JP2003053630A - Positioning device of pallet-type carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positioning device capable of absorbing errors in the stop position not only in the pallet carrying direction but also in the direction orthogonal thereto. SOLUTION: A supporting frame 5 is mounted on a base frame 4 via a linear guide 15, and a plurality of pallet carrying drive rollers 6 rotated by a motor 8 are provided on the supporting frame 5. A pallet 1 is pulled onto the supporting frame 5 while the sliding degree of freedom of the linear guide 15 is restricted by a lock pin 17. A positioning pin 12 is elevated to position the pallet 1 while unlocking the lock pin 17 with the sliding degree of freedom. Errors in the stop position in the pallet carrying direction and the direction orthogonal thereto can be absorbed by the sliding degree of freedom of the linear guide 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning device for a pallet type conveying device, and more particularly to a positioning device for a pallet type conveying device suitable for use as a vehicle body assembly facility for automobiles.

[0002]

2. Description of the Related Art As a pallet type transfer apparatus of this type, as shown in FIG. 4, a pallet positioning stage S1 is made of urethane which is forcibly rotated by a motor 52 when the pallet 50 is carried in and out of a pallet carrying surface of a support frame 51. There are a plurality of drive rollers 53 provided. It should be noted that the drive rollers 53 are simultaneously rotated in synchronization via a winding transmission means 54 such as a chain.

Then, the transfer level of the pallet 50 is H1.
, And the positioning level thereof is set to the height position of H2, respectively, and when the pallet 50 with the work loaded state conveyed from the previous process is carried in, it is driven by the drive force of the drive roller 53. The pallet 50 is drawn onto the support frame 51, and the pallet 50 is lifted down to the positioning level H2 together with the support frame 51 by the lift cylinder 64 and fitted to the fixed positioning pin 55. Is separated from the support frame and positioned on the positioning stage S1 (similar structure is described, for example, in Japanese Patent Application No. 2001-79735 of the present applicant). The support frame 51 is guided and supported so as to be able to move up and down by a guide mechanism 57 provided upright on the base 56.

Here, the pallet 50 is a support frame 51.
The brake attached to the motor 52 is released after the support frame 51 is lifted down after being carried up. By doing so, the individual drive rollers 53 are brought into a non-braking state, for example, the pallet 5
Even when 0 is slightly deviated from the normal position in the traveling direction and stopped, the pallet 50 slightly moves together with the drive roller 53 by following the fitting operation of the positioning pin 55 and the positioning hole on the mating side. The positional deviation in the pallet conveying direction can be absorbed.

[0005]

However, in the above-mentioned structure, even if the stop position error in the pallet conveying direction can be absorbed, the function of absorbing the stop position error in the width direction of the pallet 50 is absorbed. For example, if the positioning pin 55 performs positioning with a stop position error in the width direction, the drive rollers 53 do not have such a position.
A large force that can overcome the frictional force between the pallet 50 and the pallet 50 is applied to the positioning pin 55, and the positioning pin 55 is likely to be damaged.

Moreover, since the pallet 50, which is a heavy object, is moved up and down together with the support frame 51, the lift cylinder 64 and the guide mechanism 57 having a large capacity.
Is required, the entire facility becomes large and expensive, and a pit is required, which is not preferable.

The present invention has been made by paying attention to the above problems, and it is possible to absorb the stop position error in the width direction of the pallet so as to reduce the external force load applied to the positioning pin, and further to make a large-scale lift. An object of the present invention is to provide a positioning device for a pallet type transfer device that does not require a cylinder or a guide mechanism.

[0008]

According to a first aspect of the present invention, a pallet positioning stage is provided with a support frame for supporting the pallet, and the pallet transport surface of the support frame is used for loading and unloading the pallet. A plurality of drive rollers that are driven to rotate by force are provided, and the pallet loaded from the previous process is pulled into the support frame by the drive force of the drive roller, and then this pallet is fitted to the positioning pin to become the pallet positioning stage. It is premised that the device is a positioning device for a pallet type transfer device which is positioned.

The support frame is slidably mounted on a fixed-position fixed base frame of the pallet positioning stage through a direct-acting guide member in a direction orthogonal to the pallet conveying direction, and the pallet is mounted on the base frame. Providing a retractable positioning pin that fits partly and positions it, and further, in either one of the base frame and the support frame, except for the positioning operation of the pallet by the positioning pin, It is characterized in that lock means is provided which is fitted to the other member of the frame and the support frame to restrain the degree of freedom of sliding of the linear guide member. That is, the positioning of the pallet is performed by retracting the positioning pin without moving the pallet up and down.

