JP2600017Y2 - Workpiece holding device for machine tools - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a workpiece holding device for a machine tool, and more particularly, to drilling when a workpiece having a small thickness is drilled by a tool such as a drill. The present invention relates to a workpiece holding device that can prevent damage to a tool due to springback of a machined portion after penetration and can perform automatic tool replacement without hindrance.

[0002]

2. Description of the Related Art With respect to a workpiece positioned on a table, a spindle head can be moved horizontally and horizontally (X direction), vertically up and down (Y direction), and in a direction approaching and separating from the workpiece (Z direction). 2. Description of the Related Art There is known a machine tool in which various tools are detachably mounted on a front end of a main shaft rotatably disposed on a head. In this machine tool, a tool such as a face mill (milling cutter) or a drill is automatically changed by an automatic tool changer (A) according to the type of machining of a workpiece.
TC). That is,
For example, when machining the surface or end face of a workpiece such as a flat surface, a curved surface, a groove, a screw, and a gear, a face milling machine is mounted on the main spindle by an automatic tool changer, and the processed surface of the workpiece is positioned. By moving the face mill along the axis, the required end face processing is performed on the workpiece. Also, when performing machining such as drilling, countersinking, female threading, etc. on the workpiece, attach a drill to the spindle with an automatic tool changer and bring the spindle head close to the positioned workpiece. The required drilling is performed on the workpiece.

[0003]

In the drilling by the machine tool, a drill is forcibly pressed against a workpiece by giving a rotating drill an axial feed. is there. Therefore, during drilling, a pressing force (axial thrust) by the drill is inevitably applied to the workpiece. In this case, if a workpiece such as a box frame having a small thickness and poor rigidity is subjected to the above-described drilling, the periphery of the processed portion of the workpiece is bent inward by the axial thrust of the drill. In this case, the axial thrust of the drill is lost after drilling and the processed portion springs back, so that the drill often has a serious problem of breaking. Also,
When a drill is pulled out from a workpiece, a drawback is pointed out that a machined portion of the workpiece is bent outward together with the drill, so that smooth drawing cannot be performed.

Therefore, a proposal has been made to prevent the breakage of the drill due to springback by holding the vicinity of the processed portion of the workpiece in a non-movable manner by a holding member positioned on the front side of the spindle. In this case, in a machine tool configured to exchange various tools such as a drill and a face mill with an automatic tool changer as described above,
When the tool is replaced by the replacement device, the holding member located in front of the spindle interferes with the replacement device, and there is a problem that the tool cannot be automatically replaced.

[0005]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned drawbacks inherent in a machine tool, and has been proposed in order to solve the problem in a favorable manner, and prevents breakage of a tool due to springback of a workpiece. It is another object of the present invention to provide a workpiece holding device capable of automatically changing tools.

[0006]

SUMMARY OF THE INVENTION To overcome the above-mentioned disadvantages,
In order to achieve the intended purpose, the present invention provides a spindle head slidably disposed on a saddle with a spindle rotatably provided, and a tool provided detachably at one end of the spindle to provide a required work to a workpiece. In a machine tool for performing processing, the workpiece is slidably provided on a support member provided on the saddle, and is driven by an actuator provided on the saddle, so that the workpiece can be moved relative to the workpiece.
A moving member which is parallel to advance and retreat the axis of the spindle Te, through the axis intersecting with the moving direction of the moving member is rotatably supported on said moving member, a working position facing the front of the spindle
A holding member movable between a standby position retracted from the front surface of the main shaft, and a moving member disposed on the moving member and moving the moving member forward.
With the movement , the holding member facing the standby position is moved to the operating position.
After moving the holding member to the operating position,
Move forward with the moving member, and
With the retreat, the holding member facing the operating position is moved to the operating position.
After moving the required length integrally with the moving member while facing the position
And an operating mechanism for moving to a standby position after retreating .

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a workpiece holding device for a machine tool according to the present invention. For convenience of description, a direction approaching the workpiece is referred to as “front”, and a direction away from the workpiece is referred to as “back”.

FIG. 1 is a schematic side view of a machine tool according to a preferred embodiment of the present invention, partially cut away. The illustrated machine tool 10 includes a holding frame 14 having a spindle head 12.
Is positioned on a table (not shown) located on the front side of the frame 14 by an appropriate feed mechanism (not shown) composed of, for example, a combination of a ball screw and a nut or a combination of a rack and a pinion. The workpiece 16 is configured to be capable of reciprocating in the horizontal left / right direction (X direction), the horizontal front / rear direction (Z direction), and the vertical up / down direction (Y direction). A saddle 18 is provided on the holding frame 14, and a pair of guide surfaces 18 a, 18 a extending in a direction toward the workpiece 16 are formed on the upper surface of the saddle 18 in parallel at a predetermined interval. The spindle head 12 is slidably disposed on the guide surfaces 18a, 18a (see FIG. 2). The spindle head 12 is processed along the guide surfaces 18a, 18a of the saddle 18 by an appropriate feed mechanism (not shown) including, for example, a combination of a ball screw and a nut or a combination of a rack and a pinion. Proximity to object 16
It is configured to reciprocate in the separating direction (V direction).

