JPH0776396A - Clamping device - Google Patents

Abstract

PURPOSE:To enable securely holding a heavy container and prevent a excessive deforming of a flexible container by providing rocking parts and a stopper, the rocking parts being provided on the side of clamp shafts and clamp arms respectively and designed to act in conjunction with them and the stopper being designed to stop the arms from acting during their closing action. CONSTITUTION:Reinforcing rods 37A, 37B are fixed respectively to the forward ends of rocking arms 36A, 36B which project radially from the lower ends of a pair of clamp shafts 26A, 26B. One clamp arm is attached to the clamp shaft 26B and the reinforcing rod 37B and another clamp arm is attached to the clamp shaft 26A and the reinforcing rod 37A. The rocking arms 36A, 36B provided in a pair face parts partly forming rocking parts 36a, 36b which spread radially outward with a stopper 39 disposed therebetween. While the two rocking arms 36A, 36B, that is, the two clamp arms, are in rocking motion for the closure from the full-open position to the full-closed, the stopper comes in touch with the rocking parts 36a, 36b and stops them from their closing action.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp device having a pair of clamp arms for holding a container.

2. Description of the Related Art Conventionally, as a clamp device, a rotary member rotatably provided on a frame, and a pair of clamp shafts pivotally supported at positions at equal intervals in the circumferential direction of the rotary member and mutually reversely rotated. A pair of clamp arms provided on each clamp shaft and opened / closed by its rotation operation, a return spring for urging the pair of clamp arms in a closing direction, and a pair of clamp arms against the return spring. It is known that a drive mechanism for performing a spreading operation is provided. In this type of clamp device, a container is supplied between the pair of clamp arms in a state where the pair of clamp arms are expanded and opened against the return spring by the drive mechanism, and then the return spring is repelled. The pair of clamp arms is closed by force to grip the container.

The elastic force of the return spring is required to be large enough to grip the container. For example, when the container made of glass and the container made of plastic are used in combination, the return spring described above is used. If the resilience of the spring is set to a size sufficient to grip a glass container, the resilience becomes too large when gripping a plastic container, which may cause excessive deformation of the container. . On the contrary, if the elastic force of the return spring is set to a value large enough to hold a lightweight plastic container, the elastic force is too small to hold a heavy glass container. Was sometimes insufficient. In view of such circumstances, the present invention provides a clamping device that enables a heavy container made of glass or the like to be gripped with a sufficient gripping force and a soft container made of plastic or the like to be gripped without excessive deformation. It is provided.

That is, according to the present invention, in the above-described clamp device, a swinging portion that operates integrally with the clamp shaft and the clamp arm is provided, and the rotary body is provided with the pair of clamps. A stopper is provided to stop the closing operation of the clamp arm by contacting the swinging portion during the closing operation in which the arm is swung from the fully open position to the fully closed position. Further, if necessary, an adjusting mechanism for moving the stopper to change the contact position between the stopper and the swinging portion may be provided.

