Claw of clamp device

Abstract

To provide a claw of a clamp device exhibiting an excellent rod material centering function and capable of setting wide the range of a material diameter of a rod material to be gripped, and capable of gripping even a rod material low in flexural rigidity such as a rod material of a thin wire diameter without bending the rod material.SOLUTION: This claw of the clamp device is installed in a rod material feeder that feeds a rod material to a processor and rotary-supports the rod material, and comprises first and second clamp members arranged to be close to or away from each other. The first clamp member is provided with first and second claws arranged to be away from each other. The second clamp member is provided with an inner claw disposed to be engageable between the first and second claws. The second clamp member is provided with first and second auxiliary claws.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a jaw of a clamping device used in a material feeder that feeds bar stock to a processing machine such as an automatic lathe, for gripping the bar stock fed to the bar stock feeder. [Background technology]

[0002] The bar feeder continuously feeds long, thin bars into a processing machine such as an automatic lathe, and supports the bars while the processing machine is in operation.

[0003] Generally, a bar feeder includes a feed rod for pushing the bar in the axial direction, a finger chuck for gripping the rear end of the bar is rotatably provided at the tip of the feed rod, and a clamping device for centering the bar when the rear end of the bar is gripped by the finger chuck.

[0004] Various structures have been known for the clamping device provided in such a bar feeder. For example, as described in Patent Document 1, a clamping device for a bar feeder that clamps a bar introduced into the bar feeder from above and below with a pair of claws includes a slide rail extending in the vertical direction, a crank lever rotatably attached to the slide rail, a pair of sliders linearly guided by the slide rail and disposed above and below the center of rotation of the crank lever, a pair of links rotatably connected to either side of the center of rotation of the crank lever and rotatably connected to each of the pair of sliders, and a drive source for rotating the crank lever, wherein the pair of claws are coupled to each of the pair of sliders. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 11-320204 Summary of the Invention [Problem to be solved by the invention]

[0006] Conventionally, as a pair of claw pieces used in this type of clamp device, for example, as shown in Figures 9 and 10, a clamp device claw consisting of a first clamp member 101 and a second clamp member 102 is known. The first clamp member 101 has a first outer claw portion 110 and a second outer claw portion 120 formed in a substantially V-shape, and the second clamp member 102 has an inner claw portion 140 formed in a substantially V-shape. The inner claw portion 140 is disposed so as to be located between the first outer claw portion 110 and the second outer claw portion 120 along the Y direction as viewed in Figure 10.

[0007] With the claws of such a conventional clamping device, the first outer claw portion 110 and the second outer claw portion 120, which are formed in an approximately V-shape, as well as the inner claw portion 140, can restrain the sides of the bar B at multiple points, making it possible to accurately position (hereinafter referred to as centering) the bar B in directions intersecting the central axis of the bar B (the X direction and Z direction as viewed in Figure 9).

[0008] 11 and 12, the claws of the conventional clamp device are arranged such that the first outer claw portion 110, the second outer claw portion 120, and the inner claw portion 140 mesh with each other along the Y direction as viewed in Fig. 12. This allows the first clamp member 101 and the second clamp member 102 to approach each other, making it possible to grip even a bar B with a small material diameter.

[0009] However, when the jaws of such a conventional clamping device are used to grip a bar B, the points of action applied to the bar B by the first outer jaw 110, the second outer jaw 120, and the inner jaw 140 are positioned at positions shifted in the Y direction. Therefore, when the jaws of a conventional clamping device are used to grip a bar B having low bending rigidity, for example, a bar B having a thin wire diameter, there is a risk of bending the bar B when gripping it, as shown in FIG.

[0010] The present invention has been made to solve the above-mentioned problems, and aims to provide the claws of a clamping device which have excellent centering function for bar material, which can grip a wide range of bar material diameters from thin to thick, and which can grip even bar material with low bending rigidity without bending the bar material. [Means for solving the problem]

[0011] The present invention has been made to achieve the above object and has the following features.

