Crimping tools

Abstract

To provide a swaging tool that is configured so that a press die or a yoke die is prevented from being wrongly mounted thereon.SOLUTION: A head part 10 is provided at a tip part of a tool main body 2 of a swaging tool 1. A holding part 11 of the head part 10 is made to hold a part 22 to be held of a press die 20 attachably and detachably. A pair of parts 33 to be connected of a yoke die 30 are attachably and detachably connected to a pair of connection parts 13 of the head part 10. The holding part 11 and at least either of the pair of connection parts 13 are made asymmetrical with respect to an axis line L. The part 22 to be held and a portion corresponding to the either made asymmetrical of the pair of parts 33 to be connected are made asymmetrical with respect to the axis line L.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a crimping tool for crimping objects such as pipe joints for air conditioning piping and water / hot water supply piping, and more particularly to an assembly-type crimping tool in which the press die and yoke die are detachable from the head portion. [Background technology]

[0002] This type of crimping tool has a semi-annular press die and a yoke die provided in a head portion at the tip of the tool body (see Patent Documents 1 to 4, etc.). The press die is accommodated in a holding recess in the head portion so as to be able to advance and retreat, and is detachably connected to a piston (output shaft) of an advance and retreat drive unit in the tool body. The yoke die is connected to the head portion so as to face the press die on the tip side of the press die. The semi-annular press die and yoke die have a plurality of compression protrusions provided on their inner peripheral surfaces so as to extend in the circumferential direction.

[0003] The pipe fitting fitted to the end of an air conditioning pipe or cold / hot water pipe is sandwiched between the press die and the yoke die, and the press die is advanced by the forward / backward drive unit, thereby crimping and fixing the pipe fitting to the end of the pipe. A crimping tool is also known in which the compression projections of the press die and yoke die are arranged at uneven intervals in order to improve the sealing properties (airtightness and liquid tightness) between the crimped pipe fitting and the pipe end. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-132516 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-066897 [Patent Document 3] Japanese Patent Application Laid-Open No. 2013-249848 [Patent Document 4] Japanese Patent Application Laid-Open No. 2011-224738 Summary of the Invention [Problem to be solved by the invention]

[0005] When the object to be crimped is a large object, such as a large-diameter pipe fitting, an assembly-type crimping tool in which the press die and yoke die are detachable from the head is suitable for the purpose of ease of clamping the object between the press die and yoke die and the need to be able to withstand a large load during crimping. However, with such an assembly-type crimping tool, it is possible that the press die or yoke die may be mistakenly attached with the left and right sides reversed during assembly. If this happens, for example, in a crimping tool in which the compression protrusions are not uniformly spaced, the position of the compression protrusions may be changed, resulting in poor crimping and the risk of gas or water leaks. In view of the above circumstances, an object of the present invention is to prevent the press die and yoke die from being erroneously attached to an assembly type crimping tool. [Means for solving the problem]

[0006] In order to achieve the above object, a crimping tool according to the present invention is a crimping tool for crimping an object, a tool body in which the forward / backward drive unit is housed; a head portion provided at a tip end of the tool body in the axial direction, the head portion having a holding portion extending across an axis of the tool body and extending to both sides in a width direction perpendicular to the axis, and a pair of connecting portions sandwiching the holding portion on both sides in the width direction; a press die having a held portion that is detachably attached to the holding portion and is held so as to be movable forward and backward in the axial direction; a yoke die having a pair of connected portions that are detachably connected to the pair of connecting portions, respectively, and facing the press die on the tip side of the press die in the axial direction with the object sandwiched therebetween; an output shaft of the forward / backward driving unit is provided on the axis line, and the output shaft penetrates the head unit and is detachably connected to the press die, At least one of the holding portion and the pair of connecting portions is asymmetric with respect to the axis, The held portion and the portion of the pair of connected portions corresponding to the asymmetric portion are asymmetric with respect to the axis.

[0007] With this crimping tool, by making the holding portion and the held portion asymmetrical, if an attempt is made to attach the press die to the head portion with the orientation reversed, the held portion of the press die will not mate with the holding portion of the head portion, and they will not be able to be fitted together. Furthermore, by making the connecting portion and the connected portion asymmetrical, if an attempt is made to connect the yoke die to the head portion with the orientation reversed, the connected portion of the yoke die will not mate with the connecting portion of the head portion, and they will not be able to be connected together. This prevents incorrect installation of the press die or yoke die, and reliably prevents the crimping operation of the object with the die incorrectly installed.

[0008] Preferably, the holding portion includes a holding recess formed in the head portion so as to be open toward the tip end side and configured to accommodate the press die so as to be movable forward and backward, the held portion includes an outer surface facing an inner surface of the holding recess of the press die, Inner surface portions on both sides of the inner surface in the width direction across the axis are asymmetric with respect to the axis, The outer surface portions on both sides of the axis in the width direction of the outer surface are asymmetric with respect to the axis. With this crimping tool, if the press die is attached to the head portion in the reversed orientation, the outer surface of the press die will not match the inner surface of the holding recess in the head portion, which reliably prevents incorrect attachment of the press die.

