JP3270401B2 - Vibration device for working cylinder of civil engineering construction machinery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrating device for vibrating a working cylinder used when performing civil engineering work with civil engineering machinery.

[0002]

2. Description of the Related Art In general, civil engineering and construction machines, such as hydraulic excavators, are used for excavating, consolidating, and staking piles of earth and sand. Such operations are performed by working cylinders of the hydraulic excavators, such as booms. , The arm and the bucket cylinder are appropriately operated to scoop up the earth and sand by the bucket or to press the ground and the pile. Here, as described above, if the bucket hits a large stone while excavating earth and sand, high-frequency vibration is applied to the bucket to increase the excavating force. It is empirically known that it can be excavated, and also when consolidating and staking, or when shaking off the soil attached to the bucket,
It is known that these operations can be performed quickly and satisfactorily by applying high-frequency vibration to the bucket.

[0003]

However, in the conventional civil engineering construction machine, the working cylinders, that is, the boom cylinder, the arm cylinder, and the bucket cylinder are merely connected to the fluid source and the discharge source via control valves. Therefore, there has been a problem that the piston rods of these cylinders only protrude and retract smoothly with a large stroke, but cannot vibrate at a high frequency.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vibration device for a working cylinder of a civil engineering construction machine which can switch the working cylinder to a vibration mode while the civil engineering work is being performed by the working cylinder.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a working cylinder vibrating device for a civil engineering construction machine having a working cylinder used in civil engineering work, in which the direction of fluid from a fluid source is alternately repeated. Switching means for switching, a fluid supplied from a fluid source to a rod side chamber of the working cylinder, and a first position for interrupting the supply of the fluid switched by the switching means to the working cylinder, and the fluid Locks the working cylinder of fluid from a source.
This can be achieved by providing a control valve having a second position for shutting off the supply to the work side chamber and supplying the fluid switched by the switching means to the working cylinder.

Now, when the control valve is located at the first position, the fluid from the fluid source is supplied to the working cylinder, whereby the working cylinder is operated to perform civil engineering work, for example, excavation, consolidation, and pile driving. Suppose that it is done. When the working cylinder is vibrated during such work, the control valve is switched from the first position to the second position, and the fluid from the fluid source whose direction has been switched by the switching means is supplied to the working cylinder. At this time, the switching means alternately and repeatedly switches the direction of the fluid from the fluid source, so that the piston of the working cylinder reciprocates and vibrates. As described above, the work cylinder can be easily and reliably switched to the vibration mode while the civil engineering work is being performed by the work cylinder.

[0007] Further, according to the second aspect of the invention, the direction of the fluid can be alternately and reliably switched with a simple structure.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 10 denotes a hydraulic shovel as a civil engineering construction machine.
Has a traveling frame 11 that moves forward or backward as the crawler 12 travels. A swing frame 13 that can swing in a horizontal plane is supported on the traveling frame 11, and a base end of a boom 15 that swings up and down by a boom cylinder 14 is connected to the swing frame 13. A base end of an arm 17 that swings up and down by an arm cylinder 16 is connected to a distal end of the boom 15, and a bucket 19 is connected to a distal end of the arm 17 via a pin 18.
Reference numeral 20 denotes a bucket cylinder as a working cylinder whose head side is connected to the base end of the arm 17, and one end of a piston rod 21 of the bucket cylinder 20 is connected to a tip end of the arm 17 via a pin 22. The other end of the bracket 23 is connected via a pin 24. 25 is bracket 23
The connecting rod 25 is connected between the pin 24 and the distal end thereof is connected to the bucket 19 via the pin 26. When the bucket cylinder 20 is operated, the bucket 19 swings up and down around the pin 18 to perform civil engineering work, for example, excavation of soil, consolidation, pile driving, and the like.

In FIG. 2, reference numeral 30 denotes a manual four-port three-position switching valve installed on the cab of the turning frame 13 of the hydraulic excavator 10, and the switching valve 30 and a fluid source installed on the turning frame 13 are provided. The fluid pump 31 and the tank 32 as a discharge source are connected by a supply passage 33 and a discharge passage 34, respectively. 35 is the fluid pump 31 and tank
A suction passage connecting the suction passage 32 and a relief valve disposed between the supply passage 33 and the tank 32. The bucket cylinder 20 has a cylinder chamber 38 formed therein. The cylinder chamber 38 is slidably housed in the cylinder chamber 38 and has a piston 39 to which the piston rod 21 is connected.
The partition is divided into a head side chamber 38a and a rod side chamber 38b. The switching valve 30 and the head side chamber 38a of the bucket cylinder 20 are connected by one supply / discharge passage 41, and the switching valve
By switching 30, the fluid from the fluid pump 31 is supplied to the head side chamber 38 a or the fluid flowing out from the head side chamber 38 a is discharged to the tank 32. The switching valve 30 and the rod-side chamber 38b of the bucket cylinder 20 are connected by one supply / discharge passage 41 which is paired with the other supply / discharge passage 41. Side room 38b
Or the fluid flowing out of the rod side chamber 38b
Discharge to 32.

