JPS61241507A - Clamp device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention generally relates to the application of two or more workpieces having internal bores aligned with each other in a desired relationship during the performance of a particular operation on the workpieces. This invention relates to a wire pin type clamp device used for temporary clamping purposes.

In particular, the present invention relates to devices of the positive release type, and more particularly to devices adapted for use in motor-driven automatic insertion and extraction tools.

BACKGROUND OF THE INVENTION In industry, particularly in the aerospace industry, it is common practice to provide simple mechanisms for temporarily clamping parts together in a desired relationship so that certain intermediate operations can be performed on the parts being manufactured. It is desirable to If relatively small diameter mating holes are formed in each of the parts to be clamped, these mating holes are stretched, then expanded and pushed back into the body, whereby each part is pinned. Clamping can be accomplished by the use of a body with a sliding cotter pin that is clamped integrally between the flared end of the retractable body and the retracted body. Once the intermediate operations on the workpiece have been completed, the equipment can be handled and used repeatedly for other jobs by reversing the procedure described above.

A typical application in which such clamping is performed is in the process of temporarily attaching parts of an aircraft fuselage to each other or to structural members, while simultaneously permanently riveting them together and constructing an assembly.

Typically, the springs used in these types of fasteners are constructed in two halves of the same type, each with a wedge-shaped or beveled surface on its inner surface that resists a portion of the spreader located inside. The axially retracted half-rest is configured to be pulled apart and spread outwardly.

Typically, the device further includes a housing of particular configuration, usually cylindrical, and hexahedral surfaces, into which the spring is retracted by a force applied to its half-end. For small size applications, this clamping force is provided by a coil spring that is compressed when the pin is withdrawn from the housing.

For larger operations or when greater clamping force is required, the pin is returned into the housing with a screw actuated by a hand tool such as a wrench to clamp the workpiece.

A typical example of the above-mentioned device configured as J: for use with European standard shells is disclosed in U.S. Patent Application No. 6, pending herewith.
No. 02,356.

Typically, the clamping device is provided with a first hexagonal tool gripping surface on the exterior surface of the housing to hold the device against rotation during the clamping process, and a first hexagonal tool gripping surface on the nut threaded onto the split spring extension. The hexagonal tool gripping surface of No. 2 is installed and configured such that when the nut rotates on its axis to the point where it contacts the tail of the housing, further rotation causes the pin to be retracted into the housing and a clamping force is exerted by the pin. has been done.

The simultaneous use of hundreds or even thousands of such devices on complex structures such as aircraft frames is common in high volume manufacturing, and the need for more automated insertion and withdrawal of clamp devices has increased. It has occurred. This problem was first solved by providing assembly workers with a motor-driven hand tool with a socket that matched the hexagonal head of the drive nut. By appropriately applying torque force from the motor to the driving nut, the spring can quickly and forcefully engage or withdraw the work piece.

However, in such power-driven applications, the high torque forces on the nut during clamping can cause the spring head to wedge into the workpiece, forcing the driving nut into the housing.
) The wedge force acting between the workpiece and the spring when separated from the workpiece is sufficient to strongly retain the spring within the workpiece, and it is often necessary to strike the device to remove the spring from the workpiece. A second problem arises, which is that it is very powerful.

This device retention problem is caused by the fact that when the driving nut is forced in the withdrawal direction, it engages the retaining device within the housing and exerts a relative axial force between the spring and the housing. It has been found that this problem can be solved by holding the nut in place within the housing of the device so that the spring is pushed out of the workpiece. In addition, the bolt is loosened for a distance equal to some screw advance before nut engagement occurs. A power-driven insertion tool creates additional rotational inertia to remove the wedged pin from the workpiece. It has also been found that it can encourage "pulling". An example of such a "positive release" pin-type clamp is beam (1,ee) US 8' [3.
No. 289,525.

However, such prior art does not lend itself well to more fully automated equipment and handling processes.

This J: Ut [In case of application of large amount of automated equipment,
It would be desirable to combine a motor-driven nut grasping tool with a housing holding tool into a single device, eliminating the need to separately restrain the housing during operation. Furthermore, the device is equipped with the above-mentioned features so that the operator (human or robot) can simply insert the rear end of the device into the tool, push the pin into the workpiece, actuate the tool, and achieve the clamping action. It is desirable to include these in one tool.

Furthermore, in order to remove the device, it is desirable that the operator simply place the tool on the rear of the equipped clamp, activate the station, and then pull the clamp out of the workpiece.

Prior art devices such as the Serli patent cited above are not suitable for this desired striation for the following reasons. That is, the tool gripping surfaces of the housing and the driving nut are usually hexagonal in shape to receive holding and/or driving tools such as the hexagonal driving sockets 1 to 1.