[0009] Preferably, a locking groove extending in the axial direction is formed in one of the inner surface portion and the outer surface portion on the same side in the width direction, a locking protrusion that is fitted into the locking groove so as to be slidable in the axial direction is formed on the other of the inner surface portion and the outer surface portion on the same side; The locking grooves on both sides in the width direction and the locking protrusions on both sides in the width direction are asymmetrical in cross section perpendicular to the axis. With this crimping tool, if the press die is attached to the head portion in the reversed orientation, the locking protrusions and locking grooves will not align, thereby reliably preventing incorrect attachment of the press die.

[0010] Preferably, the inner surface portions on both sides each have an inclined inner surface portion that inclines toward the tip side as it moves away from the axis in the width direction, The outer surface portions on both sides each have an inclined outer surface portion that inclines toward the tip side as it moves away from the axis in the width direction, The inclination angles of the inclined inner surface portions on both sides and the inclined outer surface portions on both sides are different from each other. With this crimping tool, if the press die is attached to the head portion in the reverse direction, the inclined inner surface and the inclined outer surface will not match, which reliably prevents incorrect attachment of the press die.

[0011] Preferably, the widths of the inner surface portions on both sides are different from each other, and the widths of the outer surface portions on both sides are different from each other. More preferably, the width of the wider outer surface portion is greater than the width of the narrower inner surface portion. With this crimping tool, if the press die is attached to the head in the reverse direction, the connection portion of the press die with the output shaft will be misaligned in the width direction from the output shaft, making it impossible to connect. This reliably prevents incorrect attachment of the press die.

[0012] Preferably, one of the pair of connecting portions and the pair of connected portions on both sides in the width direction has a connecting recess, and the other has a connecting arm that is fitted into the connecting recess, The connecting recesses on both sides in the width direction and the connecting arms on both sides in the axial direction and the thickness direction perpendicular to the width direction are different in size from each other. More preferably, the thickness of the larger connecting arm is greater than the width dimension of the smaller connecting recess. With this crimping tool, if the yoke die is attached to the head portion in the reversed orientation, the larger connecting arm cannot be fitted into the smaller connecting recess, thereby reliably preventing incorrect attachment of the yoke die.

[0013] Preferably, the connecting portion and the connected portion on the same side in the width direction are connected to each other by a connecting pin passed through a pin hole formed in the connecting portion and the connected portion, The pin holes on both sides in the width direction have different hole diameters, and the connecting pins on both sides in the width direction have different diameters. More preferably, the diameter of the larger connecting pin is larger than the diameter of the smaller pin hole. With this crimping tool, if the yoke die is attached to the head portion in the reversed orientation, the larger connecting pin cannot be fitted into the smaller pin hole, thereby reliably preventing incorrect attachment of the yoke die. Preferably, the larger connecting pin and pin hole are arranged in the connecting portion and connected portion on the larger side of the connecting recess and connecting arm, and the smaller connecting pin and pin hole are arranged in the connecting portion and connected portion on the smaller side of the connecting recess and connecting arm. [Effects of the Invention]

[0014] According to the present invention, it is possible to prevent the press die or yoke die from being erroneously attached to the crimping tool. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a side view of a crimping tool according to one embodiment of the present invention. [Figure 2] FIG. 2 is a side view of the crimping portion of the crimping tool. [Figure 3] FIG. 3 is an exploded perspective view of the crimping portion. [Figure 4] FIG. 4 is a plan cross-sectional view taken along line IV-IV in FIG. [Figure 5]FIG. 5 is a plan sectional view showing an example of a situation in which the press die of the crimping action portion is about to be erroneously attached to the head portion. [Figure 6] FIG. 6 is a front view showing an example of a situation in which the press die is about to be erroneously attached to the head portion. [Figure 7] FIG. 7 is a front view showing an example of a situation in which the yoke die of the crimping action portion is about to be erroneously attached to the head portion. [Figure 8] FIG. 8 is a plan sectional view showing an example of a situation in which the yoke die is about to be erroneously attached to the head portion. [Figure 9] FIG. 9 is a plan sectional view showing an example of a situation in which the yoke die is about to be erroneously attached to the head portion. [Figure 10] FIG. 10 is a cross-sectional view taken along line XX in FIG. 2, showing how the crimping tool is used to crimp an object made of a pipe joint fitted with a pipe end portion. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 shows a crimping tool 1 according to this embodiment. As shown in Fig. 10, the object of crimping using the crimping tool 1 is, for example, a pipe fitting onto which a pipe end 8 of an air-conditioning pipe or a cold / hot water supply pipe is fitted. By crimping the pipe fitting 9 so as to compress it in the radial direction at multiple points, the pipe fitting 9 and the pipe end 8 are connected in an airtight or liquid-tight manner. The crimping tool 1 is particularly suitable for crimping a pipe fitting 9 with a large diameter.

