JPH03281110A - Hydraulic circuit having rotating joint - Google Patents

Abstract

PURPOSE:To discharge a leaked oil without an exclusive drain circuit and to restrain the heating of a rotating joint, by collecting the leaked oil from a rotating joint in an oil basin and returning it to a tank with the utilization of the circuit that a pilot check valve is switched to a discharge side. CONSTITUTION:The hydraulic circuit having a rotating joint 12 is composed by containing the change valve which changes over the primary pressure side communicating to the rotating joint 12 and a discharge side circuit, the oil basin 17 which collects the oil leaked from the rotating joint 12 and the check valve unit 39 with a pilot which communicates to the discharging circuit by opening check valves 41, 42 by the primary pressure pilot of the primary pres sure side circuit that the oil basin 17 is changed over by the change valve, and is made to use a drain circuit in common with a discharge side circuit. When a press oil is fed to the primary pressure side circuit with the change valve being switched, one part of the check valve 41 (or 42) is opened by the primary pressure pilot, the oil basin 17 is communicated to the discharge side circuit and the oil is returned to an oil tank. The flow into the oil basin 17 of the leaked oil at the check valve changing time is checked by a one way valve 71.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a hydraulic circuit having a rotary joint for supplying pressure oil to a rotary cylinder or the like.

BACKGROUND OF THE INVENTION Conventionally, in a rotary joint for opening and closing the gripping claw of a spindle chuck of a machine tool, a labyrinth seal is used as shown in FIG. 3, and oil leaking from the seal is returned to the oil tank through a thick drain circuit. However, in pick-off chucks installed on turret tool rests, etc. for loading and unloading workpieces, it is necessary to make the rotary joint part compact to avoid interference with the tooling, and since the cleat rotates, a dedicated drain circuit must be provided. Since this is difficult, contact type seals are used to prevent oil leakage.

Problems to be Solved by the Invention The latter mentioned in the conventional technology uses a contact type seal, which generates a large amount of heat due to rotation, and the rotation speed must be kept low because seizure occurs at high speed rotation. There are problems.

The present invention was developed in view of the problems of the conventional technology, and its purpose is to suppress heat generation at the rotary joint by making it possible to drain leaked oil without a dedicated Torref circuit. It is an object of the present invention to provide a hydraulic concave passage capable of rotating a pick-off main shaft and the like at high speed.

Means for Solving the Problems In order to achieve the above object, the present invention provides a hydraulic circuit having a rotary joint, a switching valve for switching between a source pressure side circuit and a discharge side circuit communicating with the rotary joint, and a hydraulic circuit having a rotary joint. an oil reservoir that collects leaked oil; and a check valve member that opens the check valve and connects the oil reservoir to the discharge side circuit by the source pressure pilot of the source pressure side circuit switched by the cut-off I@ valve, The exhaust circuit is shared with the discharge side circuit.It is therefore preferable to provide a directional valve to prevent backflow from the check valve side to the oil reservoir.

November 1 When the switching valve is switched and pressure oil is supplied to the main pressure side circuit, one check valve opens by the main pressure pilot,
The oil sump into which leaked oil from the rotary joint flows is communicated with the discharge side circuit, and the oil flowing into the oil sump returns to the oil tank through the discharge circuit. When the check valve is switched, leaked oil is prevented from flowing into the oil reservoir by the directional valve.

Example Examples will be described with reference to the drawings.

