JPH1170417A - Positioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a drive mechanism for replacing a receiving piece, and perform positioning in accordance with more part shapes. SOLUTION: Receiving pieces 6a and 6a' abut on the inner wall 13a having an earthenware mortar state, by stretching upward elastic body rods 7 and 7a by means of hydraulic cylinders 8 and 8a, to slide on the surface of an amphitheaten-like inner wall 13, as shown by a sign 6a''. At that time, the elastic body rods 7 and 7a are elastically deformed, and the receiving piece 6a and a receiving piece 6a'' move toward an opening 13b. Moreover, the receiving 6a is inserted into the opening 13b to be protruded from a housing 13, as shown by a sign 6a'''. The number of the receiving pieces 6 can be increased any number if the pieces 6 can be housed in the inside of the housing 13, and of course, the number of the receiving pieces 6 for being housed can be increased with the enlargement of the housing 13.

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 positioning a plurality of parts by holding the parts in a work such as a welding work in which a plurality of parts need to be maintained in a predetermined positional relationship.

[0002]

2. Description of the Related Art For example, in the case of a welding line of an automobile, it is a general practice to simultaneously flow parts of a plurality of models on the same line and perform welding work corresponding to each model on each of the parts. In this case, it is necessary for the component positioning device to surely position components in correspondence with different component shapes of different vehicle types. For this reason, various positioning devices have been devised that can make the jig shape correspond to the component shape.

[0003] As a conventional example, Japanese Patent Publication No. 60-57957 and Japanese Utility Model Application Laid-Open No. 64-9024 disclose a laminated body formed by laminating mutually slidable plates of the same shape. A method is disclosed in which the relationship is changed so that the end face shape of the laminated body matches the component shape.

[0004] Japanese Utility Model Publication No. 6-34907 discloses a technique of replacing a receiving piece for holding a component in accordance with the shape of the component. The device includes a pair of receiving pieces 1 and 2 as shown in FIG. One of the receiving pieces 1 is fixed to the arm 3, and the arm 3 is driven by the cylinder 4 in the direction of arrow A. The other receiving piece 2 is fixed to an index device 5 rotatable in the arrow B direction. Incidentally, the index device 5 is provided with four types of receiving pieces 2 (2a to 2d) each having a different shape. Then, the index device 5 is rotated to select a receiving piece corresponding to the component shape to be positioned from these four types of receiving pieces, and the selected receiving piece (2a in the illustrated example) faces the receiving piece 1. Stop in position. Then, by driving the cylinder 4, the receiving pieces 1, 2 are brought into contact with the components, and are held and positioned.

[0005]

However, the above-mentioned prior art includes the following problems. First, the method disclosed in Japanese Patent Publication No. 60-57957 and the like has a complicated structure for matching the end face shape of the laminated body to the component shape, which leads to a complicated apparatus and control contents, and an increase in the size of the apparatus. Met. In addition, dust and spatter may enter between the plate members constituting the laminated body, thereby deteriorating the operation accuracy and causing damage to the device, and there are many unresolved portions in terms of reliability and durability of the device. there were.

On the other hand, the technique disclosed in Japanese Utility Model Publication No. 6-34907 limits the number of compatible component shapes to four (because there are four types of receiving pieces 2). Is promoted, and the reliability and durability are high. However, there are problems to be solved, for example, the index device itself is expensive and it is difficult to correspond to four or more types of component shapes.

The present invention has been made in view of the above problems, and an object of the present invention is to simplify a driving mechanism for exchanging a receiving piece in a positioning device for holding a work between opposing receiving pieces, Another object of the present invention is to make it possible to perform positioning in accordance with more component shapes.

[0008]

According to the present invention, there is provided a positioning device for holding a work between opposed receiving pieces, wherein at least one of the opposed receiving pieces has a central portion. It is supported by an elastic rod in a housing having an open mortar-shaped inner wall, and is formed so as to be able to protrude from the opening by displacing the elastic rod toward the mortar-shaped inner wall. .

