JP2018103321A - Work-piece vice - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a work vise capable of supporting a work with high rigidity in a work vise for gripping the work with the center of the work as a reference. SOLUTION: A guide plate elongated in the screw axis direction is fixed to both sides of a screw shaft that opens and closes the base base symmetrically. The guide plate fixed to one base and the guide plate fixed to the other base are slidably fitted to the guide groove of the base in a state of being stacked in two. A plurality of guide strips in the screw axis direction are formed between each guide plate and the inner wall surface of the guide groove, and a surface that regulates the upward movement of the guide plate when the work is gripped is machined with high accuracy. .. [Selection diagram] Fig. 6

Description

  The present invention relates to a work vise that is used to hold a workpiece by attaching it to a table of a machine tool, and more particularly to a work vise that is particularly suitable for a machine tool that performs machining on the basis of the center of the workpiece, such as a 5-sided machine. .

  A general work vise has a structure in which a work is gripped between a fixed base integrated with a base fixed to a table of a machine tool and a movable base that advances and retreats toward the fixed base. In a 5-sided machine or a machining center, machining is often performed with the center of the workpiece as a reference. However, when machining a workpiece fixed to a table using a workpiece vise with the above structure, if the vise or workpiece is thermally deformed, An error (bias) occurs in the machining position with respect to the center of the workpiece.

  Accordingly, when machining is performed with the center of the workpiece as a reference, it is preferable to grip the workpiece with a vise that can hold the workpiece with the center of the workpiece as a reference. The applicant of the present application has proposed a work vise capable of gripping a work with high rigidity on the basis of the center of the work in Patent Document 1.

  In the work vise described in Patent Document 1, the screw shaft for opening and closing the base includes right and left screws on both sides in the axial direction, and the nut member of the base is screwed to the left and right screws. A long and narrow guide plate is fixed to both sides of the screw base, and the guide plate fixed to one base and the guide plate fixed to the other base are slidably in surface contact with each other. It is slidably fitted into a guide groove in the direction of the screw shaft.

  In order to regulate the position of the base in the vertical direction with respect to the base, the work vise described as an example in Patent Document 1 is provided between the inner guide plate and the inner inner wall surface of the guide groove, and on the outer side. One guide strip in the screw shaft direction is provided between the guide plate and the outer inner wall surface of the guide groove.

  Further, the applicant of the present application in Patent Document 2 has a function of pressing a gripped work against a vise base or a cradle placed on the base by a gripping reaction force acting on the base from the work when the work is gripped. We propose a base for work vice equipped with. As shown by an imaginary line in FIG. 2, the base described in Patent Document 2 holds a workpiece between the front surface of the base block 51 fixed to the base 45 and the back surface of the base block 52 that grips the workpiece. In addition, a component force Fv of the gripping reaction force F acting on the base block 52 is provided with a multi-step inclined sliding contact surface 53 that is a direction to push the base block 52 downward.

JP 2012-245587 A International Publication No. 2002/048809 Pamphlet

  When a workpiece gripped by the workpiece vise is processed by a five-face processing machine, forces in various directions are applied to the workpiece. When various workpieces were machined with the work vise described in Patent Document 1, when machining the workpiece in the screw axis direction and when machining the workpiece in the direction of pressing the workpiece against the work vise base, high machining accuracy was achieved. Was able to be realized. On the other hand, when the side surface of the workpiece W indicated by arrows Pv and Ph in FIG. 5 is processed from the bottom to the top, or when the upper surface of the workpiece W is processed in the left-right direction in FIG. Even with the same structure, it became clear that there was a difference in machining accuracy depending on the individual work vice.

  In view of the need for a work vise capable of performing heavy cutting and realizing higher machining accuracy in machining a workpiece by a five-face machine, the present invention is based on the above knowledge and disclosed in Patent Document 1. It is an object of the present invention to provide a work vice that can withstand higher machining reaction force and perform higher-precision machining without increasing the size of the vice.

