JP3321405B2 - Forward and backward operation mechanism of vibration compaction machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eccentric pendulum that rotates on a parallel axis and changes the phase of rotation of one eccentric pendulum with respect to the other eccentric pendulum, and moves the body forward and backward by a combined vector. More particularly, the present invention relates to a relatively large vibration compaction machine that uses a hydraulic servo mechanism as a forward / reverse switching operation for changing the phase of rotation of one pendulum.

[0002]

2. Description of the Related Art Conventionally, a vibration compaction machine of this type which changes the phase of rotation of one eccentric pendulum with respect to the other eccentric pendulum among a pair of eccentric pendulums and gives forward / backward movement to the body by a combined vector thereof. Among them, various types are known, and among those using hydraulic power for forward / reverse switching operation for changing the rotation phase of one eccentric pendulum, for example, Japanese Patent Publication No. Sho 61-48997 JP-A-63-60306, JP-B-5-17323, and JP-A-7-286306 (Japanese Patent No. 2513586).

[0003] In these vibration compactors, a spiral groove is provided inside a driven gear on a driven shaft that receives rotation from a drive shaft, and a pin that engages with the spiral groove of the driven gear is provided in the driven shaft. A eccentric pendulum on the driven shaft is provided with respect to an eccentric pendulum on the drive shaft by providing a forward / backward switching shaft having the same and moving the forward / backward switching shaft in the axial direction and rotating a driven gear having a spiral groove. Is common in that the phase of the rotation is changed.

[0004]

Among the compacting machines described above, the compacting machine disclosed in Japanese Patent Publication No. 61-48997 has a driven shaft as a cylinder, a forward / reverse switching shaft as a piston, and a pendulum on the driven shaft as a drive shaft. The combined thrust to rotate in combination with the upper pendulum gives the piston-like forward / reverse switching shaft a mechanical return force to move to one side of the cylindrical driven shaft, and the pressure provided at one end of the cylindrical driven shaft. In the medium chamber, an external pressure supply device applies an oil pressure against a mechanical return force of the piston-like forward / reverse switching shaft, and the supply amount of the pressure oil is variably adjusted so that the driven gear is driven. It is characterized in that the rotation angle can be selected to a position suitable for changing the phase of the eccentric pendulum.

However, in this compacting machine, a combined thrust of the rotating eccentric pendulum opposes a mechanical return force for moving the piston-like forward / reverse switching shaft to one side of the cylinder, and an external pressure supply device. Since the means for sending oil pressure into the pressure medium chamber provided at one end of the cylindrical driven shaft is a hand-operated pump, the piston-like forward / reverse switching shaft receives the maximum mechanical return force and From the forward or reverse maximum speed position moving to one side,
A large amount of labor is required to switch the hand-operated pump to the opposite side to pump the pressure oil into the pressure medium chamber. Especially, in the case of a compacting machine having a large body weight, the switching operation force becomes heavy and cannot be operated. There is a point.

In the compacting machine disclosed in Japanese Patent Publication No. 5-17323, a forward / reverse switching shaft is arranged in a driven shaft so as to be able to maintain neutrality by springs on both sides, and pistons are provided at both ends of the forward / backward switching shaft, respectively. And a cylinder,
Both cylinders are connected to an external pressure supply device, and pressurized oil is sent from the external pressure supply device into one of the cylinders so that the forward / reverse switching shaft can be moved. As for the machine, the means for sending hydraulic pressure into each cylinder is a hand-operated type pump, and therefore, as with the compacting machine of the above-mentioned JP-B-61-48997, it is necessary to send a large amount of oil into the cylinder. There is a problem that it requires labor and cannot be used for a compacting machine having a large switching operation force and a large body weight.

