JP2004051211A - General-purpose pallet and work feed line - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pallet which can be easily matched with the shape of a work (various parts for a car body, an engine or the like) even when the shape of the work to be mounted is different in each model. <P>SOLUTION: The pallet 1 placed on a conveyor which runs along a circulating work feeding line comprises a frame part 1a composing the outside and a work mount part 1b placed in the frame part 1a and the work mount part 1b is made of an impression material. In order from the upper stream along the work feeding line, a heating storage 2 to soften the impression material, a standard shape transferring part 3 to form the impression material in a standard shape, a work shape transferring part 4 to transfer the shape of the work to be mounted in the impression material, a cooling storage 5 to harden the impression material and a loading part 6 to transfer the work on the pallet are arranged. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a general-purpose pallet for mounting various parts (work) such as a vehicle body, a fuel tank, and an engine, and a work transfer line incorporating the general-purpose pallet.
[0002]
[Prior art]
In order to improve production efficiency, multi-model mixed production lines are used in automobile production lines. In this multi-model mixed production line, it is necessary to assemble a wide variety of parts for the same part, depending on the model, and pallets for placing and transporting these parts require many types of pallets according to the part shape. Become.
[0003]
If many types of pallets are prepared, not only is the production of pallets troublesome and costly, but also a place to store pallets when not in use must be secured. The pallet must be discarded or the mounting section must be replaced for a new model, but it is time-consuming.
[0004]
Therefore, proposals for performing conveyance or the like in accordance with the shape of a work are disclosed in JP-A-2-303771, JP-A-3-118868, JP-A-3-200610, and JP-A-2000-263488. .
[0005]
In Japanese Patent Application Laid-Open No. Hei 2-33071, a receiving portion made of a large number of metal rods is arranged in a frame, and these receiving portions can be moved up and down and fixed at a predetermined position by magnetic force or the like. From the receiving part.
In Japanese Utility Model Laid-Open Publication No. 3-118868, a large number of pins urged upward by a spring are arranged on a support portion of a transport hanger of a vehicle body, and only a predetermined pin out of the multiple pins is pushed in accordance with the shape of the vehicle body. I have to.
In Japanese Patent Application Laid-Open No. 3-200610, a plurality of fingers for gripping a work are provided on a transfer bar, and the base of the finger is deformed by temperature so that each finger is bent according to the shape of the work.
In Japanese Patent Application Laid-Open No. 2000-263488, a shape memory polymer is used as a material of a portion of a hand portion of a transfer device that grips a work, and a workpiece is gripped with a shape memory polymer in a softened state by blowing hot air with an industrial dryer. This shape is maintained by cooling the shape memory polymer.
[0006]
[Problems to be solved by the invention]
Among the prior arts described above, in a configuration using a large number of pins (rods) as disclosed in JP-A-2-303771 and JP-A-3-118868, a large-scale apparatus is required, and a work is caused by a tip of the pin. If the weight of the work is large, there is a possibility that the resilience of the spring urging the pin is reduced during many uses.
[0007]
In the prior art disclosed in Japanese Patent Application Laid-Open No. 3-200610, the shape of the tip of the finger is not changed in accordance with the shape of the work, so that it cannot cope with a work having a complicated shape and is difficult to apply to a pallet. is there.
[0008]
The prior art disclosed in Japanese Patent Application Laid-Open No. 2000-263488 is applied to a pallet for continuously transporting a large number of components, in order to deform the shape of the gripping portion, each time an industrial dryer must blow hot air. I can't.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a general-purpose pallet according to the present invention includes a frame body and a work mounting portion, and softens the work mounting portion at a predetermined temperature higher than a normal work transfer temperature, and performs normal work transfer. It was formed from an impression material that maintained a cured state at a temperature.
With such a configuration, the work mounting portion can be easily adapted to the shape of the work.
[0010]
Also, the work transfer line according to the present invention incorporating the above-mentioned general-purpose pallet, a heating storage for softening the impression material of the general-purpose pallet is arranged on the upstream side of the work transfer line, and the downstream side of the heating storage along the work transfer line. A cooling storage that arranges a work shape transfer unit that transfers the work shape placed on the impression material and hardens the impression material at the same position as this work shape transfer unit or at the downstream side along the work transfer line of the work shape transfer unit And a work placement part on a pallet was arranged downstream of the cooling storage along the work transfer line.
