JPS5822643B2 - Vibration control device in hydraulic oscillators - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration control device for a hydraulic oscillator.

Hydraulic oscillators that vibrate hydraulic screws through interaction between a spool in a pilot valve and a hydraulic piston in a cylinder have been used in various working machines.

However, hydraulic oscillators used in various types of work machines are designed to have vibration characteristics suitable for each work purpose. (see Figure 7), and in the case of rock drilling, the oil supply hole and oil drain hole of the pilot valve should be pre-diagnosed so that the forward movement time of the hydraulic piston is shorter than the return movement time (see Figure 6). Because of the hole size design, the hydraulic oscillators utilized in these single-purpose work machines cannot have their vibration characteristics adjusted for other applications.

On the other hand, when performing fatigue tests on materials using a hydraulic oscillator, different vibration characteristics are required for different load conditions.

The object of the present invention is to provide a vibration control device for a hydraulic oscillator that has a simple structure and can easily adjust and change the vibration characteristics, and in which stoppers are provided at both ends of the pilot valve 0 and moved back and forth so as to face both end faces of the spool. A small-diameter operating rod and a large-diameter operating rod are built into a small-diameter hydraulic chamber and a large-diameter hydraulic chamber formed in each of the stoppers so as to move in and out from the inner end surface of the stopper to press the spool. This is characterized in that the forward or backward movement of the hydraulic piston is delayed by narrowing the opening degree of the oil supply hole or oil drain hole of the pilot valve using the spool via the spool.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

1 and 2 are sectional views of a hydraulic oscillator equipped with the vibration control device of the present invention, and FIG. 3 is an enlarged sectional view of a pilot valve.

In FIGS. 1 to 3, reference numeral 1 denotes a hydraulic oscillator, which includes a pilot valve 2, a cylinder 3, and a hydraulic piston 4. As shown in FIG.

6 is a valve chamber in which the spool 5 is slidably housed, and 7 and 8 are a small-diameter operating rod and a large-diameter operating rod that press both ends of the spool 5, respectively.

Numerals 9 and 10 are Bragg-shaped collars 1 disposed opposite to both end surfaces of the spool 5, and are screwed into threaded portions 5 at both ends of the valve chamber 6 so as to be movable forward and backward.

11 and 12 are a small diameter oil chamber and a large diameter oil chamber provided in the stoppers 9 and 10, respectively.

Bolts 13 and 14 are screwed into the openings of the small diameter oil chamber 11 and the large diameter oil chamber 12, respectively.

The small diameter operating rod 7 and the large diameter operating rod 8 are operated by pressure oil introduced into the small diameter oil @ 11 and the large diameter oil chamber 12 through holes 11' and 12' provided at both ends of the side wall of the valve chamber 6. The stoppers 9 and 10 are moved forward and backward by turning the bolts 13 and 14 with a spanner.

An oil supply hole 15, a communication hole 16, and an oil drain hole 17 are provided in the middle of the side wall where the pilot valve 2 is attached to the cylinder 3. When the oil supply hole 15 and the communication hole 1 are moved through the valve chamber 6,
Further, when the spool 5 moves to the left as shown in FIG. 2, the communication hole 16 and the oil drain hole 17 are designed to communicate through the valve chamber 6.

The spool portion of the hydraulic piston 4 is attached to the inner surface 18 of the cylinder 3.
is slidably fitted to the

A liner may be provided to prevent wear between the inner surface of the valve chamber 6 and the inner surface 18 of the cylinder 3.

Spool portion of hydraulic piston 4 and inner surface 18 of cylinder 3
The large hydraulic chamber 19, the communicating oil chamber 20, and the small hydraulic chamber 2 are
1 is formed.

The pressure receiving area of the hydraulic piston 4 in the large hydraulic chamber 19 is designed to be larger than the pressure receiving area of the hydraulic piston 4 in the small hydraulic chamber 21, for example, twice as large.

Oil fill ports 2 are provided at both ends of the inner surface 18 of the cylinder 3, respectively.
2 and a communication port 23 are provided, and a fuel filler port 2 is provided in the middle of the inner surface 18.
4 and an oil drain port 25. When the hydraulic piston 4 moves in one direction, for example, to the right as shown in FIG. , when the hydraulic piston 4 moves to the left as shown in FIG.
5 are designed to communicate.

An oil supply port 26 and an oil drain port 21 are provided on the end face of the cylinder 3.

28 is a supply oil passage, and the oil supply port 26 is connected to the pilot valve 2.
The hole 11' communicating with the small diameter oil chamber 11 and the oil supply hole 15 communicate with the oil supply port 22 of the cylinder 3.

Reference numeral 29 denotes a discharge oil passage, which communicates the oil drain port 27 with the oil drain hole 17 of the pilot valve 2 and the oil drain port 25 of the cylinder 3.

30 is an oil passage for operating screws 1 to 2, and the pilot valve 2
The communication hole 16 of the cylinder 3 communicates with the communication port 23 of the cylinder 3.

