JP2991944B2 - Machine vise - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machine vise mounted on a table of a machine tool to fix a work, and more particularly to a machine vise capable of fixing a work with high accuracy.

[0002]

2. Description of the Related Art Conventionally, in order to fix a work to be machined on a table of a machine tool or to fix a work on a surface plate in a precision inspection or the like, a small machine vise 1 as shown in FIG. Is used. The machine vise 1 is provided with a fixed frame 4 in which a work holding portion 3 for holding a work 2 is protruded at one end and opposed to the work holding portion 3. A movable holding portion 5 slidable in the direction of holding the work 2 with respect to 4, and a screw rod 6 for pushing the movable holding portion 5 toward the work holding portion 3 are provided. One end of the screw rod 6 is connected to the movable holding section 5, and a portion of the screw rod 6 in the longitudinal direction is connected to a screw rod support section 7 projecting from the other end of the fixed frame 4. It is screwed. Thereby, the movable gripper 5 is displaced toward the work holding portion 3 by rotating the screw rod 6, and the work 2 can be tightened and fixed between the work holding portion 3 and the movable holding portion 5.

[0003]

However, in the machine vise 1 described above, the reaction force of the force for tightening the work 2 is applied to the work holding portion 3 protruding from one end of the fixed frame 4 and to the other end. 9 is received by the threaded bar support 7 projecting from the end of
As shown in (2), the fixed frame 4 is curved as the tightening force of the work 2 is increased. As a result, the work contact surfaces 3a and 5a of the work holding portion 3 and the movable holding portion 5 cannot be kept parallel to each other, so that the lower portion of the work 2 is strongly tightened, but the upper portion of the work 2 cannot be tightened. Would. Further, since the movable holding portion 5 rises from the work placement surface 4a of the fixed frame 4, the work 2 also rises from the work placement surface 4a.

That is, the above-described conventional machine vise 1
Since the fixed frame 4 gradually curves as the force for tightening the work 2 increases, the work 2 cannot be tightened with a uniform tightening force in the vertical direction, or the work 2 rises from the work mounting surface 4a. There is a problem that the work 2 cannot be fixed with high accuracy.

Therefore, an object of the present invention is to solve the problems of the prior art, and even if the force for tightening the work is increased, the fixed frame does not bend, and the work can be tightened and fixed with high accuracy. To provide a machine vise.

[0006]

According to a first aspect of the present invention, there is provided a machine vise comprising: a fixed frame having a work holding portion projecting from one end of a work mounting surface; A movable frame, which is movably mounted on the fixed frame in the direction of clamping the work, and which clamps the work in cooperation with the work clamping portion, and pushes the movable frame toward the work clamping portion. A screw rod to be screwed, a short side portion screwed to the screw rod, and a portion extending from the short side portion to below the work holding portion and extending substantially parallel to the screw bar below the work placement surface. A screw rod support frame having a long side portion. The screw rod support frame may include a support shaft having a middle part in the longitudinal direction of the long side portion and extending in parallel with the work placement surface near the work holding portion and perpendicular to the axis of the screw rod. And the front end of the long side portion abuts against the lower surface of the end of the work holding portion opposite to the movable frame, and the screw rod pushes the movable frame. A bending moment generated in the screw rod support frame by a reaction force of the moving force is input to the work holding portion.

According to another aspect of the present invention, there is provided a machine vise comprising: a fixed frame having a work holding portion projecting from one end of a work mounting surface; A movable frame which is mounted movably in the direction of clamping the work with respect to the work, and which clamps the work in cooperation with the work clamping unit, and a screw rod which pushes the movable frame toward the work clamping unit. A short side portion screwed to the screw bar, and a long side portion extending from the short side portion to below the work holding portion and extending substantially in parallel with the screw bar below the work placement surface. And a screw rod support frame. In the screw rod support frame, the distal end of the long side portion is fixed to the lower surface of the work holding portion, and the screw rod support frame is generated in the screw rod support frame by a reaction force of the pushing force of the movable frame by the screw rod. A bending moment is input to the work holding section.