As shown in FIG. 1, the spindle head 12 shown in the embodiment is provided with a spindle 20 extending in the V direction so as to be rotatable.
A tool 22 such as a face mill or a drill is detachably attached to an end of the spindle 20 protruding from the front face of the spindle head via an automatic tool changer (not shown). The mounted tool 22 is configured to point at the workpiece 16 positioned on the table. A motor (not shown) is provided inside the spindle head 12, and the spindle 20 is driven to rotate by the motor. Therefore, while rotating the tool 22, the spindle head 12 is moved in X, Y,
By moving the workpiece 16 in the Z direction and the V direction (the direction of the drill axis), the workpiece 16 can be subjected to an end face processing and a drilling processing.

In the saddle 18, both guide surfaces 18a,
As shown in FIG. 2, the spindle head 12
A support member 24 is disposed and fixed so as not to interfere with the main body. A moving member 28 forming a main body of the holding device 26 is provided in a through hole 24a formed in the support member 24 with a moving direction (V
Direction) and is slidably arranged in parallel with (direction). As shown in FIG. 1, a hydraulic cylinder 32 as an actuator is disposed at the rear of the saddle 18 via a bracket 30, and a piston rod 32a of the hydraulic cylinder 32 is provided.
Has one end connected to the rear end of the moving member 28. Accordingly, by urging the hydraulic cylinder 32 in the forward and reverse directions, the moving member 28 moves forward and backward in the V direction. The hydraulic cylinder 32 is used to hold the holding piece 40 (described later) when machining (piercing) the workpiece 16 with the tool 22 described later.
Is hydraulically controlled to always contact the workpiece 16 at a required pressure.

As shown in FIG. 4, a support shaft 34 parallel to the X direction intersecting the moving direction of the moving member 28 is provided at a front end of the moving member 28 extending toward the front side of the supporting member 24.
Are rotatably supported via bearings 36, 36.
A base portion 38a of a lever 38 as a holding member is provided so as to be integrally rotatable at a portion of the support shaft 34 protruding from the moving member 28, and a holding piece 40 is provided at an extended end of the lever 38. Is done. A rack portion 42 a of a rod 42 as an operating member disposed on the moving member 28 is provided at a portion of the support shaft 34 facing the inside of the moving member 28.
A pinion portion 34a that meshes with a (described later) is formed.
Then, the lever 3 is moved through the support shaft 34 under the meshing action of the pinion portion 34a and the rack portion 42a constituting the operating mechanism.
By pivoting 8, the holding piece 40 can be moved between a standby position (FIG. 3) for retracting from the front surface of the spindle 20 and an operating position (FIG. 5) facing the front surface of the spindle 20. I have. The moving member 28 is provided with a stopper 44 which functions to position the lever 38 at the operating position by abutment of the base 38a when the lever 38 is rotated.

As shown in FIG. 3, the moving member 28
A first elongated hole 28a opening to the front side is formed .
A moving body 46 as an operating member is slidably fitted into one elongated hole 28a, and a rod 42 having a predetermined length is integrally formed on the front surface of the moving body 46. And
At the tip of the rod 42, a rack portion 42a that meshes with the pinion portion 34a of the support shaft 34 is formed. No.
A positioning member 48 is disposed at the open end of the one elongated hole 28a, and an elastic member is provided between the positioning member 48 and the moving body 46.
A compression spring 50 as a member is elastically interposed, and constantly biases the moving body 46 rearward. The positioning member 48 has a long hole 48a opened to the rear surface side, and the tip of the rod 42 is slidably received in the long hole 48a.

As shown in FIG. 3, a second elongated hole 28b communicating with the first elongated hole 28a is provided on the upper surface of the moving member 28.
There are bored along its longitudinal direction, the restriction pin 52 projecting from the upper surface of the movable body 46 is adapted to protrude upwardly from the slot 28b. The support member 24
In the upper surface of the through hole 24a, a groove 2 having a required length is provided.
4b is formed, and the restriction pin 52 is configured to slidably face the concave groove 24b. And the lever 3
With the position of the movable member 8 at the standby position shown in FIG. 3, the movable body 46 is held at a position where the regulating pin 52 contacts the rear end of the concave groove 24b under the elastic force of the compression spring 50. ing. Also, the second elongated hole 28b of the moving member 28
Are positioned so as to extend a required length behind the regulating pin 52 in a state where the regulating pin 52 is in contact with the rear end of the concave groove 24b. That is, when the moving member 28 is moved forward by urging the hydraulic cylinder 32 in the forward direction (the direction in which the piston rod 32a extends from the barrel),
Until the rear end of the second elongated hole 28b contacts the regulation pin 52, the moving body 46 and the rod 42 are held at the position where the regulation pin 52 contacts the rear end of the concave groove 24b. At this time, the lever 38 is rotated clockwise under the engagement of the pinion portion 34a and the rack 42a.

