JP4901946B2 - Sliding guide device - Google Patents

Description

  The present invention relates to a sliding guide device for a moving body supported so as to be movable through lubricating oil.

  In the field of machine tools and the like, in general, a guide surface is formed on a support such as a bed, a sliding surface is formed on a moving body such as a table, and lubricating oil is supplied between the guide surface and the sliding surface. Then, the guide device is configured to support the movable body on the support body so as to be slidable. In this type of guide device, when the moving body moves, the oil film thickness of the lubricating oil fluctuates and the end of the moving body rises, and the posture of the moving body may become unstable.

  In order to prevent the mobile body from lifting up, a surface pressure adjusting pocket into which the lubricating oil is press-fitted is formed on the surface side of the support body, and a static pressure pocket into which the lubricating oil flows is formed on the back surface side of the support body. There is known a device that is configured to press the moving body in the direction opposite to the floating direction by the pressure oil in the static pressure pocket when the moving body is about to float by the pressure oil in the surface pressure adjusting pocket. (For example, refer to Patent Document 1).

JP 2005-238442 A

  However, the apparatus described in Patent Document 1 has a complicated configuration, and the apparatus becomes large.

  The present invention is a sliding guide device having a support body on which a reference guide surface is formed and a moving body on which a slide surface is slid on the guide surface via lubricating oil. A first groove extending in the moving direction of the moving body is formed on the surface, and the first groove has a depth that generates a flow of lubricating oil in the moving direction of the moving body when the moving body moves. It is characterized by having.

  According to the present invention, the first groove having a depth that generates the flow of the lubricating oil in the moving direction of the moving body is formed on the sliding surface of the moving body. Can be prevented from lifting. When the moving body moves, the lubricating oil accumulated in the rear part flows through the deep part of the first groove to the front part in the moving direction, the lubricating oil accumulates in the rear part, and the pressure of the rear lubricating oil rises and the moving body The phenomenon of rising will disappear.

1 is a diagram illustrating a schematic configuration of a machine tool to which a slip guide device according to an embodiment of the present invention is applied. It is sectional drawing which shows the whole structure of a sliding guide apparatus. It is an expanded sectional view showing the important section composition of the slide guide device concerning an embodiment of the invention. FIG. 4 is an arrow IV view of FIG. 3 showing the arrangement of grooves provided on the sliding surface. (A) is the sectional view on the aa line of FIG. 4, (b) is the sectional view on the bb line of FIG. It is a figure which shows the comparative example of FIG. It is a figure which shows the modification of FIG.

Hereinafter, with reference to FIGS. 1-7, embodiment of the sliding guide apparatus by this invention is described.
FIG. 1 is a diagram showing a schematic configuration of a machine tool to which a slip guide device according to an embodiment of the present invention is applied, and shows a vertical machining center as an example.

  A column 2 is erected on the bed 1, and a spindle head 3 is supported on the column 2 so as to be movable up and down (Z direction). A tool 4 is attached to the spindle head 3 downward. A saddle 5 is supported on the bed 1 so as to be slidable in a horizontal direction (Y direction), and a table 6 is supported on the saddle 5 so as to be slidable in a horizontal direction (X direction) perpendicular to the Y direction. In other words, the spindle head 3, the saddle 5 and the table 6 are slidably supported by the column 2, the bed 1 and the saddle 5 by the sliding guide device 10, respectively. With this configuration, the tool 4 and the workpiece W mounted on the table 6 are relatively moved in the X, Y, and Z directions, and the workpiece W is processed.

  FIG. 2 is a cross-sectional view showing the overall configuration of the sliding guide device 10. The sliding guide device 10 includes a moving body 11 having a sliding surface S1 and a support body 12 having a guiding surface S2 facing the sliding surface S1. The moving body 11 is the spindle head 3, the saddle 5 or the table 6 in FIG. 1, and the support body 12 is the column 2, the bed 1 or the saddle 5, respectively. The movable body 11 and the support body 12 are cast products made of a metal such as cast iron, for example, and are formed by machining as necessary. A nut portion 15 is provided on the lower surface of the movable body 11, and a feed screw 16 extending in the direction perpendicular to the paper surface is screwed to the nut portion 15. The feed screw 16 is rotationally driven by a motor, whereby the moving body 11 slides on the guide surface S2 in the direction perpendicular to the paper surface.