[0008]

In the machine vise according to the first aspect of the present invention, a reaction force of the work clamping force is input to the screw rod support frame via the screw rod. This reaction force acts as a tensile force on the long side of the screw rod support frame, and the long side is supported by the fixed frame below the work mounting surface of the fixed frame. Thus, the reaction force of the work clamping force acts only as a pulling force acting in a direction substantially parallel to the screw rod below the work mounting surface of the fixed frame, and does not exert a bending moment on this portion. Therefore, the work mounting surface is not curved.
In addition, a bending moment generated by a reaction force of the work clamping force acts on the screw rod support frame. At this time, the long side portion of the screw rod support frame is supported in the middle of the longitudinal direction in the vicinity of the work holding portion of the fixed frame, and its tip abuts on the lower surface of the work holding portion of the fixed frame. I have. As a result, the bending moment generated by the reaction force of the work clamping force is input to the work holding portion of the fixed frame, and is balanced with the bending moment generated in the work holding portion by the work tightening force.
It is possible to prevent the work mounting surface from being curved and the work holding portion from tilting. Therefore, according to the machine vise according to the first aspect of the present invention, even if the force for tightening the work is increased, the work mounting surface is not curved and the work holding portion is not inclined, so that the work can be held with high precision. Can be fixed.

In the machine vise according to the second aspect of the present invention, the distal end of the long side portion of the screw rod support frame is fixed to the fixed frame below the work holding portion of the fixed frame. As a result, the bending moment generated by the screw rod support frame due to the reaction force of the work clamping force is input to the work holding portion, and is balanced with the bending moment generated in the work holding portion by the work tightening force. The work holding portion can be prevented from tilting. Therefore, according to the machine vise according to the second aspect of the present invention, even if the force for tightening the work is increased, the work mounting surface does not curve and the work holding portion does not tilt, so that the work can be held with high precision. Can be fixed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a machine vise according to the present invention will be described below in detail with reference to FIGS. As shown in FIG. 1, a machine vise 100 according to the present embodiment includes a fixed frame 10, a screw rod support frame 20 supported by the fixed frame 10, and a screw rod supported by the screw rod support frame 20. Screw rod 30 mounted on the screw rod 30
, A movable frame 50 pushed by the pushing member 40, and a pushing member 40 pushed by the pushing member 40.
Wedge member 60 interposed between the movable frame 50 and the movable frame 50
And

The fixed frame 10 is shown in FIGS.
As shown in FIG. 1, for example, a bottom wall 11 fixed to a table of a machine tool, a pair of opposed side walls 12 erected on the bottom wall 11, and An upper wall 13 extends in parallel with the bottom wall 11. The upper surface 14 of the upper wall 13 serves as a work mounting surface on which the work W is mounted, and serves as a sliding surface on which the pushing member 40 and the movable frame 50 slide. Also, the pair of side walls 12 and the upper wall 13
The screw rod support frame 20 is incorporated in the inner space 15 defined by the above. Further, as shown in FIG. 1, a work holding portion 16 is provided at the left end of the upper wall 13 in the drawing.

As shown in FIG. 1, the screw rod support frame 20 has an L-shape when viewed from the side.
And the short side portion 21 is the upper wall 1 of the fixed frame 10.
3 and penetrates upward through a through hole 13a provided in the through hole 3. Further, as shown in FIG.
A pair of parallel vertical walls 22 provided at the tip of 1
The screw rod 30 is sandwiched therebetween.

Further, the long side portion 23 of the screw rod support frame 20 has a U-shaped cross section as shown in FIG. 4, and the inner space 15 of the fixed frame 10 as shown in FIG. It is disposed so as to extend substantially in parallel with the screw rod 30. The long side portion 23 is fixed to the fixed frame 1 by the support shaft 80 at a portion in the longitudinal direction.
It is pivoted about 0. That is, as shown in FIG. 4, a pair of opposed side walls 23 of the long side portion 23 are formed.
A pair of mounting holes whose hole axes coincide with each other are penetrated in the a and 23a, and both ends of the support shaft 80 inserted through the pair of mounting holes are fitted into the through holes of the pair of side walls 12 of the fixed frame 10. Is being worn.

