JP4974281B2 - Multi-circuit protection valve - Google Patents

Description

  The present invention relates to a multi-circuit protection valve used for an air pressure circuit such as a brake system of a vehicle.

  In vehicles where service brakes, parking brakes, clutches, suspensions or other accessories are operated with air pressure, multi-circuit protection valves, generally four-circuit protection valves, are used to increase the reliability of the air system. The

For example, as shown in FIG. 13, a four-circuit protection valve disclosed in Patent Document 1 includes a first piston valve B1 and a second piston valve B2 in a primary chamber A1 to which compressed air is supplied from a compressed air source. The first output port C1 and the second output port C2 are connected. In addition, the secondary side (output port C1) of the first piston valve B1 and the secondary side (second output port C2) of the second piston valve B2 are respectively supplied with two by the first check valve D1 and the second check valve D2. While being connected to the secondary chamber A2 through a path, the third output port C3 and the fourth output port C4 are connected to the secondary chamber A2 via the third piston valve B3 and the fourth piston valve B4.
JP 2000-264193 A

  Therefore, the air supplied to the primary chamber A1 is sent out to the first output port C1 and the second output port C2 via the first piston valve B1 and the second piston valve B2. At the same time, part of the air sent out from the first piston valve B1 and the second piston valve B2 is sent into the secondary chamber A2 through a supply path by the first check valve D1 and the second check valve D2. The secondary chamber A2 is sent to the third output port C3 through the third check valve D3 and the third piston valve B3, and is sent to the fourth output port C4 through the fourth check valve D4 and the fourth piston valve B4. . In FIG. 13, reference numerals E1, E2 and F1, F2 denote an orifice and a check valve that connect the primary side and the secondary side of the first piston valve B1 and the second piston valve B2.

  Such a 4-circuit protection valve constitutes a part of the air pressure supply mechanism of the vehicle. For example, as shown in FIG. 14, the 4-circuit protection valve supplies compressed air supplied from an air compressor 15 via an air dryer 17. 1 is distributed to four air pressure circuits 19a to 19d. And even if any of these air pressure circuits 19a to 19d has a failure, the protection valve 1 has another failure by closing the piston valve corresponding to the failed air pressure circuit. Function to protect no air pressure circuit.

  The air pressure circuits 19a to 19d have their respective roles. For example, two of the air pressure circuits 19a and 19b are used for the first and second service brakes, another air pressure circuit 19c is used for the parking brake, and the other air pressure circuit 19d is an accessory. It is used for each. At this time, if a pressure reducing valve is arranged on the primary side of each air pressure circuit, compressed air having a pressure value suitable for the application of the air pressure circuit can be stably supplied.

However, it is not preferable to prepare a pressure reducing valve separately from the protection valve and incorporate it in the air pressure circuit because it causes an increase in installation space. In order to reduce the number of devices in the air pressure circuit and to save space, it is preferable to support such a pressure reducing valve in the valve housing of the protection valve, preferably to incorporate it. Patent Document 2 shows such a concept.
EP 0 976 636 B1 publication

  By the way, the air pressure of each air pressure circuit may differ from each other depending on the manufacturer of the vehicle or the type of the vehicle. Therefore, if the pressure reducing valve is supported or built in the protection valve, a protection valve for each different specification must be prepared, which causes a problem that the number of types of products increases.

  The present invention has been made in view of these problems, and an object of the present invention is to provide a technology capable of standardizing a product of the protection valve while adopting a concept of supporting or incorporating a pressure reducing valve in the multi-circuit protection valve. There is.

  The inventor paid attention to a piston type pressure reducing valve. This type of pressure reducing valve can be easily assembled and removed from a storage chamber provided in the valve housing, and can be provided with a pressure reducing function, and can be removed by removing the pressure reducing function. . Accordingly, it is possible to obtain a plurality of output forms required by each air pressure circuit depending on which storage chamber of the valve housing is assembled with a storage chamber corresponding to the maximum number of required pressure reducing valves, and in which storage chamber of the valve housing is assembled. it can.

  In addition, when the air pressures to be output are greatly different from each other, for example, the original pressure on the air dryer side which is the pressure air supply means is an ultra-high pressure of 1200 kPa, whereas the air pressure circuit side has a high pressure of about 980 kPa and a medium pressure of about 830 kPa. In some cases, a low pressure of about 480 kPa is required. If the piston type pressure reducing valve is used to achieve a large pressure reduction in a single stage, a large pressure setting spring must be used, and the pressure reducing valve becomes large. In the present invention, by performing a large pressure reduction over two stages, a relatively small pressure reducing valve is used, and the size of each pressure reducing valve is made the same. Thereby, the sizes of the plurality of accommodating chambers of the valve housing are made uniform. In order to enable two-stage decompression, in the present invention, two of the plurality of storage chambers are connected in series between the input port and one of the output ports.

