JPH07214674A - Butt-welding apparatus of synthetic resin product - Google Patents

Abstract

PURPOSE:To accurately and efficiently perform the butt-welding of pipes or a joint and a pipe made of a synthetic resin without making difference in level in the inner diameter surfaces of them. CONSTITUTION:A fixed clamp 6 is provided to a fixed clamp stand 2 and a movable clamp 9 is provided to a movable clamp stand 3 to be allowed to advance and retreat over a definite range. After the movable clamp 9 is allowed to retreat by a specific distance, a heater stand 45 is allowed to retreat. When the light detection element 62 provided to the heater stand 45 detects the end surface position of a movable work 7, the heater stand 45 is stopped and a heater 46 is introduced into the gap between works 5,7. At that time, the axial distance (u) between the heater 46 and the light detection element is preset so that the center line (v) of the heater 46 coincides with the center position (r) of the gap between the works 5, 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for welding end faces of a synthetic resin such as polyvinyl and a joint, or end faces of a pipe member and joints, pipes and the like in a fitted state.

[0002]

2. Description of the Related Art Synthetic resin tubing such as polyvinyl tubing is widely used as ultrapure water tubing for cleaning in the manufacturing process of semiconductor devices and the like because of its extremely small amount of dissolved water components. By the way, this type of synthetic resin pipe is usually called a butt welding method in which the end portion of the pipe is heated and melted and pressure-bonded from the viewpoint that joining with an adhesive is difficult and elution of the adhesive becomes a problem. Are joined by.

An example of a conventional apparatus for performing such butt welding is disclosed in Japanese Patent Laid-Open No. 5-193004. The outline of the joining procedure in this apparatus will be described below with reference to FIG.

First, as shown in FIG. 3A, a spacer (87) is interposed between a pair of chucks (85) (86), and a pair of pipes (88) (89) are contacted with the end faces of the spacer (87). ) Is gripped by both chucks (85) (86). Next, as shown in Fig. B, the spacer (87) is retracted outward from the gap between the tubes (88) and (89), and the thin heating plate (90) is inserted into this gap. At this time, the width of the heating plate (90) is equal to that of the tubes (88) (89).
It is set so as not to contact both end faces of the. After a lapse of a predetermined time, as shown in FIG. C, the heating plate (90) is evacuated to the outside, and then one of the chucks (86) is moved forward to heat the tube melted by the heating plate (90) ( 88) (89)
The end faces of are pressed together with a predetermined pressure.

[0005]

However, in the above process, the two pipes (88) (89) fixed by the chuck are butt-welded together without checking whether or not they are correctly butt-joined. A step may occur on the inner diameter surface of the joint portion (91). That is, the tube may be deformed due to the tightening of the chuck, and if the tubes are butted and welded to each other as they are, the axial center of the joint portion is displaced and a step is formed on the inner diameter surface of the joint portion. If there is such a step, problems occur such that the flow of pure water is stagnation, impurities are easily accumulated, and it becomes a hotbed for bacteria generation. Further, since the spacer slides on the end surface of the pipe, impurities attached to the spacer are transferred to the end surface of the pipe, and as a result, impurities may be mixed in the joint portion of the pipe, resulting in a problem such as strength reduction.

In order to solve these problems, one chuck (86) is once retracted to take out the spacer (87) between the steps a and b, and then the chuck (86) is removed. It is necessary to move the tubes forward to check whether the tubes are correctly abutted with each other, and then retreat the chuck (86) by a predetermined distance, and then insert the heating plate (87), which is a complicated work. Further, in this case, an increase in the size of the device cannot be avoided.

Further, when setting the tube on the chuck, the operator must be careful to bring both end surfaces of the tube into contact with the spacers with certainty, which complicates the work. That is, if there is a slight gap between the pipes (88) (89) and the spacer (87), the heating plate (90) is inserted at the pipes (88) (8).
9) It shifts to the left and right from the center position of the gap between them, which causes uneven heating and uneven product quality.

In view of the above, according to the present invention, the butt welding of synthetic resin products can be performed accurately and efficiently so that no step is formed on the inner diameter surface of the pipes, and even if the pipes are roughly set, uneven heating does not occur. The purpose is to provide a device.

