JPH068770U - Direct acting hydraulic motor for cutting work - Google Patents

Abstract

(57) [Abstract] [Purpose] To always discharge the oil leaking from the shaft of the drive unit to the low pressure side, regardless of whether the hydraulic motor rotates in the forward or reverse direction. [Structure] The drive unit (5, 6) is installed in the motor frame housing chamber (2)
Are housed in close contact with each other and rotatably at a fixed position, and the drive oil passages (7, 8) communicate with the engaged portion from the outside. The main shaft (3) of the drive (5) projects out of the motor frame. This motor frame is equipped with an automatic switching valve (11) consisting of a cylinder (9) and a free piston (10). Each drive hydraulic passage is connected to each end opening (14, 15) and each side opening (16, 17) of the cylinder of the automatic switching valve by each pressure guiding hole (12, 13).
Each shaft accommodating part (18, 19, 20, 21) leading to the accommodating chamber has a leak oil hole (2
2) is connected to the inlet (23) on the cylinder side of the automatic switching valve, and the free piston receives the hydraulic pressure on the high pressure side applied through the pressure guide hole and closes the side opening of this pressure guide hole and lowers the leak oil hole pressure. Communicate with the pressure guiding hole that is on the side.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a direct acting hydraulic motor for cutting work.

[0002]

[Prior art]

 When rotating the hydraulic motor, it is normal to discharge the oil leaking from the shaft of the drive body to the discharge side (low pressure side). However, in the case of left-right bidirectional rotation, the leaked oil cannot be discharged to the press-fitting side because the discharge side (low pressure) and the press-fitting side (high pressure) are opposite. If it is used as it is, the oil seal provided on the shaft will be broken due to the high pressure, and a large amount of leaked oil will be dissipated.

[0003]

[Problems to be solved by the device]

 The present invention is intended to provide a direct-acting hydraulic motor for cutting work in which oil leaking from the shaft of the driving body is always discharged to the low pressure side regardless of whether the rotational direction of the hydraulic motor is normal or reverse. To do.

[0004]

[Means for Solving the Problems]

 A direct-acting hydraulic motor for cutting work according to the present invention accommodates a pair of driving bodies having a main shaft or a sub-shaft in an accommodation chamber of a motor frame so as to be in close engagement with each other and rotatably in a fixed position. This is a type in which a pair of drive oil passages that communicate with each other from the outside are separately provided at the engaging portions of both drive bodies in the storage chamber, and the main shaft projects out of the motor frame.

The motor frame is provided with a cylinder and an automatic switching valve made of a free piston slidably fitted on the cylinder. Each drive hydraulic passage is connected to each end opening and each side opening of the cylinder of the automatic switching valve by each pressure introducing hole. Each shaft storage section that communicates with the storage chamber is connected to the inlet on the cylinder side of the automatic switching valve by a leak oil hole. Then, this free piston receives the hydraulic pressure on the high pressure side applied through one of the pressure guide holes to close the side opening of this one pressure guide hole and to connect the leak oil hole to the other pressure guide hole on the low pressure side. It is designed to let you.

[0006]

[Action]

 A cutting tool is attached to the spindle, and one of the drive oil passages is used as the pressure oil supply side to feed the high pressure oil. The drive body receives oil pressure at its engaging portion and rotates in opposite directions, and the drain oil flows out through the other drive oil passage as an oil drain passage. The high-pressure oil sent to the drive oil passage flows through the pressure guide hole to the automatic switching valve, pushing the free piston to cut off the communication between the pressure guide hole and the cylinder. In this state, the leak oil hole and the pressure guide hole on the low pressure side communicate with each other through the free piston. Drive oil passage, immediately flowing to the low pressure side. If the oil press-fitting direction is reversed, the free piston moves in the opposite direction, and the oil leaking from the shaft accommodating part flows out to the drive oil passage on the oil discharge side.

[0007] The main shaft has a boss portion in the accommodation chamber, and the boss portion slidably engages with one of the driving bodies by a key, and the motor frame supports each end portion of the boss portion. Is installed, and the above-mentioned leakage oil hole communicates with the shaft accommodating part between each bearing and the foil seal on the outer side of the bearing, the main shaft and its drive unit will be separated when thrust is applied to the main shaft. The key relatively slides, and its axial force is supported by the bearing. Therefore, since no force is applied to the axial surface of the driving body, no galling phenomenon occurs on the upper (lower) surface of the storage chamber due to an external force load, and friction is minimal, and high-speed operation is possible. Further, since the thrust bearing is not separately provided, the assembling accuracy is not required, and the problem of the contact of the driving body due to wear does not occur.

[0008]

【Example】

 Reference numeral 1 is a motor frame, and 2 is an accommodation chamber. Reference numeral 3 is a main shaft, and 4 is a sub shaft, which rotate integrally with the driving bodies 5 and 6, respectively. These driving bodies 5 and 6 are of various types such as gears, trochoids, vanes, etc., and are housed in the housing chamber 2 in an engaged state, closely and rotatably at a fixed position. A pair of drive oil passages 7 and 8 which communicate with each other from the outside reach the engaging portions of both drive bodies 5 and 6 of the accommodation chamber 2. The main shaft 3 projects outside the motor frame 1. The above is the normal configuration.

