JP2015078740A - Change-over valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a change-over valve in which the risk of leaking fluid out of the change-over valve is reduced when the change-over operation is carried out.SOLUTION: This invention is constituted as follows. When a solenoid 26 is not excited, a check valve fitting hole 42 and a rod fitting hole 50 at an automatic operation side are shut off against communication by a valve seat 46. A third passage 38 is communicated with a hydraulic chamber 56, oil from a hydraulic source is not supplied to a cylinder, but a rod 48 at an automatic operation side is moved toward a second cover 20 side when the solenoid is excited, a check valve 16 is moved toward the second cover side against a pressing force of a second resilient member 24, the shut-off communication between the check valve fitting hole and the rod fitting hole at the automatic operation side by the valve seat is released, a first passage 30 is communicated with the hydraulic chamber 56, a spool 14 is moved toward the second cover side against the pushing force of a first resilient member 22, the first passage and a second passage 34 are communicated to each other and oil from the hydraulic source is supplied to the cylinder.

Description

  The present invention relates to a pilot-type switching valve using fluid pressure for supplying hydraulic pressure.

  As shown in FIG. 5, a direct-acting switching valve is conventionally known. The switching valve 100 has the same mechanism as the switching valve of the present invention, but the type is a spool 114 (having valve seats 146, 146 'on both sides by the suction force of the solenoid 126 and the force of the spring 124 provided on the opposite side. The piston is actuated directly in the figure. That is, when the solenoid 126 is energized, the spool 114 moves to the left in the figure, the right valve seat 146 is opened, the left valve seat 146 'is closed, and the hydraulic pressure in the hydraulic source side passage 128 flows from the hydraulic source side passage 128. Enter the cylinder side passage 132. When not energized, the spring 114 force moves the spool 114 (piston) to the right, the right valve seat 146 is closed, the left valve seat 146 'is opened, and the cylinder side passage 132 is electrically connected to the oil tank side passage 136. This switching valve 100 is provided in each cylinder-side passage 132, and oil in the hydraulic-source-side passage 128 enters the cylinder-side passage 132 on the solenoid 126 side that is energized, so that the valves 146, 146 'opens and closes. The energized solenoid 126 is de-energized after confirmation by the limit switch after the cylinder side passage 132 is actuated. That is, the energization is performed only when the actuator is operated, and the standby is not performed.

  However, when the switching valve 100 is energized and de-energized, the spool 114 (piston) is in an intermediate open state, and the hydraulic source side passage 128 is electrically connected to the cylinder side passage 132 and the oil tank side passage 136 to be connected to the valve seat 146. Since 146 ′ is large, the hydraulic source side passage 128 is lost. In order to prevent this, if the force of the spring 124 is increased so as to operate quickly, the solenoid 126 must be increased in force, which makes it difficult to design the solenoid 126. In addition, if a pilot spool is used to operate a linear spool, the usable solenoid suction force is small and the diameter of the automatic operation side rod is small. The dimensions need to be the same length as the spool, and in order to switch to the first passage, the second passage, and the third passage, it is necessary to process a narrower portion and an O-ring groove. . Moreover, it is difficult to produce a pilot spool without bending. If there is a bend, it will cause inoperability. Further, when switching is performed, there is a risk that fluid may leak from the switching valve. Further, when the left and right sealing sheets are opposite to each other as in the spool of the conventional example (see FIG. 5), the one-side sheet is always open, and both sheets are opened during operation, so that oil flows out to the tank. . To prevent this, it is necessary to increase the spring force and speed up the spool operation. However, if the spring force is increased, it becomes necessary to increase the suction force of the solenoid. Since this has a limit, the conventional switching valve cannot eliminate the leakage to the tank.

In order to solve the above-described problems, in the invention according to claim 1, a pilot-type switching valve using fluid pressure for supplying hydraulic pressure, comprising a main body, a spool, a check valve, and a first cover In the switching valve having the second cover, the first elastic member, the second elastic member, and the solenoid, the main body communicates with the first passage communicating with the hydraulic pressure source, the second passage communicating with the cylinder, and the oil tank. A third passage that crosses the first passage, the second passage, and the third passage, and a spool fitting hole that slides the spool, and a check that slides the check valve across the first passage. A valve fitting hole, a check valve fitting hole that intersects the first passage and the check valve slides, and a third conduction port that intersects the third passage, Automatic operation side at the valve seat and one end through the valve seat And the first cover communicates with one end of the check valve fitting hole, the automatic operation side rod fitting hole in which the automatic operation side rod of the check valve slides, and the third conduction A fourth conduction port communicating with the mouth, a fifth conduction port intersecting both the fourth conduction port and the automatic operation side rod fitting hole, a hydraulic chamber communicating with the spool fitting hole, and the automatic operation A first conduction port that intersects the side rod fitting hole, and a second conduction port that intersects the first conduction port and communicates with the hydraulic chamber, wherein the solenoid is the main body of the first cover. The spool is provided so as to slide on the automatic operation side rod, and the spool is formed by the first elastic member disposed between the main body and the second cover. The check valve is a second elastic member disposed on the main body. When the solenoid is not excited, the check valve fitting hole and the automatic operation side rod fitting hole are disconnected from each other by the valve seat when the solenoid is not excited. 3 passages communicate with the third conduction port, the fourth conduction port, the fifth conduction port, the automatic rod fitting hole, the first conduction port, the second conduction port, and the hydraulic chamber, Oil from the hydraulic pressure source is not supplied to the cylinder, and the automatic operation side rod moves to the second cover side when the solenoid is energized, so that the check valve is pressed by the second elastic member. The first passage is moved to the second cover side, the communication block between the check valve fitting hole by the valve seat and the automatic operation side rod fitting hole is released, and the first passage is The check valve fitting hole, the automatic side rod fitting hole, the first By communicating with the conduction port, the second conduction port and the hydraulic chamber, the spool moves to the second cover side against the pressing force of the first elastic member by the oil from the hydraulic source, The first passage communicates with the second passage and is configured to supply oil from a hydraulic pressure source to the cylinder.

  Furthermore, in the invention according to claim 2, two O-rings are arranged on the automatic operation side rod, and when the solenoid is in the non-excited state, the two solenoids are closer to the solenoid than the fifth conduction port. When the O-ring is arranged and the solenoid is energized, the two O-rings sandwich the fifth conduction port so that the fifth conduction port and the automatic operation side rod fitting hole do not communicate with each other. It is characterized by being arranged respectively.

  In the invention according to claim 3, the spool includes a first sheet and a second sheet, and when the solenoid is in a non-excited state, the first sheet is inserted into the third passage and the spool fitting. Although the communication of the joint hole is not blocked, the second sheet blocks the communication of the first passage and the spool fitting hole, and when the solenoid is energized, the first sheet moves to the third passage. And the communication between the spool fitting hole is cut off, but the second sheet is configured not to cut off the communication between the first passage and the spool fitting hole.

  Furthermore, in the invention which concerns on Claim 4, the said main body has a manual operation side rod fitting hole, The said check valve has a manual operation side rod in the other end part, The said manual operation side rod is the said manual operation side. The operation side rod fitting hole slides and protrudes from the main body to the outside.

  Moreover, in the invention which concerns on Claim 5, the diameter of the rod of the position which has the two said O rings of the said automatic operation side rod is smaller than the diameter of the rod from the vicinity of the position to the valve seat of the said check valve It is characterized by that.

  Further, the invention according to claim 6 is characterized in that an oil groove is provided in a part of the check valve along a sliding direction of the check valve.

