Pressurizing Device

Abstract

To stably supply a working fluid.SOLUTION: A pressurizing device is equipped with pressurizing means 10 that pressurizes an article to be pressurized by the supply of a working fluid, a first cylinder mechanism 20A that supplies the working fluid in a first cylinder 21A to the pressurizing means by the output of a first driving source 23A, a second cylinder mechanism 20B that supplies the working fluid in a second cylinder 21B to the pressurizing means by the output of a second driving source 23B, and a control device 90 that controls the first driving source of the first cylinder mechanism and the second driving source of the second cylinder mechanism. The control device, when a residual condition of the working fluid in the first cylinder of the first cylinder mechanism is satisfied in a first supply state in which the working fluid is supplied to the pressurizing means only from the first cylinder mechanism, performs a shift control for shifting to a second supply state in which the working fluid is supplied to the pressurizing means only from the second cylinder mechanism.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a pressure device. [Background technology]

[0002] In a pressurizing device that takes time to increase the pressure to a pressurizing means, a servo motor and a ball screw mechanism have been used to stroke the plunger of a plunger pump having a small diameter cylinder at a low speed to supply working fluid to the pressurizing means (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-237419 A Summary of the Invention [Problem to be solved by the invention]

[0004] As the supply pressure of the working fluid required by the pressurizing means becomes higher, the inner diameter of the cylinder of the plunger pump becomes smaller, so the amount of working fluid that can be supplied from the plunger pump in one stroke operation tends to decrease. For this reason, if it is not possible to supply an amount of working fluid sufficient to raise the pressure to the target pressure of the pressurizing means in one stroke operation, the supply of working fluid is temporarily interrupted and working fluid is replenished into the cylinder of the plunger pump. Such interruptions to replenish the working fluid may cause fluctuations in the supply pressure of the working fluid, which may hinder a stable supply of the working fluid.

[0005] An object of the present invention is to stably supply a working fluid to a pressurizing means. [Means for solving the problem]

[0006] The pressure device according to the present invention comprises: A pressurizing means for pressurizing a pressurized object by supplying a working fluid; a first cylinder mechanism having a first drive source and a first cylinder, the first cylinder mechanism supplying a working fluid in the first cylinder to the pressurizing means by an output of the first drive source; a second cylinder mechanism including a second drive source and a second cylinder, the second cylinder mechanism supplying working fluid in the second cylinder to the pressurizing means by an output of the second drive source; a control device that controls the first drive source of the first cylinder mechanism and the second drive source of the second cylinder mechanism; a first switching means capable of switching between a connected state and a disconnected state of flow of the working fluid between the first cylinder mechanism and the pressurizing means; a second switching means capable of switching between a connected state and a disconnected state of the flow of the working fluid between the second cylinder mechanism and the pressurizing means; a first pressure measuring means for measuring a pressure of the working fluid in the first cylinder mechanism; a second pressure measuring means for measuring a pressure of the working fluid in the second cylinder mechanism; Equipped with In a first supply state in which the control device supplies the working fluid from the first cylinder mechanism to the pressurizing means, When a remaining amount condition of the working fluid in the first cylinder of the first cylinder mechanism is satisfied, a transition control is performed to transition to a second supply state in which the working fluid is supplied from the second cylinder mechanism to the pressurizing means. stomach, the control device, in the first supply state, sets the first switching means to a connected state and sets the second switching means to a disconnected state; When the remaining amount condition is satisfied, the pressure of the working fluid in the second cylinder mechanism is increased toward the pressure of the working fluid in the first cylinder mechanism so that the pressure measured by the first pressure measuring means and the pressure measured by the second pressure measuring means become equal, and then the transition control is performed. It is considered to be composed. Effect of the Invention

[0007] According to the present invention, it is possible to stably supply the working fluid to the pressurizing means. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing an overall configuration of a pressure device according to an embodiment of the present invention; [Diagram 2] 10 is an explanatory diagram showing a state of the first cylinder mechanism according to the position in the stroke direction of the plunger of the first or second cylinder mechanism. FIG. [Diagram 3]4 is an operational diagram showing the change over time in the internal pressure in the lower region of the hydraulic jack during operation from the start of pressurization to the end of depressurization when controlling pressurization and depressurization of the hydraulic jack. FIG. [Figure 4] 4 is a table showing the control operations of the control device for the first and second cylinder mechanisms in response to changes in the internal pressure in the lower region shown in FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0010] [Outline of pressure device] FIG. 1 is a diagram showing the overall configuration of a pressure device 1 according to this embodiment. As shown in the figure, the pressurizing device 1 includes a hydraulic jack 10 as a pressurizing means for pressurizing an object to be pressurized by supplying hydraulic oil as a working fluid, a first cylinder mechanism 20A and a second cylinder mechanism 20B for supplying hydraulic oil to the hydraulic jack 10, a hydraulic pump 32 connected to a hydraulic oil tank 33 for supplying hydraulic oil to the hydraulic jack 10, the first cylinder mechanism 20A and the second cylinder mechanism 20B, a hydraulic circuit connecting the above-mentioned components, and a control device 90 for controlling the overall configuration of the pressurizing device 1.