With the above configuration, many works having different shapes can be continuously conveyed using one type of pallet.
In particular, a circulation type line is effective as a work transfer line to which the general-purpose pallet according to the present invention is applied.
[0011]
Further, a configuration may be adopted in which a reference shape transfer unit that makes the impression material a reference shape is disposed between the heating storage and the work shape transfer unit. In this way, even if the model is changed during the transfer, the general-purpose pallet can be continuously sent to the work mounting position without stopping the line.
[0012]
Further, as the heating means in the heating storage, far infrared rays used in a microwave oven or the like are preferable because the impression material can be uniformly heated to the inside in a short time.
Further, by adding a heating mechanism to the mold forming the reference shape transfer section, the work shape transfer in the work shape transfer section can be smoothly performed, and cooling to the mold forming the work shape transfer section can be performed. By adding a mechanism, it is possible to prevent sagging of the impression material after molding.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is an overall view of a work transfer line incorporating a general-purpose pallet according to the present invention. The work transfer line is of a circulating type, and a pallet 1 is placed on a conveyor running along the line.
[0014]
The pallet 1 is composed of a frame 1a constituting the outside and a work placing portion 1b provided in the frame 1a, and the work placing portion 1b is made of an impression material. This impression material (trade name: Impression Tray Compound: manufactured by GC Co., Ltd.) contains Copal C (natural resin (hemifossil resin)), talc, stearin (oil and fat), iron oxide, and the like as main components.
[0015]
FIG. 2 shows the relationship between the temperature of the impression material and the compression ratio. As is clear from this graph, when the temperature exceeds 50 ° C., the material gradually softens, and at 65 ° C., the compression ratio reaches about 60%. Therefore, it can be seen that this impression material can be changed into an arbitrary shape by heating to about 65 ° C., and is cured by cooling to about 40 ° C.
[0016]
A heating storage 2 for softening the impression material, a reference shape transfer unit 3 for making the impression material a reference shape, a work shape transfer unit 4 for transferring the work shape placed on the impression material, in order from the upstream side along the work transfer line, A cooling storage 5 for curing the impression material and a loading unit 6 for transferring the work to a pallet are arranged.
[0017]
The heating storage 2 is provided with a far-infrared ray generating device, and the impression material is softened by heating to a uniform temperature (about 65 ° C.) not only on the surface of the impression material but also on the inside.
[0018]
In the reference shape transfer unit 3, as shown in FIG. 3, the mold 31 is pressed against the impression material by the cylinder unit 32 to form a reference shape. In this embodiment, the reference shape is an inverted trapezoidal shape (a truncated pyramid shape).
When the mold 31 is pressed against the impression material to form a reference shape, if the mold 31 is at room temperature, the surface of the impression material after molding is cooled and hardened, and the work shape is transferred to the next work shape transfer unit. The mold 31 is provided with a supply pipe 33 and a discharge pipe 34 for the heating medium in the mold 31, and the surface of the mold 31 is heated to a uniform temperature (65 ° C.) so that the surface of the impression material after molding is reduced. Cooling and hardening can be prevented.
However, a work shape transfer unit 4 is provided immediately downstream of the reference shape transfer unit 3, and when the work transfer line is operated to some extent and the reference shape transfer unit 3 is operated a plurality of times, the temperature of the mold 31 increases. Therefore, it is not always necessary to heat the mold 31.
[0019]
In the work shape transfer unit 4, as shown in FIG. 4, the mold 41 is pressed against the impression material by the cylinder unit 42 to transfer the work shape. In the illustrated example, since the fuel tank is shown as the work, the lower surface shape of the mold 41 is made equal to the lower surface shape of the fuel tank.
The mold 41 of the work shape transfer unit 4 also has a supply pipe 43 and a discharge pipe 44 for the cooling medium, similarly to the mold 31.
