JP3792151B2 - Underfloor retractable lifting device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lifting device that is mounted on the rear part of a vehicle such as a lorry and that facilitates loading and unloading of a cargo by lifting and lowering the platform, and in particular, a floor retractable lifting mechanism having a structure in which the platform is folded and stored under the vehicle floor. Relates to the device.
[0002]
[Prior art]
Conventionally, as an elevating device to be mounted on a truck, it has been common to use a rear gate of a truck as a platform and lift a platform also serving as a rear gate with a link mechanism.
[0003]
By the way, in a structure in which the body of a lorry has no gate, for example, a structure having a double door, a slide door, an accordion door, a side-open roof, etc., the structure in which the platform also serves as the gate of the body is rather inconvenient.
[0004]
Therefore, the lifting device disclosed in Japanese Patent Application Laid-Open No. 8-150869 proposed by the present applicant has a structure in which the platform is folded and stored under the vehicle body floor in the folded state.
[0005]
[Problems to be solved by the invention]
By the way, in Japanese Patent Laid-Open No. 8-150869, apart from the lifting cylinder for lifting and lowering the deployed platform, one link of the lifting and lowering parallel link mechanism is expanded and contracted for the tilting operation to lower the tip of the platform after landing. Therefore, there is a problem that piping and control systems to a plurality of cylinders are complicated and cost is increased.
[0006]
[Problems to be solved by the invention]
In view of the above points, the first object of the present invention is to enable the platform to be moved up and down and tilted only by the lifting cylinder, to simplify the piping and control system associated with the cylinder installation, and to reduce the cost. An object of the present invention is to provide an underfloor retractable lifting device that can be used.
[0007]
The second object of the present invention is a subfloor retractable type in which the platform has a three-part structure, can be folded and stored compactly, can be applied to various vehicle types, and can have a sufficiently large platform in an unfolded state. The object is to provide a lifting device.
[0008]
A third object of the present invention is to provide an underfloor retractable lifting device capable of easily performing fine tilt adjustment for setting the platform horizontally by an adjustment mechanism.
[0009]
A fourth object of the present invention is to provide an underfloor retractable lifting device capable of reliably holding a platform stored under the floor in a folded state.
[0010]
Other objects and novel features of the present invention will be clarified in embodiments described later.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, an underfloor retractable lifting apparatus according to the invention of claim 1 of the present invention includes a main body frame that is slidable in the front-rear direction with respect to the chassis side of the vehicle,
A slide drive mechanism for pulling the main body frame under the floor of the vehicle;
It consists of a main plate, an intermediate plate rotatably connected to the front end side of the main plate, and a front end side plate rotatably connected to the front end side of the intermediate plate, and the upper surface is flat when deployed. Platform,
An elevating drive link mechanism for connecting the main body frame side and the base end side of the main plate to elevate and drive the platform;
The elevating drive link mechanism includes: a small arm having one end pivotally attached to the main body frame; a main arm having a base end pivotally attached to an intermediate position of the small arm; and the other end of the small arm; An elevating cylinder connected between the leading ends of the main arm, a stopper fixed to the main body frame for preventing the small arm from rotating due to a reaction force of the elevating cylinder extending, and a leading end of the main arm A vertical link body having an upper end pivotally attached thereto, a sub arm connected between the main body frame and the lower end portion of the vertical link body so as to form a parallel link with the main arm, and an attachment connected to the front end of the main arm A bracket body, and the main plate is connected to the mounting bracket body so as to maintain a horizontal state in a deployed state ,
An adjustment mechanism that adjusts the positional relationship between the lower side of the mounting bracket body and the lower side of the vertical link body to adjust the inclination of the mounting bracket body and the platform connected thereto;
After the vertical link body is in the landing state, the vertical arm is further moved by further contracting the lifting cylinder to separate the small arm from the stopper and move the position of the main arm base end portion. And the mounting bracket body is tilted, and the tip of the deployed platform is lowered.