  The work vise of the present invention has the same basic structure as the work vise described in Patent Document 1, and is provided on the base 1 in parallel with the screw shaft 3 that opens and closes the facing base 45 (45a, 45b). A plurality of guide strips are respectively provided on the sliding contact surfaces 8 (8a, 8b) between the inner wall surface 15 (15a, 15b) of the guide groove 14 having a U-shaped cross section and the guide plate 43 (43a, 43b) for guiding the base 45. 6 (6a, 6b) and 7 (7a, 7b) are provided, and the surface of each guide strip 6, 7 that prevents the guide plate 43 from moving upward grips the workpiece W. The control surfaces c and d are sometimes pressed against each other, and are provided with a clearance e that allows a machining error of the guide strips 6 and 7 between the surfaces that prevent the guide plate 43 from moving downward. It is characterized by.

  A preferable work vise of the present invention is provided with a base 5 having a slope 53 that generates a component force Fv in a direction of pushing the work W toward the base 1 by a reaction force F acting when the work W is gripped. It is a work vice.

  The work vise of the present invention has the same basic structure as that of the work vise described in Patent Document 1, that is, the base 1 fixed to the table of the machine tool is pivotally supported at both ends so as to be rotatable and axially movable. The screw shaft 3 is provided. The screw shaft 3 is provided with a right screw and a left screw of the same lead on both sides in the axial direction with the longitudinal center as a boundary.

  Similar to the work vise described in Patent Document 1, the right and left screws of the screw shaft 3 are screwed with the nut members 4 (4a and 4b) of the base 45, respectively. An elongated guide plate 43 is fixed in the axial direction of the screw shaft 3 at positions on both sides of the screw shaft 3 in the direction perpendicular to the axis. The guide plate (inner guide plate) 43a fixed to one of the right and left screw bases 45a and the guide plate (outer guide plate) 43b fixed to the other base 45b are opposed to each other. The two planes that are in contact with each other are slidably in surface contact with each other. The two overlapping guide plates 43a and 43b are slidably fitted in the guide grooves 14 formed in the base 1 in the screw shaft direction.

  In the work vise of the present invention, a plurality of guide strips 6 and 7 in the screw shaft direction are formed on the sliding contact surface 8 between the guide plate 43 and the inner wall surface 15 of the guide groove. Each of the guide strips 6 and 7 is formed by a pair of concave grooves 46 (46a and 46b) and protrusions 16 (16a and 16b) which are slidably fitted in these concave grooves.

  A preferred structure of the present invention is such that the sliding contact surface between the inner guide plate 43a and the outer guide plate 43b has a structure in which the relative movement direction is guided by the guide key 49 in the screw shaft direction. The lower surface of the intermediate concave groove 48 (48a, 48b) that accommodates the surface is the same height as the lower surface of the lowermost guide strip among the plurality of guide strips. Thereby, the height position of the intermediate concave groove 48 can be processed accurately, and the vertical position between the inner and outer guide plates 43a and 43b can be guided more accurately.

  Similar to the work vise described in Patent Document 1, the screw shaft 3 is pivotally supported by the base at both ends in a state where tension is applied. A base 45 is fixed to each nut member 4, and a base 5 according to the shape of the work is attached to the base. When the screw shaft 3 is rotated, the facing caps 5 and 5 are advanced and retracted symmetrically around an intermediate position in the advancing and retracting direction.

  As with the work vise described in Patent Document 1, the work vise according to the present invention can increase the guide length of the base and add tension to the screw shaft in the work vise that grips the work with reference to the center of the work. It is possible to easily increase the rigidity of the base in the moving direction by pivotally supporting both ends of the base on the base.

  Furthermore, the work vise of the present invention includes a plurality of guide strips for guiding the vertical position of the guide plate for guiding the base, and firmly and highly accurately restricts the upward movement of the guide plate when the workpiece is gripped. Therefore, even when an upward machining reaction force or a machining reaction force crossing the screw shaft is applied to the workpiece, the workpiece can be firmly fixed at a set position.

  Therefore, according to the work vice of the present invention, there is an effect that it is possible to obtain a work vise having a high support rigidity capable of gripping the work with reference to the center of the work.

