JP2015081553A - Liquid pressure type pipe expansion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid pressure type pipe expansion device that enables pressurization control to make liquid into a desired pressure with accuracy and reproducibility, and also facilitates maintenance of the device.SOLUTION: A liquid pressure type pipe expansion device 1 includes: a liquid supply tank 6 that stores pipe expansion liquid W1; a pressure increasing machine 4 that increases the pressure of pipe expansion liquid W1 from the liquid supply tank 6 to make it into ultrahigh pressure; and a pipe expansion tool part 3 that injects pipe expansion liquid W2 of ultrahigh pressure from the pressure increasing machine 4 to a seal part performing pipe expansion molding. The pressure increasing machine 4 includes an electric motor 48, a motion conversion mechanism 49 converting rotational motion of the electric motor 48 into a reciprocating motion of a plunger 45, and a pressure holding valve 42.

Description

  The present invention relates to a hydraulic pipe expanding apparatus.

  2. Description of the Related Art A hydraulic tube expansion device is known as a device that joins a tube and a tube plate of a heat exchanger such as a boiler or a condenser. The hydraulic-type tube expanding device is a device that expands the tube by supplying a liquid whose pressure has been increased to several thousand atmospheres to an aqua tube and causing it to act directly from the inner surface of the tube. By using a hydraulic type pipe expanding device, the tube and the tube plate can be fixed accurately and firmly. Further, unlike the method of rolling and plastically deforming the inner surface of the tube, there are advantages such as not damaging the inner surface of the tube and being easy to cope even if the tube expansion range is long. For this reason, the demand of a hydraulic-type pipe expansion apparatus is increasing.

  Patent Document 1 relates to a hydraulic-type tube expansion device, and relates to a tube-expansion tool portion that is equipped with a seal portion that performs tube-expansion molding by the liquid pressure of an ultra-high pressure liquid, and injects the ultra-high-pressure liquid into the seal portion, and this tube expansion tool portion And a main body for supplying the ultrahigh pressure liquid to the tube expansion tool section, and the main body and the tube expansion tool section are configured separately. It is a hydraulic type pipe expansion molding device, wherein the main body has a liquid supply tank for storing a pipe expansion liquid used for pipe expansion molding, and a liquid supply unit having a liquid supply pump for pumping the stored pipe expansion liquid to the pipe expansion tool part. And a pressure intensifier provided between the liquid supply pump and the tube expansion tool part, further increasing the pressure of the pipe expansion liquid pumped from the liquid supply pump and supplying the ultrahigh pressure liquid to the tube expansion tool part, Liquid pump and pressure booster A hydraulic unit having a hydraulic pump for supplying pressure oil; and when the valve is closed, the pressure of the ultrahigh pressure liquid discharged from the pressure intensifier is maintained and supplied to the seal portion, and when the valve is opened, the ultrahigh pressure liquid is supplied And a pressure holding valve for discharging to the drain.

  Patent Document 2 relates to a hydraulic-type tube expansion device, and relates to a tube-expanding tool unit that is equipped with a seal portion that performs tube-expansion molding using the liquid pressure of an ultra-high-pressure liquid, and injects the ultra-high-pressure liquid into the seal portion. A main body that supplies the ultra-high pressure liquid to the main body, and the main body and the tube expansion tool portion are configured as separate bodies, and the tube expansion tool portion is held in the hand by a worker to perform tube expansion work. An apparatus, wherein a booster for expanding and forming a tube-expanded liquid to be expanded into the main body by the hydraulic pressure is discharged from a discharge hole, a liquid supply unit for supplying the tube-expanded liquid to the booster, and the hydraulic pressure to the booster A hydraulic unit that supplies pressure oil that generates pressure, and the hydraulic pressure of the ultra-high pressure liquid is a hydraulic pressure of ultra-high pressure water, and the tube expansion tool portion communicates with the seal portion. Providing the ultra-high pressure flow path and the A pressure transducer for detecting the pressure of the ultra-high pressure liquid discharged from the booster discharge hole is provided in the main body, and the booster is formed in the cylinder. A liquid supply chamber filled with the expanded liquid and a hydraulic chamber filled with the pressure oil; a piston that reciprocates between the liquid supply chamber and the hydraulic chamber; An urging means for urging the piston toward the hydraulic chamber, the piston having a large-diameter portion that slides in the cylinder, a small-diameter portion that forms a gap in the cylinder, and an axial direction in the center portion And the hydraulic chamber is formed in a gap between the cylinder and the small-diameter portion, and is formed radially in the small-diameter portion from the introduction hole. Having a through hole communicating with the hydraulic chamber It has been mounting.