According to the above configuration, the receiving piece abuts on the mortar-shaped inner wall by displacing the elastic rod toward the mortar-shaped inner wall. The contact position at this time may be any place on the mortar-shaped inner wall. Subsequently, the displacement of the elastic rod causes the receiving piece to slide on the surface of the mortar-shaped inner wall, and the elastic rod is elastically deformed to move the receiving piece toward the opening. Further, the receiving piece projects from the housing through the opening.

In the present invention, it is desirable that the elastic rod is driven by a hydraulic cylinder.
The fluid pressure cylinder can be driven only by withdrawal of the pressurized fluid, and the operation of the receiving piece can be controlled by setting the stroke of the cylinder to the amount of movement required for the receiving piece.

Further, in the present invention, it is desirable that the receiving piece is provided with two or more types. With this configuration, selection of the receiving piece according to the shape of the work to be held,
Replace.

In addition, in the present invention, it is preferable that the cylinders are arranged at the same circumference and at equal intervals around the opening of the housing with respect to the housing. With this configuration, the distance between each cylinder and the opening of the housing is all the same. Then, the amount of projection when each receiving piece projects from the opening of the housing and the shape of the tip portion are set only by the piece shape, and the length of the elastic rod and the setting of the stroke of each cylinder are all the same.

In addition, it is preferable that the elastic rod forms a part of an internal rod of the hydraulic cylinder. With this configuration, the connecting means between the elastic rod and the internal rod is not required, and the sealing between the cylinder and the internal rod is ensured by the elasticity of the rod.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, the same or corresponding parts as in the conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 1 is a sectional view of a positioning device according to an embodiment of the present invention. FIG. 2 is a top view of the positioning device shown in FIG. 1, and FIG. 3 is an enlarged cross-sectional view taken along line CC of FIG. In addition, when referring to FIG. 1, the vertical direction of the figure is described as up and down, and the horizontal direction of the figure is described as left and right.

In the positioning device according to the embodiment of the present invention, as shown in FIG. 1, a work (not shown) is sandwiched between opposed receiving pieces 1 and 6, thereby positioning the work. The lower receiving piece 6 has a plurality of types (only four types 6a to 6d are shown in FIG. 1) in a substantially cylindrical housing 13 according to the type of work to be held. Is stored. Also, the housing 13
Is formed with a mortar-shaped inner wall 13a, and an opening 13b penetrating in the vertical direction is provided at the center of the mortar-shaped inner wall 13. And the cross-sectional shape of each receiving piece 6 is
Each of them has a shape (see FIG. 4) that can pass through the opening 13b.

By the way, each receiving piece 6 (6a to 6d)
Each is supported by the elastic rods 7 (7a to 7d). Each of the elastic rods 7 is driven by a hydraulic cylinder 8 (8a to 8d). 1 and 3
As shown in the figure, the lower end of the hydraulic cylinder 8 is
With respect to the bottom plate 9 fixed to the housing 13 through a bracket 10 and a hinge pin 11, it is swingably fixed. Further, the respective hydraulic cylinders 8 are arranged at equal intervals on the same circumference as shown in FIG. 3, and are pivotally supported so as to be separated from and approach the center of the circumference. Each hydraulic cylinder 8 is urged by a spring member 12 (such as a wire spring) fixed to the bracket 10 in a direction away from the center of the circumference.

As shown in FIG. 1, since each receiving piece 6 is stored in the housing 13, each receiving piece 6 comes into close contact with the inner wall of the housing by the urging force of the spring member 12. Then, as shown in FIG. 2, they are arranged at equal intervals on the same circumference. The positioning device according to the present embodiment
Eight hydraulic cylinders 8 are provided. Each of the hydraulic cylinders 8 drives an elastic rod 7 (FIG. 1), and each of the elastic rods 7 causes a different type of receiving piece 6 to move.
Can be supported. Therefore, in the present embodiment,
As shown in FIG. 2, up to eight (eight types) receiving pieces 6 can be built in on the same circumference and at equal intervals.