31 is an oil passage for operating the spool, and a hole 12' communicating with the large diameter oil chamber 12 of the pilot valve 2 is connected to the oil supply port 2 of the cylinder 3.
It is connected to 4.

32 and 33 are brake chambers formed at both ends of the cylinder 3, which apply brakes to the hydraulic piston 4 when the hydraulic piston 4 approaches the ends of both sides of the cylinder 3 alternately. .

The hydraulic oscillator 1 of the present invention configured as described above can be incorporated into, for example, a material testing machine, and used by connecting the oil supply port 26 and oil drain port 27 of the cylinder 3 to a hydraulic power source and a tank, etc. (not shown), respectively. It is something to do.

Therefore, when pressure oil is supplied from the hydraulic source to the supply oil passage 28 through the oil supply port 26, the pressure oil is introduced into the small diameter oil chamber 11 and the small hydraulic chamber 21 through the hole 11' and the oil supply port 22.

In the pilot valve 2, the spool 5 moves to the left via the small-diameter operating rod 7, and in the cylinder 3, the hydraulic piston 4 starts moving to the right.

At this time, the large hydraulic chamber 19 includes the communication port 23, the piston operating oil passage 30, the communication hole 16, the valve chamber 6, the oil drain hole 17, and the discharge oil passage 2.
9 and an oil drain port 27 to a tank (not shown).

Next, as shown in FIG. 1, during the movement of the hydraulic piston 4 to the right, when the oil filler port 24 communicates with the small hydraulic chamber 21, the pressure oil in the small hydraulic chamber 21 is transferred from the oil filler port 24 for spool operation. The oil is introduced into the large diameter oil chamber 12 of the pilot valve 2 through the oil passage 31 and the hole 12'.

Since the pressure receiving area of the large diameter working rod 8 is larger than the pressure receiving area of the small diameter working rod 7, the large diameter working rod 8 overcomes the pressing force of the small diameter working rod 7 and moves the spool 5 to the right.

(See Figure 1). When the spool 5 moves to the right, the valve chamber 6
The oil supply hole 15 and the communication hole 16 communicate with each other through the oil supply hole 15, the valve chamber 6, the communication hole 16, and the piston operating oil passage 3.
0 and is introduced into the large hydraulic chamber 19 through the communication port 23.

Since the pressure receiving area of the hydraulic piston 4 in the large hydraulic chamber 19 is larger than the pressure receiving area of the hydraulic piston 4 in the small hydraulic chamber 21, the hydraulic piston 4 starts moving to the left.

Next, as shown in FIG. 2, when the oil supply port 24 and the oil drain port 25 communicate with each other via the communication oil chamber 20 during the movement of the hydraulic piston 4 to the left, the pressure oil in the large diameter oil chamber 12 is released. is led out to a tank (not shown) through the hole 12', the spool operating oil passage 31, the oil filler port 24, the communicating oil chamber 20, the oil drain port 25, the drain oil path 29, and the oil drain port 27, and the large diameter oil chamber 12 As the internal pressure decreases, the spool 5 is pressed by the small diameter operating rod 7 and moves to the left.

When the spool 5 moves to the left, the communication hole 16 opens into the valve chamber 6.
The pressure oil in the large hydraulic chamber 19 is communicated with the oil drain hole 17 through the communication port 23, the piston operating oil passage 30, the communication hole 16,
The oil is led out to a tank (not shown) through the valve chamber 6, drain hole 17, drain oil passage 29, and oil drain port 27, and the pressure in the large hydraulic chamber 19 decreases, so the hydraulic piston 4 moves into the small hydraulic chamber 21. Pressed by the pressure oil, it moves to the right and returns to the state shown in FIG. 1, and the above operation is repeated thereafter.

As can be easily understood from the above explanation, the large hydraulic chamber 1
When the hydraulic piston 4 moves forward to the left due to the pressure oil in the small hydraulic chamber 21, an impact force is generated, and the pressure oil in the small hydraulic chamber 21 causes the hydraulic piston 4 to move back to the right.

As described above, the hydraulic piston 4 can be vibrated by the interaction between the spool 5 in the pilot valve 2 and the hydraulic piston 4 in the cylinder 3.

1 and 2 show a state in which the stoppers 9 and 10 are fixed at their reference positions, respectively, and the oil supply hole 15 and the oil drain hole 17 are not constricted by the spool 5.

The pressure receiving area of the hydraulic piston 4 in the large hydraulic chamber 19 is
For example, if the area of the hydraulic piston 4 in the small hydraulic chamber 21 is designed to be twice as large as the pressure receiving area, the vibration of the hydraulic piston 4 will continue for a forward movement time t as shown in FIG.

and the backward movement time to' become equal.

Therefore, when the stopper 10 is screwed in through the bolt 14, when the spool 5 moves to the left as shown in FIG. is narrowed down.

