JPH0211337B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention mainly relates to the installation of a mandrel in a tube expansion device used for expanding a tube by press-fitting the mandrel into a tube for a heat exchanger or the like. This invention relates to a mandrel mounting device that can be used reliably.

(Prior Art) In general, the arrangement of a mandrel attached to this type of tube expansion device must be changed sequentially depending on the arrangement of the tubes to be expanded.

Therefore, conventionally, various means have been developed for easily attaching and detaching the mandrels when changing the arrangement of the mandrels. As an example,
The applicant has previously developed a mandrel mounting device according to Utility Application No. 172752/1983.

As shown in FIG. 7, this device includes a holder 8 for hanging the upper part of the tube expansion mandrel 1 on the upper surface side of a mounting plate 4 provided at the lower part of the pushing body 5 which can be raised and lowered by a cylinder or the like. The mandrel 1 held and attached to the holder 8 can be pressed during pipe expansion work by an attachment 18 fixedly inserted into the hollow part 21a above the mounting plate 4 and the holder 8. be. Here, the mechanism connects the upper part of the mandrel 1 to the hole 1 of the holder 8.
The stepped portion 3 of the mandrel 1 and the holder 8 are inserted into the mandrel 1 and rotated relative to the holder 8.
The engaging portion 14 is configured to be freely engageable and detachable. In addition, on the lower surface of the attachment 18,
A rotation-stopping engagement portion 19 for engaging the upper portion (recessed portion 17a) of the holder 8 is provided. In such a configuration, by engaging the upper part of the holder 8 with the engaging part 19 of the attachment 18 and rotating the mandrel 1, the mandrel 1 is attached to the holder 8.
This allows the mandrel 1 and the holder 8 to be reliably engaged and disengaged.

(Problem to be Solved by the Invention) However, in the conventional means, the attachment 18 is disposed in a fixed state in the predetermined hollow part 21a, and the rotation-stopping engagement part 19 is attached to the holder 8.
Because it is always located above the , the following practical problems have arisen.

That is, during tube expansion work with the mandrel 1 attached, the tip of the mandrel 1 contacts or press-fits into the tube 31 and the mandrel 1 and holder 8 rise, so the upper part of the holder 8 is connected to the engagement part of the attachment 18. 19 and is stopped from rotating. Therefore, if a rotational force is generated due to a torsional force acting on the mandrel 1 in this state, the engagement between the mandrel 1 and the holder 8 is released, and the mandrel 1 is detached from the mounting plate 4. do.

However, since the support of the mandrel 1 is incomplete in this case, it is not possible to carry out proper pipe expansion work, and the work safety is also poor, and even if the pushing body 5 is subsequently raised, the mandrel 1 cannot be removed from the pipe 31. There were also situations where it was not possible to do so, resulting in very poor workability.

Therefore, the present invention eliminates the risk of the mandrel being inadvertently detached from the holder even if rotational force is generated on the mandrel attached to the holder, thereby ensuring that the mandrel is securely attached. The purpose of this is to ensure that the pipes are maintained and that there is no hindrance to the pipe expansion work.

(Means for Solving the Problems) The present invention solves the above problems by devising the mounting state of the attachment so that even if the upper part of the holder comes into contact with the mandrel pressing attachment during pipe expansion, the holder does not stop rotating. The aim is to solve this problem.

That is, the present invention has a stepped portion 3 formed on the upper surface side of the mounting plate 4 provided at the lower part of the pushing body 5 which can be raised and lowered by relative rotation with the mandrel 1 for expanding the pipe. Engagement part 14 that can be engaged and detached freely
A holder 8 for retaining the mandrel is provided, and a hollow part 21 provided above the holder 8 and the mounting plate 4 is provided with a hollow part 21 which is provided with a holder 8 which contacts the holder 8 when the pushing body 5 is lowered and holds the mandrel. An attachment 18 for pressing the holder 8 is disposed on the lower surface of the attachment 18 to prevent the holder 8 from rotating.
In a mandrel mounting device for a tube expansion device, a concave or convex holder rotation stop engaging portion 19 that can be engaged with the upper part of the holder 8 is formed in accordance with the arrangement position of the holder 8. , empty
The holder rotation stopping engaging part 19 is formed to have a width narrower than the width of the hollow part 21 so that it can slide in the horizontal direction within the part 21 and be retracted from a position directly above the holder 8. This is a mandrel mounting device in a tube expansion device.

(Function) In the above configuration, when the rotation-stopping engaging portion 19 of the attachment 18 is disposed above the holder 8, the rotation of the holder 8 is prevented by engaging the two. The mandrel 1 can be rotated relative to the mandrel 1, and the engagement and disengagement between the stepped portion 3 of the holder 8 and the engaging portion 14 of the mandrel 1 can be performed freely.

