JP6533882B1 - Lifting machine - Google Patents

Abstract

An object of the present invention is to provide a lifter whose hydraulic motor is not damaged by surge pressure generated inside the hydraulic motor. A lifter 26 is for hoisting a chain 27 by a hydraulic motor 4 driven by a hydraulic pressure supplied from a hydraulic pump 2 via a hydraulic pressure supply passage 3, and is connected to the hydraulic pressure supply passage 3 for hydraulic pressure. According to the delivery amount R, the accumulator 15 is connected to the hydraulic supply passage 3 according to the delivery amount R. The accumulator 15 buffers the impact that occurs, the chain counter 34 measures the delivery amount R of the chain 27, and And a motor-operated valve 18 for selectively setting the connected on state or the disconnected off state. [Selected figure] Figure 1

Description

  TECHNICAL FIELD The present invention relates to a hoist that winds up a chain by a hydraulic motor.

  DESCRIPTION OF RELATED ART Conventionally, the hoisting machine which lowers | hangs a boat | bag from a ship using a hydraulic motor and it rolls up on a ship is known (for example, refer patent document 1). The hydraulic circuit of the lifter of Patent Document 1 includes a first hydraulic path connected to the primary side of the hydraulic motor, a second hydraulic path connected to the secondary side of the hydraulic motor, and the hydraulic pressure from the hydraulic pump. A switching valve is provided to switch which of the first hydraulic path and the second hydraulic path is supplied.

  In this hoisting machine, when the hydraulic motor is in reverse rendering state due to an excessive force at the time of winding up the chain, the switching valve is switched to supply the hydraulic pressure to the second hydraulic path to reverse the hydraulic motor. This prevents damage to the hydraulic motor in the rendering state.

JP, 2002-60185, A

  However, when the anchor chain is impacted during surge in a stormy weather, surge pressure may occur inside the hydraulic motor. In such a case, according to the conventional hoisting machine, the body of the hydraulic motor may be damaged, which may result in the loss of the anchor and the chain.

  An object of the present invention is to provide a lifter in which the hydraulic motor is not damaged by the surge pressure generated inside the hydraulic motor in view of the problems of the prior art.

The lifter according to the present invention is a lifter which winds up a chain by a hydraulic motor driven by a hydraulic pressure supplied from a hydraulic pump through a hydraulic supply passage,
An accumulator connected to the hydraulic pressure supply path for buffering an impact generated on the hydraulic pressure;
A feeding amount measuring unit that measures the feeding amount from the reference position of the chain;
A connection state of the accumulator with respect to the hydraulic pressure supply path is selectively set to an on state in which the accumulator is connected to the hydraulic pressure supply path or an off state in which the connection is released according to the delivery amount. And 1 setting unit,
The hydraulic supply passage is
A first hydraulic path connected to the primary side of the hydraulic motor;
A second hydraulic path connected to the secondary side of the hydraulic motor;
A forward / reverse switching valve for switching whether the hydraulic pressure from the hydraulic pump is supplied to the first hydraulic path or the second hydraulic path;
It is characterized by comprising one relief valve or two or more relief valves disposed in parallel, which relieves the hydraulic pressure to the second hydraulic path when the hydraulic pressure of the first hydraulic path becomes equal to or more than a predetermined value.

  In this configuration, when the anchor is anchored in a stormy weather, an impact is applied to the chain and a surge pressure exceeding the allowable pressure is instantaneously generated inside the hydraulic motor, which may damage the hydraulic motor.

  In this respect, according to the present invention, the surge pressure is buffered by the accumulator by setting the accumulator in the on state in which the accumulator is connected to the hydraulic circuit in advance by the first setting unit, so that damage to the hydraulic motor can be effectively achieved. Can be prevented.

  On the other hand, when the connection state of the accumulator is kept in the ON state, when the chain is wound up to the reference position and the winding is completed, the discharge of oil pressure from the accumulator results in the winding up of the chain and absorption of oil pressure to the accumulator. Due to the feeding of the chain, there is a possibility that the anchor (the hook) repeatedly stops moving up and down.