In both clamped and unclamped positions,
These tool gripping surfaces are arranged in such a haphazard manner that it is impossible for a tool with concentrically continuous holding and driving features to be easily inserted onto the rear of the device. Therefore, the operator has more flexibility in determining the radial orientation of the initial tool relative to the rear of the equipment, but also allows both the housing retaining surface and the nut driver to be in a precise relative 4T orientation relative to the rear of the equipment. It is the rotation that ensures this so that complete insertion of the tool is possible. This “out of mind”
The problem caused equipment tools to be placed incorrectly on the back of the device.
The correct relative angular position of the two surfaces is achieved and the tool grip 1Δ
The clamp is prevented from forming or releasing until the surfaces are properly engaged within the tool. Even if you try to operate the power-driven shell without proper alignment between the device and the shell, the result is wasted rotation of the motor without engagement or 1lIlfl12. Otherwise, harmful noise is generated between the tool and the equipment, resulting in the head of the driving nut being scraped and quickly worn out.

Therefore, it is independent of the relative angular orientation of the clamp member's housing and the tool gripping surface of the driving nut, and the hand-held motor-driven equipment tool that can be easily inserted into the equipment tool regardless of the orientation. It is desirable to provide a "universal" lamp that is compatible with There is currently a strong need within the industry for a universal lamp and clamp equipped tool that solves the problems described above.

Such a universal tool is disclosed in co-pending U.S. patent application Ser. The gripping surfaces of the housing holding tool and the nut driving gripping tool are adapted to a device having concentric cylindrical tool gripping surfaces. This selection of gripping tool surface shape avoids off-centering problems.

SUMMARY OF THE INVENTION Accordingly, one object of the present invention is to provide a positive release pin type clamping device having a tool gripping surface adapted for use with a motor-driven conniver-equipped tool.

Another object of the present invention is to provide a device that is operationally reliable and resistant to wear and tear due to repeated high load automated loading and unloading.

Yet another object is to provide a device that is easy to manufacture and inexpensive.

To accomplish this and other objectives, a main body having an external tool gripping surface adapted to be universally grasped by the tool to retain it regardless of its initial angular orientation with respect to the housing is provided. The clamp having a housing portion further includes a spring driving nut rotatably held within the housing and extending from the rear of the housing, the nut also having an initial position between the nut face and the driving tool. A ramp device is provided which forms an external tool gripping surface that is universally gripped by the driving operator regardless of its angular orientation. The drive nut also includes a full length threaded hole for engaging a threaded shaft extending from a stud that retains the spring fingers within the housing.

The stud is secured by rotation blocking means within the housing to prevent rotation of the stud and spring when the nut is rotated about its axis, so that the spring moves into and out of the housing without rotation. Between the fingers of the wire is a spreader plate 1 held at one end within the housing. The spreader plate 1 is held in the housing without translational movement or rotation due to the movement of the spring fingers relative to it. Therefore,
As the nut is rotated relative to the clamping device housing, each element of the wire bin moves axially relative to the spreader, causing ramp means integrally formed on the wire element to engage or disengage the spreader. The stripping thereby causes the wire elements to spread or compress together, thereby clamping or loosening the workpiece.

So constructed, the clamping device can be inserted into and handled by a suitably shaped power-driven insertion tool without problems resulting from misalignment or misalignment of the nut relative to the housing.

A more complete understanding of the improvements made by the present invention will become apparent to those skilled in the art upon reference to the following detailed description of the preferred embodiments of the invention and the accompanying drawings.

2. Embodiment In FIG. 1, an improved positive release wire spring type clamping device 10 for automatic insertion and withdrawal is mounted on a pair of workpieces 1.2 having concentric holes. is shown in cross section. The springs 12 are of the same type and each spring is provided with a workpiece gripping surface 16 arranged on its inner surface to grip the workpiece 1 when both springs are expanded. To spread the springs, the ramps 14 placed on each spring 12 are placed on the nose portion 20 of the spreader 18 placed between the springs so that each spring spreads the inner surfaces of each other by the flesh of the spreader 18. contact J
: The sea urchin spring 12 can be retracted into the clamping device 10 in the axial direction.

The spreader 18 is restrained from axial movement by T-shaped fingers 22 held within the body of the clamp 10.

Spring finger 12 is rigidly held at one end of a stud 24 having a threaded shaft 26 extending axially from the end opposite spring 12. The stud 24 is provided with a counter-rotating single stage 28, which in this case takes the form of a hexagonal nut face.

The stud 24 moves linearly in the axial direction within the housing without rotating due to the rotation of the driving nut 3o, which has a screw hole 31 that engages with the screw shaft 26. Driving nut 3
0 is rotatably held within the clamp pin by a flange portion 32 having a cylindrical shoulder 34 with a diameter greater than its tool gripping surface 36. This tool gripping surface 36 has a cylindrical shape, so that it can be inserted in any angular orientation between the nut 30 and a matching driving tool socket. The need for socket 1 to engagement features is eliminated.

