JPH0347797Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention clamps and grips an assembled part from a straight direction by bringing a pair of gripping members relatively close to each other, and also grips the assembled part. This invention relates to a gripping device that is assembled to a part to be assembled by engaging the part while holding the grip and rotating the part around an axis in the linear direction.

BACKGROUND OF THE INVENTION In various types of assembling devices, various types of assembling parts are gripped by gripping devices to convey them to predetermined assembling positions.
One type of such a gripping device is one in which a pair of gripping members are moved relatively close to each other to clamp and grip an assembled component from a straight direction. Conventionally, such gripping devices have been used for the sole purpose of transporting parts to be assembled to a predetermined assembly position. In conventional methods, the parts to be assembled that are released from the gripping device are usually assembled using another device.

On the other hand, the inventors of the present application grip the assembly parts in a fixed posture using a gripping device, transport them to an assembly position, and place the assembled parts in a predetermined fixed posture at the assembly position. We considered whether it would be possible to engage the assembly part with the part, rotate it around the axis in the linear direction while gripping the assembly part, and then assemble it to the part to be assembled. In other words, since the conventional gripping device grips the assembly part by bringing the gripping member into direct contact with the assembly part, the assembly is performed by causing slippage between them around the axis in the linear direction. The parts are assembled to the parts to be assembled while rotating them.

On the other hand, abutting tools are attached to the pair of gripping members so as to be rotatable about the axes in the linear direction, and the workpiece is gripped via the abutting tools, and the abutting tools are forcibly rotated by a drive device. For example, a gripping device that rotates a workpiece around an axis in a linear direction by
It is described in Japanese Utility Model Publication No. 121978 and Japanese Utility Model Application Publication No. 51-1232773, and it is also possible to use this for assembling the above-mentioned assembly parts. In other words, if the rotation speed and amount of rotation of the abutment tool are controlled in relation to the movement of the gripping device so that the part to be assembled as a work is assembled to the part to be assembled, it can be used as an assembly device. It is possible.

Problems to be Solved by the Invention However, in the former method, in which the parts to be assembled are assembled by engaging them with the parts to be assembled, the parts to be assembled are simply held by squeezing from a straight line direction. When the assembled part is engaged with the assembled part and a force is applied, the assembled part not only rotates around the axis in the linear direction but also moves in the direction of the applied force. Also, the center of rotation of the assembled parts is not necessarily constant,
This varies depending on the gripping conditions and the like.
If the center of rotation shifts or shifts in this way, it becomes impossible to correctly assemble the parts to be assembled to the parts to be assembled, resulting in assembly failure.

On the other hand, in the latter case where the parts to be assembled are forcibly rotated, the center of rotation of the parts to be assembled does not move or shift, but in order to correctly assemble the parts to the part being assembled, The rotational speed and amount of rotation of the abutting tool must be controlled with high accuracy in relation to the movement of the gripping device so that they do not interfere with each other, and the setting is troublesome and the device becomes complicated and expensive. It's put away.

The present invention was developed against the background of the above circumstances, and its purpose is not only to simply grasp and transport the parts to be assembled to the assembly position, but also to always correctly assemble the parts to be assembled. The object of the present invention is to provide a simple and inexpensive gripping device that can perform the following tasks.

Means for Solving the Problems In order to achieve the above object, the present invention makes a pair of gripping members relatively close to each other, thereby pinching and gripping the assembly parts from a straight direction, and also gripping the assembly parts to the assembly position. By engaging the assembled part with the assembled part that has been transported and placed at the assembly position, the assembled part is rotated around the axis in the linear direction while gripping the assembled part. a gripping device that is assembled into a gripping device, wherein a pair of gripping members are disposed in portions of the pair of gripping members that contact the assembled component so as to be rotatable about respective axes in the linear direction while gripping the assembled component; an abutting tool;
(b) At least one of the pair of gripping members is provided so as to be movable in the linear direction, and the abutting tool disposed on the gripping member is moved relative to the gripping member in the linear direction at one end of the side that abuts the assembly component. a holding member that is held immovably; and c, the holding member is urged by a spring member to move toward the other end, and a contact tool held by the holding member is pressed against the holding member. This prevents the abutting tool from freely rotating when the assembly part is gripped, and at the same time prevents the abutment tool from rotating freely when the assembly part is engaged with the to-be-assembled part and a force is applied. The abutment tool is configured to allow the abutment tool to rotate together with the assembly part about the axis in the linear direction without causing relative movement between the assembly part and the abutment tool. It is characterized by having a rotation resistance means for applying a predetermined constant rotation resistance.

