JPH0790487B2 - Floating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] In the invention of this application, a coupler of a type in which a taper pin is integrated in a guide hole is connected by a moving means such as a cylinder or a taught robot. In this case, even if the axial center of the taper pin and the guide hole are slightly misaligned, the coupler is properly coupled without absorbing a large load on the moving means and the robot side by absorbing the misalignment between them. It relates to an enabling device (this device is referred to herein as a floating device).

This type of floating device can be used, for example, for connecting a tool exchanging coupler used in an industrial robot, and for coupling a mold which is separated / integrated by moving means such as a cylinder.

[Conventional technology]

Usually, an arm type industrial robot is provided with a tool changing function, and has a tool changing coupler at the tip of the arm.

The tool exchanging coupler includes a first housing attached to the robot side and a second housing on the workpiece side to which the tool is attached, and a large number of second housings having different tools are prepared.

That is, when one process is completed and the next process is performed, the second housing which has been used up to now is removed from the first housing, and the second housing having another kind of tool is joined. The first housing and the second housing are provided with male / female connectors for connecting the electric / air / oil / water paths. By properly coupling the second housing to the first housing, Is turned on.

In order to properly connect these to each other in the first housing and the second housing, a taper pin whose diameter decreases toward the tip is erected on one of the joint surfaces of the first housing and the taper pin on the other joint surface. A guide hole for guiding is provided, and a floating device is interposed between the tip of the arm and the first housing.

Therefore, even if the teaching position of the first housing attached to the arm of the robot is slightly displaced from the position where the second housing is placed, as long as the tip end of the taper pin is within the range of insertion into the hole. Due to the presence of the floating device, the first housing moves with respect to the robot arm in a manner in which the taper pin is guided by the guide hole, and the first housing and the second housing can be properly connected. Then, in this state, a large load is not applied to the robot arm.

However, when the taper pin is inserted into the guide hole in the state where the joint surface of the first housing and that of the second housing are not parallel in the coupling of the tool exchange coupling, the conventional floating device is It was not possible to absorb the misalignment. Therefore, when the taper pin is inserted into the guide hole, there is a problem that a large load acts on the arm of the robot because it cannot be absorbed by the device. In some cases, the pin may break.

This is because the conventional floating device can absorb the deviation in the two-dimensional direction but cannot absorb the deviation in the three-dimensional direction.

Incidentally, even when the coupler is simply connected by the output part such as a cylinder, the same problem occurs.

[Problems to be Solved by the Invention]

Therefore, in the invention of this application, the taper pin is inserted into the guide hole in a state where the joint surfaces of the two housings forming the coupling are not parallel by making it possible to absorb the deviation in the three-dimensional direction. Even in such a case, it is an object to provide a floating device in which a large load does not act on the moving means such as a cylinder or the robot side.

[Means for solving the problem]

The invention according to claim 1 of this application relates to a floating device, which is arranged between the output part of the moving means and one of the housings constituting the coupler, and comprises a fixed body (1) and a driven body (2). ) Are arranged with a small gap (g) provided therebetween, and a minute relative movement between the fixed body (1) and the driven body (2) in the axial direction of the device and in the direction perpendicular thereto. In a floating device having elastic means (4) for enabling return, a plurality of shaft bodies parallel to one shaft core of the fixed body (1) and the driven body (2) are provided and each shaft body is provided on the other side. A through hole (12) having an inwardly projecting flange (13), which is loosely inserted, is formed, and an enlarged diameter which is integral with or locked to a shaft portion which penetrates through the inwardly projecting flange (13). Part and the inward protruding collar (1
A ball (35) is interposed between the enlarged portion and the through hole (12), and the enlarged portion has a smaller diameter than the through hole (12) so as to form a small gap between the enlarged portion and the through hole (12).

In the above apparatus, the elastic means (4) includes a first elastic means (4a) for enabling a minute relative movement between the fixed body (1) and the driven body (2) in a direction perpendicular to the axis.
The fixed body (1) and the driven body (2) are composed of a second elastic means (4b) for enabling a minute relative movement in the axial direction.

