JP2006316800A - Jack device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a jack device to be used for a press machine requiring low thrust and a high speed or a low speed and high thrust, having low-bulk compact construction with lower cost by using a closed circuit type fluid supply/discharge means, namely, a fluid source of a direct drive volume control (DDV) type instead of a power unit consisting of a pump and a control valve. <P>SOLUTION: The jack device comprises a double cylinder 2, a first valve means 3, a second valve means 4, and the closed circuit type fluid supply/discharge means 5. Particularly, the double cylinder 2 consists of two large and small cylinders A, B combined in an inner and outer double fashion. The first valve means 3 and the second valve means 4 are provided for simplifying the closed circuit fluid supply/discharge means 5. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is used, for example, in a press machine that requires a high thrust at a low thrust and a low speed, and uses a closed circuit type fluid supply / discharge means, that is, a direct drive volume, without using a power unit including a pump and a control valve. The present invention relates to an improvement of a jack device using a control (DDV) type fluid source.

Conventionally, as this type of jack device, for example, those described in Patent Literature 1 to Patent Literature 3 are known.
Such a structure has a structure in which two large and small cylinders are connected vertically and a closed circuit type fluid supply / discharge means is provided for each cylinder.

JP 2004-337867 A JP 2004-337868 A JP 2004-337869 A

  However, since such a cylinder has two cylinders connected in the vertical direction, it is bulky and requires a closed circuit type fluid supply / discharge means for each cylinder. It was.

  The present invention has been devised in view of the problems described above, and a problem to be solved by the present invention is a jack device that can be formed in a compact and compact manner and can reduce costs. Is in providing.

  The jack device of the present invention basically has a large double rod type cylinder combined inside and outside, and a large double rod type cylinder and a small double rod type small rod are fixed on the fixed side and small. A double cylinder in which a large rod of a large double rod cylinder that doubles as a small cylinder of a double rod cylinder is raised and lowered to form upper and lower large fluid chambers and upper and lower small fluid chambers; A first valve means for cutting off the lower large fluid chamber, and a second valve for cutting off the upper small fluid chamber and the lower large fluid chamber, and cutting off the lower small fluid chamber and the upper large fluid chamber in synchronism with this interruption. It is characterized by comprising valve means and closed circuit type fluid supply / discharge means for supplying and discharging fluid to and from the upper small fluid chamber and the lower small fluid chamber.

The upper large fluid chamber and the lower large fluid chamber are communicated by the first valve means, and the upper small fluid chamber and the lower large fluid chamber are blocked by the second valve means, and at the same time, the lower small fluid chamber and the upper large fluid chamber are separated. After blocking, when the fluid is supplied to the lower small fluid chamber by the closed circuit type fluid pressure supply / discharge means and simultaneously the fluid is discharged from the upper small fluid chamber, the large rod is lowered at a low thrust and a high speed.
At this time, the fluid in the lower large fluid chamber is pressurized by the large piston, but since the upper large fluid chamber and the lower large fluid chamber are communicated by the first valve means, the fluid is transferred to the upper large fluid chamber. The

The upper large fluid chamber and the lower large fluid chamber are blocked by the first valve means, and the lower small fluid chamber and the upper large fluid chamber are simultaneously communicated by the second valve means. After the communication, when the fluid is supplied to the lower small fluid chamber by the closed circuit type fluid pressure supply / discharge means and at the same time the fluid is discharged from the upper small fluid chamber, the large rod is lowered at a high thrust and a low speed.
At this time, the fluid supplied to the lower small fluid chamber reaches the upper large fluid chamber and pushes down the large piston because the lower small fluid chamber communicates with the upper large fluid chamber by the second valve means. The fluid in the lower large fluid chamber is pressurized by pushing down the large piston, and the upper small fluid chamber and the lower large fluid chamber are in communication with each other by the second valve means. Discharged.

