JPH0821406A - Vibrate generating fluid switching valve and oscillation generating device using the same - Google Patents

Abstract

PURPOSE:To obtain strong vibrations by moving a piston of an oscillation generating actuator with high speed in a simple structure. CONSTITUTION:Axial length of each of first introduction, first intake/exhaust, second outlet, second intake/exhaust ports 58, 23, 61, 26 exceeds circumferential length thereof. Communication shapes between the ports 58 with 23, and between the ports 61 with 26 show long and narrow forms in an axial direction, and areas wider than conventional ones from the starting of the communication. Pressure in a cylinder divided chamber 78a is abruptly increased, and pressure reduction in the ports are minimized for enlarging pressure difference between the cylinder divided chambers 78a and b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration generating fluid switching valve and a vibration generating device using the fluid switching valve.

[0002]

2. Description of the Related Art Generally, a vibration generator is used for civil engineering construction work,
For example, it is used when excavating earth and sand, crushing concrete, stones, etc., and flattening the ground.As a fluid switching valve used for such a vibration generator, the present applicant has filed Japanese Patent Application No. Hei 5-21659. I have proposed as described in the issue.

This is a casing in which a valve chamber is formed, a rotary valve body rotatably housed in the valve chamber, and a rotating means for applying a rotational force to the rotary valve body to rotate it about its axis. And a supply / discharge passage provided in the casing and having one end open to the valve chamber, a circular first supply / discharge port formed in an end surface of the valve chamber, and provided in the casing, and one end of the first A first supply / discharge passage connected to the first supply / discharge port, a circular second supply / discharge port formed on the end face of the valve chamber circumferentially separated from the first supply / discharge port, and provided in the casing, A second one end of which is connected to the second supply / discharge port
The supply / discharge passage, a circular introduction and discharge port alternately formed at a position on the end face of the rotary valve body that can overlap the first and second supply / discharge ports, and the rotary valve body are provided with one end of the supply passage. Is provided in the rotary valve body, the one end of which is always in communication with one end of the discharge passage and the other end of which is connected to the introduction port. A state in which the rotary valve body rotates and the first and second supply / discharge ports communicate with the introduction / discharge port, respectively, and the first and second supply / discharge ports, and The high pressure fluid from the supply passage is alternately supplied to the first and second supply / discharge passages by repeatedly switching to a state in which the introduction port and the introduction port are in communication with each other.

[0004]

Although such a fluid switching valve for generating vibration can be sufficiently put into practical use, it has a stronger vibration in order to improve the efficiency of civil engineering construction work. There has been a demand for a fluid switching valve capable of generating (impact force), and various proposals have been made for this reason. However, none of them have a simple structure and can sufficiently enhance vibration.

[0005]

For this reason, the present inventor has conducted earnest research and obtained the following findings. That is, introduction,
When the outlet port and the first and second supply / discharge ports are both circular, the opening shape in which these ports communicate with each other at the initial stage of introduction and when the first supply / discharge ports start communicating with each other Since the convex lens shape is extremely narrow, the amount of fluid flowing through such a narrow opening is small, that is, the amount of fluid supplied to the head side cylinder chamber of the vibration generating actuator is also small. The rise in pressure in the head-side cylinder branch chamber is somewhat gradual, and the protrusion speed of the piston becomes slow (vibration, impact force weakened). Further, at the initial stage of the communication start as described above, since the communication areas of the introduction, the first supply / discharge ports and the lead-out, and the second supply / discharge ports are extremely small as described above, these ports function as throttles. As a result, a pressure drop is caused in the passing fluid, which lowers the pressure in the head side cylinder sub-chamber of the vibration generating actuator and increases the back pressure in the rod side cylinder sub-chamber. As a result, the pressure difference between the two cylinder chambers becomes smaller, and the protrusion speed of the piston becomes even slower.