  A preferred embodiment of the present invention is an example in which a four-circuit protection valve uses three pressure reducing valves, a first pressure reducing valve, a second pressure reducing valve, and a third pressure reducing valve. The four-circuit protection valve of that form includes an input port and four output ports from the first output port to the fourth output port, and is a protection valve that closes as the pressure of the pressure circuit connected to the output port drops. Is a four-circuit protection valve arranged corresponding to each output port, an input chamber connected to the pressure supply means via the input port, and a flow path from the input chamber to the first output port A first protection valve provided corresponding to the first output port, and a second protection valve provided corresponding to the second output port in a flow path from the input chamber to the second output port; , A merging chamber connected to the secondary side of each of the first protection valve and the second protection valve, and a flow path connecting the merging chamber and the secondary side of the first protection valve. The flow to the secondary side of the second protection valve in the flow path connecting the first check valve for blocking the flow to the secondary side of the valve and the junction chamber and the downstream side of the second protection valve A second check valve for blocking, a third protective valve provided corresponding to the third output port in a flow path from the merge chamber to the third output port, and from the merge chamber to the fourth output port. And a fourth protection valve provided corresponding to the fourth output port in the flow path leading to the compression path further provided in the flow path from the input port to the input chamber, and supplied to the input port A first pressure reducing valve for reducing air to a predetermined pressure and supplying the input chamber to the input chamber; a flow path extending from the merging chamber to the third protective valve and the fourth protective valve; Second pressure reduced to a predetermined pressure and supplied to the third protection valve and the fourth protection valve And a pressure valve provided in a flow path extending from the fourth protection valve to the fourth output port, and the compressed air on the secondary side of the fourth protection valve is reduced to a predetermined pressure and supplied to the fourth output port. 3 pressure reducing valves.

  According to the present invention, it is possible to obtain a plurality of forms of output from each output port depending on which storage chamber of the valve housing is assembled with the pressure reducing valve. Therefore, the main parts including the valve housing can be shared for a plurality of products having different output forms, and standardization of the multi-protection valve can be effectively achieved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a circuit diagram of a four-circuit protection valve (hereinafter abbreviated as “valve”) 100 according to an embodiment of the present invention. 2 to 5 are views showing the appearance of the valve 100, FIG. 2 is a front view, FIG. 3 is a rear view, FIG. 4 is a top view and (B) a bottom view, and FIG. It is a left side view and (B) right side view. 6 is a sectional view taken along line 6-6 in FIG. 3, FIG. 7 is a sectional view taken along line 7-7 in FIG. 4, FIG. 8 is a sectional view taken along line 8-8 in FIG. 10 is a sectional view taken along line 10-10 in FIG. 4, FIG. 11 is a sectional view taken along line 11-11 in FIG. 3, and FIG. 12 is a sectional view taken along line 12-12 in FIG.

  First, a circuit configuration of a valve 100 according to an embodiment of the present invention will be described with reference to FIG. The valve 100 generally includes one input port and four output ports. When an air pressure circuit connected to any one of the output ports fails to cause an air leak, the valve 100 accompanies the pressure drop. A protection valve is provided for each output port.

  In FIG. 1, reference numeral 10 denotes a pressure supply means including an air compressor, reference numeral 11 denotes a first service brake circuit as an air pressure circuit, reference numeral 12 denotes a second service brake circuit as an air pressure circuit, and reference numeral 13 denotes an air pressure. A parking brake circuit as a circuit, and reference numeral 14 denotes an auxiliary machine circuit as an air pressure circuit. The pressure supply means 10 is connected to the input port 1 of the valve 100, the first service brake circuit 11 is connected to the first output port 21, the second service brake circuit 12 is connected to the third output port 22, and the parking brake circuit 13 is connected to the second output port 21. The auxiliary circuit 14 is connected to the output port 23 and the fourth output port 24, respectively.

