JP2005214327A - Brake device of hydraulic motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely lock a hydraulic motor during the non-operation of the hydraulic motor even if an oil pressure chamber opening oil passage of a brake mechanism is clogged up with dust. <P>SOLUTION: This brake device of the hydraulic motor has two oil pressure opening oil passages for opening a locking release oil pressure chamber 11d to an oil tank 6 in the state where lock releasing oil pressure is not supplied, that is, a first opening oil passage via throttle (a drain oil passage 61) connected from the locking release oil pressure chamber 11d through a first throttle 13 to the oil tank 6 and an opening oil passage via oil pressure pilot switching valve formed by connecting a locking releasing oil pressure supply oil passage 55 to an oil tank 6 through an oil pressure pilot switching valve 8 when a spool of a manual switching valve 7 is located in a motor rotation stop position (a neutral position 7a) for stopping the rotation of a hydraulic motor 4. The opening oil passage via oil pressure pilot switching valve is formed of the locking release oil pressure supply oil passage 55 → the oil pressure pilot switching valve 8 → the oil passage 51 → the oil passage 43 → the manual switching valve 7 → the oil passage 42. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a brake device for a hydraulic motor used for driving a hydraulic winch or the like.

  The hydraulic winch has a configuration in which a suspended object hooked on a hook or the like provided at the tip of the rope can be moved up and down by rotating the winch drum by a hydraulic motor and winding and feeding the rope. Yes. The hydraulic motor rotates in response to the hydraulic pressure supplied from the hydraulic pump. A control valve is provided in the oil passage, and the hydraulic pressure supplied to the hydraulic motor is intermittently operated by operating the spool of the control valve. And by switching the direction, the winch drum can be operated and stopped, and the direction of rotation can be switched.

Further, since such a hydraulic winch is a machine for suspending heavy objects, a brake device is provided that securely locks (fixes) the rotating shaft of the hydraulic motor when the hydraulic winch is not in operation (non-rotating). This brake device is generally configured as a negative brake using a single-acting hydraulic cylinder, and when the hydraulic motor is not operating, the rotating shaft of the hydraulic motor is adjusted by the urging force of a spring provided in the single-acting hydraulic cylinder. Lock and release the lock by supplying hydraulic pressure (unlock hydraulic pressure) into the unlock hydraulic chamber of the single acting hydraulic cylinder and moving the piston in the direction opposite to the biasing force of the spring when the hydraulic motor rotates. To do. In addition, various safety devices related to the brake mechanism of the hydraulic motor have been devised in order to prevent a situation in which the winch drum idles and the suspended object falls when the hydraulic winch is switched from the stopped state to the activated state. (See the following patent document).
JP 2001-165111 A JP 2000-351585 A

  However, when the brake device of the hydraulic motor is configured as a negative brake as described above, there is a possibility that the hydraulic motor cannot be locked if there is residual pressure in the unlocking hydraulic chamber. For this reason, the brake device is provided with a hydraulic chamber opening oil passage that opens the unlocking hydraulic chamber to the oil tank when the unlocking hydraulic pressure is not supplied. However, the hydraulic chamber opening oil passage is clogged with debris or gold dust. In the closed state, residual pressure is generated in the unlocked hydraulic chamber and it becomes impossible to lock. To prevent such a situation from occurring and ensure high safety, garbage etc. As a result, it is necessary to spend a lot of time on the maintenance work to reliably remove the material, which is disadvantageous in terms of cost.

  The present invention has been made in view of such problems, and even when a clogging or the like occurs in the hydraulic chamber opening oil passage of the brake mechanism, the rotation of the hydraulic motor is reliably performed when the hydraulic motor is not operating. It is an object of the present invention to provide a brake device for a hydraulic motor that can lock a shaft and has a high safety and does not require much time for maintenance.

