JPH04176531A - Holding jig for work and using method thereof - Google Patents

Abstract

PURPOSE:To keep a work in a correct centering state, by equipping a centering projection bar which suspends with its overhang from the lower face of a barrel type block main body, and fixing the centering projection bar to a key groove which opens for the work table of a machine tool so as to be fitted with its insertion from the upper part. CONSTITUTION:A block main body 11 is equipped with a flat lower face 11a in a constant width slightly smaller than the diameter dimension of the round bar thereof, also it holds the work 12 thereof with good stability, as the pad which linearly contacts with the circumferential face of the work 12 at the upper face 11b thereof made in a circular convex shape. Also, the centering projection bar 13 which suspends with its overhang integrally in continuation from the eccentric position of the flat lower face 11a in the block main body 11 is formed in a high accuracy, as the relation that the sectional shape and size thereof can be correctly engaged with the open upper part of a section inverted T type key groove 14 which opens for the work table T of a machine tool. Eventually, the work 12 holds in a centering state of itself, by engaging with the key groove 4 of the work table T, with the centering projection bar 13 as the key.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to milling machines, machining centers, and other machine tools when performing various precise processing such as drilling, grooving, scribing, and measuring on a workpiece. This invention relates to a jig that automatically holds a workpiece in an accurate centering state on a processing table of a machine tool, and a method of using the jig.

<Prior Art> As a jig for holding a workpiece on a processing table of a machine tool, a ■7 block has been generally used.

In other words, as is clear from FIG. 17, which shows a typical example, in preparation for machining the workpiece (1), the machine tool is equipped with a holding block (2) and a step block (3). The threaded support (6) is placed vertically in a fixed state from the key groove (5) opening in a vertical T-shape on the cross section of the processing table (4), and the V Block (2) and step block (3)
The workpiece (1) and - At the same time, the holding block (2) is positioned and fixed onto the processing table (4).

<Problem to be solved by the invention> However, in the holding means for the workpiece (1) using such a V block (2) as a jig, there is a V-shaped notch cut out on the top surface of the block (2). Since the expansion angle (θ) is fixed in advance, if the thickness of the workpiece (1) is extremely thick, it may not be possible to position and hold the workpiece (1) in its centered state. It is necessary to prepare a large number of blocks (2) of various types according to the taste of the workpiece (1), and use them to attach/detach/replace them. This means that it cannot be used universally for various workpieces (1). -Also,■
Since the bottom surface of block (2) is a flat surface,
It is temporary to position and fix the block (2) to the processing table (4) together with the workpiece (1), so every time the workpiece (1) is attached or removed, the block (2) is aligned with the workpiece (1). The process must be readjusted one by one, which is extremely complicated, resulting in a decrease in work efficiency and an increase in processing costs. This problem cannot be fundamentally improved even if magnetic force is applied to the upper and lower surfaces of the block (2).

<Means for Solving the Problems> The present invention is intended to solve these problems, and as a holding jig for a workpiece that is useful for this purpose, a metal round bar material is machined to have a cross-sectional shape larger than a semicircle. It is equipped with a semi-cylindrical block body of a certain length, and a centering protrusion that extends continuously and hangs down from an eccentric position on the flat bottom surface of the block body, and the centering protrusion is opened to the processing table of a machine tool. The first feature is that it is designed to be inserted and fitted into the vertical T-shaped key groove from above, and the cross-sectional shape is larger than a semicircle from the gold 2 round bar material. A semi-cylindrical block body of a certain length is formed by processing, a centering ridge extends continuously and hangs down from an eccentric position on the flat lower surface of the block, and a penetrating opening is made along the vertical center line of the centering ridge. The centering protrusion is inserted into and fitted into a vertical T-shaped keyway opening in the machining table of a machine tool so that it can be freely inserted and removed from above. By screwing and tightening the cap bolt inserted through the insertion hole with the vertical T-shaped nut inserted into the keyway of the processing table, the block body is positioned and fixed to the processing table in a state where it cannot be removed. The second feature is that

Furthermore, the method of using the holding jig consists of a block body with a fixed length whose cross-sectional shape is larger than a semicircle, and a centering convex line that continuously extends and hangs down from an eccentric position on the flat bottom surface of the block body. A total of 4 holding jigs equipped with 1 and 2 are processed and formed from one common metal round bar material, and are scattered on the processing table of the machine tool as a set of 4f[lil]. Each of the above-mentioned centering protrusions is inserted and fitted into the vertical T-shaped keyway opening in the processing table from above so that it can be freely inserted and removed from above, and the entire arcuate convex curved upper surface of the block body is used for machining. The present invention is characterized in that the workpiece is held in a self-centered state and the direction of the block body is reversed to cope with changes in the thickness of the workpiece.