Overall perspective view showing one embodiment of a work vice Sectional side view in the center of the vise of FIG. Plan view Front Section A sectional view of FIG. Enlarged view of the main part of FIG.

  Next, an embodiment of the present invention will be described with reference to the drawings. In the figure, 1 is a base. As shown in FIG. 5, the base 1 includes a bottom plate 11, a side plate 12 having a substantially triangular cross section on both sides, and a middle convex portion 13 having a height lower than the side plate 12, and U on the top surface of the middle convex portion 13. The groove has a stepped surface shape, and a guide groove 14 having a rectangular cross section is formed between the side plate 12 and the middle convex portion 13 on both sides.

  The guide grooves 14 are formed on both sides of the middle convex portion 13, and on the inner side (middle convex side) inner wall surface 15a and on the outer side (side plate side) inner wall surface 15b, there are two inner ribs 16a, 17a and outer sides, respectively. The ridges 16b and 17b are formed. Both ends of the middle convex portion 13 are scraped off by the thickness of the bearing block 2 described later, and the length is shorter than the length of the bottom plate 11 and the side plate 12 by that amount.

  Three lateral screw holes 19 for fixing a bearing block 2 to be described later are provided on the bottom plate 11 side of both ends from which the middle convex portion 13 is cut off. A plurality of mounting holes 18 for inserting bolts for fixing the base 1 to the table of the machine tool are provided in a portion outside the guide groove 14 of the side plate 12 having a substantially triangular cross section.

  Reference numeral 2 denotes a bearing block. The bearing block 2 has protrusions 20 and 21 positioned on the extended portions of the inner base ridges 16a and 17a on both side surfaces of the rectangular parallelepiped block, and shaft holes 22 through which ends of the screw shaft 3 to be described later pass. I have. Counterbore holes 23 and 24 are provided on both axial sides of the shaft hole 22. The bearing block 2 is fixed to both end faces of the middle convex portion 13 of the base 1 with a lateral bolt 25 with the deeper outer counterbore 23 on the outside.

  Reference numeral 3 denotes a screw shaft for screwing the base back and forth. The screw shaft 3 is located immediately above the middle convex portion 13 of the base. The screw shaft 3 is formed with a right screw 31a and a left screw 31b having the same lead with the longitudinal center as a boundary, and both ends thereof are provided with male screws 32 for fixing both ends to the base so as not to be axially movable. ing. The screw shaft 3 is inserted into the shaft hole 22 of the bearing block 2 whose both ends are fixed to the base, and both axial ends of the screw shaft 3 are fixed by the outer nuts 34 in which the thrust bearing 33 fitted in the outer counterbore hole 23 is screwed to the male screw 32. By tightening, the shaft is supported so that it cannot move in the axial direction and is rotatable in a state where a tension is applied.

  A hexagon head 35 for fitting a tool for rotating the screw shaft 3 is attached to both ends of the screw shaft passing through the outer nut 34. A small load thrust bearing 36 and an inner nut 37 for lightly tightening the thrust bearing 36 are accommodated in the inner bore 24 of the bearing block. Although not shown in the drawing, the outer nut 34 and the inner nut 37 are provided with a detent for fixing the nut position after being tightened.

  Nut members 4a and 4b are screwed into the right screw 31a and the left screw 31b of the screw shaft 3, respectively. The nut member 4 (4a, 4b) includes a female screw that is screwed into the screw shaft 3 at the center of the U-shaped cross-section protruding portion 41, and includes flanges 42 (42a, 42b) that extend from the upper part to both sides. . An inner guide plate 43a is fixed to the flange 42a of one nut member 4a, and an outer guide plate 43b is fixed to the flange 42b of the other nut member 4b. The inner guide plate 43a and the outer guide plate 43b are fitted in the guide groove 14 of the base so as to be slidable in the screw axis direction in a state where their opposing surfaces are in slidable surface contact.

