JP6227520B2 - Internal pilot type 3 port selector valve - Google Patents

Description

  The present invention relates to an internal pilot type 3-port switching valve.

  The three-port switching valve has a smaller number of ports than the five-port switching valve, and is a preferable switching valve for downsizing the switching valve itself. As such a three-port switching valve, for example, a balanced poppet solenoid valve disclosed in Patent Document 1 is known. The balance poppet type solenoid valve has a body in which a valve hole for accommodating the poppet valve is formed. The body has a supply port, an output port, and a discharge port from one end side to the other end side in the axial direction of the poppet valve. Are arranged in this order so as to communicate with the valve holes, respectively.

  The balance poppet type solenoid valve includes a solenoid unit integrated with the body. The solenoid unit includes a fixed iron core, a movable iron core disposed opposite to the fixed iron core, and an iron core spring that urges the movable iron core in a direction away from the fixed iron core. A poppet valve is in contact with an end surface of the movable iron core opposite to the fixed iron core. A valve spring that biases the poppet valve toward the solenoid portion is disposed on the opposite side of the body from the solenoid portion. The biasing force of the valve spring is smaller than the biasing force of the iron core spring.

  When the power supply to the solenoid coil is stopped, the movable iron core is moved away from the fixed iron core due to the difference in biasing force between the iron core spring and the valve spring, and the poppet valve moves toward the valve spring. To do. As a result, the gap between the supply port and the output port is sealed, and the compressed fluid is not supplied from the supply port to the fluid pressure device via the output port. On the other hand, when power is supplied to the coil of the solenoid part, the movable iron core is attracted toward the fixed iron core against the urging force of the iron core spring, and the poppet valve is urged by the valve spring. Moves toward the solenoid. As a result, the supply port and the output port communicate with each other, and the compressed fluid is supplied from the supply port to the fluid pressure device via the output port.

  In the balance poppet solenoid valve having the above configuration, when the supply of power to the coil of the solenoid unit is stopped, the supply of compressed fluid from the supply port to the fluid pressure device via the output port is not performed. And when electric power is supplied to the coil of the solenoid part, it is used as a normally closed type in which compressed fluid is supplied from the supply port to the fluid pressure device via the output port.

  By the way, in a balanced poppet solenoid valve, a port used as a supply port may be used as a discharge port, and a port used as a discharge port may be used as a supply port. In this case, when the power supply to the coil of the solenoid unit is stopped, the compressed fluid is supplied from the supply port to the fluid pressure device through the output port, and the power supply to the coil of the solenoid unit is also performed. Is performed, it is used as a normally open type in which compressed fluid is not supplied from the supply port to the fluid pressure device via the output port.

  Further, in the balanced poppet solenoid valve, the port used as the output port is used as the supply port, the port used as the supply port is used as the first output port, and the port used as the discharge port is used as the second output port. Sometimes used as an output port. In this case, when the power supply to the coil of the solenoid unit is stopped, the compressed fluid is supplied from the supply port to the fluid pressure device via the first output port, and the power to the coil of the solenoid unit is also supplied. Is supplied, the compressed fluid is supplied from the supply port to the fluid pressure device via the second output port, so-called A / B output type.

  Thus, the balance poppet type solenoid valve is one type of balance poppet type solenoid valve, and can correspond to a normally closed type, a normally open type, and an A / B output type.

  However, in the balance poppet type solenoid valve of Patent Document 1, in order to increase the flow rate of the compressed fluid supplied to the fluid pressure device, it is necessary to increase the stroke of the poppet valve. It is necessary to increase the suction force, which increases power consumption.

  Therefore, in order to increase the flow rate of the compressed fluid supplied to the fluid pressure device while suppressing power consumption, a pilot type three-port switching valve that reciprocates the spool valve body using the pilot pressure of the pilot fluid is conceivable.

  A first piston and a second piston are mounted on both ends of the spool valve body. The first piston is reciprocally accommodated in a first piston chamber formed at one end of the spool valve body in the body, and the second piston is a second piston formed at the other end of the spool valve body in the body. It is accommodated in the two-piston chamber so that it can reciprocate. The first piston has a larger diameter than the second piston. A first pilot pressure chamber is defined in the first piston chamber by the first piston, and a second pilot pressure chamber is defined in the second piston chamber by the second piston.

  The pilot-type three-port switching valve includes a first pilot flow path communicating with the first pilot pressure working chamber and a second pilot flow path communicating with the second pilot pressure working chamber. Further, the pilot type 3-port switching valve includes a pilot valve portion that opens and closes the first pilot flow path. The pilot valve portion is a known electromagnetic valve that opens when power is supplied to the solenoid portion and closes when power supply to the solenoid portion is stopped. The pilot fluid is always supplied from the second pilot flow path to the second pilot pressure working chamber.

  Then, by supplying electric power to the solenoid part, the pilot valve part is opened, and the pilot fluid is supplied from the first pilot flow path to the first pilot pressure working chamber. As a result, the spool valve body moves toward the second piston chamber due to the difference in pressure receiving area between the first piston and the second piston. When the supply of electric power to the solenoid unit is stopped, the pilot valve unit is closed, and the pilot fluid is not supplied from the first pilot flow path to the first pilot pressure working chamber. As a result, the spool valve body moves toward the first piston chamber by the pressure in the second pilot pressure working chamber. By the movement of the spool valve body, the communication states of the supply port, the output port, and the discharge port are switched.