<Operation> According to the above configuration of the present invention, the holding jig is provided with a centering protrusion extending from the lower surface of the semicylindrical block body and hanging down, and the centering protrusion opens into the processing table of the machine tool. It is designed to be inserted and fitted into the keyway from above, so when it is inserted and fitted, the centering protrusion serves as a key to the processing table, and the workpiece supported by the block body automatically It is possible to maintain accurate centering, and there is no need to readjust the centering of the workpiece using the jig every time the workpiece is attached or removed.

In addition, the above-mentioned centering protrusion is formed to protrude at an eccentric position on the block body, and can be inserted into and removed from the key groove of the processing table. The support interval for the workpiece can be adjusted wide or narrow using a pair of matching jigs on the left and right, and it can immediately respond to changes in the thickness of the workpiece. ! There's no need to.

<Example> Hereinafter, the present invention will be described in detail based on the drawings.
Figure 4 shows a basic embodiment of the workpiece holding jig (A), and (11) shows a fixed length (11) of a metal round bar (M).
L) is a block body manufactured and processed into an overall semicylindrical shape, and the cross-sectional shape of the cut end surface is particularly formed to be slightly larger than a semicircle. In other words, the block body (1
1) has a flat lower surface (11a) with a constant width (W) that is slightly smaller than the diameter dimension (D) of the round bar (M), and an upper surface (11b) that has an arcuate convex curve. However, as will be described later, the workpiece (12) is stably held as a pillow that makes linear contact with the circumferential surface of the workpiece (12). Note that (○) indicates the axis of the round bar (M).

In this regard, when turning, the diameter (D) of the round bar (M) and the constant length (L) of the block body (11) are both approximately 50 mm.
mm, and the constant width (W) of its lower surface (11a) is approximately 44 mm.
However, considering the relationship between these dimensions and the thickness and length of the workpiece (12), several feet of different sizes are prepared in advance. By the way, the above diameter dimension (D) and length (L)
In addition to about 50mm, about 751 and about 100mm
By preparing small, medium, and large size products 31 that are sized as follows, it is possible to widely handle most workpieces (12).

Further, (13) is a centering protrusion that extends continuously and integrally from the eccentric position of the flat lower surface (11a) of the block body (11), and its cross-sectional shape and size are similar to the machining table of the machine tool ( T)
It is formed with high precision so that it can fit accurately into the upper part of the opening of the letter-shaped keyway (14). In other words, by fitting the centering protrusion (13) as a key to the key a (14) of the processing table (T), the workpiece (12) can be held in the centered state by itself. That is why it has become so. However, the centering protrusion (13) is key a (14)
On the other hand, it is also possible to insert and remove the connector from above with one's hand without using a special tool. The vertical center line (H-
H) is the vertical diameter line (Y-
A constant amount eccentric from Y) is illustrated by the symbol (X).

(15) is the vertical center line (IJ) of the centering convex strip (13).
-H) A stepped bolt insertion hole opened through the upper part of the block body (11).
(16) can be inserted and removed freely. In that case, the large diameter head (16a) of the cap bolt (16)
) is latched to the intermediate step (15a) of the bolt insertion hole (15), and the head (16a) is defined so as not to protrude from the upper surface (11b) of the block body (11). (
IJ) is the threaded shaft part (16) of the cap bolt (16).
b), which is screwed into the nut and has an upright T-shape in cross-section corresponding to the keyway (14') of the processing table (T), and is free from the risk of slipping in the keyway (14). do not have.

Therefore, in advance, insert the (17) into the key a (14) of the machining table (T) with two freely sliding holes, and then insert the cap bolt (16) from above.
By screwing and tightening, the block main body (11) is irremovably positioned at an arbitrary position on the processing table (T) with its centering protrusion (13) fitted into the key a (14). Can be fixed.

Also, slightly loosen the cap bolt (16) and loosen the keyway (
14), it is also possible to change the fixed position of the block body (11) with respect to the processing table (T). Note that (16c) is a locking groove for a rotary operation tool cut out in the head (16a) of the cap bolt (16), and has a regular polygonal shape in plan view.

