JPH0112964B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an amplitude control device for a hydraulic piston in a variable vibration hydraulic oscillator.

The present applicant has long discovered that by the interaction between a spool in a pilot valve that receives constant pressure and alternating pressure from both sides, and a hydraulic piston that receives constant pressure and alternating pressure from both sides in a cylinder, The hydraulic piston is caused to vibrate, and the amplitude of the hydraulic piston is made variable by slidingly adjusting a sliding liner between the cylinder and the hydraulic piston to accommodate the vibration of the hydraulic piston. We have been conducting research on variable amplitude hydraulic oscillators, and have already filed a patent application for some of our results (patent application filed in 1983).
−142498).

The present invention provides such a variable amplitude hydraulic oscillator,
It is an object of the present invention to provide an amplitude control device that is easy to handle and can be operated remotely.

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

The drawings are longitudinal sectional views of a variable amplitude hydraulic oscillator equipped with the amplitude control device of the present invention, in which FIG. 1 shows the amplitude adjusted to the minimum, and FIG. 2 shows the amplitude adjusted to the maximum. .

In the figure, reference numeral 1 denotes a variable amplitude hydraulic oscillator, which includes a pilot valve 2, a cylinder 3, a hydraulic piston 4, a variable valve 5, and a remote control valve 6. 7
A spool is slidably built into the pilot valve 2, and a supply/discharge chamber 8 is an annular groove formed in the middle of the spool 7. Reference numerals 9 and 10 are a small diameter operating rod and a large diameter operating rod that press both ends of the spool 7, respectively. 11 and 12 are small diameter operating rods 9, respectively.
and a constant pressure chamber and an alternating pressure chamber into which pressure oil is introduced into the end faces of the large-diameter operating rod 10. The side wall where the pilot valve 2 is attached to the cylinder 3 is provided with an oil supply hole 13, a communication hole 14, and an oil drain hole 15.
moves downward as shown in Figure 2, the supply/discharge chamber 8
The communication hole 14 and the oil drain hole 15 communicate with each other through the oil supply and discharge chamber 8, and when the spool 7 moves upward as shown in FIG. ing. A fixed liner 16 and a sliding liner 17 each having a large diameter part and a small diameter part are provided between the cylinder 3 and the hydraulic piston 4 on the lower constant pressure side and the upper alternating pressure side of the cylinder 3, respectively. That is, the lower part of the hydraulic piston 4 is connected to the small diameter part 18 of the fixed liner 16, the central spool part 19 of the hydraulic piston 4 is connected to the large diameter part of the fixed liner 16 and the large diameter part of the sliding liner 17, and the upper part of the hydraulic piston 4 is connected to the small diameter part 18 of the fixed liner 16. They are each slidably fitted into the small diameter portion 20 of the sliding liner 17. Spool portion 19 of hydraulic piston 4, fixed liner 16, and sliding liner 1
7, a constant pressure chamber 21 with a small pressure receiving area and an alternating pressure chamber 22 with a large pressure receiving area are formed, respectively.

