JPH0112963B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a spool that receives constant pressure and alternating pressure from both sides within a pilot valve;
The present invention relates to an improvement in a hydraulic oscillator in which a hydraulic piston is vibrated by interaction with a hydraulic piston which receives constant pressure and alternating pressure from both sides within a cylinder.

The applicant has been conducting research on the hydraulic oscillator for some time and has already filed a patent application for some of the results. (Jitsugan 54-179448
(No. 1) Such conventional hydraulic oscillators have a constant pressure chamber and an alternating pressure chamber that load constant pressure and alternating pressure on the hydraulic piston, and are formed by the spool portion of the hydraulic piston and the cylinder. It was unsuitable for applications requiring an oscillator, such as compacting ballast under rails.

The present invention aims to eliminate the above-mentioned inconvenience and provide a hydraulic oscillator with a short height.

The hydraulic oscillator of the present invention aims to shorten the overall length of the hydraulic oscillator by providing both or either of a constant pressure chamber and an alternating pressure chamber in a hydraulic piston that is slidably engaged with a cylinder. Embodiments of the invention will be described in detail with reference to the drawings.

In Figure 1, the hydraulic oscillator is pilot valve 2.
and a cylinder 3, and a hydraulic piston 4 in the cylinder 3.
It is equipped with 5 is a spool slidably built into the pilot valve 2, and 6 is a supply/discharge chamber consisting of an annular groove formed in the middle of the spool 5. 7 and 8
are a small-diameter operating rod and a large-diameter operating rod that press both ends of the spool 5, respectively. Reference numerals 9 and 10 are constant pressure chambers and alternating pressure chambers that introduce pressure oil into the end faces of the small-diameter operating rod 7 and the large-diameter operating rod 8, respectively. There is an oil supply hole 11 on the side wall where the pilot valve 2 is attached to the cylinder 3.
A communication hole 12 and an oil drain hole 13 are provided, and when the spool 5 is pushed and moved by the small diameter operating rod 7 (lower part in the figure), the communication hole 12 and the oil drain hole 13 are connected through the supply and discharge chamber 6. When the oil supply hole 11 and the communication hole 12 are communicated with each other through the supply and discharge chamber 6, when the spool 5 is pushed by the large-diameter operating rod 8 and moved (upper part in the drawing). A liner 14 is fitted to the cylinder 3, and a hydraulic piston 4 is slidably fitted to the liner 14. The liner 14 has an oil supply port 1 communicating with the supply oil passage 35.
5, a communication port 16 communicating with the alternating pressure chamber 10 of the spool 5, an oil drain port 17 communicating with the discharge oil path 36, and a communication port 18 communicating with the supply/discharge chamber 6 of the spool are provided. Communication chambers 20, 21, 22 made of annular grooves are provided in the spool portion 19 of the hydraulic piston 4,
Communication chamber 20 and oil supply port 15 and communication chamber 22 and communication port 18 are always in communication, and when hydraulic piston 4 moves upward, oil supply port 15 and communication port 16 are communicated through communication chamber 20, and hydraulic piston 4 is moved downward. , the communication port 16 and the oil drain port 17 are brought into communication through the communication chamber 21. A small reaction force rod 25 and a large reaction force rod 26 respectively fixed to both ends of the cylinder 3 are thrust into the hydraulic piston 4 to form a constant pressure chamber 23 of a small area and an alternating pressure chamber 24 of a large area. A communication oil passage 27 communicates the constant pressure chamber 23 with the communication chamber 20, and a communication oil passage 28 communicates the alternating pressure chamber 24 with the communication chamber 22. Brake chambers 29 and 30 are formed at the upper end of the constant pressure chamber 23 and at the lower end of the alternating pressure chamber 24, respectively. Reference numerals 31 and 32 denote brake steps formed on the small reaction force rod 25 and the large reaction force rod 26, which trap oil and generate brake pressure when they enter the brake chambers 29 and 30. The supply oil passage 35 communicates with the hole 9' communicating with the constant pressure chamber 9 of the pilot valve 2, the oil supply hole 11, and the oil supply port 15 of the liner 14. The drain oil passage 36 communicates with the oil drain hole 13 of the pilot valve 2 and the oil drain port 17 of the liner 14.
37 is a piston operating oil passage that communicates the communication hole 12 of the pilot valve 2 with the communication port 18 of the liner 14. 38 is the oil path for operating the spool and pilot valve 2.
The hole 10' leading to the alternating pressure chamber 10 of the liner 14
It communicates with the communication port 16 of. 39 is cylinder 3
33 is an oil supply pipe connection port, 34 is an oil drain pipe connection port, and 40 is a communication hole communicating with the outside air.