  By the way, an internal pilot type 3 port switching valve for supplying the compressed fluid supplied to the supply port to the first pilot pressure working chamber and the second pilot pressure working chamber is different from the supply port. There is an external pilot type three-port switching valve that supplies compressed fluid supplied from the outside to the first pilot pressure working chamber and the second pilot pressure working chamber. Since the external pilot type 3 port switching valve needs to be separately provided with an external pipe for supplying pilot fluid, an internal pilot type 3 port switching valve that does not require a separate external pipe for supplying pilot fluid may be used.

Japanese Patent No. 5486987

  By the way, in the internal pilot type 3-port switching valve, the supply port and the first pilot flow path and the second pilot flow path communicate with each other. That is, since the relative position between the supply port and the first pilot flow path and the second pilot flow path is uniquely determined, the port used as the supply port is used as the discharge port, such as a balanced poppet solenoid valve. At the same time, the port used as the discharge port cannot be used as the supply port.

  For the internal pilot type 3 port switching valve, prepare two types of spool valve body corresponding to normal close type and spool valve body corresponding to normal open type when trying to correspond to normal close type and normal open type. Therefore, problems such as an increase in the number of parts and a troublesome part inventory management occur.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an internal pilot that can correspond to a normally closed type, a normally open type, and an A / B output type with a single type of switching valve. An object is to provide a three-port switching valve.

An internal pilot type three-port switching valve that solves the above problems has a body in which a valve hole that accommodates a spool valve body so as to be capable of reciprocating movement is formed, and the body communicates with the valve hole, and the spool In the axial direction of the valve body, it has a first port, a second port, and a third port arranged in order from one end side to the other end side, and a pilot pressure working chamber is provided on the end side of the spool valve body in the body. A first valve seat on which the first valve portion of the spool valve body is seated is provided between the first port and the second port on the inner peripheral surface of the valve hole, and the second port; A second valve seat on which the second valve portion of the spool valve body is seated is provided between the pilot port and the third port, and the pilot fluid is supplied to the pilot pressure working chamber by supplying electric power to the solenoid portion of the pilot valve portion. Is The internal pilot type three-port switching valve in which the spool valve body moves to one end side, wherein the first valve portion is one end in the axial direction of the spool valve body rather than the first valve seat in the valve hole. The second valve chamber is housed in a first valve chamber provided nearer and the second valve portion is provided closer to the other axial end of the spool valve body than the second valve seat in the valve hole. And the body includes a first pilot channel that opens to the first valve chamber, a second pilot channel that opens to the second valve chamber, the first pilot channel and the second pilot A communication flow channel communicating with the flow channel, and a pilot supply flow channel communicating the communication flow channel and the pilot pressure working chamber are formed, and the first pilot flow channel and the second pilot flow channel include the Outflow of compressed fluid to communication channel only And first check valve and the second check valve is respectively disposed to allow, in the body, the reservoir portion of compressed fluid that has flowed out to the communication passage communicated with said communication passage is stored The volume of the storage portion formed is larger than the maximum volume of the pilot pressure working chamber .

An internal pilot type three-port switching valve that solves the above problems has a body in which a valve hole that accommodates a spool valve body so as to be capable of reciprocating movement is formed, and the body communicates with the valve hole, and the spool In the axial direction of the valve body, it has a first port, a second port, and a third port arranged in order from one end side to the other end side, and a pilot pressure working chamber is provided on the end side of the spool valve body in the body. A first valve seat on which the first valve portion of the spool valve body is seated is provided between the first port and the second port on the inner peripheral surface of the valve hole, and the second port; A second valve seat on which the second valve portion of the spool valve body is seated is provided between the pilot port and the third port, and the pilot fluid is supplied to the pilot pressure working chamber by supplying electric power to the solenoid portion of the pilot valve portion. Is The internal pilot type three-port switching valve in which the spool valve body is moved to one end side, wherein the first valve portion and the second valve portion are the first valve seat and the second valve portion in the valve hole. A first pilot flow path that is accommodated in a valve chamber provided between the valve seat and that opens closer to one axial end of the spool valve body than the first valve seat in the valve hole. And a second pilot passage that opens closer to the other axial end of the spool valve body than the second valve seat in the valve hole, and communicates with the first pilot passage and the second pilot passage. A communication channel, and a pilot supply channel that communicates the communication channel and the pilot pressure working chamber are formed, and the first pilot channel and the second pilot channel are connected to the communication channel. First that allows only compressed fluid outflow And check valve and the second check valve is respectively disposed, in the body, reservoir for compressed fluid that has flowed out to the communication passage communicated with said communication passage is stored are formed, the reservoir The volume of the part is larger than the maximum volume of the pilot pressure working chamber .

  In the internal pilot type three-port switching valve, the body has a downstream side in the flow direction of the compressed fluid with respect to the first check valve and the second check valve, and more than the pilot valve portion. It is preferable that a pilot pressure discharge portion that can discharge the compressed fluid remaining on the upstream side in the flow direction of the compressed fluid to the outside is provided.

  According to the present invention, one type of switching valve can be used for a normally closed type, a normally open type, and an A / B output type.