On the other hand, the distal end 24 of the long side portion 23 is widened in the lateral direction as shown in FIG. 2, and is located below the work holding portion 16 of the fixed frame 10 as shown in FIG. The lower surface 17 is formed so as to contact the lower surface 17. Also, a top wall 23b forming the long side portion 23
In the upper surface of the fixed frame 10 and in the vicinity of the short side portion 21, a protruding portion 23c which is in contact with the lower surface of the upper wall 13 of the fixed frame 10 is protruded. Thus, the screw rod support frame 20 is supported by the support shaft 80 with respect to the fixed frame 10, but is not rotated around the axis of the support shaft 80 with respect to the fixed frame 10. Have been.

The screw rod 30 is, as shown in FIG.
A screw portion 31 in which a square screw is screwed, a cylindrical tip 32 smaller in diameter than the screw portion 31 provided at the left end of the screw portion 31 in the drawing, and a right end of the screw portion 31 shown in the drawing. And a rear end portion 33 having a hexagonal column shape. Then, as shown in FIG. 2, the nut 34 screwed to the screw portion 31 is formed by a pair of pins 35 extending perpendicularly and horizontally to the axis of the screw rod 30, and a pair of screws 35 of the screw rod support frame 20. It is pivotally supported by the vertical wall 22. On the other hand, a ball joint 37 having a built-in thrust bearing 36 is fitted to the tip 32 of the screw rod 30 as shown in FIG.

As shown in FIGS. 3 and 5, the pushing member 40 is provided with a main body portion 41 having an inverted trapezoidal cross section, and is integrally extended downward from both sides of the main body portion 41 so as to be fixed. The screw rod 30 engaging with the upper wall 13 of the frame 10
And an L-shaped engaging portion 42 as viewed from the axis direction of As a result, the pushing member 40 is moved to the work placement surface 14.
The work can be slid on the work mounting surface 14 without being lifted up. A concave portion 44 is provided on the back surface 43 of the main body portion 41 so as to be spherically fitted with the ball joint 37 provided at the tip of the screw rod 30.
After the ball joint 37 is fitted into the recess 44 and the fixing plate 45 is screwed onto the back surface 43 to prevent the ball joint 37 from coming off, the pushing member 40 and the screw bar 30 are relatively swung. It can be movably connected. On the other hand, as shown in FIG. 3, the front surface 46 of the main body portion 41 opposite to the screw rod 30 has a gradient approaching the work holding portion 16 of the fixed frame 10 as the distance from the work mounting surface 14 increases. A given inclined surface 46 is provided. The inclined surface 46 and the wedge member 6
0 is in surface contact. As shown in FIGS. 2 and 3, the pushing member 40 includes a screw member 47 screwed to the side wall 50 a of the movable frame 50.
Is engaged. Thus, when the pushing member 40 is displaced toward the nut 34 by the screw rod 30, the movable frame 50 moves integrally with the pushing member 40.

The movable frame 50 is provided on the work mounting surface 1.
4, a rectangular parallelepiped block slidable on the inside thereof is formed with a concave groove 51 for receiving the screw rod 30 and an internal space 52 for receiving the pushing member 40 as shown in FIG. 2. I have. The movable frame 50 has a thick front end wall 53, and a lower surface 54 of the front end wall 53 facing the work mounting surface 14 is provided with a pair of spaced apart predetermined spaces as shown in FIG. A receiving hole 55 is formed. And
In the receiving hole 55, a coil spring 57 and a cylindrical pin 5 are provided.
6 is slidably inserted, and the cylindrical pin 56 is urged by the spring force of the coil spring 57 so as to protrude from the lower surface 54 toward the work mounting surface 14. Also,
As shown in FIG. 2, a pair of receiving holes 55 are formed in the lower surface of the central portion in the longitudinal direction of the movable frame 50 so as to sandwich the screw rod 30, and a columnar pin 56 and a coil spring 57 are formed. It is inserted. And the cylindrical pin 5
6 is urged by the spring force of the coil spring 57 so as to protrude from the lower surface 54 toward the work mounting surface 14. As a result, the movable frame 50 is
When it is not pressed by 0, it floats parallel to the work mounting surface 14 as shown in FIG. However, as shown in FIG.
Since the locking plate 53d that engages with the upper wall 13 is screwed with the bolt 53e, the movable frame 50 is configured to float by a predetermined dimension with respect to the work mounting surface 14.

