posts 1L, 1R. Further, the posts 1L and 1R are provided with hooks 1f for holding the load receiving table 4 in an upright retracted posture by engaging a lock handle 4b (described later) provided on the load receiving table 4. As shown in FIG. The hook 1f is a non-movable fixed structure.

-sub post-
The subposts 2L, 2R (only the left subpost 2L is shown in FIG. 2) are vertically movably inserted in the rear chambers 1b of the posts 1L, 1R. Slits (not shown) are vertically formed in the rear walls of the sub-posts 2L and 2R corresponding to the slits 1d of the posts 1L and 1R. These sub-posts 2L and 2R are provided with rollers 2a (FIG. 2) that roll on the rear inner wall of the rear chamber 1b. It is Although not shown, a guide roller is fixed to the lower portion of the rear chamber 1b of the posts 1L and 1R and partially faces the rear chamber 1b. Also guided by rollers.

-Slider-
The sliders 3L, 3R extend vertically, are inserted into the subposts 2L, 2R, respectively, and move vertically inside the subposts 2L, 2R. Rollers 3a (FIG. 2) are provided above and below the sliders 3L and 3R. These rollers 3a roll on the inner walls of the sub-posts 2L and 2R when the sliders 3L and 3R are raised and lowered. The rear portions of the sliders 3L, 3R protrude behind the posts 1L, 1R through slits (not shown) of the subposts 2L, 2R and slits 1d of the posts 1L, 1R. A bracket 3b is provided at the lower portion of the rear portion of the sliders 3L, 3R projecting rearward from the posts 1L, 1R. Further, the sliders 3L and 3R are provided with wire retainers 3c (FIG. 2) for fixing the ends of the wires 8L and 8R so as to be positioned, for example, between the upper and lower rollers 3a.

- Receiving table -
The load receiving platform 4 is rotatably connected to the bracket 3b of the sliders 3L, 3R via a pin 4a (FIG. 2), and is guided by the subposts 2L, 2R and the posts 1L, 1R together with the sliders 3L, 3R. up and down. In particular, the load receiving platform lifting device 100 of this embodiment is of a high lift type, and the lifting range of the load receiving platform 4 exists not only below the floor position but also above the floor position. The “floor surface position” means the height position of the load receiving platform 4 ((B) in FIG. 2) where the load receiving surface (upper surface) matches the height of the floor surface of the loading platform LP and the upper surface of the cross member 5. . The load-receiving platform 4 can be moved up and down across the floor position of the loading platform LP, that is, vertically above and below the floor position. When not in use, the load receiving platform 4 is erected vertically to form a rear wall (tailgate) of the loading platform LP. In the horizontally fallen posture, the load receiving platform 4 moves up and down while loading loads, workers, etc. during cargo handling work. In addition, lock handles 4b (only the left one is shown in FIG. 1) are provided on both left and right sides of the load receiving table 4. As shown in FIG. The load receiving table 4 is moved to a storage position at a predetermined height (in this example, the floor position of the loading platform LP) and erected, and the lock handle 4b is pulled out to the left and right and hooked to the hook 1f, whereby the load receiving table 4 is erected. It is fixed (stored) with respect to the posts 1L and 1R in a posture.

－Cross member－
The cross member 5 extends laterally and connects vertical intermediate portions of the posts 1L and 1R. The cross member 5 is hollow, and its internal space is connected to at least the front chambers 1a of the posts 1L and 1R. When the load receiving platform lifting device 100 is mounted on the vehicle, the cross member 5 is positioned above the chassis frame of the vehicle, and the upper surface of the cross member 5 is flush with the floor surface of the loading platform LP. Although not shown, the rear surface of the cross member 5 is a removable cover. The cross member 5 is also provided with wire retainers 5a and 5b for fixing ends of the wires 8L and 8R, respectively.

－Hydraulic Cylinder－
The hydraulic cylinder 6 is a driving device for driving the load receiving table 4 up and down, and is accommodated in the cross member 5 in a laterally extending posture. The hydraulic cylinder 6 can be installed with the rod facing left, but in this embodiment, the tube is fixed to the inner wall of the cross member 5 via a support member with the rod facing right. . The distal end of the rod of the hydraulic cylinder 6 reciprocates in the horizontal direction inside the cross member 5 as indicated by the arrows in FIG. 3 as the hydraulic cylinder 6 expands and contracts.