Reference numeral 23 denotes a communication chamber consisting of an annular groove formed in the spool portion 19 of the hydraulic piston 4. Each liner 1
Brake chambers 24 and 25 are formed at the stepped portions of the large and small diameter portions 6 and 17, that is, at the lower end of the constant pressure chamber 21 and at the upper end of the alternating pressure chamber 22, respectively. 26 and 27 are the spool portion 1 of the hydraulic piston 4
Brake step portions provided at both ends of the brake pad 9 are designed to trap oil when entering the brake chambers 24 and 25, respectively. An oil chamber 28 is formed between the sliding liner 17 and the cylinder 3 near the upper opening end of the sliding liner 17 . The large diameter portion of the fixed liner 16 is provided with an oil supply port 29 that opens at the lower part of the constant pressure chamber 21, an oil drain port 30 that opens in the middle, and a communication port 31 that opens at the upper end. A communication port 32 that opens at the top of the alternating pressure chamber 22 and an oil supply port 33 that opens toward the lower opening end of the large diameter portion are provided in the large diameter portion of the hydraulic piston 4. The oil supply port 33 and the communication port 31 communicate with each other via the communication chamber 23 (see FIG. 1), and when the hydraulic piston 4 moves downward, the communication port 31 and the oil drain port 30 communicate with each other via the communication chamber 23. It is designed to. 34 is a spool slidably built into the variable valve 5, and 35 is a supply/discharge chamber consisting of an annular groove formed in the middle of the spool 34. Reference numerals 36 and 37 are a small-diameter operating rod and a large-diameter operating rod that press both ends of the spool 34, respectively. 38
and 39 are the small diameter operating rod 36 and the large diameter operating rod 3, respectively.
They are a constant pressure chamber and an adjusting pressure chamber into which pressure oil is introduced into the end face with 7. The side wall where the variable valve 5 is attached to the cylinder 3 is provided with an oil supply hole 41 with a built-in check valve 40, a communication hole 42, and an oil drain hole 43.
When the spool 4 moves upward, the communication hole 42 and the oil drain hole 43 communicate with each other through the supply and discharge chamber 35, and when the spool 34 moves downward, the communication hole 42 and the oil supply hole 41 communicate with each other through the supply and discharge chamber 35, The communication hole 42 is designed to be blocked from both the oil supply hole 41 and the oil drain hole 43 at the neutral position. The remote control valve 6 has a cylinder 44, a piston 45, and a handle 46. 47 is an oil chamber formed by the cylinder 44 and piston 45. An oil supply pipe connection port 48, an oil drain pipe connection port 49, and a variable valve operation pipe connection port 50 communicating with the oil chamber 47 of the remote control valve 6 are provided on the upper end surface of the cylinder 3. 51 is a supply oil path,
Connect the oil supply pipe connection port 48 to the constant pressure chamber 1 of the pilot valve 2.
1, the oil supply hole 13, the oil supply port 29 of the fixed liner 16, and the oil supply port 3 of the sliding liner 17.
3 and a hole 38' communicating with the constant pressure chamber 38 of the variable valve 5 and an oil supply hole 41. Reference numeral 52 is a drain oil passage, and the drain oil pipe connection port 49 is connected to the pilot valve 2.
The oil drain hole 15 of the fixed liner 16 communicates with the oil drain hole 30 of the fixed liner 16 and the oil drain hole 43 of the variable valve 5. Reference numeral 53 denotes a piston operating oil passage, which communicates the communication hole 14 of the pilot valve 2 with the communication port 32 of the sliding liner 17. Reference numeral 54 denotes a spool operating oil passage, which has a hole 12' communicating with the alternating pressure chamber 12 of the pilot valve 2.
is communicated with the communication port 31 of the fixed liner 16.
55 is an oil passage for operating the sliding liner, and the variable valve 5
The communication hole 42 of the cylinder 3 communicates with the hole 28' which communicates with the oil chamber 28 of the cylinder 3. Numeral 56 is a variable valve operating oil passage, which communicates the variable valve operating pipe connection port 50 with the hole 39' communicating with the regulating pressure chamber 39 of the variable valve 5.
Note that 57 is a locking nut for a stopper of the sliding liner 17, and 58 is a check valve 59 that is a tank.

The variable amplitude hydraulic oscillator 1 of the present invention configured as described above is installed in a civil engineering work machine etc. that requires variable amplitude, and the oil supply pipe connection port 48 and the oil drain pipe connection port 44 of the cylinder 3 are connected as shown in the figure. It is connected to a hydraulic power source, tank, etc., and the remote control valve 6 is placed close to hand.

