Work vise and cap for vise

Abstract

To provide a work vise for being used when a relatively small-sized machine component is processed, which can perform processing with a high degree of accuracy and which has high gripping accuracy and gripping rigidity enabling deeper cutting, and a cap.SOLUTION: An upper edge part with a vertical width of 2-5 mm below an upper edge of a flat gripping surface 5s for gripping a workpiece w of a cap and a cap table of a work vise has a plurality of triangular cross-section projections with a ridge formed by a downward inclined plane and a top surface perpendicular to the gripping surface 5s, and a plurality of grooves 36 for cutting the projections at a right angle in a plurality of locations.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a vice jaw that is attached to the table of a machine tool to grip a workpiece, and to a work vice that is particularly suitable for machine tools that perform machining based on the center of the workpiece, such as five-face machining centers. [Background technology]

[0002] A typical work vice has a structure in which a workpiece is gripped between a fixed jaw that is integrated with a base fixed to the table of a machine tool, and a movable jaw that moves forward and backward toward this fixed jaw. In five-face machining centers and machining centers, machining is often performed based on the center of the workpiece, but when machining a workpiece fixed to a table using a work vice with the above structure, thermal deformation of the vise or workpiece will cause an error (bias) in the machining position based on the center of the workpiece.

[0003] Therefore, when machining is performed based on the center of the workpiece, it is preferable to hold the workpiece with a vice that can hold the workpiece based on the center of the workpiece. In Patent Documents 1 and 2, the applicant of the present application has proposed a work vice that can hold the workpiece with high rigidity based on the center of the workpiece.

[0004] The work vice described in Patent Documents 1 and 2 has a screw shaft that opens and closes the jaws, which is equipped with right-handed and left-handed threads on both axial sides, with nut members of a jaw base screwed onto the left and right threads, and long, thin guide plates fixed to both sides of the screw shaft of the jaw base in the screw axis direction, with the guide plates fixed to one jaw base and the guide plates fixed to the other jaw base being in slidable surface contact and slidably fitted into guide grooves in the screw axis direction provided on the base.

[0005] In the work vices described as examples in Patent Documents 1 and 2, guide strips in the screw axis direction are provided between the inner guide plate and the inner wall surface of the guide groove, and between the outer guide plate and the outer wall surface of the guide groove, in order to regulate the vertical position of the jaw base relative to the base. In addition, a fitting pair shaped like a saw blade in a side view is provided between the back surface of the jaw base and the front surface (gripping side surface) of the jaw base, which presses the jaw base downward with a gripping reaction force, so that when the workpiece is gripped, the jaw and therefore the workpiece are pressed against the base side.

[0006] In addition, the work vice proposed in Patent Document 2 has multiple guide ribs that guide the forward and backward movement of the jaw base, thereby increasing the gripping rigidity of the workpiece w and enabling more precise machining. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2012-245587 A [Patent Document 2] JP 2018-103321 A Summary of the Invention [Problem to be solved by the invention]

[0008] Due to rising labor and material costs in the supply chain, there is a growing demand to be able to perform heavier cutting even on relatively small machine parts and to reduce as much as possible the labor hours and material waste required to remove scratches that occur on the gripping surface of the workpiece during processing.In light of this, the objective is to obtain a work vise and jaws with higher gripping accuracy and gripping rigidity. [Means for solving the problem]

[0009] The jaw 5 of the present invention is a jaw which is generally fixed with bolts to the jaw base 7 of a vise, and is provided with a plurality of triangular cross-section protrusions 31 each having an apex 34 formed by an upper surface 32 perpendicular to the gripping surface 5s and a downwardly inclined surface 33 at an upper edge portion 2 to 5 mm below the upper edge of a flat, smooth gripping surface 5s which grips the workpiece w, and a plurality of grooves 36 which cut the protrusions 31 at right angles at multiple points.

[0010] The jaws 5 are made of a metal harder than the workpiece w, and the multiple triangular cross-section ridges 31 parallel to the upper edge are formed by machining multiple triangular cross-section grooves 35 on the upper edge of the flat gripping surface 5s. Therefore, the triangular cross-section ridges 31 have a sharp apex 34 that does not protrude from the flat workpiece gripping surface 5s.

[0011] The jaw 5 of the present invention has a flat gripping surface to which a receiving plate 38 is attached for receiving the bottom surface of the workpiece w, and the upper edge portion provided with the triangular cross-section protrusion 31 grips the workpiece.