  The brake device for a hydraulic motor according to the present invention includes a hydraulic motor, and a first valve (for example, a manual switching valve 7 in the embodiment) that controls the rotation operation of the hydraulic motor by supplying and stopping the hydraulic pressure to the hydraulic motor. A brake mechanism (for example, the brake cylinder 11 in the embodiment) that locks the rotating shaft of the hydraulic motor when the hydraulic motor is not operated, and releases the lock when the unlock hydraulic pressure is supplied into the unlock hydraulic chamber; And a second valve for supplying the unlocking hydraulic pressure into the unlocking hydraulic supply oil passage when the hydraulic motor is rotated (for example, the hydraulic pilot switching valve 8 in the embodiment). In a brake device for a hydraulic motor configured with a lock release in the unlock hydraulic chamber of the brake mechanism Hydraulic chamber open fluid passage for releasing the lock releasing oil pressure chamber to the oil tank in a state where pressure is not supplied is provided at least two.

  In the brake device of the hydraulic motor having such a configuration, the hydraulic chamber opening oil passage is connected to the oil tank via the first throttle from the unlocking hydraulic chamber of the brake mechanism via the first throttle, When the spool of one valve is positioned at the motor rotation stop position for stopping the rotation of the hydraulic motor, the oil released via the second valve is formed by connecting the unlocking hydraulic supply oil passage to the oil tank via the second valve. It is preferable to have a passage (for example, an open oil passage via a hydraulic pilot switching valve in the embodiment). Alternatively, when the hydraulic chamber opening oil passage is located at a motor rotation stop position where the spool of the first valve stops the rotation of the hydraulic motor, the unlocking hydraulic supply oil passage is connected to the oil tank via the second valve. Branching from the downstream side of the second valve in the unlocked hydraulic pressure supply oil passage (for example, the hydraulic fluid via the hydraulic pilot switching valve in the embodiment) and the second valve via the second valve, It is preferable to have an open oil passage via a second throttle connected to the oil tank via the second throttle. Alternatively, the hydraulic chamber opening oil passage is connected to the oil tank via the first throttle from the unlocking hydraulic chamber of the brake mechanism via the first throttle, and downstream of the second valve in the unlocking hydraulic supply oil passage. It is preferable to have an open oil passage that is branched from the side and connected to the oil tank via the second throttle.

  In the brake device of the hydraulic motor having the above-described configuration, at least two hydraulic chamber opening oil passages that open the unlocking hydraulic chamber to the oil tank in a state where the unlocking hydraulic pressure is not supplied to the unlocking hydraulic chamber of the brake mechanism are provided. Therefore, even if one of the hydraulic chamber open oil passages is blocked due to clogging, etc., the remaining pressure in the unlocked hydraulic chamber is removed in the other hydraulic chamber open oil passage, and the hydraulic motor becomes unable to lock. There is nothing. In addition, even if one hydraulic chamber open oil passage becomes clogged in this way, it can be securely locked when the hydraulic motor is not in operation, so the safety for work is improved and much time is spent for maintenance. No need to apply

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a hydraulic motor control device having a hydraulic motor brake device according to a first embodiment of the present invention. The hydraulic motor can be used as a driving unit for various rotating machines. Here, an example in which the hydraulic motor is used as a driving unit for a hydraulic winch provided in a work platform or the like of an aerial work platform is shown.

  The hydraulic winch 1 includes a winch drum 2 rotatably supported on a frame (not shown), a rope 3 wound around the winch drum 2, and a suspension fitting (for example, a hook, not shown) attached to the tip of the rope 3. ). The winch drum 2 is attached to the rotating shaft 4a of the hydraulic motor 4, so that the winch drum 2 can be rotated by the rotating operation of the hydraulic motor 4 (rotating shaft 4a), and the rope 3 can be taken up and delivered. It has become.

  The control device for the hydraulic motor 4 includes a hydraulic pump 5 driven by a power source (not shown) (an internal combustion engine or an electric motor), an oil tank 6, a manual switching valve 7, a hydraulic pilot switching valve 8, and a brake cylinder including a single-acting hydraulic cylinder. (Brake mechanism) 11 and an oil passage for connecting them and the like. Here, the brake cylinder 11 is provided in a cylinder tube 11a, a piston rod 11b movably provided in the cylinder tube 11a, and contracted in a bottom region of the piston rod 11b in the cylinder tube 11a so that the piston rod 11b is always extended. The spring 11c is biased toward the braking side of the hydraulic motor 4. An unlock hydraulic chamber 11d is formed in the rod side region in the cylinder tube 11a.

