JP2014201098A - Vehicle-mounted cargo handling platform lifting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle-mounted cargo handling platform lifting device that can be easily installed on a vehicle, does not need periodic maintenance work such as oil change, and can be used for an application in which oil leakage becomes problematic.SOLUTION: The vehicle-mounted cargo handling platform lifting device includes a pair of vertical outer columns fixed to a load-carrying platform, a connection frame fixed in a direction orthogonal to the outer columns, an electric cylinder 40 provided in the connection frame, and a cargo handling platform capable of ascending and descending along the pair of the outer columns. The electric cylinder 40 includes a ball screw shaft 42 that penetrates a rotor 43b of a motor 43, and a nut 45 screwed to the ball screw shaft 42 and rotationally driven by the motor 43. The electric cylinder 40 and the cargo handling platform are connected to each other, and by a telescopic operation of the electric cylinder 40, the cargo handling platform is driven so as to ascend and descend along the pair of the outer columns.

Description

  The present invention relates to an on-vehicle cargo handling platform lifting apparatus using an electric cylinder.

  Conventionally, in-car loading / unloading devices are generally hydraulic, and the hydraulic cylinder that drives the loading / unloading platform and the hydraulic power source (power unit) are separate parts (separately procured). The mainstream is a structure that is built into the equipment and the hydraulic power source is suspended on the vehicle side on which the loading / unloading equipment is mounted in consideration of maintenance. Since installation of the cargo handling platform lifting device on the vehicle requires hydraulic piping, electrical wiring, and the like, the current situation is that work is being carried out under complicated circumstances in a small space.

  In order to improve the problem relating to the installation of such a cargo handling platform lifting device, a proposal to solve by integrating the hydraulic cylinder and the hydraulic power source into the cargo handling platform lifting device is made in the following Patent Document 1. ing. However, it is assumed that maintainability such as oil exchange becomes more difficult than before.

JP 2009-269595 A

  As described above, in order to raise and lower the cargo handling platform of the cargo handling platform elevating device, the construction using the hydraulic cylinder and the hydraulic source arranged separately from this causes complicated operations such as hydraulic piping and electrical wiring when mounted on the vehicle. In addition, when the hydraulic cylinder and the hydraulic source are integrated into the apparatus, there is a problem that maintenance becomes difficult. Further, when a hydraulic cylinder is used, the problem of oil leakage is likely to occur, and there is a problem in using it for applications where oil leakage is not allowed.

  The present invention has been made in view of this situation, and its purpose is that it can be easily installed in a vehicle, does not require regular maintenance such as oil change, and can be used for applications where oil leakage is a problem. An object of the present invention is to provide an on-vehicle cargo handling platform lifting device.

One embodiment of the present invention is an on-vehicle cargo handling platform lifting device. The vehicle loading / unloading platform lifting device includes a pair of outer columns that are fixed to a chassis frame or a loading platform mounted on the chassis frame, and a connection frame that is fixed in a direction perpendicular to the pair of outer columns. And an electric cylinder provided in the connection frame, and a cargo handling platform that can be moved up and down along the pair of outer columns,
The electric cylinder has a stator and a motor having a rotor that rotates inside the stator, a screw shaft that passes through the rotor, and a nut that is screwed into the screw shaft and is rotationally driven by the motor. One end of the screw shaft is one connection end of the electric cylinder, the stator side is the other connection end of the electric cylinder,
The electric cylinder and the cargo handling table are connected to each other, and the cargo handling table is driven up and down along the pair of outer columns by an expansion and contraction operation of the electric cylinder.

  In the above aspect, a speed reduction mechanism is provided between the rotor and the nut.

  In the above aspect, the motor is a brushless motor.

  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, systems, and the like are also effective as an aspect of the present invention.

  According to the present invention, the problem caused by using a hydraulic cylinder can be solved by using an electric cylinder having a structure in which a screw shaft passes through a rotor of a motor as a drive source for raising and lowering a cargo handling platform. That is, it becomes easy to install the load receiving platform elevating device on the vehicle, and regular maintenance such as oil replacement is unnecessary, and oil leakage can be eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS The side view which made the cross section the part which shows embodiment of the vehicle-mounted cargo handling platform raising / lowering apparatus which concerns on this invention. Similarly perspective view. The perspective view of the electric cylinder used in this Embodiment. Sectional drawing of the principal part of an electric cylinder.

  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.

  An embodiment of an on-board cargo handling platform lifting / lowering device according to the present invention will be described with reference to FIGS. 1 to 4. In these drawings, a rear loading platform 2 is mounted on a chassis frame 1 of a cargo handling vehicle, and a vehicle loading platform lifting device 10 is provided at the rear end of the loading platform 2. The loading / unloading platform lifting device 10 lifts and lowers the loading platform 11 held substantially horizontally between the ground and the floor surface of the loading platform 2, and loads the load placed on the loading platform 11 between the ground and the loading platform 2. Can be taken down.