[0012] The claw of a clamping device of the present invention is a claw of a clamping device provided on a bar stock supplying machine which supplies bar stock to a processing machine and rotatably supports the bar stock, and is characterized in that it comprises a first clamping member and a second clamping member which are arranged so that they can move towards and away from each other, the first clamping member comprises a first claw portion and a second claw portion which are arranged at a distance from each other, the second clamping member comprises an inner claw portion which is arranged so as to be able to mesh with the first claw portion and the second claw portion, and the second clamping member comprises a first auxiliary claw portion and a second auxiliary claw portion.

[0013] In the claws of the clamping device of the present invention, it is preferable that the first auxiliary claw portion is formed at a position opposite the first claw portion in the direction in which the clamping devices can move toward and away from each other, and the second auxiliary claw portion is formed at a position opposite the second claw portion in the direction in which the clamping devices can move toward and away from each other.

[0014] In the claws of the clamping device of the present invention, it is preferable that the first claw portion has a first gripping surface formed in an approximately V-shape, the second claw portion has a second gripping surface formed in an approximately V-shape, and the inner claw portion has an inner gripping surface formed in an approximately V-shape.

[0015] In the claws of the clamping device of the present invention, it is preferable that the first auxiliary claw portion has a first auxiliary gripping surface continuous with the inner gripping surface, and the second auxiliary claw portion has a second auxiliary gripping surface continuous with the inner gripping surface.

[0016] In the claw of the clamping device according to the present invention, it is preferable that the first clamping member is formed with a relief hole for avoiding interference with the inner claw portion.

[0017] In the claw of the clamping device of the present invention, it is preferable that the second clamping member is formed with a first recess for avoiding interference with the first claw portion and a second recess for avoiding interference with the second claw portion.

[0018] The above summary of the invention does not list all of the features necessary for the present invention, and any subcombination of these features may also constitute an invention. Effect of the Invention

[0019] The claws of the clamping device of the present invention allow the bar to be centered with high precision and the range of bar diameters that can be gripped can be set wide, so that even bar materials with low bending rigidity can be gripped without bending the bar. [Brief description of the drawings]

[0020] [Figure 1] 1 is a schematic diagram of a bar feeder according to an embodiment of the present invention; [Diagram 2] FIG. 4 is a perspective view showing a claw of the clamp device according to the embodiment of the present invention. [Diagram 3] FIG. 4 is a view showing a claw of the clamp device according to the embodiment of the present invention as viewed from the Y direction. [Figure 4] FIG. 4 is a view showing a claw of the clamp device according to the embodiment of the present invention as viewed from the Z direction. [Diagram 5] 4 is a view of the claws of the clamping device according to the embodiment of the present invention, viewed from the Y direction, showing a state in which a bar material with a thick wire diameter is gripped. FIG. [Figure 6]4 is a view of the claws of the clamping device according to the embodiment of the present invention, viewed from the Z direction, showing the position of the point of action when gripping a bar material with a thick wire diameter. FIG. [Figure 7] FIG. 13 is a view from the Y direction showing the claws of the clamping device according to the embodiment of the present invention gripping a rod material with a thin wire diameter. [Figure 8] FIG. 4 is a view of the claws of the clamping device according to the embodiment of the present invention, viewed from the Z direction, showing the position of the point of action when gripping a rod material with a thin wire diameter. [Figure 9] FIG. 13 is a view showing the claws of a conventional clamp device as viewed from the Y direction. [Figure 10] FIG. 13 is a view showing the claws of a conventional clamping device as viewed from the Z direction. [Figure 11] 13 is a view from the Y direction showing the claws of a conventional clamping device gripping a rod material with a thin wire diameter. FIG. [Figure 12] FIG. 13 is an image showing a cross section cut in the Z direction of the jaws of a conventional clamping device, showing the jaws being bent when gripping a thin rod material. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Preferred embodiments for carrying out the present invention will be described below with reference to the drawings. Note that the following embodiments do not limit the inventions according to the claims, and all of the combinations of features described in the embodiments are not necessarily essential to the solution of the invention.

