JP5593059B2 - lift device - Google Patents

Description

  The present invention relates to an elevating device that is mounted on the rear part of a vehicle such as a lorry and driven by a parallel link mechanism to facilitate loading and unloading of cargo, and more particularly to an arm structure of a parallel link mechanism.

  2. Description of the Related Art Conventionally, as a lifting device to be mounted on a truck, one that lifts a platform with a parallel link mechanism is known. One example of such a lifting device is described in Patent Document 1 below.

JP 2007-106142 A

  Conventionally, the main arm that constitutes one of the parallel links for driving the platform up and down supports a pair of arm plates at an interval using a jig, and a spacer is arranged inside the pair of arm plates. Thus, the arm plate and the spacer are connected and integrated by welding work inside the pair of arm plates.

  In this case, welding work is required on the inside of the pair of arm plates (the inside of the narrow gap where the arm plates face each other), the workability of welding is poor, the position of the spacer is shifted during welding, and the arm is accompanied by welding. There is a problem that distortion occurs in the plate.

  The present invention has been made in view of such a situation, and its purpose is to make it easy to perform assembly work by welding arms of a parallel link mechanism for raising and lowering the raising and lowering platform, and to realize a robust arm structure. To provide an apparatus.

An aspect of the present invention is an elevating device, comprising a main body frame provided on the vehicle side, and an elevating platform that is driven up and down via a parallel link mechanism with respect to the main body frame,
At least one of the arms of the parallel link mechanism includes a pair of arm plates facing each other,
A plurality of spacer plates provided between the pair of arm plates;
The plurality of spacer plates have convex pieces that fit into the through holes of the pair of arm plates, respectively, and any one of the spacer plates has a bent portion along the edge of the arm plate,
The convex piece portion is fitted into the through hole to form a fitting structure in which the plurality of spacer plates are arranged between the pair of arm plates, and the plurality of spacer plates are welded and integrated with the arm plate. It is said.

In the above aspect , the height of the convex piece portion may be shorter than the depth of the through hole, and the convex piece portion may be welded to the inner wall of the through hole.

  In the above aspect, the height of the convex piece portion may be equal to or greater than the depth of the through hole, and the convex piece portion may be welded around the through hole.

  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 present invention, in the lifting device that drives the lifting platform up and down via the parallel link mechanism, the assembly work by welding the arms constituting the parallel link can be facilitated, and a robust arm structure can be realized.

1 is a plan view showing a configuration in which left and right main arms are connected, which is an embodiment of a lifting device according to the present invention. It is the same front view. It is the same side view. It is IV-IV expanded sectional drawing of FIG. FIG. 6 is an enlarged plan view of a spacer plate for connecting arm plates to each other in the main arm. In the main arm, it is another spacer plate for connecting arm plates, (A) is an enlarged plan view, (B) is an enlarged front view. It is a front view which shows the whole structure of embodiment of the raising / lowering apparatus which concerns on this invention. It is an expanded sectional view which shows the principal part structure of other embodiment of the raising / lowering apparatus which concerns on this invention.

  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 6 show the structure of the main arm used in the embodiment of the lifting device according to the present invention, and FIG. 7 shows the overall configuration of the embodiment of the present invention.

  First, the overall configuration of the lifting device of FIG. 7 will be described. A box-shaped vehicle body 2 is mounted and fixed on a chassis 1 of a truck, and a body frame 10 of the lifting device is connected to a cargo via an attachment member 4. It is fixed to the rear part of the chassis 1 of the automobile. The main body frame 10 includes a square pipe 11 as a connecting member and brackets 12 and 13 fixed to both sides thereof.

  The elevating platform 60 is driven up and down by a parallel link mechanism. That is, the base end portions of the main arm 20 and the sub arm 30 forming a parallel link are pivotally attached (rotatably attached) to the brackets 12 and 13 by the pins 21 and 31, and the distal end portions are pin 22 to the bracket 61 on the lifting platform 60 side. , 32. Further, an elevating hydraulic cylinder 27 is pivotally attached by pins 28 and 29 between the lower portion of the bracket 12 and a position near the tip of the main arm 20.

  The pins 21 and 22 at both ends of the main arm 20 and the pins 31 and 32 at both ends of the sub arm 30 which are one link of the lifting drive link mechanism are respectively located at the apexes of the parallelogram, and the lifting platform 60 is in a horizontal state. Is maintained and maintained. When the elevating hydraulic cylinder 27 is contracted, the tip of the main arm 20 is lowered (the lowered position where the platform 60 is lowered), and when extended, the tip of the main arm 20 is raised (the platform 60 is the same as the floor surface 3). Height rise position).

  As shown in FIGS. 1 to 6, the main arm 20 has a pair of arm plates 40 facing each other, spacer plates 51, 52, 53, 54 provided between the pair of arm plates 40, and a pin 21 passing therethrough. And a bearing portion 56 through which the pin 22 penetrates, and these are integrated by welding.

