JPH054166B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a cross-fin coil expansion machine that performs tube expansion treatment on the heat exchanger tube of a cross-fin coil and fixes the heat exchanger tube to the fin. The present invention relates to a clamp device for fixing a cross fin coil in a predetermined position of a tube expander.

[Conventional technology]

As shown in Fig. 4, the cross fin coil has a large number of fins F, F..., a large number of heat transfer tubes T in the longitudinal direction y, and 1 to 3 heat transfer tubes T in the width direction.
The structure is such that T... is inserted through a skewer, and the number of heat exchanger tubes in the y direction is usually expressed in stages, and the number of heat exchanger tubes in the z direction is usually expressed in rows. In the figure, x represents the axial direction of the heat exchanger tube T.

Conventionally, such cross-fin coils are
At the same time, the mandrels 10,
It is manufactured by inserting heat exchanger tubes T, T... and simultaneously expanding the heat transfer tubes T, T... and fixing them to the fins F, F.... There are two types of pipe expanders used for such pipe expansion, a vertical type and a horizontal type, but both types have the same basic configuration.

When expanding a cross-finned coil using a tube expansion machine, the cross-finned coil is restrained from all four circumferences by the holding frame of a clamping device at a predetermined position in the tube expansion machine so that the cross-finned coil does not move during expansion. There is a need. In addition, as a recent trend, models of cross-fin coils have become more diverse, and coils with different numbers of stages are often processed with one tube expander.

When processing cross-fin coils with different numbers of stages with one tube expander, the clamping width in the stage direction y must be changed in the clamping device according to the number of stages of the coils. Conventionally, this work has been done by reassembling the holding frame and retightening the bolts, but this has been inefficient and reduces productivity. Therefore, a clamping device that automates this reassembly work has been proposed in Japanese Patent Laid-Open No. 60-27428.

[Problem that the invention seeks to solve]

However, this clamp device uses hydraulic pressure to change the clamping width in the row direction y. When fixing the cross-fin coil using hydraulic pressure, stop the hydraulic pressure when the holding frame comes into pressure contact with the coil. Since so-called feedback control is employed, the coil is inevitably constrained more strongly than necessary, and as a result, the fins often bend at both ends in the step direction y.

In other words, when expanding a cross-fin coil, in order to prevent the coil from wobbling during expansion, it is necessary to restrain the coil from all four sides with a holding frame, but it is this holding frame that receives the force associated with expansion. Rather, it is a receiving member that supports the coil from the bottom in the heat transfer tube axial direction x. The cross-fin coil heat transfer tube shrinks in the tube axis direction due to tube expansion, so if the coil is strongly constrained from all four circumferences, the movement of the fins as the heat transfer tube shrinks will be hindered. This causes bends at the ends of the fins. This bending is noticeable at the ends in the step direction y, which are long and prone to bending.

From the above, the holding frame is ideally required to prevent only the rattling of the cross-fin coil and to avoid applying force to the coil.

Moreover, when the number of stages of heat exchanger tubes changes, the length of the cross fin coil in the heat exchanger tube axial direction x also changes accordingly. The dimensions of the holding frame are set according to the maximum length of the coil to be processed, and when processing coils shorter than this length, the dimensions of the holding frame are set so that they do not interfere with the tube expansion process. It is necessary to evacuate the necessary parts.

Furthermore, when rearranging the holding frame, it is important that the operation be quick in order to increase work efficiency.

The present invention provides a clamping device that satisfies all of these requirements.

[Means for solving problems]

FIG. 1 is a perspective view illustrating the clamping device of the present invention used in a horizontal tube expander, and the cross-fin coil 21 is set in the clamping device in a horizontal state.