  The moving body 11 is provided with a lubricating oil supply hole 14 so that the lubricating oil is supplied to the sliding surface S1 and the guide surface S2. Lubricating oil is a general sliding surface lubricating oil having a viscosity of about 68 cst, and is supplied by a pump, for example, several ml every several minutes. The moving body 11 is configured to embrace both ends of the support body 12, and a sliding surface S <b> 1 and a guide surface S <b> 2 are provided on each contact surface of the moving body 11 and the support body 12.

  According to such a sliding guide device 10, since the moving body 11 is supported so as to be slidable on the entire surface, a higher support rigidity is obtained compared to the rolling guide device, the load capacity is large, and the vibration absorption and impact resistance are improved. Also excellent. For this reason, it is suitable for use in a machine tool or the like that needs to support the workpiece W with high precision. By applying the sliding guide device 10 to the machine tool, the workpiece W can be used regardless of load fluctuations during workpiece machining. It can be processed with high accuracy.

  On the other hand, in this type of sliding guide device 10, when the moving body 11 is moved at high speed on the guide surface S 2, lubricating oil accumulates between the guide surface S 2 at the rear of the moving body 11 and the sliding surface S 1. As a result, the end of the moving body 11 is lifted. Such lifting of the moving body 11 may adversely affect the processing accuracy. In order to prevent this, in the present embodiment, the sliding surface S1 of the sliding guide device 10 is grooved as follows.

  FIG. 3 is an enlarged cross-sectional view showing a main configuration of the sliding guide device 10 according to the embodiment of the present invention, and FIG. 4 is a plan view of the sliding surface S1 (an arrow IV view in FIG. 3). . 3 corresponds to a cross-sectional view taken along line III-III in FIG. Below, the X direction of FIG. 4 which is the moving direction of the mobile body 11 is called a longitudinal direction, and the Y direction of FIG. 4 orthogonal to this is called a width direction.

  A low friction sliding material 13 having a predetermined thickness t0 (for example, about 1 mm) is affixed to the surface of the moving body 11 on the guide surface S2 side, and a sliding surface S1 is formed by the low friction sliding material 13. The low friction sliding material 13 may be made of a material having a small friction coefficient and high wear resistance, and may be made of a resin material such as a fluororesin. Although illustration is omitted, the sliding surface S1 is subjected to scoring or machining to form fine irregularities over the entire range in order to maintain lubricity.

  An elongated first groove 15 (hereinafter referred to as a longitudinal groove) extending in the longitudinal direction is formed in the center portion in the width direction of the sliding surface S1. The sliding surface S1 is formed with a plurality of elongated second grooves 16 (hereinafter referred to as transverse grooves) that communicate with the longitudinal grooves 15 and extend on both sides in the width direction. The lubricating oil supply hole 14 is open at the longitudinal center of the longitudinal groove 15.

  5A is a sectional view of the longitudinal groove 15 (a sectional view taken along the line aa in FIG. 4), and FIG. 5B is a sectional view of the lateral groove 16 (a sectional view taken along the line bb in FIG. 4). It is. As shown in FIG. 5A, the vertical groove 15 has a rectangular groove cross section with a width wa and a depth ta, and is formed by groove processing using a normal end mill. The vertical groove 15 functions as a feedback circuit that generates a flow of lubricating oil in the moving direction as indicated by an arrow B in FIG. 3 when the movable body 11 is moved in the direction of arrow A in FIG. Although this is not provided in the moving body of the actual machine tool, pressure detectors P1 and P2 are attached to the front and rear of the longitudinal groove 15 of the moving body 11 of the experimental apparatus, respectively (the dashed line in FIG. 3). It was found by observing the change in pressure during movement.