  The input chamber (indicated by reference numeral (a)) is a space connected to the pressure supply means 10 via the input port 1. A first protection valve 2A is provided in the flow path from the input chamber (a) to the first output port 21. Similarly, the second protection valve 2B is provided in the flow path from the input chamber (a) to the second output port 22. Is provided. In addition, a first communication path 56 that bypasses the first protection valve 2 </ b> A and connects the input chamber (a) and the first output port 21 is provided, and an input from the first output port 21 is input to the first communication path 56. A first check valve 3A for blocking air flow to the chamber (a) and a first throttle valve 4A for reducing the flow rate of air from the input chamber (a) to the first output port 21 are provided. . Similarly, a second communication path 57 that bypasses the second protection valve 2B and communicates the input chamber (a) and the second output port 22 is provided, and the second communication path 57 is connected to the second output port 22 from the second output port 22. A second check valve 3B for blocking the flow of air to the input chamber (a) and a second throttle valve 4B for reducing the flow rate of air from the input chamber (a) to the second output port 22; Yes.

  The flow paths branched from the respective secondary sides of the first protection valve 2A and the second protection valve 2B merge at a merge chamber (indicated by reference numeral (b)). The flow path connecting the merge chamber (b) and the secondary side of the first protection valve 2A has a flow from the merge chamber (b) to the secondary side (first output port 21) of the first protection valve 2A. A third check valve 3 </ b> C is provided to prevent this. The flow path connecting the junction chamber (b) and the secondary side of the second protection valve 2B flows from the junction chamber (b) to the downstream side of the second protection valve 2B (second output port 22). A fourth check valve 3D is provided to prevent the above. Further, a third protective valve 2C corresponding to the third output port 23 is provided in the flow path from the merge chamber (b) to the third output port 23. Similarly, the fourth output port is connected to the fourth output port from the merge chamber (b). In the flow path leading to 24, a fourth protection valve 2 </ b> D is provided corresponding to the fourth output port 24.

  Further, the valve 100 includes a bleedback passage 58 that communicates the input chamber (a) and the third output port 23. The bleedback passage 58 includes a fifth check valve 3E that blocks air flow from the input chamber (a) to the third output port 23.

  The valve 100 further includes three piston type pressure reducing valves 5A to 5C. The pressure reducing valves 5A to 5C are arranged on the upstream side or the downstream side of the protection valves 2A to 2D. The first pressure reducing valve 5A is provided in a flow path from the input port 1 to the input chamber (a), and reduces the compressed air supplied to the input port 1 to a predetermined pressure and supplies it to the input chamber (a). The second pressure reducing valve 5B is located on the downstream side. The second pressure reducing valve 5B is provided in a flow path from the junction chamber (b) to the third protection valve 2C and the fourth protection valve 2D, and reduces the compressed air in the junction chamber (b) to a predetermined pressure to provide a third protection. Supply to the valve 2C and the fourth protection valve 2D. Furthermore, the 3rd pressure-reduction valve 5C is located in the downstream. The third pressure reducing valve 5C is provided in a flow path from the fourth protection valve 2D to the fourth output port 24, and reduces the compressed air downstream of the fourth protection valve 2D to a predetermined pressure to the fourth output port 24. Supply.

Hereinafter, the operation of the valve 100 configured as described above will be described.
When the pressure supply means 10 starts when the air pressure in each of the air pressure circuits 11 to 14 and the valve 100 is zero, compressed air is supplied to the input chamber (a) via the input port 1 and the first pressure reducing valve 5A. . When the pressure in the input chamber (a) rises and reaches the opening pressures of the first protection valve 2A and the second protection valve 2B, the first protection valve 2A and the second protection valve 2B are opened, and the compressed air is The first service brake circuit 11 and the second service brake circuit 12 are supplied.

  Here, the first communication path 56 and the second communication path 57 act to open the first protection valve 2A and the second protection valve 2B more quickly. That is, when the pressure difference between the primary side (compressed air input side) and the secondary side (compressed air output side) is large (for example, the downstream pressure of the first protective valve 2A and the second protective valve 2B) The first communication path 56 and the second communication path are slightly lower in the case where the pressure is smaller (for example, when the compressed air is already supplied to the secondary side) than in the case where the compressed air is not supplied to the side). 57 is designed such that compressed air is supplied in advance to the secondary side of the first protection valve 2A and the second protection valve 2B, and the first protection valve 2A and the second protection valve 2B are opened quickly by a lower valve opening pressure. ing.