To explain the features of the clamping device of the present invention with reference to FIG. 1, one of the means for clamping the cross-fin coil 21 from both sides in the row direction z is a holding plate 102, 1 divided into a plurality of parts in the heat exchanger tube axial direction x.
Consists of 02... The holding plates 102 are movable in the column direction z, and each has a dedicated drive mechanism 101.
It is equipped with

The means for clamping the cross fin coil 21 from both sides in the step direction y is provided by holding blocks 106, 106, .
It consists of 6', 106'... The holding block groups on both sides are connected in the heat exchanger tube axial direction x by connecting bodies 103 and 103', respectively, and the connecting bodies 103 and 103'
and 103' are adapted to move toward and away from each other in the step direction y by the rotation of the screw 107 in the step direction y, which is screwed into one of the screws with a normal thread and the other with a reverse thread. 108 is a rotary drive motor for the screw 107.

Note that the holding blocks 106, 106... and 1
06', 106'... may be replaced with a fixing member. Holding blocks 106', 106'...
... is replaced with a fixed member, the connecting body 1 provided on the movable side holding blocks 106, 106...
Screw the screw 107 only onto 03.

[Effect]

According to the clamping device shown in FIG. 1, only the necessary holding plates 102 are moved all at once by selectively operating the drive mechanisms 101, 101, etc. according to the length of the cross-fin coil 21 in the heat transfer tube axial direction x. While the cross-fin coil 21 is instantly restrained in the column direction z, the unnecessary holding plate remains at the original retracted position to avoid interfering with the tube expansion process.

Next, the operation of the rotary drive motor 108 causes the holding blocks 106, 106... and 106',
106' approach the cross fin coil 21 from both sides all at once and support the cross fin coil 21 in the step direction y. The rotary drive motor 108 is rotated by the holding block 106 according to the width of the coil in the step direction y by feed-forward control of the rotation angle and rotation speed.
106... can be positioned with high precision, the cross-fin coil 21 is not restrained more than necessary in the step direction y, and the fins are not bent in the subsequent tube expansion process.

Further, the operation of the rotary drive motor 108 causes the holding blocks 106, 106... and 106', 1
06'... all move at the same time, but since each holding block 106 is independently guided by the holding plate 102, at the holding plate 102 that does not require holding, the holding blocks 106, 106' Since it will remain in the retracted position like the holding plate 102, it will not interfere with the tube expansion process.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. The illustrated pipe expanding machine is a horizontal type pipe expanding machine for manufacturing cross-fin coils.

First, the overall configuration of the tube expander will be explained with reference to a plan view in FIG. 2 and a side view in FIG. One guide bar 4, 4 on each side is horizontally spanned between the fixed columns 3, 3.

The mandrel support frame 5 is movably supported in the front and back direction by guide bars 4, 4 in order to perform flare processing on the pipe end after the pipe is expanded, and horizontal screws 6, 6, one each on the left and right, are attached to the mandrel support frame 5. The block 7, which is screwed into the horizontal screw 6, is moved back and forth by being rotated by a motor (not shown) built into the block.

Between the mandrel support frame 5 and the fixed frame 2, a movable frame 8 is supported by guide bars 4, 4 so as to be movable in the front and rear direction, and the rod tip of a tube expansion cylinder 9 fixed to the rear surface of the fixed frame 2 is attached to the movable frame 8. It is pivotally mounted to drive the moving frame 8 back and forth. The horizontal screw 6 passes through the movable frame 8, and its tip is pivotally supported by the fixed frame 2 so as to be movable in the front and rear directions.

Between the mandrel support frame 5 and the moving frame 8, a plurality of intermediate plates 12 are supported by the guide rods 4, 4 so as to be movable in the front and rear direction. , 12 . . . and between the intermediate plate 12 and the movable frame 8 are connected by connecting rods 13 so as to be expandable and contractible.

In front of the mandrel support frame 5, a front frame 14 is supported by guide rods 4, 4 so as to be movable in the front and rear directions. This front frame 14 is mainly used for flaring, and is equipped with a stripper 15 and a number of flare punches corresponding to the mandrels 10 on the front side.
The entire body is moved forward and backward by a cylinder 17 fixed to the base 1. Note that the flare punch is connected and interlocked with the mandrel support frame 5.

The number of stages and rows of the mandrels 10, 10, . 5. Pass through the front frame 14 and the flare punch provided on the front frame 14, and attach the tube expansion head 18 at the tip.
(Figure 4).

