Compressed air supply device

Abstract

To suppress leakage of compressed air.SOLUTION: A compressed air supply device 1 for supplying compressed air to external equipment operating by compressed air includes: a cylinder chamber 201; a rod 21 which is arranged in the cylinder chamber 201 and where a vent hole 213 communicating with a first exhaust port 210a and a first air chamber 201a and a first flow passage 210 which communicates the first exhaust port 210a and the vent hole 213 and in which compressed air flows are formed; and an opening / closing part 22 arranged in the cylinder chamber 201 and for opening / closing the vent hole 213 according to a pressure difference of the first air chamber 201a with respect to a second air chamber 201b. When the opening / closing part 22 according to the pressure difference opens the vent hole 213, the compressed air supplied to the first air chamber 201a flows in the first flow passage 210, is exhausted from the first exhaust port 210a, and is supplied to external equipment.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a compressed air supply device. [Background technology]

[0002] Compressed air supply devices that supply compressed air from an external source to pneumatically operated equipment that operates using compressed air have been known for some time. Patent Document 1 discloses a compressed air supply device that has a protruding piston that moves forward using air pressure and an air supply rod that is provided within the protruding piston and can move forward and backward relative to the protruding piston.

[0003] In the compressed air supply device of Patent Document 1, when a pneumatically operated device mounted on a moving device approaches, the tip of the air inlet rod protrudes beyond the tip of the protruding piston, and the protruding piston and the air inlet rod move together toward the moving device by compressed air supplied from an air supply source. When the tip of the air inlet rod hits the connecting surface of the moving device, the air inlet rod moves backward. The backward movement of the air inlet rod opens an on-off valve, and the supplied compressed air is supplied to the pneumatically operated device through an air guide path formed in the air inlet rod. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-11444 Summary of the Invention [Problem to be solved by the invention]

[0005] In the device of Patent Document 1, the on-off valve is configured to open when the tip of the air supply rod comes into contact with the moving device, which means that the on-off valve may open when airtightness is not ensured between the tip of the air supply rod and the moving device, potentially resulting in a leak of compressed air. [Means for solving the problem]

[0006] A compressed air supply device according to an embodiment is a compressed air supply device that supplies compressed air to an external device that operates with compressed air. The compressed air supply device includes a first air chamber to which compressed air is supplied through a first supply port, a cylinder chamber partitioned into a second air chamber, a rod disposed in the cylinder chamber, having a first exhaust port formed at an end, a vent port communicating with the first air chamber, and a first flow path formed to communicate the first exhaust port and the vent port through which compressed air flows. The compressed air supply device further includes an opening / closing portion disposed in the cylinder chamber that opens or closes the vent port according to a differential pressure between the first air chamber and the second air chamber. When the opening / closing portion opens the vent port according to the differential pressure, the compressed air supplied to the first air chamber flows through the first flow path, is exhausted from the first exhaust port, and is supplied to the external device.

Advantages of the Invention

[0007] According to the present invention, compressed air can be supplied to an external device according to a differential pressure between a first air chamber and a second air chamber.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0009] Hereinafter, a compressed air supply device according to an embodiment will be described in detail with reference to the drawings. The compressed air supply device according to this embodiment can supply a fluid (actuating air) such as compressed air to a pneumatic actuating device (pneumatic device) such as a chuck that grips and positions a workpiece such as a work piece as an external device that operates with compressed air. Note that the compressed air supply device is not limited to being used for the above applications.

[0010] <Overall Configuration> FIG. 1 is an external view of the compressed air supply device 1, FIG. 1(A) is a plan view, and FIG. 1(B) is a side view. Further, FIG. 2 is a cross-sectional view of the compressed air supply device 1. FIG. 2 shows a cross-section of the compressed air supply device 1 taken along line A-A in FIG. 1(A). Note that FIGS. 1 and 2 show the compressed air supply device 1 in an initial state where no compressed air is supplied.

[0011] The compressed air supply device 1 includes a cylinder unit 2 and a relay unit 3. The cylinder unit 2 and the relay unit 3 are arranged along the direction in which the axis L extends and are fixed on the surface of a base member (not shown). Note that the cylinder unit 2 and the relay unit 3 are arranged with a space therebetween.

[0012] As shown in FIGS. 1(A) and 1(B), the cylinder unit 2 has a cylinder tube 20, an air supply pipe port (first supply port) 4 provided on the side wall surface of the cylinder tube 20, and an exhaust pipe port 5. Further, the cylinder unit 2 is provided with a rod 21 in which a first exhaust port, which will be described in detail later, is formed.

[0013] The relay unit 3 is a rectangular body having a facing wall surface 301 facing the cylinder unit 2 and an upper wall surface 302 which is a wall surface different from the facing wall surface 301. An air supply port (second supply port) 6 and an exhaust pipe port (second exhaust port) 7 are provided on the facing wall surface 301. The compressed air supply device 1 according to this embodiment supplies a fluid such as compressed air supplied to the cylinder unit 2 via the first supply port 4 to the external device 100 via the relay unit 3.

[0014] <Cylinder Unit 2> As shown in Fig. 2, the cylinder unit 2 includes a cylinder tube 20, a rod 21, an opening / closing part 22, a holding part 23, a biasing part 24, a collar 25, and a head cover 26.

[0015] <Cylinder tube 20> The cylinder tube 20 is formed in a cylindrical shape with a cylinder chamber 201 formed about an axis L. As shown in Fig. 1(A), the outer shape of the cylinder tube 20 has a long side in a direction parallel to the axis L and a short side in a direction orthogonal to the axis L. In the following description, the direction along the long side of the cylinder tube 20 is referred to as the X direction, the direction along the short side is referred to as the Y direction, and the direction orthogonal to the X and Y directions is referred to as the Z direction. Also, in the X direction, the side of the cylinder tube 20 facing the relay part 3 may be referred to as the + side.

[0016] As shown in Fig. 2, one end 200a of the cylinder tube 20, that is, the X direction - side, is open. The other end 200b of the cylinder tube 20, that is, the X direction + side, has a hole (insertion hole) 202 formed therein that communicates the outside of the cylinder tube 20 with the cylinder chamber 201.

