JPH0526627B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a clamp cylinder suitable for use in index clamping members of machinery.

Prior Art The turret of a turret tool rest of a machine tool such as a lathe is used to determine the necessary tools in accordance with the machining process.
During this indexing, the turret is lifted up from the turret body by hydraulic pressure, disengages the carbyk coupling, and rotates. At the indexing position, the turret is retracted and engages the carbyk coupling again. It is clamped to the turret body. A piston cylinder mechanism is used for this operation.

Problems to be solved by the invention As powerful cutting or large tools are often used, the clamping force of the turret needs to be correspondingly strong, and large-diameter cylinders and pistons must be used to obtain greater force. Ta. When the diameter of the cylinder is increased as described above, the volume becomes large, and the time required for the reciprocating movement of the turret becomes longer, which impairs work efficiency.

Means for Solving Problems A stepped cylinder with a large diameter section in the center and small diameter sections on both sides, and a member that fits into the large diameter section and small diameter sections on both sides of the stepped cylinder and attaches a clamp body. a stepped piston, a flow path that connects a large diameter chamber and a small diameter chamber on the clamp action side of the stepped cylinder from near the end of piston movement in the clamping direction; The small diameter cylinder includes a valve member that communicates the divided chambers of the large diameter portion during unclamping and opens until the flow path communicates during clamping, and a cushion throttle valve that throttles the discharge flow path of the stepped cylinder. Pressure oil is rapidly sent to the chamber in the section, and clamping is performed using the sum of the areas of the chamber in the small diameter section and the chamber in the large diameter section.

Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings. The turret turret of a lathe will be explained as an example.

A turret 2 is horizontally supported on a tool rest 1 by a pivot shaft 3 so as to be movable in the direction of the pivot shaft. A large diameter part 4a at the center of the stepped cylinder 4 for clamping, and a large diameter part 5 fitted into the small diameter parts of the same diameter on both sides thereof.
a, a piston 5 having small diameter portions 5b ₁ and 5b ₂ on both sides is formed concentrically with the pivot shaft 3, and the front small diameter portion 5b ₁ has a large diameter portion of the cylinder near the end of rightward movement of the piston. A notch 5c is cut in the direction of the outer circumferential axis to communicate the chamber _4a1 and the small diameter chamber _4b1 . The rotating shaft 3 includes an indexing disk 6 having a notch cut on its circumference corresponding to the indexing angle of the turret, a gear 7 for rotating the turret, and an indexing angle detector 8 at the rear end.
A dock 9 is provided. Further, a car bicker cup ring 10a is attached concentrically to the back surface of the turret 2, and a counterpart car bik cup ring 10b is fixed concentrically to the opposite surface on the turret 1 side. Furthermore, the piston rod end of the piston 12 fitted into the cylinder 11 for positioning in the direction perpendicular to the index disk 6 serves as a positioning notch 13, which is fitted into the notch of the disk 6 to determine the rough position. The turret turning gear 7 is turned by a hydraulic motor 15 via an intermediate gear 14, and the dog 9 is connected to a proximity switch 16 by means of a carby coupling 10a,
Check the clamp 10b.

The large diameter portion 4a of the stepped cylinder 4 for clamping is connected to the chamber 4 of the front large diameter portion by the large diameter portion 5a of the piston 5.
a ₁ and a rear large-diameter chamber 4a ₂ , both of which are connected to oil passages 20 and 2 via a pilot check valve 17.
1 is connected. The pilot pressure of the pilot check valve 17 is taken from a chamber _4b2 in the rear small diameter portion of the cylinder 4, which will be described later. Further, the chamber _4b1 in the front small diameter portion of the clamping cylinder is communicated with the rear chamber 11a of the cylinder 11 through the flow path 22.
The oil passage 23 of a is connected to the pressure side or the discharge side via a two-position switching solenoid valve 41 and a check valve 42. In addition, the chamber _4b2 in the rear small diameter part of the stepped cylinder for clamping is connected to the two-position switching solenoid valve 4 by the oil passage 24.
1. Connected to the pressure side or the discharge side via a check valve 42. The oil passage 22 of the chamber _4b1 in the front small diameter part and the oil passage 23 of the cylinder 11 are communicated with each other by an oil passage 25 in which a check valve 18 for cranking is inserted. 22 is a side road when it is closed. In addition, the oil passage 21 of the large diameter chamber _4a2 on the rear side is connected to the oil passage 21 through a temperature compensated flow rate restricting valve 19 for the cushion during clamping.
6 is connected to the discharge side. Also cylinder 11
The front chamber 11b is connected to the flow path 24 by an oil path 27.

The oil passages 28 and 29 of the hydraulic motor 15 are connected to the pressure side via a 3-position switching solenoid valve 43 and a check valve 42, and to the discharge side via a temperature compensated flow rate throttle valve 44 and a check valve 42. ing. and flow restrictor valve 4
A bypass circuit 30 for 4 is formed by a temperature-compensated flow rate restrictor 45 and a swing speed high/low switching valve 46 to enable high-speed swing and low-speed swing.