In the case of the present proposal, the following configuration is added. That is, the motor frame 1 is provided with a cylinder 9 and an automatic switching valve 11 including a free piston 10 slidably fitted on the cylinder 9. The drive oil passages 7 and 8 are connected to the end openings 14 and 15 of the cylinder 9 of the automatic switching valve 11 by the pressure guide holes 12 and 13, respectively, and the side openings 16 are further connected. And also lead to 17. The shaft accommodating portions 18, 19, 20 and 21 of the accommodating chamber 2 are connected to the inflow port 23 on the side surface of the cylinder 9 of the automatic switching valve 11 by a leak oil hole 22.

The free piston 10 closes the side opening 16 of the pressure guiding hole 12 when receiving the hydraulic pressure on the high pressure side applied through the pressure guiding hole 12 of the one side, and at the same time, opens the side opening of the pressure guiding hole 13 of the other side. Since 17 opens, the leak oil hole 22 is made to communicate with the other pressure guiding hole 13 on the low pressure side. In the opposite case, the leak oil hole 22 communicates with the pressure guide hole 12 on the low pressure side.

The main shaft 3 has a boss portion 31 inside the accommodation chamber 2. The boss portion 31 is slidably engaged with the one driving body 5 by the key 32. The motor frame 1 is provided with separate bearings 33 and 34 that support the upper and lower ends of the boss 31. The leak oil hole 22 communicates with the shaft accommodating portions 18 and 19 between the bearings 33 and 34 and the oil seals 35 and 36 outside thereof. In the drawing, 37 is a cutting tool.

When the pressure oil is sent to the drive oil passage 7 from above in FIG. 1, the drive bodies 5 and 6 receive the oil pressure and rotate in the direction of the arrow, and the cutting tool 37 attached to the main shaft 3 rotates to rotate the workpiece. To process. A part of the pressure oil flows into the pressure guiding hole 12 and pushes down the free piston 10 of the automatic switching valve 11. Therefore, the free piston 10 closes the side opening 16 of the cylinder 9 and opens the side opening 17. Therefore, the leak oil hole 22 communicates with this side opening 17, and the oil flows out to the low pressure side. It will be clear that the opposite is true if the pressure oil is fed into the drive oil passage 8 from below in FIG.

When an axial force is applied to the spindle 3 from the bottom to the top in FIG. 2 by the cutting work, this force is supported by the bearing 3 at the upper end of the boss portion 31 of the spindle. In this case, even if the main shaft 3 moves upward, the driving body 5 does not move upward because it stops sliding through the key 32. Therefore, high speed rotation of the main shaft 3 is also possible.

[0014]

[Effect of device]

 According to the present invention, in the forward-reverse rotation type hydraulic motor, the leaked oil from the shaft accommodating portion of the driving body can always be discharged to the low pressure side, so that the high pressure does not damage the oil seal. According to the second aspect, even if an axial force is applied to the main shaft, it is not transmitted to the driving body, so that high speed rotation can be achieved.

[Brief description of drawings]

1 is a sectional view taken along line 1-1 of FIG. 2 showing a specific example of a direct-acting hydraulic motor for cutting work according to the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Motor frame 2 Storage chamber 3 Main shaft 4 Secondary shaft 5 Driving body 6 Driving body 7 Driving oil passage 8 Driving oil passage 9 Cylinder 10 Free piston 11 Switching valve 12 Pressure introducing hole 13 Pressure introducing hole 14 End opening 15 End opening 16 Side Opening 17 Side opening 18 Shaft housing portion 19 Shaft housing portion 20 Shaft housing portion 21 Shaft housing portion 22 Leakage oil hole 23 Inlet port 31 Boss portion 32 Key 33 Bearing 34 Bearing 35 Oil seal 36 Oil seal

Claims (2)

[Scope of utility model registration request] 1. A main shaft in a housing chamber (2) of a motor frame (1)
(3) or a pair of drive bodies (5, 6) having a sub shaft (4) are housed in close engagement with each other and rotatably in a fixed position, and both drive bodies of this storage chamber (2) Direct-acting hydraulic pressure for cutting work in which the main shaft (3) is projected to the outside of the motor frame (1) with a pair of drive oil passages (7, 8) that communicate with each other from the outside at the engaging parts of (5, 6). In the motor, the motor frame (1) is equipped with a cylinder (9) and an automatic switching valve (11) consisting of a free piston (10) slidably fitted to the cylinder (9), and each drive hydraulic path (7, 8) is separate. The pressure guide holes (12, 13) are connected to the separate end openings (14, 15) and the separate side openings (16, 17) of the cylinder (9) of the automatic switching valve (11) for storage. Each shaft accommodating part (18, 19, 20, 21) leading to the chamber (2) has a leak oil hole
The inlet (23) on the cylinder side of the automatic switching valve (11) by (22)
This free piston (10) receives the hydraulic pressure on the high pressure side applied through one of the pressure guiding holes (12) to close the side opening (16) of the one pressure guiding hole and to release the leakage oil hole ( 22) A direct-acting hydraulic motor for cutting work, characterized in that the (22) communicates with the other pressure guide hole (13) on the low pressure side. 2. The main shaft (3) has a boss portion (31) in the accommodating chamber (2), and one driving body is operated by the key (32) at the boss portion (31).
(5) Slidably engages with the motor frame (1)
When the axial force is applied to (3), the main body (3) of the main shaft (3) that moves leaving the drive body (5) by the key (32) so that the drive body (5) does not press against the upper and lower surfaces of the accommodation chamber (2), Separate bearings (33, 34) supporting each end of the boss (31) are installed, and the leak oil hole (22) described above is provided for each bearing (33, 34) and its outer oil seal (35 , 36) are communicated with the shaft accommodating portion (18, 19).