[0022] FIG. 1 is a schematic diagram of a bar material feeder according to an embodiment of the present invention, FIG. 2 is a perspective view showing a claw of a clamping device according to an embodiment of the present invention, FIG. 3 is a front view showing the claw of the clamping device according to an embodiment of the present invention from the Y direction, and FIG. 4 is a plan view showing the claw of the clamping device according to an embodiment of the present invention from the Z direction. Here, in FIG. 2, FIG. 3, and FIG. 4, the arrow X indicates the left-right direction of the claw C of the clamping device attached to the clamping device S (not shown), the left direction is indicated as the X1 direction, and the right direction is indicated as the X2 direction. In addition, in FIG. 2 and FIG. 4, the arrow Y indicates the central axis direction of the bar material B, the front direction is indicated as the Y1 direction, and the rear direction is indicated as the Y2 direction. In addition, in FIG. 2 and FIG. 3, the arrow Z indicates the up-down direction of the claw C of the clamping device attached to the clamping device S (not shown), the upper direction is indicated as the Z1 direction, and the lower direction is indicated as the Z2 direction. Note that these arrows are the same in FIG. 5 to FIG. 8 and FIG. 9 to FIG. 12 showing a conventional clamping device, which will be described later. In this specification, the central axis direction of the bar B is defined as the central axis direction of the bar B in a state where it is fed to the bar feeder M1.

[0023] The bar feeder M1 of this embodiment, as an example, supplies material to a bar processing machine called an automatic lathe (hereinafter referred to as "processing machine M2"), and is positioned adjacent to the processing machine M2 as shown in Figure 1.

[0024] The bar feeder M1 includes a main body 5 that feeds a bar B as a material to the processing machine M2.

[0025] The main body 5 includes a bar support device 7 that holds a bar B supplied from outside, and a bar feed section 6 that feeds the bar B to the processing machine M2. The bar B held by the bar support device 7 has its rear end gripped by the bar feed section 6 and is fed to the processing machine M2. The main body also includes a clamp device S that centers the bar B when the bar feed section 6 grips it.

[0026] On the other hand, the processing machine M2 has a cylindrical main shaft 4 through which the bar B can pass, and this main shaft 4 is provided with a chuck 4a that holds the tip of the bar B. The bar B delivered from the bar feeder M1 is rotated while being held by the chuck 4a, and is processed by a predetermined cutting tool (not shown).

[0027] The bar delivery section 6 is provided with a pusher 8 for transporting the bar B received by the bar support device 7 to the processing machine M2.

[0028] As an example, the pushing tool 8 includes a slider 8a with a circular cross section that can move freely back and forth along the longitudinal direction of the bar support device 7, a push rod 8b that is positioned in front of the slider 8a and pushes out the bar B, and a finger chuck 8c that is positioned in front of the push rod 8b via a bearing and grips the rear end of the bar B.

[0029] The clamp device S, for example, includes a slide rail fixed to the main body 5, and a pair of slide blocks that are guided by the slide rail and can move toward and away from each other. The pair of slide blocks, for example, are arranged to be movable symmetrically about the central axis of the bar B. In addition, a pair of clamp device claws C for gripping the bar B are attached to the pair of slide blocks.

[0030] The jaws C of the pair of clamping devices temporarily clamp the vicinity of the rear end of the bar B supplied to the bar support device 7. As a result, the bar B clamped by the jaws C of the clamping devices is centered with the finger chuck 8c.

[0031] As the structure of the clamp device S for performing the clamping action using the claws C of such a pair of clamp devices, various structures are known, such as a structure using multiple gears or a structure using multiple links, but since these structures have been publicly known for a long time, their description will be omitted.

[0032] After centering of the bar B with the finger chuck 8c is completed, the push rod 8b is advanced toward the bar B, and the rear end of the bar B is gripped by the finger chuck 8c. When the finger chuck 8c grips the bar B, the clamping device S releases the bar B from its clamping position.

[0033] The bar B, whose rear end is gripped by the finger chuck 8c, is pushed out by the push rod 8b due to the movement of the slider 8a, so that the front end of the bar B is gripped by the chuck 4a of the processing machine M2 and sent toward the processing machine M2 until it hits a stopper (not shown).

[0034] As shown in FIG. 1, a bar support unit 9 for rotatably supporting the bar B is provided in front of the bar support device 7, and this bar support unit 9 prevents the bar B from swinging around.