(A) is sectional drawing which shows the internal pilot type 3 port switching valve in 1st Embodiment, (b) is a cross section which shows the internal pilot type 3 port switching valve which shows the state by which supply of the electric power to a solenoid part was stopped. Figure. (A) is sectional drawing which shows the internal pilot type | mold 3 port switching valve which shows the state in which the electric power supply to the solenoid part is performed, (b) is an internal which shows the state in which the electric power supply to the solenoid part was stopped Sectional drawing which shows a pilot type 3 port switching valve. (A) is sectional drawing which shows the internal pilot type | mold 3 port switching valve which shows the state in which the electric power supply to the solenoid part is performed, (b) is an internal which shows the state in which the electric power supply to the solenoid part was stopped Sectional drawing which shows a pilot type 3 port switching valve. (A) is sectional drawing which shows the internal pilot type 3 port switching valve in 2nd Embodiment, (b) is a cross section which shows the internal pilot type 3 port switching valve which shows the state by which the electric power supply to the solenoid part was stopped Figure. (A) is sectional drawing which shows the internal pilot type | mold 3 port switching valve which shows the state in which the electric power supply to the solenoid part is performed, (b) is an internal which shows the state in which the electric power supply to the solenoid part was stopped Sectional drawing which shows a pilot type 3 port switching valve. (A) is sectional drawing which shows the internal pilot type | mold 3 port switching valve which shows the state in which the electric power supply to the solenoid part is performed, (b) is an internal which shows the state in which the electric power supply to the solenoid part was stopped Sectional drawing which shows a pilot type 3 port switching valve. (A) And (b) is sectional drawing which shows the internal pilot type | mold 3 port switching valve in another embodiment. (A) And (b) is sectional drawing which shows the internal pilot type | mold 3 port switching valve in another embodiment.

(First embodiment)
A first embodiment embodying an internal pilot type 3-port switching valve will be described below with reference to FIGS. The internal pilot type 3 port switching valve of this embodiment controls the driving of the fluid pressure device by supplying a compressed fluid such as compressed air to the fluid pressure device such as an air cylinder.

  As shown in FIG. 1A, the internal pilot type three-port switching valve 10 has a body 13 in which a valve hole 12 that accommodates a spool valve body 11 so as to reciprocate is formed. The spool valve body 11 is formed with a first valve portion 11a and a second valve portion 11b that are separated from each other in the axial direction. The diameters of the first valve portion 11 a and the second valve portion 11 b are larger than the shaft diameter of the spool valve body 11.

  The body 13 has a first port 31, a second port 32, and a third port 33 that communicate with the valve hole 12 and are arranged in order from one end side to the other end side in the axial direction of the spool valve body 11. On the inner peripheral surface of the valve hole 12, a first valve seat 12 a on which the first valve portion 11 a is seated is provided between the first port 31 and the second port 32, and the second port 32 and the third port 33 are provided. A second valve seat 12b on which the second valve portion 11b is seated is provided in between. A first valve chamber 14 in which the first valve portion 11 a is accommodated is provided nearer one axial end of the spool valve body 11 than the first valve seat 12 a in the valve hole 12, and a second valve chamber 12 is provided in the valve hole 12. A second valve chamber 15 in which the second valve portion 11b is accommodated is provided closer to the other axial end of the spool valve body 11 than the valve seat 12b. Therefore, the first port 31 and the first valve chamber 14 communicate with each other, and the third port 33 and the second valve chamber 15 communicate with each other.

  A first accommodating chamber 16 is formed on one end side of the spool valve body 11 in the body 13. A space between the first storage chamber 16 and the first port 31 is sealed by one end of the spool valve body 11. A first piston 17 is housed in the first housing chamber 16 so as to be capable of reciprocating. The first piston 17 is attached to one end of the spool valve body 11. A pressure acting chamber 18 is defined in the first storage chamber 16 by the first piston 17.

  A second storage chamber 19 is formed on the other end side of the spool valve body 11 in the body 13. The space between the second storage chamber 19 and the third port 33 is sealed by the other end of the spool valve body 11. A second piston 20 is accommodated in the second storage chamber 19 so as to be able to reciprocate. The second piston 20 is attached to the other end portion of the spool valve body 11. The outer diameter of the second piston 20 is larger than the outer diameter of the first piston 17. A pilot pressure working chamber 21 is defined in the second storage chamber 19 by the second piston 20.

  The body 13 is formed with a first pilot channel 34 that opens to the first valve chamber 14 and a second pilot channel 35 that opens to the second valve chamber 15. The body 13 is formed with a communication channel 36 communicating with the first pilot channel 34 and the second pilot channel 35. The communication flow path 36 extends along the axial direction of the spool valve body 11. In the body 13, a flow path 37 that connects one end of the communication flow path 36 and the pressure working chamber 18 is formed. In the body 13, a pilot supply flow path 38 that connects the other end of the communication flow path 36 and the pilot pressure working chamber 21 is formed. A compressed fluid is always supplied to the pressure working chamber 18 from the communication channel 36 via the channel 37.

  The internal pilot type 3 port switching valve 10 has a pilot valve portion 40 provided on the pilot supply flow path 38. The internal pilot type 3-port switching valve 10 is a so-called single pilot type in which one pilot valve portion 40 is provided. The pilot valve section 40 includes a solenoid section 40a (indicated by a broken line in FIG. 1A) that controls the pilot pressure. The pilot valve unit 40 is a known electromagnetic valve that opens when power is supplied to the solenoid unit 40a and closes when power supply to the solenoid unit 40a is stopped. When the pilot valve unit 40 is opened, supply of compressed fluid (pilot fluid) from the pilot supply channel 38 to the pilot pressure working chamber 21 is allowed, and when the pilot valve unit 40 is closed, the pilot supply channel 38 is closed. , The supply of the compressed fluid to the pilot pressure working chamber 21 is shut off.