[0012] The work vice of this invention has a jaw base 7 of a work vice having the structure described in Patent Document 1 or 2, and multiple triangular cross-section protrusions 31 and grooves 36 similar to those provided on the jaw 5 are machined into the jaw base 7. Effect of the Invention

[0013] The jaw 5 and jaw base 7 of the work vice of this invention grip and fix the workpiece w with the apex 34 of the triangular cross-section protrusion 31 provided on their upper edge and the cut end of the apex 34 cut by the groove 36 biting into the workpiece w, so that the gripping reaction force can firmly fix the workpiece w while pressing it against the upper surface of the receiving plate 38, making heavy cutting possible as well as high-precision finishing processing, and enabling a significant reduction in the machining time and setup time of machine parts. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view showing an embodiment of a work vice; [Diagram 2] Plan view [Diagram 3] Front (end) view [Figure 4] Center section side view [Diagram 5] Cross-sectional view of part A in Figure 4 [Figure 6] Front view of the base [Figure 7] Front view of the base [Figure 8] Enlarged side view of the workpiece gripping part DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The present invention will be described below with reference to the attached drawings showing a state in which a jaw according to the present invention is attached to a work vice according to the present invention and a work w is being gripped. 1 to 5, reference numeral 1 denotes a base of the work vise. As shown in the figures, base 1 comprises a bottom plate 11 and fixed plates 12 extending on both sides thereof. Bottom plate 11 has a cross-sectional shape with a central convex portion 13 having a U-shaped groove formed on its top surface, and guide grooves 14 having a rectangular cross section are formed between the fixed plates 12 on both sides and central convex portion 13.

[0016] The guide groove 14 is formed on both sides of the central convex portion 13, and inner ridges 16a, 17a and outer ridges 16b, 17b are formed on the inner wall surface (on the central convex portion side) and the inner wall surface (on the fixed plate side), respectively. Both ends of the central convex portion 13 are cut off by the thickness of a bearing block 2, which will be described later, and the length of the central convex portion 13 is shorter than the length of the bottom plate 11 and the fixed plate 12 by that amount.

[0017] The fixed plate 12 has three reinforcing ribs 55 that are approximately triangular when viewed from the front (end surface), and is provided, on the part outside the guide groove 14, with multiple mounting holes 18 for inserting bolts to fix the base 1 to the table of the machine tool, and multiple screw holes 56 for erecting the support material 51 described later.

[0018] Reference numeral 2 denotes a bearing block that supports the screw shaft 3 so that it cannot move axially but can rotate, and is fixed to both end faces of the central convex portion 13 of the base 1 with horizontal bolts 21. The bearing block 2 has a shaft hole 22 through which the end of the screw shaft 3 described later passes.

[0019] The screw shaft 3 is located directly above the central convex portion 13 of the base. The screw shaft 3 is formed with right-hand threads 3a and left-hand threads 3b of equal lead across the longitudinal center, and is provided with male threads 3c at both ends for fixing both ends to the base so as to be immovable in the axial direction. The screw shaft 3 is inserted into a shaft hole 22 of a bearing block 2 whose both ends are fixed to the base, and is supported so as to be immovable in the axial direction but rotatable under tension by fastening both axial ends with outer nuts 24 in which thrust bearings 23 are screwed onto the male threads 3c.

[0020] Hexagonal heads 25 are attached to both ends of the screw shaft that passes through the outer nut 24, into which a tool for rotating the screw shaft 3 is fitted. A small-load thrust bearing 26 and an inner nut 27 that lightly tightens it are provided on the inside of the thrust bearing 23 of the screw shaft 3.

[0021] Nut members 4 (4a, 4b) are screwed onto the right-hand thread 3a and the left-hand thread 3b of the screw shaft 3. The nut member 4 has a female thread at the center of a U-shaped cross-sectional protrusion 41 that screws onto the screw shaft 3, and a flange 42 extending from the upper portion to both sides. An inner guide plate 43a is fixed to the flange 42 of one nut member 4a, and an outer guide plate 43b is fixed to the flange 42 of the other nut member 4b. The inner guide plate 43a and the outer guide plate 43b are fitted into the guide groove 14 of the base so as to be slidable in the screw axial direction, with their opposing surfaces in slidable surface contact.