  The guide plate 43a and the outer guide plate 43b are flat plates elongated in the longitudinal direction of the screw shaft 3, and the surfaces that are in sliding contact with each other and the surfaces that are in contact with the inner wall surface 15 of the guide groove are finished in exactly parallel planes. Yes. On the surface facing the inner inner wall surface 15a of the guide groove of the inner guide plate 43a and the surface facing the outer inner wall surface 15b of the guide groove of the outer guide plate 43b, the ridges 16a, 17a and 16b, 17b formed on these inner wall surfaces. Grooves 46a, 47a and 46b, 47b are slidably fitted.

  Further, in the illustrated embodiment, intermediate concave grooves 48a and 48b parallel to the concave grooves 46 and 47 are provided at the same height on the sliding contact surfaces of the inner guide plate 43a and the outer guide plate 43b. A guide key 49 fixed to one of the intermediate grooves is slidably fitted into the other intermediate groove.

  A base 5 having the structure shown in FIG. 2 is attached to the opposing surfaces of the bases 45a and 45b screwed into the right and left screws of the screw shaft 3, respectively. As described above, the base 5 generates a component force Fv in a direction in which the work is pushed downward (on the bottom side of the vise base) when the work is gripped. As a reaction of this component force, a force in a direction of pushing the base 45 upward is applied to the base 45 when a workpiece is gripped.

  6 shows the relationship between the inner wall surface 15 (15a, 15b) of the guide groove 14 and the inner and outer guide plates 43 (43a, 43b) when the workpiece is gripped by the work vice of the present invention, and the ridges 16, 17 ( 16a, 17a, 16b, 17b) and the grooves 46, 47 (46a, 47a, 46b, 47b) are exaggeratedly shown in sliding contact and loose-fitting relationships.

  That is, the restriction surfaces c and d that restrict the upward movement of the guide plate 43, the lower surface of the protrusions 16 and 17 provided on the inner wall surface of the guide groove 14 and the guide plates 43a and 43b in the illustrated example. The upward surfaces of the grooves 46 and 47 have high dimensional accuracy and surface accuracy, and are necessary for sliding and machining errors between the upper surfaces of the ridges 16 and 17 on the opposite side and the downward surfaces of the grooves 46 and 47. The guide groove 14 of the base and the inner and outer guide plates 43 are processed so that a free play e exists. This processing can be realized by processing the processing dimensions f and g from the upper surface of the guide plate 43 to the lower surfaces of the concave grooves 46 and 47 and the dimension h between the upper surfaces of the protrusions 16 and 17 with high accuracy.

  In addition, the intermediate concave groove 48 (48a, 48b) is provided with a surface having the same height as the lower surface of the lowermost concave groove 47 in the guide strip provided with a plurality of lower surfaces.

  The work vise of the illustrated embodiment includes a cover 60 that protects the screw shaft 3 and the female thread of the nut member 4 that is screwed into the screw shaft 3 from chips, as in the work vise described in Patent Document 1. That is, a guide surface 44 having a shallow trapezoidal shape in a side view for the cover 60 is formed in a central portion of the upper surface of the nut member 4 above the protruding portion 41.

  The nut member 4 is fixed to the base 45 with vertical bolts 47. The vertical bolt 47 passes through the flange 42 of the nut member 4 and is screwed to the guide plate 43. The vertical bolt 47 fixes the nut member 4 to the base 45 and the guide plate 43 to the base 45. It is fixed.

  In the central portion of the base 45 where the vertical bolt 47 does not penetrate, a shallow mountain-shaped groove is provided on the bottom surface in a side view, and between the upper surface of the central portion of the nut member 4 and the lower surface of the central portion of the base 45, A cover passage hole 61 that is slit-like through which the cover 60 can slidably pass and bends in a shallow trapezoidal shape in a side view is formed.

  The cover 60 has a flexible belt shape and is mounted in a state where both ends thereof are fixed to the upper edge of the bearing block 2. The height of the shallow trapezoidal guide surface 44 on the nut member 4 side forming the lower surface of the cover passage hole 61 corresponds to the thickness of the flange 42 of the nut member, and the cover passage hole has a shallow trapezoidal shape. Thus, the cover 60 is inserted between the nut members 4 on both sides into a notch groove 62 provided on both inner edges on the inner upper edge of the inner guide plate 43a.