In this case, it is preferable to use a tapered locate pin type as the positioning pin,
Similarly, it is sufficient to use what is commercially available as a so-called linear guide as the linear guide member. Also,
During the positioning operation of the pallet by the positioning pin, the brake attached to the motor for driving the drive roller is released as in the conventional case, and the degree of freedom in the pallet conveying direction is also provided. Further, it is desirable that the locking means is a locate pin type having a tapered shape like the lock pin capable of projecting and retracting, that is, the positioning pin as described in claim 2.

Therefore, in the inventions according to claims 1 and 2, the pallet is pulled into the support frame by the pulling force of the drive roller as in the conventional case.
At this time, the degree of freedom of sliding by the linear guide member in the width direction of the pallet (direction orthogonal to the pallet transport direction) is restricted. When the pallet is placed on the support frame, the drive roller drive is stopped, the brake attached to the drive roller drive motor is released at the same time, and the lock state by the lock means is released to directly drive the drive roller. Allows the guide member to slide.

In this state, the pallet is positioned by projecting the positioning pin and fitting it into the pallet. At this time, if there is a stop position error in the pallet transfer direction and pallet width direction, the stop position error in the pallet transfer direction is absorbed by the pallet moving slightly with the drive roller as before, and at the same time the pallet width direction stop is stopped. The positional error is absorbed by the pallet moving slightly in the pallet width direction due to the degree of freedom of the direct-acting guide member together with the support frame. Therefore, the position of the support frame remains slightly displaced from the normal position.

When the predetermined assembling work for the work on the pallet is completed, the positioning pin is first removed from the pallet, and subsequently the locking means is brought into the locked state. As a result, the support frame is returned to the original regular position, and at the same time, the direct-acting guide member is constrained so that it cannot slide.

[0014]

According to the first aspect of the invention, the pallet is positioned by the protrusion of the positioning pin in a state where the linear motion type actuator has a sliding degree of freedom in the direction orthogonal to the pallet conveying direction. Also, the stop position error in the pallet width direction can be reliably absorbed, and the durability of the positioning pin is improved without applying an excessive force.

Further, since the pallet can be positioned by simply moving the positioning pin in and out without vertically moving the heavy pallet together with the supporting frame as in the prior art, the height of the equipment can be reduced, and
A large lift cylinder and guide mechanism are not required, and no pit is required, which has the effect of achieving downsizing and cost reduction of equipment.

According to the invention described in claim 2, since the lock pin capable of retracting is adopted as the locking means for restricting the sliding degree of freedom of the linear motion type guide member, the same as the invention described in claim 1. In addition to the above effect, there is an advantage that the sliding degree of freedom of the linear guide member can be restricted or restricted only by a simple retracting / retracting operation.

[0017]

1 and 2 are views showing a typical embodiment of the present invention, showing an example of a positioning device for a pallet type carrier used in a car body assembly line of an automobile. In particular, FIG. 1 shows a plan view and FIG. 2 shows a side view.

As shown in FIGS. 1 and 2, the pallet 1 which is the center of the pallet type conveying device is long and flat, and a floor main Fm which is, for example, a vehicle body panel has a plurality of fingers on its upper surface. It is configured to be positioned and supported via 2 or the like, and in this state, it is carried in to a specific stage S which will function as a pallet positioning stage in a vehicle body assembly line.

As shown in FIG. 1, a plurality of locator units R in the form of manipulators or robots having three orthogonal degrees of freedom of movement are arranged on both sides of the pallet 1 positioned on the stage S. And the floor main Fm transported with the pallet 1
Is positioned while being lifted up by each locator unit R, and is used for welding assembly work by, for example, a welding robot.

On the floor of the specific stage S which will function as the pallet positioning stage, a horizontal and long base frame 4 is provided via a plurality of posts 3.
Are arranged. A support frame 5 is mounted on the base frame 4, and a plurality of pairs of right and left pairs are formed on the pallet transport surface, which is the upper surface of the support frame 5, for loading and unloading the pallet 1 as in the conventional case. Drive roller 6 is mounted, and a drive motor 8 with a brake is mounted on one end of the support frame 5 via a bracket 7. Each of the drive rollers 6 is made of urethane, for example, and is provided with a flange so that the pallet 1 can move straight.

