JP5665292B2 - Underfloor retractable lifting device - Google Patents

Description

  The present invention relates to a lifting device that is mounted on the rear part of a vehicle such as a lorry to facilitate the loading and unloading of cargo by lifting and lowering the platform, and in particular, it can be stored under the floor with a structure in which the platform is folded and stored under the vehicle floor. Relates to the device.

  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.

  By the way, in a structure in which the body of a lorry does not have a 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 inconvenient.

  Therefore, in the lifting device disclosed in Patent Document 1 proposed by the present applicant, the platform is configured to be folded, and the platform is folded and stored under the vehicle body floor.

JP 2003-175760 A

  By the way, in patent document 1, the raising / lowering platform is a three-plate structure of a main plate, an intermediate | middle plate, and a front end side plate, and it folds in three and is folded manually. Further, the operation of unfolding from a folded state onto a single flat platform is also manual. For this reason, when the lifting platform is soiled with mud or the like, the operator's hand is soiled by a manual unfolding operation, which may cause inconvenience of handling food items or the like with the soiled hand.

  The present invention has been made in view of such a situation. The purpose of the present invention is to automatically fold the lifting platform and store it under the floor, and to automatically unfold it from the folded state into a flat plate shape. An object of the present invention is to provide an underfloor retractable lifting device that does not bother a hand and saves labor in cargo handling work.

  Another object of the present invention is to provide an underfloor retractable lifting device that automates the folding and folding operations of the lifting platform and the flat plate by using an opening / closing cylinder and a simple link mechanism.

  Other objects and novel features of the present invention will be clarified in embodiments described later.

In order to achieve the above object, an underfloor retractable lifting apparatus according to an aspect 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;
A main plate, a front end plate that is rotatably connected to the front end side of the main plate by a double hinge, and an elevating platform whose upper surface is a flat plate shape in a deployed 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;
A double-acting hydraulic cylinder for opening and closing disposed on the lower surface side of the main plate;
A guide rail that guides the upper and lower sides of the piston rod tip position so that the piston rod tip position of the double-acting hydraulic cylinder for opening and closing moves linearly,
An end of the main body of the open / close double-acting hydraulic cylinder is pivotally attached to the lower surface side of the main plate, and one end of an open / close link is pivotally attached to a piston rod end of the open / close double-acting hydraulic cylinder. The other end is pivotally attached to the tip side plate,
When the double-acting hydraulic cylinder for opening and closing is extended, the tip side plate is turned upside down to be in a folded state overlapping the main plate.

In the above aspect, the pivot points of the both ends of the opening / closing link are located on or near a straight line in the axial direction of the opening / closing double-acting hydraulic cylinder in the deployed state of the platform. It is good in the structure which the said front end side plate rotates by setting the pivot point to the said front end side plate of the connection link which a hinge has as a rotation fulcrum.

  In the above aspect, the opening / closing link may be bent so as to avoid contact of the main plate and the tip side plate with the double side hinge by the double hinge.

In the above aspect, the elevating drive link mechanism includes a small arm whose one end is pivotally attached to the main body frame, a base end which is pivotally attached to an intermediate position of the small arm, and the other end which is the main plate. A main arm pivotally attached to the upper part on the base end side, an elevating hydraulic cylinder connected between the other end of the small arm and the distal end side of the main arm, and the reaction force of the elevating hydraulic cylinder extending A stopper provided on the main body frame for preventing the small arm from rotating, and a sub arm connected between the main body frame and a lower portion on the base end side of the main plate so as to form a parallel link with the main arm. It is good to have. In this case, the small arm is moved away from the stopper by further contracting the lifting hydraulic cylinder after the base end side of the main plate is in the landing state, and the position of the main arm base end is moved. Thus, a configuration in which the tip of the unfolded platform is lowered may be employed.

  It should be noted that any combination of the above-described constituent elements, and those obtained by converting the expression of the present invention between methods and systems are also effective as aspects of the present invention.

  According to the underfloor retractable lifting device according to the present invention, the lifting platform can be automatically folded and stored under the floor, and can be automatically expanded into a flat shape from the folded state so as not to bother the operator. Thus, labor saving of cargo handling work can be achieved. Furthermore, the lifting and lowering platform folding and unfolding operations can be automated by an open / close cylinder and a simple link mechanism.