On the other hand, in the compacting machine disclosed in Japanese Patent Application Laid-Open No. 63-60306, a piston and a cylinder are provided at one end of a forward / reverse switching shaft in a driven shaft, and the cylinder is provided with three directions of forward, reverse and neutral. A switching valve is provided, and a hydraulic pump circuit in which these valves always return to a neutral position by the force of a spring is connected, and pressure oil is supplied to the cylinder from the pressure of the hydraulic pump through a forward valve and a reverse valve. This compacting machine has the advantage that the pressure oil by the power of the hydraulic pump can be sent to the cylinder at one end of the forward / reverse switching shaft, so that the switching operation force is light and the speed can be controlled. On the other hand, since the switching valve always returns to the neutral position due to the force of the spring, the operation lever cannot be fixed and held at any tilted position. There is a problem that it is difficult.

Further, in the compacting machine disclosed in Japanese Patent Application Laid-Open No. 7-286306, similarly to the compacting machine described in Japanese Patent Publication No. 5-17323, the forward / reverse switching shaft can be maintained neutral in the driven shaft by springs on both sides. And a piston and a cylinder are provided at both ends of the forward / reverse switching shaft, respectively.
A hydraulic pump circuit equipped with a three-way switching valve for forward, reverse, and neutral is connected to both cylinders as an external pressure supply device, and forward and backward switching is performed by sending pressure oil from either valve to each cylinder. The shaft is switched to any one of forward, reverse and neutral directions.

However, in this compacting machine, hydraulic oil can be supplied to the cylinders at both ends of the forward / reverse switching shaft by the power of a hydraulic pump, so that the switching operation force can be reduced, but switching to forward and backward valves is performed. Therefore, all the hydraulic oil from the hydraulic pump is sent in that direction, and the forward and reverse speeds are set to the running state with the highest speed. Therefore, there is a problem that the running speed cannot be adjusted to an arbitrary speed. .

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in a conventional vibration compacting machine of this type, and is provided with a method for changing the phase of rotation of one eccentric pendulum in an exciter. For the forward switching operation, using a hydraulic pump circuit having a servo function as an external pressure supply device, even if the body weight is 500 kg or more, a large compaction machine,
The switching operation of the forward / reverse switching shaft can be made extremely light, and the operating lever can be set at any position between the fastest forward speed and the farthest reverse position so that the vehicle can run at a desired speed. It is intended to provide a compacting machine.

[0011] The present invention, as a specific means for that,
An eccentric pendulum that can change the phase of rotation with respect to the eccentric pendulum on the other axis is provided on one of the interlocked parallel axes, and forward and backward switching is performed within the eccentric pendulum axis to change the phase of the eccentric pendulum The forward / backward switching shaft is slidably inserted, and the forward / backward switching shaft is axially moved at one end on the axis of the forward / backward switching shaft by hydraulic pressure against a mechanical return force generated by rotation of the eccentric pendulum. In a vibration compaction machine equipped with a vibration exciter having a hydraulic cylinder for switching the rotation of the pendulum between forward and backward directions, a forward and backward operation device connected to the hydraulic silling includes a forward and backward movement in a cylindrical body. A piston receiving one end of a mechanical return force applied from the direction of the switching shaft, and a spool interlocked with an operation lever slidably inserted into the other end of the piston; Between the piston and the piston, a servo valve mechanism for supplying pressure oil sent from a hydraulic pump outside the body to the other end of the piston as a pressure opposing a mechanical return force from the forward / reverse switching axial direction. It is characterized by having.

A piston slidably inserted into the body is formed by inserting a vertical cylinder perpendicular to the body axis direction connected to the tank-side port of the body into an elongated hole along the length direction of the piston. The piston reciprocates left and right without rotating in the body, and the spool interlocked with the left side of the long hole of the piston via an operation lever outside the body is slidably inserted. preferable.

