JP3738222B2 - Hydraulic circuit of hydraulic rotating device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hydraulic circuit of a hydraulic rotating device that rotates a final one axis with a plurality of hydraulic motors among hydraulic rotating devices such as a tubing device and a hydraulic auger used for foundation works such as construction and civil engineering.
[0002]
[Prior art]
For example, as shown in FIG. 12, a hydraulic rotating device such as a tubing device or a hydraulic auger includes a plurality of hydraulic motors 3 that rotate and drive a uniaxial ring gear 2 via an output shaft pinion 1, and each hydraulic pressure. A hydraulic pump 4 that supplies hydraulic oil to the motor 3, a main supply oil passage 5 that supplies hydraulic oil from the hydraulic pump 4 to each hydraulic motor 3, and a main oil that discharges hydraulic oil from each hydraulic motor 3 to the tank 6. A discharge oil passage 7; and a direction switching valve 8 that is provided in the main supply oil passage 5 and the main discharge oil passage 7 and switches a supply direction of hydraulic oil. The main supply oil passage 5 and the main discharge oil passage 7 There are many configurations having a hydraulic circuit for connecting the branch supply oil passage 9 and the branch discharge oil passage 10 to each hydraulic motor 3 in parallel, and it is applied to various construction methods, but considering the construction efficiency, the rotational load is small. When rotating at high speed and low torque, load There is only required to rotate at a low speed and high torque is greater. In general, a variable displacement hydraulic motor is used as the hydraulic motor 3 and the rotation speed and torque are changed by varying the amount of oil per rotation, but there is a limit to the speed ratio of the variable displacement hydraulic motor.
[0003]
For this reason, as shown in the registered utility model No. 2567312 publication, three or more hydraulic motor pinions are linked to one ring gear and three or more hydraulic motors are connected by one directional switching valve. In the parallel hydraulic circuit that drives in the same direction, a switching valve that can switch the rotation of the hydraulic motor forward and reverse is connected in the middle of the both-side supply and discharge oil passage between the direction switching valve and one hydraulic motor. In the case of speed, the switching valve is switched in the reverse direction, and the hydraulic motor switched in the reverse direction by the ring gear rotated by another hydraulic motor is operated as a pump, and is adjacent to the hydraulic motor acting as the pump. Circulating hydraulic oil to and from the hydraulic motor, canceling the output of the adjacent hydraulic motor, and supplying the entire amount of hydraulic oil from the hydraulic pump to the remaining hydraulic motor, speeding up the remaining hydraulic motor There are things to be rolling.
[0004]
[Problems to be solved by the invention]
However, the above-described structure requires a hydraulic motor paired with a hydraulic motor acting as a pump, and the number of motors that can be effectively used is reduced. For example, even if three or four hydraulic motors are used, high speed can be achieved.・ If you can only switch to two stages at low speed and want to switch to three stages at high speed, medium speed, and low speed, you will need at least 5 hydraulic motors. Requires two hydraulic motors.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic circuit for a hydraulic rotating apparatus capable of fine speed change in a wide range corresponding to the number of motors used.
[0006]
[Means for Solving the Problems]
In order to achieve the above-described object, the present invention provides a plurality of hydraulic motors that rotate and drive one shaft via a power transmission mechanism, a hydraulic pump, and a main supply that supplies hydraulic oil from the hydraulic pump to each hydraulic motor. An oil passage, a main discharge oil passage that discharges hydraulic oil from each hydraulic motor to the tank, and a direction switching valve that is provided in the main supply oil passage and the main discharge oil passage and switches a supply direction of the hydraulic oil, In a hydraulic circuit of a hydraulic rotating device in which a branch supply oil passage and a branch discharge oil passage to each hydraulic motor are connected in parallel to the main supply oil passage and the main discharge oil passage, the main supply oil passage and the main discharge oil passage are connected to the main supply oil passage and the main discharge oil passage. With the exception of the branch supply oil passage and the branch discharge oil passage of at least one hydraulic motor, a switching valve is provided in each of the remaining branch motor oil supply passage and branch discharge oil passage, A bypass oil passage that branches from the branch discharge oil passage of the at least one hydraulic motor is connected to the switching valve of the branch supply oil