[0009]

[Means for Solving the Problems] To achieve the above object,
The device of the present invention is a device for abutting and welding the end faces of a pair of synthetic resin products,

A pair of clamps for holding both synthetic resin products with their end faces opposed to each other, a movable clamp base for sliding one clamp in a direction in which the end faces of both synthetic resin products approach and separate, and the movable clamp. A stopper that regulates the backward movement of the table and maintains the backward distance at a constant value,
A heater interposed between the end faces of both synthetic resin products to uniformly heat both end faces, a heater drive source for moving the heater between the gaps between the synthetic resin products and the outside thereof, and a movable clamp base for the heaters. A heater table that slides in parallel with the sliding direction of, and a sensor provided on the heater table so that the end surface position of the movable synthetic resin product can be detected.

The axial distance between the heater and the sensor is set so that the center line of the heater coincides with the center position of the gap between the two synthetic resin products when the end face of the movable synthetic resin product is detected by the sensor.

A pair of clamps for holding both synthetic resin products with their end faces facing each other, a movable clamp base for sliding one clamp in a direction in which the end faces of both synthetic resin products approach and separate, A stopper that regulates the retreat movement of the movable clamp base to maintain the retreat distance at a constant value, a heater that intervenes between the end faces of both synthetic resin products and heats both end faces evenly, and the heater between the synthetic resin products. The heater drive source that moves between the gap and the outside thereof, the heater base that slides the heater parallel to the sliding direction of the movable clamp base, and the end face positions of both synthetic resin products can be detected on the heater base. A sensor provided so that
After the movable side synthetic resin product retreats, find the center position of the gap between the synthetic resin products from the end face positions of both synthetic resin products detected by the sensor, and slide the heater base so that the center line of the heater matches this center position. It may be configured with a control device.

The clamp may be provided with a lock device capable of arbitrarily changing the tightening force of the synthetic resin product.

[0014]

The pair of synthetic resin products are placed on the clamp with their end faces abutting each other, and then the synthetic resin product is gripped by the clamp. If the synthetic resin products are held together by the clamps in this manner, both synthetic resin products are held concentrically thereafter. Next, the movable clamp base is retracted until it is regulated by the stopper. Then, the heater base is retracted until the sensor reaches the end surface position of the movable synthetic resin product, and when the sensor reaches the end surface position, the heater is fed into the gap between the synthetic resin products to heat both end surfaces. At this time, the axial distance between the heater and the sensor is set so that the center line of the heater coincides with the center position of the gap between the two synthetic resin products when the end face of the movable synthetic resin product is detected by the sensor. After stopping, if the heater is fed into the gap as it is, the distance from the front and back surfaces of the heater to the end surface of the synthetic resin product becomes equal and uneven heating is prevented.

Further, even if the synthetic resin product is not accurately butted and is set and clamped with a slight gap left, after the movable side synthetic resin product retreats, the sensor detects the fixed side and movable side resin products. By detecting the end face position, the width of the gap between the two synthetic resin products can be measured. Then, the center position of the gap is obtained from this measured value, and the heater base is slid so that the center line of the heater coincides with this center position, and the center line of the heater is surely aligned with the center position of the gap. You can transfer the heater with. On the other hand, it is also possible to set the amount of each gap between the movable side synthetic resin product and the fixed side synthetic resin product and the heater arbitrarily, and it is possible to freely and easily set the gap corresponding to the heating state of the synthetic resin product. Can be done.

If the clamp is provided with a lock device capable of arbitrarily changing the tightening force of the synthetic resin product, it is possible to impart an appropriate tightening force to the synthetic resin product that can prevent slipping and damage.

[0017]

Embodiments of the present invention will be described below with reference to FIGS.

As shown in FIGS. 1 to 3, a fixed clamp base (2) and a movable clamp base (3) are mounted on a base (1).
Are arranged respectively. The fixed clamp base (2) is fixed to the base (1), and a work (5) on the fixed side, for example, a fixed clamp (6) for gripping one end of a synthetic resin joint is attached to the upper surface thereof. ing. Further, on the upper surface of the movable clamp base (3), a movable work (7), for example, a pair of movable clamps (9) for gripping one end of a synthetic resin pipe is mounted separately from each other. Note that FIG.
Now, the fixed clamp (6) is shown in cross-section and the movable clamp (9) is shown in side view.