  According to the first aspect of the present invention, if the automatic operation side rod and the valve seat seal portion have substantially the same diameter, even if a portion thinner than the automatic operation side rod fitting hole diameter is provided, the length is short and there is no seal portion. Therefore, processing is easy. Even if the diameter of the check valve is large, if the diameter of the rod on the manual operation side is the same as the diameter of the check valve and valve seat seal, the check valve maintains the balance between the automatic side and the manual side with hydraulic pressure. Therefore, it is sufficient to balance the attraction force of the solenoid only with the force of the second elastic member. Thereby, the force (repulsive force) of the second elastic member can be reduced. Therefore, since the check valve can take a long fitting part with the main body, sufficient safety can be obtained in operation. Further, since the diameter can be increased, a plurality of oil grooves serving as oil passages can be provided in the periphery, and the oil passage area can be sufficiently secured. Further, since the spool is not operated by the suction force of the solenoid but is operated by the hydraulic pressure entering the hydraulic chamber, the diameter and the stroke can be freely set, and the flow paths to the first passage, the second passage, and the third passage. Since the spool has a large diameter, there is no problem in processing even if it is thin.

  According to the second aspect of the present invention, of the two O-rings, the O-ring on the valve seat side returns the oil tank from the hydraulic chamber to the hydraulic chamber when energized and returns from the hydraulic chamber to the hydraulic chamber when not energized. It becomes a seal that changes. The O-ring on the side away from the valve seat is not necessary for the type that requires oil in the solenoid, and is required for the type that does not require oil, and can be applied to any type of solenoid.

  According to the invention of claim 3, the spool uses a high-pressure hydraulic source hydraulic pressure for its operation, and the pressure receiving diameter can be increased, and the seal is performed at the fitting portion, and the diameter of the spool when the flow path is opened. Can be thinned to have a sufficient diameter of the flow path. Further, the first elastic member does not need to be adjusted to the load entering the hydraulic chamber, and it is sufficient if there is a force for operating the spool. Furthermore, oil can be prevented from flowing into the tank. Further, the first sheet and the second sheet are not opened at the same time, and the necessary side is opened after both sheets are sealed. And since the spool diameter can be increased, the operating speed is fast and does not leak when switching.

  According to the invention of claim 4, if the manual operation side rod is provided on the opposite side of the solenoid, and the rod diameter is the same or substantially the same as the automatic operation side rod, the hydraulic check valve is in a balanced state. Thus, the second elastic member can be designed in an optimum state with respect to the solenoid. Even if the diameter of the check valve is large, if the diameter of the manually operated rod is the same as the diameter of the check valve and valve seat seal, the hydraulic pressure between the automatic operation side rod side and the manual operation side rod side of the check valve Therefore, it is sufficient to balance the attraction force of the solenoid only with the force of the second elastic member. Thereby, the force (repulsive force) of the second elastic member can be reduced.

  According to the invention which concerns on Claim 5, since it is possible to make the space between an automatic operation side rod, a check valve, and a valve seat into the minimum dimension by adoption of a check valve system, the diameter of a check valve is made into the automatic operation side rod. It is possible to make the diameter thinner than the diameter.

  According to the invention which concerns on Claim 6, it becomes possible to provide the oil groove which has multiple and sufficient flow paths in the circumference | surroundings by enabling the diameter of the stable check valve. Further, since the diameter can be increased, a plurality of oil grooves serving as oil passages can be provided in the periphery, and the oil passage area can be sufficiently secured.

It is a figure which shows sectional drawing of the switching valve when the solenoid of one Example of this invention is not excited. It is a figure which shows sectional drawing of the switching valve when the solenoid of one Example of this invention is excited. It is a figure which shows the check valve and manual operation side rod of one Example of this invention. It is a system diagram when the switching valve of the present invention is mounted on an electrohydraulic operating device. It is a figure which shows the partial cross section figure of the direct-acting switching valve of a prior art.

  Other objects, features and advantages of the present invention will become apparent from the following description of embodiments of the present invention with reference to the accompanying drawings.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Corresponding components are denoted by common reference symbols throughout the drawings.

  Referring to FIGS. 1 and 2, a pilot-type switching valve 10 using fluid pressure for supplying hydraulic pressure includes a main body 12, a spool 14, a check valve 16, a first cover 18, and a second cover. 20, a first elastic member 22, a second elastic member 24, and a solenoid 26. First, the main body 12 includes a first passage 30 communicating with the hydraulic source side passage 28, a second passage 34 communicating with the cylinder side passage 32, a third passage 38 communicating with the oil tank side passage 36, and a first passage. 30, a spool fitting hole 40 that intersects the second passage 34 and the third passage 38, and the spool 14 slides, and a check valve fitting hole 42 that intersects the first passage 30 and the check valve 16 slides. The check valve fitting hole 42 intersects with the first passage 30 and the check valve 16 slides, and the third conduction port 44 intersects with the third passage 38. Next, the check valve 16 has a valve seat 46 and an automatic operation side rod 48 at one end portion through the valve seat 46. Further, the first cover 18 communicates with one end of the check valve fitting hole 42, the automatic operation side rod fitting hole 50 in which the automatic operation side rod 48 of the check valve 16 slides, and the third conduction port 44. A fourth conduction port 52 that communicates, a fifth conduction port 54 that intersects both the fourth conduction port 52 and the automatic operation side rod fitting hole 50, a hydraulic chamber 56 that communicates with the spool fitting hole 40, and automatic operation It has a first conduction port 58 that intersects the side rod fitting hole 50 and a second conduction port 60 that intersects the first conduction port 58 and communicates with the hydraulic chamber 56. The hydraulic chamber 56 does not have to be a concave chamber as shown in FIG. 1, and only the O-ring may be provided. The solenoid 26 is provided on the side opposite to the main body 12 of the first cover 18 so as to slide the automatic operation side rod 48, and the spool 14 is interposed between the main body 12 and the second cover 20. The first elastic member 22 arranged is pressed against the first cover 18, and the check valve 16 is pushed against the first cover 18 by the second elastic member 24 arranged on the main body 12.

  When the solenoid 26 is not excited, communication between the check valve fitting hole 42 and the automatic operation side rod fitting hole 50 is blocked by the valve seat 46, and the third passage 38 is connected to the third conduction port 44. , The fourth conduction port 52, the fifth conduction port 54, the automatic operation side rod fitting hole 50, the first conduction port 58, the second conduction port 60, and the hydraulic chamber 56, and the oil from the hydraulic source side passage 28. Is not supplied to the cylinder side passage 32.

  When the solenoid 26 is energized, the automatic operation side rod 48 moves to the second cover 20 side, so that the check valve 16 moves to the second cover 20 side against the pressing force of the second elastic member 24. The communication between the check valve fitting hole 42 by the valve seat 46 and the automatic operation side rod fitting hole 50 is released, and the first passage 30 is connected to the check valve fitting hole 42 and the automatic operation side rod fitting. The spool 14 communicates with the joint hole 48, the first conduction port 58, the second conduction port 60, and the hydraulic chamber 56, and the spool 14 opposes the pressing force of the first elastic member 22 by the oil from the hydraulic source side passage 28, and the second By moving to the cover 20 side, the first passage 30 communicates with the second passage 34, and the oil from the hydraulic source side passage 28 is supplied to the cylinder side passage 32 and the cylinder side passage 32.

  In order to improve the sealing performance, the fitting portion between the main body 12 and the spool 4 may be sealed using an O-ring or the like.

  As a result, if the automatic operation side rod 48 and the valve seat 46 seal portion have substantially the same diameter, even if a portion thinner than the diameter of the automatic operation side rod fitting hole 50 is provided, the length is short and there is no seal portion. Is easy. Accordingly, since the check valve 16 can be fitted with the main body 12 for a long time, the operation can be sufficiently safe. Further, since the spool 14 is not operated by the suction force of the solenoid 26 but is operated by the hydraulic pressure entered in the hydraulic chamber 56, the diameter and the stroke can be freely set, and the first passage 30, the second passage 34, and the third passage. Since the diameter of the spool 14 is large in the flow path to the passage 38, there is no problem in processing even if it is thin.

  Further, two O-rings 66 and 68 are disposed on the automatic operation side rod 48. When the solenoid 26 is not excited, the two O-rings 66 and 68 are closer to the solenoid 26 side than the fifth conduction port 54. When the solenoid 26 is energized, the two O-rings 66 and 68 are arranged so as to sandwich the fifth conduction port 54 so that the fifth conduction port 54 and the automatic operation side rod fitting hole 50 do not communicate with each other. Has been placed.