The upper large fluid chamber and the lower large fluid chamber communicate with each other by the first valve means, and the lower small fluid chamber and the lower large fluid chamber are simultaneously blocked by the second valve means. After that, when the fluid is supplied to the upper small fluid chamber by the fluid pressure supply means and simultaneously the fluid is discharged from the lower small fluid chamber, the large rod is raised at a high thrust and a low speed.
At this time, the fluid supplied to the upper small fluid chamber reaches the lower large fluid chamber and pushes up the large piston because the upper small fluid chamber and the lower large fluid chamber communicate with each other by the second valve means. The fluid in the upper large fluid chamber is pressurized by pushing up the large piston, and the lower small fluid chamber and the upper large fluid chamber are in communication with each other by the second valve means. Discharged.

The upper large fluid chamber and the lower large fluid chamber are communicated by the first valve means, and the upper small fluid chamber and the lower large fluid chamber are blocked by the second valve means, and at the same time, the lower small fluid chamber and the upper large fluid chamber are separated. After the blocking, when the fluid is supplied to the upper small fluid chamber by the closed circuit type fluid pressure supply / discharge means and simultaneously the fluid is discharged from the lower small fluid chamber, the large rod is lowered at a low thrust and a high speed.
At this time, the fluid in the upper large fluid chamber is pressurized by the large piston. However, since the upper large fluid chamber and the lower large fluid chamber are communicated by the first valve means, the fluid is transferred to the lower large fluid chamber. The

  The double cylinder is composed of a large cylinder fixed to the fixed side, a large piston slidable in the vertical direction on the large cylinder, a large upper and lower rod provided on the large piston, and a large piston and large A small cylinder formed by a rod, a small piston provided in the small cylinder so as to be slidable in the vertical direction, an upper and lower small rod provided on the small piston and having the upper one fixed to the fixed side, An upper large fluid chamber formed above the piston, a lower large fluid chamber formed below the large piston, an upper small fluid chamber formed above the small piston, and a lower piston. And a lower small fluid chamber. If it does in this way, the whole can be comprised compactly and it can install in a press machine etc. easily.

  The large piston and the small piston preferably have the same upper and lower pressure receiving areas. In this way, the fluid supply / discharge amount can be made equal, and there is no need to provide an accumulator, a prefill valve, a tank, or the like.

  The first valve means is formed in the large piston and communicates with the upper large fluid chamber and the lower large fluid chamber, the first valve body that opens and closes the first passage, and the large cylinder is slidable in the vertical direction. And a first valve rod that is connected to the first valve body and a first actuator that is provided in the small cylinder and operates the first valve rod. In this way, the length of the first passage can be shortened, the amount of fluid flowing therethrough can be reduced, and the responsiveness can be increased accordingly.

  The second valve means includes a second passage formed in the small cylinder for communicating the upper small fluid chamber and the lower large fluid chamber, and a third passage formed in the small cylinder for communicating the lower small fluid chamber and the upper large fluid chamber. And a first electromagnetic valve that opens and closes the second passage, and a second electromagnetic valve that opens and closes the third passage in synchronization with the first electromagnetic valve. If it does in this way, a 1st solenoid valve and a 2nd solenoid valve can be provided outside, and this can be maintained easily.

  The second valve means includes a second passage formed in the small cylinder for communicating the upper small fluid chamber and the lower large fluid chamber, and a third passage formed in the small cylinder for communicating the lower small fluid chamber and the upper large fluid chamber. A second valve element that opens and closes the second passage, a third valve element that opens and closes the third passage, and a second cylinder and a third valve that are slidably passed through the large cylinder and the large piston in the vertical direction. A second valve rod connected to the body and a second actuator provided on the small cylinder to operate the second valve rod are preferably provided. If it does in this way, while being able to shorten the length of a 2nd channel | path or a 3rd channel | path, the amount of fluids which flow through this can be decreased, and responsiveness can be improved so much. In addition, since the two valve bodies are operated by a single actuator, the structure is simplified and the cost can be reduced.

  The closed circuit type fluid supply / discharge means includes a motor that is driven to rotate, a pump that is rotated forward and backward by the motor, a fourth passage that communicates one oil port of the pump and the upper small fluid chamber, and one of the pumps. It is preferable that a fifth passage for communicating the oil port with the lower small fluid chamber is provided. In this way, it is possible to drive even a pump smaller than the capacity of the upper small fluid chamber and the lower small fluid chamber.