In Fig. 1 and Fig. 2, the main body 2 of the Binoku off-wheel, Kuyuni/1/1, which is attached to the turret tool rest of the lathe,
The big-off main shaft 6 facing the main shaft side in the Z-axis direction is connected to the bearings 3, 4 .
5, it is rotatably supported on a shaft. big off-1
- 輔(The center hole of the large diameter part of j is formed in the hydraulic cylinder 7,
The piston 8 fitted into the cylinder 7 has a screw 9 on the right side, and an integral draw tube 10 on the left side, with a lock pin 11 engaged. It is designed to rotate with the big off j two axes. A piston rod 9 is fitted into the center hole 6a of the small diameter portion on the right side of the big-off main shaft 6, and a rotating surface between the outer periphery of the small diameter portion and the hole 2a of the main body is formed in the rotary joint 12. The main body is provided with oil seals 1314 at both ends of the hole 2a,
Oil seal 13,1. , I. The upper end of the oil reservoir 17 of the T-shaped hole is open on the lower side of the inner circumferential groove 15.16 carved inside the holes I. And the oil reservoir 17 has a valve seat 71 on the discharge side.
9. A one-way valve 71 is formed with a spring 73 and a one-way valve 71 in which 11 bodies 72 are lightly contacted. ing. Also, the inner circumferential groove 15.1
．． Almost in the center of 6? Ml18.19 is bored, and one end of the groove 1819ζ is open D L
I'm here. Furthermore, there is a groove 1819 in the small diameter part of the big-off shaft 6.
A flow path 232.1 is located at a right angle toward the axis at a corresponding position of 11. Each hole is drilled in the center hole 6 of the big-off spindle.
An oil seal 25 is installed in the center of the flow passages 23 and 24 in a, and an oil seal 26 is also installed on the right side of the oil seal 25.
is installed. U7 oil sole 25 and 26
A flow passage 24 communicates with a hollow l&27 cut in the center of the big-off main shaft 6, and a flow passage 28 communicating with the hollow groove 27 and the left chamber of the cylinder 7 is bored in the big-off main shaft 6. In addition, the center hole 6a of the shaft is hollowed out between the vicinity of the oil seal 25 and the right side wall of the cylinder 7 to form a hole 30 for a flow passage, and the check valve unit 39 is provided with a hole 30 for a flow path. ! ! The channel 21 that passes through the groove 18. Channel 23. The passage 2), which communicates with the chamber 7-1 of the cylinder 7 through the hole 30 and with the valve unit 1-39, is connected to the groove 19. Channel 24, hollow groove 27.
It communicates with the left chamber of the cylinder 7 via a flow path 28.

A chuck 33 is fixed to the tip of the big-off main shaft 6 for holding the gripping claw 33a, and pressurized oil is supplied to the left chamber of the cylinder 7, causing the screw 8 to move to the right and closing the gripping claw 33a. Pressure oil is supplied to the right chamber of the cylinder 7, the piston 8 moves to the left, and the grip claw 33a opens. Furthermore, the center hole of the draw tube 10 is formed in an air cylinder 34, and a piston rod 36, which is integrated with a screw I/N 35 and inserted into the cylinder 34, is biased to retract by a spring 37, and air is supplied to the cylinder 34. When pressurized air is supplied from the flow path 38, the piston rod 36 resists the force of the spring 37.
The tips of the gripping claws 33a protrude into the gripping claws 33a to eject the gripped workpiece.

A check valve unit 39 with a pilot is attached in close contact with the lower end surface 2b of the main body 2. Paiji] Nol-(
(Two valve holes 43 and 44 are bored horizontally in parallel in the frame 40 of the check valve Unino I-39.
3, the joint surface between the large diameter hole 43a on the right side and the small diameter hole 43b on the right side is formed in the valve seat 43c, and the hole 44 is formed in the large diameter hole 44 on the left side.
The joint surface between the small diameter hole 44b and the small diameter hole 44b on the right side is formed in the valve seat 44C.

Valve rods 45 and 46 are fitted into the holes 43 and 44, respectively, and the tapered surfaces of the valve rods are pressed against the valve seats 43c and 44c by springs 49 and 50 interposed between the lids 47 and 48, thereby making the valve A check valve 41,42 is formed which closes. Then, the main body 2 is placed on the left side of the small diameter hole 43b of the valve hole 43.
The flow path 51 that communicates with the flow path 2I communicates with the small diameter hole 43b.
communicates with the large diameter hole 44a of the valve hole 44 through a flow path 52 concentric with the flow path 51. Further, the large diameter hole 43a of the valve hole 43 communicates with the flow path 2) of the main body 2, and the large diameter hole 43a communicates with the small diameter hole 44b of the valve hole 44 through a flow path 54 concentric with the flow path 53. It communicates with the right side. Furthermore, a pipe joint 58 that communicates with the small diameter hole 43b has a small diameter hole 44b.
A pipe joint 59 is provided which communicates with the pipe.