A clamp device 19 is provided in front of the mandrels 10, 10 on the base 1, and the cross fin coil 21 before tube expansion is placed on the pedestal 20 so that the heat transfer tube is located on the extension line of the mandrels 10, 10... Clamp from above and from both sides. 22
is a cradle for the cross-fin coil 21, which is configured to be moved forward and backward by a screw 23.

The above is the overall configuration of the tube expander.

Next, the clamp device 19 will be explained in more detail with reference to FIG.

According to FIG. 1, a plurality of drive mechanisms 101, 101... (hydraulic cylinders) are mounted on a frame (not shown) on the pedestal 20 with the rods facing downward in the mandrel axial direction X (corresponding to the heat transfer tube axial direction x). are arranged in At the rod tip of each cylinder 101,
A holding plate 102 that controls the clamping of the cross fin coil 21 in the column direction z is fixedly provided. The holding plates 102 have an elongated planar shape, and a plurality of holding plates 102 are arranged in the mandrel axial direction X, with the longitudinal direction thereof matching the mandrel stage direction Y (corresponding to the heat exchanger tube stage direction y).

A frame (not shown) on the pedestal 20 is also provided with connecting bodies 103 and 103', one on each of the left and right sides, movable in the mandrel stage direction Y. Connector 103
and 103', rods 104, 104... and 1
04', 104', . . . are attached movably in the vertical direction, that is, in the mandrel row direction Z (corresponding to the heat exchanger tube row direction Z). Vertical rod 104, 104'
There is a stopper 1 at the top to prevent it from coming off downward.
05, and a holding block 1 at the lower end that controls the clamping of the cross fin coil 21 in the step direction y.
06,106' are fixed.

A plurality of holding blocks 106, 106' are arranged in parallel in the mandrel axial direction It is set up like this.

The screw 107, whose rotational axis is aligned with the mandrel stage direction Y, has a left-hand thread at the center of each of the connecting bodies 103, 103' for one connecting body 103, and a right-handed screw for the other connecting body 103'. Screw together with
It is designed to rotate by a rotary drive motor 108 (servo motor) fixed to the frame.

Screw 1 for connecting bodies 103, 103'
The screwing form of 07 is a reverse thread as described above, but it is also better to use a square thread for one connecting body 103 and a ball screw for the other connecting body 103'. .

If a square screw is used for one of the connecting bodies 103, 103' and a ball screw is used for the other, the screw 107
The rotational driving force of the connecting body 1 is effectively reduced, and
The screw 107 is not rotated when a force in the direction of separation is applied to the screws 03 and 103'.

If both square screws are used, the rotational driving force of the screw 107 will be large, and the load on the rotational drive motor 108 will be heavy. On the other hand, if both are ball screws, there is a risk that the screw 107 will rotate when a force in the direction of separation is applied to the connecting bodies 103, 103', making the cross-fin coil 21 unreliably restrained during pipe expansion. .

The operation of the clamping device shown in FIG. 1 will now be described.

First, before setting the cross-fin coil 21, the rotary drive motor 108 is operated to maximize the distance between the left and right holding blocks 106, 106'. Moreover, the hydraulic cylinders 101, 101...
... degenerates the rod and all retaining plates 10
2 and holding blocks 106, 106' are retracted to the upper limit position.

Next, in this state, the cross fin coil 21 before tube expansion is placed at the left-right center position on the pedestal 20 with the heat transfer tube aligned with the mandrel axis.

When the cross fin coil 21 is placed on the pedestal 20, first, the required holding plate 102 is attached depending on the length of the cross fin coil 21 in the heat exchanger tube axial direction x.
is lowered by the operation of the hydraulic cylinder 101.

Thereby, the cross fin coil 21 is fixed in the column direction z between the lowered holding plate 102 and the pedestal 20. Unnecessary holding plate 10
2 is left as is at the upper limit position.

Next, the rotary drive motor 108 is activated to rotate the screw 107. At this time, if the rotation direction of the screw 107 is set in the direction in which one of the connecting bodies 103 moves inward, the screw 107 can be rotated.
is screwed into the other connecting body 103' with a reverse thread, so the other connecting body 103' also moves inward.