Function In such a gripping device, a pair of gripping members are brought relatively close to each other, and the assembled part is attached to the gripping member through a contact tool that is rotatably disposed about an axis in a linear direction. is gripped, and in this state, the assembly part is conveyed to the assembly position and engaged with the assembly target part. At least one of the abutting tools is attached to the gripping member via a holding member, and when the holding member is biased toward the other end by the spring member of the rotational resistance imparting means, the abutment tool is gripped. Rotational resistance is provided by the friction between the members being pressed against each other. Therefore, the free rotation of the abutting tool is prevented, and the assembly component is conveyed in a predetermined constant posture, and is engaged with the component to be assembled in a correct posture.

When the gripping device is further moved while gripping the assembly part at the assembly position, the assembly part engaged with the assembly part is rotated around the linear axis together with the abutting tool. , is assembled to the part to be assembled. The rotational resistance applied to the abutment tool by the rotational resistance imparting means is such that the rotational resistance is applied to the abutment tool without causing any relative movement between the assembled parts and the abutment tool.
Since the abutment tool is set to rotate together with the assembly part, the rotation center of the assembly part does not move, and the rotation center of the assembly part is determined by the rotation center of the abutment tool. Therefore, it is always maintained constant without changing depending on the gripping conditions or the like. Therefore, the parts to be assembled can always be properly assembled to the parts to be assembled, and poor assembly due to movement or deviation of the center of rotation is prevented.

Effects of the invention As described above, according to the gripping device of the present invention, it is possible to successfully assemble the parts to be assembled while gripping the parts to be assembled, so that a separate device can be provided only for assembly. There's no need to. In addition, since such a gripping device rotates and assembles the parts to be assembled by engaging them with the parts to be assembled, the rotational speed and rotation of the abutting tool cannot be controlled, as in the case of forcibly rotating the parts to be assembled. There is no need to control the amount with high precision, and only the gripping device can be moved and assembled, and the control during assembly is simple and the device can be constructed at low cost.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

FIG. 1 and FIG. 2 are a plan view and a side view of this embodiment, respectively. In these figures, 10 is a chuck body fixedly attached to the tip of a robot arm 12, and a pair of gripping members 14 and 16 are provided on both sides of the chuck body 10, respectively, and protrude forward. It is being These gripping members 14 and 16 are driven in the left-right direction in FIG. 1 by an air cylinder (not shown) disposed within the chuck body 10, so that they can approach and separate from each other.

The tips of the gripping members 14 and 16 include the approach,
A contact member 1 is placed on a straight line in the separating direction.
8 and 20 are arranged facing each other. The abutting member 18 includes a shaft 24 inserted into a circular hole 22 formed at the tip of the gripping member 14 from the inside, that is, from the gripping member 16 side, so as to be movable in the linear direction, and a head 26 of the shaft 24. and a urethane resin 28 fixed to the shaft 24.
is rotatable about its axis by a bearing 30 inserted between the head 26 and the gripping member 14. The urethane resin 28 is for preventing scratches or slipping between the assembled parts when gripping them. The head 26 and the urethane resin 28 correspond to a contact tool, and the portion of the shaft 24 excluding the head 26 corresponds to a holding member. In this embodiment, the holding member and the abutment tool are integrally constructed and are configured to rotate together around their axis.

A nut 32 is screwed onto the tip of the shaft 24 that protrudes outward from the gripping member 14, that is, the other end opposite to the head 26, and the washer 34 and the gripping member are prevented from being pulled out by the nut 32. 1
A spring 36 is inserted between the spring 4 and the spring 36.
The spring 36 is arranged in a compressed state, and based on this biasing force, the head 2 of the shaft 24
6 is pressed against the bearing 30, the shaft 24, the head 26 and the urethane resin 28
A predetermined constant rotational resistance is applied to the abutment tool consisting of the following. This rotational resistance is determined by the nut 32
The screwing position of this nut 32 can be adjusted by changing the screwing amount of the lock nut 38.
It has come to be defined by. In this embodiment, the spring 36, the washer 34, and the nuts 32, 38 constitute a rotational resistance imparting means, and the spring 36 corresponds to a spring member that biases the shaft 24 toward the other end.

