JPH0748361Y2 - Work gripping mechanism of work handling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a work handling device used for transferring a work. More specifically, the present invention relates to a work gripping mechanism of a work handling device suitable for gripping and releasing an annular work on a ball bearing or the like.

[Conventional technology]

As an example of the work handling device, there is known a device that measures the outer diameter of a ball bearing and sorts and sorts them by tolerance. Such an apparatus includes a work hand for transferring a ball bearing which is a work.
This work hand takes out the ball bearings with different diameters stored in the stocker one by one, puts them on the measuring table, and sorts the ball bearings whose outer diameters have been measured on the measuring table according to the measurement results. Operates to transfer to a department. The work hand performing such an operation is provided with three gripping claws for gripping the outer circumference of the ball bearing, and these claws are linearly moved reciprocally in the radial direction with respect to their centers, Thus, the ball bearing is gripped and released, and when the ball bearings having different diameters are handled, the movement start position of each claw can be changed.

As a mechanism for linearly driving the pawls for performing such a work gripping and releasing operation, a mechanism using a hydraulic or pneumatic cylinder is generally used.

[Problems to be solved by the device]

In such a drive mechanism, since the stroke amount of the working rod of the cylinder is fixed, in order to handle various ball bearings with different diameters, for example, it is possible to incorporate a large capacity cylinder. Will increase the device size. Further, the conventional mechanism requires a position control mechanism such as a sensor for controlling the moving position of the claw. Therefore, it is difficult to make the drive mechanism compact in size.

In view of such a point, an object of the present invention is to realize a work holding mechanism of a work handling apparatus which has a simple structure and is compact.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, in the present invention, a cam mechanism is used to linearly reciprocate a workpiece holding claw member. That is, in the work gripping mechanism in the work handling device of the present invention, a cam groove is formed in the rotating member, and a cam follower that slides in the cam groove is connected to a pawl support member capable of linear reciprocating motion. Is a curved line in which the rotation angle of the rotary member and the linear movement position of the claw support member are set to correspond one-to-one.

Further, the present invention particularly relates to a work holding mechanism in an annular work handling device such as a ball bearing, and this work holding mechanism uses a plurality of work holding claw members and a cam mechanism for these claw members. It is composed of a drive mechanism that linearly reciprocates. This drive mechanism has a cam groove formed in the rotating member and a pawl support member connected to a cam follower that drives the cam groove. The pawl support member approaches and separates from other pawl support members. It is supported so as to be linearly reciprocally movable in the direction. further,
The cam groove is set in a curved shape substantially along the Archimedean spiral.

[Operation] In the work holding mechanism having this configuration, when the rotating member is rotated by the motor or the like, the cam groove formed therein is rotated. The claw support member that is connected to the cam follower that slides in the cam groove is set to be capable of linear reciprocal movement, so when the cam groove rotates, it linearly moves in response to the linear movement. The position of the direction changes. Therefore, the claws supported by the claw support member also move linearly. Therefore, by controlling the rotation angle of the above member, the claw can be moved toward and away from the work, and the work can be gripped and released.

Here, when the cam groove is set in a curved shape along the spiral line of Archimedes, the relationship between the rotation angle of the rotating member and the linear movement position of the pawl is represented by a linear function. The correspondence is clear and the movement position of the claw can be easily controlled.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