The present invention has been made based on such knowledge, and has a casing having a valve chamber formed therein, a rotary valve body rotatably housed in the valve chamber, and a rotary force applied to the rotary valve body. Means for rotating around an axis by providing a supply / discharge passage provided in the casing with one end opening to the valve chamber, and a first supply / discharge port formed on the inner peripheral surface of the valve chamber. A first supply / discharge passage provided in the casing, one end of which is connected to the first supply / discharge port, and a second formed on the inner peripheral surface of the valve chamber axially separated from the first supply / discharge port. The supply / discharge port is provided in the casing, and one end is the second
A second supply / discharge passage connected to the supply / discharge port, and first introductions formed on the outer circumference of the rotary valve body at the same axial position as the first supply / discharge port and arranged alternately in the circumferential direction; The outlet port, the second inlet and outlet ports formed on the outer circumference of the rotary valve body at the same axial position as the second supply / discharge port and alternately arranged in the circumferential direction, and provided on the rotary valve body, An introduction passage having one end always communicating with one end of the supply passage and the other end connected to both the first and second introduction ports;
A rotary valve body, one end of which is always in communication with one end of the discharge passage, and the other end of which is connected to both the first and second discharge ports, and the rotary valve body rotates, First,
A state in which the second supply / discharge port and the first introduction / second derivation port communicate with each other, and a state in which the first and second supply / discharge ports communicate with the first derivation / second introduction port, respectively. In the vibration generating fluid switching valve, the high pressure fluid from the supply passage is alternately supplied to the first and second supply / discharge passages by repeatedly switching to the first and second supply / discharge ports and the first and second supply / discharge ports. The length in the axial direction of the introduction / second discharge port is larger than the length in the circumferential direction.

[0007]

Now, it is assumed that the high-pressure fluid in the supply passage is supplied to the first and second introduction ports through the introduction passage. In this state, the rotary valve body is rotated by the rotating means, and the communication between the first introduction port and the first supply / discharge port starts, and the communication between the second outlet port and the second supply / discharge port starts. The high-pressure fluid is supplied from the first introduction port to the first supply / discharge passage through the first supply / discharge port, and is guided to, for example, the head side cylinder compartment of the vibration generating actuator. At this time, the return fluid flowing out from the rod side cylinder compartment is discharged through the second supply / discharge passage, the second supply / discharge port, the second outlet port, and the outlet passage. Here, focusing on the initial stage of the above-mentioned communication, when the axial length of the first introduction, first supply / discharge, second derivation, and second supply / discharge ports is larger than the circumferential length as in the present invention. In addition, since the opening shape in which the first introduction and the first supply / discharge ports communicate with each other from the initial stage of the communication is elongated in the axial direction and the area becomes wider than the conventional one,
The amount of fluid supplied to the head side cylinder branch chamber of the vibration generating actuator increases, and as a result, the pressure in the cylinder branch chamber abruptly increases and the piston moves at a high speed toward the forward movement side (projection side) (vibration). , The impact will be stronger). Further, in the present invention, similarly to the above, the first introduction, the first supply / discharge ports and the second derivation from the initial stage of the communication start,
Since the communication area between the second supply / discharge ports is wider than before, the fluid passes through these ports with little pressure drop and is supplied to the head side cylinder branch chamber and discharged from the rod side cylinder branch chamber. The pressure in the head-side cylinder sub-chamber substantially increases to the set pressure, and the rod-side cylinder sub-chamber also substantially decreases to, for example, the tank pressure. As a result, the pressure difference between the two cylinder chambers becomes large, and the piston moves to the forward movement side (projection side) at a higher speed (vibration and impact force become stronger). Then, when the rotary valve body further rotates to start the communication between the first outlet port and the first supply / discharge port and the communication between the second introduction port and the second supply / discharge port, the second The high-pressure fluid is guided from the introduction port to the rod-side cylinder branch chamber of the vibration generating actuator, and the piston moves to the return side (retraction side). When the rotary valve body rotates in this manner, the first supply / discharge port, the second supply / discharge port and the first introduction / second discharge port are in communication with each other, and the first supply / discharge port and the second supply / discharge port are connected. It is repeatedly switched to a state in which the first lead-out port and the second lead-in port are in communication with each other, whereby the piston reciprocates in the cylinder chamber to generate vibration.