  The manual switching valve 7 is a four-port, three-position valve. By operating a lever 7L to move a spool (not shown) and switching its position, the hydraulic motor 4 is supplied and stopped to rotate. It is possible to perform operation control (details will be described later). The P port of the manual switching valve 7 is connected to the discharge port of the hydraulic pump 5 through the oil passage 41, the T port is connected to the oil tank 6 through the oil passage 42, and the A port is hydraulically supplied through the oil passages 43, 44, 45. The port B is connected to the port on one side of the motor 4 and the port on the other side of the hydraulic motor 4 through oil passages 46, 47 and 48. This manual switching valve 7 is a so-called ABT connection type valve that connects the A port, B port and T port to each other when the spool is in the neutral position 7a, and is located at the left position 7b in FIG. In this case, the P port is connected to the A port and the T port is connected to the B port. When the port is located at the right position 7c in FIG. 1, the P port is connected to the B port and the T port is connected to the A port. Further, a check valve CV 1 that allows only a flow from the hydraulic pump 5 side to the hydraulic motor 4 side is interposed between the oil passage 44 and the oil passage 45, and between the oil passage 47 and the oil passage 48. In the same manner, a check valve CV2 that allows only the flow from the hydraulic pump 5 side to the hydraulic motor 4 side is interposed.

  The hydraulic pilot switching valve 8 is a 5-port 3-position type valve. The first port P1 is connected to the oil passage 43 via the oil passage 51 (that is, to the A port of the manual switching valve 7), and the second port P2 is the oil passage. 52 are connected to the oil passage 46 through 52 (that is, to the B port of the manual switching valve 7). The third port P3 is connected to the oil passage 45 via the oil passage 53 (but downstream of the check valve CV1), and the fourth port P4 is connected to the oil passage 48 via the oil passage 54 (but downstream of the check valve CV2). The fifth port P5 is connected to the unlocking hydraulic chamber 11d of the brake cylinder 11 via the unlocking hydraulic pressure supply oil passage 55, respectively. A filter 9 and a reducing valve 10 are interposed in the unlocking hydraulic pressure oil supply passage 55. When the spool is in the neutral position 8a, the hydraulic pilot switching valve 8 connects the first port P1 and the fifth port P5 to each other and blocks the remaining three ports P2, P3, P4, respectively. Is located at the left position 8b in FIG. 1, the first port P1 and the fifth port P5 are connected, the second port P2 and the fourth port P4 are connected, and the third port P3 is blocked. When the spool is positioned at the right position 8c in FIG. 1, the first port P1 and the third port P3 are connected, the second port P2 and the fifth port P5 are connected, and the fourth port P4 is blocked. .

  When the pressure in the oil passage 44 and the pressure in the oil passage 47 are the same, the hydraulic pilot switching valve 8 has a pilot pressure in the pilot oil passages 44a and 44b extending from the oil passage 44 and the oil passage 47, respectively. When the pressure in the oil passage 44 is higher than the pressure in the oil passage 47, the spool is pressed by the pressure in the pilot oil passage 44a and located in the left position 8b. When the pressure in the oil passage 47 is higher than the pressure in the oil passage 44, the spool is pressed by the pressure in the pilot oil passage 47a and is positioned at the right position 8c.

  In the brake cylinder 11, when the unlocking hydraulic pressure supply oil passage 55 connected to the unlocking hydraulic chamber 11d is opened to the oil tank 6 (that is, to the atmosphere), the piston rod 11b is extended by the biasing force of the spring 11c (FIG. 1). Then, the rotary shaft 4a of the hydraulic motor 4 is locked. On the other hand, when the hydraulic pressure (unlocked hydraulic pressure) is supplied into the unlocked hydraulic chamber 11d via the unlocked hydraulic pressure supply oil passage 55, the spring 11c is compressed and compressed by the pressure in the unlocked hydraulic chamber 11d so that the piston rod 11b is retracted. It is configured to move to the contraction side (braking release side of the hydraulic motor 4) and release the lock of the hydraulic motor 4. That is, the brake cylinder 11 is configured as a so-called negative brake that locks the rotation of the hydraulic motor 4 when no unlocking hydraulic pressure is supplied and releases the lock when the unlocking hydraulic pressure is supplied. Has been.