  As a result, of the two O-rings 66 and 68, the O-ring 66 on the valve seat 46 side supplies hydraulic pressure from the hydraulic source side passage 28 to the hydraulic chamber 56 when energized, and from the hydraulic chamber 56 to the oil tank side passage when not energized 36 It becomes a seal that changes the return and flow path. The O-ring 68 on the side away from the valve seat 46 is not required in the case where the solenoid 26 requires oil, and is required in the case where the oil does not need oil. is there.

  Furthermore, the spool 14 includes a first sheet 62 and a second sheet 64. When the solenoid 26 is not excited, the first sheet 62 does not block communication between the third passage 38 and the spool fitting hole 40. However, when the second sheet 64 blocks communication between the first passage 30 and the spool fitting hole 40 and the solenoid 26 is energized, the first sheet 62 moves between the third passage 38 and the spool fitting hole 40. Although the communication is blocked, the second sheet 64 is configured not to block the communication between the first passage 30 and the spool fitting hole 40.

  As a result, the spool 14 uses a high-pressure hydraulic source hydraulic pressure for its operation, and the pressure receiving diameter can be increased, and the sealing is performed at the fitting portion. It can be made thinner. Further, the first elastic member 22 does not need to be adjusted to the load that has entered the hydraulic chamber 56, and it is sufficient if there is a force for operating the spool 14. Furthermore, oil can be prevented from flowing out to the oil tank side passage 36. Further, the first sheet 62 and the second sheet 64 are not opened at the same time, and the necessary sheet side is opened after the sheets 62 and 64 are surely sealed. Since the diameter of the spool 14 can be increased, the operating speed is fast and does not leak when switching.

  Further, the main body has a manual operation side rod fitting hole 70, the check valve 16 has a manual operation side rod 72 at the other end, and the manual operation side rod 72 has a manual operation side rod fitting hole 70. While sliding, it protrudes from the main body 12 to the outside.

  As a result, if the manual operation side rod 72 is provided on the opposite side of the solenoid 26, and the rod diameter is the same or substantially the same diameter as the automatic operation side rod 48, the hydraulic check valve 16 will be in a balanced state. The two elastic members 24 can be designed in an optimum state with respect to the solenoid 26. Even if the diameter of the check valve 16 is large, if the diameter of the manual operation side rod 72 is made equal to the diameter of the seal portion of the check valve 16 and the valve seat 46, the check valve 16 is hydraulically operated on the automatic operation side rod. Since the balance between the 48 side and the manual operation side rod 72 side is maintained, it is sufficient to balance the suction force of the solenoid 26 only with the force of the second elastic member 24. Thereby, the force (repulsive force) of the second elastic member 24 can be reduced.

  Furthermore, if the check valve 16 and the manual operation rod 72 are separate parts as shown in FIG. 3, the processing of the fitting hole on the main body 12 side is facilitated. In other words, a groove 74 having a width B and a height H is provided through the diameter φD of the check valve 16, and the manual operation side rod 72 is φD> φD ′, width B> with respect to each processing dimension on the check valve 16 side. B ′, height H> H ′ is provided, and the check valve 16 is provided with a slit 78 having a width d with respect to the diameter d ′ of the manually operated rod 72 so that d> d ′. The protrusion 74 is inserted into the groove 74 through the slit 78, and the check valve 16 and the manual operation rod 72 are assembled. If it is inserted into the check valve fitting hole 42 of the main body 12, the manual operation side rod 72 will not come off, and the check valve fitting hole 42 and the manual operation side rod fitting hole 70 are separated into fine cores by separate processing. There is no problem even if a deviation occurs.

  Furthermore, the diameter of the rod in the position having the two O-rings 66 and 68 of the automatic operation side rod 48 may be smaller than the diameter of the rod from the vicinity of the position to the valve seat 46 of the check valve 16.

  Thereby, since the check valve 16 system is adopted, the distance between the automatic operation side rod 48 and the check valve 16 and the valve seat 46 can be minimized, so that the diameter of the check valve 16 is changed to the diameter of the automatic operation side rod 48. It is possible to make the diameter smaller.

  Further, an oil groove 80 may be provided in a part of the check valve 16 along the sliding direction of the check valve 16.

  As a result, a stable diameter of the check valve 16 is made possible, so that a plurality of oil grooves 80 having sufficient flow paths can be provided around the periphery. Further, since the diameter can be increased, a plurality of oil grooves 80 serving as oil passages can be provided in the periphery, and the oil passage area can be sufficiently secured.

More specifically, FIG. 1 shows that the solenoid 26 is in a non-excited state, the hydraulic pressure in the hydraulic source side passage 28 and the cylinder side passage 32 are sealed by the seat of the spool 14, and FIG. In the state, the cylinder side passage 32 and the hydraulic pressure source are electrically connected, and the cylinder side passage 32 and the discharge (oil tank 32) are sealed by the seat of the spool 14.

A first cover 18 is attached to the upper side of the main body 12 and a second cover 20 is attached to the lower side with bolts or the like. A solenoid 26 is attached to the first cover 18. The main body 12 is provided with a first passage 30 for the hydraulic power source side passage 28, a second passage 34 for the cylinder side passage 32, and a third passage 38 for discharge. The first passage 30, the second passage 34, and the third passage 38 are provided. The passage 38 intersects with the spool fitting hole 40, and the first passage 30 also intersects with the check valve fitting hole 42. Further, depending on the arrangement of the pressure accumulator or the oil pump, connection ports may be provided at a plurality of positions of the main body as necessary for connection with these. The discharge third passage 38 does not intersect the check valve fitting hole 42 or the spring chamber 43 in which the second elastic member 24 is disposed, but intersects the third conduction port 44, and one of the third passages 38 is Sealed with a plug. The third conduction port 44 is opposed to the fourth conduction port 52 provided in the first cover 18.
A portion of the spool fitting hole 40 that intersects the first passage 30, the second passage 34, and the third passage 38 is provided with a flow passage in the entire circumference of the spool 14, and the first sheet 62 and the second sheet 64 (a). However, the first sheet 62 and the second sheet 64 (a) are tapered so that the first sheet 62 and the second sheet 64 (a) can slide smoothly. In addition, the spool 14 also has a portion that moves through each passage portion with a slightly smaller diameter to ensure a flow path area.

  In order to operate the spool 14 in the main body 12, the hydraulic pressure of the hydraulic source side passage 28 is supplied to the upper portion of the spool 14, and the supplied hydraulic pressure is returned to the discharge (oil tank) to return to the original state. The spool 14 is returned to the original position by the first elastic member 22.

  For this purpose, the check valve 16 has a valve seat 46 in the upper part, and the lower part is assembled in the check valve fitting hole 42 in a fitted state so that stable operation can be performed, and the check valve 16 is always attached to the first cover 18. A spring chamber 43 is provided on the valve seat 46 side of the check valve fitting hole 42 in order to attach the second elastic member 24 for pressing against the valve seat 46. An automatic operation side rod 48 provided between the valve seat 46 of the first cover 18 and the solenoid 26 is provided so as to be inserted into the automatic operation side rod fitting hole 50. The automatic operation side rod 48 has a push rod 82. There are two O-rings 66 and 68 on the side. The intervals between the O-rings 66 and 68 are located on the solenoid 26 side from the fifth conduction port 54 in the non-excited state in FIG. 1, and in the excited state, the two O-rings 66 and 68 are located in the excited state as shown in FIG. Are provided at intervals such that the fifth conduction ports 54 are positioned between them. The first conduction port 58 is provided closer to the mating surface with the main body than the fifth conduction port 54, and the interval between the fifth conduction port 54 and the first conduction port 58 is two O-rings 66, 68 when excited. The position of the first conduction port 58 is provided so that the O-ring 66 near the inner valve seat 46 is located between the fifth conduction port 54 and the first conduction port 58 as shown in FIG. A second guiding port 60 that leads from the first conduction port 58 to the hydraulic chamber 56 is provided. The automatic operation side rod 48 of the check valve 16 is slightly narrower than the diameter of the automatic operation side rod 48 from the valve seat 46 to the two O-rings 66 and 68 at the tip end side of the automatic operation side rod 48. A clearance is provided between the 48 fitting portion diameters so that the hydraulic pressure in the hydraulic source side passage 28 can easily flow into the hydraulic chamber 56 when the solenoid 26 is excited. An oil groove 80 is also provided in a part of the check valve 16 so that the hydraulic pressure can flow easily.

