JPS6355401B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lathe that rotates a workpiece and performs cutting with a cutting tool, and provides a lathe that has particularly high machining accuracy and is suitable for automating loading and unloading of workpieces. .

In recent years, the demand for precision machined parts has increased, and various lathes have been put into practical use to meet this demand.

A conventional cam-type lathe will be explained based on FIGS. 1 and 2.

Chuck 3 attached to spindle 2 of main shaft section 1
The object to be cut 4 is rotated. The cutter 5 is fixed by a cutter holder 6 and a cutter rest 7 to an X slide table 9 that moves in the X direction. X slide table 9 and Y slide table 10 are link 1
It is driven by cams 13 and 14 via cams 1 and 12. The stopper 15 is for determining the position of the Y slide table 10.

Here, the X slide table 9 and the Y slide table 10 have a structure in which a table movable section 16 moves along a slide table 17, as shown in FIG. Since the slide guide 17 and the table movable part 16 need to slide with high precision, generally a sliding piece 18 is provided between the slide guide 17 and the table movable part 16 as shown in FIG. Efforts have been made to apply preload using the screw 19. However, since the movement of the table movable portion 16 depends on the machining accuracy of the slide guide 17, the current situation is that the strokes of the slide tables 9 and 10 cannot be made large. For this reason, the conventional lathe had the disadvantage that the cutter 5 remained close to the workpiece 4 even after the cutting process was completed, making it difficult to automatically load and remove the workpiece.

It is also conceivable to provide another set of slide tables on top of the X slide table 9 to separate the blade from the workpiece after the cutting process, and to fix the blade on top of it, but the number of slide surfaces in the X direction is Increase,
Moreover, since the height of the table becomes high, there arises a problem that the machining accuracy decreases.

The present invention eliminates the above drawbacks, namely:
During cutting, the movement of the blade is controlled by the first drive means to perform accurate machining, and after machining, the slide table is moved back by the second drive means, making it easy to automatically load and unload the workpiece. The present invention will be described in detail below with reference to Examples.

FIG. 3 is a plan view of the lathe provided by the present invention, and also shows the layout of the hydraulic unit and control device as auxiliary equipment. Fig. 4 is a front view of the lathe of the embodiment;
FIG. 5 is a side view.

3 to 5, a chuck 22 is attached to the spindle 21 of the main shaft portion 20, and a workpiece 23 is gripped by the chuck 22. The spindle 21 has a main shaft motor 24 and a coupling 2.
The pulley 28 receives the rotation of a belt pulley 26 connected by a belt 5 through a flat belt 27, and is rotated. Here, the main shaft motor 24 is fixed to the frame 30 by a bracket 29.

On the other hand, the cutter 31 is attached to a slide table section 34 via a cutter holder 32 and a tool rest 33. The slide table section 34 includes an X slide table 35 and a Y slide table 36.

Further, the camshaft motor 37 is attached to the frame 30 via a bracket 38, and the camshaft motor 37
The output is transmitted to the input shaft 43 of the reduction gear 42 via the pulley 39, timing belt 40, and pulley 41. Here, when the input shaft 43 of the reducer 42 rotates, the camshaft 44 which is the output shaft rotates, the X cam 45 and Y cam 46 attached to the camshaft 44 rotate, and the The slide table 35 and Y slide table 36 are driven. Furthermore, an encoder 49 is connected to the camshaft 44, and a pulse signal that detects the rotational position of the camshaft is sent to the control device 50.

In this embodiment, the cam shaft 44 and the X cam 4
5. The lever 47 constitutes the first driving means in the present invention and regulates the movement of the X slide table 35.

In FIG. 3, a hydraulic unit 51, which is a hydraulic pressure generating device, includes a main shaft portion 20, a slide table portion 3,
The control device 50 controls the hydraulic unit 51 and the lathe main body 53 based on signals from the encoder 49.

The configuration of the lathe provided by the present invention has been schematically shown above, and each part will be explained in detail next.