  A drain oil passage 61 connected to the oil tank 6 extends from the downstream side (secondary pressure side) of the reducing valve 10 in the unlocking hydraulic supply oil passage 55, and the first throttle 13 is interposed in the middle of the drain oil passage 61. Yes. The first throttle 13 can only move the piston rod 11b to the contraction side when the hydraulic motor 4 rotates, that is, when hydraulic pressure (unlocked hydraulic pressure) is supplied into the unlocked hydraulic pressure supply oil passage 55. Is generated in the unlocking hydraulic chamber 11d. As shown in FIG. 1, a drain oil passage 62 extends from the hydraulic motor 4, and the drain oil passage 61 extends from the unlocking hydraulic chamber 11 d of the brake cylinder 11 (however, downstream of the first throttle 13). Have joined.

  Next, the operation of the control device for the hydraulic motor 4 will be described. First, the case where the spool of the manual switching valve 7 is located at the neutral position 7a will be described. Thus, when the spool of the manual switching valve 7 is located at the neutral position 7a, the pressure oil from the hydraulic pump 5 is blocked by the P port of the manual switching valve 7, and the A port, B port and T port are Since the oil tank 6 is opened via the oil passage 42, no pressure oil is supplied to either the oil passage 43 or the oil passage 46, and the hydraulic motor 4 does not rotate. At this time, the unlocking hydraulic pressure supply oil passage 55 is opened to the oil tank 6 via the hydraulic pilot switching valve 8, the oil passage 51, the oil passage 43, the manual switching valve 7 and the oil passage 42. The piston rod 11b extends by being biased by the spring 11c, and the rotating shaft 4a of the hydraulic motor 4 is locked. At this time, the unlocking hydraulic chamber 11d of the brake cylinder 11 is opened to the oil tank 6 via the drain oil passage 61, so that pressure remains in the unlocking hydraulic chamber 11d and the hydraulic motor 4 is locked by the brake cylinder 11. A situation in which it becomes impossible is avoided. At this time, the unlocking hydraulic supply oil passage 55 is also opened to the oil tank 6 via the hydraulic pilot switching valve 8, the oil passage 51, the oil passage 43, the manual switching valve 7 and the oil passage 42 as described above. The residual pressure in the unlocking hydraulic chamber 11d is also removed from the path.

  Next, the case where the spool of the manual switching valve 7 is switched from the neutral position 7a to the left position 7b in FIG. 1 will be described. Thus, when the spool of the manual switching valve 7 is switched from the neutral position 7a to the left position 7b, the pressure oil from the hydraulic pump 5 passes from the P port of the manual switching valve 7 through the A port to the oil path 43. 44, the check valve CV1 is pushed open to enter the oil passage 45, and the hydraulic motor 4 is rotated in the forward direction. The pressure oil that has rotated the hydraulic motor 4 becomes low-pressure hydraulic oil and reaches from the oil passage 48 to the oil passage 54 (the check valve CV2 is closed and does not communicate with the oil passage 47). In a state where the spool is located at the left position 7b, the oil passage 47 is opened to the oil tank 6 through the oil passage 46, the manual valve 7 and the oil passage 42, and the spool of the hydraulic pilot switching valve 8 is in the pilot oil passage 44a. 1 is located at the left position 8b in FIG. 1, the hydraulic oil whose pressure in the oil passage 54 has dropped is the fourth port P4 → second port P2 → oil passage 52 of the hydraulic pilot switching valve 8. → Oil path 46 → B port of manual switching valve 7 → T port → Return to oil tank 6 via oil path 42. In the state where the spool of the manual switching valve 7 is located at the left position 7b as described above, the pressure oil from the hydraulic pump 5 flows from the oil passage 43 to the oil passage 44 and simultaneously flows to the oil passage 51, Furthermore, since the first port P1 of the hydraulic pilot switching valve 8 → the fifth port P5 → the unlocking hydraulic pressure supply oil passage 55 → the brake cylinder 11 unlocking hydraulic chamber 11d, the piston rod 11b of the brake cylinder 11 is connected to the spring 11c. It moves in the contraction direction against the urging force, and the lock of the rotating shaft 4a of the hydraulic motor 4 is released. Note that the pressure supplied into the unlocking hydraulic chamber 11d is the pressure adjusted by the reducing valve 10 (pressure smaller than the discharge pressure of the hydraulic pump 5).