Utility Model Registration No. 3181356 Japanese Patent No. 4408873

  However, both of the devices described in Patent Document 1 and Patent Document 2 employ a hydraulic pressure booster (booster), and it is easy to pressurize and control a liquid to a desired pressure accurately and with good reproducibility. It wasn't. In addition, oil may leak from the hydraulic unit of the pressure booster. Furthermore, in the said apparatus, the liquid supply pump which supplies liquid to the said pressure booster is distribute | arranged on the structure, However, Depending on a work place, the water in the said liquid supply pump will freeze in winter and operation | movement Maintenance of the apparatus has not been easy because it causes defects.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic tube expansion device that can control the pressure of a liquid to a desired pressure accurately and with high reproducibility, and can be easily maintained.

  The hydraulic pressure expansion device according to the present invention includes a liquid supply tank for storing a tube expansion solution, a pressure intensifier that increases the tube expansion solution to form an ultra-high pressure tube expansion solution, and injects the ultra-high pressure tube expansion solution into a seal portion that performs tube expansion molding. The pressure intensifier includes an electric motor, a motion conversion mechanism that converts the rotational motion of the electric motor into a reciprocating motion, and a pressure holding valve, and the ultrahigh pressure is passed through the pressure holding valve. It is the structure which sends a pipe expansion liquid to the said pipe expansion tool part.

  According to the present invention, by using an electric motor type pressure booster, it is possible to pressurize and control the expanded liquid to a desired pressure accurately and with high reproducibility. In addition, since the electric motor system is used, oil leakage does not occur unlike the hydraulic system. Furthermore, according to the present invention, since the pressure intensifier is provided with the pressure holding valve, the piping configuration is simplified, and the apparatus configuration is compact and excellent in maintainability.

  The said pipe expansion liquid points out the fluid as a pressure medium with which it uses for pipe expansion shaping | molding, for example, is water. The seal portion is a tool that supplies the tube expansion liquid, which has been increased to several thousand atmospheres, to an aqua tube, and directly expands a tube of a heat exchanger such as a boiler or a condenser from its inner surface to perform tube expansion molding. Examples of the material of the tube include iron, stainless steel, copper, and titanium. The ultra-high pressure refers to a pressure required for tube expansion molding, for example, a maximum pressure of 500 MPa.

  The present invention is characterized in that a check valve is incorporated in the pressure intensifier, and the pressure intensifier self-supplies the expanded liquid from the liquid supply tank through the check valve.

  According to the present invention, a liquid supply pump for supplying the pipe expansion liquid to the pressure booster becomes unnecessary, and the maintenance of the apparatus becomes easy. Further, the cost can be reduced by reducing the number of parts of the apparatus.

  The present invention is characterized in that the check valve is arranged at a position between the pressure holding valve and a plunger in the motion conversion mechanism.

  According to the present invention, when the ultra-high pressure pipe expanding liquid is fed to the pipe expanding tool portion, a rational arrangement configuration with little transmission loss is obtained.

  The present invention is characterized in that the pressure holding valve is at an output end of the pressure booster.

  According to the present invention, since the pressure intensifier is one in which the pressure holding valve is integrated, the piping configuration is simplified, and when sending the ultra-high pressure pipe expanding liquid to the pipe expanding tool part, A rational arrangement configuration with minimum transmission loss.

  The present invention is characterized in that a controller is provided for controlling the pressure value of the extra-high-pressure tube expansion liquid by controlling the torque of the electric motor.

  According to the present invention, an expensive pressure transducer that has been conventionally installed is not necessary, and the number of parts of the apparatus is reduced, thereby reducing the cost.

