JP2534937B2 - 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 work piece holding device for a machine tool, and more particularly to a work piece holding apparatus for machining a work piece having a thin plate thickness. The present invention relates to a device for holding a workpiece, which can prevent vibration of a part due to cutting resistance of a tool and the like and can achieve good and reliable machining.

[0002]

2. Description of the Related Art A flat surface, curved surface, groove,
A milling machine is generally known as a machine tool for machining screws, gears and the like. This milling machine is configured such that a spindle head provided on a column is rotatably provided with a spindle, and a required work is performed on a workpiece by a tool detachably attached to the tip of the spindle. That is,
Positioning and fixing the workpiece on the table of the milling machine, along the machining surface of this workpiece, move the tool such as the face milling machine (milling cutter) attached to the milling machine, or move the table to the tool The required processing is performed on the workpiece by moving the workpiece.

[0003]

As described above, in the milling machine, machining is performed by forcibly pressing and moving the rotating tool against the workpiece. Therefore, the cutting resistance of the tool is inevitably applied to the work piece during the machining by the tool. In this case, for example, when the above-described processing is performed on the open end surface of a work piece such as a box frame, if the plate thickness of the frame is sufficient, there is almost no problem even if cutting resistance is added. . However, when the plate thickness is thin, there are drawbacks such that the periphery of the processed portion of the work piece vibrates due to the strong cutting resistance of the tool, machining becomes impossible, and a smooth cutting surface cannot be obtained.

[0004]

SUMMARY OF THE INVENTION The present invention has been proposed in view of various drawbacks inherent in machining an open end surface of a thin plate to be machined, such as the above-mentioned box frame, in order to solve the problems. Even if a cutting resistance due to a tool is applied to the work piece during the machining, a means for preventing the work piece from vibrating for reliable machining and obtaining a smooth finished surface is provided. The purpose is to provide.

[0005]

[Means for Solving the Problems] Overcoming the above-mentioned drawbacks,
In order to achieve the intended purpose, the present invention provides a spindle head that is rotatably provided with a spindle, and a tool that is detachably attached to one end of the spindle to perform a required machining on an end surface of a workpiece. In the machine, sandwich the spindle of the spindle head
It is rotatably supported on both sides and extends parallel to the main axis.
A pair of support shafts are arranged so as to rotate integrally with the support shafts.
Installed in the vicinity of the part to be machined by the tool.
A pair of roller support arms facing each other so that
Identical to the end of each roller support arm
Support plate that can rotate in the direction and each roller support arm
Support of the other roller support arm on the pivoted support plate
The work piece is rotatably supported on the side facing the holding plate,
A plurality of rollers that can come into contact with each other, and the respective roller support arms
And a supporting plate, and the supporting plate is always attached to
On the side of the roller support arm that points the workpiece.
The tension spring that urges the rotation toward the main shaft head
Is installed and connected to each support shaft to rotate the support shaft in the forward and reverse directions.
It consists of a pair of moving cylinders and urges the cylinders.
The support plates so that the support plates move toward each other.
By rotating the arm, the applied
It is characterized in that the work is sandwiched between the plurality of rollers .

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A workpiece holding device for a machine tool according to the present invention will be described below with reference to the accompanying drawings with reference to preferred embodiments.

[0007] Figure 1 is a perspective view schematically showing a principal part of the milling machine in accordance with a preferred real施例of the present invention, FIG. 2 is a schematic side view showing an overall configuration of a milling machine.

In the illustrated milling machine 10, a saddle 65 is slidably mounted on a bed 12 having a T-shaped cross section, and the saddle 65 includes, for example, a combination of a ball screw and a nut, or a rack and a pinion. By a suitable feeding mechanism (not shown) consisting of a combination, etc., the longitudinal direction of the bed 12
It is reciprocated in the (Y direction) (see FIG. 3 ). A guide surface 65a is formed on the upper surface of the saddle 65, and a holding base 67 having a base 66 on the front side is slidably mounted on the guide surface 65a. The holding base 67 is similar to the feeding mechanism of the saddle 65. It is configured to be reciprocated in the X direction along the guide surface 65a by such a mechanism. In addition, in the position adjacent to the bed 12,
A table capable of correspondingly positioning the workpiece 28 in front of the first spindle 24 and below the second spindle 82 described later.
(Not shown) is installed.