Effect Suppose that turret 2, which is in a clamped state, is commanded to index. In order to unclamp the turret 2, the switching solenoid valve 41 is switched to the position, and the pressure oil is sent from the oil passage 24 to the chamber _4b2 in the rear small diameter part of the clamp cylinder 4, and also to the positioning cylinder 1.
1 to the front chamber 11b. This releases the notch 13 and moves the piston 5 to the left in FIG.
The hydraulic pressure to the chamber _4b2 in the rear small diameter section opens the pilot check valve 17 as pilot pressure, and the leftward movement of the piston pushes out the oil in the chamber _4a1 in the large diameter section on the rear side to the chamber _4a2 in the large diameter section on the rear side. The oil in the front small diameter chamber _4b1 opens the check valve 18 through the oil passages 22 and 25, and is discharged from the oil passage 23 through the check valve 42 (Fig. 2), and is discharged from the oil passage 23 through the check valve 42 (Fig. 2). 10b
is disengaged.

Next, the switching solenoid valve 43 is switched from the neutral position to the shortcut (or) position, and the switching solenoid valve 46 is switched to the position, and pressure oil is sent to the hydraulic motor 15 through the flow path 28, and the intermediate gear 14 and the gear 7
The turret 2 is rotated at high speed together with the rotation shaft 3 via the rotation axis 3, and the switching solenoid valve 43 is set to the position by the index signal from the angle detector 8. During this time, the height switching valve 46 is set to the position, and the return oil of the hydraulic motor 15 is transferred to the flow rate restricting valve 44.
By passing through the turret 2, the turret 2 is decelerated.

The switching solenoid valve 41 is switched to the position, and pressure oil is sent from the flow path 23 to the rear chamber 11a of the cylinder 11 to advance the piston 12 to fit the notch 13 into the index plate 6, and further to the small diameter front side from the oil path 22. It is sent to the chamber _4b1 of the department. As the piston 5 moves to the right (FIG. 3), the oil in the chamber _4b2 in the small diameter part on the rear side is discharged from the oil passage 24, and the oil in the chamber _4a2 on the large diameter part on the rear side is discharged from the oil passage 21 through the pilot check valve 17. It is fed into the chamber _4a1 in the front large diameter section. The oil sent to the front small-diameter chamber _4b1 by the notch 5c before the end of the rightward movement of the piston 5 is also sent to the front large-diameter chamber _4a1 to close the pilot check valve 17. Therefore, the oil in the chamber _4a2 in the rear large diameter portion is discharged through the oil passage 26 and the flow restrictor 19 for the clamping cushion, and the cushioning action during clamping is performed (FIG. 4).

And car bit springs 10a, 10b
are engaged and clamped with a strong force by hydraulic pressure acting on a wide area of the chamber 4a ₁ of the front large diameter portion and the chamber 4b ₁ of the front small diameter portion. The switching solenoid valve 43 to which the clamp confirmation signal is output from the proximity switch 16 is in position.

Embodiment 2 In Fig. 5, the pilot check valve 17 is replaced with a switching solenoid valve 47 that switches between on and _off . The circuit is opened by a command at the same time as the pilot check valve 17 is opened when it is necessary to communicate with the chamber _4a2 . This effect is the same as described above. Note that the switching valve 47 is not limited and can be used as long as it has the same function.

Effects As detailed above, in the present invention, the hydraulic cylinder and piston for pivoting and indexing clamping of the turret, etc., are stepped with small diameter parts on both sides of the large diameter part, so that pressure oil can be sent to the small diameter part to rapidly can be moved. In addition, since the large diameter part and small diameter part on the side that requires a large force, such as when clamping, are communicated at the time of clamping, it is possible to apply pressure oil to the entire area of the cylinder and obtain a large force. This allows rapid movement and strong clamping to be easily obtained without changing the capacity of the hydraulic oil pump. Also, since the large diameter chambers on both sides of the piston are communicated with each other at the predetermined times of clamping and unclamping, the oil in the cylinder can be circulated, eliminating the need for an oil supply tank, resulting in lower costs and space savings. Further, in the first embodiment, since the communication passage is automatically opened and closed only by the pilot check valve, there is no need for a switching command from the piston movement direction stroke detection means.
There is no delay in operation time.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the clamp cylinder of the present invention combined with a turret tool post, Fig. 2 is a diagram showing the state of the cylinder at the start of unclamping, and Fig. 3 is a diagram showing the state of the cylinder at the start of clamping. 4 is a state diagram of the cylinder during clamping, and FIG. 5 is an explanatory diagram showing another embodiment of the on/off valve for the chamber in the large diameter portion of the cylinder. 2... Turret, 3... Rotating shaft, 4... Clamp cylinder, 4a ₁ , 4a ₂ ... Large diameter chamber, 4b ₁ ,
4b ₂ ... Small diameter chamber, 5... Piston, 5a...
Large diameter portion, 5b ₁ , 5b ₂ ... small diameter portion, 17 ... pilot check valve, 18 ... check valve, 19 ... throttle valve, 47 ... switching solenoid valve.

Claims (1)

[Claims] 1. A stepped cylinder having a large diameter portion in the center and small diameter portions on both sides, and a stepped piston having a member that fits into the large diameter portion and small diameter portions on both sides of the stepped cylinder and attaches a clamp body, respectively; a flow path that communicates the chamber of the large diameter section and the chamber of the small diameter section on the clamp action side of the stepped cylinder from near the end of piston movement in the clamping direction; and the large diameter section that is divided into both sides by the stepped piston. a valve member that connects the chambers when unclamping and opens until the flow passages are communicated when clamped; and a cushion throttle valve that throttles the discharge flow passage of the stepped cylinder. A clamp cylinder characterized by rapid feeding and clamping by the sum of the areas of a small diameter chamber and a large diameter chamber.