JP2601475Y2 - Clamping device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp device for fixing an object such as a jig to a machine base.

[0002]

2. Description of the Related Art Conventionally, as a clamp device of this kind, as shown in FIG.
A clamp rod 31 engageable with a notch 2a formed on the object 2 and swings so that the clamp rod 31 is disengaged from the notch 2a in conjunction with a driving source 32. And a clamp unit 3 including a cam mechanism for moving forward and backward,
With the clamp rod 31 engaged with the notch 2a, the head of the clamp rod 31 is pressed against the outer surface of the attachment 2 to fix the attachment 2 to the machine base 1. Have been.

[0003] In more detail, the cam mechanism is
A swing arm 33 swinging around a pivot 33 a by a cylinder serving as a drive source 32, and a pivot 33 a
An eccentric boss 34 eccentrically provided for pivotally supporting the clamp rod 31, a contact member 35 linked to the cylinder 32, and a spring (not shown) via the contact member 35. 1A), the eccentric boss via the swing arm 33 when the cylinder 32 is extended from the clamped state shown in FIG. By the rotation of the clamp rod 34, the clamp rod 31 moves forward, and the head of the clamp rod 31 rises from the outer surface of the attachment 2 as shown in FIG.
Is tilted to swing the clamp rod 31 outward, and FIG.
As shown in (c), the clamp rod 31 is disengaged from the notch 2a and is unclamped. If the cylinder 32 is contracted from this state, the clamp rod 31 moves in the opposite direction to the above.
Returns to the state shown in FIG. 1A, and the mounted object 2 is clamped to the machine base 1.

The clamp unit 3 includes a clamp switch 3 for detecting the return of the clamp rod 31 to the clamp position in cooperation with a dog 37a attached to the clamp rod 31.
7 and an unclamping switch 38 for detecting the swing of the clamp rod 31 to the unclamping position in cooperation with a dog 38a attached to the clamp rod 31.

[0005]

In the above-described apparatus, when a gap is clear between the machine base 1 and the workpiece 2 or when there is a processing error in the clamp portion of the workpiece 2. ,
During the swinging of the clamp rod 31 from the unclamping position to the clamp position, the head of the clamp rod 31 interferes with a corner portion or the like of the mounted object 2, and the clamp rod 31 rotates the eccentric boss 34 without returning to the clamp position. As a result, it may be retracted to the machine base 1 side to reach the state shown in FIG. 1D, and the mounted object 2 may not be clamped correctly.

At this time, if the clamp switch 37 is not turned on, a clamp abnormality can be detected. However, even if there is a clamp abnormality, the clamp switch 37 may be turned on at some times. There is a possibility that an emergency such as detachment of the attached object may occur.

[0007] In view of the above, the present invention provides an apparatus which can prevent occurrence of an abnormal clamp in the above-mentioned conventional clamp unit as much as possible and can reliably detect the occurrence of an abnormal clamp. Its purpose is to do.

[0008]

In order to achieve the above object,
According to the present invention , a clamp rod that can be engaged with a notch formed in an attached object and a clamp rod that is engaged with a driving source are disengaged from the notch in a machine base for attaching the attached object. In a device provided with a clamp unit having a cam mechanism for swinging and reciprocating, a lock unit having a cylinder is fixedly mounted on the machine base, and the lock unit is interlocked with the cylinder in a direction orthogonal to the swing locus plane of the clamp rod. A movable rod to be moved forward and backward is provided, and a lock piece that can be locked is attached to a clamp position where the movable rod is engaged with the clamp rod and the clamp rod is engaged with the notch , and the clamp rod and the lock piece are clamped.
With the lever in front of the clamp position,
When the lock piece engages, move the clamp rod to the clamp position
When formed into a shape that produces a wedge action that presses against
Then, the lock unit is fitted to the swinging locus surface of the clamp rod.
Detection means to detect the movement of the lock piece to the matching position.
And wherein the digit.

[0009]

[0010]

The lock piece is advanced / retracted by a cylinder via a movable rod in a direction orthogonal to the swing locus plane of the clamp rod. If a clamping abnormality occurs, if the lock piece is minor, the lock piece is moved to the swing locus plane. When the clamp rod is moved to a position that matches with, the clamp rod is pushed into the proper clamp position by the wedge action and locked in this position.
If the clamp is not pressed into the
The lock piece does not move to a position that matches the swing locus plane,
An abnormal clamping is detected by a signal of the detecting means.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiment shown in FIGS. 2 to 4 is an embodiment of the present invention in a clamp device for mounting an object 2 such as a welding jig provided on the side of an assembling station of an automobile body to a machine base 1 in an upright posture. It is applied and the clamp unit 3
Are provided in a pair at the top and bottom.