  The present invention controls the pressure value of the ultra-high pressure expanded liquid by controlling the torque of the electric motor, and controls the stroke speed of the plunger in the motion conversion mechanism by controlling the rotational speed of the electric motor. It is characterized by having a controller.

  According to the present invention, when the pressure value approaches the set pressure value, the stroke speed of the plunger in the motion conversion mechanism can be decreased by reducing the rotation speed of the electric motor. The pressure can be controlled more accurately. Also, until the plunger reaches a certain pressure value, the plunger stroke speed is increased to shorten the time until the tube expansion pressure value, or the plunger is returned quickly when the plunger is not related to pressure control. Therefore, the pipe expansion work can be efficiently performed. Furthermore, after reaching the set pressure, the set pressure is held for a certain period of time to perform tube expansion molding. Even if a small amount of water leaks during that time, the set pressure is held by moving the plunger accordingly. be able to.

  Various motors can be applied as the electric motor, and examples thereof include a servo motor, an induction motor, and a PM synchronous motor. Examples of the servo motor include an AC servo motor and a DC servo motor.

  The present invention is characterized in that the electric motor is a servo motor.

  According to the present invention, since the electric motor is a servo motor, excellent characteristics such as excellent speed response performance, large starting torque, and low torque unevenness even at low speed rotation can be obtained compared to a normal electric motor. . Then, the controller controls the current flowing through the servo motor to control the torque of the servo motor, and calculates the pressure value from the torque value of the servo motor to control the pressure. The expensive pressure transducer that has been installed is no longer necessary, and the number of parts of the device is reduced.

  The present invention is characterized in that a display device for displaying the pressure value of the ultra-high pressure tube expanding liquid is provided.

  According to the present invention, it becomes easy for an operator to grasp the pressure value of the ultra-high pressure tube expanding liquid and manage the work. The pressure value may be displayed as a numerical value or a graph. By displaying the pressure value in a graph, the operator can perform the pipe expansion work while visually confirming the transition of the pressure value in the pipe expansion work, thereby further facilitating the work management.

  The present invention is characterized in that a pneumatic control valve or an electric control valve for controlling the pressure holding valve is provided.

  According to the present invention, by making the pressure holding valve an air control system, the explosion-proof performance is enhanced and no electrical noise is generated. Further, by adopting an electric control system for the pressure holding valve, it is excellent in signal response and can perform more accurate operation.

  According to the hydraulic type pipe expanding device of the present invention, by using an electric motor type pressure booster, it is possible to pressurize and control the pipe expanding liquid to a desired pressure accurately and with good reproducibility. In addition, since the electric motor system is used, oil leakage does not occur unlike the hydraulic system. According to the present invention, since the pressure booster is an integrated unit of the pressure holding valve, the piping configuration is simplified, and the device configuration is compact and excellent in maintainability. According to the present invention, since the pressure intensifier is configured to self-supply the expanded liquid from the liquid supply tank, a liquid supply pump is not required, the apparatus is easily maintained, and the number of parts of the apparatus is reduced. Cost reduction.

  According to the hydraulic expansion device of the present invention, since the electric motor is a servo motor, the speed response performance is excellent compared to a normal electric motor, the starting torque is large, and the torque unevenness is small even at low speed rotation. Characteristics can be obtained. The controller is configured to control the pressure by calculating the pressure value from the torque value of the servo motor by controlling the torque of the servo motor by controlling the current flowing to the servo motor. The expensive pressure transducer which has been used is not necessary, and the number of parts of the apparatus is reduced, so that the cost can be reduced. In addition, since the pressure value is calculated from the torque value of the servo motor by the controller and the pressure value is displayed on the display device, the operator grasps the pressure value when the tube expansion molding is performed. Thus, the work can be easily managed. And according to this invention, it becomes an apparatus according to a use environment and a use condition clean by carrying out air control or electric control of the said pressure holding valve.