  As shown in FIG. 5, the spacer plate 51 has convex pieces 51 a that fit into the rectangular through holes 41 of the arm plate 40 on both edges. Similarly, the spacer plate 52 has convex piece portions 52a that fit into the through holes 41 of the arm plate 40 on both edges as shown in FIGS. 6 (A) and 6 (B). The same applies to the other spacer plates 53 and 54. As shown in FIG. 4, the height T of each convex piece is shorter than the depth D of the through hole 41 and may be set to about 1/3 to 1/2 of the depth D of the through hole 41. preferable.

  Then, the convex pieces 51 a to 54 a on one edge of the spacer plates 51 to 54 are fitted into the through holes 41 of the one arm plate 40, and the convex pieces 51 a to 54 a on the other edge are fitted to the other arm plate 40. The projections 51 a to 54 a and the arm plate 40 are integrated by welding in the through holes 41 and inside the through holes 41. That is, since the height of each convex piece part 51 a to 54 a is shorter than the depth of the through hole 41, the convex piece parts 51 a to 54 a are welded to the inner wall of the through hole 41. In addition, when the height of each convex piece part 51a-54a is larger than 1/2 of the depth of the through-hole 41, the ratio which the welding part W protrudes from the through-hole 41 will become large, and the depth of the through-hole 41 is 1 If it is less than / 3, the fitting length of the convex piece portion into the through hole 41 becomes short.

  A bearing portion 55 is fixed to the base end side of the arm plate 40, and a bearing portion 56 is fixed to the distal end side by welding to form the main arm 20, and left and right main arms that are positioned on both sides of the vehicle chassis. A connecting pipe 58 is fixed between the two by welding.

  Each arm plate 40 is formed with a through hole 45 through which a pin 29 for connecting one end of the lifting hydraulic cylinder 27 passes, and a reinforcing plate 46 is fixed around the through hole 45.

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

(1) In the lifting device that drives the lifting platform 60 up and down via the parallel link mechanism, assembly work by welding the main arm 20 constituting one of the parallel links can be facilitated, and a robust arm structure can be realized. .

(2) That is, the main arm 20 is a combination of a fitting structure of a pair of arm plates 40 and spacer plates 51, 52, 53, and 54 provided therebetween, and a welding structure. It is possible to increase the mechanical strength as compared with a conventional main arm structure which is not formed.

(3) Further, the welding work can be performed from the outside of the arm plate 40 in a state where the pair of arm plates 40 and the spacer plates 51, 52, 53, 54 are fitted, and workability can be improved. is there. Further, since some of the spacer plates are bent, the spacer plates are in a self-supporting state with respect to the horizontally arranged main arm 20, so that no assembly jig is required.

  FIG. 8 is an enlarged cross-sectional view showing the main configuration of another embodiment of the lifting device according to the present invention. The height of each convex piece portion 51 a formed on the spacer plate 51 or the like is the height of the through hole 41. The convex piece 51a is welded around the through hole 41, which is larger than the depth. Thereby, the arm plate 40 and the spacer plate 51 are integrated by welding. Other configurations are the same as those in the first embodiment.

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

  In addition, the raising / lowering apparatus which can apply this invention should just drive an raising / lowering platform by the parallel link mechanism shown in FIG. In addition to the main arm forming one link of the parallel link mechanism, the sub-arm forming the other link can also adopt the same structure as the main arm.

  The present invention can also be applied to a floor-retractable lifting device in which the vehicle body frame is slidable with respect to the vehicle (can be retracted under the floor) and the lifting platform is foldable.

DESCRIPTION OF SYMBOLS 1 Chassis 2 Car body 3 Floor surface 10 Main body frame 12,13,61 Bracket 20 Main arm 21,22,31,32 Pin 30 Sub arm 40 Arm plate 41 Rectangular through hole 45 Through hole 46 Reinforcement plates 51-54 Spacer plates 51a-54a Convex piece 55, 56 Bearing 58 Connection pipe

Claims (3)

A main body frame provided on the vehicle side, and an elevating platform that is driven up and down via a parallel link mechanism with respect to the main body frame,
At least one of the arms of the parallel link mechanism includes a pair of arm plates facing each other,
A plurality of spacer plates provided between the pair of arm plates;
The plurality of spacer plates have convex pieces that fit into the through holes of the pair of arm plates, respectively, and any one of the spacer plates has a bent portion along the edge of the arm plate,
A lifting device in which the convex piece portion is fitted into the through-hole and the plurality of spacer plates are arranged between the pair of arm plates, and the plurality of spacer plates are welded and integrated with the arm plate. . The elevating device according to claim 1 , wherein the height of the convex piece portion is shorter than the depth of the through hole, and the convex piece portion is welded to the inner wall of the through hole. 2. The lifting device according to claim 1 , wherein the height of the convex piece portion is equal to or greater than the depth of the through hole, and the convex piece portion is welded around the through hole.

Images