[0017] <Crimping tool 1> As shown in FIG. 1, the crimping tool 1 includes a tool body 2 and a crimping portion 3 . <Tool body 2> The tool body 2 includes a casing 2c extending along the axis L and a grip 2g protruding laterally from the casing 2c. The casing 2c houses an advance / retract drive unit 4. A cylinder 4c of the advance / retract drive unit 4 is provided at the axial tip (upper side in Fig. 1) of the casing 2c. As shown in Fig. 2, a piston 4p (output shaft of the advance / retract drive unit) is housed in the cylinder 4c. The cylinder 4c and the piston 4p are arranged on the axis L. The piston 4p protrudes from the cylinder 4c to the tip side (upper side in Fig. 2). The advance / retract drive unit 4 drives the piston 4p to advance / retract along the axis L,

[0018] <Crimping part 3> As shown in Figures 1 and 2, a crimping portion 3 is provided at the axial tip of the casing 2c. The axis of the crimping portion 3 coincides with the axis L of the tool body 2. The width direction of the crimping portion 3, which is perpendicular to the axis L, is oriented left and right in Figure 2. As shown in Figure 10, the thickness direction (left and right direction in Figure 10) which is perpendicular to the axis L of the crimping portion 3, is oriented along the pipe axis L9 of the pipe fitting 9, which is the object to be crimped.

[0019] As shown in Fig. 3, the crimping action part 3 includes a head part 10, a press die 20, and a yoke die 30. These components 10, 20, and 30 of the crimping action part 3 can be freely disassembled and assembled. In particular, the press die 20 and the yoke die 30 can be freely separated from and assembled to the head part 10.

[0020] In the following description, unless otherwise specified, it is assumed that the crimping action part 3 is in a correctly assembled state (Fig. 2). In addition, when distinguishing between a pair of components on both sides of the axis L in the crimping action part 3 in the width direction, the component on one end side in the width direction (left side in Fig. 2) will be marked with "a" and the component on the other end side in the width direction (left side in Fig. 2) will be marked with "b".

[0021] <Head part 10> 2 and 3, the head portion 10 includes a holding recess 11 and a pair of connecting portions 13, and is formed in a generally V-shape or semi-annular shape. A shaft hole 10c is formed in the center of the head portion 10. A cylinder 4c is fitted into the shaft hole 10c.

[0022] The inner space of the head portion 10, which is generally V-shaped or semi-annular, forms a holding recess 11 (holding portion) that holds the press die 20. The holding recess 11 is open toward the tip side (upper side in FIG. 2). The inner surface of the holding recess 11 straddles the axis L and extends to both sides in the width direction (left and right in FIG. 2) perpendicular to the axis L. That is, the inner surface of the holding recess 11 includes inner surface portions 12 on both sides in the width direction across the axis L. Each inner surface portion 12 includes an inclined inner surface portion 16 and a lateral inner surface portion 18. Each inclined inner surface portion 16 is inclined toward the tip side (left and right in FIG. 2) as it moves away from the axis L in the width direction. The lateral inner surface portion 18 is continuous with the tip side of the inclined inner surface portion 16. The lateral inner surface portion 18 is parallel to the axis L and reaches the tip surface of the head portion 10.

[0023] 2 and 4, a locking groove 14 is formed in each side inner surface portion 18. The locking groove 14 extends in the axial direction (vertical in FIG. 2) and reaches the tip surface of the head portion 10. The groove width direction of the locking groove 14 is oriented in the thickness direction of the crimping portion 3 (vertical in FIG. 4).

[0024] The inner surface of the holding recess 11 includes a portion that is asymmetric with respect to the axis L. That is, inner surface portions 12a and 12b on both sides of the holding recess 11 are asymmetric with respect to the axis L. Specifically, as shown in Fig. 2, the inclination angles of the inclined inner surface portions 16a and 16b are different from each other, and the inclination angle θa relative to the width direction of the inclined inner surface portion 16a on the left side (one end side) in Fig. 2 is smaller than the inclination angle θb of the inclined inner surface portion 16b on the right side (the other end side) (θa<θb). Note that the difference between the inclination angles θa and θb in the figure is exaggerated, and the actual angle difference (θb-θa) is no more than a few degrees, making the difference almost imperceptible at first glance.

[0025] Further, the widths of the inner surface portions 12a and 12b are different from each other. In FIG. 2, the width La of the inner surface portion 12a on the left side (one end side) (the distance from the axis L to the side inner surface portion 18a) is smaller than the width Lb of the inner surface portion 12b on the right side (the other end side) (the distance from the axis L to the side inner surface portion 18b) (La < Lb). Note that the difference in the widths La and Lb in the figure is exaggerated, and the actual width difference (Lb - La) is less than a few percent of each of the widths La and Lb, and at a glance, the difference is hardly noticeable.

[0026] Furthermore, as shown in FIG. 4, the cross-sections orthogonal to the axis L of the locking grooves 14a and 14b on both sides are asymmetric with respect to each other. In FIG. 4, the groove width Wa of the locking groove 14a on the left side (one end side) is smaller than the groove width Wb of the locking groove 14b on the right side (the other end side) (Wa < Wb).

