JPH0675738B2 - Spool valve device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a spool valve device used in a hydraulic actuator.

(Prior Art) A hoop wrench is usually used in the work of bending the end portions of the hoops and stalaps in reinforced concrete construction.

The conventional hoop wrench has a structure in which a winding bar bending arm is attached to the tip of the piston rod of the hydraulic cylinder, and this arm is rocked by feeding pressure oil to the hydraulic cylinder to perform the bending operation. ing.

After the bending operation is performed, the pressure oil in the hydraulic cylinder is drained and the piston rod is moved backward.

(Problems to be Solved by the Invention) However, since the above-mentioned work for draining pressure oil is performed using a manual pressure reducing valve, the operation is complicated and
This is a cause of lowering work efficiency.

The present invention has been made in consideration of such points,
An object of the present invention is to provide a spool valve device capable of facilitating the handling of a hydraulic operating device and improving work efficiency.

[Structure of Invention]

(Means for Solving the Problem) In order to achieve the above-mentioned object, the present invention is a spool valve device arranged in a hydraulic operating device, in which a cylinder chamber of the hydraulic operating device and an oil tank are connected to the front. A cylindrical cylinder having a valve seat formed in the middle of the passage, and a passage communicating with one pump mechanism of the plurality of pump mechanisms of the hydraulic actuator is opened in the rear, and the valve seat at the tip. A valve body that engages is formed, and a spool that is slidably arranged in the axial direction in the cylindrical cylinder with a minute gap between the cylindrical cylinder and the inner wall of the cylindrical cylinder; And a spring arranged between them.

(Operation) According to the spool valve device of the present invention, when the work required by the hydraulic actuator is completed and the operation of the pump mechanism is stopped, the cylinder chamber of the hydraulic actuator and the oil tank are automatically communicated with each other, and the cylinder chamber is closed. Pressure oil is returned to the oil tank. That is, by stopping the operation of the pump mechanism, the supply of pressure oil is stopped, the spool is pushed back by the force of the spring,
By releasing the engagement between the spool valve element and the valve seat,
The cylinder chamber and the oil tank are automatically connected.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side sectional view of a hoop wrench provided with a spool valve device according to the present invention, and FIG. 2 is a view showing a tip end portion of the hoop wrench viewed in the direction of arrow A in FIG. In the drawing, reference numeral 11 is an electric motor, which is attached to the casing body 13 with the motor shaft 12 inserted in the casing body 13. An oil tank 14 for storing oil is provided inside the casing body 13, and a pump mechanism 15 for pumping the oil in the oil tank 14 is further provided. Pump mechanism
Reference numeral 15 denotes a cam portion 16 formed at the tip of the motor shaft 12, a piston 17 reciprocated by the cam portion 16 via a needle bearing, and an opening / closing valve 18 disposed in an oil passage.
The on-off valve 18 normally closes the oil passage with a spring 19. Casing body 13
A cylinder chamber 20 is formed substantially at the center of the cylinder chamber 20, and the cylinder chamber 20 and the oil tank 14 are separated by a vertical wall 21. A plurality of (for example, three) pump mechanisms 15 are provided, and one pump mechanism 15 (indicated by an upper position in FIG. 1) is excluded, and the other pump mechanism 15a (indicated by a chain line below in FIG. 1) An oil supply passage 22 for supplying the pressure oil of 2 passes through the vertical wall 21 and communicates with the cylinder chamber 20. The cylinder chamber 20 and the oil tank 14
A communication passage 23 is provided so as to penetrate through the vertical wall 21, and a spool valve device 24 is arranged in the communication passage 23. The spool valve device 24 serves to open and close the communication passage 23, and a small gap (for example, between the cylindrical cylinder 25 formed in the vertical wall 21 and the cylindrical cylinder inner wall in the cylindrical cylinder 25). Spool 26 that is slidable in the axial direction with a 0.1 mm diameter gap), and spool 26
And a spring 27 arranged in the cylindrical cylinder 25 so as to abut the tip end of the. Cylindrical cylinder 25
Has a valve seat 28 formed in the middle of a communication passage 23 that connects the cylinder chamber 20 and the oil tank 14 at the front position, and communicates with one pump mechanism 15 of the plurality of pump mechanisms at the rear side. The passage 29 is opened. Also, at the tip of the spool 26,
A valve body 30 that opens and closes a valve seat 28 in the cylindrical cylinder 25 is formed. When the pump mechanism 15 does not operate, the spool 26 has its rear end stopped by the spring 27.
Is pushed up until it touches. Oil tank on the vertical wall 21
14 and the front end of the cylinder chamber 20 (the end opposite the vertical wall 21)
An oil return path 32 that communicates with
32 is branched in the middle to a pressure buffer chamber 34 in which an air bag 33 is arranged. The pressure buffer chamber 34 is the handle of the hoop wrench.
Formed within 35. Further, a release hole 36 communicating with the pressure buffer chamber 34 is formed at an appropriate position on the front end side with respect to the middle of the cylinder chamber 20.