Overall Structure FIGS. 1 and 2 show a ball bearing outer diameter measuring device to which the present invention is applied. Describing with reference to these drawings, the measuring apparatus 1 of the present example has an outer diameter measuring table 3 installed on the upper surface of a base 2, and the upper surface of the outer diameter measuring table 3 serves as a work mounting surface 3a. Has been done. Above the work mounting surface 3a, the work supply hand mechanism 4 for mounting the ball bearing W, which is a work, on the work mounting surface 3a, and the work W after the measurement is taken out from the mounting surface 3a. And a work recovery hand mechanism 5 for The work supply hand mechanism 4 and the recovery hand mechanism 5 are
It has the same structure and is supported on the lower surface of the vertical column 6 in a bilaterally symmetric state. The vertical column 6 is supported by an elevating mechanism 7 including vertically arranged pneumatic cylinders so that the vertical column 6 can be moved up and down.
It is supported by a state capable of reciprocating horizontally. Further, as can be seen from FIG. 1, a work recovery mechanism 9 is installed below the recovery hand mechanism 5 when the vertical column 6 reaches the right end shown by the solid line. On the other hand, as shown by an imaginary line in FIG. 1, a work supply mechanism 10 is installed below the supply hand mechanism 4 when the vertical column 6 reaches the leftmost position.

Here, FIG. 3 shows the movements of the work supply hand 4 and the recovery hand 5. The outline of the supply and recovery operations of the ball bearing will be described with reference to this figure and FIG. The vertical column 6 supporting the work supply and recovery hands 4, 5 is moved to the left end by the horizontal drive mechanism 8 (arrow A). In the state of reaching the left end, the work supply table 101 of the work supply mechanism 10 is located immediately below the work supply hand 4, and the ball bearing W2 for measuring the outer diameter is preliminarily placed there. ing. On the other hand, immediately below the work recovery hand 5, the work mounting surface 3a of the measuring table is located, and the ball bearing W1 whose outer diameter has already been measured is placed there.

As described above, after the hands 4 and 5 reach the left end elevated position I, the vertical support 6 is lowered by the elevating mechanism 7 (arrow B), and the work supply hand 4 and the collection hand supported there are. Reference numeral 5 is a gripping position II capable of gripping the ball bearings W1 and W2, respectively. After that, the ball bearings W1 and W2 are gripped by these hands. After being gripped, the vertical support 6 is lifted by the lifting mechanism 7, the hands 4, 5 holding the ball bearing are also lifted (arrow C), and the left end lifted position I is reached again. Next, the vertical support 6 is moved to the right end by the horizontal drive mechanism 8 (arrow D), and as a result, the supply hand 4 is located directly above the mounting surface 3a of the measuring table, and the other recovery hand 5 is the work recovery mechanism. This is a position directly above the collecting unit 91 of 9.

Thus, after the hands 4 and 5 reach the right end rising position III, the vertical column 6 is lowered by the lifting mechanism 7 (arrow E), and the hands 4 and 5 move the ball bearings held by them. Reach the open position IV where it can be opened. After this,
Each hand 4, 5 opens a ball bearing. As a result, the ball bearing W2 to be measured is mounted on the mounting surface 3a of the measuring table, and the ball bearing W2 that has already been measured is collected by the collecting mechanism side. After this, the strut 6 is raised again (arrow F), and both hands 4, 5 are set to the right end raised position III,
By repeating the above-described operation, the outer diameters of a large number of ball bearings are measured.

Work Supply Hand 4 The structure of the work supply hand 4 will be described with reference to FIGS. 4 and 5. The work supply hand 4 has a horizontal support plate 41 integrally attached to the lower surface of the vertical column 6, and the support plate 41 has three radiating pieces extending radially from the central position at equal angular intervals. 41a, 41b, 41c are provided.
A vertical column 42 penetrates through the center of the radiating piece, and at the lower end of the vertical column 42, a work holding plate 43 composed of three radiating pieces smaller than the radiating pieces 41a to 41c is provided. It is fixed horizontally.

Ball spline shafts 44a to 44c extending in parallel along the radiation pieces 41a to 41c are arranged below the radiation pieces 41a to 41c. These ball spline shafts 44a-44c are
Each outer end is supported by brackets 45a-45c hanging from the outer ends of the radiating pieces 41a-41c, and each inner end is supported by the outer periphery of the vertical column 42. The outer circumferences of the ball spline shafts 44a to 44c are slidable along the outer circumferences of the claw support members 46a to 4c, respectively.
6c is supported. Workpiece gripping claw members 47a to 47c are attached to the lower surfaces of the claw support members 46a to 46c, respectively, and these claw members are provided with a work holding surface 471 extending vertically downward. A work engaging surface 472 that extends horizontally from the lower end of the work holding surface toward the vertical column 42 is formed.