Reference numeral 45 denotes a fluid pump as a fluid source connected to a tank 47 via a suction passage 46. A supply passage is provided between the fluid pump 45 and a manual three-port two-position switching valve 48.
The relief valve 50 is interposed between the supply passage 49 and the tank 47. Reference numeral 53 denotes switching means, and the switching means 53 and the switching valve 48
A pilot-type flow control valve 55 (or a pilot-type flow control valve) is interposed in the middle of the supply path 54. In a supply path 54 between the switching valve 48 and the flow control valve 55, a branch path 57 in which a pilot-type flow control valve 56 (or a pilot-type flow control valve may be interposed) is provided. One end is connected, and the other end of the branch path 57 is connected to the switching means 53. These flow control valves 55 and 56 are connected to a fluid motor 75 to be described
The fluid from 45 is adjusted so as to flow in advance.
Reference numeral 60 denotes a discharge path connecting the switching means 53 to the tank 61 serving as a discharge source, and reference numerals 62 and 63 denote a pair of connection paths connected to the switching means 53. As a result, the switching means 53 is interposed between the pair of connection passages 62 and 63 and the fluid pump 45 and the tank 61. The switching means 53 includes a state in which the one connection passage 62 and the fluid pump 45 are connected to each other and the other connection passage 63 and the tank 61 are connected to each other, and a state in which the one connection passage 62 and the tank 61 are connected to each other and the other connection passage 63. The direction of the fluid from the fluid pump 45 is alternately and repeatedly switched by alternately and repeatedly switching at a high frequency between a state in which the fluid pumps 45 are connected to each other.

2, 3, 4, 5, 6, 7, 8, 9, 1
In FIGS. 0, 11, and 12, the switching means 53 has an intermediate block 69 that is housed in the housing hole 68 of the case body 67 and has a shorter axial length than the housing hole 68. A valve chamber 70 having a circular cross section is formed extending toward. In the storage hole 68 on the base end side of the intermediate block 69, a disk-shaped partition plate 72 in which a connection hole 71 penetrating in the center is formed is disposed, and in the storage hole 68 on the base end side of the partition plate 72. Accommodates a disk-shaped fixing plate 73. Here, the fixing plate 73 is a partition plate 72
, And as a result, the storage hole 68 between the partition plate 72 and the fixing plate 73 becomes a space, and forms the motor chamber 74. As a result, the motor chamber 74 and the valve chamber 70 are connected via the connection hole 71.

An internal gear type fluid motor 75 is housed in the motor chamber 74. The fluid motor 75 has a substantially cylindrical internal gear having a plurality of, here five, internal teeth 76 formed on an inner periphery thereof. 77
And the internal teeth of the internal gear 77
A plurality of external teeth 78, which is one less than the internal teeth 76, are formed in mesh with the external gears 79, and the external gears 79 eccentrically rotate (revolve) about the axis of the internal gear 77. At the center of the gear 79, a penetrating spline hole 81 having a spline internal tooth 80 on the inner periphery is formed. 82 is a storage hole
68 is a cover for closing the base opening of the case 68, and the cover 82 is fixed to the base end of the case body 67. Reference numeral 84 denotes a pin that passes through the intermediate block 69, the partition plate 72, the internal gear 77, and the fixed plate 73.
It is inserted and fixed to 67 and cover 82, respectively. As a result, the intermediate block 69, the partition plate 72, the internal gear 77,
The fixing plate 73 is fixed while being prevented from rotating by the case body 67 and the cover 82. The above-described case body 67, intermediate block 69, partition plate 72, fixing plate 73, and cover 82 as a whole have a motor chamber 74 therein.
A casing 85 in which a valve chamber 70 coaxial with the motor chamber 74 and a connection hole 71 connecting the motor chamber 74 and the valve chamber 70 are formed.
Is configured.