  When 68 cst of lubricating oil is used, when the depth of the longitudinal groove 15 is 3 mm, the rear pressure P2 becomes larger than the front pressure P1, and a phenomenon occurs in which the lubricating oil accumulates at the rear of the longitudinal groove 15. When the depth of the longitudinal groove 15 is 10 mm, the rear pressure P2 and the front pressure P1 have substantially the same value, and it was found that the lubricating oil circulates in the moving direction as indicated by the arrow B. When the longitudinal groove 15 is further deepened, the pressures P2 and P1 have substantially the same value, and the circulation shown by the arrow B of the lubricating oil occurs, but the volume of the longitudinal groove 15 becomes too large and the supplied lubricating oil Is stored in the longitudinal groove 15, and another problem arises that it becomes difficult to reach the entire sliding surface S <b> 1 through the lateral groove 16 described later. Therefore, the appropriate depth ta of the longitudinal groove 15 is about 10 mm when the viscosity of the lubricating oil is 68 cst. Note that the width wa of the longitudinal groove 15 is narrower than the depth ta, for example, about 6 mm.

  On the other hand, the lateral groove 16 functions as a lubrication circuit that guides the lubricating oil in the width direction of the moving body 11 and spreads the oil over the entire sliding surface S1 to improve the lubricity. As shown in FIG. The lateral grooves 16 are arranged at substantially equal intervals in the longitudinal direction. In order to spread a small amount of oil over the entire surface by the lateral groove 16, it is preferable that the groove depth tb is shallow and the surface area of the groove is wide. Therefore, as shown in FIG. 5B, the lateral groove 16 is formed in a gently curved shape so that the groove width gradually decreases in the depth direction, and has a maximum width Wb (for example, about 5 mm) at the surface portion. It has become. The depth tb of the lateral groove 16 is preferably shallower than the thickness t0 of the low friction sliding member 13, for example, about 0.5 mm or less. In addition, the depth of the unevenness of the scraping process or the machining process on the sliding surface S1 is shallower than the depth tb of the lateral groove 16 and is, for example, 0.12 mm.

  When lubricating oil is supplied to the vertical groove 15 via the lubricating oil supply hole 14, the lubricating oil flows in the width direction of the sliding surface S1 via the horizontal groove 16, and spreads over the entire sliding surface S1. For this reason, it is possible to prevent oil shortage between the sliding surface S1 and the guide surface S2, the friction coefficient of the sliding surface S1 is reduced, and wear of the sliding surface S1 can be suppressed.

  At this time, when the moving body 11 moves on the guide surface S2 in the direction A in FIG. 3 at a high speed, the lubricating oil is left in the vertical groove 15 without following the movement of the moving body 11, and the movement in the vertical groove 15 is performed. Accumulate on opposite side. The accumulated lubricating oil rises along the end wall 15a of the vertical groove 15 and flows in the moving direction of the moving body 11 as indicated by an arrow B in FIG. Thereby, the flow of the lubricating oil in the moving direction of the moving body 11 is generated in the vertical groove 15, the oil pressure on the opposite side in the moving direction in the vertical groove 15 is reduced, and the floating of the moving body 11 can be prevented.

According to the present embodiment, the following operational effects can be achieved.
(1) Since the elongated vertical groove 15 functioning as a feedback circuit for generating a flow of lubricating oil in the moving direction is formed on the sliding surface S1 of the moving body 11 in the moving direction (longitudinal direction) of the moving body 11. The lifting of the mobile body 11 can be prevented with a simple configuration. That is, for example, as shown in FIG. 6, a feedback circuit 151 in the moving direction is formed inside the moving body 11, and the feedback circuit is compared with the case where the lubricating oil is fed back via the feedback circuit 151 as shown by the arrow B in the figure. Is easy to process.