[0017] The diameter of the insertion hole 202 is smaller than the diameter of the cylinder chamber 201. The rod 21, which will be described later, is inserted into the insertion hole 202. A groove is formed on the inner peripheral wall surface of the insertion hole 202, and a seal member 202a, such as a resin material, is disposed in this groove.

[0018] The opening on the X direction - side of the cylinder tube 20 is closed by the head cover 26. The head cover 26 has a diameter substantially equal to the inner diameter of the cylinder tube 20 and is inserted into the opening from the X direction - side of the cylinder tube 20. Then, it is fixed by a retaining ring 206 provided on the X direction - side of the head cover 26. A groove is formed along the outer peripheral wall surface of the head cover 26, and a seal member 261, such as a resin material, is disposed therein.

[0019] The cylinder chamber 201 is partitioned into a first air chamber 201a and a second air chamber 201b. The above-described first supply port 4 communicates the first air chamber 201a on the -X direction side with respect to the opening / closing portion 22 (to be described later) in the cylinder chamber 201 with the outside. That is, compressed air is supplied to the first air chamber 201a via the first supply port 4. Further, the piping port 5 communicates the second air chamber 201b on the +X direction side with respect to the opening / closing portion 22 in the cylinder chamber 201 with the outside.

[0020] <Rod 21> The rod 21 is a hollow member that extends along the X direction and has a first flow path 210 formed therein. The rod 21 is accommodated in the cylinder chamber 201 so as to be reciprocally movable along the X direction. Specifically, a part of the rod 21 on the +X direction side is inserted into the insertion hole 202, and the remaining part is accommodated in the cylinder chamber 201.

[0021] As will be described in detail later, when the rod 21 moves in the +X direction, it protrudes beyond the end portion 200b of the cylinder tube 20 on the +X direction side. When the rod 21 moves in the -X direction from this state, it is accommodated in the cylinder chamber 201 and returns to the initial state shown in FIGS. 1(A), 1(B), and 2. In the following description, the +X direction may be referred to as the protruding direction, and the -X direction may be referred to as the accommodating direction.

[0022] The rod 21 is formed with the above-described first flow path 210, a first exhaust port 210a, and a ventilation port 213. The first flow path 210 is a through hole formed along the X direction around the axis L and penetrating the rod 21. The first flow path 210 is a flow path through which the supplied compressed air flows, as will be described in detail later.

[0023] A collar 25 (to be described later) is attached to the end portion of the rod 21 on the -X direction side. Specifically, a female screw is formed at the opening 210b at the end portion of the first flow path 210 on the -X direction side, and the collar 25 is screw-fastened thereto.

[0024] The first exhaust port 210a is formed at the +X side end of the first flow path 210, that is, at the +X side end 211 of the rod 21, and is an opening through which the compressed air flowing through the first flow path 210 is exhausted. When the rod 21 moves in the +X direction as described later, the first flow path 210 communicates with the second supply port 6 formed in the relay portion 3 through the first exhaust port 210a at the +X side end.

[0025] The vent hole 213 is formed in the outer peripheral wall surface 218 of the rod 21 and communicates the outside of the rod 21 with the first flow path 210. In other words, the first flow path 210 communicates the first exhaust port 210a and the vent hole 213. The vent hole 213 is formed on the side of the first air chamber 201a in the outer peripheral wall surface 218 regardless of the movement of the rod 21 along the X direction. That is, the vent hole 213 communicates with the first air chamber 201a. Further, as shown in FIG. 2, when the compressed air supply device 1 is in the initial state, the vent hole 213 is blocked from the outside of the rod 21 by an opening / closing portion 22 described later.

[0026] The rod 21 is formed by a first portion 214 and a second portion 215 having different outer diameters. The first portion 214 is the +X side portion of the rod 21, and its outer diameter is substantially equal to the diameter of the insertion hole 202. That is, the first portion 214 of the rod 21 is inserted into the insertion hole 202. The second portion 215 is formed on the -X side with respect to the first portion 214, and its outer diameter is smaller than the outer diameter of the first portion 214. Therefore, a stepped portion 216 is formed at the boundary between the first portion 214 and the second portion 215.

[0027] <Color 25> The color 25 is housed in the cylinder chamber 201 and attached to the -X side end of the rod 21. The color 25 is formed by a flat plate portion 251 and a protruding portion 252. The flat plate portion 251 is a circular plate-shaped member centered on the axis L. The diameter of the flat plate portion 251 is smaller than the inner diameter of the cylinder tube 20 and larger than the outer shape of the rod 21. A bumper 253 made of, for example, a resin material is attached to the -X side surface of the flat plate portion 251. In the initial state, the flat plate portion 251 and the +X side surface of the head cover 26 are in contact with each other through the bumper 253.

[0028] The protruding portion 252 is a rod-shaped member centered on the axis L and is formed on the surface 251a on the +X side of the flat plate portion 251. That is, the protruding portion 252 protrudes from the surface 251a toward the +X side. The diameter of the protruding portion 252 is smaller than the diameter of the opening 210b of the first flow path 210 formed in the above-described rod 21. A male thread is formed on the protruding portion 252 and is screwed to the female thread formed in the opening 210b. Thereby, the collar 25 is attached to the rod 21.

[0029] In addition, as described above, the vent hole 213 is formed at a position on the +X side with respect to the end face on the +X side of the protruding portion 252 when the collar 25 is attached to the rod 21.

[0030] <Opening / closing portion 22> The opening / closing portion 22 is housed in the cylinder chamber 201 and has a cylindrical shape with a through hole 220 formed therein. The opening / closing portion 22 has an outer shape in which a flange portion 221 is formed on an outer peripheral wall surface whose outer diameter is smaller than the inner diameter of the cylinder tube 20. The outer diameter of the flange portion 221 is substantially equal to the inner diameter of the cylinder tube 20. A groove is formed along the outer periphery on the outer peripheral wall surface of the flange portion 221, and a seal member 222 such as a resin material is disposed in the groove. The cylinder chamber 201 is partitioned such that the -X side with respect to the flange portion 221 is the first air chamber 201a and the +X side with respect to the flange portion 221 is the second air chamber 201b. That is, the opening / closing portion 22 partitions the cylinder chamber 201 into the first air chamber 201a and the second air chamber 201b.