[0011] [Hydraulic jack] The hydraulic jack 10 comprises a fixed pressure table 11 and a movable pressure table 12 which face each other and apply pressure between them, a cylinder 13 into which hydraulic oil is supplied and discharged, a piston 14 which slides inside the cylinder 13 in the pressure direction of the movable pressure table 12, and a piston rod 15 which extends from the piston 14 to the outside of the cylinder 13 and is connected to the movable pressure table 12. The hydraulic jack 10 is of a double-acting type, and hydraulic oil is supplied and discharged between a lower region (first region) 16 and an upper region (second region) 17 inside the cylinder 13, sandwiching a piston 14. When hydraulic oil is supplied to the lower region 16 of the cylinder 13, the movable pressurizing table 12 moves toward the fixed pressurizing table 11 through the piston 14, and pressure is applied between the fixed pressurizing table 11 and the movable pressurizing table 12. When hydraulic oil is supplied to the upper region 17 of the cylinder 13, the movable pressurizing table 12 moves away from the fixed pressurizing table 11 through the piston 14, and the pressurized state is released.

[0012] The hydraulic jack 10 applies ultra-high pressure to an object to be pressurized, for example, by pressing a plurality of anvils against the object. Eight roughly cubic inner anvils and a pair of outer anvils that hold the eight inner anvils in a cubic configuration are used, and the pair of outer anvils are disposed between a fixed pressure table 11 and a movable pressure table 12 to apply pressure to the inner anvils. The corners of the inner anvils are chamfered flat, and when the eight inner anvils are assembled into a cube, the object to be pressurized is placed so that it is surrounded on all eight sides by the flat parts at the corners of each of the inner anvils located at the center of the inside. As a result, when the hydraulic jack 10 pressurizes the pair of outer anvils with high pressure, pressure is concentrated on the flat parts at the corners of the eight inner anvils, and ultra-high pressure pressurization is performed on the object to be pressurized surrounded by the flat parts. When applying ultra-high pressure as described above, it is required that the hydraulic jack 10 be raised precisely and stably over a period of time.

[0013] It should be noted that ultra-high pressure pressurization of a pressurized object using an anvil is merely one example of the use of the hydraulic jack 10, and the use is not limited thereto. It goes without saying that the hydraulic jack 10 may be used for other purposes for performing other stable pressurization.

[0014] [Hydraulic cylinder mechanism] The first cylinder mechanism 20A constitutes a plunger pump. In principle, the same reference numerals will be used to denote the same components of the first cylinder mechanism 20A and the second cylinder mechanism 20B. The first cylinder mechanism 20A comprises a hollow cylindrical first cylinder 21A, a plunger (piston) 22 that can slide inside the first cylinder 21A, a ball screw mechanism 24 as a linear motion mechanism that imparts forward and backward movement to the plunger 22, and a servo motor 23A with a reducer that serves as the first drive source for the ball screw mechanism 24.

[0015] The second cylinder mechanism 20B includes a hollow cylindrical second cylinder 21B, a plunger (piston) 22 that can slide inside the second cylinder 21B, a ball screw mechanism 24 as a linear motion mechanism that imparts forward and backward movement to the plunger 22, and a servo motor 23B with a reducer that serves as a second drive source for the ball screw mechanism 24.

[0016] The first cylinder mechanism 20A and the second cylinder mechanism 20B are both single-acting cylinder mechanisms, and hydraulic oil is supplied and discharged within areas sealed by plungers 22 in the first and second cylinders 21A and 21B. The ball screw mechanism 24 includes a ball screw 25 that is rotationally driven by servo motors 23A and 23B with speed reducers, and a movable frame 27 that includes a ball nut 26 that is screwed onto the ball screw 25. The ball screw 25 is provided parallel to the stroke direction of the plunger, and the movable frame 27 is fixedly connected to the outer end of the plunger 22 . The reducer-equipped servomotors 23A, 23B are equipped with encoders (not shown), and input the rotation amount (rotation angle) of the reducer-equipped servomotors 23A, 23B to the control device 90. Therefore, the control device 90 can control the minute rotation amount (rotation angle) of the reducer-equipped servomotors 23A, 23B. As a result, the control device 90 can control the minute movement amount of the plunger 22 in the stroke direction from the reducer-equipped servo motors 23A, 23B through the ball screw mechanism 24, and can perform precise and highly accurate control of the supply and discharge of hydraulic oil in the first and second cylinders 21A, 21B. This also precisely controls the amount of hydraulic oil supplied to the hydraulic jack 10, and therefore the pressure of the hydraulic jack 10 can be precisely and highly accurately controlled, making it possible to precisely increase, maintain, and reduce pressure for a long period of time, for example.

