JP4064014B2 - Base - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a base provided in a vise for holding a workpiece or a portion of a jig that is used for positioning or fixing of a workpiece to be in contact with the workpiece.
[0002]
[Prior art]
A base is provided at a portion of the vice or jig that contacts the workpiece. A workpiece fixed for processing or position holding is clamped by a base or positioned in contact with the base.
[0003]
The base is fixed or movable to the vise or jig body. The base attached at a fixed position receives and holds the workpiece that advances toward this, and the base that is provided so as to move is advanced toward the workpiece by a pressure device such as a screw or a cylinder. Hold. When it is necessary to hold the workpiece firmly, a pressure device that generates a powerful force is provided, and the base is brought into contact with the workpiece with a large force. At this time, a large reaction force acts on the base from the workpiece.
[0004]
The base provided so as to be movable has a gap when the sliding part or the rolling part is large, and even if it does not have a gap, a sufficient tightening allowance cannot be provided, so that the rigidity is lowered. The reaction force acting on the base from the workpiece is transmitted to the vise and jig body through this sliding part or rolling part. Therefore, when the base is pressed against the work with a large force, the reaction force causes the base to move. Happens to be biased. This deviation often occurs due to rattling or deformation of the sliding portion or rolling portion described above, but can also occur due to elastic deformation of the vise or the jig body.
[0005]
In a vise used to fix a workpiece to a machine tool, the accuracy of the workpiece fixing position directly affects the workpiece machining accuracy. In particular, when performing micron-order machining, it is assumed that the workpiece is fixed with a corresponding accuracy.
[0006]
Considering a simple example of fixing a work by holding the side of the work with a base of a vise attached to a work table of a machine tool, the base of the vise protrudes upward from the main body of the vise, and thus the base can be moved. The sliding part or the rolling part for making is usually located behind the base (on the side opposite to the workpiece) and below the center of the base. When the work is sandwiched between the vices having such a structure, a moment in the direction in which the base is directed upward is generated due to the reaction force from the work, and the base provided movably has a backlash of the sliding part or the rolling part. Due to the deformation, it moves up on the order of several microns.
[0007]
Since the work is sandwiched between the vise bases, when the base moves up, the work inevitably moves up. For example, when processing the upper surface of the work, the upward movement of the base becomes a processing error. Further, the reaction force from the work causes the base and the vice body itself to elastically deform, and these deformations also cause an error in the same direction. This tendency is particularly likely to occur when a thin work is sandwiched between the upper portions of the base.
[0008]
Further, when the side surface of the workpiece is sandwiched between the bases of the vice, if the side surface is not machined to a correct plane and angle, one-side contact occurs between the workpiece and the base. For example, when a workpiece having a cross-section of an inverted trapezoid is sandwiched, the workpiece is sandwiched by the upper edge of the base, and as with the case of sandwiching the thin workpiece, a large moment is generated to try to face the base upward, For example, the base moves up and a gap is generated between the bottom surface of the workpiece and the mounting surface.
[0009]
In many cases, machining is performed without recognizing such a phenomenon that occurs when a workpiece is held by a vice. In such a case, an unexpected large machining error occurs.
[0010]
[Problems to be solved by the invention]
In order to prevent the above-described processing errors from occurring, it is only necessary to generate a force in a direction in which the workpiece is pressed against the mounting surface when the side surface of the workpiece is sandwiched between vise bases. Further, for example, when the side surface of the workpiece is inclined, the surface of the base that contacts the workpiece may be tilted in accordance with the inclination of the workpiece.
[0011]
SUMMARY OF THE INVENTION An object of the present invention is to obtain a base having a simple structure having the above-described functions, and therefore easy to maintain and can be provided at low cost. It is an object of the present invention to obtain a technical means for realizing a base that generates a force in a direction orthogonal to the urging direction of the head and a base that can tilt a surface that contacts the work in accordance with the surface accuracy of the work.