  A first check valve 51 that allows only the outflow of the compressed fluid to the communication flow path 36 is disposed in the first pilot flow path 34. The second pilot channel 35 is provided with a second check valve 52 that allows only compressed fluid to flow out to the communication channel 36. The first check valve 51 and the second check valve 52 have lip seals 51s and 52s having a V-shaped cross section.

  When the pressure closer to the valve hole 12 than the lip seals 51s and 52s is lower than the pressure closer to the communication flow path 36 than the lip seals 51s and 52s, the first pilot flow path is caused by the lip seals 51s and 52s. The communication between the valve hole 12 and the communication flow path 36 via the 34 or the second pilot flow path 35 is blocked. On the other hand, when the pressure closer to the valve hole 12 than the lip seals 51 s and 52 s exceeds the pressure closer to the communication flow path 36 than the lip seals 51 s and 52 s, the lip seals 51 s and 52 s contract and communicate from the valve hole 12. Outflow of the compressed fluid to the flow path 36 is allowed.

  In the body 13, a storage portion 53 that communicates with the communication flow path 36 is formed. The reservoir 53 stores the compressed fluid that has flowed out to the communication channel 36. The volume of the reservoir 53 is larger than the maximum volume of the pilot pressure working chamber 21. The maximum volume of the pilot pressure working chamber 21 is the volume of the pilot pressure working chamber 21 when the second piston 20 moves closest to the first housing chamber 16 in the second housing chamber 19.

Next, the operation of the first embodiment will be described.
For example, the first port 31 is a supply port connected to the compressed fluid supply source 60, the second port 32 is an output port connected to the fluid pressure device 61, and the third port 33 is connected to the outside. This is a discharge port. In this case, the compressed fluid that has flowed into the first pilot flow path 34 from the first port 31 via the first valve chamber 14 pushes away the lip seal 51 s of the first check valve 51, and the communication flow path 36 and the flow path 37. And always flows out to the pilot supply flow path 38.

  When electric power is supplied to the solenoid unit 40a, the compressed fluid is supplied from the pilot supply flow path 38 to the pilot pressure working chamber 21, and the spool valve is caused by the difference in pressure receiving area between the first piston 17 and the second piston 20. The body 11 moves to one end side. Then, the first valve portion 11a is separated from the first valve seat 12a and the second valve portion 11b is seated on the second valve seat 12b. As a result, the first port 31 and the second port 32 communicate with each other, and the compressed fluid is supplied to the fluid pressure device 61 via the second port 32.

  As shown in FIG. 1B, when the supply of power to the solenoid unit 40a is stopped, the supply of compressed fluid from the pilot supply flow path 38 to the pilot pressure working chamber 21 is interrupted. Then, due to the pressure in the pressure working chamber 18, the spool valve body 11 moves to the other end side, the first valve portion 11a is seated on the first valve seat 12a, and the second valve portion 11b is moved from the second valve seat 12b. Separate. As a result, the first port 31 and the second port 32 are disconnected, and the supply of the compressed fluid to the fluid pressure device 61 via the second port 32 is blocked. Therefore, the internal pilot type 3 port switching valve 10 configured as described above is used as a normally closed type by using the first port 31 as a supply port, the second port 32 as an output port, and the third port 33 as a discharge port. Is done.

  As shown in FIG. 2A, for example, the first port 31 is a discharge port, the second port 32 is an output port, and the third port 33 is a supply port. In this case, the compressed fluid that has flowed from the third port 33 into the second pilot flow path 35 through the second valve chamber 15 pushes away the lip seal 52s of the second check valve 52, thereby causing the communication flow path 36 and the flow path 37. And always flows out to the pilot supply flow path 38.

  When electric power is supplied to the solenoid unit 40a, the compressed fluid is supplied from the pilot supply flow path 38 to the pilot pressure working chamber 21, and the spool valve is caused by the difference in pressure receiving area between the first piston 17 and the second piston 20. The body 11 moves to one end side. Then, the first valve portion 11a is separated from the first valve seat 12a and the second valve portion 11b is seated on the second valve seat 12b. As a result, the second port 32 and the third port 33 are disconnected, and the supply of the compressed fluid to the fluid pressure device 61 via the second port 32 is interrupted.

  As shown in FIG. 2B, when the supply of power to the solenoid unit 40a is stopped, the supply of compressed fluid from the pilot supply flow path 38 to the pilot pressure working chamber 21 is interrupted. Then, due to the pressure in the pressure working chamber 18, the spool valve body 11 moves to the other end side, the first valve portion 11a is seated on the first valve seat 12a, and the second valve portion 11b is moved from the second valve seat 12b. Separate. As a result, the second port 32 and the third port 33 communicate with each other, and the compressed fluid is supplied to the fluid pressure device 61 via the second port 32. Therefore, the internal pilot type 3-port switching valve 10 having the above configuration is used as a normally open type by using the first port 31 as a discharge port, the second port 32 as an output port, and the third port 33 as a supply port. Is done.