  In the non-excited state of FIG. 1, the check valve 16 is closed by the second elastic member 24 and the valve seat 46 is closed, and the discharge third passage 38 has the third conduction port 44, the fourth conduction port 52, and the automatic operation side. Since the rod fitting hole 50, the first conduction port 58, the second conduction port 60 and the hydraulic chamber 56 are all in communication with the discharge (oil tank side passage 36), the spool 14 is On the cover 18 side, the first passage 30 of the hydraulic pressure source side passage 28 of the spool 14 and the second passage 34 to the cylinder side passage 32 are blocked by the second seat 64 and discharged from the cylinder second passage 34 (oil (Tank) The third passage 38 is open because the first sheet 62 is open.

  2, when the solenoid 26 is energized, the push rod 82 is lowered (moved from the A position to the B position in FIG. 2), so that the automatic operation side rod 48 also compresses the second elastic member 24 and checks. In order to move the valve 16 to the right side in the figure, the valve seat 46 is opened, and the automatic operation side rod fitting hole 50 and the discharge (oil tank) are opened by two O-rings 66 and 68 provided on the tip side of the automatic operation side rod 48. Since the fifth conduction port 54 leading to the third passage 38 is blocked, the oil in the hydraulic source side passage 28 passes through the check valve 16 and passes through the automatic operation side rod fitting hole 50 to the first conduction port 58 and second The first elastic member 22 entering the hydraulic chamber 56 through the conduction port 60 and compressing the first elastic member 22 provided at the lower portion of the spool 14 is compressed to move the spool 14 to the right in FIG. Cylinder side passageway 34 32 for supplying to.

  Next, when the solenoid 26 returns to the non-excited state, the suction of the solenoid 26 is lost, so that the check valve 16 is closed by the spring force of the spring chamber 43, and the O-rings 66 and 68 at the tip of the automatic operation side rod 48 are 2 The two parts move from the fifth conduction port 54 to the left side in the figure, and the hydraulic chamber 56 has the second conduction port 60, the first conduction port 58, the automatic operation side rod fitting hole 50, the fifth conduction port 54, and the fourth conduction port. The port 52, the third conduction port 44, and the third passage 38 are conducted. As a result, the hydraulic pressure supplied to the upper portion of the spool fitting hole 40, which has moved the spool 14 to the right side in the figure, is discharged (oil tank), and the spool 14 moves to the left side in the figure by the spring force. Return to state.

  A pressure equalizing hole 83 is provided in the second cover 20 in the second cover 20 on the lower side of the spool 14 portion so that the spool 14 can smoothly move left and right in the drawing.

  Further, a manual operation side rod 72 is provided below the check valve 16 separately from the operation by the solenoid 26, and if the manual operation knob portion 84 is moved to the right side in the figure, the first passage 30 and the second passage 34 are manually operated. The third passage 38 can be switched. If the diameter of the manual operation side rod 72 is the same as the diameter of the automatic operation side rod 48, it moves smoothly (to the left in the figure) by the spring force of the spring chamber 43.

  Since the switching valve 10 of the present invention is a pilot type, the amount of oil required for the pilot is very small, and the first seat 62 and the second seat 64 are used for the first seat 62 and the second seat 64 even when the components and the diameter of the conduction port are narrow and the passage is switched. Since the second seat 64 is opened after the 62 is closed and vice versa, there is no loss in the amount of oil when switching. Further, since the first sheet 62 and the second sheet 64 of the spool 14 part can use soft sheets, there is no sheet leakage. Each part is sealed with an O-ring or the like.

  FIG. 4 shows an electro-hydraulic operating device 200 using this switching valve or an equivalent switching valve. In order to open and close the valve on both sides of the actuator 201, an opening cylinder 232 is shown on the right side in the figure, and a closing cylinder is shown on the left side in the figure. 232 'is provided, and the switching valve 10 is attached to each.

Although the above description has been made with respect to the embodiments, the present invention is not limited thereto, and is a technology of a switching valve that can be used for on / off of piping and line switching used in hydraulic equipment, equipment, and the like. It is clear that it can be generally used for hydraulic piping as well as a pneumatic switching valve of about 9.9 kg / cm ² or less. It will be apparent to those skilled in the art that various modifications and variations can be made within the spirit of the present invention and the scope of the appended claims.

DESCRIPTION OF SYMBOLS 10 Switching valve 12 Main body 14 Spool 16 Check valve 18 1st cover 20 2nd cover 22 1st elastic member 24 2nd elastic member 26 Solenoid 28 Hydraulic pressure source (accumulator or pump) side path 30 1st path 32 Cylinder side path 34 Second passage 36 Oil tank (discharge) side passage 38 Third passage 40 Spool fitting hole 42 Check valve fitting hole 43 Spring chamber 44 Third conduction port 46 Valve seat 48 Automatic operation side rod 50 Automatic operation side fitting hole 52 Fourth conduction port 54 Fifth conduction port 56 Hydraulic chamber 58 First conduction port 60 Second conduction port 62 First sheet 64 Second sheet 66 O-ring 68 O-ring 70 Manual operation side rod fitting hole 72 Manual operation side rod 74 Groove 76 Protrusion 78 Slit 80 Oil groove 82 Push rod 83 Pressure equalizing hole 84 Manual operation knob 100 Switching valve 114 Spool 124 Spring 126 Solenoid 128 Hydraulic source side passage 132 Cylinder side passage 136 Oil tank side passage 146 Valve seat 146 'Valve seat

  The present invention relates to a pilot-type switching valve using fluid pressure for supplying hydraulic pressure.

As shown in FIG. 5, a direct-acting switching valve is conventionally known. The switching valve 100 has the same mechanism as the switching valve of the present invention, but the type is a spool 114 (having valve seats 146, 146 'on both sides by the suction force of the solenoid 126 and the force of the spring 124 provided on the opposite side. The piston is actuated directly in the figure. That is, when the solenoid 126 is energized , the spool 114 moves to the left in the figure, the right valve seat 146 is opened, the left valve seat 146 'is closed, and the hydraulic pressure in the hydraulic source side passage 128 flows from the hydraulic source side passage 128 to the cylinder. Enter side passage 132. When de- energized , the spring 114 moves the spool 114 (piston) to the right, the right valve seat 146 is closed, the left valve seat 146 ′ is opened, and the cylinder side passage 132 is electrically connected to the oil tank side passage 136. This switching valve 100 is provided in each cylinder side passage 132, and oil in the hydraulic source side passage 128 enters the cylinder side passage 132 on the excited solenoid 126 side, so that the valves 146, 146 'are excited by the excitation of each solenoid 126. Opens and closes. The energized solenoid 126 is de- energized after confirmation by the limit switch after the cylinder side passage 132 is actuated. That is, excitation is performed only when the actuator is operated, and is not excited during standby.