[0013] The spool inserted into the left side of the piston is inserted into a slot along the length of the sub-bulb so that a pin perpendicular to the axial direction of the piston is inserted into the spool, so that the spool does not rotate inside the piston. The piston reciprocates left and right along the length direction of the long hole, and the piston and the spool move left and right within the sliding surface between the piston and the spool, and the hydraulic oil from the hydraulic pump side port of the body. And a pressure oil discharge circuit that closes the pressure oil supply circuit from the hydraulic pump side boat and allows the pressure oil in the spool to escape to the tank side port of the body. Preferably.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of a vibration compaction machine according to the present invention will be described with reference to an embodiment shown in the drawings. As shown in FIG. It basically comprises a forward / backward operating device 20 provided with a hydraulic servo valve mechanism for operating the forward / backward switching shaft 12 of the device 1.

The vibrating device 1 has a drive shaft 3 to which rotation is transmitted from an engine (not shown) via a pulley 2, and a driven shaft 4 arranged in parallel with the drive shaft 3.
An eccentric pendulum 5 is fixed on the driven shaft 4, and a similar eccentric pendulum 6 is mounted on the driven shaft 4 so as to be able to change the phase with respect to the drive shaft eccentric pendulum 5.

A driven gear 7 is provided at the center of the driven shaft 4 so as to be rotatable with respect to the shaft 4 and not to be movable in the axial direction. The rotation is transmitted from a drive gear 8 fixed to the center of the motor. The driven gear 7 is provided with a spiral groove 10 that is inclined with respect to the axis of the boss 9 on the inner wall of the boss 9.

On the other hand, the driven shaft 4 has a cylindrical shape,
In the portion where the driven gear 7 is located, elongated holes 11 are respectively formed along opposing shaft walls along the axial direction.
A forward / reverse switching shaft 12 is inserted into the driven shaft 4 so as to be rotatable and movable in the axial direction.

The forward / reverse switching shaft 12 has a large-diameter portion 13 that slides on the inner diameter of the driven shaft 4 and a small-diameter portion 14 protruding from one end of the large-diameter portion 13. A piston 15 is provided at the tip of the part 14 via a bearing 16,
The piston 15 is inserted into a hydraulic cylinder 18 provided at one end of an exciter case 17 located on the axis of the driven shaft 4.

Further, a pin 19 is embedded in the large-diameter portion 13 of the forward / reverse switching shaft 12 so as to be orthogonal to the axial direction of the switching shaft 12. It penetrates the hole 11 and engages in the spiral groove 10 in the inner wall of the driven shaft 4.

A piston 15 at one end of the forward / reverse switching shaft 12
In a state in which no external hydraulic pressure acts on the hydraulic cylinder 18 in which the driven gear 7 is inserted, when the rotation from the driving gear 8 is transmitted to the driven gear 7, the forward / reverse switching shaft 12
The lead angle of the spiral groove 10, the lead angle direction, and the driven angle are determined by the fact that both ends of the pin 19 pass through the elongated hole 11 of the driven shaft 4 and engage in the spiral groove 10 on the inner wall of the driven shaft 4. A mechanical return force that is pushed rightward in FIG. 1 is applied along with the rotation direction of the gear 7. The state in which the forward / reverse switching shaft 12 has moved to the rightmost side in the drawing corresponds to the phase in which the eccentric pendulum 6 of the driven shaft 4 moves forward or backward with respect to the eccentric pendulum 5 of the drive shaft 3, for example, at the fastest traveling speed. This means that it has rotated to the position.

On the other hand, a hydraulic cylinder 18 into which a piston 15 at one end of the forward / reverse switching shaft 12 is inserted is connected to one end of the forward / backward operating device 20 provided outside. As shown in FIG. 2, the forward / reverse operating device 20 is configured such that the forward / reverse switching shaft 12 in the driven shaft 4 is connected to the spiral groove 10 of the driven gear 7.
To receive a mechanical return force in the right direction,
Utilizing pressure oil sent from an external hydraulic pump circuit 25, a force that resists the mechanical return force is applied to the hydraulic cylinder 18 or forward / reverse switching is performed by overcoming the mechanical return force. Axis 12 opposite left side of FIG. 1 (reverse)
Exhibits the function of pushing back in the direction.