Pulleys are mounted coaxially and integrally with each drive roller 6 and the motor output shaft, and a winding transmission means 9 such as a toothed belt or a chain is provided between the adjacent drive rollers 6, 6 between the pulleys. It is wrapped around. Therefore, when the drive motor 8 is activated, the drive rollers 6 are driven to rotate at the same time, and the transport thrust is applied to the pallet 1 on the support frame 5. That is, when the pallet 1 is carried in from the previous process to the stage S, the pallet 1 is pulled in by the drive of the drive roller 6, and when the pallet 1 is carried out from the stage S to the subsequent process, the drive roller is similarly driven. The pallet 1 is sent out by the drive of 6.

Locating pin type positioning pin units 10 are provided at two front and rear positions of the base frame 4. As shown in FIG. 3, the positioning pin unit 10 accommodates a positioning pin 12 having a tapered tip that is directly driven up and down by a cylinder 11 in a housing 13 so that the positioning pin 12 can be retracted and retracted. The positioning hole 14 is fitted or released. Then, as will be described later, the positioning pin 12 is driven to rise with respect to the pallet 1 carried on the support frame 5 to be fitted into the positioning hole 14 on the other side, so that the pallet 1 is mechanically moved with respect to the base frame 4. It is designed to be positioned.

Here, the support frame 5 mounted on the base frame 4 is not fixed to the base frame 4 and has a slight degree of freedom in sliding in the direction orthogonal to the pallet conveying direction (pallet width direction). There is. That is, a pair of linear guides 15 are provided on the base frame 4 as two linear slide members at the front and rear thereof, and the support frame 5 is arranged in the direction orthogonal to the pallet conveying direction via the linear guides 15. It is slidably supported.

On the base frame 4, a locate pin type lock pin unit 16 as a lock means is provided adjacent to the linear guide 15. The lock pin unit 16 has substantially the same structure as that of the positioning pin unit 10 described above, and houses a lock pin 17 having a tapered tip, which is driven forward and backward by a cylinder, in a housing so that the lock pin 17 can be retracted. Therefore, the lock hole on the side of the support frame 5 is engaged with or released from the lock hole on the side of the support frame 5, that is, the locking and unlocking operations are performed in accordance with the retracting operation. Therefore, even though the support frame 5 has the slide freedom in the direction orthogonal to the pallet conveying direction due to the presence of the linear guide 15, the slide freedom is constrained so that it cannot slide when the lock pin 17 is in the locked state. Will be done.

According to the positioning device of the pallet type transporting device constructed as described above, as shown in FIGS. 1 and 2, each positioning pin is awaited while the pallet 1 is being carried into the stage S from the previous process. While 12 is descending, since each lock pin 17 is moving upward and is fitted in the lock hole on the side of the support frame 5, the linear guide 15
The degree of freedom of sliding by is kept constrained, and the support frame 5 is mechanically positioned with respect to the base frame 4 by the lock pin 17.

When carrying in the pallet 1 from the previous process on the stage S, the drive rollers 6 on the support frame 5 are simultaneously rotated in parallel with the application of the transport thrust to the pallet 1 in the previous process. When the pallet 1 is driven, a transport thrust is also applied to the stage S, so that the pallet 1 is drawn on each drive roller 6 from the previous step onto the support frame 5 of the stage S. Then, when the pallet 1 is pulled to a predetermined position on the support frame 5 and completely transferred,
The rotation of each drive roller 6 is stopped, and at the same time, the brake attached to the drive motor 8 is actuated to enter the braking state.

In this state, the lock pin 17 which has been in the locked state is lowered to be in the unlocked state, whereby the linear guide 15 interposed between the base frame 4 and the support frame 5 is restrained. After being unraveled, the linear guide will have the original degree of sliding freedom.

Then, after releasing the braking state of the brake attached to the drive motor 8, the pair of front and rear positioning pins 12 is moved up to fit the positioning pins 12 into the positioning holes 14 on the pallet 1 side. The pallet 1 is positioned by combining them. At this time, if the pallet 1 on the support frame 5 has a stop position error in the pallet conveying direction, the pallet 1 is moved in accordance with the fitting of the positioning pin 12 and the positioning hole 14 as in the conventional case. By slightly moving in the pallet conveying direction together with each drive roller 6, the above stop position error in the pallet conveying direction is absorbed.

At the same time, when the pallet 1 on the support frame 5 has a stop position error in the direction orthogonal to the pallet transport direction (pallet width direction), the fit between the positioning pin 12 and the positioning hole 14 is followed. As the pallet 1 slightly moves in the pallet width direction together with the support frame 5 due to the degree of freedom of the linear guide 15, the above stop position error in the pallet width direction is absorbed.