The platform is foldable by folding the tip side plate over the intermediate plate and folding the intermediate plate with the tip side plate over the main plate so that the platform is folded. A receiving roller that supports the lower surface of the platform when it is reversed to the upper side of the main arm is supported on the main body frame side .
[0015]
Underfloor retractable lifting device according to the invention according to claim 2, in claim 1, when storing the platform of the body frame and folded condition to the vehicle floor by the slide drive mechanism, provided on the platform side A wedge-shaped piece is fitted into a concave portion of a holding member fixed to the chassis side.
[0016]
The underfloor retractable lifting device according to the invention of claim 3 of the present application is characterized in that, in claim 1 or 2 , a torsion bar for urging the main plate to stand is provided between the mounting bracket body and the main plate. It is characterized by being.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an underfloor retractable lifting apparatus according to the present invention will be described below with reference to the drawings.
[0018]
In FIG. 1 to FIG. 9, for example, a box-shaped vehicle body 2 is mounted and fixed on a chassis 1 of a truck, and a fixed frame 4 of a floor retractable lifting device is fixed to a rear portion of the chassis 1 of the truck. ing. A square pipe-shaped slide guide 5 with a slit is fixed to the fixed frame 4.
[0019]
The main body frame 10 of the underfloor retractable lifting device includes a square pipe 11 as a connecting member, brackets 12 and 13 fixed to both sides thereof, and brackets on both sides, as shown in FIGS. The runners 14 are also fixed to the outer periphery of the square pipe 11 by fastening members 19 integrated at the bottom.
[0020]
A runner 14 integrated with the main body frame 10 is provided so as to be slidable in the lateral direction (front-rear direction of the vehicle) with respect to the slide guide 5. That is, a rectangular plate-like sliding member 14a having a wear resistance and a small friction coefficient, such as nylon resin, slidably in contact with the upper and lower inner surfaces of the slide guide 5 is fixed to both ends of the upper portion of the runner 14. Slides smoothly in the slide guide 5 without rattling. The lower portion of the runner 14 extends downward through the slit of the slide guide 5 and is connected to the square pipe 11. As shown in FIG. 6, the interval between the fixed frames 4 is determined by the width of the chassis 1, and the width of the chassis 1 varies depending on the vehicle type, but by changing the tightening fixing position of the tightening member 19 to the square pipe 11, The distance between the runners 14 can be adjusted in accordance with the distance between the slide guides 5 on the fixed frame 4 side, and can be adapted to various vehicle types.
[0021]
A slide drive hydraulic cylinder 15 for moving the runner 14 in the lateral direction (front-rear direction) is attached between the fixed frame 4 side, that is, between the extended end of the slide guide 5 and the runner 14. A slide drive mechanism that drives the main body frame 10 in the lateral direction (front-rear direction) is constituted by a runner 14 that slides in the slide guide 5. That is, when the piston rod of the cylinder 15 is extended, the main body frame 10 (runner 14) approaches the rear end side of the floor portion 3 of the vehicle body 2, and conversely, when the piston rod is contracted, the main body frame 10 is in the back direction below the vehicle body floor. It will be in the state pulled in.
[0022]
As shown in FIG. 7, the upper end of the small arm 20 is pivotally attached (rotatably mounted) to the bracket 12 of the main body frame 10 by a pin 21, and the lower contact portion 20 a of the small arm 20 is located on the square pipe 11 side. It comes into contact with the stopper 16. The base end portion of the main arm 25 is pivotally attached to the middle position of the small arm 20 with a pin 26, and the distal end portion is pivotally attached to the upper end portion of the vertical link body 30 with a pin 31. An elevating hydraulic cylinder 27 is pivotally attached by pins 28 and 29 between the lower end of the small arm 20 and a position near the tip of the main arm 25. Further, a sub arm 35 is pivotally connected by pins 36 and 37 between the bracket 13 of the main body frame 10 and the lower end portion of the vertical link body 30. The main arm 25 and the sub arm 35 constitute a lifting drive link mechanism, and when the lower contact portion 20a of the small arm 20 is kept in contact with the stopper 16 on the square pipe 11 side, Pins 26 and 31 and pins 36 and 37 at both ends of the sub arm 35 are located at the apexes of the parallelogram, and when the lifting hydraulic cylinder 27 is contracted, the tip of the main arm 25 is lowered and extended. Sometimes the tip of the main arm 25 is in the raised position. The rotation of the small arm 20 due to the reaction force when the cylinder 27 is extended is prevented by the lower contact portion 20a contacting the square pipe side stopper 16.