A thrust bearing 88 and a cylindrical rotary valve body 90 having a through hole 89 formed therein are housed in the valve chamber 70. The rotary valve body 90 is provided with an internal gear 77 of a fluid motor 75.
And can rotate around the axis while maintaining the coaxial relationship. Further, spline internal teeth 91 are formed on the inner periphery of the through hole 89 of the rotary valve body 90. The above-described intermediate block 69 and the rotary valve body 90 constitute a rotary valve 92 as a whole. 95
Is a connecting rod penetrating through the connecting hole 71, the distal end side of the connecting rod 95 is inserted into the through hole 89, and the proximal end side is inserted into the spline hole 81. And this connecting rod
The spline external teeth 96 formed on the outer periphery of the distal end of the mesh 95 mesh with the spline internal teeth 91, and the spline external teeth 97 formed on the base outer circumference mesh with the spline internal teeth 80. Connects the rotary valve element 90 and the external gear 79 of the fluid motor 75. And this connecting rod
95 transmits the rotation of the external gear 79 of the fluid motor 75 to the rotary valve body 90 while precessing around the tip, and
Rotate 90 around the axis. The switching means described above
53 is composed of only the fluid motor 75, the rotary valve 92, and the connecting rod 95, so that the structure is simple, and the flow direction of the fluid can be reliably switched.

Reference numeral 99 denotes a discharge annular groove formed between the inner periphery of the valve chamber 70 and the outer periphery of the rotary valve body 90, more specifically, formed on the outer periphery of the rotary valve body 90 and extending continuously in the circumferential direction. A communication hole 100 extending in the radial direction communicating with the through hole 89 is provided on the bottom of the groove 99.
Are formed. Reference numeral 101 denotes a discharge hole whose one end is opened at the outer periphery of the center of the connecting rod 95, and the other end of the discharge hole 101 is opened at the base end surface of the connecting rod 95. Reference numeral 102 denotes a discharge passage formed in the casing 85, specifically, in the fixed plate 73 and the cover 82, one end of which communicates with the spline hole 81 and the other end of which is opened on the outer periphery of the cover 82. Is connected to the discharge path 60. The discharge passage 102 extends from the discharge annular groove 99 to the communication hole 100 and the through hole 8.
9. The fluid flowing out to the spline hole 81 through the discharge hole 101 is discharged from the switching means 90 to the tank 61. Reference numerals 104 and 105 denote first and second supply annular portions provided between the inner periphery of the valve chamber 70 and the outer periphery of the rotary valve body 90, here, on the outer periphery of the rotary valve body 90 on both axial sides of the discharge annular groove 99. Grooves, these first,
The second supply annular grooves 104 and 105 both extend continuously in the circumferential direction. 106 is inside the casing 85, specifically the intermediate block
69, a partition plate 72, an internal gear 77, a fixed plate 73, and a first supply passage formed in the cover 82. One end of the first supply passage 106 communicates with the first supply annular groove 104,
The other end is open to the outer periphery of the cover 82. The other end opening of the first supply passage 106 is connected to the branch passage 57, whereby the first supply passage 106 is connected to the fluid pump 45.
Can be supplied to the first supply annular groove 104. 108 is inside the casing 85, specifically the middle block
69, a partition plate 72, an internal gear 77, a fixed plate 73, and a cover 82.
The second supply passage 108 is arranged at a predetermined angle in the circumferential direction from the second supply passage 108. One end of the second supply passage 108 communicates with the second supply annular groove 105, and the other end is opened to the outer periphery of the cover 82. I have. Then, the other end opening of the second supply passage 108 is connected to the supply passage 54, whereby the second supply passage 108 can supply the fluid from the fluid pump 45 to the second supply annular groove 105.

Reference numeral 110 denotes a plurality of first grooves formed on the outer periphery of the rotary valve body 90 at equal intervals in the circumferential direction.
The concave groove 110 extends in the axial direction from the first supply annular groove 104 toward the discharge annular groove 99. 111 is a plurality of second concave grooves formed on the outer periphery of the rotary valve body 90 at equal distances in the circumferential direction,
These second grooves 111 extend in the axial direction from the second supply annular groove 105 toward the discharge annular groove 99. 112 is a rotary valve
While being formed on the outer circumference of 90 at equal distances in the circumferential direction,
A plurality of third grooves alternately arranged in the circumferential direction with the first grooves 110; these third grooves 112 extend in the axial direction from the discharge annular groove 99 toward the first supply annular groove 104; ,
The distal end portion of the first supply annular groove 104 close to the discharge annular groove 99 of the first concave groove 110 circumferentially overlaps with the distal end portion of the first concave groove 110. Reference numeral 113 denotes a plurality of fourth grooves formed on the outer periphery of the rotary valve body 90 at equal intervals in the circumferential direction and alternately arranged with the second grooves 111 in the circumferential direction. 113
Extends in the axial direction from the discharge annular groove 99 toward the second supply annular groove 105, and the distal end near the second supply annular groove 105 is formed around the distal end of the second concave groove 111 near the discharge annular groove 99. Overlap in the direction.