[0014]

Next, the operation of the holding device according to the embodiment will be described. A case in which a drill 22 is mounted on the main shaft 20 and a hole is formed in the workpiece 16 will be described.

First, the workpiece 16 is positioned and fixed to the table with its machined surface facing the drill 22 attached to the main shaft 20. At this time, the spindle head 12
Are waiting at a position separated from the workpiece 16 as shown in FIG. The moving member 28 of the holding device 26 stands by at a position separated from the workpiece 16, and the lever 38 disposed on the moving member 28
Faces the standby position, which has been evacuated from the front of the.

Urges the hydraulic cylinder 32 in the forward direction,
The moving member 28 is moved forward with respect to the support member 24.
At this time, the support shaft 34 moves forward integrally with the moving member 28, while the rod 42 and the moving body 46 move under the elasticity of the compression spring 50 so that the regulating pin 52
Is held at a position in contact with the rear end of the concave groove 24b. That is, the pinion portion 34a of the support shaft 34 moves with respect to the rack portion 42a positioned, and the support shaft 34 and the lever 38
Turns clockwise. When the lever 38 rotates by a required angle and the base 38a comes into contact with the stopper 44 provided on the moving member 28, as shown in FIG. It is positioned at an operating position facing in parallel with the processing surface of the workpiece 16.

When the moving member 28 further moves forward by the urging of the hydraulic cylinder 32, the second
The regulating pin 52 of the moving body 46 is provided at the rear end of the elongated hole 28b.
Then, the rod 42 and the moving body 46 move integrally with the moving member 28 (see FIGS. 5 and 6). At this time, the rack portion 42a is urged by the elasticity of the compression spring 50 via the pinion portion 34a in a direction in which the lever 38 comes into contact with the stopper 44, and the lever 38 moves while being held at the operating position. Thereby, the holding piece 4
0 abuts in parallel with the workpiece 16 adjacent to the part to be machined by the drill 22, as shown in FIG. The hydraulic cylinder 32 is controlled so that the holding piece 40 always contacts the workpiece 16 at a required pressure.

Next, by rotating the drill 22 attached to the tip of the spindle 20 by the motor and moving the spindle head 12 toward the workpiece 16, a hole having a required diameter is formed in the workpiece 16. I can open it. At this time, the holding piece 40 moves under the urging of the hydraulic cylinder 32 so that the periphery of the processing portion of the workpiece 16 bends inward by the axial thrust of the drill 22, so that the workpiece 16 is always moved to the workpiece 16. Be abutted. Thus, the holding piece 40 can prevent the processing portion bent with the progress of the drill 22 from springback after drilling and penetration.
2 can be prevented.

After the completion of the drilling, the spindle head 1
When the workpiece 2 is moved backward, the processing portion can be prevented from bending outward by the holding piece 40, so that the drill 22 can be smoothly pulled out from the workpiece 16. Then, by urging the hydraulic cylinder 32 in the reverse direction, the moving member 28 moves backward with respect to the support member 24 while the lever 38 faces the operating position. In this state, the holding frame 14 is moved in the XY directions, and the workpiece 1 is moved.
After adjusting the position of the drill 22 with respect to 6, the hydraulic cylinder 32 is urged in the forward direction to
The hole can be made at a new position by contacting the workpiece 16 with the workpiece 16 and moving the spindle head 12 forward.

Next, when replacing the drill 22 with a face mill, for example, the spindle head 12 is retracted to the initial standby position, and the hydraulic cylinder 32 is urged in the reverse direction to move the moving member 28 to the supporting member 24. To move backward. The second elongated hole 28b
The regulating pin 52 that has been in contact with the rear end of the support member 24
Abuts against the rear end of the concave groove 24b of the moving body 46.
And the retraction of the rod 42 is prevented (see FIG. 5). On the other hand, since the moving member 28 continues to retreat, the pinion portion 34a of the support shaft 34 with respect to the rack portion 42a.
The support shaft 34 and the lever 38 rotate counterclockwise under the meshing action of the two, and the lever 38 returns to the standby position where the lever 38 is retracted from the front surface of the main shaft 20. That is, the lever 38 can be retracted from the front surface of the spindle 20 which may interfere with the automatic tool changer, and the operation of changing the drill 22 to the face mill by the automatic tool changer can be performed without any trouble. The lever 38 is in the operating position.
After retreating integrally with the moving member 28 to a predetermined position
At the standby position, the workpiece 16
There is no risk of interference.