The forward / reverse operating device 20 is shown in FIGS.
As shown in the figure, one end of the hydraulic cylinder 1
Body 21 having a flow path 22 connected to the motor 8 and a spool 29 protruding from the other end to be connected to the forward / reverse operation lever 23.
And a hydraulic pump circuit 25 connected to the outside of the body 21, and the spool 2 provided in the body 21.
9 and a piston 28 inserted therein.

As shown in FIG. 2, both ends of the body 21 are connected to a rear plug 26 having the flow path 22 at the right end.
It is closed by a front plug 27 inserted through a spool 29 connected to the forward / reverse operation lever 23 at the left end. The piston 28 is inserted into the body 21 and a left portion 28a of the piston 28 One end of the spool 29 is slidably inserted into an insertion hole 37 provided inside the body 21. A center portion of the body 21 is provided with the inside of the body 21 and the hydraulic pump circuit 25. , A pump-side port 30 and a tank-side port 31 are provided.

The piston 28 is always provided with a force to be pushed to the left in the drawing by a spring 32 interposed between the right end thereof and the body rear plug 26, and is provided at the right end along the axial direction. A hole 33 is provided, and a vertical tube 35 having flow paths 34 a and 34 b orthogonal to the axial direction of the piston 28 is inserted into the long hole 33, and the upper end of the vertical tube 35 is connected to the tank of the hydraulic pump circuit 25. By being fixed in the body 21 so as to be connected to the side port 31, it is inserted so as to move in the left-right direction along the length direction of the long hole 33 without rotating in the body 21.

Further, as shown in FIG.
The outer peripheral surface of the left portion 28a bordering on the long hole 33 is connected to a pump-side port 30 of the hydraulic pump circuit 25 so as to receive pressure oil sent from the hydraulic pump 36 through the port 30. A flow path 39 for introducing pressure oil in the concave flow path 38 toward the outer peripheral surface of the spool 29 on the inside at one end (left end) of the concave flow path 38; A short concave flow path 40 is provided on the inner peripheral surface of the piston 28 at the right end portion slightly spaced from the lower end of the flow hole 39.

Further, a flow hole 45 is formed in the inner back wall 41 adjacent to the long hole 33 located at the right end of the piston left portion 28a.
And an inner diameter capable of fitting a flange portion 29a provided on a left portion of the spool 29 to the left end of the piston left portion 28a.
A concave portion 54 having a depth such that the flange portion 29a can be slightly moved in the left-right direction is provided.

On the other hand, the spool 29 inserted into the insertion hole 37 of the left piston portion 28a has a spring 42 interposed between the right end thereof and the inner wall 41 of the piston 28. It is inserted so as to be always pushed to the left in the insertion hole 37, and a left hole is provided in the left part along the axial direction. The pin 44, which is perpendicular to the axial direction, is inserted through the long hole 43 without falling out of the piston left portion 28a.
It is inserted so as to move in the left-right direction along the length direction.

Therefore, unless the operating lever 23 pushes the spool 29 rightward in the drawing, the spool 29 moves leftward along the length direction of the long hole 43 as shown in FIG. By moving the push rod 24 rightward against the force of the spring 42, the push rod 24 moves rightward along the length of the long hole 43 as shown in FIG.

As shown in FIG. 3, the spool 29
Left and right flow paths 47, 47 are provided inside through a partition 46 provided between the right end provided with the spring 42 and the long hole 43.
And a short concave flow path 49 on the outer peripheral surface of the spool 29 located outside the partition 46 and a short concave flow path on the outer peripheral surface of the spool 29 located outside the left flow path 47. 50 are provided.

Further, between the left and right concave flow paths 49 and 50 on the outer peripheral surface of the spool 29, the short concave flow path 40 on the inner peripheral surface of the left piston portion 28a is provided.
A flow path 51 is provided at a position connecting the left flow path 47 in the spool 29 and a right end of a short concave flow path 50 provided on the outer peripheral surface of the spool 29 located outside the partition wall 46. The concave channel 50 and the spool 28
A flow path 52 is provided at a position where the flow path 52 is connected to the right flow path 48.