According to the above construction, the pair of clamp arms are closed by the elastic force of the return spring to hold, for example, a plastic container. During the closing operation, the clamp shaft and the clamp arm are held. The oscillating portion that operates integrally with the stopper comes into contact with the stopper to stop the closing operation. Therefore, even if the elastic force of the return spring is sufficiently large, the pair of clamp arms can grip the plastic container without excessively deforming it. On the other hand, for example, in the case of gripping a heavy glass container, if the diameter of the grip of the glass container is equal to or larger than the diameter of the grip of the plastic container, more accurately When the glass container can be gripped before the moving part comes into contact with the stopper, the glass container can be reliably gripped by the sufficiently large elastic force of the return spring without any change. On the other hand, when the rocking portion comes into contact with the stopper before the pair of clamp arms grips the glass container, by removing the rocking portion or the stopper or moving the stopper by the adjusting mechanism,
It is possible to surely hold the glass container by the elastic force of the sufficiently large return spring.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. In FIG. 1, reference numeral 1 is a capper (see FIG. 2) for capping a container, and the container 3 conveyed by the conveyor 2 is a timing screw (not shown). Is synchronized with the rotation of the capper 1, is carried into the capper 1 by the supply side star wheel 4, and is clamped and fixed by the clamp device 6. The container 3 gripped by the clamp device 6 is conveyed as the rotating body 7 constituting the capper 1 rotates in the counterclockwise direction, and the container 3 is capped with the cap during that time. And the container 3 with the cap capped is the above-mentioned clamp device 6
After the grip by is released, it is discharged onto the conveyor 2 by the discharge side star wheel 8. As shown in FIG. 2, the capper 1 includes a fixed shaft 11 fixed to a frame 10 in the vertical direction, and a rotary shaft 12 is rotatably provided on the outer periphery of the fixed shaft 11 from an intermediate portion to a lower portion. The shaft is supported so that the rotating shaft 12 can be rotationally driven in one direction by a motor (not shown). The rotating body 7 includes a first disc 13 fixed above the rotating shaft 12.
And a rotary table 14 fixed below, and a second rotary table 14 connected above the first disc 13 via a plurality of rods 15.
And a disc 16. The shaft of the second disc 16 is rotatably supported on the upper end of the fixed shaft 11. A plurality of spindles 17 are arranged vertically at equal intervals on the outer peripheral portion of the first circular plate 13. Each spindle 17
A first spindle 17A having a spline formed on the inner peripheral surface of the cylindrical body and a second spindle 17B spline-fitted to the first spindle 17A are provided, and the upper end of each second spindle 17B is provided with a second disc. Each of them is connected to a servomotor 18 (FIG. 2) attached to the unit 16. On the other hand, the bracket 2 is provided at the central portion in the axial direction of each first spindle 17A.
The one end of the bracket 20 is rotatably attached, and the other end of the bracket 20 is attached to a guide rod (not shown) provided in parallel between two adjacent rods 15 so that the bracket 20 can move up and down. I try not to rotate with it. Then, a cam follower 21 is attached to each bracket 20, and each cam follower 21 is engaged with an elevating cam 23 fixed to the fixed shaft 11 via an inverted cup-shaped cover 22, so that the elevating and lowering motion is performed as the rotating shaft 12 rotates. The first spindle 17 by the cam 23
A can be raised and lowered. further,
A capping head 24 is attached to the lower end of each of the first spindles 17A, and when the second spindle 17B is rotated by the servo motor 18, the first spindle 17A spline-fitted to the second spindle 17B. Rotate the capping head 24 via
The cap 25 held by the capping head 24 can be capped on the container 3.
The capping head 24 is composed of, for example, a conventionally known air chuck type capping head, and can hold the cap 25 when compressed air is supplied from a compressed air source (not shown) through an electromagnetic valve. You can do it. Next, as shown in FIGS. 1 and 2, the same number of the above-described clamping devices 6 as the capping heads 24 are provided at the outer peripheral portion of the lower rotary table 14 constituting the rotary body 7 at equal intervals. Each clamp device 6
Is a pair of clamp shafts 26A and 26B vertically supported on the rotary table 14 and the clamp shafts 26A and 26B.
Gears 27, 27 attached to the two gears 2
By engaging 7 and 27 with each other, when one clamp shaft 26A is rotated in the forward and reverse directions, the other clamp shaft 26B can be rotated in the reverse direction. A pair of clamp arms 28A and 28B is attached to each of the pair of clamp shafts 26A and 26B so as to rotate integrally with each of the clamp shafts. Therefore, by rotating the pair of clamp shafts 26A and 26B in opposite directions via the gears 27 and 27, the pair of clamp arms 28A and 28B can be opened and closed. One end of a swing lever 30 is fixed to the lower end of one clamp shaft 26A of the pair of clamp shafts 26A and 26B, and the other end of the swing lever 30 is a cam follower 32 that constitutes a cam mechanism 31. Is installed. The return spring 3 is provided between each swing lever 30 and the rotary table 14.
3, the swing lever 30 is moved in one direction by the return spring 33, that is, the clamp shaft 26A,
The clamp arms 28A and 28B are rotationally biased in a direction of being closed via 26B. The cam mechanism 31 constitutes a drive mechanism for expanding and operating the pair of clamp arms 28A, 28B against the return spring 33. The cam mechanism 31 includes a cam member 34 fixed to the frame 10. I have it. Then, the return spring 33 urges the swing lever 30 in the one direction described above to move the cam follower 32 to the cam member 3.
4 is engaged with the outer peripheral cam surface. Therefore, by swinging the swing lever 30 in the opposite direction against the return spring 33 by the cam member 34, the clamp arms 28A and 28B can be opened. next,
The lower ends of the pair of clamp shafts 26A, 26B are connected to one ends of swinging arms 36A, 36B projecting outward in the radial direction. Reinforcing rods 37A and 37B arranged in parallel with 26A and 26B are fixed. Then, one clamp arm 28A is attached across one clamp shaft 26A and the reinforcing rod 37A, and the other clamp shaft 26A is attached.
And the other side of the reinforcing rod 37B and the other clamp arm 2
8B is attached. As shown in FIG. 4, a part of the facing surfaces of the pair of swing arms 36A, 36B facing each other has a swing portion 36a formed in an inverted V shape so as to spread outward in the radial direction. 36b, both swing parts 3
A stopper 39 is arranged between 6a and 36b. The stopper 39 is provided for each of the pair of swing arms 36A, 36A.
B, and thus each pair of clamp arms 28A, 28B, abuts the rocking portions 36a, 36b during a closing operation in which the clamp arms 28A, 28B are rocked from the fully open position to the fully closed position.
The closing operation of A and 28B can be stopped before they are in the fully closed position. Each stopper 3 above