As described above, in this embodiment, the fixed clamp (6) grips the joint (5). On the contrary, the movable clamp (9) grips the joint (5) to fix the fixed clamp (5). The tube (7) may be gripped with 6). Further, both works may be pipes.

A ball nut (10) is mounted on the lower surface of the movable clamp base (3). The ball nut (10) is screwed onto a ball screw shaft (12a) which is rotatably supported on the base (1) through a support unit (11) having a plurality of bearings. Therefore, by driving the slide drive source, which will be described later, in the forward and reverse directions to rotate the ball screw shaft (12a) in the forward and reverse directions, the movable clamp base (3) can be moved forward and backward in the horizontal direction (workpiece (5 )
(7) The direction in which the end faces approach each other is called forward, and the direction in which the end faces move away from each other is called backward.

The movable clamp base (3) is provided between the fixed clamp base (2) and the movable clamp base (3) on the upper surface of the base (1).
Positioning means (13) for determining the origin position of the is provided.
The positioning means (13) expands and retracts the positioning pin (13a) by, for example, electromagnetic force, and when the positioning pin (13a) is projected, the positioning pin (13a) is extended.
The forward movement of the movable clamp base (3) is restricted by the engagement between the movable clamp base (3) and the lower part of the movable clamp base (3), while the movable clamp base (3) is free to move forward and backward when the movable clamp base (3) retreats.

On the lower surface of the movable clamp base (3), a stopper (14) for restricting the retreat operation thereof is provided. The stopper (14) is provided so as to be able to engage with the locking member (14a) fixedly provided on the upper surface of the base (1), and the stopper (14)
The last retracted position of the movable clamp base (3) is determined by the engagement between the movable clamp base (3) and the locking member (14a).
The retreat distance of is kept constant. By replacing the stopper (14) with one having a different wall thickness, the retreat distance of the movable clamp base (3) can be arbitrarily changed, and the retreat distance suitable for the work size can be obtained. In addition, in FIG. 1 to FIG.
The state where the stopper (14) and the locking member (14a) are engaged, that is, the state where the movable clamp base (3) has reached the most retracted position is illustrated.

As shown in FIG. 2, the movable clamp (9) includes a lower clamp plate (15) attached to the movable clamp base (3) and a lower clamp plate (15) via a pivot (16). It is composed of an upper clamp plate (17) attached. Upper clamp plate (17) is in closed position (shown in solid lines)
Between the open position and the open position (shown by the chain double-dashed line) about the pivot axis (16). In the open position, the restricting member (18) fixed to the lower clamp plate (15) comes into contact with the shaft, and further The opening is regulated.

At the inner diameters of the lower clamp plate (15) and the upper clamp plate (17), the lower grip portion (22) and the upper grip portion, which are semicircular arcs, are formed by the axial keys (20) (21). (23) are installed respectively. A mounting screw (24) penetrates through the upper clamp plate (17) and the key (21) with a slidable eye, and the tip end of the mounting screw (24) is screwed into the upper grip portion (23). ) Has been inserted. Therefore, when the worker turns the mounting screw (24) in a predetermined direction, the upper grip portion (23) is pulled up by the screw fitting and closely fixed to the inner diameter surface of the upper clamp plate (17).

When the mounting screw (24) is turned in the opposite direction,
The upper grip (23) falls off from the mounting screw (24). The lower grip (22) can be removed by sliding it in the axial direction. In this way, both grips (22)
Since the (23) can be attached and detached, various gripping parts (22) (2) having inner diameters corresponding to the outer diameter dimensions of the works (5) (7)
If 3) is prepared in advance, it is possible to deal with various kinds of works having different outer diameter dimensions simply by exchanging the grips (22) (23).

A retaining plate (26) is attached to the upper surface of the upper clamp plate (17). When the upper grip (23) is removed, the retaining plate (26) is attached to the mounting screw (24).
Since it engages with the large-diameter portion (25) provided in the intermediate portion, it is possible to prevent the mounting screw (24) from falling off.

The above description is for the movable clamps (9) (9).
However, the fixed clamp (6) is also constructed in the same manner.