  Regarding this, when the amount of delivery from the reference position of the chain becomes less than the predetermined value before the completion of the winding-up, the first setting unit releases the connection of the accumulator to the hydraulic circuit and the hydraulic pressure to the accumulator By blocking the movement of the anchor, it is possible to prevent the vertical movement of the anchor at the time of completion of the winding.

  Therefore, according to the present invention, since the first setting portion is provided, it is possible to prevent the vertical movement of the anchor at the completion of the winding up while preventing the damage of the hydraulic motor by the accumulator.

  Further, according to the present invention, when the hydraulic pressure is supplied from the first hydraulic path to the primary side of the hydraulic motor to cause the hydraulic motor to rotate normally and the chain is wound up, the high pressure in the first hydraulic path is relatively long If so, the pressure can be effectively released to the second hydraulic path via one or more relief valves. Therefore, it is possible to prevent the damage to the hydraulic pump more reliably by combining the buffer effect by the accumulator.

  In the present invention, when the delivery amount from the reference position exceeds the first delivery amount, the setting state of the first setting unit is switched from the off state to the on state, and when it becomes less than the first delivery amount. It is preferable to include a first control unit that switches the setting state of the first setting unit from the on state to the off state. According to this, it is possible to automatically realize the prevention of damage to the hydraulic motor due to the buffer effect of the accumulator and the prevention of the vertical movement of the anchor at the completion of the winding-up.

In the present invention, a flow divider functioning as a pressure intensifier for increasing the oil pressure of the oil pressure supply passage;
A second setting unit for setting the hydraulic pressure supply path to an on state via the flow divider and an off state not via the flow divider;
The setting state of the second setting unit is switched from the off state to the on state when the delivery amount exceeds the second delivery amount, and the setting state of the second setting unit is turned on when the delivery amount is less than the second delivery amount. It is preferable to include a second control unit that switches from the state to the off state.

  According to this, the second control unit sets the flow divider to be in the on state to function as a pressure increasing device for the hydraulic pressure supply path when the feeding amount is anchored in a place where the water depth exceeds the second feeding amount. Ru. Therefore, at the start of the subsequent lifting and lowering, the lifting force of the hydraulic motor can be increased while reducing the load of the motor or the like for driving the hydraulic pump.

  As a result, the lifting speed is reduced by the amount by which the lifting force is increased, but it is prevented that the motor or the like is driven for a long time in the overload state, and the lifting amount when the feeding amount exceeds the second feeding amount. You can do this without any problems. After that, when the delivery amount becomes equal to or less than the second delivery amount, the pressure increasing function by the flow divider is turned off, so the lifting force is small, but the lifting speed is performed at a faster lifting speed.

  Therefore, when anchoring at a deep water depth, automatically prevent the motor and the like from being driven for a long time in an overloaded state at the time of lifting, and carry out lifting and lowering promptly at an appropriate lifting speed. Can.

It is a hydraulic circuit diagram showing a hydraulic circuit of a hoist according to an embodiment of the present invention. It is a perspective view which shows a mode that the lifter of FIG. 1 was applied to the ship. It is a perspective view which shows the principal part of the hoist of FIG.

  Hereinafter, embodiments of the present invention will be described using the drawings. FIG. 1 shows a hydraulic circuit of a refrigerator according to an embodiment of the present invention. As shown in FIG. 1, the hydraulic circuit 1 includes a hydraulic motor 4 that lifts the chain by operating with the hydraulic pressure supplied from the hydraulic pump 2 through the hydraulic supply path 3. The hydraulic motor 4 is a variable displacement forward and reverse rotation type.