-pulley-
The pulleys 7La-7Lc guide the wire 8L, and the pulleys 7Ra-7Rd guide the wire 8R (FIG. 4). These pulleys 7La to 7Lc and pulleys 7Ra to 7Rd preferably have a large diameter within a range that does not interfere with other structures. This is because the curvature of the turning portions of the wires 8L, 8R is suppressed, and the long life of the wires 8L, 8R can be expected.

The pulleys 7La and 7Ra are movable pulleys (these two pulleys are hereinafter appropriately referred to as "moving pulleys"). The movable pulleys 7La and 7Ra are rotatably attached to the ends of the rods of the hydraulic cylinders 6 via brackets with their rotating shafts extended forward and backward, and are stacked in the cross member 5 forward and backward. These movable pulleys 7La and 7Ra reciprocate horizontally in a wide range of the right half inside the cross member 5 as the hydraulic cylinder 6 expands and contracts (FIG. 3). Further, each of the movable pulleys 7La and 7Ra has a plurality of (two rows in this embodiment) wire grooves.

On the other hand, the pulleys 7Lb, 7Lc, 7Rb-7Rd are fixed pulleys (these five pulleys are hereinafter referred to as "fixed pulleys" as appropriate).

Of these, the fixed pulleys 7Lb, 7Rb, and 7Rc are accommodated in the cross member 5 with their rotating shafts extended forward and backward (FIG. 3). The fixed pulleys 7Lb and 7Rb are positioned at the left end of the cross member 5 and attached to the tube of the hydraulic cylinder 6 (or the inner wall surface of the cross member 5) via brackets. These fixed pulleys 7Lb and 7Rb each have a plurality of (two rows in this embodiment) wire grooves, similar to the movable pulleys 7La and 7Ra. These fixed pulleys 7Lb and 7Rb are located on the opposite side (post 1L side) of the moving pulleys 7La and 7Ra across the hydraulic cylinder 6, and partially face the inner space (front chamber 1a) of the post 1L. The fixed pulley 7Rc is located at the right end of the cross member 5, and is attached to the inner wall surface of the cross member 5 via a bracket so that a portion thereof faces the front chamber 1a of the post 1R.

The pulleys 7Lc and 7Rd are positioned above the partition wall 1c inside the posts 1L and 1R, respectively, and arranged across the front chamber 1a and the rear chamber 1b. These pulleys 7Lc and 7Rd are rotatably supported by posts 1L and 1R with their rotating shafts extending left and right.

- Wire -
As shown in FIG. 4, the wire 8L (solid line) is wound around the movable pulley 7La and the fixed pulleys 7Lb and 7Lc, one end is in a fixed relationship with the cross member 5 which is a stationary structure, and the other end is on the left side. It is engaged with the wire retainer 3c of the slider 3L. Specifically, one end of the wire 8L is engaged with the wire retainer 5a and fixed to the cross member 5 via the wire retainer 5a. The wire 8L extends rightward from the wire retainer 5a, is hooked to the wire groove in the rear row of the movable pulley 7La to the left, and is hooked to the wire groove in the rear row to the fixed pulley 7Lb and is folded back to the right. After that, the wire 8L is hooked on the wire groove in the front row of the movable pulley 7La and folded back to the left again, and then hooked on the wire groove in the front row of the fixed pulley 7Lb and turned upward. Furthermore, the wire 8L is hooked on the fixed pulley 7Lc and folded downward, and finally the other end is locked to the wire retainer 3c of the slider 3L.

One wire 8R (broken line) is wound around the movable pulley 7Ra and the fixed pulleys 7Rb-7Rd, and has one end fixed to the cross member 5, which is a stationary structure, and the other end wire retainer 3c of the right slider 3R. locked to. Specifically, one end of the wire 8R is engaged with the wire retainer 5b and fixed to the cross member 5 via the wire retainer 5b. The wire 8R extends rightward from the wire retainer 5b, is hooked to the wire groove in the rear row of the movable pulley 7Ra to turn leftward, and is hooked to the wire groove in the rear row of the fixed pulley 7Rb to turn rightward. After that, the wire 8R is hooked on the wire groove in the front row of the movable pulley 7Ra and directed leftward again, hooked on the wire groove in the front row of the fixed pulley 7Rb and folded back further to the right, and then turned upward via the fixed pulley 7Rc. do. Furthermore, the wire 8R is hooked to the fixed pulley 7Rd and folded downward, and finally the other end is locked to the wire retainer 3c of the slider 3R. The sliders 3L, 3R and the load receiving table 4 are thus suspended by the wires 8L, 8R.