[Action]

 The invention of this application has the following actions.

Between the enlarged diameter part of the shaft and the inward protruding collar (13), the ball (3
Since 5) is interposed, the fixed body (1) and the driven body (2) are opposed to each other in the direction perpendicular to the axial center against the elastic force of the elastic means (4) due to the rolling of the ball (35). You can move.

Further, since there is a gap between the shaft body and the inward projecting brim (13), the driven body (2) can be moved in the axial direction by elastic deformation of the elastic means (4), Furthermore, the driven body (2) can be inclined with respect to the axis.

Here, the amount of movement of the driven body (2) in the axial direction and the direction perpendicular thereto, and the amount of movement inclined to the axial center are limited to a small amount due to contact between the enlarged diameter portion and the through hole (12). There is.

That is, in the floating device of the present invention, the driven body (2) can move in the three-dimensional direction with respect to the fixed body (1) by a minute amount, and the movement can be suppressed to a minute amount. Elastic return to the state without difficulty.

〔Example〕

Hereinafter, the configuration of the invention of this application will be described with reference to the drawings shown as an embodiment.

As shown in FIGS. 1 to 4, the floating device of this embodiment has a fixed body (1) attached to an output part of an industrial robot and a first housing (constituting a tool exchange coupler (6)). A driven body (2) to which the fixed body (60) is attached, and the fixed body (1) and the driven body (2) are arranged with a small gap (g) having a constant width. ) Is supported by the fixed body (1) via the first elastic means (4a) and the second elastic means (4b).

Hereinafter, each of the above-mentioned configurations will be described in detail.

"Fixed body (1)" The fixed body (1) is formed in a thick disk shape as shown in Figs. 1 to 3, and has a shaft hole (10) penetrating in the center thereof. And horizontal holes (11) for coil storage which are open to the shaft hole (10) are formed at 120 ° intervals.
Further, between the lateral holes (11) (11), as shown in FIG.
A through hole (12) having an inwardly projecting flange (13) is formed in the central portion. Furthermore, this fixed body (1) is provided with a screw hole (14) on its upper surface for attaching to the output end side of the robot.

"Following body (2)" As shown in Figs. 1 and 3, the driven body (2) is formed in a thin disk shape having the same diameter as the fixed body (1), and is formed in the center thereof. Is the shaft (2) inserted into the shaft hole (10) described above.
0) is projected. As shown in the figure, a shallow hole (21) corresponding to the through hole (12) is formed on the surface of the driven body (2) facing the fixed body (1),
Further, a screw hole (22) is formed at the center of the bottom of the shallow hole (21).

As shown in FIGS. 2 and 3, the shaft portion (20) described above has a chamfered portion (23) corresponding to the lateral hole (11) on the peripheral surface thereof.
Are formed, and the overall cross-sectional shape is a substantially equilateral triangle.

"Supporting the follower (2) to the fixed body (1)" In the assembled state shown in Fig. 3 in which the shaft portion (20) is inserted into the shaft hole (10), the shaft hole (21) penetrates the shallow hole (21). The hole (12) forms a hole (H) extending from the fixed body (1) to the driven body (2), while the chamfered portion (23) of the shaft portion (20) is an open portion of the lateral hole (11). It is facing us.

Then, between the bottom surface of the lateral hole (11) and the chamfered portion (23) of the shaft portion (20) in the fixed body (1), as shown in FIG.
A compression coil spring (40) is interposed between the shaft (20) of the driven body (2) by the compression coil spring (40).
Bias is applied from three directions at 0 ° intervals. Therefore, the driven body (2) is coaxially supported by the fixed body (1) by the balance of the biasing forces of the three compression coil springs (40).

Further, as shown in FIG. 3, the bearings (30) and (31) are housed in the hole (H) so as to sandwich the inward protruding collar (13), and the bearing (30) (31) is located on the shallow hole (21) side. The above-mentioned bearing (the ball receiving member (34) on one side of 31 and the annular elastic plate (41) made of urethane (may be a disc spring laminated back up) may be housed. The diameter of the outer ball receiving member (39) in (30) is set to be slightly smaller than that of the other ball receiving members (34).