Therefore, when pressure oil is supplied from the hydraulic source to the supply oil passage 51 through the oil supply pipe connection port 48, the pressure oil is supplied to the hole 1.
1' and the oil supply port 29 to the constant pressure chamber 11 of the pilot valve 2 and the constant pressure chamber 21 of the cylinder 3, respectively.
As shown in FIG. 2, in the pilot valve 2, the spool 7 moves downward via the small diameter operating rod 9, and in the cylinder 3, the hydraulic piston 4 starts moving upward. . At this time, the alternating pressure chamber 22 in the cylinder 3 includes the communication port 32, the piston operating oil passage 53, the communication hole 14,
It communicates with a tank (not shown) through the supply/discharge chamber 8, the oil drain hole 15, the oil drain path 52, and the oil drain pipe connection port 49. Next, in the process of upward movement of the hydraulic piston 4, as shown in FIG. The pressure oil supplied to the oil supply port 33 is supplied to the communication chamber 23, the communication port 31, the spool operating oil path 54, and the hole 1.
2' into the alternating pressure chamber 12 of the pilot valve 2. Since the pressure receiving area of the large diameter working rod 10 is larger than the pressure receiving area of the small diameter working rod 9, the large diameter working rod 10 overcomes the pressing force of the small diameter working rod 9 and moves the spool 7 upward. When the spool 7 moves upward, the oil supply hole 13 and the communication hole 14 communicate with each other via the supply and discharge chamber 8, and the pressure oil supplied to the oil supply hole 13 is transferred to the supply and discharge chamber 8, the communication hole 14, and the piston operating oil. It is introduced into the alternating pressure chamber 22 of the cylinder 3 via the passage 53 and the communication port 32. The pressure receiving area of the hydraulic piston 4 in the alternating pressure chamber 22 is constant pressure chamber 2.
1, the hydraulic piston 4 starts to move downward. Next, in the process of downward movement of the hydraulic piston 4, the communication port 31 and the oil drain port 3
0 communicates through the communication chamber 23, the pressure oil in the alternating pressure chamber 12 of the pilot valve 2 flows through the hole 12', the spool hydraulic oil passage 54, the communication port 31, the communication chamber 23,
Discharge port 30, discharge oil path 52, and drain oil pipe connection port 4
9 to a tank (not shown), and is led to an alternating pressure chamber 1.
As the pressure inside 2 decreases, the spool 7 is pressed by the small diameter operating rod 9 and moves downward. As a result, the alternating pressure chamber 22 of the cylinder 3 communicates with the tank (not shown) as described above, and the alternating pressure chamber 22
As the internal pressure decreases, the hydraulic piston 4 is pressed by the pressure oil in the constant pressure chamber 21 and moves upward. When the hydraulic piston 4 moves upward and the brake stepped portion 27 enters the brake chamber 25, oil is sealed in the brake chamber 25 to produce a braking action. Similarly, when the hydraulic piston 4 moves downward and the brake stepped portion 26 enters the brake chamber 24, oil is sealed in the brake chamber 24 to produce a braking action. Thereafter, the above operation is repeated, and the interaction between the spool 7 in the pilot valve 2 and the hydraulic piston 4 in the cylinder 3 makes it possible to vibrate the hydraulic piston 4.