However, when the switching valve 100 is energized and de- energized , the spool 114 (piston) is in an intermediate open state and is connected to the hydraulic source side passage 128 , the cylinder side passage 132, and the oil tank side passage 136, and the valve seats 146, 146 'are large. As a result, the hydraulic source side passage 128 is lost. In order to prevent this, if the force of the spring 124 is increased so as to operate quickly, the solenoid 126 must be increased in force, which makes it difficult to design the solenoid 126. Further, when employing the pilot spool to actuate the spool of the direct-acting, suction force of the solenoid which can be used is small, the diameter also small Kudekiru automatic operating side rods, the length of the pilot spool to actuate the spool The dimension in the direction needs to be the same length as the spool, and in order to switch to the first passage, the second passage, and the third passage, a thinner part and machining of the O-ring groove are necessary. It becomes. Moreover, it is difficult to produce a pilot spool without bending. If there is a bend, it will cause inoperability. Further, when switching is performed, there is a risk that fluid may leak from the switching valve. Further, when the left and right sealing sheets are opposite to each other as in the spool of the conventional example (see FIG. 5), the one-side sheet is always open, and both sheets are opened during operation, so that oil flows out to the tank. . To prevent this, it is necessary to increase the spring force and speed up the spool operation. However, if the spring force is increased, it becomes necessary to increase the suction force of the solenoid. Since this has a limit, the conventional switching valve cannot eliminate the leakage to the tank.

In order to solve the above-described problems, in the invention according to claim 1, a pilot-type switching valve using fluid pressure for supplying hydraulic pressure, comprising a main body, a spool, a check valve, and a first cover In the switching valve having the second cover, the first elastic member, the second elastic member, and the solenoid, the main body communicates with the first passage communicating with the hydraulic pressure source, the second passage communicating with the cylinder, and the oil tank. A third passage that crosses the first passage, the second passage, and the third passage, and a spool fitting hole that slides the spool, and a check that slides the check valve across the first passage. A valve fitting hole, a check valve fitting hole that intersects the first passage and the check valve slides, and a third conduction port that intersects the third passage, Automatic operation side at the valve seat and one end through the valve seat And the first cover communicates with one end of the check valve fitting hole, the automatic operation side rod fitting hole in which the automatic operation side rod of the check valve slides, and the third conduction A fourth conduction port communicating with the mouth, a fifth conduction port intersecting both the fourth conduction port and the automatic operation side rod fitting hole, a hydraulic chamber communicating with the spool fitting hole, and the automatic operation A first conduction port that intersects the side rod fitting hole, and a second conduction port that intersects the first conduction port and communicates with the hydraulic chamber, wherein the solenoid is the main body of the first cover. The spool is provided so as to slide on the automatic operation side rod, and the spool is formed by the first elastic member disposed between the main body and the second cover. The check valve is a second elastic member disposed on the main body. When the solenoid is de- energized by the first cover, the check valve fitting hole and the automatic operation side rod fitting hole are disconnected from each other by the check valve . The passage communicates with the third conduction port, the fourth conduction port, the fifth conduction port, the automatic rod fitting hole, the first conduction port, the second conduction port, and the hydraulic chamber, Oil from the source is not supplied to the cylinder, and when the solenoid is energized , the automatic operation side rod moves to the second cover side via the push rod, so that the check valve has the second elasticity. The member moves to the second cover side against the pressing force of the member, and disconnection of communication between the check valve fitting hole and the automatic operation side rod fitting hole by the check valve is released, 1 passage is fitted with the check valve A hole, the automatic rod fitting hole, the first conduction port, the second conduction port, the hydraulic chamber, and the spool against the pressing force of the first elastic member by oil from a hydraulic source. By moving to the second cover side, the first passage communicates with the second passage, and oil from a hydraulic pressure source is supplied to the cylinder.

Furthermore, in the invention according to claim 2, two O-rings are arranged on the automatic operation side rod, and when the solenoid is de - energized , the two O-rings are closer to the solenoid side than the fifth conduction port. When the solenoid is energized , the two O-rings are arranged so as to sandwich the fifth conduction port so that the fifth conduction port and the automatic operation side rod fitting hole do not communicate with each other. It is characterized by being.

In the invention according to claim 3, the spool has a first sheet and a second sheet, and when the solenoid is de - energized , the first sheet has the third passage and the second passage. However, when the solenoid is energized , the first seat moves between the third passage and the second passage , but the second seat blocks communication between the first passage and the second passage . to block the communication path, but the second sheet, characterized in that the communication of the second passage and the first passage is configured so as not to cut off.

  Furthermore, in the invention which concerns on Claim 4, the said main body has a manual operation side rod fitting hole, The said check valve has a manual operation side rod in the other end part, The said manual operation side rod is the said manual operation side. The operation side rod fitting hole slides and protrudes from the main body to the outside.

In the invention according to claim 5, the diameter of the rod from the vicinity of the position to the valve seat of the check valve is smaller than the diameter of the rod at the position having the two O-rings of the automatic operation side rod. It is characterized by.

  Further, the invention according to claim 6 is characterized in that an oil groove is provided in a part of the check valve along a sliding direction of the check valve.

According to the first aspect of the present invention, if the automatic operation side rod and the valve seat seal portion of the check valve have substantially the same diameter, the length is short even if a portion thinner than the diameter of the automatic operation side rod fitting hole is provided. Since there are no parts, processing is easy. Even if the diameter of the check valve is large, if the diameter of the rod on the manual operation side is the same as the diameter of the check valve and valve seat seal, the check valve maintains the balance between the automatic side and the manual side with hydraulic pressure. Therefore, it is sufficient to balance the attraction force of the solenoid only with the force of the second elastic member. Thereby, the force (repulsive force) of the second elastic member can be reduced. Therefore, since the check valve can take a long fitting part with the main body, sufficient safety can be obtained in operation. Further, since the diameter can be increased, a plurality of oil grooves serving as oil passages can be provided in the periphery, and the oil passage area can be sufficiently secured. Further, since the spool is not operated by the suction force of the solenoid but is operated by the hydraulic pressure entering the hydraulic chamber, the diameter and the stroke can be freely set, and the flow paths to the first passage, the second passage, and the third passage. Since the spool has a large diameter, there is no problem in processing even if it is thin.

According to the invention of claim 2, two O-ring land, O-ring of the valve seat side, to the hydraulic chamber hydraulic from hydraulic pressure source to the excitation, the oil tank return and the flow path from the hydraulic chamber to a non-energized It becomes a seal that changes. The O-ring on the side away from the valve seat is not necessary for the type that requires oil in the solenoid, and is required for the type that does not require oil, and can be applied to any type of solenoid.

According to the invention of claim 3, the spool uses a high-pressure hydraulic source hydraulic pressure for its operation, and the pressure receiving diameter can be increased, and the seal is performed at the fitting portion, and the diameter of the spool when the flow path is opened. Can be thinned to have a sufficient diameter of the flow path. Further, the first elastic member does not need to be adjusted to the load entering the hydraulic chamber, and it is sufficient if there is a force for operating the spool. Furthermore, oil can be prevented from flowing into the tank. Further, the first sheet and the second sheet are not opened at the same time, and the necessary side is opened after both sheets are sealed. And since the spool diameter can be increased, the operating speed is fast and does not leak when switching. Further, the first and second sheets of the spool can seal the hydraulic pressure of the fitting portion only when the spool fitting hole and the spool are in the fitting portion where the spool can be sealed.

According to the invention of claim 4, if the manual operation side rod is provided on the opposite side of the solenoid, and the rod diameter is the same or substantially the same diameter as the automatic operation side rod, the hydraulic check valve is in a balanced state. Thus, the second elastic member can be designed in an optimum state with respect to the solenoid. Even if the diameter of the check valve is large, if the diameter of the manually operated rod is the same as the diameter of the check valve and valve seat seal, the hydraulic pressure between the automatic operation side rod side and the manual operation side rod side of the check valve Therefore, it is sufficient to balance the attraction force of the solenoid only with the force of the second elastic member. Thereby, the force (repulsive force) of the second elastic member can be reduced.

  According to the invention which concerns on Claim 5, since it is possible to make the space between an automatic operation side rod, a check valve, and a valve seat into the minimum dimension by adoption of a check valve system, the diameter of a check valve is made into the automatic operation side rod. It is possible to make the diameter thinner than the diameter.