(Regarding Base Body) As shown in FIG. 4 , the base body 66 has a main body 66a fixed to a holding base 67, and a front side (a side away from the holding base 67) at both ends in the Y direction of the main body 66a. A pair of protruding arms 6
It is formed in a U shape from 6b and 66b. Both arms 6
Swing shafts 68, 68 extending in the Y direction are rotatably supported near the tips of the arms 6b, 66b.
6b is projected to the inside (the side toward the facing arm 66b) and the outside.

(Oscillating Body) Between the two arm portions 66b, 66b of the base 66, there is seen an oscillating body 69 formed in a U-shape in plan view, and each arm portion of the oscillating body 69 protruding from the main body 69a. 69b and 69b are
The swing shafts 68 protruding inward from the corresponding arm portions 66b of the base 66 are fixed to the swing shafts 68, respectively. In addition, the arm portion 6 of the swing shaft 68
As shown in FIG. 1 , one end of a swing arm 70 is fixed to the shaft end protruding outward from 6b, and a sector gear 71 is arranged at the other end extending rearward of the swing arm 70. .

As shown in FIG. 4 , a drive shaft 72 extending parallel to the Y direction is rotatably supported by the main body 66a of the base body 66, and the drive shaft 72 projects outward from the main body 66a of the drive shaft 72. Gears 73, 73 are arranged at the shaft ends, and each gear 73 is configured to mesh with a corresponding sector gear 71. In addition, another gear 7 is provided at a position where the drive shaft 72 faces the main body.
4 is provided, and the gear 74 is the gear 7 connected to the output shaft of the swinging motor 75 provided on the base 66 via a speed reducer.
It meshes with 6. Therefore, by driving the swinging motor 75 in the forward and reverse directions, the drive shaft 72, the swinging arm 70,
The oscillating body 69 oscillates in the vertical direction via 70 and the oscillating shafts 68, 68 (see FIGS. 13 and 14 ).

(Spindle Head) As shown in FIG. 4 , the inner surface of the main body 69a of the swinging body 69 (the surface of the base 66 which is separated from the main body 66a) is Y-shaped.
A pair of guide rails 77, 77 spaced apart by a predetermined distance in the direction
Are arranged in parallel, and the spindle head 22 is arranged on both guide rails 77, 77 so as not to fall off and to be able to move up and down (reciprocally movable in the Z direction). In addition, both guide rails 7 of the swinging body 69
The detaching direction center position of 7,77, as shown in FIG. 1 0,
A ball screw 78 is rotatably arranged in parallel with the guide rail 77, and the upper end of the ball screw 78 has an oscillating body 69.
It is connected to the output shaft of a lifting motor 80, which is arranged upside down via a bracket 79 on the upper surface of the. Further, the ball screw 78 has a nut 81 arranged on the back surface of the spindle head 22.
Is screwed into. Therefore, the ball screw 78 and the nut 81 are driven by driving the lifting motor 80 in the forward and reverse directions.
In cooperation with the main spindle head 22,
Lifting moving along the 7,77 (see Fig. 1 2).

[0013] Here, the spindle head 22 shown in real施例is
As shown in FIG. 2 , a tool provided with the first main spindle 24 and the second main spindle 82 orthogonal to the XZ direction and arranged on the first main spindle 24.
(Face milling) 26 is used to process the end surface of the work piece 28.
(FIGS. 11 and 12 ), and a tool (drill) 83 provided on the second spindle 82 is used to perforate the workpiece 28 (FIGS. 15 and 16 ). In addition, each spindle 2
When the work piece 28 is machined by the tools 26, 83 arranged on the No. 4, 82, respectively, the devices for holding the machined parts of the work piece 28 are provided correspondingly.
The configuration of members related to No. 4 will be described, and then the configuration of members related to the second main shaft 82 will be described.