  When the first protection valve 2A and the second protection valve 2B are opened, the compressed air is supplied to the merging chamber (b) through the third check valve 3C and the fourth check valve 3D. The air pressure in the merge chamber (b) is supplied to the primary side of the third protection valve 2C and the fourth protection valve 2D via the second pressure reducing valve 5B. When the third protective valve 2 </ b> C is opened by the pressure supply, compressed air is supplied to the parking brake circuit 13. When the fourth protection valve 2D is opened, the compressed air is supplied to the auxiliary circuit 14 via the third pressure reducing valve 5C. As described above, the third protection valve 2C and the fourth protection valve 2D are opened after the air pressures of the first service brake circuit 11 and the second service brake circuit 12 reach the minimum pressure at which the service brake can be operated, respectively. Then, pressure is started to be supplied to the parking brake circuit 13 and the auxiliary circuit 14 downstream of them.

In the valve 100 configured as described above, for example, when the first service brake circuit 11 fails in a state where the vehicle is stopped (operating state of the parking brake), the first protection valve 2A is connected to the secondary side and the primary side thereof. Close by pressure drop. Further, since the compressed air in the input chamber (a) flows out through the first communication passage 56 and the pressure in the input chamber (a) decreases, the second protective valve 2B is also closed. Here, the compressed air of the parking brake circuit 13 is directed from the second output port 23 to the first output port 21 via the bleed back passage 58, the input chamber (a), and the first communication passage 56 in this order. The pressure of the parking brake circuit 13 becomes lower than the lowest usable pressure, that is, the parking brake cannot be released. As a result, the third protective valve 2C is also closed.
According to the above, when the first service brake 11 fails, the parking brake cannot be released and the vehicle cannot start, so that a safety problem can be avoided. The same operation is performed when the second service brake circuit 12 fails.

  Next, when the pressure supply means 10 is operated and compressed air is supplied again to the input chamber (a), the pressure of the input chamber (a) can be increased to a predetermined pressure by the action of the first throttle valve 4A. . Here, since the pressure on the secondary side of the first protection valve 2A is remarkably reduced, and the compressed air remains on the secondary side of the second protection valve 2B, the pressure is higher than the valve opening pressure of the first protection valve 2A. The second protective valve 2B opens at a low valve opening pressure, and the second service brake circuit 12 is ready for use. Thereafter, the air pressure in the parking brake circuit 13 and the auxiliary circuit 14 becomes higher than the lowest usable pressure due to the pressure increase in the merge chamber (b), and both air pressure circuits are ready for use.

  The pressure reducing valves 5A to 5C provided on the primary side or the secondary side of the protection valves 2A to 2D operate as follows. The first pressure reducing valve 5 </ b> A disposed on the secondary side of the input port 1 reduces the pressure of the compressed air on the primary side to a pressure suitable for the first service brake circuit 11 and the second service brake circuit 12. The second pressure reducing valve 5B disposed downstream of the first protection valve 2A and the second protection valve 2B and on the secondary side of the merge chamber (b) is suitable for the parking brake circuit 13 with the compressed air on the primary side. Reduce pressure to Further downstream, the third pressure reducing valve 5C disposed on the secondary side of the fourth protection valve 2D reduces the pressure of the compressed air on the primary side to a pressure suitable for the auxiliary circuit 14.

Next, the structure of the valve 100 described above will be described in detail with reference to FIG.
As shown in the external views of FIGS. 2 to 5, the valve main body (valve housing) 30 serving as the base of the valve 100 includes the input port 1 near the center of the front surface 31 and each output port 21 on the rear surface 32. To 24. Covers 45 </ b> A to 45 </ b> D for configuring the protection valves 2 </ b> A to 2 </ b> D are attached to the upper surface 33 of the valve body 30 so as to be aligned in a direction along the front surface 31 of the valve body 30. Two covers 45A and 45B closer to the center are provided corresponding to the first protection valve 2A and the second protection valve 2B. A cover 45C near the left side surface 35 of the valve body 30 is provided corresponding to the third protection valve 2C. Further, a cover 45D near the right side surface 36 is provided corresponding to the fourth protection valve 2D. These covers 45 </ b> A to 45 </ b> D cover openings of holes formed in the upper surface 33 of the valve body 30 in order to dispose the protective valves 2 </ b> A to 2 </ b> D and urge the valve bodies constituting the respective protective valves. The coil spring is accommodated.

Hereinafter, the internal configuration of the valve 100 will be described in more detail with reference to cross-sectional views.
As shown in FIG. 6, the input port 1 is formed from an opening on the front 31 side of a stepped hole 311 drilled so as to penetrate from the front surface 31 to the back surface 32 of the valve body 30. The first pressure reducing valve 5A and the input chamber (a) are provided in the stepped hole 311. Positioned on the bottom surface 34 side with respect to the first pressure reducing valve 5A is the second pressure reducing valve 5B. The second pressure reducing valve 5 </ b> B is provided in a bottomed hole 325 that is formed perpendicularly to the back surface 32 of the valve body 30.