[0017] The ball screw mechanism 24 may impart the forward and backward movement to the first and second cylinders 21A and 21B, rather than to the plunger 22. Furthermore, the plunger of each of the cylinder mechanisms 20A and 20B is one form of a piston, and a piston that is not a plunger type may be used. Furthermore, the linear motion mechanism is not limited to a ball screw mechanism, and other linear driving means, such as a linear motor, may be used.

[0018] [Hydraulic pump] The hydraulic pump 32 is connected to a hydraulic oil tank 33 in which hydraulic oil is stored, and using a motor 34 as a driving source, can supply the hydraulic oil in the hydraulic oil tank 33 to the hydraulic jack 10, the first cylinder mechanism 20A, and the second cylinder mechanism 20B at a predetermined supply pressure.

[0019] [Hydraulic circuit] The hydraulic circuit includes a first supply valve 41 which switches the connection state from the hydraulic pump 32 to the hydraulic jack 10, a second supply valve 42 which switches the connection state from the hydraulic pump 32 to the first cylinder mechanism 20A and the second cylinder mechanism 20B, a first supply and exhaust pipe 43 which connects the hydraulic pump 32 and the first supply valve 41 to allow hydraulic oil to flow between them, a second supply and exhaust pipe 44 which connects the first supply valve 41 and the lower region 16 of the hydraulic jack 10 to allow hydraulic oil to flow between them, and a third supply and exhaust pipe 45 which connects the first supply valve 41 and the upper region 17 of the hydraulic jack 10 to allow hydraulic oil to flow between them.

[0020] Furthermore, the hydraulic circuit has a fourth supply and exhaust pipe 46 branching off from the first supply and exhaust pipe 43 and connecting the hydraulic pump 32 and the second supply valve 42 so that the hydraulic oil can flow between them, a fifth supply and exhaust pipe 47 connecting the second supply valve 42 and the first cylinder mechanism 20A so that the hydraulic oil can flow between them, a sixth supply and exhaust pipe 48 connecting the second supply valve 42 and the second cylinder mechanism 20B so that the hydraulic oil can flow between them, a seventh supply and exhaust pipe 49 connecting the first cylinder mechanism 20A and the lower region 16 of the hydraulic jack 10 so that the hydraulic oil can flow between them, and an eighth supply and exhaust pipe 50 connecting the second cylinder mechanism 20B and the lower region 16 of the hydraulic jack 10 so that the hydraulic oil can flow between them. The fifth supply and exhaust pipe 47 and the sixth supply and exhaust pipe 48 join together on the second supply valve 42 side, and the seventh supply and exhaust pipe 49 and the eighth supply and exhaust pipe 50 join together on the hydraulic jack 10 side.

[0021] The first supply valve 41 is capable of selectively connecting the lower region 16 and the upper region 17 of the hydraulic jack 10 to the hydraulic pump 32 side and the hydraulic oil tank 33 side. That is, the first supply valve 41 can be switched between a position in which the lower region 16 of the hydraulic jack 10 is connected to the hydraulic pump 32 and the upper region 17 is connected to the hydraulic oil tank 33, a position in which the lower region 16 of the hydraulic jack 10 is connected to the hydraulic oil tank 33 and the upper region 17 is connected to the hydraulic pump 32, and a position in which both the lower region 16 and the upper region 17 of the cylinder 13 of the hydraulic jack 10 are connected to the hydraulic oil tank 33.

[0022] The second supply valve 42 is capable of selectively connecting the first cylinder mechanism 20A and the second cylinder mechanism 20B to the hydraulic pump 32 side and the hydraulic oil tank 33 side. That is, the second supply valve 42 can be switched between a position where the joint end of the fifth supply and exhaust pipe 47 connected to the first cylinder mechanism 20A and the sixth supply and exhaust pipe 48 connected to the second cylinder mechanism 20B is connected to the hydraulic oil tank 33 side, and a position where the above-mentioned joint end is connected to the hydraulic pump 32 side.

[0023] Each of the supply and exhaust pipes 43 to 45, 47, and 48 is provided with a relief valve. In addition, a pilot check valve 51 is provided at the end of the second supply / discharge pipe 44 on the first supply valve 41 side, and a pressure sensor 52 is provided at the end on the lower region 16 side.