－Power unit－
FIG. 5 is a circuit diagram of the power unit. The power unit 9 is a power device that drives the hydraulic cylinder 6, and is accommodated in a unit box 9a provided on the rear left side of the loading platform LP (front side of the left post 1L) as shown in FIG. The power unit 9 includes an electric motor M, a hydraulic pump P, an oil tank T, switching valves V1 and V2, and a control device 10, as shown in FIG. The hydraulic pump P is driven by an electric motor M, and discharges hydraulic oil sucked from an oil tank T to a pump line PL as pressure oil. The pump line PL branches into hydraulic pipes L1 and L2, and is connected to the hydraulic cylinder 6 via the hydraulic pipe L1 and to the oil tank T via the hydraulic pipe P2. In this embodiment, the hydraulic cylinder 6 is single-acting.

The hydraulic pipe L1 is provided with a switching valve V1 for upward movement, and the switching valve V1 is opened and closed by an electric signal input to the solenoid S1 to open or shut off the hydraulic pipe L1. The switching valve V1 is of a normally closed type that shuts off the hydraulic line L1 when the solenoid S1 is demagnetized.

The hydraulic pipe L2 is provided with a switching valve V2 for lowering operation, and the switching valve V2 is opened and closed by an electric signal input to the solenoid S2 to open or shut off the hydraulic pipe L2. The switching valve V2 is of a normally closed type that shuts off the hydraulic line L2 when the solenoid S2 is demagnetized.

A flow control valve V3 is provided downstream of the switching valve V2 in the hydraulic pipe L2. Further, the pump line PL is provided with a relief valve V4, and the maximum value of the pressure of the pump line PL is regulated by the relief valve V4. A wire E1 connecting the electric motor M and the battery BT is provided with a contact CT2 of a contactor switch.

-Control device-
The control device 10 is a means for controlling the operation of the hydraulic cylinder 6, and the load receiving platform 4 reaches a set position, which is the floor position of the loading platform LP in this embodiment, while the load receiving platform 4 is being lifted (raised in this embodiment). It has a function to stop the hydraulic cylinder 6 when the sensor SN detects that it has been done. Although the control device 10 can be composed of a computer, it is composed of a relay switch CR in this embodiment. A sensor SN is a position sensor for detecting that the load-receiving table 4 is on the floor surface of the load-carrying board LP. A contact-type or non-contact-type position sensor such as a limit switch or a proximity sensor can be used as the sensor SN. For example, it is possible to install the sensor SN on the post 1L or 1R to detect the position of the slider 3L or 3R. The sensor SN detects that the extension amount of the hydraulic cylinder 6 is a predetermined value, and detects that the load receiving tray 4 has reached the floor surface position.

A wiring E2 branches from a wiring E1 that connects the battery BT and the electric motor M, and a power switch SW of the power unit 9 is provided on the wiring E2. The wiring E2 branches into five wirings E3 to E7, and the battery BT is connected to each power supply target via the wirings E3 to E7.

The wires E3 and E4 are appropriately connected to the solenoids S1 and S2 of the switching valves V1 and V2 and the coil CT1 of the contactor switch via the first operating device O1. Specifically, the wiring E3 is connected only to the solenoid S1 and the coil CT1 out of the solenoids S1 and S2 and the coil CT1, and the wiring E4 is connected only to the solenoids S1 and S2 out of the solenoids S1 and S2 and the coil CT1. Connected. The first operating device O1 is for operating the load receiving platform 4 in a lifting range below the floor position of the loading platform LP (hereinafter referred to as "lower area"). installed in a position higher than the floor position of the This first operating device O1 is a simple one that is operated by a push-button type upper button U1 and lower button D1. The up button U1 is provided on the wire E3, and the down button D1 is provided on the wire E4.