According to the second aspect of the invention, the communication area between the first lead-out, the first supply / discharge ports and the second introduction, and the second supply / discharge ports is wider than in the conventional case from the beginning of the communication. Therefore, the piston of the vibration generating actuator can move at high speed to the returning side (retracting side) (vibration becomes strong). Further, according to the third aspect, it is possible to appropriately control the pressure and the flow rate of the high-pressure fluid supplied to the cylinder compartment by the pressure and the flow rate control valve, and thus the moving speed of the piston and the reciprocating time. (Vibration intensity, frequency) can be adjusted according to the civil engineering construction work.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 1, 2, 3, 4, and 5, reference numeral 11 denotes a case, and an upper end of the case 11 has a storage hole with an open upper end.
12 is formed, and the upper end opening of the storage hole 12 is closed by a cover 13 attached to the case 11. A sleeve 14 is housed and fixed in the closed housing hole 12, and a valve chamber 15 having a circular cross section is formed inside the sleeve 14 so as to extend in the axial direction (vertical direction). The case 11, the cover 13, and the sleeve 14 described above as a whole include the casing 16
Is configured.

A rotary valve body 18 capable of rotating around an axis is housed in the valve chamber 15, and a rotating means mounted on the casing 16 is provided in the valve chamber 15 above the rotary valve body 18. The fluid motor 19 as described above, for example, a known trochoid hydraulic motor is housed. The lower end of the output shaft 20 of the fluid motor 19 is inserted into the upper portion of the rotary valve body 18 and spline-coupled. As a result, when the fluid motor 19 is activated, the rotary valve body 18 is
It is given a rotational force from 19 and rotates about its axis. In addition,
21 is between the rotary valve body 18 and the fluid motor 19 and the rotary valve body 18
And thrust bushes that are respectively interposed between and the bottom of the storage hole 12.

A plurality of first supply / discharge ports 23 are formed on the inner peripheral surface of the valve chamber 15 (sleeve 14) equidistantly in the circumferential direction, and the outer peripheral surfaces of the first supply / discharge ports 23 and the sleeve 14 are formed. It is connected to the first annular groove 24 formed by a plurality of first radial passages 25 extending in the radial direction. Also, the first
A plurality of second supply / discharge ports 26, which are equidistant in the circumferential direction, are formed on the inner peripheral surface of the valve chamber 15 axially (downwardly) spaced a predetermined distance from the supply / discharge port 23. The port 26 and the second annular groove 27 formed on the outer peripheral surface of the sleeve 14 are connected by a plurality of second radial passages 28 extending in the radial direction. The first and second supply / discharge ports 23, 26 have an axial length larger than the circumferential length, and are formed in a slender rectangular shape in the axial direction, and their circumferential positions are the same ( Same phase). A plurality of supply ports 29 equidistant in the circumferential direction are formed on the inner peripheral surface of the valve chamber 15 between the first and second supply / discharge ports 23, 26.
29 and the supply annular groove 31 formed on the outer peripheral surface of the sleeve 14 are connected by a plurality of supply radial passages 30 extending in the radial direction.

Reference numerals 34 and 35 are first and second fluid passages formed in the case 11. One end of the first fluid passage 34 is always in communication with the supply annular groove 31, and the second fluid passage 35 has an end. One end is connected to the fluid motor 19 via a connection passage 36 formed in the sleeve 14.
It is connected to the. And these first and second fluid passages
The other ends of 34 and 35 are connected to one end of the third fluid passage 37 while merging. 38 is a fluid pump as a fluid source,
The fluid pump 38 and the tank 39 as a discharge source are connected by a suction passage 40. High and low pressure passages 41, 42 are formed in the case 11, and the high pressure passage 41 and the fluid pump 38 are connected by a discharge passage 43, while the low pressure passage 42 and the tank 39 are connected by a return passage 44. There is. Reference numeral 45 denotes a first low pressure fluid which is formed in the casing 16 and discharges the low pressure fluid discharged from the fluid motor 19 to the outside of the casing 16.
A discharge passage, 46 is a second discharge passage for returning the low-pressure fluid flowing out from the first discharge passage 45 to the tank 39.