Reference numeral 116 denotes a plurality of supply / discharge passages formed in the casing 85, specifically, in the intermediate block 69 and the partition plate 72, at equal intervals in the circumferential direction, in this case, the same number of supply and discharge passages as the internal teeth 76 of the internal gear 77. One end of these supply / discharge passages 116 is connected to the first,
An opening is formed on the inner periphery of the valve chamber 70 so as to face the overlapping portion between the third concave grooves 110 and 112, and the other ends are the internal gear 77 and the external gear 79.
Between the internal teeth 76. These supply / discharge passages 116 supply the fluid from the first groove 110 to the fluid chamber 117 or supply the fluid from the fluid chamber 117 to the third
The fluid is discharged into the concave groove 112. 119 and 120 are casing 85
Among them, more specifically, a plurality of, here two, guide passages formed in the intermediate block 69 at a distance in the circumferential direction, and one end of each of the guide passages 119 and 120 has a second groove 111 and a fourth groove 113.
An opening is formed on the inner periphery of the valve chamber 70 so as to face the overlapped portion, and the other end is opened on the front end surface of the intermediate block 69. And these guide passages 119 and 120 are the second concave grooves 1
In addition to guiding the fluid from 11, the fluid is guided to the fourth groove 113.

Referring to FIGS. 2 and 3, a control valve 124 is provided in a case body 67 at the end side of the intermediate block 69.
The control valve 124 is formed in the case body 67 and has a cap
A spool chamber 125 extending in the radial direction, one end of which is closed by 126, a spool 127 movably housed in the spool chamber 125, and the other end of the spool 127 and the other end surface (bottom surface) of the spool chamber 125 And a spring 128 as an elastic body which is interposed therebetween and biases the spool 127 toward one end. Then, first, second, third, and fourth lands 129, 130, 131, and 132 are sequentially formed from one end to the other end of the spool 127. As a result, the first, second, and third lands are formed. , 4th land 1
1st, 2nd, 3rd annular grooves 1 between 29, 130, 131, 132
33, 134 and 135 are provided.

The switching means 5 is provided in the case body 67.
3.Specifically, a pair of passages whose base ends are respectively connected to the guide passages 119 and 120 are formed, and these passages are the above-described connection passages 62 and 63, and these connection passages 62, 63
The distal end of 63 is connected to the control valve 124, and more specifically, is opened at a central portion in the axial direction of the spool chamber 125 so as to be spaced apart in the axial direction.
137 is formed in the case body 67, and one end is connected to the connection passages 62, 6
3 and the other end of the case body 67
The first passage opened on the outer periphery of the case body 138 is the case body 67
A second end of which is opened in the spool chamber 125 having one end facing the first passage 137 and the other end opened in the tip end face of the case body 67.
These first and second passages 137 and 138 constitute a part of the other supply / discharge passage 42. As a result, the control valve 124 is interposed in the other supply / discharge passage 42. Third and 139 and 140 are formed in the case body 67, and have one end opened to the spool chamber 125 facing the connection passages 62 and 63, and the other end opened to the tip end surface of the case body 67.
The third and fourth passages 139 and 140 are paired communication passages each having one end connected to the control valve 124 and the other end connected to one of the supply and discharge passages 41 and 42. 1
Part of 41, 142. As a result, one communication passage
141 connects the head side chamber 38a of the bucket cylinder 20 to the control valve 124 via one supply / discharge passage 41, and the other communication passage 142 connects the bucket cylinder 20 via the other supply / discharge passage 42.
Is connected to the control valve 124. Also, 143 is a casing 85, specifically the case body 6
7. A fifth passage formed in the cover 82, one end of which is open to the spool chamber 125 on one end side of the connection passages 62 and 63, and the other end of which is open to the outer periphery of the cover 82. Pilot passage 144 connecting switching valve 48 and control valve 124
A part of. When the switching valve 48 is switched to the flow position, the high-pressure fluid discharged from the fluid pump 45 flows into the spool chamber 125 on one side from one end face of the spool 127 through the pilot passage 144, and the other fluid flows into the spool 127. Apply fluid force toward the side. As a result, spool 1
27 moves to the other side against the spring 128, and the control valve 124 is switched from the first position T to the second position S. Here, when the switching valve 124 is located at the first position T, the first and second passages 137 and 138, that is, the other supply / discharge passage
42 communicates through the third annular groove 135 of the spool 127, but the connection passages 62 and 63 and the communication passages 141 and 142 (the third and fourth passages 139 and 140) are connected to the third and second lands of the spool 127. Since they are blocked by 131 and 130, the fluid from the fluid pump 31 flows through the supply / discharge passage 41 or 42 to the head side chamber 38a or the rod side chamber 38 of the bucket cylinder 20.
b. On the other hand, when the switching valve 124 is located at the second position S, the first and second passages 137 and 138, that is, the other supply / discharge passage 42 are shut off by the third land 131 of the spool 127. Passages 62, 63 and communication passage 141,
142 (third and fourth passages 139 and 140) communicate with the spool 127 through the second and first annular grooves 134 and 133, respectively, so that the fluid is switched by the switching means 53 and the fluid is transferred to the head side chamber of the bucket cylinder 20. 38a or rod side chamber
38b. Reference numeral 150 denotes an air vent hole formed in the case body 67.