As shown in FIG. 3, the wedge member 60 is a columnar member having a substantially trapezoidal cross section, which is attached to a side surface 53a of the front end wall 53 of the movable frame 50 on the pushing member 40 side. It has been. And the front 6
1 is in close contact with the inner side surface 53a of the front end wall 53, and its lower surface 62 is flush with the lower surface 54 of the front end wall 53. Further, the wedge member 60 is engaged with a step-like convex portion 53b provided at a lower portion of the front end wall 53, and is displaced downward integrally with the front end wall 53. The rear surface 63 of the wedge member 60 is formed as an inclined surface, and can be in close contact with the inclined surface 46 of the pushing member 40.

At this time, as shown in FIG. 3, the front surface 46 of the pushing member 40 and the rear surface 63 of the wedge member 60 move upward from the work placement surface 14 as shown in FIG.
The workpiece holding surface 16 is inclined so as to approach the workpiece holding portion 16 and extends inclining with respect to the workpiece mounting surface 14. Therefore, the pushing member 40 is moved to the wedge member 6.
A part of the pressing force for pressing 0 is converted into a force for pressing the wedge member 60 against the work mounting surface 14. As described above, since the wedge member 60 is engaged with the front end wall 53 of the movable frame 50 so as to be displaced downward integrally, when the wedge member 60 is pressed against the work mounting surface 14. , The movable frame 50 is a movable frame 50
Is pressed against the work mounting surface 14 against the urging force of the spring 57 that floats from the work mounting surface 14.

As shown in FIG. 1, an insertion hole 58 through which the screw rod 30 is inserted is formed at the rear end of the movable frame 50, and a bush 70 is coaxial with the insertion hole 58.
Is attached. The bush 70 includes a concentric outer ring 71 and an inner ring 72, and a bush rubber 73 interposed therebetween. And
The outer ring 71 is fixed to an end of the movable frame 50, and the inner ring 72 is slidable in the axial direction on a cylindrical portion 33 a provided adjacent to the rear end 33 of the screw rod 30. It is inserted so as to be relatively rotatable in the circumferential direction. This prevents a metal piece or the like generated when machining the work from entering the inside of the machine vise 100 from the gap between the insertion hole 58 and the screw rod 30. In addition, since the bush rubber 73 is bent,
For example, the movable frame 50 rises from the work mounting surface 14, or the screw rod support frame 20 bends and the screw rod 30
Is inclined, the relative displacement between the outer ring 71 and the inner ring 72 can be absorbed.

Next, the operation of the machine vise 100 of the present embodiment configured as described above will be described. First, when the work is not held, the movable frame 50 is slightly lifted from the work mounting surface 14 by the spring force of the coil spring 57, as shown in FIG. Thereby, the work contact plate 59 attached to the front surface of the front end wall 53 is also slightly separated from the work mounting surface 14. In this state, place the work on the work
4, and a handle (not shown) is attached to the rear end 33 of the screw rod 30 and the screw rod is rotated.
0 pushes the pushing member 40 toward the work holding portion 16. When the inclined surface 46 of the pushing member 40 comes into contact with the inclined surface 63 of the wedge member 60, the wedge member 60 and the movable frame 50 are displaced integrally with the pushing member 40 in the direction of clamping the work, and The contact plate 59 contacts the work.