The inner diameter surfaces of both grips (22) and (23) are
It is formed in a saw-tooth shape so as to surely prevent the gripped works (5) and (7) from coming off.

At the boundary between the lower clamp plate (15) and the upper clamp plate (17), a lock device (29) for locking both clamp plates (15) (17) is provided. The lock mechanism (29) is provided on all of the fixed clamp (6) and the movable clamps (9) (9).

The locking device (29), as shown in FIG.
A locking piece (32) rotatably attached to the upper clamp plate (17) via a shaft (31) and a pin (33) engaged with the locking piece (32) are slid in the vertical direction. And a slide mechanism (34) for. The slide mechanism (34)
The cylindrical body (35) fitted into the inner diameter of the lower end of the through hole (31) provided on the side of the lower clamp plate (15) and the vertically movable housing in the through hole (31) and the cylindrical body (35). And a support unit (37) having a plurality of bearings, and a slide member (36) having a pin (33) protruding to the side surface, and a slide member (36) inserted into the inner diameter portion of the slide member (36) by screw fitting. A vertical rotation shaft (39) rotatably supported by a lower clamp plate (15) via a tightening lever (40), and a swinging motion of the tightening lever (40) (with an axis O as a center). Is converted to a rotational force in a certain direction and transmitted to the rotating shaft (39), and when the tightening torque reaches a predetermined value, it idles to release the power transmission to the rotating shaft (39). And a wrench portion (41).

A vertical groove (not shown) communicating with the through hole (31) and accommodating the pin (33) is formed on one end surface of the lower clamp plate (15) located on the rear side of the through hole (31). Are formed. When the rotating shaft (39) is rotated in the forward and reverse directions, the slide member (36) also follows the rotation and rotates, but the slide member (36) is engaged by the side surface of the groove and the pin (33).
Since the rotation of the slide member (36) is restricted, the slide member (36) slides in the vertical direction without rotating.

Therefore, after closing the upper clamp plate (17),
A direction in which the operator operates the operation lever (42) fixed to the locking piece (32) to engage the tip of the locking piece (32) with the pin (33), and the slide member (36) descends. When the tightening lever (40) is repeatedly rocked, the pin (33) provided on the slide member (36) descends. As a result, the locking piece (32) is pulled downward, and the tightening force of the upper clamp plate (17) increases. Then, when the tightening force of the upper clamp plate (17) reaches a predetermined value, the tightening torque of the rotating shaft (39) reaches a predetermined value, and the wrench portion (41) idles to move to the rotating shaft (39). Release power transmission.

For this reason, the worker can easily grasp the work (5) (7) with a predetermined tightening force without relying on experience or intuition, and the work is deformed or damaged due to excess or insufficient tightening force. It is possible to reliably prevent disconnection. Also, by appropriately changing the set torque of the wrench part (41), an arbitrary tightening force can be obtained, so it is possible to easily obtain an appropriate tightening force that matches the material and dimensions of the work, and it can be used for many types of work. Will also be available.

A heater base (45) is arranged on the base (1). This heater base (45) is driven by a combination of a ball screw shaft (12b) and a ball nut (not shown) like the movable clamp base (3) described above, and is parallel to the sliding direction of the movable clamp base (3). Move forward and backward.

The work (5) is placed on the heater table (45).
The gap between the gaps (7) (hereinafter referred to as the heating position (A)) and the outside of this gap (hereinafter referred to as the retracted position (B)) are orthogonal to the axes of the workpieces (5) and (7). A thin plate-shaped heater (46) swinging on a flat surface is provided. As the heater (46), a heating means having any structure capable of uniformly radiating heat from the front and back surfaces can be used. In addition, the heater (4
The wall thickness (s) of 6) is compared with the distance (t) between the end faces of the workpieces (5) and (7) when the movable clamp base (3) is retracted to the last retracted position Is reduced by a predetermined amount. Therefore, the heater (46) at the heating position (A) heats the end faces of the works (5) and (7) in a non-contact state.