9 is moved in the radial direction of the rotating body 7 by the adjusting mechanism 40, thereby changing the abutting positions of the stoppers 39 and the swinging portions 36a and 36b, and the clamp arms 28A and 28B. It is possible to adjust the position where the closing operation of the is stopped. As shown in FIG. 3, the adjusting mechanism 40 includes a ring-shaped cam member 41 that surrounds the center of rotation of the rotary table 14 and is rotatably provided on the rotary table 14.
The sector gear 42 is integrally provided above the. The sector gear 42 includes a gear 44 attached to the lower end of the drive shaft 43.
And the drive shaft 43 is engaged with the first disc 1
3 (see FIG. 2) and a support block 45 fixed to the rotary table 14 are rotatably supported. And Figure 2
As shown in FIG. 4, a motor 4 having a gear 46 attached to the upper end of the drive shaft 43 and fixed to the gear 46 on the first disc 13
The drive gear 48 of No. 7 is meshed. Therefore, if the drive gear 48 is rotated in the forward and reverse directions by the motor 47,
Drive shaft 43, gear 46, gear 44 and sector gear 42
The cam member 41 can be rotated forward and backward with respect to the turntable 14 via the. As shown in FIG. 3, a ring-shaped plate 50 is fixed to the upper surface of the rotary table 14, and the same number of slide members 51 as the clamp devices 6 are arranged on the plate 50.
Each slide member 51 is engaged in a guide groove 52a of a guide member 52 arranged and fixed in the radial direction of the plate 50, and is reciprocally guided in the radial direction of the rotary table 14 by each guide member 52. ing. A cam follower 53 is attached to each of the slide members 51, and a cam groove 41a formed obliquely in the cam member 41.
By engaging the cam followers 53 with each other (see FIG. 4), when the cam member 41 is rotated forward and backward with respect to the rotary table 14, the slide members 51 can be moved back and forth all at once. I am trying. Further, a cylinder 54A is fixed to each of the slide members 51 toward the outside in the radial direction of the rotary table 14, and a piston rod 54B provided in each cylinder 54A so as to move back and forth is provided in each cylinder 54A. Spring 55 provided
Is urged toward the center side in the radial direction and is held at the sliding end position. The above-mentioned stopper 39 is attached to the tip of each piston rod 54B. At this time, each of the stoppers 39 is formed in a cylindrical shape, and both sides of the stoppers 39 are formed on the swinging portions 36a of the swinging arms 36A and 36B.
36b (see FIG. 4), the stopper 3
9 does not rotate about the axis of the piston rod 54B. In the above configuration, for example, when the plastic container 3 is loaded onto the rotary table 14 of the capper 1 via the supply-side star wheel 4, the pair of clamp arms 28A and 28B are returned to the return spring by the cam mechanism 31 described above. It is in the fully open position against 33. In this state, the pair of clamp arms 2
When the container 3 is carried in between the 8A and 28B, the pair of clamp arms 28A and 28B move the return spring 33.
Then, the container 3 is swung in the closing direction to grip the container 3. At this time, the pair of clamp arms 28A,
When 28B holds the container 3 while pressing and deforming the plastic container 3 by a predetermined amount, the rocking portions 36a and 36b of the rocking arms 36A and 36B are operated integrally with the pair of clamp arms 28A and 28B. Contacts the stopper 39 interposed therebetween, so that the clamp arms 28A and 28B are not closed by the stopper 39 and the container 3 is not deformed more than necessary.
On the other hand, the capping head 24 is held at the rising end position by the elevating cam 23, and in that state, the cap 25 is supplied to and held by the capping head 24 by the cap supply mechanism (not shown). When the cap 25 is supplied to and held by the capping head 24,
The capping head 24 is rotated by the servo motor 18 and is lowered by the lifting cam 23,
The held cap 25 is capped on the mouth of the container 3. After this, the cap 2 by the capping head 24
When the holding force of 5 is released and the capping head 24 is raised, the clamp arms 28A and 28B are opened by the cam mechanism 31 to release the grip of the container 3 and the container 3
Are discharged onto the conveyor 2 by the discharge side star wheel 8. Next, when the type of the container 3 is changed and it is necessary to expand the closing stop position of the clamp arms 28A and 28B for gripping the container 3, the motor 47 of the adjusting mechanism 40 is started and the drive gear 48 is activated. , The cam member 41 is rotated in one direction with respect to the rotary table 14 via the gears 46, 44, and the sector gear 42, and the slide members 51 are simultaneously moved in a radial direction by a predetermined amount via the cam grooves 41a of the cam member 41. Just move it inward. At this time, since the rocking portions 36a and 36b of some of the rocking arms 36A and 36B are separated from the stopper 39, the stopper 39 is retracted inward in the radial direction integrally with the slide member 51. Become. On the other hand, the stopper 39, which is held in contact with and sandwiched by the swinging portions 36a and 36b, particularly the swinging portions 36a and 36b.
Since the contact surface with the stopper 39 has an inverted V shape, it cannot be easily moved inward in the radial direction.
In this case, the cylinder 54A is attached to the slide member 51.
However, the stopper 39 and the piston rod 54B provided with the stopper 39 bend the spring 55 and stay in the original position. The stopper 39 rotates the rotating body 7 once to open the clamp arms 28A and 28B and the swing arms 36A and 36B by the cam mechanism 31, thereby causing the spring 55 to move.
It is possible to return to the non-actuated position with respect to the cylinder 54A by the elastic force of the
Position adjustment can be completed. According to such a configuration, the stoppers 39 are directly attached to the slide member 51, and the stoppers 39 engaged with the swinging portions 36a and 36b formed in the inverted V shape are moved to the swinging portions 36a and 36b.
It is not necessary to increase the strength of each member constituting the adjusting mechanism 40 or to increase the output of the motor 47, as compared with a structure in which the members are pushed back and expanded inward in the radial direction all at once. Can be manufactured. For the adjustment work described above, the type of the container 3 is changed and the container 3 is changed.
When it is necessary to reduce the closing stop position of the clamp arms 28A and 28B for gripping, the cam member 49 may be rotated by the motor 47 in the direction opposite to that described above. In this case, since the stoppers 39 move forward toward the open sides of the swinging portions 36a and 36b formed in the inverted V shape, all the stoppers 39 must be moved forward all at once to complete the position adjustment. You can In the above embodiment, swing arms 36A and 36B are provided on the clamp shafts 26A and 26B, and swing portions 36a and 3B are provided on both of them.
Although 6b is provided, either one may be omitted.
In this case, it is obvious that the stopper 39 does not necessarily have to move in the radial direction of the turntable 14. In addition, the swinging portion includes clamp arms 28A and 28A.
It is also possible to provide in B.