[0031] The through-hole 220 is formed along the X direction centered on the axis L and penetrates the opening / closing part 22. The second part 215 of the rod 21 is inserted into the through-hole 220. The opening / closing part 22 is capable of reciprocating along the X direction together with the rod 21 and is also capable of reciprocating along the X direction relative to the rod 21. In other words, the opening / closing part 22 is slidably arranged with respect to the rod 21. Specifically, since the rod 21 is inserted into the through-hole 220, the opening / closing part 22 is a piston slidably arranged on the outer peripheral wall surface 218 of the rod 21. As shown in FIG. 2, in the initial state, the end portion of the opening / closing part 22 on the X direction - side is in contact with the surface 251a of the flat part 251 of the collar 25.

[0032] The through-hole 220 is formed by a small-diameter part 220a and a large-diameter part 220b having different diameters. The small-diameter part 220a has a diameter substantially equal to the outer diameter of the rod 21 and is formed on the X direction + side of the position where the flange part 221 is formed. The large-diameter part 220b has a diameter larger than the outer diameter of the rod 21 and is formed on the X direction - side of the position where the flange part 221 is formed.

[0033] Grooves 220c and 220d are formed on the wall surface of the through-hole 220 (i.e., the inner peripheral wall surface of the opening / closing part 22), and seal members 223a and 223b such as resin materials are arranged. Specifically, the groove 220c is formed in the small-diameter part 220a, and the groove 220d is formed in the large-diameter part 220b. That is, the seal member 223a is arranged on the X direction + side of the flange part 221, and the seal member 223b is arranged on the X direction - side of the flange part 221.

[0034] <Holding part 23> The holding part 23 is accommodated in the cylinder chamber 201 and holds the biasing part 24 described later. The holding part 23 has a cylindrical shape in which a through-hole 230 is formed. A flange 231 is formed on the X direction + side of the holding part 23. The biasing part 24 described later is in contact with the surface on the X direction - side of this flange 231.

[0035] The through hole 230 is formed along the X direction with the axis L as the center and penetrates the holding portion 23. A rod 21 is inserted into the through hole 230. Specifically, the diameter of the through hole 230 is smaller than the outer diameter of the first portion 214 of the rod 21 and larger than the outer diameter of the second portion 215. That is, a part of the surface of the flange 231 of the holding portion 23 on the + side in the X direction is in contact with the stepped portion 216 of the rod 21. Therefore, the holding portion 23 is disposed on the outer peripheral wall surface 218 of the rod 21 and is disposed so as to be reciprocally movable along the X direction integrally with the rod 21. A bumper 232, such as a resin material, is attached to the remaining portion of the surface of the flange 231 on the + side in the X direction.

[0036] <Biasing portion 24> The biasing portion 24 is an elastic member such as a coil spring. The biasing portion 24 is disposed between the opening and closing portion 22 and the holding portion 23 outside the rod 21. Specifically, the end portion of the biasing portion 24 on the + side in the X direction is in contact with the surface of the flange 231 of the holding portion 23 on the - side in the X direction, and the end portion on the - side in the X direction is in contact with the surface of the flange portion 221 formed on the opening and closing portion 22 on the + side in the X direction.

[0037] Since the holding portion 23 is in contact with the stepped portion 216 of the rod 21 as described above, the holding portion 23 does not move relative to the rod 21. Therefore, the biasing portion 24 biases the opening and closing portion 22 in the - side direction in the X direction (i.e., the housing direction).

[0038] <Relay portion 3> The relay portion 3 is disposed at a position spaced apart from the cylinder portion 2 on the + side in the X direction. The relay portion 3 includes a main body portion 30, a mounting portion 31, the second supply port 6 described above, the second exhaust port 7, the second flow path 303, and a check valve 304. The mounting portion 31 is a flat plate-like member. A protruding holding portion 311 protruding in the - side direction in the X direction with the axis L as the center is formed on the mounting portion 31. The protruding holding portion 311 holds the check valve 304.

[0039] The main body 30 is fixed to the mounting portion 31 by a screw member 32. A groove is formed on the surface of the mounting portion 31 where it abuts against the main body 30, and a sealing member 310 made of, for example, a resin material is placed in this groove. When the main body 30 is attached to the mounting portion 31, the check valve 304 held by the protruding holding portion 311 is placed in the second flow path 303 formed in the main body 30.

[0040] The main body 30 is, for example, a rectangular block. As described above, the second supply port 6 has a sealing member 305 made of, for example, a resin material arranged along the inner peripheral wall surface of the second supply port 6. The sealing member 305 is arranged so that the end on the negative X-direction side protrudes slightly toward the negative X-direction side beyond the opposing wall surface 301. As described above, the second exhaust port 7 is an opening formed in the upper wall surface 302 on the positive Z-direction side of the main body 30. The second exhaust port 7 is connected to the external device 100 by a conduit. That is, the relay unit 3 is connected to the external device 100 via the second exhaust port 7.

[0041] The second flow path 303 connects the second supply port 6 and the second exhaust port 7 inside the main body 30. Compressed air supplied from the first flow path 210 formed in the rod 21 from the cylinder 2 is supplied from the second supply port 6 to the second flow path 303. The compressed air flowing through the second flow path 303 is exhausted from the second exhaust port 7 and supplied to the external device 100. The check valve 304 is disposed in the second flow path 303 while being held by the protruding holder 311 as described above, and prevents the compressed air from flowing back from the second exhaust port 7 toward the second supply port 6. Note that instead of the check valve 304, a solenoid valve that opens and closes the flow path by an electric signal, a motor-driven valve, or an air-operated valve that operates by air pressure may be used.