  Next, the case where the spool of the manual switching valve 7 is switched from the neutral position 7a to the right position 7c in FIG. 1 will be described. Thus, when the spool of the manual switching valve 7 is switched from the neutral position 7a to the right position 7c, the pressure oil from the hydraulic pump 5 passes from the P port to the B port of the manual switching valve 7 through the oil path 46. 47, the check valve CV2 is pushed open to enter the oil passage 48, and the hydraulic motor 4 is rotated in the reverse direction. The pressure oil obtained by rotating the hydraulic motor 4 becomes a low-pressure hydraulic oil and reaches the oil path 53 from the oil path 45 (the check valve CV1 is closed and does not communicate with the oil path 44). In a state where the spool is located at the right position 7c, the oil passage 44 is opened to the oil tank 6 via the oil passage 43, the manual switching valve 7 and the oil passage 42, and the spool of the hydraulic pilot switching valve 8 is connected to the pilot oil passage 47a. 1 is located at the right position 8c in FIG. 1, the hydraulic oil whose pressure in the oil passage 53 has dropped is the third port P3 → the first port P1 → the oil passage of the hydraulic pilot switching valve 8. 51 → Oil passage 43 → A port of manual switching valve 7 → T port → Oil passage 42 is returned to the oil tank 6. In the state where the spool of the manual switching valve 7 is located at the right position 7c in this way, the pressure oil from the hydraulic pump 5 flows from the oil passage 46 to the oil passage 47 and simultaneously flows to the oil passage 52, Further, since the second port P2 of the hydraulic pilot switching valve 8 → the fifth port P5 → the unlocking hydraulic pressure supply oil passage 55 → the brake cylinder 11 unlocking hydraulic chamber 11d, the piston rod 11b of the brake cylinder 11 is connected to the spring 11c. It moves in the contraction direction against the urging force, and the lock of the rotating shaft 4a of the hydraulic motor 4 is released.

  As described above, in the control device for the hydraulic motor 4 shown in the above embodiment, the forward / reverse rotation operation and stop of the hydraulic motor 4 can be performed by the switching operation of the manual switching valve 7 and when the hydraulic motor 4 is not operated. Since the rotary shaft 4a is locked by the brake cylinder 11, even when the hydraulic motor 4 is not supplied with hydraulic pressure and its operation is stopped, the heavy object suspended by the hydraulic winch 1 is dropped. There is no.

  The brake device of the hydraulic motor 4 provided in the control device locks the rotating shaft 4a when the hydraulic motor 4 is not operated, and releases the lock when unlocking hydraulic pressure is supplied into the unlocking hydraulic chamber 11d. The brake cylinder 11 to be operated, the lock release hydraulic pressure supply oil passage 55 connected to the lock release hydraulic chamber 11d of the brake cylinder 11, and the hydraulic pressure for supplying the lock release hydraulic pressure into the lock release hydraulic pressure supply oil passage 55 when the hydraulic motor 4 is rotated. The brake device is configured to include the pilot switching valve 8. As described above, this brake device places the unlocking hydraulic chamber 11 d in the oil tank without the unlocking hydraulic pressure being supplied into the unlocking hydraulic chamber 11 d of the brake cylinder 11. 6 is provided with at least two hydraulic chamber opening oil passages that are open to 6. The hydraulic chamber opening oil passage includes (1) a first throttling open oil passage (drain oil passage 61) connected from the unlocking hydraulic chamber 11d to the oil tank 6 via the first throttle 13, and (2) a manual switching valve. 7 is formed by connecting the unlocking hydraulic supply oil passage 55 to the tank 6 via the hydraulic pilot switching valve 8 when the spool 7 is located at the motor rotation stop position (neutral position 7a) where the rotation of the hydraulic motor 4 is stopped. An open oil passage via a hydraulic pilot switching valve (unlocked hydraulic supply oil passage 55 → hydraulic pilot switching valve 8 → oil passage 51 → oil passage 43 → manual switching valve 7 → oil passage 42). For this reason, even when one of the hydraulic chamber opening oil passages is closed due to clogging or the like, the remaining hydraulic pressure in the unlocking hydraulic chamber 11d in the brake cylinder 11 is removed in the other hydraulic chamber opening oil passage, and the hydraulic motor 4 will not fall out of lock. In addition, even if one hydraulic chamber opening oil passage is clogged in this way, the hydraulic motor 4 can be reliably locked when the hydraulic motor 4 is not in operation, so that the safety for work is improved, and a lot of maintenance is performed. There is no need to spend time.