[0022] The inner guide plate 43a and the outer guide plate 43b are flat plates that are elongated in the longitudinal direction of the screw shaft 3, and the surface of the inner guide plate 43a facing the inner inner wall surface 15a of the guide groove and the surface of the outer guide plate 43b facing the outer inner wall surface 15b of the guide groove are formed with recessed grooves 46a, 47a and 46b, 47b that slidably fit with the protrusions 16a, 17a and 16b, 17b formed on these inner wall surfaces.

[0023] Furthermore, in the illustrated embodiment, intermediate grooves 48a, 48b parallel to the grooves 46, 47 are provided at the same height on the sliding surfaces of the inner guide plate 43a and the outer guide plate 43b, and a guide key 49 fixed to one of these intermediate grooves is slidably fitted into the other intermediate groove.

[0024] The upper part of the screw shaft 3 is covered with a freely expandable cover 53. The nut members 4a, 4b, which are respectively screwed into the right-hand and left-hand threads of the screw shaft 3, are fixed substantially integrally with the mouthpiece bases 7 by vertical bolts 57. Both ends of the cover 53 are connected to the back surface of the mouthpiece base 7 through slits formed between the center of the bottom surface of the mouthpiece base 7 and the upper surfaces of the nut members 4a, 4b. The mouthpiece 5 having the structure shown in Figures 6 and 8 is attached to the gripping side surface 7s, which is the opposing surface of the mouthpiece base 7.

[0025] As shown in Figures 7 and 8, the upper edge of the gripping side surface 7s of the nozzle base 7 is provided with multiple triangular cross-section ridges 31, each consisting of a perpendicular upper surface 32 and a downwardly inclined surface 33. The triangular cross-section ridges 31 are formed by providing multiple triangular cross-section grooves 35 on the upper edge of the gripping side surface of the nozzle base 7, and the apex ridges of the triangular cross-section ridges 31 do not protrude beyond the gripping side surface 7s of the nozzle base. The apex ridges in the figures are 0.75 mm high, and four ridges are provided at an up-down pitch of 0.75 mm. The width b of the nozzle base 7 is 120 mm.

[0026] Furthermore, the upper edge of the gripping side surface 7s of the nozzle base is provided with a number of U-shaped grooves 36. The U-shaped grooves 36 are 0.75 mm deep grooves machined with a 6φ end mill, and are provided to cut at right angles in plan view the four triangular cross-section protrusions 31 arranged in a vertical width of 3 mm on the upper edge of the gripping side surface of the nozzle base. In other words, the four triangular cross-section protrusions 31 are cut off at right angles by straight line portions 37 on the upper edges of the U-shaped grooves 36.

[0027] The gripping side of the jaw base 7 is provided with screw holes 39 for fixing a jaw of an appropriate shape, and the jaw 5 of the present invention is fixed with a bolt. The gripping surface 5s of the jaw 5 is provided with screw holes 54 for fixing the work receiving plate 38, and the work receiving plate 38 is fixed with a bolt. The jaw 5 and the work receiving plate 38 are fixed in a state where they are placed on the seat plate 8 of the jaw base 7. The jaw 5 is made of metal that is harder than the work w.

[0028] The upper edge of the workpiece gripping surface 5s of the jaw 5 is provided with triangular cross-section ridges 31 and U-shaped grooves 36 of exactly the same structure and number as the triangular cross-section ridges 31 and U-shaped grooves 36 provided on the upper edge of the gripping side surface 7s of the jaw base. The vertical dimension of the receiving plate 38 is set so that the upper surface of the receiving plate 38 is 3 mm lower than the upper edge of the jaw 5, that is, the vertical width of the triangular cross-section ridges 31. The workpiece w shown by the imaginary line is supported by the receiving plate 38 and is gripped and fixed by the apex 34 of the triangular cross-section ridges 31 at a height of 3 mm at its bottom between the jaws 5, 5 which are urged toward each other by the rotation of the screw shaft 3.

[0029] The workpiece w was firmly fixed in place with the apex 34 of the four triangular cross-section ridges 31 and the ends cut by the straight portions 37 of the U-shaped grooves biting into the workpiece w and pressing against the upper surface of the receiving plate 38, providing extremely high support rigidity, particularly for cutting in the Pv and Ph directions of Figures 5 and 6, compared to when the workpiece was held by a jaw with a single flat gripping surface. In an experiment using a jaw with the downward inclined surface 33 of the triangular cross-section ridges 31 at an inclination angle of 30 degrees, the support rigidity of the workpiece decreased, and even when the angle of the downward inclined surface of the triangular cross-section ridge was 45 degrees, sufficient support rigidity could not be obtained when the workpiece was held by only one triangular cross-section ridge.