(Regarding the First Spindle) As shown in FIG. 5 , the spindle head 22 includes a first spindle 24 extending in the X direction so as to be rotatable.
A tool 26 such as a face milling cutter is detachably attached to an end portion protruding from the front surface of the spindle head so as to direct an end surface 28a of a workpiece 28 positioned on the table. Further, a first motor 30 is arranged inside the spindle head 22, and the first motor 30 drives the first spindle 24.
Is driven to rotate. Therefore, by moving the spindle head 22 up and down with the rotating face mill 26 in contact with the end surface 28a of the workpiece 28, the end surface 28a
There is processed (see Fig. 1 2).

[0015] Above the (first the holding device of the workpiece associated with the main axis) arrangement position of the first spindle 24 in the spindle head 22, as shown in FIGS. 5 and 7, given in the Y-direction interval A pair of support shafts 84 spaced apart and parallel to the first main shaft 24,
84 is rotatably supported. Tip of each support shaft 84
A sleeve 85 is externally fitted inward of a predetermined length from (the end portion projecting from the front surface of the spindle head 22) so as to be rotatable integrally with the support shaft 84 and movable in the axial direction. A peripheral groove 85a is formed near the rear end of the sleeve 85.
Further, a cylinder 86 is arranged between the support shafts 84, 84, and an engagement member 87 arranged at the tip of a piston rod 86 a of the cylinder 86 is provided with a circumferential groove 8 of the sleeves 85, 85.
5a and 85a are commonly fitted. Therefore, by urging the cylinder 86 in the forward and reverse directions, the pair of sleeves 85, 85 moves back and forth in the X direction along the support shafts 84, 84 (see FIG. 8 ). The engagement member 87 is the sleeve 8
The sleeves 85 and 85 are allowed to rotate because they are only loosely fitted to the sleeves 5 and 85.

[0016] The sleeve 85, as shown in FIG. 6,
A roller support arm 88 having a dogleg shape is integrally formed, and both roller support arms 88, 88 are opposed to each other with the front milling cutter 26 interposed therebetween. At the lower end of the roller support arm 88, a pair of support plates 8 having a substantially triangular shape is provided.
9, 89 are rotatably supported by a pin 90 parallel to the first main shaft 24. And the supporting plates 89, 8
A plurality of (two in the embodiment) rollers 50 are rotatably sandwiched at a portion of the roller 9 that faces the other roller supporting arm 88 facing each other. The peripheral surface of each roller 50 is positioned so as to project outward from the support plate 89,
The peripheral surface of the roller 50 can be brought into contact with the workpiece 28. Further, the stretched tension spring 91 between the upper end and the roller support arm 88 of the support plate 89, the support plate 89 is low
La 50 directs the workpiece 28 of the roller support arm 88
It is always urged to rotate toward the side .

On the top plate of the spindle head 22, as shown in FIG. 1 , a pair of hydraulic cylinders 64, 64, which are swingably supported in the vertical direction, are arranged in parallel at predetermined intervals in the X direction. The cylinders 64, 64 are positioned so that their head sides face each other. Further, as shown in FIG. 8 , the other end of the rotary arm 92, which has one end integrally rotatable with the support shaft 84 and is slidable in the axial direction, is
It projects upward through a long hole 22a formed in the top plate of the spindle head 22. The piston rod 64a of the corresponding cylinder 64 is clevis-connected to the protruding end of the rotating arm 92. Therefore, the cylinder 6
By urging 4 in the forward and reverse directions, the support shaft 84 rotates in the forward and reverse directions, whereby the roller support arm 88 swings within a predetermined range. That is, the pair of cylinders 6
By urging the rollers 4, 64 in opposite directions, the rollers 50, 50 arranged on the roller supporting arms 88, 88
The work piece 28 can be clamped or released.
(See Figure 6 ).

It should be noted that while the cylinder 64 is processing the workpiece 28 by the face mill 26, the roller 50
Is set to urge the work piece 28 in a direction in which the work piece 28 is pressed against the workpiece 28 at a predetermined pressure. Therefore, even if the work piece 28 is distorted or bent, the roller 50 follows the work piece 28 without moving away from the work piece 28.