FIG. 6 is a front sectional view of the main shaft portion 20, and the seventh
The figure is a BB' sectional view in FIG. 6.

In FIGS. 6 and 7, the spindle 21 is fitted into the radial thrust pusher 55 and the radial thrust pusher 56, which are press-fitted into the housing 54, with a gap of about 10 μm. A flange 57 for receiving a thrust load is fixed to the spindle 21 with a nut 59 via a collar 58. Radial thrust push 55
A thrust pushbutton 61 is attached at a position sandwiching the flange 57 with a spacer 60 interposed therebetween.
At this time, the flange 57 and the thrust pushbutton 61,
and the gap with the radial thrust pushbutton 55 is
The thickness should be approximately 10μm.

Radial thrust pusher 55 spindle 2
There are 4 pockets 62 in the circumferential direction on the surface that mates with 1.
Pockets 63 are also provided at four locations in the circumferential direction on the surface of the radial pushbutton 56 that engages with the spindle 21. Subscripts a, b, c, d in Figure 7
is used to distinguish individual pockets.
The pockets 62 and 63 have an external hydraulic unit 51.
Hydraulic pressure is supplied from (FIG. 3) through a manifold 64, through first oil passages 65 and 66, and further through shibori 67 and 68.

In addition, pockets 69 and 70 are provided on the surfaces of the radial thrust pushbutton 55 and the thrust pushbutton 61 that face the flange 57, and like the pockets 62, hydraulic pressure is supplied from the first oil passage 65 through the shibori 71. .

From the pockets 62, 63, 69, 70 to the gap between the spindle 21 and the radial pusher 56 and radial thrust pusher 55, or the flange 57
The hydraulic oil flowing out through the gap between the radial thrust pusher 55 and the thrust pusher 61 is collected into the hydraulic unit 51 through the second oil passage 72. In FIG. 6, a part of the second oil pipe 72 is omitted. In FIG. 6, the hydraulic oil that has leaked further outward from the second oil pipe 72 is transferred to the third oil pipe 73 for drain.
The water passes through and is collected by the hydraulic unit 51.

As described above, the spindle 21 is supported by the radial thrust pushers 55, 56, and 61 using a hydrostatic fluid bearing structure.

A bracket 74 is fixed to the radial push 56, and a bearing 75 is attached to the bracket 74 by a collar 76 and a nut 77. The pulley 28 is rotatably attached to the bracket 74 via a bearing 75 by a collar 78 and a holding plate 79. Further, there is a transmission ring 80 between the presser plate 79 and the spindle 21, and the presser plate 79 and the transmission ring 80 are connected by an elastic key 81. Further, the transmission ring 80 and the spindle 21 are connected to the key 82.
are connected.

With the above configuration, when the rotational force is transmitted to the pulley 28 by the flat belt 27 in FIG. 4, the rotational force is transmitted to the spindle 21 by the key 81, the transmission ring 80, and the key 82. At this time, the spindle 21 is supported by a hydrostatic fluid bearing structure, and since an elastic body is used for the key 81, the spindle 21 rotates with less vibration of the axis.

Next, Figure 3, Figure 4, Figure 5, Figure 8, Figure 9
The slide table section 34 will be explained with reference to FIGS. 10, 11, 12, 13, and 14. FIG. 8 is a plan view of the slide table section 34. The cutter 31 is fixed to a tool rest 33 on a Y slide table 36 by a cutting tool holder 32. Furthermore, the Y slide table 36
It is mounted on the slide table 35.

FIG. 9 is a sectional view of COO'C' in FIG. 8, showing the structure of the X slide table 35. In FIG. 9, guide blocks 84 and 85 are fixed to a base plate 83 on the frame 30. As shown in FIG. On the other hand, the top plate 8
6 has center block 87, side block 8
8, 89 are installed, and the guide blocks 84, 8
An X-table movable section 90 that slides along 5 is configured. Top plate 86, side blocks 88, 89 and center block 87, guide blocks 84,
A pocket 91 is provided on the surface facing 85, and a pocket 91 is provided from the external hydraulic unit 51 to the manifold 9.
2. Hydraulic oil is supplied through the first oil passage 93 and through the shibori 94. Further, the hydraulic oil that has leaked out from the pocket 91 passes through a second oil passage 95 for recovering hydraulic oil and is collected by the external hydraulic unit 51.