The wires E6 and E7 are connected to the solenoids S1 and S2 of the switching valves V1 and V2 and the coil CT1 of the contactor switch via the second operating device O2. Specifically, the wiring E6 is connected only to the solenoid S1 and the coil CT1 out of the solenoids S1 and S2 and the coil CT1, and the wiring E7 is connected only to the solenoids S1 and S2 out of the solenoids S1 and S2 and the coil CT1. Connected. The second operating device O2 is for operating the load receiving platform 4 in a lifting range (hereinafter referred to as "upper region") above the floor position of the loading platform LP. It is installed at a higher position than the first operating device O1. Like the first operating device O1, the second operating device O2 is also simple to operate with the push-button upper button U2 and the lower button D2, and constitutes a parallel circuit with the first operating device O1. The up button U2 is provided on the wire E6, and the down button D2 is provided on the wire E7.

The wire E5 is connected to the coil CR1 of the relay switch CR through the sensor SN. When the load receiving platform 4 is located on the floor of the loading platform LP, the contact of the sensor SN is closed and current flows through the coil CR1. A contact CR2 of the relay switch CR is provided on the wiring E3. The relay switch CR is of a normally closed type in which the coil CR1 is demagnetized and the contact CR2 is closed. When the coil CR1 is energized, the contact CR2 is opened.

-motion-
When using the load-receiving platform lifting device 100, first, the load-receiving platform 4 (A) stored upright as shown in FIG. 4 is knocked down and deployed horizontally (B). Then, the power of the power unit 9 is turned on by the power switch SW.

When lowering the load receiving tray 4 from the floor position to the lower area, the lower button D1 of the first operating device O1 is pressed. While the lower button D1 is being pressed, the solenoids S1 and S2 are energized to open the switching valves V1 and V2, and the weight of the sub-posts 2L and 2R, the sliders 3L and 3R, and the load receiving base 4 causes hydraulic oil to flow out of the hydraulic cylinder 6 into the oil tank T. , the hydraulic cylinder 6 is contracted and the load receiving table 4 is lowered (C). During this time, the electric motor M does not operate because the contact CT2 of the contactor switch remains open. When the operation of the lower button D1 is stopped, the switching valves V1 and V2 are closed to stop the load receiving table 4, and even if the load receiving table 4 contacts an obstacle such as the ground, the load receiving table 4 is stopped.

After that, when the load receiving table 4 is to be lifted in the lower area, the upper button U1 of the first operating device O1 is pressed. While the upper button U1 is pressed, the solenoid S1 and the coil CT1 are energized to operate the electric motor M and the hydraulic pump P, the switching valve V1 opens (the switching valve V2 is closed), and the hydraulic oil supplied from the hydraulic pump P As a result, the hydraulic cylinder 6 is extended and the load receiving table 4 is lifted. When the operation of the upper button U1 is stopped, the electric motor M and the hydraulic pump P are stopped, the switching valves V1 and V2 are closed, and the load tray 4 is stopped. Further, when the load receiving platform 4 rises to the floor surface position of the loading platform LP (B), the contact of the sensor SN is closed and the coil CR1 is energized, the contact CR2 of the relay switch CR is opened and the upper button U1 of the first operating device O1 is activated. and the solenoid S1 are disconnected. That is, even when the first operating device O1 is being operated to raise the load receiving platform 4, when the sensor SN detects that the load receiving platform 4 has risen to the floor surface position of the loading platform LP, the switching valve V1 is closed. Then the receiving table 4 stops. At this time, the connection between the upper button U1 and the coil CT1 is cut off by opening the contact CR2, and the contact CT2 of the contactor switch is opened to stop the hydraulic pump P as well. As long as the receiving table 4 is on the floor, the operation of the upper button U1 is invalid. Here, when the load receiving table 4 is to be stored, the load receiving table 4 is erected and fixed by the lock handle 4b.

When raising the load receiving tray 4 from the floor position to the upper area (D), the up button U2 of the second operating device O2 is pressed. Since there is no contact CR2 of the relay switch CR between the upper button U2, the solenoid S1 and the coil CT1, the lifting operation can be effectively performed even if the load receiving tray 4 is on the floor. While the upper button U2 is pressed, the solenoid S1 and the coil CT1 are energized to operate the electric motor M and the hydraulic pump P, the switching valve V1 opens (the switching valve V2 is closed), and the hydraulic oil supplied from the hydraulic pump P As a result, the hydraulic cylinder 6 is extended and the load receiving table 4 is lifted. When the operation of the upper button U2 is stopped, the electric motor M and the hydraulic pump P are stopped, the switching valves V1 and V2 are closed, and the load tray 4 is stopped. Further, when the receiving table 4 rises to the upper limit, it interferes with the stopper 1e and stops.