In the embodiment, the actuator of the moving member is used .
Although a hydraulic cylinder has been described as an example, the present invention is not limited to this, and cylinders and motors using other fluids can be used as appropriate as long as they can move the moving member linearly. It is.

[0022]

As described above, according to the apparatus for holding a workpiece of a machine tool according to the present invention, a holding member which can be brought into contact with a part close to a processing part of a workpiece with which a tool contacts in machining. Can be retracted from the front surface of the spindle. Therefore, there is no interference between the automatic tool changer and the holding member at the time of tool change, and automatic tool change can be performed without any trouble. Further, when drilling with a tool, springback of the processed portion after drilling and penetration is prevented, so that breakage of the tool can be prevented. Further, the processed tool can be smoothly pulled out of the workpiece. Furthermore, since the structure is simple, there are advantages that the manufacturing cost can be reduced. In addition,
With the holding member facing the operating position, move it integrally with the moving member.
By providing a moving area, the holding member can be
It can abut in parallel and interferes with the workpiece
It can be moved to the standby position without causing it to move.

[Brief description of the drawings]

FIG. 1 is a side view of a main part of a machine tool according to an embodiment of the present invention, partially cut away.

FIG. 2 is a front view of a main part of the machine tool according to the embodiment.

FIG. 3 is a vertical sectional side view showing a main part of the holding device according to the embodiment in a state where a lever is positioned at a standby position.

FIG. 4 is a vertical sectional front view of a main part of the holding device.

FIG. 5 is a vertical sectional side view of a main part showing a state where a lever of the holding device according to the embodiment is positioned at an operating position.

FIG. 6 is a longitudinal sectional side view showing a main part of the holding device of the embodiment in a state in which the holding piece is in contact with a workpiece.

[Explanation of symbols]

 12 Spindle head 16 Workpiece 18 Saddle 20 Spindle 22 Tool 24 Support member 24b Groove 28 Moving member 28aFirstLong hole 28b2nd slot  32 Hydraulic cylinder (actuator) 34 Support shaft 34a Pinion 38 Lever 42 Rod(Actuator
Material) 42a Rack 46 Moving body(Actuator
Material) 50 compression spring(Elastic member) 52 Regulatory pin

Claims (2)

(57) [Scope of request for utility model registration] A tool (22) having a spindle (20) rotatably provided on a spindle head (12) slidably disposed on a saddle (18), and detachably provided at one end of the spindle (20). By the work (16)
In a machine tool that performs required processing, the support member (24) provided on the saddle (18) is slidably disposed, and driven by an actuator (32) disposed on the saddle (18), wherein through the moving member which is parallel to forward and backward movement with the axis of the spindle (20) to the workpiece (16) (28), the axis (34) intersecting the moving direction of the moving member (28)
Is rotatably pivoted to said movable member (28), the spindle (20)
Operating position facing the front and standby to retract from the front of the spindle (20)
A holding member (38) movable between the position and the position; and a moving member (28) disposed on the moving member (28) for moving the moving member (28) forward.
With the movement , the holding member (38) facing the standby position is moved to the operating position.
After moving the holding member (38) to the operating position
While moving forward with the moving member (28)
As the moving member (28) retreats, the
With the holding member (38) facing the operating position and the moving member (28)
Workpieces for machine tools characterized by comprising an operating mechanism (24b, 28b, 34a, 42, 42a, 46, 50, 52) for integrally moving back to a standby position after a required length of movement Holding device. The operating mechanism is slidably disposed in a first elongated hole (28a) formed along a longitudinal direction of the moving member (28), and is formed on the shaft (34). Operating members (42, 46) in which a rack portion (42a) meshing with the pinion portion (34a) is formed, and the moving member (28) is drilled to communicate with the first elongated hole (28a), this first second <br/> slot extending parallel to the long hole (28a) (28b), projecting from the said actuating member (42,46), said second elongated hole (28b )
Groove (24b) formed inside the support member (24) protruding from
And a regulating pin (52) slidably facing the movable member (28). The regulating pin (52) is disposed in the first elongated hole (28a) of the moving member (28) . groove in the rear end of (24b) becomes from an elastic member for urging the abutting direction (50), upon forward and backward movement of the movable member (28), the regulating pin (52)
When the rear end of the second elongated hole (28b) is not in contact with the rack member (42a), the moving member (28) and the operating member (42, 46) relatively move. The holding member (38) moves between the standby position and the operating position under the action of meshing with the pinion portion (34a), and the rear end of the second elongated hole (28b) is connected to the regulating pin (52). 2. The workpiece holding device for a machine tool according to claim 1, wherein the contact member is configured to move integrally with the moving member in a state where the operating member faces the operating position.