  Next, 2nd Embodiment of the brake device of the hydraulic motor which concerns on this invention is shown. FIG. 2 shows a hydraulic motor control device having a hydraulic motor brake device according to a second embodiment of the present invention. The hydraulic motor control device according to the second embodiment has many components in common with the hydraulic motor control device according to the first embodiment described above, but the first throttle 13 is removed from the unlocking hydraulic chamber 11d of the brake cylinder 11. The drain oil passage 61 connected to the oil tank 6 is not provided and extends from the downstream side of the hydraulic pilot switching valve 8 in the unlocking hydraulic pressure supply oil passage 55 and has a second throttle 14 in the middle. And the point which has the drain oil path 63 connected with the oil tank 6 differs. Therefore, among the components in FIG. 2, the same components as in FIG. 1 use the same reference numerals as in FIG. 1, and the description thereof will be omitted.

  In the hydraulic motor control device according to the second embodiment, since there is no drain oil passage extending from the unlocking hydraulic chamber 11d of the brake cylinder 11 to the oil tank 6 through the first throttle 13, as in the first embodiment. Furthermore, although the residual pressure in the unlocking hydraulic chamber 11 d cannot be removed from this path, the residual pressure can be removed via the drain oil path 63. The second throttle 14 in the drain oil passage 63 moves the piston rod 11b in the contracting direction when the hydraulic motor 4 is rotated, that is, when hydraulic pressure (unlocked hydraulic pressure) is supplied into the oil passage 55. It is provided so that sufficient pressure can be generated in the unlocking hydraulic chamber 11d.

  The brake device for the hydraulic motor 4 provided in the control device locks the rotating shaft 4a when the hydraulic motor 4 is not operated, and locks the same as the brake device for the hydraulic motor according to the first embodiment. When the unlocking hydraulic pressure is supplied into the releasing hydraulic chamber 11d, the brake cylinder 11 that releases the lock, the unlocking hydraulic pressure supply oil passage 55 connected to the unlocking hydraulic chamber 11d of the brake cylinder 11, and the rotation of the hydraulic motor 4 A hydraulic pilot switching valve 8 for supplying unlocking hydraulic pressure is provided in the unlocking hydraulic pressure supply oil passage 55 at the time of operation, and this brake device also releases the lock in the unlocking hydraulic chamber 11d of the brake cylinder 11. Opening of the hydraulic chamber for releasing the unlocking hydraulic chamber 11d to the oil tank 6 in a state where no hydraulic pressure is supplied Road has become at least two provided configuration. The hydraulic chamber opening oil passage is (1) when the spool of the manual switching valve 7 is located at the motor rotation stop position (neutral position 7a) where the rotation of the hydraulic motor 4 is stopped, via the hydraulic pilot switching valve 8. An open oil passage via a hydraulic pilot switching valve formed by connecting the unlocking hydraulic supply oil passage 55 to the oil tank 6 (unlocking hydraulic supply oil passage 55 → hydraulic pilot switching valve 8 → oil passage 51 → oil passage 43 → manual switching. Valve 7 → oil passage 42), and (2) a second branch through open oil that branches from the downstream side of the hydraulic pilot switching valve 8 in the unlocking hydraulic supply oil passage 55 and is connected to the oil tank 6 through the second throttle 14. Road (drain oil path 63). For this reason, also in the brake device of the hydraulic motor 4 according to the second embodiment, an effect can be obtained as in the case of the brake device of the hydraulic motor 4 according to the first embodiment described above.