To explain the operation, when high pressure oil is supplied from the supply oil line 35, the pressure oil enters the constant pressure chamber 9 of the pilot valve 2, and the spool 5
While pressing down, the constant pressure chamber 2 of the hydraulic piston 4
3 and pushes up the hydraulic piston 4. The oil in the alternating pressure chamber 24 of the hydraulic piston is discharged to the discharge oil passage 36 through the communication chamber 22, the communication hole 12, the supply/discharge chamber of the spool 5, and the oil discharge hole 13. When the hydraulic piston 4 moves a predetermined distance, the communication chamber 20 communicates with the alternating pressure chamber 10 of the pilot valve 2, pushes up the spool 5, and connects the oil supply hole 11 and the communication hole 12 via the supply and discharge chamber 6.
, and supplies pressure oil to the alternating pressure 24 of the hydraulic piston 4. Hydraulic piston 4 has alternating pressure 24
Due to the area difference between the constant pressure chamber 23 and the constant pressure chamber 23, it reverses and descends. When it moves a predetermined distance, the communication chamber 21 communicates the communication port 16 with the oil drain port 17 to discharge the pressure in the alternating pressure chamber 10 of the pilot valve 2, and the spool 5 is pushed down by the pressure oil in the constant pressure chamber 9. Since the communication hole 12 and the oil drain hole 13 are communicated with each other via the supply/discharge chamber 6, the hydraulic piston 4 reverses again and rises, and the same vibration is repeated thereafter.

Comparing the present invention with the oscillator of the previous application (Utility Application No. 179448/1982), in which a constant pressure chamber and an alternating pressure chamber were formed by combining the steps provided on the inner surface of the cylinder and the outer surface of the hydraulic piston, Since the small diameter portion forming the step of the hydraulic piston in the prior application is housed within the piston, there is an advantage that the overall length of the oscillator can be significantly shortened.

The hydraulic oscillator 1A shown in FIG. 2 has a constant pressure chamber configuration different from that of the hydraulic oscillator 1 shown in FIG. 23A, and shows an example in which the extension portion 41 of the hydraulic piston 4A is used for vibration operation. The operation is similar to that shown in FIG.

The hydraulic oscillator 1B of FIG. 3 is different from that of FIG. 2 in that the supply/discharge chamber 6 of the spool 5 and the alternating pressure chamber 24 are communicated via a communication oil passage 28B provided in the large reaction force rod 26B, and the hydraulic oscillator 1B of FIG. 4B and the large reaction force rod 26B is made to communicate with the discharge oil passage 36, and is further shortened than that shown in FIG. 2. The only difference in operation from Figures 1 and 2 is that the pressure oil in the supply oil passage 35 is at a constant pressure of 2.
3A, the hydraulic piston 4B rises, and when the constant pressure chamber 23A and the communication port 16 communicate with each other, the spool 5
rises, and the pressure oil in the supply oil passage 35 passes from the supply/discharge chamber 6 of the spool 5 to the alternating pressure chamber 2 through the communication oil passage 28B.
Enter 4. The hydraulic piston 4B reverses and descends,
When the communication port 16 and the communication chamber 21B communicate with each other, the pressure oil in the alternating pressure chamber 10 of the pilot valve 2 is drained, so the spool 5 is lowered, and the pressure oil in the alternating pressure chamber 24 of the hydraulic piston 4B is drained from the communication hole 12 and drained. Since the oil is discharged through the oil hole 13, the hydraulic piston 4B reverses itself again and rises.

The difference between the hydraulic oscillator 1C in FIG. 4 and that in FIG. 1 is that the small diameter part provided above the liner 14C and the small diameter part provided in the hydraulic piston 4C are mated together to form an alternating pressure chamber 24C. Operation is the first
It is the same as shown in the figure.

Although the differences between FIGS. 1 to 4 are largely the same, it is best to use the most optimal form depending on the intended use of the oscillator, and they specifically show possible structural examples.