  The input chamber (a) formed by the stepped hole 311 is located near the upper surface 22 near the center of the valve body 30 in FIG. A flow path 351 is provided so as to be perpendicular to the left side surface 35 of the valve body 30 so as to be orthogonal to the stepped hole 311. The input chamber (a) is formed at the intersection between the stepped hole 311 and the flow path 351 that intersect each other. Two bottomed holes 331 and 332 are formed in the upper surface 33 of the valve body 30 so as to reach a flow path 351 extending along the upper surface 33. The first protective valve 2A is disposed inside one bottomed hole 331 located closer to the left side surface 35. The second protective valve 2B is disposed inside the other bottomed hole 332 located near the right side surface 36. In this configuration, the flow path 351 connecting the bottomed holes 331 and 332 serves as a passage connecting the primary side of each of the first protection valve 2A and the second protection valve 2B and the input chamber (a).

  A cover 45 </ b> A is attached so as to cover the opening of one bottomed hole 331 provided on the upper surface 33. A cover 45B is attached so as to cover the opening of the other bottomed hole 332. In one bottomed hole 331, in addition to the first protection valve 2A, a first communication passage 56 that bypasses the first protection valve, a first check valve 3A, and a first throttle valve 4A (in FIG. 1). (Refer to the circuit diagram). In addition to the second protection valve 2B, the other bottomed hole 332 has a second communication passage 57 that bypasses the second protection valve 2B, a second check valve 3B, and a second throttle valve 4B ( 1 (see the circuit diagram of FIG. 1).

  In FIG. 7, the third check valve 3C and the fourth check valve 3D are positioned on the bottom surface 34 side with respect to the first protection valve 2A and the second protection valve 2B. These check valves 3 </ b> C and 3 </ b> D are respectively provided in bottomed holes 341 and 342 that are formed perpendicular to the bottom surface 34 of the valve body 30. In FIG. 7, the valve provided along the right side surface 36 is the third pressure reducing valve 5 </ b> C. The third pressure reducing valve 5 </ b> C is disposed in a bottomed hole 343 that is formed perpendicular to the bottom surface 34 of the valve body 30.

  As shown in FIG. 8, the third check valve 3C located below the first protection valve 2A operates by receiving the air pressure on the secondary side (output port 21) of the first protection valve 2A. The secondary side of the first protection valve 2A (the flow path 331a drilled inside the bottomed hole 331) and the primary side of the third check valve 3C are drilled perpendicular to the back surface 32 of the valve body 30. It is connected through the provided flow path 321. The opening of the flow path 321 forms the first output port 21. Although not shown, the same applies to the other fourth check valve 3D. The secondary side of the second protection valve 2B and the primary side of the fourth check valve 3D are connected to the back surface 32 of the valve body 30. They are connected to each other through a flow path 322 formed vertically. The opening of the flow path 322 forms the second output port 22.

  As shown in FIG. 7, each secondary side of the third check valve 3 </ b> C and the fourth check valve 3 </ b> D has a flow path 352 formed perpendicular to the right side surface 35 near the bottom surface 34 of the valve body 30. Connected by. The flow path 352 is formed so as to intersect with the bottomed holes 341 and 342 extending from the bottom surface 34, and forms a merge chamber (b) between the third check valve 3C and the fourth check valve 3D. ing. As shown in FIG. 6, this flow path 352 also intersects with a bottomed hole 325 drilled from the back surface 32 in order to dispose the second pressure reducing valve 5B. With this configuration, the secondary sides of the third check valve 3C and the fourth check valve 3D are connected to the primary side of the second pressure reducing valve 5B via the junction chamber (b).

  As shown in FIG. 9, the secondary side of the second pressure reducing valve 5 </ b> B is connected to a flow path 353 that is formed perpendicular to the left side surface 35 of the valve body 30. Another flow path 354 is formed in parallel with the flow path 353 on the bottom surface 32 side with respect to the flow path 353. These flow paths 353 and 354 are connected through an oblique hole 391 orthogonal thereto. The skew hole 391 is formed from an inclined surface 39 formed by cutting a part of a corner between the bottom surface 34 and the back surface 32 of the valve body 30 (see FIGS. 3 and 4B). .