The hydraulic oil that has flowed further outside from the second oil pipe 95 passes through the third oil pipe 96 and reaches the external hydraulic unit 51.
will be collected.

As described above, the pocket 91, the second oil pipe 95,
The pattern of the third oil pipe 96 is shown in FIG.

In FIG. 10, the shaded area is a raised area and is generally called a land area. A first land portion 97 is provided on the outside of the pocket 91, a second land portion 98 is provided on the outside of the second oil pipe 95, and a third land portion 99 is provided on the outside of the third oil pipe 96. The gaps between the top plate 86, side blocks 88, 89, center block 84, and guide blocks 84, 85 are the lands 9.
7, 98, and 99, it is about 10 μm.

With the above configuration, a hydrostatic fluid bearing structure is formed between the X-table movable section 90 and the guide blocks 84, 85. The sliding portion of the Y slide table 36 has almost the same structure.

FIG. 11 shows the X table 35 in FIG.
DD′ cross-sectional view. An air cylinder 101 is attached to the base block 83 via a block 100. Rod 102 of air cylinder 101
One end is fixed to the center block 87 via a connector 103, a bracket 104 and a block 105. Air is normally supplied to the air cylinder 101 through the air supply port P1106.
The X-table movable section 90 is subjected to a force that causes it to move in the direction opposite to the direction of the arrow X in FIG.

In other words, the air cylinder 101 is
The table movable portion 90 is urged toward the main shaft portion 20, and is constituted by the urging means of the present invention.

A nut 108, into which a stop screw 107 is screwed, is press-fitted into the top plate 86.
09 is installed. There are five stop screws 107 for the X slide table 35. A stopper 110 is attached to the guide block 84. The stopper 110 has five stop pistons 111 corresponding to the five stop screws 107.
There is.

The stop piston 111 has a cylindrical side surface with two opposing flat surfaces, and is housed in the stopper body 112. The stopper 110 has two blocks 113 and 114 for preventing the stop piston 111 from rotating. The stop piston 111 and the blocks 113, 114 have holes 115, 11 larger than the diameter of the stop screw 107.
6,117 are provided. Also stopper 11
0 has air supply ports 118 and 119 on the top and bottom, and when air is supplied to the supply port 118, the stop piston 111 moves down and the stop piston 1
A hole 115 provided in 11 is a stop screw 107.
come to the position. In this state, the X table movable part 90
moves in the direction opposite to the direction of arrow X, even if the stop screw 107 reaches the position of the stop piston 111
Since the stop screw enters the hole 115, it does not have a positioning function. However, the air supply port 11
9, the stop piston 111 rises and the hole 115 of the stop piston 111 does not match the position of the stop screw 107, so the stop screw 107 hits the stop piston 111 and the
The table movable part 90 is positioned.

The top plate 86 is provided with a block 121 on which the tip roller 120 of the lever 47 comes into contact.
is moved.

FIG. 12 shows the FF' cross section of FIG. 11, showing the stop piston 111, the stopper body 112, and the block 1.
13 and 114.

While the X table movable part 90 is moved by the lever 47, the air cylinder 101 is connected to the supply port P.
1106 side, but if air is supplied to the supply port P2122 of the air cylinder 101, regardless of the movement of the lever 47, the X table movable part 90 will be moved in the X direction, that is, the main axis, as shown in FIG. It can be moved back in a direction away from the section 20. Therefore, the movement of the slide table section 34 during turning is performed by the lever 47, and the X-table movable section 90 can be moved backward by the air cylinder 101 after the turning process is completed. This allows the cutter to separate from the workpiece after processing, making it easier to load and remove the workpiece. That is, air cylinder 1
01 constitutes a second driving means for driving the X-table movable section 90 in the present invention in a direction away from the main shaft section 20 in this state, and is a part of the first driving means of the X-table movable section 90. It moves away from the lever 47 to form a space for loading and unloading the workpiece.