[0035] Next, the claw C of the clamp device according to this embodiment will be described.

[0036] 2, a claw C of the clamping device according to this embodiment includes a first clamping member 1 and a second clamping member 2. The first clamping member 1 and the second clamping member 2 are disposed on both sides in the X direction, sandwiching a bar B supplied to a bar supplying machine M1.

[0037] 3, the first clamp member 1 includes a first claw portion 10 and a second claw portion 20 formed in a substantially V-shape that opens in the X2 direction when viewed from the Y direction. Further, the first clamp member 1 has through holes formed below the first claw portion 10 and the second claw portion 20 to be used for attachment to a slide block (not shown).

[0038] As shown in FIG. 4, the first claw portion 10 and the second claw portion 20 are disposed spaced apart in the Y direction, and a recess 30 is formed between the first claw portion 10 and the second claw portion 20.

[0039] The recess 30 is set so as to engage with an inner claw portion 40 of the second clamp member 2 described later. For this reason, the dimension L1 of the recess 30 in the Y direction is formed to be larger than the dimension L2 of the inner claw portion 40 in the Y direction.

[0040] In addition, in order to avoid interference between the recess 30 and an inner lower piece portion 42 of the second clamping member 2 described later when the recess 30 and the inner claw portion 40 are engaged with each other, the first clamping member 1 may be formed with an escape hole 31 penetrating in the X direction, as shown in FIG. 2.

[0041] 3, the first claw portion 10 includes a first upper piece portion 11 that constitutes one piece of the substantially V-shape and is disposed on the upper side, and a first lower piece portion 12 that constitutes the other piece of the substantially V-shape and is disposed on the lower side. In addition, it is preferable that the first lower piece portion 12 is formed larger than the first upper piece portion 11 in the X2 direction.

[0042] In this embodiment, the surface formed by the first upper piece 11 and the first lower piece 12 and opening in the X2 direction in a substantially V-shape is referred to as a first gripping surface 15. The first gripping surface 15 comes into contact with the side surface of the bar B when gripping the bar B. The first gripping surface 15 is disposed so as to face a first auxiliary gripping surface 51 of the second clamp member 2, which will be described later.

[0043] In addition, it is preferable that the angle α1 formed by the first gripping surface 15 is formed symmetrically above and below with respect to a horizontal plane passing through the apex of the substantial V-shape. In addition, it is preferable that the angle α1 is 120 degrees, for example.

[0044] 4, a first inclined surface 14 may be formed on the side surface in the Y2 direction of the first upper piece 11 and the first lower piece 12 so that the tip tapers toward the first gripping surface 15. In this case, the width W1 in the Y direction of the first gripping surface 15 is formed to be a sufficient dimension to face the first auxiliary gripping surface 51.

[0045] 3, the second claw portion 20 includes a second upper piece portion 21 that constitutes one piece of the substantially V-shape and is disposed on the upper side, and a second lower piece portion 22 that constitutes the other piece of the substantially V-shape and is disposed on the lower side. In addition, it is preferable that the second lower piece portion 22 is formed larger in the X2 direction than the second upper piece portion 21.

[0046] In this embodiment, the surface formed by the second upper piece 21 and the second lower piece 22 and opening in the X2 direction in a substantially V-shape is referred to as a second gripping surface 25. The second gripping surface 25 comes into contact with the side surface of the bar B when gripping the bar B. In addition, the second gripping surface 25 is disposed so as to face a second auxiliary gripping surface 61 of the second clamp member 2, which will be described later.

[0047] Moreover, it is preferable that the angle of the substantially V-shape formed by the second gripping surface 25 be equal to the angle α1 of the substantially V-shape formed by the first gripping surface 15 .

[0048] 4, a second inclined surface 24 may be formed on the side surface in the Y1 direction of the second upper piece 21 and the second lower piece 22 so as to taper toward the second gripping surface 25. The width dimension of the second gripping surface 25 in the Y direction is preferably formed to be large enough to face the second auxiliary gripping surface 61, and is preferably formed to be equal to the width W1 of the first gripping surface 15 in the Y direction.