Then, the bolt (32) is screwed into the screw hole (22) so as to be loosely inserted into the bearing (30) (31) and the elastic plate (41),
By tightening the nut (33) into this bolt (32),
The driven body (2) is supported by the fixed body (1) via the bearings (30) and (31) and the elastic plate (41).

That is, the above-mentioned compression coil spring (40) corresponds to the first elastic means (4a), the elastic plate (41) corresponds to the second elastic means (4b), and the bolt 32, the nut 33 and the ball receiver. Element
Reference numeral 39 corresponds to the shaft body and the enlarged diameter portion of the means column.

In addition, the elastic plate (41) and the bearings (30) and (31) are, in a state where the fixed body (1) and the driven body (2) are integrated,
As shown in the figure, it is set so that a small gap (g) having a constant width is formed between them.

Further, as shown in the figure, the ball receiving member (34) is formed in an annular flat plate shape, and unlike a normal thrust bearing, does not have a groove for guiding the ball (35).

"Movement of Floating Device itself" Since this floating device is configured as described above, the driven member (2) has the outer diameter of the bearing member (39) and the through hole (12) with respect to the fixed member (1). ), It is possible to move in the direction perpendicular to the axial center against the biasing force of the compression coil spring (40) only in the range corresponding to the gap between the two.

Further, the driven body (2) can move in the axial direction against the fixed body (1) by the small gap (g) against the urging force of the elastic plate (41). The body (2) can change its axial center relative to the fixed body (1) by an amount corresponding to the small gap (g).

"Application to Industrial Robot with Arm" The floating device of this embodiment can be mounted in the same manner as the conventional one. That is, as shown in FIG. 4, the fixed body (1) is attached to the output end (90) of the arm (9) by screws, and the driven body (2) is attached to a tool exchanging coupler (to be described later). 6) 1st housing (60)
Is installed.

"Schematic Description of Parts Related to the Invention in Tool Exchange Coupler (6)" This tool exchange coupler (6) includes a first housing (60) and a second housing (60) as shown in Figs. 1 to 3. And a first housing (6).
The taper pin (62) is erected on the joint surface of (0) and
The taper pin (62) is provided on the joint surface of the second housing (61).
A guide hole (63) corresponding to is formed.

The first housing (60) and the second housing (61) are equipped with male / female connectors for connecting electric / air / oil / water paths, and the taper pin (62) has guide holes (6).
In the state of being fitted in 3), the second housing (61) is connected to the first housing at an appropriate position so that the path is turned on (not shown).

"Functional Effects of Floating Device when Applied to the Above Industrial Robot" The teaching position of the first housing (60) by the arm (9) of the robot and the position where the second housing (61) is placed are tapered pins ( The tip of 62) has a guide hole (6
When the position is displaced within the range to be inserted in 3), there are the following modes, and when the floating device of this embodiment is used, the following operational effects are obtained.

． When the axial center of the taper pin (62) and the axial center of the guide hole (63) are parallel to each other as shown in FIG. 5 (two-dimensional misalignment).

The taper pin (62) is guided by the guide hole (63) and moves to the fifth position.
As the solid line shown in the figure moves to the two-dot chain line state, the driven body (2) resists the biasing force of the compression coil spring (40),
It moves in the direction perpendicular to the axis with respect to the fixed body (1). That is, this type of misalignment is caused by the compression coil spring (4
It is absorbed by the elastic deformation of 0), and as a result, the state in which the taper pin (62) is fitted in the guide hole (63), that is, the first housing (60) and the second housing (61) are properly adjusted. In the connected state, the force acting on the robot arm (9) and the taper pin (62) is only due to the elastic return force of the compression coil spring (40).

． When the axial center of the taper pin (62) and the axial center of the guide hole (63) intersect as shown in FIG. 6 (three-dimensional misalignment).