[0024] The pilot check valve 51 does not impede the flow of hydraulic oil when it is supplied from the hydraulic pump 32 to the lower region 16 of the hydraulic jack 10, and regulates the backflow of hydraulic oil from the lower region 16 of the hydraulic jack 10. However, since the pilot check valve 51 is opened when it receives the internal pressure of the third supply / discharge pipe 45, it is configured not to impede the flow of hydraulic oil pushed back from the lower region 16 to the hydraulic oil tank 33 when hydraulic oil is supplied to the upper region 17 of the hydraulic jack 10. The pressure sensor 52 detects the internal pressure of the lower region 16 of the hydraulic jack 10 and outputs the detected pressure to the control device 90 .

[0025] The fifth and sixth supply and exhaust pipes 47 and 48 are provided with tank side valves 53 and 54, which are shut-off valves, respectively. The seventh and eighth supply and exhaust pipes 49 and 50 are provided with jack side valves 55 and 56, which are shut-off valves, respectively. The jack side valve 55 functions as a first switching means capable of switching between a connected state and a disconnected state of the flow of hydraulic oil between the first cylinder mechanism 20A and the lower region 16 of the hydraulic jack 10, and the jack side valve 56 functions as a second switching means capable of switching between a connected state and a disconnected state of the flow of hydraulic oil between the second cylinder mechanism 20B and the lower region 16 of the hydraulic jack 10. These valves 53 to 56 are opened individually in response to a command from the control device 90, allowing the flow of hydraulic oil.

[0026] Further, pressure sensors 57, 58 are provided on the seventh supply / exhaust pipe 49 and the eighth supply / exhaust pipe 50 near the first and second cylinders 21A, 21B side relative to jack-side valves 55, 56 provided on each of the seventh supply / exhaust pipe 49 and the eighth supply / exhaust pipe 50. These pressure sensors 57, 58 detect the internal pressure of the first cylinder 21A of the first cylinder mechanism 20A and the internal pressure of the second cylinder 21B of the second cylinder mechanism 20B individually, and output the results to the control device 90. That is, the pressure sensor 57 functions as a first pressure measuring means that measures the pressure of the hydraulic oil in the first cylinder mechanism 20A, and the pressure sensor 58 functions as a second pressure measuring means that measures the pressure of the hydraulic oil in the second cylinder mechanism 20B.

[0027] [Control device] The control device 90 is connected to the geared servo motors 23A, 23B of the first and second cylinder mechanisms 20A, 20B, the motor 34 of the hydraulic oil tank 33, the first supply valve 41, the second supply valve 42, the tank side valves 53, 54, and the jack side valves 55, 56, and is capable of controlling the operation of these. The control device 90 is also connected to pressure sensors 52, 57, and 58, and acquires the detected pressures inside the lower region 16 of the hydraulic jack 10, the first cylinder 21A of the first cylinder mechanism 20A, and the second cylinder 21B of the second cylinder mechanism 20B. In addition, since the position of the plunger 22 in the stroke direction correlates with the amount of rotation of the output shaft of the reducer servomotors 23A, 23B, the control device 90 can obtain the position of each plunger 22 in the stroke direction from the encoder outputs of the reducer servomotors 23A, 23B of the first and second cylinder mechanisms 20A, 20B. In addition, by obtaining the position of each plunger 22 in the stroke direction from the encoder outputs of the reducer servomotors 23A, 23B of the first and second cylinder mechanisms 20A, 20B, the supply and discharge amounts of hydraulic oil by the first and second cylinder mechanisms 20A, 20B are substantially obtained.

[0028] [Operation control of pressure device] FIG. 2 is an explanatory diagram showing the state of the first or second cylinder mechanism 20A, 20B according to the position in the stroke direction of the plunger 22 of the first or second cylinder mechanism 20A, 20B (the remaining amount of hydraulic oil inside the first and second cylinders 21A, 21B). The "suction end" position of the plunger 22 shown in FIG. 2 is the position at which the plunger 22 has sucked in the most hydraulic oil, and the control device 90 performs the suction operation within a range in which the plunger 22 does not exceed the "suction end". "Just before the suction end" is the vicinity of the "suction end", and when the plunger 22 reaches "just before the suction end" during the suction of hydraulic oil, the control device 90 recognizes the approach of the "suction end". The range from the "suction end" to the "suction end" is referred to as the "suction remaining area."

[0029] The "discharge end" position of the plunger 22 shown in FIG. 2 is the position of the plunger 22 at which the most hydraulic oil is discharged, and the control device 90 performs the discharge operation within a range in which the plunger 22 does not exceed the "discharge end". "Just before the discharge end" is the vicinity of the "discharge end", and when the plunger 22 reaches "just before the discharge end" during the discharge of hydraulic oil, the control device 90 recognizes the approach of the "discharge end". The range from the "front of the discharge end" to the "discharge end" is referred to as the "residual discharge area." The range between the "before the discharge end" and the "before the suction end" is defined as the "effective movable range."