It is a fluid circuit block diagram of the hydraulic-type pipe expansion apparatus of embodiment to which this invention is applied. It is the principal part perspective view which looked at the internal structure of the pressure booster of the hydraulic-type pipe expansion apparatus of the said embodiment from the side surface side. It is the principal part arrow line view which looked at the pressure booster of the hydraulic-type pipe expansion apparatus of the said embodiment from the C line direction. It is the principal part perspective view which looked at the internal structure of the pipe expansion tool part of the hydraulic type pipe expansion apparatus of the said embodiment from the side surface side. It is the principal part perspective view which looked at the internal structure of the seal part with which the said tube expansion tool part is mounted | worn from the side surface side. It is an external view which illustrates the hydraulic type pipe expansion apparatus of embodiment to which this invention is applied.

  Specific embodiments to which the present invention is applied will be described below in detail with reference to the drawings.

(Embodiment)
FIG. 6 is an external view illustrating a hydraulic pipe expanding apparatus 1 according to an embodiment to which the present invention is applied. In the hydraulic pipe expanding device 1 of the present embodiment, a main body 2 and a pipe expanding tool part 3 are connected via a pressure-resistant hose 11 and a signal cable 12. A seal part 109 for expanding the tube is attached. The pressure hose 11 has a structure that can sufficiently withstand a water pressure of a maximum of 500 MPa.

  FIG. 1 is a fluid circuit diagram of a hydraulic pipe expanding device 1 according to an embodiment to which the present invention is applied. The hydraulic pipe expanding device 1 of this embodiment includes a pipe expanding tool part 3 for injecting an ultra-high pressure pipe expanding liquid W2 into a seal part for pipe expansion molding, and a main body 2 connected to the pipe expanding tool part 3 by a pressure hose. 2 has a liquid supply tank 6 for storing the pipe expansion liquid W1, and a pressure intensifier 4 for increasing the pressure of the pipe expansion liquid W1 in the liquid supply tank 6 to an ultrahigh pressure and outputting the ultrahigh pressure pipe expansion liquid W2 to the pipe expansion tool section 3. . The pressure booster 4 includes an electric motor 48 that is a drive source of the pressure booster, a motion conversion mechanism 49 that converts the rotational motion of the electric motor 48 into a reciprocating motion, and a pressure holding valve 42. The motion conversion mechanism 49 is configured by combining a pulley 461, a transmission belt 462 and a pulley 463, a ball screw 44, and a plunger 45. The plunger 45 is a mechanical component that causes a volume change to the expanded liquid W1 confined in a predetermined space by its reciprocating motion and pressurizes the expanded liquid W2 to an ultrahigh pressure. The pressure holding valve 42 is at the output end of the pressure booster 4. When the valve is closed, the pressure holding valve 42 holds the pressure of the pressurized ultra-high pressure expanding liquid W2 and supplies the ultra-high pressure expanding liquid W2 to the expanding tool part 3, and when the valve is opened, the ultra-high pressure expanding liquid W2 is supplied. The expanded liquid W2 is discharged to the liquid supply tank 6.

  FIG. 2 is a perspective view of the main part of the internal structure of the pressure booster 4 of the hydraulic pipe expanding device 1 of the present embodiment as viewed from the side. In the example shown in FIG. 2, a pressure holding valve 42 is directly connected to the output side of the pressure booster 4, and a check valve 43 is built in the pressure booster 4, and the pressure booster 4 is connected via the check valve 43. In this configuration, the expanded liquid W <b> 1 is supplied from the liquid supply tank 6. Reference sign A1 is air having a predetermined pressure. For example, the air pressure is adjusted in a range of 0.1 MPa to 1.0 MPa. Reference sign W1 is a normal-pressure tube expansion liquid, and reference sign W2 is an ultra-high pressure tube expansion liquid. The said pipe expansion liquid W1, W2 points out the fluid as a pressure medium with which it uses for pipe expansion shaping | molding, and is water in this embodiment. The ultra-high pressure refers to a pressure required for tube expansion molding, for example, a maximum pressure of 500 MPa.