  The hydraulic pressure supply line 3 includes a first hydraulic line 5 connected to the primary side of the hydraulic motor 4, a second hydraulic line 6 connected to the secondary side of the hydraulic motor 4, and a hydraulic pressure from the hydraulic pump 2. A forward / reverse switching valve 7 is provided to switch which of the hydraulic pressure passage 5 and the second hydraulic pressure passage 6 is to be supplied. Between the first hydraulic passage 5 and the second hydraulic passage 6, two relief valves 8 for relieving the hydraulic pressure to the second hydraulic passage 6 when the hydraulic pressure of the first hydraulic passage 5 exceeds a predetermined value Prepare in parallel. Instead of the two relief valves 8, a large-volume relief valve may be provided with one or more relief valves in parallel.

  A supply connection 9 is connected between the forward / reverse switching valve 7 and the hydraulic pump 2. The forward / reverse switching valve 7 and the reservoir tank 10 are connected by the recovery connection path 11. The forward / reverse switching valve 7 supplies the hydraulic pressure of the supply connection path 9 to the first hydraulic path 5 to recover the hydraulic pressure from the second hydraulic path 6, and the hydraulic pressure of the supply connection path 9 as the second hydraulic path 6. To the reverse direction to recover the hydraulic pressure from the first hydraulic path 5.

  In the supply connection 9, a pressure reducing valve 12 is provided on the hydraulic pump 2 side of the forward / reverse switching valve 7. The pressure reducing valve 12 does not function when the supply connection path 9 is connected to the first hydraulic path 5 or the second hydraulic path 6, and at the time of connection, the hydraulic pressure of the supply connection path 9 passes through the forward / reverse switching valve 7. Are introduced through the balance circuit 13.

  In the first hydraulic path 5 and the second hydraulic path 6, the counterbalance valve 14 is provided on the hydraulic motor 4 side of the forward / reverse switching valve 7. The counter balance valve 14 holds the hydraulic pressure on the primary side at the time of forward rotation of the hydraulic motor 4 and prevents the reverse rotation of the hydraulic motor 4.

  Further, an accumulator 15 is connected to the hydraulic pressure supply path 3 to buffer an impact generated in the hydraulic pressure. That is, between the first hydraulic passage 5 and the second hydraulic passage 6 of the hydraulic pressure supply passage 3, a high pressure selection valve 16 is provided, which is respectively connected to the inlets on both sides. The hydraulic pressure on the high pressure side of the first hydraulic passage 5 and the second hydraulic passage 6 selected by the high pressure selection valve 16 is introduced into the accumulator 15 from the outlet of the high pressure selection valve 16 through the high pressure introduction passage 17.

  The high pressure introduction path 17 is provided with a motor-operated valve 18 that functions as an on-off valve. The motor-operated valve 18 selectively sets the connection state of the accumulator 15 to the hydraulic pressure supply path 3 to the on state in which the accumulator 15 is connected to the hydraulic pressure supply path 3 or the off state in which the connection is released. Function.

  The hydraulic motor 4 is provided with a speed switching valve 19 that switches whether to drive the hydraulic motor 4 at low speed rotation or high speed rotation. The speed switching valve 19 switches whether the hydraulic pressure selected by the high pressure selection valve 16 is supplied to the small capacity side port or the large capacity side port of the hydraulic motor 4. When supplying to the large capacity side port, the hydraulic motor 4 is switched to the low rotation drive, and can be driven by a large driving force suitable for lifting.

  Furthermore, the hydraulic pressure supply path 3 is provided with a flow divider 20 that functions as a pressure booster to increase the hydraulic pressure. In the flow divider 20, an introduction circuit 21 for introducing the hydraulic pressure from the hydraulic pump 2 into the flow divider 20 from the supply connection path 9 of the hydraulic pressure supply path 3 and the hydraulic pressure boosted from the flow divider 20 into the hydraulic pressure supply path 3. A derivation circuit 22 to be derived is connected.

  Motor-operated valves 23 and 24 are provided in the lead-in circuit 21 and the lead-out circuit 22, respectively. A motor-operated valve 25 is provided between the branch point to the lead-in circuit 21 and the junction from the lead-out circuit 22 in the hydraulic pressure supply path 3. The motor operated valves 23, 24, 25 constitute a second setting unit for setting the hydraulic pressure supply path 3 to an on state through the flow divider 20 and an off state not through the flow divider 20.