The material of the elastic rod 7 is as follows.
Various materials such as metal and synthetic resin can be used, but they must have a rigidity as described later. The elastic rod 7 is formed of a material having compression resistance and lubricity such as a fluororesin, and forms a part of the internal rod of the hydraulic cylinder 8 (that is, the elastic rod 7 is It is also possible to use the inner rod of the cylinder 8). FIG. 1 shows an integral rod structure. By adopting such an integral rod structure,
The connecting means between the elastic rod 7 and the internal rod of the hydraulic cylinder 8 can be eliminated. In addition, the sealing between the cylinder and the internal rod can be ensured by the elasticity of the rod, and the oil resistance, flame resistance, insulation, and the like can be improved while eliminating the seal in the cylinder tube.

Further, the present positioning device is provided with a locking device for fixing the receiving piece 6 against a reaction force at the time of holding the work at a projecting position of the receiving piece 6 described later (state of 6a in FIG. 1). It has. The lock device 15 is provided near the upper end of the housing 13. FIG. 4 is a top view of the positioning device shown in FIG. FIG. 5 is a longitudinal sectional view of FIG. As shown in FIG. 4, the lock device 15 includes a fluid pressure cylinder 16, and the lock pin 17 is moved by a cylinder rod 16a in a direction orthogonal to the piece 6. The lock pin 17 has a large-diameter portion 17a and a small-diameter portion 17b, so that either the large-diameter portion 17a or the small-diameter portion 17b can face the receiving piece 6. Also,
As shown in FIG. 5, the receiving piece 6 is formed with an annular groove 18 so as to be able to engage with the large-diameter portion 17a of the lock pin 17 when the receiving piece 6 is at a projecting position described later.

As shown by the solid line in FIG. 4, when the small diameter portion 17b of the lock pin 17 is located at a position facing the receiving piece 6, the small diameter portion 17b is in a state of avoiding the moving path of the receiving piece 6. Therefore, the receiving piece 6 can pass through the opening 13b.
As shown by the two-dot chain line in FIG. 4, when the large diameter portion 17a of the lock pin 17 is located at a position facing the receiving piece 6, the locking pin 17 protrudes into the opening 13b which is the moving path of the receiving piece 6. . Then, it engages with the annular groove 18 of the receiving piece 6, and fixes the receiving piece 6 at this position. The vertical force in FIG. 5 applied to the receiving piece 6 is received by the lock pin 17,
The reaction force does not reach the elastic rod 7.

In the present embodiment, an example is shown in which the hydraulic cylinder 16 is used for the lock device 15, but the present invention is not limited to this. For example, a hydraulic cylinder 19 described later
By transmitting the operation of FIG. 1 to the lock pin 17 by a cam or the like, the lock device 15 can be driven. The point is that whatever method is used, it is sufficient that a lock device for fixing the receiving piece 6 to the projecting position against the reaction force at the time of holding the work is provided.

Here, an operation procedure when the work is clamped by the positioning device having the above configuration will be described with reference to FIG. Here, the case where the receiving piece 6a of the plurality of receiving pieces 6 is operated will be described.

(1) When the fluid pressure cylinder 8a is at the bottom dead center of its movable stroke, the receiving piece 6a is at the "storage position" indicated by reference numeral 6a '. (2) When the fluid pressure cylinder 8a is operated and the elastic rod 7 is gradually extended, the receiving piece 6a 'rises while sliding on the surface of the mortar-shaped inner wall 13a, and is indicated by reference numeral 6a ". At this time, the fluid pressure cylinder 8a moves toward the opening 13b, and the hydraulic cylinder 8a
Around the opening 13b to assist the movement of the receiving piece 6a. (3) When the elastic rod 7 is further extended, the receiving piece 6
a "starts insertion into the opening 13b as indicated by reference numeral 6a"'. At this time, the elastic rod 7 is curved as shown by a solid line in the drawing, and the axial direction of the receiving piece 6a can be made to coincide with the axial direction (vertical direction) of the opening 13b.