The spring 12, spacing (J-18), stud 24, and drive nut 30 are all axially retained within an outer housing 38 of the clamping device. The clamp housing 38 is generally cylindrical in shape; The platform of the preferred embodiment is formed with a nose 40 which contacts the workpiece 1.2 and applies an axial force thereto.

The spring 12 is connected to an opening 42 in the nose 40 of the housing body 38.
A driving nut 30 extends axially from the clamp body through the housing 3, and a driving nut 30 is inserted into the housing 3 from the opposite end of the clamping device 10.
8 through opening 58.

The housing 38 is provided with three axially arranged retaining devices along its entire length. The first of these is an annular groove 44 that axially retains the T-shaped fingers 22 of the spacer 18. To achieve this retention, groove 44 is provided with a washer 48 disposed axially between first and second shoulders 45 and 46 formed in housing 38. The shoulder 46 is formed by rolling a flange on the housing 38 after inserting the warp 48 and spreader 18 into the first retaining member 44 of the preferred embodiment.

A second annular groove 50 is formed in the housing 38 in which the stud 24 moves axially. This second annular groove is provided with anti-rotation means for interlocking engagement with complementary anti-rotation means 28 of the stud 24. Therefore, although the stud 24 can be moved axially by rotation of the driving nut 30, rotation of the stud 24 (and thus of the spring 12 and the shirts 1-26) within the housing 38 is prevented.

In the preferred embodiment of FIGS. 1 to 5, the illustrated anti-rotation means 28.52 are simply hexagonal in cross-section. However, it will be obvious to those skilled in the art that this means may take any other suitable form, such as a key sliding in a groove.

A third annular groove 54 is arranged in the housing 38 towards the outer end of the clamping device 10 for rotatably holding the driving nut 30.

This nut retaining annular groove 54 is formed similarly to the spacer retaining groove 44 and has a retaining shoulder 56 at one end of the groove 54 located in the groove 54 opposite the nut retaining washer ν62.

The nut holding washer 62 is inserted into a washer holding annular groove 63 of the housing 38, and is held in place by rolling a flange 60 for winding the washer in place.

A thrust washer 64 is placed in the nut retaining groove 54 in an opposite direction and abutting the shoulder 56 .

This thrust washer 64 serves to axially retain the driving nut 30 and is also used for driving the nut 30 for which relative axial forces are transferred between the stud 24 and the housing 38 during installation of the clamp 10. It acts as a bearing surface, thereby preventing abrasion and wear between the mating surfaces of the non-rotating housing 38 and the rotating drive nut 30.

A nut 30 is mounted on the tool gripping surface 66 on the outside of the housing 38.
Similar to the tool gripping surface 36, a cylindrical conniversal smooth surface is provided. The outside diameter of the tool gripping surface 66 of the housing is, in the preferred embodiment, larger than the diameter of the tool gripping surface 36 of the driving nut 30, which allows the driving tool to be held in the relative angular position or position between the housing 38 and the driving nut 30, etc. Regardless of the relative angular position between the tool 10 and the clamping device 10, a concentric pair of successive gripping tools can be mounted behind the clamping device by pushing in a straight axial direction against the clamping device. can.

FIG. 1 shows a preferred embodiment of the invention in the clamped position, with workpieces 1 and 2 at the grasping portion 16 of the spring 12 of the device 10.
and the nose portion 40. The driving nut 30 has fully advanced within the nut holding groove 54 and is in contact with the thrust washer 64, and furthermore, the nut holding groove 5 is in contact with the thrust washer 64.
4, the actual length of each time the clamping device 10 is inserted or withdrawn. Adjusted for axial movement over its length. By determining the length of this holding @54 in this way, the driving nut can be used to help the driving tool to form a clamping force or to break.
: The rotational inertia of either the sea urchin insertion mode or the withdrawal mode can be obtained. Similarly, the length of the tool gripping surface 36 of the drive nut 30 that extends beyond the end of the housing 38 is such that the length of the tool gripping surface 36 of the drive nut 30 extends beyond the end of the housing 38 so that the drive nut 30 is in the fully advanced position within the nut retaining surface 54 (in the fully clamped mode shown in FIG. Even when the driving tool is in
It should be noted that a sufficient grasping portion 36 is left so that it can be grasped and driven.

FIG. 5 shows clamping device 10 with spring 12 in a fully extended position. That is, the ramp 14 of the spring 12 has passed completely through the nose 20 of the spreader 18 so that the spring 14 is pressed together and the gripping shoulder 16 has passed through the workpiece. When the preferred embodiment of the invention occupies this fully extended position, the drive nut 30 fully extends beyond the housing 38 and the internal threads 3 of the drive nut 30 are fully extended.
1 is completely unscrewed from the shaft A7 1-26 and the driving nut 36 is free to rotate without exerting any further axial force on the stud 24.