However, due to the eccentric position of the lower surface (11a) of the semicircular block main body (11), which has a slightly larger cross-sectional shape than a semicircle, a centering protrusion (13) that acts as a key for the keyway (14) of the processing table (T) is formed. ) is an overhanging and hanging jig (A), the installation of the bolt insertion hole (15) may be omitted as shown in the modified embodiment of Fig. 6.7. Lid and jig for its modified example (A)
Even if the workpiece (12) and -
When the block is positioned and fixed on the processing table (T), its centering protrusion (13) fits with the key ili (14) of the processing table (T) as shown in Fig. 13, and the block body The upper surface (11b) of the (IJ)
2) can be automatically maintained in a centered state.

In any case, the holding jig (A) consisting of the block body (11) and the centering protrusion (13) is machined by planing from a single round metal bar (M) as shown in Fig. 5. In addition, they are cut into a certain length (L) and used as a set of four pieces to support a workpiece (12). For example, one of the jigs (A) from each different metal round bar material (M)
When manufacturing and processing each piece one by one, due to variations in the dimensional accuracy of the round bar material (M) itself, so-called pair errors occur in the processing accuracy of the top jig (A), so one common The centering accuracy for holding the workpiece can be improved by manufacturing and processing the jigs (A) to be used as a set in large numbers at once from the metal round bar material (M) to be used as a set. It is.

In that case, as mentioned above, the cross-sectional shape of the block body (11) is formed to be slightly larger than a semicircle, so it is possible to reduce the loss of scraping from the metal round bar material (M), which is useful for so-called material removal. In addition, the block body (11)
Since the axial center (0) of the round bar material (M) remains, use the axial center (○) as a reference and measure it with a micrometer, etc. to perform the above-mentioned centering process. Inspecting and repairing accuracy becomes extremely easy.

The workpiece (1
2) is held on the machining table (T) of the machine tool, a total of four of the jigs (A) are used as one set, and the machining table (T) is held as shown in Figures 8 to 12. They will be scattered throughout the area.

In other words, there are many keys 1 on the processing table (T) of the machine tool.
t(14) is 111% between the adjacent left and right sides.
Since (Pi) is maintained and the opening rows are arranged in parallel,
Taking into account the size and length of the workpiece (12), each jig (A) is installed so that a total of four jigs (A) can form a stable support pillow for the workpiece (12). ) centering convex strip (
13) into an arbitrary keyway (14) from above and fit it, and then screw the cap bolt (16) from above into the nut (17) that was previously inserted into the keyway (14). By joining and tightening, the block body (
11) Position and fix.

By doing so, the circumferential surface of the workpieces (12) placed over a total of four pieces of the jig (A) will be aligned with the block body (IJ).
It is stably supported in a state of line contact with the arcuate convex curved upper surface (11b), and together with the key-fitting action of the centering convex strip (13) with respect to the key groove (14), the machining The object (12) is automatically maintained in an accurate centering state.

In that case, since the centering protrusion (13) of each jig (A) hangs down at a position offset by a certain amount (X) from the block body (11), the comprehensive comparison shown in Figs. As suggested by the above, by reversing the direction of the block body (11), it is possible to adjust the support interval (S) of the workpiece (12) by the left and right pairs of adjacent jigs (A). As a result, it is possible to immediately respond to changes in the size of the workpiece (12).

Further, if the thickness is constant, the height of the workpiece (12) protruding from the processing table (T) can be suppressed to a low level, and the supporting rigidity and stability during processing can be improved. Furthermore, as described above, since the block body (11) has a semicircular cross-sectional shape larger than a semicircle, the circumferential surface of the workpiece (12) is supported in a floating state from the processing table (T). This makes it easy to handle changes in the thickness of the workpiece (12).

Such effects can also be achieved with the holding jig (A) shown in the modified embodiment shown in Fig. 6.7. Using the cap bolt (16) and its nut (17), the workpiece (12) can be attached to the presser foot (7) as shown in Fig. 17 without positioning the block body (11) on the processing table (T).
) or other known ramp means to fix the presser foot to the processing table (T) from above, the holding jig (A) will also be positioned and fixed at the same time. be.

In the case of the present invention, the workpiece (
As the clamping means (12), a wide variety of conventionally known clamping means can be used, but in particular, if a ramp means as shown in Fig. It can be said to be more effective in that it can be processed without any problems.

In Figures 14 and 15, which show the effective ramp means, (18) is a pair of left and right clamp stands that face each other in an L-shape when viewed from the front, and the key groove (14) of the processing table (T). The installation is fixed to the processing table (T) by a nut (19) inserted therein and a cap (20) screwed onto the nut (20) from above.

The cap bolt (20) and nut (19) have the same structure as the cap bolt (16) and nut (17) described above.