(4) When the fluid pressure cylinder 8a reaches the top dead center of its movable stroke or before the top dead center by some stopper, the receiving piece 6a is moved to the position shown in FIG.
Is positioned at the “projecting position” indicated by the solid line. (5) The receiving piece 6a is fixed to the projecting position by the lock device 15. (6) When setting the work on the positioning device, the receiving piece 1 is temporarily evacuated. The fluid pressure cylinder 19 that drives the arm 3 extends upward from the state shown in FIG. 1 during a certain stroke and can rotate thereafter. (7) Then, the work (not shown) is set on the receiving piece 2, and the evacuated receiving piece 1 is returned to the position shown in FIG. 1 again, whereby the work is held between the receiving pieces 1 and 6a.

(8) When replacing the receiving piece 6a with another receiving piece, first, the fixing of the position of the receiving piece 6a by the lock device 15 is released. Subsequently, by contracting the fluid pressure cylinder 8a at the top dead center of the movable stroke, the receiving pieces return to the storage position in the order of 6a "', 6a", 6a'.
At this time, the fluid pressure cylinder 8a that has been rotated in the direction of the opening 13b can return to the storage position again by the bias of the spring member 12. Then, the hydraulic cylinders of the other receiving pieces are operated, and the receiving pieces are fixed at the protruding positions in the same procedure as the steps (1) to (5). FIG.
, The protruding positions of the other receiving pieces are indicated by dashed lines.

As can be understood from the above description, the elastic rod 7 has rigidity enough to keep the receiving piece 6 always upward while moving the receiving piece 6 between the retracted position and the protruding position. Required. However, if the rigidity of the elastic rod 7 is too high, it is difficult to insert the receiving piece 6a through the opening 13b in steps (3) to (4). Incidentally, the reaction force applied to the receiving piece 6 when the work is clamped is received by the lock device 15, so that the reaction force does not reach the elastic rod 7. Therefore, when determining the rigidity of the elastic rod 7, the reaction force does not need to be taken into consideration.

The operation and effect obtained from the embodiment of the present invention having the above configuration are as follows. Multiple receiving pieces 6
Are arranged on the same circumference and at equal intervals in the storage position. Therefore, the receiving piece 6 is located at a position outside the opening 13b of the housing 13 in the storage position. However, each receiving piece 6 is supported by the elastic rod 7 and
Since the opening 13b is formed at the center of the mortar-shaped inner wall 13a, the receiving piece 6 slides on the surface of the mortar-shaped inner wall 13a by extending the elastic rod 7 upward in FIG. Then, the elastic rod 7 is elastically deformed to move the receiving piece 6 toward the opening 13b.
Since the lower end of the fluid pressure cylinder 8 is rotatable with respect to the bottom plate 9, the movement of the receiving piece 6 to the opening 13b is assisted.

In other words, the storage position of the receiving piece 6 can be any position as long as it faces the mortar-shaped inner wall 13a. Positioning can be performed at the position. The number of receiving pieces 6 is
13 can be expanded as long as it can be accommodated inside 13. Naturally, if the housing 13 is made larger, the number of receiving pieces that can be stored increases. Further, even if the number of the receiving pieces 6, the elastic rods, and the fluid pressure cylinders 8 is increased by enlarging the housing, the apparatus as a whole does not become extremely large. In the present embodiment, up to eight (eight types) receiving pieces 6 are built-in, and thus, it is possible to hold up to eight types of works. Also, if two receiving pieces of the same shape are provided (four types are built in),
Even if a failure occurs in the receiving piece, it is possible to immediately replace the receiving piece with a new receiving piece.

The elastic rod 7 supporting the receiving piece 6 is driven by a fluid pressure cylinder 8. By setting the bottom dead center of the movable stroke of the fluid pressure cylinder 8 to the storage position of the receiving piece 6 and the top dead center to the protruding position, only the withdrawal of the pressure fluid to the hydraulic pressure cylinder 8 allows the receiving piece to be moved. 6 can be controlled. In the present embodiment, three types of hydraulic cylinders 8, 1
6, 19 are used, and it is possible to use a common pressure fluid supply source for each cylinder. Therefore, the overall configuration of the device can be simplified as compared with a positioning device using a conventional index device.