A piston flange 37 is disposed in the cylinder chamber 20 so as to be slidable in the axial direction, and a piston rod 38 is joined to the rear surface of the piston flange 37. Piston rod 38
Is the front part of the casing body 13 that seals the cylinder chamber 20.
A semicircular groove 39 is formed at the tip of the protrusion 13a through the casing 13a to the outside of the casing body. A piston flange return spring 40 is arranged between the rear surface of the piston flange 37 and the front portion 13a of the casing body 13.

At the tip of the front portion 13a of the casing body 13, the center portion of the winding bar bending arm 41 is swingably supported on a shaft 42 fixed in a direction orthogonal to the axis of the piston rod 38. The bending arm 41 has a presser claw 43 for bending the winding bar H at the tip, and a connecting pin 44 rotatably inserted in the groove 39 at the tip of the piston rod 38 at the rear end. . At the front end of the front portion 13a of the casing body 13 and at a position facing the arm 41, the main bar receiving portion 45 is provided.
Is installed. As shown in FIG. 2, the main bar receiving portions 45 are attached in a pair on the left and right with the arm 41 in between, and have main bar receiving surfaces 45 a facing the arms 41. The main bar receiving portion 45 receives the main bar S when winding the curl bar H around the main bar S, and the front bar 13a of the casing body 13 is provided.
Are fixed to both side surfaces of the with bolts 46.

Next, the operation of this embodiment having such a configuration will be described.

First, the end portion of the curl bar H to be wound around the main bar S is arranged so as to abut at a predetermined position from the direction perpendicular to the main bar S, and the main bar receiving surface 45a of the hoop wrench is attached to the main bar S and the curl bar H.
The arm 41 is arranged so as to sandwich the winding bar H between the main bar S and the main bar receiving surface 45a (see FIG. 1). After setting the hoop wrench on the main bar S and the curl bar H in this manner, the switch 11a of the electric motor 11 of the hoop wrench is turned on. By driving the electric motor 11, the motor shaft 12 is driven to rotate, and the cam 16 also rotates. As a result, the piston 17 is reciprocated, and the inside of the oil in the oil tank 14 is suction-compressed to generate pressure oil. The pressure oil generated by the pump mechanism 15 pushes up the on-off valve 18 against the spring 19 and the passage 29
The pressure oil generated by the other pump mechanism 15a is pressure-fed into the cylinder chamber 20 through the oil supply passage 22 while being pressure-fed to the spool valve device 24 through the oil supply passage 22. Spool valve device 24
The pressure oil pressure-fed to the cylinder 26 is fed from the rear of the cylindrical cylinder 25 and pushes the spool 26 forward against the spring 27.
When the spool 26 moves forward, the valve element 30 at the tip is a cylindrical cylinder.
25 insert-engages with a valve seat 28 to close the opening of the valve seat 28. As a result, the communication passage 23 that connects the oil tank 14 and the cylinder chamber 20 is closed and closed. Subsequently, the pressure oil pumped from the pump mechanism 15 into the cylindrical cylinder 25 flows through the gap between the spool 26 and the inner diameter of the cylindrical cylinder 25, and is returned to the oil tank 14 through the communication passage 23. This allows the spool valve device 24
Keeps the communication passage 23 between the oil tank 14 and the cylinder chamber 20 closed and blocked.