Next, the operation of the first embodiment of the present invention will be described. Now, the switching valve 30 has been switched to the cross flow position, while the control valve 124 is located at the first position T, and communicates with the other supply / discharge passage 42, and has the communication passages 141, Suppose that it is shut off with 142. At this time, the high-pressure fluid discharged from the fluid pump 31 is supplied to the switching valve 30,
It is supplied to the head side chamber 38a of the bucket cylinder 20 through one supply / discharge passage 41, and operates the bucket cylinder 20 to move the piston 39 and the piston rod 21 to the protruding side. Thereby, the bucket 19 of the excavator 10 rotates, and performs civil engineering construction work, for example, excavation work of earth and sand. At this time, the low-pressure return fluid flowing out of the rod-side chamber 38b of the bucket cylinder 20 is supplied to the control valve 124 at the first position T.
The other supply / discharge passage 42, the switching valve 30,
It is discharged to the tank 32 through the discharge passage 34.

If the bucket 19 hits a large stone during the excavating operation and the excavation cannot be easily performed, the switching valve 48 is switched from the shut-off position to the flow position, and the high pressure discharged from the fluid pump 45 is discharged. The fluid is guided to one end of the spool 127 of the control valve 124 through the pilot passage 144 (fifth passage 143), and the spool 127 is moved to the other side against the spring 128. As a result, the control valve 124 is switched from the first position T to the second position S, and the other supply / discharge passage 42 is interrupted halfway by the third land 131, while the connection passages 62, 63 and the communication passages 141, 142 are provided.
Are communicated through the second and first annular grooves 134 and 133, respectively.

By switching the switching valve 48 to the flow position, the high-pressure fluid from the fluid pump 45 is supplied through the supply passage 54, the branch passage 57, and the first and second supply passages 106 and 108 to the first and second supply passages. It is supplied to the annular grooves 104 and 105. At this time, a certain supply / discharge passage 116 is inserted into the first groove 110,
Communicate with the second groove 111, the remaining supply / discharge passage 116 communicates with the third groove 112, and the guide passage 120 communicates with the fourth groove 111.
Assuming that they are in communication with the respective 113, high-pressure fluid is supplied from the first supply annular groove 104 to a part of the fluid chamber 117 of the fluid motor 75 through the aforementioned supply / discharge passage 116. Thus, the external gear 79 of the fluid motor 75 receives driving force from the inflowing fluid and rotates eccentrically (revolves) about the axis of the internal gear 77. At this time, the external gear 79 has only one tooth. Since many internal gears 77 are engaged with each other, the external gear 79 also rotates around its own axis in addition to revolving. Here, connecting rod 95
The spline external teeth 96 and 97 of the fluid motor 75 mesh with the spline internal teeth 91 and 80 of the external gear 79, respectively, so that the rotational driving force based on the rotation of the external gear 79 of the fluid motor 75 causes precession. The rotation is transmitted to the rotary valve body 90 through the connecting rod 95, and the rotary valve body 90 is rotated around the axis. At this time,
The return fluid is pushed out from the remaining portion of the fluid chamber 117 of the fluid motor 75 to the remaining supply / discharge passage 116, and this fluid is supplied to the third groove 1
12, discharge annular groove 99, communication hole 100, through hole 89, discharge hole 10
1. Discharged to the tank 61 through the discharge passage 102 and the discharge passage 60. On the other hand, the high-pressure fluid supplied to the second supply annular groove 105 is supplied to the guide passage 119, the connection passage 62, and the second annular groove of the control valve 124.
134, communication passage 141 (third passage 139), one supply / discharge passage
41 to the head side chamber 38a of the bucket cylinder 20 and the rod side chamber 38b of the bucket cylinder 20.
Are the other supply / discharge passage 42, the communication passage 142 (the fourth passage 140),
First annular groove 133 of control valve 124, connection passage 63, guide passage 1
20, fourth concave groove 113, discharge annular groove 99, communication hole 100, through hole
89, the discharge hole 101, the discharge passage 102, and the discharge passage 60 are discharged to the tank 61. As a result, the high-pressure fluid from the fluid pump 45 flows into the head-side chamber 38a of the bucket cylinder 20 in addition to the high-pressure fluid from the fluid pump 31 that is constantly supplied, and the piston 39 and the piston rod 21 are slightly more than usual. Protrude a lot.