  Electric power is supplied to the solenoid unit 40a, and compressed fluid is supplied from the pilot supply flow path 38 to the pilot pressure working chamber 21. Due to the difference in pressure receiving area between the first piston 17 and the second piston 20, the spool valve During the movement of the body 11 to the one end side, the supply port and the discharge port communicate with each other via the valve hole 12. For this reason, there is a compressed fluid flowing between the supply port and the discharge port via the valve hole 12, and the flow rate of the compressed fluid flowing out to the communication flow path 36 is reduced. At this time, since the compressed fluid having a volume larger than the maximum volume of the pilot pressure working chamber 21 is stored in the storage unit 53, the compressed fluid stored in the storage unit 53 is piloted via the pilot supply channel 38. By being supplied to the pressure acting chamber 21, the spool valve body 11 is smoothly moved to one end side.

  As shown in FIG. 3A, for example, the first port 31 is a first output port, the second port 32 is a supply port, and the third port 33 is a second output port. In this case, the compressed fluid from the second port 32 includes the valve portions 11a and 11b that are not seated on the first valve seat 12a or the second valve seat 12b and the valve portions of the first valve portion 11a and the second valve portion 11b. Passing between the seats 12a and 12b, the lip seals 51s and 52s of the first check valve 51 or the second check valve 52 are pushed away to always flow out to the communication flow path 36, the flow path 37 and the pilot supply flow path 38. Is done.

  When electric power is supplied to the solenoid unit 40a, the compressed fluid is supplied from the pilot supply flow path 38 to the pilot pressure working chamber 21, and the spool valve is caused by the difference in pressure receiving area between the first piston 17 and the second piston 20. The body 11 moves to one end side. Then, the first valve portion 11a is separated from the first valve seat 12a and the second valve portion 11b is seated on the second valve seat 12b. As a result, the first port 31 and the second port 32 communicate with each other, and the compressed fluid is supplied to the fluid pressure device 61 via the first port 31.

  As shown in FIG. 3B, when the supply of electric power to the solenoid unit 40a is stopped, the supply of the compressed fluid from the pilot supply passage 38 to the pilot pressure working chamber 21 is interrupted. Then, due to the pressure in the pressure working chamber 18, the spool valve body 11 moves to the other end side, the first valve portion 11a is seated on the first valve seat 12a, and the second valve portion 11b is moved from the second valve seat 12b. Separate. As a result, the second port 32 and the third port 33 communicate with each other, and the compressed fluid is supplied to the fluid pressure device 61 via the third port 33. Therefore, by setting the first port 31 as the first output port, the second port 32 as the supply port, and the third port 33 as the second output port, the internal pilot type three-port switching valve 10 having the above configuration can be -Used as B output type.

  Electric power is supplied to the solenoid unit 40a, and compressed fluid is supplied from the pilot supply flow path 38 to the pilot pressure working chamber 21. Due to the difference in pressure receiving area between the first piston 17 and the second piston 20, the spool valve During the movement of the body 11 to the one end side, the first output port and the second output port communicate with each other through the valve hole 12. For this reason, the compressed fluid that flows between the first output port and the second output port exists via the valve hole 12, and the flow rate of the compressed fluid that flows out to the communication flow path 36 decreases. At this time, since the compressed fluid having a volume larger than the maximum volume of the pilot pressure working chamber 21 is stored in the storage unit 53, the compressed fluid stored in the storage unit 53 is piloted via the pilot supply channel 38. By being supplied to the pressure acting chamber 21, the spool valve body 11 is smoothly moved to one end side.

In the first embodiment, the following effects can be obtained.
(1) The body 13 includes a first pilot channel 34 that opens to the first valve chamber 14, a second pilot channel 35 that opens to the second valve chamber 15, a first pilot channel 34, and a second pilot A communication flow path 36 communicating with the flow path 35 and a pilot supply flow path 38 communicating the communication flow path 36 and the pilot pressure working chamber 21 are formed. The first pilot channel 34 and the second pilot channel 35 are provided with a first check valve 51 and a second check valve 52 that allow only the compressed fluid to flow out to the communication channel 36, respectively. . According to this, it is possible to correspond to a normally closed type, a normally open type, and an A / B output type with a single type of switching valve.

  (2) The body 13 is formed with a storage portion 53 that communicates with the communication flow path 36 and stores the compressed fluid that has flowed into the communication flow path 36. According to this, the compressed fluid stored in the storage portion 53 is supplied to the pilot pressure working chamber 21 via the pilot supply flow path 38, so that the spool valve body 11 moves smoothly to one end side. Is called.

  (3) The first valve portion 11a is housed in the first valve chamber 14 provided closer to one axial end of the spool valve body 11 than the first valve seat 12a in the valve hole 12, and the second valve portion 11 b is accommodated in a second valve chamber 15 provided closer to the other axial end of the spool valve body 11 than the second valve seat 12 b in the valve hole 12. According to this, compared with the case where the 1st valve part 11a and the 2nd valve part 11b are accommodated between the 1st valve seat 12a and the 2nd valve seat 12b in the valve hole 12, the valve hole 12 is provided. The space between the first valve seat 12a and the second valve seat 12b can be shortened. Therefore, the length along the axial direction of the spool valve body 11 in the internal pilot type three-port switching valve 10 can be shortened, and the size can be reduced.

(Second Embodiment)
Hereinafter, a second embodiment in which the internal pilot type 3-port switching valve is embodied will be described with reference to FIGS. In the embodiment described below, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the redundant description thereof is omitted or simplified.