[0030] The pressurization / depressurization control of the hydraulic jack 10 executed by the control device 90 will be described. The control device 90 is characterized in that, in the pressure increase / decrease control of the hydraulic jack 10, it performs transition control to transition from a first supply state in which hydraulic oil is supplied from the first cylinder mechanism 20A to the lower region 16 of the hydraulic jack 10 to a second supply state in which hydraulic oil is supplied from the second cylinder mechanism 20B to the lower region 16 of the hydraulic jack 10 when a remaining amount condition indicating that the remaining amount of hydraulic oil in the first cylinder 21A of the first cylinder mechanism 20A is low is satisfied. In the first supply state, the hydraulic oil may be supplied only from the first cylinder mechanism 20A, and in the second supply state, the hydraulic oil may be supplied only from the second cylinder mechanism 20B.

[0031] Fig. 3 is an operational diagram showing the change over time in the internal pressure in the lower region 16 of the hydraulic jack 10 during operation from the start of pressurization to the end of depressurization during pressurization / depressurization control of the hydraulic jack 10, where the vertical axis indicates pressure and the horizontal axis indicates time. Fig. 4 is a diagram showing the control operation by the control device 90 of the first and second cylinder mechanisms 20A, 20B associated with the change in the internal pressure in the lower region 16 shown in Fig. 3 during pressurization / depressurization control of the hydraulic jack 10. In addition, in FIG. 4, "No. 1 pump" indicates the first cylinder mechanism 20A, and "No. 2 pump" indicates the second cylinder mechanism 20B.

[0032] The control device 90 detects the positions of the plungers 22 of the cylinder mechanisms 20A and 20B and performs the following operational control. When applying pressure to an object to be pressurized, the object to be pressurized is set in a state in which the object is held by a plurality of anvils against the fixed pressure table 11 and the movable pressure table 12 of the hydraulic jack 10. In addition, the control device 90 closes (OFF) the tank side valves 53, 54 in advance, controls the first supply valve 41 to connect the hydraulic pump 32 to the lower region 16 of the hydraulic jack 10, and brings the movable pressure table 12 close to the fixed pressure table 11 within a range where the hydraulic pump 32 does not pressurize the object to be pressurized.

[0033] Then, the control device 90 controls the first supply valve 41 to switch it to a position that connects both the lower region 16 and the upper region 17 of the cylinder 13 of the hydraulic jack 10 to the hydraulic oil tank 33, and controls the second supply valve 42 to connect the joining end of the fifth supply and exhaust pipe 47 and the sixth supply and exhaust pipe 48 to the hydraulic pump 32 side. Moreover, it is assumed that the first and second cylinder mechanisms 20A, 20B are both filled with hydraulic oil up to "just before the suction end."

[0034] As shown in FIGS. 3 and 4, the control device 90 closes the tank side valves 53, 54 (OFF), opens the jack side valve 55 (ON), and closes the jack side valve 56 (OFF). Then, the geared servo motor 23A of the first cylinder mechanism 20A is driven in the discharge direction to start supplying hydraulic oil to the lower region 16 of the hydraulic jack 10 (first supply state). As a result, the plunger 22 descends from the "suction end" to the "effective movable range", and the internal pressure of the lower region 16 of the hydraulic jack 10 reaches the pressure [A], which is the start pressure.

[0035] Furthermore, when the plunger 22 of the first cylinder mechanism 20A reaches "just before the discharge end", the internal pressure in the lower region 16 of the hydraulic jack 10 reaches pressure [B] (residual amount condition of the first cylinder mechanism). As a result, the control device 90 starts driving the geared servo motor 23B of the second cylinder mechanism 20B in the discharge direction while monitoring the detected pressure of the pressure sensors 57, 58, and increases the pressure inside the second cylinder 21B of the second cylinder mechanism 20B so that it becomes equal to the pressure inside the first cylinder 21A of the first cylinder mechanism 20A (start of transition control).

[0036] Then, when the plunger 22 of the first cylinder mechanism 20A reaches the "discharge remaining area", the internal pressure in the lower region 16 of the hydraulic jack 10 reaches pressure [C]. Also, at this point, the plunger 22 of the second cylinder mechanism 20B reaches the "effective movable range", and the pressure inside the second cylinder 21B of the second cylinder mechanism 20B is increased to be equal to the pressure inside the first cylinder 21A of the first cylinder mechanism 20A. As a result, the control device 90 opens (ON) the jack-side valve 56 of the second cylinder mechanism 20B. At this time, the pressure inside the second cylinder 21B of the second cylinder mechanism 20B is equal to the pressure inside the first cylinder 21A of the first cylinder mechanism 20A, so that even if the second cylinder mechanism 20B is connected, the occurrence of pressure fluctuations due to the pressurized state of the lower region 16 of the hydraulic jack 10 is suppressed.