passage of the remaining hydraulic motor, and the at least one of the switching valves of the branch discharge oil passage of the remaining hydraulic motor. Branch supply oil passage of two hydraulic motors Connect each bypass oil passage that branches off from At the time of forward rotation of the at least one hydraulic motor, the switching valve of the branch supply oil passage is switched to a cross state so that the at least one hydraulic motor rotating forward with the branch supply oil passage of the remaining hydraulic motor The at least one hydraulic motor that is connected to a bypass oil passage that branches from the branch discharge oil passage and in which a part of the hydraulic oil discharged from the branch discharge oil passage of the remaining hydraulic motor to the tank is rotating forward. Is supplied to the branch discharge oil passage of the at least one hydraulic motor as a replenishment of drainage at the time of reverse rotation of the at least one motor, the switching valve of the branch discharge oil passage is switched to the cross state, and the remaining And a bypass oil passage that branches from a branch supply oil passage of the at least one hydraulic motor that is rotating in reverse with the branch discharge oil passage of the hydraulic motor of The at least one hydraulic pressure that reversely rotates as a replenishment of a part of the hydraulic oil discharged from the branch supply oil passage of the pressure motor to the tank by the at least one hydraulic motor that rotates reversely Supplied to the branch supply oil passage of the motor It is characterized by that. The switching valve may be composed of two logic valves.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention is applied to a hydraulic rotating device of a tubing device. First reference example Will be described with reference to FIGS. This reference example is an example using two variable displacement hydraulic motors, As shown in FIG. 4, the tubing device 20 supports a lifting frame 23 by a plurality of thrust cylinders 22 erected on a base frame 21 so that the lifting frame 23 can be lifted and lowered. A hydraulic rotating device 24 and a chuck device are supported on the lifting frame 23. 25.
[0008]
The hydraulic rotating device 24 includes a uniaxial ring-shaped rotating body 26 that is rotatably provided on the elevating frame 23, and two hydraulic motors 27 and 28 (one is not shown) that rotationally drives the rotating body 26. The hydraulic motors 27 and 28 transmit power via an idler 30 to a pinion 29 provided on the output shaft and a ring gear 26 a formed on the outer periphery of the rotating body 26. The rotating body 26 has an insertion hole 32 for the casing tube 31 formed on the inner periphery.
[0009]
The chuck device 25 includes a plurality of chuck cylinders 33 provided on the lifting frame 23, a ring-shaped support frame 34 supported by the chuck cylinder 33, and a ring-shaped chuck frame 35 provided rotatably on the support frame 34. And a wedge-shaped chuck member 36 suspended from the chuck frame 35.
[0010]
The tubing device 20 grips the casing tube 31 inserted through the insertion hole 32 of the rotating body 26 by the lowering of the chuck member 36 due to the reduction of the chuck cylinder 33, and rotationally drives the rotating body 26 by hydraulic motors 27 and 28. While the casing tube 31 is rotated, the elevating frame 23 is moved up and down by the thrust cylinder 22 to push and pull out the casing tube 31.
[0011]
As shown in FIG. 1, the hydraulic circuit of the hydraulic rotating device 24 includes two variable displacement hydraulic motors 27 and 28, a tank 37 that stores hydraulic oil, and each hydraulic motor 27, 28, a variable displacement hydraulic pump 38 that supplies hydraulic oil to the hydraulic oil 28, a main supply oil passage 39 that supplies hydraulic oil from the hydraulic pump 38 to the hydraulic motors 27 and 28, and the hydraulic motors 27 and 28 to the tank 37. A main discharge oil passage 40 that discharges hydraulic oil, a direction switching valve 41 that is provided in the main supply oil passage 39 and the main discharge oil passage 40 and switches the supply direction of the hydraulic oil, and a direction switching valve 41 and a tank 37. And a branch supply oil passage 27a, 28a and branch discharge oil passages 27b, 28b to the hydraulic motors 27, 28 in parallel with the main supply oil passage 39 and the main discharge oil passage 40. Connected The hydraulic motors 27 and 28 are connected to a drain circuit 43 that returns leaked oil from the hydraulic motors 27 and 28 to the tank 37.
[0012]
The main supply oil passage 39 and the main discharge oil passage 40 are replaced by the main supply oil passage 39 and the main discharge oil passage 40 by the switching operation of the direction switching valve 41. Accordingly, the branch supply oil paths 27a and 28a to the hydraulic motors 27 and 28 are replaced with the branch discharge oil paths, and the branch discharge oil paths 27b and 28b are replaced with the branch supply oil paths.