  4A, in the axial direction of the spool valve body 11, the first valve portion 11a and the second valve are provided between the first valve seat 12a and the second valve seat 12b in the valve hole 12. A valve chamber 22 in which the portion 11b is accommodated is provided. The first pilot flow path 34 opens to the first communication chamber 14 </ b> A closer to one axial end of the spool valve body 11 than the first valve seat 12 a in the valve hole 12. The second pilot flow path 35 opens to the second communication chamber 15 </ b> A closer to the other axial end of the spool valve body 11 than the second valve seat 12 b in the valve hole 12. Therefore, the first port 31 and the first communication chamber 14A communicate with each other, and the third port 33 and the second communication chamber 15A communicate with each other.

Next, the operation of the second embodiment will be described.
For example, the first port 31 is a supply port, the second port 32 is an output port, and the third port 33 is a discharge port. In this case, the compressed fluid that has flowed into the first pilot flow path 34 from the first port 31 via the first communication chamber 14 </ b> A pushes away the lip seal 51 s of the first check valve 51, and the communication flow path 36 and the flow path 37. And always flows out to the pilot supply flow path 38.

  When electric power is supplied to the solenoid unit 40a, the compressed fluid is supplied from the pilot supply flow path 38 to the pilot pressure working chamber 21, and the spool valve is caused by the difference in pressure receiving area between the first piston 17 and the second piston 20. The body 11 moves to one end side. Then, the first valve portion 11a is seated on the first valve seat 12a and the second valve portion 11b is separated from the second valve seat 12b. As a result, the first port 31 and the second port 32 are disconnected, and the supply of the compressed fluid to the fluid pressure device 61 via the second port 32 is blocked.

  As shown in FIG. 4B, when the supply of power to the solenoid unit 40a is stopped, the supply of compressed fluid from the pilot supply flow path 38 to the pilot pressure working chamber 21 is interrupted. Then, due to the pressure in the pressure working chamber 18, the spool valve body 11 moves to the other end side, the first valve portion 11a is separated from the first valve seat 12a, and the second valve portion 11b is moved to the second valve seat 12b. Sit down. As a result, the first port 31 and the second port 32 communicate with each other, and the compressed fluid is supplied to the fluid pressure device 61 via the second port 32. Therefore, the internal pilot type three-port switching valve 10 having the above configuration is used as a normally open type by using the first port 31 as a supply port, the second port 32 as an output port, and the third port 33 as a discharge port. Is done.

  As shown in FIG. 5A, for example, the first port 31 is a discharge port, the second port 32 is an output port, and the third port 33 is a supply port. In this case, the compressed fluid that has flowed into the second pilot flow path 35 from the third port 33 through the second communication chamber 15A pushes away the lip seal 52s of the second check valve 52, thereby causing the communication flow path 36 and the flow path 37. And always flows out to the pilot supply flow path 38.

  When electric power is supplied to the solenoid unit 40a, the compressed fluid is supplied from the pilot supply flow path 38 to the pilot pressure working chamber 21, and the spool valve is caused by the difference in pressure receiving area between the first piston 17 and the second piston 20. The body 11 moves to one end side. Then, the first valve portion 11a is seated on the first valve seat 12a and the second valve portion 11b is separated from the second valve seat 12b. As a result, the second port 32 and the third port 33 communicate with each other, and the compressed fluid is supplied to the fluid pressure device 61 via the second port 32.

  As shown in FIG. 5B, when the supply of electric power to the solenoid unit 40a is stopped, the supply of compressed fluid from the pilot supply passage 38 to the pilot pressure working chamber 21 is interrupted. Then, due to the pressure in the pressure working chamber 18, the spool valve body 11 moves to the other end side, the first valve portion 11a is separated from the first valve seat 12a, and the second valve portion 11b is moved to the second valve seat 12b. Sit down. As a result, the second port 32 and the third port 33 are disconnected, and the supply of the compressed fluid to the fluid pressure device 61 via the second port 32 is interrupted. Therefore, the internal pilot type 3-port switching valve 10 having the above configuration is used as a normally closed type by using the first port 31 as a discharge port, the second port 32 as an output port, and the third port 33 as a supply port. Is done.

  As shown in FIG. 6A, for example, the first port 31 is a first output port, the second port 32 is a supply port, and the third port 33 is a second output port. In this case, the compressed fluid from the second port 32 includes the valve portions 11a and 11b that are not seated on the first valve seat 12a or the second valve seat 12b and the valve portions of the first valve portion 11a and the second valve portion 11b. Passing between the seats 12a and 12b, the lip seals 51s and 52s of the first check valve 51 or the second check valve 52 are pushed away to always flow out to the communication flow path 36, the flow path 37 and the pilot supply flow path 38. Is done.

  When electric power is supplied to the solenoid unit 40a, the compressed fluid is supplied from the pilot supply flow path 38 to the pilot pressure working chamber 21, and the spool valve is caused by the difference in pressure receiving area between the first piston 17 and the second piston 20. The body 11 moves to one end side. Then, the first valve portion 11a is seated on the first valve seat 12a and the second valve portion 11b is separated from the second valve seat 12b. As a result, the second port 32 and the third port 33 communicate with each other, and the compressed fluid is supplied to the fluid pressure device 61 via the third port 33.