The abutment member 20 side is configured in exactly the same way as the abutment member 18 side, so the same reference numerals are given and the explanation will be omitted.

Next, the operation of the gripping device configured as above will be explained. In the following description, a case will be described in which the cage 40 of a front axle joint of an automobile is gripped and assembled to the inner 42 as one usage mode of the present device.

First, with the pair of gripping members 14 and 16 separated from each other by an air cylinder (not shown), the robot arm 12 is driven so that the cage 40 as an assembly part is positioned between them. Next, the gripping member 1 is
By bringing the cages 4 and 16 close to each other, the cage 40 is pinched and held in a straight line between the abutment members 18 and 20 disposed at the tips of the cages 4 and 16. The cage 40 has a cylindrical shape, and is gripped by the abutting members 18 and 20 in a predetermined constant posture from a direction perpendicular to the center line of the cylindrical shape.

Since the urethane resin 28 is provided at the tips of the contact members 18 and 20, there is no fear that the cage 40 will be scratched or slip and fail to be gripped when gripped. Further, although the contact members 18 and 20 are attached to the contact members 18 and 20 so as to be rotatable around the axis by bearings 30, that is, to be rotatable around the axis in the linear direction, rotational resistance is provided by the spring 36. Therefore, such a contact member 1
The cage 40 held between the cages 8 and 20 cannot freely rotate around the axis in the linear direction.
Note that when the cage 40 is gripped, the head 26 of the shaft 24 is pressed against the bearing 30 due to the reaction force. A rotational resistance based on is given. The screwing position of the nut 32 is set in consideration of this reaction force.

By driving the robot arm 12 while gripping the cage 40 in this manner, the cage 40 is transported to a predetermined assembly position.
At the assembly position, the inner 42, which is a part to be assembled into which the cage 40 is to be assembled, is fixed in a predetermined constant posture, and by advancing the robot arm 12 to the left in FIG. A lower end portion of the inner member 40 is engaged with one of a plurality of convex portions 44 provided on the outer peripheral portion of the inner member 42 . Therefore, when the robot arm 12 is further advanced, a force in the right direction indicated by arrow A is applied to the cage 40, and the pair of gripping members 1
It is rotated in the counterclockwise direction shown by arrow B around the part gripped by 4 and 16,
It is assembled to the inner 42 as shown by the two-dot chain line.

Here, since the cage 40 is held between the abutting members 18 and 20 that are rotatably attached around the axis, when a force in the direction shown by arrow A is applied to the lower end, the abutting members 18 and 20 Although the members 18 and 20 are rotated about a linear axis, they are not relatively moved in the direction of the applied force, ie, in the right direction as indicated by arrow A.
In particular, in this embodiment, the urethane resin 28 is fixed to prevent slipping between the abutting members 18, 20 and the cage 40, so such movement is effectively avoided. The screwed-in position of the nut 32 is such that the rotational resistance imparted to the abutting members 18, 20 by the spring 36 is
Contact member 1 in a state where cage 40 is gripped
8, 20, while preventing the free rotation of the cage 4.
0 is engaged with the inner 42 and force is applied, the abutting members 18, 20 are moved without relative movement between the cage 40 and the abutting members 18, 20.
The abutting member 1 is configured such that the abutting member 1
It is set in consideration of friction between 8, 20 and the cage 40, etc. Further, since the rotation center of the cage 40 is defined by the rotation centers of the abutting members 18 and 20, it does not vary depending on the gripping conditions or the like.

In this way, the gripping device of this embodiment grips the cage 40 via the abutment members 18 and 20 that are rotatably attached to the gripping members 14 and 16 about their axes. When a force is applied to the cage 40, the abutment member 1
Since the cage 40 is rotated only around the axes 8 and 20, it is possible to suitably assemble the cage 40 onto the inner 42 while gripping the cage 40 that has been transported to the assembly position. Therefore, there is no need to provide a special device for assembling the cage 40 to the inner 42.