The clamp unit 3 is the same as that shown in FIG. 1. The clamp rod 31 is swung and reciprocated on a horizontal plane via a cam mechanism by a cylinder 32 serving as a driving source, and the clamp rod 31 is laterally attached to the mounted object 2. The clamp rod 31 is disengaged from the formed notch 2a.

Further, the machine unit 1 has a clamp unit 3,
The lock unit 4 is provided so as to be located outside the arrangement portion 3. The lock unit 4 is provided with the clamp rod 3.
1 includes a movable rod 42 which is advanced and retracted by a cylinder 41 provided in the lock unit 4 in a direction perpendicular to the swinging trajectory plane, that is, in a vertical direction, and a pair of upper and lower clamp units 3, 3 Clamp rod 31, 31
A pair of lock pieces 43, 43 engageable with each other,
The two lock pieces 43 can be moved to a lock position corresponding to the swing trajectory surface of each clamp rod 31 and an unlock position above the lock pieces 43 within a pair of upper and lower guide grooves 1 a formed on the machine base 1. And Then, a spring 44 for biasing the movable rod 42 downward is extrapolated to the movable rod 42, and both lock pieces 43,
43 is biased and held at the lock position.

The cylinder 4 is coaxial with the movable rod 42.
1 may be provided, but in this embodiment, the cylinder 41 is offset from the movable rod 42 and the movable rod 4
2 was connected to the cylinder 41 via a connecting portion 45 integral with the upper lock piece 43.

The lock unit 4 includes a cylinder 41
And the connecting portion 45
Is provided, and a lock piece 43 is provided.
Is moved to the lock position when the limit switch 46
Was turned on.

In the clamp operation of the clamp unit 3, the lock piece 43 is moved to the unlock position in advance, and the lock piece 43 is moved to the lock position after the clamp operation of the clamp unit 3. In this case, the clamp rod 31 is moved in the clamp operation. When the clamp rod 31 does not return to the normal clamp position due to the head of the head interfering with the corner of the mounted object 2 and a clamp abnormality as shown in FIG. During the movement to the position, it comes into contact with the clamp rod 31. If the abnormality of the clamp is slight, the movement of the lock piece 43 of the clamp rod 31 having a circular cross section is determined.
A lock piece 43 is provided on the peripheral surface having a tangent line inclined with respect to the
A wedge that abuts and presses the clamp rod 31 toward the clamp position
The action occurs and the clamp rod 31 is pushed into the regular clamp position, and the clamp abnormality is eliminated. When the clamp rod 31 is not pushed into the clamp position and the clamp abnormality is not resolved, the lock piece 43 does not move to the lock position, and the limit switch 46 remains off. Therefore, the occurrence of the clamp abnormality can be reliably detected by the signal of the switch 46.

[0017]

[Effects of the present invention] As is clear from the above description, the present invention
According to this, even if a clamping abnormality occurs, a minor clamping abnormality that frequently occurs can be automatically eliminated , and if the clamping abnormality is not eliminated, this can be reliably detected, and the reliability of the apparatus is improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing the structure and operation of a clamp unit.

FIG. 2 is a side view of an example of the device of the present invention including the clamp unit of FIG. 1;

FIG. 3 is a plan view thereof.

FIG. 4 is a front view taken along the line IV-IV in FIG. 2;

[Explanation of symbols]

1 Machine stand 2 Attached object 2a
Notch 3 Clamp unit 31 Clamp rod 32
Drive source 4 Lock unit 41 Cylinder 42
Movable rod 43 Lock piece 46 Limit switch (detection means)

──────────────────────────────────────────────────続 き Continuation of the front page (56) Reference Jikken 62-28350 (JP, Y2) International Publication 92/18264 (WO, A1) (58) Fields investigated (Int. Cl. ⁶ , DB name) B23Q 3/06 301 B23Q 3/06 304

Claims (1)

(57) [Scope of request for utility model registration] A clamp rod capable of engaging with a notch formed in an object to be mounted on a machine base on which the object is mounted, and a clamp rod being disengaged from the notch in conjunction with a drive source. A lock unit having a cylinder is fixed to a machine base, and the lock unit is interlocked with the cylinder and interlocks with a swinging track surface of a clamp rod in a direction orthogonal to a swing locus plane of the clamp rod. The movable rod is provided with a lock piece which can be locked at a clamp position where the movable rod is engaged with the clamp rod and the clamp rod is engaged with the notch , and the clamp rod and the lock piece are closed.
Clamp with lamp rod in front of clamp position
When the lock piece engages with the rod, the clamp rod is
When it is formed into a shape that produces a wedge action that presses
In both cases, the lock unit
Detection means for detecting the movement of the lock piece to the matching position
Clamping device, characterized in that provided.