A switching valve 48 provided in the case 11 is provided between the high pressure and low pressure passages 41 and 42 and the other end of the third fluid passage 37, that is, in the middle of a supply passage 53 described later. ,
The switching valve 48 has a spool 50 slidably accommodated in a spool chamber 49. And this switching valve 48 is a spool
By moving 50 in the spool chamber 49 in the axial direction, high pressure,
The third fluid passages 41 and 37 communicate with each other and the low pressure passage
An open position that shuts off the high pressure / low pressure passages 41, 42 and a closed position that shuts off the third fluid passage 37.
Switch to. A central portion of a lever 52 having a base end rotatably connected to the case 11 is connected to an upper end of the spool 50 protruding upward from the case 11, and as a result, the lever 52 is centered on the base end. As it is swung upward, the switching valve 48 switches from the open position to the closed position. The high pressure passage 41, the third, first and second fluid passages 37, 34 and 35, the supply annular groove 31, the supply radius passage 30, and the supply port 29 are provided in the casing 16 as a whole, and one end thereof is a valve chamber. A supply passage 53 having an opening at 15 and the other end opening at the outer surface of the casing 16 is formed. The pressure of the high-pressure fluid flowing through the supply passage 53 is reduced by the pressure reducing valve 54 as a pressure control valve that is interposed in the discharge passage 43, and the flow rate of the high-pressure fluid flowing through the supply passage 53 is The flow rate is controlled by a variable flow rate control valve 55 provided in the middle of the second fluid passage 35.

Reference numerals 58 and 59 denote a plurality of first introduction and first introduction ports formed on the outer circumference of the rotary valve body 18 at the same axial position as the first supply / discharge port 23. Since the first outlet ports 58 and 59 are alternately arranged in the circumferential direction,
When the rotary valve body 18 rotates, it communicates with the first supply / discharge port 23 alternately. Further, reference numerals 60 and 61 denote a plurality of second outer peripheral portions of the rotary valve body 18 formed at the same axial position as the second supply / discharge port 26.
Introduced, second derived port, these are the second introduced, second
Since the outlet ports 60 and 61 are alternately arranged in the circumferential direction, when the rotary valve body 18 rotates, the outlet ports 60 and 61 communicate with the second supply / discharge port 26 alternately. Where these first introduction and first derivation ports
58, 59 and the second inlet / outlet ports 60, 61 are the openings of the rotary valve body 18 in the opening formed on the outer periphery of the rotary valve body 18.
Is a portion that can overlap the first supply / discharge port 23 and the second supply / discharge port 26 by the rotation of. Further, in this embodiment, the first introduction port, the first derivation port 58, 59, the second introduction port, and the second derivation port 60, 61 are also the first and second supply / discharge ports 23,
Similar to 26, the length in the axial direction is larger than the length in the circumferential direction, and here, the rectangular shape is elongated in the axial direction.

First introduction, derivation ports 58, 59 and second introduction,
A supply annular groove 64 continuously extending in the circumferential direction is formed at a position facing the supply port 29 on the outer circumference of the rotary valve body 18 between the outlet ports 60 and 61, and the supply annular groove 64 is provided with the supply. The high-pressure fluid is constantly supplied through the passage 53. On the outer periphery of the rotary valve body 18 on both sides of the supply annular groove 64 in the axial direction, a plurality of first and second axially extending first and second introduction ports 58 and 60 from the supply annular groove 64 are provided. 2 supply groove
65, 66 are formed, and these first and second supply groove 65, 66 are formed.
Are arranged alternately in the circumferential direction. The first and second introduction ports 58 and 60 are connected to the tip portions of the first and second supply concave grooves 65 and 66, respectively. The supply annular groove 64, the first and second supply concave grooves 65, 66 described above are
An introduction passage 67 is provided in the rotary valve body 18, one end of which is always in communication with one end of the supply passage 53, and the other end of which is connected to both the first and second introduction ports 58 and 60.