If the attachment 18 is moved in the width direction of the mounting plate 4 and the engaging portion 19 of the attachment 18 is retracted from the position above the holder 8,
The engagement between the engaging portion 19 and the holder 8 is reliably prevented. Therefore, even if a rotational force is generated on the mandrel 1 during pipe expansion work when the mandrel 1 of the holder 8 is hooked, the holder 8 will rotate following the mandrel 1, and the stepped portion 3 of the holder 8 will rotate.
There is no possibility that the engagement between the mandrel 1 and the engagement portion 14 of the mandrel 1 will be released. Therefore, the mandrel 1 will not be accidentally separated from the holder 8.

(Example) Examples of the present invention will be described below.

In Figures 1 and 2, reference numeral 1 denotes an elongated rod-shaped tube expansion mandrel that is press-fitted into the tube to be expanded, and an eccentric small-diameter portion 2 is formed at the top of the mandrel, and a concave stepped portion 3 is formed on the side surface of the mandrel. It is set in. Reference numeral 4 denotes a mounting plate that is attached to the lower part of the vertically movable pushing body 5 via support plates 30, 30, and the lower plate has small-diameter insertion holes 6 for inserting the mandrel 1 in, for example, four rows in a staggered manner. A large number of recesses 7 are formed in the shape of a shape, and a large diameter recess 7 is provided on the upper surface side and is connected to each insertion hole 6 .

Reference numeral 8 indicates a holder for holding a mandrel housed in each recess 7 of the mounting plate 4. As shown in FIG. 3, the holder 8 is made up of two holder bodies 9, 9a each having a halved cylindrical member, facing each other and having a fitting portion 10 formed therein. 11
is a ring-shaped coil spring fitted into the holder bodies 9, 9a, which elastically biases the two holder bodies 9, 9a in a direction to maintain their facing state, as shown in the figure. As shown in A and B, the entire structure can be expanded and contracted. Reference numerals 12 and 12 indicate guide shafts that are fitted into holes 13 made in each holder body 9 and 9a when the holder 8 expands and contracts; 14 indicates a guide shaft that is approximately arcuate in planar shape on the curved inner surface 15 of one holder body 9; This is an engaging portion that protrudes from.

In FIGS. 1 and 2, reference numeral 18 denotes an attachment interposed in the hollow part 21 between the upper surface of the mounting plate 4 and the lower surface of the pushing body 5, and its width is the same as that of the hollow part 21.
The mounting plate 4 is formed to be narrower by a dimension L than the mounting plate 4, and is configured to be slidable within the hollow portion 21 along the width direction of the mounting plate 4 (in the direction of arrow A). In addition, the above dimension L
is approximately 1/2 of the drilling pitch l of the insertion hole 6 of the mounting plate 4
is set to . Reference numeral 19 denotes grooves (corresponding to rotation-stopping engagement parts) carved in the lower surface of the attachment 18, and are provided in a total of four parallel grooves corresponding to the arrangement pitch of the insertion holes 6 of the mounting plate 4. Reference numeral 20 indicates a large number of holes drilled along the groove 19 in the same arrangement as the insertion holes 6 of the mounting plate 4.

Reference numeral 22 denotes a lever for operating the attachment slide connected to one side of the attachment 18, and is provided so as to penetrate one of the support plates 30 that supports the mounting plate 4 and protrude to the outside. 23,2
Reference numeral 3a denotes a positioning body having a ball 24 biased by a spring or the like projected from the tip thereof, which is screwed onto a support 25 that supports the side of the mounting plate 4, so that the ball 24 is attached to the attachment 18. It can be freely engaged with and disengaged from the V-shaped grooves 26, 26a carved on the sides.

The present embodiment has the above configuration, and its usage and operation will be explained next.

First, in order to attach the mandrel 1 to the mounting plate 4, insert the concave groove 19 of the attachment 18 into the holder 8.
With the upper part of the mandrel 1 aligned with the upper position, the upper part of the mandrel 1 is inserted into the insertion hole 6 of the mounting plate 4 from the lower side and press-fitted into the fitting part 10 of the holder 8, as shown in FIG. Next, the mandrel 1 is raised and the convex portion 17 at the upper end of the holder 8 is raised as shown in FIG.
is engaged with the groove 19 of the attachment 18 to stop the mandrel 8 from rotating. If the mandrel 1 is rotated in this state, the stepped portion 3 of the mandrel 1
can be engaged with the engaging portion 14 of the holder 8. Thereby, the mandrel 1 can be hung on the mounting plate 4 and the holder 8 as shown in FIGS. 1 and 2.

Next, when the pushing body 5 is lowered to expand the tube placed below the mandrel 1 after the attachment of the mandrel 1 is finished, the attachment 18 is
As shown in the figure, the hollow part 21 is moved to the left in the drawing, and the groove 19 is arranged at the center position between each holder 8, 8.

If the tube expansion operation is performed in this state, the upper part of the holder 8 will come into firm contact with the attachment 18 due to the reaction of the mandrel 1, which is lowered as the pushing body 5 is lowered, during tube expansion.
The upper part of the attachment 18 only comes into contact with the planar lower surface of the attachment 18 and does not engage with the groove 19. Therefore, even if a rotational force is generated by applying a twisting force to the mandrel 1 at that time, the holder 8 rotates together with the mandrel 1. Here, since the disengagement between the two is performed only by relative rotation thereof, the engaged state between the holder 8 and the mandrel 1 is never disengaged. Therefore, the attachment of the mandrel 1 is held securely, and proper pipe expansion work can be performed.