  The closed circuit type fluid supply / discharge means includes a rotationally driven motor, a motion conversion mechanism that converts the rotational motion of the motor into a linear motion, a double rod cylinder that is linearly moved by the motion conversion mechanism, and a double rod cylinder It is preferable that a fourth passage communicating the one fluid chamber and the upper small fluid chamber and a fifth passage communicating the other fluid chamber of the rod type cylinder and the lower small fluid chamber are preferably provided. In this way, a high-pressure fluid can be easily generated.

According to the present invention, the following excellent effects can be achieved.
(1) A double cylinder, a first valve means, a second valve means, and a closed circuit type fluid supply / discharge means, and in particular, a combination of two large and small cylinders inside and outside double, and a first valve means And the second valve means are provided as a single closed circuit type fluid supply / discharge means.
(2) Since the two large and small cylinders are combined in an internal / external double, and the first valve means and the second valve means are provided to provide a single closed circuit type fluid supply / discharge means, cost reduction is achieved. You can plan.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic longitudinal front view showing a high-speed descending state of a jack device according to a first example of the present invention. FIG. 2 is a view similar to FIG. FIG. 3 is a view similar to FIG. FIG. 4 is a view similar to FIG.

  The jack device 1 is mainly composed of a double cylinder 2, a first valve means 3, a second valve means 4, and a closed circuit type fluid pressure supply / discharge means 5, and is applied to, for example, a press machine. In this example, the jack apparatus 1 is installed vertically with the upper side of each figure as an upper side.

  In the double cylinder 2, the large and small double rod cylinders A and B are combined inside and outside, and the large cylinder 6 of the large double rod cylinder A and the small rod 11 of the small double rod cylinder B are fixed to the fixed side. The large rod 8 of the large double rod cylinder A that doubles as the small cylinder 9 of the small double rod cylinder B is moved up and down to form upper and lower large fluid chambers 12 and 13 and upper and lower small fluid chambers 14 and 15. In this example, a large cylinder 6 fixed to a fixed side C such as a frame of a press machine, a large piston 7 provided on the large cylinder 6 so as to be slidable in the vertical direction, and an upper and lower provided on the large piston 7 A large cylinder 8, a small cylinder 9 formed by the large piston 7 and the upper and lower large rods 8, a small piston 10 slidably provided in the small cylinder 9 in the vertical direction, and a small piston 10. The upper and lower small rods 11 whose upper side is fixed to the fixed side C, the upper large fluid chamber 12 formed on the upper side of the large piston 7, and the lower large fluid chamber formed on the lower side of the large piston 7 13, an upper small fluid chamber 14 formed on the upper side of the small piston 10, and a lower small fluid chamber 15 formed on the lower side of the small piston 10.

The lower large rod 8 is hollow so as to contain the lower small rod 11, and the lower end is closed by a lid 16. Although not shown, a press die or the like is attached to the lid body 16.
The large piston 7 and the small piston 10 have the same upper and lower pressure receiving areas. In other words, the upper and lower pressure receiving areas of the large piston 7 are made equal by making the upper and lower large rods 8 have the same diameter, and the upper and lower pressure receiving forces of the small piston 10 are made by making the upper and lower small rods 11 have the same diameter. The areas are equal.
The large cylinder 6, the large piston 7 and the upper and lower large rods 8 form a large double rod type cylinder A, and the small cylinder 9, the small piston 10 and the upper and lower small rods 11 form a small double rod type cylinder B. Therefore, the large piston 7 and the upper and lower large rods 8 also serve as the small cylinder 9.