[0037] The control device 90 continues the state in which hydraulic oil is supplied to the lower region 16 of the hydraulic jack 10 from both the first cylinder mechanism 20A and the second cylinder mechanism 20B, until a predetermined time has elapsed, by timing of a built-in timer. Then, after a predetermined time has elapsed, the control device 90 closes (OFF) the jack side valve 55 of the first cylinder mechanism 20A, opens (ON) the tank side valve 53, and drives the hydraulic pump 32 to replenish hydraulic oil into the first cylinder 21A (completion of transition control and replenishment control). The servo motor 23A with a reducer of the first cylinder mechanism 20A is controlled to rotate in the suction direction, and when the plunger 22 reaches "just before the suction end", the servo motor 23A with a reducer is stopped and the tank side valve 53 is closed (OFF). In addition, the second supply valve 42 is switched to a position where the joint end of the fifth supply and exhaust pipe 47 and the sixth supply and exhaust pipe 48 is connected to the hydraulic oil tank 33 side, and the hydraulic pump 32 is stopped.

[0038] On the other hand, the hydraulic oil is supplied to the lower region 16 of the hydraulic jack 10 only by the second cylinder mechanism 20B (second supply state), and the internal pressure in the lower region 16 of the hydraulic jack 10 reaches pressure [D].

[0039] When the internal pressure in the lower region 16 of the hydraulic jack 10 reaches the target pressure [E] in a state in which hydraulic oil is supplied only by the second cylinder mechanism 20B (second supply state), the geared servo motor 23B of the second cylinder mechanism 20B is switched to control to maintain the above pressure [E]. The control device 90 continues to control the pressure [E] until a predetermined time has elapsed as measured by a built-in timer.

[0040] Then, when the pressure [E] is maintained for a predetermined time, the control device 90 drives the geared servo motor 23B of the second cylinder mechanism 20B in the suction direction. This starts decompression in the lower region 16 of the hydraulic jack 10, and the internal pressure of the lower region 16 of the hydraulic jack 10 reaches the pressure [F].

[0041] Furthermore, when the plunger 22 of the second cylinder mechanism 20B reaches "just before the suction end", the lower region 16 of the hydraulic jack 10 reaches the pressure [G]. The control device 90 starts driving the geared servo motor 23A of the first cylinder mechanism 20A in the discharge direction, thereby increasing the pressure in the first cylinder 21A of the first cylinder mechanism 20A toward the pressure in the second cylinder 21B of the second cylinder mechanism 20B.

[0042] Then, when the plunger 22 of the first cylinder mechanism 20A reaches "just before the discharge end", the internal pressure in the lower region 16 of the hydraulic jack 10 reaches the pressure [H]. At this point, the pressure inside the first cylinder 21A of the first cylinder mechanism 20A is increased to be equal to the pressure inside the second cylinder 21B of the second cylinder mechanism 20B. As a result, the control device 90 switches the geared servo motor 23A of the first cylinder mechanism 20A to the suction direction and opens (ON) the jack side valve 55 of the first cylinder mechanism 20A. At this time, the pressure inside the first cylinder 21A of the first cylinder mechanism 20A is equal to the pressure inside the second cylinder 21B of the second cylinder mechanism 20B, so that the occurrence of pressure fluctuations due to the reduced pressure state in the lower region 16 of the hydraulic jack 10 up to that point is suppressed.

[0043] The control device 90 continues the state in which hydraulic oil is sucked from the lower region 16 of the hydraulic jack 10 by both the first cylinder mechanism 20A and the second cylinder mechanism 20B, until a predetermined time has elapsed, based on the timing of a built-in timer.

[0044] Then, after a predetermined time has elapsed, the control device 90 closes (OFF) the jack-side valve 56 of the second cylinder mechanism 20B and opens (ON) the tank-side valve 54, and the second supply valve 42 connects the joint end of the fifth supply and discharge pipe 47 and the sixth supply and discharge pipe 48 to the hydraulic oil tank 33 side. Then, it controls the geared servo motor 23B of the second cylinder mechanism 20B to rotate in the discharge direction. At this time, when the plunger 22 of the second cylinder mechanism 20B reaches "just before the discharge end", the geared servo motor 23B is stopped and the tank-side valve 54 is closed (OFF). Meanwhile, the lower region 16 of the hydraulic jack 10 is depressurized to a pressure [I].

[0045] Then, when the pressure in the lower region 16 of the hydraulic jack 10 is reduced to the same pressure [A] as the starting pressure, the geared servo motor 23A of the first cylinder mechanism 20A is stopped, and the pressure increase / decrease control is terminated.