[0042] <Operation of compressed air supply device 1> In addition to FIGS. 1 and 2, the operation of the compressed air supply device 1 will be described with reference to FIGS. 3(A) and 3(B). FIG. 3(A) is a cross-sectional view of the compressed air supply device 1 in a transient state, and FIG. 3(B) is a cross-sectional view of the compressed air supply device 1 in an operating state. Note that FIGS. 3(A) and 3(B) show cross-sections of the compressed air supply device 1 in the same direction as FIG. 2. Further, the operating state means a state in which the compressed air supply device 1 can supply a fluid (actuating air) such as compressed air to the external device 100. The transient state is a state in which the compressed air supply device 1 in the initial state is in the process of transitioning to the operating state, and the compressed air supply device 1 has not started supplying actuating air to the external device 100.

[0043] The operation of the compressed air supply device 1 when compressed air (actuating air) is supplied to the first supply port 4 of the compressed air supply device 1 in the initial state shown in FIGS. 1 and 2 will be described. When actuating air is supplied to the first supply port 4, the pressure in the first air chamber 201a of the cylinder chamber 201 becomes higher than the pressure in the second air chamber 201b. That is, the differential pressure of the first air chamber 201a with respect to the second air chamber 201b increases.

[0044] When the differential pressure increases, the rod 21, the collar 25 attached to the rod 21, and the opening / closing part 22, the holding part 23, and the biasing part 24 into which the rod 21 is inserted start to move in the +X direction. That is, with the vent hole 213 of the rod 21 closed by the small-diameter part 220a of the opening / closing part 22, the collar 25, the opening / closing part 22, the holding part 23, and the biasing part 24 move in the +X direction together with the rod 21.

[0045] Due to the above movement, the first portion 214 of the rod 21 protrudes from the end portion 200b of the cylinder tube 20 in the +X direction (i.e., the protruding direction) more than that shown in FIG. 2. Then, the end portion 211 of the rod 21 abuts against the second supply port 6 provided on the opposing wall surface 301 of the relay portion 3. For this reason, the opposing wall surface 301 can be referred to as a contact wall surface that abuts against the end portion 211 of the rod 21 protruding in the protruding direction.

[0046] When the rod 21 abuts against the opposing wall surface 301, specifically, the end portion 211 abuts against the seal member 305 provided at the second supply port 6. At this time, the first flow path 210 formed inside the rod 21 communicates with the second flow path 303 via the first exhaust port 210a and the second supply port 6 formed in the relay portion 3. That is, the compressed air supply device 1 enters the transitional state shown in Fig. 3(A).

[0047] Immediately after the end portion 211 abuts against the opposing wall surface 301, the positional relationship among the rod 21, the collar 25, the opening / closing portion 22, the holding portion 23, and the biasing portion 24 is the same as in the initial state. That is, the vent hole 213 is closed by the opening / closing portion 22. At this time, since the end portion 211 of the rod 21 abuts against the second supply port 6, the rod 21 and the collar 25 do not move in the +X direction more than the state shown in Fig. 3(A). That is, the movement of the rod 21 in the protruding direction has stopped. Further, since a part of the surface of the flange 231 on the +X side of the holding portion 23 abuts against the stepped portion 216 of the rod 21, the holding portion 23 does not move in the +X direction more than the state shown in Fig. 3(A).

[0048] After the movement of the rod 21 stops, when operating air is further supplied from the first supply port 4 and the differential pressure of the first air chamber 201a with respect to the second air chamber 201b becomes equal to or greater than the threshold value, only the opening / closing portion 22 starts to move in the protruding direction against the biasing force of the biasing portion 24. That is, the opening / closing portion 22 moves in the protruding direction with respect to the rod 21. Note that the threshold value is, for example, 0.1 MPa. In other words, the biasing force of the biasing portion 24 is set such that the opening / closing portion 22 can move in the protruding direction when the differential pressure becomes 0.1 MPa or more.

[0049] When the opening / closing portion 22 moves relative to the rod 21, the positional relationship between the vent hole 213 and the opening / closing portion 22 changes. That is, due to the relative movement of the opening / closing portion 22, the small-diameter portion 220a of the through hole 220 formed in the opening / closing portion 22 is located on the +X side more than the position where the vent hole 213 is formed. As a result, the compressed air supply device 1 enters the operating state shown in Fig. 3(B).

[0050] As shown in FIG. 3(B), in the X direction, the position where the vent hole 213 is formed overlaps with the position of the large-diameter portion 220b of the through-hole 220 formed in the opening / closing portion 22. As described above, the diameter of the large-diameter portion 220b is larger than the outer diameter of the rod 21. Therefore, the state where the vent hole 213 is closed by the opening / closing portion 22 is released, and the vent hole 213 is opened. In other words, when the differential pressure of the second air chamber 201b with respect to the first air chamber 201a becomes equal to or greater than the threshold value, the opening / closing portion 22 opens the vent hole 213. Thereby, the first flow path 210 formed inside the rod 21 communicates with the first air chamber 201a of the cylinder chamber 201.

[0051] Thereby, the operating air supplied through the first supply port 4 is supplied to the first flow path 210 through the vent hole 213. Then, as described above, the first flow path 210 communicates with the second flow path 303 through the first exhaust port 210a and the second supply port 6. Therefore, the operating air flowing through the first flow path 210 is exhausted from the first exhaust port 210a and supplied to the second flow path 303 of the relay portion 3 through the second supply port 6. At this time, since the end portion 211 is in contact with the seal member 305, it is possible to suppress the operating air from leaking to the outside between the end portion 211 and the second supply port 6. Then, the operating air exhausted from the first exhaust port 210a flows through the second flow path 303 of the relay portion 3, is exhausted from the second exhaust port 7, and is supplied to the external device 100.