The first valve means 3 cuts off the upper large fluid chamber 12 and the lower large fluid chamber 13 of the double cylinder 2. In this example, the first valve means 3 is formed in the large piston 7 and is formed in the upper large fluid chamber 12 and the lower large fluid. A first passage 17 communicating with the chamber 13, a first valve body 18 for opening and closing the first passage 17, and a first valve body 18 slidably passed through the large cylinder 6 and connected to the first valve body 18. A valve rod 19 and a first actuator 20 provided on the small cylinder 9 to operate the first valve rod 19 are provided.
A plurality of (two) first passages 17 are formed in the circumferential direction of the large piston 7 in the axial direction.
The first valve body 18 is provided in the upper large fluid chamber 12 and has a globe valve type. The first valve body 18 faces the first passage 17 and is provided in the same number (two) as the first passage 17. The valve opening position for opening and the valve closing position for closing the first passage 17 can be taken.
A plurality of (two) first valve rods 19 are provided in response to the first valve body 18, and the first valve body 18 is slidably connected (pin-coupled) to the lower end of the first valve rod 19 to provide a large cylinder. The upper wall of 6 is slidably penetrated in the vertical direction.
The first actuator 20 is an air cylinder, and the same number (two) as the first valve rod 19 is provided on the upper portion of the upper large rod 8 forming the small cylinder 9 via the bracket 21, and the piston rod is attached to the piston rod. The first valve rod 19 is connected. Although not shown, the first actuator 20 is connected to a pressurized air generation source via a control valve, and is controlled by the control valve.

The second valve means 4 disconnects the upper small fluid chamber 14 and the lower large fluid chamber 13 and disconnects the lower small fluid chamber 15 and the upper large fluid chamber 12 in synchronization with this disconnection. In the example, the second passage 22 is formed in the small cylinder 9 to communicate the upper small fluid chamber 14 and the lower large fluid chamber 13, and the lower small fluid chamber 15 is communicated with the upper large fluid chamber 12 formed in the small cylinder 9. And a second electromagnetic valve 25 that opens and closes the third passage 23 in synchronization with the first electromagnetic valve 24.
The second passage 22 and the third passage 23 are bored in the small cylinder 9, and a part thereof is formed outside the pipe by piping.
The first electromagnetic valve 24 and the second electromagnetic valve 25 are provided outside the small cylinder 9 or the like, and are interposed in the piping portions of the second passage 22 and the third passage 23. Although not shown, both solenoid valves 24 and 25 have their solenoids connected to a power source via a controller in order to open and close in synchronization.

The closed circuit type fluid supply / discharge means 5 supplies and discharges fluid to and from the small upper fluid chamber 14 and the lower small fluid chamber 15. In this example, the motor 26 is driven to rotate, and is rotated forward and backward by the motor 26. , A fourth passage 28 that communicates one oil port of the pump 27 with the upper small fluid chamber 14, and a fifth passage 29 that communicates the other oil port of the pump 27 and the lower small fluid chamber 15. ing.
The motor 26 is a servo motor that is an electric motor, and is provided on the fixed side C. Although not shown, the motor 26 is connected to a power source via a controller, and the rotation direction and the rotation speed are controlled by the controller.
The pump 27 is a two-way discharge type constant displacement hydraulic pump, and is provided on the fixed side C.
The fourth passage 28 and the fifth passage 29 are formed in the small piston 10 and the small rod 11, and a part thereof is formed outside these depending on the piping.

Thus, between the large cylinder 6 and the large piston 7, between the large cylinder 6 and the large rod 8, between the small cylinder 9 and the small piston 10, between the small cylinder 9 and the small rod 11, the large cylinder. A sealing material is interposed at each sliding portion between 6 and the first valve stem 18.
Upper large fluid chamber 12, lower large fluid chamber 13, upper small fluid chamber 14, lower small fluid chamber and 15, first passage 17, second passage 22, third passage 23, fourth passage 27, fifth passage 28, etc. Is filled with fluid such as hydraulic oil.

Next, the operation will be described based on such a configuration.
1 to 4 illustrate operations when the jack apparatus 1 is applied to a press machine.