Further, the left end of the left flow path 47 in the spool 29 is provided with the piston 28
A flow path 53 is provided to communicate with the outer peripheral surface of the spool 29 located on the left end side of the spool 29.

A valve 54 is provided at the right end of the piston 28 as shown in FIGS. 2, 5, and 6, and the valve 54 is provided with a piston as shown in FIGS. When the spool 28 and the spool 29 move rightward in the body 21, the flow path is closed. However, as shown in FIG. 5, the left end of the piston 28 contacts the inner end of the front plug 27 of the body 21. When the inside of the body 21 is moved to the leftmost side, the flow path is opened by one end contacting the vertical cylinder 35 in the long hole 33.

When the compacting machine having the above structure is used, when the body is to be kept neutral, as shown in FIGS. 2 to 4, the operating lever 23 of the forward / reverse operating device 20 is placed in the neutral position. Hold the position fixed by hand. In this state, as shown in FIGS. 2 and 3, the piston 28 and the spool 29 of the forward / reverse operating device 20 are located at the center of the body 21, and the forward / reverse switching shaft 12 of the vibration generator 1 is also located in the driven shaft 7. Although it is located at the center, the forward / reverse switching shaft 12 receives a mechanical return force in the rightward direction by the spiral groove 10 of the driven gear 7 at that time. When the pressure oil flows into the forward / reverse operating device 20 from the right end flow path 22 of the forward / backward operating device 20 and receives the force of the spring 32, the piston 28
Is received from the position shown in FIG.

When the piston 28 receives the pushing force to the left, the operating lever 23 is held at the neutral position by hand and the position of the spool 29 is fixed, as described above.
Only the piston 28 moves leftward along the elongated hole 43 through which the pin 44 is inserted as shown in FIG.

Then, as shown in FIG. 3, the right end of the concave flow path 49 on the outer peripheral surface of the spool 29 overlaps and is connected to the concave flow path 40 on the inner peripheral surface of the piston 28, so that the pump side port of the hydraulic pump circuit 25 is connected. As shown by an arrow A, the pressure oil fed from the inner peripheral surface of the piston 28 passes from the concave flow path 38 on the outer peripheral surface of the piston 28 through the flow hole 39, and from the concave flow path 49 on the outer peripheral surface of the spool 29 to the inner peripheral surface of the piston 28. Concave channel 40
Flow path 5 on the left side of the partition wall 46 of the spool 29
1 to flow into the left channel 47 of the spool 29,
The pressure oil supply circuit from the hydraulic pump side port 30 is opened.

The pressure oil that has flowed into the left flow path 47 of the spool 29 from the hydraulic pump side port 30 flows from the flow path 53 at the tip of the left flow path 47 into the recess 54 on the left side of the piston 28. The hydraulic fluid is sent to the space between the left end of the piston 28 and the front plug 27, and the amount of pressurized oil gradually increases.
Overcoming the force pushing the piston 28 to the left, which is applied from eight directions, this time, as shown in FIG.
Along the long hole 43 in the right direction of the drawing.

As shown in FIG. 4, the piston 28 is
Is pushed back to the right along, the overlap between the concave flow path 49 on the outer peripheral surface of the spool 29 and the concave flow path 40 on the inner peripheral surface of the piston 28 is separated, so that the hydraulic pump side port 30
The flow of pressurized oil is shut off and the pressurized oil supply circuit is closed, and this time the concave flow path 40 and the concave flow path 50 on the outer peripheral surface of the spool 29 located outside the partition wall 46 overlap and are connected. You.

When the concave flow path 40 on the inner peripheral surface of the piston 28 and the concave flow path 50 on the outer peripheral surface of the spool 29 are connected,
This time, the pressure oil in the left end of the piston 28 and the left flow path 47 and the right flow path 48 in the spool 29 is
A pressure oil discharge circuit is formed which is sent from the flow hole 45 formed in the inner inner wall 41 of the piston 28 to the long hole 33 and the tank side port 31 through the flow paths 34 a and 34 b of the vertical cylinder 35, and the hydraulic pressure is reduced. Since there is no force to push the piston 28 back to the right side, such as pressure oil sent from the pump-side port 30, the piston 28 is connected to the hydraulic cylinder 1 of the vibrating device 1.
Due to the mechanical return force from the eight directions and the force of the right end spring 32, it is again pushed to the left along the long hole 43 as shown in FIG.