[0012]
[Means for Solving the Problems]
In the invention of this application, pressure is applied to the workpiece via the spherical groups 55 and 56 arranged in two planes substantially parallel to the plane abutting on the workpiece of the base so that the line segment connecting the centers draws a zigzag. The above-mentioned problem is solved by providing the contact member 53 to be used. The zigzag shape of the line segment connecting the centers of the spheres may include those formed in a plane parallel to the work contact surface of the base, but if a zigzag shape that does not exist in the plane is not necessarily included Don't be. Wherein the center of the sphere to be present in the two planes, by connecting alternately to those present in those and the other surface which is present on one side, the shape of the zigzag of the line segment is drawn.
[0013]
A structure in which spheres distributed in two planes are in contact with each other on all line segments drawing a zigzag and a sphere in contact with each other only on a line segment inclined in one direction and the other direction A structure in which the spheres are separated from each other is possible on the line segment inclined in the direction. The former structure can be employed as a means for imparting to the die a function of changing the direction of the pressure applied to the workpiece, or as a means for allowing the surface of the die that contacts the workpiece to be tilted. On the other hand, the latter structure can be employed as a means for generating a thrust force in one direction substantially perpendicular to the pressing direction of the die on the surface of the die that contacts the workpiece. That is, with the latter structure, it is possible to realize a base that prevents the workpiece from being lifted by pressing the bottom surface of the workpiece against the workpiece placement surface when the side surface of the workpiece is clamped.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a view showing a first embodiment of the present invention, 51 is a fixing member, 52 is a pressing device such as a screw (not shown), a pressing member pushed in the right direction in the drawing, and 53 is a workpiece (not shown). It is a contact member provided with the upward contact surface 53a which contacts the bottom face. Reference numeral 54 denotes a spherical housing space formed by the fixing member 51, the pressing member 52, and the contact member 53 . As shown in FIG. 2, the spherical housing space 54 is formed by a U-shaped concave groove formed in the fixing member 51 and the contact member 53. 55 is a first group of spheres contained in the accommodation space 54 , 56 is a second group of spheres, and the first group of spheres 55 is distributed on the first surface A above the accommodation space 54. The second group of spheres 56 are distributed on the second surface B located below. The first surface A and the second surface B are parallel to the contact surface 53a of the contact member.
[0015]
The first group of spheres 55 distributed on the first plane A and the second group of spheres 56 distributed on the second plane B have a gap between adjacent spheres. The first group of spheres 55 and the second group of spheres 56 are distributed so as to have a staggered positional relationship with each other. Therefore, the sphere 55 of the first group and the spherical body 56 of the second group, as shown in FIG. 2 (a), if it is contained in the respective one row spherical housing space 54 formed by the concave groove , sphere 55 of the first group is in contact with the two second groups of spheres, and as shown in FIG. 2 (b), the first group in the sphere receiving space 54 formed by the groove sphere 55 is housed in the one row, when the second group of the spherical body 56 is housed in the two rows, sphere 55 of the first group, 3 to contact the spherical body of the four second group It is. A line segment connecting the centers of the first group of spheres 55 and the second group of spheres 56 adjacent to each other forms a zigzag.
[0016]
In the first embodiment, when the pressing member 52 advances to the right in the figure, the contact member 53 moves upward and is pressed against the bottom surface of the workpiece. At this time, even if the bottom surface of the workpiece is slightly inclined, the contact member 53 tilts and moves up following the bottom surface of the workpiece.
[0017]
FIG. 3 is a diagram showing a second embodiment of the present invention. In the second embodiment, the pressure member 52 is pushed toward the back surface of the contact member 53, and the spherical housing space formed between the back surface of the contact member 53 and the front surface of the pressure member 52. 54 is provided. The accommodating space in the rear surface of the front and the contact member 53 of the biasing member 52, and thus formed to form a groove of a shallow U-shaped cross section. In the accommodation space 54, a first group of spheres 55 and a second group of spheres 56 are accommodated in the same manner as in FIG.
[0018]
In this embodiment, when the pressing member 52 is moved to the workpiece side and the contact member 53 comes into contact with the workpiece, the contact member 53 can tilt following the inclination of the surface of the workpiece. Therefore, by using the structure of the second embodiment for the base of the vice, the work clamping surface of the base is tilted following the surface of the work, and the function of preventing the workpiece and the base from being struck is provided.