Further, in this embodiment, rotational resistance is applied to the contact members 18 and 20 by the spring 36, and the cage 4
Since free rotation of the cage 40 is prevented, there is no fear that the posture of the cage 40 will change when the cage 40 is gripped and transported to the assembly position. Therefore. Due to the change in the posture of the cage 40, the inner 42
It will not become impossible to assemble the parts.

Furthermore, since the rotational resistance of the abutting members 18 and 20 can be adjusted by changing the screwing position of the nut 32, it can be adjusted depending on the gripping conditions, such as gripping the assembled parts in a cantilevered manner. There is an advantage that the rotational resistance can be easily adjusted.

On the other hand, the gripping device of this embodiment has a cage 4
Since the cage 40 is rotated and assembled by engaging the cage 40 with the inner 42, the contact member 1
There is no need to control the rotational speed and amount of rotation at 8 and 20 with high precision in relation to the movement of the gripping device, and only the gripping device can be moved and assembled, and the control during assembly is easy. The device can be constructed at low cost.

Although one embodiment of the present invention has been described above in detail based on the drawings, the present invention can also be implemented in other forms.

For example, in the above embodiment, the cage 40 is
Although the explanation has been made regarding the case where the inner 42 is assembled to the cage 40, it is also possible to grip one protrusion 44 of the inner 42 and rotate it around the protrusion 44 while assembling the inner 42 to the cage 40. Further, the present invention can be similarly applied to a gripping device that grips other parts to be assembled and assembles them to a predetermined member to be assembled.

Further, in the embodiment, the pair of gripping members 14, 1
6 are each driven by an air cylinder, but only one of the gripping members 14 or 16 is driven to approach or separate from the other gripping member 16 or 14 that is fixedly provided. It is also possible to use a drive source other than the air cylinder. Furthermore, it is also possible to rotate the pair of gripping members 14 and 16 so that their tips approach or separate.

Further, in the embodiment described above, rotational resistance is applied to the contact members 18 and 20 by the spring 36, but rotational resistance can also be applied using other spring members such as a dish-shaped spring. In the above embodiment, the rotational resistance can be adjusted by changing the screwing position of the nut 32, but it is not necessarily necessary to adjust the rotational resistance in this way. It is only necessary that the rotational resistance is applied to the rotational resistance at a constant level, and it is also possible to apply rotational resistance to only one of the contact members 18 and 20.

Further, in the embodiment described above, the urethane resin 28 is provided at the contact member portion with the cage 40, but it goes without saying that other friction members or the like may also be provided. There is no problem even if they are brought into contact with each other.

Although no other examples are given, the present invention can be implemented with various modifications and improvements based on the knowledge of those skilled in the art without departing from the spirit thereof.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view showing a state in which a gripping device according to an embodiment of the present invention grips an assembled part. 2 is a side view of the gripping device of FIG. 1; FIG. 14, 16...Gripping member, 18, 20...Abutting member, 24...Shaft (holding member), {26...
Head, 28... Urethane resin, } (abutting tool), {32
... Nut, 34 ... Washer, 36 ... Spring (spring member) 38 ... Lock nut}, (Rotational resistance imparting means), 40 ... Cage (assembly part), 42 ...
...Inner (parts to be assembled).

Claims (1)

[Claims for Utility Model Registration] By bringing the pair of gripping members relatively close together, the assembled parts are pinched and gripped from a straight line direction, and the parts are conveyed to the assembly position and placed at the assembly position. A gripping device for assembling the part to be assembled by engaging the part to be assembled, rotating the part to be assembled while gripping the part, and rotating the part to be assembled to the part to be assembled, the gripping device comprising: a pair of abutting tools disposed at a portion of the gripping member that abuts the assembly component so as to be rotatable about an axis in the linear direction while gripping the assembly component; The abutment tool is provided on at least one side so as to be movable in the linear direction, and holds the abutment tool disposed on the gripping member at one end of the side that abuts the assembly part so as not to be relatively movable in the linear direction. a holding member; the holding member is urged by a spring member to move toward the other end; and the assembly part is moved by pressing an abutting tool held by the holding member against the gripping member. When the assembly part is engaged with the to-be-assembled part and a force is applied, the connection between the assembly part and the applicable joint is prevented. Rotation that applies a predetermined constant rotational resistance to the applicable fitting so as to allow the applicable fitting to rotate about the linear axis together with the assembled parts without causing any relative movement therebetween. A gripping device comprising: a resistance imparting means;