[0046] [Technical effect of the present embodiment] As described above, in the pressurizing device 1, the control device 90 executes the transition control during the pressurization / depressurization control of the hydraulic jack 10. Therefore, even if the hydraulic jack 10 requires a high hydraulic oil supply pressure, the hydraulic oil can be supplied by taking over from the two cylinder mechanisms 20A, 20B, making it possible to provide a stable supply of hydraulic oil without interruption.

[0047] In addition, in the first supply state, the control device 90 of the pressurizing device 1 keeps the jack side valve 55 in a connected state and the jack side valve 56 in a disconnected state (pressure [A], [B] in the lower area 16 of the hydraulic jack 10 in Figures 3 and 4), and when the remaining amount condition is satisfied, increases the pressure of the hydraulic oil in the second cylinder mechanism 20B toward the pressure of the hydraulic fluid in the first cylinder mechanism 20A and then performs transition control (pressure [C] in the lower area 16 of the hydraulic jack 10 in Figures 3 and 4). Therefore, when the supply of hydraulic oil is transferred from the first cylinder mechanism 20A to the second cylinder mechanism 20B by the transition control, the occurrence of pressure fluctuations in the lower region 16 of the hydraulic jack 10 is effectively suppressed. This makes it possible to perform a more stable supply of hydraulic oil.

[0048] In addition, after the transition control, the control device 90 turns off the jack side valve 55 and controls the replenishment of hydraulic oil to the first cylinder 21A of the first cylinder mechanism 20A (pressure [D] in the lower area 16 of the hydraulic jack 10 in Figures 3 and 4). This enables the first cylinder mechanism 20A to quickly supply hydraulic oil or adjust pressure by discharging hydraulic oil when necessary without interruption due to the work of refilling hydraulic oil, allowing smooth pressure increase / decrease control of the hydraulic jack 10 and suppressing pressure fluctuations, making it possible to supply hydraulic oil or adjust pressure more stably.

[0049] Furthermore, the control device 90 substantially determines the amount of hydraulic oil supplied and discharged from the first cylinder mechanism 20A from the position of the plunger 22 determined from the encoder of the servomotor 23A with a reducer. When the position of the plunger 22 "just before the discharge end" is detected, which indicates a state in which the discharge amount has reached a specified amount, it is determined that the remaining amount condition is satisfied. Therefore, the timing for starting the transition control can be appropriately determined, and the hydraulic oil can be supplied more stably.

[0050] [others] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, the pressurizing device 1 may be configured to include a plurality of first cylinder mechanisms 20A and / or a plurality of second cylinder mechanisms 20B. In this case, when there are a plurality of first cylinder mechanisms 20A, the fifth supply and exhaust pipe 47 and the seventh supply and exhaust pipe 49 and other components provided in these supply and exhaust pipes 47, 49 may be provided individually for each first cylinder mechanism 20A. The same applies to the second cylinder mechanism 20B. Alternatively, when there are a plurality of first cylinder mechanisms 20A, these first cylinder mechanisms 20A may be connected in parallel to one fifth supply and exhaust pipe 47 and one seventh supply and exhaust pipe 49. The same applies to the second cylinder mechanism 20B. In this way, when multiple first cylinder mechanisms 20A and / or multiple second cylinder mechanisms 20B are provided, a larger amount of hydraulic oil can be supplied to and discharged from the lower region 16 of the hydraulic jack 10, and a more stable supply of hydraulic oil can be achieved even when the hydraulic jack 10 requires a high supply pressure of hydraulic oil.

[0051] The pressurizing device 1 may also be configured to include one or more cylinder mechanisms other than the first cylinder mechanism 20A and the second cylinder mechanism 20B. The other cylinder mechanisms preferably have the same configuration as the first cylinder mechanism 20A and the second cylinder mechanism 20B. In this case, it is preferable that the other cylinder mechanisms are provided with two supply and exhaust pipes identical to the fifth supply and exhaust pipe 47 and the seventh supply and exhaust pipe 49, that the same configurations as those provided in the supply and exhaust pipes 47, 49 are provided in the two supply and exhaust pipes identical to the fifth supply and exhaust pipe 47 and the seventh supply and exhaust pipe 49, and that the two supply and exhaust pipes are connected in parallel in the same way as the fifth supply and exhaust pipe 47 and the seventh supply and exhaust pipe 49 and the sixth supply and exhaust pipe 48 and the eighth supply and exhaust pipe 50.