(21) is the clamp base (a plurality of horizontal screw holes formed through the vertical wall part, and there is a push pin)
(22) are screwed together so that they can be moved forward and backward, and the push bolts (22) are connected by the plurality of screw holes (21).
The installation height can be adjusted. Workpiece (1
Depending on the thickness change of 2), select the screw hole (2I) and insert the presser foot (22) into it to press the presser foot (described later) from behind.

Further, (23) is a presser foot that restrains the circumferential surface of the workpiece (12) from the lateral direction, and is provided with a long hole (24) extending in the lateral direction. A stand pole (25) extending vertically from the clamp base (18) is passed through the elongated hole (24), and is fixed from above with a nut (26). (27
) is combined with its stud bolt (25) to attach the presser foot (2).
3), and its presser foot (23)
It is screwed together at the base end of the.

Therefore, press the presser foot (23) from behind and press the bolt (22).
), the nut (26) is tightened to bring the tip of the presser foot (23) into contact with the circumferential surface of the workpiece (12) from the lateral direction.
The workpiece (12) can be fixed.

In this fixed state, there is no obstacle above the workpiece (12) that is completely heated, so it is possible to perform groove machining over the entire length of the workpiece (12) without any problem.

Further, the presser foot (23) has an L hole (24) formed therein, and a plurality of screw holes (21), which are arranged in a ζ shape so that the mounting height of the push port (22) can be adjusted. Therefore, it is possible to effectively cope with changes in the thickness of the workpiece (12).

In any case, when holding the workpiece (12) on the processing table (T), the key on the processing table (T) must be used! The adjacent left and right mutual spacing (Pl) in (14) is
If the workpiece (12) is too wide in relation to the thickness of the workpiece (12), an auxiliary table (14a) with narrow keyways (14a) with a narrow left-right spacing (P2) as shown in FIG.
28), and install and fix them in a stacked state on the processing table (T), and insert each jig (28) into the key groove (14a) of the auxiliary table (28) in the same manner as above.
The centering protrusion (13) of A) is inserted and fitted, and the workpiece (12) is supported by the block body (11).

(29) is a key groove formed in the lower surface of the auxiliary table (28), and the key (3) fitted between this and the key a (14) of the processing table (T).
0), the auxiliary table (28) is positioned and fixed to the processing table (T). As the auxiliary table (28) and the clamping means for the workpiece (12), any known means can be used.

In the illustrated embodiment, it has been explained that a total of four holding jigs (A) are used as one set, but when holding a short and small workpiece (12), the above-mentioned block body ( 11)
By increasing the length (L) of the jig (A),
It is also possible to use a total of two pieces as one string to hold the workpiece (12).

<Effects of the Invention> As described above, the workpiece jig (A) according to the present invention has a fixed length (L) formed by processing a metal round bar material (M) with a cross-sectional shape larger than a semicircle. Kamaboko-shaped block body (1
1) and a centering protrusion (13) that continuously extends and hangs down from the eccentric position of the flat lower surface (11a), and the centering protrusion (13) is connected to the machining table (T) of the machine tool.
) is designed to be inserted into and fitted into the T-shaped keyway (14) which opens in the cross-section and can be freely inserted and removed from above. be.

That is, in the case of the present invention, the workpiece (12) is
A centering protrusion (13) extends continuously and hangs down from the lower surface (11a) of the block body (11) that supports the block body (11), and the centering protrusion (I3) is inserted into the keyway (13) of the processing table (T). 14) from above, the centering protrusion (13) acts as a key to hold the workpiece on the processing table (T), and the workpiece (12) is automatically inserted into the workpiece (12). As a result, the workpiece (
Every time you attach or remove 1), do the same work as 1) (2)! There is no need to readjust the centering state (1) one by one, and the desired machining work can be started quickly. It has excellent preparatory workability.

Further, the centering protrusion (13) extends from the eccentric position of the block body (11) and hangs down, so that it can be inserted and fitted into the key 1 (14) of the processing table (T) so as to be freely inserted and removed from above. Since the block body (11) is
), it is possible to deal with changes in the thickness of the workpiece (12), and various workpieces (12) can be used.
It is possible to obtain a support state that is stable and highly rigid in response to the change in thickness of the workpiece (1), and unlike conventional methods, a large number of V-blocks (2) corresponding to changes in the thickness of the workpiece (1) are There is no need to prepare it. In this sense, mass production effects can be expected to the maximum.