Reference numeral 68 denotes a plurality of first discharge concave grooves formed on the outer periphery of the rotary valve body 18, and these first discharge concave grooves 68 are first led out from the upper end of the rotary valve body 18 close to the fluid motor 19. port
It extends axially toward 59 and is arranged at the same circumferential position (in phase) as the second supply groove 66. Reference numeral 69 denotes a plurality of second discharge concave grooves formed on the outer circumference of the rotary valve body 18, and these second discharge concave grooves 69 are provided from the lower end of the rotary valve body 18 close to the bottom surface of the housing hole 12 to the second outlet port 61. It extends in the axial direction toward and is arranged at the same circumferential position (in the same phase) as the first supply groove 65. As a result, these first and second discharge grooves 68, 69 are alternately arranged in the circumferential direction. Then, the first and second outlet ports 59 and 59 are provided at the tips of the first and second discharge grooves 68 and 69.
61 are connected respectively. A discharge hole 70 that opens at the lower end surface of the rotary valve body 18 is formed in the rotary valve body 18, and the discharge hole 70 and the first discharge and second discharge concave grooves 68, 69 are formed in the rotary valve body 18. First radius, second radius passage 71, 72
Connected by and. Reference numeral 73 denotes a discharge passage formed in the case 11, one end of the discharge passage 73 is opened to the bottom surface of the valve chamber 15, and the other end is connected to the tank 39 through the discharge passage 74. The above-mentioned first and second discharge concave grooves 68, 69 and the discharge hole 7
0, the first radius and the second radius passages 71 and 72 are provided in the rotary valve body 18 as a whole, and one end thereof is in constant communication with one end of the discharge passage 73, and the other end thereof is the first and second outlet ports 59, 61 A lead-out passage 75 connected to both sides is formed.

Reference numeral 78 is a casing 16, more specifically, a vertically extending cylinder chamber formed in the case 11. The cylinder chamber 78 has two cylinders formed by a piston 79 slidably accommodated in the cylinder chamber 78. Branch chamber, that is, the first cylinder branch chamber 78a on the head side and the second cylinder branch chamber on the rod side
It is divided into 78b. The first cylinder branch chamber 78a and the first annular groove 24 are formed in the case 11 through the first passage 80 formed in the case 11, and the second cylinder branch chamber 78b and the second annular groove 27 are formed in the case 11. The second passages 81 are connected to each other. The above-described first radius passage 25, first annular groove 24, and first passage 80 are provided in the casing 16 as a whole, one end of which is connected to the first supply / discharge port 23, and the other end of which is the first cylinder branch chamber 78a. First supply / discharge passage connected to
82, and the second radius passage 28, the second annular groove 27, and the second passage 81 are provided in the casing 16 as a whole, one end of which is connected to the second supply / discharge port 26, and the other end of which is provided. A second supply / discharge passage 83 connected to the second cylinder branch chamber 78b is formed. When the rotary valve body 18 is rotated by the fluid motor 19, the first and second supply / discharge ports 23 and 26 and the first introduction,
A state in which the second outlet ports 58 and 61 communicate with each other, and a state in which the first and second supply / discharge ports 23 and 26 communicate with the first outlet and second inlet ports 59 and 60, respectively, The high pressure fluid from the supply passage 53 is alternately supplied to the first and second cylinder branch chambers 78a and 78b through the first and second supply / discharge passages 82 and 83, so that the piston 79 is transferred to the cylinder chamber 78. It reciprocates inside and generates vibration. Here, since the piston rod 84 located in the second cylinder branch chamber 78b is integrally connected to the lower surface of the piston 79, the cross-sectional area of the second cylinder branch chamber 78b (excluding the cross-sectional area of the piston rod 84 is excluded). Value) is smaller than the cross-sectional area of the first cylinder sub-chamber 78a, and as a result, when an equal amount of fluid is alternately supplied to the first and second cylinder sub-chambers 78a and 78b, the piston rod 84 will move with time. It moves (drifts) to the retracted side. Therefore, in this embodiment, the ratio of the cross-sectional area of the first cylinder sub-chamber 78a and the cross-sectional area of the second cylinder sub-chamber 78b is determined by the circumferential lengths of the first introduction and second derivation ports 58, 61 and the first derivation, The ratio is equal to the ratio of the length of the two introduction ports 59, 60 to the circumferential length, so that the first and second cylinder compartments 78a, 78b are alternately supplied with fluid in an amount corresponding to their cross-sectional areas. To prevent the piston 79 from drifting. At this time, the circumferential lengths of the first and second supply / discharge ports 23, 26 are the same. Here, when there is a risk that the piston 79 may drift slightly in the axial direction due to the influence of the load acting on the vibration generating actuator 77, the frictional resistance, etc., the amount of fluid supplied to the first cylinder branch chamber 78a is set to the value described above. It is recommended that the piston 79 be set slightly higher than the value to allow the piston 79 to project. The case 11, the cylinder chamber 78, the piston 79,
The piston rod 84 as a whole constitutes the vibration generating actuator 77 that generates vibration.