[0052] 3(B), when the supply of working air is stopped and the first air chamber 201a of the cylinder chamber 201 is evacuated, the opening / closing unit 22 moves relatively to the rod 21 toward the negative side in the X direction (the housing direction) due to the biasing force of the biasing unit 24. As a result, the vent hole 213 is closed by the small diameter portion 220a of the through hole 220. In other words, when the differential pressure of the second air chamber 201b relative to the first air chamber 201a becomes less than the threshold value, the opening / closing unit 22 closes the vent hole 213. That is, the opening / closing unit 22 opens or closes the vent hole 213 depending on the differential pressure of the second air chamber 201b relative to the first air chamber 201a. Furthermore, the rod 21 moves toward the negative side in the X direction (the housing direction) and is housed within the cylinder chamber 201. As the rod 21 moves in the storing direction, the collar 25, the opening / closing portion 22, the holding portion 23, and the biasing portion 24 also move in the storing direction, returning to the initial state shown in FIG.

[0053] According to the above-described embodiment, at least one of the following advantageous effects can be obtained.

[0054] (1) The compressed air supply device 1 includes a rod 21 and an opening / closing unit 22. The rod 21 is disposed in a cylinder chamber 201, and includes a first exhaust port 210a formed at an end 211, a vent port 213 communicating with a first air chamber 201a, and a first flow path 210 communicating between the first exhaust port 210a and the vent port 213 and through which compressed air flows. The opening / closing unit 22 is disposed in the cylinder chamber 201, and opens or closes the vent port 213 in response to a pressure difference between the first air chamber 201a and the second air chamber 201b. When the opening / closing unit 22 opens the vent port 213 in response to the pressure difference, the compressed air (working air) supplied to the first air chamber 201a flows through the first flow path 210, is exhausted from the first exhaust port 210a, and is supplied to the external device 100. As a result, the opening / closing section 22 operates in response to the pressure difference, making it possible to supply compressed air to the external device 100 while ensuring airtightness, compared to when the opening / closing section 22 opens or closes the ventilation opening 213 in response to contact with other components, etc.

[0055] Also, the opening / closing part 22 is operated using the compressed air supplied to the external device 100. For this reason, it is not necessary to separately provide piping and valves for supplying compressed air to the external device 100 and piping and valves for supplying compressed air for operating the compressed air supply device 1, which contributes to space saving and cost reduction.

[0056] (2) The opening / closing part 22 is arranged slidably with respect to the rod 21. The rod 21 reciprocates in a protruding direction protruding outside the cylinder chamber 201 and a housing direction housed in the cylinder chamber 201. The opening / closing part 22 is biased toward the housing direction by the biasing part 24. Thereby, when the opening / closing part 22 moves according to the differential pressure, it becomes possible to open or close the vent hole 213 formed in the rod 21.

[0057] (3) When the differential pressure of the first air chamber 201a with respect to the second air chamber 201b is less than the threshold value, the rod 21, the opening / closing part 22, and the biasing part 24 move in the protruding direction with the vent hole 213 closed by the opening / closing part 22. When the differential pressure becomes equal to or greater than the threshold value after the movement of the rod 21 in the protruding direction stops, the opening / closing part 22 moves in the protruding direction with respect to the rod 21 against the biasing force of the biasing part 24, thereby opening the vent hole 213.

[0058] As a result, when the movement of the rod 21 stops by contacting other devices or other members and a flow path through which compressed air flows is formed, and then the differential pressure of the first air chamber 201a with respect to the second air chamber 201b becomes equal to or greater than the threshold value, the compressed air is exhausted from the first exhaust port 210a. As a result, since the compressed air is exhausted after ensuring airtightness at the first exhaust port 210a, leakage of the compressed air from the first exhaust port 210a is suppressed.

[0059] Also, the rod 21 and the opening / closing part 22 are operated using the compressed air supplied to the external device 100. For this reason, it is not necessary to separately provide piping and valves for supplying compressed air to the external device 100 and piping and valves for supplying compressed air for operating the compressed air supply device 1, which contributes to space saving and cost reduction.

[0060] (4) The opening / closing part 22 is slidably arranged on the outer peripheral wall surface 218 of the rod 21, and partitions the cylinder chamber 201 into a first air chamber 201a and a second air chamber 201b. The ventilation port 213 is formed on the outer peripheral wall surface 218. Thereby, when the differential pressure is equal to or greater than the threshold value, the opening / closing part 22 can move relative to the rod 21 and can open the ventilation port 213.

[0061] (5) The compressed air supply device 1 is arranged on the outer peripheral wall surface 218 of the rod 21 and includes a holding part 23 that holds the biasing part 24. The holding part 23 moves together with the rod 21. Thereby, even when the rod 21 moves in the protruding direction, the state in which the ventilation port 213 is blocked can be maintained by the biasing force of the biasing part 24. As a result, it is suppressed that the compressed air is exhausted from the first exhaust port 210a in a state where no flow path is formed between the first flow path 210 of the rod 21 and other devices or other members.

[0062] (6) The compressed air supply device 1 includes a relay part 3 connected to the external device 100. The relay part 3 has a second flow path 303 that communicates a facing wall surface 301, which is a contact wall surface that contacts the end part 211 of the rod 21 protruding in the protruding direction, a second supply port 6 provided on the facing wall surface 301, and a second exhaust port 7 formed on the upper wall surface 302. When the rod 21 protrudes in the protruding direction and the end part 211 contacts the facing wall surface 301, the second flow path 303 communicates with the first flow path 210. The compressed air exhausted from the first exhaust port 210a is supplied to the second flow path 303 through the second supply port 6, exhausted from the second exhaust port 7, and supplied to the external device 100. Thereby, after the rod 21 and the facing wall surface 301 contact each other and the first flow path 210 and the second flow path 303 communicate in an airtight state, it becomes possible to exhaust the compressed air from the first exhaust port 210a. As a result, it is suppressed that the compressed air leaks out from the boundary surface between the first exhaust port 210a and the second supply port 6.

[0063] (7) A seal member 305 is provided at the second supply port 6. This enhances the airtightness at the interface between the first exhaust port 210a and the second supply port 6, and can suppress the leakage of compressed air.

[0064] (8) A check valve 304 is arranged in the second flow path 303. This suppresses the compressed air flowing backward from the external device 100 from flowing into the compressed air supply device 1 through the first exhaust port 210a.