As shown in FIG. 1, the upper large fluid chamber 12 and the lower large fluid chamber 13 are communicated by opening the first valve body 18 of the first valve means 3, and the first electromagnetic valve of the second valve means 4. The upper small fluid chamber 14 and the lower large fluid chamber 13 are shut off by closing the valve 24 and the second electromagnetic valve 25, and at the same time the lower small fluid chamber 15 and the upper large fluid chamber 12 are shut off, and then closed circuit type. When the fluid is supplied to the lower small fluid chamber 15 by the pump 27 of the fluid supply / discharge means 5 and simultaneously the fluid is discharged from the upper small fluid chamber 14, the large rod 8 is lowered at a low thrust and a high speed.
At this time, the fluid in the lower large fluid chamber 13 is pressurized by the large piston 7, but the upper large fluid chamber 12 and the lower large fluid chamber 13 are communicated by the first valve means 3. It is transferred to the fluid chamber 12.

As shown in FIG. 2, the upper large fluid chamber 12 and the lower large fluid chamber 13 are shut off by closing the first valve body 18 of the first valve means 3, and the first electromagnetic valve of the second valve means 4. The upper small fluid chamber 14 and the lower large fluid chamber 13 are communicated by opening the 24 and the second electromagnetic valve 25, and at the same time the lower small fluid chamber 15 and the upper large fluid chamber 12 are communicated, then the closed circuit type When the fluid is supplied to the lower small fluid chamber 15 by the pump 27 of the fluid supply / discharge means 5 and simultaneously the fluid is discharged from the upper small fluid chamber 14, the large rod 8 is lowered at a high thrust and a low speed.
At this time, the fluid supplied to the lower small fluid chamber 15 is in communication with the lower small fluid chamber 15 and the upper large fluid chamber 12 by the second electromagnetic valve 25 of the second valve means 4. 12 is reached and the large piston 7 is pushed down. The fluid in the lower large fluid chamber 13 is pressurized by pushing down the large piston 7, and the upper small fluid chamber 14 and the lower large fluid chamber 13 are communicated by the first electromagnetic valve 24 of the second valve means 4. Then, after reaching the upper small fluid chamber 14, it is discharged from here.

As shown in FIG. 3, by closing the first valve body 18 of the first valve means 3, the upper large fluid chamber 12 and the lower large fluid chamber 13 are shut off, and the first electromagnetic valve of the second valve means 4 is used. The upper small fluid chamber 14 and the lower large fluid chamber 13 are communicated by opening the 24 and the second electromagnetic valve 25, and at the same time the lower small fluid chamber 15 and the upper large fluid chamber 12 are communicated, then the closed circuit type When the fluid is supplied to the upper small fluid chamber 14 by the pump 27 of the fluid supply / discharge means 5 and the fluid is discharged from the lower small fluid chamber 15 at the same time, the large rod 8 is raised at a high thrust and a low speed.
At this time, the fluid supplied to the upper small fluid chamber 14 is in communication with the upper small fluid chamber 14 and the lower large fluid chamber 13 by the first electromagnetic valve 24 of the second valve means 4. 13 is reached and the large piston 7 is pushed up. The fluid in the upper large fluid chamber 12 is pressurized by pushing up the large piston 7, and the lower small fluid chamber 15 and the upper large fluid chamber 12 are communicated by the second electromagnetic valve 25 of the second valve means 4. Then, after reaching the lower small fluid chamber 15, it is discharged from here.

As shown in FIG. 4, the upper large fluid chamber 12 and the lower large fluid chamber 13 are communicated by opening the first valve body 18 of the first valve means 3, and the first electromagnetic of the second valve means 4. By closing the valve 24 and the second solenoid valve 25, the upper small fluid chamber 14 and the lower large fluid chamber 13 are shut off, and at the same time the lower small fluid chamber 15 and the upper large fluid chamber 12 are shut off, and then the closed circuit is closed. When the fluid is supplied to the upper small fluid chamber 14 by the pump 27 of the mold fluid supply / discharge means 5 and the fluid is discharged from the lower small fluid chamber 15 at the same time, the large rod 8 is raised and lowered at a low thrust and a high speed.
At this time, the fluid in the upper large fluid chamber 12 is pressurized by the large piston 7, but the upper large fluid chamber 12 and the lower large fluid chamber 13 are communicated by the first valve means 3. The fluid chamber 13 is transferred.