  The flow path 354 drilled along the bottom surface 34 is connected to two flow paths 333 and 334 drilled perpendicular to the upper surface 33 of the valve body 30 as shown in FIG. One flow path 333 located near the left side surface 35 of the valve body 30 forms a third protective valve 2C at the opening thereof. The other flow path 334 located closer to the right side surface 36 forms a fourth protection valve 2D at its opening. In this configuration, the primary side (one flow path 333) of the third protection valve 2C and the primary side (the other flow path 334) of the fourth protection valve 2D are a flow path 354 extending along the bottom surface 34, an oblique hole. 391 and the flow path 353 (see FIG. 9), each connected to the secondary side of the second pressure reducing valve 5B.

  The opening of one flow path 333 provided on the upper surface 33 of the valve body 30 is covered with a cover 45C. A diaphragm for forming the third protection valve 2 </ b> C is sandwiched between the cover 45 </ b> C and the valve body 30 together with the opening of the flow path 333. The opening of the other channel 334 is covered with a cover 45D. A diaphragm for forming the fourth protection valve 2 </ b> D is sandwiched between the cover 45 </ b> D and the valve body 30 together with the opening of the flow path 334.

  As shown in FIG. 11, the secondary side of the third protection valve 2 </ b> C (the channel 333 a formed in the upper surface 33 adjacent to the channel 333) penetrates from the back surface 32 of the valve body 30 to the front surface 31. It is connected to the drilled stepped hole 323. An opening on the back surface 32 side of the stepped hole 323 forms a third output port 23. On the other hand, a fifth check valve 3E (see the circuit diagram of FIG. 1) is disposed inside the stepped hole 323 on the front 31 side. The fifth check valve 3E operates by receiving the air pressure on the secondary side (third output port 23) of the third protection valve 2C. The stepped hole 323 in which the fifth check valve 3E is disposed intersects a flow path 351 (see FIG. 7) drilled from the left side surface 35 of the valve body 30. With this structure, the stepped hole 351 has a bleedback passage 58 (see the circuit diagram of FIG. 1) that connects the secondary side (third output port 23) of the third protection valve 2C and the input chamber (a). Forming.

  As shown in FIG. 12, the secondary side of the fourth protection valve 2 </ b> D (the channel 334 a drilled in the upper surface 33 adjacent to the channel 334) is drilled perpendicular to the bottom surface 34 of the valve body 30. It is connected to the bottomed hole 343. A third pressure reducing valve 5C is disposed inside the bottomed hole 343. With this configuration, the secondary side of the fourth protection valve 2D and the primary side of the third pressure reducing valve 5C are connected. The secondary side of the third pressure reducing valve 5 </ b> C is connected to a flow path 324 that is drilled perpendicularly to the back surface 32 of the valve body 30. The opening of the flow path 324 forms the opening of the fourth output port 24.

  As described above, in the valve 100 shown in this embodiment, the protection valves 2 </ b> A to 2 </ b> D are arranged on the upper surface 33 of the valve body 30 in the direction along the front surface 31. Among them, the third check valve 3C and the fourth check valve 3D connected to the respective secondary sides of the first protection valve 2A and the second protection valve 2B closer to the center are the first protection valve 2A and the second check valve 3D. 2 The valve body 30 is disposed in a space on the bottom surface 34 side with respect to the protective valve 2B. Further, the first pressure reducing valve 5A and the second pressure reducing valve 5B arranged on the upstream side and the downstream side with respect to the first protection valve 2A and the second protection valve 2B are arranged in the vertical direction (upper surface 33) near the center of the valve body 30. In the direction from the bottom 34 to the bottom 34) and arranged so as not to contact the other first protection valve 2A, second protection valve 2B, third check valve 3C and fourth check valve 3D. . Further, the fifth check valve 3E connected to the secondary side of the third protection valve 2C is disposed in a space on the bottom surface 34 side of the valve body 30 with respect to the third protection valve 2C. The third pressure reducing valve 5C connected to the secondary side of the fourth protection valve 5D is disposed in a space on the bottom surface 34 side of the valve body 30 with respect to the fourth protection valve 2D. Thus, the valve 100 arranges each component (each valve) with high space efficiency and suppresses an increase in the size of the valve body 30.

  Furthermore, when the valve 100 shown in this embodiment is used for an air pressure circuit that does not require at least one of the three pressure reducing valves 5A to 5C, a step formed in the valve main body 30 to dispose the pressure reducing valve. This can be dealt with by removing the valve component provided in the inside of the attached hole and airtightly closing the opening of the stepped hole with the lid member.