[0023]
As shown in FIG. 7, the bracket 12 is provided with a sensor 39 for defining the ascending limit position of the main arm 25, and a pipe member 25a for connecting and fixing two plate members constituting the main arm 25 is provided in the main arm 25. The arm 25 comes into contact with the detection end of the sensor 39 at the ascending limit position. When the detection end of the sensor 39 is pushed, the operation of the lifting hydraulic cylinder 27 is stopped.
[0024]
The upper base end side of the mounting bracket body 40 shown in FIG. 8 is pivotally attached to the pin 31 in common with the upper end portion of the vertical link body 30, and the adjusting mechanism 50 is attached to the lower portion of the mounting bracket body 40. This adjustment mechanism 50 has an adjustment bolt 52 screwed to the vertical portion 41 of the mounting bracket body 40 via a fixing bolt 51, and the tip of the adjustment bolt 52 is provided at the lower portion of the vertical link body 30 ( The threaded pin 53 is fitted into the female threaded portion of the threaded pin 53. The reinforcing plate 54 is fixed along the inside of the vertical portion 41 of the mounting bracket body 40. Then, by adjusting the rotation amount of the adjustment bolt 52, the positional relationship between the lower side of the mounting bracket body 40 and the lower side of the vertical link body 30 can be adjusted to adjust the inclination of the mounting bracket body 40 (as a result). The inclination of the lifting platform 60 described later can be adjusted.) When the rotation amount of the adjustment bolt 52 is determined, the adjustment bolt 52 is fixed at the rotation position by the fixing bolt 51.
[0025]
The elevating platform 60 includes a main plate 61, an intermediate plate 62 rotatably connected to the front end side of the main plate, and a front end side plate 63 rotatably connected to the front end side of the intermediate plate. These are connected to each other by a double hinge (double hinge having two rotation fulcrums) 64 so as to be foldable. The main plate 61, the intermediate plate 62, and the tip side plate 63, when deployed in a flat plate shape, the reinforcing material 61 a on the back side of the main plate 61 and the reinforcing material 62 a on the back side of the intermediate plate 62, and the end face of the intermediate plate 62 and the tip side plate 63. The end surfaces are abutted and function as a single flat platform with a flat upper surface. Further, in the folded state, the tip side plate 63 is turned over and overlapped on the intermediate plate 62, and these are turned over and overlapped on the main plate 61.
[0026]
The mounting bracket body 40 and the base end portion of the main plate 61 are rotatably connected by a link 65. That is, one end of the link 65 is pivotally attached to the mounting bracket body 40 by a pin 66, the other end is pivotally attached to the main plate 61 by a pin 67, and the link 65 and the pins 66 and 67 function as a double hinge. It has become. When the elevating platform 60 is deployed, the vertical portion 41 of the mounting bracket body 40 and the reinforcing member 61a on the back side of the main plate 61 come into contact with each other, so that the main plate 61 is maintained in a horizontal state with respect to the mounting bracket body 40.
[0027]
A platform support arm 70 is fixed to a position near the center of the square pipe 11, and this platform support arm 70 extends horizontally to the rear side of the chassis 1 of the lorry, and the front end (rear end) of the support arm 70. The receiving roller 71 is pivotally attached to the bracket. The receiving roller 71 functions to abut against and support the back side of the intermediate plate 62 when the lifting platform 60 is folded and stored as shown in FIGS.