  FIG. 3 is a cross-sectional view of the main part of the pressure booster 4 as viewed from the direction of line C in FIG. The pressure booster 4 according to the present embodiment includes a check valve 43, a plunger 45, a ball screw 44, a pulley 461, a transmission belt 462, and a pulley 463 in a housing 41 (FIG. 2). The drive source of the pressure booster 4 is an electric motor 48, and the electric motor 48 is attached to the housing 41 via a speed reducer 47 (FIG. 2). A pressure holding valve 42 is disposed on the output side of the pressure booster 4 (FIGS. 2 and 3). When the shaft of the electric motor 48 rotates, the torque is reduced by the speed reducer 47 and the torque increases, and the motion conversion mechanism 49 including the pulleys 461, 463, the transmission belt 462, the ball screw 44, and the plunger 45 is rotated by the electric motor 48. The movement is converted into a reciprocating movement of the plunger 45. Then, the expanded liquid W1 supplied from the check valve 43 is increased in pressure by the reciprocating motion of the plunger 45 to become an ultrahigh pressure expanded liquid W2, and is sent to the expanded tool part 3 through the pressure holding valve 42 (FIG. 1 to FIG. 1). FIG. 3).

  In the example shown in FIG. 2, a check valve 43 is disposed at a position between the pressure holding valve 42 and the plunger 45. The pressure holding valve 42 is at the output end (the uppermost part in FIG. 2) of the pressure booster 4.

  According to the present embodiment, the piping configuration is simplified by the pressure booster 4, and a rational arrangement configuration that minimizes transmission loss when the ultra-high pressure tube expansion liquid W2 is fed to the tube expansion tool section 3 is obtained. Become.

  According to the present embodiment, by using the electric motor type pressure booster 4, it is possible to pressurize and control the expanded liquid W <b> 1 to a desired pressure accurately and with good reproducibility. In addition, since the electric motor system is used, oil leakage does not occur unlike the hydraulic system. In the present embodiment, a servo motor is employed as the electric motor 48. This is because the servo motor 48 is superior in speed response performance as compared with a normal electric motor, and provides excellent characteristics such as a large starting torque and less torque unevenness even at low speed rotation.

  The tube expansion tool unit 3 injects the ultra-high pressure tube expansion liquid W2 pressurized by the pressure intensifier 4 into the seal unit 9 that performs tube expansion molding. In this embodiment, in order to reduce the operator's weight burden and improve workability, the gun-shaped (pistol-shaped) tube expansion tool part 3 is used (FIG. 4), and the tube expansion tool is connected via the pressure hose 11 and the signal cable 12. The part 3 and the main body 2 are connected (FIGS. 1 and 6). Reference numeral 33 shown in FIG. 4 is a swivel mechanism, and the swivel mechanism 33 is a mechanism for connecting the pressure-resistant hose 11 to the flow passage 322 in a freely rotatable manner.

  FIG. 5 is a perspective view of the main part of the internal structure of the seal part 9 attached to the tube expansion tool part 3 as viewed from the side. The seal part 9 has a tube shape. In order to join the tube 109 and the tube plate 108 of a heat exchanger such as a boiler or a condenser, the hydraulic pressure expanding device 1 supplies the liquid W2 having been increased to several thousand atmospheres to the aqua tube 107, and is super-high pressure from the inner surface of the tube. The tube 109 is expanded by directly acting at the pressure P2. A variety of seal portions 9 are prepared according to the material, shape, and size of the tube 109, and the tube 9 is detachably attached to the tube expansion tool portion 3 as an attachment.

  The main body 2 has a built-in controller 7 that controls the torque of the servo motor 48 by controlling the current that flows to the servo motor 48. The controller 7 increases the torque value of the servo motor 48 by the pressure booster 4. The pressure value of the expanded liquid W2 is calculated and the pressure is controlled (FIG. 1). According to the present embodiment, it is possible to control the pressure of the expanded liquid W2 without using an expensive pressure transducer that has been conventionally installed. In addition, the controller 7 is configured to control the rotation speed of the servo motor 48 according to the pressure value and the pipe expansion state, thereby making it possible to control the stroke speed of the plunger 48 and more accurately the pressure value in the pipe expansion molding. Can be controlled. In this embodiment, the pressure value can be controlled without using a pressure transducer, but of course, a pressure transducer may be used, and in that case, more accurate pressure control is possible.