When the screw rod 30 is further rotated to press the work toward the work holding portion 16, the inclined surface 46 of the pushing member 40 and the inclined surface 63 of the wedge member 60 are strongly pressed against each other. Then, part of the pressing force by which the pressing member 40 pushes the wedge member 60 toward the work holding portion 16 causes the wedge member 60 to move the wedge member 60 between the inclined surfaces 46 and 63 to the work mounting surface 14. It is converted into the force to push toward. At this time, the pushing member 40 engages with the upper wall 13 of the fixed frame 10 forming the work mounting surface 14 and cannot be lifted from the work mounting surface 14, so that both the wedge member 60 and the movable frame 50 Mounting surface 1
Pressed toward 4. Therefore, as shown in FIG. 6, the work W is pressed toward the work placement surface 14 by frictional contact with the contact plate 59, and is tightened and fixed while being in close contact with the work placement surface 14.

That is, the machine vise 100 of the present embodiment
Is that the work W is pressed against the work placement surface 14 to be in close contact with the work placement surface 14, and is fastened and fixed by the work holding portion 16 of the fixed frame 10 and the front end wall 53 of the movable frame 50. The work W can be tightened and fixed without being lifted from the work mounting surface 14.

By the way, as shown in FIG.
The reaction force F of the force that clamps and clamps the work W acts on the short side portion 21 of the screw rod support frame 20 via the nut 34 screwed into the screw rod 30. The reaction force F acts as a tensile force on the long side portion 23 of the screw rod support frame 20. As described above, the long side portion 23 is supported by the support shaft 80.
Are supported by the fixed frame 10. As a result, the tensile force acting on the long side portion 23 acts as a tensile force acting on the side wall 12 of the fixed frame 10 in a direction substantially parallel to the screw rod 30, but does not act on the bending moment. . Therefore, in the machine vise 100 of the present embodiment, the reaction force F of the force for tightening the work W does not act on the upper wall 13 of the fixed frame 10 forming the work mounting surface 14, and thus the work mounting surface 14
Does not bend.

The axis of the screw rod 30 is located away from the axis of the support shaft 80 that supports the screw rod support frame 20 to the fixed frame 10. As a result, the bending moment M generated by the reaction force F of the work clamping force acting on the screw rod 30 acts on the screw rod support frame 20 as a clockwise bending moment with respect to the axis of the support shaft 80.
However, as described above, the screw rod support frame 20
The tip 24 of the long side portion 23 is the lower surface 1 of the work holding portion 16.
7 abuts on the screw rod support frame 20.
Does not rotate around the support shaft 80, but merely causes the long side portion 23 of the screw rod support frame 20 to bend.

At the same time, a bending moment M generated by the reaction force F of the work clamping force acting on the work holding portion 16 is applied to the work holding portion 16 as a counterclockwise bending moment with respect to the axis of the support shaft 80 in the drawing. Works. The illustrated counterclockwise bending moment acting on the work holding portion 16 and the illustrated clockwise bending moment acting on the screw rod support frame 20 are determined by the work holding portion 16 and the screw rod support frame 20 being moved by the work holding portion. 16 lower surface 17
Are balanced by contact with each other. Therefore, in the machine vise 100 of the present embodiment, it is possible to prevent the work mounting surface 14 from being curved and the work holding portion 16 from tilting due to the reaction force of the work clamping force.

That is, the machine vise 100 of this embodiment
According to this, it is possible to prevent the work mounting surface 14 from being curved and the work holding portion 16 from being inclined by the reaction force F of the force for tightening the work or the bending moment M generated by the reaction force F. In addition, since the work W can be tightened and fixed while pressing the work W against the work mounting surface 14, the work W does not float up from the work mounting surface 14. Therefore, according to the machine vise 100 of the present embodiment, the work can be fixed with high accuracy.

The machine vise of the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications are possible based on the gist of the present invention. For example, as shown in FIG. 7, the distal end 24 of the long side portion 23 of the screw rod support frame 20 may be tightly attached to the lower surface 17 of the work holding portion 16 of the fixed frame 10 and screwed with the bolt 90. Not only can the same effect as the above-described machine vise be obtained, but also it can be easily manufactured.