FIG. 14 shows the structure of the Y slide table 36 in section EE' of FIG.

A guide block 1 is attached to the base plate 123 attached to the top plate 86 of the X slide table 35.
24 is installed. On the other hand, a center block 127 and side blocks 128 are attached to a top plate 126 constituting the Y table movable section 125.
A plate 129 is fixed to the side block 128, and a hole 13 is formed in the guide block 124.
0, and a compression spring 131 is installed between the plate 129 and the guide block 124. Guide bar 158 is a guide for compression spring 131. Due to this compression spring 131, the Y table movable portion 125 is constantly subjected to a force that moves it in the direction opposite to the direction of the arrow Y in FIG. Also, the top plate 1
A block 133 is attached to the lever 26 at a position where the tip roller 132 of the lever 48 comes into contact. The stopper 134, stopper plate 135, and stop screw 136 function in the same manner as in the case of the X slide table 35.

In this embodiment, the stroke of the X table movable section 90 is large and the stroke of the Y table movable section 125 is small, so the X slide table 35 is equipped with an air spring using an air cylinder 101, and the Y slide table 36 is equipped with a compression spring 131. However, if necessary, the compression spring of the Y slide table 36 can be replaced with an air spring.

Next, the cam drive section shown in FIG. 15 will be explained. FIG. 15 is a sectional view of GOO'G' in FIG. 3.
A lever 47 that acts on the X slide table 35 and a lever 48 that acts on the Y slide table 36.
is rotatably fitted to a lever shaft 137, and the lever shaft 137 is attached to the frame 30 by a bracket 138. Rollers 120 and 132 are rotatably attached to the tips of the levers 47 and 48 by pins 139. One end of the lever 47 contacts the X slide table 35, and the other end contacts the X cam 45.
comes into contact with. Similarly, one end of the lever 48 contacts the Y slide table 36, and the other end contacts the Y cam 46. X cam 45 and Y cam 46 are connected to pin 140,
141 to a transmission collar 142, and the transmission collar 142 is connected to a camshaft 44 by a key 143a. The camshaft 44 is attached to a bearing holder 143 attached to the frame 30 via bearings 144 and 145. The retainer ring 146, spacers 147, 148, and nut 149 hold the bearings 144, 145 on the camshaft 4.
4 and the bearing holder 143. The worm 1 is further attached to the camshaft 44 by a key 150, a spacer 151, and a nut 152.
A wheel 154 is attached which meshes with 53.

The bearing holder 143 has the reducer case 1
55, an encoder 49 is attached via brackets 156 and 157, and this encoder 49 is connected to the camshaft 44 by a connector 159. As a result, the rotational position of the camshaft 44 is determined by the encoder 49.
Detected by Note that the bearing 160 is for suppressing vibration of the tip of the camshaft 44.

The shaft of the worm 153 in FIG. 15 is the input shaft 43 shown in FIG. 5, and receives the rotational force of the camshaft motor 37. Now, when the camshaft motor 37 is rotated, the rotational force is applied to the pulley 39 and the timing belt 4.
0 is transmitted to the input shaft 43 via the pulley 41.
As a result, the worm 153 rotates, and the wheel 1
54, cam shaft 44, X cam 45, Y cam 4
6 rotates. At this time, the X slide table 35
The Y slide table 36 is driven by levers 47 and 48 via rollers 120 and 132 that contact the X cam 45 and Y cam 46. Further, the rotational position of the camshaft 44 is detected by an encoder 49.

Next, the hydraulic circuit of the hydraulic unit 51 that supplies hydraulic oil to the hydrostatic fluid bearings of the main shaft portion 20 and the slide portion 34 will be explained with reference to FIG.