  In this embodiment, in order to reduce the operator's weight burden and improve workability, the gun-shaped (pistol-shaped) tube expansion tool part 3 is used (FIG. 4), and the tube expansion tool is connected via the pressure hose 11 and the signal cable 12. The part 3 and the main body 2 are connected (FIGS. 1 and 6). Reference numeral 33 shown in FIG. 4 is a swivel mechanism, and the swivel mechanism 33 is a mechanism for connecting the pressure-resistant hose 11 to the flow passage 322 in a freely rotatable manner.

  FIG. 5 is a perspective view of the main part of the internal structure of the seal part 9 attached to the tube expansion tool part 3 as viewed from the side. The seal part 9 has a tube shape. In order to join the tube 109 and the tube plate 108 of a heat exchanger such as a boiler or a condenser, the hydraulic expansion device 1 supplies the liquid W2 whose pressure has been increased to several thousand atmospheres to the aqua tube 107 in the seal portion 9. The tube 109 is expanded by directly acting from the inner surface of the tube with an ultrahigh pressure P2. A variety of materials, shapes, and sizes of the seal portion 9 are prepared in accordance with the material, shape, and size of the tube 109, and the tube portion 109 is detachably attached as an attachment.

  The main body 2 has a built-in controller 7 that controls the torque of the servo motor 48 by controlling the current flowing to the servo motor 48, and the pressure when the tube 7 is expanded from the torque value of the servo motor 48 by the controller 7. A value is calculated and the pressure is controlled (FIG. 1). According to the present embodiment, an expensive pressure transducer that has been conventionally installed is not necessary, and the number of parts of the apparatus is reduced, thereby reducing the cost.

  The main body 2 is provided with a display device 8 that displays a pressure value when the tube expansion is performed. The controller 7 calculates the pressure value from the torque value of the servo motor 48 and displays the pressure value on the display device 8. (Fig. 1). According to this embodiment, since the pressure value is displayed as a number or a graph, the operator can work while easily grasping the pressure value when the tube expansion is performed. The display device 8 is a touch panel type liquid crystal screen and improves operability.

  The main body 2 is provided with a pneumatic control valve 5 for air-controlling the pressure holding valve 42, and the pressure holding valve 42 is closed by supplying air A 1 from the control valve 5, so that an ultrahigh pressure pipe expanding liquid is supplied from the pressure booster 4. W2 is injected into the tube expansion tool portion 3, and the tube 109 into which the seal portion 9 is inserted is expanded by the pressure P2 of the ultrahigh-pressure tube expansion liquid W2 injected from the tube expansion tool portion 3 into the seal portion 9. Thereafter, the control valve The air supply from 5 is stopped, the pressure holding valve 42 is opened, and the expanded liquid W1 is returned to the liquid supply tank 6 from the reduced pressure drain port 422 (FIG. 1).

  In the present embodiment, the pressure booster 4 is configured to self-supply the expanded liquid W1 from the liquid supply tank 6 (FIG. 1). This is mainly because the sealing performance of the check valve 43 of the pressure booster 4 is improved while simplifying the fluid circuit around the pressure booster 4. This embodiment eliminates the need for a liquid supply pump for supplying the expanded liquid W1 to the pressure booster 4, eliminates troubles such as freezing of water in the liquid supply pump and causing equipment failure in winter, and maintenance of the apparatus. Becomes easy. Further, the cost can be reduced by reducing the number of parts of the apparatus.