[0049] 3 and 4, the second clamp member 2 includes an inner claw portion 40 formed in a substantially V-shape that opens in the X1 direction when viewed from the Y direction, a first auxiliary claw portion 50 arranged on a side surface of the inner claw portion 40 in the Y2 direction, and a second auxiliary claw portion 60 arranged on a side surface of the inner claw portion 40 in the Y1 direction. In addition, a through hole used for attachment to a slide block (not shown) is formed below the inner claw portion 40 in the second clamp member 2.

[0050] The inner claw portion 40 includes an inner upper piece portion 41 that constitutes one piece of the substantially V-shape and is disposed on the upper side, and an inner lower piece portion 42 that constitutes the other piece of the substantially V-shape and is disposed on the lower side. It is preferable that the inner lower piece portion 42 be formed larger in the X1 direction than the inner upper piece portion 41.

[0051] In this embodiment, the surface formed by the inner upper piece 41 and the inner lower piece 42 and facing the X1 direction in a substantially V-shape is referred to as the inner gripping surface 43. The inner gripping surface 43 comes into contact with the side surface of the bar B when gripping the bar B. As shown in FIG. 4, the inner upper piece 41 and the inner lower piece 42 may be provided with a plurality of valleys 44 so that the contact area between the inner gripping surface 43 and the side surface of the bar B is reduced when gripping the bar B. This increases the surface pressure at the contact portion between the inner gripping surface 43 and the bar B, preventing slippage between the inner gripping surface 43 and the bar B and enabling the bar B to be gripped reliably.

[0052] In addition, it is preferable that the angle α2 formed by the inner gripping surface 43 is formed symmetrically above and below with respect to a horizontal plane passing through the apex of the substantially V-shape. In addition, it is preferable that the angle α2 is equal to the angle α1 formed by the first gripping surface 15, for example.

[0053] In this embodiment, the dimension L2 in the Y direction of the inner claw portion 40 is formed to be smaller than the dimension L1 in the Y direction of the recess 30, and is set so as to mesh with the recess 30 of the first clamp member 1. It is preferable that the dimensions L1 and L2 are set so that an appropriate gap is formed between both side surfaces in the Y direction of the inner claw portion 40 and both side surfaces in the Y direction of the recess 30 when the inner claw portion 40 and the recess 30 are in a state of meshing with each other.

[0054] As shown in FIG. 3, the first auxiliary claw portion 50 is formed in a substantial V-shape that opens in the X1 direction when viewed from the Y direction, and includes a first auxiliary gripping surface 51 that is continuous with the inner gripping surface 43.

[0055] As shown in FIG. 4, the first auxiliary gripping surface 51 is disposed to face the first gripping surface 15 of the first clamp member 1, and contacts the side of the bar B when gripping the bar B having low bending rigidity, e.g., a thin wire diameter. The width W2 of the first auxiliary gripping surface 51 in the Y direction is formed larger than the gap between the side of the inner claw portion 40 in the Y2 direction and the side of the recessed portion 30 in the Y1 direction when the inner claw portion 40 and the recessed portion 30 are engaged with each other, and is set to a dimension sufficient to face the first gripping surface 15. In this way, by facing the first auxiliary gripping surface 51 and the first gripping surface 15, when gripping the bar B having low bending rigidity, e.g., a thin wire diameter, the action point between the first auxiliary gripping surface 51 and the bar B and the action point between the first gripping surface 15 and the bar B can be aligned in the Y direction.

[0056] A recess 52 is formed in the vertical direction of the first auxiliary claw portion 50 so as to coincide with the Y2-direction side surface of the inner claw portion 40. By providing such a recess 52, the inner claw portion 40 can engage with the recess 30 without interfering with the first upper piece portion 11 and the first lower piece portion 12 of the first clamp member 1.

[0057] As shown in FIG. 3, the second auxiliary claw portion 60 is formed in a substantial V-shape that opens in the X1 direction when viewed from the Y direction, and includes a second auxiliary gripping surface 61 that is continuous with the inner gripping surface 43.