  FIG. 2 shows a state in which the lifting and lowering operation is performed by the lifting and lowering machine 26 to which the hydraulic circuit 1 is applied. The frying machine 26 includes a sheave chain 28 for winding the shed chain 27 by the hydraulic circuit 1 of FIG. 1 and a shed chain storage 29 for storing the wound shed chain 27. The gearbox 28 is rotated by the hydraulic motor 4 of the hydraulic circuit 1.

  The weir chain 27 is composed of a plurality of weir chains each having a length of 27.5 m. At the time of lifting, the chain 27 is wound up by the lifting machine 26, and as shown in FIG. 2, the shank 31 of the anchor 30 reaches the end of the hose pipe 33 of the ship 32 to be in a convergent state. In the case where the anchor 30 is to be anchored in a deep sea where the water depth exceeds 100 m, it is necessary to feed out three or more anchor chains 27.

  FIG. 3 shows the main part of the lifter 26. As shown in FIG. As shown in FIG. 3, the lifter 26 includes a chain counter 34 that functions as a delivery amount measurement unit that measures the delivery amount of the chain 27 with the above-described convergence state as a reference position. The chain counter 34 includes a drive sprocket 35 integrally rotating with the sheave 28, a driven sprocket 37 driven by the drive sprocket 35 via the roller chain 36, and a pointer 38 sent along the rotational axis of the driven sprocket 37. Prepare. The rotation shaft is screwed with the pointer 38, and constitutes a screw shaft 39 for feeding the pointer 38 according to the amount of rotation.

  On the movement path of the pointer 38, a first limit switch 40 and a second limit switch 41 are provided which are turned on or off by contact with the pointer 38 and output a predetermined signal.

  The first limit switch 40 switches the setting state of the first setting unit from the off state to the on state when the delivery amount R of the chain 27 from the reference position exceeds the first delivery amount r1 (the motor valve 18 is opened) ) Send a signal. In addition, when the first delivery amount r1 or less is reached, a signal to switch the setting state of the first setting unit from the on state to the off state (close the motorized valve 18) is sent.

  When the motor operated valve 18 is switched to the open state or the closed state based on these signals, the accumulator 15 is connected to or disconnected from the hydraulic pressure supply path 3 to perform or stop its function. Therefore, the first limit switch 40 configures a first control unit that switches the setting state of the first setting unit from the off state to the on state or vice versa.

  In FIG. 2, the range in which the setting state by the first setting unit is in the on state is indicated by “ACC ON”, and the range in the off state is indicated by “ACC OFF”.

  The second limit switch 41 switches the setting state of the second setting unit from the off state to the on state when the delivery amount R exceeds the second delivery amount r2 (opens the motor-operated valves 23 and 24 and the motor-operated valve 25). Close) sends a signal, and switches the setting state of the second setting unit from the off state to the on state (closes the motor-operated valves 23 and 24 and opens the motor-operated valve 25) when the second delivery amount is less than Send out. Based on these signals, the motor operated valves 23, 24 are switched to the open state, and the motor operated valve 25 is switched to the closed state, or vice versa.

  This causes the flow divider 20 to switch from not functioning as a pressure intensifier to functioning, or vice versa. Therefore, the second limit switch 41 configures a second control unit that switches the setting state of the second setting unit from the off state to the on state or vice versa.

  In FIG. 2, the range in which the setting state by the second setting unit is in the on state is indicated by “FD ON”, and the range in the off state is indicated by “FD OFF”.

  In this configuration, the pointer 38 of the chain counter 34 abuts on the first limit switch 40 when the delivery amount of the chain 27 reaches the length (27.5 m) of one chain by throwing. At this time, the motor operated valve 18 is opened based on the signal output from the first limit switch 40, and the accumulator 15 is set in the connected state. Thereby, the buffer function by the accumulator 15 becomes effective.

  The pointer 38 of the chain counter 34 abuts on the second limit switch 41 when the delivery amount from the reference position (converged state) reaches the length (82.5 m) of the triple. At this time, the motor operated valves 23 and 24 are opened based on the signal output from the second limit switch 41, and the motor operated valve 25 is closed.