[0027] As shown in FIGS. 2 and 3, both sides in the width direction (left and right in FIG. 2) sandwiching the holding recess 11 in the head portion 10 constitute a pair of connecting portions 13 for connecting the yoke dies 30. A connecting recess 15 is formed in each connecting portion 13. The connecting recess 15 is opened at the tip surface (the upper surface in FIG. 2) of each side portion in the width direction of the head portion 10, and extends in the width direction to reach the outer surface and the inner surface of the head portion 10.

[0028] A pin hole 17 is formed in the connecting portion 13. The pin hole 17 penetrates the connecting portion 13 in the thickness direction of the caulking portion 3 (the direction orthogonal to the paper surface in FIG. 2).

[0029] The pair of connecting portions 13a and 13b are asymmetric. Specifically, as shown in FIG. 4, the sizes ta and tb in the thickness direction (up and down in FIG. 4) of the pair of connecting recesses 15a and 15b are different from each other. In FIG. 4, the size ta of the connecting recess 15a on the left side (one end side) is smaller than the size tb of the connecting recess 15a on the right side (the other end side) (ta < tb). Also, in FIG. 4, the hole diameter φa of the pin hole 17a on the left side (one end side) is smaller than the hole diameter φb of the pin hole 17b on the right side (the other end side) (φa < φb). Note that the hole diameter difference (φb - φa) in the figure is exaggerated.

[0030] <Press Die 20> As shown in FIG. 2, a press die 20 is housed in a holding recess 11. The press die 20 is formed in a roughly semi-annular shape. As shown in FIGS. 4 and 10, three (plural) compression protrusions 21 are formed on the inner surface of the press die 20. Each compression protrusion 21 extends in the circumferential direction of the inner surface of the press die 20. The intervals d1, d2 between adjacent compression protrusions 21 are non-uniform (d1≠d2). As shown in FIG. 3, on the front end surfaces 28 on both sides of the press die 20, protruding convex portions 28d are formed between the ends of the compression protrusions 21 spaced a short distance apart d1 (FIG. 10), and recesses 28e are formed between the ends of the compression protrusions 21 spaced a long distance apart d2 (FIG. 10).

[0031] As shown in Figures 2 and 10, a connection hole 25 (connection portion) is formed in the center of the press die 20. The piston 4p of the advance / retract drive unit 4 passes through the head portion 10 and is fitted into the connection hole 25. This allows the press die 20 and the piston 4p to be detachably connected. In turn, the press die 20 is detachably connected to the head portion 10 via the piston 4p and the cylinder 4c. The press die 20 is advanced and retracted in the axial direction (up and down in Figure 2) by the advance / retract drive of the piston 4p.

[0032] As shown in FIG. 2, the outer surface of the press die 20 constitutes a held portion 22. The held portion 22 faces the inner surface of the holding recess 11 and is held by the head portion 10. The held portion 22 spans both sides in the width direction (left and right in FIG. 2) across the axis L. That is, the held portion 22 (the outer surface of the press die 20) includes outer surface portions 23 on both sides in the width direction across the axis L. Each outer surface portion 23 includes an inclined outer surface portion 26 and a lateral outer surface portion 27. Each inclined outer surface portion 26 is inclined toward the tip side (left and right in FIG. 2) as it moves away from the axis L in the width direction.

[0033] A side outer surface portion 27 is connected to the tip side of the inclined outer surface portion 26. The side outer surface portion 27 is parallel to the axis L and reaches the tip surface of the head portion 10. 2 and 4, a locking protrusion 24 is formed on each side outer surface portion 27. The locking protrusion 24 extends in the axial direction (up and down in FIG. 2) with its width directed toward the thickness direction of the crimping portion 3 (up and down in FIG. 4). The locking protrusion 24a on the side outer surface portion 27a on the left side (one end) in FIG. 4 is fitted into the locking groove 14a so as to be slidable in the axial direction. The locking protrusion 24b on the side outer surface portion 27b on the right side (the other end) in FIG. 4 is fitted into the locking groove 14b so as to be slidable in the axial direction.

[0034] The portion of the held portion 22 corresponding to the asymmetric portion of the head portion 10 is asymmetric with respect to the axis L. That is, the outer surface portions 23a, 23b on both sides are asymmetric with respect to the axis L. Specifically, as shown in Fig. 2, the inclination angles of the inclined outer surface portions 26a and 26b are different from each other. In Fig. 2, the inclination angle of the inclined outer surface portion 26a on the left side (one end) is equal to the inclination angle θa of the inclined inner surface portion 16a. The inclination angle of the inclined outer surface portion 26b on the right side (the other end) is equal to the inclination angle θb of the inclined inner surface portion 16b.

[0035] Furthermore, the widths of the outer surface portions 23a and 23b are different from each other. In Fig. 2, the width of the outer surface portion 23a on the left side (one end side) is equal to the width La of the inner surface portion 12a. In Fig. 2, the width of the outer surface portion 23b on the right side (the other end side) is equal to the width Lb of the inner surface portion 12b. The width of the outer surface portion 23b on the wider side is greater than the width of the inner surface portion 12a on the narrower side.