[0013]
Switching valves 44 and 45 are provided in the branch supply oil passage 28a and the branch discharge oil passage 28b of the hydraulic motor 28 branched from the main supply oil passage 39 and the main discharge oil passage 40, respectively. A bypass oil passage 46 branched from the main discharge oil passage 40 is connected to the switching valve 44, and a bypass oil passage 47 branched from the main supply oil passage 39 is connected to the switching valve 45. These bypass oil passages 46 and 47 are branched on the hydraulic pump 28 side from the branch points of the branch supply oil passage 27a and the branch discharge oil passage 27b of the hydraulic motor 38 branching from the main supply oil passage 39 and the main discharge oil passage 40. ing.
[0014]
In the hydraulic rotating device 24, when the switching valves 44 and 45 are in the straight state shown in FIG. 1, the main supply oil passage 39 and the branch supply oil passage 28a of the hydraulic motor 28 communicate with each other, and the main discharge oil passage 40 and the hydraulic motor. 28 branch discharge oil passages 28b communicate with each other, and bypass oil passages 46 and 47 are blocked.
[0015]
In this state, when the direction switching valve 41 is moved to the right in FIG. 1 and the A and B ports of the direction switching valve 41 are set to the left position, the hydraulic oil from the hydraulic pump 38 is supplied from the main supply oil passage 39 to each hydraulic motor 27. , 28 are supplied to the hydraulic motors 27, 28 via the branch supply oil passages 27 a, 28 a, rotate the hydraulic motors 27, 28 to drive the rotating body 26 in the normal direction, and branch the hydraulic motors 27, 28. It returns to the tank 37 through the main oil discharge passage 40 from the oil discharge passages 27b and 28b.
[0016]
Further, when the direction switching valve 41 is moved to the left in FIG. 1 and the A and B ports of the direction switching valve 41 are set to the right position, the main discharge oil passage 40 is connected to the main supply oil passage from the hydraulic pump 38. 39 is replaced by a main discharge oil passage to the tank 37, and hydraulic oil from the hydraulic pump 38 is supplied from the main discharge oil passage 40 through the branch discharge oil passages 27b and 28b of the respective hydraulic motors 27 and 28. , 28, the hydraulic motors 27, 28 are rotated to drive the rotating body 26 in reverse rotation, and the branch supply oil paths 27 a, 28 a of the hydraulic motors 27, 28 are passed through the main supply oil path 39 to the tank 37. Return.
[0017]
Accordingly, since the hydraulic oil from the hydraulic pump 38 is supplied to the hydraulic motors 27 and 28, the rotating body 26 rotates at a low speed and a high torque in the forward or reverse direction according to the operation of the direction switching valve 41.
[0018]
Next, as shown in FIG. 2, the direction switching valve 41 is moved to the right to set the A and B ports of the direction switching valve 41 to the left position, the switching valve 44 is switched to the cross state, and the switching valve 45 is set to the cross state. In the straight state, the hydraulic oil from the hydraulic pump 38 is supplied from the main supply oil passage 39 to the hydraulic motor 27 through the branch supply oil passage 27a of the hydraulic motor 27 as shown by the arrows in the drawing, The motor 27 is rotated to drive the rotating body 26 in the normal direction, and returns from the branch discharge oil passage 27 b of the hydraulic motor 27 to the tank 37 through the main discharge oil passage 40.
[0019]
On the other hand, in the hydraulic motor 28, since the switching valve 44 is in the cross state, the communication between the branch supply oil passage 28a and the main supply oil passage 39 is blocked, and the branch supply oil passage 28a is connected via the bypass oil passage 46. Short circuit with main discharge oil passage 40. Accordingly, hydraulic oil from the hydraulic pump 38 is not directly supplied to the hydraulic motor 28, but the hydraulic motor 28 is rotated by the rotating body 26 via the pinion 29, and the hydraulic oil discharged from the hydraulic motor 28 is As indicated by the arrow in the middle, the oil is circulated from the branch discharge oil passage 28b to the hydraulic motor 28 through the switching valve 45, the main discharge oil passage 40, the bypass oil passage 46, the switching valve 44, and the branch supply oil passage 28a.
[0020]
Further, as shown in FIG. 3, the direction switching valve 41 is moved to the left so that the A and B ports of the direction switching valve 41 are set to the right position, the switching valve 44 is set in a straight state, and the switching valve 45 is switched to perform crossover. In the reverse rotation state, the hydraulic oil from the hydraulic pump 38 flows from the main discharge oil passage 40 serving as the main supply oil passage through the branch discharge oil passage 27b of the hydraulic motor 27 as shown by the arrows in the figure. The hydraulic motor 27 is rotated to rotate the rotating body 26 in the reverse direction, and returns to the tank 37 from the branch supply oil passage 27 a of the hydraulic motor 27 through the main supply oil passage 39.