Hydraulic oil sucked up from a tank 163 by a pump 162 driven by a motor 161 passes through a filter 164 and is pressurized by the pump 162 .

The relief valve 165 is for keeping the pressure constant, and the pressure is displayed by a meter 166. The hydraulic pressure output from the pump 162 is transferred to the switching valve 167,
168 , one side is supplied to the main shaft section 20 and the other side is supplied to the slide table section 34 .

The hydraulic pressure coming out of the switching valve 167 passes through the valves 67, 68, and 71 shown in FIG.
3,69,70. Spindle 21, flange 57 and radial thrust pusher 5
5, the pockets 62, 63, 6 through the gap between the radial pushbutton 56 and the thrust pushbutton 61.
The hydraulic oil flowing out from the oil pipes 9 and 70 passes through the second oil pipe 72 and is collected into the tank 163. The hydraulic oil that has leaked further outside the second oil pipe 72 is collected into the tank 163 through the third oil pipe 73.

On the other hand, the hydraulic pressure coming out of the switching valve 168 is supplied to the pocket 91 through the first oil passage 93 and through the shibori 94, as shown in FIG. Most of the hydraulic oil flowing out of the pocket 91 is recovered by the second oil pipe 95. The hydraulic oil further flowing out from the second oil pipe 95 is recovered by the third oil pipe 96. At this time, a pump 170 driven by a motor 169 is connected to the third oil pipe 96 , and the hydraulic oil in the third oil pipe 96 is forcibly sucked by the pump 170 and collected into the tank 163 .

Generally, a sliding mechanism with a hydrostatic fluid bearing structure has the disadvantage that hydraulic oil tends to leak to the outside of the device, and to prevent this, the device becomes large in size. By providing the pump 170, hydraulic oil will not leak to the outside of the device, and the slide table portion can also be designed compactly.

Since the lathe of this embodiment has the configuration described above, it has the following features.

(1) When cutting the workpiece 23 that is rotated by the main shaft section 20, the slide table section 34 to which the cutter is attached has the cams 45, 46, the lever 47,
48. To cut a cylindrical surface, the Y table movable part 125 is
6 and the stopper 134, and the X table movable part 90 moves along the cam 45 and
Driven by. At this time, the X-table movable section 90 moves along the guide blocks 84 and 85. For cutting the end face, the X-table movable section 90 is positioned by the stop screw 107 and the stopper 110, and the Y-table movable section 125 is driven by the lever 48 along the cam 46.
When cutting is finished, the supply port P of the cylinder 101
Air is supplied to 2122, and as shown in FIG.
4, 85 along with the tool rest 33,
The cutter 31 is separated from the main shaft portion 20. This makes it easier to take out the workpiece 23. This is especially effective when automatic extraction is performed.

Furthermore, since the X-table movable section 90 moves on the same guide blocks 84 and 85 both during cutting and when retreating after cutting, repeatability is good.

(2) Since the blade is moved by a cam during cutting, there are fewer malfunctions and high repeatability.

(3) X table movable part 90 and slide guide 8
4 and 85, the X-table movable part 90 is moved back after cutting, and when the cutting is performed again, the positioning accuracy of the cutter, particularly the repeatability, is good.

(4) Since the main shaft part 20 and the slide table part 34 are configured with hydrostatic fluid bearings, the accuracy is high and the vibration absorption property is high. It is difficult for the material to spread, allowing for highly accurate cutting with an excellent surface finish.

(5) As shown in Fig. 16, the slide table part 3
Since the pump 170 for sucking the hydraulic oil is provided in the third oil passage 96 of No. 4, the slide table section 34 can be designed compactly without leaking the hydraulic oil to the outside.

(6) Since the Y table movable part 125 is mounted on the X table movable part 90, when the X table movable part 90 retreats after processing, the Y table movable part 1
Since the cutter 25, the cutter 31, etc. all move back at the same time, the object to be cut 23 can be easily removed.