(Regarding the Second Spindle) As shown in FIG. 9 , the spindle head 22 rotatably includes a second spindle 82 extending in the Z direction.
Of the tool such as a drill on the end protruding from the bottom surface of the holder of
Is detachably attached so that the workpiece 28 positioned on the table can be perforated. A second motor 93 is arranged upside down on the ceiling surface of the main spindle head 22, the motor 93 is connected to a second main spindle 82 via a coupling (not shown), and the second main spindle 82 is rotated by the second motor 93. Driven. Therefore, by lowering the spindle head 22 with the rotating drill 83 facing above the work piece 28, a hole having a required diameter can be formed in the work piece 28 (see FIG. 15 ).

[0020] On both sides (the second for holding apparatus of a workpiece associated with the main axis) sandwiching the elevating motor 80 of the bracket 79 which is disposed on the upper surface of the oscillator 69, as shown in FIG. 1 0, the pair The cylinders 94, 94 are arranged upside down. Further, on the front surface (the surface facing the spindle head 22) of the main body 69a of the oscillating body 69, a pair of guides 9 are vertically spaced apart from each other by a predetermined distance in a position directly below each cylinder 94.
5,95 are projected, and slide rods 9 are attached to both guides 95.
6 are slidably disposed. The upper end of each slide rod 96 is connected to the corresponding cylinder 94, and the slide rod 96 is moved up and down along the guides 95, 95 by the forward and reverse biasing of the cylinder 94.

As shown in FIG. 9 , a bracket 97 extending forward is horizontally arranged at the lower end of the slide rod 96, and an electromagnet 98 is arranged on the lower surface of the extending end of the bracket 97. Further, as shown in FIG. 3 , the pair of electromagnets 98, 98 arranged at the lower ends of the rods 96, 96 are positioned so as to face both sides of the axis of the second spindle 82 arranged in the spindle head 22. There is. That is, the electromagnet 98
Is a drill 8 arranged on the second spindle 82 by electromagnetically adsorbing the vicinity of the processing site of the workpiece 28 positioned on the table.
It functions to prevent the work piece 28 from vibrating or bending during the drilling process by 3.

[0022]

[Operation of Embodiment] Next, actually sticks to the description of the use of milling machine according to actual施例.

(Regarding Machining by Front Milling Machine Arranged on First Spindle) First, with the open end face 28a of the workpiece 28 facing the front milling cutter 26 mounted on the first spindle 24, the table ( Positioning and fixing to (not shown). The time base 66, as shown in FIG. 1 1, the workpiece 28
The roller support arms 88, 88 stand by at a position separated from the front side of the front milling cutter 26 with the roller support arms 88, 88 opened (a state shown by a chain double-dashed line in FIG. 8 ).

When processing the end surface of the workpiece 28, first, the cylinder 86 is urged in the direction in which the piston rod 86a extends from the inside of the barrel, whereby the engaging member 87 is formed.
Support sleeves 84,8
Move forward along 4. This allows the sleeve 8
Roller support arms 88,8 formed integrally with the 5,85
8 projects to the front side of the front milling cutter 26 in the open state (state shown by a solid line in FIG. 8 ). Next, the first motor 30 is driven to rotate the front milling cutter 26 attached to the tip of the first spindle 24, and the base 66 is moved in the X direction along the guide surface 65a of the saddle 65. as shown in 1 2 is brought into contact with a required depth of cut of the face milling cutter 26 to the end surface 28a of the workpiece 28. At this time, the work piece 28 faces between the roller support arms 88, 88 in an open state.

Further, by urging the hydraulic cylinders 64, 64 disposed on the ceiling surface of the spindle head 22 in a required direction (in the embodiment, the direction in which the piston rod 64a is pulled into the barrel), the rotating arm 92 is moved. The support shafts 84, 84 rotate in opposite directions via the shafts 92, 92. Since the sleeve 85 is externally fitted so as to rotate integrally with the support shaft 84, the pair of roller support arms 88, 88 are provided.
Is rotated in a direction in which rollers 50, 50 rotatably supported at their lower ends via support plates 89, 89 are pressed against the side surface of the workpiece 28. As a result, the portion of the workpiece 28 close to the machined portion of the front milling cutter 26 is the roller 5
It can be effectively prevented from being vibrated by the cutting force of the front milling cutter 26 because it is sandwiched by 0, 50.