[0021]
On the other hand, in the hydraulic motor 28, since the switching valve 45 is in the cross state, the communication between the branch discharge oil passage 28b and the main discharge oil passage 40 is cut off, and the branch discharge oil passage 28b passes through the bypass oil passage 47. The hydraulic oil is short-circuited to the main supply oil passage 39 and hydraulic oil is not directly supplied to the hydraulic motor 28, but the hydraulic motor 28 is rotated by the rotating body 26 via the pinion 29 and discharged from the hydraulic motor 28. As shown by the arrows in the figure, the hydraulic oil is hydraulically passed from the branch supply oil passage 28a through the switching valve 44, the main supply oil passage 39, the bypass oil passage 47, the switching valve 45, and the branch discharge oil passage 28b. Circulates to the motor 28.
[0022]
Therefore, in the state of the circuit diagram shown in FIGS. 2 and 3, the hydraulic oil from the hydraulic pump 38 is directly supplied only to the hydraulic motor 27, and the hydraulic oil from the hydraulic pump 38 is not directly supplied to the hydraulic motor 28. The hydraulic motor 28 passes through a circulation circuit that passes through the branch discharge oil passage 28b, the switching valve 45, the main discharge oil passage 40, the bypass oil passage 46, the switching valve 44, and the branch supply oil passage 28a in the forward rotation, and branches in the reverse rotation. A circulation circuit is formed that passes through the supply oil passage 28a, the switching valve 44, the main supply oil passage 39, the bypass oil passage 47, the switching valve 45, and the branch discharge oil passage 28b. For this reason, since only the hydraulic motor 27 rotates and drives the rotating body 26, the rotating body 26 rotates the rotating body 26 by the two hydraulic motors 27 and 28. The circuit diagram shown in FIG. Compared to this state, it rotates at twice the speed and half the torque.
[0023]
At this time, since hydraulic oil having a pressure discharged from the hydraulic motor 27 to the tank 37 circulates in the hydraulic motor 28, the A and B ports of the hydraulic motor 28 have the same pressure (tank pressure). Further, since the bypass oil passages 46 and 47 are branched on the tank 37 side from the branch point of the branch supply oil passage 27a and the branch discharge oil passage 27b of the hydraulic motor 27, the hydraulic oil circulating through the hydraulic motor 28 is circulated. In the meantime, the hydraulic oil that has passed through the filter 42, that is, the hydraulic oil discharged from the hydraulic motor 27 is partially replaced, so that the motor damage due to oil deterioration, dust, and the like can be reduced.
[0024]
5 to 7 are First embodiment In the following embodiment examples, First reference example The same elements as those in FIG. In this embodiment, An example using two hydraulic motors, The bypass oil passage 46 connected to the switching valve 44 is branched from the branch discharge oil passage 27b of the hydraulic motor 27, and the bypass oil passage 47 connected to the switching valve 45 is branched from the branch supply oil passage 27a of the hydraulic motor 27. With this configuration, as in the first embodiment, the hydraulic motors 27 and 28 rotate and drive the rotating body 26 when the switching valves 44 and 45 shown in FIG. 5 are not operated. As shown in FIG. 6, when the switching valve 44 is switched to the cross state in accordance with the forward rotation switching of the direction switching valve 41, the hydraulic motor 28 divides the hydraulic motor 27 as indicated by the arrow in the figure. The hydraulic oil of the tank pressure discharged from the discharge oil passage 27b is sucked and discharged to the tank 37 through the branch discharge oil passage 28b, and no work is performed. Only the hydraulic motor 27 is shown in the circuit diagram of FIG. The rotating body 26 is driven to rotate in the forward direction at twice the speed and half the torque compared to the above state, and the switching valve 45 is set to the cross state in accordance with the reverse rotation switching of the direction switching valve 41 as shown in FIG. When switched, the hydraulic motor 28 sucks in the hydraulic oil of the tank pressure discharged from the branch supply oil passage 27a serving as the discharge oil passage of the hydraulic motor 27 as shown by the arrow in the figure, and discharges the hydraulic motor 28. Since the oil is discharged to the tank 37 through the branch supply oil passage 28a serving as an oil passage, only the hydraulic motor 27 has a speed twice that of the state of the circuit diagram of FIG. The rotating body 26 is driven in reverse rotation with the torque of.