  According to the invention which concerns on Claim 6, it becomes possible to provide the oil groove which has multiple and sufficient flow paths in the circumference | surroundings by enabling the diameter of the stable check valve. Further, since the diameter can be increased, a plurality of oil grooves serving as oil passages can be provided in the periphery, and the oil passage area can be sufficiently secured.

It is a figure which shows sectional drawing of the switching valve with which the solenoid of one Example of this invention is a non- excitation . It is a figure which shows sectional drawing of the switching valve with which the solenoid of one Example of this invention is an excitation . It is a figure which shows the check valve and manual operation side rod of one Example of this invention. It is a system diagram when the switching valve of the present invention is mounted on an electrohydraulic operating device. It is a figure which shows the partial cross section figure of the direct-acting switching valve of a prior art.

  Other objects, features and advantages of the present invention will become apparent from the following description of embodiments of the present invention with reference to the accompanying drawings.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Corresponding components are denoted by common reference symbols throughout the drawings.

  Referring to FIGS. 1 and 2, a pilot-type switching valve 10 using fluid pressure for supplying hydraulic pressure includes a main body 12, a spool 14, a check valve 16, a first cover 18, and a second cover. 20, a first elastic member 22, a second elastic member 24, and a solenoid 26. First, the main body 12 includes a first passage 30 communicating with the hydraulic source side passage 28, a second passage 34 communicating with the cylinder side passage 32, a third passage 38 communicating with the oil tank side passage 36, and a first passage. 30, a spool fitting hole 40 that intersects the second passage 34 and the third passage 38, and the spool 14 slides, and a check valve fitting hole 42 that intersects the first passage 30 and the check valve 16 slides. The check valve fitting hole 42 intersects with the first passage 30 and the check valve 16 slides, and the third conduction port 44 intersects with the third passage 38. Next, the check valve 16 has a valve seat 46 and an automatic operation side rod 48 at one end portion through the valve seat 46. Further, the first cover 18 communicates with one end of the check valve fitting hole 42, the automatic operation side rod fitting hole 50 in which the automatic operation side rod 48 of the check valve 16 slides, and the third conduction port 44. A fourth conduction port 52 that communicates, a fifth conduction port 54 that intersects both the fourth conduction port 52 and the automatic operation side rod fitting hole 50, a hydraulic chamber 56 that communicates with the spool fitting hole 40, and automatic operation It has a first conduction port 58 that intersects the side rod fitting hole 50 and a second conduction port 60 that intersects the first conduction port 58 and communicates with the hydraulic chamber 56. The hydraulic chamber 56 does not have to be a concave chamber as shown in FIG. 1, and only the O-ring may be provided. The solenoid 26 is provided on the side opposite to the main body 12 of the first cover 18 so as to slide the automatic operation side rod 48, and the spool 14 is interposed between the main body 12 and the second cover 20. The first elastic member 22 arranged is pressed against the first cover 18, and the check valve 16 is pushed against the first cover 18 by the second elastic member 24 arranged on the main body 12.

When the solenoid 26 is de- energized , the check valve fitting hole 42 and the automatic operation side rod fitting hole 50 are disconnected from each other by the valve seat 46 of the check valve 16 , and the third passage 38 is connected to the third passage 38. The conduction port 44, the fourth conduction port 52, the fifth conduction port 54, the automatic operation side rod fitting hole 50, the first conduction port 58, the second conduction port 60, and the hydraulic chamber 56 communicate with each other. Is not supplied to the cylinder side passage 32.

When the solenoid 26 is energized , the automatic operation side rod 48 moves to the second cover 20 side, whereby the check valve 16 moves to the second cover 20 side against the pressing force of the second elastic member 24, The disconnection of the communication between the check valve fitting hole 42 by the valve seat 46 of the check valve 16 and the automatic operation side rod fitting hole 50 is released, and the first passage 30 has the check valve fitting hole 42, automatic operation The side rod fitting hole 48, the first conduction port 58, the second conduction port 60, and the hydraulic chamber 56 communicate with each other, and the spool 14 opposes the pressing force of the first elastic member 22 by the oil from the hydraulic source side passage 28. By moving to the second cover 20 side, the first passage 30 communicates with the second passage 34 and is configured to supply oil from the hydraulic source side passage 28 to the cylinder side passage 32 .

In order to improve the sealing performance, the fitting portion between the main body 12 and the spool 14 may be sealed using an O-ring or the like.

  As a result, if the automatic operation side rod 48 and the valve seat 46 seal portion have substantially the same diameter, even if a portion thinner than the diameter of the automatic operation side rod fitting hole 50 is provided, the length is short and there is no seal portion. Is easy. Accordingly, since the check valve 16 can be fitted with the main body 12 for a long time, the operation can be sufficiently safe. Further, since the spool 14 is not operated by the suction force of the solenoid 26 but is operated by the hydraulic pressure entered in the hydraulic chamber 56, the diameter and the stroke can be freely set, and the first passage 30, the second passage 34, and the third passage. Since the diameter of the spool 14 is large in the flow path to the passage 38, there is no problem in processing even if it is thin.

Further, two O-rings 66 and 68 are disposed on the automatic operation side rod 48. When the solenoid 26 is not excited , the two O-rings 66 and 68 are disposed closer to the solenoid 26 than the fifth conduction port 54. When the solenoid 26 is excited , the two O-rings 66 and 68 are arranged so as to sandwich the fifth conduction port 54 so that the fifth conduction port 54 and the automatic operation side rod fitting hole 50 do not communicate with each other. ing.

As a result, of the two O-rings 66 and 68, the O-ring 66 on the valve seat 46 side excites the hydraulic pressure from the hydraulic source side passage 28 to the hydraulic chamber 56, and the non- excitation from the hydraulic chamber 56 to the oil tank side passage. 36 It becomes a seal that changes the return and flow path. The O-ring 68 on the side away from the valve seat 46 is not required in the case where the solenoid 26 requires oil, and is required in the case where the oil does not need oil. The O-ring 68 can be applied to any type of solenoid 26. is there.

Further, the spool 14 includes a first sheet 62 and a second sheet 64. When the solenoid 26 is not excited , the first sheet 62 does not block communication between the third passage 38 and the second passage 34 . The second sheet 64 blocks communication between the first passage 30 and the second passage 34 , and when the solenoid 26 is excited , the first sheet 62 blocks communication between the third passage 38 and the second passage 34. The second sheet 64 is configured not to block communication between the first passage 30 and the second passage 34 .

As a result, the spool 14 uses the hydraulic pressure of the hydraulic pressure source for its operation, and the pressure receiving diameter can be increased, and the seal is performed by the first sheet and the second sheet provided in the fitting portion, and the flow path is opened. Sometimes the diameter can be reduced to a sufficient diameter for the channel. Further, the first elastic member 22 does not need to be adjusted to the load that has entered the hydraulic chamber 56, and it is sufficient if there is a force for operating the spool 14. Furthermore, oil can be prevented from flowing out to the oil tank side passage 36. In addition, the first sheet 62 and the second sheet 64 are not opened at the same time , and the necessary sheet side is opened after sealing with both sheets 62 and 64 without fail. Since the diameter of the spool 14 can be increased, the operating speed is fast and no leakage occurs during switching.

  Further, the main body has a manual operation side rod fitting hole 70, the check valve 16 has a manual operation side rod 72 at the other end, and the manual operation side rod 72 has a manual operation side rod fitting hole 70. While sliding, it protrudes from the main body 12 to the outside.

As a result, if the manual operation side rod 72 is provided on the opposite side of the solenoid 26, and the rod diameter is the same or substantially the same diameter as the automatic operation side rod 48, the hydraulic check valve 16 will be in a balanced state. The two elastic members 24 can be designed in an optimum state with respect to the solenoid 26. Even if the check valve 16 has a large diameter, if the diameter of the manually operated rod 72 is made equal to the diameter of the seal portion of the valve seat 46 of the check valve 16, the check valve 16 is hydraulically operated on the automatic operation side rod. Since the balance between the 48 side and the manual operation side rod 72 side is maintained, it is sufficient to balance the suction force of the solenoid 26 only with the force of the second elastic member 24. Thereby, the force (repulsive force) of the second elastic member 24 can be reduced.