In the preferred embodiment shown, spring 12 and spacer 18;
Stud 24, shaft 26. All parts of the clamp pin, including the nut 30, housing 38 and washer 1748.62.64, are made of various alloy steels. These alloys were selected for their various fabrication properties and it is the object of the present invention to obtain a lamp device which is strong and able to withstand repeated clamping and loosening operations requiring high 1-L clamping forces. selected under high volume production conditions due to minimal wear and tear on the clamping equipment.

The cylindrical parts of the clamping device 10, such as the A771 threaded stud 28, the driving nut 32, and the housing 38, are all suitable for fabrication on a high-volume automatic screw machine.

However, the specific embodiments and manufacturing rates and methods described above are provided by way of example only, and those skilled in the art will be able to determine other manufacturing rates and methods for other clamping device applications without limitation. This is suggested by Similarly, it will be apparent to those skilled in the art that various modifications, adaptations, and equivalent embodiments can be made within the spirit and scope of the present invention as set forth in the appended claims.

[Brief explanation of the drawing]

1 is a side cross-sectional view of a clamping device according to the present invention provided for a pair of workpieces; FIG. 2 is a cross-sectional view taken along the line I-IT in FIG. 1; and FIG. Cross-sectional view according to ■-■, Figure 4 is the line TV in Figure 1
FIG. 5 is a partially sectional side view of the clamping device of the present invention with the pin fully extended. 1.2...Workpiece, 10...Clamp device, 12.
... Spring, 16 ... Work piece gripping surface, 18 ... Spreader, 22 ... T-shaped finger, 24 ... Stud, 26 ... Threaded shaft, 28 ... Anti-rotation characteristic, 3
0...Driver 50...Second annular groove, 52...Anti-rotation characteristic, 54...Third annular groove, 62.64...Washer, 66...Tool gripping surface

Claims (9)

[Claims] (1) An improved positive release wire spring-type clamping device for automated interim tightening and loosening of a plurality of adjacent workpieces having a plurality of aligned openings, comprising: (a) a plurality of wire-type springs; (b) a spring expander placed between the springs and separating the springs; (c) a threaded cylindrical shaft having anti-rotation characteristics along a portion of its axial length and disposed toward one end; , a cylindrical stud having a retaining device at the other end for retaining the spring; d. a cylindrical drive nut with an axially threaded through hole for engaging a thread in said shaft; a cylindrical drive nut having a raised cylindrical shoulder disposed near one end for axially retaining the nut and a tool gripping outer surface disposed near the other end; e. a first holding device for axially rotatably holding the nut; g. a cylindrical outer housing with a tool gripping outer surface; an axially through bore for receiving and retaining a spring, a spreader, a stud, a shaft, a nut, and a washer device extending outwardly at one end and with the nut extending outwardly at the other end;
The bore includes a first retaining shoulder formed at one end for axially receiving and retaining the first retaining device and the spreader.
an internal annular groove and a second annular internal groove having a retaining shoulder for axially receiving and rotatably retaining a second retaining device and a nut, the stud being capable of axial movement without rotation; an intermediate internal annular groove having anti-rotation characteristics for engaging a stud such that when the nut is rotated about an axis in one direction the spring is retracted into the housing and simultaneously expanded; When the nut rotates in the opposite direction, the spring is expanded outward from the housing and compressed together at the same time, and the tool gripping surfaces of the housing and drive nut are concentric regardless of the relative angular orientation of the housing and drive nut. A clamping device characterized by having a shape that engages and fits into a shaped driving tool. (2) The clamping device according to claim 1, wherein the tool-engaging outer surface of the housing has a substantially cylindrical shape. (3) The clamping device according to claim 1, wherein the tool gripping outer surface of the driving nut has a substantially cylindrical shape. (4) The clamping device according to claim 2, wherein the tool gripping outer surface of the driving nut has a substantially cylindrical shape. (5) The clamp device according to claim 4, wherein the diameter of the tool gripping surface of the driving nut is smaller than the diameter of the housing. (6) The clamping device according to any one of claims 1 to 5, wherein the engagement anti-rotation characteristics of the stud and the intermediate annular groove have a hexagonal cross section. (7) At least one of the retention shoulders of the first inner annular groove is roll formed into the outer housing.
Clamping device by section. (8) At least one of the retaining shoulders of the second internal annular groove is roll formed into the external housing.
Clamping device by section. (9) At least one of the retaining shoulders of the second inner annular groove is roll formed into the outer housing.
Clamping device by section.