(7) Since the air cylinder 101 is provided as a means for applying thrust in the direction of moving the X-table movable section 90 closer to the main shaft section 20, there is an advantage that the thrust can be kept constant even if the stroke changes.
Further, when moving the X-table movable section 90 backward, it can be easily done by simply changing the air supply direction.

As described above with reference to the embodiments, the lathe of the present invention includes a main shaft portion that rotatably holds a workpiece;
The lathe includes a frame to which the main spindle is attached, and a slide table that is installed on the frame and holds a blade for cutting the workpiece, the slide table being arranged in an axial direction of the main spindle. X supported by a guide block so that it can slide on
An X-slide table with a movable table part,
It consists of a Y slide table that is provided on the X table movable section and is driven in a direction perpendicular to the sliding direction of the X table movable section, and further includes an X table movable section that is a part of the X table movable section as a main axis. a first driving means that presses and drives the X-table movable part by contacting the X-table movable part from a direction that resists the biasing force of the biasing means; By driving the X-table movable section against the force of the biasing means, the contact relationship between the X-table movable section and the first drive means is released, and the X-table drive section is moved to the main shaft. The second drive is driven in the direction away from the
During cutting, the first drive means is used to perform highly accurate machining, and after machining, a long drive range can be set without requiring high precision. By moving the table using the second driving means, a space necessary for loading and unloading the workpiece can be secured, and a lathe that can easily automatically supply and unload the workpiece can be obtained.

[Brief explanation of the drawing]

Figure 1 is a schematic plan view of a conventional cam-type lathe, Figure 2
The figures are a sectional view taken along the line A-A' in Fig. 1, Fig. 3 is a plan view of a lathe according to an embodiment of the present invention, Fig. 4 is a front view of the same partial cross section, and Fig. 5 is a side view of the same partial cross section. figure,
Fig. 6 is a front sectional view of the main shaft, Fig. 7 is a sectional view taken along line B-B' in Fig. 6 of the main shaft, Fig. 8 is a plan view of the slide table, and Fig. 9 is a sectional view of the main shaft. figure
10 is a sectional view taken along the line D-D' of Fig. 8, which is a sectional view of the slide table part, and Fig. 12 is a sectional view taken along the line F-F' of Fig. 11, which is a sectional view of the stopper. Figure 13 is a cross-sectional view taken along line D-D' in Figure 8, and a cross-sectional view of the slide table section, and Figure 14 is a cross-sectional view taken along line E-- in Figure 8.
Sectional view of the slide table part in E' cross-sectional view, No. 15
The figure is a sectional view of the cam drive section taken along the line GOO'G' in Figure 3.
FIG. 6 is a hydraulic circuit diagram of the lathe of the same embodiment. 4, 23... Work to be cut, 1, 20... Spindle part,
5,31...Knife, 34...Slide table section, 9,35...X slide table, 10,3
6...Y slide table, 84, 85, 124
...Guide block, 13, 14...Cam, 45
...X cam, 46...Y cam, 47, 48... lever, 90... X table movable part, 101... air cylinder.

Claims (1)

[Scope of Claims] 1. A main shaft portion rotatably holding a workpiece material, a frame to which the main shaft portion is attached, and a slide table portion installed on the frame and holding a blade for cutting the workpiece material. A lathe having:
The slide table section includes an X slide table equipped with an X table movable section supported by a guide block so as to be slidable in the axial direction of the main shaft section, and a sliding section of the X table movable section provided on the X table movable section. The Y slide table is driven in a direction perpendicular to the moving direction, and the X
a biasing means for biasing an X-table movable part, which is a part of the slide table, in a direction toward the main shaft; and a biasing means for biasing the X-table movable part that is a part of the slide table; a first driving means for pressing and driving the X-table movable part and the first driving means by driving the X-table movable part against the force of the biasing means; a second driving means for canceling the relationship and driving the X table driving section in a direction away from the main shaft. 2. The biasing means and the second driving means are constituted by the same air cylinder, and the biasing means and the second driving means are constituted by switching the driving direction of this air cylinder. lathe.