  When the discharge direction of the pump 27 of the closed circuit type fluid supply / exhaust means 5 is switched from the state of FIG. 4, it can be returned to the state of FIG. 1, and such a series of operations are repeated.

  In this example, the state shown in FIGS. 1 and 4 is low thrust and high speed movement, that is, fast-forwarding is performed, and the state shown in FIGS. 2 and 3 is low speed and high thrust movement, that is, pressurization is performed. It is. These strokes can be arbitrarily changed depending on the operation timing of the first valve body 18 of the first valve means 3 and the first electromagnetic valve 24 and the second electromagnetic valve 25 of the second valve means 4.

Such a thing has the following advantages.
(1) Since a rapid feed mechanism is built in and fluid is circulated inside during fast feed, no prefill valve is required.
(2) Since the amount of fluid entering and exiting is the same for both rapid traverse and pressurization, a closed circuit without a tank can be achieved.
(3) It is possible to switch between rapid feed and pressurization at an arbitrary position by switching the direction of the fluid inside, and it is possible to perform subtle pressure increase and pressure reduction control by controlling the flow rate of the fluid.
(4) When ascending, switching between high speed and low speed can be easily performed by switching the direction of fluid inside.
(5) Since the pump is operated only when the double cylinder is operated, tanks and control valves are not required, and energy saving, low noise, low heat generation, and space saving are possible.

Next, a second example of the present invention will be described with reference to FIG.
FIG. 5 is a schematic longitudinal sectional front view showing a jack device according to a second example of the present invention.
In the second example, the second valve means 4 is different from the first example.
That is, the second valve means 4 is formed in the small cylinder 9 to communicate the upper small fluid chamber 14 and the lower large fluid chamber 13, and the second valve means 4 is formed in the small cylinder 9 to be connected to the lower small fluid chamber 15 and the upper small fluid chamber 15. A third passage 23 that communicates with the large fluid chamber 12, a second valve body 30 that opens and closes the second passage 22, a third valve body 31 that opens and closes the third passage 23, and the large cylinder 6 and the large piston 7. A second valve rod 32 that is slidably penetrated in the direction and connected to the second valve body 30 and the third valve body 31, and a second actuator 33 that is provided in the small cylinder 9 and operates the second valve rod 32. And.

The second valve element 30 is provided in the upper large fluid chamber 12 and is in the form of a slide valve. The second valve element 30 has an annular shape and is slidably fitted on the outer side of the upper large rod 8, which is the small cylinder 9. A valve opening position for opening the passage 22 and a valve closing position for closing the second passage 22 can be taken.
The third valve body 31 is provided in the lower large fluid chamber 13 and is in the form of a slide valve. The third valve body 31 has an annular shape and is slidably fitted on the outer side of the lower large rod 8 which is the small cylinder 9. A valve opening position for opening the passage 23 and a valve closing position for closing the third passage 23 can be taken.
Only a plurality (two) of the second valve rods 32 are provided, and the opening and closing of the second valve body 30 and the opening and closing of the third valve body 31 are connected to synchronize with each other and do not interfere with the first passage 17. Similarly, the large piston 7 and the upper wall of the large cylinder 6 are slidably penetrated in the vertical direction.
The second actuator 33 is an air cylinder, and the same number (two) as the second valve rod 32 is provided on the bracket 21 provided on the upper portion of the upper large rod 8 which is the small cylinder 9, and the piston rod is provided. Is connected to the second valve stem 32. Although not shown, the second actuator 33 is connected to a pressurized air generation source via a control valve, and is controlled by the control valve.