When lowering the load receiving table 4 in the upper area, the lower button D2 of the second operating device O2 is pressed. While the lower button D2 is being pressed, the solenoids S1 and S2 are energized to open the switching valves V1 and V2, and the weight of the sub-posts 2L and 2R, the sliders 3L and 3R, and the load receiving base 4 causes hydraulic oil to flow out of the hydraulic cylinder 6 into the oil tank T. , the hydraulic cylinder 6 is contracted and the load receiving table 4 is lowered. During this time, the electric motor M does not operate because the contact CT2 of the contactor switch remains open. When the operation of the lower button D1 is stopped, the switching valves V1 and V2 are closed and the load receiving table 4 is stopped.

-effect-
(1) When the loading platform LP reaches the floor position, the lifting motion of the loading platform 4 is automatically stopped, so a stopper for stopping the loading platform 4 at the floor position of the loading platform LP can be omitted. Since the load receiving platform 4 is not restrained by the stopper at the floor position of the loading platform LP, there is no need to release the stopper when lifting the loading platform 4 from the floor position of the loading platform LP. There is, and the simplicity of operation improves. In addition, there is no collision sound with the stopper when the load receiving platform 4 reaches the floor surface position of the loading platform LP. Furthermore, since the electric motor M and the hydraulic pump P are stopped when the cargo receiving tray 4 reaches the floor surface of the cargo tray LP, the operating noise of the hydraulic pump P is also produced when the cargo receiving tray 4 does not move from the floor position. do not have. This improves the quietness of operation.

(2) If there is a stopper for stopping the load receiving table 4 on the floor of the loading platform LP, it is necessary to retract the stopper from the elevating track of the subposts 2L and 2R when using the load receiving table 4 in the upper area. As a result, the stopper is generally exposed to the outside of the posts 1L and 1R, and the impact sound directly reaches the ears of the operator.

In this embodiment, there is a stopper 1e that mechanically defines the upper limit of the lifting range of the load receiving table 4, and this stopper 1e is housed inside the posts 1L and 1R. Therefore, unlike the stopper that stops the load receiving table at the floor position in a high-lift type load receiving table lifting device, in the case of the stopper 1e, the collision noise with the sub-posts 2L, 2R (or the sliders 3L, 3R) is generated by the posts 1L, 2R. mitigated.

(3) The sensor SN detects that the load receiving table 4 has reached the floor position due to the amount of extension of the hydraulic cylinder 6 housed in the cross member 5. The lifting device 100 can be configured compactly. In addition, the appearance becomes simpler, and the beauty is improved.

(4) In this embodiment, the first operating device O1 that moves the load receiving tray 4 in the lower area and the second operating device O2 that moves in the upper area are provided. As a result, for example, when the load receiving platform 4 is raised across the floor position, when the load receiving platform 4 stops at the floor position during the operation of the first operating device O1, the operation invalid state of the up button U1 is canceled. The second operation device O2 can be operated continuously without any special operation.

(5) In the circuit configuration illustrated in FIG. 5, the load receiving stand 4 can be operated by the second operating device O2 regardless of the position of the load receiving stand 4 in terms of the circuit. Therefore, by exclusively using the second operating device O2, the load receiving table 4 can be operated in the entire lifting range including the upper area and the lower area without being restricted by the automatic stop control of the load receiving table 4.

However, by separately providing the first operating device O1 assuming that the load receiving tray 4 is operated in the lower area, it is possible to move the load receiving tray 4 in the upper area or the lower area depending on the operating device to be used. can raise awareness of When aligning the load receiving platform 4 with the floor position of the loading platform LP, the load receiving platform 4 can be easily aligned by raising the load receiving platform 4 from the lower area using the first operating device O1. .

(Second embodiment)
FIG. 6 is a circuit diagram of the power unit of the vertical load receiving platform lifting device according to the second embodiment of the invention, and corresponds to FIG. 5 of the first embodiment. A difference of this embodiment from the first embodiment is that an on/off switch X for the sensor SN is provided. In this embodiment, an operating device corresponding to the second operating device O2 of the first embodiment can be omitted, and the wires E6 and E7 can also be omitted along with the omission of the second operating device O2. As the operating device in this embodiment, there is only one that corresponds to the first operating device O1 of the first embodiment. Although there is only one operating device, this embodiment is also referred to as a first operating device O1 in accordance with the first embodiment.