[0028]
As shown in FIGS. 8A, 8 </ b> B, and 8 </ b> C, the direction in which the main plate 61 stands vertically with respect to the mounting bracket body 40 is between the mounting bracket body 40 and the main plate 61 of the platform 60. A pair of torsion bars 75 for energizing is provided. That is, one bent end portion 75a of the torsion bar 75 passes through the pins 66 and 67 that stop the link 65 connecting the mounting bracket body 40 and the main plate 61 to prevent the pins 66 and 67 from coming off, and the other bent end 75a. The portion 75b is fixed to the back side of the main plate 61. Between the main plate 61 and the intermediate plate 62, a torsion bar 76 that urges the intermediate plate 62 in a direction to stand up vertically with respect to the main plate 61 is provided. Further, a torsion bar having the same function may be provided between the intermediate plate 62 and the tip side plate 63 as necessary.
[0029]
A wedge-shaped piece 80 fixed to the vertical mounting plate 81 is fixed to the back side of the main plate 61. On the other hand, as shown in FIGS. 3 and 4, a holding member 85 having a recess 86 corresponding to the wedge-shaped piece 80 is a chassis. It is fixed on the 1 side. Then, when the lift platform 60 in the folded state from the state of FIG. 3 is pulled into the floor of the lorry as shown in FIG. 4, the wedge-shaped piece 80 is fitted in the recess 86. With this mechanism, the folded lifting platform 60 is prevented from being damaged by vibration or generating noise when the lorry is traveling.
[0030]
Next, the operation of the embodiment of the underfloor retractable lifting device will be described.
[0031]
When performing normal cargo handling work, as shown in FIG. 1, the slide drive hydraulic cylinder 15 is extended and the runner 14 and the main body frame 10 are slid close to the floor end of the vehicle body 2. The main plate 61, the intermediate plate 62, and the tip side plate 63 constituting the 60 are unfolded in a flat plate shape (folding and unfolding operations of the elevating platform 60 are performed manually). Then, by extending or contracting the lifting hydraulic cylinder 27 that drives the main arm 25 included in the lifting drive link mechanism, the main arm 25 and the sub arm 35 in the parallel link state are rotated, and the platform 60 is shown in FIG. From the landing state of the solid line (A) to the position of the solid line (B) of the height of the floor surface 3A (the upper surface of the floor portion 3) of the vehicle body 2, the horizontal state is maintained and raised, or from the height of the floor surface 3A The vehicle can be lowered to the landing state, and by using such a lifting operation of the platform 60, a cargo handling operation from the ground to the vehicle body floor or from the vehicle body floor to the ground can be performed. Further, when the lifting hydraulic cylinder 27 is further contracted in the landing state of the lifting platform 60, the lower contact portion 20a of the small arm 20 is separated from the stopper 16 on the square pipe 11 side, and the mounting support point of the main arm 25 is reached. Since the (pin 26) moves to the rear side of the vehicle body 2, the lifting / lowering platform 60 is tilted as shown by an imaginary line (c) in FIG. 1 to carry in or carry out the cargo on the platform 60 in the landing state. It can also be performed efficiently.
[0032]
The platform retracting operation after normal cargo handling is completed as follows. In the landing state of the elevating platform 60 in FIG. 1 (a) or (c), first, the tip side plate 63 is turned over on the intermediate plate 62, and then both are reversed as shown in FIG. Fold over the plate 61. This operation can be easily performed by manual operation by the action of the torsion bar 76 of FIG. 8 that urges the intermediate plate 62 to stand vertically with respect to the main plate 61.
[0033]
Next, the main plate 61 is raised with respect to the mounting bracket body 40 and leans so that the back side of the intermediate plate 62 contacts the receiving roller 71 at the tip of the support arm 70 as shown in FIG. Then, by extending the lifting hydraulic cylinder 27, the main arm 25 and the sub arm 35 are substantially horizontal as shown in FIG. 3, and the folded lifting platform 60 is placed on the receiving roller 71.
