JP2678798B2 - Spindle carrier for multi-axis machine tools - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a device for ensuring high positioning and indexing accuracy of a spindle carrier of a multi-spindle automatic lathe.

(Prior Art) Conventionally, a main shaft is rotatably supported on a drum-shaped carrier at equal intervals on the circumference, and a plurality of tool stands corresponding to the machining positions assigned to each machining step of a product are sequentially sewn. The present invention relates to the structure of a spindle carrier of a multi-spindle automatic lathe that indexes a spindle, positions it, and finishes one product in one cycle of the machine.
Conventionally, there are two configurations of the positioning means for the spindle carrier that determines the relative position between the spindle and the tool base, and one is the dowel pin that moves forward and backward in the radial direction of the spindle carrier, which has been known for a long time. Although it is locked in the pin hole, there is a small gap between the spindle carrier and the large-diameter sliding bearing that rotatably supports the carrier on the circumference. Is hard to guarantee.

The second one was developed to solve the above problems and uses a coupling consisting of three sheets that guarantees self-alignment. It has a spindle axis that is opposite to the spindle carrier axis. It is possible to guarantee the relative position between them with very high accuracy. The specific configuration will be briefly described with reference to FIG. In the configuration that one main coupling that meshes corresponding to two couplings that are in the inner and outer positions on the same circumferential plane is set, and the main coupling moves back and forth in the main carrier axis direction. The main shaft carrier is positioned by meshing with the inner coupling fixed to the main shaft carrier and the outer coupling that is fixed to the main shaft column fixed to the main shaft carrier and positions the main coupling itself. The advantage is that the spindle carrier on the driven side of the index is not lifted during the indexing operation.
Since the spindle carrier diameter is large and the weight itself is large, a rotating bearing is not used for supporting the spindle carrier, but a sliding bearing is mostly used. Therefore, structurally, either the shoulder portion of the inner or outer coupling is in contact with the shoulder portion of any of the fixed examples of the above-described coupling with the sliding bearing as a boundary. Since they are in surface contact with each other, the shoulders of both parts wear due to repeated indexing operation for a long period of time, causing a step, and the relative positional relationship between the couplings of the couplings changes. It may be possible.

(Problems to be Solved by the Invention) The present invention provides a novel device aiming at solving the above-mentioned problems that occur when the latter coupling is used.

(Means for Solving the Problem) Through the back pressure of the fluid in the fluid cylinder that operates the engagement / disengagement of the main coupling, the main carrier is moved in the carrier axial direction in the direction in which the contact between the shoulders is cut off. To 1 /
Floating about 10 mm avoids contact between both shoulders when indexing the spindle carrier.

(Example) Hereinafter, the present invention will be described with reference to the drawings.

Reference numeral 1 denotes a drum-shaped main spindle carrier rotatably supported on a main spindle column 2 of a multi-spindle machine tool through intermittent driving means.
Reference numeral 3 denotes a spindle rotatably supported on the circumference of the spindle carrier 1 at equal intervals, which is indexed in sequence to a predetermined machining position by the rotation of the spindle carrier 1 and driven at an appropriate rotational speed. 4
Is a chuck mounted on the main shaft 3 and holds a workpiece. Reference numeral 5 denotes carrier positioning means for relatively positioning the spindle 3 at a predetermined position after the spindle carrier 1 has been indexed and rotated, and corresponds to two couplings having an inner and outer positional relationship on the same circumferential plane. With a configuration in which one main coupling that meshes with each other is one set, and the main coupling moves back and forth in the direction of one main spindle carrier,
An inner coupling fixed to the spindle carrier 1,
It is fixed to the main spindle column 2 of the fixed example with respect to the main spindle carrier 1, and the main spindle 3 is accurately positioned at a predetermined machining position through the relative opening and closing operation with the outer coupling that positions the fixing of the main coupling itself. It is a guarantee. The specific configuration will be described below. Reference numeral 6 surrounds the axis of the spindle carrier 1 and, via a clamp fluid cylinder 7 arranged on the spindle column 2, through the spindle carrier 1
The main coupling is mounted on the spindle column 2 so as to be movable back and forth in the axial direction, and has a tooth portion 6a on the end surface of the coupling. Reference numeral 8 denotes an inner coupling having a tooth portion 8a which can freely mesh with the tooth portion 6a of the main coupling 6, and is fixed to the outer periphery of the spindle carrier 1. 9
Is an outer coupling that is located outside the outer periphery of the inner coupling 8 on the same circumferential plane and that has tooth portions 9a that can freely mesh in correspondence with the tooth portions 6a of the main coupling 6. Is stuck to. 10 is an index gear fixed to the rear part of the spindle carrier 1,
The spindle carrier 1 is rotated by receiving the transmission of the intermittent driving means, and the spindle 3 is indexed to a predetermined machining position. Reference numeral 11 denotes a shoulder portion 8b of the inner coupling 8 and a corresponding fixed shoulder portion 9b of the outer coupling 9 when the main spindle carrier 1 is rotated.
Just before starting the rotation of the main spindle carrier 1, the main carrier 1 is pushed toward the main coupling 6 side to float so that the clearance N is drawn out between the shoulder portions 8b and 9b. It consists of The reference numeral 12 designates a floating contact which is in contact with the index gear 10 or the rear end face side of the spindle carrier 1 and moves back and forth in the axial direction of the spindle carrier 1 by a stroke equal to the above clearance N, forming a ring on the circumference of the spindle carrier 1 axis. Is located in. 13 is a floating fluid cylinder for pushing the spindle carrier 1 forward of the spindle carrier 1 via the floating seat 12, and 14 is a piston forward movement chamber 7a of the clamp fluid cylinder 7 and a piston forward movement chamber 13a of the floating fluid cylinder 13. When the piston 7A of the clamp fluid cylinder 7 that operates the opening and closing of the main coupling 6 is retracted in the flow path leading to and is separated from both the inner and outer couplings 89,
The fluid having flowed into the piston advancing operation chamber 7a of the clamp fluid cylinder 7 flows through the flow path 14 into the piston advancing operation chamber 13a of the floating fluid cylinder 13, thereby causing the spindle carrier via the floating seat 12 to flow. Press 1 to float in the axial direction.