[0019]
FIG. 4 shows a third embodiment of the present invention. In the third embodiment, as in the second embodiment, in the groove provided on the back of the groove and the contact member 53 provided on the front surface of the biasing member 52, a sphere accommodating space 54 is formed, pressure applying The member 52 is pushed toward the back surface of the contact member 53.
[0020]
A first group of spheres 55 and a second group of spheres 56 are housed in the housing space 54 in a distributed manner on surfaces A and B parallel to the contact surfaces 53a of the contact members, respectively. Spacers 57 made of small-diameter spheres are provided to prevent movement in the respective surfaces A and B of the spheres 55 and 56. The contact member 53 is urged upward by an urging spring 60, and the urging force causes the first group of spheres 55 to contact only the second group of spheres 56 adjacent thereto. That is, the first group of spheres 55 has a clearance E between the second group of spheres 56 adjacent to the lower side.
[0021]
In this structure, when the pressing member 52 moves toward the workpiece and the contact member 53 contacts the workpiece, the second group of spheres 56 faces the first group of spheres 55 downward due to the additional pressing force of the pressing member 52. As a result, the contact member 53 is urged downward to press the abutted workpiece against its placement surface, thereby preventing the workpiece from being lifted.
[0022]
5 to 8 show specific examples in which the structure of the third embodiment is adopted for a work vise base. Although the vise 58 includes the movable base 15 and the fixed base 14, since it has the same structure, only the movable base will be described below.
[0023]
The pressure member 52 is fixed to the moving base 6 screwed to the vise feed screw 16, and due to the large axial force generated at the stroke end due to the rotation of the feed screw 16 and the action of the booster mechanism 59, It is moved and pressured to the fixed base 14 side. A rectangular recess is formed in the center of the work clamping surface 62 of the base 15, and a plate-like contact member 53 is fitted into the recess so as to be slightly movable in at least the vertical direction. On the bottom surface of the rectangular recess and the back surface of the contact member 53, two concave grooves having a U-shaped cross section in the vertical direction are formed at opposite positions, and two spherical housing spaces 54 are formed by the opposed concave grooves. Has been. In the two housing spaces, the first group of spheres 55 and the second group of spheres 56 are housed in the same form as described in FIG.
[0024]
A spring accommodating space that opens to the lower side is formed in the lower side portion of the contact member 53, and an urging spring 60 such as a coil spring, urethane resin, or disc spring is accommodated in the spring accommodating space, and between the lower side of the recess. By applying an urging force, the contact member 53 is urged upward. A stopper bolt 61 extending toward the pressing member 52 side is planted in the center of the back surface of the contact member 53, and the position where the contact surface 53a of the contact member 53 slightly protrudes from the work clamping surface 62 of the base by the stopper bolt. It is locked with. That is, when the contact member 53 is urged upward by the urging force of the urging spring 60, the contact member 53 is brought into contact with the workpiece by the contact between the first group of spheres 55 and the second group of spheres 56 located above the first group of spheres 55. Since it is biased in the direction protruding from the clamping surface 62, the amount of protrusion is defined by the stopper bolt 61.
[0025]
The structure of the portion other than the vise base shown in FIG. 4 is as follows. The movable table 3 is movable in the left-right direction in the drawing along the slide base 1 and is fixed to one of the semicircular knock holes 17 provided in the slide base 1 at a predetermined interval by the knock pin 2. A cylindrical cylinder housing 18 is fitted to the movable base 3 so as to be rotatable and non-movable in the axial direction. A cylinder 4 of a booster mechanism is formed on the inner peripheral surface of the cylinder housing 18 and is operated. The screw 5 is screwed into the cylinder housing 18.
[0026]
A cylindrical portion 19 is provided between the operation screw 5 and the pushing member 8 at the tip, and a ball clutch 20 is mounted on the cylindrical portion. The ball 22 of the ball clutch urged in the outer peripheral direction by the spring 21 is fitted into a recess 23 provided in the cylinder housing 18 at the retracted position of the pushing member 8, so that the rotation of the operation screw 5 is performed in the cylinder housing 18. To be communicated to. Reference numerals 24 and 25 are thrust plates for fixing the axial movement of the cylinder housing 18, 26 is a flange of the cylinder housing, and 27 is a nut.