[0036] Furthermore, as shown in Fig. 4, the cross sections of the locking protrusions 24a, 24b on both sides, perpendicular to the axis L, are asymmetrical with respect to each other. In Fig. 4, the width (dimension along the thickness direction of the crimping portion 3) of the locking protrusion 24a on the left side (one end) is equal to the groove width Wa of the locking groove 14a. The width of the locking protrusion 24b on the right side (the other end) is equal to the groove width Wb of the locking groove 14b. The width of the locking protrusion 24b on the wider side is greater than the width of the locking groove 14a on the narrower side.

[0037] <York Die 30> 2 and 3, the yoke die 30 is formed in a roughly semi-annular shape with an outer diameter larger than that of the press die 20 and an inner diameter equal to that of the press die 20. The yoke die 30 is disposed so as to face the press die 20 on the tip side (upper side in FIG. 2) of the press die 20. A crimping object 9, shown by a two-dot chain line in FIG. 2, is sandwiched between the yoke die 30 and the press die 20.

[0038] As shown in Figures 3 and 10, three (plural) compression protrusions 31 are formed on the inner surface of the yoke die 30. Each compression protrusion 31 extends circumferentially on the inner surface of the yoke die 30. The intervals d3, d4 between adjacent compression protrusions 31 are non-uniform (d3 ≠ d4). As shown in Figure 10, the narrow interval d3 portion of the yoke die 30 faces the wide interval d2 portion of the press die 20. The wide interval d4 portion of the yoke die 30 faces the narrow interval d1 portion of the press die 20.

[0039] As shown in Fig. 3, convex portions 38d are formed to protrude between the ends of the compression protrusions 31 of the yoke die 30 at narrow intervals d3 (Fig. 10), and concave portions 38e are formed between the ends of the compression protrusions 31 at wide intervals d4 (Fig. 10). The convex portions 38d of the yoke die 30 and the concave portions 28e of the press die 20 are fitted together, facing each other. The concave portions 38e of the yoke die 30 and the convex portions 28d of the press die 20 are fitted together, facing each other.

[0040] 2 and 3, a pair of connecting arms 33 (connected portions) are provided on both sides in the width direction of the yoke die 30. Each connecting arm 33 is fitted into the corresponding connecting recess 15.

[0041] Pin holes 37 are formed in the connecting arm 33. The pin holes 37 penetrate the connecting arm 33 in the thickness direction (the direction perpendicular to the paper surface in FIG. 2). Each pin hole 37 is aligned and communicates with a pin hole 17 of the corresponding connecting portion 13. A connecting pin 41 (described later) is inserted into the communicating pin holes 17, 37, whereby each connecting arm 33 is connected to the corresponding connecting portion 13.

[0042] The pair of connecting arms 33a, 33b are asymmetric with each other. In other words, the portion of the yoke die 30 corresponding to the asymmetric portion of the head portion 10 is asymmetric with respect to the head portion 10. Specifically, as shown in Fig. 4, the pair of connecting arms 33a, 33b have different thicknesses. In Fig. 4, the thickness of the connecting arm 33a on the left side (one end) is equal to the thickness dimension ta of the corresponding connecting recess 15a. The thickness of the connecting arm 33b on the right side (the other end) is equal to the thickness dimension tb of the corresponding connecting recess 15a. The thickness of the thicker connecting arm 33b is greater than the thickness ta of the connecting recess 15a on the small opening side.

[0043] Furthermore, the diameters of the pin holes 37a, 37b of the pair of connecting arms 33a, 33b are different from each other. In Fig. 4, the diameter of the pin hole 37a on the left side (one end) is equal to the diameter φa of the corresponding pin hole 17a. In Fig. 4, the diameter of the pin hole 37b on the right side (the other end) is equal to the diameter φb of the corresponding pin hole 17b. The small-diameter pin hole 37a is formed in the connecting arm 33a on the thinner side, and the large-diameter pin hole 37b is formed in the connecting arm 33b on the thicker side.

[0044] <Connecting member 40> 1 and 2, a connecting member 40 is provided on each of both widthwise sides of the crimping portion 3. The connecting member 40 detachably connects the connecting portion 13 of the head portion 10 and the connecting arm 33 (connected portion) of the yoke die 30.

[0045] 3 and 4, each connecting member 40 includes a connecting pin 41, a cap 42, and a spring 43. The connecting pin 41 is inserted through the pin holes 17, 37.

[0046] The pair of connecting pins 41 on both sides in the width direction of the crimping portion 3 have different diameters. Therefore, the pair of connecting members 30 are asymmetric with respect to each other. In FIG. 4, the diameter of the connecting pin 41a on the left side (one end) is equal to the hole diameter φa of the corresponding pin holes 17a, 37a. In FIG. 4, the hole diameter of the connecting pin 41b on the right side (the other end) is equal to the hole diameter φb of the corresponding pin holes 17b, 37b. The small-diameter connecting pin 41a is arranged on the thinner side of the connecting arm 33a, and the large-diameter connecting pin 41b is arranged on the thicker side of the connecting arm 33b. The diameter of the large-diameter connecting pin 41b is larger than the hole diameters of the small-diameter pin holes 17a, 37a.