[0034]
When the slide drive hydraulic cylinder 15 is contracted from the state of FIG. 3, the lift platform 60 folded as shown in FIG. 4 is drawn under the floor of the vehicle body 2, and the wedge-shaped piece 80 on the platform 60 side is moved to the chassis 1 side. Fit into the recess 86.
[0035]
The operation of unfolding the lifting platform 60 so that cargo handling is possible is the reverse of the storage operation. First, the slide drive hydraulic cylinder 15 is extended to attach the runner 14 and the main body frame 10 to the floor 3 of the vehicle body 2. Then, the lifting and lowering hydraulic cylinder 27 is contracted to lower the main arm 25 and the sub arm 35 until they reach a landing state, and the folded lifting platform 60 is developed to form a single flat plate-like shape. The platform shape.
[0036]
According to this embodiment, the following effects can be obtained.
[0037]
(1) The platform can be lifted and tilted only by the lifting hydraulic cylinder 27 and the lifting link mechanism, the piping and control system associated with the installation of the hydraulic cylinder can be simplified, and the cost can be reduced. . That is, the base end portion of the main arm 25 is not directly pivotally attached to the main body frame 10 but is connected to the main body frame 10 via the small arm 20, and after the vertical link body 30 is in the landing state, the lifting hydraulic cylinder 27 Is further contracted to move the small arm 20 away from the stopper 16 on the main body frame 10 side, and the position of the base end portion of the main arm 25 moves (moves rearward), so that the vertical link body 30 and the mounting bracket body 40 can be tilted, and a tilting operation can be performed in which the tip of the deployed platform 60 is lowered.
[0038]
(2) During normal handling, the elevating platform 60 can be driven up and down while maintaining the horizontal state by the elevating link mechanism, and the elevating platform 60 can be used to smoothly perform the cargo handling operation. Further, the elevating platform 60 is formed by connecting three plates of the main plate 61, the intermediate plate 62, and the front end side plate 63, and the elevating platform 60 can be stored compactly under the floor of the vehicle body. For this reason, an applicable vehicle type spreads. Further, the deployed platform 60 can have a sufficient area.
(3) Since the adjustment mechanism 50 is provided between the mounting bracket body 40 connected to the lifting platform 60 and the vertical link body 30 forming the vertical portion of the lifting parallel link mechanism as shown in FIG. The inclination of the mounting bracket body 40 and thus the inclination of the lifting platform 60 can be finely adjusted. That is, it is possible to finely adjust the level of the lifting platform 60 during deployment.
[0040]
(4) As shown in FIG. 8, a torsion bar 75 is provided between the mounting bracket body 40 and the main plate of the elevating platform 60 to urge the main plate 61 in a standing direction, and the main plate 61 and the intermediate plate 62 are further provided. Since the torsion bar 76 that urges the intermediate plate 62 to stand vertically with respect to the main plate 61 is provided in between, the folding platform 60 can be easily folded and unfolded by manual operation. It is.
[0041]
(5) A wedge-shaped piece 80 provided on the platform 60 side when the main body frame 10 and the folded platform 60 are stored under the vehicle floor by the slide drive mechanism (slide guide 5, runner 14 and slide drive hydraulic cylinder 15). Is fitted into the recess 86 on the main body frame 10 side, so that it is possible to prevent the folding platform 60 in a folded state from vibrating and generating noise or being damaged when the vehicle is traveling.
[0042]
Although the embodiments of the present invention have been described above, it will be obvious to those skilled in the art that the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the claims.
[0043]
【The invention's effect】
As described above, according to the underfloor retractable lifting device according to the present invention, the platform can be lifted and tilted only with the lifting cylinder, the piping and control system associated with the cylinder installation can be simplified, and the cost can be reduced. Reduction can be achieved.
[00044]
Further, since the platform has a three-part structure, it can be folded and stored compactly, can be applied to various vehicle types, and the platform in the deployed state can have a sufficient area.
[Brief description of the drawings]
FIG. 1 is a side view illustrating a lifting operation of a lifting platform, which is an embodiment of an underfloor retractable lifting apparatus according to the present invention.