The case 11 directly below the piston rod 84 has a tool 8 for civil engineering construction coaxial with the piston rod 84.
5, eg the top of the tilt is replaceably inserted. 8
Reference numeral 6 is a lock pin screwed into the lower end of the case 11 so as to be orthogonal to the tool 85, and the tip of the lock pin 86 is pushed into an annular groove 87 having an arcuate cross section formed in the upper end of the tool 85. The tool 85 is mounted and fixed to the casing 16. As a result, when the piston 79 moves up and down and collides with the tool 85 as described above, the downward moving force of the piston 79 is transmitted to the tool 85 as an impact force, and the tool 85
Vibrate with appropriate vibration force and frequency. At this time, the lock pin 86 prevents the tool 85 from coming out of the case 11. A base end of a handle 88 is fixed to the rear end of the lock pin 86, and a lock nut 89 is screwed to the rear of the lock pin 86. And when changing the tool 85 from tilt to another type, such as chisel tilt, mulberry, scoop, cup, plate for rolling,
After loosening the lock nut 89, turn the handle 88 to retract the lock pin 86, and attach the tip of the lock pin 86 to the annular groove 87.
Evacuate from. Then use the used tool 85 in case 11
After extracting it from the case, use the tool 85 that will be used from now on.
While inserting into 11, the lock pin 86 is rotated to insert its tip into the annular groove 87, and then the lock nut 89 is tightened. Thus, in this embodiment, the lock pin 86
The tool 85 can be easily and easily replaced by rotating the tool. And tools like this
When the type 85 is replaced with another type, the set pressure of the pressure reducing valve 54 and the flow rate control valve 55, and the set flow rate are changed according to the exchanged tool 85. As a result, the moving speed of the piston 79 and the reciprocating time (vibration intensity, vibration frequency) can be adjusted to appropriate values suitable for the tool 85.

Next, the operation of the embodiment of the present invention will be described. For the high pressure fluid discharged from the fluid pump 38, since the switching valve 48 is in the open position, the discharge passage 43, the high pressure passage 41, the third and first fluid passages 37 and 34, the supply annular groove 31, the supply radius passage. 30, supply annular groove 64, first and second supply concave grooves 65, 66
Through the first and second introduction ports 58, 60. In this state, the high pressure fluid is in the second fluid passage.
Since the fluid motor 19 is also supplied through the connection path 35 and the connection passage 36, the fluid motor 19 operates to apply a rotational driving force to the rotary valve body 18 to rotate the rotary valve body 18. And
By such rotation of the rotary valve body 18, the first introduction port 58
Communication with the first supply / discharge port 23 and the second
When the communication between the outlet port 61 and the second supply / discharge port 26 starts, the high pressure fluid is supplied from the first introduction port 58 to the first supply / discharge passage 82 through the first supply / discharge port 23, and thereafter,
This high-pressure fluid is guided to the first cylinder compartment 78a of the vibration generating actuator 77. This causes the piston 79 and the piston rod 84 to move downward (on the protruding side).
The return fluid that has flowed out of the second cylinder branch chamber 78b has a second supply / discharge passage 83, a second supply / discharge port 26, a second outlet port 61, a second discharge concave groove 69, a second radius passage 72, a discharge hole 70, a discharge passage. It is discharged to the tank 39 through 73 and the discharge path 74.