[0027]
The end of the cylinder housing 18 on the movable base side is connected to a feed screw 16 disposed on the same axis via a rotary joint 28. The rotary joint 28 allows the cylinder housing 18 and the feed screw 16 to be relatively unrotatable and slightly movable in the axial direction, and urges the feed screw 16 toward the cylinder housing 18 by the elastic ring 12. It is connected. Specifically, a diametrical groove is provided in the end face of the cylinder housing 18 having the outer flange 29 on the feed screw 16 side, and a diametrical projection 33 of the feed screw 16 having the outer flange 30 at both ends in this groove. Is fitted, and the elastic ring 12 is fitted between the outer flanges 29 and 30.
[0028]
A ring-shaped ram 7 is formed at the base end (left end in the figure) of the feed screw 16, and this ram is fitted into the cylinder 4 formed in the cylinder housing 18 so as to be axially movable. A stopper screw 32 in which a spherical body 31 is fitted to the contact end is screwed onto the shaft center of the feed screw 16. The feed screw 16 is hollow. A tool is inserted into the center hole of the feed screw 16 and the stopper screw 32 is rotated to adjust the position of the stopper (sphere) 31.
[0029]
In the cylinder 4, passive spheres 10 a and 10 b made of two rows of steel balls are arranged in the axial direction at positions that equally divide the circumference, and the positions in the circumferential direction are the same as those of the passive spheres or The pushing spheres 11 are arranged in a staggered manner.
[0030]
The pushing sphere 11 is arranged on a pitch circle having a larger diameter than the passive spheres 10a and 10b and a smaller diameter than the distribution pitch circle of the passive spheres 10a and 10b. The pushing sphere 11 is urged toward the inner diameter side of the cylinder 4 by the spring force of the elastic ring 12, and is in contact with the conical surface 8 e of the pushing member 8.
[0031]
In the above configuration, when the operation screw 5 is rotated, the cylinder housing 18 and the feed screw 16 are rotated together through the ball clutch 20 and the rotary joint 28, and the threaded portion between the feed screw 16 and the movable base 6 is engaged. Due to the screw action, the movable base 15 advances and retreats.
[0032]
When the movable base 15 advances and comes into contact with the workpiece, the movement of the movable table 6 stops and the rotational load of the feed screw 16 increases. When the operation screw 5 is further rotated in this state, the ball clutch 20 cannot resist the load, the ball 22 is detached from the recess 23, the rotation of the cylinder housing 18 is stopped, and only the operation screw 5 is rotated. Become. Then, the pushing member 8 at the tip of the operation screw 5 moves forward with respect to the cylinder housing 18 and pushes the pushing sphere 11 radially outward, so that the pushing sphere 11 enters between the two passive spheres 10a and 10b. Then, the passive sphere 10b on the moving base 6 side pushes the end surface of the ram 7 and pushes the feed screw 16 in the right direction in the figure, which is transmitted to the movable base 15 to clamp the workpiece.
[0033]
The pushing member 8 provided integrally with the distal end portion of the operation screw 5 advances while rotating around the central axis of the cylinder 4. The rotation of the pushing member 8 rotates the pushing sphere 11 and further rotates the passive sphere 10. By this rotation, the push-in sphere 11 is pushed in such a way that the contact point of both the passive spheres 10 makes a rolling contact and draws a spiral, and the generation of a large frictional force due to the sliding contact is avoided. By inserting a freely rotatable sleeve into the inner circumference of the cylinder 4 and mounting a freely rotatable thrust plate on the fixed end face of the cylinder and the end face of the ram 7, the rolling contact in the circumferential direction can be made more complete. can do.
[0034]
The maximum tightening force is exerted at a position where the tip of the pushing member 8 is in contact with the stopper (sphere) 31. In this state, the elastic ring 12 of the rotary joint 28 is elastically crushed.