Furthermore, if the check valve 16 and the manual operation rod 72 are separate parts as shown in FIG. 3, the processing of the fitting hole on the main body 12 side is facilitated. In other words, a groove 74 having a width B and a height H is provided through the diameter φD of the check valve 16, and the manual operation side rod 72 is φD> φD ₁ , width B> with respect to each processing dimension on the check valve 16 side. A protrusion 76 having a height B ^> and a height H> H ^| is provided, and a slit 78 having a width d is provided in the check valve 16 with respect to the diameter d ^| of the manual operation side rod 72 so that d> d ^| The protrusion 76 is inserted into the groove 74 through the slit 78, and the check valve 16 and the manual operation rod 72 are assembled. If it is inserted into the check valve fitting hole 42 of the main body 12, the manual operation side rod 72 will not come off, and the check valve fitting hole 42 and the manual operation side rod fitting hole 70 are separated into fine cores by separate processing. There is no problem even if a deviation occurs.

Furthermore, from the diameter of the position of the rod with two of the O-ring 66 and 68 of the automatic operation side rod 48, the diameter of the rod from the vicinity of the position to the valve seat 46 of the check valve 16 may be small.

  Thereby, since the check valve 16 system is adopted, the distance between the automatic operation side rod 48 and the check valve 16 and the valve seat 46 can be minimized, so that the diameter of the check valve 16 is changed to the diameter of the automatic operation side rod 48. It is possible to make the diameter smaller.

  Further, an oil groove 80 may be provided in a part of the check valve 16 along the sliding direction of the check valve 16.

  As a result, a stable diameter of the check valve 16 is made possible, so that a plurality of oil grooves 80 having sufficient flow paths can be provided around the periphery. Further, since the diameter can be increased, a plurality of oil grooves 80 serving as oil passages can be provided in the periphery, and the oil passage area can be sufficiently secured.

More specifically, in FIG. 1, the solenoid 26 is in a non- excited state, the hydraulic pressure in the hydraulic source side passage 28 and the cylinder side passage 32 are sealed by the second seat 64 of the spool 14, and FIG. In the excited state, the cylinder side passage 32 and the hydraulic source side passage 28 are electrically connected, and the cylinder side passage 32 and the oil tank (discharge) side passage 36 are sealed by the first seat 62 of the spool 14.

A first cover 18 is attached to the upper side of the main body 12 and a second cover 20 is attached to the lower side with bolts or the like. A solenoid 26 is attached to the first cover 18. The main body 12 is provided with a first passage 30 for the hydraulic pressure source side passage 28, a second passage 34 for the cylinder side passage 32, and a third passage 38 for the oil tank (discharge) side passage 36 . The second passage 34 and the third passage 38 intersect with the spool fitting hole 40, and the first passage 30 also intersects with the check valve fitting hole 42. Further, depending on the arrangement of the pressure accumulator or the oil pump, connection ports may be provided at a plurality of positions of the main body as necessary for connection with these. The third passage 38 for the oil tank (discharge) side passage 36 does not intersect the check valve fitting hole 42 or the spring chamber 43 in which the second elastic member 24 is disposed, but intersects the third conduction port 44. One of the third passages 38 is sealed with a plug. The third conduction port 44 is opposed to the fourth conduction port 52 provided in the first cover 18. The spool fitting hole 40 is provided with a flow passage in the entire circumference of the spool 14 at a portion intersecting the first passage 30, the second passage 34, and the third passage 38, and the first sheet 62 and the second sheet 64 are provided in the passage portion. In order to prevent damage, the first sheet 62 and the second sheet 64 are tapered so that the first sheet 62 and the second sheet 64 can slide smoothly. In addition, the spool 14 also has a portion that moves through each passage portion with a slightly smaller diameter to ensure a flow path area.

In order to operate the spool 14 in the main body 12, the hydraulic pressure of the hydraulic source side passage 28 is supplied to the upper portion of the spool 14, and the supplied hydraulic pressure is returned to the oil tank (discharge) side passage 36. The spool 14 is returned to the original position by the first elastic member 22 at the lower part of the front side.

For this purpose, the check valve 16 has a valve seat 46 in the upper part, and the lower part is assembled in the check valve fitting hole 42 in a fitted state so that stable operation can be performed, and the check valve 16 is always attached to the first cover 18. A spring chamber 43 is provided on the valve seat 46 side of the check valve fitting hole 42 in order to attach the second elastic member 24 for pressing against the valve seat 46. An automatic operation side rod 48 provided between the valve seat 46 of the first cover 18 and the solenoid 26 is provided so as to be inserted into the automatic operation side rod fitting hole 50. The automatic operation side rod 48 has a push rod 82. There are two O-rings 66 and 68 on the side. The distance between the O-ring 66, 68 deenergized in two places both in FIG. 1, located on the solenoid 26 side than the fifth conduction port 54, between the two locations of the O-ring 66 and 68 as shown in FIG. 2 in an energized state Are provided at intervals such that the fifth conduction ports 54 are positioned. The first conduction port 58 is provided closer to the mating surface with the main body with respect to the fifth conduction port 54, and the interval between the fifth conduction port 54 and the first conduction port 58 is such that the two O-rings 66 and 68 are at the time of excitation . The position of the first conduction port 58 is provided so that the O-ring 66 near the inner valve seat 46 is located between the fifth conduction port 54 and the first conduction port 58 as shown in FIG. A second conduction port 60 that leads from the first conduction port 58 to the hydraulic chamber 56 is provided. The automatic operation side rod 48 of the check valve 16 is slightly narrower than the diameter of the automatic operation side rod 48 from the valve seat 46 to the two O-rings 66 and 68 at the tip end side of the automatic operation side rod 48. A clearance is provided between the 48 fitting portion diameters so that the hydraulic pressure in the hydraulic source side passage 28 can easily flow into the hydraulic chamber 56 when the solenoid 26 is excited . An oil groove 80 is also provided in a part of the check valve 16 so that the hydraulic pressure can flow easily.

In the non- excited state of FIG. 1, the check valve 16 is closed by the second elastic member 24 and the valve seat 46 is closed, and the third passage 38 for the oil tank (discharge) side passage 36 has the third conduction port 44 and the fourth passage. Since the conduction port 52, the automatic operation side rod fitting hole 50, the first conduction port 58, the second conduction port 60, and the hydraulic chamber 56 are all in communication with the oil tank (discharge) side passage 36 , the spool 14 The elastic member 22 is on the first cover 18 side, whereby the first passage 30 of the hydraulic pressure source side passage 28 of the spool 14 and the second passage 34 to the cylinder side passage 32 are blocked by the second seat 64, and the cylinder second The passage 34 and the third passage 38 for the oil tank (discharge) side passage 36 communicate with each other because the first seat 62 is in an open state.

In the solenoid 26 excitation state of FIG. 2, the solenoid 26 is excited and the push rod 82 descends (moves from the A position to the B position in FIG. 2), whereby the automatic operation side rod 48 also compresses the second elastic member 24 and the check valve 16 Is moved to the right side in the figure, and the valve seat 46 is opened, and the automatic operation side rod fitting hole 50 and the oil tank (discharge) side passage are formed by two O-rings 66 and 68 provided on the distal end side of the automatic operation side rod 48. Since the fifth conduction port 54 leading to the third passage 38 to 36 is blocked, the oil in the hydraulic pressure source side passage 28 passes through the check valve 16 and the automatic operation side rod fitting hole 50, and passes through the first conduction port 58 and the first conduction port 58. The first elastic member 22 that enters the hydraulic chamber 56 through the second conduction port 60 and compresses the spool 14 at the lower portion is compressed to move the spool 14 to the right in the drawing, so that the oil in the hydraulic source side passage 28 flows from the first passage 30 to the first passage 30. 2 passage 34 Supplied to the Sunda side passage 32.