Next, the elevating motor 80 is driven in a predetermined direction to elevate the spindle head 22 with respect to the oscillating body 69, whereby the end surface 28a of the workpiece 28 is machined along its longitudinal direction. It In addition, the opposing rollers 50, 5
0 rotates while the work piece 28 is clamped as the spindle head 22 moves.

Since the hydraulic cylinder 64 urges the roller 50 disposed on the corresponding roller support arm 88 to press the work piece 28 with a required pressure, the work piece 28 is not distorted or bent. Even if there is, the rollers 50, 50 move following the distortion or bending, and always clamp the workpiece 28 at a required pressure. Therefore, the end surface 28 of the workpiece 28
With a, a smooth cutting surface can be obtained over its entire length.

[0028] In the milling 10 of the real施例, since the spindle head 22 are swingably configured vertically,
As shown in FIGS. 13 and 14 , the open end surface 2 of the workpiece 28
Even if 8a is inclined, the end face of the end face 28a can be processed.

That is, the workpiece 28 is positioned so that its inclined open end surface 28a faces the front surface of the front milling cutter 26. Next, the swinging motor 75 disposed on the base 66 is driven in a desired direction to swing the swinging body 69 with respect to the base 66, and the front surface of the spindle head 22 disposed on the swinging body 69 is processed. 28 inclined end surface 28a
Parallel to.

In this state, the front milling cutter 26, which moves the base 66 forward to rotate and drive, is pressed against the end face 28a, and the workpiece 28 is held by the rollers 50, 50 of the pair of roller supporting arms 88, 88. Let Then
The spindle head 22 is moved up and down with respect to the rocking body 69, and the base 66 is moved forward and backward with respect to the workpiece 28, thereby processing the inclined open end surface 28a of the workpiece 28 along the longitudinal direction thereof. can do.

(Regarding processing by a drill arranged on the second spindle) Next, a practical example of drilling the workpiece 28 by the drill 83 of the second spindle 82 arranged on the spindle head 22 will be described. explain. First, the workpiece 28 is positioned and fixed to the table (not shown) with the upper surface level thereof being lower than the lower surface level of the base 66. At this time, the base 66 stands by at a position separated from the workpiece 28, and the spindle head 22 faces the uppermost position with respect to the rocking body 69. Further, the electromagnet 98 arranged at the lower end of the slide rod 96 stands by in a state where the piston rod of the cylinder 94 is pulled into the barrel.

When drilling the workpiece 28,
First, the base body 66 is moved forward toward the workpiece 28, and the second spindle 82 disposed on the spindle head 22 is positioned above the drilled portion of the workpiece 28. Next, as shown in FIG. 16 , the pair of cylinders 94, 94
Is synchronously urged in the direction in which the piston rod extends from the barrel, and the slide rods 96, 96 are lowered so that the electromagnets 98, 98 are magnetically attracted to the workpiece 28. Further, the cylinder 94 is stopped and controlled at a position where the electromagnet 98 is magnetically attracted to the workpiece 28, and the electromagnet 98 is positioned at a fixed position so as not to move. As a result, the processed surface of the work piece 28 is stably held.

Next, the second motor 93 rotates the drill 83 attached to the tip of the second main shaft 82, and
Driving the elevating motor 80, if lowering the spindle head 22 with respect to the oscillator 69, as shown in FIG. 1 5,
A hole having a required diameter can be formed in the upper surface of the work piece 28. At this time, since the portion close to the drilled portion is firmly held by the electromagnets 98, 98, it is possible to reliably prevent the machined surface from vibrating or bending as the drill 83 advances. Accurate and reliable drilling can be achieved.

When the holed portion of the workpiece 28 is tilted, the rocking body 69 is rocked with respect to the base 66 so that the tilted surface and the bottom surface of the spindle head 22 are parallel to each other. Only then, the inclined surface can be subjected to accurate and reliable drilling.

[0035]

As described above, according to the workpiece holding apparatus for a machine tool of the present invention, a portion close to the processed portion of the workpiece which the tool contacts during machining is attached to the spindle.
A pair of roller support arms rotatably mounted on the
Are configured to sandwich the supporting the roller. Therefore, even if a cutting resistance is applied to the workpiece through the tool, the machining surface can be effectively prevented from vibrating. That is,
Even if the work piece is formed of a thin plate, it is possible to perform the work reliably and obtain a smooth cutting surface. Further, since the structure is simple, there is an advantage that the manufacturing cost can be kept low.