[0052] In this case, it is preferable that the control device 90 performs transition control (the same control as the transition control described above) to transition to a supply state in which hydraulic oil is supplied from another cylinder mechanism to the lower region 16 of the hydraulic jack 10 when the remaining hydraulic oil condition in the second cylinder 21B of the second cylinder mechanism 20B (for example, the same condition as that of the first cylinder mechanism 20A) is satisfied in the second supply state. In addition, when multiple other cylinder mechanisms are provided, it is preferable to perform transition control (the same control as the transition control described above) for one other cylinder mechanism to transition to a supply state in which hydraulic oil is supplied from the other cylinder mechanism to the lower region 16 of the hydraulic jack 10 when a remaining amount condition (for example, the same condition as that of the first cylinder mechanism 20A) is satisfied.

[0053] In this way, when the configuration is provided with one or more cylinder mechanisms other than the first cylinder mechanism 20A and the second cylinder mechanism 20B, a larger amount of hydraulic oil can be supplied to and discharged from the lower region 16 of the hydraulic jack 10, and a more stable supply of hydraulic oil can be achieved even when the hydraulic oil supply pressure required for the hydraulic jack 10 is high.

[0054] Furthermore, each of the cylinder mechanisms 20A, 20B and the hydraulic jack 10 may employ a hydraulic mechanism that uses hydraulic pressure (for example, water pressure) from a liquid other than hydraulic oil. In addition, the details shown in the above embodiment can be modified as appropriate without departing from the spirit of the invention. [Explanation of symbols]

[0055] 1. Pressure device 10 Hydraulic jack (pressure means) 11 Fixed pressure table 12 Movable pressure table 13 Cylinder 14 Piston 15 Piston rod 16 Lower area 17 Upper area 18 Slides 20A First Cylinder Mechanism 20B Second cylinder mechanism 21A First Cylinder 21B No. 2 cylinder 22 Plunger (piston) 23A, 23B Servo motor with reducer (drive source) 24 Ball screw mechanism 25 Ball screw 26 Ball nut 27 Movable frame 32 Hydraulic pump 33 Hydraulic Oil Tank 34 Motor 41 First supply valve 42 Second supply valve 43~50 1st~8th supply / discharge pipe 51 Pilot Check Valve 52 Pressure Sensor 53,54 Tank side valve 55 Jack side valve (first switching means) 56 Jack side valve (second switching means) 57 Pressure sensor (first pressure measuring means) 58 Pressure sensor (second pressure measuring means) 90 Control device

Claims

1. A pressurizing means for pressurizing a pressurized object by supplying a working fluid; a first cylinder mechanism including a first drive source and a first cylinder, the first cylinder mechanism supplying a working fluid in the first cylinder to the pressurizing means by an output of the first drive source; a second cylinder mechanism including a second drive source and a second cylinder, the second cylinder mechanism supplying working fluid in the second cylinder to the pressurizing means by an output of the second drive source; a control device that controls the first drive source of the first cylinder mechanism and the second drive source of the second cylinder mechanism; a first switching means capable of switching between a connected state and a disconnected state of flow of a working fluid between the first cylinder mechanism and the pressurizing means; a second switching means capable of switching between a connected state and a disconnected state of flow of the working fluid between the second cylinder mechanism and the pressurizing means; a first pressure measuring means for measuring a pressure of the working fluid in the first cylinder mechanism; a second pressure measuring means for measuring a pressure of the working fluid in the second cylinder mechanism; Equipped with In a first supply state in which the control device supplies the working fluid from the first cylinder mechanism to the pressurizing means, performing a transition control to transition to a second supply state in which the working fluid is supplied from the second cylinder mechanism to the pressurizing means when a remaining amount condition of the working fluid in the first cylinder of the first cylinder mechanism is satisfied; the control device, in the first supply state, sets the first switching means to a connected state and sets the second switching means to a disconnected state; a pressure measuring device which, when the remaining amount condition is satisfied, increases the pressure of the working fluid in the second cylinder mechanism toward the pressure of the working fluid in the first cylinder mechanism so that the pressure measured by the first pressure measuring means and the pressure measured by the second pressure measuring means become equal, and then performs the transition control.

2. The pressurizing device according to claim 1 , wherein the control device controls the replenishment of the working fluid in the first cylinder of the first cylinder mechanism by disengaging the first switching means after the transition control.

3. 3. The pressurizing device according to claim 1, wherein the control device calculates an amount of the working fluid discharged from the first cylinder mechanism, and determines that the remaining amount condition is satisfied when the amount of the working fluid discharged reaches a specified amount.

4. The pressure applying device according to claim 1 , further comprising a plurality of the first cylinder mechanisms and / or the second cylinder mechanisms.

5. a cylinder mechanism other than the first cylinder mechanism and the second cylinder mechanism, In the second supply state, the control device 5. The pressurizing device according to claim 1, wherein when a remaining amount condition of the working fluid in the second cylinder of the second cylinder mechanism is satisfied, control is performed to transition to a supply state in which the working fluid is supplied from the other cylinder mechanism to the pressurizing means.

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