[Brief explanation of drawings]

The figures show an embodiment of the hydraulic oscillator of the present invention, in which Fig. 1 is a longitudinal sectional view when both a constant pressure chamber and an alternating pressure chamber are formed inside a hydraulic piston, Fig. 2, and Fig. FIG. 3 shows an embodiment in which only alternating pressure chambers are formed, and FIG. 4 shows an embodiment in which only constant pressure chambers are formed. 1...Hydraulic oscillator, 2...Pilot valve, 3...
... Cylinder, 4 ... Hydraulic piston, 5 ... Spool, 6 ... Supply and discharge chamber, 7 ... Small diameter operating rod, 8 ... Large diameter operating rod, 9 ... Constant pressure chamber, 10 ... Alternating pressure chamber, 11...Oil supply hole, 12...Communication hole, 13...
Oil drain hole, 14...liner, 15...oil filler port, 16
... Communication port, 17 ... Oil drain port, 18 ... Communication port,
19... Spool part, 20, 21, 22... Communication chamber, 23... Constant pressure chamber, 24... Alternate pressure chamber, 2
5...Small reaction force rod, 26...Large reaction force rod, 27, 28
...Communication oil passage, 29,30...Brake chamber, 3
1, 32... Brake step, 33... Oil supply pipe connection port, 34... Oil drain pipe connection port, 35... Oil supply path, 36... Discharge oil path, 37... Oil path for piston operation, 38 ... Oil passage for spool operation, 39 ... Side plate, 40 ... Communication hole, 41 ... Extension part.

Claims (1)

[Claims] 1. Interaction between a spool that receives constant pressure and alternating pressure from both sides in a pilot valve and a hydraulic piston that receives constant pressure and alternating pressure from both sides in a cylinder. Therefore, in a hydraulic oscillator in which the hydraulic piston is made to vibrate, a small reaction force rod and a large reaction force rod fixed to both ends of the cylinder are inserted into the hydraulic piston that is slidably engaged with the cylinder. A constant pressure chamber with a small area and an alternating pressure chamber with a large area are configured, and the constant pressure chamber is always in communication with the oil supply pipe from the side of the hydraulic piston, and the alternating pressure chamber is always in communication with the supply and discharge chamber formed by the annular groove of the spool. A communication chamber is provided in the hydraulic piston so that when the hydraulic piston moves a predetermined distance by the pressure oil in the constant pressure chamber, the alternating pressure chamber of the spool communicates with the oil supply pipe, and the spool moves by the alternating pressure. A circuit is provided to communicate the supply and discharge chamber of the spool with the oil supply pipe so that pressure oil is supplied to the alternating pressure chamber of the hydraulic piston when the hydraulic piston moves, and when the hydraulic piston moves a predetermined distance, the spool's A communication chamber is provided in the hydraulic piston so that the alternating pressure chamber communicates with the discharge path, and when the alternating pressure applied to the spool is released and the spool moves due to constant pressure, the circuit is established so that the supply and discharge chamber of the spool communicates with the discharge circuit. When the pressure oil in the alternating pressure chamber of the hydraulic piston provided and constantly communicating with the supply/discharge chamber is released, the hydraulic piston reverses its motion again.
A shortened hydraulic oscillator characterized in that it vibrates such a hydraulic piston. 2. The hydraulic piston is activated by the interaction between the spool, which receives constant pressure and alternating pressure from both sides in the pilot valve, and the hydraulic piston, which receives constant pressure and alternating pressure from both sides in the cylinder. In a hydraulic oscillator designed to vibrate, a reaction rod fixed to one end of a cylinder is inserted into a hydraulic piston slidably engaged with the cylinder to form a constant pressure chamber or an alternating pressure chamber, and the cylinder An oil chamber formed by a step provided on the inner surface of the hydraulic piston and an outer surface of the hydraulic piston is configured as an alternating pressure chamber corresponding to a constant pressure chamber within the hydraulic piston, or a constant pressure chamber corresponding to an alternating pressure chamber within the hydraulic piston, The constant pressure chamber is always in communication with the oil supply pipe,
A circuit is provided so that the alternating pressure chamber is in constant communication with the supply/discharge chamber formed by the annular groove of the spool, and when the hydraulic piston moves a predetermined distance by the pressure oil in the constant pressure chamber, the alternating pressure chamber of the spool communicates with the oil supply pipe. A circuit is provided to connect the supply/discharge chamber of the spool with the oil supply pipe so that when the spool is moved by alternating pressure, pressure oil is supplied to the alternating pressure chamber of the hydraulic piston. As a result, when the motion is reversed and the spool moves a predetermined distance, a circuit is established to communicate the alternating pressure chamber of the spool with the discharge circuit, and the alternating pressure applied to the spool is released.
When the spool moves due to constant pressure, a circuit is provided so that the supply and discharge chamber of the spool communicates with the discharge oil passage, and when the pressure oil in the alternating pressure chamber of the hydraulic piston, which is always in communication with the supply and discharge chamber, is released, the hydraulic piston is a shortened hydraulic oscillator, characterized in that it reverses its motion again and causes the vibration of the hydraulic piston to take place.