In other words, the left and right connecting bodies 103, 103' simultaneously move inward due to the operation of the rotary drive motor 108, which causes the left and right holding blocks 106, 10 to move inward at the same time.
6' reduces the distance. The block interval after being reduced is set to be the same as or slightly larger than the width of the cross fin coil 21 in the step direction y, in order to avoid applying unnecessary force in the step direction y to the cross fin coil 21. do. Adjustment of the block interval by the rotary drive motor 108 is performed by the cross fin coil 21.
It is possible to control the feed according to the width of the
Allows precise spacing adjustment as described above.

Note that the operation of the rotary drive motor 108 causes the holding block 106 to move inward even in locations where the holding plate 102 is not required. However, the unnecessary holding plate 102 is left at the upper limit position, and the holding block 106 is guided by this holding plate 102, so even if it moves inward, it remains in the upper retracted position. It does not interfere with tube expansion.

The setting of the cross-fin coil 21 is completed by the above-mentioned procedure, and the pipe expansion operation continues.

To briefly explain the tube expansion operation with reference to FIGS. 2 and 3, when the setting of the cross fin coil 21 is completed with the movable frame 8 positioned at the backward limit, first, the tube expansion cylinder 9 is driven, Extend that rod.

As a result, the moving frame 8 moves forward, and the mandrel 1
0 is inserted into the heat transfer tube of the cross fin coil 21, the heat transfer tube is expanded and fixed to the fin.

At this time, the cross fin coil 21 is
The column direction z is restrained by the holding plate 102 and
The fins are restrained in the step direction y by the holding blocks 106 and 106', so that there is no wobbling as a whole, and the fins are not subjected to any force in the step direction y, so that the fins will not move as the heat exchanger tubes shrink. The fins will not be deflected or bent.

Note that the cross fin coil 21 is positioned in the row direction z by the hydraulic cylinder 101, but this does not cause the fin to bend. This is because a proximity sensor 109 is embedded in the center of the plate 102, and the hydraulic cylinder 101 is controlled by its signal to stop the hydraulic cylinder 101 as much as possible just before the holding plate 102 hits the fin.

When the tube expansion is completed, the moving frame 8 moves to the blocks 7, 7.
collides with the horizontal screws 6, 6, and
Move the mandrel support frame 5 slightly forward.

As a result, a flare punch connected to the mandrel support frame 5 is inserted into the tube end of the heat exchanger tube that has finished expanding, and flaring is performed.

When the flaring process is completed, the front frame 14 is moved forward, and the movable frame 8 is retreated while the stripper 15 provided on the front side is brought into contact with the tube plate of the cross-fin coil 21, and the mandrel 10 is extracted from the cross-fin coil 21.

When the mandrel 10 is pulled out, the front frame 14
The cross fin coil 21 is removed from the clamp device 19 in preparation for setting the next cross fin coil 21.

This removal of the cross fin coil 21 is carried out using the rotation drive motor 1 in the clamping device shown in FIG.
08 in the opposite direction, the left and right holding blocks 106,
This is done by separating the rods 106' to both sides, retracting the rod of the hydraulic cylinder 101, and raising the lowered holding plate 102 to its upper limit position.

In this embodiment, the holding blocks 106, 106'
is movable on both the left and right sides, but as mentioned above,
It is also possible to replace one of them with a fixing member.
When both the left and right sides of the holding blocks 106, 106' are movable, the movement stroke of the holding blocks 106, 106' is halved compared to when only one side is moved, and the movement stroke required to clamp the cross-fin coil 21 in the step direction y is reduced by half. Time is cut in half.

Further, in this embodiment, only one side of the cross fin coil 21 is clamped in the column direction z by the holding plate 1.
02 and the other is replaced by a fixed pedestal 20, but it is also possible to make the pedestal 20 movable up and down, or to provide a holding plate 102 in place of the pedestal 20.