On the other hand, a rotating disk 48 is horizontally installed concentrically with the vertical column 42 between the ball spline shafts 44a to 44c and the support plate 41, and a bearing 49 is attached to the outer periphery of the vertical column 42. And is rotatably supported. The rotary disc 48 is formed with three cam grooves 48a to 48c. These cam grooves have a shape along the Archimedean spiral, and are formed with a phase of 120 degrees centering on the vertical column 42, respectively. FIG. 5 shows only the cam groove 48a. As shown in FIG.
It is formed over the range of 0 degrees. These cam grooves 48a
Within ~ 48c, cam followers 51a ~ 51c slidable along these are installed.
Legs hanging from the lower surfaces of 51a to 51c are screwed to the upper surfaces of the corresponding claw support members 46a to 46c, respectively.

Next, a circular internal gear 52 is concentrically fixed to the upper surface of the rotary disk 48, and a pinion 53 is meshed with the internal gear 52. The pinion 53 is fixed to the output shaft 541 of the servo motor 54, and the servo motor 5
4 is attached to the support plate 41 in a vertical state.
The rotation of the servo motor 54 is performed by the pinion 53 and the internal gear 52.
It is decelerated by the deceleration mechanism consisting of and transmitted to the rotating disk 48.

Configuration of Collection Hand 5 The configuration of the collection hand 5 is the same as that of the supply hand 4 described above, and thus the description thereof is omitted.

Work Gripping and Opening Operation Next, the gripping and opening operation of the ball bearing W by the work feeding hand 4 having the above configuration will be described. In the state of reaching the work gripping device II shown in FIG. 3, each claw member 47a of the work supply hand 4 is located at the outermost side,
It is open.

The claw member 47a in this state is in the position shown in FIGS. 4 and 5. In this state, when the motor 54 is driven to rotate the rotating disk 48 in the direction of arrow L in FIG. 5, the cam groove 48a formed in this rotating disk also rotates about the vertical column 6. As a result, the ball spline shaft 44
The position of the cam groove 48a intersecting with a gradually moves toward the center side. Therefore, the pawl support member 46a connected to the cam follower 51a sliding in the cam groove 48a moves toward the center along the ball spline shaft 44a. That is, the claw member 47a supported by the claw support member 46a also moves toward the center. The other two claw members 47b and 47c also move toward the center in the same manner.

In this way, when the three claw members 47a to 47c move toward the center, as shown in FIG. 6 and FIG. 7, their work holding surfaces 471 come to the outer ring outer peripheral surface Wa of the ball bearing W. The workpiece engaging surfaces 472 at the lower ends thereof are brought into contact with each other and engage with the lower end surface Wb of the outer peripheral surface of the outer ring of the ball bearing. Therefore, if the rotation angle of the rotary plate 48 is appropriately controlled according to the outer diameter of the ball bearing W, the state where the ball bearing W is gripped with a constant gripping force by these three claw members 47a to 47c is obtained. It is formed.

After gripping the ball bearing W, the work supply hand 4 moves to the work opening position IV, as described with reference to FIG. At the open position IV, the motor 54 is driven in the reverse rotation direction to rotate the rotating disk 48 in the reverse direction. As a result, the three claw members 47a to 47c return to the open position again, and the ball bearing W held by these is released.