The taper pin (62) is guided by the guide hole (63) and moves to the sixth position.
As the solid line moves from the solid line to the two-dot chain line in the figure, the driven body (2) resists the urging force of the compression coil spring (40) and the elastic plate (41) and the axis of the fixed body (1) with respect to the fixed body (1). It moves in the direction of the heart and the direction perpendicular to this. That is, this kind of positional deviation is absorbed by the elastic deformation of the compression coil spring (40) and the elastic plate (41), and as a result, the taper pin (62) is fitted in the guide hole (63), that is, , When the first housing (60) and the second housing (61) are properly connected, the force acting on the joint part of the robot arm (9) and the taper pin (62) is the compression coil spring (40) and the elastic force. Only due to the elastic restoring force of the plate (41).

Thus, when adopting this floating device,
Even if there is a deviation due to the above-mentioned mode, a large load is not applied to the arm (9) and the taper pin (62).

Incidentally, in the above-mentioned embodiment, the coupling described in the section of the means is a tool exchange coupling, but the coupling is not limited to this, and may be constituted by a pair of housings. It can also be used for coupling a mold such as a molding die having a pair of molds.

Further, in the above embodiment, the floating device of the invention of this application was used for connecting / disconnecting the coupling for tool exchange by the robot.
It can also be used for connecting and disconnecting fluid couplings.

〔The invention's effect〕

Since the present invention has the structure as described above, it has the following effects.

Since the driven body (2) can move in the three-dimensional direction with respect to the fixed body (1), in the state described in the section of the prior art, the joint surfaces of the two housings forming the coupling are not parallel to each other. Even when the taper pin is fitted into the guide hole, the force acting on the moving means or robot and the taper pin is only due to the elastic return force of the elastic means (4). That is, compared with the case where the conventional floating device is mounted, the load acting on the moving means and the robot side is small. Further, when the taper pin is pulled out from the guide hole, the positional relationship between the fixed body (1) and the driven body (2) is automatically returned to the original state.
It is not necessary to manually adjust the positional relationship between the fixed body (1) and the driven body (2) for each work.

[Brief description of drawings]

FIG. 1 is an overall perspective view of a floating device and a coupling attached thereto according to the invention of this application, FIG. 4 is a top view of the floating device, a relationship diagram between a coupling and a robot, and FIG. 3 is the floating device. 2 is a sectional view of the coupling and a side view of the coupling, FIG. 2 is the floating device, FIG. 5 is an explanatory diagram for absorbing a two-dimensional misalignment by the floating device, and FIG. 6 is a three-dimensional drawing by the floating device. It is explanatory drawing at the time of absorbing a direction gap, (1) ... fixed body, (2) ... driven body (4) ... elastic means, (4a) ... 1st elastic means (4b) in the figure. ) …… Second elastic means, (g) …… Small gap

Claims (2)

[Claims] 1. A small gap (g) is provided between an output part of a moving means and one of housings constituting a coupler, wherein a fixed body (1) and a driven body (2) are provided with a small gap (g). The elastic means (4) is arranged between the fixed body (1) and the driven body (2) and enables minute relative movement / return in the axial direction of the device and in the direction perpendicular thereto. In the floating device having B), one of the fixed body (1) and the driven body (2) is provided with a plurality of shaft bodies parallel to the shaft core, and the other is provided with an inward projecting flange in which each shaft body is loosely inserted. A through hole (12) having (13) is bored, and an enlarged diameter portion that is integral with or locked to the shaft portion that penetrates through the inward protruding collar (13) and the inward protruding collar. (1
The ball (35) is interposed between the enlarged portion and the through hole (12), and the enlarged portion has a diameter smaller than that of the through hole (12) so as to form a small gap between the enlarged portion and the through hole (12). Floating device. 2. A first elastic means (4a) for enabling minute relative movement between the fixed body (1) and the driven body (2) in a direction perpendicular to the axis, and fixing the elastic means (4). The floating device according to claim 1, characterized in that it comprises a second elastic means (4b) for enabling minute relative movement in the axial direction between the body (1) and the driven body (2). .