[0035]
When the operating screw 5 is reversely rotated from this fastened state, the pushing member 8 is retracted, the clamping force of the elastic ring 12 is released, and the feed screw 16, that is, the ram 7 moves to the left in the drawing, and the pushing ball 11 Is pushed inward in the radial direction, and the fastening force of the movable base 15 is released. When the operation screw 5 is further retracted, the ball 22 of the ball clutch 20 is fitted into the recess 23 so that the rotation of the operation screw 5 is transmitted to the cylinder housing 18 and the feed screw 16, and thereafter the feed screw 16. Rotation of the movable table 6 moves backward.
[0036]
That is, when a work to be sandwiched between the fixed base 14 and the movable base 15 is placed and the operation screw 5 is rotated, the pressure member 52 is first sent by the rotation of the feed screw 16 to fix the work. It is sandwiched between the base and the movable base. When the operation screw 5 is further rotated, the clutch 20 is disengaged and the booster mechanism 59 starts operating, and the workpiece is firmly clamped between the fixed base 14 and the movable base 15. At this time, the contact surface 53a of the contact member 53 comes into contact with the workpiece before the workpiece clamping surface 62, and is pushed in until the contact surface 53a of the contact member is flush with the workpiece clamping surface 62 by the reaction force acting from the workpiece. Be turned. By the downward movement of the contact member 53 at this time, the work is pressed against the work placing surface 63 of the vice and then sandwiched. This operation completely prevents the workpiece from being lifted when it is clamped by a vice, and realizes the accuracy of the workpiece upper surface when holding the workpiece on the order of 1 micron, which was impossible with a conventional vice. be able to.
[Brief description of the drawings]
1 is a schematic cross-sectional side view showing a first embodiment. FIG. 2 is a cross-sectional view taken along a line CC in FIG. 1. FIG. 3 is a schematic cross-sectional side view showing a tilted state of the second embodiment. 4] Schematic cross-sectional side view showing the third embodiment [FIG. 5] Partial cross-sectional side view showing a specific example of the vise provided with the base of the present invention [FIG. 6] Front view of the base of the vice of FIG. Figure 7 is a cross-sectional plan view of the die of the device of FIG. 4 and FIG. 8 is a detailed view of the device of the booster mechanism of Figure 5 dESCRIPTION oF REFERENCE nUMERALS
52 Pressure member
53 Contact member
53a Contact surface
54 Sphere containing space
60 Biasing spring
61 Stopper bolt A First side B Second side

Claims (3)

A pressure member (52) connected to the pressure device, a contact surface (53a) provided with a contact surface (53a) that contacts the workpiece, and provided so as to be relatively tiltable with respect to the pressure member; A spherical housing space (54) formed by a concave groove between the member and the contact member; a first surface (A) and a second surface (B) substantially parallel to the contact surface in the housing space ; only the two sides and a sphere are distributed, spheres of the first group are distributed on the first surface (55) and a second of the second group are distributed on the surface sphere (56) are distributed in a row each sphere a first group adjacent and the second group of balls are distributed as a line segment connecting their centers to form a zigzag, with member (52) work when the contact member to move to the side (53) is in contact with the workpiece, the contact member (53), characterized in that the tilting following the inclined surface of the workpiece, die. Urging member connected to the pressure applying apparatus (52), a contact surface for contact with the workpiece contact member provided so as to be relatively tilted with respect to the urging member comprises a (53a) (53), pressure applying A spherical housing space (54) formed by a concave groove between the member and the contact member; a first surface (A) and a second surface (B) substantially parallel to the contact surface in the housing space ; The first group of spheres (55) distributed on the first surface are distributed in one row and the second surface is distributed on the second surface. The two groups of spheres (56) are distributed in two rows, and the adjacent first group of spheres and the second group of spheres are distributed so that the line segment connecting their centers forms a zigzag, A base, wherein when the pressing member (52) is moved to the workpiece side and the contact member (53) contacts the workpiece, the contact member (53) tilts following the inclination of the surface of the workpiece . The spheres of the first group and the spheres of the second group are in contact with each other only on the line segments facing in the same direction among the line segments forming the zigzag, and the spheres of the first group are only on the line segments in the direction. The urging member (60) for urging the contact member (53) substantially parallel to the contact surface (53a) so as to contact the second group of spheres is provided. Or the base of 2 .

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