The lower end of the one-way valve 7] of the oil reservoir 17 is communicated with the right side of the small diameter hole 43b of the valve hole 43 through a flow path 55.
The small diameter hole 44b of the valve hole 44 is
It is connected to the left side of. In this way, the oil sump 17 is connected to the pulp hole 43.44 by the flow path 55.56 via the one-way valve 71.
The small diameter holes 43b and 44b are connected to positions near the valve seat. When pressure oil is supplied to the oil reservoir 17 from the pipe joint 58,
As shown in FIG. 2, the spool portion 45a of the valve stem 45 is pushed to open the check valve 41, and the notch groove 45 on the outer periphery of the large diameter portion of the valve stem is opened.
It communicates with the flow path 54 through b. Also, when pressure oil is supplied from the pipe joint 59, the oil reservoir 17 pushes the spool portion 16a of the valve stem 46, causing the check valve 4
2 is opened and communicated with the flow path 52 through the notch groove 46b of the valve stem.

On the other hand, the circuit that supplies pressure oil to the check valve unit 39 is
A source pressure P supplied from a pump device (not shown) is applied to the pipe line 6
2. Pressure reducing valve 63. 3-position electromagnetic switching valve 6 via conduit 64
When the switching valve 65 is switched to the position ■ by energizing the solenoid SOL 1, the port a
communicates with port C, and via pipe line 66 with pipe joint 59 . Further, when the solenoid valve 65 is switched to the ■ position by energizing the solenoid 5OL2, the port a is communicated with the port d, and is communicated with the pipe joint 58 via the conduit 67.

In other words, when both solenoids are de-energized, they are switched to the ■ position, all boats are closed, the circuit is closed, and the movement of the gripping claw 33a is regulated.

Further, in the return circuit for oil discharged from the check valve unit 39, when the switching valve 65 is switched to the 1 position, ports b and d communicate with each other, and communicate with the oil tank T via pipes 67 and 68. When the switching valve 65 is switched to the position ■, port b and port C communicate with each other, and the pipe line 66.6
It is communicated with tank T via 8.

Next, the operation of this embodiment configured as a "lever" will be explained.

The pick-off chuck 33, which is currently attached to the talent tool rest and indexed to the cutting position, has its gripping claws opened, and in this state, the 3-position electromagnetic switching valve 65 is energized to the solenoid SQL 1, and is in the 1-position. It has been switched to
The adjusted source pressure supplied to port a via the pressure reducing valve 63 is communicated with port C, and is sent to the pipe fitting 59 of the check valve unit 39 via the pipe line 66, where the force of the valve stem 46 and the spring 50 is The check valve 42 opens, and the oil leaking from the rotary joint 12 in the oil reservoir 17, which will be described later, opens the sphere 72 of the one-way valve 7I due to the weight of the oil, and flows into the flow path 55. 56 and flows out from the pipe joint 58 through the flow path 52. The pressure oil supplied to the pipe joint 59 is then transferred to the flow path 54. The valve rod 45 reaches the large diameter hole 43a of the valve hole 43 and moves to the left to close the valve seat 43c. During this movement, pressurized oil flows through the flow path 55 from the notch groove 45b until the valve seat 43C is closed. The pressurized oil flows into the oil reservoir 17, pushes up the sphere 72, and closes the one-way valve 71 while the pressure is present, preventing the oil from flowing into the oil reservoir 17. Then, the pressure oil in the flow path 55 is discharged from the notch 46b, and the pressure drops, and the one-way valve 71 is opened by the oil in the oil reservoir. Large diameter hole 43a
Pressure oil passes through channel 53.2) to groove 1! H, passes through the rotary joint 12 and passes through the flow path 24. It passes through the hollow groove 27 and the flow path 28 in the piston rod 9, and then into the cylinder 7! 4. Pistoyu 8, which should not be sent to the room, has been moved to the right side. In this state, pressure oil is leaking from the groove 19 through the gap in the rotary joint 121'), but the oil 11 on both sides is leaking.
Error No. 13.14; Outflow from the outside (prevented)
2. Oil (Flowing in W'1 11 ＼L ~ Force surface ti-710
) Press the sphere 72 1. -17: I-(7 Moe-no-no-0 <
It's 58 years old, and I'm with Tsumede. -, l! The oil flowing out from the pipe T', 58 is connected to the boat d and connected to the boat d.
I'367 il! The pipe is bent and returned to the tank via the solenoid valve's -I meets d and b.

Next, move the turret in the X-axis direction.