A heater drive source (47) including a motor is arranged on the heater table (45). Heater drive source (47)
The output shaft of the first is rotatably supported by the case (49).
The swing member (50) is connected via gears (52) (53). The first swinging member (50) is provided with a tubular portion (54) fitted into the inner diameter portion of the driven gear (53), and extends radially from the base end portion of the tubular portion (54). It is composed of a sensor support part (55) having a light receiving element (62) described later attached to the tip part. A swing shaft (56) arranged parallel to the sliding direction of the heater base (45) is concentrically held via a bearing in the inner diameter portion of the tubular portion (54). ) Fixed clamp (6) side end, heater (46) at one end
Is attached to the other end of the second swinging member (57). The first swinging member (50) and the second swinging member (57) are suitable connecting means (not shown) so that they can swing together.
Are connected using. As a result, the heater drive source (47)
When it is rotated forward and backward, the light receiving element (62) and heater (46)
Will swing integrally around the swing shaft (56) (see FIG. 2).

A sensor (60) for detecting the position of the end surface of the movable work (7) is provided on the side of the clamps (6) (9).
Are placed. As the sensor (60), a transmissive sensor, for example, an optical sensor including a light emitting element (61) and a light receiving element (62) can be used. In the present embodiment, the case where the light emitting element (61) and the light receiving element (62) are arranged opposite to each other with the movable clamp (9) interposed therebetween and the light receiving element (62) is swingable is illustrated.

Specifically, the light emitting element (61) is mounted obliquely upward on the sensor support base (63) arranged on the side of the base (1), while the light receiving element (62) is As described above, the light receiving surface is attached to the sensor support portion (55) of the first swing member (50) with the light receiving surface facing the clamps (6) (9). The sensor support base (63) is connected to the heater base (45) via a connection member (not shown) so that the sensor support base (63) can move integrally with the heater base (45). In FIG. 4, the light receiving element (62) is omitted.

A detection means (not shown) such as a limit switch is provided in the swing region of the first swing member (50) or the second swing member (57). This detection means contacts, for example, the first swing member (50) immediately before the axes of the light emitting element (61) and the light receiving element (62) coincide with each other, and transmits a detection signal to a control device (not shown). The control device stops the heater drive source (47) based on this detection signal, and as shown in FIG. 2, the light emitting element (61) and the light receiving element (62) are integrated with each other with their axes aligned. The amount of light received by the light receiving element (62) is sequentially managed by sliding (hereinafter, the stop position of the heater (46) at this time is referred to as an intermediate position (C)).

FIG. 4 shows a drive system for the movable clamp base (3) and the heater base (45). As shown in the figure, the movable clamp base (3) and the heater base (45) are driven by a single slide drive source (67) composed of a servomotor or the like via two power transmission paths (66a) (66b). To be done. The output shaft of the slide drive source (67) has three gears (68) (69
a) A powder clutch (70a) provided on both power transmission paths (66a) and (66b) after being bifurcated by (69b)
(70b), shaft coupling (71a) (71b), reduction gear (72a)
(72b), a pair of pulleys (73a) (73b) and belts (74a) (74b), respectively, below the movable clamp base (3) and the heater base (45), the ball screw shaft (12a) ( 12b).

The device of the present invention has the above configuration. Hereinafter, a welding work procedure by the apparatus of the present invention will be described with reference to FIGS. 6 to 10.

First, as shown in FIG. 6, the positioning pin (13a) of the positioning means (13) is projected so that the movable clamp base (3) is located at the origin position. Next, the work (5) (7) is attached to the fixed clamp (6) and the movable clamp (9).
The end surfaces of the workpieces are abutted against each other, and the above-mentioned lock device (29) is operated to securely fix the works (5) and (7). At this time, the position of the abutting portion (75) of both works (5) and (7) can be arbitrarily set between the end surface of the fixed clamp (6) and the end surface of the movable clamp (9) facing the end surface. .

Next, the powder clutch (70b) on the heater base (45) side is freed, and the magnetic field is applied to the powder clutch (70a) on the movable clamp base (3) side to apply frictional force between the clutch elements. Let In this state, the slide drive source (67) is activated, the ball screw shaft (12a) on the movable clamp base (3) side is rotated, and the movable clamp base (3) is retracted. When the movable clamp base (3) retracts by a predetermined distance, the stopper (14) and the locking member (14a) engage with each other, and the retracting operation of the movable clamp base (3) is restricted. As a result, as shown in FIG. 7, a gap (76) having a width equal to the retracted distance of the movable clamp base (3) is formed between the end faces of the works (5) and (7). After this, positioning means (13)
Is activated to retract the positioning pin (13a) below the lower surface of the movable clamp base (3).