Next, when the rotary valve element 90 slightly rotates by receiving the rotational driving force from the fluid motor 75, the supply / discharge passage 1
The communication between the first groove 16 and the first and third concave grooves 110 and 112 is displaced in the circumferential direction, and the position where the high-pressure fluid is supplied is moved in the circumferential direction, whereby the external gear 79 of the fluid motor 75 is moved in the same direction. Continue spinning. At this time, the return fluid discharged from the fluid motor 75 is also discharged to the discharge annular groove 99, the discharge passage 102, and the discharge passage 60.
Through the tank 61. On the other hand, due to the rotation of the rotary valve body 90 described above, the guide passage 119 which has been in communication with the second groove 111 up to now has the guide passage 120 which has been in communication with the fourth groove 113 and the fourth groove 113. Is connected to the second concave groove 111, and the high-pressure fluid from the fluid pump 45 is supplied to the second supply annular groove 105, the guide passage 120, the connection passage 63, and the first of the control valves 124.
The rod-side chamber 38b of the bucket cylinder 20 passes through the annular groove 133, the communication passage 142 (the fourth passage 140), and the other supply / discharge passage 42.
It will flow into. At this time, the bucket cylinder 20
The head side chamber 38a is connected to the tank 61,
The fluid in 38a is supplied to one of the supply / discharge passage 41, the communication passage 141, the second annular groove 134 of the control valve 124, the connection passage 62, the guide passage 119,
4th concave groove 113, discharge annular groove 99, communication hole 100, through hole 89,
Tank 61 through discharge hole 101, discharge passage 102, discharge passage 60
Is discharged to As a result, the pressure in the head-side chamber 38a of the bucket cylinder 20 decreases even though the high-pressure fluid is supplied from the fluid pump 31, and the pressure in the rod-side chamber 38b becomes high, and the piston 39 and the piston rod 21 are slightly retracted. .

Next, when the rotary valve element 90 is further rotated slightly in the same direction by the fluid motor 75, the supply / discharge passage 116 and the first,
The form of communication with the third grooves 110 and 112 is further shifted in the circumferential direction, and the second groove 111 is provided in the guide passage 119 and in the fourth groove 113.
Communicates with the guiding passages 120, respectively.
The high-pressure fluid from the fluid pump 45 flows into the head-side chamber 38a of the bucket cylinder 20. Thus the switching valve
When the switch 48 is switched to the flow position, the one connection passage 62 and the fluid pump 45 are connected to each other, and the other connection passage 63 and the tank 61 are connected to each other, and the one connection passage 62 and the tank 61 are connected to each other. At the same time, the other connection passage 63 and the state in which the fluid pumps 45 are connected to each other are alternately and repeatedly switched at a high frequency, that is, the flow direction of the fluid from the fluid pump 45 is alternately and repeatedly switched. ,
One communication passage 141, the head side chamber of the bucket cylinder 20
The high-pressure fluid from the fluid pump 45 whose direction has been switched is alternately and repeatedly supplied to the connection passage 63a, the other connection passage 63, the other communication passage 142, and the rod-side chamber 38b of the bucket cylinder 20. As a result, the piston of the bucket cylinder 20
Fluid force toward the projecting side and the retreating side acts on 39 repeatedly, and as a result, the piston 39 vibrates back and forth at a high frequency while moving to the projecting side. As described above, during the construction work (digging work) by the bucket cylinder 20, the bucket cylinder 20 can be easily and reliably switched to the vibration mode. And
When the piston 39 vibrates as described above, the bucket 19 vibrates at a high frequency while being pressed against the stone, so that the excavating force increases. As a result, even if the bucket 39 hits a large stone, it can be easily excavated. It becomes. Here, the piston 39 and the bucket 19 are hydraulic excavators.
In order not to cause resonance with the hydraulic excavator 10, the hydraulic excavator 10 is caused to vibrate at a high frequency exceeding a resonance frequency to some extent. When a large stone is dug up in this way, the switching valve 48
Is switched from the flow position to the shutoff position, and the control valve 124 is switched from the second position S to the first position T so that only the fluid from the fluid pump 31 is supplied to the bucket cylinder 20.

When the bucket 19 scoops the earth and sand, the revolving frame 13 is appropriately rotated, and the boom cylinder 14 and the arm cylinder 16 are appropriately operated to move the bucket 19 to just above the discharge position. Next, the bucket 19 is turned over to discharge the scooped earth and sand from the bucket 19. In this case, the switching valve 30 is switched to the parallel flow position, and the fluid pump 31 is connected to the other supply / discharge passage 42. At the same time, the tank 32 is connected to one supply / discharge passage 41, and the high pressure fluid from the fluid pump 31 is supplied to the rod side chamber 38b of the bucket cylinder 20 through the other supply / discharge passage 42, the first position T.
Through the control valve 124 to move the piston 39 and the piston rod 21 to the retracted side. At this time, the low-pressure return fluid flowing out of the head-side chamber 38a of the bucket cylinder 20 is discharged to the tank 32 through one supply / discharge passage 41.