As a result, the pressure oil in the large hydraulic chamber 19 is transferred to the communication port 2.
3. The oil is discharged to a tank (not shown) through the piston operating oil passage 30, the communication hole 16, the valve chamber 6, the oil drain hole 17, the oil discharge passage 29, and the oil drain port 27, and when the hydraulic piston 4 is moved back. The discharge of pressure oil is restricted at the oil drain hole 17, and the vibration of the hydraulic piston 4 is delayed in the backward movement time tLl compared to the forward movement time 'L, as shown in FIG.

Next, when the stopper 9 is screwed in through the bolt 13 in the opposite manner to the above, the opening degree of the oil supply hole 15 is narrowed by the spool 5 when the spool moves to the right as shown in FIG.

This allows pressure oil to be transferred from the hydraulic source outside the area to the oil filler port 2.
6, oil supply path 28, oil supply hole 15, valve chamber 6, communication hole 16,
The pressure oil is introduced into the large hydraulic chamber 19 through the piston operating oil passage 30 and the communication port 23, and when the hydraulic piston 4 moves forward, the introduction of pressure oil is restricted at the oil supply hole 15, and the vibration of the hydraulic piston 4 is reduced. As shown in FIG. 7, the forward movement time tB is delayed compared to the backward movement time iR,1.

As described above, the oil supply hole 15 or the oil drain hole 1 of the pilot valve 2 is
By narrowing down the opening degree of the hydraulic piston 4, the forward or backward movement of the hydraulic piston 4 can be delayed.

The stoppers 9 and 10 are screwed into screw portions at both ends of the valve chamber 6 so as to be able to move forward and backward, and a small diameter oil chamber 12 is formed in the stoppers 9 and 10.
Since the small-diameter operating rod 7 and the large-diameter operating rod 8 are slidably built into each of the two, only the stopper 9 or 10 can be screwed in without pressing the small-diameter operating rod 7 and the large-diameter operating rod 8. , the opening of the oil supply hole 15 or the oil drain hole 17 can be continuously and minutely adjusted.

Pressure oil is supplied from the cylinder 3 to the large diameter oil chamber 12 of the pilot valve 2 via the oil supply port 24, the spool operating oil passage 31, and the hole 12'.
Since the hydraulic piston 4 vibrates stably by forcibly switching the spool 5 by feeding back to the spool 5, both the frequency and waveform of the hydraulic piston 4 become stable.

As can be easily understood from the above explanation, when using the vibration control device for the hydraulic oscillator of the present invention, the forward or backward movement of the hydraulic piston can be delayed by adjusting the stopper that can be moved forward or backward from the outside of the pilot valve. Therefore, it is suitable for material testing machines that require different types of vibration characteristics.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIGS. 1 and 2 are vertical cross-sectional views showing the backward movement state and forward movement state of the hydraulic piston, respectively, and FIG. 3 is an enlarged vertical cross-sectional view of the pilot valve. , Figure 4 is a sectional view of the main part showing the throttled state of the oil drain hole, and Figures 5 to 7 are the hydraulic pistons without throttle, with the oil drain hole throttled, and with the oil supply hole throttled, respectively. It is a vibration curve diagram of. 1: Hydraulic oscillator, 2: Pilot valve, 3 Niji cylinder, 4
: Hydraulic piston, 5 varnish spool, 6: Valve chamber, 7: Small diameter operating rod, 8: Large diameter operating rod, 9: Stopper, 10: Stopper, 11: Small diameter oil chamber, 11': Hole, 12: Large diameter oil chamber , 12
Filling hole, 13: Bolt, 14: Bolt, 15: Oil supply hole, 1
6: Communication hole, 17: Oil drain hole, 18: Inside surface, 19: Large hydraulic chamber, 20: Communication oil chamber, 21: Small hydraulic chamber, 22: Oil filler port, 23: Communication port, 24: Oil filler port, 25 :Drain port, 26:
Oil supply port, 27: Oil drain port, 28: Supply oil path, 29: Discharge oil path, 30: Piston operation oil path, 31 Nispuru operation oil path, 32 Ni brake chamber, 33 Ni brake chamber.

Claims (1)

[Claims] 1. The hydraulic piston is vibrated by the interaction between a spool that receives constant pressure and alternating pressure from both sides in the pilot valve and a hydraulic piston that receives constant pressure and alternating pressure from both sides in the cylinder. In this hydraulic oscillator, stoppers are disposed at both ends of the pilot valve so as to be movable toward and away from both end faces of the spool, and a small-diameter operating rod and a small-diameter hydraulic chamber are formed in each of the stoppers. A large-diameter operating rod is built in so as to move in and out from the inner end surface of the stopper and press the spool, and by narrowing the opening of the oil supply hole or oil drain hole of the pilot valve with the spool through the stopper, the hydraulic piston is A vibration control device for a hydraulic oscillator, characterized in that forward movement or backward movement is delayed.