In this embodiment, since the fluid pressure cylinders 8 are arranged at the same circumference and at equal intervals, the distance between each cylinder 8 and the opening 13b of the housing can be all the same. Therefore, the setting of the projecting amount and the tip shape when each receiving piece 6 projects from the opening 13b of the housing is performed only by the receiving piece shape, and the length of the elastic rod 7 and the stroke of each cylinder 8 are all set. Can be the same. For this reason, the cost of each cylinder 8 can be reduced.

Further, since the elastic rod 7 also serves as the internal rod of the hydraulic cylinder 8, the number of components can be reduced, and the number of assembly steps and the cost of parts can be reduced.
If a material having compression resistance and lubricity such as a fluororesin is used as the material of the elastic rod 7, the sealing between the cylinder and the internal rod can be ensured by the elasticity of the rod. Thus, oil resistance, flame resistance, insulation and the like can be improved while eliminating the seal in the cylinder tube.

[0033]

According to the present invention, the following effects are obtained. First, according to the positioning device according to claim 1 of the present invention, only by displacing the receiving piece upward by the elastic rod, the receiving piece moves along the mortar-shaped inner wall and projects from the opening of the housing. Let it. Therefore, replacement of the receiving pieces can be performed only by displacement of the elastic rod.

According to the positioning device of the second aspect of the present invention, by driving the elastic rod by the hydraulic cylinder, it is possible to control the operation of the receiving piece only by withdrawing the pressure fluid into and from the cylinder. Become. Therefore,
It is possible to perform the work of exchanging the receiving pieces with simple control contents.

According to the positioning device of the third aspect of the present invention, by providing two or more types of receiving pieces,
The receiving pieces can be exchanged according to the shape of the work to be sandwiched, and various works can be reliably positioned.

Furthermore, according to the positioning device of the fourth aspect of the present invention, the length of the elastic rod supporting the receiving piece,
The setting of the stroke of each cylinder can be all the same, and the cost can be reduced by sharing these components.

In addition, according to the positioning device of the fifth aspect of the present invention, it is possible to simplify the configuration of the elastic rod for driving the receiving piece and the structure of the fluid pressure cylinder, thereby reducing the cost of parts. It becomes possible to plan.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a positioning device according to an embodiment of the present invention, showing a partial operation trajectory.

FIG. 2 is a top view of the positioning device shown in FIG.

FIG. 3 is an enlarged cross-sectional view taken along line CC of FIG. 1;

FIG. 4 is a top view of the positioning device according to the embodiment of the present invention shown in FIG. 2, in which the vicinity of the lock device is shown in cross section and enlarged.

FIG. 5 is a longitudinal sectional view of FIG. 4;

FIG. 6 is a schematic view showing a conventional positioning device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Receiving piece 6 Receiving piece 7 Elastic rod 8 Fluid pressure cylinder 13 Housing 13a Mortar-shaped inner wall 13b Opening

Claims (5)

[Claims] 1. A positioning device for clamping a work between opposed receiving pieces, wherein at least one of the opposed receiving pieces is supported by an elastic rod in a housing having a mortar-shaped inner wall having an open central portion, and A positioning device which is formed so as to protrude from the opening by displacing the elastic rod toward the mortar-shaped inner wall. 2. The positioning device according to claim 1, wherein said elastic rod is driven by a hydraulic cylinder. 3. The positioning device according to claim 2, wherein at least two types of said receiving pieces are provided. 4. The positioning device according to claim 3, wherein the cylinders are arranged at the same circumference and at equal intervals with respect to the housing around an opening of the housing. 5. The hydraulic rod according to claim 2, wherein the elastic rod forms a part of an internal rod of the hydraulic cylinder.
The positioning device according to any one of claims 1 to 4.