In the course of such reversal, if the picked-up earth and sand is soft and adheres to the bucket 19 in a large amount, an operation of shaking off the attached earth and sand from the bucket 19 is performed. In such cases, the bucket
When 19 is rotated to an appropriate position, the switching valve 48 is switched from the shut-off position to the flow position, and the control valve 124 is switched from the first position T to the second position S. As a result, the other supply / discharge passage 42 that has been supplying high pressure to the rod-side chamber 38b of the bucket cylinder 20 is now connected to the third land 1 of the spool 127 of the control valve 124.
The fluid is interrupted on the way by 31 and the fluid from the fluid pump 31 cannot be supplied to the rod side chamber 38b. At this time, the high-pressure fluid from the fluid pump 45 is alternately and repeatedly supplied to the head-side chamber 38a and the rod-side chamber 38b of the bucket cylinder 20 through the communication passages 141 and 142 at a high frequency by the same operation of the switching means 53 as described above. As a result, the piston 39 does not move to the projecting side as described above, but vibrates back and forth at a high frequency around the stopped position, and
It shakes off the earth and sand. Note that such a swing-down operation can also be performed by switching the switching valve 30 to the neutral position and then switching the switching valve 48 to the flow position after the piston 39 reaches the stroke end on the retracted side. As described above, since the vibration function is provided to the already installed bucket cylinder 20, there is no need to install a special cylinder for vibration, and the structure of the vibration device is simplified. Then, when the work of shaking off the soil is completed, the switching valve 48 is switched from the flow position to the shut-off position.

FIG. 13 is a view showing a second embodiment of the present invention. In this embodiment, the other supply / drain passage between the switching valve 30 and the control valve 124 is different from that of the first embodiment.
A pilot passage 153 for connecting the control valve 42 and the control valve 124 is added. Specifically, although not shown, the spool chamber 125 on the other side from the other end of the spool 127 is provided in the middle of the first passage 137. A passage extending to the air passage is formed, and the air vent hole 150 is omitted. When such a pilot passage 153 is provided, when the other supply / discharge passage 42 has a high pressure, the high-pressure fluid in the other supply / discharge passage 42 is supplied to the control valve 124 and acts on the other end of the spool 127. Therefore, the control valve 124 is fluidly locked at the first position T. As a result, the control valve 124 can be prevented from switching from the first position T to the second position S when the piston 39 is moving to the retracted side, and the vibration device is moved to the piston position.
It can be specialized to apply vibration only when moving to the projecting side of 39.

FIG. 14 is a view showing a third embodiment of the present invention. In this embodiment, the communication passage 141 is not connected in the middle of one of the supply / discharge passages 41,
It is directly connected to the head side chamber 38a of 20 and its connection position is located at a position which is substantially half a circle away from the connection position of the one supply / discharge passage 41. In this way, when the switching valve 30 is switched to the cross flow position, the high-pressure fluid discharged from the fluid pump 31 is once supplied to the head side chamber of the bucket cylinder 20.
38a. Other configurations and operations are the same as those of the second embodiment.

FIG. 15 is a view showing a fourth embodiment of the present invention. In this embodiment, a control valve 156 to which a pair of connection passages 62 and 63 are connected is provided in the middle of one supply / discharge passage 155 connecting the switching valve 30 and the head-side chamber 38a of the bucket cylinder 20, When the control valve 156 is in the first position T
When the second position S is located at the second position S, the communication passages 155 communicate with one of the supply / discharge passages 155, and the connection passages 62, 63 are disconnected from the communication passages 141, 142. While blocking the supply / discharge passage 155, the connection passages 62 and 63
And the communication passages 141 and 142, respectively. With this configuration, the switching valve 30 is switched to the cross flow position and the rod-side chamber 38b of the bucket cylinder 20 is
High-pressure fluid from the fluid pump 31 is supplied to the piston 39
When the is moved to the retracted side, the earth and sand attached to the bucket 19 can be quickly and reliably shaken off. That is, at this time, the control valve 156 is switched from the first position T to the second position S so that the connection passages 62 and 63 communicate with the communication passages 141 and 142 and the fluid pump 45
The high-pressure fluid discharged from the hopper is alternately and repeatedly supplied to the head-side chamber 38a and the rod-side chamber 38b of the bucket cylinder 20 by the switching means 53, whereby the piston 39 is vibrated back and forth at a high frequency while being moved to the retracted side. As a result, the bucket 19 vibrates, and the earth and sand adhering to the bucket 19 are quickly and reliably shaken off. Other configurations and operations are the same as those of the second embodiment. In this embodiment, when the switching valve 30 is switched to the parallel flow position to supply the fluid to the head-side chamber 38a of the bucket cylinder 20 and move the piston 39 to the projecting side, that is,
When the bucket 19 is excavating earth and sand, even if the switching valve 48 is switched to the flow position and the control valve 156 is switched from the first position T to the second position S, one of the supply / discharge passages 155 is used.
The high pressure fluid in the control valve 156 passes through the pilot passage 153.
The control valve 156 is fluidly locked at the first position T, and is not switched to the second position S. However, when the pilot passage 153 is omitted,
As described above, the control valve 156 is switched to the second position S, and the piston 39 of the bucket cylinder 20 vibrates back and forth at the stop position without moving to the projecting side or the retracting side.