In addition, at this time, the V-shaped groove 2 of the attachment 18
If the ball 24 of the positioning body 23 is set to be engaged with the mandrel 1, the attachment 18 will not move inadvertently to the right, and the mandrel 1 will be prevented from slipping out more reliably.

Furthermore, when replacing parts or changing the arrangement of mandrel 1 after pipe expansion work, use attachment 18.
After returning to the original position shown in FIG. All you have to do is cancel the connection. After disengaging, pull the mandrel 1 downward and release the holder 8.
can be easily extracted from. Also, to confirm that the mandrel 1 and the holder 8 are disengaged, raise the mandrel 1 slightly and remove the attachment 18.
This can be easily confirmed by pushing it up into the hole 20.

In the above embodiment, the groove 19 was carved on the lower surface of the attachment 18 or the protrusion 17 was provided on the upper part of the holder 8 to enable engagement between the two, but the present invention is not limited to this. For example, as shown in FIG. 7 as a conventional example, a groove may be formed in the upper part of the holder 8, and a protrusion that engages with the groove may be provided on the lower surface of the attachment 18. In short,
An engaging portion 19 that can be engaged with the upper portion of the holder 8 may be provided on the lower surface of the attachment 18 so that the rotation of the holder 8 can be stopped.

Further, in the above embodiment, the attachment 18 is made movable by a dimension of 1/2 of the arrangement pitch l of the plurality of holders 8, but the amount of movement of the attachment 18 is not limited to this. Further, the means for moving the attachment 18 is not limited to the means for manually operating the lever 22 as described above. It may be moved using an air cylinder or the like.

In addition, the present invention includes mandrel 1 and mandrel 1.
The specific structure of each part such as the holder 8 for hanging can be freely changed within the scope of the present invention.

(Effects of the Invention) As described above, the present invention provides an engagement for rotating the holder in the hollow portion provided above the holder for hanging the mandrel, which allows the mandrel to be attached and detached by relative rotation with the mandrel. The attachment is provided so that it can slide freely along the width direction of the mounting plate, and the engaging part of the attachment can be retracted from the upper position of the holder. By retracting the holder, the holder is prevented from engaging with the attachment, and even if rotational force is generated on the mandrel during work on the expanded pipe, the mandrel can be moved independently against the holder that is stopped from rotating as in the past. This eliminates the possibility of rotation and makes it possible to reliably prevent the mandrel from being accidentally removed from the holder.

As a result, the present invention has the special effect of being able to eliminate the need for pipe expansion work caused by improper detachment of the mandrel, and to perform the pipe expansion work with excellent safety.

In addition, the present invention makes it possible to easily attach and detach the mandrel to and from the holder after the holder is in a rotation-stopped state by simply moving the attachment and placing its rotation-stopping engagement portion above the holder. Switching between preventing the mandrel from coming off and attaching and detaching it can be done in a so-called one-touch operation, which has the advantage of further improving the efficiency of the pipe expansion process. .

[Brief explanation of drawings]

1 to 3 show an embodiment of the device according to the present invention, in which FIG. 1A is a cross-sectional plan view of the main part, FIG. An enlarged cross-sectional view of the main part, and Figures 3A and 3B are plan views of the holder. Figures 4 to 6 show the state of use, Figure 4 is a cross-sectional view of the main part before mounting the mandrel, Figure 5 is a cross-sectional view of the main part during the mandrel mounting work, and Figure 6 is when preventing the mandrel from falling off. A sectional view of the main parts. FIG. 7 is a sectional view of main parts showing a conventional example. 1... Mandrel, 3... Step part, 4... Mounting plate, 5... Pushing body, 6... Insertion hole, 8... Holder, 18... Attachment, 19... Engaging part (concave groove) , 21... empty section.

Claims (1)

[Claims] 1 The upper surface side of the mounting plate 4 provided at the lower part of the pushing body 5 which can be raised and lowered is removably engaged with the stepped portion 3 formed at the upper part of the mandrel 1 by relative rotation with the mandrel 1 for tube expansion. A holder 8 for hooking and holding the mandrel, which is provided with a joint 14, is provided, and a gap 21 provided above the holder 8 and the mounting plate 4 is provided with a holder 8 that comes into contact with the holder 8 when the pushing body 5 is lowered. An attachment 18 for pressing the mandrel 1 is disposed, and the bottom surface of the attachment 18 has a concave or convex shape that can be engaged with the top of the holder 8 to stop the rotation of the holder 8. In a mandrel mounting device for a tube expansion device in which a holder rotation stop engaging portion 19 is formed corresponding to the arrangement position of the holder 8, the attachment 18 slides horizontally within the hollow portion 21. The engaging part 19 for stopping rotation of the holder
A mandrel mounting device for a tube expansion device, characterized in that the mandrel is formed to have a width narrower than the width of the hollow portion 21 so that it can be retracted from a position directly above the holder 8.