Here, paying attention to the initial stage of the above-mentioned communication, the first introduction and the first supply / discharge port 5 as in this embodiment.
When the axial length of 8 and 23 is larger than the circumferential length, the first introduction, the first supply / discharge port 58, from the initial stage of the communication start,
The opening shape in which the two 23 communicate with each other is elongated in the axial direction and has a larger area than in the conventional case. Therefore, the amount of fluid supplied to the first cylinder chamber 78a of the vibration generating actuator 77 is increased. The pressure in the cylinder compartment 78a rises sharply, and the piston 79 moves at high speed. As a result, the impact force (vibration force) when the tip of the piston rod 84 collides with the tool 85 becomes strong, and the efficiency of civil engineering construction work is improved. Further, in this embodiment, as described above, the first
In addition to the fact that the communication area between the introduction and the first supply / discharge ports 58, 23 is wider than before, the second lead-out, second supply / discharge ports 61, 26
Since the axial length of each of these is also larger than the circumferential length, these second lead-out and second supply / discharge ports 61, 26 are provided from the beginning of the communication.
The shape of the openings communicating with each other is also elongated in the axial direction, and the communication area is wider than before, and as a result, the fluid has almost no pressure drop and these ports 58, 23, 61,
It is supplied to the first cylinder branch chamber 78a through 26 and flows out from the second cylinder branch chamber 78b.
The back pressure generated at 78b is also low. Because of this, the first
The pressure in the cylinder sub-chamber 78a rises substantially to the set pressure, and the pressure in the second cylinder sub-chamber 78b drops substantially to the same pressure as the tank 39, whereby both cylinder sub-chambers 78a, 78
The pressure difference between points b increases and the piston 79 moves at a higher speed. This makes the vibration even stronger.

Then, the rotary valve body 18 further rotates, and the first
When the communication between the outlet port 59 and the first supply / discharge port 23 is started and the communication between the second introduction port 60 and the second supply / discharge port 26 is started, the high pressure fluid vibrates from the second introduction port 60. Second cylinder chamber 78b of generating actuator 77
Is guided to move the piston 79 upward (toward the retracted side), and the return fluid in the first cylinder branch chamber 78a receives the first supply / discharge passage 82, the first supply / discharge port 23, the first discharge port 59,
It is discharged to the tank 39 through the outlet passage 75 and the discharge passage 73. Here, since the axial length of each of the first lead-out / first feed / discharge ports 59, 23 and the second introduction / second feed / discharge ports 60, 26 is larger than the circumferential length, the same as described above. The piston 79 moves to the return side at high speed. When the rotary valve 18 rotates in this way, the first and second supply / discharge ports 23 and 26 and the first introduction,
A state in which the second outlet ports 58 and 61 communicate with each other, and a state in which the first and second supply / discharge ports 23 and 26 communicate with the first outlet and second inlet ports 59 and 60, respectively, It is repeatedly switched to, which causes the piston 79 to move to the cylinder chamber.
The tool 85 reciprocates (vibrates) and an impact force is applied to the tool 85. Then, when the civil construction work by the tool 85 is completed, the lever 52 is swung upward to switch the switching valve 48 to the closed position. As a result, the high-pressure fluid from the fluid pump 38 is directly returned to the tank 39 through the return passage 44 and is not supplied to the fluid motor 19 and the vibration generating actuator 77.

In the above embodiment, the first and second supply / discharge ports 23 and 26, the first and second introduction ports 58 and 60, and the first and second discharge ports 59 and 61 are elongated in the axial direction. Although a rectangular shape is used in the present invention, an oval shape having an axial length larger than the circumferential length, an elliptical shape, or the like may be used. Further, in the present invention, the circumferential lengths of the first introduction port, the second introduction port 58, 60 and the first lead-out port, the second lead-out port 59, 61 are the same as those of the first feed / discharge port 23. Second supply / discharge port 26
So that the ratio of the cross section of the cylinder compartment 78a to the cross section of the cylinder compartment 78b is equal to
As a result, the fluid may be alternately supplied to the cylinder compartments 78a and 78b in an amount corresponding to these cross-sectional areas.
Furthermore, the vibration generator of the present invention may be attached to the arm tip of a power shovel, a bucket, or the like.

[0023]

As described above, according to the present invention, vibration can be sufficiently strengthened with a simple structure.

[Brief description of drawings]

FIG. 1 is a front cross-sectional view, part of which is represented by a symbol, showing an embodiment of the present invention.