(Work procedure)
The work procedure using the hydraulic pipe expanding device 1 of this embodiment will be described below. Here, the pipe expansion liquid W1 is water. First, the power switch of the main body 2 is turned on. Next, air is supplied to the main body 2 and the ready button is pushed. Then, the air release button displayed on the touch panel 8 of the main body 2 is pressed to release air from the pressure booster 4. In the air bleeding, the servo motor 48 is operated and the plunger 45 reciprocates, and the expanded liquid W1 is self-sucked from the water supply tank 6 and discharged together with the air through the reduced pressure drain port 422 of the pressure holding valve 42. Next, the expansion pressure P2 is set on the touch panel 8. And the seal | sticker part 9 is mounted | worn with the output side (FIG. 4 left side) of the pipe expansion tool part 3, and the seal | sticker part 9 is inserted in tubes 109, such as a heat exchanger. Then, the tube expansion button 39 at the hand of the tube expansion tool unit 3 is continuously pressed (see FIG. 4), and the tube expansion operation is performed. In the pipe expanding operation, after the air A1 is supplied to the pressure holding valve 42 and the valve is closed, the pressure intensifier 4 is operated, and the ultra high pressure pipe expanding liquid W2 is supplied to the pipe expanding tool portion 3 through the ultra high pressure discharge port 421 of the pressure holding valve 42. Is supplied to the aqua tube 107 of the seal portion 9 and the high-pressure tube expansion liquid W2 is supplied, and the tube 109 is expanded by the ultra-high pressure P2. When the expansion pressure P2 is reached, the pressure P2 is maintained for several seconds (1 to 3 seconds), and then the expansion end buzzer sounds and the pressure holding valve 42 is opened to reduce the pressure. Then, after the tube expansion button 39 is released, the seal portion 9 is pulled out from the tube 109 and inserted into the next tube 109, and the tube expansion button 39 at the hand of the tube expansion tool portion 3 is kept pressed to repeat the tube expansion operation.

  In addition, this invention is not limited to the above-mentioned embodiment, A specification can be changed according to various variations. For example, in the above-described embodiment, the pressure holding valve 42 is controlled by the pneumatic control valve 5. However, the present invention is not limited to this, and the pressure holding valve 42 may be controlled by an electric control valve. . Thus, it goes without saying that the present invention can be modified as appropriate without departing from the spirit of the present invention.

1 Hydraulic expansion device,
2 body,
3 Tube expansion tool part,
4 Booster,
5 control valve,
6 Supply tank,
7 Controller,
8 Display,
9 Seal part,
11 Pressure hose,
41 Booster housing,
42 pressure holding valve,
43 Check valve,
45 plunger,
48 Electric motor (servo motor),
49 Motion conversion mechanism,
W1 expansion liquid,
W2 Super high pressure pipe expansion liquid (Ultra high pressure pipe expansion liquid)

Claims (9)

  A liquid supply tank for storing the pipe expansion liquid, a pressure intensifier that boosts the pipe expansion liquid to form an ultra-high pressure pipe expansion liquid, and a pipe expansion tool section that injects the ultra-high pressure pipe expansion liquid into a seal portion that performs pipe expansion molding. The pressure machine includes an electric motor, a motion conversion mechanism that converts the rotational motion of the electric motor into a reciprocating motion, and a pressure holding valve, and sends the ultra-high pressure pipe expanding liquid to the pipe expanding tool section through the pressure holding valve. A hydraulic tube expansion device characterized by having a liquid structure.   The hydraulic pressure tube expansion device according to claim 1, wherein the pressure booster has a built-in check valve, and the pressure booster is configured to supply the tube expansion liquid from the liquid supply tank through the check valve.   3. The hydraulic type pipe expanding device according to claim 1, wherein the check valve is disposed at a position between the pressure holding valve and a plunger in the motion conversion mechanism. 4.   The hydraulic pressure expansion device according to any one of claims 1 to 3, wherein the pressure holding valve is provided at an output end of the pressure intensifier.   5. The hydraulic pipe expanding apparatus according to claim 1, further comprising a controller that controls a pressure value of the ultrahigh-pressure pipe expanding liquid by controlling a torque of the electric motor. 6.   A controller is provided for controlling the pressure value of the ultra-high-pressure expanding liquid by controlling the torque of the electric motor, and controlling the stroke speed of the plunger in the motion conversion mechanism by controlling the rotational speed of the electric motor. 5. The hydraulic pipe expanding device according to claim 1, wherein the hydraulic pipe expanding device is provided.   The hydraulic type pipe expanding device according to any one of claims 1 to 6, wherein the electric motor is a servo motor.   8. The hydraulic type pipe expanding device according to claim 1, further comprising a display device that displays a pressure value of the ultra-high pressure pipe expanding liquid. 9.   9. The hydraulic pressure expansion device according to claim 1, further comprising a pneumatic control valve or an electric control valve for controlling the pressure holding valve.

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