  FIG. 15 corresponds to FIG. In FIG. 6, the first pressure reducing valve 5 </ b> A and the second pressure reducing valve 5 </ b> B are assembled in the accommodation chambers of the valve housing (the stepped hole 311 and the stepped bottomed hole 325), respectively. On the other hand, in FIG. 16, the lower first pressure reducing valve 5B is removed while the upper first pressure reducing valve 5A is assembled. The second pressure reducing valve 5B is a piston type like the other pressure reducing valves. The main components are a pressure setting piston 504 that receives the force of the pressure setting spring 502 and a valve body 506 that follows the movement of the pressure setting piston 504 (see FIG. 6). The second pressure reducing valve 5 </ b> B assembled in the storage chamber can be easily removed from the storage chamber by removing the lid member 508 that supports the other end of the pressure setting spring 502. Then, after removing the component (or component) of the second pressure reducing valve 5B, another similar lid member 508 'is provided at the opening of the storage chamber. Thereby, the state where the pressure reducing function does not occur can be obtained from the state where the pressure reducing function by the second pressure reducing valve 5B is obtained.

  FIG. 16 is a view corresponding to FIG. 12, and FIG. 12 shows a state where the third pressure reducing valve 5C is assembled, while FIG. 16 shows a state where the third pressure reducing valve 5C is removed. Similarly to the second pressure reducing valve 5B, the third pressure reducing valve 5C can selectively obtain a state where the pressure reducing function is obtained and a state where the pressure reducing function is not generated. Note that the chamber portion in which the pressure setting spring 502, which is a component of the pressure reducing valve, is placed at atmospheric pressure through the atmospheric communication passage. On the other hand, the lid member 508 used when the pressure reducing valve is assembled is provided with an atmosphere communication path, whereas the lid member 508 ′ used when the pressure reducing valve is removed does not have such an atmosphere communication path (hole). Use things.

Regarding the presence or absence of the first to third pressure reducing valves 5A, 5B, and 5C (that is, the attached state and the removed state), various types of variations can be taken as follows.
Pressure reducing valve 5A Pressure reducing valve 5B Pressure reducing valve 5C
(Type 1) Yes Yes Yes (Type 2) Yes Yes No (Type 3) Yes No Yes (Type 4) No Yes Yes (Type 5) Yes No No (Type 6) No Yes No (Type 7) No No Yes ( Type 8) None None None

And according to the variations of such types 1-7, the air pressure of each of the first to fourth output ports 21, 22, 23, 24 is as follows. It should be noted that ultra-high means an ultra-high pressure of about 1200 kPa, high means a high pressure of about 980 kPa, medium means a medium pressure of about 830 kPa, and low means a low pressure of about 480 kPa.
Output port 21/22 Output port 23 Output port 24
(Type 1) High Medium Low (Type 2) High Medium Medium (Type 3) High High Medium (Type 4) Ultra High High Medium (Type 5) High High High (Type 6) Ultra High High High (Type 7) Ultra High Super High High (Type 8) Super High Super High Super High

  Furthermore, FIGS. 17-21 shows the modification of this invention. 17 is FIG. 2, FIG. 18 is FIG. 3, FIG. 19 is FIG. 4 (A), FIG. 20 is FIG. 4 (B), and FIG. In FIGS. 17 to 21, corresponding portions are denoted by the same reference numerals. From these figures, the volume of the valve housing, which is usually molded from aluminum or its alloy, is reduced as much as possible, the material usage and weight are reduced, the cost is reduced, and the left and right sides of the valve layout with respect to the valve housing are left and right. It should be understood that the arrangement can be reversed. Furthermore, as shown in FIG. 21, in the embodiment described above, the flow paths 353 and 354 in the valve housing are provided in parallel and communicated with each other through the oblique flow paths 391. And 354 can be arranged in a straight line so that they can communicate directly. Then, the oblique flow path 391 becomes unnecessary.

1 is a circuit diagram of a four-circuit protection valve according to the present invention. 1 is an external front view of a four-circuit protection valve according to the present invention. The external appearance rear view of the 4 circuit protection valve which concerns on this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is an external view of the 4 circuit protection valve based on this invention, Comprising: (A) is the top view, (B) is the bottom view. It is an external view of the 4-circuit protection valve concerning this invention, (A) is the left view, (B) is the right view. 6-6 sectional drawing of FIG. 7-7 sectional drawing of FIG. 8-8 sectional drawing of FIG. 9-9 sectional drawing of FIG. 5 (A). 10-10 sectional drawing of FIG. 11-11 sectional drawing of FIG. 12-12 sectional drawing of FIG. The circuit diagram of the 4 circuit protection valve based on a prior art. The conceptual diagram of the air pressure supply mechanism of the vehicle which concerns on a prior art. The figure which shows another state corresponding to FIG. The figure which shows another state corresponding to FIG. The figure which shows the deformation | transformation corresponding to FIG. The figure which shows the deformation | transformation corresponding to FIG. The figure which shows the deformation | transformation corresponding to FIG. The figure which shows the deformation | transformation corresponding to FIG. 4 (B). XX sectional drawing of FIG.