  Thereby, the pressure increasing function by the flow divider 20 is set to the on state. As a result, the hydraulic motor 4 can be driven with a large torque as compared with the case where the flow divider 20 is not functioned as a pressure booster. When anchoring is carried out at a position where the water depth exceeds 100 m, the chain 27 is further drawn out and anchoring is performed.

  After that, when lifting and discharging, the forward / reverse switching valve 7 is set so that the supply connection 9 is connected to the first hydraulic path 5 and the recovery connection 11 is connected to the second hydraulic path 6. Supply of hydraulic pressure is started. As a result, the hydraulic motor 4 starts normal rotation, and winding up of the chain 27 is started.

  When the ship sways due to stormy weather and a momentary impact is applied to the chain 27 during this winding, there is a risk that a large surge pressure may be generated inside the hydraulic motor 4. Therefore, the hydraulic motor 4 is not damaged by the surge pressure.

  Further, even if the chain 27 having a length of 3 (82.5 m) or more is fed out from the convergence state, the flow motor 20 functions as a pressure booster so that the hydraulic motor 4 has a rotational speed of Although reduced, the flow divider 20 is driven with a larger torque than in the case where it does not function as a pressure booster. Therefore, the hydraulic motor 4 can wind up the chain 27 which has been fed out longer than triple (82.5 m) without being overloaded.

  The pointer 38 reaches the second limit switch 41 when the delivery amount R of the chain 27 becomes equal to or less than triple (82.5 m) which is the second delivery amount r2, and the flow divider 20 does not function as a pressure booster. . As a result, the driving torque of the hydraulic motor 4 decreases, but the rotational speed increases. Therefore, the chain 27 whose feeding amount R becomes equal to or less than the second feeding amount r2 is efficiently wound without causing an overload. It can be fried.

  During this time, the accumulator 15 is in a connected state, so even if a momentary shock is applied to the chain 27 due to heavy weather and a large surge pressure is generated inside the hydraulic motor 4, the surge pressure is absorbed instantly by the accumulator 15. Therefore, the hydraulic motor 4 is not damaged.

  By the way, when the accumulator 15 is in the connected state until the convergence state in which the delivery amount R is zero is reached, when the winding-up is completed, the winding-up of the chain 27 by the discharge of the oil pressure from the accumulator 15 and the accumulator 15 are performed. The anchor chain 30 may be stopped after repeatedly moving up and down due to the feeding of the chain 27 by absorption of the hydraulic pressure.

  Then, when the delivery amount R of the chain 27 becomes equal to or less than the first delivery amount r1, the motorized valve 18 is closed based on the signal issued from the first limit switch 40 when the pointer 38 reaches the first limit switch 40. The connection state of the accumulator 15 is set to the off state. This prevents the anchor 30 from repeatedly moving up and down when in the convergence state.

  Here, although the buffer function by the accumulator 15 is stopped by this, since the delivery amount R is equal to or less than the first delivery amount r1, the impact generated on the weir chain 27 by the shaking of the ship is not so large. For this reason, there is no possibility that the hydraulic motor 4 will be damaged by the impact.

  As described above, according to the present embodiment, the first setting means (motor-operated valve 18) is provided for setting the connection state of the accumulator 15 to the hydraulic pressure supply path 3 to the on state or the off state according to the delivery amount R. Therefore, the hydraulic motor 4 can be prevented from being damaged by the surge pressure. In addition, since two relief valves 8 are provided between the first hydraulic path 5 and the second hydraulic path 6, or instead of the two relief valves 8, one or three or more relief valves with a large capacity are relieved. Since the valves are provided in parallel, damage to the hydraulic pump 2 can be prevented more reliably.

  Further, since the motor-operated valve 18 is connected to the outlet of the high pressure selection valve 16 connected to the first hydraulic path 5 and the second hydraulic path 6, the hydraulic pump 2 of the first hydraulic path 5 and the second hydraulic path 6 When a surge pressure occurs on the side supplying the hydraulic pressure to the hydraulic pressure, this can be reliably absorbed by the accumulator 15.