Next, a third example of the present invention will be described with reference to FIG.
FIG. 6 is a schematic longitudinal sectional front view showing a jack device according to a third example of the present invention.
In the third example, the closed circuit type fluid supply / discharge means 5 is different from the first example.
That is, the closed circuit type fluid supply / discharge means 5 includes a motor 34 that is rotationally driven, a motion conversion mechanism 35 that converts the rotational motion of the motor 34 into a linear motion, and a double rod type that is linearly moved by the motion conversion mechanism 35. The cylinder 36, the fourth passage 28 that communicates with one fluid chamber 37 of both rod type cylinders 36 and the upper small fluid chamber 14, and the other fluid chamber 38 of both rod type cylinders 36 communicates with the lower small fluid chamber 15. And a fifth passage 29.
The maximum capacities of the fluid chamber 37 and the fluid chamber 38 are equal to or greater than the maximum capacities of the upper small fluid chamber 14 and the lower small fluid chamber 15, and both dead center positions of the double rod type cylinder 36 and the small double rod type cylinder B are used. Should be placed in sync.

Next, a fourth example of the present invention will be described with reference to FIG.
FIG. 7 is a schematic longitudinal sectional front view showing a jack device according to a fourth example of the present invention.
In the fourth example, the second valve means 4 and the closed circuit type fluid supply / discharge means 5 are different from the first example.
That is, the second valve means 4 is formed in the small cylinder 9 to communicate the upper small fluid chamber 14 and the lower large fluid chamber 13, and the second valve means 4 is formed in the small cylinder 9 to be connected to the lower small fluid chamber 15 and the upper small fluid chamber 15. The third passage 23 for communicating the large fluid chamber 12, the second valve body 30 for opening and closing the second passage 22, the third valve body 31 for opening and closing the third passage 23, the large cylinder 6 and the large piston 7 A second valve rod 32 that is slidably penetrated in the direction and connected to the second valve body 30 and the third valve body 31, and a second actuator 33 that is provided in the small cylinder 9 and operates the second valve rod 32. The closed circuit type fluid supply / discharge means 5 includes a motor 34 that is rotationally driven, a motion conversion mechanism 35 that converts the rotational motion of the motor 34 into a linear motion, and a linear motion that depends on the motion conversion mechanism 35. One rod type cylinder 36 and one rod type cylinder 36 A fourth passage 28 that communicates the fluid chamber 37 and the upper small fluid chamber 14, and a fifth passage 29 that communicates the other fluid chamber 38 of the rod type cylinder 36 and the lower small fluid chamber 15 are provided.

In the above example, the jack device 1 has been vertically oriented, but is not limited thereto, and may be, for example, horizontally or obliquely.
The motor 26 is an electric motor in the previous example, but is not limited thereto, and may be an air motor, for example.
In the previous example, the first valve means 3 has the first passage 17 formed in the large piston 7.
In the previous example, the first valve means 3 includes the first valve body 18, the first valve rod 19, and the first actuator 20. However, the first valve means 3 is not limited to this. For example, an electromagnetic valve or the like may be used. good.
In the first and second examples, the second valve means 4 uses the two electromagnetic valves 24 and 25. However, the second valve means 4 is not limited to this, and for example, a single electromagnetic valve or the like may be used.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic longitudinal front view showing a high-speed descending state of a jack device according to a first example of the present invention. The same figure as FIG. 1 which shows a low-speed descent | fall state. The same figure as FIG. 1 which shows a low-speed raise state. The same figure as FIG. 1 which shows a high-speed raise state. The rough longitudinal front view which shows the jack apparatus which concerns on the 2nd example of this invention. The schematic longitudinal front view which shows the jack apparatus which concerns on the 3rd example of this invention. FIG. 6 is a schematic longitudinal front view showing a jack device according to a fourth example of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Jack apparatus, 2 ... Double cylinder, 3 ... 1st valve means, 4 ... 2nd valve means, 5 ... Closed circuit type fluid supply / discharge means, 6 ... Large cylinder, 7 ... Large piston, 8 ... Large rod, DESCRIPTION OF SYMBOLS 9 ... Small cylinder, 10 ... Small piston, 11 ... Small rod, 12 ... Upper large fluid chamber, 13 ... Lower large fluid chamber, 14 ... Upper small fluid chamber, 15 ... Lower small fluid chamber, 16 ... Cover, 17 ... First passage, 18 ... First valve body, 19 ... First valve rod, 20 ... First actuator, 21 ... Bracket, 22 ... Second passage, 23 ... Third passage, 24 ... First solenoid valve, 25 ... First Two solenoid valves, 26 ... motor, 27 ... fluid pressure pump, 28 ... fourth passage, 29 ... fifth passage, 30 ... second valve body, 31 ... third valve body, 32 ... second valve rod, 33 ... first Two actuators, 34 ... motor, 35 ... motion conversion mechanism, 36 ... double rod cylinder, 37 ... fluid chamber, 38 ... fluid chamber, A ... large Double rod type cylinder, B ... small double rod type cylinder, C ... fixed side.