The pressure oil sent to the cylinder chamber 20 is
It acts on the flange surface of 37 and moves the piston flange 37 and the piston rod 38 to the left in FIG. 1 against the return spring 40. As a result, the connecting pin 44 at the rear end of the arm 41 is pushed to the left in FIG.
Swing toward 45. By the swing of the arm 41, the end portion of the curl bar H is bent as shown by the reference numeral H ′ in FIG. 1 and wound around the main bar S.

During this winding work, the arm 41 swings too much and
When the piston flange 37 passes the position of the release hole 36 so as not to wind the cylinder more than necessary, the pressure oil in the cylinder chamber 20 returns to the pressure buffer chamber 34, the oil tank 14 through the release hole 36, and the piston flange 37 and the piston rod 37 Stop 38 further advances.

When the forward movement of the piston rod 38 is stopped and the winding operation by the arm 41 is completed, the switch 11a is turned off to stop the operation of the electric motor 11. As a result, the supply of pressure oil from the pump mechanism 15 is stopped, and the spool of the spool valve device 24 is
26 is pushed back by the spring 27, and the engagement between the valve element 30 and the valve seat 28 is released. The cylinder chamber 20 and the oil tank 14 are communicated again by the communication passage 23, the pressure oil in the cylinder chamber 20 is returned to the oil tank 14, and the piston flange 37 is pushed back by the return spring 40 to the right in FIG. As a result, the tip of the arm 41 is swung to the left in FIG. 1, the holding claw 43 at the tip is separated from the curl bar H, and the hoop wrench is removed from the assembly position of the main bar S and the curl bar H.

In the description of the present embodiment, an example in which the hydraulic actuating device is used for a hoop wrench is shown, but the hydraulic actuating device to which the spool valve device according to the present invention is applied is not limited to this, and for example, a hydraulic actuating cutter, a puncher. Various application examples are possible.

〔The invention's effect〕

As described above, according to the present invention, the spool valve device is arranged between the cylinder chamber and the oil tank of the hydraulic operating device, and the communication passage that connects the cylinder chamber and the oil tank can be automatically shut off and opened. Therefore, the operation of the hydraulic actuator such as the swinging of the arm for bending the winding bar is controlled by the switch of the electric motor.
It can be done automatically just by turning it on and off, improving work efficiency.

[Brief description of drawings]

FIG. 1 is a side sectional view of a hoop wrench provided with a spool valve device according to the present invention, and FIG. 2 is a view showing a tip portion of the hoop wrench viewed from the direction of arrow A in FIG. 11 …… electric motor, 14 …… oil tank, 15,15a …… pump mechanism, 20 …… cylinder chamber, 22,29 …… oil passage, 23 …… communication passage, 25 …… cylindrical cylinder, 26 …… spool, 27 …… Spring, 28 …… Valve seat, 30 …… Valve element, 36 …… Release hole,
37 …… Piston flange, 38 …… Piston rod, 40…
… Return spring, 41 …… arm.

Claims (1)

[Claims] 1. A valve seat formed in the middle of a passage that connects a cylinder chamber of an oil pressure operating device and an oil tank to the front, and one pump mechanism of a plurality of pump mechanisms of the oil pressure operating device to the rear. A cylindrical cylinder having a communicating passage open;
A spool having a valve body formed at its tip end that engages with the valve seat, and arranged in the cylindrical cylinder so as to be slidable in the axial direction with a minute gap between the cylindrical cylinder and the inner wall of the cylindrical cylinder; And a spring disposed between the spool and a tip of the spool.