  When the work is gripped by the work vice of the illustrated embodiment, the work W is pushed downward by the action of the inclined sliding contact surface 53 of the base 5, and the pedestal 55 placed on the upper surface of the guide plate 43 or the upper surface (FIG. 2). The vertical position of the workpiece on the vise is defined. Then, an upward force acts on the base 45 as a reaction force that presses the work downward, and this upward force is transmitted to the guide plate 43 that is integrally fixed to the base 45. In the work vise of this invention, since the guide plate 43 is restricted from moving in the vertical direction by the plurality of guide strips 6 and 7, it can withstand a larger vertical force. Further, since the plurality of guide strips 6 and 7 accurately regulate the position of the guide plate 43 in the upward direction, the workpiece can be more firmly fixed at the accurate position. In particular, the tool is shown by the arrow Pv in FIG. The workpiece can be fixed accurately and firmly when the workpiece is processed by moving in the direction indicated by Ph.

  Further, according to the structure of the work vise of the present invention, the sufficiently thick screw shaft 3 can be provided, and both ends of the screw shaft are supported by the base 1 in a state where tension is applied to the screw shaft. The rigidity of the base 45 can be sufficiently increased.

DESCRIPTION OF SYMBOLS 1 Base 3 Screw shaft 4 (4a, 4b) Nut member 5 Cap 6 (6a, 6b) Guide strip 7 (7a, 7b) Guide strip 8 (8a, 8b) Sliding contact surface 14 Guide groove 15 (15a, 15b) Inner wall 16 (16a, 16b) Projection 43 (43a, 43b) Guide plate 45 (45a, 45b) Base 46 (46a, 46b) Groove 48 (48a, 48b) Intermediate groove 49 Guide key 53 Slope c, d Restriction surface e Space F Reaction force W Workpiece

Claims (4)

A base fixed to the table of the machine tool;
A screw shaft that is rotatably supported at both ends on the base in a state where tension is applied with one side in the longitudinal direction as a left-hand thread and the other side as a right-hand thread;
A base that is screwed into the left and right threads of the screw shaft,
Guide grooves provided in the base parallel to the screw shaft on both sides of the screw shaft;
An inner guide plate in sliding contact with the inner wall surface of the guide groove near the screw shaft;
An outer guide plate that is in sliding contact with both the inner wall surface on the side farther from the screw shaft of the guide groove and the inner guide plate;
A guide strip provided on the sliding contact surface between the inner wall surface and the guide plate in parallel with the screw shaft and regulating the sliding direction of each guide plate in a direction parallel to the screw shaft;
The outer guide plates on both sides of the screw shaft are fixed integrally to one base, the inner guide plates on both sides of the screw shaft are fixed integrally to the other base,
In the work vice where the outer guide plate and the inner guide plate move with the same stroke in the opposite direction to the base by the rotation of the screw shaft,
A work vise comprising a plurality of the guide strips on the sliding surface.   Of the surfaces of the plurality of guide strips facing in the vertical direction, the surface that prevents the guide plate from moving upward is defined as a restriction surface, and the surface that faces upward and the downward direction of the guide plate is prevented from moving downward. The work vice according to claim 1, wherein the work vice is provided with a clearance allowing a machining error of these guide strips between the facing surface.   The work vise according to claim 2, wherein a base having a slope in a direction in which the work is pressed downward relative to the base by a work reaction force of the work is attached to the base. The inner guide plate and the outer guide plate are provided with an intermediate concave groove parallel to the guide strip at the same height of the sliding contact surface, and a guide key fixed to one of the intermediate concave grooves is in the middle of the other. In the work vice according to claim 1, 2 or 3, which is slidably fitted in the groove.
A work vise in which the lower surface of the intermediate groove is a surface having the same height as the lower surface of the lowermost guide strip among the plurality of guide strips.

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