Next, the heater driving source (47) is driven to position the heater (46) at the intermediate position (C), and the light emitting element (6)
Align the axes of 1) and the light receiving element (62). Subsequently, the powder clutch (70a) on the movable clamp (9) side is demagnetized to be free, and a magnetic field is applied to the powder clutch (70b) on the heater base (45) side to retract the heater base (45). As shown in FIG. 8, when the light emitting element (61) and the light receiving element (62) reach the vicinity of the end face of the movable work (7),
Part of the light transmitted from the light emitting element (61) is blocked by the end surface of the work, and the amount of light received by the light receiving element (62) is reduced. When the amount of light received by the light receiving element (62) becomes less than a predetermined threshold value, the control device that recognizes this detects that the slide drive source (67)
To stop the heater base (45). After that, the heater drive source (47) is activated, and as shown in FIG. 9, the heater (46) at the intermediate position (C) is transferred to the heating position (A) to perform the heating work.

By the way, during such heating, the end faces of the works (5) and (7) must be heated uniformly.
Therefore, in the present invention, the heater (46) and the light receiving element (62)
The axial distance (u) between them (the horizontal distance between the center line v of the heater in the width direction and the axis w of the light receiving element: see FIG. 3) is
It is set to a predetermined distance in consideration of the stop position of the heater base (45). Specifically, when the heater base (45) is stopped, the center line (v) of the heater (46) is aligned with the work (5) (7).
It is set to match the center position (r) of the gap (76) between them. As a result, the distances from the front and back surfaces of the heater (46) to the end faces of the works (5) and (7) are equalized, so that the end faces of the works (5) and (7) can be heated uniformly. Then, after stopping the heater table (45), if the heater (46) is transferred to the heating position (A) as it is, the heater (46) is automatically moved to the work (5) without correcting the position of the heater (46). It can be arranged at the center of the gap (76) between (7).

The same effect can be obtained by adjusting the threshold value of the amount of received light and shifting the stop position of the heater base (45) forward and backward.

After a lapse of a predetermined heating time, as shown in FIG. 10, the heater driving source (47) is reversely activated to turn on the heater (46).
To the retracted position (B). Then, the slide drive source (67) is reversely activated, the movable clamp base (3) is moved forward, and the end faces of the works (5) and (7) are butted against each other. After the butting, since the powder clutch (70a) on the movable clamp (9) side transmits a constant torque while slipping between the clutch elements, the ball screw shaft (12a) transmits to both end surfaces of the work (5) (7). Is applied with a constant crimping force.
This crimping force can be adjusted by appropriately changing the set torque of the powder clutches (70a) and (70b).
The value can be changed to a value suitable for the dimension and material of (7).

After the welding of the works (5) and (7) is completed, the fixed clamp (6) and the movable clamp (9) are opened to take out the joined works (5) and (7), and the positioning means (13) is activated. So that the positioning pin (13a) is projected.
After that, the slide drive source (67) is activated to return the movable clamp base (3) to its original position, and the same work is performed thereafter.

From the above structure, the device of the present invention has the following effects.

In the device of the present invention, the workpieces (5) and (7) are temporarily abutted before clamping, and after confirming that the two are accurately abutted, the workpieces (5) and (7) are clamped and welded. A step is unlikely to occur. Therefore,
Even if the product is used for piping, it does not become a hotbed for the generation of stagnation and bacteria, and is suitable as a pipe for ultrapure water piping.

The spacer (8
7) is not required, and the structure can be simplified. Also, unlike the conventional device, the spacer (87) does not slide on the end surface of the work, and therefore impurities do not transfer from the spacer to the end surface of the work, preventing problems such as strength reduction due to mixing of impurities. It is possible to obtain high quality products.

The matching of the works (5) and (7) is
It can be carried out at any position between the end surface of the fixed clamp (6) and the end surface of the movable clamp (9) opposed thereto.
Therefore, the workability is improved as compared with the conventional device in which the end surface of the tube must be accurately brought into close contact with the spacer.