[0047] The proximal end (lower end in FIG. 4) of each connecting pin 41 protrudes from the head portion 10, and a cap 42 is attached thereto. A compression coil spring 43 is fitted around the outer periphery of the connecting pin 41. The spring 43 is housed in the annular gap between the peripheral side of the cap 42 and the connecting pin 41, and in a compressed state, one end abuts against the top plate of the cap 42 and the other end abuts against the head portion 10. As a result, the spring force of the spring 43 acts to protrude the connecting member 40 from the head portion 10 toward the front (downward in FIG. 4).

[0048] As shown in Figure 4, a guide groove 44 is formed on the outer peripheral surface of the connecting pin 41. The guide groove 44 extends in the axial direction of the connecting pin 41. A tip 44e of the guide groove 44 does not reach the tip 41e of the connecting pin 41, but is positioned slightly before it. A lock groove 45 is continuous with the proximal end of the guide groove 44. The lock groove 45 extends a short distance in the circumferential direction of the connecting pin 41, perpendicular to the guide groove 44.

[0049] 4, a lock pin 50 is provided retractably on the inner circumferential surfaces of pin holes 17a and 17b inside the head portion 10. A lock spring 51 is housed inside the head portion 10. The lock spring 51 biases the lock pin 50 so that it protrudes from the inner circumferential surfaces of the pin holes 17a and 17b.

[0050] The lock pin 50 is fitted into the guide groove 44 and the lock groove 45 so as to be relatively movable. In the assembled crimping portion 3, the lock pin 50 is fitted into the lock groove 45. The connecting member 40 is locked so as not to be inserted or removed from the pin holes 17, 37. This prevents the head portion 10 and the yoke die 30 from being separated.

[0051] To unlock the connecting member 40, the connecting pin 41 is turned so that the lock pin 50 is positioned at the same angle as the guide groove 44. The spring force of the spring 43 then causes the connecting pin 41 to protrude forward (FIG. 5). At this time, the lock pin 50 slides along the guide groove 44. The lock pin 50 then abuts against the closed tip 44e of the guide groove 44, restricting the protrusion of the connecting pin 41. Therefore, the connecting pin 41 is prevented from coming off the head portion 10. At this time, the tip 41e of the connecting pin 41 is retracted into the pin hole 17, which is located forward (lower in FIG. 5) of the connecting recess 15. This releases the locked state, allowing the yoke die 30 (FIG. 4) to be separated from the head portion 10.

[0052] When using the crimping tool 1 to crimp a pipe fitting 9 (the object to be crimped), the disassembled crimping unit 3 is assembled (FIG. 3), and the pipe fitting 9 is sandwiched between the press die 20 and the yoke die 30 (FIG. 2). At this time, the connecting arm 33a of the yoke die 30 is fitted into the connecting recess 15a, and the connecting arm 33b is fitted into the connecting recess 15b. Next, the protruding connecting pin 41 (FIG. 5) is pushed in and passed through the pin hole 37 and the pin hole 17 on the back side (upper side in FIG. 4) of the connecting recess 15. At this time, the lock pin 50 slides relatively along the guide groove 44. When the lock pin 50 reaches the proximal end of the guide groove 44, the connecting pin 41 is turned. As a result, the lock pin 50 is positioned in the lock groove 45, as shown in FIG. 4, and the connecting member 40 is locked. Furthermore, as shown in FIG. 10, the crimping portion 3 is positioned in the pipe axial direction of the pipe joint 9 (left and right in FIG. 10) by the convex ring 9r of the pipe joint 9 and the end ring 9e fitted into the end flange 9f.

[0053] During the assembly, if the press die 20 is mistakenly attached to the head part 10 with the left and right directions reversed, the held part 22 of the press die 20 will not fit with the holding part 11 of the head part 10, and they will not be able to be fitted together. First, as shown in Figure 5, the locking protrusions 24b, 24a do not fit into the locking grooves 14a, 14b. Although the narrow locking protrusion 24a can be inserted into the wide locking groove 14b, the wide locking protrusion 24b cannot be fitted into the narrow locking groove 14a. As shown in Figure 6, even if the locking protrusion 24b is forcibly pressed into the locking groove 14a, the connecting hole 25 is shifted in the width direction from the piston 4p by the width difference (Lb - La) between the inner surface portions 12b and 12a, and the piston 4p cannot be inserted into the connecting hole 25. Even if the piston 4p is forcibly inserted, the inclined outer surface portions 26b, 26a and the inclined inner surface portions 16a, 16b do not match, so the piston 4p cannot be fitted completely into the connecting hole 25. Therefore, the press die 20 cannot be connected to the piston 4p. This makes it possible to reliably prevent the press die 20 from being erroneously attached to the head portion 10. The worker can easily recognize that the orientation of the press die 20 is incorrect because the held portion 22 does not match the holding portion 11. Then, by correcting the orientation of the press die 20, it can be correctly attached to the head portion 10.