  Next, a hydraulic motor brake device according to a third embodiment of the present invention will be described. FIG. 3 shows a hydraulic motor control device having a hydraulic motor brake device according to a third embodiment of the present invention. The hydraulic motor control device according to the third embodiment also has many components in common with the hydraulic motor control device according to the first embodiment described above, but the hydraulic pilot switching valve 8 ′ is in the neutral position 8′a of the spool. The first port P1 and the fifth port P5 are blocked and extend from the downstream side of the hydraulic pilot switching valve 8 'in the oil passage 55. The second throttle 14 is provided in the middle and connected to the oil tank 6. The difference is that a drain oil passage 63 is provided. Therefore, among the components in FIG. 3, the same components as in FIG. 1 use the same reference numerals as in FIG. 1, and the description thereof will be omitted.

  In the control apparatus for the hydraulic motor 4 according to the third embodiment, the hydraulic pilot switching valve 8 'blocks the first port P1 and the second port P5 at the neutral position of the spool, respectively. That is, when the spool of the manual switching valve 7 is positioned at the neutral position 7a (at this time, the spool of the hydraulic pilot switching valve 8 'is also positioned at the neutral position), the oil passage 55 is hydraulically hydraulic as in the first embodiment. The oil tank 6 is not opened via the pilot switching valve 8 ′ and the manual switching valve 7, but instead is opened to the oil tank 6 via the drain oil passage 63.

  The brake device of the hydraulic motor 4 provided in the control device locks the rotary shaft 4a when the hydraulic motor 4 is not operated and locks the same as in the brake device of the hydraulic motor according to the first embodiment described above. When the unlocking hydraulic pressure is supplied into the releasing hydraulic chamber 11d, the brake cylinder 11 that releases the lock, the unlocking hydraulic pressure supply oil passage 55 connected to the unlocking hydraulic chamber 11d of the brake cylinder 11, and the rotation of the hydraulic motor 4 A hydraulic pilot switching valve 8 ′ for supplying unlocking hydraulic pressure is provided in the unlocking hydraulic pressure supply oil passage 55 at the time of operation. This brake device is also locked in the unlocking hydraulic chamber 11 d of the brake cylinder 11. The hydraulic pressure in the unlock hydraulic chamber 11d is released to the oil tank 6 in a state where the release hydraulic pressure is not supplied. Chamber open oil passage is in the at least two provided configuration. The hydraulic chamber opening oil passage includes (1) a first throttling open oil passage (drain oil passage 61) connected from the unlocking hydraulic chamber 11d to the oil tank 6 via the first throttling 13, and (2) unlocking hydraulic pressure. This is an open oil passage (drain oil passage 63) that branches from the downstream side of the hydraulic pilot switching valve 8 ′ in the supply oil passage 55 and is connected to the oil tank 6 through the second throttle 14. For this reason, also in the brake device of the hydraulic motor 4 according to the third embodiment, the same effect as that of the brake device of the hydraulic motor 4 according to the first and second embodiments described above can be obtained.

  Although the preferred embodiments of the present invention have been described so far, the scope of the present invention is not limited to those described in the above embodiments. For example, in the above-described embodiment, the hydraulic chamber opening oil passage that releases the hydraulic pressure in the unlocking hydraulic chamber 11d to the oil tank 6 in a state where the unlocking hydraulic pressure is not supplied into the unlocking hydraulic chamber 11d of the brake cylinder 11 is provided. Although two are provided, this hydraulic chamber opening oil passage is not limited to two, and it is sufficient that at least two (three or more) are provided. For example, as the configuration when the number of hydraulic chamber opening oil passages is three, the configuration of the first embodiment and the configuration of the second embodiment described above are combined, and (1) the unlocking hydraulic chamber 11d of the brake cylinder 11 → Drain oil passage 61 (with first throttle 13 in the middle) → oil passage consisting of the passage of oil tank 6 and (2) unlocking hydraulic chamber 11d of brake cylinder 11 → oil passage 55 → hydraulic pilot switching valve 8 → oil passage 51 → oil passage 43 → manual switching valve 7 → oil passage 42 → oil tank 6, and (3) the unlocking hydraulic chamber 11 d of brake cylinder 11 → oil passage 55 → drain oil passage 63 (in the middle It is conceivable to provide three hydraulic chamber opening oil passages with an oil passage consisting of a passage of the second throttle 14) → oil tank 6.