[0030] For this reason, the number of triangular cross-section ridges 31 is at least two, and preferably three or more, but since gripping the apex of the triangular cross-section ridges can damage the workpiece, it is necessary to remove the gripped portion as necessary, and increasing the number of ridges results in a larger cut-out portion and increased loss of material and cutting time. Therefore, it is considered that the number of triangular cross-section ridges 31 is preferably 2 to 5, and more preferably 3 to 4. In addition, the inclination angle of the downwardly inclined surface of the triangular cross-section ridges 31 is preferably 40 to 50 degrees.

[0031] In the above embodiment, the upper edge of the nozzle base 7 is provided with a triangular cross-section protrusion 31 and a U-shaped groove 36 similar to those on the upper edge of the nozzle 5 in order to enable the nozzle base 7 to directly grip the workpiece even when the nozzle 5 is removed, thereby making it possible to fix large workpieces.

[0032] If necessary when fixing a workpiece with a large width dimension (the vertical dimension in FIG. 2), a support member 51 shown in FIG. 1 can be installed upright in a screw hole 56 provided in the fixing plate 12 to support the bottom surface of the workpiece protruding laterally from the jaws 5. If the bottom surface of the workpiece is flat, the top surface of the support member 51 will be flush with the top surface of the receiving plate 38.

[0033] The work vices proposed in Patent Documents 1 and 2 are small and have high gripping rigidity, and are therefore particularly suitable for mounting the jaws 5 of the present invention. In particular, the vice proposed in Patent Document 2 shown in the embodiment is capable of withstanding a larger vertical force because the upward reaction force acting on the jaw base 7 as a reaction force pressing the workpiece w downward is transmitted to the guide plate 43 fixed integrally to the jaw base 7, and the guide plate 43 is restricted in its vertical movement by the multiple guide strips 16 and 17. In addition, these multiple guide strips 16 and 17 accurately restrict the upward position of the guide plate 43, so that the workpiece can be more firmly fixed at an accurate position, and in particular, the workpiece can be fixed accurately and firmly when the tool moves in the directions indicated by the arrows Pv and Ph in Figures 5 and 6 to machine the workpiece. [Explanation of symbols]

[0034] 5. Base 7 Base 5s grip surface 31 Triangular section ridge 32 above 33 Inclined surface 34 Top edge 36 Groove 38 receiving plate w ワーク

Claims

1. In a jaw used to hold a workpiece by fixing it to the jaw base of a vice, A jaw for a vice is provided with a plurality of triangular cross-section ridges that form an apex with a downwardly inclined surface formed by cutting a plurality of triangular cross-section grooves parallel to the upper edge of a gripping surface that grips a workpiece, and a surface perpendicular to the gripping surface, and a plurality of grooves that cut the ridges at right angles in a plurality of places.

2. 2. The base according to claim 1, comprising 2 to 5 of said triangular cross-section ridges each having a downwardly inclined surface with an inclination angle of 40 to 50 degrees.

3. A base that is fixed to the table of the machine tool; A screw shaft, one side of which in the longitudinal direction is a left-handed screw and the other side is a right-handed screw, and both ends of the screw shaft are rotatably supported on the base in a state in which tension is applied to the screw shaft. A metal base is screwed into the left-hand thread and the right-hand thread 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 an inner wall surface of the guide groove on a side closer to the screw shaft; an outer guide plate that is sandwiched between an inner wall surface of the guide groove on a side farther from the screw shaft and the inner guide plate and is in sliding contact with both of them; A guide strip is provided on the sliding contact surface between the inner wall surface and the guide plate parallel to the screw shaft to regulate 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 of the nozzle bases, and the inner guide plates on both sides of the screw shaft are fixed integrally to the other nozzle base, In a work vice in which an outer guide plate and an inner guide plate move in opposite directions with respect to a base with equal strokes by rotation of a screw shaft, A work vice comprising: a plurality of triangular cross-section ridges having an apex formed by a downwardly inclined surface formed by cutting a plurality of triangular cross-section grooves parallel to the upper edge of the gripping side surface, which is the surface of the jaw base that grips the workpiece, and a surface perpendicular to the gripping side surface; and a plurality of grooves cutting the ridges at right angles at multiple points.

4. 4. The work vice according to claim 3, further comprising 2 to 5 of said triangular cross-section ridges each having a downwardly inclined surface with an inclination angle of 40 to 50 degrees.

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