WE CLAIM:
Claim 1. A pressure booster (10), comprising:
a first chamber (34);
5 a second chamber (36) adjacent to the first chamber
(34);
a piston rod (42) extending to the first chamber (34) and the second chamber (36);
a first piston (44) which, by being connected to one
10 end of the piston rod (42) inside the first chamber (34), is
configured to partition the first chamber (34) into a first
pressure boosting chamber (34a) on a side of the second
chamber (36), and a first drive chamber (34b) remote from
the second chamber (36);
15 a second piston (46) which, by being connected to
another end of the piston rod (42) inside the second chamber (36), is configured to partition the second chamber (36) into a second pressure boosting chamber (36a) on a side of the first chamber (34), and a second drive chamber (36b) 20 remote from the first chamber (34);
a position detecting sensor (70a, 70b) configured to detect a position of the first piston (44) or the second piston (46); and
a fluid supplying mechanism (48) configured to supply 25 fluid to at least one of the first pressure boosting chamber (34a) and the second pressure boosting chamber (36a), together with executing, based on a detection result of the position detecting sensor (70a, 70b), switching between an operation of supplying the fluid to the first drive chamber 30 (34b) and discharging the fluid from the second drive
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chamber (36b), and an operation of discharging the fluid from the first drive chamber (34b) and supplying the fluid to the second drive chamber (36b).
5 Claim 2. The pressure booster (10) according to claim
1, wherein the fluid supplying mechanism (48) comprises:
a first supply flow passage (50b) configured to supply
the fluid supplied from exterior into the first pressure
boosting chamber (34a);
10 a second supply flow passage (50c) configured to supply
the fluid supplied from the exterior into the second pressure boosting chamber (36a);
a first solenoid valve (22) configured to supply the fluid supplied from the exterior into the first drive 15 chamber (34b), or to discharge the fluid inside the first drive chamber (34b) to the exterior, based on a detection result of the position detecting sensor (70a, 70b); and
a second solenoid valve (24) configured to supply the fluid supplied from the exterior into the second drive 20 chamber (36b), or to discharge the fluid inside the second drive chamber (36b) to the exterior, based on the detection result of the position detecting sensor (70a, 70b).
Claim 3. The pressure booster (10) according to claim 25 2, wherein the fluid supplying mechanism (48) further comprises:
a first inlet check valve (52a) provided in the first supply flow passage (50b) and configured to prevent back-flowing of the fluid from the first pressure boosting 30 chamber (34a); and
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a second inlet check valve (52b) provided in the second supply flow passage (50c) and configured to prevent back-flowing of the fluid from the second pressure boosting chamber (36a). 5
Claim 4. The pressure booster (10) according to claim 1, further comprising:
a fluid output mechanism (56) configured to output to an exterior the fluid which was boosted in pressure in the 10 first pressure boosting chamber (34a) or the second pressure boosting chamber (36a);
wherein the fluid output mechanism (56) is configured to include a first outlet check valve (60a) configured to prevent back-flowing of the fluid into the first pressure 15 boosting chamber (34a), and a second outlet check valve
(60b) configured to prevent back-flowing of the fluid into the second pressure boosting chamber (36a).
Claim 5. The pressure booster (10) according to claim 20 1, wherein the position detecting sensor (70a, 70b)
comprises a first position detecting sensor (70a) configured to detect arrival of the first piston (44) or the second piston (46) at one end side of the first chamber (34) or the second chamber (36), and a second position detecting sensor 25 (70b) configured to detect arrival of the first piston (44) or the second piston (46) at another end side of the first chamber (34) or the second chamber (36).
Claim 6. The pressure booster (10) according to claim 30 1, wherein the position detecting sensor (70a, 70b)
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comprises a magnetic sensor configured to detect the position of the first piston (44) or the second piston (46) by detecting magnetism produced by a magnet (72) attached to the first piston (44) or the second piston (46). 5
Claim 7. The pressure booster (10) according to claim 1, wherein:
a center body (12) is interposed between the first
chamber (34) and the second chamber (36);
10 a first cover member (38) is disposed at an end of the
first drive chamber (34b) remote from the center body (12);
a second cover member (40) is disposed at an end of the second drive chamber (36b) remote from the center body (12);
the first piston (44) is displaced inside the first 15 chamber (34) without coming into contact with the center body (12) and the first cover member (38); and
the second piston (46) is displaced inside the second chamber (36) without coming into contact with the center body (12) and the second cover member (40).
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