As a result, if the operation lever 23 is fixed to the neutral position by hand and the spool 29 is maintained so as not to move, the piston 28 is first extended by the mechanical return force from the hydraulic cylinder 18 direction. By being pushed to the left along the hole 43, the hydraulic pump side port 30
Is opened, the piston 28 is pushed back to the right along the long hole 43 by the hydraulic oil force, so that the circuit of the hydraulic pump side port 30 is closed, and the mechanical return force from the vibration generator 1 is returned. As a result, the neutral position is maintained while automatically repeating the movement of being pushed out to the left.

That is, in this compacting machine, the body weight is 50
0 kg or more, and when the operation lever 23 is operated, even if a strong mechanical return force corresponding to the weight of the machine body is received from the vibration device 1, the mechanical return force is applied. When the piston 28 is pushed to the left, the circuit of the hydraulic pump-side port 30 opens and resists the mechanical return force. Therefore, the force for holding the operation lever 23 by hand is as follows. It is sufficient if the force is only a small force that overcomes the elasticity of the spring 42 with respect to the mechanical return force from the hydraulic pump. At the next moment, the pressure oil from the hydraulic pump side port 30 reduces the mechanical return force from the vibrator 1 direction. Since it is received, it is not necessary to substantially apply a pressing force to the hand of the operation lever 23 during that time. Therefore, the operation lever 23
Each time the piston 28 intermittently moves in the leftward direction due to the mechanical return force from the vibrating device 1, the spool 29 is held by hand so that the spool 29 does not move while feeling the force. The aircraft can be held in the neutral position with a light force.

When the body is to be advanced from neutral, the operation lever 23 shown in FIG. 2 is continuously pushed to the forwardmost position on the left side of the drawing, or at an arbitrary speed setting angle position between neutral and forwardmost. Just keep it.

When the operation lever 23 is continuously pushed from the neutral position to the leftmost forward fastest position, first, the spool 2
As a result, the pressure oil discharge circuit connected to the tank-side port 31 as shown by the arrow B in FIG. It is pushed to the left by the mechanical return force from the direction.

Then, when the piston 28 is pushed to the left, the hydraulic oil supply circuit from the hydraulic pump side port 30 as shown by the arrow A in FIG. Is pushed back to the right once. However, since the spool 29 itself continuously moves to the left by continuously pushing the operating lever 23 to the fastest forward position, the piston 28 is immediately connected to the tank side port 31 indicated by the arrow B at the next moment. As shown in FIG. 5, the piston 28 continuously repeats the short stroke movement to the left and right as shown in FIG.
8 gradually shifts to a position where the left end thereof contacts the front plug 27 of the body 21 to reach the fastest forward state.

When the operating lever 23 is fixed at an arbitrary position while being pushed from the neutral position toward the fastest forward position, the spool 29 is held in the same manner as when the operating lever 23 is held at the neutral position. Is fixed, the piston 28 is pushed to the left by a mechanical return force from the direction of the vibrating device 1, so that the pressure oil supply circuit from the hydraulic pump side port 30 shown by the arrow A in FIG. The piston 28 is once pushed rightward by the pressure oil.

Then, when the piston 28 is pushed rightward, the pressure oil supply circuit from the hydraulic pump side port 30 is closed, and the pressure oil discharge circuit of the tank side port 31 shown by the arrow B in FIG. Since the piston 29 is still fixed, the piston 28 is pushed again to the left by the mechanical return force from the direction of the vibration exciter 1 at that position.
As a result, the pressure oil supply circuit from the hydraulic pump side port 30 shown by the arrow A opens, and as a result, the operation of being pushed to the right again is repeated, and the state in which the body advances at a predetermined speed is maintained.