) / oh+ -(,,,,...), the gripping claw 334 of the main shaft 1 and the 7 and ri are concentric, and the history 12 and the throat tool rest are Z.
Axial main shaft (! ill +, second movement, IJ++ gripped by the rotating main shaft 7.) When the valve 65 is inserted, the valve 65 is switched to the position B, and the ports 1-b, 1-b, and 1-b are connected to each other. Bow 1-d
The pressure oil passes through the striped pipe 6G connected to the pipe, passes through the pipe joint 58, and is sent to the check valve uniform throat 39. The valve stem 45 is moved to the right against the force of the spring 49, and the thousand-nick valve 41 is moved to the right. If the rotary clasp 12 in the oil reservoir 17 leaks, push open the sphere 72 of the one-way valve 7 and let it pass through the flow path 55.
The flow path 54 which has been switched to the outlet side is 1jTi''. It flows out from the J pipe joint 59. The supplied pressure oil is sent to the flow path 511!.-!:c' Two also δ
, Is it sent to Niura Road 521 person diameter hole 44a? 4 [: move to the right] Then, the valve 44c is closed, and the oil for this movement flows from the notch 46b to the valve seat 44C for the instant until it is closed. It flows into 55 and V "Ura ga fili body 7
2 total 72 ,,,,l--Key-ζ pressure one-way valve 7
1 is closed to prevent oil from flowing into the oil sump j7. Part 1-7
Pressure oil in the llL passage 5655 (1) is discharged through the notch 45b, and the one-way valve 71 is opened by the oil in the oil reservoir. 18 is sent to the bi2.quaf r-axis side via the rotating 12, and the flow path 23
．． Feed into the chamber of cylinder 7 through hole 30:11. 1. ■ The stone 8 moves left Vj L, and closes the gripping claw 33a via the draw force 10. In this state, groove 1
V1 oil i, h rotation 111] in 8 through the gap of
Leakage, oil pool L 7 L, 2; J! j is in j7, but -, -h-opens the valve -Cj! Since the valve 41 is open, the leaked oil is returned to the oil tank through the switched circuit to the outlet side of II. ) When the gripper claw 333 is closed and the rotating crop is gripped, the upper shaft of the quartz rotates in the directions ig + sode sen, ri and il. Next, the main shaft 1,000 l...'! Open the T1'l object in the open-open-jj sentence 2,
Binokumefu Chise, Tsuku 33 grabs the crop + - Ko, Ri L
・・The 7-tooth turret is in the Z-axis direction counter-1-φn+ (!tll
f, move 7 and pull out the workpiece from the spindle.

Utility The present invention is structured as -14,i ('3), so I will write it down next. 2) Deer T.

Ukeboku I''i1 collects the leaking oil from the rotary joint in the oil reservoir Z-),
) valve to output 1 i, : switch - + 4'l rotation +11 river - C leaked oil]', 2, 2, ko, ゛):'danj-jinichi ( With 1), it is possible to recover leaked oil without installing two dedicated circuits for 11/2.゛Is it possible to make a general plan possible and at the same time ensure 1.1? As a result, the heat generation of the rotary joint can be suppressed to a low level, and the allowable rotation speed can be increased.

The second claim is a bi-operation when switching the direction of silica oil.

During the moment when the guttered check valve is completely switched (j≧), the backflow of the oil sump is caused by Y +l-, which causes the oil sole to break)
Members, please prevent the influx into the 4III Uke.

[Brief explanation of the drawing]

Fig. 1 is a hydraulic circuit diagram of the present invention, Fig. 2 is a cutaway diagram of a part of the Pino-off chuck unit and the Pino-off chuck unit, and a cutaway diagram of the valve -L Niso I-, and Fig. 3M is a diagram of the conventional hydraulic circuit. There is +-r. 12...Rotating Kumite 17...Oil sump 41.4.
2 ・1,000-y 7-way valve 65・・Switching valve 71・・−
・Indication of directional valve special language applicant 4 works Director General f'l Heisei I Do M2 I Patent Application No. 8418 2. Name of invention Hydraulic circuit with rotary joint 3. Relationship with each case to be amended.

Claims (2)

[Claims] (1) A switching valve that switches between the source pressure side circuit and the discharge side circuit that communicate with the rotary joint, an oil sump that collects leaked oil from the rotary joint, and a switching valve that connects the oil sump to the source pressure side circuit that is switched by the switching valve. a check valve member that opens the check valve and communicates with the discharge side circuit by a source pressure pilot;
A hydraulic circuit having a rotary joint characterized in that a drain circuit is shared with a discharge side circuit. (2) A hydraulic circuit having a rotary joint according to claim 1, further comprising a one-way valve that prevents backflow from the check valve side to the oil reservoir.