Explanation of symbols

1 Input port 2A 1st protection valve 2B 2nd protection valve 2C 3rd protection valve 2D 4th protection valve 3A 1st check valve 3B 2nd check valve 3C 3rd check valve 3D 4th check valve 3E 5th Check valve 4A first throttle valve 4B second throttle valve 5A first pressure reducing valve 5B second pressure reducing valve 5C third pressure reducing valve 10 pressure supply means 11 first service brake circuit 12 second service brake circuit 13 hand brake circuit 14 Machine circuit 21 1st output port 22 2nd output port 23 3rd output port 24 4th output port 30 Valve body (valve housing)
100 4 circuit protection valve 502 pressure setting spring 504 pressure setting piston 504
506 Valve body 508, 508 'cover member

Claims (5)

A multi-circuit protection valve that is connected between the pressure air supply means and the plurality of air pressure circuits, and protects the remaining normal air pressure circuits when at least one of the plurality of air pressure circuits fails. Because
A valve housing comprising an input port to which compressed air is supplied from the compressed air supply means, and at least three output ports for outputting to each of the plurality of air pressure circuits;
A protective valve supported by the valve housing, provided corresponding to each of the plurality of air pressure circuits, and protecting each air pressure circuit;
A pressure reducing valve that is supported by the valve housing and outputs a predetermined pressure required by each air pressure circuit from each output port;
In addition, the multi-circuit protection valve has the following features.
(A) The valve housing includes a plurality of storage chambers for assembling the pressure reducing valve. (B) Two of the storage chambers are connected in series between the input port and one of the output ports. (C) The pressure reducing valve connected is a piston-type valve, and any pressure reducing valve can be assembled to or removed from the accommodating chamber. (D) In any accommodating chamber of the valve housing, Depending on whether a pressure reducing valve is assembled, multiple forms of output from each output port can be obtained. The multi-circuit protection valve is a four-circuit protection valve, and the output ports are four from a first output port to a fourth output port,
An input chamber connected to the pressure supply means via the input port; and a first protection valve provided corresponding to the first output port in a flow path from the input chamber to the first output port; A second protection valve provided corresponding to the second output port in a flow path from the input chamber to the second output port; and a secondary side of each of the first protection valve and the second protection valve; A first check valve for blocking the flow to the secondary side of the first protection valve in the flow path connecting the junction room and the junction chamber and the secondary side of the first protection valve; A second check valve for blocking the flow of the second protection valve to the secondary side in the flow path connecting the junction chamber and the secondary side of the second protection valve; and the third output port from the junction chamber A third protective valve provided corresponding to the third output port in the flow path leading to And a fourth protection valve provided corresponding to said fourth output port in the flow path leading to said fourth output port from the confluent chamber,
A first pressure reducing valve that is provided in a flow path extending from the input port to the input chamber, depressurizes the compressed air supplied to the input port to a predetermined pressure, and supplies the compressed air to the input chamber; A second pressure reducing valve provided in a flow path leading to the third protective valve and the fourth protective valve, and reducing the compressed air in the merging chamber to a predetermined pressure and supplying the compressed air to the third protective valve and the fourth protective valve; A third pressure reducing valve provided in a flow path extending from the fourth protection valve to the fourth output port, wherein the compressed air on the secondary side of the fourth protection valve is reduced to a predetermined pressure and supplied to the fourth output port; The multi-circuit protection valve according to claim 1, comprising:   The multi-circuit protection valve according to claim 1, wherein the storage chamber is a stepped hole having one end closed in the axial direction and the other end opened.   When the pressure reducing valve is assembled, the storage chamber is closed by a lid member that supports a pressure setting spring, and when the pressure reducing valve is removed, the storage chamber is replaced with the lid member. The multi-circuit protection valve of claim 1, wherein the opening is closed by a member.   3. The multi-circuit protection valve according to claim 2, wherein compressed air from the merging chamber toward the fourth output port is depressurized in two stages by the second pressure reducing valve and the third pressure reducing valve.

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