  Further, in the brake device for a hydraulic motor according to the present invention, the valve that controls the rotation operation of the hydraulic motor by supplying and stopping the hydraulic pressure to the hydraulic motor is configured by the manual switching valve in the above-described embodiment. This is an example, and it is not necessarily a manual switching valve. In addition, the valve that supplies the unlocking hydraulic pressure to the brake mechanism when the hydraulic motor rotates is configured as a hydraulic pilot switching valve in the above-described embodiment. However, this is an example, and is not necessarily a hydraulic pilot switching valve. Also good. The same applies to the brake mechanism, and the configuration thereof is not limited to that shown in the above-described embodiment. When the hydraulic motor is not operating, the rotation of the hydraulic motor is locked and the unlocking hydraulic pressure is supplied to the unlocking hydraulic chamber. If it is the structure which cancels | releases the said lock | rock when it is done, it does not necessarily need to have the structure shown in the above-mentioned embodiment.

1 is a hydraulic circuit diagram of a hydraulic motor control device configured to include a hydraulic motor brake device according to a first embodiment of the present invention. FIG. 5 is a hydraulic circuit diagram of a hydraulic motor control device configured to include a hydraulic motor brake device according to a second embodiment of the present invention. FIG. 6 is a hydraulic circuit diagram of a hydraulic motor control device configured to include a hydraulic motor brake device according to a third embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hydraulic winch 4 Hydraulic motor 4a Rotating shaft 5 Hydraulic pump 6 Oil tank 7 Manual switching valve (1st valve)
8 Hydraulic pilot switching valve (second valve)
11 Brake cylinder (brake mechanism)
11d Unlocking hydraulic chamber 13 First throttle 14 Second throttle 55 Oil passage (unlocking hydraulic supply oil passage, hydraulic chamber opening oil passage)
42, 43, 46, 51, 52 Oil passage (hydraulic chamber opening oil passage)
61 Drain oil passage (hydraulic chamber opening oil passage)
63 Drain oil passage (hydraulic chamber opening oil passage)

Claims (4)

A hydraulic motor, a first valve for supplying and stopping hydraulic pressure to the hydraulic motor to control rotation of the hydraulic motor, and a rotary shaft of the hydraulic motor being locked and unlocked when the hydraulic motor is not operating A brake mechanism that releases the lock when unlocking hydraulic pressure is supplied to the hydraulic chamber, an unlocking hydraulic supply oil passage that leads to the unlocking hydraulic chamber of the brake mechanism, and the unlocking operation when the hydraulic motor rotates In a brake device for a hydraulic motor configured to include a second valve that supplies the unlocking hydraulic pressure in a hydraulic supply oil passage,
The unlocking hydraulic chamber of the brake mechanism is provided with at least two hydraulic chamber opening oil passages that open the unlocking hydraulic chamber to an oil tank in a state where the unlocking hydraulic pressure is not supplied. Brake device for hydraulic motor. The hydraulic chamber opening oil passage is connected to the oil tank via the first throttle from the unlocking hydraulic chamber of the brake mechanism, and the first valve opening oil passage is rotated by the spool of the first valve. A second valve open oil passage formed by connecting the unlocking hydraulic pressure supply oil passage to the oil tank via the second valve when the motor rotation stop position is stopped. The brake device for a hydraulic motor according to claim 1. When the hydraulic chamber opening oil passage is located at a motor rotation stop position where the spool of the first valve stops the rotation of the hydraulic motor, the unlocking hydraulic supply oil passage is passed through the second valve. An open oil passage via a second valve formed to be connected to the oil tank, and a second throttle branched from the downstream side of the second valve in the unlocking hydraulic pressure supply oil passage and connected to the oil tank via a second throttle The brake device for a hydraulic motor according to claim 1, further comprising a via-opening oil passage. The hydraulic chamber opening oil passage is connected to the oil tank via the first throttle from the unlocking hydraulic chamber of the brake mechanism, and the second valve in the unlocking hydraulic supply oil passage. The hydraulic motor braking device according to claim 1, further comprising: a second throttle-opening oil passage that branches from a downstream side of the first oil passage and is connected to the oil tank via a second throttle.

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