FIG. 16 is a view showing a fifth embodiment of the present invention. In this embodiment, the communication passage 142 is directly connected to the rod-side chamber 38b of the bucket cylinder 20, and the other supply / discharge passage 157 is connected to the rod-side chamber 38b at a position approximately half a distance from the communication passage 142. In this way, the high-pressure fluid from the fluid pump 31 can be once flowed into the rod-side chamber 38b of the bucket cylinder 20.

In the above-described embodiment, the bucket 19 is vibrated when digging a large stone by the bucket 19. In the present invention, the bucket 19 is vibrated when the bucket 19 is compacted. Thus, the consolidation may be performed quickly and favorably. Further, in the present invention, when the work cylinder is the arm cylinder 16, and the slope of the slope is compacted by the bucket 19, the piston of the arm cylinder 16 is vibrated so that the compaction of the slope is performed quickly and favorably. Or the working cylinder can be
When the stakeout is being performed by the bucket 19, the piston of the boom cylinder 14 may be vibrated so that the stakeout is quickly and favorably performed. At this time, since two boom cylinders 14 are usually installed, two sets of the above-described vibration devices may be provided in parallel, and these two boom cylinders 14 may be separately controlled. One set of such a vibrating device may be provided, and the two boom cylinders 14 may be controlled collectively by branching from the middle. Further, in the above-described embodiment, the fluid pumps 31 and 45 and the tanks 32, 47 and 61 are separately provided. However, a single fluid pump and tank may be collectively provided.

[0031]

As described above, according to the present invention, the work cylinder can be switched to the vibration mode during the civil engineering work by the work cylinder. And the civil engineering construction work can be efficiently and easily performed by such a vibration work.

[Brief description of the drawings]

FIG. 1 is a schematic overall front view showing a state in which a first embodiment of the present invention is applied to a hydraulic shovel.

FIG. 2 is a circuit diagram thereof.

FIG. 3 is a front sectional view of the switching means.

FIG. 4 is a plan view of the switching means.

FIG. 5 is a sectional view taken along the line AA of FIG. 3;

FIG. 6 is a sectional view taken along the line BB in FIG. 3;

FIG. 7 is a sectional view taken along the line CC of FIG. 3;

8 is a sectional view taken along the line DD in FIG.

FIG. 9 is a sectional view taken along the line EE in FIG. 3;

FIG. 10 is a sectional view taken along the line FF in FIG. 3;

FIG. 11 is a sectional view taken along the line GG of FIG. 3;

FIG. 12 is a sectional view taken along the line HH of FIG. 3;

FIG. 13 is a circuit diagram of a second embodiment of the present invention.

FIG. 14 is a circuit diagram near a control valve showing a third embodiment of the present invention.

FIG. 15 is a circuit diagram of a fourth embodiment of the present invention.

FIG. 16 is a circuit diagram near a control valve showing a fifth embodiment of the present invention.

[Explanation of symbols]

 10 ... Civil engineering machinery 20 ... Working cylinder 31, 45 ... Fluid source 53 ... Switching means 75 ... Fluid motor 90 ... Rotary valve body 92 ... Rotary valve 124 ... Control valve T ... First position S ... Second position

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F15B 11/00 F15B 21/12 E02F 9/22

Claims (2)

(57) [Claims] 1. A vibration device for a working cylinder of a civil engineering construction machine having a working cylinder used for performing a civil engineering work, a switching means for alternately and repeatedly switching a direction of a fluid from a fluid source, and a fluid from the fluid source. Is supplied to the rod-side chamber of the working cylinder, and the first position at which the supply of the fluid switched by the switching means to the working cylinder is interrupted, and the supply of the fluid from the fluid source to the rod-side chamber of the working cylinder While blocking
And a control valve having a second position for supplying the fluid switched by the switching means to the work cylinder. 2. The vibration device for a working cylinder of a civil engineering construction machine according to claim 1, wherein said switching means has a rotary valve having a rotary valve body and a fluid motor for rotating said rotary valve body.