Next, when the solenoid 26 returns to the non- excited state, the suction of the solenoid 26 is lost, so that the check valve 16 is closed by the spring force of the spring chamber 43, and there are two O-rings 66, 68 at the tip of the automatic operation side rod 48. The hydraulic chamber 56 moves from the fifth conduction port 54 to the left side in the figure, and the hydraulic chamber 56 has a second conduction port 60, a first conduction port 58, an automatic operation side rod fitting hole 50, a fifth conduction port 54, and a fourth conduction port. 52, the third conduction port 44 and the third passage 38 are conducted. As a result, the hydraulic pressure supplied to the upper portion of the spool fitting hole 40, which has moved the spool 14 to the right in the figure, is discharged to the oil tank (discharge) side passage 36, and the spool 14 moves to the left in the figure by the spring force. 1 Return to the non- excited state.

To switch to a spool 14 parts second cover 20 of the lower to the spool 14 is moved smoothly right and left in the figure, equalizing pressure hole 83 is provided.

  Further, a manual operation side rod 72 is provided below the check valve 16 separately from the operation by the solenoid 26, and if the manual operation knob portion 84 is moved to the right side in the figure, the first passage 30 and the second passage 34 are manually operated. The third passage 38 can be switched. If the diameter of the manual operation side rod 72 is the same as the diameter of the automatic operation side rod 48, it moves smoothly (to the left in the figure) by the spring force of the spring chamber 43.

  Since the switching valve 10 of the present invention is a pilot type, the amount of oil required for the pilot is very small, and the first seat 62 and the second seat 64 are used for the first seat 62 and the second seat 64 even when the components and the diameter of the conduction port are narrow and the passage is switched. Since the second seat 64 is opened after the 62 is closed and vice versa, there is no loss in the amount of oil when switching. Further, since the first sheet 62 and the second sheet 64 of the spool 14 part can use soft sheets, there is no sheet leakage. Each part is sealed with an O-ring or the like.

  FIG. 4 shows an electro-hydraulic operating device 200 using this switching valve or an equivalent switching valve. In order to open and close the valve on both sides of the actuator 201, an opening cylinder 232 is shown on the right side in the figure, and a closing cylinder is shown on the left side in the figure. 232 'is provided, and the switching valve 10 is attached to each.

Although the above description has been made with respect to the embodiments, the present invention is not limited thereto, and is a technology of a switching valve that can be used for on / off of piping and line switching used in hydraulic equipment, equipment, and the like. It is clear that it can be generally used for hydraulic piping as well as a pneumatic switching valve of about 9.9 kg / cm ² or less. It will be apparent to those skilled in the art that various modifications and variations can be made within the spirit of the present invention and the scope of the appended claims.

DESCRIPTION OF SYMBOLS 10 Switching valve 12 Main body 14 Spool 16 Check valve 18 1st cover 20 2nd cover 22 1st elastic member 24 2nd elastic member 26 Solenoid 28 Hydraulic pressure source (accumulator or pump) side path 30 1st path 32 Cylinder side path 34 Second passage 36 Oil tank (discharge) side passage 38 Third passage 40 Spool fitting hole 42 Check valve fitting hole 43 Spring chamber 44 Third conduction port 46 Valve seat 48 Automatic operation side rod 50 Automatic operation side fitting hole 52 Fourth conduction port 54 Fifth conduction port 56 Hydraulic chamber 58 First conduction port 60 Second conduction port 62 First sheet 64 Second sheet 66 O-ring 68 O-ring 70 Manual operation side rod fitting hole 72 Manual operation side rod 74 Groove 76 Protrusion 78 Slit 80 Oil groove 82 Push rod 83 Pressure equalizing hole 84 Manual operation knob 100 Switching valve 114 Spool 124 Spring 126 Solenoid 128 Hydraulic source side passage 132 Cylinder side passage 136 Oil tank side passage 146 Valve seat 146 'Valve seat

Claims (6)

A pilot-type switching valve using fluid pressure to supply hydraulic pressure,
In a switching valve having a main body, a spool, a check valve, a first cover, a second cover, a first elastic member, a second elastic member, and a solenoid,
The main body intersects a first passage communicating with a hydraulic pressure source, a second passage communicating with a cylinder, a third passage communicating with an oil tank, the first passage, the second passage, and the third passage, A spool fitting hole through which the spool slides, a check valve fitting hole through which the check valve slides, a check valve through which the check valve slides, and a check valve through which the check valve slides A fitting hole and a third conduction port intersecting the third passage,
The check valve has a valve seat and an automatic operation side rod at one end portion through the valve seat,
The first cover communicates with one end portion of the check valve fitting hole, and communicates with the automatic operation side rod fitting hole through which the automatic operation side rod of the check valve slides and the third conduction port. A fourth conduction port, a fifth conduction port intersecting with both the fourth conduction port and the automatic operation side rod fitting hole, a hydraulic chamber communicating with the spool fitting hole, and the automatic operation side rod fitting hole A first conduction port that intersects with the first conduction port and a second conduction port that communicates with the hydraulic chamber,
The solenoid is provided on the opposite side of the first cover from the main body so as to slide the automatic operation side rod,
The spool is pressed against the first cover by the first elastic member disposed between the main body and the second cover, and the check valve is pressed by the second elastic member disposed on the main body. Pressed by the first cover,
The spool has a first sheet and a second sheet, and when the solenoid is not excited,
The first sheet does not block communication between the third passage and the spool fitting hole, but the second sheet blocks communication between the first passage and the spool fitting hole, and the solenoid is energized. In this case, the first sheet blocks communication between the third passage and the spool fitting hole, but the second sheet does not block communication between the first passage and the spool fitting hole. And
When the solenoid is in a non-excited state, the check valve fitting hole and the automatic operation side rod fitting hole are disconnected from each other by the valve seat, and the third passage includes the third conduction port, The fourth conduction port, the fifth conduction port, the automatic operation side rod fitting hole, the first conduction port, the second conduction port, and the hydraulic chamber communicate with each other, and oil from the hydraulic source is supplied to the cylinder. Without
When the solenoid is energized, the automatic operation side rod moves to the second cover side, so that the check valve moves to the second cover side against the pressing force of the second elastic member. The blocking of the communication between the check valve fitting hole by the valve seat and the automatic operation side rod fitting hole is released, and the first passage includes the check valve fitting hole and the automatic operation side rod. The spool communicates with the fitting hole, the first conduction port, the second conduction port, and the hydraulic chamber, and the spool is opposed to the pressing force of the first elastic member by the oil from the hydraulic source, and the second cover side The switching valve is configured such that the first passage communicates with the second passage and supplies oil from a hydraulic pressure source to the cylinder by moving to the cylinder.   Two O-rings are disposed on the automatic operation side rod, and when the solenoid is not energized, the two O-rings are disposed on the solenoid side with respect to the fifth conduction port, and the solenoid is energized. 2. The switching valve according to claim 1, wherein the two O-rings are respectively disposed so as to sandwich the fifth conduction port so as not to communicate the fifth conduction port and the automatic operation side rod fitting hole. . The spool has a first sheet and a second sheet, and when the solenoid is not excited,
The first sheet does not block communication between the third passage and the spool fitting hole, but the second sheet blocks communication between the first passage and the spool fitting hole, and the solenoid is energized. In this case, the first sheet blocks communication between the third passage and the spool fitting hole, but the second sheet does not block communication between the first passage and the spool fitting hole. The change-over valve according to claim 1 or 2 constituted.   The main body has a manual operation side rod fitting hole, the check valve has a manual operation side rod at the other end, and the manual operation side rod slides in the manual operation side rod fitting hole. The switching valve according to any one of claims 1 to 3, which protrudes outward from the main body.   The diameter of the rod at the position having the two O-rings of the automatic operation side rod is smaller than the diameter of the rod from the vicinity of the position to the valve seat of the check valve. The switching valve described in 1.   The switching valve according to claim 1, wherein an oil groove is provided in a part of the check valve along a sliding direction of the check valve.