  Further, since the motor-operated valve 18 is switched based on the signal from the first limit switch 40 when the delivery amount R becomes less than the first delivery amount r1, the vertical movement of the anchor 30 at the completion of the hoisting is automatically performed. Can be prevented.

  In addition, since the hydraulic pressure supply passage 3 is provided with the second setting means for setting the on state through the flow divider 20 and the off state not through the flow divider 20, the motor for driving the hydraulic pump 2 etc. The lifting force of the hydraulic motor 4 can be increased while reducing the load on the motor.

  In addition, since the second control unit is provided to switch the setting state of the second setting unit from the off state to the on state or vice versa according to the feeding amount R, the motor and the like are overloaded even when the water depth is deep. It is possible to prevent automatically driving for a long time in the state and perform lift-off without trouble.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this. For example, the chain counter 34 may electronically measure the feed amount of the chain 27.

  DESCRIPTION OF SYMBOLS 1 ... Hydraulic circuit, 2 ... Hydraulic pump, 3 ... Hydraulic supply path, 4 ... Hydraulic motor, 5 ... 1st hydraulic path, 6 ... 2nd hydraulic path, 7 ... Positive / reverse switching valve, 8 ... Relief valve, 9 ... Supply Connection path 10 Reservoir tank 11 Recovery connection path 12 Pressure reduction valve 13 Balance circuit 14 Counter balance valve 15 Accumulator 16 High pressure selection valve 17 High pressure introduction path 18 Motorized valve , 19 ... speed switching valve, 20 ... flow divider, 21 ... introduction circuit, 22 ... derivation circuit, 23, 24, 25 ... motorized valve, 26 ... lifter, 27 ... chain, 28 ... chain, 29 ... chain , 30: anchor, 31: shank, 32: ship, 33: hose pipe, 34: chain counter, 35: driving sprocket, 36: roller chain, 37: driven sprocket, 38: pointer, 39: screw shaft, 40: 40th 1 limit Switch, 41 ... the second limit switch.

Claims (3)

A lifter which winds up a chain by a hydraulic motor driven by a hydraulic pressure supplied from a hydraulic pump through a hydraulic pressure supply passage,
An accumulator connected to the hydraulic pressure supply path for buffering an impact generated on the hydraulic pressure;
A feeding amount measuring unit that measures the feeding amount from the reference position of the chain;
A connection state of the accumulator with respect to the hydraulic pressure supply path is selectively set to an on state in which the accumulator is connected to the hydraulic pressure supply path or an off state in which the connection is released according to the delivery amount. And 1 setting unit,
The hydraulic supply passage is
A first hydraulic path connected to the primary side of the hydraulic motor;
A second hydraulic path connected to the secondary side of the hydraulic motor;
A forward / reverse switching valve for switching whether the hydraulic pressure from the hydraulic pump is supplied to the first hydraulic path or the second hydraulic path;
A relief valve comprising one relief valve or two or more relief valves arranged in parallel for relieving the hydraulic pressure to the second hydraulic path when the hydraulic pressure of the first hydraulic path becomes equal to or higher than a predetermined value.錨.   The setting state of the first setting unit is switched from the off state to the on state when the delivery amount from the reference position exceeds the first delivery amount, and when the first delivery amount falls below the first delivery amount. The lifter according to claim 1, further comprising: a first control unit configured to switch the setting state of the switch from the on state to the off state. A flow divider functioning as an intensifier that increases the oil pressure of the oil pressure supply path;
A second setting unit for setting the hydraulic pressure supply path to an on state via the flow divider and an off state not via the flow divider;
The setting state of the second setting unit is switched from the off state to the on state when the delivery amount exceeds the second delivery amount, and the setting state of the second setting unit is turned on when the delivery amount is less than the second delivery amount. The lifter according to claim 1 or 2, further comprising: a second control unit that switches from the state to the off state.

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