Effects of Embodiments As described above, in the present embodiment, the rotational movement of the motor is converted into the linear movement of the claw member by using the cam mechanism having the cam groove having the shape along the Archimedean spiral. ,
In this way, the ball bearing, which is the work, is gripped and released. Therefore, such a drive mechanism can be made compact with a simple structure, as compared with a conventional drive mechanism that uses a hydraulic or pneumatic cylinder as the drive mechanism for the claw member. Further, by controlling the rotation amount of the cam groove, it is possible to perform the gripping and releasing operations of the ball bearings having different outer diameter dimensions. Further, the stroke amount of the claw member can be easily changed by attaching the rotary discs in which the cam grooves of different sizes are formed.

Here, in this example, the ball bearing is gripped from the outside by the three claw members, but conversely,
It is also possible to dispose the claw members in the inner ring of the ball bearing and then spread them to push them against the inner peripheral surface of the inner ring to grip the ball bearing. Further, in this example, the three claw members are moved, but, for example, by fixing one claw member and linearly moving only the remaining two claw members, the ball bearing gripping and It can also be opened.

Although the present invention is applied to a ball bearing measuring device in this example, it is needless to say that the present invention is applied to a device for handling other works. Further, the number of claw members for gripping the work is not limited to three. Similarly, as the shape of the cam groove, it is possible to use a spiral wire other than the above Archimedes spiral wire, and as such a curve, the rotation amount of the cam groove and the linear movement amount of the claw member are paired. It only has to correspond to one.

[Effect of device]

As described above, in the work gripping mechanism of the work handling device of the present invention, the rotation output of the motor or the like is converted into the linear reciprocating motion of the work gripping claw member by using the cam mechanism. The shape of the cam groove forming the cam mechanism is set to a curved shape in which the rotation amount and the linear reciprocating movement amount correspond one-to-one. Therefore, according to the present invention, it is possible to easily change the linear reciprocating movement amount of the pawl member by controlling the rotation amount of the cam groove or changing its shape and size. Compared to the mechanism, the mechanism for gripping a work having different dimensions can be made simple and compact.

[Brief description of drawings]

1 is a partial front view showing an outer diameter measuring device for a ball bearing according to an embodiment of the present invention, FIG. 2 is a partial plan view of the device of FIG. 1, and FIG. 3 is an operation of the device of FIG. 4 is a partially enlarged sectional view showing a portion of the work supply hand in the apparatus of FIG. 1, FIG. 5 is a partial arrow view of the portion shown in FIG. 4 from the side of arrow V, FIG. 6 is a partially enlarged view showing a part of the work supply hand in the work gripping state, and FIG. 7 is a partial arrow view of the part shown in FIG. 6 viewed from the arrow VII side. [Explanation of reference symbols] 1 ... Outer diameter measuring device, 2 ... Base, 3 ... Measuring stand, 4 ...
… Work supply hand, 5 …… Work recovery hand, 6 ……
Prop, 7 ... Lifting mechanism, 8 ... Horizontal drive mechanism, 9 ... Work recovery mechanism, 10 ... Work supply mechanism, 41 ... Support plate 42 ... Vertical support 43 ... Work holding plate 44a to 44c. Ball spline shaft 46a to 46c …… Claw support member 47a to 47c …… Claw member 48 …… Rotating disc 51a to 51c …… Cam follower 52 …… Internal gear 53 …… Pinion 54 …… Motor W, W1, W2 ……ball bearing.

Claims (1)

[Scope of utility model registration request] 1. A plurality of claw members for gripping a work, a support member supporting each of these claw members and being capable of linear reciprocating movement, and drive means for linearly reciprocating these supporting members. The drive means is connected to the rotating member, the curved cam groove formed in the rotating member, and the supporting member, and is slidably fitted in the cam groove. The cam groove has a shape, and the shape of the cam groove is set to be a curved shape along the spiral of Archimedes in which the rotation angle of the rotating member and the position of the support member in the linear reciprocating direction correspond one-to-one. The driving means causes the claw members to linearly reciprocate in the directions toward and away from each other with respect to their center positions to grip and release the annular work. Workpiece holding mechanism of a workpiece handling apparatus according to claim Rukoto.