JPH081764Y2 - Rotating cylinder - Google Patents

Description

FIELD OF THE INVENTION The present application relates to a rotary cylinder used for operating a chuck in a machine tool.

Conventional technology By the way, in a conventional general rotary cylinder, a tube body extending in the direction opposite to the piston direction is provided on a disk-shaped rear wall of the cylinder body, and a pair of supply / discharge ports is provided on the outer circumference of the tube body. It was configured to rotatably support the sleeve,
In such a rotary cylinder, the sleeve is arranged behind the rear end surface of the rear wall of the cylinder body, and the entire length of the rotary cylinder becomes long, which is not preferable in terms of space saving and vibration damping effect. It was Therefore, as a rotary cylinder that solves this problem, a piston equipped with a piston rod in the front is slidably fitted in the cylinder body, and a deep fitting hole reaching the inside of the piston rod is provided at the center of the piston. A tube body that is opened to the rear of the cylinder body and projects from the center of the rear wall of the cylinder body in the direction of the piston is inserted into the piston insertion hole so that the front end surface of the tube body is located at an axial position where it almost coincides with the front end surface of the cylinder body. A sleeve having a pair of supply / discharge ports is rotatably supported on this pipe, and a communication passage opening at the front end face of the pipe is bored in the pipe, and the piston rod communicates with the front cylinder chamber. There was a rotary cylinder provided with a communication passage (Japanese Patent Laid-Open No. 60-207706).

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the conventional rotary cylinder, there is an effect that a part of the sleeve is arranged in the cylinder body, so that it is possible to provide a compact rotary cylinder. However, in this rotary cylinder, When a relatively thick pipe that supports the sleeve is inserted into the piston rod, the diameter of the piston rod becomes larger than the diameter of the pipe. In some cases, the piston rod diameter is larger than the center hole diameter of the spindle. In such a case, the front end of the piston rod cannot be thrust into the spindle hole.Therefore, the cylinder body and the spindle must be joined together so that the front end of the piston rod is constantly positioned rearward of the rear end of the spindle. Are connected by
As a result, the amount of protrusion (the cantilever length) from the bearing supporting the rear part of the spindle to the rear end of the rotary cylinder becomes long, and there is a problem that vibration is likely to occur during high speed rotation.

Means for Solving the Problems In the present invention, a piston having a piston rod is fitted in the cylinder body so as to be slidable in the axial direction, and a pair of supply / discharge ports is provided in the cylinder body behind the piston. In a rotary cylinder that rotatably supports a sleeve that is immovable in the axial direction and is rotatably supported, the sleeve is rotatably supported by a distributor body to form a distributor unit, and a fitting hole formed in a rear wall of the cylinder body, The distributor unit is connected to the cylinder body so that the cylinder unit protruding into the piston direction from the mounting flange of the distributor body can be divided into two parts, and the front and rear cylinder chambers in the cylinder body communicate with a pair of supply / discharge ports. One of the communication passages is formed so as to pass through the mounting flange, and the other of the communication passages is formed so as to pass through the cylinder body rear wall from the cylindrical portion.

Operation In the rotary cylinder of the present invention, one side of the communication passage that connects the front and rear cylinder chambers in the cylinder body to the pair of supply / discharge ports passes through the mounting flange, and the other side from the protruding shaft portion of the distributor unit to the cylinder. Since it is installed so as to pass through the rear wall of the main body, the axial length of the cylindrical part of the distributor main body that protrudes in the piston direction becomes extremely short, and as a result, the front end face of the cylinder part is located rearward of the front end face of the piston. The diameter of the piston rod provided in front of the machine is small enough to be able to penetrate into the spindle hole of a small machine tool.

Embodiment FIG. 1 shows an embodiment of the hydraulic rotary cylinder 1. Cylinder unit 2 forming the front part of this rotary cylinder 1
The cylinder body 3 is composed of a casing 4 and a rear wall 5, and a piston 7 having a piston rod 6 is fitted in the cylinder body 3 so as to be slidable in the axial direction. With this piston 7, the cylinder chamber 8 in the cylinder body 3
Is divided into a front cylinder chamber 8a and a rear cylinder chamber 8b,
A storage hole 9 for storing a front end portion of a distributor unit 17, which will be described later, is provided at the rear end of the piston 7. The guide pin 13 guides the piston 7 so as to rotate integrally with the cylinder body 3. A distributor unit to be described later is provided in the center of the rear wall 5.
A fitting hole 14 into which the cylindrical portion 21 of 17 is fitted is provided.

Next, the distributor main body 15 located behind the cylinder unit 2
The distributor unit 17 including the sleeve 16 and the sleeve 16 will be described. The distributor main body 15 is configured by fixing a lid member 20 of a bearing 23a, which will be described later, to a front end of a tube body 18a having a mounting flange 18 on the outer periphery, and a portion protruding from the mounting flange 18 toward the piston 7 is a cylindrical portion 21. It has become. This lid member 20 is
The pressure of the pressurized fluid in the rear cylinder chamber 8b is
23a is prevented. In the distributor body 15,
The bush 22 is integrally attached, and a rod-shaped sleeve 16 having a flange 24 at the rear is supported by two bearings 23a and 23b so as to be rotatable around the center line. On the front side of the flange 24 of the sleeve 16, an oil seal 25 is integrally fixed by a seal pressing ring 26 in a position coaxially with the bearing 23b. Oil seal 25
Is located outside the bearing 23b, the axial length of the sleeve 16 is shortened, and the axial length of the distributor 17 is shortened. The cylinder portion 21 of the distributor unit 17 is fitted into the fitting hole 14 provided in the rear wall 5 of the cylinder body 3, and in this state, the mounting flange 18 of the distributor body 15 is fitted to the rear wall 5 of the cylinder body 3. Clamped with a bolt, the cylinder unit 2 and the distributor unit 17 are connected to each other so that the cylinder unit 2 and the distributor unit 17 can be divided into two without disassembling the details.