[0065] <First Modification Example> FIG. 4(A) is a cross-sectional view of the compressed air supply device 1 in the transient state in the first modification example, and FIG. 4(B) is a cross-sectional view of the compressed air supply device 1 in the operating state in the first modification example. Note that FIGS. 4(A) and 4(B) show the cross-section of the compressed air supply device 1 in the same direction as FIG. 2.

[0066] In the first modification example, for components having the same or substantially the same configuration as those in the embodiment, the same reference numerals as those used in the embodiment are employed. Hereinafter, the differences from the embodiment will be described. For points not particularly described, they are the same as in the embodiment.

[0067] In the compressed air supply device 1 of the first modification example, the seal member 305 is not arranged at the second supply port 6 of the relay portion 3, and the seal member 217 is arranged at the first exhaust port 210a of the rod 21. The end portion of the seal member 217 on the + side in the X direction protrudes slightly more in the + side in the X direction than the end portion 211 of the rod 21.

[0068] Therefore, in the transient state shown in FIG. 4(A) and the operating state shown in FIG. 4(B), the seal member 217 and the opposing wall surface 301 of the relay portion 3 are in contact with each other. Thereby, while suppressing the working air from leaking to the outside between the end portion 211 and the second supply port 6, the first flow path 210 and the second flow path 303 can be communicated with each other through the first exhaust port 210a and the second supply port 6. The operation of the compressed air supply device 1 of the first modification example is the same as in the embodiment.

[0069] In the first modification example, at least one of the same operational effects as those of (1) to (6) and (8) obtained according to the embodiment and the following operational effects is obtained.

[0070] (9) A seal member 217 is provided at the first exhaust port 210a of the rod 21. Thereby, the airtightness at the interface between the first exhaust port 210a and the second supply port 6 can be enhanced, and leakage of compressed air can be suppressed.

[0071] <Second Modification Example> FIG. 5(A), FIG. 5(B), and FIG. 6(A) are cross-sectional views of the compressed air supply device 1 in the second modification example. FIG. 5(A) is a cross-sectional view when the compressed air supply device 1 of the second modification example is in the initial state, FIG. 5(B) is a cross-sectional view when the compressed air supply device 1 in the second modification example is in the transient state, and FIG. 6(A) is a cross-sectional view when the compressed air supply device 1 in the second modification example is in the operating state. Note that FIG. 5(A), FIG. 5(B), and FIG. 6(A) show cross-sections of the compressed air supply device 1 in the same direction as FIG. 2.

[0072] In the second modification example, for components that are the same as or substantially the same as those in the embodiment, the same reference numerals as those used in the embodiment are employed. Hereinafter, differences from the embodiment will be described. For points not particularly described, they are the same as in the case of the embodiment.

[0073] The compressed air supply device 1 of the second modification example differs from the compressed air supply device 1 of the embodiment in that the relay portion 3 does not have a check valve 304 and a mounting portion 31 that holds the check valve 304. Other configurations are the same as those of the compressed air supply device 1 of the embodiment. Therefore, the compressed air supply device 1 of the second modification example is suitable for use in a vacuum environment.

[0074] In the compressed air supply device 1 of the second modification, the rod 21 and the opening / closing unit 22 operate in the same manner as in the embodiment due to the working air supplied from the first supply port 4. As a result, the working air that has flowed through the first flow path 210 of the rod 21 is supplied to the pneumatic equipment via the relay unit 3. That is, even in the compressed air supply device 1 that is not provided with the check valve 304 and is used in a vacuum environment, it is possible to obtain at least one of the effects (1) to (7) obtained by the embodiment.

[0075] In the second modified example, similarly to the first modified example, the seal member 305 may not be disposed at the second supply port 6 of the relay section 3. FIG. 6(B) is a cross-sectional view of the compressed air supply device 1 in this case when it is in operation. FIG. 6(B) shows a cross-section of the compressed air supply device 1 in the same direction as FIG. 2. In this case, the same reference numerals as those used in the embodiment will be used for configurations that are similar or substantially similar to those in the embodiment, the first modified example, and the second modified example. Below, differences from the embodiment will be explained. Points that are not particularly explained are the same as in the embodiment.

[0076] 6(B), a seal member 217 is disposed at the first exhaust port 210a of the rod 21. The end of the seal member 217 on the positive X-direction side protrudes slightly further in the positive X-direction than the end 211 of the rod 21.

[0077] 6(B), the seal member 217 comes into contact with the opposing wall surface 301 of the relay section 3. As a result, similar to the first modified example, the first flow path 210 and the second flow path 303 can be communicated with each other while preventing the working air from leaking to the outside from between the end portion 211 and the second supply port 6. That is, even in the compressed air supply device 1 that is not provided with the check valve 304 and is used in a vacuum environment, at least one of the effects obtained by the first modified example can be obtained.

[0078] <Third Modification> 7(A) and 7(B) are cross-sectional views of a compressed air supplying device 1 in a third modified example. FIG. 7(A) is a cross-sectional view of the compressed air supplying device 1 in the third modified example when it is in an initial state, and FIG. 7(B) is a cross-sectional view of the compressed air supplying device 1 in the third modified example when it is in an operating state. Note that FIGS. 7(A) and 7(B) show cross sections of the compressed air supplying device 1 in the same direction as FIG. 2. Also, although FIGS. 7(A) and 7(B) only show cross sections of the cylinder portion 2, the compressed air supplying device 1 in the third modified example also has a relay portion 3 similar to that of the embodiment.

[0079] In the third modified example, the same reference numerals as those in the embodiment are used for the same or substantially similar configurations as those in the embodiment. The following describes the differences from the embodiment. The points that are not particularly described are the same as those in the embodiment.

[0080] The cylinder portion 2 of the third modified example has a rod 91 and an opening / closing portion 92 that are different from the rod 21 and the opening / closing portion 22 of the embodiment. In addition, the cylinder portion 2 of the third modified example does not have the holding portion 23 and the collar 25 of the embodiment.