Although the wedge member 60 is interposed between the movable frame 50 and the pushing member 40 in the above-described embodiment, the inclined surface 6 is provided on the front end wall 53 of the movable frame 50.
3 can be integrally formed, the wedge member 6
0 can be eliminated. Further, without using a wedge effect acting between the inclined surface 46 of the pushing member 40 and the inclined surface 63 of the wedge member 60, for example, the pushing member 40 is moved to a predetermined position with respect to the front end wall 53 of the movable frame 50. It is easy for a specialist in this field to use a link mechanism that displaces the movable frame 50 toward the work mounting surface 14 when approaching a distance or more. In the above-described embodiment, the movable frame 50 is mounted on the work mounting surface 14.
There is provided an urging means for floating the movable frame 50 so that the urging force of the urging means is lost when the pushing member 40 is displaced relative to the movable frame 50, for example. It may be made to approach the surface 14.

[0030]

Since the machine vise of the present invention is constructed as described above, the work mounting surface does not deform due to the reaction force of the work clamping force. Further, since the bending moment generated in the work holding portion by the reaction force of the work clamping force and the bending moment generated in the screw rod support frame are balanced, the work mounting surface is not curved and the work holding portion does not tilt. Therefore, according to the machine vise of the present invention, the work can be pinched and fixed with high accuracy.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of one embodiment of a machine vise according to the present invention.

FIG. 2 is a plan view showing a main part of the machine vise shown in FIG.

FIG. 3 is an enlarged longitudinal sectional view showing a main part of the machine vise shown in FIG. 1;

FIG. 4 is a sectional view taken along the line IV-IV shown in FIG. 1;

FIG. 5 is a sectional view taken along the line VV shown in FIG. 1;

FIG. 6 is a longitudinal sectional view for explaining the operation of the machine vise shown in FIG.

FIG. 7 is a longitudinal sectional view of another embodiment of the machine vise according to the present invention.

FIG. 8 is an overall side view schematically showing a conventional machine vise.

FIG. 9 is an overall side view schematically showing a problem of a conventional machine vise.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Fixed frame 20 Screw bar support frame 30 Screw bar 40 Pushing member 50 Movable frame 60 Wedge member 70 Bush 80 Support shaft 90 Bolt 100, 200 Machine vise of the present invention

Claims (2)

(57) [Claims] A fixed frame having a work holding portion projecting from one end of a work mounting surface; and a work holding portion mounted on the fixed frame so as to be movable in a direction for holding the work. A movable frame for moving and holding the work, a screw rod for pushing the movable frame toward the work holding portion, a short side portion screwed to the screw rod, and the work holding portion from the short side portion. A screw rod support frame having a long side portion extending to below the work mounting surface and extending substantially in parallel with the screw bar, wherein the screw bar support frame has a longitudinal length of the long side portion. A part in the middle in the direction is supported by the fixed frame by a support shaft extending in parallel with the work mounting surface and perpendicular to the axis of the screw rod in the vicinity of the work holding portion, and the long side The tip of the minute abuts against the lower surface of the end of the work holding portion opposite to the movable frame, and the bending generated on the screw rod supporting frame by the reaction force of the screw rod pushing the movable frame. A machine vise wherein a moment is input to the work holding section. 2. A fixed frame having a work holding portion projecting from one end of a work mounting surface, and a work holding portion mounted to the fixed frame so as to be movable in a direction for holding the work. A movable frame for moving and holding the work, a screw rod for pushing the movable frame toward the work holding portion, a short side portion screwed to the screw rod, and the work holding portion from the short side portion. A screw rod support frame having a long side portion extending to below the work mounting surface and extending substantially in parallel with the screw bar, wherein the screw bar support frame has a tip end of the long side portion. Is fixed to the lower surface of the work holding portion, and inputs a bending moment generated in the screw rod support frame to the work holding portion by the reaction force of the screw rod pushing the movable frame. Machine vise to butterflies.