[0020]
As shown in FIG. 5, the work W is transferred to the work mounting portion 1b in which the concave portion corresponding to the work shape is formed, as shown in FIG. 5, and the work transfer line is transferred in this state. In the meantime, a predetermined operation is performed on the work W.
[0021]
In the illustrated example, the work shape transfer unit and the cooling storage are provided at different locations. However, the work shape transfer unit is arranged in the cooling storage, and the transfer of the work shape and the maintenance of the shape by cooling are performed simultaneously in parallel. You may.
[0022]
When the shape of the work is simple, the work shape may be directly transferred to the impression material coming out of the heating storage 2 without providing the reference shape transfer unit 3.
[0023]
Further, when a large number of the same works are transferred on the work transfer line, it is not necessary to change the shape of the mounting portion. In such a case, running the pallet in the path from the heating storage to the cooling storage is useless. Therefore, in order to cope with such a case, a bypass line is provided along the main line of the work transfer line, and a heating storage 2, a reference shape transfer unit 3 for making the impression material a reference shape, and a bypass line are mounted on the bypass material. A work shape transfer unit 4 for transferring a work shape to be placed and a cooling storage 5 for hardening an impression material may be arranged.
[0024]
【The invention's effect】
As described above, according to the present invention, the work placement on the pallet for transferring the work is softened at a predetermined temperature higher than the normal work transfer temperature, and the cured state is maintained at the normal work transfer temperature. Since it is made of a material, one type of pallet can be used for workpieces of any shape, and there is no need to prepare many types of pallets or secure the standby space for unused pallets. There is no risk of damaging the work as compared with the prior art using pins.
[0025]
Further, according to the work transfer line incorporating the general-purpose pallet according to the present invention, compared with the prior art in which the shape memory polymer is provided in the grip portion of the hand, it is possible to continuously transfer many works having different shapes. It is suitable for a mixed production line of automobiles.
[Brief description of the drawings]
FIG. 1 is an overall view of a work transfer line incorporating a general-purpose pallet according to the present invention. FIG. 2 is a graph showing a relationship between an impression material temperature and a pressure reduction ratio. FIG. FIG. 4 is a cross-sectional view of a general-purpose pallet showing a state in which a mounting shape is formed into a reference shape in a work shape transfer unit. Cross-sectional view of a general-purpose pallet in a broken state [Description of symbols]
DESCRIPTION OF SYMBOLS 1 ... Pallet, 1a ... Frame, 1b ... Work placement part, 2 ... Heating storage, 3 ... Reference shape transfer part, 4 ... Work shape transfer part, 5 ... Cooling storage, 6 ... Work loading part, 31, 41 ... Mold, 32, 42: Cylinder unit, 33: Heating medium supply pipe, 34: Heating medium discharge pipe, 43: Cooling medium supply pipe, 44: Cooling medium discharge pipe, W: Work.

Claims (6)

A general-purpose pallet comprising a frame and a work placement part, wherein the work placement part is softened at a predetermined temperature higher than a normal work transfer temperature and maintains a hardened state at a normal work transfer temperature. A general-purpose pallet characterized by being formed with: In the work transfer line using the general-purpose pallet according to claim 1, a heating storage for softening an impression material of the general-purpose pallet is arranged on an upstream side of the work transfer line, and on a downstream side of the heating storage along the work transfer line. A work shape transfer unit that transfers the work shape placed on the impression material is arranged, and a cooling storage that hardens the impression material at the same position as this work shape transfer unit or downstream along the work transfer line of the work shape transfer unit is provided. A work transfer line, wherein a work placement portion on a pallet is disposed downstream of the cooling storage along the work transfer line. 3. The work transfer line according to claim 2, wherein a reference shape transfer unit that makes the impression material a reference shape is disposed between the heating storage and the work shape transfer unit. 4. The work transfer line according to claim 2, wherein the transfer line is a circulation line. 5. The work transfer line according to claim 2, wherein the heating means in the heating storage is a far-infrared ray. 6. The work transfer line according to claim 2, wherein a heating mechanism is added to the mold forming the reference shape transfer unit, and a cooling mechanism is added to the mold forming the work shape transfer unit. A work transfer line characterized by the following.

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