[0025]
Therefore, said First reference example The hydraulic motor serves as a replenishment of a portion of the hydraulic oil discharged from the branch discharge oil passage 28b of the hydraulic motor 28 to the tank 37 during the normal rotation of one motor. The hydraulic oil 27 supplies a part of the hydraulic fluid that is supplied to the branch discharge oil passage 27b and discharged from the branch supply oil passage 28a of the hydraulic motor 28 to the tank 37 when one motor rotates backward. Is supplied to the branch supply oil passage 27a of the hydraulic motor 27.
[0026]
For this reason, most of the hydraulic oil that has passed through the hydraulic motor 27 (hydraulic oil that has passed through the filter 42) has passed through the hydraulic motor 28 as replenishment for the drainage that has been drained by the hydraulic motor 27. Since the hydraulic oil that has merged with a part of the hydraulic oil is supplied via the bypass oil passages 46 and 47, it is possible to reduce damage to the motor due to oil deterioration and dust.
[0027]
The above First Reference Example and First Embodiment Example The switching valve 44, 45 may be driven by any of manual, electric, hydraulic pilot and the like.
[0028]
Figure 8 Second embodiment In this embodiment Is an example of using two hydraulic motors, and is the first embodiment. In this circuit configuration, the switching valves 44 and 45 are switching valves each composed of two logic valves 44a, 44b, 45a and 45b, and the branch supply oil passage 28a of the hydraulic motor 28 is interposed between the logic valves 44a and 44b. The branch discharge oil passage 28b of the hydraulic motor 28 is branched from between the logic valves 45a and 45b. When one motor is rotating forward, the logic valve 44a of the switching valve 44 is shut off and the logic valve 44b is connected. 1 When the motor rotates reversely, the logic valve 45a of the switching valve 45 is shut off and the logic valve 45b is connected to First embodiment Works in the same way.
[0029]
In this way, by using the switching valves 44 and 45 including the two logic valves 44a, 44b, 45a, and 45b, a general switching valve that can cope with the T port of the switching valves 44 and 45 becoming high pressure. You can overcome the small number of types. Moreover, it is possible to cope with a hydraulic circuit with a large flow rate by using a logic valve.
[0030]
FIG. 9 uses three hydraulic motors Second reference example From the main supply oil passage 39, a branch supply circuit 27a of the hydraulic motor 27, a branch supply oil passage 28a of the hydraulic motor 28, and a branch supply oil passage 50a of the hydraulic motor 50 are branched to cause main discharge. From the oil passage 40, a branch discharge circuit 27 b of the hydraulic motor 27, a branch discharge oil passage 28 b of the hydraulic motor 28, and a branch discharge oil passage 50 b of the hydraulic motor 50 are branched.
[0031]
The switching valve 44 is connected to the branch supply oil passage 28 a of the hydraulic motor 28, the switching valve 45 is connected to the branch discharge oil passage 28 b of the hydraulic motor 28, and the switching valve 51 is connected to the branch supply oil passage 50 a of the hydraulic motor 50. A switching valve 52 is provided in each discharge oil passage 50b. A bypass oil passage 46 from the main discharge oil passage 40 is connected to the switching valve 44 and the switching valve 51, and a bypass oil passage 47 from the main supply oil passage 39 is connected to the switching valve 45 and the switching valve 52, respectively. .
[0032]
In this configuration, when the switching valve 51 of the hydraulic motor 50 is switched to the cross state in accordance with the forward rotation switching of the direction switching valve 41, the communication between the branch supply oil passage 50a and the main supply oil passage 39 of the hydraulic motor 50 is interrupted. The branch supply oil passage 50 a is short-circuited with the main discharge oil passage 40 via the bypass oil passage 46. Therefore, the hydraulic oil supplied from the hydraulic pump 38 is supplied to the hydraulic motors 27 and 28, the hydraulic motor 50 rotates through the rotating body 26, and the hydraulic oil discharged from the hydraulic motor 50 is branched and discharged oil passage 50b. From the main oil discharge passage 40 and the bypass oil passage 46 to the branch supply oil passage 50a through the switching valve 51 and circulate to the hydraulic motor 50, the hydraulic motors 27 and 28 have three hydraulic motors 27 and 28. , 50 is rotated at a speed 1.5 times higher than when the rotating body 26 is rotationally driven. The same applies when the switching valve 44 of the hydraulic motor 28 is switched to the cross state without switching the switching valve 51 of the hydraulic motor 50.