The on/off switch X can be placed, for example, inside the unit box 9a that houses the power unit 9, but in consideration of operational convenience, it is desirable to provide the on/off switch X on the first operating device O1 together with the up button U1 and the down button D1. . By cutting off the power supply to the sensor SN with the ON/OFF switch X, the coil CR1 is not excited even if the loading platform 4 is located on the floor of the loading platform LP, and the relay switch CR is activated regardless of the position of the loading platform 4. contact CR2 is always closed. Other configurations are the same as those of the first embodiment.

The basic effects (1) to (3) described above can be obtained in this embodiment as well as in the first embodiment.

Further, in the first embodiment, the case where the first operating device O1 and the second operating device O2 are selectively used depending on whether the load receiving table 4 is driven in the upper area or the load receiving table 4 is driven in the lower area is described as an example. . On the other hand, in the present embodiment, the load receiving tray 4 can be operated by the first operating device O1 in the entire elevation range including the upper area and the lower area.

That is, by switching the ON/OFF switch X and energizing the sensor SN (activating the function of the sensor SN), the load receiving platform 4 can be lifted from the lower area and automatically stopped at the floor surface position of the loading platform LP. .

On the other hand, the ON/OFF switch X cuts off the energization of the sensor SN (disables the function of the sensor SN), thereby invalidating the automatic stop control of the load receiving platform 4, and using the first operating device O1, for example, the loading platform LP. It is also possible to raise the load receiving table 4 from the lower area to the upper area across the floor surface position.

(Modification)
In each of the above embodiments, the automatic stop when the load receiving platform 4 descends from the upper area to the floor surface position of the loading platform LP is not mentioned, but the sensor detects this and the load receiving platform 4 is moved to the floor position. It is also possible to have a configuration in which the descent of the is automatically stopped. In this case, another sensor may be added to the sensor SN. However, for example, in the circuit diagram of the first embodiment (FIG. 5), adding a contact CR2 to the wire E7 of the lower button D2 of the second operating device O2 can simplify the operation. circuit can be constructed. In the circuit diagram (FIG. 6) of the second embodiment, a contact CR2 may be added to the wiring E4 of the lower button D1 of the first operating device O1.

Further, in the first embodiment, in terms of circuitry, buttons other than the upper button U1 of the first operating device O1 (the upper button U2 and the lower buttons D1 and D2) are always active (behavior of the sensor SN) while the power unit 9 is on. the operation takes effect. The operation of the lower button D1 of the first operating device O1 is also effective in the upper region, and the operation of the upper button U2 and the lower button D2 of the second operating device O2 is also effective in the lower region. However, if it is desired that the operation of the first operating device O1 is effective only in the lower area and the operation of the second operating device O2 is effective only in the upper area, the sensor detects in which area the receiving tray 4 is located. However, the configuration may be such that the operation of the first operating device O1 or the second operating device O2 is selectively validated.

Further, although the structure having the stopper 1e that defines the upper limit of the lifting range of the load receiving table 4 has been described as an example, the upper limit position can also be detected by a sensor and the load receiving table 4 can be automatically stopped.

Although the configuration in which the sensor SN is accommodated in the cross member 5 has been described as an example, the configuration is not limited to this configuration. For example, a sensor SN is provided on at least one of the posts 1L and 1R to detect the position of at least one of the sub-posts 2L and 2R or at least one of the sliders 3L and 3R, thereby detecting that the load receiving platform 4 is on the floor. can also be configured.

Further, in the first embodiment and the second embodiment, the storage position of the load receiving platform 4 is set to the floor position of the loading platform LP (the load receiving platform 4 is erected and stored at the floor position). However, in practice, the storage position may be set at a position deviated from the floor position of the loading platform LP. In this case, it is possible to provide a stopper for stopping the lifting or lowering movement of the load receiving table 4 at the retracted position, or to apply automatic stop control using a sensor to the retracted position.