Next, in order to adjust the amplitude, it is necessary to operate the variable valve 5 to supply and discharge pressure oil from the oil chamber 28, thereby adjusting the position of the sliding liner 17. Variable valve 5
The spool 34 is constantly pressed by the small-diameter operating rod 36 loaded with pressure oil from the constant pressure chamber 38 and the large-diameter operating rod 37 loaded with the pressure oil from the adjustment pressure chamber 39. It is necessary to load the regulating pressure chamber 39 with hydraulic pressure that resists the pressing force of the small diameter operating rod 36, and in order to push up the spool 34, it is necessary to reduce the pressure in the regulating pressure chamber 39. When the spool 34 is in the neutral position or in the lower position, when the handle 46 is pulled up, the cylinder 44
The pressure in the oil chamber 47 is reduced, and the spool 34 moves upward. When the handle 46 is pulled up further, the spool 34 stops at the end of its stroke and the oil chamber 47 becomes negative pressure, so hydraulic oil is sucked from the oil tank 59. When the spool 34 moves upward, the oil drain hole 43
is opened, and the communication hole 42 and the oil drain hole 43 are connected to the supply and discharge chamber 3.
The pressure oil in the oil chamber 28 of the cylinder 3 is communicated through the hole 28', the sliding liner operating oil passage 55, the communication hole 42, the supply/discharge chamber 35, the oil drain hole 43, and the discharge oil passage 5.
2. Pressure oil is led out to a tank (not shown) through the oil drain pipe connection port 49 and introduced into the alternating pressure chamber 22 of the cylinder 3 via the pilot valve 2, which causes the sliding liner 17 to slide upward. When the sliding liner 17 moves upward by the required distance, the pressurized oil in the oil chamber 47 of the remote control valve 6 is transferred to the variable valve operating pipe connection port by pushing the handle 46 of the remote control valve 6 to the neutral position. 50, variable valve operating oil passage 56, hole 3
9' into the adjustment pressure chamber 39, and overcoming the pressing force of the small diameter operating rod 36, the large diameter operating rod 37 pushes down the spool 34 and drains the oil from the drain hole 43 of the variable valve 5.
is closed, the oil in the oil chamber 28 is trapped, and the sliding liner 17 is held in a fixed position. Further, by pushing the handle 46 of the remote control valve 6 downward from the neutral position, the spool 34 of the variable valve 5 is pressed by the large diameter operating rod 37 and moves downward from the neutral position, and the oil supply hole 41 is opened. The communication hole 42 and the oil supply hole 41 communicate with each other via the supply and discharge chamber 35, and the pressure oil supplied to the oil supply hole 41 is connected to the check valve 40 built in the oil supply hole 41, the supply and discharge chamber 35, and the communication hole. 42, it flows into the oil chamber 28 through the sliding liner operating oil passage 55 and the hole 28', and when the alternating pressure chamber 22 is at low alternating pressure, the sliding liner 17 is pressed by the pressure oil in the oil chamber 28. Slide downward. The hydraulic piston 4 enters the brake chamber 25 at the top dead center, and when high pressure is generated in the brake chamber 25, it acts to push the sliding liner 17 upward. Since the oil chamber communicates with the supply oil passage 51 via the supply/discharge chamber 35 of the spool 34, the oil chamber 28 must be connected to prevent the sliding liner 17 from moving upward when the hydraulic piston 4 enters the brake chamber 25. It is necessary to lock the oil in the check valve 4.
0 has the role of the lock. When the sliding liner 17 moves downward the required distance, by pulling up the handle 46 of the remote control valve 6 to the neutral position, the spool 34 is pushed upward to the neutral position by being pressed by the small diameter operating rod 36 as described above. The oil supply hole 41 is closed by sliding, the oil in the oil chamber 28 is trapped, and the sliding liner 17 is held at a fixed position. When the sliding liner 17 is slidably adjusted as described above,
Oil filler port 33 and brake chamber 25 for cylinder 3
As a result, the communication port 31 of the fixed liner 16 and the oil supply port 3 of the sliding liner 17 are adjusted.
3, the pressure oil supplied to the oil supply port 33 is transferred to the communication chamber 23 of the hydraulic piston 4, the communication port 31, the spool operating oil passage 54, and the hole 12'.
Through this, the timing of introducing the pilot valve 2 into the alternating pressure chamber 12 is adjusted. Since the relative position between the brake chamber 25 and the fuel filler port 33 remains unchanged, sliding adjustment of the sliding liner 17 in the direction approaching the fixed liner 16 advances the timing, thereby causing the spool 7 to move upward. As a result, the timing at which the hydraulic piston 4 starts moving in the downward direction is brought forward, and the timing at which the hydraulic piston 4 starts moving downward is also brought forward with a constant phase difference that is not related to the amplitude.
The sliding distance of the hydraulic piston 4 becomes smaller, and the amplitude becomes smaller. When the sliding liner 17 abuts the fixed liner 16, the amplitude is at a minimum, and when the sliding liner 17 abuts against the stopper locking nut 57, the amplitude is at a maximum. Therefore, pull up the handle 46 of the remote control valve 6 from the neutral position to connect the hydraulic power source (not shown) and the oil chamber 28.
By blocking the oil chamber 28 and communicating with the tank (not shown), the pressure oil in the oil chamber 28 of the cylinder 3 is led out to the tank (not shown) via the variable valve 5, and the sliding liner 17 is moved upward. sliding hydraulic piston 4
The amplitude of increases. When the handle 46 is returned to the neutral position and the oil chamber 28 is shut off from both the oil pressure source and the tank (not shown), the oil is trapped in the oil chamber 28 and the position of the sliding liner 17 is maintained, so that the amplitude remains constant. Retained. Further, by pushing down the handle 46 and communicating the hydraulic pressure source with the oil chamber 28, pressure oil is introduced into the oil chamber 28 via the variable valve 6, and the sliding liner 17 slides downward, causing the hydraulic piston 4 amplitude decreases.