Next, the communication between the communication passages of the cylinder unit 2 and the distributor unit 17 is performed as follows. The sleeve
A pair of supply / discharge ports 28 and 29 and a drain port 30 are formed on the outer circumference of the flange 24 of the sixteen. One supply / discharge port 28
The communication passage 31 that connects the rear cylinder chamber 8b and the rear cylinder chamber 8b is composed of the sleeve 16, the bush 22, the mounting flange 18 of the distributor main body 15, and the communication passages 31a, 31b, 31c, and 31d provided in the rear wall 5, respectively. Further, the communication passage 35 for communicating the other supply / discharge port 29 with the front cylinder chamber 8a is a communication passage 35a provided in the sleeve 16, the bush 22, the tubular portion 21 of the distributor main body 15, the rear wall 5 and the casing 4, respectively. , 35b, 35c, 35d and 35e. In this way, since one communication passage 31 passes through the mounting flange 18 and the other communication passage 35 passes through the cylinder portion 21 and the cylinder body rear wall 5, the axial length of the cylinder portion 21 is the communication passage 35. The length can be extremely short as long as only the length can be formed. As a result, the front end face of the cylinder portion 21 of the distributor unit 17 is located rearward of the front end face of the piston 7 at the retracted end position A, and is not located inside the piston rod 6, so that the diameter of the piston rod 6 is small. The diameter can be made small enough to allow it to enter the hole of the spindle 10 of the machine.

The rotary cylinder 1 is connected to the rear end of the spindle 10 of a small machine tool via the joint member 11, but as described above, the piston rod 6 can be made small in diameter and the piston 7 is at the forward end position B. At this time, since the piston rod 6 can be thrust into the hole of the spindle 10, the rotary cylinder 1 can be arranged close to the rear end of the spindle 10. Therefore, the amount of protrusion (the cantilever length) from the bearing that supports the rear portion of the spindle 10 to the rear end of the rotary cylinder 1 is shortened, and the generation of vibration during high-speed rotation is prevented, and the load on the bearing is reduced.

The hydraulic rotary cylinder 1 shown in the present embodiment may be designed without the oil seal 25 to be used as the pneumatic rotary cylinder.

As described above, according to the present application, the tubular portion of the distributor unit is fitted in the fitting hole formed in the rear wall of the cylinder body, and a part of the distributor unit is arranged in the cylinder body. A rotary cylinder can be provided. Further, since the length of the tubular portion of the distributor unit can be made extremely short, the tubular portion can be prevented from reaching the piston rod, and the diameter of the piston rod can be made to be a thickness that can be inserted into the spindle hole of a small machine tool. As a result, when the rotary cylinder is attached to the rear end of the spindle, the rotary cylinder can be brought closer to the rear end of the spindle as much as the piston rod is thrust into the spindle hole when the piston is located at the forward end position. The amount of protrusion (cantilever length) from the bearing supporting the rear part of the spindle to the rear end of the rotary cylinder can be shortened, vibration at high speed rotation can be prevented, and the load on the bearing can be reduced.

Further, since the mounting flange of the distributor unit and the rear wall of the cylinder body are integrally connected to the distributor unit and the cylinder body via bolts so as to be separable into two parts without dividing the respective details, The rotary cylinder that has been assembled can be modified in a short time (cylinder size change, stroke change, check valve without cylinder, change to cylinder with check valve, etc.).

[Brief description of drawings]

FIG. 1 is a sectional view of this embodiment, and FIG. 2 is a left end view of FIG. 1 with a part omitted. 1 ... Rotating cylinder, 3 ... Cylinder body, 5 ... Rear wall, 6 ... Piston rod, 7 ... Piston, 8a, 8b ...
… Front and rear cylinder chambers, 15 …… Distributor body, 16 …… Sleeve, 17 …… Distributor unit, 18 …… Mounting flange, 21…
… Cylinder part, 28,29 …… Supply / exhaust port, 31,35 …… Communication passage

Claims (1)

[Scope of utility model registration request] 1. A piston having a piston rod at the front is fitted in the cylinder body so as to be slidable in the axial direction, and
In a rotary cylinder in which a sleeve having a pair of supply / discharge ports is rotatably supported in the cylinder body behind the piston so as not to move axially and rotatably, the sleeve is rotatably supported in the distributor body to form a distributor unit. Then, the cylinder portion protruding from the mounting flange of the distributor body in the piston direction is fitted into the fitting hole formed in the rear wall of the cylinder body to connect the distributor unit to the cylinder body so as to be separable into two parts. A rotary cylinder characterized in that one of communication passages connecting a front and rear cylinder chambers and a pair of supply / discharge ports passes through a mounting flange, and the other passes through the cylinder portion and a rear wall of a cylinder body.