2 is a cross-sectional view taken along the line II of FIG.

3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is a sectional view taken along the line II-II of FIG.

5 is a sectional view taken along the line IV-IV in FIG.

[Explanation of symbols]

 15 ... Valve chamber 16 ... Casing 18 ... Rotating valve body 19 ... Rotating means 23 ... First supply / discharge port 26 ... Second supply / discharge port 53 ... Supply passage 54 ... Pressure control valve 55 ... Flow control valve 58 ... First introduction port 59 ... First outlet port 60 ... Second inlet port 61 ... Second outlet port 67 ... Inlet passage 73 ... Discharge passage 75 ... Outlet passage 78 ... Cylinder chamber 78a ... First cylinder branch chamber 78b ... Second cylinder branch chamber 79 ... Piston 82 … First supply / drain passage 83… Second supply / drain passage

Claims (3)

[Claims] 1. A casing 16 having a valve chamber 15 formed therein.
And a rotary valve body 18 rotatably housed in the valve chamber 15,
Rotating means 19 for applying a rotational force to the rotary valve body 18 to rotate it about the axis, and a rotary chamber 19 provided inside the casing 16 and having one end having a valve chamber 15
Supply and discharge passages 53 and 73 that are open to the inside, a first supply and discharge port 23 formed on the inner peripheral surface of the valve chamber 15, and a casing 16 that has one end connected to the first supply and discharge port 23. A connected first supply / discharge passage 82, a second supply / discharge port 26 formed on the inner peripheral surface of the valve chamber 15 axially separated from the first supply / discharge port 23,
The second supply / discharge port is provided in the casing 16 and has one end
The second supply / discharge passages 83 connected to 26 and the first introductions formed on the outer circumference of the rotary valve body 18 at the same axial position as the first supply / discharge ports 23 and arranged alternately in the circumferential direction. Second outlet / inlet ports 60, 61 that are formed at the same axial position as the second supply / discharge port 26 on the outer periphery of the rotary valve body 18 and the outlet ports 58, 59 and that are alternately arranged in the circumferential direction. And an introduction passage 67 which is provided in the rotary valve body 18, one end of which is always in communication with one end of the supply passage 53, and the other end of which is connected to both the first and second introduction ports 58 and 60, and the rotary valve body. A discharge passage 75, which is provided at 18, has one end always communicating with one end of the discharge passage 73 and the other end connected to both the first and second discharge ports 59 and 61.
And a state in which the rotary valve body 18 rotates so that the first and second supply / discharge ports 23 and 26 communicate with the first introduction and second discharge ports 58 and 61, respectively. Second supply / discharge port 23, 26
And the first outflow port, the second outflow port 59, 60 are repeatedly connected to each other, so that the high-pressure fluid from the supply passage 53 is alternately supplied to the first and second supply / discharge passages 82, 83. In the fluid generating valve for generating vibration, the first and second supply / discharge ports 23, 26 and the first introduction,
A fluid switching valve for vibration generation, wherein the axial length of the second outlet ports 58, 61 is larger than the circumferential length. 2. The vibration generating fluid switching valve according to claim 1, wherein the axial lengths of the first lead-out port and the second introduce port 59, 60 are also larger than the circumferential length. 3. A pressure control valve 54, 55 for controlling the pressure and flow rate of the high-pressure fluid flowing through the supply passage 53 of the vibration-generating fluid switching valve according to claim 1, and flow control valves 54, 55, respectively. First and second supply / discharge passages of the generation fluid switching valve
A cylinder chamber 78 composed of first and second cylinder branch chambers 78a and 78b, which are connected to the other ends of 82 and 83 and are partitioned by a piston 79, is formed in the casing 16, and the vibration generating fluid switching valve The rotating means is composed of the fluid motor 19 to which high-pressure fluid is supplied through the supply passage 53, and is connected to the first and second cylinder branch chambers 78a and 78b on the head side and the rod side through the first and second supply / discharge passages 82 and 83. A vibration generator using a vibration switching fluid switching valve in which a piston 79 is reciprocated in a cylinder chamber 78 by a high pressure fluid supplied alternately to generate vibration.