The check valve 40 closes the sliding liner due to oil confinement pressure caused by the plunge of the hydraulic piston into the brake chamber 25 when pressure oil is introduced into the oil chamber 28 to cause the sliding liner 17 to slide downward. This prevents the hydraulic piston 4 from sliding upward.
This is to ensure the reversal of . The amount of displacement of the handle 46 of the remote control valve 6 from the neutral position is proportional to the amount of displacement of the piston 45, and the amount of displacement of the piston 45 is proportional to the change in the amount of oil in the oil chamber 47.
The change in the amount of oil in the adjustment pressure chamber 39 of the variable valve 5 corresponds one-to-one to the change in the amount of oil in the adjustment pressure chamber 39 of the variable valve 5, and is proportional to the sliding distance of the spool 34. Corresponding to the opening width of the hole 43,
Depending on the opening width of the oil supply hole 41 or the oil drain hole 43, the amount of pressure oil supplied to and discharged from the oil chamber 28 of the cylinder 3 per hour changes, and the sliding speed of the sliding liner 17 changes. Therefore, the amount of displacement of the handle 46 of the remote control valve 6 corresponds to the rate of change in the amplitude of the hydraulic piston 4. Note that the check valve 5 is installed in the oil chamber 47 of the remote control valve 6.
The hydraulic circuit communicated with the tank 59 via 8 is a replenishment circuit for supplying oil leakage to the oil chamber 47 during assembly and for supplying oil leakage.

As can be easily understood from what has been said above,
The amplitude control device for the variable amplitude hydraulic oscillator of the present invention is such that the amplitude of the hydraulic piston can be arbitrarily adjusted by remote control, and the amount of displacement of the handle of the remote control valve can correspond to the rate of change in the amplitude of the hydraulic piston. When used in hydraulic impact machines such as breakers,
There is a one-to-one correspondence between the amplitude of the hydraulic piston and the striking force, and during kissing work, the striking force can be easily adjusted just by operating the handle.

[Brief explanation of drawings]

The drawings show an embodiment of a variable amplitude hydraulic oscillator equipped with the amplitude control device of the present invention, and FIG. FIG. 2 is a vertical cross-sectional view showing a state in which the valve is in operation, and FIG. 2 is a vertical cross-sectional view showing a state in which the amplitude is adjusted to the maximum and a constant pressure is applied to the spool of the pilot valve and the hydraulic piston. 1... Variable amplitude hydraulic oscillator, 2... Pilot valve, 3... Cylinder, 4... Hydraulic piston, 5...
...Variable valve, 6...Remote control valve, 7...Spool,
8... Supply/discharge chamber, 9... Small diameter operating rod, 10... Large diameter operating rod, 11... Constant pressure chamber, 12... Alternating pressure chamber, 13... Oil supply hole, 14... Communication hole, 15... …
Oil drain hole, 16... Fixed liner, 17... Sliding liner, 18... Small diameter part, 19... Spool part, 20
... Small diameter part, 21 ... Constant pressure chamber, 22 ... Alternating pressure chamber, 23 ... Communication chamber, 24, 25 ... Brake chamber, 26, 27 ... Brake step section, 28 ... Oil chamber, 29 ...Fuel filler port, 30...Oil drain port, 31...
Communication port, 32...Communication port, 33...Refueling port, 34
... Spool, 35 ... Supply and discharge chamber, 36 ... Small diameter operating rod, 37 ... Large diameter operating rod, 38 ... Constant pressure chamber,
39...Adjustment pressure chamber, 40...Check valve, 41...
Oil supply hole, 42...Communication hole, 43...Oil drain hole, 44
... Cylinder, 45 ... Piston, 46 ... Handle, 47 ... Oil chamber, 48 ... Oil supply pipe connection port, 4
9...Drain oil pipe connection port, 50...Variable valve operation pipe connection port, 51...Supply oil path, 52...Drain oil path, 53
...Oil passage for piston operation, 54...Oil passage for spool operation, 55...Oil passage for sliding liner operation, 56...
...Oil passage for variable valve operation.