[0058] 4, the second auxiliary gripping surface 61 is disposed to face the second gripping surface 25 of the first clamp member 1, and contacts the side of the bar B when gripping a bar B having low bending rigidity, for example, a thin wire diameter. The width dimension in the Y direction of the second auxiliary gripping surface 61 is set to be equal to the width W2 in the Y direction of the first auxiliary gripping surface 51. In other words, the width dimension in the Y direction of the second auxiliary gripping surface 61 is formed to be larger than the gap between the side surface of the inner claw portion 40 in the Y1 direction and the side surface of the recessed portion 30 in the Y2 direction when the inner claw portion 40 and the recessed portion 30 are engaged with each other, and is set to a dimension sufficient to face the second gripping surface 25. In this way, by opposing the second auxiliary gripping surface 61 and the second gripping surface 25, when gripping a rod B having low bending rigidity, for example, a thin wire diameter, the point of action between the second auxiliary gripping surface 61 and the rod B and the point of action between the second gripping surface 25 and the rod B can be aligned in the Y direction.

[0059] A clearance 62 is formed in the vertical direction of the second auxiliary claw portion 60 so as to coincide with the Y1-direction side surface of the inner claw portion 40. By providing such a clearance 62, the inner claw portion 40 can engage with the recess 30 without interfering with the second upper piece portion 21 and the second lower piece portion 22 of the first clamp member 1.

[0060] Next, the effect of gripping the bar B with the jaws C of the clamping device according to this embodiment will be described.

[0061] Fig. 5 is a view of the jaws of the clamping device according to the embodiment of the present invention, seen from the Y direction, showing a state where the jaws grip a bar B with a thick wire diameter, Fig. 6 is a view of the jaws of the clamping device according to the embodiment of the present invention, seen from the Z direction, showing the position of the point of application when gripping a bar B with a thick wire diameter, Fig. 7 is a view of the jaws of the clamping device according to the embodiment of the present invention, seen from the Y direction, showing the state where the jaws grip a bar B with a thin wire diameter, and Fig. 8 is a view of the jaws of the clamping device according to the embodiment of the present invention, seen from the Z direction, showing the position of the point of application when gripping a bar B with a thin wire diameter. The white arrows shown in Figs. 6 and 8 indicate the force acting on the bar B.

[0062] The first and second gripping surfaces 15 and 25, and the inner gripping surface 43 are formed symmetrically with respect to a horizontal plane passing through the apex of the approximate V-shape. Therefore, as shown in Fig. 5 and Fig. 7, the central axis of the bar B gripped by the first and second gripping surfaces 15 and 25, and the inner gripping surface 43 is centered so as to coincide with the height of the apex of the approximate V-shape.

[0063] Furthermore, in the claws C of the clamping device according to this embodiment, the first lower piece 12 and the second lower piece 22 are formed to be longer in the X2 direction than the first upper piece 11 and the second upper piece 21, and the inner lower piece 42 is formed to be longer in the X1 direction than the inner upper piece 41. Therefore, when the bar B is gripped by the claws C of the clamping device, the first lower piece 12, the second lower piece 22 and the inner lower piece 42 can grip the bar B as if scooping it up from below, making it possible to easily center the bar B.

[0064] When a bar B with a thick wire diameter is gripped using the jaws C of the clamping device according to this embodiment, as shown in Fig. 5, the side surface of the bar B in the X1 direction is gripped by the first gripping surface 15 and the second gripping surface 25, and the side surface in the X2 direction is gripped by the inner gripping surface 43. At this time, the side surface of the bar B does not come into contact with the first auxiliary gripping surface 51 and the second auxiliary gripping surface 61. At this time, as shown in Fig. 6, the point of application of the force applied to the bar B from the X1 direction and the point of application of the force applied to the bar B from the X2 direction are shifted in the Y direction, but the bar B with a thick wire diameter is not bent by being gripped by the jaws C of the clamping device because of its high bending rigidity.