It is an embodiment of the underfloor retractable lifting device according to the present invention and is a side view for explaining the lifting operation of the lifting platform. It is a side view which shows the state before storage by the completion of folding of the raising / lowering platform in embodiment. It is a side view which shows the storage completion state of the raising / lowering platform in embodiment. It is a side view which mainly shows the raising / lowering platform in embodiment. It is a side view which mainly shows the link mechanism part for raising / lowering in embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or equivalent component, member, process, etc. which are shown by each drawing, and the overlapping description is abbreviate | omitted suitably. In addition, the embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  1 to 3 show an overall configuration of an embodiment of the present invention. In these drawings, a box-shaped vehicle body 2 is mounted and fixed on a chassis 1 of a lorry, and a fixed frame 4 of an underfloor retractable lifting device is fixed to a rear portion of the chassis 1 of the lorry. . A rectangular pipe-shaped slide guide 5 with slits is fixed to both sides of the chassis 1 in the horizontal direction on the fixed frame 4. The slits of the square pipe-shaped slide guide 5 are provided for passing a runner 14 described later.

  As shown in FIGS. 1 to 4A and 4B, 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 both sides. A pair of runners 14 provided on the inner side of the bracket, and a lower portion of the runners 14 is fixed to the outer periphery of the square pipe 11.

  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.

  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 3 of the vehicle body 2 as shown in FIG. The main body frame 10 is in a state of being pulled in the back direction under the vehicle body floor. Although details are omitted, the slide drive hydraulic cylinder 15 may have a double cylinder or two-stage cylinder structure in order to increase the stroke.

  As shown in FIGS. 4A and 4B, the elevating platform 60 connected to the main body frame 10 via the elevating drive link mechanism is rotatable to the main plate 61 and the distal end side thereof. It consists of the front end side plate 62 connected, and both plates are connected by a double hinge (double hinge having two rotation fulcrums) 64 so as to be foldable. That is, one of the small connecting links 65 of the double hinge 64 is connected to the upper part of the tip of the main plate 61 at a pivot point (rotation fulcrum) 66, and the other is connected to the top of the tip side plate 62 at a pivot point (rotation fulcrum) 67. It is connected to the upper part of the base end.

  When the main plate 61 and the tip side plate 62 are flattened, the reinforcing material on the back side of the main plate 61 and the reinforcing material on the back side of the tip side plate 62 (or the end surfaces of both plates 61 and 63) are abutted to each other. Is designed to function as a single flat plate platform. Further, in the folded state, the front end side plate 62 is turned over and overlaid on the main plate 61.

  In order to automatically open and close the lifting platform 60, an opening / closing hydraulic cylinder (double-acting hydraulic cylinder) 70 is disposed on the lower surface side of the main plate 61. That is, the end of the main body of the opening / closing hydraulic cylinder 70 is fixedly attached to the lower surface of the main plate 61 with a fixture (pivotally attached to the lower surface side by the pin 70a), and one end of the opening / closing link 71 is connected to the opening / closing hydraulic cylinder 70. The other end of the opening / closing link 71 is pivotally attached to a bracket 72 integral with the lower portion of the proximal end portion of the distal end side plate 62. Here, the pivot points 71 a and 71 b at both ends of the opening and closing link are on a straight line in the axial direction of the opening and closing hydraulic cylinder 70 in the deployed state of the platform 60 (or in the vicinity of the straight line). Therefore, at the initial stage of the platform folding operation in which the opening / closing hydraulic cylinder 70 starts to extend, the distal end side plate 62 rotates with the pivot point 67 of the small link 65 of the double hinge 64 to the distal end side plate 62 as a rotation fulcrum. To do. Accordingly, the opening / closing link 71 can be prevented from hindering the rotation of the distal end side plate 62. Further, the opening / closing link 71 is curved in an arc shape so as to avoid contact of the main plate 61 and the front side plate 62 with the double hinge 64 on the connection side edge (when the platform is deployed, the opening / closing link 71 is provided). 4B, a roller 75 is pivotally attached to the piston rod tip position of the open / close hydraulic cylinder 70 (the pivot point 71a of the open / close link 71) as shown in FIG. The roller 75 is guided so as to move linearly by a guide rail 76 fixed to the lower surface side of the main plate 61.