[0033]
When both the switching valve 44 and the switching valve 51 are switched to the cross state in accordance with the forward rotation switching of the direction switching valve 41, the hydraulic oil supplied from the hydraulic pump 38 is supplied only to the hydraulic motor 27, and the hydraulic motor 27 rotates three times faster than when the rotating body 26 is rotationally driven by the three hydraulic motors 27, 28, and 50.
[0034]
In the case of reverse rotation switching of the direction switching valve 41, when only the switching valve 52 or the switching valve 45 is switched to the cross state, the switching valve 45 and the switching valve 52 are switched to the cross state at a speed of 1.5 times. Then it rotates at 3 times speed.
[0035]
FIG. In the third embodiment, this embodiment uses three hydraulic motors, A bypass oil passage 47 a from the branch supply oil passage 27 a of the hydraulic motor 27 to the switching valve 45 and a bypass oil passage 47 b to the switching valve 52 are connected. A bypass oil passage from the branch discharge oil passage 27 b of the hydraulic motor 27 to the switching valve 44 is provided. 46a and the bypass oil passage 46b to the switching valve 51 are branched.
[0036]
In this configuration, during one motor normal rotation in which both the switching valve 44 and the switching valve 51 are switched to the cross state in accordance with the forward rotation switching of the direction switching valve 41, the discharge is made from the branch discharge oil passage 27b of the hydraulic motor 27. The hydraulic oil of the tank pressure flows mainly from the bypass oil passage 46 a to the branch supply oil passage 28 a of the hydraulic motor 28 by the suction action of the hydraulic motor 28 rotated through the rotating body 26, and branches through the hydraulic motor 28. It returns to the tank 37 via the main oil discharge passage 40 from the oil discharge passage 28b. On the other hand, the hydraulic motor 50 rotated via the rotating body 26 bypasses the bypass discharge oil passage 27b and the bypass of the hydraulic motor 27 that branches the hydraulic oil mainly discharged from the branch discharge oil passage 50b from the main discharge oil passage 40. A circulation circuit that sucks into the branch supply oil passage 50a from the switching valve 51 via the oil passage 46b is configured. At this time, the hydraulic oil discharged from the branch discharge oil passage 50b is mixed with the hydraulic oil discharged from the hydraulic motor 28 through the branch discharge oil passage 28b in the main discharge oil passage 40 to the branch supply oil passage 50a. Inhaled.
[0037]
In addition, when one motor reversely rotates when both the switching valve 45 and the switching valve 52 are switched to the cross state in accordance with the reverse rotation switching of the direction switching valve 41, the tank pressure discharged from the branch supply oil passage 27a of the hydraulic motor 27 is changed. The hydraulic oil 28 is supplied through the hydraulic motor 28 through the hydraulic motor 28 mainly through the bypass oil path 47a and the branch discharge oil path 28b by the suction action of the hydraulic motor 28 rotated through the rotating body 26. It flows into the passage 28a and returns to the tank 37 through the main supply oil passage 39. On the other hand, the hydraulic motor 50 that is rotated via the rotating body 26 bypasses the bypass supply oil passage 27a and the bypass of the hydraulic motor 27 that mainly branches the hydraulic oil discharged from the branch supply oil passage 50a from the main supply oil passage 39. A circulation circuit that sucks into the branch discharge oil passage 50b from the switching valve 52 via the oil passage 47b is configured. At this time, the hydraulic oil mainly discharged from the branch supply oil passage 50a is mixed with the hydraulic oil discharged from the hydraulic motor 28 through the branch supply oil passage 28a in the main supply oil passage 39 to be branched discharge oil passage. It is sucked into 50b.
[0038]
FIG. In the fourth embodiment, this embodiment also uses three hydraulic motors. The bypass oil passage 47a from the branch supply oil passage 27a of the hydraulic motor 27 to the switching valve 45 is branched, the bypass oil passage 46a from the branch discharge oil passage 27b to the switching valve 44 is branched, and further, the branch supply oil of the hydraulic motor 28 is branched. The bypass oil passage 47b from the passage 28a to the switching valve 52 and the bypass oil passage 46b from the branch discharge oil passage 28b to the switching valve 51 are branched.