[0065] When the jaws C of the clamping device according to this embodiment are used to grip a rod B having low bending rigidity, e.g., a rod B having a thin wire diameter, the side surface of the rod B in the X1 direction is gripped by the first gripping surface 15 and the second gripping surface 25, and the side surface of the rod B in the X2 direction is gripped by the first auxiliary gripping surface 51 and the second auxiliary gripping surface 61, as shown in Fig. 7. At this time, as shown in Fig. 8, the point of application of the force applied to the rod B from the X1 direction and the point of application of the force applied to the rod B from the X2 direction are at the same position in the Y direction, so that no shear force or bending moment is applied to the rod B. Therefore, according to the jaws C of the clamping device according to this embodiment, even when the rod B having low bending rigidity, e.g., a rod B having a thin wire diameter is gripped, the rod B is not bent.

[0066] In addition, when the claw C of the clamping device according to this embodiment is used to grip a rod B having a low bending stiffness, for example, a thin wire diameter, as shown in FIG. 7, the inner claw portion 40 engages with the recess 30, but since the first clamping member 1 has an escape hole 31, the inner lower piece portion 42 does not interfere with the recess 30. Furthermore, since the second clamping member 2 has a first escape portion 52 and a second escape portion 62, the first claw portion 10 and the second claw portion 20 do not interfere with the first auxiliary claw portion 50 and the second auxiliary claw portion 60, respectively. The size of the first auxiliary gripping surface 51 and the second auxiliary gripping surface 61 and the range of the first escape portion 52 and the second escape portion 62 may be appropriately set so as to correspond to the wire diameter of the rod B having a low bending stiffness to be gripped.

[0067] In the above, the clamp device S has been described as gripping the bar B from the X direction using the first clamp member 1 and the second clamp member 2, but the direction in which the bar B is gripped is not limited to this, and the clamp device S may be configured to grip the bar B from the Z direction or another direction intersecting the central axis of the bar B. It is clear from the claims that such modified or improved forms are also included within the technical scope of the present invention.

[0068] 1 first clamp member, 2 second clamp member, 10 first claw portion, 11 first upper piece portion, 12 first lower piece portion, 14 first inclined surface, 15 first gripping surface, 20 second claw portion, 21 second upper piece portion, 22 second lower piece portion, 24 second inclined surface, 25 second gripping surface, 30 recess, 31 relief hole, 40 inner claw portion, 41 inner upper piece portion, 42 inner lower piece portion, 43 inner gripping surface, 44 valley portion, 50 first auxiliary claw, 51 first auxiliary gripping surface, 52 first relief portion, 60 second auxiliary claw, 61 second auxiliary gripping surface, 62 second relief portion, C claw of clamp device, S clamp device.

Claims

1. A claw of a clamping device provided in a bar material feeder that feeds a bar material to a processing machine and rotatably supports the bar material, a first clamp member and a second clamp member arranged so as to be movable toward and away from each other; The first clamp member includes a first claw portion and a second claw portion that are spaced apart from each other, the second clamp member includes an inner claw portion intermeshably disposed between the first claw portion and the second claw portion, The second clamp member has a first auxiliary claw portion and a second auxiliary claw portion.

2. 2. The clamping device of claim 1, the first auxiliary claw portion is formed at a position facing the first claw portion in the direction in which the first auxiliary claw portion can approach and separate from the first claw portion, The claw of a clamping device, wherein the second auxiliary claw portion is formed at a position opposite to the second claw portion in the direction in which the clamping device can move toward and away from the second claw portion.

3. 2. The clamping device of claim 1, The first claw portion includes a first gripping surface formed in a generally V-shape, The second claw portion includes a second gripping surface formed in a generally V-shape, The clamping claw, wherein the inner claw portion has an inner gripping surface formed generally in a V-shape.

4. The clamping device of claim 3, further comprising: The first auxiliary claw portion includes a first auxiliary gripping surface that is continuous with the inner gripping surface, The claw of a clamping device, wherein the second auxiliary claw portion has a second auxiliary gripping surface continuous with the inner gripping surface.

5. 2. The clamping device of claim 1, The claw of a clamping device, wherein the first clamping member is formed with an escape hole for avoiding interference with the inner claw portion.

6. 2. The clamping device of claim 1, The claw of a clamping device, wherein the second clamping member is formed with a first recess for avoiding interference with the first claw portion and a second recess for avoiding interference with the second claw portion.

Images