[0081] <Rod 91> Like the rod 21 of the embodiment, the rod 91 is a hollow member that extends along the X direction and has a first flow path 210 formed therein. The rod 91 is housed in the cylinder chamber 201 so as to be able to move back and forth along the X direction. The rod 91 is formed by a third portion 912 and a fourth portion 913 that have different outer diameters. The third portion 912 is the portion of the rod 91 on the positive side in the X direction, and its outer diameter is approximately equal to the diameter of the insertion hole 202.

[0082] The fourth part 913 is formed on the X-direction side with respect to the third part 912. The outer diameter of the fourth part 913 is larger than the outer diameter of the third part 912 and smaller than the inner diameter of the cylinder tube 20. A flange portion 914 is formed on the outer peripheral wall surface (i.e., the outer peripheral wall surface of the rod 91) 919 of the fourth part 913. The outer diameter of the flange portion 914 is substantially equal to the inner diameter of the cylinder tube 20. A groove is formed along the outer periphery on the outer peripheral wall surface of the flange portion 914, and a seal member 915 such as a resin material is disposed in the groove. The flange portion 914, which is a part of the outer peripheral wall surface 919 of the fourth part 913, partitions the cylinder chamber 201 into a first air chamber 201a and a second air chamber 201b.

[0083] A storage portion 917, which is a space for housing an opening / closing portion 92 and a biasing portion 24 described later, is formed in the fourth part 913. The storage portion 917 is formed at a position offset in a direction intersecting the X direction with respect to the axis L. In FIGS. 7(A) and 7(B), a case where the storage portion 917 is formed on the +Z direction side with respect to the axis L is shown.

[0084] As shown in FIG. 7(B), the storage portion 917 communicates with the first air chamber 201a through an opening formed in the end surface 917a on the X-direction side of the fourth part 913. The length of the storage portion 917 along the X direction is shorter than the length of the fourth part 913 along the X direction. Therefore, a bottom surface 917b is formed on the +X direction side of the storage portion 917.

[0085] A ring-shaped braking member 918 having a through hole formed therein is disposed near the end on the X-direction side of the inner peripheral wall surface 917c of the storage portion 917. The diameter of the through hole of the braking member 918 is smaller than the inner diameter of the storage portion 917. For this reason, when the opening / closing portion 92 described later is housed in the storage portion 917, the opening / closing portion 92 is prevented from falling off to the outside from the X-direction side of the storage portion 917, and the inside of the storage portion 917 and the first air chamber 201a communicate with each other through the through hole. Further, the vent hole 213 is formed on the +X direction side of the inner peripheral wall surface 917c with respect to the braking member 918.

[0086] <Opening / Closing Portion 92> The opening / closing part 92 is a columnar member extending along the X direction and is stored in the above-described storage part 917. The length of the opening / closing part 92 along the X direction is shorter than the length of the storage part 917 along the X direction. Also, the diameter of the opening / closing part 92 is substantially equal to the inner diameter of the storage part 917. Grooves are formed along the outer peripheral wall surface of the opening / closing part 92, and seal members 921 and 922 such as a resin material are arranged in the grooves. For this reason, the opening / closing part 92 is arranged to be slidable along the X direction with respect to the rod 91.

[0087] An urging part 24 is arranged between the surface 92a on the +X side of the opening / closing part 92 and the bottom surface 917b of the storage part 917. Specifically, the end on the +X side of the urging part 24 abuts against the bottom surface 917b, and the end on the -X side abuts against the surface 92a of the opening / closing part 92. Thereby, the opening / closing part 92 is urged in the -X direction, that is, the accommodating direction, by the urging part 24.

[0088] Since the opening / closing part 92 is urged in the accommodating direction, in the initial state shown in Fig. 7(A), the surface 92b on the -X side of the opening / closing part 92 abuts against the braking member 918. As shown in Fig. 7(A), when the opening / closing part 92 abuts against the braking member 918, the outer peripheral wall surface of the opening / closing part 92 overlaps with the air vent 213. That is, the air vent 213 is closed by the opening / closing part 92. In other words, the position where the air vent 213 is formed and the length of the opening / closing part 92 in the X direction are determined such that the outer peripheral wall surface of the opening / closing part 92 can overlap with the air vent 213 when the opening / closing part 92 abuts against the braking member 918.

[0089] <Operation of the Compressed Air Supply Device 1> 7(A), the end surface 917a of the rod 91 on the negative side in the X direction abuts against the head cover 26. In this state, when working air is supplied to the first supply port 4 and the differential pressure between the first air chamber 201a and the second air chamber 201b increases, the rod 91 starts to move toward the positive side in the X direction. At this time, the opening / closing unit 92 stored in the storage unit 917 also moves toward the positive side in the X direction together with the rod 91. In other words, with the vent port 213 closed by the opening / closing unit 92, the opening / closing unit 92 and the biasing unit 24 move toward the positive side in the X direction together with the rod 91.

[0090] The movement described above causes the third portion 912 of the rod 91 to protrude from the end 200b of the cylinder tube 20 toward the positive side in the X direction. Then, the end 911 on the positive side in the X direction of the rod 91 abuts against the second supply port 6 provided in the opposing wall surface 301 of the relay unit 3, and the movement of the rod 91 stops, entering a transient state (see FIG. 3(A)). Immediately after the rod 91 abuts against the opposing wall surface 301, the opening / closing unit 92 closes the vent port 213, as in the initial state.

[0091] After the movement of the rod 91 stops, working air is further supplied from the first supply port 4, and when the differential pressure between the first air chamber 201a and the second air chamber 201b becomes equal to or greater than the threshold, only the opening / closing unit 92 starts to move in the protruding direction against the biasing force of the biasing unit 24. That is, the opening / closing unit 92 moves in the protruding direction relative to the rod 91. As the opening / closing unit 92 moves relative to the rod 91, the positional relationship between the vent hole 213 and the opening / closing unit 92 changes. That is, as a result of the relative movement of the opening / closing unit 92, the opening / closing unit 92 is positioned on the positive side in the X direction relative to the position where the vent hole 213 was formed. As a result, the vent hole 213 is opened by the opening / closing unit 92, and the compressed air supply device 1 enters the operating state shown in FIG. 7(B).