In particular, if the configuration of claim 2 is adopted, in addition to achieving the above effects, the block body (work 1) of the jig (A) can be attached to the processing table by the cap bolt (16) and nut (17). Since it is possible to position and fix the workpiece (12) to (T) so that it does not come off, it is easy to continue to place the workpiece (12) on the opposite side, and the workpiece (12) can be kept stable in the -layer. There are also some positive effects.

As stated in claim 3, the jigs (A) of the present invention are made into a set of four in total, and the jigs (A) of the present invention are combined into one set. When processing and forming a single round metal bar (M), the round bar (M
) It is possible to eliminate the so-called pair error of the jig (A) due to the dimensional variation of the jig (A) itself, and to finish the pair with high accuracy in a timely manner, the centering state of the workpiece (12) is ensured. It is extremely useful as a tool for

[Brief explanation of drawings]

1 to 3 are front views, plan views, and side views showing basic embodiments of the holding jig according to the present invention, and FIG. 4 is 4-4 in FIG. 2.
A line sectional view, FIG. 5 is an oblique view showing the machining state of the metal round bar material, FIG. 6 is a plan view showing a modified embodiment of the holding jig corresponding to FIG. 2, and FIG. A sectional view taken along the line 7-7 in the figure,
Fig. 8.9 is a slope view and a plan view showing the usage state of the holding jig according to the basic embodiment, Fig. 10 is a sectional view taken along the line 10-10 in Fig. 9, and Fig. 11.12 is the same as Fig. 10. FIG. 13 is a cross-sectional front view showing two types of usage states in which the orientation of the corresponding holding jig is reversed; FIG. 13 is a cross-sectional front view showing a usage state of the holding jig according to a modified embodiment;
Fig. 14 is a plan view showing the clamped state of the workpiece;
The figure is an enlarged sectional view taken along the line 15-15 in Figure 14,
The figure is a sectional front view showing how the auxiliary tables are stacked and used, and FIG. 17 is a perspective view showing a conventional holding jig corresponding to FIG. 8. (11)...Block body (11a)...Bottom surface (1], b)...Top surface (12)...Workpiece (13)...Centering protrusion ( 14) (14a)... Keyway (15)... Bolt insertion hole (16)... Cap bolt (17)... Nut (28)... Auxiliary table (A ) ・ ...Holding jig (M) ・ ...Metal round bar material (T) ...Processing table (X) ...Eccentricity Figure 2 Figure 1 ■ Figure 3 Figure 4 Except for Shizukuto

Claims (1)

[Claims] 1. A semi-cylindrical block body (11) of a certain length (L) whose cross-sectional shape is larger than a semicircle and formed from a metal round bar material (M), and its flat lower surface (11a). ) is provided with a centering protrusion (13) that continuously extends and hangs down from the eccentric position of the centering protrusion (13).
) A holding jig for a workpiece, characterized in that the jig is designed to be inserted into and fitted into a vertical T-shaped keyway (14) opening in a vertical section (14) from above. 2. A semi-cylindrical block body (11) of a certain length (L) whose cross-sectional shape is larger than a semicircle is formed from a metal round bar material (M), and the flat bottom surface (11a) is continuous from the eccentric position. A centering protrusion (13) that extends and hangs integrally, and a stepped bolt insertion hole (15) that is opened through the centering protrusion (13) along the vertical center line (H-H) of the centering protrusion (13). The above-mentioned centering convex strip (13) is placed on the machining table (T) of the machine tool.
) The cap bolt (16) inserted through the bolt insertion hole (15) is inserted into and fitted into the keyway (14) with an upright T-shaped cross-section opening in the machining table ( T) keyway (14)
A feature is that the block body (11) is positioned and fixed to the processing table (T) in a state where it does not come off by screwing and fastening it with a cross-sectional vertical T-shaped nut (17) inserted therein. Holding jig for workpieces. 3. A semicircular block body (11) with a constant length (L) whose cross-sectional shape is larger than a semicircle, and its flat lower surface (
A total of four holding jigs (A) equipped with a centering convex strip (13) that continuously extends and hangs from the eccentric position of 11a) are formed by processing from one common metal round bar material (M). The machining table of the machine tool (T
) The respective centering protrusions (13) are inserted and removed from above into the vertical T-shaped key groove (14) opening in the processing table (T) so as to be distributed upwardly. When fitted, the entire arcuate convex curved upper surface (11b) of the block body (11) allows the workpiece (12) to be
A workpiece holding jig characterized in that it automatically holds the block in a centered state and also copes with changes in the thickness of the workpiece (12) by reversing the direction of the block body (11). How to use the ingredients.