 Next, the operation of the present invention will be described.

The main spindle carrier 1 is a means for positioning the main spindle at a machining position that is distributed according to the machining process of the product and sequentially bringing it to that position by indexing. In parallel with the indexing and positioning action, the action of the present invention is achieved. explain. Spindle carrier 1
For indexing, the spindle carrier 1 is indexed through the index gear 10 via an intermittent drive means such as a Geneva gear,
At the time of indexing, the main coupling 6 is disengaged from both the inner and outer couplings 8 and 9, and the engagement is released. In order to separate the main coupling 6 from the inner and outer couplings 8 and 9, a fluid is introduced into the piston retreating operation chamber 7b of the clamp fluid cylinder 7 to operate the piston 7A to retract the main coupling 6. When the piston 7A retreats, the piston advancing chamber 7a
By the back pressure of the fluid that has flowed into the fluid, the fluid passes through the flow path 14,
Piston advancing chamber 13a of floating fluid cylinder 13
Flowing into the piston 13A of the floating fluid cylinder 13
Activate Floating for the time being as piston 13A advances 1
2, the main shaft carrier 1 is pushed in the axial direction in which the main coupling 6 moves away from the inner and outer couplings 8 and 9, and the positioning of the main shaft carrier 1 is slightly floated with respect to the relative position. is there.

At this time, a slight gap (N) is formed at the relative position between the shoulder portion 8b of the inner coupling 8 and the shoulder portion 9b of the outer coupling 9 so that the contact relationship between the shoulder portions 8b and 9b of both couplings is broken. Be done. After this, the indexing operation of the spindle carrier 1 starts again, but since there is no contact between the shoulders 8b and 9b, the indexing operation of the spindle carrier 1 is performed smoothly, and since there is no metal contact, wear occurs. Without it, it is possible to ensure high accuracy in the positioning operation described in the next operation operation. The positioning operation of the spindle carrier 1 after indexing will be described. When the valve is switched to the piston advancing operation chamber 7a of the clamp fluid cylinder 7 and the fluid flows in, the piston 7A operates and the main coupling 6 becomes the inner and outer couplings. It advances toward 8 and 9, first, by the floating operation of the spindle carrier 1,
The outer coupling 9 meshes with the inner coupling 8 projecting forward, and further the piston 7A continues, the main coupling 6 moves forward and meshes with the outer coupling 9 while maintaining the relative position of meshing with the inner coupling 8. . In this state, shoulder portions of both the inner coupling 8 and the outer coupling 9
8b and 9b are in a relative positional relationship in which they are in contact with each other and maintain a positioning state. With the forward movement of the clamp fluid cylinder 7,
The spindle carrier 1 is retracted rearward, and the seat ring 12 that is in contact with the spindle carrier 1 is pushed out to return the piston 13A of the floating fluid cylinder 13 to the retracted original position.

From the above, in the present invention, at the time of disconnecting the coupling, the back pressure of the fluid generated by the backward movement of the clamp fluid cylinder is caused to flow into the other floating fluid cylinder side to float the spindle carrier in the axial direction, It is possible to avoid shoulder contact on both the inner and outer couplings. Therefore, during the indexing operation of the spindle carrier, the indexing can be performed smoothly, and since there is no contact between the shoulders, there is no metal wear and high positioning accuracy is guaranteed.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view showing a spindle carrier of a multi-axis machine tool of the present invention and a positioning means thereof, and FIG. 2 is an embodiment of a configuration for effecting the floating of the spindle carrier of the present invention. Is a simplified diagram of Fig. 2 1 ... Spindle carrier, 3 ... Spindle 6 ... Main coupling link, 8 ... Inner coupling 9 ... Outer coupling, 7 ... Clamp fluid cylinder 13 ... Floating fluid Cylinder, 14 ... Flow path

Claims (1)

(57) [Claims] 1. A spindle, which is rotatably supported at equal intervals on the circumference of a spindle carrier, is indexed at a predetermined machining position, and is formed into two couplings having an inner and an outer positional relationship on the same circumferential plane. In a device that positions the relative position between the spindle and the machining position with a pair of corresponding main couplings as a set, a clamp fluid cylinder that activates and deactivates the engagement of the main coupling with respect to the inner and outer couplings. Spindle carrier for a multi-axis machine tool, characterized by having a floating fluid cylinder that is actuated by the back pressure of the fluid and floats the spindle carrier in the axial direction.