Claims (8)

A large double rod that combines a large double rod type cylinder with a large double rod type cylinder and a small double rod type cylinder with the small rod of the small double rod type cylinder fixed to the fixed side. Double cylinder in which the large rod of the cylinder is raised and lowered to form upper and lower large fluid chambers and upper and lower small fluid chambers, and first valve means for cutting off the upper large fluid chamber and the lower large fluid chamber of the double cylinder And a second valve means that cuts off the upper small fluid chamber and the lower large fluid chamber and cuts off the lower small fluid chamber and the upper large fluid chamber in synchronism with the break, and the upper small fluid chamber and the lower small fluid A jack apparatus comprising: a closed circuit type fluid supply / discharge means for supplying and discharging fluid to and from a chamber. The double cylinder is composed of a large cylinder fixed to the fixed side, a large piston slidable in the vertical direction on the large cylinder, a large upper and lower rod provided on the large piston, and a large piston and large A small cylinder formed by a rod, a small piston provided in the small cylinder so as to be slidable in the vertical direction, an upper and lower small rod provided on the small piston and having the upper one fixed to the fixed side, An upper large fluid chamber formed above the piston, a lower large fluid chamber formed below the large piston, an upper small fluid chamber formed above the small piston, and a lower piston. The jack device according to claim 1, further comprising a lower small fluid chamber. The jack device according to claim 1, wherein the large piston and the small piston have equal upper and lower pressure receiving areas. The first valve means is formed in the large piston and communicates with the upper large fluid chamber and the lower large fluid chamber, the first valve body that opens and closes the first passage, and the large cylinder is slidable in the vertical direction. The jack device according to claim 1, further comprising: a first valve rod that is passed through the first valve body and connected to the first valve body; and a first actuator that is provided in the small cylinder and operates the first valve rod. The second valve means includes a second passage formed in the small cylinder for communicating the upper small fluid chamber and the lower large fluid chamber, and a third passage formed in the small cylinder for communicating the lower small fluid chamber and the upper large fluid chamber. The jack device according to claim 1, further comprising: a first electromagnetic valve that opens and closes the second passage; and a second electromagnetic valve that opens and closes the third passage in synchronization with the first electromagnetic valve. The second valve means includes a second passage formed in the small cylinder for communicating the upper small fluid chamber and the lower large fluid chamber, and a third passage formed in the small cylinder for communicating the lower small fluid chamber and the upper large fluid chamber. A second valve element that opens and closes the second passage, a third valve element that opens and closes the third passage, and a second cylinder and a third valve that are slidably passed through the large cylinder and the large piston in the vertical direction. The jack device according to claim 1, further comprising: a second valve rod connected to the body; and a second actuator provided on the small cylinder to operate the second valve rod. The closed circuit type fluid supply / discharge means includes a motor that is driven to rotate, a pump that is rotated forward and backward by the motor, a fourth passage that communicates one oil port of the pump and the upper small fluid chamber, and one of the pumps. The jack device according to claim 1, further comprising a fifth passage for communicating the oil port with the lower small fluid chamber. The closed circuit type fluid supply / discharge means includes a rotationally driven motor, a motion conversion mechanism that converts the rotational motion of the motor into a linear motion, a double rod cylinder that is linearly moved by the motion conversion mechanism, and a double rod cylinder The jack according to claim 1, further comprising: a fourth passage communicating the one fluid chamber and the upper small fluid chamber, and a fifth passage communicating the other fluid chamber of the rod type cylinder and the lower small fluid chamber. apparatus.

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