For the purpose of surely eliminating the step portion generated on the inner diameter surface of the joint portion, as shown in FIG. 11, the work (5) (7)
Align the axes with a sterilized jig (78) between them,
In this state, the works (5) and (7) may be clamped, and then the jig (78) may be pulled out to weld the end faces to each other. When the jig (78) is used in the device of the present invention, the workpieces (5) and (7) are held by the clamps (6) and (9) with the jig (78) interposed as shown in FIG. The jig (78) may be removed at the stage shown in. In this case, if the axial distance (u) is set in consideration of the width (p) of the outer diameter end of the jig (78), both end surfaces of the work can be heated uniformly. On the other hand, in the conventional device, since the spacer (87) is interposed between the works when clamping the works, it is difficult to arrange the jig (78), and even if the jig is arranged, the effect is not sufficient. It has the drawback that it cannot be obtained.

In the above description, an optical sensor is used as the sensor (60), but the same effect can be obtained by using a touch sensor. Specifically, the touch sensor is attached to the sensor support portion (55) in FIG. However, in this case, the swing area of the touch sensor is clamped more than the swing area of the light receiving element (62) so that the detection portion of the touch sensor can come into contact with the end surface of the movable work (7) during detection. It is necessary to set it on the (9) side. In addition, when the heater (46) is shaken after the end surface position of the movable work (7) is detected, a touch sensor is installed between the works (5) and (7) to prevent collision and interference with the heater (46). It is necessary to evacuate outside the gap. Therefore, it is desirable that the heater (46) and the touch sensor are independently driven by different driving sources and rocked.

Another embodiment of the present invention will be described below. This is because, in the apparatus shown in FIGS. 1 to 4, after the movable side work (7) is retracted, the sensor (60) directly measures the end face positions of both works (5) and (7), and from this measurement value The center position (r) of the gap between the works (5) and (7) is obtained, and the heater (46) is fed into this center position (r).

A specific work procedure in this case will be described.
First, as shown in FIGS. 6 and 7, the fixed works (5) and (7) are held by the fixed clamp (6) and the movable clamp (9) at the origin position, respectively, and the slide drive source (67) is activated. Then, the movable work (7) is retracted. Then, after the movable clamp base (3) is stopped by the engagement of the stopper (14) and the locking member (14a), the heater drive source (47) is activated, and as shown in FIG. )
The sensor (60) is arranged between the end faces of (7). As the sensor (60) in this case, both an optical sensor and a touch sensor can be used. Next, the heater base (45) is moved forward and backward, and the sensor (60) detects the end face positions of the fixed-side and movable-side works (5) and (7). Based on this, the controller (80) connected to the sensor (60) calculates the center position (r) of the gap between the works (5) and (7), and the center line (v) of the heater (46) is calculated. The slide drive source (47) is driven so as to match the center position (r). After that, the heater driving source (47) is activated, and the heater (46) is transferred to the heating position (A) to perform the heating work.

According to this apparatus, the center position (r) of the gap between the works (5) and (7) is directly obtained, and the heater (46) is fed into this center position (r).
In addition to the effect of, the unique effect that the work (5) (7) can be roughly set is achieved. That is, as shown in FIG. 13, even when the workpieces (5) and (7) are not accurately butted and clamped with a slight gap (81), the center line ( v) can be matched to the center position (r) of the gap.

[0058]

With the above construction, the apparatus of the present invention surely prevents the uneven heating of the work, and exhibits the following respective effects.

In the device of the present invention, the synthetic resin products are temporarily butted before being clamped, and after confirming that the two are correctly butted, they are clamped and welded, so that a step is generated on the inner diameter surface of the joint after welding. It gets harder. Therefore, even if the product is used for piping, it does not become a hotbed for generation of stagnation and bacteria, and it is suitable as a piping pipe for ultrapure water.

The spacer, which is indispensable in the conventional device, is unnecessary, and the structure can be simplified. In addition, unlike the conventional device, the spacer does not slide on the end surface of the synthetic resin product, and therefore the impurities do not transfer from the spacer to the end surface of the synthetic resin product. It is possible to prevent it and to obtain a high quality product.

The butt position of the synthetic resin product is arbitrary as long as it is between the end faces of the fixed clamp and the movable clamp. Therefore, the workability is improved as compared with the conventional device in which the end surface of the tube must be accurately brought into close contact with the spacer.