On the other hand, when the aircraft is to be moved backward, the operation lever 23 shown in FIG. 2 is continuously pushed from the neutral position to the fastest reverse position on the right side of the drawing, or to an arbitrary speed setting angle position between the neutral position and the fastest reverse position. Just keep it.

[0047]
When the operation lever 23 is continuously pushed from the neutral position to the rightmost reverse speed position, first, the spool 29 is pushed rightward in the drawing, so that, as a phenomena, first, as shown by the arrow A in FIG. Then, the pressure oil supply circuit of the hydraulic pump side port 30 is opened, and the next instantaneous piston 28 is pushed back rightward by the inflowing pressure oil. When the piston 28 is pushed back to the right, this time, as shown by the arrow B in FIG.
At the next moment, the pressure oil discharge circuit is opened, and at the next moment, the piston 28 receives the mechanical return force from the direction of the vibrator 1 and tries to be pushed to the left. At this time, the operating lever 23 is pushed in the fastest backward direction. By continuing, the spool 29 continuously moves to the right side, so that the piston 28
The spool 29 is pushed rightward before being pushed leftward due to the mechanical return force from the left direction, and again the arrow A in FIG.
As shown by, the hydraulic oil supply circuit of the hydraulic pump side port 30 is opened, and the piston 28 is pushed back to the right. The piston 28 repeats such a short stroke reciprocating movement to the left and right while the spool 29 The piston 28 is sequentially moved rightward in accordance with the rightward movement, and as shown in FIG.
The inner inner wall 4l adjacent to the long hole 33 of 8a gradually shifts to a position where it comes into contact with the vertical cylinder 35 inserted into the long hole 33, and reaches the fastest reverse state.

When the operation lever 23 is fixed at an arbitrary position while being pushed from the neutral position toward the fastest reverse position, the spool 29 is held in the same manner as when the operation lever 23 is held at the neutral position. Is fixed, the piston 28 is pushed leftward by a mechanical return force from the direction of the vibrating device 1, so that the pressure oil supply circuit from the hydraulic pump side port 30 as shown by the arrow A in FIG. Open and push the piston 28 back to the right once with the pressure oil.

Then, when the piston 28 is pushed rightward, the pressure oil supply circuit from the hydraulic pump side boat 30 is closed, and the pressure oil discharge circuit of the tank side port 31 shown by the arrow B in FIG. Since the piston 29 is still fixed, the piston 28 is pushed again to the left by the mechanical return force from the direction of the vibration exciter 1 at that position.
As a result, the pressure oil supply circuit from the hydraulic pump side port 30 shown by the arrow A opens, and as a result, the operation of being pushed to the right again is repeated, and the state in which the body moves backward at the predetermined speed is maintained.

[0051]

As described above, in the compacting machine according to the present invention, the hydraulic pressure against the mechanical return force generated by the rotation of the eccentric pendulum in the vibration generating device is set in the cylindrical body in the vibration generating device side. And a spool interlocking with an operation lever slidably inserted into the other end of the piston. The body is disposed between the spool and the piston. A forward-reverse operating device equipped with a servo valve mechanism for supplying pressure oil sent from an external hydraulic pump to the other end of the piston as a pressure against the mechanical return force from the vibrating device is provided. Is a compacting machine of 500kg or more,
By sending pressure oil to which pressure is applied by a hydraulic pump from the forward / reverse operating device to the hydraulic cylinder of the vibration generator,
It is possible to provide an airframe capable of controlling the operation speed at a desired speed at any position in forward and backward traveling by holding the operation lever at the operated position with a light operation force for switching the operation lever.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a configuration of a vibrating device in a vibration compaction machine of the present invention.

FIG. 2 is a cross-sectional view showing a configuration of a forward and backward operation device in the vibration compaction machine of the present invention.

FIG. 3 is a cross-sectional view of a state in which a hydraulic pump side circuit is open when the forward / reverse operating device is in a neutral position.