  A pair of left and right outer columns 12 extending in the vertical direction are fixed to the left and right side edges of the rear end portion of the loading platform 2. Each outer column 12 is formed of a hollow rectangular tube. A pair of left and right inner columns 13 are inserted into the pair of outer columns 12 so as to be movable up and down. Each inner column 13 is constituted by a hollow rectangular tube. The outer column 12 is rotatably provided with a guide roller 15 for guiding the raising and lowering of the inner column 13. A guide roller 18 is pivotally supported on the upper end of the inner column 13 via a bracket to guide the raising and lowering of the inner column 13 in the outer column 12.

  Sliders 14 are inserted into the pair of inner columns 13 so as to be movable up and down. The rear edges of the sliders 14 pass through the vertical slits 13a and 12a formed in the inner column 13 and the outer column 12, respectively. It is possible to move up and down with respect to the outer column 12 and the inner column 13 by being guided by the vertical slits 13a and 12a.

  Upper and lower guide rollers 25, 26 are rotatably supported on the upper and lower portions of the slider 14, and when the slider 14 moves up and down with respect to the inner column 13, these guide rollers 25, 26 are supported by the inner column 13. Roll on the inside. Brackets 28 are fixed to the lower ends of the outer surfaces of the pair of sliders 14, and pins 29 are attached to these brackets 28 so that the cargo handling platform 11 can rotate between a substantially horizontal deployment position and a substantially vertical storage position. It is pivotally attached.

  A connecting frame 30 that extends in the horizontal direction at a position substantially coincident with the floor surface of the loading platform 2 is fixed in a substantially horizontal direction (a direction orthogonal to the outer column 12) at an intermediate portion in the vertical direction of the pair of outer columns 12. Yes. The connection frame 30 is a hollow rectangular tube body in which a cover body is attached to an opening surface of a connection frame body having a U-shaped cross section, and an electric cylinder 40 is provided inside the connection frame 30 (electric cylinder). 40 will be described in detail in FIGS. 3 and 4).

  The main body side attachment end 41 of the electric cylinder 40 is pinned to the frame 30 in the connecting frame 30. The cargo handling platform 11 is interlocked and coupled to the electric cylinder 40 through a wire interlocking mechanism provided across the pair of outer columns 12 and the coupling frame 30, and is lifted and controlled by the expansion and contraction operation of the electric cylinder 40. It has become. The configuration of the wire interlocking mechanism will be described below.

  The tip of the ball screw shaft 42 (FIG. 3) of the electric cylinder 40 extends partway through the connection frame 30 and is connected and fixed to the bracket 60. A plurality of sheaves 61 are rotatably mounted in parallel on the bracket 60, and the bracket 60 is slidably supported in the connecting frame 30. In FIG. 2, a plurality of fixed sheaves 62 are rotatably mounted in parallel on the left end of the connection frame 30. Here, the number of the sheaves 61, 62 around which the wire 71 having the end fixed to the left slider 14 is wound is one by one, and the sheave 61, the wire 72 having the end fixed to the right slider 14 is wound around. There are also 62 pieces each.

  The electric cylinder 40 is connected with two wires 71 and 72 on the left and right sides. That is, one end of the left wire 71 is connected to the intermediate portion 71a of the connecting frame 30 and extends along the connecting frame 30. The wire 71 is wound between the sheave 6l and the sheave 62, and further, the left outer column 12 is connected. It is wound around a top sheave 36 pivotally supported at the upper end, and the other end is bound to the left slider 14. Similarly, one end of the right-system wire 72 is attached to the intermediate portion 72a of the connecting frame 30 and extends along the connecting frame 30. The wire 72 is wound between the sheave 61 and the sheave 62, and further on the right side of the connecting frame 30. The other end of the right outer column 12 is bound to the slider 14 on the right side.

  Accordingly, when the electric cylinder 40 is extended and contracted, the pair of left and right sliders 14 are moved up and down synchronously via the two systems of wires 71 and 72, and the cargo handling table 11 connected thereto can be driven up and down.

  As shown in FIGS. 3 and 4, the electric cylinder 40 includes a hollow shaft brushless motor 43, a speed reduction mechanism 44, a ball screw shaft 42 penetrating them, and a ball screw nut 45 screwed into the ball screw shaft 42. Have. The casing 46 of the brushless motor 43, the casing 47 of the speed reduction mechanism 44, and the casing 48 of the ball screw nut 45 are integrated with each other by bolts or the like.