FIG. 2 is a side view showing a folding operation of the lifting platform in the embodiment.
FIG. 3 is a side view showing a state before storage when the lifting platform is completely folded in the embodiment;
FIG. 4 is a side view showing a storage completion state of the elevating platform in the embodiment.
FIG. 5 is a plan view showing a state in which the elevating platform in the embodiment has been stored, with a part of the elevating platform cut away.
FIG. 6 is a front view of the same.
FIG. 7 is a side view mainly showing a lifting link mechanism portion in the embodiment.
FIGS. 8A and 8B show a state where folding of the lifting platform in the embodiment is completed, in which FIG. 8A is a side view, FIG. 8B is a plan view, and FIG.
FIG. 9 is a side view showing a vertical link body, a mounting bracket body, and an adjustment mechanism in the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Chassis 2 Car body 3 Floor part 4 Fixed frame 5 Slide guide 10 Main body frame 11 Square pipe 12, 13 Bracket 14 Runner 15 Rectangular plate-shaped sliding member 16 Stopper 19 Fastening member 20 Small arm 25 Main arm 27 Lifting hydraulic cylinder 30 Vertical Link body 35 Sub arm 40 Mounting bracket body 50 Adjustment mechanism 51 Fixing bolt 52 Adjustment bolt 53 Screw cutting pin 60 Elevating platform 61 Main plate 62 Intermediate plate 63 Tip side plate 70 Platform support arm 71 Receiving rollers 75, 76 Torsion bar 80 Wedge-shaped piece 85 Holding member 86 Recess

Claims (3)

A body frame (10) slidable in the front-rear direction with respect to the chassis side of the vehicle;
A slide drive mechanism for pulling the main body frame under the floor of the vehicle;
The main plate (61) is composed of an intermediate plate (62) rotatably connected to the front end side of the main plate and a front end plate (63) rotatably connected to the front end side of the intermediate plate. A platform (60) whose upper surface is flat in the state;
An elevating drive link mechanism for connecting the main body frame side and the base end side of the main plate to elevate and drive the platform;
The elevating drive link mechanism includes a small arm (20) having one end pivotally attached to the main body frame, a main arm (25) pivotally attached to an intermediate position of the small arm, and the small arm. An elevating cylinder connected between the other end of the arm and the front end side of the main arm, and a stopper fixed to the main body frame for preventing the small arm from rotating due to a reaction force of the elevating cylinder extending (16 ) , A vertical link body (30) whose upper end is pivotally attached to the front end of the main arm, and a sub arm connected between the main body frame and the lower end of the vertical link body so as to form a parallel link with the main arm. and (35), said and a mounting bracket member coupled to the main arm tip (40), said main plate is a concatenated configured to maintain the horizontal in the deployed state to the mounting bracket body ,
An adjustment mechanism (50) for adjusting the positional relationship between the lower side of the mounting bracket body and the lower side of the vertical link body and adjusting the inclination of the mounting bracket body and the platform connected thereto ;
After the vertical link body is in the landing state, the vertical arm is further moved by further contracting the lifting cylinder to separate the small arm from the stopper and move the position of the main arm base end portion. And the mounting bracket body is tilted, and the tip of the deployed platform is lowered.
The platform is foldable by folding the tip side plate over the intermediate plate and folding the intermediate plate with the tip side plate over the main plate so that the platform is folded. An underfloor retractable lifting device , wherein a receiving roller (71) that supports the lower surface of the platform when the base is inverted to the upper side of the main arm is supported on the main body frame side . When the main body frame and the folded platform are stored under the vehicle floor by the slide drive mechanism, a wedge-shaped piece (80) provided on the platform side is a recess ( 85) fixed to the chassis side ( underfloor retractable lifting device according to claim 1, wherein the fitting 86). The underfloor retractable lifting device according to claim 1 or 2, wherein a torsion bar that urges the main plate in a direction to stand up is provided between the mounting bracket body and the main plate.

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