[0054] As shown in Figure 7, if the yoke die 30 is mistakenly attached to the head portion 10 with the left and right sides reversed during assembly, the connected portion 33 of the yoke die 30 will not align with the connecting portion 13 of the head portion 10, and they will not be able to be connected. That is, as shown in FIGS. 7 to 9, although the thin-walled connecting arm 33a can be inserted into the connecting recess 15b on the large opening side, the thick-walled connecting arm 33b cannot be fitted into the connecting recess 15a on the small opening side. Furthermore, as shown in Figure 8, when attempting to connect the connecting portion 13b on the large opening side to the connecting arm 33a inserted therein with a large diameter connecting pin 41b, the large diameter connecting pin 41b can be inserted into the large diameter pin hole 17b of the connecting portion 13b, but the large diameter connecting pin 41b cannot be inserted into the small diameter pin hole 37a of the connecting arm 33a.

[0055] The connecting pins 41 are prevented from coming off and cannot be separated from the head portion 10. However, if they were to be separated, as shown in FIG. 9, it is possible that an operator might try to fit the larger-diameter connecting pin 41b into the smaller-diameter connecting portion 13a, or the smaller-diameter connecting pin 41a into the larger-diameter connecting portion 13b. Because the larger-diameter connecting pin 41b cannot be inserted into the smaller-diameter pin hole 17a, the operator can recognize that the connecting pins have been mixed up. On the other hand, the smaller-diameter connecting pin 41a can be inserted into the larger-diameter pin holes 17b and 37a. However, the lock pin 50 cannot be securely fitted into the guide groove 44 and lock groove 45 of the connecting pin 41a, and the connecting pin 41a cannot be fixed (locked) to the head portion 10.

[0056] This reliably prevents the yoke die 30 from being incorrectly attached to the head portion 10. The worker can easily recognize that the orientation of the yoke die 30 is incorrect because the connected portion 33 and the connecting portion 13 do not match and the connecting pin 41 cannot be inserted or locked. Then, by correcting the orientation of the yoke die 30, it can be correctly attached to the head portion 10.

[0057] After the crimping portion 3 is properly assembled in this manner, the piston 4p is driven forward as shown by the white arrow in FIG. 10 to move the press die 20 upward in FIG. 10 , thereby crimping the pipe fitting 9 to be crimped between the press die 20 and the yoke die 30. Because the crimping portion 3 is properly assembled, the pipe fitting 9 can be properly crimped. In particular, the end of the semi-circular compression mark 92 formed by the compression protrusion 21 of the press die 20 and the end of the semi-circular compression mark 93 formed by the compression protrusion 31 of the yoke die 30 overlap circumferentially with a slight offset in the axial direction of the pipe fitting 9, thereby forming a continuous annular compression mark 90 around the entire circumference of the pipe fitting 9. This prevents gas or liquid leakage from the pipe fitting 9 after the crimping operation.

[0058] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims. For example, from the viewpoint of preventing erroneous installation of the press die 20, it is sufficient that the holding portion and the held portion are asymmetrical with respect to the axis, and the connecting portion and the connected portion do not necessarily have to be asymmetrical. From the viewpoint of preventing erroneous installation of the yoke die 30, it is sufficient that the connecting portion and the connected portion are asymmetrical with respect to the axis, and the holding portion and the held portion do not necessarily have to be asymmetrical.

[0059] It is sufficient that at least a portion of the holding portion is asymmetric and that a portion of the held portion corresponding to the asymmetry is asymmetric; other portions of the holding portion and the held portion may be symmetric. For example, the locking groove and locking protrusion may be asymmetric and the holding portion and the held portion may be symmetric. The angles θa, θb of the inclined inner surface portion and the inclined outer surface portion may be asymmetric and the holding portion and the held portion may be symmetric. The widths La, Lb of the inner surface portion 12 and the outer surface portion 23 may be different and the holding portion and the held portion may be symmetric. The locking groove and locking protrusion may be asymmetric, the angles θa, θb of the inclined inner surface portion and the inclined outer surface portion may be different, and the widths La, Lb of the inner surface portion 12 and the outer surface portion 23 may be the same.

[0060] The press die 20 may have a locking groove formed therein, and the head portion 10 may have a locking protrusion that slidably fits into the locking groove. The connected portion of the yoke die 30 may have a connecting recess, and the connecting portion of the head portion 10 may have a connecting arm.