  As shown in FIG. 6B, when the supply of electric power to the solenoid unit 40a is stopped, the supply of compressed fluid from the pilot supply flow path 38 to the pilot pressure working chamber 21 is interrupted. Then, due to the pressure in the pressure working chamber 18, the spool valve body 11 moves to the other end side, the first valve portion 11a is separated from the first valve seat 12a, and the second valve portion 11b is moved to the second valve seat 12b. Sit down. As a result, the first port 31 and the second port 32 communicate with each other, and the compressed fluid is supplied to the fluid pressure device 61 via the first port 31. Therefore, by setting the first port 31 as the first output port, the second port 32 as the supply port, and the third port 33 as the second output port, the internal pilot type three-port switching valve 10 having the above configuration can be -Used as B output type. Therefore, according to the second embodiment, the same effects as the effects (1) and (2) of the first embodiment can be obtained.

In addition, you may change each said embodiment as follows.
As shown in FIG. 7A, the body 13 has a through hole 13h that communicates the first storage chamber 16 with the outside, and a columnar pilot pressure discharge button 55 is inserted into the through hole 13h. Also good. The through hole 13 h extends along the axial direction of the spool valve body 11. An annular seal member 55 s that seals between the first storage chamber 16 and the outside is mounted on the outer peripheral surface of the pilot pressure discharge button 55. In addition, a plurality of groove portions 55 a are formed on the outer peripheral surface of the pilot pressure discharge button 55 on the side opposite to the first storage chamber 16 from the seal member 55 s. One end of each groove 55a opens to the outside, and the other end is closed before the seal member 55s. A biasing spring 25 is interposed between the first piston 17 and the pilot pressure discharge button 55.

  In the internal pilot type three-port switching valve 10 of each of the above embodiments, when the supply of power to the solenoid unit 40a is stopped and the supply of compressed fluid from the supply source 60 is shut off, the pilot valve unit 40 is While the valve is closed, the communication between the valve hole 12 and the communication flow path 36 is blocked by the first check valve 51 and the second check valve 52. For this reason, the compressed fluid is disposed downstream of the first check valve 51 and the second check valve 52 in the flow direction of the compressed fluid and upstream of the pilot valve portion 40 in the flow direction of the compressed fluid. Remains.

  As shown in FIG. 7B, for example, when maintenance or the like of the internal pilot type 3-port switching valve 10 is performed, the seal member 55s is opposed to the urging force of the urging spring 25 so that the first accommodating chamber 16 has the sealing member 55s. The pilot pressure discharge button 55 is pushed in from the outside until it is located inside and the other end of each groove part 55a is located in the first storage chamber 16. At this time, the pilot pressure discharge button 55 contacts the first piston 17. Then, by continuing to push in the pilot pressure discharge button 55, the first storage chamber 16 and each groove portion 55a communicate with each other, and the compressed fluid flows more than the first check valve 51 and the second check valve 52. The compressed fluid remaining downstream in the direction and upstream of the pilot valve portion 40 in the flow direction of the compressed fluid is discharged to the outside through the grooves 55a. When the operation of pushing the pilot pressure discharge button 55 is released, the pilot pressure discharge button 55 is returned to the position before the pilot pressure discharge button 55 is pushed by the urging force of the urging spring 25.

  As a result, during maintenance of the internal pilot type three-port switching valve 10, the pilot valve portion 40 is located downstream of the first check valve 51 and the second check valve 52 in the flow direction of the compressed fluid and the pilot valve portion 40 The compressed fluid remaining on the upstream side in the flow direction of the compressed fluid can be discharged to the outside. Therefore, the pilot pressure discharge button 55 is located downstream of the first check valve 51 and the second check valve 52 in the flow direction of the compressed fluid and in the flow direction of the compressed fluid from the pilot valve portion 40. It functions as a pilot pressure discharge part that can discharge the compressed fluid remaining on the upstream side to the outside.

  Further, as shown in FIG. 8A, the first piston 17 is deleted, and an urging spring 25 that urges the spool valve body 11 toward the second accommodating chamber 19 in the first accommodating chamber 16. May be accommodated. When the supply of electric power to the solenoid unit 40a is stopped and the supply of the compressed fluid from the pilot supply passage 38 to the pilot pressure working chamber 21 is interrupted, the urging force of the urging spring 25 causes the spool valve body. 11 may move to the other end side. In this case, the urging spring 25 is interposed between the spool valve body 11 and the pilot pressure discharge button 55.

  As shown in FIG. 8B, for example, when maintenance or the like of the internal pilot type 3-port switching valve 10 is performed, the seal member 55s is opposed to the urging force of the urging spring 25 and the first accommodating chamber 16 The pilot pressure discharge button 55 is pushed in from the outside until it is located inside and the other end of each groove part 55a is located in the first storage chamber 16. At this time, the pilot pressure discharge button 55 contacts the spool valve body 11. Then, by continuing to push in the pilot pressure discharge button 55, the first storage chamber 16 and each groove portion 55a communicate with each other, and the compressed fluid flows more than the first check valve 51 and the second check valve 52. The compressed fluid remaining downstream in the direction and upstream of the pilot valve portion 40 in the flow direction of the compressed fluid is discharged to the outside through the grooves 55a. When the operation of pushing the pilot pressure discharge button 55 is released, the pilot pressure discharge button 55 is returned to the position before the pilot pressure discharge button 55 is pushed by the urging force of the urging spring 25.