  The brushless motor 43 includes a stator 43a fixed to the casing 46 and a rotor 43b rotatably held by the casing 46, and the ball screw shaft 42 passes through the casing 46 and the rotor 43b. The speed reduction mechanism 44 is, for example, a swing speed reduction mechanism, a planetary gear mechanism, a harmonic gear, and the like, and is housed inside the casing 47 and includes an input member 44a and an output member 44b that decelerates and outputs the rotation of the input member 44a. ing. The input member 44a is connected and integrated with the rotor 43b, and the output member 44b is connected and integrated with the ball screw nut 45. The ball screw nut 45 is rotatably supported in the casing 48 by a bearing 49. However, the ball screw nut 45 and the casing 48 move together in the axial direction of the ball screw shaft 42. An extension casing 50 that houses the retractable ball screw shaft 42 is connected and fixed to the casing 46 of the brushless motor 43. An end portion of the extension casing 50 is a main body side attachment end portion 41. Further, as described above, the bracket 60 for holding the sheave 61 is fixed to the tip of the ball screw nut 42.

  In the configuration of the electric cylinder 40 described above, when the brushless motor 43 is energized to rotate the rotor 43b, the rotation is transmitted to the ball screw nut 45 via the speed reduction mechanism 44, and the ball screw nut 42 is moved to the ball screw shaft 42. 45 is rotated. As a result, the ball screw nut 45 moves in the axial direction of the ball screw shaft 42. As a result, the casings 46, 47, 48, and 50 are moved together to expand and contract the electric cylinder 40.

  The overall operation of the vehicle loading / unloading table lifting apparatus 10 will be described. When the electric cylinder 40 is contracted, the distance between the sheave 61 and the sheave 62 is reduced, and the two wires 71 and 72 wound around the sheaves are fed out. The slider 14 descends, and as a result, the cargo handling platform 11 is landed. On the contrary, when the electric cylinder 40 is extended, the interval between the sheave 6l and the sheave 62 is increased, so that the two systems of wires 71 and 72 wound between the sheaves are wound up. (The inner column 13 is pulled up when the stopper 27 at the upper end of the slider 14 hits the ceiling surface of the inner column 13). As a result, the cargo handling platform 11 is pulled up to the same height as the floor surface of the loading platform 2.

  According to the present embodiment, the following effects can be achieved.

(1) By using the electric cylinder 40 having a structure in which the ball screw shaft 42 penetrates the rotor 43b of the brushless motor 43 as a driving source for raising and lowering the cargo handling platform 2, problems caused by using a hydraulic cylinder can be solved. it can. That is, the loading / unloading platform lifting / lowering device 10 can be easily installed on the vehicle, and regular maintenance such as oil replacement is unnecessary, and oil leakage can be eliminated.

(2) In a general electric cylinder, the motor is driven to rotate from the outside by a nut that is screwed onto the ball screw shaft, so that the motor part protrudes greatly to the side. For this reason, it becomes difficult to store the electric cylinder in the connecting frame 30, but in this embodiment, by using the electric cylinder 40 having a structure in which the ball screw shaft 42 penetrates the rotor 43 b of the brushless motor 43, There is no protrusion of the motor 43 to the side, and the outer shape can be similar to that of a conventional hydraulic cylinder, and the cross section of the connecting frame 30 can be small. As a result, it can be applied to various vehicles.

  The present invention has been described above by taking the embodiment as an example. However, it is understood by those skilled in the art that various modifications can be made to each component and each processing process of the embodiment within the scope of the claims. By the way. Hereinafter, modifications will be described.

  The pair of outer columns 12 may be fixed to the rear end portion of the chassis frame 1 via a frame or the like instead of being fixed to the loading platform 2.

DESCRIPTION OF SYMBOLS 1 Chassis frame 2 Loading platform 10 Cargo loading platform raising / lowering device 11 Loading platform 12 Outer column 13 Inner column 14 Slider 15, 18, 25, 26 Guide roller 28, 60 Bracket 30 Connecting frame 35, 36, 37, 61, 62 Sheave 40 Electric cylinder 41 Body side attachment end 42 Ball screw shaft 43 Brushless motor 44 Reduction mechanism 45 Ball screw nuts 71 and 72 Wire

Claims (3)

A pair of vertically extending outer columns fixed to the chassis frame or a loading platform mounted on the chassis frame;
A connecting frame fixed in a direction orthogonal to the pair of outer columns;
An electric cylinder provided in the connecting frame;
A loading platform that can be raised and lowered along the pair of outer columns,
The electric cylinder has a stator and a motor having a rotor that rotates inside the stator, a screw shaft that passes through the rotor, and a nut that is screwed into the screw shaft and is rotationally driven by the motor. One end of the screw shaft is one connection end of the electric cylinder, the stator side is the other connection end of the electric cylinder,
An in-vehicle loading / unloading platform lifting apparatus, wherein the electric cylinder and the loading / unloading base are connected, and the loading / unloading drive is driven up and down along the pair of outer columns by an expansion / contraction operation of the electric cylinder.   The on-vehicle cargo handling platform elevating device according to claim 1, wherein a speed reduction mechanism is provided between the rotor and the nut.   The in-vehicle cargo handling platform elevating device according to claim 1 or 2, wherein the motor is a brushless motor.

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