Further, after the movable side synthetic resin product is retracted, the center position of the gap between the synthetic resin products is obtained from the end face positions of both synthetic resin products detected by the sensor, and the center line of the heater is aligned with this center position. By providing the control device that slides the heater base, in addition to the above-mentioned effects, the unique effect that the synthetic resin product can be set in the clamp more roughly than the conventional device is achieved. That is, even if the synthetic resin products are not accurately butted and are clamped with a slight gap, the center line of the heater can be surely aligned with the center position of the gap.

Further, if the clamp is provided with a lock device capable of arbitrarily changing the tightening force of the synthetic resin product, it is possible to impart an appropriate tightening force capable of preventing the synthetic resin product from coming off or being damaged. It can also be used for various types of synthetic resin products with different dimensions.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a device of the present invention.

FIG. 2 is a front view of the device of the present invention.

FIG. 3 is a plan partial cross-sectional view of the device of the present invention.

FIG. 4 is a horizontal sectional view taken along the line DD in FIG.

FIG. 5 is an enlarged cross-sectional view of a lock device.

FIG. 6 is a plan view showing a welding work procedure by the device of the present invention.

FIG. 7 is a plan view showing a welding work procedure of the device of the present invention.

FIG. 8 is a plan view showing a welding work procedure of the device of the present invention.

FIG. 9 is a plan view showing a welding work procedure of the device of the present invention.

FIG. 10 is a plan view showing a welding operation procedure of the device of the present invention.

FIG. 11 is a partial cross-sectional plan view when a jig is interposed between works.

FIG. 12 is a plan view showing another embodiment of the device of the present invention.

FIG. 13 is a plan view showing an application example of the device of the present invention.

FIG. 14 is a plan view showing a welding procedure of a conventional device.

[Explanation of symbols]

 3 Movable clamp base 5 Synthetic resin product (fixed work) 6 Clamp (fixed clamp) 7 Synthetic resin product (movable work) 9 Clamp (movable clamp) 14 Stopper 29 Lock device 45 Heater base 46 Heater 47 Heater drive source 60 Sensor 80 Control unit u Distance between axes

Claims (3)

[Claims] 1. A device for abutting and welding end faces of a pair of synthetic resin products, the pair of clamps holding both synthetic resin products with their end faces facing each other, and a pair of clamps for both synthetic resin products. Between the end faces of both synthetic resin products, a movable clamp base that slides one clamp in the direction in which the end faces approach and separate, a stopper that regulates the retreat movement of the movable clamp base and maintains the retreat distance at a constant value. A heater intervenes to uniformly heat both end surfaces, a heater drive source for moving the heater between the gaps between the synthetic resin products and the outside thereof, and the heater is slid in parallel with the sliding direction of the movable clamp base. A heater base and a sensor provided on the heater base so that the end surface position of the synthetic resin product on the movable side can be detected, and the axial distance between the heater and the sensor is Butt welding apparatus of a synthetic resin product characterized in that it is set to the center line of the heater matches the center position of the gap between the two plastic product when the end face detection of the movable plastic products by. 2. A device for abutting and welding the end faces of a pair of synthetic resin products together, the pair of clamps holding both synthetic resin products with their end faces facing each other, and a pair of clamps for both synthetic resin products. Between the end faces of both synthetic resin products, a movable clamp base that slides one clamp in the direction in which the end faces approach and separate, a stopper that regulates the retreat movement of the movable clamp base and maintains the retreat distance at a constant value. A heater intervenes to uniformly heat both end surfaces, a heater drive source for moving the heater between the gaps between the synthetic resin products and the outside thereof, and the heater is slid in parallel with the sliding direction of the movable clamp base. The heater table, a sensor provided on the heater table so that the end surface positions of both synthetic resin products can be detected, and the movable side synthetic resin product is retracted and then detected by the sensor. Obtains the center position of the gap between the synthetic resin product from the end face position of the synthetic resin products,
A butt welding device for synthetic resin products, comprising: a control device that slides the heater base so that the center line of the heater coincides with the center position. 3. The butt welding apparatus for synthetic resin products according to claim 1, wherein the clamp is provided with a lock device that can arbitrarily change the tightening force of the synthetic resin product.