By completely fitting the positioning pin 12 and the positioning hole 14 on the pallet 1 side in this manner, the pallet 1 is absorbed while absorbing the stop position error of the pallet 1 in the pallet conveying direction and the pallet width direction. Are mechanically positioned at regular positions with respect to the base frame 4. Here, since even the support frame 5 slightly moves due to the degree of freedom of the linear guide 15 when the stop position error is absorbed in the pallet width direction, the lock pin 17 and the lock hole in the unlocked state are the same as those described above. Although it is in an eccentric state by the amount of stop position error absorption, this does not matter here.

When the pallet 1 is positioned by the positioning pins 12, the plurality of locator units R shown in FIG. 1 are operated to lift up the floor main Fm on the pallet 1 and position it at a predetermined position. , For example, for welding work by a welding robot.

When the predetermined welding operation is completed, the floor main Fm is transferred and positioned on the pallet 1 again.
Further, the positioning pin 12, which has positioned the pallet 1 up to that point, descends and the positioned state is released. At the same time, instead of the positioning pin 12, the lock pin 17 is lifted to bring the support frame 5 into a locked state, and the degree of freedom of sliding by the linear guide 15 is restricted. At this time, as described above, the lock pin 1 in the unlocked state
Although 7 and the lock hole were eccentric by the amount of the stop position error absorption, the eccentric state is eliminated by re-fitting the lock pin 17 and the lock hole.

After that, each drive roller 6 of the support frame 5 is rotationally driven, so that the pallet 1 is carried out to the next step.

As described above, according to the present embodiment, since the support frame 5 has the degree of freedom of sliding by the linear guide 15, the pallet 1 by the positioning pin 12 is provided.
At the time of positioning, it becomes possible to absorb the stop position error not only in the pallet conveying direction but also in the pallet width direction, and the durability is improved without applying an excessive force to the positioning pin 12.

Moreover, since the intended purpose can be achieved only by the vertical movement of the positioning pin 12 without raising and lowering the support frame 5 and the pallet 1 as in the conventional case, a large-scale lift mechanism is not required, and the equipment The simplification and the reduction of the height dimension can be achieved.

[Brief description of drawings]

FIG. 1 is a plan view showing the configuration of a pallet type transfer device used in a vehicle body assembly line as an embodiment of the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is an enlarged cross-sectional view of the positioning pin unit in FIG.

FIG. 4 is a structural explanatory view showing an example of a conventional pallet type conveying device.

[Explanation of symbols]

1 ... pallet 4 ... Base frame 5 ... Support frame 6 ... Drive roller 10 ... Positioning pin unit 12 ... Positioning pin 14 Positioning hole 15 ... Linear guide (direct acting guide member) 16 ... Lock pin unit (locking means) 17 ... Lock pin S ... Pallet positioning stage

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Akihito Inoue             Nissan, Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan             Inside the automobile corporation (72) Inventor Keiichi Matsukawa             Nissan, Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan             Inside the automobile corporation F-term (reference) 3C030 CC02 DA17 DA23 DA24 DA28                       DA34 DA38                 3D114 AA09 AA15 BA01 CA05 CA16                       DA01 DA04 DA05 EA13 FA02                       FA11 GA01 GA06

Claims (2)

[Claims] 1. A pallet positioning stage is provided with a support frame for supporting the pallet, and the pallet carrying surface of the support frame carries the pallet
Providing multiple drive rollers that are driven to rotate during unloading, the pallet loaded from the previous process is pulled into the support frame by the drive force of the drive roller, and the pallet is positioned by fitting with positioning pins. A positioning device for a pallet-type transfer device that is positioned on a stage, wherein the support frame is moved in a direction orthogonal to the pallet transfer direction via a direct-acting guide member on a fixed-position fixed base frame in the pallet positioning stage. In addition to being provided slidably, the base frame is provided with a retractable positioning pin that fits into a part of the pallet and positions the pallet, and further, in either one of the base frame and the support frame, During pallet positioning operation using positioning pins Outside the positioning device of the pallet type conveying apparatus characterized in that a locking means fitted to the other member of said base frame and the support frame to restrain the sliding freedom of the direct-acting guide member. 2. The positioning device for a pallet type conveying apparatus according to claim 1, wherein the lock means is a lock pin that can be retracted.