[0061] It is sufficient that at least a portion of the connecting portion is asymmetric and the portion of the connected portion corresponding to the asymmetry is asymmetric, and other portions of the connecting portion and the connected portion may be symmetric. For example, the connecting recess and connecting arm may be asymmetric and the pin holes 17, 37 may be symmetric. Alternatively, the pin holes 17, 37 may be asymmetric and the connecting recess and connecting arm may be symmetric. [Industrial Applicability]

[0062] The present invention is applicable to a crimping tool for crimping and joining pipe joints fitted to the pipe ends of air conditioning pipes and cold / hot water supply pipes, for example. [Explanation of symbols]

[0063] L axis 1 Crimping tool 2 Tool body 3 Crimping area 4. Advance / retreat drive unit 4p piston (output shaft) 9 Pipe fittings (objects) 10 Head 11 Retaining recess (retaining portion) 12,12a,12a inner part 13,13a,13b connection part 14,14a,14a Locking groove 15, 15a, 15b Connection recess 16,16a,16b Slanted inner surface 17,17a,17b pin hole 18,18a,18b Lateral inner surface 20 Press Dies 22 Outer surface (held part) 23,23a,23b External part 24,24a,24b Locking protrusion 25 Connection hole (connection part) 26,26a, 26b Slanted outer surface 27,27a,27b Lateral outer surface part 30 York Dice 33,33a,33b Connecting arm (connected part) 37,37a,37b pin hole 40 Connecting member 41, 41a, 41b Connecting pin 44 Guide groove 45 Lock groove 50 Lock pin 51 Locking spring

Claims

1. A crimping tool for crimping an object, a tool body in which the forward / backward drive unit is housed; a head portion provided at a tip end of the tool body in the axial direction, the head portion having a holding portion extending across an axis of the tool body and extending to both sides in a width direction perpendicular to the axis, and a pair of connecting portions sandwiching the holding portion on both sides in the width direction; a press die having a held portion that is detachably attached to the holding portion and is held so as to be movable forward and backward in the axial direction; a yoke die having a pair of connected portions that are detachably connected to the pair of connecting portions, respectively, and facing the press die on the tip side of the press die in the axial direction with the object sandwiched therebetween; an output shaft of the forward / backward driving unit is provided on the axis line, and the output shaft penetrates the head unit and is detachably connected to the press die, At least one of the holding portion and the pair of connecting portions is asymmetric with respect to the axis, The held portion and the pair of connected portions are asymmetric with respect to the axis, A crimping tool characterized in that the head portion, the press die, and the yoke die are assembled from a disassembled state while the object is sandwiched between the press die and the yoke die.

2. the holding portion includes a holding recess formed in the head portion so as to be open toward the tip end side and configured to accommodate the press die so as to be movable forward and backward; the held portion includes an outer surface facing an inner surface of the holding recess of the press die, Inner surface portions on both sides of the inner surface in the width direction across the axis are asymmetric with respect to the axis, 2. The crimping tool according to claim 1, wherein outer surface portions on both sides of the axis in the width direction of the outer surface are asymmetric with respect to the axis.

3. a locking groove extending in the axial direction is formed in one of the inner surface portion and the outer surface portion on the same side in the width direction, a locking protrusion that is fitted into the locking groove so as to be slidable in the axial direction is formed on the other of the inner surface portion and the outer surface portion on the same side; 3. The crimping tool according to claim 2, wherein the locking grooves and the locking protrusions on both sides in the width direction are asymmetrical in cross section perpendicular to the axis.

4. The inner surface portions on both sides each have an inclined inner surface portion that inclines toward the tip side as it moves away from the axis in the width direction, The outer surface portions on both sides each have an inclined outer surface portion that inclines toward the tip side as it moves away from the axis in the width direction, 4. The crimping tool according to claim 2, wherein the inclination angles of the inclined inner surface portions on both sides and the inclined outer surface portions on both sides are different from each other.

5. 5. The crimping tool according to claim 2, wherein the widths of the inner surface portions on both sides are different from each other, and the widths of the outer surface portions on both sides are different from each other.

6. One of the pair of connecting portions and the pair of connected portions on both sides in the width direction has a connecting recess, and the other has a connecting arm that is fitted into the connecting recess, The crimping tool according to any one of claims 1 to 5, characterized in that the connecting recesses on both sides of the width direction and the connecting arms have different sizes in the axial direction and in the thickness direction perpendicular to the width direction.

7. The connecting portion and the connected portion on the same side in the width direction are connected to each other by a connecting pin passed through a pin hole formed in the connecting portion and the connected portion, The crimping tool according to any one of claims 1 to 6, characterized in that the pin holes on both sides in the width direction have different hole diameters, and the connecting pins on both sides in the width direction have different diameters.

8. One of the pair of connecting portions and the pair of connected portions on both sides in the width direction has a connecting recess, and the other has a connecting arm that is fitted into the connecting recess, The connecting recesses on both sides in the width direction and the connecting arms on both sides in the axial direction and the thickness direction perpendicular to the width direction are different in size from each other, The connecting portion and the connected portion on the same side in the width direction are connected to each other by a connecting pin passed through a pin hole formed in the connecting portion and the connected portion, The pin holes on both sides in the width direction have different hole diameters, and the connecting pins on both sides in the width direction have different diameters, The larger connecting pin and pin hole are disposed in the connecting recess and the connecting arm in the larger connecting portion and connected portion, The crimping tool according to any one of claims 1 to 7, characterized in that the smaller connecting pin and pin hole are arranged in the connecting portion and connected portion on the smaller side of the connecting recess and connecting arm.

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