[0039]
In this configuration, during one motor forward rotation when both the switching valve 44 and the switching valve 51 are switched to the cross state in accordance with the forward rotation switching of the direction switching valve 41, the discharge is made from the branch discharge oil passage 27b of the hydraulic motor 27. The hydraulic oil of the tank pressure mainly flows from the bypass oil passage 46 a to the branch supply oil passage 28 a of the hydraulic motor 28 by the suction action of the hydraulic motor 28 rotated through the rotating body 26, and passes through the hydraulic motor 28. Due to the suction action of the hydraulic motor 50 that is discharged from the branch discharge oil passage 28b and rotated via the rotating body 26, the hydraulic motor 50 mainly passes through the bypass oil passage 46b and the switching valve 51 and the branch supply oil passage 50a. , And returns to the tank 37 from the branch discharge oil passage 50b through the main discharge oil passage 40.
[0040]
In addition, when one motor reversely rotates when both the switching valve 45 and the switching valve 52 are switched to the cross state in accordance with the reverse rotation switching of the direction switching valve 41, the tank pressure discharged from the branch supply oil passage 27a of the hydraulic motor 27 is changed. The hydraulic oil 28 is supplied through the hydraulic motor 28 through the hydraulic motor 28 mainly through the bypass oil path 47a and the branch discharge oil path 28b by the suction action of the hydraulic motor 28 rotated through the rotating body 26. Due to the suction action of the hydraulic motor 50 that flows into the passage 28a and is rotated through the rotating body 26, it mainly passes through the hydraulic oil 50 via the switching valve 52 and the branch discharge oil passage 50b via the bypass oil passage 47b. The supply oil passage 50a returns to the tank 37 via the main supply oil passage 39.
[0041]
Above In the third and fourth embodiments, the second reference example As described in the above, it is possible to switch to either the switching valve 44 or the switching valve 51 at the time of forward rotation and to switch to either the switching valve 45 or the switching valve 52 at the time of reverse rotation so that the speed is 1.5 times faster. Is possible. Also, Second Reference Example and Third and Fourth Embodiment Examples Also in First Reference Example and First Embodiment Example Even if the circulation circuit is configured in the same manner as described above, a part of the hydraulic oil is replaced instead of a complete closed circuit, so that it is possible to reduce motor damage due to oil deterioration and dust.
[0042]
In addition, when using four or more hydraulic motors, the speed can be switched as many as the number of motors to be used by adopting the same configuration. In this way, fine speed switching can be performed over a wide range with a simple and inexpensive structure in which a switching valve is added to the conventional hydraulic circuit and the hydraulic oil supply / discharge circuit is slightly changed. Also, hydraulic motors that circulate the hydraulic oil during high-speed rotation can be handled with commercial products without using a special motor because the hydraulic oil of tank pressure flows through both the A and B ports.
[0043]
In addition, the hydraulic motor to be used may be a constant displacement motor, but a wider range of speed switching is possible if a variable displacement hydraulic motor is used as in the above embodiment. In the above embodiment, the present invention is applied to the hydraulic rotating device of the tubing device. However, the present invention is not limited to this, and can be applied to a hydraulic rotating device such as a hydraulic auger having the same configuration. It is.
[0044]
【The invention's effect】
As described above, the hydraulic circuit of the hydraulic rotating apparatus according to the present invention has a branch supply of at least one hydraulic motor of a plurality of hydraulic motors connected in parallel to the main supply oil passage and the main discharge oil passage having the direction switching valve. With the exception of the oil passage and the branch discharge oil passage, a switching valve is provided in each of the remaining hydraulic motor branch supply oil passage and branch discharge oil passage, Of the remaining hydraulic motor For switching valve of branch supply oil passage At least one hydraulic motor branch A bypass oil passage that branches off from the discharge oil passage Of the remaining hydraulic motor For switching valve of branch discharge oil passage At least one hydraulic motor branch Since bypass oil passages that branch from the supply oil passage are connected to each other, Of the remaining hydraulic motor When switching the branch supply oil path to the reverse rotation of the direction switching valve Of the remaining hydraulic motor By switching the switching valve of the branch discharge oil passage, the hydraulic oil from the hydraulic pump is supplied to the hydraulic motor that is not provided with the switching valve and the hydraulic motor that is not switching the switching valve, and the switching valve is switched. Since the hydraulic oil of the hydraulic motor is circulated through the bypass circuit and the hydraulic motor whose switching valve is switched is not directly supplied with hydraulic oil from the hydraulic pump, it is switched to the hydraulic motor without the switching valve. The hydraulic motor that is not operated rotates at a higher speed than when it is rotated by the number of hydraulic motors including the hydraulic motor that is switched. Therefore, it is possible to switch the speed as many as the number of motors used at the maximum, add a switching valve to the conventional hydraulic circuit, and change the hydraulic oil supply / discharge circuit slightly. Can do. Further, since the hydraulic oil of the tank pressure flows in both the A and B ports of the hydraulic motor that has been switched, a commercially available product can be used without using a special motor.