  When the opening / closing hydraulic cylinder 70 is extended from the unfolded state of the platform 60, the tip side plate 62 starts to rotate at the pivot point 67 as a rotation fulcrum, but thereafter the main plate 61 of the small connecting link 65 is used. Further, rotation about the pivot point 66 on the side is also added, and finally, the distal end side plate 62 is turned over and overlapped with the main plate 61.

  The operation of the platform 60 from the folded state to the unfolded state can be performed by a reverse operation due to the contraction of the opening / closing hydraulic cylinder 70.

  As shown in FIG. 5, the upper end of the small arm 20 is pivotally attached to the bracket 12 of the main body frame 10 by a pin 21 (rotatably attached), and the lower abutting portion 20a of the small arm 20 faces the square pipe 11 side. The stopper portion 16 is provided in contact with the stopper portion 16. The base end portion of the main arm 25 is pivotally attached to the middle position of the small arm 20 by a pin 26, and the distal end portion is pivotally attached to the base end side upper portion of the main plate 61 by 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 part on the base end side of the main plate 61. 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 in contact with the stopper 16 on the square pipe 11 side, both ends of the main arm 25 are maintained. The pins 26 and 31 and the pins 36 and 37 at both ends of the sub arm 35 are respectively located at the apexes of the parallelogram, and the lift platform 60 in the unfolded state maintains a horizontal state. When the lifting hydraulic cylinder 27 is contracted, the tip of the main arm 25 is lowered (the platform 60 is lowered), and when it is extended, the tip of the main arm 25 is in the raised position (the platform 60 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.

  Next, the operation of the embodiment of the underfloor retractable lifting device will be described.

  When performing normal cargo handling work, as shown in FIGS. 1A and 1B, the slide drive hydraulic cylinder 15 is extended, and the runner 14 and the main body frame 10 slide close to the floor end of the vehicle body 2. The main plate 61 and the distal end side plate 62 constituting the elevating platform 60 are expanded in a flat plate shape (the elongating operation of the elevating platform 60 is performed by contracting the open / close hydraulic cylinder 70). 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. While maintaining the horizontal state from the landing state of the imaginary line (A) to the position of the solid line (B) of the height of the floor surface 3A (the upper surface of the floor 3) of the vehicle body 2, the height of the floor surface 3A The platform 60 can be lowered to the landing state, and by using such a lifting and lowering operation of the platform 60, a cargo handling operation from the ground to the vehicle body floor surface or from the vehicle body floor surface to the ground can be performed.

  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 (see FIG. 5), and the main arm 25 Since the mounting fulcrum (pin 26) moves to the rear side of the vehicle body 2, the lifting / lowering platform 60 is tilted as shown by the phantom line (c) in FIG. 1 to carry the luggage onto the platform 60 in the landing state. Or it can also be made to carry out efficiently.

  The platform retracting operation after normal cargo handling is completed as follows. In an intermediate state between FIGS. 1A and 1C, that is, in a deployed state of the lifting platform 60 in which the main arm 25 and the sub arm 35 are in a substantially horizontal state (lateral direction), the opening / closing hydraulic cylinder 70 is extended. Rotates the tip side plate 62 around the pivot point 67 as a rotation fulcrum, and then rotates around the pivot point 66 on the main plate 61 side of the small connecting link 65. Finally, the tip side plate 62 is moved. Turn over and fold over the main plate 61 (see FIG. 2).

  By retracting the slide drive hydraulic cylinder 15 from the state of FIG. 2, the lift platform 60 folded as shown in FIG. 3 is drawn under the floor of the vehicle body 2 and stored.

  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 hydraulic cylinder 70 for opening and closing is contracted to expand the lift platform 60 in a folded state to form a single flat platform shape. Thereafter, the lifting hydraulic cylinder 27 is contracted or extended to drive the platform 60 up and down via the main arm 25 and the sub arm 35.

  According to this embodiment, the following effects can be obtained.