[0092] As a result, the vent port 213 communicates with the first air chamber 201a via the through holes of the storage portion 917 and the braking member 918. This allows the operating air supplied via the first supply port 4 to be supplied to the first flow path 210 via the vent port 213. The operating air supplied to the first flow path 210 is supplied to the external device 100 in the same manner as in the embodiment.

[0093] In the third modified example, at least one of the following effects and advantages can be obtained in addition to the same effects (1) to (3) and (6) to (8) as those obtained in the embodiment.

[0094] (10) The rod 91 has a storage section 917 that stores therein the opening / closing section 92 and the biasing section 24. The vent hole 213 is provided on an inner peripheral wall surface 917c of the storage section 917, and a flange section 914 that is part of an outer peripheral wall surface 919 of the rod 91 divides the cylinder chamber 201 into a first air chamber 201a and a second air chamber 201b. This makes it possible to arrange the opening / closing section 92 inside the rod 91, contributing to the radial miniaturization of the cylinder section 2.

[0095] The cylinder unit 2 having the above-described configuration is not limited to being applied to the embodiment, but may be applied to the first or second modified example. Furthermore, the opening / closing unit 92 of the third modified example may be provided within the opening / closing unit 22 of the embodiment, the first or second modified example. In this case, the opening / closing unit 22 is fixed to the rod 21 so as not to be able to move relative to the rod 21. A storage section similar to the storage section 917 of the third modified example may be formed in the opening / closing unit 22, and the opening / closing unit 92 and the biasing unit 24 of the second modified example may be stored within this storage section.

[0096] Although various embodiments and modifications have been described above, the present invention is not limited to these. Other embodiments that are conceivable within the scope of the technical idea of the present invention are also included within the scope of the present invention.

[0097] The compressed air supply device 1 may not include the relay unit 3. In this case, the end 211 of the rod 21 or the end 911 of the rod 91 may directly abut against the external device 100, and a supply port for operating air provided in the external device 100 may communicate with the first flow path 210 via the first exhaust port 210a. [Explanation of symbols]

[0098] 1 compressed air supply device, 2 cylinder portion, 3 relay portion, 4 first supply port, 6 second supply port, 7 second exhaust port, 20 cylinder tube, 21, 91 rod, 22, 92 opening / closing portion, 23 holding portion, 24 biasing portion, 100 external device, 201 cylinder chamber, 201a first air chamber, 201b second air chamber, 210 first flow path, 210a first exhaust port, 213 vent port, 217, 305 sealing member, 218, 919 outer peripheral wall surface, 303 second flow path, 304 check valve, 914 flange portion, 917c inner peripheral wall surface

Claims

1. A compressed air supply device that supplies compressed air to an external device operated by compressed air, comprising: a cylinder chamber partitioned into a first air chamber to which compressed air is supplied through a first supply port and a second air chamber; a rod disposed in the cylinder chamber, having a first exhaust port formed at an end, a vent port communicating with the first air chamber, and a first flow path communicating the first exhaust port and the vent port through which compressed air flows; an opening / closing part disposed in the cylinder chamber that opens or closes the vent port according to a differential pressure of the first air chamber with respect to the second air chamber; When the opening / closing part opens the vent port according to the differential pressure, the compressed air supplied to the first air chamber flows through the first flow path, is exhausted from the first exhaust port, and is supplied to the external device. The compressed air supply device.

2. In the compressed air supply device according to Claim 1, the opening / closing part is slidably disposed with respect to the rod, The compressed air supply device includes a biasing part that biases the opening / closing part.

3. In the compressed air supply device according to Claim 2, the rod reciprocates in a protruding direction protruding outside the cylinder chamber and a housing direction housed in the cylinder chamber, The biasing part biases the opening / closing part in the housing direction. The compressed air supply device.

4. In the compressed air supply device according to Claim 3, When the differential pressure is less than the threshold value, the rod, the opening / closing part, and the biasing part move in the protruding direction with the vent port closed by the opening / closing part, When the differential pressure becomes equal to or greater than the threshold value after the movement of the rod in the protruding direction stops, the opening / closing part moves in the protruding direction with respect to the rod against the biasing force of the biasing part, thereby opening the vent port. Compressed air supply device.

5. In the compressed air supply device according to Claim 4, the opening / closing part is slidably disposed on the outer peripheral wall surface of the rod, partitioning the cylinder chamber into the first air chamber and the second air chamber, The vent port is formed on the outer peripheral wall surface. The compressed air supply device.

6. In the compressed air supply device according to Claim 5, a holding part disposed on the outer peripheral wall surface of the rod for holding the biasing part, The holding part moves together with the rod. The compressed air supply device.

7. In the compressed air supply device according to Claim 4, the rod has a storage part inside for storing the opening / closing part and the biasing part, The ventilation port is provided on the inner peripheral wall surface of the storage part, A compressed air supply device in which a part of the outer peripheral wall surface of the rod divides the cylinder chamber into the first air chamber and the second air chamber.

8. In the compressed air supply device according to claim 4, It is provided with a relay part connected to the external device, The relay part, A contact wall surface that contacts the end part of the rod protruding in the protruding direction, It has a second flow path that communicates a second supply port provided on the contact wall surface and a second exhaust port formed on a wall surface different from the contact wall surface, When the rod protrudes in the protruding direction and the end part contacts the contact wall surface, the second flow path communicates with the first flow path via the first exhaust port and the second supply port, The compressed air exhausted from the first exhaust port is supplied to the second flow path through the second supply port, exhausted from the second exhaust port, and supplied to the external device. A compressed air supply device.

9. In the compressed air supply device according to claim 8, A compressed air supply device in which a seal member is provided at the second supply port.

10. In the compressed air supply device according to claim 8, A compressed air supply device in which a seal member is provided at the first exhaust port of the rod.

11. In the compressed air supply device according to claim 8, A compressed air supply device in which a check valve is arranged in the second flow path.

12. In the compressed air supply device according to any one of claims 4 to 11, A compressed air supply device in which the threshold value of the differential pressure of the first air chamber with respect to the second air chamber is 0.1 MPa.

Images