(2) Since the sliding surface S1 of the moving body 11 communicates with the longitudinal groove 15 and has a plurality of elongated lateral grooves 16 extending in the width direction, the lubricating oil supplied into the longitudinal groove 15 is supplied to the sliding surface S1. The entire surface can be spread, and the lubricity on the sliding surface S1 is improved.
(3) Since the depth ta of the vertical groove 15 is made deeper than the depth tb of the horizontal groove 16, the vertical groove 15 can function as a feedback circuit.
(4) Since the vertical groove 15 is formed so that the groove cross section has a substantially rectangular shape, the vertical groove 15 can be processed using a normal end mill, and the groove processing is easy.
(5) Since the lateral groove 16 is formed so that the groove width gradually becomes narrower in the depth direction, the area of the oil groove in contact with the guide surface S2 increases, and the sliding resistance can be reduced.
(6) Since the lubricating oil supply hole 14 is provided in communication with the vertical groove 15, the supplied lubricating oil is once stored in the vertical groove 15, and the stored lubricating oil gradually slides through the lateral groove 16. It can be distributed to the surface S1.

  In the above embodiment (FIG. 4), a single vertical groove 15 (first groove) is formed on the sliding surface S1 of the moving body 11, and a plurality of horizontal grooves 16 ( The second groove) is formed, but the arrangement of the first groove and the second groove is not limited to this. For example, as shown in FIG. 7A, a plurality of vertical grooves 15 are formed on the sliding surface S1, a plurality of horizontal grooves 16 are communicated with each vertical groove 15, and a lubricating oil supply hole 14 is formed in the central vertical groove 15. May be communicated. Further, as shown in FIG. 7B, the pair of lateral grooves 16 and the pair of grooves 152 having the same depth as the lateral grooves 16 may form grooves so as to surround the entire sliding surface S1. . The horizontal groove 16 may be omitted, and only a single or a plurality of vertical grooves 15 may be processed into the sliding surface S1.

  The shape of the longitudinal groove 15 is not limited to that described above as long as it has a depth ta that generates a flow of lubricating oil in the moving direction of the moving body 11 when the moving body 11 moves. Further, the shape of the lateral groove 16 is not limited to that described above as long as it communicates with the longitudinal groove 15 and extends in a direction substantially perpendicular to the moving direction of the moving body 11. The groove shape is not linear but may be curved. Although the lubricating oil supply hole 14 for supplying the lubricating oil to the sliding surface S1 is provided in communication with the vertical groove 15, the supply passage may be provided at another position.

  The example in which the sliding guide device 10 is applied to a vertical machining center has been described above, but the sliding guide device according to the present invention can be similarly applied to a horizontal machining center and other machine tools. Moreover, it is applicable similarly to other machines (for example, a material testing machine, various measuring instruments, etc.) which require high support rigidity.

DESCRIPTION OF SYMBOLS 10 Sliding guide apparatus 11 Moving body 12 Support body 14 Lubricating oil supply hole 15 Vertical groove (1st groove)
16 Horizontal groove (second groove)

Claims (4)

A sliding guide device having a support body on which a guide surface serving as a reference is formed, and a moving body on which a sliding surface sliding on the guide surface via lubricating oil is formed;
A first groove extending in the moving direction of the moving body is formed on the sliding surface,
The sliding guide device according to claim 1, wherein the first groove has a depth that generates a flow of lubricating oil in a moving direction of the moving body when the moving body moves. In the sliding guide apparatus of Claim 1,
A sliding guide device in which a plurality of second grooves are formed on the sliding surface so as to communicate with the first groove and extend in a direction substantially perpendicular to the moving direction of the moving body. In the sliding guide apparatus of Claim 2,
The sliding guide device in which the first groove is formed deeper than the second groove. In the sliding guide apparatus of any one of Claims 1-3,
A sliding guide device in which a supply passage for supplying lubricating oil to the sliding surface is provided in communication with the first groove.

Images