As described above, according to the present invention, a heavy container made of glass or the like can be gripped with a sufficient gripping force, and a soft container made of plastic or the like can be held without excessive deformation. The effect that it can be grasped is obtained.

[Detailed Description of Drawings]

FIG. 1 is a schematic plan view showing an example of the present embodiment.

FIG. 2 is a sectional view taken along the line 〓-〓 of FIG.

FIG. 3 is an enlarged view of a main part of FIG.

4 is a cross-sectional view taken along the line 〓-〓 of FIG.

[Explanation of sign]

DESCRIPTION OF SYMBOLS 1 ... Capper 3 ... Container 6 ... Clamping mechanism 7 ... Rotating body 13 ... 1st disc 14 ... Rotary table 16 ... 2nd disc 26A, 26B ... Clamping shaft 28A, 28B ... Clamping arm 31 ...
Cam mechanism 36A, 36B ... Swing arm 36a, 36b ...
Oscillating part 39 ... Stopper 40 ... Adjustment mechanism 41 ... Cam member 41a ... Cam groove 51 ... Slide member 53 ... Cam follower 54A ... Cylinder 54B ... Piston rod 55 ... Spring

Claims (2)

[Claims] 1. A rotating body rotatably provided on a frame,
A pair of clamp shafts pivotally supported at equal intervals in the circumferential direction of the rotating body and mutually reversely rotated, and a pair of clamp arms provided on each clamp shaft and opened and closed by its rotating operation. A clamp device comprising a return spring for urging a pair of clamp arms in a closing direction, and a drive mechanism for expanding each pair of clamp arms against the return springs. A swinging portion that operates integrally with them is provided, and the pair of clamp arms abuts on the rotating body during the closing operation in which the pair of clamp arms is swung from the fully open position to the fully closed position. A clamping device, which is provided with a stopper for stopping the closing operation of the. 2. The clamp device according to claim 1, further comprising an adjusting mechanism for moving the stopper to change a contact position between the stopper and the swinging portion.