FIG. 4 is a sectional view showing a state where the tank side circuit is open.

FIG. 5 is a cross-sectional view showing a state in which the forward-reverse operation device is at the maximum forward speed.

FIG. 6 is a cross-sectional view showing a state at the time of the maximum reverse speed of the forward / reverse operating device.

FIG. 7 is a hydraulic circuit diagram of the forward / reverse operating device.

[Explanation of symbols]

1: Exciter, 2: Pulley, 3: Drive shaft,
4: driven shaft, 5, 6: eccentric pendulum, 7: driven gear,
8: drive gear, 9: boss, 10: spiral groove, 11:
Long hole, 12: forward and backward switching shaft, 13: large diameter part, 1
4: Small diameter part, 15: Piston, 16: Bearing,
17: Exciter case, 18: Hydraulic cylinder, 1
9: pin, 20: forward and backward operation device, 21: body,
22: flow path, 23: operation lever, 25: hydraulic pump circuit, 26: rear plug, 27: front plug,
28: Piston, 29: Spool, 30: Hydraulic pump side port, 31: Tank side port, 32: Spring, 33: Slot, 34a, 34b: Flow path, 3
5: vertical cylinder, 36: hydraulic pump, 37: insertion hole, 3
8: concave channel, 39: channel, 40: concave channel, 4
1: Inner wall, 42: Spring, 43: Slot, 4
4: Pin, 45: Flow hole, 46: Partition wall, 47, 4
8: channel, 49, 50: concave channel, 51, 52, 5
3: flow path, 54: valve,

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-286306 (JP, A) JP-A-6-33413 (JP, A) JP-A-63-60306 (JP, A) 17323 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) E01C 19/22 E01C 19/34 E02D 3/046 B06B 1/16

Claims (3)

(57) [Claims] 1. An eccentric pendulum for changing the phase of rotation with respect to an eccentric pendulum on the other axis is provided on one of the linked parallel axes, and the phase of the eccentric pendulum is changed in the axis of the eccentric pendulum. Slidably inserted through the forward / backward switching shaft for rotation, and one end of the forward / backward switching shaft on the axis of the forward / backward switching shaft is hydraulically opposed to a mechanical return force generated by the rotation of the eccentric pendulum. In a vibration compaction machine equipped with a vibrating device having a hydraulic cylinder for switching the rotation of a pendulum in a forward and backward direction by moving the pendulum in an axial direction, a cylinder body is used as a forward and backward operating device connected to the hydraulic cylinder. A piston which receives a mechanical return force applied from the direction of the forward / reverse switching shaft at one end thereof, and a spool which is interlocked with an operation lever slidably inserted into the other end of the piston. A servo that supplies pressure oil sent from a hydraulic pump outside the body between the spool and the piston to the other end of the piston as a pressure opposing a mechanical return force from the forward / reverse switching axial direction. A forward-backward operation mechanism for a vibration compaction machine, comprising a valve mechanism. 2. A vertical cylinder which is slidably inserted into a body, and a vertical cylinder which is orthogonal to a body axis direction connected to a tank side port of the body is inserted into an elongated hole along the length direction of the piston. As a result, the spool reciprocates left and right without rotating in the body, and the spool interlocked with an operation lever outside the body is slidably inserted into the left side of the long hole of the piston. A forward / backward operation mechanism for the vibration compaction machine according to claim 1. 3. A spool inserted into the left side of the piston without rotating in the piston by inserting a pin perpendicular to the axial direction of the piston into an elongated hole along the length of the spool. The piston reciprocates left and right along the length direction of the long hole, and the piston and the spool move left and right within the sliding surface between the piston and the spool, and the hydraulic oil from the hydraulic pump side port of the body. And a pressure oil discharge circuit that closes the pressure oil supply circuit from the hydraulic pump side port and allows the pressure oil in the spool to escape to the tank side port of the body. The forward / backward operation mechanism of the vibration compacting machine according to claim 1 or 2.