Furthermore, although this embodiment is an example of a horizontal tube expander, it goes without saying that the clamp device of the present invention can be applied to a vertical tube expander.

〔Effect of the invention〕

As is clear from the above description, the clamping device of the present invention can clamp the cross-fin coil 21 in the step direction y with high precision by controlling the rotation angle or rotation speed of the motor 108, and therefore the clamping device can Cross fin coil 21
Since unnecessary force in the step direction y is not applied to the cross fin coil 21 and the cross fin coil 21 is not restrained more than necessary in the step direction y, even if the heat exchanger tube shrinks, the fins are deflected in the direction of shrinkage. There is no bending of the fins, which is highly effective in improving product quality.

Furthermore, the holding blocks 106 and 106' that control the clamping in the step direction y are connected by the connecting bodies 103 and 103', and all are driven at the same time, so that
Moreover, the drive mechanism 101 is operated simultaneously for clamping in the column direction z, and the necessary holding plates 102 are operated all at once in a short time, so the clamping can be performed in an extremely short time overall. This significantly improves work efficiency.

Further, since the holding blocks 106 and 106' are connected to each other, there is no deviation between the blocks, thereby further increasing the clamping accuracy in the step direction y.

Furthermore, by selectively operating the holding plates 102 that are divided into multiple parts in the heat transfer tube axial direction x, unnecessary holding can be avoided when the length of the cross fin coil 21 in the heat transfer tube axial direction x changes. The plate 102 can be easily retracted, and the holding block 10 can be moved in conjunction with the holding plate 102.
6 and 106' are automatically retracted, the holding plate 102 and holding block 10 are
6,106' does not get in the way.

[Brief explanation of the drawing]

Figures 1 to 3 illustrate the configuration of the pipe expander according to the present invention, with Figure 1 being a perspective view showing the clamping device of the pipe expander in detail, and Figures 2 and 3 showing the entire pipe expander. FIG. 2 is a plan view and a side view showing the structure. Moreover, FIG. 4 is a perspective view showing the cross fin coil. In the figure, 19...clamp device, 20... mount,
101... Drive mechanism (hydraulic cylinder), 102
...Holding plate, 103, 103'...Connection body,
104, 104'... Vertical rod, 105... Stripper, 106, 106'... Holding block,
107... Screw, 108... Rotation drive motor.

Claims (1)

[Claims] 1. A clamping device for a tube expander for a cross-fin coil that clamps the cross-fin coil 21 in the step direction y and the column direction z so that its heat transfer tubes are located on the axes of the mandrels 10, 10... One of the means for clamping the cross fin coil 21 from both sides in the column direction z includes holding plates 102, 102, which are divided into a plurality of parts in the heat exchanger tube axial direction x, each movable in the column direction z, and each holding plate. Drive mechanisms 101, 101 for plates 102, 102...
The means for clamping the cross-fin coil 21 from both sides in the step direction y is composed of a holding block 106, which is fixed on one side and movable in the step direction y on the holding plates 102, 102..., respectively. 106... and holding block 106,1
A connecting body 10 that connects 06... in the axial direction x of the heat transfer tube
3, a screw 107 in the step direction y that is screwed into the connecting body 103, and a rotation drive motor 108 for the screw 107. 2. In a clamping device for a tube expander for cross-fin coils, which clamps cross-fin coils 21 in the row direction y and column direction z so that the heat transfer tubes are located on the axes of the mandrels 10, 10... One of the means for clamping from both sides in the direction z includes holding plates 102, 102... which are divided into a plurality of parts in the heat exchanger tube axis direction x, each of which is movable in the step direction z, and each holding plate 102, 102... Drive mechanism 101, 101
The means for clamping the cross-fin coil 21 from both sides in the step direction y includes holding blocks 10 movable in the step direction y, respectively, on both sides of the step direction y of the holding plates 102, 102...
6,106... and 106', 106'... and
holding blocks 106, 106... and 106',
Connecting bodies 103 and 103' that connect 106'... in the heat exchanger tube axis direction A clamping device for a pipe expander, comprising a screw 107 screwed together and a rotational drive motor 108 for the screw 107.