Claims (1)

[Claims] 1. Consisting of a pilot valve, a cylinder, a hydraulic piston, a variable valve, and a remote control valve, the pilot valve includes a spool, a small diameter operating rod and a large diameter operating rod that press both ends of the spool, and a constant pressure chamber that operates the small diameter operating rod. The cylinder has a fixed liner, a sliding liner, and a locking nut for adjusting the sliding distance of the sliding liner,
A step between a large diameter part and a small diameter part is provided on the inner surface of both liners, and the common large diameter part of both liners is faced and slidably engaged with the large diameter part of the central part of the hydraulic piston. A constant pressure chamber with a small pressure receiving area is formed between the steps of the hydraulic piston, and an alternating pressure chamber with a large pressure receiving area is formed between the steps of the sliding liner and the hydraulic piston. Equipped with an oil drain port that communicates with the passage, and a communication port that communicates with the alternating pressure chamber of the pilot valve,
The sliding liner has an oil supply port that communicates with the oil supply path and a communication port that constantly communicates with the supply/discharge chamber formed by the annular groove of the spool of the pilot valve, and the variable valve is formed between the sliding liner and the locking nut. The oil chamber is equipped with a spool for supplying and discharging oil, and the remote control valve also consists of a cylinder, handle, etc. that operates the spool of the variable valve. When high-pressure oil is supplied from the hydraulic source to the supply oil path, it is released from the oil supply port of the fixed liner. Pressure oil enters the constant pressure chamber and moves the hydraulic piston. When the hydraulic piston moves a predetermined distance, the communication chamber provided in the center of the hydraulic piston communicates the communication port of the fixed liner with the oil supply port of the sliding liner. When pressure oil enters the alternating pressure chamber of the pilot valve through such communication, the spool moves and the supply/discharge chamber of the spool is communicated with the supply oil passage. When pressure oil enters the alternating pressure chamber, the movement of the hydraulic piston is reversed due to the difference in area between the constant pressure chamber and the alternating pressure chamber applied to the hydraulic piston, and when the hydraulic piston moves further and reaches a predetermined distance, the hydraulic pressure changes. A circuit is provided so that the communication chamber of the piston communicates the oil drain port of the fixed liner with the communication port of the sliding liner, and when the pressure oil in the alternating pressure chamber of the pilot valve spool is discharged by this communication, the spool is connected to the supply oil. A circuit is provided so that pressure oil in a constant pressure chamber that is constantly in communication with the passageway moves through a small diameter operating rod, and such movement connects the supply and discharge chamber of the spool to a discharge oil passage that communicates with a tank of a hydraulic power source;
Through this communication, the pressure oil in the alternating pressure chamber of the sliding liner is discharged, the hydraulic piston is reversed again by the pressure oil in the constant pressure chamber of the fixed liner, and the pressure oil is varied by operating the remote control valve. When supplied to the valve, the spool of the variable valve moves, and the pressure oil in the supply oil path passes through the supply/discharge chamber consisting of the check valve and the annular groove of the spool, and enters the oil chamber formed between the sliding liner and the locking nut. A circuit is provided to move the supplied sliding liner,
Furthermore, when the remote control valve is operated to drain the pressure oil from the variable valve, the spool moves in reverse, and a circuit is provided so that the oil in the oil chamber is discharged from the supply and discharge chamber to the discharge oil path. The supply and discharge chamber is the supply oil path,
A variable amplitude hydraulic oscillation characterized in that a sliding liner is provided to maintain the current position in a position where it does not communicate with any of the discharge oil passages, and the stroke of the hydraulic piston is adjusted by movement of the sliding liner. Amplitude control device for machines.