[Brief description of drawings]

1 is a schematic perspective view showing the main part of the milling machine in accordance with the actual施例of the present invention.

2 is a schematic side view showing an overall configuration of a milling machine according to actual施例.

3 is a front view of the milling machine shown in FIG.

FIG. 4 is a plan view showing a cross section of a main part of the milling machine shown in FIG. 1 .

FIG. 5 is a schematic perspective view of an essential part showing a moving mechanism of a roller support arm.

FIG. 6 is a front view of relevant parts showing the relationship between the front milling cutter and the roller support arm.

FIG. 7 is a cross-sectional plan view of essential parts showing a moving mechanism of a roller support arm.

FIG. 8 is a vertical cross-sectional side view of essential parts showing a moving mechanism of a roller support arm.

9 is a side view showing the longitudinal part of the milling machine in accordance with the actual施例.

FIG. 10 is a front view showing a part of the rocking body in a vertical section.

[11] The face mill milling machine according to actual施例a partially cutaway side view showing a state before processing the end face of the workpiece.

[12] the face mill milling machine according to actual施例a partially cutaway side view showing a state of processing the end face of the workpiece.

[13] the face mill milling machine according to actual施例is a side view showing a state of processing the inclined end face of the workpiece.

[14] the face mill milling machine according to actual施例is a side view showing a state of processing the inclined end face of the workpiece.

The milling drill according to Figure 15 the real施例a partially cutaway side view showing a state before being subjected to drilling in the workpiece.

By milling drill according to [16] real施例,
It is a partially cutaway side view showing a state in which a drilling process is performed on a workpiece.

[Explanation of symbols]

 22 Spindle head 24 Spindle 26 Face mill(tool) 28 Workpiece 28a End face 50 Roller 64 Hydraulic cylinder 84 Support shaft85 Sleeve 86 cylinders  88 Roller support arm89 Support plate 91 Tension spring

Claims (2)

(57) [Claims] 1. A tool (26) provided on a spindle head (22) rotatably with a spindle (24) and detachably provided at one end of the spindle (24).
Thus, in a machine tool in which the end surface (28a) of the work piece (28) is subjected to required machining, the main shaft head (22) is rotatable about both sides of the main shaft (24).
A pair of support shafts that are pivotally supported and extend parallel to the main shaft (24).
(84, 84), and the support shaft (84, 84) is arranged so as to rotate integrally with,
The vicinity of the processed part of the workpiece (28) by the tool (26) is pinched.
A pair of roller support arms (88, 88) facing each other so that they can be seen.
And each of the roller support arms (88) is pivotally supported on the end of the arm.
The support plate (89) rotatable in the same direction as the frame (88) and the support plate (89) pivotally supported by the roller support arms (88).
Facing the support plate (89) of the other roller support arm (88)
Is rotatably supported on the side where it touches the workpiece (28).
A plurality of possible rollers (50) and tension between each roller support arm (88) and support plate (89).
The support plate (89) is always supported by the roller (50).
Aim the side of the holding arm (88) toward the workpiece (28).
And a tension spring (91) that urges it to rotate, and is attached to the spindle head (22) and connected to each support shaft (84).
Pair of cylinders that rotate the support shaft (84) in the forward and reverse directions.
(64, 64) and biases the cylinders (64, 64) to support the support plates (89, 89).
Rotate both roller support arms (88, 88) so that they approach each other
To be processed between the two support plates (89, 89)
A workpiece holding device for a machine tool, wherein the object (28) is sandwiched between the plurality of rollers (50, 50) . 2. The support shafts (84) are integrally rotatable with each other.
And the sleeve (85) is
The roller support arm (88) is fitted into the sleeve (85).
Are arranged so as to rotate integrally, and both support shafts (8
Both sleeves (85, 85) fitted on the outer surface of the spindle head (2, 84)
It is connected to the cylinder (86) arranged in 2) , and the cylinder (86)
Both roller support arms by urging the
(88,88) is designed to move back and forth in the axial direction of the support shaft (84,84).
The workpiece holding device for a machine tool according to claim 1, which is formed.