Further, in the first embodiment and the second embodiment, the case where the set position for automatically stopping the load receiving table 4 is the floor position is described as an example, but this set position may be shifted from the floor position. If the storage position is shifted from the floor position (for example, if the storage position is slightly lower than the floor position), it is reasonable to shift the setting position from the floor position (set to a position lower than the floor position). is. In this case, a second sensor or stopper for stopping the load receiving tray 4 at the floor position may be provided, and a separate mechanism for stopping the load receiving tray 4 at the floor position during cargo handling operations in the upper area or the lower area may be provided.

Also, the case where the wire retainers 5a and 5b are provided on the inner wall of the cross member 5 has been described as an example, but the wire retainers 5a and 5b may be fixed to a stationary structure having a fixed relationship with the cross member 5. , for example, may be attached to the tube of the hydraulic cylinder 6 .

Also, although the sliders 3L and 3R are driven using pulleys and wires, chains may be used instead of the wires 8L and 8R, and sprockets may be used instead of the pulleys 7La-7Lc and 7Ra-7Rd. can also In this case, since a sprocket with a smaller diameter than the pulley can be used, the cross member 5 and the posts 1L and 1R can be slimmed down, leading to a reduction in the size of the load receiving table lifting device 100.

Although the sub-posts 2L and 2R are provided as an example, the sub-posts 2L and 2R can be omitted if the vertical range of the sliders 3L and 3R can be sufficiently ensured only by the posts 1L and 1R.

Although the wire 8L, 8R is wound twice around the moving pulleys 7La, 7Ra and the fixed pulley 7Lb, 7Rb, the wires 8L, 8R may be wound around the moving pulleys 7La, 7Ra and the fixed pulleys 7Lb, 7Rb twice. The number of turns may be further increased. If the stroke of the hydraulic cylinder 6 is the same, the greater the number of windings of the wires 8L, 8R, the more advantageous it is in expanding the lifting range of the load receiving table 4. If the wires 8L and 8R are wound only once around the movable pulleys 7La and 7Ra and the fixed pulleys 7Lb and 7Rb, such a configuration may be used.

Furthermore, the moving pulleys 7La and 7Ra and the fixed pulleys 7Lb and 7Rb are each a single pulley having a plurality of wire grooves. It is good as Also, although the movable pulleys 7La and 7Ra are separate pulleys, they may be integrally formed (for example, a pulley having four wire grooves may be substituted). The same applies to the fixed pulleys 7Lb and 7Rb.

1e Stopper 1L, 1R Post 4 Receiving platform 5 Cross member 6 Hydraulic cylinder 100 Vertical loading platform lifting device CR Relay switch (control device) LP Loading platform O1 Third 1 operating device, O2... second operating device, SN... sensor, X... on/off switch

Claims (6)

In the vertical loading platform lifting device mounted on the loading platform of the vehicle,
left and right posts,
a load receiving platform that is guided by the left and right posts and that can move up and down on the floor surface of the loading platform;
a hydraulic cylinder that drives the load receiving table up and down;
a sensor for detecting that the loading platform is in a set position;
a first operating device and a second operating device for operating the load receiving tray;
a control device having a function of stopping the hydraulic cylinder when the sensor detects that the load receiving platform has reached the set position ;
The control device controls the raising operation and lowering operation by the first operating device among the raising operation and lowering operation of the cargo receiving platform by the first operating device and the raising operation and lowering operation of the cargo receiving platform by the second operating device. A vertical loading platform lifting device configured to stop the hydraulic cylinder when the sensor detects that the loading platform has reached the set position only when at least one of the operations is performed. . 2. The vertical load receiving platform lifting device according to claim 1, wherein said set position is said floor surface position. 2. The vertical load receiving platform lifting device according to claim 1, further comprising a stopper provided inside said post for defining the upper limit of the lifting range of said load receiving platform. In the vertical loading platform lifting device of claim 1,
The hydraulic cylinder is accommodated in a cross member that connects the left and right posts,
A vertical type load receiving tray lifting device, wherein the sensor detects that the extension amount of the hydraulic cylinder is a predetermined value, and detection is made that the load receiving tray has reached the set position. In the vertical loading platform lifting device of claim 1,
The first operating device operates the load receiving platform in a lifting range below the set position,
The second operating device operates the load receiving platform in a lifting range above the set position.
Vertical loading platform lifting device. 2. The vertical load receiving platform lifting device of claim 1, further comprising an on/off switch for said sensor.

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