  In the above embodiments, the first piston 17 and the flow path 37 may be deleted. In this case, an energizing spring that energizes the spool valve body 11 toward the second accommodating chamber 19 is accommodated in the first accommodating chamber 16. When the supply of power to the solenoid unit 40a is stopped and the supply of the compressed fluid from the pilot supply passage 38 to the pilot pressure working chamber 21 is interrupted, the spool valve body 11 is applied by the urging force of the urging spring. May move to the other end side.

  In the above embodiments, the configurations of the first check valve 51 and the second check valve 52 may be changed as appropriate. For example, a check valve configured by a valve member and a spring that biases the valve member toward the valve hole 12 is used, and the compression that has flowed into the first pilot flow path 34 and the second pilot flow path 35 from the valve hole 12. The fluid may push the valve member against the biasing force of the spring to allow the compressed fluid to flow out to the communication channel 36.

In each of the above embodiments, the compressed fluid supplied to the fluid pressure device 61 is not limited to compressed air, and may be other fluids as long as it is a compressed fluid.

  DESCRIPTION OF SYMBOLS 10 ... Internal pilot type 3 port switching valve, 11 ... Spool valve body, 11a ... 1st valve part, 11b ... 2nd valve part, 12 ... Valve hole, 12a ... 1st valve seat, 12b ... 2nd valve seat, 13 ... Body, 14 ... First valve chamber, 15 ... Second valve chamber, 21 ... Pilot pressure working chamber, 22 ... Valve chamber, 31 ... First port, 32 ... Second port, 33 ... Third port, 34 ... First DESCRIPTION OF SYMBOLS 1 pilot flow path, 35 ... 2nd pilot flow path, 36 ... Communication flow path, 38 ... Pilot supply flow path, 40 ... Pilot valve part, 40a ... Solenoid part, 51 ... 1st check valve, 52 ... 2nd reverse Stop valve, 53... Storage section, 55... Pilot pressure discharge button that functions as a pilot pressure discharge section.

Claims (3)

A body formed with a valve hole for reciprocally accommodating the spool valve body, the body communicating with the valve hole and extending from one end side to the other end side in the axial direction of the spool valve body; The first port, the second port, and the third port are arranged in order, and a pilot pressure working chamber is provided on an end portion side of the spool valve body in the body. A first valve seat on which the first valve portion of the spool valve body is seated is provided between the 1 port and the second port, and the spool valve body is provided between the second port and the third port. A second valve seat is provided on which the second valve portion is seated, and the pilot fluid is supplied to the pilot pressure working chamber by supplying electric power to the solenoid portion of the pilot valve portion, so that the spool valve body moves to one end side. Internal pyro A door-type 3-port switch valve,
The first valve portion is housed in a first valve chamber provided closer to one axial end of the spool valve body than the first valve seat in the valve hole, and the second valve portion is the valve A first pilot flow path that is accommodated in a second valve chamber provided closer to the other axial end of the spool valve body than the second valve seat in the hole, and that opens to the first valve chamber, A second pilot channel that opens to the second valve chamber, a communication channel that communicates with the first pilot channel and the second pilot channel, and a communication channel that communicates the communication channel and the pilot pressure working chamber. And a first check valve and a second check valve that allow only the compressed fluid to flow out to the communication flow path in the first pilot flow path and the second pilot flow path. Each valve is arranged ,
The body is formed with a reservoir that communicates with the communication channel and stores compressed fluid that has flowed out into the communication channel, and the volume of the reservoir is larger than the maximum volume of the pilot pressure working chamber. internal pilot type 3-port switch valve which is characterized in that it is. A body formed with a valve hole for reciprocally accommodating the spool valve body, the body communicating with the valve hole and extending from one end side to the other end side in the axial direction of the spool valve body; The first port, the second port, and the third port are arranged in order, and a pilot pressure working chamber is provided on an end portion side of the spool valve body in the body. A first valve seat on which the first valve portion of the spool valve body is seated is provided between the 1 port and the second port, and the spool valve body is provided between the second port and the third port. A second valve seat is provided on which the second valve portion is seated, and the pilot fluid is supplied to the pilot pressure working chamber by supplying electric power to the solenoid portion of the pilot valve portion, so that the spool valve body moves to one end side. Internal pyro A door-type 3-port switch valve,
The first valve portion and the second valve portion are accommodated in a valve chamber provided between the first valve seat and the second valve seat in the valve hole, and the body includes the valve A first pilot passage that opens closer to one end of the spool valve body in the axial direction than the first valve seat in the hole; and the other axial end of the spool valve body in the valve hole than the second valve seat. A second pilot channel that opens closer, a communication channel that communicates with the first pilot channel and the second pilot channel, and a pilot supply channel that communicates the communication channel and the pilot pressure working chamber The first pilot flow path and the second pilot flow path are respectively provided with a first check valve and a second check valve that allow only compressed fluid to flow into the communication flow path. Has been
The body is formed with a reservoir that communicates with the communication channel and stores compressed fluid that has flowed out into the communication channel, and the volume of the reservoir is larger than the maximum volume of the pilot pressure working chamber. internal pilot type 3-port switch valve which is characterized in that it is. The body has a downstream side in the flow direction of the compressed fluid relative to the first check valve and the second check valve, and is further upstream in the flow direction of the compressed fluid than the pilot valve portion. The internal pilot type three-port switching valve according to claim 1 or 2 , further comprising a pilot pressure discharge part capable of discharging the remaining compressed fluid to the outside.