[Brief description of the drawings]
[Figure 1] First reference example Hydraulic circuit diagram
FIG. 2 is a hydraulic circuit diagram showing the state of the switching valve during high-speed forward rotation.
FIG. 3 is a hydraulic circuit diagram showing the state of the switching valve during reverse rotation at high speed.
FIG. 4 is a partial sectional view showing the main part of the tubing device.
[Figure 5] First embodiment Hydraulic circuit diagram
FIG. 6 is a hydraulic circuit diagram showing the state of the switching valve during high-speed forward rotation.
FIG. 7 is a hydraulic circuit diagram similarly showing the state of the switching valve during high-speed reverse rotation.
[Fig. 8] Second embodiment Hydraulic circuit diagram
FIG. 9 Second reference example Hydraulic circuit diagram
FIG. 10 Third embodiment Hydraulic circuit diagram
FIG. 11 Fourth embodiment Hydraulic circuit diagram
FIG. 12 is a conventional hydraulic circuit diagram.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 20 ... Tubing apparatus, 26 ... Rotating body, 27, 28, 50 ... Hydraulic motor, 27a, 28a, 50a ... Branch supply oil path, 27b, 28b, 50b ... Branch discharge oil path, 29 ... Pinion, 37 ... Tank, 38 ... Hydraulic pump, 29 ... Main supply oil passage, 40 ... Main discharge oil passage, 41 ... Direction switching valve, 44,45,51,52 ... Switching valve, 46,47 ... Bypass oil passage

Claims (2)

A plurality of hydraulic motors that rotate and drive one shaft through a power transmission mechanism, a hydraulic pump, a main supply oil passage that supplies hydraulic oil from the hydraulic pump to each hydraulic motor, and hydraulic oil from each hydraulic motor to the tank A main discharge oil passage, and a direction switching valve provided in the main supply oil passage and the main discharge oil passage for switching the supply direction of hydraulic oil, and each of the main supply oil passage and the main discharge oil passage. In a hydraulic circuit of a hydraulic rotation device that connects a branch supply oil path and a branch discharge oil path to a hydraulic motor in parallel, the branch supply oil path and the branch of at least one hydraulic motor connected to the main supply oil path and the main discharge oil path Except for the oil discharge passage, switching valves are provided in the branch supply oil passage and the branch discharge oil passage of the remaining hydraulic motor, respectively, and the branch valve of the at least one hydraulic motor is provided in the switch valve of the branch supply oil passage of the remaining hydraulic motor. From the drain oil passage A bypass oil passage for Toki, the rest of the hydraulic motor of the on switch valve of the branch oil discharge passage at least one hydraulic motor of the bypass oil passage branched from the branch supply oil passage for connecting each of said at least one hydraulic motor At the time of normal rotation, the branch supply oil passage switching valve is switched to a cross state to bypass the branch supply oil passage of the remaining hydraulic motor and the branch discharge oil passage of the at least one hydraulic motor that is rotating forward. As a replenishment of a part of the hydraulic oil that is connected to the oil passage and drained from the branch discharge oil passage of the remaining hydraulic motor to the tank by the at least one hydraulic motor that is rotating forward The branch discharge oil passage is supplied to the branch discharge oil passage of the at least one hydraulic motor, and the switching valve of the branch discharge oil passage is set to a cross state when the at least one motor rotates reversely. In other words, a branch oil supply path of the at least one hydraulic motor that is rotating in reverse with a branch discharge oil path of the remaining hydraulic motor is connected to a bypass oil path that branches from the branch oil supply path of the at least one hydraulic motor. A branch supply oil of the at least one hydraulic motor in which a part of the hydraulic oil discharged from the oil passage to the tank is reversely rotated as a replenishment for the drain drop by the at least one hydraulic motor rotating in the reverse direction A hydraulic circuit for a hydraulic rotating device, wherein the hydraulic circuit is supplied to a road . 2. The hydraulic circuit for a hydraulic rotary device according to claim 1, wherein the switching valve is constituted by two logic valves .

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