(1) The elevating platform 60 formed by connecting the main plate 61 and the distal end side plate 62 with the double hinge 64 can be automatically folded and stored under the floor of the vehicle body 3, and is automatically flattened from the folded state. It can be deployed, so that the operator's hands are not bothered, and labor saving work can be achieved.

(2) The folding operation of the lifting platform 60 and the unfolding operation into a flat plate shape can be automated by the opening / closing hydraulic cylinder 70 and a simple link mechanism. Specifically, the main body of the opening / closing hydraulic cylinder 70 is attached to the lower surface side of the main plate 61, one end of the opening / closing link 71 is pivotally attached to the tip of the piston rod of the opening / closing hydraulic cylinder 70, and the other end of the opening / closing link 71. Is pivotally attached to the distal side plate 62. Further, when the platform 60 is deployed, the pivot points 71a and 71b at both ends of the opening and closing link 71 are on a straight line in the axial direction of the opening and closing hydraulic cylinder 70 (or in the vicinity of the straight line). By making 71 a curved shape in an arc shape, it is possible to prevent the opening / closing link 71 from coming into contact with the connection side edge of the main plate 61 and the tip side plate 62 by the double hinge 64 during the opening / closing operation of the platform 60. Yes.

(3) The platform can be lifted and lowered only by the lifting hydraulic cylinder 27 and the lifting link mechanism. 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 the lifting / lowering hydraulic pressure after the main plate 61 of the platform 60 is in the landing state. When the cylinder 27 is further contracted, the small arm 20 is separated from the stopper 16 on the main body frame 10 side, and the position of the base end portion of the main arm 25 is moved (moved toward the rear of the vehicle body). A tilting operation in which the tip is lowered can be performed.

  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.

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 Slide drive hydraulic cylinder 16 Stopper 20 Small arm 25 Main arm 27 Lifting hydraulic cylinder 35 Sub arm 60 Lifting platform 61 Main plate 62 End plate 64 Double hinge 70 Opening / closing hydraulic cylinder 71 Opening / closing link

Claims (5)

A body frame 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;
A main plate, a front end plate that is rotatably connected to the front end side of the main plate by a double hinge, and an elevating platform whose upper surface is a flat plate shape in a deployed 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;
A double-acting hydraulic cylinder for opening and closing disposed on the lower surface side of the main plate;
A guide rail that guides the upper and lower sides of the piston rod tip position so that the piston rod tip position of the double-acting hydraulic cylinder for opening and closing moves linearly,
An end of the main body of the open / close double-acting hydraulic cylinder is pivotally attached to the lower surface side of the main plate, and one end of an open / close link is pivotally attached to a piston rod end of the open / close double-acting hydraulic cylinder. The other end is pivotally attached to the tip side plate,
An underfloor retractable lifting device, wherein when the open / close double-acting hydraulic cylinder is extended, the tip side plate is turned upside down and overlaps the main plate. The underfloor retractable lifting device according to claim 1, wherein pivot points of both ends of the opening / closing link are located on or near a straight line in the axial direction of the opening / closing double-acting hydraulic cylinder in the deployed state of the platform. An underfloor retractable lifting device in which the tip side plate rotates around a pivot point of the connecting link of the double hinge on the tip side plate at the initial stage of the folding operation.   The underfloor retractable lifting device according to claim 1 or 2, wherein the opening / closing link is bent so as to avoid contact of the main plate and the tip side plate with an edge on a connection side by the double hinge. Type lifting device. The underfloor retractable lifting device according to claim 1, 2, or 3, wherein the lifting 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 pivotally attached to an upper part on the base end side of the main plate;
A lifting hydraulic cylinder connected between the other end of the small arm and the leading end of the main arm;
A stopper provided on the body frame for preventing the small arm from rotating due to a reaction force of the lifting hydraulic cylinder extending;
An underfloor retractable lifting device having a sub-arm connected between the main body frame and a lower portion on the base end side of the main plate so as to form a parallel link with the main arm. 5. The underfloor retractable lifting apparatus according to claim 4, wherein the small arm is separated from the stopper by further contracting the lifting hydraulic cylinder after the base end side of the main plate is in a landing state, and the main arm An underfloor retractable lifting device that performs an operation of lowering the distal end of the deployed platform when the position of the base end portion moves.

Images